FN Thomson Reuters Web of Science™ VR 1.0 PT B AU Burkert, VD AF Burkert, V. D. BE Hammer, HW Kleber, V Thoma, U Schmiedan, H TI The JLab upgrade -Studies of the nucleon with CLAS12 Selected topics SO PROCEEDINGS OF THE 11TH WORKSHOP ON THE PHYSICS OF EXCITED NUCLEONS LA English DT Proceedings Paper CT 11th Workshop on the Physics of Excited Nucleons CY SEP 05-08, 2007 CL Univ Bonn, Bonn, GERMANY SP Deutsch Forschungsgemeinsch, Forschungszentrum Julich, Univ Bonn, CAEN SpA, sysGen GmbH, W IE NE R Plein & Baus GmbH HO Univ Bonn ID VIRTUAL COMPTON-SCATTERING; SPIN STRUCTURE FUNCTIONS; PROTON; Q(2)-DEPENDENCE; NEUTRON; RESONANCE AB An overview is presented on the program to study the nucleon structure at the 12 GeV JLab upgrade using the CLAS12 detector. The focus is on deeply virtual exclusive processes to access the generalized parton distributions, semi-inclusive processes to study transverse momentum dependent distribution functions and inclusive spin structure functions, and resonance transition form factors at high Q(2) and with high precision. C1 Jefferson Lab, Newport News, VA USA. RP Burkert, VD (reprint author), Jefferson Lab, Newport News, VA USA. NR 47 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-85143-1 PY 2008 BP 137 EP 143 PG 7 WC Physics, Applied; Physics, Nuclear SC Physics GA BII37 UT WOS:000259692400025 ER PT B AU Lee, TSH AF Lee, T. -S. H. BE Hammer, HW Kleber, V Thoma, U Schmiedan, H TI Dynamical coupled-channels analysis at EBAC SO PROCEEDINGS OF THE 11TH WORKSHOP ON THE PHYSICS OF EXCITED NUCLEONS LA English DT Proceedings Paper CT 11th Workshop on the Physics of Excited Nucleons CY SEP 05-08, 2007 CL Univ Bonn, Bonn, GERMANY SP Deutsch Forschungsgemeinsch, Forschungszentrum Julich, Univ Bonn, CAEN SpA, sysGen GmbH, W IE NE R Plein & Baus GmbH HO Univ Bonn ID MODEL AB The status of the dynamical coupled-channels analysis at EBAC is reported. C1 [Lee, T. -S. H.] Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Lee, TSH (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-85143-1 PY 2008 BP 157 EP 161 PG 5 WC Physics, Applied; Physics, Nuclear SC Physics GA BII37 UT WOS:000259692400028 ER PT B AU Aznauryan, I Burkert, V AF Aznauryan, I. Burkert, V. BE Hammer, HW Kleber, V Thoma, U Schmiedan, H TI Electroexcitation of the Roper resonance from CLAS data SO PROCEEDINGS OF THE 11TH WORKSHOP ON THE PHYSICS OF EXCITED NUCLEONS LA English DT Proceedings Paper CT 11th Workshop on the Physics of Excited Nucleons CY SEP 05-08, 2007 CL Univ Bonn, Bonn, GERMANY SP Deutsch Forschungsgemeinsch, Forschungszentrum Julich, Univ Bonn, CAEN SpA, sysGen GmbH, W IE NE R Plein & Baus GmbH HO Univ Bonn ID CONSTITUENT QUARK-MODEL; ELECTROPRODUCTION; BARYONS AB The helicity amplitudes of the electroexcitation of the Roper resonance on proton are extracted at 1.7 < Q(2) < 4.2 GCV(2) from recent high precision JLab-CLAS cross sections data and longitudinally polarized beam asymmetry for pi(+) electroproduction on protons. The analysis is made using two approaches, dispersion relations and unitary isobar model, which give consistent results. It is found that the transverse helicity amplitude for the gamma*p - P-11(1440) transition, which is large and negative at Q(2) = 0, becomes large and positive at Q(2) similar or equal to 2 GeV2, and then drops slowly with Q(2). Longitudinal helicity amplitudes that was previously found from CLAS data as large and positive at Q(2) = 0.4, 0.65 GeV2, drops with Q(2). These results rule out the presentation of P-11(1440) as a q(3)G hybrid state, and provide strong evidence in favor of this resonance as a first radial excitation of the 3q ground state. C1 [Aznauryan, I.; Burkert, V.] Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Aznauryan, I (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-85143-1 PY 2008 BP 231 EP 233 PG 3 WC Physics, Applied; Physics, Nuclear SC Physics GA BII37 UT WOS:000259692400051 ER PT B AU Ziegler, V AF Ziegler, V. BE Hammer, HW Kleber, V Thoma, U Schmiedan, H TI Cascade resonance properties from charm baryon decays at BABAR SO PROCEEDINGS OF THE 11TH WORKSHOP ON THE PHYSICS OF EXCITED NUCLEONS LA English DT Proceedings Paper CT 11th Workshop on the Physics of Excited Nucleons CY SEP 05-08, 2007 CL Univ Bonn, Bonn, GERMANY SP Deutsch Forschungsgemeinsch, Forschungszentrum Julich, Univ Bonn, CAEN SpA, sysGen GmbH, W IE NE R Plein & Baus GmbH HO Univ Bonn ID PARITY; SPIN AB We present studies of hyperon and hyperon resonance production in charm baryon decays at BABAR. Two-body decay spin formalisms are extended to three-body final states and are used to study Xi(1530)degrees production in Lambda(+)(c) decay. Similarly, the properties of the Xi(1690)degrees are extracted from a detailed isobar model analysis of the Lambda(+)(c) -> Lambda KsK+ Dalitz plot. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Ziegler, V (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-85143-1 PY 2008 BP 234 EP 236 PG 3 WC Physics, Applied; Physics, Nuclear SC Physics GA BII37 UT WOS:000259692400052 ER PT B AU Capstick, S Svarc, A Tiator, L Gegelia, J Giannini, MM Santopinto, E Hanhart, C Scherer, S Lee, TSH Sato, T Suzuki, N AF Capstick, S. Svarc, A. Tiator, L. Gegelia, J. Giannini, M. M. Santopinto, E. Hanhart, C. Scherer, S. Lee, T. -S. H. Sato, T. Suzuki, N. BE Hammer, HW Kleber, V Thoma, U Schmiedan, H TI The physical meaning of scattering matrix singularities in coupled-channel formalisms BRAG 2007 Workshop summary SO PROCEEDINGS OF THE 11TH WORKSHOP ON THE PHYSICS OF EXCITED NUCLEONS LA English DT Proceedings Paper CT 11th Workshop on the Physics of Excited Nucleons CY SEP 05-08, 2007 CL Univ Bonn, Bonn, GERMANY SP Deutsch Forschungsgemeinsch, Forschungszentrum Julich, Univ Bonn, CAEN SpA, sysGen GmbH, W IE NE R Plein & Baus GmbH HO Univ Bonn ID CHIRAL PERTURBATION-THEORY; QUANTUM FIELD THEORIES; ZWEIG-IIZUKA RULE; P-WAVE BARYONS; RELATIVISTIC QUARK-MODEL; 3-BODY FORCE MODEL; HADRONIC LOOPS; PHENOMENOLOGICAL LAGRANGIANS; PAIR-CREATION; ELECTROMAGNETIC-EXCITATION AB The physical meaning of bare and dressed scattering matrix singularities has been investigated. Special attention has been attributed to the role of the well-known invariance of the scattering matrix with respect to the field transformation of the effective Lagrangian. Examples of evaluating bare and dressed quantities in various models are given. C1 [Capstick, S.] Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. [Svarc, A.] Rudjer Boskovic Inst, Zagreb, Croatia. [Tiator, L.; Gegelia, J.; Scherer, S.] Johannes Gutenberg Univ Mainz, Inst Kernphysik, Mainz, Germany. [Giannini, M. M.; Santopinto, E.] Univ Genoa, Dipartimento Fis, Genoa, Italy. [Hanhart, C.] Inst Kernphysik, Forschungszentrum Julich, Julich, Germany. [Lee, T. -S. H.] Argonne Natl Lab, Phys Div, Argonne, IL USA. [Lee, T. -S. H.; Sato, T.; Suzuki, N.] Thomas Jefferson Natl Accelerator Fac, Excited Baryon Analysis Ctr, Newport News, VA USA. [Sato, T.; Suzuki, N.] Osaka Univ, Dept Phys, Toyonaka, Osaka, Japan. [Giannini, M. M.; Santopinto, E.] INFN, Genoa, Italy. RP Capstick, S (reprint author), Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. EM capstick@phy.fsu.edu; svarc@irb.hr; tiator@kph.uni-mainz.de; santopinto@ge.infn.it; c.hanhart@fz-juelich.de; Lee@theory.phy.anl.gov NR 103 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-85143-1 PY 2008 BP 266 EP + PG 3 WC Physics, Applied; Physics, Nuclear SC Physics GA BII37 UT WOS:000259692400060 ER PT B AU Patton, RM Potok, TE AF Patton, Robert M. Potok, Thomas E. BE Banissi, E Stuart, L Jern, M Andrienko, G Marchese, FT Memon, N Alhajj, R Wyeld, TG Burkhard, RA Grinstein, G Groth, D Ursyn, A Maple, C Faiola, A Craft, B TI Identifying event impacts by monitoring the news media SO PROCEEDINGS OF THE 12TH INTERNATIONAL INFORMATION VISUALISATION SE IEEE International Conference on Information Visualisation LA English DT Proceedings Paper CT 12th International Conference Information Visualisation 2008 CY JUL 09-11, 2008 CL London, ENGLAND SP CPS, IEEE Comp Soc AB Assessing the potential property and social impacts Of an event, such as tornado or wildfire, continues to be a challenging research area. From financial markets to disaster management to epidemiology, the importance Of understanding the impacts that events create cannot be understated Our work describes an approach to fuse information from multiple sources, then to analyze the information cycles to identify prior temporal patterns related to the impact of an event. This approach is then applied to the analysis of news reports from multiple news sources pertaining to several different natural disasters. Results show that our approach can project the severity of the impacts of certain natural disasters, such as heat waves on droughts and wild fires. In addition, results show that specific types of disaster consistently produce similar impacts when each time they occur. C1 [Patton, Robert M.; Potok, Thomas E.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Patton, RM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Patton, Robert/0000-0002-8101-0571; Potok, Thomas/0000-0001-6687-3435 NR 19 TC 1 Z9 1 U1 0 U2 5 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3268-4 J9 IEEE INT CON INF VIS PY 2008 BP 333 EP 337 PG 5 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Imaging Science & Photographic Technology SC Computer Science; Engineering; Imaging Science & Photographic Technology GA BIF81 UT WOS:000259178400051 ER PT B AU Agouzal, A Lipnikov, K Vassilevski, Y AF Agouzal, Abdellatif Lipnikov, Konstantin Vassilevski, Yuri BE Brewer, ML Marcum, D TI Generation of quasi-optimal meshes based on a posteriori error estimates SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA ID ADAPTATION; RECOVERY AB We study methods for recovering tensor metrics from given error estimates and properties of meshes which are quasi-uniform in these metrics. We derive optimal upper and lower bounds for the global error on these meshes. We demonstrate with numerical experiments that the edge-based error estimates are preferable for recovering anisotropic metrics than the conventional element-based errors estimates. C1 [Agouzal, Abdellatif] Univ Lyon 1, Anal Numer Lab, F-69622 Villeurbanne, France. [Lipnikov, Konstantin] Los Alamos Natl Lab, Los Alamos, NM USA. [Vassilevski, Yuri] Inst Numer Math, Moscow 119333, Russia. RP Agouzal, A (reprint author), Univ Lyon 1, Anal Numer Lab, F-69622 Villeurbanne, France. EM Abdellatif.Agouzal@univ-lyon1.fr; lipnikov@lanl.gov; vasilevs@dodo.inm.ras.ru RI Vassilevski, Yuri/A-6068-2016 FU RFBR [04-07-90336] FX Research of the third author has been supported partially by the RFBR project 04-07-90336 and the academic program Optimal methods for problems of mathematical physics. NR 16 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 139 EP + DI 10.1007/978-3-540-75103-8_8 PG 3 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200008 ER PT B AU Clark, BW AF Clark, Brett W. BE Brewer, ML Marcum, D TI Removing small features with real CAD operations SO Proceedings of the 16th International Meshing Roundtable LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA AB Preparing Computer Aided Design models for successful mesh generation continues to be a crucial part of the design to analysis process. A common problem in CAD models is features that are very small compared to the desired mesh size. Small features exist for a variety of reasons and can require an excessive amount of elements or inhibit mesh generation all together. Many of the tools for removing small features modify only the topology of the model (often in a secondary topological representation of the model) leaving the underlying geometry as is. The availability of tools that actually modify the topology and underlying geometry in the boundary representation (B-rep) model is much more limited regardless of the inherent advantages of this approach. This paper presents a process for removing small featrues from a B-rep model using almost solely functionality provided by the underlying solid modeling kernel. The process cuts out the old topology and reconstructs new topology and geometry to close the volume. The process is quite general and can be applied to complex configurations of unwanted topology. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Clark, BW (reprint author), Sandia Natl Labs, POB 5800,MS 0376, Albuquerque, NM 87185 USA. NR 14 TC 1 Z9 4 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 183 EP 198 DI 10.1007/978-3-540-75103-8_11 PG 16 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200011 ER PT B AU Merkley, K Ernst, C Shepherd, JF Borden, MJ AF Merkley, Karl Ernst, Corey Shepherd, Jason F. Borden, Michael J. BE Brewer, ML Marcum, D TI Methods and applications of generalized sheet insertion for hexahedral meshing SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA DE hexahedra; meshing; dual; boundary layers; refinement ID GENERATION; ALGORITHM AB This paper presents methods and applications of sheet insertion in a hexahedral mesh. A hexahedral sheet is dual to a layer of hexahedra in a hexahedral mesh. Because of symmetries within a hexahedral element, every hexahedral mesh can be viewed as a collection of these sheets. It is possible to insert new sheets into an existing mesh, and these new sheets can be used to define new mesh boundaries, refine the mesh, or in some cases can be used to improve quality in an existing mesh. Sheet insertion has a broad range of possible applications including mesh generation, boundary refinement, R-adaptivity and joining existing meshes. Examples of each of these applications are demonstrated. C1 [Merkley, Karl] Computat Simulat Software LLC, Amer Fork, UT 84003 USA. [Ernst, Corey] Elemental Technol Inc, Amer Fork, UT USA. [Shepherd, Jason F.; Borden, Michael J.] Sandia Natl Labs, Albuquerque, NM USA. RP Merkley, K (reprint author), Computat Simulat Software LLC, Amer Fork, UT 84003 USA. EM karl@csimsoft.com; corey@elemtech.com; jfsheph@sandia.gov; mborden@sandia.gov RI Borden, Michael/I-3185-2012 OI Borden, Michael/0000-0001-6633-4925 NR 26 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 233 EP + DI 10.1007/978-3-540-75103-8_14 PG 3 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200014 ER PT B AU Parrish, M Borden, M Staten, M Benzley, S AF Parrish, Michael Borden, Michael Staten, Matthew Benzley, Steven BE Brewer, ML Marcum, D TI A selective approach to conformal refinement of unstructured hexahedral finite element meshes SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA AB Hexahedral refinement increases the density of an all-hexahedral mesh in a specified region, improving numerical accuracy. Previous research using solely sheet refinement theory made the implementation computationally expensive and unable to effectively handle concave refinement regions and self-intersecting hex sheets. The Selective Approach method is a new procedure that combines two diverse methodologies to create an efficient and robust algorithm able to handle the above stated problems. These two refinement methods are: 1) element by element refinement and 2) directional refinement. In element by element refinement, the three inherent directions of a Hex are refined in one step using one of seven templates. Because of its computational superiority over directional refinement, but its inability to handle concavities, element by element refinement is used in all areas of the specified region except regions local to concavities. The directional refinement scheme refines the three inherent directions of a hexahedron separately on a hex by hex basis. This differs from sheet refinement which refines hexahedra using hex sheets. Directional refinement is able to correctly handle concave refinement regions. A ranking system and propagation scheme allow directional refinement to work within the, confines of the Selective Approach Algorithm. C1 [Parrish, Michael; Benzley, Steven] Brigham Young Univ, Provo, UT 84602 USA. [Borden, Michael; Staten, Matthew] Sandia Natl Labs, Albuquerque, NM USA. RP Parrish, M (reprint author), Brigham Young Univ, Provo, UT 84602 USA. EM mhp@et.byu.edu; mborden@sandia.gov; mlstate@sandia.gov; seb@byu.edu RI Borden, Michael/I-3185-2012 OI Borden, Michael/0000-0001-6633-4925 NR 13 TC 3 Z9 3 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 251 EP + DI 10.1007/978-3-540-75103-8_15 PG 3 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200015 ER PT B AU Pebay, PP Stephenson, MB Fortier, LA Owen, SJ Melander, DJ AF Pebay, Philippe P. Stephenson, Michael B. Fortier, Leslie A. Owen, Steven J. Melander, Darryl J. BE Brewer, ML Marcum, D TI pCAMAL: An embarrassingly parallel hexahedral mesh generator SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA AB This paper describes a distributed-memory, embarrassingly parallel hexahedral mesh generator, pCAMAL (parallel CUBIT Adaptive Mesh Algorithm Library). pCAMAL utilizes the sweeping method following a serial step of geometry decomposition conducted in the CUBIT geometry preparation and mesh generation tool. The utility of pCAMAL in generating large meshes is illustrated, and linear speed-up under load-balanced conditions is demonstrated. C1 [Pebay, Philippe P.; Fortier, Leslie A.; Owen, Steven J.; Melander, Darryl J.] Sandia Natl Labs, POB 969,MS 9051, Livermore, CA 94551 USA. [Stephenson, Michael B.] M B Stephenson & Assoc, Provo, UT 84604 USA. RP Pebay, PP (reprint author), Sandia Natl Labs, POB 969,MS 9051, Livermore, CA 94551 USA. EM pppebay@sandia.gov; mbsteph@sandia.gov; laforti@sandia.gov; sjowen@sandia.gov; djmelan@sandia.gov OI Pebay, Philippe/0000-0002-2311-3775 FU United States Department of Energy [DE-AC04-94-AL85000]; Office of Defense Programs. FX This work was supported by the United States Department of Energy, Office of Defense Programs. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the United States Department of Energy under contract DE-AC04-94-AL85000. NR 14 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 269 EP + DI 10.1007/978-3-540-75103-8_16 PG 3 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200016 ER PT B AU Ahn, HT Shashkov, M AF Ahn, Hyung Taek Shashkov, Mikhail BE Brewer, ML Marcum, D TI Geometric algorithms for 3D interface reconstruction SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA DE interface reconstruction; polyhedral mesh; volume of fluid; moment of fluid ID INCOMPRESSIBLE 2-PHASE FLOWS; FRONT-TRACKING METHOD; VOLUME TRACKING AB We describe geometrical algorithms for interface reconstructions for 3D generalized polyhedral meshes. Three representative piece-wise linear interface calculation methods are considered, namely gradient based method, least squares volume-of-fluid interface reconstruction algorithm, and moment-of-fluid method. Geometric algorithms for the 3D interface reconstructions are described. Algorithm for the intersection of a convex polyhedron with half-space is presented with degenerate cases. Fast iterative methods for volume matching interface computation are introduced. The numerical optimization method for interface normal computation is presented, and its super-linearly convergence is demonstrated. Finally, actual reconstruction of complex geometry is demonstrated. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Shashkov, Mikhail] Los Alamos Natl Lab, Los Alamos, NM USA. RP Ahn, HT (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM htahn@lanl.gov; shashkov@lanl.gov FU Los Alamos National Laboratory FX This work was supported by the Advanced Simulation and Computing (ASC) program at the Los Alamos National Laboratory. NR 23 TC 4 Z9 4 U1 3 U2 6 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 405 EP + DI 10.1007/978-3-540-75103-8_23 PG 3 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200023 ER PT B AU Pebay, PP Thompson, D AF Pebay, Philippe P. Thompson, David BE Brewer, ML Marcum, D TI K-Compatible tessellations SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA AB The vast majority of visualization algorithms for finite element (FE) simulations assume that linear constitutive relationships are used to interpolate values over an element, because the polynomial order of the FE basis functions used in practice has traditionally been low - linear or quadratic. However, higher order FE solvers, which become increasingly popular, pose a significant challenge to visualization systems as the assumptions of the visualization algorithms are violated by higher order solutions. This paper presents a method for adapting linear visualization algorithms to higher order data through a careful examination of a linear algorithm's properties and the assumptions it makes. This method subdivides higher order finite elements into regions where these assumptions hold (kappa-compatibility). Because it is arguably one of the most useful visualization tools, isosurfacing is used as an example to illustrate our methodology. C1 [Thompson, David] Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. RP Pebay, PP (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. EM pppebay@sandia.gov; dcthomp@sandia.gov OI Pebay, Philippe/0000-0002-2311-3775 FU United States Department of Energy [DE-AC04-94-AL85000.] FX This work was supported by the United States Department of Energy, Office of Defense Programs. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the United States Department of Energy under contract DE-AC04-94-AL85000. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 423 EP + DI 10.1007/978-3-540-75103-8_24 PG 2 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200024 ER PT B AU Pebay, PP Thompson, D Shepherd, J Knupp, P Lisle, C Magnotta, VA Grosland, NM AF Pebay, Philippe P. Thompson, David Shepherd, Jason Knupp, Patrick Lisle, Curtis Magnotta, Vincent A. Grosland, Nicole M. BE Brewer, ML Marcum, D TI New applications of the Verdict library for standardized mesh verification pre, post, and end-to-end processing SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA ID QUALITY MEASURES; OPTIMIZATION; GENERATION AB Verdict is a collection of subroutines for evaluating the geometric qualities of triangles, quadrilaterals, tetrahedra, and hexahedra using a variety of functions. A quality is a real number assigned to one of these shapes depending on its particular vertex coordinates. These functions are used to evaluate the input to finite element, finite volume, boundary element, and other types of solvers that approximate the solution to partial differential equations defined over regions of space. This article describes the most recent version of Verdict and provides a summary of the main properties of the quality functions offered by the library. It finally demonstrates the versatility and applicability of Verdict by illustrating its use in several scientific applications that pertain to pre, post, and end-to-end processing. C1 [Pebay, Philippe P.; Thompson, David] Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. [Shepherd, Jason; Knupp, Patrick] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Lisle, Curtis] Knowledgevis Llc, Maitland, FL 32751 USA. [Magnotta, Vincent A.; Grosland, Nicole M.] Univ Iowa, Iowa City, IA 52242 USA. RP Pebay, PP (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. EM pppebay@sandia.gov; dcthomp@sandia.gov; jfsheph@sandia.gov; pknupp@sandia.gov; clisle@ieee.org; vincent-magnotta@uiowa.edu; nicole-grosland@uiowa.edu OI Pebay, Philippe/0000-0002-2311-3775 FU United States Department of Energy [DE-AC04-94-AL85000]; NIH [EB005973, EB001501, U54 EB005149] FX These authors were supported by the United States Department of Energy, Office of Defense Programs. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the United States Department of Energy under contract DE-AC04-94-AL85000. These authors gratefully acknowledge the financial support provided by NIH Awards EB005973, EB001501, and U54 EB005149. NR 43 TC 1 Z9 2 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 535 EP + DI 10.1007/978-3-540-75103-8_30 PG 5 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200030 ER PT B AU Owen, SJ Clark, BW Melander, DJ Brewer, M Shepherd, JF Merkley, K Ernst, C Morris, R AF Owen, Steven J. Clark, Brett W. Melander, Darryl J. Brewer, Michael Shepherd, Jason F. Merkley, Karl Ernst, Corey Morris, Randy BE Brewer, ML Marcum, D TI An immersive topology environment for meshing SO PROCEEDINGS OF THE 16TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 16th International Meshing Roundtable CY OCT 14-17, 2007 CL Seattle, WA DE geometry simplification; sweep decomposition; design through analysis; hexahedra; sweeping; assembly meshing; imprint/merge; meshing user interface AB The Immersive Topology Environment for Meshing (ITEM) is a wizard-like environment, built on top of the CUBIT Geometry and Meshing Toolkit. ITEM is focused on three main objectives: 1) guiding the user through the simulation model preparation workflow; 2) providing the user with intelligent options based upon the current state of the model;, and 3) where appropriate, automating as much of the process as possible. To accomplish this, a diagnostic-solution approach is taken. Based upon diagnostics of the current state of the model, specific solutions for a, variety of common tasks are provided to the user. Some of these tasks include geometry simplification, small feature suppression, resolution of misaligned assembly parts, decomposition for hex meshing, and source and target selection for sweeping. The user may scroll through a list of intelligent solutions for a specific diagnostic and entity, view a graphical preview of each solution and quickly perform the solution to resolve the problem. In many cases, automatic solutions for these tasks can be generated and executed if the user chooses. This paper will discuss the various diagnostics and geometric reasoning algorithms and approaches taken by ITEM to determine solutions for preparing an analysis model. C1 [Owen, Steven J.; Clark, Brett W.; Melander, Darryl J.; Brewer, Michael; Shepherd, Jason F.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Merkley, Karl; Ernst, Corey; Morris, Randy] El Techn, Amer Fork, UT USA. RP Owen, SJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM sjowen@sandia.gov; bwclark@sandia.gov; djmelan@sandia.gov; mbrewer@sandia.gov; jfsheph@sandia.gov; karl@elemtech.com; corey@elemtech.com; randy@elemtech.com FU United States Department of Energy [DE-AC04-94AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000. NR 22 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-75102-1 PY 2008 BP 553 EP + DI 10.1007/978-3-540-75103-8_31 PG 4 WC Engineering, Industrial; Engineering, Mechanical SC Engineering GA BGV54 UT WOS:000250802200031 ER PT B AU Shontz, SM Knupp, P AF Shontz, Suzanne M. Knupp, Patrick BE Garimella, RV TI The Effect of Vertex Reordering on 2D Local Mesh Optimization Efficiency SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA ID GRID GENERATION; IMPROVEMENT C1 [Shontz, Suzanne M.] Penn State Univ, Dept Comp Sci & Engn, 343J Informat Sci & Technol Bldg, University Pk, PA 16802 USA. [Knupp, Patrick] Appl Math & Applicat, Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shontz, SM (reprint author), Penn State Univ, Dept Comp Sci & Engn, 343J Informat Sci & Technol Bldg, University Pk, PA 16802 USA. EM shontz@cse.psu.edu; pknupp@sandia.gov OI Shontz, Suzanne/0000-0002-4874-0812 FU NSF [CNS 0720749]; The Pennsylvania State University; Department of Energy's Mathematics, Information, and Computational Science Program (SC-31); U.S. Department of Energy [DEACO4-94AL85000] FX This work was funded in part by NSF grant CNS 0720749 and a Grace Woodward grant from The Pennsylvania State University.; This work was funded by the Department of Energys Mathematics, Information, and Computational Science Program (SC-31) and was performed at Sandia National Laboratories. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the U.S. Department of Energy under contract DEACO4-94AL85000. This work was performed by an employee of the U.S. Government or under U.S. Government contract. The U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution,or allow others to do so, for U.S. Government purposes. NR 22 TC 6 Z9 6 U1 1 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 107 EP + DI 10.1007/978-3-540-87921-3_7 PG 3 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600007 ER PT B AU Clark, BW Hanks, BW Ernst, CD AF Clark, Brett W. Hanks, Byron W. Ernst, Corey D. BE Garimella, RV TI Conformal Assembly Meshing with Tolerant Imprinting SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA AB Solid assembly meshing has all of the same "dirty geometry" induced issues as single part meshing but also has the difficulty associated with generating a conformal mesh between solids where solid-solid interfaces are not obvious. Mesh generators usually don't have CAD assembly constraint information to identify interfacing solids and must therefore rely on geometric proximity to deduce these interactions. "Slop" in the positioning and alignment of parts in the assembly makes automatically discovering the interfaces and generating a conformal mesh at the interfaces very difficult. Most of the efforts in this area resort, to some sort of discrete representation to deal with these issues losing the capability to do further solid modeling engine operations often necessary for all-hexahedral meshing. This paper presents a method for defining the non-manifold interfaces between volumes in an assembly required for generating a conformal mesh while maintaining the original solid modeling engine format. C1 [Clark, Brett W.; Hanks, Byron W.] Sandia Natl Labs, POB 5800,MS 0376, Albuquerque, NM 87185 USA. [Ernst, Corey D.] Elemental Technol Inc, Portland, OR 84003 USA. RP Clark, BW (reprint author), Sandia Natl Labs, POB 5800,MS 0376, Albuquerque, NM 87185 USA. EM bwclark@sandia.gov; bwhanks@sandia.gov; corey@elemtech.com FU Sandia Corporation, a Lockheed Martin Company; United States Department of Energys National Nuclear Security Administration [DE-AC04-94AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energys National Nuclear Security Administration under contract DE-AC04-94AL85000. NR 2 TC 7 Z9 7 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 267 EP + DI 10.1007/978-3-540-87921-3_16 PG 2 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600016 ER PT B AU Hecht, F Kuate, R Tautges, T AF Hecht, Frederic Kuate, Raphael Tautges, Timothy BE Garimella, RV TI A New Set of Hexahedral Meshes Local Transformations SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA ID CUBICAL POLYTOPES AB The modification of hexahedral meshes is difficult to perform since their structure does not allow easy local refinement or un-refinement such that the modification does not go through the boundary. In this paper we prove that the set of hex flipping transform at ions of Bern et. al. [1] is the only possible local modification on a geometrical hex mesh with less than 5 edges per vertex. We propose a new basis of local transformations that can generate an infinite number of transformations oil hex meshes with less than 6 edges per vertex. Those results are a continuation of a previous work [9], on topological modification of hexahedral meshes. We prove that one necessary condition for filling the enclosed volume of a surface quad mesh with compatible hexes is that the number of vertices of that quad mesh with 3 edges Should be no less than 8. For quad meshes, we show the equivalence between modifying locally the number of quads on a mesh and the number of its internal vertices. C1 [Hecht, Frederic; Kuate, Raphael] Univ Paris 06, Lab Jacques Louis Lions, F-75252 Paris 05, France. [Tautges, Timothy] Computat Mech & Visualizat Dept, Sandia Natl Lab, Albuquerque, NM USA. RP Hecht, F (reprint author), Univ Paris 06, Lab Jacques Louis Lions, F-75252 Paris 05, France. EM hecht@ann.jussieu.fr; kuate@ann.jussieu.fr; tautges@mcs.anl.gov NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 451 EP + DI 10.1007/978-3-540-87921-3_27 PG 2 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600027 ER PT B AU Staten, ML Shepherd, JF Shimada, K AF Staten, Matthew L. Shepherd, Jason F. Shimada, Kenji BE Garimella, RV TI Mesh Matching - Creating Conforming Interfaces between Hexahedral Meshes SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA ID FINITE-ELEMENT; 3D AB This paper presents a new method for handling non-conforming hexahedral interfaces. One or both of the adjacent hexahedral meshes are locally modified to create a one-to-one mapping between between the mesh nodes and quadrilaterals at the interface allowing a conforming mesh to be created. In the finite element method, non-con forming interfaces are currently handled using constraint conditions such as gap-elements, tied contacts, or multi-point constraints. By creating a conforming mesh, the need for constraint conditions is eliminated resulting in a smoother, more precise numerical solution. The method presented in this paper uses hexahedral dual operations, including pillowing, sheet extraction, dicing and column collapse operations, to affect the local mesh modifications. In addition, an extension to pillowing, called sheet inflation, is introduced to handle the insertion of self-intersecting and self-touching sheets. The quality of the resultant conforming hexahedral mesh is high and the increase in number of elements is moderate. C1 [Staten, Matthew L.; Shepherd, Jason F.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Staten, Matthew L.; Shimada, Kenji] Carnegie Mellon Univ, Pittsburgh, PA USA. RP Staten, ML (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM mlstate@sandia.gov; jfsheph@sandia.gov; shimada@cmu.edu FU [DEAC04- 94AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract. DEAC04- 94AL85000 NR 22 TC 7 Z9 7 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 467 EP + DI 10.1007/978-3-540-87921-3_28 PG 3 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600028 ER PT B AU Hetmaniuk, U Knupp, P AF Hetmaniuk, U. Knupp, P. BE Garimella, RV TI A Mesh Optimization Algorithm to Decrease the Maximum Error in Finite Element Computations SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA ID LINEAR INTERPOLATION; ADAPTATION; ADAPTIVITY; TRIANGLE; CFD AB We present a mesh optimization algorithm for adaptively improving the finite element interpolation of a function of interest. The algorithm minimizes an objective function by swapping edges and moving nodes. Numerical experiments are performed on model problems. The results illustrate that the mesh optimization algorithm can reduce the W(1,infinity) semi-norm of the interpolation error. For these examples, the L(2), L(infinity), and H(1) norms decreased also. C1 [Hetmaniuk, U.; Knupp, P.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hetmaniuk, U (reprint author), Sandia Natl Labs, POB 5800,MS 1320, Albuquerque, NM 87185 USA. EM ulhetma@sandia.gov; pknupp@sandia.gov NR 31 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 533 EP 550 DI 10.1007/978-3-540-87921-3_32 PG 18 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600032 ER PT B AU Finn, JM Delzanno, GL Chacon, L AF Finn, John M. Delzanno, Gian Luca Chacon, Luis BE Garimella, RV TI Grid Generation and Adaptation by Monge-Kantorovich Optimization in Two and Three Dimensions SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA AB The derivation of the Monge-Ampere (MA) equation, as it results from a variational principle involving grid displacement, is outlined in two dimensions (21)). This equation, a major element of Monge-Kantorovich (MK) optimization, is discussed both in the context of grid generation and grid adaptation. It is shown that grids which are generated by the MA equation also satisfy equations of an alternate variational principle minimizing grid distortion. Numerical results are shown, indicating robustness to grid tangling. Comparison is made with the deformation method [G. Liao and D. Anderson, Appl. Analysis 44, 285 (1992)], the existing method of equidistribution. A formulation is given for more general physical domains, including those with curved boundary segments. The Monge-Ampere equation is also derived in three dimensions (31)). Several numerical examples, both with more general 2D domains and in 3D, are given. C1 [Finn, John M.; Delzanno, Gian Luca; Chacon, Luis] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Finn, JM (reprint author), Los Alamos Natl Lab, T-15,Mail Stop K717, Los Alamos, NM 87545 USA. NR 9 TC 11 Z9 11 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 551 EP 568 DI 10.1007/978-3-540-87921-3_33 PG 18 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600033 ER PT B AU Luo, XJ Shephard, MS Lee, LQ Ng, C Ge, LX AF Luo, Xiaojuan Shephard, Mark S. Lee, Lie-Quan Ng, Cho Ge, Lixin BE Garimella, RV TI Tracking Adaptive Moving Mesh Refinements in 3D Curved Domains for Large-Scale Higher Order Finite Element Simulations SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA ID ADAPTATION AB When applying higher order finite elements to curved 3D domains in large-scale accelerator simulations, complexities that arise include needing valid curved finite elements and the capability to track the movement of mesh refinement in the critical domains. This paper presents a procedure which combines Bezier mesh curving and size driven mesh adaptation technologies to address those requirements. The intelligent selection of local mesh modifications to eliminate invalid curved elements and properly control the size distribution are the two key technical components. The procedure has been successfully applied by SLAC to generate 3D moving curved meshes in the large-scale electromagnetic modeling of next generation accelerator designs. The results demonstrated that valid curvilinear meshes not only make the time domain simulations more reliable but also improve the computational efficiency up to 30%. C1 [Luo, Xiaojuan; Shephard, Mark S.] Rensselaer Polytech Inst, Troy, NY 12180 USA. [Lee, Lie-Quan; Ng, Cho; Ge, Lixin] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Luo, XJ (reprint author), Rensselaer Polytech Inst, Troy, NY 12180 USA. EM xluo@scorec.rpi.edu; shephard@scorec.rpi.edu; liequan@slac.stanford.edu; cho@slac.stanford.edu; lge@slac.stanford.edu FU U.S. Department of Energy under DOE [DE-FC02-06ER25769, DE-AC02-76SF00515] FX This work is supported by U.S. Department of Energy under DOE grant number DE-FC02-06ER25769 and DE-AC02-76SF00515 NR 19 TC 0 Z9 0 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 585 EP + DI 10.1007/978-3-540-87921-3_35 PG 3 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600035 ER PT B AU Woodbury, AC Shepherd, JF Staten, ML Benzley, SE AF Woodbury, Adam C. Shepherd, Jason F. Staten, Matthew L. Benzley, Steven E. BE Garimella, RV TI Localized Coarsening of Conforming All-Hexahedral Meshes SO PROCEEDINGS OF THE 17TH INTERNATIONAL MESHING ROUNDTABLE LA English DT Proceedings Paper CT 17th International Meshing Roundtable CY OCT 12-15, 2008 CL Pittsburgh, PA DE Hexahedral; Mesh; Coarsening; Simplification; Adaptivity; Refinement ID QUALITY METRICS; ADAPTATION; PARALLEL AB Finite element mesh adaptation methods can be used to improve the efficiency and accuracy of solutions to computational modeling problems. In many applications involving hexahedral meshes, localized modifications which preserve a conforming all-hexahedral mesh are desired. Effective hexahedral refinement methods that; satisfy these criteria have recently become available; however, due to hexahedral mesh topology constraints, little progress has been made in the area of hexahedral coarsening. This paper presents a new method to locally coarsen conforming all-hexahedral meshes,. The method works on both structured and unstructured meshes and is not based on undoing previous refinement. Building upon recent developments in quadrilateral coarsening, the method utilizes hexahedral sheet and column operations, including pillowing, column collapsing, and sheet extraction. A general algorithm for automated coarsening is presented and examples of models that have been coarsened with this new algorithm are shown. While results are promising, further work is needed to improve the automated process. C1 [Woodbury, Adam C.; Benzley, Steven E.] Brigham Young Univ, Provo, UT 84602 USA. [Shepherd, Jason F.; Staten, Matthew L.] Sandia Natl Labs, Albuquerque, NM USA. [Staten, Matthew L.] Carnegie Mellon Univ, Pittsburgh, PA USA. RP Benzley, SE (reprint author), Brigham Young Univ, Provo, UT 84602 USA. EM aw18@byu.net; jfsheph@sandia.gov; mlstate@sandia.gov; seb@byu.edu NR 25 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 978-3-540-87920-6 PY 2008 BP 603 EP + DI 10.1007/978-3-540-87921-3_36 PG 3 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA BIR73 UT WOS:000262360600036 ER PT S AU Lereu, AL Sanchez-Mosteiro, G Ghenuche, P Passian, A Quidant, R Garcia-Parajo, M van Hulst, NF AF Lereu, A. L. Sanchez-Mosteiro, G. Ghenuche, P. Passian, A. Quidant, R. Garcia-Parajo, M. van Hulst, N. F. BE Johansson, LSO Andersen, JN Gothelid, M Helmersson, U Montelius, L Rubel, M Setina, J Wernersson, LE TI Probing the local field of nanoantennas using single particle luminescence SO PROCEEDINGS OF THE 17TH INTERNATIONAL VACUUM CONGRESS/13TH INTERNATIONAL CONFERENCE ON SURFACE SCIENCE/INTERNATIONAL CONFERENCE ON NANOSCIENCE AND TECHNOLOGY SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 17th International Vacuum Congress/13th International Conference on Surface Science/International Conference on Nanoscience and Technology CY JUL 02-06, 2007 CL Stockholm, SWEDEN SP Swedish Vacuum Soc ID NANOSTRUCTURES; NANOPARTICLES; LITHOGRAPHY; SCATTERING AB Intense local fields bound to the surface of engineered metallic nanostructures are currently of a great interest for many applications including enhanced imaging, spectroscopy, sensing or lab-on-a-chip devices. Their resonance characteristics can be tuned by the size, shape, incident optical frequency and polarization state. We present here an investigation of the local field of gold dimers manufactured in an array. Finally, employing retarded electrodynamics, we computationally visualize the field distribution and obtain the spectral response of a unique dimer. C1 [Lereu, A. L.; Sanchez-Mosteiro, G.; Ghenuche, P.; Quidant, R.; van Hulst, N. F.] ICFO Inst Ciencias Foton, Barcelona 08860, Spain. [Passian, A.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. [Garcia-Parajo, M.] IBEC Inst Bioengn Catalunya & CIBER, E-08028 Barcelona, Spain. [Quidant, R.; Garcia-Parajo, M.; van Hulst, N. F.] ICREA Inst Catalana Recerca Estudis Acancats, E-08015 Barcelona, Spain. RP Lereu, AL (reprint author), ICFO Inst Ciencias Foton, Barcelona 08860, Spain. EM aude.lereu@icfo.es RI Garcia-Parajo, Maria/I-4610-2015; Lereu, Aude/P-6414-2016; Ghenuche, Petru /J-3535-2012; OI Garcia-Parajo, Maria/0000-0001-6618-3944; Lereu, Aude/0000-0001-7390-7832; Quidant, Romain/0000-0001-8995-8976 FU Specific Target Research Project (STRP) ASPRINT; NoE Plasmo-Nano-Devices in the 6th Framework Program of European Community; ATOM3D [FP6-508952]; PhOREMOST [FP6- 511616]; MOCA [TIC 2003-01038]; [TIC2003-07485] FX This work benefits from the financial support of the Specific Target Research Project (STRP) ASPRINT and the NoE Plasmo-Nano-Devices in the 6th Framework Program of the European Community. This work was also funded by ATOM3D (FP6-508952), PhOREMOST (FP6- 511616), TIC2003-07485, and MOCA (TIC 2003-01038). NR 13 TC 2 Z9 2 U1 2 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 100 AR UNSP 052038 DI 10.1088/1742-6596/100/5/052038 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Coatings & Films; Physics, Applied SC Science & Technology - Other Topics; Materials Science; Physics GA BNV25 UT WOS:000275655200134 ER PT S AU Belkov, SA Kochemasov, GG Kulikov, SM Bondarenko, SV Maslov, NV Rubenchik, A Da Silva, LB AF Belkov, S. A. Kochemasov, G. G. Kulikov, S. M. Bondarenko, S. V. Maslov, N. V. Rubenchik, A. Da Silva, L. B. BE Long, CA Anninos, P Pham, T Anastassopoulos, G Mastorakis, NE TI Analysis of data obtained in optical probing of breast tissue and development of automatic diagnosis algorithm SO PROCEEDINGS OF THE 1ST WSEAS INTERNATIONAL CONFERENCE ON BIOMEDICAL ELECTRONICS AND BIOMEDICAL INFORMATICS SE Recent Advances in Biology and Biomedicine LA English DT Proceedings Paper CT 1st WSEAS International Conference on Biomedical Electronics and Biomedical Informatics CY AUG 20-22, 2008 CL Rhodes, GREECE DE breast cancer diagnostic; optical scattering and absorption spectroscopy; wavelet analysis ID SPECTROSCOPY; REFLECTANCE AB In the clinical trials it was shown, that characteristics of optical scattering and absorption are sensitive to the tissue type and state. System for optical biopsy was tested in the Regional Oncology Center of Nizhny Novgorod, Russia. During a year more than 160 patients with breast tumors were investigated using this system. White light from a xenon lamp was delivered into the breast tissue using special probe with fibers. The radiation scattered from the breast tissue was collected by another fibers and its spectrum was measured. Obtained optical data was analyzed to find general optical characteristics of scattered radiation in different types of tissue and revealing the major peculiarities in the spectral scattering coefficients of malignant tumors and their distinctions from benign tumors and healthy tissue. Using different mathematical algorithm the typical template of scattering spectrum was found for benign and malignant type of breast tumor. Then the algorithm of automatic detection of malignant spectra in the data flow was developed. Using this algorithm the datasets of all patients were processed and analyzed and the diagnoses were obtained. The automatic diagnoses were compared with those given by physicians. As a result the indexes of sensitivity and specificity for the optical biopsy diagnostic method were found equal to 91% and 90% correspondingly. C1 [Belkov, S. A.; Kochemasov, G. G.; Kulikov, S. M.; Bondarenko, S. V.; Maslov, N. V.] BioFil Biophys Lab, Sarov, Russia. [Rubenchik, A.] LLNL, Livermore, CA USA. [Da Silva, L. B.] BioIntelligent Inc, Livermore, CA USA. RP Belkov, SA (reprint author), BioFil Biophys Lab, Sarov, Russia. FU IPP (Initiatives for Proliferation Prevention) Program of U.S. Department of Energy [LLNL-T2-0242-RU]; International Science and Technology Center [3075p] FX This work was partly supported by funding of IPP (Initiatives for Proliferation Prevention) Program of U.S. Department of Energy under the contract LLNL-T2-0242-RU and the Project #3075p of International Science and Technology Center. NR 7 TC 0 Z9 0 U1 0 U2 2 PU WORLD SCIENTIFIC AND ENGINEERING ACAD AND SOC PI ATHENS PA AG LOANNOU THEOLOGOU 17-23, 15773 ZOGRAPHOU, ATHENS, GREECE SN 1790-5125 BN 978-960-6766-93-0 J9 REC ADV BIOL BIOMED PY 2008 BP 35 EP + PG 3 WC Engineering, Biomedical; Mathematical & Computational Biology SC Engineering; Mathematical & Computational Biology GA BIK87 UT WOS:000260437900003 ER PT S AU Belkov, SA Garanin, SG Kochemasov, GG Kulikov, SM Chernopyatov, VY Shakhova, NM Rubenchik, A Da Silva, LB AF Belkov, S. A. Garanin, S. G. Kochemasov, G. G. Kulikov, S. M. Chernopyatov, V. Ya. Shakhova, N. M. Rubenchik, A. Da Silva, L. B. BE Long, CA Anninos, P Pham, T Anastassopoulos, G Mastorakis, NE TI Studies of optical probe for breast cancer diagnostics performed in Regional Oncology Center of Nizhny Novgorod SO PROCEEDINGS OF THE 1ST WSEAS INTERNATIONAL CONFERENCE ON BIOMEDICAL ELECTRONICS AND BIOMEDICAL INFORMATICS SE Recent Advances in Biology and Biomedicine LA English DT Proceedings Paper CT 1st WSEAS International Conference on Biomedical Electronics and Biomedical Informatics CY AUG 20-22, 2008 CL Rhodes, GREECE DE Breast cancer; optical biopsy system; spectrometry of scattered radiation ID SCATTERING; SPECTROSCOPY; REFLECTANCE AB An optical biopsy system for early breast cancer diagnostics is reported. This system has a special invasive probe that can deliver the light from xenon lamp into the breast tissue. The scattered light collects by several fibers that were placed into the same probe. The spectrum of scattered light was measured by spectrometers in real time. During last two years the system was tested in the Regional Oncology Center of Nizhny Novgorod, Russia. More then 160 patents were investigated using this system. After optical biopsy the usual fine biopsy procedure were performed and cytological analysis of tumor cell samples was conducted. The clinical tests have found that the holder has some limitations of its design as it exists today. New design of the probe was proposed and now its clinical test was began. C1 [Belkov, S. A.; Garanin, S. G.; Kochemasov, G. G.; Kulikov, S. M.; Chernopyatov, V. Ya.] BioFil Ltd, Biophys Lab, Nizhny, Novgorod Reg, Russia. [Shakhova, N. M.] Russian Acad Sci, Inst Appl Phys, Nizhnii Novgorod, Russia. [Rubenchik, A.] LLNL, Livermore, CA USA. [Da Silva, L. B.] BioTelligent Inc, Livermore, CA USA. RP Belkov, SA (reprint author), BioFil Ltd, Biophys Lab, Nizhny, Novgorod Reg, Russia. FU IPP (Initiatives for Proliferation Prevention) Program of U.S. Department of Energy [LLNL-T2-0242-RU]; International Science and Technology Center [3075p] FX This work was partly supported by funding of IPP (Initiatives for Proliferation Prevention) Program of U.S. Department of Energy under the contract LLNL-T2-0242-RU and the Project #3075p of International Science and Technology Center. NR 6 TC 0 Z9 0 U1 0 U2 2 PU WORLD SCIENTIFIC AND ENGINEERING ACAD AND SOC PI ATHENS PA AG LOANNOU THEOLOGOU 17-23, 15773 ZOGRAPHOU, ATHENS, GREECE SN 1790-5125 BN 978-960-6766-93-0 J9 REC ADV BIOL BIOMED PY 2008 BP 41 EP + PG 2 WC Engineering, Biomedical; Mathematical & Computational Biology SC Engineering; Mathematical & Computational Biology GA BIK87 UT WOS:000260437900004 ER PT S AU Cisorio, I Gopalsami, N Kochemasov, G Kulikov, S Baranov, V Eroshenko, V Lyubynskaya, T AF Cisorio, I Gopalsami, N. Kochemasov, G. Kulikov, S. Baranov, V Eroshenko, V Lyubynskaya, T. BE Long, CA Anninos, P Pham, T Anastassopoulos, G Mastorakis, NE TI Development of Closed-Loop Implantable Cooling System for Epileptic Seizure Blockage SO PROCEEDINGS OF THE 1ST WSEAS INTERNATIONAL CONFERENCE ON BIOMEDICAL ELECTRONICS AND BIOMEDICAL INFORMATICS SE Recent Advances in Biology and Biomedicine LA English DT Proceedings Paper CT 1st WSEAS International Conference on Biomedical Electronics and Biomedical Informatics CY AUG 20-22, 2008 CL Rhodes, GREECE DE epilepsy; seizure blockage; closed-loop system; implant; brain minicooler; SAW-sensor; telemetry system AB Hardware development and laboratory tests of an implantable closed-loop system for epileptic seizure blockage are reported. This approach (thermal suppression of abnormal brain electrical activity) is based on evidence derived mainly from animals and anecdotal reports from humans. An array of 7 needle-like probes (outer diameter similar to 1 nim; length similar to 20 mm) along with a SAW temperature sensor was designed using computer modeling for rapid (similar to 30 sec) cooling (similar to 37 degrees C to similar to 16 degrees C) of cubic inch of brain tissue (approximately the volume of the human amygdala and pes hippocampus). Theoretical studies and numerical modeling based on Pennes' equation were performed to optimize regional brain cooling. Experimental tests demonstrated good agreement with calculations. Changes in regional brain temperature associated with the onset of seizures are detected via the SAW sensor probe, automatically activating the cooling device for rapid lowering of regional temperature. The cooling device and implantable SAW-sensor will be integrated with a telemetry controlling system with signal processing, seizure detection, decision-making, and triggering functions. The telemetry system is under development. C1 [Cisorio, I] Flint Hills Sci, Lawrence, KS 66044 USA. [Gopalsami, N.] Argonne Natl Lab, Argonne, IL 60439 USA. [Kochemasov, G.; Kulikov, S.; Baranov, V; Eroshenko, V; Lyubynskaya, T.] Russian Fed Nucl Ctr, VNIIEF, BioFil Biophys Lab, Nizhnii Novgorod 607200, Russia. RP Cisorio, I (reprint author), Flint Hills Sci, Lawrence, KS 66044 USA. EM tlyubyn@gmail.com FU GIPP (Global Initiatives for Proliferation Prevention) Program of U.S. Department of Energy [ANL-T2-214A] FX This work was supported by funding from GIPP (Global Initiatives for Proliferation Prevention) Program of U.S. Department of Energy under the contract ANL-T2-214A NR 7 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC AND ENGINEERING ACAD AND SOC PI ATHENS PA AG LOANNOU THEOLOGOU 17-23, 15773 ZOGRAPHOU, ATHENS, GREECE SN 1790-5125 BN 978-960-6766-93-0 J9 REC ADV BIOL BIOMED PY 2008 BP 80 EP + PG 2 WC Engineering, Biomedical; Mathematical & Computational Biology SC Engineering; Mathematical & Computational Biology GA BIK87 UT WOS:000260437900010 ER PT B AU El-Hannouny, E Longman, D McConnell, S Xie, XB Lai, MC Poola, R Goetzke, M AF El-Hannouny, Essam Longman, Douglas McConnell, Steven Xie, Xingbin Lai, Ming-Chai Poola, Ramesh Goetzke, Michael GP ASME TI Spray characterization from common rail injection system for use in locomotive engines SO PROCEEDINGS OF THE 2007 FALL TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT Fall Technical Conference of the ASME Internal Combustion Engine Division CY OCT 14-17, 2007 CL Charleston, SC SP Amer Soc Mech Engineers AB New U.S. Environmental Protection Agency regulations are forcing locomotive manufacturers and railroads to reduce pollutant emissions from locomotive operation. Locomotive engines will be required to meet the applicable standards at the time of original manufacture. A variety of emissions-reduction technologies can be used, such as alternative fuels, additives in lubricant oil, and aftertreatment technologies (e.g., selective catalytic reduction and particulate traps). Emissions reduction can also be accomplished inside the cylinder, using advanced diesel fuel injectors that have a significant impact on the quality of spray and charge preparation before engine combustion and subsequent events. High-speed optical measurements have been collected at elevated ambient pressures for sprays from a modular common rail injection system at Argonne National Laboratory in order to investigate spray structure and dynamics. High-speed laser imaging was used to explore the effects of various parameters on the spray structure. The experimental parameters included were ambient gas density, injection pressure, number of spray holes, injection strategy, and internal orifice size. Spray symmetry and structure were found to depend significantly on the nozzle geometry or manufacturing variances and the operating conditions. C1 [El-Hannouny, Essam; Longman, Douglas; McConnell, Steven] Argonne Natl Lab, Ctr Transportat Res, Argonne, IL 60439 USA. RP El-Hannouny, E (reprint author), Argonne Natl Lab, Ctr Transportat Res, Argonne, IL 60439 USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4811-1 PY 2008 BP 85 EP 115 PG 31 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHM24 UT WOS:000254225700009 ER PT B AU Kastengren, AL Powell, CF Wang, YJ Wang, J AF Kastengren, A. L. Powell, C. F. Wang, Y. -J. Wang, J. GP ASME TI Study of diesel jet variability using single-shot X-ray radiography SO PROCEEDINGS OF THE 2007 FALL TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT Fall Technical Conference of the ASME Internal Combustion Engine Division CY OCT 14-17, 2007 CL Charleston, SC SP Amer Soc Mech Engineers AB The variability of diesel jet structure, both as a function of time and between individual injection events, has important implications on the breakup and mixing of the jet. It is accepted that diesel jets become unstable due to interactions with the ambient gas, leading to breakup of the jet. This concept is the principle behind the Kelvin-Helmholtz and Rayleigh-Taylor models of diesel atomization. Very little information regarding diesel jet variability is available, however, in the near-nozzle region of the diesel jet, where primary breakup of the jet occurs. This is due to the presence of many small droplets, which strongly scatter visible light and render the spray opaque. X-ray radiography has been successfully used in recent years to probe the structure of diesel sprays with high spatial and temporal resolution. All of these previous measurements, however, were ensemble-averaged, measuring only persistent features of the spray. In the current study, measurements are performed at individual measurement points of single diesel injection events. These measurements are taken at several points near the injector exit for a non-hydroground nozzle with a single axial hole at two injection pressures (500 and 1000 bar). The variability of the start of injection, end of injection, and the time history of the spray density during the injection event are examined, as well as how these quantities change for different transverse positions across the jet. C1 [Kastengren, A. L.; Powell, C. F.] Argonne Natl Lab, Ctr Transportat Res, Argonne, IL 60439 USA. RP Kastengren, AL (reprint author), Argonne Natl Lab, Ctr Transportat Res, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4811-1 PY 2008 BP 155 EP 162 PG 8 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHM24 UT WOS:000254225700013 ER PT B AU Daw, CS Edwards, KD Wagner, RM Green, JB AF Daw, C. Stuart Edwards, K. Dean Wagner, Robert M. Green, Johney B., Jr. GP ASME TI Modeling cyclic variability in spark-assisted HCCI SO PROCEEDINGS OF THE 2007 FALL TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT Fall Technical Conference of the ASME Internal Combustion Engine Division CY OCT 14-17, 2007 CL Charleston, SC SP Amer Soc Mech Engineers AB Spark assist appears to offer considerable potential for increasing the speed and load range over which homogeneous charge compression ignition (HCCI) is possible in gasoline engines. Numerous experimental studies of the transition between conventional spark-ignited (SI) propagating-flame combustion and HCCI combustion in gasoline engines with spark assist have demonstrated a high degree of deterministic coupling between successive combustion events. Analysis of this coupling suggests that the transition between SI and HCCI can be described as a sequence of bifurcations in a low-dimensional dynamic map. In this paper we describe methods for utilizing the deterministic relationship between cycles to extract global kinetic rate parameters that can be used to discriminate multiple distinct combustion states and develop a more quantitative understanding of the SI-HCCI transition. We demonstrate the application of these methods for indolene-containing fuels and point out an apparent HCCI mode switching not previously reported. Our results have specific implications for developing dynamic combustion models and feedback control strategies that utilize spark-assist to expand the operating range of HCCI combustion. C1 [Daw, C. Stuart; Edwards, K. Dean; Wagner, Robert M.; Green, Johney B., Jr.] Fuels Engines & Emiss Res Ctr, Oak Ridge Natl Lab, Knoxville, TN 37932 USA. RP Daw, CS (reprint author), Fuels Engines & Emiss Res Ctr, Oak Ridge Natl Lab, 2360 Cherahala Blvd, Knoxville, TN 37932 USA. NR 17 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4811-1 PY 2008 BP 185 EP 192 PG 8 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHM24 UT WOS:000254225700016 ER PT B AU Lachaux, T Musculus, MPB Singh, S Reitz, RD AF Lachaux, Thierry Musculus, Mark P. B. Singh, Satbir Reitz, Rolf D. GP ASME TI Optical diagnostics of late injection low-temperature combustion in a heavy duty diesel engine SO PROCEEDINGS OF THE 2007 FALL TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT Fall Technical Conference of the ASME Internal Combustion Engine Division CY OCT 14-17, 2007 CL Charleston, SC SP Amer Soc Mech Engineers AB A late injection, high exhaust-gas recirculation (EGR)-rate, low-temperature combustion strategy was investigated in a heavy-duty diesel engine using a suite of optical diagnostics: chemiluminescence for visualization of ignition and combustion, laser Mie scattering for liquid fuel imaging, planar laser-induced fluorescence (PLIF) for both OH and vapor-fuel imaging, and laser-induced incandescence (LII) for soot imaging. Fuel is injected at top dead center when the in-cylinder gases are hot and dense. Consequently, the maximum liquid fuel penetration is 27 mm, which is short enough to avoid wall impingement. The cool flame starts 4.5 crank angle degrees (CAD) after the start of injection (ASI), midway between the injector and bowl-rim, and likely helps fuel to vaporize. Within a few CAD, the cool-flame combustion reaches the bowl-rim. A large premixed combustion occurs near 9 CAD ASI, close to the bowl rim. Soot is visible shortly afterwards along the walls, typically between two adjacent jets at the head vortex location. OH PLIF indicates that premixed combustion first occurs within the jet and then spreads along the bowl rim in a thin layer, surrounding soot pockets at the start of the mixing-controlled combustion phase near 17 CAD ASI. During the mixing-controlled phase, soot is not fully oxidized and is still present near the bowl-rim late in the cycle. At the end of combustion near 27 CAD ASI, averaged PLIF images indicate two separate zones. OH PLIF appears near the bowl rim, while broadband PLIF persists late in the cycle near the injector. The most likely source of broadband PLIF is unburned fuel, which indicates that the near-injector region is a potential source of unburned hydrocarbons. C1 [Lachaux, Thierry; Musculus, Mark P. B.] Sandia Natl Labs, Livermore, CA 94551 USA. RP Lachaux, T (reprint author), Sandia Natl Labs, POB 969,MS9053, Livermore, CA 94551 USA. NR 35 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4811-1 PY 2008 BP 253 EP 263 PG 11 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHM24 UT WOS:000254225700022 ER PT B AU Miers, SA Kastengren, AL EI-Hannouny, EM Longman, DE AF Miers, Scott A. Kastengren, Alan L. EI-Hannouny, Essam M. Longman, Douglas E. GP ASME TI An experimental investigation of biodiesel injection characteristics using a light-duty diesel injector SO PROCEEDINGS OF THE 2007 FALL TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT Fall Technical Conference of the ASME Internal Combustion Engine Division CY OCT 14-17, 2007 CL Charleston, SC SP Amer Soc Mech Engineers AB The objective of this research was to experimentally evaluate the effects of two biodiesel fuels with different viscosities on fuel injection characteristics using a light-duty, common-rail, diesel injection system. A pure biodiesel (B100) and a 50/50 blend of pure biodiesel and refined, bleached, and deodorized vegetable oil (B50V50) were compared with a laboratory diesel fuel equivalent (D100). The fuel viscosity ranged from 2.6 cSt (D100) to 10.9 cSt (B50V50). Three injection pressures and two injector nozzle geometries and surface finishes were also investigated. Measurements of the injected fuel quantity showed that as fuel viscosity increased, the injected volume decreased and the variability in the injected volume tended to increase. This effect was more significant in an injector nozzle with converging, highly hydro-ground holes than one with straight, lightly hydro-ground holes. The rate-of-injection (ROI) data were quite similar for D100 and B100 when using the straight, lightly hydro-ground nozzle. There is a marked reduction in peak injection rate for the B100, compared to D100, when the highly hydro-ground nozzle was utilized. With both nozzles, the B50V50 blend produced narrower ROI curves with peak injection rates equal to or exceeding those of D100 fuel. For all three fuels, the start-of-injection delay increased as fuel viscosity increased. The end-of-injection time was very similar for D100 and B100 but was advanced for the B50V50 blend. C1 [Miers, Scott A.; Kastengren, Alan L.; EI-Hannouny, Essam M.; Longman, Douglas E.] Argonne Natl Lab, Argonne, IL 60439 USA. RP Miers, SA (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. NR 20 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4811-1 PY 2008 BP 311 EP 319 PG 9 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHM24 UT WOS:000254225700027 ER PT B AU Parks, JE AF Parks, James E., II GP ASME TI Mitigation of sulfur effects on a lean NOx trap catalyst by sorbate reapplication SO PROCEEDINGS OF THE 2007 FALL TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT Fall Technical Conference of the ASME Internal Combustion Engine Division CY OCT 14-17, 2007 CL Charleston, SC SP Amer Soc Mech Engineers AB Lean NOx trap catalysis has demonstrated the ability to reduce NOx emissions from lean natural gas reciprocating engines by >90%. The technology operates in a cyclic fashion where NOx is trapped on the catalyst during lean operation and released and reduced to N(2) under rich exhaust conditions; the rich cleansing operation of the cycle is referred to as "regeneration" since the catalyst is reactivated for more NOx trapping. Natural gas combusted over partial oxidation catalysts in the exhaust can be used to obtain the rich exhaust conditions necessary for catalyst regeneration. Thus, the lean NOx trap technology is well suited for lean natural gas engine applications. One potential limitation of the lean NOx trap technology is sulfur poisoning. Sulfur compounds directly bond to the NOx trapping sites of the catalyst and render them ineffective; over time, the sulfur poisoning leads to degradation in overall NOx reduction performance. In order to mitigate the effects of sulfur poisoning, a process has been developed to restore catalyst activity after sulfur poisoning has occurred. The process is an aqueous-based wash process that removes the poisoned sorbate component of the catalyst. A new sorbate component is reapplied after removal of the poisoned sorbate. The process is low cost and does not involve reapplication of precious metal components of the catalyst. Experiments were conducted to investigate the feasibility of the washing process on a lean 8.3-liter natural gas engine on a dynamometer platform. The catalyst was rapidly sulfur poisoned with bottled SO(2) gas; then, the catalyst sorbate was washed and reapplied and performance was reevaluated. Results show that the sorbate reapplication process is effective at restoring lost performance due to sulfur poisoning. Specific details relative to the implementation of the process for large stationary natural gas engines will be discussed. C1 Oak Ridge Natl Lab, Knoxville, TN 37932 USA. RP Parks, JE (reprint author), Oak Ridge Natl Lab, 2360 Cherahala Blvd, Knoxville, TN 37932 USA. NR 16 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4811-1 PY 2008 BP 423 EP 434 PG 12 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHM24 UT WOS:000254225700037 ER PT B AU Lin, HT Brady, MP Kass, MD Theiss, TJ Domingo, N Levina, I Lykowski, J AF Lin, H. T. Brady, M. P. Kass, M. D. Theiss, T. J. Domingo, N. Levina, I. Lykowski, J. GP ASME TI Characterization and mitigation of spark plug electrode erosion in natural gas and automotive engine applications SO PROCEEDINGS OF THE 2007 FALL TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT Fall Technical Conference of the ASME Internal Combustion Engine Division CY OCT 14-17, 2007 CL Charleston, SC SP Amer Soc Mech Engineers ID NITROGEN; CHROMIUM AB Microstructural characterization was conducted for laboratory gasoline and natural gas reciprocating engine tested spark plug electrodes made from a range of model, developmental, and commercially available electrode alloys. These alloys were selected to explore the effects of differing electrode alloy thermal, chemical, and mechanical characteristics on erosion resistance, and were tested with and without sparking surface alloy insert pads (platinum group and novel Cr-based alloys). Extensive internal oxidation and cracking were observed in both gasoline and natural gas engine tests, indicative of an inherent degree of susceptibility of currently-used electrode materials when heated to elevated temperatures, no matter what the ignition conditions. Highly-alloyed heat-resistant alloys with excellent oxidation resistance in many high-temperature environments suffered from increased rates of erosion, as the gains in oxidation resistance appear to have been offset by hotter running temperatures resulting from decreased electrode alloy thermal conductivity. Promising early results were obtained with a novel Cr-6MgO(0.5)Ti(-0.3)La(2)O(3) insert pad electrode alloy, investigated as an alternative to Pt- or Ir- base alloys, which showed little erosion and good resistance to cracking and oxidation. C1 [Lin, H. T.; Brady, M. P.; Kass, M. D.; Theiss, T. J.; Domingo, N.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lin, HT (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Brady, Michael/A-8122-2008 OI Brady, Michael/0000-0003-1338-4747 NR 16 TC 0 Z9 0 U1 2 U2 5 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4811-1 PY 2008 BP 675 EP 683 PG 9 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHM24 UT WOS:000254225700064 ER PT B AU Blazewicz, J Bryja, M Figlerowicz, M Gawron, P Kasprzak, M Platt, D Przybytek, J Swiercz, A Szajkowski, L AF Blazewicz, Jacek Bryja, Marcin Figlerowicz, Marek Gawron, Piotr Kasprzak, Marta Platt, Darren Przybytek, Jakub Swiercz, Aleksandra Szajkowski, Lukasz BE Stepnowski, A Moszynski, M Kochanski, T Dabrowski, J TI A new algorithm for genome assembly from short reads SO PROCEEDINGS OF THE 2008 1ST INTERNATIONAL CONFERENCE ON INFORMATION TECHNOLOGY LA English DT Proceedings Paper CT 1st International Conference on Information Technology (IT 2008) CY MAY 19-21, 2008 CL Gdansk Univ Technol, Fac Elect, Telecommun & Informat, Gdansk, POLAND SP IEEE HO Gdansk Univ Technol, Fac Elect, Telecommun & Informat ID DNA; ERRORS AB Progress in bioengineering brought a new approach to DNA sequencing, which aim is to give highly reliable output of low cost and in short time. It is 454 sequencing, based on the pyrosequencing protocol, owned by 454 Life Sciences Corporation. Because of the sequences reliability this method is much better than others for assembly purposes. However, produced sequences are much shorter and there are many more of them, which indicate that the problem is harder. Presented algorithm was created to process data from 454 sequencing method. Usefulness of the algorithm has been proven in tests on raw data generated during sequencing of the whole 1.84 Mbp genome of bacteria Prochlorococcus marinus. C1 [Blazewicz, Jacek; Bryja, Marcin; Gawron, Piotr; Kasprzak, Marta; Przybytek, Jakub; Swiercz, Aleksandra] Poznan Univ Tech, Inst Comp Sci, Piotrowo 2, PL-60965 Poznan, Poland. [Platt, Darren; Szajkowski, Lukasz] Lawrence Livermore Natl Lab, Joint Genome Inst, Livermore, CA 94550 USA. [Blazewicz, Jacek; Figlerowicz, Marek; Kasprzak, Marta; Swiercz, Aleksandra] Polish Acad Sci, Inst Bioorgan Chem, Poznan, Poland. RP Blazewicz, J (reprint author), Poznan Univ Tech, Inst Comp Sci, Piotrowo 2, PL-60965 Poznan, Poland. EM piotr.gawron@cs.put.poznan.pl RI Kasprzak, Marta/H-9242-2012; Swiercz, Aleksandra/K-6507-2014; Blazewicz, Jacek/L-5597-2014; Figlerowicz, Marek/B-9550-2015 OI Blazewicz, Jacek/0000-0001-8326-1094; NR 13 TC 0 Z9 0 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 978-1-4244-2244-9 PY 2008 BP 455 EP + PG 2 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIF24 UT WOS:000259080600105 ER PT B AU Yu, W Rao, N Vetter, J AF Yu, Weikuan Rao, Nageswara Vetter, Jeffrey GP IEEE Computer Society TI Experimental analysis of InfiniBand transport services on WAN SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL CONFERENCE ON NETWORKING, ARCHITECTURE, AND STORAGE LA English DT Proceedings Paper CT IEEE International Conference on Networking, Architecture, and Storage CY JUN 12-14, 2008 CL Chongqing, PEOPLES R CHINA SP IEEE Tech Comm Parallel Proc, IEEE Tech Comm Distributed Proc, IEEE Comp Soc, IEEE, Chongqing Univ, HuaZhong Univ Sci & Technol ID PERFORMANCE; NETWORK AB InfiniBand Architecture (IBA) has emerged as a standard system-area interconnect in industry for both datacenter and high performance computing. While IBA continues to evolve with more capabilities, it has yet to permeate the field of grid and pervasive computing across wide area. This requires a software infrastructure to take the full advantage of 1BA networking mechanisms without being dwarfed by the long distances. In this paper, we present a detailed analysis of InfiniBand transport services for their suitability to data transfer and message passing in the wide area. Three of the common InfiniBand transport services have been examined, including Reliable Connection (RC), Unreliable Connection (UQ, and Unreliable Datagram (UD). Our analysis indicates that UC and UD are better suited to provide high bandwidth for MPI on wide-area networks (WAN). We have also demonstrated that the current existing MPI implementations, designed over RC and UD, can be tuned to provide improved MPI bandwidth on WAN. Furthermore, by developing a UC-based MPI implementation, we have shown that, at a distance of 8600 miles, MPI over UC can improve MPI bandwidth by as much as 100%. C1 [Yu, Weikuan; Rao, Nageswara; Vetter, Jeffrey] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Yu, W (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Rao, Nageswara/0000-0002-3408-5941 NR 18 TC 1 Z9 1 U1 0 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3187-8 PY 2008 BP 233 EP 240 PG 8 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIB61 UT WOS:000258182400042 ER PT B AU Chen, J Watson, W AF Chen, Jie Watson, William, III GP IEEE Computer Society TI Software barrier performance on dual quad-core Opterons SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL CONFERENCE ON NETWORKING, ARCHITECTURE, AND STORAGE LA English DT Proceedings Paper CT IEEE International Conference on Networking, Architecture, and Storage CY JUN 12-14, 2008 CL Chongqing, PEOPLES R CHINA SP IEEE Tech Comm Parallel Proc, IEEE Tech Comm Distributed Proc, IEEE Comp Soc, IEEE, Chongqing Univ, HuaZhong Univ Sci & Technol AB Multi-core processors based SMP servers have become building blocks for Linux clusters in recent years because they can deliver better performance for multi-threaded programs through on-chip multi-threading. However a relative slow software barrier can hinder the performance of a data-parallel scientific application on a multi-core system. In this paper we study the performance of different software barrier algorithms on a server based on newly introduced AMD quad-core Opteron processors. We study how the memory architecture and the cache coherence protocol of the system influence the performance of barrier algorithms. We present an optimized barrier algorithm derived from the queue-based barrier algorithm. We find that the optimized barrier algorithm achieves speedup of 1.77 over the original queue-based algorithm. In addition, it has speedup of 2.39 over the software barrier generated by the Intel OpenMP compiler. C1 [Chen, Jie; Watson, William, III] Jefferson Lab, Sci Comp Grp, Newport News, VA 23606 USA. RP Chen, J (reprint author), Jefferson Lab, Sci Comp Grp, Newport News, VA 23606 USA. EM chen@jlab.org; watson@jlab.org NR 15 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3187-8 PY 2008 BP 303 EP 309 DI 10.1109/NAS.2008.27 PG 7 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIB61 UT WOS:000258182400051 ER PT S AU Tully, LK Fulkerson, ES Goerz, DA Speer, RD AF Tully, L. K. Fulkerson, E. S. Goerz, D. A. Speer, R. D. BE Kirkici, H TI Evaluation of Light-Triggered Thyristors for Pulsed Power Applications SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB Lawrence Livermore National Laboratory has many needs for high reliability, high peak current, high di/dt switches. Solid-state switch technology offers the demonstrated advantage of reliability under a variety of conditions. Light-triggered switches operate with a reduced susceptibility to electromagnetic interference commonly found within pulsed power environments. Despite the advantages, commercially available solid-state switches arc not typically designed for the often extreme pulsed power requirements. Testing was performed to bound the limits of devices for pulsed power applications beyond the manufacturers' specified ratings. To test the applicability of recent commercial light-triggered solid-state designs, an adjustable high current switch test stand was assembled. Results from testing and subsequent selected implementations arc presented. C1 [Tully, L. K.; Fulkerson, E. S.; Goerz, D. A.; Speer, R. D.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Tully, LK (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 1 EP 4 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400001 ER PT S AU Javedani, JB Houck, TL Kelly, BT Lahowe, DA Shirk, MD Goerz, DA AF Javedani, J. B. Houck, T. L. Kelly, B. T. Lahowe, D. A. Shirk, M. D. Goerz, D. A. BE Kirkici, H TI UV Induced Insulator Flashover SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB Insulators are critical components in high-energy, pulsed power systems. It is known that the vacuum surface of the insulator will flashover when illuminated by ultraviolet (UV) radiation depending on the insulator material, insulator cone angle, applied voltage and insulator shot-history. A testbed comprised of an excimer laser (KrF, 248 nm, similar to 2 MW/cm(2), 30 ns FWHM,), a vacuum chamber (low 1.0E-6 torr), and dc high voltage power supply (<60 kV) was assembled for insulator testing to measure the UV dose during a flashover event. Five in-house developed and calibrated fast D-Dot probes (>12 GHz, bandwidth) were embedded in the anode electrode underneath the insulator to determine the time of flashover with respect to UV arrival. A commercial energy meter were used to measure the UV fluence for each pulse. Four insulator materials High Density Polyethylene, Rexolite(R) 1400, Macor (TM) and Mycalex with side- angles of 0, +/- 30, and +/- 45 degrees, 1.0 cm thick samples, were tested with a maximum UV fluence of 75 mJ/cm(2) and at varying electrode charge (10 kV to 60 kV). This information clarified/corrected earlier published studies. A new phenomenon was observed related to the UV power level on flashover that as the UV pulse intensity was increased, the UV fluence on the insulator prior to flashover was also increased. This effect would bias the data towards higher minimum flashover fluence. C1 [Javedani, J. B.; Houck, T. L.; Kelly, B. T.; Lahowe, D. A.; Shirk, M. D.; Goerz, D. A.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Javedani, JB (reprint author), Lawrence Livermore Natl Lab, L-154,7000 East Ave, Livermore, CA 94550 USA. EM javedani1@llnl.gov NR 4 TC 5 Z9 8 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 33 EP 36 DI 10.1109/IPMC.2008.4743569 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400009 ER PT S AU Wilson, MP Given, MJ MacGregor, SJ Timoshkin, IV Beveridge, JR Thomas, KJ Sinclair, MA Lehr, JM AF Wilson, M. P. Given, M. J. MacGregor, S. J. Timoshkin, I. V. Beveridge, J. R. Thomas, K. J. Sinclair, M. A. Lehr, J. M. BE Kirkici, H TI Breakdown Initiation Fields for Surface Flashover of Dielectric Materials Immersed in Transformer Oil SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB The applied electrical fields required to initiate surface flashover of different types of polymeric insulating material immersed in transformer oil have been investigated. Cylindrical samples of polypropylene, ultra-high molecular weight polyethylene, low-density polyethylene, and Rexolite were tested. Average electrical fields up to similar to 700 kV/cm were applied to samples via a 10-stage, inverting Marx generator. The samples were held between two electrodes immersed in 20 litres of EOS Ltd. (UK) L10B transformer oil. The stage capacitance of the Marx is 80 nF, and the rise time is around 100 ns with the test cell load. The applied electrical field required to initiate surface flashover was found by firing the system with an increasing charging voltage until a breakdown occurred. Experiments were performed with plane-plane electrodes and two types of point-plane electrode gap. The first point-plane gap was achieved by deploying a high-voltage electrode with a 1-mm-diameter pin protruding perpendicular to the surface, and the second by a high-voltage electrode with a 25-mm-diameter collar centred on the surface. Of the materials tested, polypropylene showed the highest average peak applied fields to initiate the first surface flashover, varying from 325 kV/cm in non-uniform fields to 637 kV/cm in uniform fields. C1 [Wilson, M. P.; Given, M. J.; MacGregor, S. J.; Timoshkin, I. V.; Beveridge, J. R.] Univ Strathclyde, Inst Energy & Environm, Royal Coll Bldg,204 George St, Glasgow G1 1XW, Lanark, Scotland. [Thomas, K. J.; Sinclair, M. A.] AWE Aldermaston, Pulsed Power Grp, H36, Reading RG7 4PR, Berks, England. [Lehr, J. M.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wilson, MP (reprint author), Univ Strathclyde, Inst Energy & Environm, Royal Coll Bldg,204 George St, Glasgow G1 1XW, Lanark, Scotland. OI Wilson, Mark/0000-0003-3088-8541 FU AWE FX The primary author would like to thank AWE for financial support of the study. NR 4 TC 1 Z9 1 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 41 EP + DI 10.1109/IPMC.2008.4743571 PG 2 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400011 ER PT S AU Savage, M LeChien, K Stygar, W Maenchen, J McDaniel, D Struve, K AF Savage, Mark LeChien, Keith Stygar, William Maenchen, John McDaniel, Dillon Struve, Kenneth BE Kirkici, H TI OVERVIEW AND STATUS OF THE UPGRADED Z PULSED POWER DRIVER SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc C1 [Savage, Mark; LeChien, Keith; Stygar, William; Maenchen, John; McDaniel, Dillon; Struve, Kenneth] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Savage, M (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 1 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 93 EP 93 DI 10.1109/IPMC.2008.4743586 PG 1 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400026 ER PT S AU Struve, KW Bennett, LF Chavez, TF Davis, JP Haijes, HC Pasik, M Savage, ME Smith, DL Stygar, WA Wagoner, TC AF Struve, K. W. Bennett, L. F. Chavez, T. F. Davis, J. P. Haijes, H. C. Pasik, M. Savage, M. E. Smith, D. L. Stygar, W. A. Wagoner, T. C. BE Kirkici, H TI Circuit-Code Modeling of the Refurbished Z Accelerator: Comparison of Measurements with Predictions SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB With the successful completion of its refurbishment the Z machine at Sandia is now routinely operating with currents over 26 MA into various loads. Now that the machine is operating we can measure current and voltage at various locations throughout the machine and compare with circuit code predictions. These measurements have led to improvements in the model that provide a more accurate predictive capability. In this paper we describe the fun-machine circuit model of Z, and indicate how machine parameters are derived. Many were determined with commercially-available field calculation software, but parameters for switches and other non-linear elements were determined empirically. We show comparisons of circuit code predictions with machine performance. Finally, we show where improvements to the model can yet be made. C1 [Struve, K. W.; Bennett, L. F.; Chavez, T. F.; Davis, J. P.; Haijes, H. C.; Pasik, M.; Savage, M. E.; Smith, D. L.; Stygar, W. A.; Wagoner, T. C.] Sandia Natl Labs, Albuquerque, NM 87123 USA. RP Struve, KW (reprint author), Sandia Natl Labs, 1515 Eubank SE, Albuquerque, NM 87123 USA. NR 14 TC 3 Z9 3 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 94 EP 97 DI 10.1109/IPMC.2008.4743587 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400027 ER PT S AU Leckbee, J Cordova, S Oliver, B Johnson, DL Toury, M Rosol, R Bui, B AF Leckbee, Joshua Cordova, Steve Oliver, Bryan Johnson, David L. Toury, Martial Rosol, Rodolphe Bui, Bill BE Kirkici, H TI Load Line Evaluation of a 1-MV Linear Transformer Driver (LTD) SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc ID RADIOGRAPHY AB A seven cavity LTD system has been assembled and tested in a voltage adder configuration capable of producing approximately 1-MV into a 7-Omega, critically damped load. Individual cavities have been tested with a resistive load. The seven cavity adder has been tested with a large area electron beam diode. The output pulse when tested into a resistive load is that of an RLC circuit. When tested with a dynamic load impedance, the output voltages of the cavities have an added oscillation. The oscillation affects the output pulse shape but is not harmful to the cavity components. C1 [Leckbee, Joshua; Cordova, Steve; Oliver, Bryan] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Johnson, David L.] L3 Commun Pulse Sci, San Leandro, CA 94577 USA. [Toury, Martial; Rosol, Rodolphe] Commissariata Energie Pulse Sci, F-51490 Moronvilliers, France. [Bui, Bill] K Tech Corp, Albuquerque, NM 87186 USA. RP Leckbee, J (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM jjleckb@sandia.gov NR 5 TC 6 Z9 6 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 98 EP + DI 10.1109/IPMC.2008.4743588 PG 3 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400028 ER PT S AU Tully, LK Goerz, DA Speer, RD Ferriera, TJ AF Tully, L. K. Goerz, D. A. Speer, R. D. Ferriera, T. J. BE Kirkici, H TI Modular High Current Test Facility at LLNL SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB This paper describes the 1 MA, 225 kJ test facility in operation at Lawrence Livermore National Laboratory (LLNL). The capacitor bank is constructed from three parallel 1.5 mF modules. The modules are capable of switching simultaneously or sequentially via solid dielectric puncture switches. The bank nominally operates up to 10 kV and reaches peak current with all three cabled modules in approximately 30 mu s. Parallel output plates from the bank allow for cable or busbar interfacing to the load. This versatile bank is currently in use for code validation experiments, railgun related activities, switch testing, and diagnostic development. C1 [Tully, L. K.; Goerz, D. A.; Speer, R. D.; Ferriera, T. J.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Tully, LK (reprint author), Lawrence Livermore Natl Lab, 700 East Ave, Livermore, CA 94550 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 102 EP 105 DI 10.1109/IPMC.2008.4743589 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400029 ER PT S AU Barbosa, F Arnold, PA McHale, GB James, G Brown, G Cook, EG Hickman, BC AF Barbosa, F. Arnold, P. A. McHale, G. B. James, G. Brown, G. Cook, E. G. Hickman, B. C. BE Kirkici, H TI DEVELOPMENT OF SOLID-STATE DRIVERS FOR THE NIF PLASMA ELECTRODE POCKELS CELL SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB Large aperture Plasma Electrode Pockets Cells (PEPC) are an enabling technology in the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory. The Pockets cell allows the NIF laser to take advantage of multi-pass amplifier architecture, thus reducing costs and physical size of the facility. Each Pockets cell comprises four 40-cm x 40-cm apertures arranged in a 4x1 array. The combination of the Pockels cell and a thin-film polarizer, configured in a 4x1 array, form an optical switch that is key to achieving multi-pass operation. Solid-state Plasma Pulse Generators (PPGs) and high current high voltage solid-state Switch Pulse Generators (SPGs) have been developed for use in the PEPC. The solid-state plasma pulse generators initiate and maintain plasma within the cells; each pulser is capable of delivering 60J of energy to each plasma channel. Deployment of the solid-state PPGs has been completed in NIF. The MOSFET-switched SPG is capable of delivering a requisite fast rise time, 17kV flattop pulse to the cells' nonlinear crystals. A complete software and hardware control system has been developed and is currently being tested for use on the solid-state SPGs. Also a transmission line modeling, development, and testing effort is in process, in support of NIFs' Advanced Radiographic Capabilities (ARC). Work is scheduled for completion by the end of the calendar year. C1 [Barbosa, F.; Arnold, P. A.; McHale, G. B.; James, G.; Brown, G.; Cook, E. G.; Hickman, B. C.] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Barbosa, F (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94551 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 109 EP 112 DI 10.1109/IPMC.2008.4743591 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400031 ER PT S AU Nguyen, M Beukers, T Burkhart, C Larsen, R Olsen, J Tang, T AF Nguyen, M. Beukers, T. Burkhart, C. Larsen, R. Olsen, J. Tang, T. BE Kirkici, H TI DEVELOPMENT STATUS OF THE ILC MARX MODULATOR SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB The ELC Marx Modulator is under development as a lower cost alternative to the "Baseline Conceptual Design" (BCD) klystron modulator. Construction of a prototype Marx is complete and testing is underway at SLAC. The Marx employs solid state elements, IGBTs and diodes, to control the charge, discharge and isolation of the modules. The prototype is based on a stack of sixteen modules, each initially charged to similar to 11 kV, which are arranged in a Marx topology. Initially, eleven modules combine to produce the 120 kV output pulse. The remaining modules are switched in after appropriate delays to compensate for the voltage droop that results from the discharge of the energy storage capacitors. Additional elements will further regulate the output voltage to +/- 0.5%. The Marx presents several advantages over the conventional klystron modulator designs. It is physically smaller; there is no pulse transformer (quite massive at these parameters) and the energy storage capacitor bank is quite small, owing to the active droop compensation. It is oil-free; voltage hold-off is achieved using air insulation. It is air cooled; the secondary air-water heat exchanger is physically isolated from the electronic components. This paper outlines the current developmental status of the prototype Marx. It presents a detailed electrical and mechanical description of the modulator and operational test results. It will discuss electrical efficiency measurements, fault testing, and output voltage regulation. C1 [Nguyen, M.; Beukers, T.; Burkhart, C.; Larsen, R.; Olsen, J.; Tang, T.] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Nguyen, M (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. RI Tang, Tao/C-8123-2011 NR 1 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 120 EP 123 DI 10.1109/IPMC.2008.4743594 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400034 ER PT S AU Tang, T Burkhart, C AF Tang, T. Burkhart, C. BE Kirkici, H TI Hybrid MOSFET/Driver for Ultra-Fast Switching SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB The ultra-fast switching of power MOSFETs, in similar to 1ns, is very challenging. This is largely due to the parasitic inductance that is intrinsic to commercial packages used for both MOSFETs and drivers. Parasitic gate and source inductance not only limit the voltage rise time on the MOSFET internal gate structure but can also cause the gate voltage to oscillate. This paper describes a hybrid approach that substantially reduces the parasitic inductance between the driver and MOSFET gate as well as between the MOSFET source and its external connection. A flip chip assembly is used to directly attach the die-form power MOSFET and driver on a PCB. The parasitic inductances are significantly reduced by eliminating bond wires and minimizing lead length. The experimental results demonstrate ultra-fast switching of the power MOSFET with excellent control of the gate-source voltage. C1 [Tang, T.; Burkhart, C.] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Tang, T (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd,MS-49, Menlo Pk, CA 94025 USA. RI Tang, Tao/C-8123-2011 NR 4 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 128 EP 130 DI 10.1109/IPMC.2008.4743596 PG 3 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400036 ER PT S AU Woodworth, J Alexander, J Gruner, F Blickem, J Anderson, H Harden, M AF Woodworth, Joseph Alexander, Jeffrey Gruner, Fredrick Blickem, James Anderson, Harold Harden, Michel BE Kirkici, H TI LOW-INDUCTANCE GAS SWITCHES FOR LINEAR TRANSFORMER DRIVERS SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc C1 [Woodworth, Joseph; Alexander, Jeffrey] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Blickem, James] Ktech Corp Inc, Albuquerque, NM 87185 USA. [Anderson, Harold; Harden, Michel] NSTech Los Alamos, Los Alamos, NM USA. [Gruner, Fredrick] Kinetic LLC, Dales, OR USA. RP Woodworth, J (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. FU National Nuclear Security Agency [DE-AC04-94AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company for the United States Department of Energys National Nuclear Security Agency under Contract DE-AC04-94AL85000. NR 0 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 201 EP 201 DI 10.1109/IPMC.2008.4743615 PG 1 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400055 ER PT S AU Lizon, DC Gioia, JG Dale, GE Snyder, HR AF Lizon, David C. Gioia, Jack G. Dale, Gregory E. Snyder, Hans R. BE Kirkici, H TI CHARGING A BATTERY-POWERED DEVICE WITH A FIBER-OPTICALLY CONNECTED PHOTONIC POWER SYSTEM FOR ACHIEVING HIGH-VOLTAGE ISOLATION SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB We are developing a system to provide isolated power to the filament power supply of an x-ray tube located at a potential of several hundred kilovolts. In this design a fiber-optically connected Photonic Power System (PPS) is used to recharge a lithium-ion battery pack, which will subsequently supply power to the rest of the system. This paper evaluates the suitability for using the commercially available JDSU Photonic Power System for charging Li-Ion batteries. The output of the PPC converter is characterized. The technical aspects of its use for charging a variety of Li-Ion batteries are discussed. Battery charge protection requirements and safety concerns are also addressed. C1 [Lizon, David C.; Gioia, Jack G.; Dale, Gregory E.; Snyder, Hans R.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lizon, DC (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM lizon@lanl.gov RI Dale, Gregory/A-9419-2009 NR 4 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 227 EP 230 DI 10.1109/IPMC.2008.4743622 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400062 ER PT S AU Reass, WA Gribble, RF McCarthy, J AF Reass, W. A. Gribble, R. F. McCarthy, J. BE Kirkici, H TI Polyphase Resonant Converter-Modulators for the KAERI Proton Engineering Frontier Project Accelerator Klystron RF Amplifier System SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB The Korean Atomic Energy Research Institute (KAERI) is in the process of fabricating a long pulse, high average power, 100 MeV, 1.6 mA proton accelerator, called the "Proton Engineering Frontier Project" [1]. For the power conditioning and RF systems operating above 20 MeV, this system will utilize 4 modulator systems driving 7 klystrons. The klystrons are a modified version of the Thales TH2089F, a 352 MHz horizontal tube that provides 1.6 MW RF output with a 105 W, 25 A beam. The maximum expected pulse length is 1.5 ms with a 60 Hz repetition rate. The system average power, driving 2 klystrons at fall duty, is about 500 M The converter-modulator design is based on those developed by Los Alamos for the Spallation Neutron Source (SNS) accelerator at Oak Ridge National Laboratory and the Stanford (SLAC) ILC L-band RF test stand [2]. The KAERI design will benefit from the SNS and SLAC experiences as well as recent advancements [31 that reduce IGBT switching losses and other dynamic parameters by a factor of 6. These topological changes also provide for pulse width modulation (PWM) regulation of the output pulse with adaptive controls at high average power. Other fabrication and design changes will provide subtle improvements to the overall system. In addition to the expected improvement in performance and reliability, the overall electrical efficiency is expected to improve from the SNS value of similar to 93% to similar to 96% conversion efficiency. This paper will review many of the design principles and techniques for this next generation polyphase resonant converter-modulator as well as provide details of the hardware implementation. C1 [Reass, W. A.; Gribble, R. F.] Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. [McCarthy, J.] Dynapower Corp, S Burlington, VT 05403 USA. RP Reass, WA (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 231 EP + DI 10.1109/IPMC.2008.4743623 PG 2 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400063 ER PT S AU Reass, WA Roybal, WT Davis, JL Rinckel, T Durenchek, VP AF Reass, W. A. Roybal, W. T. Davis, J. L. Rinckel, T. Durenchek, V. P. BE Kirkici, H TI FAST TOTEM-POLE GRID-CATCH MOD-ANODE MODULATOR FOR THE INDIANA UNIVERSITY "LENS" KLYSTRON RF AMPLIFIER SYSTEM SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB This paper provides the electrical design and test results of the newly designed mod-anode modulators for the Indiana University Low Energy Neutron Source (LENS) klystron RF amplifier system. The design is based on totem-pole connected floating-deck vacuum tube amplifier systems, the "on-deck" turns on the klystron (via the mod-anode), the "off-deck" turns off the klystron. Via feedback techniques, the klystron mod-anode voltage tracks the klystron cathode voltage at a predetermined set-point The compensated mod-anode to cathode tracking provides for a stable klystron RF amplitude characteristic as it provides a constant klystron beam current. This constant klystron beam current is provided even as the klystron cathode voltage slumps from the (-100 kV) capacitive energy store. All klystrons operate from a common capacitor bank and power supply system. The on-deck uses a magnetron injection gun switch tube (an Injectron) as a switching and regulating element that has a pentode-like characteristic curve. The klystron mod-anode set point is determined by a voltage divider that provides a voltage reference to the on-deck modulator. The output of the on-deck connects to the klystron mod-anode. Also connected to the klystron mod-anode and on-deck is the off-deck. The off-deck uses a H.V. planar triode as a simple switch in a cascode circuit configuration, a MOSFET is in series with the tube cathode as the on-off control element. Timing signals to the on and off decks is via fiber optics. The totem-pole switching configuration provides for a significant reduction in the klystron mod-anode rise and fall time, as wen as the system overall average power dissipation. The decks need only dissipate the power necessary to charge and discharge the klystron mod-anode and deck capacitances. This provides a system of fast rise and fall, variable rep-rate, variable pulse width, with good pulse fidelity and excellent electrical efficiency. C1 [Reass, W. A.; Roybal, W. T.; Davis, J. L.] Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. [Rinckel, T.; Durenchek, V. P.] Indiana Univ, Cyclotron Facil, Bloomington, IN 47408 USA. RP Reass, WA (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 235 EP + DI 10.1109/IPMC.2008.4743624 PG 2 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400064 ER PT S AU Lehr, JM Warne, LK Jorgenson, RE Wallace, ZR Hodge, KC Caldwell, M AF Lehr, J. M. Warne, L. K. Jorgenson, R. E. Wallace, Z. R. Hodge, K. C. Caldwell, M. BE Kirkici, H TI Streamer Initiation in Volume and Surface Discharges in Atmospheric Gases SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB It is generally acknowledged that once a highly conductive channel is established between two charged and conducting materials, electrical breakdown is well established and difficult to interrupt. An understanding of the initiation mechanism for electrical breakdown is crucial for devising mitigating methods to avoid catastrophic failures. Both volumetric and surface discharges are of interest. An effort is underway where experiments and theory are being simultaneously developed. The experiment consists of an impedance matched discharge chamber capable of investigating various gases and pressures to ten atmospheres. In addition to current and voltage measurements, a high dynamic range streak camera records streamer velocities. The streamer velocities are particularly valuable for comparison with theory. A streamer model is being developed which includes photo-ionization and particle interactions with an insulating surface. The combined theoretical and experimental effort is aimed at detailed comparisons of streamer development as well as a quantitative understanding of how streamers interact with dielectric surfaces and the resulting effects on breakdown voltage. C1 [Lehr, J. M.; Warne, L. K.; Jorgenson, R. E.; Wallace, Z. R.; Hodge, K. C.; Caldwell, M.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lehr, JM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 354 EP 357 DI 10.1109/IPMC.2008.4743657 PG 4 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400097 ER PT S AU VanGordon, JA Kovaleski, SD Dale, GE AF VanGordon, J. A. Kovaleski, S. D. Dale, G. E. BE Kirkici, H TI Characterization of Power Insulated-Gate Bipolar Transistors to Create a SPICE Model for Pulsed Power Applications SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB Power insulated gate bipolar transistors (IGBTs) are frequently used in pulsed power applications. While published data is readily available for most IGBTs under steady-state conditions, little information is known for a given IGBT regarding pulsed power conditions. This paper presents a characterization process of power IGBTs for creating IGBT SPICE models. Each IGBT will be subjected to single 5 mu s pulses at 4.5 kV and I kA. During the pulse, characteristics such as rise time, fall time, maximum collector current, and maximum collector-emitter voltage will be measured. Additionally, the effects of the gate drive with respect to the collector-emitter characteristics will be observed. This process will be demonstrated with the IXYS IXEL40N400 and the Powerex QIS4506001 IGBTs to allow for circuit simulations with these models as circuit elements. C1 [VanGordon, J. A.; Kovaleski, S. D.] Univ Missouri, Columbia, MO 65211 USA. [Dale, G. E.] Los Alamos Natl Lab, High Power Electrodynam Grp, Los Alamos, NM 87544 USA. RP VanGordon, JA (reprint author), Univ Missouri, Columbia, MO 65211 USA. RI Dale, Gregory/A-9419-2009; OI Kovaleski, Scott/0000-0002-5831-6388 FU Los Alamos National Laboratory FX This work was supported by Los Alamos National Laboratory. NR 10 TC 3 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 362 EP + DI 10.1109/IPMC.2008.4743659 PG 2 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400099 ER PT S AU Jiang, C Sozer, EB Umstattd, RJ Chen, H Hsu, H Gundersen, MA AF Jiang, C. Sozer, E. B. Umstattd, R. J. Chen, H. Hsu, H. Gundersen, M. A. BE Kirkici, H TI Photocathodes for Compact Optical Triggering of Back-Lighted Thyratrons SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc ID SWITCHES AB Light-activated pseudospark switches, also called back-lighted thyratrons (BLTs), are low pressure (typ. <= 0.5 Torr), high voltage (typ. 10-50 W), high current (1-> 100 kA) glow-mode switches [1,2,3]. It is of interest to develop ultra-compact BLTs [4] with reliable and practical optical triggering systems for applications of compact pulsed power. The present work investigates the utility of photocathode materials inside mini-BLTs to enhance the switch performance, improve the trigger characteristics (delay, jitter and reliability), and provide optimal conditions for compact optical triggering, including the use of light emitting diodes. Photocathode material properties, including low work function, high quantum yield under the mini-BLT operation pressure (0.1-1 Torr), and sufficiently robust to maintain a reasonable lifetime, are critical in material selection. We present results of investigations of a variety of cathode materials as potential candidates for BLT cathodes. Photoelectron yields of candidate cathode materials are measured in a test bed under relevant vacuum conditions with and without applying positive bias at the collector. C1 [Jiang, C.; Sozer, E. B.; Chen, H.; Hsu, H.; Gundersen, M. A.] Univ Southern Calif, Dept EE Electrophys, Los Angeles, CA 90089 USA. [Umstattd, R. J.] Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Jiang, C (reprint author), Univ Southern Calif, Dept EE Electrophys, Los Angeles, CA 90089 USA. EM chunqi@usc.edu FU Air Force Office of Scientific Research FX This work is supported by the Air Force Office of Scientific Research. NR 6 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 477 EP + DI 10.1109/IPMC.2008.4743694 PG 2 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400134 ER PT S AU Beveridge, JR MacGregor, SJ Timoshkin, IV Lehr, JM AF Beveridge, J. R. MacGregor, S. J. Timoshkin, I. V. Lehr, J. M. BE Kirkici, H TI A Corona-Stabilised Plasma Closing Switch SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB Corona-stabilised plasma closing switches, filled with electronegative gases such as SF6 and air, have been used in pulsed-power applications as repetitive switching devices for the last 10 years. Their high repetition-rate capabilities coupled with their relatively simple design and construction have made them suitable alternatives to thyratrons and semi-conductor switches. As well as having repetitive switching capabilities, corona-stabilised plasma closing switches have the potential to work at elevated voltages through the incorporation of multiple electrode sets. This allows high-voltage operation with inherent voltage grading between the electrodes. A further feature of the switches is that they have relatively low jitter under triggered condition. This paper reports on some of the operational features of a new design of corona-stabilised, cascade switch that utilises air at atmospheric pressure as the insulating gas. C1 [Beveridge, J. R.; MacGregor, S. J.; Timoshkin, I. V.] Univ Strathclyde, Inst Energy & Environm, Royal Coll Bldg,204 George St, Glasgow G1 1XW, Lanark, Scotland. [Lehr, J. M.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RP Beveridge, JR (reprint author), Univ Strathclyde, Inst Energy & Environm, Royal Coll Bldg,204 George St, Glasgow G1 1XW, Lanark, Scotland. NR 8 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 487 EP + DI 10.1109/IPMC.2008.4743697 PG 2 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400137 ER PT S AU Timoshkin, IV MacGregor, SJ Given, MJ Beveridge, JR Lehr, JM AF Timoshkin, I. V. MacGregor, S. J. Given, M. J. Beveridge, J. R. Lehr, J. M. BE Kirkici, H TI Dynamic Characteristics Of Corona Discharges In Point-Plane Electrode Topologies Influenced By Space Charge SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc AB The paper presents an analytical analysis of the steady state current-voltage characteristics of corona discharges in point-plane electrode configurations. The paper also discusses the dynamic impulse characteristics of corona discharges based on the solution of the Poisson and the continuity equations which includes the displacement current due to time-varying electric field. The hyperboloid approximation is used to describe the IV characteristics of corona discharges. The best fit of analytically calculated IV curves to experimental data provides the value of the mobility for the charge carriers in the corona discharge. The results of this work provides a greater understanding of the behaviour of corona and will assist with the operational analysis of impulsive pre-breakdown processes in point-plane electrode topologies in electron-negative gases These topologies are important as they are employed in corona stabilised plasma closing switches. C1 [Timoshkin, I. V.; MacGregor, S. J.; Given, M. J.; Beveridge, J. R.] Univ Strathclyde, Inst Energy & Environm, 204 George St, Glasgow G1 1XW, Lanark, Scotland. [Lehr, J. M.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RP Timoshkin, IV (reprint author), Univ Strathclyde, Inst Energy & Environm, 204 George St, Glasgow G1 1XW, Lanark, Scotland. NR 6 TC 1 Z9 1 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 495 EP + DI 10.1109/IPMC.2008.4743699 PG 2 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400139 ER PT S AU LeChien, K Savage, M Stygar, W Wakeland, P Anaya, V Lott, J AF LeChien, Keith Savage, Mark Stygar, William Wakeland, Peter Anaya, Victor Lott, John BE Kirkici, H TI A 6.25 MV LASER TRIGGERED GAS SWITCH FOR THE REFURBISHED Z ACCELERATOR SO PROCEEDINGS OF THE 2008 IEEE INTERNATIONAL POWER MODULATORS AND HIGH VOLTAGE CONFERENCE SE IEEE International Power Modulator and High Voltage Conference LA English DT Proceedings Paper CT 28th International Power Modulator Symposium/2008 High Voltage Workshop CY MAY 27-31, 2008 CL Las Vegas, NV SP IEEE Dielect & Elect Insulat Soc, IEEE Nucl & Plasma Sci Soc, IEEE Electron Devices Soc C1 [LeChien, Keith; Savage, Mark; Stygar, William] Sandia Natl Labs, Adv Accelerator Phys, POB 5800, Albuquerque, NM 87185 USA. [Wakeland, Peter; Anaya, Victor; Lott, John] Ktech Corp Inc, Albuquerque, NM USA. RP LeChien, K (reprint author), Sandia Natl Labs, Adv Accelerator Phys, POB 5800, Albuquerque, NM 87185 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2380-808X BN 978-1-4244-1534-2 J9 IEEE INT POWER MODUL PY 2008 BP 567 EP 567 DI 10.1109/IPMC.2008.4743721 PG 1 WC Engineering, Electrical & Electronic; Physics, Fluids & Plasmas SC Engineering; Physics GA BJC84 UT WOS:000264853400161 ER PT B AU Hereld, M Papka, ME Uram, TD AF Hereld, Mark Papka, Michael E. Uram, Thomas D. BE Smari, WW McQuay, W TI Collaboration as a second thought SO PROCEEDINGS OF THE 2008 INTERNATIONAL SYMPOSIUM ON COLLABORATIVE TECHNOLOGIES AND SYSTEMS: CTS 2008 SE International Symposium on Collaborative Technologies and Systems-CTS LA English DT Proceedings Paper CT International Symposium on Collaborative Technologies and Systems CY MAY 19-23, 2008 CL Irvine, CA SP IEEE, Ball Aerosp & Technol Corp, Sci Appl Int Corp DE collaboration; visualization; best-practices; human-computer interaction AB Collaboration is often an afterthought to a project or development. In this paper we describe and analyze our experiences in developing collaborative technologies, most often involving the sharing of visual information. We have often developed these in a context that required us to retrofit existing analysis applications with collaboration capabilities. This approach, though fruitful, is time-consuming, expensive, and often difficult to re-apply elsewhere - it is just hard to change an existing application. One way to make such an effort easier is to package the collaborative components as a kit that can be leveraged on a case-by-case basis. The fixed interface provided by a well-designed toolkit eases the integration process by providing an unchanging and familiar set of components to deploy. Better still, we find, are approaches that require no modification of applications while providing rich and powerful means for sharing information with collaborators. We discuss three separate and illuminating examples that meet this criterion in different ways: (1) building the collaborative potential into the underlying abstractions on which operating systems are built, (2) building tools that live side-by-side with any application in the context provided by the operating system, or by (3) building information tools that use collaborative modalities to better integrate with our workflow. These are probably not the only options, but they all derive from an approach where collaboration is considered early in the design process and therefore manifests itself deep in the computing infrastructure giving it a wider cast. C1 [Hereld, Mark; Papka, Michael E.; Uram, Thomas D.] Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. RP Hereld, M (reprint author), Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. EM hereld@mcs.anl.gov; papka@mcs.anl.gov; turam@mcs.anl.gov OI Hereld, Mark/0000-0002-0268-2880 NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 978-1-4244-2248-7 J9 INT S COLLAB TECHNOL PY 2008 BP 196 EP 202 DI 10.1109/CTS.2008.4543932 PG 7 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BHW23 UT WOS:000256994300028 ER PT B AU Kendall, W Glatter, M Huang, J Hoffman, F Bernholdt, DE AF Kendall, Wesley Glatter, Markus Huang, Jian Hoffman, Forrest Bernholdt, David E. BE Smari, WW McQuay, W TI Web enabled collaborative climate visualization in the Earth System Grid SO PROCEEDINGS OF THE 2008 INTERNATIONAL SYMPOSIUM ON COLLABORATIVE TECHNOLOGIES AND SYSTEMS: CTS 2008 SE International Symposium on Collaborative Technologies and Systems-CTS LA English DT Proceedings Paper CT International Symposium on Collaborative Technologies and Systems CY MAY 19-23, 2008 CL Irvine, CA SP IEEE, Ball Aerosp & Technol Corp, Sci Appl Int Corp DE large data visualization; climate modeling; distributed collaborative visualization ID SCALE AB The recent advances in high performance computing, storage and networking technologies have enabled fundamental changes in current climate research. While sharing datasets and results is already common practice in climate modeling, direct sharing of the analysis and visualization process is also becoming feasible. We report our efforts to develop a capability, coupled with the Earth System Grid (ESG), for sharing an entire executable workspace of visualization among collaborators. Evolutionary history of visualizations of research findings can also be captured and shared The data intensive nature of the visualization system requires using several advanced techniques of visualization and parallel computing. With visualization clients implemented through standard web browsers, however, the ensuing complexity is made transparent to end-users. We demonstrate the efficacy of our system using cutting edge climate datasets. C1 [Kendall, Wesley; Glatter, Markus; Huang, Jian] Univ Tennessee, Knoxville, TN 37996 USA. [Hoffman, Forrest; Bernholdt, David E.] Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37830 USA. RP Kendall, W (reprint author), Univ Tennessee, Knoxville, TN 37996 USA. EM kendall@cs.utk.edu; glatter@cs.utk.edu; huangj@cs.utk.edu; hoffmanfm@ornl.gov; bernholdtde@ornl.gov RI Hoffman, Forrest/B-8667-2012 OI Hoffman, Forrest/0000-0001-5802-4134 FU Institute of Ultra-Scale Visualization (www.ultravis.org), under the auspices of the DOE Scientific Discovery through Advanced Computing (SciDAC) program; NSF [CNS-0437508]; DOE Early Career PI [DOE DE-FG02-04ER25610]; Climate Change Research Division (CCRD) of the Office of Biological and Environmental Research (OBER); Computational Science Research and Partnerships (SciDAC); Office of Advanced Scientific Computing Research (OASCR) within the U.S. Department of Energy's Office of Science (SC); UT-Battelle, LLC, for the U.S. Department of Energy [DE-AC05-00OR22725] FX The authors gratefully acknowledge the primary source of funding for this work is provided through Institute of Ultra-Scale Visualization (www.ultravis.org), under the auspices of the DOE Scientific Discovery through Advanced Computing (SciDAC) program. This work is also supported in part by NSF grant CNS-0437508 and a DOE Early Career PI grant awarded to Jian Huang (grant no. DOE DE-FG02-04ER25610). We are in debt for our crucial collaboration with the Logistical Computing Laboratory (LoCI) co-directed by Dr. Micah Beck and Dr. Terry Moore at the University of Tennessee. LoCI lab researcher, Huadong Liu, is the primary designer of the heterogeneous scheduler [7] used in our system. We would also like to thank Dr. David Erickson a nd Dr. John Drake (ORNL) for the many in-depth discussions that helped us to conceive our system, and Jamison Daniel (ORNL) for his expertise on climate datasets. The Earth System Grid (ESG) and the Carbon-Land Model Intercomparison Project (C-LAMP) are partially sponsored by the Climate Change Research Division (CCRD) of the Office of Biological and Environmental Research (OBER) and the Computational Science Research and Partnerships (SciDAC) Division of the Office of Advanced Scientific Computing Research (OASCR) within the U.S. Department of Energy's Office of Science (SC). This research used resources of the National Center for Computational Science (NCCS) at Oak Ridge National Laboratory (ORNL), which is managed by UT-Battelle, LLC, for the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. NR 14 TC 0 Z9 0 U1 0 U2 10 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 978-1-4244-2248-7 J9 INT S COLLAB TECHNOL PY 2008 BP 212 EP 220 DI 10.1109/CTS.2008.4543934 PG 9 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BHW23 UT WOS:000256994300030 ER PT B AU Altunay, M Byrd, GT Brown, DE Dean, RA AF Altunay, Mine Byrd, Gregory T. Brown, Doug E. Dean, Ralph A. BE Smari, WW McQuay, W TI An interaction-based access control model (IBAC) for collaborative services SO PROCEEDINGS OF THE 2008 INTERNATIONAL SYMPOSIUM ON COLLABORATIVE TECHNOLOGIES AND SYSTEMS: CTS 2008 SE International Symposium on Collaborative Technologies and Systems-CTS LA English DT Proceedings Paper CT International Symposium on Collaborative Technologies and Systems CY MAY 19-23, 2008 CL Irvine, CA SP IEEE, Ball Aerosp & Technol Corp, Sci Appl Int Corp DE access control; collaboration context; web services; workflow planning AB A collaboration is a collection of services that work together to achieve a common goal. Although collaborations help when tackling difficult problems, they lead to security issues. First, a collaboration is often performed by services that are drawn from different security domains. Second, a service interacts with multiple peer services during the collaboration. These interactions are not isolated from one another -- e.g., data may flow through a sequence of different services. As a result, a service is exposed to multiple peer services in varying degrees, leading to different security threats. We identify the types of interactions that can be present in collaborations, and discuss the security threats due to each type. We propose a model for representing the collaboration context so that a service can be made aware of the existing interactions. We provide an access control model for a service participating in a collaboration. We couple our access control model with a policy model, so that the access requirements from collaborations can be expressed and evaluated. C1 [Altunay, Mine] Fermi Natl Lab, Batavia, IL 60510 USA. [Byrd, Gregory T.; Brown, Doug E.; Dean, Ralph A.] North Carolina State Univ, Raleigh, NC 27695 USA. RP Altunay, M (reprint author), Fermi Natl Lab, Batavia, IL 60510 USA. EM maltunay@fnal.gov; gbyrd@ncsu.edu; debrown@ncsu.edu; ralph_dean@ncsu.edu NR 18 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 978-1-4244-2248-7 J9 INT S COLLAB TECHNOL PY 2008 BP 547 EP 554 DI 10.1109/CTS.2008.4543977 PG 8 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BHW23 UT WOS:000256994300073 ER PT B AU Jagode, H Hein, J AF Jagode, Heike Hein, Joachim GP IEEE Computer Soc TI Custom assignment of MPI ranks for parallel multi-dimensional FFTs: Evaluation of BG/P versus BG/L SO PROCEEDINGS OF THE 2008 INTERNATIONAL SYMPOSIUM ON PARALLEL AND DISTRIBUTED PROCESSING WITH APPLICATIONS LA English DT Proceedings Paper CT IEEE International Symposium on Parallel and Distributed Processing with Applications CY DEC 10-12, 2008 CL Sydney, AUSTRALIA SP IEEE, IEEE Comp Soc, IEEE TCSC AB For many scientific applications, the Fast Fourier Transformation (FFT) of multi-dimensional data is the kernel that limits scalability on a large number of processors. This paper investigates the extent of performance improvements for a parallel three-dimensional FFT (3D-FFT) implementation when using customized MPI task mappings. The MPI tasks are mapped in a customized fashion from the two-dimensional virtual processor grid of the algorithm to the physical hardware of a system with a mesh interconnect. We compare and analyze the outcomes on Blue Gene/P with those from previous investigations on Blue Gene/L. The performance analysis is based on bandwidth considerations. The results demonstrate that on Blue Gene/P a carefully chosen MPI task mapping with regards to the network characteristics is more important compared to Blue Gene/L and yields significant improvement. C1 [Jagode, Heike] Univ Tennessee, Oak Ridge Natl Lab, Knoxville, TN 37996 USA. [Hein, Joachim] Univ Edinburgh, EPCC, Edinburgh EH8 9YL, Midlothian, Scotland. RP Jagode, H (reprint author), Univ Tennessee, Oak Ridge Natl Lab, Knoxville, TN 37996 USA. EM jagode@eecs.utk.edu; joachim@epcc.ed.ac.uk NR 11 TC 4 Z9 4 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3471-8 PY 2008 BP 271 EP + DI 10.1109/ISPA.2008.136 PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BIW68 UT WOS:000263416900030 ER PT B AU Soukoulis, CM AF Soukoulis, Costas M. BE Cui, TJ Smith, DR TI Bending Back Light: The Science of Negative Index Materials SO PROCEEDINGS OF THE 2008 INTERNATIONAL WORKSHOP ON METAMATERIALS LA English DT Proceedings Paper CT International Workshop on Metamaterials CY NOV 09-12, 2008 CL Nanjing, PEOPLES R CHINA SP IEEE AP-MTT-EMC Nanjing Joint Chapter, Natl Nat Sci Fdn China, Minist Educ, SE Univ, State Key Lab Millimeter Waves ID METAMATERIAL; WAVELENGTHS C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Soukoulis, CM (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. EM soukoulis@ameslab.gov NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 978-1-4244-2608-9 PY 2008 BP 4 EP 5 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BIT81 UT WOS:000262656300003 ER PT B AU Bir, G Jonkman, J AF Bir, Gunjit Jonkman, Jason GP ASME TI MODAL DYNAMICS OF LARGE WIND TURBINES WITH DIFFERENT SUPPORT STRUCTURES SO PROCEEDINGS OF THE 27TH INTERNATIONAL CONFERENCE ON OFFSHORE MECHANICS AND ARCTIC ENGINEERING - 2008, VOL 6 LA English DT Proceedings Paper CT 27th International Conference on Offshore Mechanics and Arctic Engineering CY JUN 15-20, 2008 CL Estoril, PORTUGAL SP ASME, Ocean, Offshore, & Arct Engn Div AB This paper presents modal dynamics of floating-platform-supported and monopile-supported offshore turbines, which are gaining attention for their ability to capture the immense wind resources available over coastal waters. Minimal dynamic loads and the absence of instability are imperative to the success of these turbines. Modal dynamics determine both loads and instabilities to a large extent, and therefore must always be analyzed. Also, to model the turbine, several aeroelastic computer codes require modes of the major components, e.g., the rotor blades and the rotor-nacelle support structure. To compute such modes, we used a recently developed finite-element code called BModes. The code provides coupled modes either for the rotating blades or for the support structure. A coupled mode implies presence of coupled flexural, axial, and torsion motions in a natural mode of vibration. In this paper, we use BModes to provide modes only for flexible towers, which carry head mass (rotor-nacelle subassembly modeled as a rigid body) and are mounted atop either a floating platform or a soil-supported monopile. The code accounts for the effects of hydrodynamic inertia, hydrostatic restoring, and mooring lines stiffness on the floating platform. It also accounts for the distributed hydrodynamic mass on the submerged part of the tower and for the elastic foundation surrounding the monopile. Results are obtained for three turbine configurations: land-based turbine, floating-platform-supported turbine, and monopile-supported turbine. Three foundation models are used for the monopile configuration. Results show that the hydrodynamic and elastic-foundation effects strongly influence the turbine modal dynamics. C1 [Bir, Gunjit; Jonkman, Jason] Natl Renewable Energy Lab, Golden, CO USA. RP Bir, G (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO USA. NR 17 TC 0 Z9 1 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4823-4 PY 2008 BP 669 EP 679 PG 11 WC Energy & Fuels; Engineering, Marine; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIX43 UT WOS:000263581700073 ER PT B AU Gerdes, K Gernmen, R AF Gerdes, Kirk Gernmen, Randy GP ASME TI POROUS ANODE MODEL FOR COAL SYNGAS FUELLED SOFC: COMBINED MASS AND ENERGY TRANSPORT NORMAL TO CELL PLANE SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering,and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine ID RADIATION HEAT-TRANSFER; PERFORMANCE; SIMULATION; OPERATION; GAS; US AB Solid oxide fuel cells are being developed for integrated gasification combined cycle hybrid power systems. It is therefore necessary to evaluate the coupled temperature and concentration profiles for SOFC anodes exposed to coal syngas. In this work the SOFC anode was treated as a porous composite of 50/50 (volume) Ni/YSZ. Porous transport was modeled using the dusty gas model (DGM) and included two pore reactions, namely water gas shift and steam reforming of methane. The thermal transport model considered heat exchange by radiation between the interconnect and SOFC surface, convective transfer from bulk gas flow over the anode, heat generation terms due to pore reactions, and heat generation terms at the electrolyte boundary due to electrochemical reactions, ohmic heating, and concentration polarization. Composition profiles throughout the porous anode were considered for the DGM alone and were compared to the DGM including energy (DGME). The cases examined were for current densities ranging from 0.000-0.750 A/cm(2) and for pressures from 1-19 atm absolute. Simulation results predict that the average cell operating temperature will increase 10 to 60 degrees C relative to the furnace wall with inclusion of the energy equations. However, the thermal gradients within the anode are small due to the good thermal conductivity of the Ni-based anode. The effect of inclusion of energy transport on the hydrogen concentration profile is mixed depending on the independent parameter considered, with relative insensitivity to changes in the current density, but modest sensitivity to changes in operating pressure. Consideration of the thermal transport is important for determination of the interaction of coal syngas trace species with the anode, but is less critical for material stability. C1 [Gerdes, Kirk; Gernmen, Randy] US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP Gerdes, K (reprint author), US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. NR 27 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 165 EP 175 PG 11 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700023 ER PT B AU VanOsdol, JG Gemmen, R Liese, E AF VanOsdol, John G. Gemmen, Randall Liese, Eric GP ASME TI EXAMINATION OF THE EFFECT OF SYSTEM PRESSURE RATIO AND HEAT RECUPERATION ON THE EFFICIENCY OF A COAL BASED GAS TURBINE FUEL CELL HYBRID POWER GENERATION SYSTEM WITH CO2 CAPTURE SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine AB This paper examines two coal-based hybrid configurations that employ separated anode and cathode streams for the capture and compression Of CO2. One configuration uses a standard Brayton cycle, and the other adds heat recuperation ahead of the fuel cell. Results show that peak efficiencies near 55% are possible, regardless of cycle configuration, including the cost in terms of energy production Of CO2 capture and compression. The power that is required to capture and compress the CO2 is shown to be approximately 15% of the total plant power. C1 [VanOsdol, John G.; Gemmen, Randall; Liese, Eric] Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP VanOsdol, JG (reprint author), Natl Energy Technol Lab, 3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 407 EP 415 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700050 ER PT B AU Colella, WA Schneider, SH Kammen, DM Jhunjhunwala, A Teo, N AF Colella, Whitney A. Schneider, Stephen H. Kammen, Daniel M. Jhunjhunwala, Aditya Teo, Nigel GP ASME TI PART I OF II: DEVELOPMENT OF MERESS MODEL - DEVELOPING SYSTEM MODELS OF STATIONARY COMBINED HEAT AND POWER (CHP) FUEL CELL SYSTEMS (FCSs) FOR REDUCED COSTS AND GREENHOUSE GAS (GHG) EMISSIONS SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering,and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine DE Maximizing Emission Reductions and Economic Savings Simulator (MERESS) optimization tool; fuel cell system (FCS); greenhouse gas emissions (GHG); carbon dioxide (CO2) emissions; networks; cogeneration; combined heat and power (CHP); cost; profitability; thermal distribution networks; low-voltage electricity distribution networks; optimization; heat recovery; distributed energy systems; operating strategy; stand alone (SA); networked (NW); heat load following (HLF); electricity load following (ELF); no load following (NLF); variable heat-to-power ratio (VHP); fixed heat-to-power ratio (FHP) ID SUBSYSTEM AB Stationary combined heat and power (CHP) fuel cell systems (FCSs) can provide electricity and heat for buildings, and can reduce greenhouse gas (GHG) emissions significantly if they are configured with an appropriate installation and operating strategy. The Maximizing Emission Reductions and Economic Savings Simulator (MERESS) is an optimization tool that was developed to allow users to evaluate avant-garde strategies for installing and operating CHP FCSs in buildings. These strategies include networking, load following, and the use of variable heat-to-power ratios, all of which commercial industry has typically overlooked. A primary goal of the MERESS model is to use relatively inexpensive simulation studies to identify more financially and environmentally effective ways to design and install FCSs. It incorporates the pivotal choices that FCS manufacturers, building owners, emission regulators, competing generators, and policy makers make, and empowers them to evaluate the effect of their choices directly. MERESS directly evaluates trade-offs among three key goals: GHG reductions, energy cost savings for building owners, and high sales revenue for FCS manufacturers. MERESS allows users to evaluate these design trade-offs and to identify the optimal control strategies and building load curves for installation based on either 1) maximum GHG emission reductions or 2) maximum cost savings to building owners. Part I of 11 articles discusses the motivation and key assumptions behind MERESS model development. Part 11 of 11 articles discusses run results from MERESS for a California town and makes recommendations for further FCS installments (Colella 2008 (a)). C1 [Colella, Whitney A.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Colella, WA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 54 TC 0 Z9 0 U1 1 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 541 EP 562 PG 22 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700065 ER PT B AU Colella, WG Schneider, SH Kammen, DM Jhunjhunwala, A Teo, N AF Colella, Whitney G. Schneider, Stephen H. Kammen, Daniel M. Jhunjhunwala, Aditya Teo, Nigel GP ASME TI PART II OF II: DEPLOYMENT OF MERESS MODEL - DESIGNING, CONTROLLING, AND INSTALLING STATIONARY COMBINED HEAT AND POWER (CHP) FUEL CELL SYSTEMS (FCSs) TO REDUCE COSTS AND GREENHOUSE GAS (GHG) EMISSIONS SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering,and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine DE Maximizing Emission Reductions and Economic Savings Simulator (MERESS) optimization tool; fuel cell ID BIOGAS AB The Maximizing Emission Reductions and Economic Savings Simulator (MERESS) is an optimization tool that allows users to evaluate avant-garde strategies for installing and operating combined heat and power (CHP) fuel cell systems (FCSs) in buildings. This article discusses the deployment of MERESS to show illustrative results for a California campus town, and, based on these results, makes recommendations for further installations of FCSs to reduce greenhouse gas (GHG) emissions. MERESS is used to evaluate one of the most challenging FCS types to use for GHG reductions, the Phosphoric Acid Fuel Cell (PAFC) system. These PAFC FCSs are tested against a base case of a CHIP combined cycle gas turbine (CCGT). Model results show that three competing goals (GFIG emission reductions, cost savings to building owners, and FCS manufacturer sales revenue) are best achieved with different strategies, but that all three goals can be met reasonably with a single approach. According to MERESS, relative to a base case of only a CHP CCGT providing heat and electricity with no FCSs, the town achieves the highest 1) GHG emission reductions, 2) cost savings to building owners, and 3) FCS manufacturer sales revenue each with three different operating strategies, under a scenario of full incentives and a $100/tonne carbon dioxide (CO(2)) tax (Scenario D). The town achieves its maximum CO(2) emission reduction, 37% relative to the base case, with operating Strategy V: stand alone operation (SA), no load following (NLF), and a fixed heat-to-power ratio (FHP) [SA, NLF, FHP] (Scenario E). The town's building owners gain the highest cost savings, 25%, with Strategy I: electrically and thermally networked (NW), electricity power load following (ELF), and a variable heat-to-power ratio (VHP) [NW, ELF, VHP] (Scenario D). FCS manufacturers generally have the highest sales revenue with Strategy III: NW, NLF, with a fixed heat-to-power ratio (FHP) [NW, NLF, FHP] (Scenarios B, C, and D). Strategies III and V are partly consistent with the way that FCS manufacturers design their systems today, primarily as NLF with a FHP. By contrast, Strategy I is avant-garde for the fuel cell industry, in particular, in its use of a VHP and thermal networking. Model results further demonstrate that FCS installations can be economical for building owners without any carbon tax or government incentives. Without any carbon tax or state and federal incentives (Scenario A), Strategy I is marginally economical, with 3% energy cost savings, but with a 29% reduction in CO(2) emissions. Strategy I is the most economical strategy for building owners in all scenarios (Scenarios A, B, C, and D) and, at the same time, reasonably achieves other goals of large GFIG emission reductions and high FCS manufacturer sales revenue. Although no particular building type stands out as consistently achieving the highest emission reductions and cost savings (Scenarios B-2 and E-2), certain building load curves are clear winners. For example, buildings with load curves similar to Stanford's Mudd Chemistry building (a wet laboratory) achieve maximal cost savings (1.5% with full federal and state incentives but no carbon tax) and maximal CO(2) emission reductions (32%) (Scenarios B-2 and E-2). Finally, based on these results, this work makes recommendations for reducing GHG further through FCS deployment. (Part I of II articles discusses the motivation and key assumptions behind the MERESS model development (Colella 2008).) C1 [Colella, Whitney G.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Colella, WG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 563 EP 589 PG 27 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700066 ER PT B AU Kurtz, J Wipke, K Sprik, S AF Kurtz, Jennifer Wipke, Keith Sprik, Sam GP ASME TI FUEL CELL VEHICLE LEARNING DEMONSTRATION: STUDY OF FACTORS AFFECTING FUEL CELL DEGRADATION SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering,and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine AB The 5 year "Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project" (or Fuel Cell Vehicle Learning Demonstration) was initiated by the U.S. Department of Energy (DOE) in 2004. The purpose of the project is to conduct an integrated field validation that simultaneously examines the performance of fuel cell vehicles and the supporting hydrogen infrastructure. Four industry teams are currently operating more than 92 vehicles and 14 refueling stations throughout the United States. More than 40 additional vehicles and several additional refueling stations will be added to the project through 2009. At the National Renewable Energy Laboratory (NREL), on-road driving and refueling data are analyzed to assess the technology status and progress, as well as to provide feedback to the hydrogen research and development community. A new/updated set of public results, in the form of composite data products (constructed to protect the intellectual property of the four teams), is released twice a year in the spring and fall. In addition to the public results, detailed analyses results are shared with each participating team. One of the analyses studies fuel cell degradation. The study includes following the fuel cell performance degradation trends, e.g. identifying fuel cell stacks that are decaying at a different rate than others of a similar design and in the same fleet, and explores connections between the real world data and fuel cell degradation. This study differs from other degradation studies in a lab setting or at the single cell level because this study uses full scale fuel cell stacks in vehicles with on-road driving and refueling. In the study, researchers investigate degradation factors by applying multivariate analyses for each individual team and for the combination of all four teams. Detailed results are reviewed with the individual teams in an effort to improve each analysis iteration and comprehension of the results. This paper will detail NREL's study of fuel cell degradation factors by describing the process, reviewing the latest public results, and reporting on any observed dominant factor groups affecting fuel cell degradation. C1 [Kurtz, Jennifer; Wipke, Keith; Sprik, Sam] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kurtz, J (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM Jenniferkurtz@nrel.gov NR 4 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 591 EP 602 PG 12 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700067 ER PT B AU Tsai, A Banta, L Tucker, D Gemmen, R AF Tsai, Alex Banta, Larry Tucker, David Gemmen, Randall GP ASME TI RGA ANALYSIS OF A SOLID OXIDE FUEL CELL GAS TURBINE HYBRID PLANT SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering,and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine AB This paper presents a Relative Gain Array (RGA) analysis of a simulated SOFC/Gas Turbine plant based on a multivariate empirical formulation of a 300kW hybrid system. The HyPer test facility at the National Energy Technology Laboratory, served as the test bed for deriving frequency response data and subsequent multivariable model of a direct fired, recuperated hybrid cycle plant. Through the modulation of various airflow bypass-valves, magnitude and phase data is used to formulate Transfer Function (TF) equations that describe input/output system interaction. A frequency dependent RGA calculation of the empirical Transfer Function matrix provides a means of quantifying the degree of coupling between system inputs and outputs for the configuration studied. Various input/output interaction time scales are obtained to identify frequencies where fully developed system coupling occur. Analysis of the RGA matrix leads to a better understanding of the inherent properties the hybrid configuration, and can serve as a validating tool to existing analytical RGA calculations of similar types of hybrids. C1 [Tsai, Alex; Banta, Larry; Tucker, David; Gemmen, Randall] W Virginia Univ, Natl Energy Technol Lab, Morgantown, WV 26506 USA. RP Tsai, A (reprint author), W Virginia Univ, Natl Energy Technol Lab, Morgantown, WV 26506 USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 675 EP 680 PG 6 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700077 ER PT B AU Tsai, A Banta, L Tucker, D Gemmen, R AF Tsai, Alex Banta, Larry Tucker, David Gemmen, Randall GP ASME TI Multivariable Robust Control of a Simulated Hybrid Solid Oxide Fuel Cell Gas Turbine Plant SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering,and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine AB This paper presents a systematic approach to the multivariable robust control of a hybrid fuel cell gas turbine plant. The hybrid configuration under investigation comprises a physical simulation of a 300kW fuel cell coupled to a 120kW auxiliary power unit single spool gas turbine. The facility provides for the testing and simulation of different fuel cell models that in turn help identify the key issues encountered in the transient operation of such systems. An empirical model of the facility consisting of a simulated fuel cell cathode volume and balance of plant components is derived via frequency response data. Through the modulation of various airflow bypass valves within the hybrid configuration, Bode plots are used to derive key input/output interactions in Transfer Function format. A multivariate system is then built from individual transfer functions, creating a matrix that serves as the nominal plant in an H-Infinity robust control algorithm. The controller's main objective is to track and maintain hybrid operational constraints in the fuel cell's cathode airflow, and the turbo machinery states of temperature and speed, under transient disturbances. This algorithm is then tested on a Simulink/MatLab platform for various perturbations of load and fuel cell heat effluence. C1 [Tsai, Alex; Banta, Larry; Tucker, David; Gemmen, Randall] W Virginia Univ, Natl Energy Technol Lab, Morgantown, WV 26506 USA. RP Tsai, A (reprint author), W Virginia Univ, Natl Energy Technol Lab, Morgantown, WV 26506 USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 681 EP 689 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700078 ER PT B AU Chen, KS AF Chen, Ken S. GP ASME TI MODELING WATER-DROPLET DETACHMENT FROM GDL/CHANNEL INTERFACE IN PEM FUEL CELLS SO PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON FUEL CELL SCIENCE, ENGINEERING, AND TECHNOLOGY - 2008 LA English DT Proceedings Paper CT 6th International Conference on Fuel Cell Science, Engineering,and Technology CY JUN 16-18, 2008 CL Denver, CO SP ASME Nanotechnol Inst, Univ Calif, Irvine ID FLOW CHANNEL; VISUALIZATION; INSTABILITY; BEHAVIOR; DYNAMICS AB The onset of water-droplet detachment from the cathode GDL (gas diffusion layer)/channel interface in PEM (proton exchange membrane or polymer electrolyte membrane) fuel cells was studied numerically and analytically in the inertia-dominating flow regime. This is the flow regime of interest in real-world PEM fuel-cell applications. Our three-dimensional (3-D) numerical model employs the VOF (volume of fluid) method to track the dynamic liquid/gas interface as water droplet is being deformed and eventually detached by flowing-air drag. Our simplified, analytical model is based on the force balance between pressure drag tending to detach the droplet and surface tension tending to hold the droplet in place. Using our numerical model and for a given initial droplet size, we compute the 3-D droplet shape as a function of air-flow velocity - this enables us to determine the critical velocity above which the droplet is detached. Analytically, we develop an explicit expression that relates the critical air-flow velocity to droplet diameter, channel height, and static contact angle. We compare computed critical velocities at various droplet diameters with experimental data available from the literature and reasonably good agreements are obtained. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chen, KS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 2 Z9 2 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4318-5 PY 2008 BP 797 EP 803 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BIT97 UT WOS:000262710700088 ER PT B AU Massad, JE Chaplya, PM Martin, JW Reu, PL Sumali, H AF Massad, Jordan E. Chaplya, Pavel M. Martin, Jeffrey W. Reu, Phillip L. Sumali, Hartono GP ASME TI Nonlinear deflection model for corner-supported, thin laminates shape-controlled with moment actuators SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 10, PTS A AND B: MECHANICS OF SOLIDS AND STRUCTURES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 10-16, 2007 CL Seattle, WA SP Amer Soc Mech Engineers ID SEGMENTED INPLANE ACTUATORS; FUNCTIONALLY GRADED PLATES AB The shape control of thin, flexible structures has been studied primarily for edge-supported thin-plates. For applications such as electromagnetic wave reflectors, corner-supported configurations may prove more applicable since they allow for greater flexibility and larger achievable deflections when compared to edge-supported geometries under similar actuation conditions. Models of such structures provide insight for effective, realizable designs, enable design optimization, and provide a means of active shape control. Models for small deformations of corner-supported, thin laminates actuated by integrated piezoelectric actuators have been developed. However, membrane deflections expected for nominal actuation exceed those stipulated by linear, small deflection theories. In addition, large deflection models have been developed for membranes; however these models are not formulated for shape control. This paper extends a previously-developed linear model for a corner-supported thin, rectangular laminate to a more general large deflection model for a clamped-corner laminate composed of moment actuators and an array of actuating electrodes. First, a nonlinear model determining the deflected shape of a laminate given a distribution of actuation voltages is derived. Second, a technique is employed to formulate the model as a map between input voltage and deflection alone, making it suitable for shape control. Finally, comparisons of simulated deflections with measured deflections of a fabricated active laminate are investigated. C1 [Massad, Jordan E.; Chaplya, Pavel M.; Martin, Jeffrey W.; Reu, Phillip L.; Sumali, Hartono] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Massad, JE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM jemassa@sandia.gov NR 12 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4304-8 PY 2008 BP 243 EP 252 PG 10 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA BHO84 UT WOS:000254907300027 ER PT B AU Robbins, J Chaplya, PM AF Robbins, Joshua Chaplya, Pavel M. GP ASME TI Modeling of nonlinear material behavior in microstructurally engineered ferroelectric ceramics SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 10, PTS A AND B: MECHANICS OF SOLIDS AND STRUCTURES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB Ferroelectric ceramics can be tailored at the microscale to have an ordered arrangement of crystal axes. Such grain-oriented ceramics can exhibit material properties far superior to conventional ceramics with random microstructure. A microstructurally based numerical model has been developed that describes the 3D non-linear behavior of ferroelectric ceramics. The model resolves the polycrystalline structure directly in the topology of the problem domain. The developed model is used to predict the effect of microstructural modifications on material behavior In particular we examine the internal residual stress after poling for idealized configurations of random and grain-oriented microstructures. The results indicate that a grain-ordered microstructure produces a significant increase in remanent polarization without detriment to internal residual stress. C1 [Robbins, Joshua] Sandia Natl Labs, Multiscale Dynam Mat Modeling, Albuquerque, NM 87123 USA. RP Robbins, J (reprint author), Sandia Natl Labs, Multiscale Dynam Mat Modeling, Albuquerque, NM 87123 USA. NR 7 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4304-8 PY 2008 BP 375 EP 379 PG 5 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA BHO84 UT WOS:000254907300042 ER PT B AU Luketa-Hanlin, A Attaway, S AF Luketa-Hanlin, Anay Attaway, Stephen GP ASME TI Massively parallel computations of damage to a thin-walled structure from blast SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 10, PTS A AND B: MECHANICS OF SOLIDS AND STRUCTURES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB The objective of this work is to determine initial structural response from a blast threat for the newer class of liquefied natural gas (LNG) vessels. Import of LNG by ship is expected to significantly increase in the coming decade and there is concern over vulnerability. Current vessels hold up to 160,000 m(3) of LNG, while the new vessels will hold up to 266,000 m3. These vessels are double-hulled and have an insulating containment system which keeps the LNG at a temperature of 111 K. Calculations were performed to determine the structural response of these ships from blast using CTH, a shock-physics code, developed at Sandia National Laboratories. The calculations were performed on massively parallel computing platforms (similar to 1000 processors) due to the number of elements required (similar to 10(9)). Detailed geometry of the stiffeners, framing, and changing hull thickness with elevation were included, as well as the insulation, LNG, and water. Thus, there is multi-phase interaction with the structure. The geometry of these ships fall within a class of problems termed 'thin-walled problems' since they require resolution of length scales from similar to 10 mm to similar to 10 m. In order to capture the smallest length scales an adaptive mesh refinement (AMR) feature was used. This feature allows for cells to be concentrated in active regions as the calculation progresses. This paper will discuss the resolution challenges of simulating thin-walled problems, as well as regimes in which shock-physics codes, such as CTH, are appropriate for application. Results will be provided without disclosure of threats. C1 [Luketa-Hanlin, Anay; Attaway, Stephen] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Luketa-Hanlin, A (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4304-8 PY 2008 BP 887 EP 891 PG 5 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA BHO84 UT WOS:000254907300101 ER PT B AU Jin, H Lu, WY Hong, SS Connelly, K Korellis, J AF Jin, Helena Lu, Wei-Yang Hong, Soonsung Connelly, Kevin Korellis, John GP ASME TI Fracture behavior of polyurethane foams SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 10, PTS A AND B: MECHANICS OF SOLIDS AND STRUCTURES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers DE polyurethane (PU) foam; SENB; SENT; DIC AB Due to their high energy absorption capabilities, polyurethane (PU) foams have been widely used in many applications. The mechanical behavior of Polyurethane (PU) foams has been attracting the attention from engineers and researchers. But most of work was to study the compressive behavior of PU foams. Very little knowledge is available about the fracture behavior of the PU foams. In this paper, single edge notch bend (SENB) and single edge notch tension (SENT) tests are conducted to study the mode-I fracture behavior of a rigid closed cell PU foam, PMDI 20, with a nominal density of 20 pcf (320 kg/m(3)). The stress intensity factor K-IC is calculated from the loading curves. The displacement and strain field around the crack tip is obtained using digital image correlation (DIC) technique. C1 [Jin, Helena; Lu, Wei-Yang; Hong, Soonsung; Connelly, Kevin; Korellis, John] Sandia Natl Labs, Mech Mat Dept, Livermore, CA 94550 USA. RP Jin, H (reprint author), Sandia Natl Labs, Mech Mat Dept, MS 9409, Livermore, CA 94550 USA. NR 9 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4304-8 PY 2008 BP 951 EP 954 PG 4 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA BHO84 UT WOS:000254907300109 ER PT B AU Qu, J Feng, ZL Xu, HB Frederick, DA Jolly, BC David, SA AF Qu, Jun Feng, Zhili Xu, Hanbing Frederick, D. Alan Jolly, Brian C. David, Stan A. GP ASME TI Producing a composite surface using friction stir processing SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 13: PROCESSING AND ENGINEERING APPLICATIONS OF NOVEL MATERIALS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers ID METAL-MATRIX COMPOSITES; REINFORCED ALUMINUM; SIZE AB Aluminum alloys would have much wider usage in bearing applications if their wear-resistance could be significantly improved. This investigation developed a solid-state surface engineering process to form an aluminum-alumina composite surface by friction stirring ceramic particles into an aluminum surface to improve the surface hardness and wear-resistance without sacrificing the bulk ductility and conductivity. Composite layers have been successfully processed on pure aluminum (Al 1100) surfaces that have a relatively uniform particle distribution with a concentration up to 25 vol% of alumina. Microscopic examination showed that particles were severely fractured during friction stir processing and, accordingly, the particle size decreased from the original 10-50 mu m to 1-5 mu m in the friction stir processed composite layer. The micro indentation hardness of the aluminum surface was increased from 0.33 to 0.70 GPa (HV) and the wear-resistance was improved by 30X when rubbing against a bearing steel. It has been demonstrated that powder placement methods and process parameters can be tailored to improve particle dispersion and surface hardness. Unlike most other surface engineering techniques, this process can form very thick layers, up to centimeters in thickness, avoiding delamination because of the inherent material continuity. C1 [Qu, Jun; Feng, Zhili; Xu, Hanbing; Frederick, D. Alan; Jolly, Brian C.; David, Stan A.] Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. RP Qu, J (reprint author), Oak Ridge Natl Lab, Div Mat Sci & Technol, Oak Ridge, TN 37831 USA. RI Feng, Zhili/H-9382-2012 OI Feng, Zhili/0000-0001-6573-7933 NR 7 TC 0 Z9 0 U1 0 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4307-9 PY 2008 BP 33 EP 36 PG 4 WC Engineering, Manufacturing; Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA BHN28 UT WOS:000254467900005 ER PT B AU Kelly, DL AF Kelly, Dana L. GP ASME TI Using copulas to model dependence in simulation risk assessment SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 14: SAFETY ENGINEERING, RISK ANALYSIS, AND RELIABILITY METHODS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB Typical engineering systems in applications with high failure consequences such as nuclear reactor plants often employ redundancy and diversity of equipment in an effort to lower the probability of failure and therefore risk. However, it has long been recognized that dependencies exist in these redundant and diverse systems. Some dependencies, such as common sources of electrical power, are typically captured in the logic structure of the risk model. Others, usually referred to as intercomponent dependencies, are treated implicitly by introducing one or more statistical parameters into the model. Such common-cause failure models have limitations in a simulation environment. In addition, substantial subjectivity is associated with parameter estimation for these models. This paper describes an approach in which system performance is simulated by drawing samples from the joint distributions of dependent variables. The approach relies on the notion of a copula distribution, a notion which has been employed by the actuarial community for ten years or more, but which has seen only limited application in technological risk assessment. The paper also illustrates how equipment failure data can be used in a Bayesian framework to estimate the parameter values in the copula model. This approach avoids much of the subjectivity required to estimate parameters in traditional common-cause failure models. Simulation examples are presented for failures in time. The open-source software package R is used to perform the simulations. The open-source software package WinBUGS is used to perform the Bayesian inference via Markov chain Monte Carlo sampling. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Kelly, DL (reprint author), Idaho Natl Lab, PO Box 1625, Idaho Falls, ID 83415 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4308-6 PY 2008 BP 81 EP 89 PG 9 WC Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BHO70 UT WOS:000254886300012 ER PT B AU Smith, CL Knudsen, JK AF Smith, Curtis L. Knudsen, James K. GP ASME TI Current status of the SAPHIRE risk analysis software SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 14: SAFETY ENGINEERING, RISK ANALYSIS, AND RELIABILITY METHODS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB As a supporting organization for risk activities at a variety of government agencies including the U.S. Nuclear Regulatory Commission' (NRC), National Aeronautics and Space Administration (NASA), and Department of Energy (DOE), the Idaho National Laboratory (INL) has been a principal developer of probabilistic risk and reliability analysis tools for over 35 years. The current state-of-the-practice has evolved to the use of the SAPHIRE software. This tool started in the mid-1980s as part of the NRC's general risk activities. In 1986, work commenced on the precursor to the SAPHIRE software - this software package was named IRRAS. While limited to the analysis of only fault trees of medium size, version I of IRRAS was the initial step in the progress that today has led to the SAPHIRE software, software that is capable of running on multiple processors simultaneously and is able to handle extremely complex analyses. SAPHIRE has been designed to handle large fault trees, where a tree may have up to 64,000 basic events and gates. To handle the fault trees, two mechanisms for developing and modifying the fault tree are available - a graphical editor and a hierarchical logic editor. In risk applications, there are two predominant event tree analysis methods, the "large event tree" approach and the "fault tree linking" approach. A couple of key identifying attributes of the large event tree approach is that the number of accident sequences becomes very large (measured in the millions or more) and the event tree branches are represented by probability values. For the fault tree linking approach, the number of sequences is low and fault trees represent the event tree branch points. The INL has designed SAPHIRE to handle both event tree methods. SAPHIRE uses logic models to determine minimal cut sets. Once the dominant cut sets are determined, the group of cut sets must be quantified to determine the overall probability of frequercy. After the cut sets are generated, they are used to obtain the Importance measures for each basic event in the cut sets. The resultant cut sets are also used to propagate (using either Monte Carlo or Latin Hypercube sampling) the basic event's epistemic uncertainty. C1 [Smith, Curtis L.; Knudsen, James K.] Idaho Natl Lab, Risk Reliabil & NRC Programs, Idaho Falls, ID 83415 USA. RP Smith, CL (reprint author), Idaho Natl Lab, Risk Reliabil & NRC Programs, Idaho Falls, ID 83415 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4308-6 PY 2008 BP 91 EP 99 PG 9 WC Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BHO70 UT WOS:000254886300013 ER PT B AU Coles, GA AF Coles, Garill A. GP ASME TI Prospective system assessment used to enhance patient safety case studies from a collbaoration of enginners and hospitals in Southwest Washington State SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 14: SAFETY ENGINEERING, RISK ANALYSIS, AND RELIABILITY METHODS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB It is no secret that healthcare, in general, has become art increasingly complicated mixture of technical systems complex processes and intricate skilled human interactions, Patient care processes have followed this same trend. The healthcare Industry, itself. has acknowledged that it is fraught with high-risk and error prone processes and cite medication management systems. invasive procedures and diagnostic methods. Complexity represents opportunity for unanticipated events, process failures and undesirabic outcomes. Traditionally a patierit care process fails, accountability was focused on the individual clinician error. However increasing, healthcare is following the lead of other high-risk industries (e.g, chemical, aerospace. nuclear, etc.) that attention to the characteristics the overall system that contribute to the failure. The focus has shifted to identification of systematic weaknesses and vulnerabilities. Increasing the healthcare industry is using prospective system assessment methods to evaluate the hi-h-risk systems and processes. This paper describes results of collaboration between engineers and community hospitals in Southwest Washington State between 2002 and 2007, in applying prospective system assessment methods to a range of the high-risk healthcare systems and processes. The methods used are Failure Mode Effects and Criticality Analysis and Probabilistic Risk Assessment. The two case studies presented are: 1) an hospital,hospital FMEA oil patient transfer and 2) a risk assessment of mental health patients Who present themselves in a hospital Emergency Department. C1 Battelle Pacific NW Div, Richland, WA 99352 USA. RP Coles, GA (reprint author), Battelle Pacific NW Div, Richland, WA 99352 USA. NR 12 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4308-6 PY 2008 BP 117 EP 125 PG 9 WC Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BHO70 UT WOS:000254886300016 ER PT B AU Young, J Lowry, P Schmitt, B Sullivan, R Mahoney, L Ryan, G AF Young, Jonathan Lowry, Pete Schmitt, Bruce Sullivan, Robin Mahoney, Lenna Ryan, Grant GP ASME TI Safety basis design development challenges SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 14: SAFETY ENGINEERING, RISK ANALYSIS, AND RELIABILITY METHODS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB "Designing in Safety" is a desired part of the development of any new potentially hazardous system, process, or facility. It is a required part of nuclear safety activities as specified in the U.S. Department of Energy (DOE) Order 420.1B, Facility Safety. This order addresses the design of nuclear related facilities developed under federal regulation 10CFR830, Nuclear Safety Management. 10CFR830 requires that safety basis documentation be provided to identify how nuclear safety is being adequately addressed as a condition for system operation (e.g., the safety basis). To support the development of the safety basis, a safety analysis is performed. Although the concept of developing a design that addresses safety is simple, the execution can be complex and challenging. This paper addresses those complexities and challenges for the design activity of a system to treat sludge, a corrosion product of spent nuclear fuel, at DOE's Hanford Site in Washington State. The system being developed is referred to as the Sludge Treatment Project (STP). This paper describes the portion of the safety analysis that addresses the selection of design basis events using the experience gained from the STP and the development of design requirements for safety features associated with those events. Specifically, the paper describes the safety design process and the application of the process for two types of potential design basis accidents associated with the operation of the system, 1) flashing spray leaks and 2) splash and splatter leaks. Also presented are the technical challenges that are being addressed to develop effective safety features to deal with these design basis accidents. C1 [Young, Jonathan; Lowry, Pete; Schmitt, Bruce; Sullivan, Robin; Mahoney, Lenna] Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. RP Young, J (reprint author), Pacific NW Natl Lab, Environm Technol Div, PO Box 999, Richland, WA 99352 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4308-6 PY 2008 BP 126 EP 131 PG 6 WC Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BHO70 UT WOS:000254886300017 ER PT B AU Coles, GA Zentner, MD AF Coles, Garill A. Zentner, Michael D. GP ASME TI Apllication of event tree/fault tree modeling approach to the evaluation of proliferation resistance SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 14: SAFETY ENGINEERING, RISK ANALYSIS, AND RELIABILITY METHODS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB With the increasing popularity of nuclear energy as a means to address dwindling fossil resources and generation of greenhouse gases, comes a concern over the potential for increased proliferation of nuclear materials. Newly proposed processes/facilitics will require an efficient, timely, and systematic assessment of the potential for proliferation to support decisions about optimum solutions to these competing concerns. currently, evaluation of proliferation resistance is largely done by experts in an informal and unstructured fashion. As a result the evaluation may not always be repeatable or supportable. In 2002 an expert group was formed by The Generation IV, International Forum to develop an internationally accepted methodology for assessing the proliferation resistance of a nuclear energy system (NES) and its individual elements. A pilot study was performed to test the methodologies being developed. The pilot consisted of assessing proliferation resistance of a specific NES example with each analysis method. The example chosen was called the Example Sodium Fast Reactor which was designed to accept spent sodium-bonded, metallic fuel from four advanced fast reactors and to convert it into new fuel assemblies. A number of different approaches were taken to evaluate the diversion of material from the facility to assess their applicability and usefulness. This paper describes a Decision Event Tree and Fault Tree Analysis approach. C1 [Coles, Garill A.; Zentner, Michael D.] Battelle Pacific NW Natl Lab, Richland, WA 99352 USA. RP Coles, GA (reprint author), Battelle Pacific NW Natl Lab, Richland, WA 99352 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4308-6 PY 2008 BP 139 EP 147 PG 9 WC Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BHO70 UT WOS:000254886300019 ER PT B AU Hightower, M AF Hightower, Mike GP ASME TI Emerging energy development demands on water SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 15: SUSTAINABLE PRODUCTS AND PROCESSES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB Currently, electric power generation is one of the largest water withdrawal and use sectors in the U.S. Additionally, future energy development such as biofuels production, hydrogen fuel or synthetic fuels production, oil shale development, carbon sequestration, or nuclear power development could significantly increase water use and consumption. On the other hand, water resource development - distribution, treatment, and transmission - is one of the largest energy use sectors. As future demands for energy and water continue to increase, competition for water between the energy, domestic, agricultural, and industrial sectors, could significantly impact the availability of water supplies for energy development, thus impacting reliability and security of future energy production and electric power generation. Therefore, it is critical that water and energy resources planning and development be integrated and coordinated across state and regional boundaries. This paper provides a short overview of the emerging energy-water challenges and issues identified in a recent series of national workshops on energy and water related issues as well as summarizing the research and development needs to address these emerging energy and water challenges. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hightower, M (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4309-3 PY 2008 BP 149 EP 154 PG 6 WC Engineering, Mechanical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BHO69 UT WOS:000254885600017 ER PT B AU Stoots, C O'Brien, J Hartvigsen, J AF Stoots, C. O'Brien, J. Hartvigsen, J. GP ASME TI Carbon neutral production of syngas via high temperature electrolytic reduction of steam and CO2 SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 15: SUSTAINABLE PRODUCTS AND PROCESSES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB This paper presents the most recent results of experiments conducted at the Idaho National Laboratory (INL) studying coelectrolysis of steam and carbon dioxide in solid-oxide electrolysis stacks. Two 10-cell planar stacks were tested under various gas compositions, operating voltages, and operating temperatures. The tests were heavily instrumented, and outlet gas compositions were monitored with a gas chromatograph. Measured outlet compositions, open cell potentials, and coelectrolysis thermal neutral voltages compared reasonably well with a coelectrolysis computer model developed at the INL. Stack ASRs did not change significantly when switching from electrolysis to coelectrolysis operation. C1 [Stoots, C.; O'Brien, J.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Stoots, C (reprint author), Idaho Natl Lab, 2525 Fremont Ave,MS 3890, Idaho Falls, ID 83415 USA. NR 8 TC 0 Z9 0 U1 1 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4309-3 PY 2008 BP 185 EP 194 PG 10 WC Engineering, Mechanical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BHO69 UT WOS:000254885600022 ER PT B AU Zaltash, A Petrov, A Linkous, R Vineyard, E Goodnack, D Egilegor, B AF Zaltash, Abdolreza Petrov, Andrei Linkous, Randall Vineyard, Edward Goodnack, David Egilegor, Bakarne GP ASME TI Performance evaluation of a 4.5 kW (1.3 refrigeration tons) air-cooled lithium bromide/water hot-water-fired absorption unit SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 15: SUSTAINABLE PRODUCTS AND PROCESSES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB During the summer months, air-conditioning (cooling) is the single largest use of electricity in both residential and commercial buildings with the major impact on peak electric demand. Improved air-conditioning technology has by far the greatest potential impact on the electric industry compared to any other technology that uses electricity. Thermally activated absorption air-conditioning (absorption chillers) can provide overall peak load reduction and electric grid relief for summer peak demand. This paper describes an innovative absorption technology based on integrated rotating heat exchangers to enhance heat and mass transfer resulting in a potential reduction of size, cost, and weight of the "next generation" absorption units. This absorption chiller (RAC) is a 4.5 kW (1.3 refrigeration tons or RT) air-cooled lithium bromide (LiBr)/water unit powered by hot water generated using the solar energy and/or waste heat. Typically LiBr/water absorption chillers are water-cooled units which use a cooling tower to reject heat. Cooling towers require a large amount of space and increase start-up and maintenance costs. However, RAC is an air-cooled absorption chiller which requires no cooling tower. The purpose of this evaluation is to verify RAC performance by comparing the Coefficient of Performance (COP or ratio of cooling capacity to thermal energy input) and the cooling capacity results with those of the manufacturer. The performance of the RAC was tested at Oak Ridge National Laboratory (ORNL) in a controlled environment at various hot and chilled water flow rates, air handler flow rates, and ambient temperatures. Temperature probes, mass flow meters, rotational speed measuring device, pressure transducers, and a web camera mounted inside the unit were used to monitor the RAC via a web control-based data acquisition system using Automated Logic Controller (ALC). Results showed a COP and cooling capacity of approximately 0.58 and 3.7 kW respectively at 35 degrees C (95 degrees F) design condition for ambient temperature with 40 degrees C (104 degrees F) cooling water temperature. This is in close agreement with the manufacturer data of 0.60 for COP and 3.9 kW for cooling capacity. Future work will use these performance results to evaluate the potential benefits of rotating heat exchangers in making the "next-generation" absorption chillers more compact and cost effective without any significant degradation in the performance. Future studies will also evaluate the feasibility of using rotating heat exchangers in other applications. C1 [Zaltash, Abdolreza] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Zaltash, A (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Vineyard, Edward/0000-0003-4695-7441 NR 11 TC 0 Z9 0 U1 0 U2 8 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4309-3 PY 2008 BP 197 EP 210 PG 14 WC Engineering, Mechanical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BHO69 UT WOS:000254885600023 ER PT B AU Geoghegan, P Petrov, A Vineyard, E Linkous, R Zaltash, A AF Geoghegan, Patrick Petrov, Andrei Vineyard, Edward Linkous, Randall Zaltash, Abdolreza GP ASME TI Frost growth CFD model of an integrated active desiccant rooftop unit SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 15: SUSTAINABLE PRODUCTS AND PROCESSES LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers ID TUBE HEAT-EXCHANGERS; AIR; PERFORMANCE; FIN AB A frost growth model is incorporated into a Computational Fluid Dynamics (CFD) simulation of a heat pump by means of a user-defined function in a commercial CFD code. The transient model is applied to the outdoor section of an Integrated Active Desiccant Rooftop (IADR) unit in heating mode. IADR is a hybrid vapor compression and active desiccant unit capable of handling 100% outdoor air (dedicated outdoor air system) or as a total conditioning system, handling both outdoor air and space cooling or heating loads. The predicted increase in flow resistance and loss in heat transfer capacity due to frost build-up are compared to experimental pressure drop readings and thermal imaging. The purpose of this work is to develop a CFD model that is capable of predicting frost growth, a potentially valuable tool in evaluating the effectiveness of defrost-on-demand cycles. C1 [Geoghegan, Patrick; Petrov, Andrei; Vineyard, Edward; Linkous, Randall; Zaltash, Abdolreza] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Geoghegan, P (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Vineyard, Edward/0000-0003-4695-7441 NR 15 TC 0 Z9 0 U1 0 U2 4 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4309-3 PY 2008 BP 211 EP 217 PG 7 WC Engineering, Mechanical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BHO69 UT WOS:000254885600024 ER PT B AU Hinnerichs, T Scherzinger, W Neilsen, M Carne, T Stasiunas, E Lu, WY AF Hinnerichs, Terry Scherzinger, William Neilsen, Mike Carne, Tom Stasiunas, Eric Lu, We-Yang GP ASME TI Validation of a new aluminum honeycomb crush model with dynamic impact tests SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 16: TRANSPORTATION SYSTEMS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB This paper describes a process for validating a new constitutive model for large, high strain-rate deformation of aluminum honeycomb, called the Honeycomb Crush Model (HCM). This model has 6 yield surfaces that are coupled to account for the orthotropic behavior of the cellular honeycomb being crushed on-axis and off-axis. The HCM has been implemented in the transient dynamic Presto finite element code for dynamic impact simulations. The HCM constitutive parameters were identified based on Presto finite element models that were used to simulate uniaxial and biaxial crush tests of 38 lb/ft(3) aluminum honeycomb and reported in an earlier paper. This paper focuses on validating the HCM in the Presto code for application to impact situations that have honeycomb crush velocities up to 85 ft/sec. Also, a new approach for incorporating rate sensitivity into the model is described. A two-stage energy absorber with integrated aluminum honeycomb is described as the configuration for dynamic impact validation experiments. The test parameters and finite element model will be described along with the uncertainty quantification that was done and propagated through the model. Finally, correlation of model predictions and test results will be presented using an energy based validation metric. C1 [Hinnerichs, Terry; Scherzinger, William; Neilsen, Mike; Carne, Tom; Stasiunas, Eric] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hinnerichs, T (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4310-9 PY 2008 BP 363 EP 383 PG 21 WC Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BHP15 UT WOS:000255101700041 ER PT B AU Layne, AW Alvin, MA Granite, E Pennline, HW Siriwardane, RV Keairns, D Newby, R AF Layne, Abbie W. Alvin, Mary Anne Granite, Evan Pennline, Henry W. Siriwardane, Ranjani V. Keairns, Dale Newby, Richard GP ASME TI Overview of contaminant removal from coal-derived syngas SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 6: ENERGY SYSTEMS: ANALYSIS, THERMODYNAMICS AND SUSTAINABILITY LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers ID SORBENTS; GAS AB Gasification is an important strategy for increasing the utilization of abundant domestic coal reserves. DOE envisions increased use of gasification in the United States during the next 20 years. As such, the DOE Gasification Technologies Program, including the FutureGen initiative, will strive to approach a near-zero emissions goal, with respect to multiple pollutants, such as sulfur, mercury, and nitrogen oxides. Since nearly one-third of anthropogenic carbon dioxide emissions are produced by coal-powered generation facilities, conventional coal-burning power plants, and advanced power generation plants, such as IGCC, present opportunities in which carbon can be removed and then permanently stored. Gas cleaning systems for IGCC power generation facilities have been effectively demonstrated and used in commercial operations for many years. These systems can reduce sulfur, mercury, and other contaminants in synthesis gas produced by gasifiers to the lowest level achievable in coal-based energy systems. Currently, DOE Fossil Energy's goals set for 2010 direct completion of R&D for advanced gasification combined cycle technology to produce electricity from coal at 45-50% plant efficiency. By 2012, completion of R&D to integrate this technology with carbon dioxide separation, capture, and sequestration into a zero-emissions configuration is targeted with a goal to provide electricity with less than a 10% increase in cost of electricity. By 2020, goals are set to develop zero-emissions plants that are fuel-flexible and capable of multi-product output and thermal efficiencies of over 60% with coal. These objectives dictate that it is essential to not only reduce contaminant emissions into the generated synthesis gas, but also to increase the process or system operating temperature to that of humid gas cleaning criteria conditions (150 to 370 degrees C), thus reducing the energy penalties that currently exist as a result of lowering process temperatures (-40 to 38 degrees C) with subsequent reheat to the required higher temperatures. From a historical perspective, the evolution of advanced syngas cleaning systems applied in IGCC and chemical and fuel synthesis plants has followed a path of configuring a series of individual cleaning steps, one for each syngas contaminant, each step controlled to its individual temperature and sorbent and catalyst needs. As the number of syngas contaminants of interest has increased (particulates, hydrogen sulfide, carbonyl sulfide, halides such as hydrogen chloride, ammonia, hydrogen cyanide, alkali metals, metal carbonyls, mercury, arsenic, selenium, and cadmium) and the degree of syngas cleaning has become more severe, the potential feasibility of advanced humid gas cleaning has diminished. A focus on multi-contaminant syngas cleaning is needed to enhance the potential cost savings, and performance of humid gas cleaning will focus on multi-contaminant syngas cleaning. Groups of several syngas contaminants to be removed simultaneously need to be considered, resulting in significant gas cleaning system intensification. Intensified, multi-contaminant cleaning processes need to be devised and their potential performance characteristics understood through small-scale testing, conceptual design evaluation, and scale-up assessment with integration into the power generation system. Results of a 1-year study undertaken by DOE/NETL are presented to define improved power plant configurations and technology for advanced multi-contaminant cleanup options. C1 [Layne, Abbie W.] US DOE, NETL, Seperat & Fuels Proc Div, Morgantown, WV 26507 USA. RP Layne, AW (reprint author), US DOE, NETL, Seperat & Fuels Proc Div, 3610 Collins Ferry Rd,POB 880, Morgantown, WV 26507 USA. NR 17 TC 0 Z9 0 U1 2 U2 9 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4300-0 PY 2008 BP 397 EP 407 PG 11 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BHN34 UT WOS:000254474800043 ER PT B AU Kearney, SP Grasser, TW AF Kearney, Sean P. Grasser, Thomas W. GP ASME TI Cars probing of meter-scale turbulent pool fires SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 6: ENERGY SYSTEMS: ANALYSIS, THERMODYNAMICS AND SUSTAINABILITY LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers ID TEMPERATURE AB We report an application of coherent anti-Stokes Raman scattering (CARS) to full-scale fire testing. A CARS instrument has been constructed at the newly commissioned FLAME (Fire Laboratory for Accreditation of Models and Experiments) facility at Sandia, where the CARS system has been used for thermometry in 2-m-diameter, turbulent pool fires. The details of a CARS instrument for probing the challenging pool-fire environment are presented, along with the construction of the unique new FLAME facility itself, which has been designed to accommodate optical and laser-based diagnostics to full-scale fire experimentation. Single-shot CARS spectra and best-fit temperatures from turbulent pool fires are presented, and an estimate of the pdf of the temperature fluctuations from the pool-fire environment is obtained. C1 [Kearney, Sean P.; Grasser, Thomas W.] Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. RP Kearney, SP (reprint author), Sandia Natl Labs, Engn Sci Ctr, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4300-0 PY 2008 BP 427 EP 430 PG 4 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BHN34 UT WOS:000254474800047 ER PT B AU Forsberg, C AF Forsberg, Charles GP ASME TI An air-Brayton nuclear-hydrogen combined-cycle peak-and base-load electric plant SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 6: ENERGY SYSTEMS: ANALYSIS, THERMODYNAMICS AND SUSTAINABILITY LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB A combined-cycle power plant is proposed that uses heat from a high-temperature nuclear reactor and hydrogen produced by the high-temperature reactor to meet base-load and peak-load electrical demands. For base-load electricity production, air is compressed; flows through a heat exchanger, where it is heated to between 700 and 900 degrees C; and exits through a high-temperature gas turbine to produce electricity. The heat, via an intermediate heat-transport loop, is provided by a high-temperature reactor. The hot exhaust from the Brayton-cycle turbine is then fed to a heat recovery steam generator that provides steam to a steam turbine for added electrical power production. To meet peak electricity demand, after nuclear heating of the compressed air, hydrogen is injected into the combustion chamber, combusts, and heats the air to 1300 degrees C-the operating conditions for a standard natural-gas-fired combined-cycle plant. This process increases the plant efficiency and power output. Hydrogen is produced at night by electrolysis or other methods using energy from the nuclear reactor and is stored until needed. Therefore, the electricity output to the electric grid can vary from zero (i.e., when hydrogen is being produced) to the maximum peak power while the nuclear reactor operates at constant load. Because nuclear heat raises air temperatures above the auto-ignition temperatures of the hydrogen and powers the air compressor, the power output can be varied rapidly (compared with the capabilities of fossil-fired turbines) to meet spinning reserve requirements and stabilize the grid. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Forsberg, C (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 14 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4300-0 PY 2008 BP 561 EP 567 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BHN34 UT WOS:000254474800064 ER PT B AU McKellar, MG O'Brien, JE Stoots, CM Hawkes, GL AF McKellar, M. G. O'Brien, J. E. Stoots, C. M. Hawkes, G. L. GP ASME TI Process model for the production of syngas via high temperature co-electrolysis SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 6: ENERGY SYSTEMS: ANALYSIS, THERMODYNAMICS AND SUSTAINABILITY LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB A process model has been developed to evaluate the potential performance of a large-scale high-temperature co-electrolysis plant for the production of syngas from steam and carbon dioxide. The co-electrolysis process allows for direct electrochemical reduction of the steam - carbon dioxide gas mixture, yielding hydrogen and carbon monoxide, or syngas. The process model has been developed using the Honeywell UniSim systems analysis code. Using this code, a detailed process flow sheet has been defined that includes all the components that would be present in an actual plant such as pumps, compressors, heat exchangers, turbines, and the electrolyzer. Since the electrolyzer is not a standard UniSim component, a custom one-dimensional co-electrolysis model was developed for incorporation into the overall UniSim process flow sheet. The one dimensional co-electrolysis model assumes local chemical equilibrium among the four process-gas species via the gas shift reaction. The electrolyzer model allows for the determination of co-electrolysis outlet temperature, composition (anode and cathode sides); mean Nernst potential, operating voltage and electrolyzer power based on specified inlet gas flow rates, heat loss or gain, current density, and cell area-specific resistance. The one-dimensional electrolyzer model was validated by comparison with results obtained from a fully three dimensional computational fluid dynamics model developed using FLUENT, and by comparison to experimental data. This paper provides representative results obtained from the UniSim flow sheet model for a 300 MW co-electrolysis plant, coupled to a high-temperature gas-cooled nuclear reactor. The co-electrolysis process, coupled to a nuclear reactor, provides a means of recycling carbon dioxide back into a useful liquid fuel. If the carbon dioxide source is based on biomass, the entire process would be climate neutral. C1 [McKellar, M. G.; O'Brien, J. E.; Stoots, C. M.; Hawkes, G. L.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP McKellar, MG (reprint author), Idaho Natl Lab, Idaho Falls, ID 83415 USA. OI Hawkes, Grant/0000-0003-3496-8100 NR 8 TC 0 Z9 0 U1 2 U2 4 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4300-0 PY 2008 BP 691 EP 699 PG 9 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA BHN34 UT WOS:000254474800078 ER PT B AU Bamberger, JA Meyer, PA Bontha, JR Fort, JA Nigi, F Bates, JM Enderlin, CW Yokuda, ST Kurath, DE Poloski, AP Smith, HD Smith, GL Gerber, MA AF Bamberger, Judith Ann Meyer, Perry A. Bontha, Jagan R. Fort, James A. Nigi, Franz Bates, James M. Enderlin, Carl W. Yokuda, Sato T. Kurath, Dean E. Poloski, Adam P. Smith, Harry D. Smith, Gary L. Gerber, Mark A. GP ASME TI Evaluating pulse jet mixing with non-Newtonian slurries SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION 2007, VOL 8, PTS A AND B: HEAT TRANSFER, FLUID FLOWS, AND THERMAL SYSTEMS LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers AB Pulse jet mixer technology has been selected for implementation in the Hanford Waste Treatment Plant. However, processing non-Newtonian fluids using this technology is not mature. Experiments were conducted at several scales to develop an understanding of the scaling mechanisms that govern this type of mixer performance. C1 [Bamberger, Judith Ann; Meyer, Perry A.] Battelle Pacific NW Div, Richland, WA 99352 USA. RP Bamberger, JA (reprint author), Battelle Pacific NW Div, Richland, WA 99352 USA. NR 9 TC 0 Z9 0 U1 1 U2 4 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4302-4 PY 2008 BP 1909 EP 1930 PG 22 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA BHN64 UT WOS:000254515301094 ER PT B AU Robinett, RD Wilson, DG AF Robinett, Rush D., III Wilson, David G. GP ASME TI Decentralized exergy/entropy thermodynamic control for collective robotic systems SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINERING CONGRESS AND EXPOSITION 2007, VOL 9, PTS A-C: MECHANICAL SYSTEMS AND CONTROL LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers ID VEHICLES AB This paper develops a distributed decentralized control law for collective robotic systems. The control laws are developed based on exergy/entropy thermodynamic concepts and information theory. The source field is characterized through second-order accuracy. The proposed feedback control law stability for both the collective and individual robots are demonstrated by selecting a general Hamiltonian based solution developed as Fisher Information Equivalency as the vector Lyapunov function. Stability boundaries and system performance are then determined with Lyapunov's direct method. A robot collective plume tracing numerical simulation example demonstrates this decentralized exergy/entropy collective control architecture. C1 [Robinett, Rush D., III; Wilson, David G.] Sandia Natl Labs, Energy Res & Anal Ctr, Albuquerque, NM 87185 USA. RP Wilson, DG (reprint author), Sandia Natl Labs, Energy Res & Anal Ctr, POB 5800, Albuquerque, NM 87185 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4303-1 PY 2008 BP 1447 EP 1453 PG 7 WC Automation & Control Systems; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BHN65 UT WOS:000254515900168 ER PT B AU Leishear, RA Stefanko, DB Newton, JD AF Leishear, Robert A. Stefanko, David B. Newton, Jerald D. GP ASME TI Excitation of structural resonance due to a bearing failure SO PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINERING CONGRESS AND EXPOSITION 2007, VOL 9, PTS A-C: MECHANICAL SYSTEMS AND CONTROL LA English DT Proceedings Paper CT ASME International Mechanical Engineering Congress and Exposition CY NOV 11-15, 2007 CL Seattle, WA SP Amer Soc Mech Engineers DE resonance; bearing failure; vibration analysis; centrifugal pump AB Vibration due to a bearing failure in a pump created significant vibrations in a fifteen foot by fifteen foot by eight feet tall mounting platform due to excitation of resonant frequencies. In this particular application, an 18,000 pound pump was mounted to a structural steel platform. When bearing damage commenced, the platform vibrated with sufficient magnitude that conversations could not be heard within forty feet of the pump. Vibration analysis determined that the frequency of the bearing was coincident to one of the natural frequencies of the pump, which was, in turn, coincident to one of the natural frequencies of the mounting platform. This coincidence of frequencies defines resonance. Resonance creates excessive vibrations when the natural frequency of a structure is coincident to an excitation frequency. In this well documented case, the excitation frequency was related to ball bearing failures. The pump is a forty foot long vertical pump used to mix nuclear waste in 1,300,000 gallon tanks. A 300 horsepower drive motor is mounted to a structural steel platform on top of the tank. The pump hangs down into the tank from above to mix the waste and is inaccessible after installation. Initial awareness of the problem was due to increased noise from the pump. Initial vibration analysis indicated that the vibration levels of the bearing were within the expected range for this type of bearing, and the resonant condition was not obvious. Further analysis consisted of disassembly of the motor to inspect the bearings and extensive vibration monitoring. Vibration data for the bearings was obtained from the manufacturer and compared to measured vibration plots for the pump and mounting platform. Vibration data measured along the length of the pump was available from full scale testing, and vibrations were also measured at the installed pump. One of the axial frequencies of the pump, the platform frequency in the vertical direction, and the ball spin frequency for the bearing were multiples of each other. This resonant condition was detected before other damage occurred, and further damage due to the resonant condition was prevented through vibration analysis. C1 [Leishear, Robert A.; Stefanko, David B.; Newton, Jerald D.] Washington Savannah River Co, Savannah River Natl Lab, Aiken, SC 29803 USA. RP Leishear, RA (reprint author), Washington Savannah River Co, Savannah River Natl Lab, Aiken, SC 29803 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4303-1 PY 2008 BP 1669 EP 1677 PG 9 WC Automation & Control Systems; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BHN65 UT WOS:000254515900191 ER PT B AU VanOsdol, JG Gemmen, R Parsons, E AF VanOsdol, John G. Gemmen, Randall Parsons, Edward GP ASME TI USING STAGED COMPRESION TO INCREASE THE SYSTEM EFFICIENCY OF A COAL BASED GAS TURBINE FUEL CELL HYBRID POWER GENERATION SYSTEM WITH CARBON CAPTURE SO PROCEEDINGS OF THE ASME POWER CONFERENCE 2008 LA English DT Proceedings Paper CT ASME Power Conference 2008 CY JUL 22-24, 2008 CL Lake Buena Vista, FL SP Amer Soc Mech Engineers, Power Div AB This paper examines two coal-based hybrid configurations that employ separated anode and cathode streams for the capture and compression Of CO2. One system uses a single compressor to compress and partially preheat the cathode air flow. The second system replaces the single compressor with a two stage compression process with an intercooler to extract heat between the stages, and to reduce the work that is required to compress the air flow in the cathode stream. Calculations are presented for both systems with and without heat recuperation. For the single compressor system with heat recuperation the hybrid system assumes the form of a recuperated Brayton cycle; when the recuperator is not present the hybrid system assumes the form of a standard Brayton cycle. The calculation results show that an increase of 2.2% in system efficiency was obtained by staging the compression for these cycles. C1 [VanOsdol, John G.; Gemmen, Randall; Parsons, Edward] Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP VanOsdol, JG (reprint author), Natl Energy Technol Lab, 3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4832-6 PY 2008 BP 679 EP 689 PG 11 WC Energy & Fuels; Engineering, Mechanical; Transportation Science & Technology SC Energy & Fuels; Engineering; Transportation GA BIW18 UT WOS:000263292300082 ER PT B AU Maziasz, PJ Shingledecker, JP Evans, ND Pollard, MJ AF Maziasz, Philip J. Shingledecker, John P. Evans, Neal D. Pollard, Michael J. BE Jaske, CE Jaske, CE TI Developing new cast austenitic stainless steels with improved high-temperature creep resistance SO PROCEEDINGS OF THE ASME PRESSURE VESSELS AND PIPING CONFERENCE 2007, VOL 9 LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 22-26, 2007 CL San Antonio, TX SP Amer Soc Mech Engineers, Pressure Vessels & Piping Div AB Oak Ridge National Laboratory (ORNL) and Caterpillar have recently developed a new cast austenitic stainless steel, CF8C-Plus, for a wide range of high-temperature applications, including diesel exhaust components and turbine casings. The creep-rupture life of the new CF8C-Plus is over ten times greater than that of the standard cast CF8C stainless steel, and the creep-strength is about double. Another variant, CF8C-Plus Cu/W has been developed with even more creep strength at 750-850 degrees C. The creep-strength of these new cast austenitic stainless steels is close to that of Ni-based superalloys like 617. CF8C-Plus steel was developed in about 1.5 years using an "engineered microstructure" alloy development approach, which produces creep resistance based on formation of stable nano-carbides (NbC) and prevention of deleterious intermetallics (sigma, Laves). CF8C-Plus steel won a 2003 R&D 100 Award, and to date, over 32,000 lb have been produced in various commercial component trials. The current commercialization status of the alloy is summarized. C1 [Maziasz, Philip J.; Shingledecker, John P.; Evans, Neal D.] Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Maziasz, PJ (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RI Evans, Neal/F-5955-2011; OI Maziasz, Philip/0000-0001-8207-334X NR 7 TC 0 Z9 0 U1 2 U2 6 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4287-4 PY 2008 BP 73 EP 80 PG 8 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BHK63 UT WOS:000253884500009 ER PT B AU Shingledecker, JP Carter, P Battiste, RL AF Shingledecker, J. P. Carter, P. Battiste, R. L. BE Jaske, CE Jaske, CE TI Thermal shock testing and analysis of IN617 and super 304H samples SO PROCEEDINGS OF THE ASME PRESSURE VESSELS AND PIPING CONFERENCE 2007, VOL 9 LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 22-26, 2007 CL San Antonio, TX SP Amer Soc Mech Engineers, Pressure Vessels & Piping Div AB The DOE/OCDO sponsored Ultrasupercritical (USC) Steam Boiler Consortium is conducting thermal shock tests on austenitic and nickel-based materials to assess their use in thick-section boiler components. This paper describes the tests on CCA617 (a controlled chemistry version of IN617) and Super 304H thick-walled tubes. Details are given of the metallurgical analyses of the observed cracking in the bore and on the OD of the samples, and of the thermal-mechanical analyses to explain the results. Elastic-plastic and elastic-plastic-creep analyses are used to calculate damage based on rupture life and creep strain accumulation. Fatigue calculations are performed. The results of the metallurgical and mechanical analyses are compared and conclusions drawn as to the accuracy and effectiveness of available high temperature life prediction techniques. C1 [Shingledecker, J. P.; Battiste, R. L.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Shingledecker, JP (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM shingledecjp@ornl.gov; peter.carter@power.alstom.com; battisterl@ornl.gov NR 9 TC 0 Z9 0 U1 0 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4287-4 PY 2008 BP 237 EP 244 PG 8 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BHK63 UT WOS:000253884500029 ER PT B AU Totemeier, TC AF Totemeier, Terry C. BE Jaske, CE Jaske, CE TI High-temperature creep-fatigue of alloy 617 base metal and weldments SO PROCEEDINGS OF THE ASME PRESSURE VESSELS AND PIPING CONFERENCE 2007, VOL 9 LA English DT Proceedings Paper CT Pressure Vessels and Piping Conference of the American-Society-of-Mechanical-Engineers CY JUL 22-26, 2007 CL San Antonio, TX SP Amer Soc Mech Engineers, Pressure Vessels & Piping Div ID BEHAVIOR AB Creep-fatigue testing of nickel alloy 617 base metal and fusion weldments was performed at temperatures of 800 and 1000C in air in support of ASME BPV Sec III code qualification of alloy 617 for the Next-Generation Nuclear Plant. Cyclic loading was performed in strain control with a trapezoidal waveform and was fully reversed. Creep was introduced into the fatigue cycle by a hold period at maximum tensile strain which varied from 18 to 9000 seconds. Base metal specimens were machined from 20 mm thick rolled plate; weldment specimens were machined from GTAW butt-welded plate such that the loading direction was oriented transverse to the welding direction. Weld metal, heat-affected zone, and base metal were present in the reduced section of weldment specimens. Creep-fatigue lives decreased with increasing hold time for both base metal and weldments; lives of weldments were reduced relative to those of base metal. Creep-fatigue cracking in weldment specimens initiated in the weld metal. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Totemeier, TC (reprint author), Idaho Natl Lab, POB 1625,MS 2218, Idaho Falls, ID 83415 USA. NR 14 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4287-4 PY 2008 BP 255 EP 260 PG 6 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BHK63 UT WOS:000253884500031 ER PT B AU Dugger, MT Asay, DB Ohlhausen, JA Kim, SH AF Dugger, Michael T. Asay, David B. Ohlhausen, James A. Kim, Seong H. GP ASME TI Mems lubrication by tribochemical reaction SO PROCEEDINGS OF THE ASME/STLE INTERNATIONAL JOINT TRIBOLOGY CONFERENCE, PTS A AND B LA English DT Proceedings Paper CT ASME/STLE International Joint Tribology Conference CY OCT 22-24, 2007 CL San Diego, CA SP ASME, STLE ID FRICTION; SURFACE; DEVICES; WEAR AB A means of providing replenishable lubrication to rubbing silicon surfaces is demonstrated. Alcohol at a small fraction of saturation vapor pressure is introduced in a nitrogen environment. Pin-on-flat sliding experiments in this environment reveal a friction coefficient near 0.2, and absence of wear above a critical alcohol concentration. This lubrication approach was also demonstrated in microfabricated silicon machines, where the devices operated at least a factor of 104 longer without failure when alcohol vapor was present in the nitrogen gas environment, compared to devices in dry N-2 with a chemisorbed monolayer alone. When water vapor was added to the environment, vapor lubrication by alcohol was inhibited at concentration ratios of water:alcohol = 2.5: 1. C1 [Dugger, Michael T.] Sandia Natl Labs, Microsyst Mat Dept, Albuquerque, NM 87185 USA. RP Dugger, MT (reprint author), Sandia Natl Labs, Microsyst Mat Dept, Albuquerque, NM 87185 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4810-4 PY 2008 BP 873 EP 875 PG 3 WC Engineering, Mechanical SC Engineering GA BHM70 UT WOS:000254339300229 ER PT B AU Eryilmaz, OL Erdemir, A AF Eryilmaz, O. L. Erdemir, A. GP ASME TI Effect of tribochemical interactions on friction and wear of highly hydrogenated DLC films SO PROCEEDINGS OF THE ASME/STLE INTERNATIONAL JOINT TRIBOLOGY CONFERENCE, PTS A AND B LA English DT Proceedings Paper CT ASME/STLE International Joint Tribology Conference CY OCT 22-24, 2007 CL San Diego, CA SP ASME, STLE ID CARBON-FILMS AB In this paper, we attempted to elucidate the nature and extent of tribochemical interactions between sliding surfaces of highly-hydrogenated diamondlike carbon (DLC) films (containing about 40 at.% hydrogen) and correlated these findings with their friction and wear behaviors in dry and humid nitrogen environments. For the tribochemical studies, we used a time-of-flight secondary ion mass spectrometer (ToF-SIMS) in 2- and 3-D imaging modes, while for tribological tests, we used a ball-on-disk machine that was operated under a 5 N load and at sliding velocities of 0.2 to 0.3 m/s. In dry nitrogen, the DLC films provided a friction coefficient of approximate to 0.007, but in humid nitrogen, the friction coefficient 3 to 4 times higher. 3-D surface profilometry and optical microscopy did not reveal much wear on sliding ball and disk surfaces after the tests regardless of the test environment, but the 2- and 3-D ToF-SIMS images of the same surfaces revealed very rich tribochemistry for films tested in humid nitrogen but not much chemistry for those films tested in dry nitrogen. Complementary x-ray photoelectron spectroscopy of these sliding surfaces showed similar results further confirming extensive tribo-oxidation (in the forms of both C-O and C=O) of DLC surfaces tested in humid nitrogen but no major chemical changes in DLC films tested in dry nitrogen. Based on the results of surface analytical and tribological studies, we concluded that superlow friction behavior of highly hydrogenated DLC films was perhaps due to the hydrogen termination of their surface carbon atoms, while the much higher friction coefficients observed in humid nitrogen was primarily due to tribo-oxidation and/or oxygen termination of these surfaces. C1 [Eryilmaz, O. L.; Erdemir, A.] Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Eryilmaz, OL (reprint author), Argonne Natl Lab, Div Energy Syst, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4810-4 PY 2008 BP 929 EP 931 PG 3 WC Engineering, Mechanical SC Engineering GA BHM70 UT WOS:000254339300244 ER PT B AU Erdemir, A Martin, JM AF Erdemir, A. Martin, J. -M. GP ASME TI New materials and coatings for superlubricity and near-wearless sliding SO PROCEEDINGS OF THE ASME/STLE INTERNATIONAL JOINT TRIBOLOGY CONFERENCE, PTS A AND B LA English DT Proceedings Paper CT ASME/STLE International Joint Tribology Conference CY OCT 22-24, 2007 CL San Diego, CA SP ASME, STLE ID CARBON-FILMS; MOLYBDENUM-DISULFIDE; FRICTION; SURFACE; HYDROGEN AB Superlubricity is defined as a new sliding regime in which friction or resistance to sliding almost vanishes. Because of its enormous implications for a wide range of transportation and manufacturing systems, it has attracted increasing interest in recent years from both the research and industrial communities (see a recent book on this subject in Ref. 1). From a practical point of view, development and uses of new materials, coatings, and/or lubricants that can enable superlubricity in moving mechanical systems will have huge positive impact on saving energy and reducing emissions. The annual cost of friction- and wear-related losses in some of the highly industrialized nations is currently estimated to be more than 5% of their gross national products. Hence, achieving superlubricity in moving mechanical systems will also have a huge positive impact on the economical well-being of all nations. In this presentation, an overview of recent progress in superlubricty research in general and novel superlow friction coatings and solid/liquid lubricated systems in particular is provided and the prospects for achieving superlubricity in real life applications are highlighted. C1 [Erdemir, A.] Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. [Martin, J. -M.] Ecole Cent Lyon, Ecully, France. RP Erdemir, A (reprint author), Argonne Natl Lab, Div Energy Syst, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 16 TC 0 Z9 0 U1 1 U2 8 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4810-4 PY 2008 BP 1069 EP 1071 PG 3 WC Engineering, Mechanical SC Engineering GA BHM70 UT WOS:000254339300284 ER PT B AU Straub, DL Chorpening, BT Huckaby, ED Thornton, JD Fincham, WL AF Straub, D. L. Chorpening, B. T. Huckaby, E. D. Thornton, J. D. Fincham, W. L. GP ASME TI TIME-VARYING FLAME IONIZATION SENSING APPLIED TO NATURAL GAS AND PROPANE BLENDS IN A PRESSURIZED LEAN PREMIXED (LPM) COMBUSTOR SO PROCEEDINGS OF THE ASME TURBO EXPO 2008, VOL 2 LA English DT Proceedings Paper CT 53rd ASME Turbo Expo 2008 CY JUN 09-13, 2008 CL Berlin, GERMANY SP Int Gas Turbine Inst, ASME ID IONS AB In-situ monitoring of combustion phenomena is a critical need for optimal operation and control of advanced gas turbine combustion systems. The concept described in this paper is based on naturally occurring flame ionization processes that accompany the combustion of hydrocarbon fuels. Previous work has shown that flame ionization techniques may be applied to detect flashback, lean blowout, and some aspects of thermo-acoustic combustion instabilities. Previous work has focused on application of DC electric fields. By application of time-varying electric fields, significant improvements to sensor capabilities have been observed. These data have been collected in a lean premixed combustion test rig operating at 0.51-0.76 MPa (5-7.5 atm) with air preheated to 588 K (600 degrees F). Five percent of the total fuel flow is injected through the centerbody tip as a diffusion pilot. The fuel composition is varied independently by blending approximately 5% (volume) propane with the pipeline natural gas. The reference velocity through the premixing annulus is kept constant for all conditions at a nominal value of 70 m/s. The fuel-air equivalence ratio is varied independently from 0.46-0.58. Relative to the DC field version, the time-varying combustion control and diagnostic sensor (TV-CCADS) shows a significant improvement in the correlation between the measured flame ionization current and local fuel-air equivalence ratio. In testing with different fuel compositions, the triangle wave data show the most distinct change in flame ionization current in response to an increase in propane content. Continued development of this sensor technology will improve the capability to control advanced gas turbine combustion systems, and help address issues associated with variations in fuel supplies. C1 [Straub, D. L.; Chorpening, B. T.; Huckaby, E. D.; Thornton, J. D.] US DOE, Morgantown Energy Technol Ctr, Morgantown, WV 26507 USA. RP Straub, DL (reprint author), US DOE, Morgantown Energy Technol Ctr, POB 880, Morgantown, WV 26507 USA. NR 23 TC 0 Z9 0 U1 3 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4312-3 PY 2008 BP 263 EP 271 PG 9 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Marine; Engineering, Mechanical; Transportation Science & Technology SC Automation & Control Systems; Engineering; Transportation GA BIV68 UT WOS:000263201300027 ER PT B AU Cheng, RK Littlejohn, D AF Cheng, R. K. Littlejohn, D. GP ASME TI EFFECTS OF COMBUSTOR GEOMETRY ON THE FLOWFIELDS AND FLAME PROPERTIES OF A LOW-SWIRL INJECTOR SO PROCEEDINGS OF THE ASME TURBO EXPO 2008, VOL 3, PTS A AND B LA English DT Proceedings Paper CT 53rd ASME Turbo Expo 2008 CY JUN 09-13, 2008 CL Berlin, GERMANY SP Int Gas Turbine Inst, ASME ID INTENSE ISOTROPIC TURBULENCE; PREMIXED GAS-TURBINES; VELOCITY; MODERATE; BURNER AB The Low-swirl injector (LSI) is a novel dry-low NOx combustion method that is being developed for gas turbines to burn a variety of gaseous fuels including natural gas, low-Btu fuels, syngases and hydrogen. Its basic principle is described by a top level analytical model that relates the flame position to the flowfield similarity parameters and the turbulent flame speed correlation. The model was based on experimental measurements in open laboratory flames. It has been useful for guiding hardware development. As the LSI is being adapted to different engine configurations, one open question is how the combustor geometry and size affect its basic operating principle. The objective of this paper is to investigate these effects by conducting Particle Image Velocimetry (PIV) measurements in open and enclosed flames produced by a 6.35 cm diameter LSI using two quartz cylinders of 15.5 and 20 cm diameter to simulate the combustor casing. Results from 18 methane-air flames show that the enclosures do not alter the flame properties or the nearfield flow structures. The differences occur mostly in the farfield where the tighter enclosure deters the formation of a weak recirculation zone. The enclosure effects on hydrogen and hydrogen-methane flames were studies using the 20 cm cylinder. The results show that the outer recirculation zone generated at the corner of the dump plane promotes the formation of attached flames. However, the properties and nearfield flow features of the attached flames are similar to those of the lifted flames. At higher stoichiometries, the attached flame collapses to form a compact disc shaped flame that has very different flowfield structures. These results show that the enclosure effects on the LSI are strongly coupled to the fuel type and dump plane geometry but are less dependent on the enclosure size. These observations will provide the basis for developing computational methods that can be used as design tools for LSI adaptation. C1 [Cheng, R. K.; Littlejohn, D.] Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Cheng, RK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 20 TC 4 Z9 4 U1 1 U2 5 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4313-0 PY 2008 BP 393 EP 407 PG 15 WC Engineering, Aerospace; Engineering, Marine; Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BIV70 UT WOS:000263203100038 ER PT B AU Ferguson, D Richard, GA Straub, D AF Ferguson, Don Richard, Geo. A. Straub, Doug GP ASME TI FUEL INTERCHANGEABILITY FOR LEAN PREMIXED COMBUSTION IN GAS TURBINE ENGINES SO PROCEEDINGS OF THE ASME TURBO EXPO 2008, VOL 3, PTS A AND B LA English DT Proceedings Paper CT 53rd ASME Turbo Expo 2008 CY JUN 09-13, 2008 CL Berlin, GERMANY SP Int Gas Turbine Inst, ASME ID PROPANE AB In response to environmental concerns of NOx emissions, gas turbine manufacturers have developed engines that operate under lean, pre-mixed fuel and air conditions. While this has proven to reduce NOx emissions by lowering peak flame temperatures, it is not without its limitations as engines utilizing this technology are more susceptible to combustion dynamics. Although dependent on a number of mechanisms, changes in fuel composition can alter the dynamic response of a given combustion system. This is of particular interest as increases in demand of domestic natural gas have fueled efforts to utilize alternatives such as coal derived syngas, imported liquefied natural gas and hydrogen or hydrogen augmented fuels. However, prior to changing the fuel supply end-users need to understand how their system will respond. A variety of historical parameters have been utilized to determine fuel interchangeability such as Wobbe and Weaver Indices, however these parameters were never optimized for today's engines operating under lean pre-mixed combustion. This paper provides a discussion of currently available parameters to describe fuel interchangeability. Through the analysis of the dynamic response of a lab-scale Rijke tube combustor operating on various fuel blends, it is shown that commonly used indices are inadequate for describing combustion specific phenomena. C1 [Ferguson, Don; Richard, Geo. A.; Straub, Doug] US DOE, Natl Energy Technol Lab, Washington, DC 20585 USA. RP Ferguson, D (reprint author), US DOE, Natl Energy Technol Lab, Washington, DC 20585 USA. NR 18 TC 1 Z9 1 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4313-0 PY 2008 BP 973 EP 981 PG 9 WC Engineering, Aerospace; Engineering, Marine; Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BIV70 UT WOS:000263203100092 ER PT B AU Littlejohn, D Cheng, RK Noble, DR Lieuwen, T AF Littlejohn, David Cheng, Robert K. Noble, D. R. Lieuwen, Tim GP ASME TI LABORATORY INVESTIGATIONS OF LOW-SWIRL INJECTORS OPERATING WITH SYNGASES SO PROCEEDINGS OF THE ASME TURBO EXPO 2008, VOL 3, PTS A AND B LA English DT Proceedings Paper CT 53rd ASME Turbo Expo 2008 CY JUN 09-13, 2008 CL Berlin, GERMANY SP Int Gas Turbine Inst, ASME ID INTENSE ISOTROPIC TURBULENCE; PREMIXED GAS-TURBINES; FLAMES; VELOCITY; MODERATE AB The low-swirl injector (LSI) is a lean premixed combustion technology that has the potential for adaptation to fuel-flexible gas turbines operating on a variety of fuels. The objective of this study is to gain a fundamental understanding of the effect of syngas on the LSI flame behavior, the emissions and the flowfield characteristics for its adaptation to the combustion turbines in IGCC clean coal power plants. The experiments were conducted in two facilities. Open laboratory flames generated by a full size (6.35 cm) LSI were used to investigate the lean-blow off limits, emissions, and the flowfield characteristics. Verification of syngas operation at elevated temperatures and pressures were performed with a reduced scale (2.54 cm) LSI in a small pressurized combustion channel. The results show that the basic LSI design is amenable to burning syngases with Lip to 60% H-2, Syngases with high H-2 concentration have lower lean blow-off limits. From PIV measurements, the flowfield similarity behavior and the turbulent flame speeds of syngases flames are consistent with those observed in hydrocarbon and pure or diluted hydrogen flames, The NOx emissions from syngas flames show log-linear dependency on the adiabatic flame temperature and are comparable to those reported for the gaseous fuels reported previously. Successful firing of the reduced-scale LSI at 330 < T < 446 degrees F and 8 atm verified the operability of this concept at gas turbine conditions. C1 [Littlejohn, David; Cheng, Robert K.] Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Littlejohn, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 20 TC 0 Z9 0 U1 1 U2 2 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4313-0 PY 2008 BP 1001 EP 1010 PG 10 WC Engineering, Aerospace; Engineering, Marine; Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BIV70 UT WOS:000263203100095 ER PT B AU Colban, WF Thole, KA Bogard, D AF Colban, Will F. Thole, Karen A. Bogard, David GP ASME TI A FILM-COOLING CORRELATION FOR SHAPED HOLES ON A FLAT-PLATE SURFACE SO PROCEEDINGS OF THE ASME TURBO EXPO 2008, VOL 4, PTS A AND B LA English DT Proceedings Paper CT 53rd ASME Turbo Expo 2008 CY JUN 09-13, 2008 CL Berlin, GERMANY SP Int Gas Turbine Inst, ASME ID GEOMETRY AB A common method of optimizing coolant performance in gas turbine engines is through the use of shaped film-cooling holes. Despite widespread use of shaped holes, existing correlations for predicting performance are limited to narrow ranges of parameters. This study extends the prediction capability for shaped holes through the development of a physics-based empirical correlation for predicting laterally-averaged film-cooling effectiveness on a flat plate downstream of a row of shaped film-cooling holes. Existing data was used to determine the physical relationship between film-cooling effectiveness and several parameters, including; blowing ratio, hole coverage ratio, area ratio, and hole spacing. Those relationships were then incorporated into the skeleton form of an empirical correlation, using results from the literature to determine coefficients for the correlation. Predictions from the current correlation, as well as existing shaped hole correlations and a cylindrical hole correlation were compared to the existing experimental data. Results show that the current physics-based correlation yields a significant improvement in predictive capability, by expanding the valid parameter range and improving agreement with experimental data. Particularly significant is the inclusion of higher blowing ratio conditions (up to M = 2.5) into the current correlation, whereas the existing correlations worked adequately only at lower blowing ratios (M approximate to 0.5). C1 [Colban, Will F.] Sandia Natl Labs, Combust Res Facil, Livermore, CA USA. RP Colban, WF (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA USA. OI thole, karen/0000-0003-0795-8724 NR 13 TC 0 Z9 0 U1 0 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4314-7 PY 2008 BP 65 EP 79 PG 15 WC Engineering, Aerospace; Engineering, Mechanical; Transportation Science & Technology SC Engineering; Transportation GA BIT71 UT WOS:000262638400007 ER PT B AU McLerran, L AF McLerran, Larry BE Peloso, M TI Quarkyonic Matter and the Phase Diagram of QCD SO PROCEEDINGS OF THE CONFERENCE ON CONTINUOUS ADVANCES IN QCD 2008 LA English DT Proceedings Paper CT 8th Workshop on Continuous Advances in QCD 2008 CY MAY 15-18, 2008 CL Univ Minnesota, William I Fine Theoret Phys Inst, Minneapolis, MN HO Univ Minnesota, William I Fine Theoret Phys Inst ID SKYRME MODEL; SYMMETRY; DENSITY AB Quarkyonic matter is a new phase of QCD at finite temperature and density which is distinct from the confined and de-confined phases. Its existence is unambiguously argued in the large numbers of colors limit, N-c -> infinity, of QCD. Hints of its existence for QCD, N-c = 3, are shown in lattice Monte-Carlo data and in heavy ion experiments. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP McLerran, L (reprint author), Brookhaven Natl Lab, Dept Phys, Bldg 510A, Upton, NY 11973 USA. NR 29 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE BN 978-981-283-865-0 PY 2008 BP 125 EP 134 PG 10 WC Physics, Applied SC Physics GA BIZ16 UT WOS:000263875400011 ER PT B AU Vatsavai, RR Shekhar, S Burk, TE Bhaduri, B AF Vatsavai, Ranga Raju Shekhar, Shashi Burk, Thomas E. Bhaduri, Budhendra BE Latifi, S TI star Miner: A suit of classifiers for spatial, temporal, ancillary, and remote sensing data mining SO PROCEEDINGS OF THE FIFTH INTERNATIONAL CONFERENCE ON INFORMATION TECHNOLOGY: NEW GENERATIONS LA English DT Proceedings Paper CT 5th International Conference on Information Technology - New Generations CY APR 07-09, 2008 CL Las Vegas, NV SP IEEE Comp Soc ID CLASSIFICATION AB Thematic classification of multi-spectral remotely sensed imagery for large geographic regions requires complex algorithms and feature selection techniques. Traditional statistical classifiers rely exclusively on spectral characteristics, but thematic classes are often spectrally overlapping. The spectral response distributions of thematic classes are dependent on many factors including terrain, slope, aspect, soil type, and atmospheric conditions present during the image acquisition. With the availability of geo-spatial databases, it is possible to exploit the knowledge derived from these ancillary geo-spatial databases to improve the classification accuracies. However it is not easy to incorporate this additional knowledge into traditional statistical classification methods. On the other hand, knowledge-based and neural network classifiers can readily incorporate these spatial databases, but these systems are often complex to train and their accuracy is only slightly better than statistical classifiers. In this paper we present a new suit of classifiers developed through NASA funding, which addresses many of these problems and provide a framework for mining multi-spectral and temporal remote sensing images guided by geo-spatial databases. C1 [Vatsavai, Ranga Raju; Bhaduri, Budhendra] Oak Ridge Natl Lab, Computat Sci & Engn Div, Bldg 5600 MS-6017,1 Bethel Valley Rd, Oak Ridge, TN 37831 USA. [Shekhar, Shashi] Univ Minnesota, Dept Comp Sci & Engn, Minneapolis, MN 55455 USA. RP Vatsavai, RR (reprint author), Oak Ridge Natl Lab, Computat Sci & Engn Div, Bldg 5600 MS-6017,1 Bethel Valley Rd, Oak Ridge, TN 37831 USA. EM vatsavairr@ornl.gov; shekhar@cs.umn.edu; teb@mallit.fr.umn.edu; bhaduribl@ornl.gov FU NASA [NCC 5316]; University of Minnesota Agriculture Experiment Station [MIN-42-044]; Army High Performance Computing Research Center under the auspices of Department of the Army, Army Research Laboratory [DAAH04-95-2-0003, DAAH04-95-C-0008] FX This research has been supported through cooperative agreement with NASA (NCC 5316) and by the University of Minnesota Agriculture Experiment Station project MIN-42-044. Support in part is provided by the Army High Performance Computing Research Center under the auspices of Department of the Army, Army Research Laboratory Cooperative agreement number DAAH04-95-2-0003/contract number DAAH04-95-C-0008. NR 20 TC 0 Z9 0 U1 0 U2 3 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3099-4 PY 2008 BP 801 EP + DI 10.1109/ITNG.2008.243 PG 2 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BHQ97 UT WOS:000255578800136 ER PT B AU Roach, D Yepez, S Rackow, K DeLong, T AF Roach, D. Yepez, S. Rackow, K. DeLong, T. BE Uhl, T Ostachowicz, W HolnickiSzulc, J TI Development of a Leave-in-Place Eddy Current Sensor for Remote, Real-Time Detection of Surface and Subsurface Fatigue Cracks SO PROCEEDINGS OF THE FOURTH EUROPEAN WORKSHOP ON STRUCTURAL HEALTH MONITORING 2008 SE Structural Health Monitoring (SHM) LA English DT Proceedings Paper CT 4th European Workshop on Structural Health Monitoring CY JUL 02-04, 2008 CL Cracow, POLAND SP Univ Sci & Technol, Polish Acad Sci, Inst Fundamental Technol Res, PAS, Inst Fluid Flow Machinery, European Off Aerosp Res & Dev, Innowacja Polska Sp z o o AB Health monitoring of structures is a growing concern of the engineering community. This need is even more intense in the case of aging aerospace and civil structures many of which are operating well beyond their initial design lives. An unavoidable by-product of a metallic structure's use is the development of fatigue cracks that degrade integrity. Significant cost barriers to replace these structures have created an aging infrastructure. These economic realities, coupled with an explosion in infrastructure development and unexpected phenomena that have accelerated decay, have produced even greater demands for in-situ structural health monitoring (SHM). Towards that end, innovative sensor designs and deployment methods must be employed to overcome a myriad of inspection impediments stemming from accessibility limitations, complex geometries, and the location and depth of hidden damage. Prevention of unexpected flaw growth and structural failure could be improved if on-board health monitoring systems are used to continuously assess structural integrity. Eddy current (EC) sensing is an effective, low-cost, low-complexity method to detect flaws in structures. However, existing commercial EC equipment is not able to support extensive, remote, field operation for SHM. This paper presents an EC impedance analysis sensor that has been designed to work with low-profile, planar coils to detect cracks in metallic or other conductive structures. By incorporating the planar coils into flexible circuit boards, it was possible to develop a sensor system that is capable of inspecting a large lateral area with sufficient power to detect surface or deeply embedded cracks. The use of a rectangular planar coil, collocated with miniaturized signal processing, conditioning, and wireless communication electronics provides a stand-alone system to perform high-quality, remote, in-situ, real-time, structural health monitoring. Automated inspections of bridges, ships, railcars, and pipelines can be performed over a period of many months without any direct human interaction. Use of this sensor and data acquisition system can yield significant inspection labor savings without sacrificing fidelity, while providing relevant data to determine a structure's integrity. Furthermore, the remote operation and data logging capabilities allow for more frequent structural interrogation. This sensor overcomes a myriad of typical inspection impediments including "lift-off" from the structure being inspected, the presence of non-conductive or conductive barriers on the surface, and the need to conform to uneven surfaces or other complex geometry. A comprehensive performance assessment program will be presented to demonstrate the potential use of this EC sensor system in a wide array of SHM applications. Test results will clearly quantify its ability to detect small fatigue cracks via in-situ, remote operation and highlight its use in guiding condition-based maintenance activities. C1 [Roach, D.; Yepez, S.; Rackow, K.; DeLong, T.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Roach, D (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 0 Z9 0 U1 1 U2 4 PU DESTECH PUBLICATIONS, INC PI LANCASTER PA 439 DUKE STREET, LANCASTER, PA 17602-4967 USA BN 978-1-932078-94-7 J9 STRUCT HLTH MONIT PY 2008 BP 570 EP 578 PG 9 WC Engineering, Aerospace; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BIP22 UT WOS:000261515600067 ER PT B AU Farinholt, KM Overly, TG Taylor, SG Park, G Farrar, CR AF Farinholt, K. M. Overly, T. G. Taylor, S. G. Park, G. Farrar, C. R. BE Uhl, T Ostachowicz, W HolnickiSzulc, J TI New Generation of Impedance-based Wireless Active-Sensor Nodes SO PROCEEDINGS OF THE FOURTH EUROPEAN WORKSHOP ON STRUCTURAL HEALTH MONITORING 2008 SE Structural Health Monitoring (SHM) LA English DT Proceedings Paper CT 4th European Workshop on Structural Health Monitoring CY JUL 02-04, 2008 CL Cracow, POLAND SP Univ Sci & Technol, Polish Acad Sci, Inst Fundamental Technol Res, PAS, Inst Fluid Flow Machinery, European Off Aerosp Res & Dev, Innowacja Polska Sp z o o ID SENSING UNIT AB This paper describes the development of the new generation of an extremely compact, wireless impedance sensor node for use in structural health monitoring (SHM). The sensor node uses a low-cost integrated circuit that can measure and record the electric impedance of a piezoelectric active-sensor. The sensor node also integrates several components, including a microcontroller for local computing, telemetry for wireless data transmission, multiplexers for managing up to seven piezoelectric transducers per node, energy storage mediums, and several triggering options including a wireless triggering circuit into one package to truly realize a comprehensive, self-contained wireless active-sensor node for SHM applications. It is estimated that this sensor node requires less than 50 mW of total power to operate measurement, computation and data transmission. In addition, the sensor node can also be used for the active-sensor self-diagnostic process that can monitor the operational condition of piezoelectric transducers used in SHM applications. The performance of this miniaturized and portable device is compared to our previous results and its broader capabilities are demonstrated. C1 [Farinholt, K. M.; Overly, T. G.; Taylor, S. G.; Park, G.; Farrar, C. R.] Los Alamos Natl Lab, Engn Inst MS T001, Los Alamos, NM 87545 USA. RP Farinholt, KM (reprint author), Los Alamos Natl Lab, Engn Inst MS T001, POB 1663, Los Alamos, NM 87545 USA. RI Farrar, Charles/C-6954-2012; Taylor, Stuart/B-1347-2013 NR 13 TC 0 Z9 0 U1 0 U2 1 PU DESTECH PUBLICATIONS, INC PI LANCASTER PA 439 DUKE STREET, LANCASTER, PA 17602-4967 USA BN 978-1-932078-94-7 J9 STRUCT HLTH MONIT PY 2008 BP 590 EP 597 PG 8 WC Engineering, Aerospace; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BIP22 UT WOS:000261515600069 ER PT B AU Vahala, G Yepez, J Soe, M Vahala, L Carter, J Ziegeler, S AF Vahala, G. Yepez, Jeffrey Soe, Min Vahala, Linda Carter, Jonathan Ziegeler, Sean TI MHD Turbulence Studies Using Lattice Boltzmann Algorithms-Physical Simulations Using 9,000 Cores on the Air Force Research Laboratory HAWK Supercomputer SO PROCEEDINGS OF THE HPCMP USERS GROUP CONFERENCE 2008 LA English DT Proceedings Paper CT Conference on High Performance Computer Modernization Program CY JUL 14-17, 2008 CL Seattle, WA DE turbulence; lattice Boltzmann; magnetohydrodynamics AB Most non-spectral computational fluid dynamics (CFD) algorithms do not scale to many thousands of cores. Here, we examine a particular mesoscopic representation of free decaying magnetohydrodynamics (MHD) turbulence that is amenable to massive parallelization to the full 9,000 cores available on Air Force Research Laboratory (AFRL) SGI Altix 4700 (Hawk). Moreover, our mesoscopic lattice Boltzmann (LB) algorithm will automatically enforce the important del.B=0 constraint without any need for magnetic field divergence cleaning. Isosurfaces of vorticity and current for LB simulations on a spatial grid of 18003 show the long time existence of large scale magnetic and velocity structures. This is in stark contrast to the long time behavior of the velocity isosurfaces which all disintegrate into small scale structures. C1 [Vahala, G.] Coll William & Mary, Dept Phys, Williamsburg, VA 23185 USA. [Yepez, Jeffrey] A F Res Lab AFRL, Bedford, MA 01731 USA. [Soe, Min] Rogers State Univ, Dept Math & Phys, Claremore, OK 74017 USA. [Vahala, Linda] Old Dominion Univ, Norfolk, VA 23529 USA. [Carter, Jonathan] NERSC Div, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Ziegeler, Sean] US Naval Res Lab NRL SSC, Stennis Space Ctr, Washington, MS 20375 USA. RP Vahala, G (reprint author), Coll William & Mary, Dept Phys, Williamsburg, VA 23185 USA. EM gvahala@gmail.com; jefftey.yepez@gmail.com; msoe.rsu@gmail.com; lvahala@odu.edu; jtcarter@lbl.gov; seanzig@nrlssc.navy.mil FU Department of Energy; Air Force Office of Scientific Research; AFRL FX The authors were supported by grants from Department of Energy, Air Force Office of Scientific Research, and AFRL. The simulation results were obtained under the Capability Applications Project program on the Department of Defense Major Shared Resource Centers at the Air Force Research Laboratory. NR 4 TC 0 Z9 0 U1 0 U2 5 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3515-9 PY 2008 BP 138 EP + DI 10.1109/DoD.HPCMP.UGC.2008.32 PG 3 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Physics, Applied SC Computer Science; Engineering; Physics GA BJC07 UT WOS:000264661200020 ER PT B AU Andzelm, J Rawlett, A Dougherty, J Govind, N Baer, R AF Andzelm, Jan Rawlett, Adam Dougherty, Joseph Govind, Niranjan Baer, Roi TI Performance of DFT Methods in the Calculation of Optical Spectra of Chromophores SO PROCEEDINGS OF THE HPCMP USERS GROUP CONFERENCE 2008 LA English DT Proceedings Paper CT Conference on High Performance Computer Modernization Program CY JUL 14-17, 2008 CL Seattle, WA ID DENSITY-FUNCTIONAL THEORY; GENERALIZED-GRADIENT-APPROXIMATION; GUEST-HOST; ABSORPTION; MOLECULES AB We present electronic structure calculations on the ultraviolet/visible (UV-Vis) spectra of highly active push-pull chromophores. In particular, we have implemented and applied the recently developed long-range corrected Baer-Neuhauser-Livshits (BNL) exchange-correlation,functional. We have implemented this functional in the NWChem program package. The UV-Vis spectra obtained with the BNL functional are found to be superior compared with other density functional theory (DFT) functionals. The method captures the charge-transfer states particularly well while the pi-pi* excitations are less accurate. Consideration of the chromophore conformations also improves the strength of the pi-pi* excitations. C1 [Andzelm, Jan; Rawlett, Adam; Dougherty, Joseph] US Army Res Lab, Weapons & Mat Directorate, Aberdeen Proving Ground, MD USA. [Govind, Niranjan] Pacific Northwest Natl Lab, Sci Lab, Richland, WA USA. [Baer, Roi] Hebrew Univ Jerusalem, Fritz Haber Ctr Molecular Dynam, Inst Chem, Jerusalem 91904, Israel. RP Andzelm, J (reprint author), US Army Res Lab, Weapons & Mat Directorate, Aberdeen Proving Ground, MD USA. EM jandzelm@arl.army.mil; niri.govind@pnl.gov; roi.baer@huji.ac.il RI Govind, Niranjan/D-1368-2011 FU US Department of Energy [DE-AC06-76RLO 1830]; Office of Biological and Environmental Research; EMSL operations FX The work at the Pacific Northwest National Laboratory (PNNL) was supported by the US Department of Energy under Contract DE-AC06-76RLO 1830 (Office of Biological and Environmental Research, EMSL operations). The Pacific Northwest National Laboratory is operated by the Battelle Memorial Institute. The authors are indebted to Geoffrey A. Lindsay, Andrew Chafin, Andrew G. Mott, Robert C. Hoffman, and Timothy M. Pritchett for intellectual discussions and insight into this research. NR 28 TC 1 Z9 1 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3515-9 PY 2008 BP 235 EP + DI 10.1109/DoD.HPCMP.UGC.2008.80 PG 3 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Physics, Applied SC Computer Science; Engineering; Physics GA BJC07 UT WOS:000264661200036 ER PT B AU Boatz, JA Sorescu, D AF Boatz, Jerry A. Sorescu, Dan TI Polynitrogen/Nanoaluminum Surface Interactions SO PROCEEDINGS OF THE HPCMP USERS GROUP CONFERENCE 2008 LA English DT Proceedings Paper CT Conference on High Performance Computer Modernization Program CY JUL 14-17, 2008 CL Seattle, WA ID MOLECULAR-ORBITAL METHODS; TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; APPROXIMATION; EXCHANGE; POINTS; METALS AB First-principles density functional theory (LIFT) calculations using the generalized gradient approximation (GGA) have been performed to study the adsorption of a series of all-nitrogen and high-nitrogen compounds of increasing sizes and complexity on the Al(111) surface. The calculations employ periodic slab models with 4 Al layers, ranging in size from (3 x 3) to (5x5) surface unit cells, and containing up to 144 Al atoms. Complementary quantum chemical calculations, utilizing DFT and second-order perturbation theory methods, of the ground state potential energy surfaces of the corresponding polynitrogen/high nitrogen species in the absence of the aluminum surface also have been performed. The initial set of studies performed in the first year of this challenge project, which focused on the adsorption and reaction properties of N-x (x=1-5), NHx (x=1-3), N2Hx (x=1-4), N3H, N3H3, and N4H4 species on Al(111), have been extended to include larger polynitrogen systems such as N-6, N-8, N-10, and N-12. The C48N12 fullerene-like molecule way included in this series in place of N-60, which was found to be unstable in the gas phase. Furthermore,, simple nitrogen-containing heterocycles such as furazan (C2N2H2O), 2H-1,2,3- and 4H-1,2,4-triazole (C2N3H3), and 1H- and 2H-tetrazole (CN4H2) have been studied. Additional compounds of interest include the monosubstituted di(cyclopropyl)triazole (C11N6H12) and di(cyclobutyl)triazole (C13N5H16) derivatives of triazene. For these systems, surface interaction mechanisms involving both dissociative and nondissociative processes have been characterized as a function of molecular orientation and surface site. The dissociative mechanisms generally include elimination of one or more N-2 molecules. C1 [Boatz, Jerry A.] USAF, Res Lab, Prop Directorate, Space Missile Prop Div,RZS, Edwards Afb, CA USA. [Sorescu, Dan] US DOE, Natl Energy Technol Lab, Pittsburgh, PA USA. RP Boatz, JA (reprint author), USAF, Res Lab, Prop Directorate, Space Missile Prop Div,RZS, Edwards Afb, CA USA. EM jerry.boatz@edwards.af.mil; dan.sorescu@netl.doe.gov FU DoD High Performance Computing Modernization Program FX The authors gratefully acknowledge grants of computer time at the Air Force Research Laboratory, US Army Engineer Research and Development Center, and the Navy DoD Supercomputing Resource Centers (DSRCs), sponsored by the DoD High Performance Computing Modernization Program. NR 21 TC 0 Z9 0 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3515-9 PY 2008 BP 247 EP + DI 10.1109/DoD.HPCMP.UGC.2008.58 PG 3 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Physics, Applied SC Computer Science; Engineering; Physics GA BJC07 UT WOS:000264661200038 ER PT B AU Cole, EI AF Cole, Edward I., Jr. GP IEEE TI Non-Destructive IC Defect Localization Using Optical Beam-Based Imaging SO PROCEEDINGS OF THE IEEE 2008 CUSTOM INTEGRATED CIRCUITS CONFERENCE SE IEEE Custom Integrated Circuits Conference LA English DT Proceedings Paper CT IEEE Custom Integrated Circuits Conference CY SEP 21-24, 2008 CL San Jose, CA SP IEEE, IEEE Custom Integrated Circuits Conf, IEEE Solid State Circuits Soc, IEEE Elect Devices Soc AB Optical beam failure analysis methods provide unique capabilities to identify and localize defect types that would be difficult or impossible by other methods. By understanding the physics of signal generation, the user gains the insight necessary to optimize technique performance. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cole, EI (reprint author), Sandia Natl Labs, MS 1072,1515 Eubank SE, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 978-1-4244-2018-6 J9 IEEE CUST INTEGR CIR PY 2008 BP 53 EP 56 DI 10.1109/CICC.2008.4672018 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BIT75 UT WOS:000262643900012 ER PT B AU Heroux, M Wen, ZF Wu, JF Xu, YS AF Heroux, Mike Wen, Zhaofang Wu, Junfeng Xu, Yuesheng BE Tudruj, M TI Initial Experiences with the BEC Parallel Programming Environment SO PROCEEDINGS OF THE INTERNATIONAL SYMPOSIUM ON PARALLEL AND DISTRIBUTED COMPUTING LA English DT Proceedings Paper CT 7th International Symposium on Parallel and Distributed Computing CY JUL 01-05, 2008 CL Cracow, POLAND SP Polish Acad Sci, Inst Comp Sci, Polish Japanese Inst Informat Technol, AGH Univ Sci & Technol, Fac Elect Engn, Automat Comp Sci & Elect AB Bundle-Exchange-Compute (BEC) is a new virtual shared memory parallel programming environment for distributed-memory machines. Different from and complementary to other Global Address Space (GAS) programming model research efforts, BEC has built-in efficient support for unstructured applications that inherently require high-volume random fine-grained communication, such as parallel graph algorithms, sparse-matrices, and large-scale physics simulations. In BEC, the global view of shared data structures enables ease of algorithm design and programming; and for good application performance, fine-grained (random) accesses to shared data are automatically and dynamically bundled together for coarse-grained message-passing. BEC frees the users from explicit management of data distribution, locality, and communication. Therefore, BEC is much easier to program than MPI, while achieving comparable application performance. This paper presents some initial BEC applications, which show that simple BEC programs can match very complex and highly optimized MPI codes. C1 [Heroux, Mike; Wen, Zhaofang] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Wu, Junfeng; Xu, Yuesheng] Syracuse Univ, Syracuse, NY 13244 USA. RP Heroux, M (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM maherou@sandia.gov; zwen@sandia.gov; juwu@syr.edu; yxu06@syr.edu OI Heroux, Michael/0000-0002-5893-0273 FU Sandia National Laboratories, Albuquerque, New Mexico [87185]; Livermore, California [94550]; United States Department of Energy's National Nuclear Security Administration [DE-AC04-94-AL85000]; Office of Science of the U.S. Department of Energy [DE-AC03-76SF00098] FX This research was sponsored by Sandia National Laboratories, Albuquerque, New Mexico 87185 and Livermore, California 94550. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energys National Nuclear Security Administration under Contract DE-AC04-94-AL85000.; This research used resources of the National Energy Research Scientific Computing Center at Lawrence Berkeley National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098. NR 13 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3472-5 PY 2008 BP 205 EP + DI 10.1109/ISPDC.2008.31 PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIV30 UT WOS:000263137300027 ER PT B AU Phuoc, TX Soong, Y Chyu, MK AF Phuoc, Tran X. Soong, Yee Chyu, Minking K. GP ASME TI Nanofluid generation using multi-beam laser ablation technique SO PROCEEDINGS OF THE MICRO/NANOSCALE HEAT TRANSFER INTERNATIONAL CONFERENCE 2008, PTS A AND B LA English DT Proceedings Paper CT 1st ASME Micro/Nanoscale Heat Transfer International Conference CY JAN 06-09, 2008 CL Natl Cheng Kung Univ, Tainan, TAIWAN SP ASME, Nanotechnol Inst, ASME, Heat Transfer Div HO Natl Cheng Kung Univ ID NANOPARTICLES; COLLOIDS; ENHANCEMENT; LIQUIDS AB Multi-beam laser ablation in liquid was used to synthesize nanofluids of silver, Zinc, and aluminum in liquids. In our experiments, two single-mode, Q-switched Nd-Yag lasers operating at 1064 nm, pulse duration of 5.5 ns and 10 Hz rep rate were used. Our results have shown that both laser intensities and multi-beam ablation can increase the ablation rate and promote reduction of the particle sizes and particle size distribution. For silver, we have generated various samples of nanofluids with particles of sizes mainly in the range of 20 to 30 nm. These samples were stable for several months without the need of using dispersants or surfactants. However, for aluminum, the generated fluids were not stable and significant amount of solid precipitates were observed in the stock solutions. The size distribution was from about 5 nm to 300 nm indicating that the particle agglomerated and large distribution in sizes. Typical results from TEM analysis indicated that, for silver-water nanofluids, Ag nanoparticles were fcc single crystals. For aluminum, the particles had different shapes and sizes. These shapes were triangular, rectangular, and fibrous. C1 [Phuoc, Tran X.; Soong, Yee] Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. RP Phuoc, TX (reprint author), Natl Energy Technol Lab, POB 10940,MS 84-340, Pittsburgh, PA 15236 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4292-8 PY 2008 BP 615 EP 621 PG 7 WC Engineering, Mechanical; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA BHQ35 UT WOS:000255392000087 ER PT B AU Masters, ND Ye, WJ AF Masters, Nathan D. Ye, Wenjing GP ASME TI Multiscale modeling of heat transfer in a thermal sensing atomic force microscope SO PROCEEDINGS OF THE MICRO/NANOSCALE HEAT TRANSFER INTERNATIONAL CONFERENCE 2008, PTS A AND B LA English DT Proceedings Paper CT 1st ASME Micro/Nanoscale Heat Transfer International Conference CY JAN 06-09, 2008 CL Natl Cheng Kung Univ, Tainan, TAIWAN SP ASME, Nanotechnol Inst, ASME, Heat Transfer Div HO Natl Cheng Kung Univ DE multiscale modeling; microscale heat transfer; information preserving DSMC; thermal sensing atomic force microscopy AB Thermal Sensing Atomic Force Microscope (TSAFM) systems utilize heat transfer in continuum and low-speed rarefied gas flow regimes to perform topological surface scans. Spanning flow regimes complicates the modeling required to analyze scan data. In this paper we present a hybrid Octant Flux Splitting IP-DSMC/BEM model of the steady state heat transfer from a TSFAM cantilever and compare with the uncorrected continuum solution as well as a macro model developed for this problem. C1 [Masters, Nathan D.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Masters, ND (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4292-8 PY 2008 BP 1375 EP 1376 PG 2 WC Engineering, Mechanical; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA BHQ35 UT WOS:000255392000188 ER PT S AU Turner, M AF Turner, Manisha BE Oluseyi, HM TI Unveiling the secrets of archimedes SO PROCEEDINGS OF THE NATIONAL SOCIETY OF BLACK PHYSICISTS SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Joint Annual Conference of the 30th Annual Meeting of the National-Society-of-Black-Physicists/4th Meeting of the National-Society-of-Hispanic-Physicists CY FEB 21-24, 2007 CL Boston, MA SP Nat Soc Black Phys, Nat Soc Hispanic Phys AB Progress has been made at the Stanford Linear Accelerator Center (SLAC) toward deciphering the remaining 10-20% of ancient Greek text contained in the Archimedes palimpsest. The text is known to contain valuable works by the mathematician, including the Method of Mechanical Theorems, the Equilibrium of Planes, On Floating Bodies, and several diagrams. The only surviving copy of the text was recycled into a prayer book in the Middle Ages. The ink used to write on the goat skin parchment is partly composed of iron, which is visible by x-ray radiation. To image the palimpsest pages, the parchment was framed and placed in a stage that moved according to the raster method. When an x-ray beam was incident upon the parchment the iron in the ink was detected by a germanium detector. The resultant signal was converted to a gray-scale image. It was extremely important that each line of data was well aligned with the line that came before it. The objectives of this experiment were to determine the best parameters for producing well-aligned images and to reduce the scanning time. Imaging half a page of parchment during previous beam time for this project was achieved in thirty hours. Equations were produced to evaluate count time, shutter time, and the number of pixels in this experiment. On Beamline 6-2 at the Stanford Synchrotron Radiation Laboratory (SSRL), actual scanning time was reduced by one fourth. The remaining pages were successfully imaged and sent to ancient Greek experts for translation. C1 Norfolk State Univ, Off Sci, SULI Program, Stanford Linear Accelerator Ctr, Menlo Pk, CA USA. RP Turner, M (reprint author), Norfolk State Univ, Off Sci, SULI Program, Stanford Linear Accelerator Ctr, Menlo Pk, CA USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0510-3 J9 AIP CONF PROC PY 2008 VL 991 BP 163 EP 170 PG 8 WC Astronomy & Astrophysics; Biophysics; Education, Scientific Disciplines; Physics, Multidisciplinary SC Astronomy & Astrophysics; Biophysics; Education & Educational Research; Physics GA BHM09 UT WOS:000254219500019 ER PT S AU Todd, DS Leitner, D Pint, C Grote, DP AF Todd, D. S. Leitner, D. Pint, C. Grote, D. P. BE Munro, E Rouse, J TI Improving extraction and transport simulations of the superconducting ECR ion source VENUS SO PROCEEDINGS OF THE SEVENTH INTERNATIONAL CONFERENCE ON CHARGED PARTICLE OPTICS (CPO-7) SE Physics Procedia LA English DT Proceedings Paper CT 7th International Conference on Charged Particle Optics (CPO-7) CY JUL 24-28, 2006 CL Trinity Coll, Cambridge, ENGLAND HO Trinity Coll DE Ion sources; Ion beam extraction; Ion beam transport; Particle-in-cell (PIC) codes; Suerconducting ECR sources ID BEAMS; PLASMA AB A plasma sheath extraction model has been added to the three-dimensional, particle-in-cell (PIC) code WARP in order to simulate the extraction and transport of ion beams from the superconducting ECR ion source VENUS. The WARP code is ideally suited to simulate ECR ion source transport systems since it can handle large particle numbers, multiple species, applied and self fields, and has a powerful PYTHON programming shell that allows the user to easily customize the simulation. The addition of an axially symmetric sheath extraction model for a multi species plasma allows for the simulation of the entire VENUS beam line including extraction. To benchmark this model against experiment we have produced axially symmetric beams from VENUS composed almost exclusively of one ion species. These axially symmetric beams are produced by operating the VENUS source without sextupoles, which confine the plasma radially. In addition we performed single species experiments with the sextupoles energized. These measurements confirm the expected triangular shape of the extracted beam. To simulate asymmetric plasma extraction, a simple approximation using the results of the symmetric extraction model is employed. Comparisons between simulation and experiment for both extraction cases at a beam profile diagnostic device (beam harp) after the extraction and at an emittance scanner after the analyzing magnet are presented. Good agreement in both the size and shape of the beam were found at the beam harp provided the beam is not over-focused to a waist before the harp. Simulation and experiment also show reasonable agreement in beam size and divergence angle when comparing emittance scanner measurements after the analyzing dipole. (C) 2008 Elsevier B. V. All rights reserved. C1 [Todd, D. S.; Leitner, D.; Pint, C.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Grote, D. P.] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Todd, DS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM dstodd@lbl.gov FU U.S. Department of Energy [DE AC03-76SF00098] FX This work was supported by the Director, Office of High Energy and Nuclear Physics, Nuclear Physics Division of the U.S. Department of Energy under Contract No. DE AC03-76SF00098. NR 13 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1875-3892 J9 PHYSCS PROC PY 2008 VL 1 IS 1 BP 265 EP 272 DI 10.1016/j.phpro.2008.07.105 PG 8 WC Physics, Particles & Fields SC Physics GA BNZ08 UT WOS:000275907500033 ER PT S AU Veryovkin, IV Tripa, CE Pellin, MJ AF Veryovkin, Igor V. Tripa, C. Emil Pellin, Michael J. BE Munro, E Rouse, J TI Efficient multiple beam ion optics for quantitative surface analysis: from simulations to a fully operational instrument SO PROCEEDINGS OF THE SEVENTH INTERNATIONAL CONFERENCE ON CHARGED PARTICLE OPTICS (CPO-7) SE Physics Procedia LA English DT Proceedings Paper CT 7th International Conference on Charged Particle Optics (CPO-7) CY JUL 24-28, 2006 CL Trinity Coll, Cambridge, ENGLAND HO Trinity Coll DE Sputtering; Photoionization of atoms; Secondary-ion mass spectrometry (SIMS); Ion optics; Time-of-flight mass spectrometry ID NEUTRAL MASS-SPECTROMETRY; PEPTIDES; LASER; IONIZATION; POSTIONIZATION; DESORPTION; SPECTRA; MISSION; RETURN AB A new ion optics system was developed and experimentally tested, which allows for high-resolution multiple beam characterization of materials. This system enables: (1) efficient, quasi-simultaneous measurements of the mass spectra of laser post-ionized sputtered species and secondary ions as well as secondary electron imaging, that can be accompanied and assisted by (2) low energy ion milling and (3) in-situ optical imaging and laser desorption with submicron resolution. Altogether, this ion optics system provides a versatile, sensitive combination of an analytical mass spectrometer and ion, electron and optical microscopes, which can efficiently detect one out of four sample atoms consumed during the analysis. (C) 2008 Elsevier B. V. All rights reserved C1 [Veryovkin, Igor V.; Tripa, C. Emil; Pellin, Michael J.] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Veryovkin, IV (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave,Bldg 200, Argonne, IL 60439 USA. EM verigo@anl.gov RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 22 TC 11 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1875-3892 J9 PHYSCS PROC PY 2008 VL 1 IS 1 BP 379 EP 389 DI 10.1016/j.phpro.2008.07.119 PG 11 WC Physics, Particles & Fields SC Physics GA BNZ08 UT WOS:000275907500045 ER PT S AU Lebedev, G Jozwiak, C Andresen, N Lanzara, A Hussain, Z AF Lebedev, G. Jozwiak, C. Andresen, N. Lanzara, A. Hussain, Z. BE Munro, E Rouse, J TI TOF electron energy analyzer for spin and angular resolved photoemission spectroscopy SO PROCEEDINGS OF THE SEVENTH INTERNATIONAL CONFERENCE ON CHARGED PARTICLE OPTICS (CPO-7) SE Physics Procedia LA English DT Proceedings Paper CT 7th International Conference on Charged Particle Optics (CPO-7) CY JUL 24-28, 2006 CL Trinity Coll, Cambridge, ENGLAND HO Trinity Coll DE TOF; photoemission spectroscopy; energy analyser ID RESOLUTION AB Current pulsed laser and synchrotron x-ray sources provide new opportunities for Time-Of-Flight (TOF) based photoemission spectroscopy to increase photoelectron energy resolution and efficiency compared to current standard techniques. The principals of photoelectron timing front formation, temporal aberration minimization, and optimization of electron beam transmission are presented. We have developed these concepts into a high resolution Electron Optical Scheme (EOS) of a TOF Electron Energy Analyzer (TOF-EEA) for photoemission spectroscopy. The EOS of the analyzer includes an electrostatic objective lens, three columns of transport lenses and a 90 degree energy band pass filter (BPF). The analyzer has two modes of operation: Spectrometer Mode (SM) with straight passage of electrons through the EOS undeflected by the BPF, allowing the entire spectrum to be measured, and Monochromator Mode (MM) in which the BPF defines a certain energy window inside the scope of the electron energy spectrum. (C) 2008 Elsevier B. V. All rights reserved. C1 [Lebedev, G.; Jozwiak, C.; Andresen, N.; Lanzara, A.; Hussain, Z.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lebedev, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd MS 7-222, Berkeley, CA 94720 USA. EM gvlebedev@lbl.gov NR 6 TC 2 Z9 2 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1875-3892 J9 PHYSCS PROC PY 2008 VL 1 IS 1 BP 413 EP 423 DI 10.1016/j.phpro.2008.07.122 PG 11 WC Physics, Particles & Fields SC Physics GA BNZ08 UT WOS:000275907500048 ER PT B AU DuBois, D DuBois, A Connor, C Poole, S AF DuBois, David DuBois, Andrew Connor, Carolyn Poole, Steve BE Pocek, KL Buell, D TI Sparse Matrix-Vector Multiplication on a Reconfigurable Supercomputer SO PROCEEDINGS OF THE SIXTEENTH IEEE SYMPOSIUM ON FIELD-PROGRAMMABLE CUSTOM COMPUTING MACHINES SE Annual IEEE Symposium on Field-Programmable Custom Computing Machines LA English DT Proceedings Paper CT 16th Annual IEEE Symposium on Field-Programmable Custom Computing Machines CY APR 14-15, 2008 CL Stanford, CA SP IEEE Comp Soc TCCA DE FPGA; Sparse Matrix-Vector Multiplication; Reconfigurable hardware; Iterative methods AB Double precision floating point Sparse Matrix-Vector Multiplication (SMVM) is a critical computational kernel used in iterative solvers for systems of spare linear equations. The poor data locality exhibited by sparse matrices along with the high memory bandwith requirements of SMVM result in poor performance on general purpose processors. Field Programmable Gate Arrays (FPGAs) offer a possible alternative with their customizable and application-targeted memory sub-system and processing elements. C1 [DuBois, David; DuBois, Andrew; Connor, Carolyn] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Poole, Steve] Oak Ridge Natl Lab, Oak Ridge, TN USA. RP DuBois, D (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM dhd@lanl.gov; ajd@lanl.gov; connor@lanl.gov; spoole@ornl.gov RI Connor, Carolyn/F-1262-2011 FU US Department of Energy [DE-AC52-06NA25396]; Los Alamos National Laboratory; [LAUR-08-1645] FX Los Alamos National Laboratory, an affirmative action/equal opportunity employer, is operated by the Los Alamos National Security, LLC for the National Nuclear Security Administration of the U.S. Department of Energy under contract DE-AC52-06NA25396. By acceptance of this article, the publisher recognizes that the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, or to allow others to do so, for U.S. Government purposes. Los Alamos National Laboratory requests that the publisher identify this article as work performed under the auspices of the U.S. Department of Energy. Los Alamos National Laboratory strongly supports academic freedom and a researchers right to publish; as an institution, however, the Laboratory does not endorse the viewpoint of a publication or guarantee its technical correctness. This paper is published under LAUR-08-1645. NR 12 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3307-0 J9 ANN IEEE SYM FIELD P PY 2008 BP 239 EP + DI 10.1109/FCCM.2008.53 PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BJB25 UT WOS:000264409100023 ER PT B AU DuBois, D DuBois, A Boorman, T Connor, C Poole, S AF DuBois, David DuBois, Andrew Boorman, Thomas Connor, Carolyn Poole, Steve BE Pocek, KL Buell, D TI An Implementation of the Conjugate Gradient Algorithm on FPGAs SO PROCEEDINGS OF THE SIXTEENTH IEEE SYMPOSIUM ON FIELD-PROGRAMMABLE CUSTOM COMPUTING MACHINES SE Annual IEEE Symposium on Field-Programmable Custom Computing Machines LA English DT Proceedings Paper CT 16th Annual IEEE Symposium on Field-Programmable Custom Computing Machines CY APR 14-15, 2008 CL Stanford, CA SP IEEE Comp Soc TCCA AB The conjugate gradient is a prominent iterative method for solving systems of sparse linear equations. Large-scale scientific applications often utilize a conjugate gradient solver at their computational core. Since a single iteration of a conjugate gradient solver requires a sparse matrix-vector multiply operation it is imperative that this operation be computed efficiently. In this paper we present a field programmable gate array (FPGA) based implementation of a double precision, non-preconditioned, conjugate gradient solver for finite-element or finite-difference methods. We show that our FPGA implementation can outperform current generation processors while running at a similar to 30X slower clock rate. Our work utilizes the SRC Computers, Inc. MAPStation hardware platform along with the "Carte" software programming environment. C1 [DuBois, David; DuBois, Andrew; Boorman, Thomas; Connor, Carolyn] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Poole, Steve] Oak Ridge Natl Lab, Oak Ridge, TN USA. RP DuBois, D (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM dhd@lanl.gov; ajd@lanl.gov; tmb@lanl.gov; connor@lanl.gov; spoole@ornl.gov RI Connor, Carolyn/F-1262-2011 NR 4 TC 4 Z9 4 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3307-0 J9 ANN IEEE SYM FIELD P PY 2008 BP 296 EP + DI 10.1109/FCCM.2008.54 PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BJB25 UT WOS:000264409100040 ER PT B AU Kastengren, AL Powell, CF Im, KS Wang, YJ Wang, J AF Kastengren, A. L. Powell, C. F. Im, K. -S. Wang, Y. -J. Wang, J. GP ASME TI Measurement of biodiesel blend and conventional diesel spray structure using X-ray radiography SO PROCEEDINGS OF THE SPRING TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT ASME Internal Combustion Engine Division Sprint Technical Conference CY APR 27-30, 2008 CL Chicago, IL SP ASME, Internal Combust Engine Div AB The near-nozzle structure of several non-evaporating biodiesel blend sprays has been studied using x-ray radiography. Radiography allows quantitative measurements of the fuel distribution in sprays to be made with high temporal and spatial resolution. Measurements have been made at different values of injection pressure, ambient density, and with two different nozzle geometries to understand the influences of these parameters on the spray structure of the biodiesel blend. These measurements have been compared to corresponding measurements of Viscor, a diesel calibration fluid, to demonstrate the fuel effects on the spray structure. Generally, the biodiesel blend spray has a similar structure to the spray of Viscor. For the nonhydroground nozzle used in this study, the biodiesel blend spray has a slightly slower penetration into the ambient gas than the Viscor spray. The cone angle of the biodiesel blend spray is generally smaller than that of the Viscor spray, indicating that the biodiesel blend spray is denser than the Viscor spray. For the hydroground nozzle, both fuels produce sprays with initially wide cone angles that transition to narrow sprays during the steady-state portion of the injection event. These variations in cone angle with time are timed later for the biodiesel blend spray than for the Viscor spray, indicating that the dynamics of the injector needle as it opens are somewhat different for the two fuels. C1 [Kastengren, A. L.; Powell, C. F.] Argonne Natl Lab, Ctr Transportat Res, Argonne, IL 60439 USA. RP Kastengren, AL (reprint author), Argonne Natl Lab, Ctr Transportat Res, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 28 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4813-5 PY 2008 BP 15 EP 27 PG 13 WC Engineering, Mechanical SC Engineering GA BHU76 UT WOS:000256549300002 ER PT B AU Wallner, T Miers, SA McConnell, S AF Wallner, Thomas Miers, Scott A. McConnell, Steve GP ASME TI A comparison of ethanol and butanol as oxygenates using a direct-injection, spark-ignition (DISI) engine SO PROCEEDINGS OF THE SPRING TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT ASME Internal Combustion Engine Division Sprint Technical Conference CY APR 27-30, 2008 CL Chicago, IL SP ASME, Internal Combust Engine Div AB This study was designed to evaluate a 'what-if' scenario in terms of using butanol as an oxygenate, in place of ethanol in an engine calibrated for gasoline operation. No changes to the stock engine calibration were performed for this study. Combustion analysis, efficiency and emissions of pure gasoline, 10 % ethanol and 10 % butanol blends in a modem, direct-injection four-cylinder, spark ignition engine were analyzed. Data was taken at engine speeds of 1000 RPM up to 4000 RPM with load varying from 0 Nm (idle) to 150 Nm. Relatively minor differences existed between the three fuels for the combustion characteristics such as heat release rate, 50 % mass fraction burned, and coefficient of variation of indicated mean effective pressure at low and medium engine loads. However at high engine loads the reduced knock resistance of the butanol blend forced the engine control unit to retard the ignition timing substantially, compared to the gasoline baseline and even more pronounced compared to the ethanol blend. Brake specific volumetric fuel consumption which represented a normalized volumetric fuel flow rate, was lowest for the gasoline baseline fuel, due to the higher energy density. The 10 % butanol blend had a lower volumetric fuel consumption compared to the ethanol blend, as expected based on energy density differences. Results showed little difference in regulated emissions between 10 % ethanol and 10 % butanol. The ethanol blend produced the highest peak specific NO, due to the high octane rating of ethanol and effective anti-knock characteristics. Overall, the ability of butanol to perform equally as well as ethanol from an emissions and combustion standpoint, with a decrease in fuel consumption, initially appears promising. Further experiments are planned to explore the full operating range of the engine and the potential benefits of higher blend ratios of butanol. C1 [Wallner, Thomas; Miers, Scott A.; McConnell, Steve] Argonne Natl Lab, Argonne, IL 60439 USA. RP Wallner, T (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 19 TC 3 Z9 3 U1 1 U2 4 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4813-5 PY 2008 BP 129 EP 139 PG 11 WC Engineering, Mechanical SC Engineering GA BHU76 UT WOS:000256549300013 ER PT B AU Biruduganti, MS Gupta, SB Sekar, R AF Biruduganti, Munidhar S. Gupta, Sreenath B. Sekar, Raj GP ASME TI Low temperature combustion using nitrogen enrichment to mitigate NOx from large bore natural gas-fueled engines SO PROCEEDINGS OF THE SPRING TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT ASME Internal Combustion Engine Division Sprint Technical Conference CY APR 27-30, 2008 CL Chicago, IL SP ASME, Internal Combust Engine Div AB Low Temperature Combustion (LTC) is identified as one of the pathways to meet the mandatory ultra low NOx emissions levels set by regulatory agencies. This phenomenon can be realized by utilizing various advanced combustion control strategies. The present work discusses nitrogen enrichment using an Air Separation Membrane (ASM) as a better alternative to the mature Exhaust Gas Re-circulation (EGR) technique currently in use. A 70% NOx reduction was realized with a moderate 2% nitrogen enrichment while maintaining power density and simultaneously improving Fuel Conversion Efficiency (FCE). The maximum acceptable Nitrogen Enriched Air (NEA) in a single cylinder spark ignited natural gas engine was investigated in this paper. Any enrichment beyond this level degraded engine performance both in terms of power density and FCE, and unburned hydrocarbon (UHC) emissions. The effect of ignition timing was also studied with and without N-2 enrichment. Finally, lean bum versus stoichiometric operation utilizing NEA was compared. Analysis showed that lean bum operation along with NEA is one of the effective pathways for realizing better FCE and lower NOx emissions. C1 [Biruduganti, Munidhar S.; Gupta, Sreenath B.; Sekar, Raj] Argonne Natl Lab, Argonne, IL 60439 USA. RP Biruduganti, MS (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4813-5 PY 2008 BP 367 EP 374 PG 8 WC Engineering, Mechanical SC Engineering GA BHU76 UT WOS:000256549300036 ER PT B AU McIntyre, DL Woodruff, SD McMillian, MH Richardson, SW Gautam, M AF McIntyre, Dustin L. Woodruff, Steven D. McMillian, Michael H. Richardson, Steven W. Gautam, Mridul GP ASME TI Lean-burn stationary natural gas reciprocating engine operation with a prototype miniature diode side pumped passively Q-switched laser spark plug SO PROCEEDINGS OF THE SPRING TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION LA English DT Proceedings Paper CT ASME Internal Combustion Engine Division Spring Technical Conference CY APR 27-30, 2008 CL Chicago, IL SP ASME, Internal Combust Engine Div AB To meet the ignition system needs of large bore lean bum stationary natural gas engines a laser diode side pumped passively Q-switched laser igniter was developed and used to ignite lean mixtures in a single cylinder research engine. The laser design was produced from previous work. The in-cylinder conditions and exhaust emissions produced by the miniaturized laser were compared to that produced by a laboratory scale commercial laser system used in prior engine testing. The miniaturized laser design as well as the combustion and emissions data for both laser systems was compared and discussed. It was determined that the two laser systems produced virtually identical combustion and emissions data. C1 [McIntyre, Dustin L.; Woodruff, Steven D.; McMillian, Michael H.; Richardson, Steven W.] US DOE, Natl Energy Technol Lab, Morgantown, WV 26507 USA. RP McIntyre, DL (reprint author), US DOE, Natl Energy Technol Lab, 3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 17 TC 1 Z9 1 U1 0 U2 3 PU AMER SOC MECHANICAL ENGINEERS PI NEW YORK PA THREE PARK AVENUE, NEW YORK, NY 10016-5990 USA BN 978-0-7918-4813-5 PY 2008 BP 405 EP 413 PG 9 WC Engineering, Mechanical SC Engineering GA BHU76 UT WOS:000256549300040 ER PT J AU Yu, HD Zhang, JS Li, N AF Yu, Huidan Zhang, Jinsuo Li, Ning TI Lattice Boltzmann simulation of mass transfer in thermally driven cavity flows SO PROGRESS IN COMPUTATIONAL FLUID DYNAMICS LA English DT Article DE lattice Boltzmann Method; LBM; Boussinesq equations; thermally driven cavity flow; heat and mass transfer; natural convection ID NATURAL-CONVECTION; BGK MODEL; BOUSSINESQ EQUATIONS; SQUARE CAVITY; SIDE AB We study mass transfer in 2D thermally driven cavity using lattice Boltzmann method. Simulations are performed to investigate various effects on enhancement of oxygen mass transfer in lead/lead-bismuth eutectic. It is shown that oxygen transfer is dominated by convection although diffusion plays a role. Comparative studies demonstrate that side-heating and top-cooling configuration is more efficient than side-heating/cooling and oxygen transfers more rapidly in a square than rectangular cavity with same area. This work supplies supportive information for developing active oxygen control technique in experiments to prevent or reduce corrosion in liquid metal cooled nuclear reactors. C1 [Yu, Huidan] Los Alamos Natl Lab, Comp Computat & Sci Div, Ctr Nonlinear Studies, Los Alamos, CA USA. [Zhang, Jinsuo] Los Alamos Natl Lab, Decis Applicat Div, Los Alamos, CA USA. [Li, Ning] Los Alamos Natl Lab, Mat Phys & Applicat Div, Los Alamos, CA USA. RP Yu, HD (reprint author), Los Alamos Natl Lab, Comp Computat & Sci Div, Ctr Nonlinear Studies, Los Alamos, CA USA. EM hyu@lanl.gov; jszhang@lanl.gov; ningli@lanl.gov RI Zhang, Jinsuo/H-4717-2012 OI Zhang, Jinsuo/0000-0002-3412-7769 NR 23 TC 0 Z9 1 U1 0 U2 2 PU INDERSCIENCE ENTERPRISES LTD PI GENEVA PA WORLD TRADE CENTER BLDG, 29 ROUTE DE PRE-BOIS, CASE POSTALE 896, CH-1215 GENEVA, SWITZERLAND SN 1468-4349 J9 PROG COMPUT FLUID DY JI Prog. Comput. Fluid Dyn. PY 2008 VL 8 IS 1-4 BP 206 EP 212 DI 10.1504/PCFD.2008.018091 PG 7 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA 305FP UT WOS:000256163500020 ER PT J AU Anwar, S Cortis, A Sukop, MC AF Anwar, Shadab Cortis, Andrea Sukop, Michael C. TI Lattice Boltzmann simulation of solute transport in heterogeneous porous media with conduits to estimate macroscopic continuous time random walk model parameters SO PROGRESS IN COMPUTATIONAL FLUID DYNAMICS LA English DT Article DE porous media; solute transport; lattice Boltzmann; CTRW ID ANISOTROPIC-DISPERSION-EQUATION; BOUNDARY-CONDITIONS; BGK MODEL; FLOW; ADVECTION AB Lattice Boltzmann models simulate solute transport in porous media traversed by conduits. Resulting solute breakthrough curves are fitted with Continuous Time Random Walk models. Porous media are simulated by damping flow inertia and, when the damping is large enough, a Darcy's Law solution instead of the Navier-Stokes solution normally provided by the lattice Boltzmann model is obtained. Anisotropic dispersion is incorporated using a direction-dependent relaxation time. Our particular interest is to simulate transport processes outside the applicability of the standard Advection-Dispersion Equation (ADE) including eddy mixing in conduits. The ADE fails to adequately fit any of these breakthrough curves. C1 [Anwar, Shadab; Sukop, Michael C.] Florida Int Univ, Dept Earth Sci, Miami, FL 33199 USA. [Cortis, Andrea] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Sukop, MC (reprint author), Florida Int Univ, Dept Earth Sci, Univ Pk, Miami, FL 33199 USA. EM sanwa001@fiu.edu; acortis@lbl.gov; sukopm@fiu.edu RI Cortis, Andrea/A-3525-2008; anwar, shadab/A-6844-2009; OI Sukop, Michael/0000-0002-2142-6292 NR 24 TC 5 Z9 5 U1 0 U2 6 PU INDERSCIENCE ENTERPRISES LTD PI GENEVA PA WORLD TRADE CENTER BLDG, 29 ROUTE DE PRE-BOIS, CASE POSTALE 856, CH-1215 GENEVA, SWITZERLAND SN 1468-4349 EI 1741-5233 J9 PROG COMPUT FLUID DY JI Prog. Comput. Fluid Dyn. PY 2008 VL 8 IS 1-4 BP 213 EP 221 DI 10.1504/PCFD.2008.018092 PG 9 WC Thermodynamics; Mechanics SC Thermodynamics; Mechanics GA 305FP UT WOS:000256163500021 ER PT J AU Hyde, R Ishikawa, M Myhrvold, N Nuckolls, J Wood, L AF Hyde, Roderick Ishikawa, Muriel Myhrvold, Nathan Nuckolls, John Wood, Lowell TI Nuclear fission power for 21st century needs: Enabling technologies for large-scale, low-risk, affordable nuclear electricity SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT COE-INES 2nd International Symposium on Innovative Nuclear Energy Systems for Sustainable Development of the World CY NOV 26-30, 2006 CL Yokohama, JAPAN SP COE-INES, Tokyo Inst Technol, Res Lab Nucl Reactors, Tokyo Inst Technol, Ctr Res Innovat Nucl Energy Syst, Atom Energy Soc Japan DE nuclear fission power; human energy needs; nuclear electricity AB We examine the principal concerns regarding provision of a large fraction of human energy needs with nuclear fission reactor-derived electricity, and offer robust physics and engineering responses to each of them. We then propose a representative system-level integration of these solutions to the longstanding problems that have confronted nuclear fission-based power. This integration obviates all fuel supply issues, including the entire set of isotopic enrichment ones, while rendering comparably useful as nuclear fuels all of the actinide elements and isotopes. It entirely avoids transport and reprocessing and the full set of ad hoc waste disposal issues, and completely precludes all those involving proliferation/diversion of fissile isotopes into weapons' programs. It offers high-grade heat in pressurized helium gas for thermodynamically efficient, economically appealing, environmentally attractive combined-cycle conversion to electricity while robustly avoiding prospects of internal overheating of any portion of the reactor's core or fuel. It provides highly redundant means of any desired statistical reliability for prevention of core meltdown in LOCA circumstances. It provides zero biospheric hazard in event of either natural or man-made catastrophe. It requires - indeed, admits of - no operator control actions, other than initial start-up and final shutdown commands, so that operator errors are entirely precluded; during the half-century of potentially full-power operational life in between these two commands, it thermostatically regulates in an entirely automatic manner its own nuclear power generation to match the heat removed from its core in a time-varying fashion. The thorium-burning variant of this new class of reactors involves no long-lived actinide isotopes, thereby obviating a present-day keystone issue of long-term reactor waste storage and disposal. Each of these novel features is technologically separable, so that these new reactor design concepts may be applied piecewise to enhance prospects of nuclear reactor-centered power generation in many different utilization circumstances. However, synergisms arising from their full integration seem likely to be compellingly attractive in most situations, for a constellation of economic and safety reasons. We therefore project a bright future for cheap electricity safely obtained in > 10 TWe quantities from nuclear power reactors of this new type, moreover over multi-century time frames. We observe that pertinent aspects of neutron physics and modem technology together offer a far richer spectrum of possibilities for nuclear power reactors than has been significantly explored through the present; the present architecture is merely exemplary. (C) 2007 Elsevier Ltd. All rights reserved. C1 [Hyde, Roderick; Ishikawa, Muriel; Nuckolls, John; Wood, Lowell] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. [Hyde, Roderick; Ishikawa, Muriel; Myhrvold, Nathan; Wood, Lowell] Intellectual Ventures LLP, Bellevue, WA 98004 USA. [Wood, Lowell] Stanford Univ, Hoover Inst, Stanford, CA 94305 USA. RP Wood, L (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. EM lowellwood@comcast.net NR 0 TC 5 Z9 5 U1 0 U2 15 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2008 VL 50 IS 2-6 BP 82 EP 91 DI 10.1016/j.pnucene.2007.10.027 PG 10 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 282WS UT WOS:000254598500006 ER PT J AU Li, N AF Li, Ning TI Lead-alloy coolant technology and materials - technology readiness level evaluation SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT COE-INES 2nd International Symposium on Innovative Nuclear Energy Systems for Sustainable Development of the World CY NOV 26-30, 2006 CL Yokohama, JAPAN SP COE-INES, Tokyo Inst Technol, Res Lab Nucl Reactors, Tokyo Inst Technol, Ctr Res Innovat Nucl Energy Syst, Atom Energy Soc Japan DE lead-alloy coolant; technology readiness level; oxygen control; corrosion; materials testing; spallation target ID ACCELERATOR-DRIVEN SYSTEMS; BISMUTH COOLANT; MOLTEN LEAD; OXYGEN; CORROSION; REACTOR; IRRADIATION; BEHAVIOR; STEEL; LOOP AB Lead and lead-bismuth eutectic heavy liquid metal coolants are under wide-ranging international investigation and development for advanced nuclear systems for energy production and waste transmutation (reactor-based or accelerator-driven). This report reviews the major supporting international R&D programs, the key advances in the main areas of coolant technology and materials, the state of technology, and the strategic directions for further development. Based on this review, we conservatively evaluate the technological readiness level (TRL) for programmatic and industrial applications in high-temperature advanced reactors to be 7, "one-dimensional engineering-scale demonstration", or the first level in the proof-of-performance category. A 3-D engineering-scale integral test and demonstration facility should be the next step toward the realization of a test and demonstration nuclear system (reactor or accelerator-driven). The recent success of MEGAPIE, a 1 MW class lead-bismuth eutectic spallation target operating at the Paul Scherrer Institute signals that for such applications of short to intermediate durations at moderate temperatures, the TRL is close to 9, meaning the technology is nearly ready for deployment. (C) 2007 Elsevier Ltd. All rights reserved. C1 Los Alamos Natl Lab, Los Alamos, NM USA. RP Li, N (reprint author), Los Alamos Natl Lab, POB 1663,MS H816, Los Alamos, NM USA. EM ningli@lanl.gov NR 55 TC 27 Z9 27 U1 2 U2 20 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2008 VL 50 IS 2-6 BP 140 EP 151 DI 10.1016/j.pnucene.2007.10.016 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 282WS UT WOS:000254598500016 ER PT J AU Lewis, D AF Lewis, David TI Hydrogen and its relationship with nuclear energy SO PROGRESS IN NUCLEAR ENERGY LA English DT Article; Proceedings Paper CT COE-INES 2nd International Symposium on Innovative Nuclear Energy Systems for Sustainable Development of the World CY NOV 26-30, 2006 CL Yokohama, JAPAN SP COE-INES, Tokyo Inst Technol, Res Lab Nucl Reactors, Tokyo Inst Technol, Ctr Res Innovat Nucl Energy Syst, Atom Energy Soc Japan DE nuclear; hydrogen; sustainability; transportation; coal AB In broad terms it is estimated that the world will need 17 TW of additional primary energy to meet its needs by 2050. Much of this growth in energy demand will take place in developing countries. Wind, biomass, solar, nuclear and coal will all compete to fill this gap as oil market share declines. Economics, environmental issues, and public acceptance elements of sustainable development goals will be as important as the engineering issues of efficiency and reliability in this competition. Nuclear power is increasingly recognized as a principal contender to provide economic, "carbon free" electricity for the grid, but it does not directly provide a transportation fuel as flexible as is gasoline. Nuclear-produced hydrogen might help to fill this transportation fuel gap. This presentation will discuss the processes for manufacture of hydrogen from nuclear heat, and the integration of nuclear-produced hydrogen into the transportation fuel system - in part via synergies with traditional oil, natural gas and coal, and/or synergies with nontraditional shale and tar sands. We will discuss the nuclear hydrogen system as we expect it to appear in 2050 and will discuss some of processes that will provide a pathway to creating that system. (C) 2007 Published by Elsevier Ltd. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Lewis, D (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM david.lewis@anl.gov NR 19 TC 19 Z9 20 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-1970 J9 PROG NUCL ENERG JI Prog. Nucl. Energy PY 2008 VL 50 IS 2-6 BP 394 EP 401 DI 10.1016/j.pnucene.2007.11.072 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 282WS UT WOS:000254598500057 ER PT S AU Nunokawa, H Parke, S Valle, JWF AF Nunokawa, Hiroshi Parke, Stephen Valle, Jose W. F. BE Faessler, A TI CP violation and neutrino oscillations SO PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 60, NO 2 SE Progress in Particle and Nuclear Physics LA English DT Review DE neutrinos; oscillations; CP violation; astro-particle physics ID DOUBLE-BETA-DECAY; RECONCILING DARK-MATTER; LEPTON-FLAVOR VIOLATION; QUASI-DIRAC NEUTRINOS; R-PARITY BREAKING; MASSLESS NEUTRINOS; T-VIOLATION; 3-NEUTRINO OSCILLATIONS; MAJORANA NEUTRINOS; MASSIVE NEUTRINOS AB We review the basic mechanisms of neutrino mass generation and the corresponding structure of the lepton mixing matrix. We summarize the status of three-neutrino oscillation parameters as determined from current observations, using state-of-the-art solar and atmospheric neutrino fluxes, as well as latest experimental data as of September 2007. We also comment on recent attempts to account for these results and to understand flavour from first principles. We discuss extensively the prospects of probing the strength of CP violation in two near term accelerator neutrino oscillation experiments, T2K and NOvA, as well as possible extensions such as T2KK and a second large off-axis detector near the NOM detector. We also briefly discuss the possibility of probing the effect of Majorana phases in future neutrinoless double beta decay searches and discuss other implications of leptonic CP violation such as leptogenesis. Finally we comment on the issue of robustness of the current oscillation interpretation and possible ways of probing for non-standard neutrino interactions in precision oscillation studies. (c) 2007 Elsevier B.V. All rights reserved. C1 [Valle, Jose W. F.] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, E-46071 Valencia, Spain. [Nunokawa, Hiroshi] Pontificia Univ Catolica Rio de Janeiro, Dept Fis, BR-22452970 Rio De Janeiro, Brazil. [Parke, Stephen] Fermilab Natl Accelerator Lab, Dept Theoret Phys, Batavia, IL 60510 USA. RP Valle, JWF (reprint author), Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Edificio Inst Paterna Apartado 22085, E-46071 Valencia, Spain. EM valle@ific.uv.es RI Valle, Jose W.F./F-7573-2013; OI Valle, Jose W.F./0000-0002-1881-5094; Parke, Stephen/0000-0003-2028-6782 NR 248 TC 114 Z9 114 U1 1 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0146-6410 J9 PROG PART NUCL PHYS PY 2008 VL 60 IS 2 BP 338 EP 402 DI 10.1016/j.ppnp.2007.10.001 PG 65 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BHQ40 UT WOS:000255395100002 ER PT S AU Roberts, CD AF Roberts, C. D. BE Faessler, A TI Hadron properties and Dyson-Schwinger equations SO PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 61, NO 1 SE PROGRESS IN PARTICLE AND NUCLEAR PHYSICS LA English DT Article; Proceedings Paper CT International Workshop on Nuclear Physics/29th Course on Quarks in Hadrons and Nuclei CY SEP 16-24, 2007 CL Erice, ITALY SP Ettotrez Majorana Ctr Sci Culture DE Bethe-Salpeter equations; confinement; dynamical chiral symmetry breaking; Dyson-Schwinger equations; covariant Faddeev equation; meson spectroscopy; nucleon form factors; hadron physics ID CHIRAL-SYMMETRY BREAKING; QUARK-DIQUARK MODEL; U(1) PROBLEM; QUANTUM ELECTRODYNAMICS; LADDER APPROXIMATION; INFRARED BEHAVIOR; DECAY CONSTANT; BOUND-STATES; SIGMA-TERMS; QCD AB An overview of the theory and phenomenology of hadrons and QCD is provided from a Dyson-Schwinger equation viewpoint. Following a discussion of the definition and realization of light-quark confinement, the nonperturbative nature of the running mass in QCD and inferences from the gap equation relating to the radius of convergence for expansions of observables in the current-quark mass are described. Some exact results for pseudoscalar mesons are also highlighted, with details relating to the U-A(1) problem, and calculated masses of the lightest J = 0, 1 states are discussed. Studies of nucleon properties are recapitulated upon and illustrated: through a comparison of the In-weighted ratios of Pauli and Dirac form factors for the neutron and proton; and a perspective on the contribution of quark orbital angular momentum to the spin of a nucleon at rest. Comments on prospects for the future of the study of quarks in hadrons and nuclei round out the contribution. (c) 2008 Elsevier B.V. All rights reserved. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Roberts, CD (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. EM cdroberts@anl.gov OI Roberts, Craig/0000-0002-2937-1361 NR 94 TC 101 Z9 101 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0146-6410 J9 PROG PART NUCL PHYS PY 2008 VL 61 IS 1 BP 50 EP 65 DI 10.1016/j.ppnp.2007.12.034 PG 16 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BIA34 UT WOS:000257886300005 ER PT S AU Thomas, AW AF Thomas, A. W. BE Faessler, A TI The spin of the proton SO PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 61, NO 1 SE Progress in Particle and Nuclear Physics LA English DT Review CT International Workshop on Nuclear Physics/29th Course on Quarks in Hadrons and Nuclei CY SEP 16-24, 2007 CL Erice, ITALY SP Ettotrez Majorana Ctr Sci Culture DE proton spin; spin crisis; chiral symmetry; pion cloud; exchange current; polarized gluons; axial anomaly ID BAG MODEL; PARTON DISTRIBUTIONS; CHIRAL-SYMMETRY; DELTA-G/G; NUCLEON; DEPENDENCE; ASYMMETRY; DEUTERON AB The twenty years since the announcement of the proton spin crisis by the European Muon Collaboration has seen tremendous progress in our knowledge of the distribution of spin within the proton. The problem is reviewed, beginning with the original data and the suggestion that polarized gluons may play a crucial role in resolving the problem through the U(l) axial anomaly. The discussion continues to the present day where not only have strong limits been placed on the amount of polarized glue in the proton but the experimental determination of the spin content has also become much more precise. It is now clear that the origin of the discrepancy between the experiment and the naive expectation of the fraction of spin carried by the quarks and anti-quarks in the proton lies in the non-perturabtive structure of the proton. We explain how the features expected in a modern, relativistic and chirally symmetric description of nucleon structure naturally explain the current data. (c) 2008 Elsevier B.V. All rights reserved. C1 [Thomas, A. W.] Jefferson Lab, Newport News, VA 23606 USA. RP Thomas, AW (reprint author), Thomas Jefferson Natl Accelerator Facil, Jefferson Lab Chief Scientist & Director Theory C, 12000 Jefferson Ave Suite 1, Newport News, VA 23606 USA. EM awthomas@jlab.org RI Thomas, Anthony/G-4194-2012 OI Thomas, Anthony/0000-0003-0026-499X NR 60 TC 22 Z9 22 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0146-6410 J9 PROG PART NUCL PHYS PY 2008 VL 61 IS 1 BP 219 EP 228 DI 10.1016/j.ppnp.2007.12.039 PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BIA34 UT WOS:000257886300032 ER PT S AU de Jager, K AF de Jager, Kees BE Faessler, A TI Recent experimental results from JLab SO PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 61, NO 1 SE PROGRESS IN PARTICLE AND NUCLEAR PHYSICS LA English DT Article; Proceedings Paper CT International Workshop on Nuclear Physics/29th Course on Quarks in Hadrons and Nuclei CY SEP 16-24, 2007 CL Erice, ITALY SP Ettotrez Majorana Ctr Sci Culture DE lepton-induced reactions; polarization phenomena in reactions; nuclear tests of fundamental symmetries; quarks; gluons and QCD in nuclear reactions; hypernuclei ID NEUTRAL PION; SCATTERING; LIFETIME; NUCLEON; WIDTH AB Preliminary results of a selected few recent experiments at JLab are presented. Published by Elsevier B.V. C1 Jefferson Lab, Newport News, VA 23606 USA. RP de Jager, K (reprint author), Jefferson Lab, Newport News, VA 23606 USA. EM kees@jlab.org NR 51 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0146-6410 J9 PROG PART NUCL PHYS PY 2008 VL 61 IS 1 BP 311 EP 324 DI 10.1016/j.ppnp.2007.12.017 PG 14 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BIA34 UT WOS:000257886300045 ER PT S AU Klein, M Yoshida, R AF Klein, M. Yoshida, R. BE Faessler, A TI Collider physics at HERA SO PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 61, NO 2 SE Progress in Particle and Nuclear Physics LA English DT Review DE HERA; Deep inelastic scattering; Structure functions; Photoproduction; Diffraction; Heavy flavours; Searches; QCD; Electroweak physics ID DEEP-INELASTIC-SCATTERING; PROTON STRUCTURE-FUNCTION; CURRENT CROSS-SECTIONS; HEAVY FLAVOR PRODUCTION; TO-LEADING ORDER; VIRTUAL COMPTON-SCATTERING; LEPTON-NUCLEON SCATTERING; STRUCTURE-FUNCTION F-2; STRUCTURE-FUNCTION F2; H1 VERTEX DETECTOR AB From 1992 to 2007, HERA, the first electron-proton collider, operated at cms energies of about 320 GeV and allowed the investigation of deep-inelastic and photoproduction processes at the highest energy scales accessed thus far. This review is an introduction to, and a summary of, the main results obtained at HERA during its operation. (C) 2008 Elsevier B.V. All rights reserved. C1 [Yoshida, R.] Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. [Klein, M.] Univ Liverpool, Dept Phys, Liverpool L69 7ZE, Merseyside, England. RP Yoshida, R (reprint author), Argonne Natl Lab, HEP Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM ryoshida@hep.anl.gov FU U.S. Department of Energy [DE-AC02-06CH11357] FX RY's work at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, under contract DE-AC02-06CH11357. NR 310 TC 29 Z9 29 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0146-6410 J9 PROG PART NUCL PHYS PY 2008 VL 61 IS 2 BP 343 EP 393 DI 10.1016/j.ppnp.2008.05.002 PG 51 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA BII92 UT WOS:000259921900002 ER PT S AU Bader, BW Puretskiy, AA Berry, MV AF Bader, Brett W. Puretskiy, Andrev A. Berry, Michael V. BE RuizShulcloper, J Kropatsch, WG TI Scenario Discovery Using Nonnegative Tensor Factorization SO PROGRESS IN PATTERN RECOGNITION, IMAGE ANALYSIS AND APPLICATIONS, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 13th Iberoamerican Congress on Progress in Pattern Recognition, Image Analysis and Applications CY SEP 09-12, 2008 CL Havana, CUBA SP Adv Technol Applicat Ctr, Int Assoc Pattern Recognit, Cuban Assoc Pattern Recognit, Cuban Soc Math & Comp Sci, Mexican Assoc Comp Vis, Neural Comp & Robotics, SIGPR-SBC, Spanish Assoc Pattern Recognit & Image Anal, Portuguese Assoc Pattern Recognit DE nonnegative tensor factorization; PARAFAC; scenario discovery; VAST 2007; visual analytics ID ALGORITHMS AB In the relatively new field of visual analytics there is a great need for automated approaches to both verify and discover the intentions and schemes of primary actors through time. Data mining and knowledge discovery play critical roles in facilitating the ability to extract meaningful information from large and complex textual-based (digital) collections. In this study, we develop a mathematical strategy based on nonnegative tensor factorization (NTF) to extract and sequence important activities and specific events from sources such as news articles. The ability to automatically reconstruct a plot or confirm involvement in a questionable activity is greatly facilitated by our approach. As a variant of the PARAFAC multidimensional data model, we apply our NTF algorithm to the terrorism-based scenarios of the VAST 2007 Contest data set to demonstrate how term-by-entity associations can be used for scenario/plot discovery and evaluation. C1 [Bader, Brett W.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Puretskiy, Andrev A.; Berry, Michael V.] Univ Tennessee, Dept Elect Engn & Comp Sci, Knoxville, TN 37996 USA. RP Bader, BW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM bwbader@sandia.gov; puretski@eecs.utk.edu; berry@eecs.utk.edu OI Berry, Michael/0000-0002-9191-9148 FU United States Department of Energy; Sandia National Laboratory, a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy [DEAC0494AL85000] FX This research was sponsored by the United States Department of Energy and by Sandia National Laboratory, a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DEAC0494AL85000. NR 16 TC 3 Z9 4 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-85919-2 J9 LECT NOTES COMPUT SC PY 2008 VL 5197 BP 791 EP + PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Imaging Science & Photographic Technology SC Computer Science; Imaging Science & Photographic Technology GA BII86 UT WOS:000259899200096 ER PT J AU Green, MA Emery, K Hishikawa, Y Warta, W AF Green, Martin A. Emery, Keith Hishikawa, Yoshihiro Warta, Wilhelm TI Solar cell efficiency tables (version 31) SO PROGRESS IN PHOTOVOLTAICS LA English DT Article DE solar cell efficiency; photovoltaic efficiency; energy conversion efficiency ID 20-PERCENT EFFICIENCY; MULTICRYSTALLINE AB Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July, 2008 are reviewed. Copyright (C) 2007 John Wiley & Sons, Ltd. C1 [Green, Martin A.] Univ New S Wales, ARC Photovolta Ctr Excellence, Sydney, NSW 2052, Australia. [Emery, Keith] Natl Renewable Energy Lab, Golden, CO 80401 USA. [Hishikawa, Yoshihiro] Natl Inst Adv Ind Sci & Technol, RCPV, Tsukuba, Ibaraki, Japan. [Warta, Wilhelm] Fraunhofer Inst Solar Energy Syst, Dept Solar Cells Mat & Technol, D-79110 Freiburg, Germany. RP Green, MA (reprint author), Univ New S Wales, ARC Photovolta Ctr Excellence, Sydney, NSW 2052, Australia. EM m.green@unsw.edu.au NR 48 TC 161 Z9 167 U1 6 U2 40 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD JAN PY 2008 VL 16 IS 1 BP 61 EP 67 DI 10.1002/pip.808 PG 7 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 252QL UT WOS:000252461600005 ER PT J AU Mannarelli, M Rajagopal, K Sharma, R AF Mannarelli, Massimo Rajagopal, Krishna Sharma, Rishi TI Rigid Crystalline Color Superconducting Quark Matter SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article ID FREE PRECESSION; QCD; PULSAR; PHASE AB Cold three flavor quark matter at large (but not asymptotically large) densities may exist in a crystalline color superconducting phase. These phases are characterized by a gap parameter Delta that varies periodically in space, forming a crystal structure. A Ginzburg-Landau expansion in Delta shows that two crystal structures based on cubic symetry are particularly favorable, and may be the ground state of matter at densities present in neutron star cores. By deriving the effective action for the phonon fields that describe space- and time-dependent fluctuations of the crystal structure formed by 6, one can obtain its shear modulus. Within a Ginzburg-Landau approximation, we find shear moduli which are 20 to 1000 times larger than those of neutron star crusts. This phase of matter is thus more rigid than any known material in the universe, but at the same time the crystalline color superconducting phase is also superfluid. These properties raise the possibility that the presence of this phase within neutron stars may have distinct implications for their phenomenology. For example, (some) pulsar glitches may originate in crystalline superconducting neutron star cores. C1 [Mannarelli, Massimo] Fac Ciencias, IEEC CSIC, Barcelona, Spain. [Rajagopal, Krishna] MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. [Sharma, Rishi] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Mannarelli, M (reprint author), Fac Ciencias, IEEC CSIC, Campus UAB, Barcelona, Spain. FU DoE Office of Nuclear Physics [DE-AC02-05CH11231, DF-FC02-94ER40818]; LANS; LLC [DE-AC52-06NA25396] FX Rishi Sharma thanks the organizers of the workshop on "New Frontiers in QCD" and the complementary YITP international symposium on "Fundamental Problems in Hot and/or Dense QCD", for giving us an opportunity to present our work. MM has been supported by the "Bruno Rossi" fellowship program. This research was supported in part by the DoE Office of Nuclear Physics, contract numbers #DE-AC02-05CH11231, #DF-FC02-94ER40818 and LANS, LLC contract #DE-AC52-06NA25396. NR 54 TC 4 Z9 4 U1 0 U2 0 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 2008 IS 174 BP 39 EP 47 PG 9 GA 365WI UT WOS:000260439700004 ER PT J AU Hidaka, Y Pisarski, RD AF Hidaka, Yoshimasa Pisarski, Robert D. TI Suppression of the Shear Viscosity as QCD Cools into a Confining Phase SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article AB We consider QCD near but above T-c. Lattice simulation shows that the pressure, susceptibilities and renormalized Polyakov loop, which are static observables, dramatically change tip to a couple of T-c We show that the shear viscosity, which is one of dynamical observables, also dramatically changes, and is suppressed by two powers of the Polyakov loop near T, in perturbation theory [Y. Hidaka and R. D. Pisarski, arXiv:0803.0453]. This suggests that eta/T-3 decreases markedly as QCD cools down to temperatures near T-c C1 [Hidaka, Yoshimasa] RIKEN BNL Res Ctr, Brookhaven Natl Lab, Upton, NY 11973 USA. [Pisarski, Robert D.] Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Hidaka, Y (reprint author), RIKEN BNL Res Ctr, Brookhaven Natl Lab, Upton, NY 11973 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 2008 IS 174 BP 228 EP 232 PG 5 GA 365WI UT WOS:000260439700031 ER PT J AU Kojo, T Jido, D AF Kojo, Toru Jido, Daisuke TI QCD Sum Rules and 1/N(c) Expansion SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article AB The 1/N(c) arguments are developed to classify the hadronic states in the correlators. Arguments applied to the sigma meson correlator enable to separate the instanton, glueball, and, in particular, the pi pi scattering states by 1/N(c), from both 2q and 4q correlators. The bare resonance pole with no mixing effects are analyzed with the QCD sum rules (QSR). The results suggest the existence of nontrivial correlation for the mass reduction of 4q system. C1 [Kojo, Toru] Brookhaven Natl Lab, RBRC, Upton, NY 11973 USA. [Jido, Daisuke] Kyoto Univ, Yukawa Inst Theoret Phys, Kyoto 6068502, Japan. RP Kojo, T (reprint author), Brookhaven Natl Lab, RBRC, Upton, NY 11973 USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 2008 IS 174 BP 258 EP 261 PG 4 GA 365WI UT WOS:000260439700038 ER PT J AU Nawa, K Suganuma, H Kojo, T AF Nawa, Kanabu Suganuma, Hideo Kojo, Toru TI Baryonic Matter in Holographic QCD SO PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT LA English DT Article ID SKYRME MODEL AB We study baryons and baryonic matter in holographic QCD with D4/D8/(D8) over bar multi-D brane system. In large-N(c) holographic QCD, the baryon appears as a topologically non-trivial chiral soliton, which is called "brane-induced Skyrmion". We also analyze the features of the baryonic matter in holographic QCD by investigating the system of single brane-induced Skyrmion on a three-dimensional closed manifold S(3). We propose a new interesting picture of "pion dominance" near the critical density. C1 [Nawa, Kanabu] Osaka Univ, RCNP, Ibaraki 5670047, Japan. [Suganuma, Hideo] Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. [Kojo, Toru] Brookhaven Natl Lab, RBRC, Upton, NY 11973 USA. RP Nawa, K (reprint author), Osaka Univ, RCNP, Ibaraki 5670047, Japan. NR 15 TC 4 Z9 4 U1 1 U2 1 PU PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PI KYOTO PA C/O KYOTO UNIV, YUKAWA HALL, KYOTO, 606-8502, JAPAN SN 0375-9687 J9 PROG THEOR PHYS SUPP JI Prog. Theor. Phys. Suppl. PY 2008 IS 174 BP 347 EP 352 PG 6 GA 365WI UT WOS:000260439700050 ER PT S AU Martin, S Brown, WM Faulon, JL AF Martin, Shawn Brown, W. Michael Faulon, Jean-Loup BE Werther, M Seitz, H TI Using Product Kernels to Predict Protein Interactions SO PROTEIN - PROTEIN INTERACTION SE Advances in Biochemical Engineering-Biotechnology LA English DT Article; Book Chapter DE beta-strand interactions; Product kernels; Protein-chemical interactions; Protein-protein interactions; Support Vector Machines ID SIGNATURE MOLECULAR DESCRIPTOR; SECONDARY STRUCTURE PREDICTION; EXTENDED VALENCE SEQUENCES; ANTIPARALLEL BETA-SHEETS; SUPPORT VECTOR MACHINES; INTERACTION NETWORKS; GRAPH KERNELS; RESOURCE; DATABASE; DETERMINANTS AB There is a wide variety of experimental methods for the identification of protein interactions. This variety has in turn spurred the development of numerous different computational approaches for modeling and predicting protein interactions. These methods range from detailed structure-based methods capable of operating on only a single pair of proteins at a time to approximate statistical methods capable of making predictions on multiple proteomes simultaneously. in this chapter, we provide a brief discussion of the relative merits of different experimental and computational methods available for identifying protein interactions. Then we focus on the application of our particular (computational) method using Support Vector Machine product kernels. We describe our method in detail and discuss the application of the method for predicting protein-protein interactions, beta-strand interactions, and protein-chemical interactions. C1 [Martin, Shawn; Brown, W. Michael; Faulon, Jean-Loup] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Martin, S (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM smartin@sandia.gov FU U.S. Department of Energy's Genomics; Sandia Laboratory Directed Research and Development; Sandia Corporation; Lockheed Martin Company; United States Department of Energy's National Nuclear Security Administration [DE-AC04-94AL85000] FX This work was funded in part by the U.S. Department of Energy's Genomics: GTL program (www.doegenomestolife.org) under project "Carbon Sequestration in Synechococcus Sp.: From Molecular Machines to Hierarchical Modeling" (www.genomes-to-life.org). This work was also funded by Sandia Laboratory Directed Research and Development. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. NR 74 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0724-6145 BN 978-3-540-68817-4 J9 ADV BIOCHEM ENG BIOT JI Adv. Biochem. Eng. Biotechnol. PY 2008 VL 110 BP 215 EP 245 DI 10.1007/10_2007_084 D2 10.1007/978-3-540-68820-4 PG 31 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA BIK39 UT WOS:000260375400010 PM 17922100 ER PT J AU Mirkin, N Jaconcic, J Stojanoff, V Moreno, A AF Mirkin, Nurit Jaconcic, Jean Stojanoff, Vivian Moreno, Abel TI High resolution X-ray crystallographic structure of bovine heart cytochrome c and its application to the design of an electron transfer biosensor SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article DE electrocrystallization; cytochrome c from bovine heart mitochondria; gel acupuncture method; atomic force microscopy; X-ray diffraction ID GEL-ACUPUNCTURE METHOD; LOW IONIC-STRENGTH; CHEMICAL-PROPERTIES; FERRICYTOCHROME-C; HETEROGENEITY; REDUCTION; CRYSTALLIZATION; BEHAVIOR AB Cytochrome c is one of the most studied protein., probably due to its electron-transfer properties in aerobic and anaerobic respiration. Particularly, cytochrome c from bovine heart is a small protein, M, 12,230 Da, globular (hydrodynamic diameter of 3.4 nm), soluble in different buffer solutions, and commercially available. Despite being a quite well-studied protein and relatively easy to manipulate from the biochemical and electrochemical viewpoint, its 3D structure has never been published. In this work, the purification, crystallization and 3D structure of one of the cytochrome c isoforms is presented to 1.5 angstrom resolution. It is also shown how the presence of isoforms made both the purification and crystallization steps difficult. Finally, a new approach for protein electro-crystallization and design of biosensors is presented. C1 [Moreno, Abel] Univ Nacl Autonoma Mexico, Inst Quim, Mexico City 04510, DF, Mexico. [Mirkin, Nurit] CUNY, Hunter Coll, New York, NY 10021 USA. [Jaconcic, Jean; Stojanoff, Vivian] NSLS, Brookhaven Natl Lab, Upton, NY USA. RP Moreno, A (reprint author), Univ Nacl Autonoma Mexico, Inst Quim, Mexico City 04510, DF, Mexico. EM carcamo@servidor.unam.mx RI stojanoff, vivian /I-7290-2012 OI stojanoff, vivian /0000-0002-6650-512X FU NIGMS NIH HHS [GM0080] NR 27 TC 50 Z9 52 U1 0 U2 11 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-3585 J9 PROTEINS JI Proteins PD JAN PY 2008 VL 70 IS 1 BP 83 EP 92 DI 10.1002/prot.21452 PG 10 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 242BI UT WOS:000251699100009 PM 17634981 ER PT J AU Nocek, B Mulligan, R Bargassa, M Collart, F Joachimiak, A AF Nocek, B. Mulligan, R. Bargassa, M. Collart, F. Joachimiak, A. TI Crystal structure of aminopeptidase N from human pathogen Neisseria meningitidis SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article DE aminopeptidase N; PepN; active site Zn ion binding; SAD phasing; structural genomics ID PROTEIN-STRUCTURE; HIGH-THROUGHPUT; MODEL; METALLOPEPTIDASES; ALIGNMENT; FAMILIES C1 [Nocek, B.; Mulligan, R.; Bargassa, M.; Collart, F.; Joachimiak, A.] Argonne Natl Lab, Biosci Div, Midwest Ctr Struct Genom, Argonne, IL 60439 USA. [Nocek, B.; Mulligan, R.; Bargassa, M.; Collart, F.; Joachimiak, A.] Argonne Natl Lab, Biosci Div, Struct Biol Ctr, Argonne, IL 60439 USA. [Joachimiak, A.] Univ Chicago, Dept Biochem & Mol Biol, Chicago, IL 60637 USA. RP Joachimiak, A (reprint author), Argonne Natl Lab, Biosci Div, Midwest Ctr Struct Genom, 9700 S Cass Ave, Argonne, IL 60439 USA. EM andrzejj@anl.gov OI Collart, Frank/0000-0001-6942-4483 FU NIGMS NIH HHS [GM074942, GM62414, P50 GM062414, P50 GM062414-01, U54 GM074942, U54 GM074942-04S2] NR 30 TC 25 Z9 26 U1 0 U2 1 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0887-3585 J9 PROTEINS JI Proteins PD JAN PY 2008 VL 70 IS 1 BP 273 EP 279 DI 10.1002/prot.21276 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 242BI UT WOS:000251699100027 PM 17876832 ER PT S AU Wang, XP Kariuki, NN Niyogi, S Smith, MC Myers, DJ Hofmann, T Zhang, YF Bar, M Heske, C AF Wang, Xiaoping Kariuki, Nancy N. Niyogi, Suhas Smith, Matt C. Myers, Deborah J. Hofmann, Timo Zhang, Yufeng Baer, Marcus Heske, Clemens BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Bimetallic Palladium-Base Metal Nanoparticle Oxygen Reduction Electrocatalysts SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID MEMBRANE FUEL-CELLS; ALLOY ELECTROCATALYSTS; KINETICS; ORIGIN AB Bimetallic palladium-base metal nanoparticle catalysts are being investigated as alternatives to platinum-based catalysts for the oxygen reduction reaction (ORR) in polymer electrolyte fuel cells. We report here results on the palladium-copper, palladium-nickel, and palladium-iron systems. We are studying the effect of synthetic procedure, palladium to base metal ratio, heat treatment temperature, and heat treatment atmosphere on the ORR activity as well as on the valence band structure of these systems. palladium-copper nanoparticle catalysts synthesized by the colloidal technique with a composition of 75 mol% copper are the most active investigated thus far. This catalyst shows an ORR activity which is approximately 75% that of platinum (per gram of platinum-group metal). The corresponding valence band structure is strongly modified compared to that of I'd and Cu alone and resembles that of Pt, which is believed to be the reason for its superior performance among the other investigated platinum-free alternatives. C1 [Wang, Xiaoping; Kariuki, Nancy N.; Niyogi, Suhas; Smith, Matt C.; Myers, Deborah J.] Argonne Natl Lab, Chem Sci & Engn Div, Argonne, IL 60439 USA. RP Wang, XP (reprint author), Argonne Natl Lab, Chem Sci & Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 20 TC 5 Z9 5 U1 2 U2 9 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 109 EP 119 DI 10.1149/1.2981848 PG 11 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300011 ER PT S AU Wu, G Chen, ZW Artyushkova, K Garzon, FH Zelenay, P AF Wu, Gang Chen, Zhongwei Artyushkova, Kateryna Garzon, Fernando H. Zelenay, Piotr BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Polyaniline-derived Non-Precious Catalyst for the Polymer Electrolyte Fuel Cell Cathode SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID MOLECULAR-OXYGEN REDUCTION; FE-BASED CATALYSTS; HIGH-SURFACE-AREA; HIGH-TEMPERATURE; CARBON-BLACK; HEAT-TREATMENT; IRON; PYROLYSIS; ELECTROCATALYSTS; TETRAPHENYLPORPHYRINS AB This paper focuses on a new polyaniline-derived non-precious cathode catalyst with high oxygen-reduction activity, verified in electrochemical and fuel cell testing. The rotating disk (RDE) onset and half-wave potential (E) of oxygen reduction were measured at 0.90 V and 0.77 V, respectively. Rotating ring-disk electrode (RRDE) study revealed very good selectivity in the four-electron reduction, with H(2)O(2) yields below 1% (0.4% at 0.4 V). Similarly, the catalyst showed good performance in the hydrogen-air fuel cell, even at high cell operating voltages, yielding 0.04 A cm(-2) at 0.80 V and 0.21 A cm(-2) at 0.6 V. Fuel cell life test at a constant voltage of 0.4 V demonstrated promising stability up to 450 hours, generating a current density of approximately 0.32 A cm(-2), a respectable performance for a non-precious cathode catalysts operated on air rather than oxygen. Ex situ characterization pointed to pyridinic- and pyrrolic-nitrogen metal species as likely active ORR sites. C1 [Wu, Gang; Chen, Zhongwei; Garzon, Fernando H.; Zelenay, Piotr] Los Alamos Natl Lab, Mat Phys & Applicat Div, Los Alamos, NM 87545 USA. RP Wu, G (reprint author), Los Alamos Natl Lab, Mat Phys & Applicat Div, POB 1663, Los Alamos, NM 87545 USA. RI Wu, Gang/E-8536-2010; chen, zhongwei/A-5605-2015; OI Wu, Gang/0000-0003-4956-5208; Artyushkova, Kateryna/0000-0002-2611-0422 NR 26 TC 136 Z9 137 U1 7 U2 63 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 159 EP 170 DI 10.1149/1.2981852 PG 12 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300015 ER PT S AU Wipke, K Sprik, S Kurtz, J Garbak, J AF Wipke, K. Sprik, S. Kurtz, J. Garbak, J. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Fuel Cell Vehicle and Infrastructure Learning Demonstration Status and Results SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div AB The "Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project," is a five-year U.S. Department of Energy (DOE) project started in 2004. The purpose of this project is to conduct an integrated field validation that examines the performance of fuel cell vehicles and the supporting hydrogen infrastructure. NREL has analyzed data from almost three years of the five-year project. During this time, 92 vehicles have been deployed, 15 project refueling stations were placed in use, and no fundamental safety issues have been identified. We've analyzed data from over 200,000 individual vehicle trips covering 1,100,000 miles traveled and over 40,000 kg hydrogen produced or dispensed. Public analytical results for this project are in the form of composite data products, which aggregate individual performance into a range that protects the intellectual property and the identity of each company, while still publishing overall status and progress. C1 [Wipke, K.; Sprik, S.; Kurtz, J.] Natl Renewable Energy Lab, Hydrogen Technol & Syst Ctr, Golden, CO 80401 USA. RP Wipke, K (reprint author), Natl Renewable Energy Lab, Hydrogen Technol & Syst Ctr, Golden, CO 80401 USA. NR 5 TC 4 Z9 4 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 173 EP 184 DI 10.1149/1.2981853 PG 12 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300016 ER PT S AU Greeley, J AF Greeley, J. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI First-principles Investigations of Electrocatalysis and Corrosion SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID OXYGEN REDUCTION; HYDROGEN EVOLUTION; TRENDS; SPECTROSCOPY; SURFACES; ELECTROOXIDATION; NANOPARTICLES; ELECTRODES; ETHANOL; CO AB Three case studies of the use of Density Functional Theory calculations to model electrochemical phenomena are presented. These studies range from fundamental investigations of electrocatalytic reaction mechanisms to detailed atomistic analyses of dissolution and dealloying phenomena. The studies are intended to illustrate how first principles calculations are beginning to complement and enhance well-established experimental results in electrochemistry. C1 Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. RP Greeley, J (reprint author), Argonne Natl Lab, Ctr Nanoscale Mat, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 22 TC 0 Z9 0 U1 2 U2 10 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 209 EP 213 DI 10.1149/1.2981856 PG 5 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300019 ER PT S AU Davey, JR Mukundan, R Spendelow, J Hussey, DS Jacobson, DL Arif, M Borup, RL AF Davey, John R. Mukundan, Rangachary Spendelow, Jacob Hussey, Daniel S. Jacobson, David L. Arif, Muhammad Borup, Rodney L. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Water Dynamics in a PEM Fuel Cell: Effect of Current and Humidity Transients SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID TRANSPORT AB The water dynamics of the membrane electrode assembly (MEA) of a 50 cm(2) polymer electrolyte membrane (PEM) fuel cell was studied in response to current and humidity step transients as a function of inlet relative humidity (RH) and cell operating temperature. MEA water content change was monitored by high frequency resistance (HFR) and in situ neutron imaging. The MEA "wetting" response was significantly faster (10-30 seconds) than the reciprocal "drying" response (several minutes). The wetting response to increasing current appears faster than that to increasing gas inlet RH. Wetting and drying responses to gas inlet RH transients are greater at low current densities showing the dominating effect of current wetting over gas inlet humidity effects. Operating the fuel cell at 40 degrees C with no inlet gas humidification, a current wetting response was observed and 34 amps of current sustained. This showed that reaction water produced at the cathode is sufficient to support high current density if the drying effect of inlet gases is low. It also suggests that back diffusion of reaction water to the MEA is sufficient to account for the fast drop in HFR. In situ neutron imaging results show that GDL wetting is also faster than drying but on a slower time scale than that for the MEA. However, MEA and GDL drying are on a similar slow time scale and are coupled because water diffusing out of the MEA must move through the GDLs. C1 [Davey, John R.; Mukundan, Rangachary; Spendelow, Jacob; Borup, Rodney L.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Davey, JR (reprint author), Los Alamos Natl Lab, MS D429,MPA 11, Los Alamos, NM 87545 USA. OI Mukundan, Rangachary/0000-0002-5679-3930 NR 6 TC 4 Z9 4 U1 2 U2 7 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 329 EP 340 DI 10.1149/1.2981867 PG 12 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300030 ER PT S AU Shao, YY Kou, R Wang, J Kwak, JH Viswanathan, V Wang, Y Liu, J Lin, YH AF Shao, Yuyan Kou, Rong Wang, Jun Kwak, Ja Hun Viswanathan, Vish Wang, Yong Liu, Jun Lin, Yuehe BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Fast test for the durability of PEM fuel cell catalysts SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID ROTATING-DISK ELECTRODE; CARBON-BLACK; CATHODE CATALYST; SULFURIC-ACID; PLATINUM; SUPPORT; PT/C; DISSOLUTION; DEGRADATION; DEPOSITION AB ETek Pt/C catalyst was used as standard materials to develop a new test protocol for fast screening durable catalyst for PEM fuel cells. Potential step (Pstep) method with the upper potential of 1.4V under low potential of 0.85V/0.60V and the potential-static (Pstat) holding at 1.4 V or 1.2V are used to degrade the catalyst. The degradation in the electrochemical surface area (ESA) for Pt/C under Pstep conditions is greatly accelerated as compared with that under other conditions. The durability of Pt/Vulcan and Pt/CNT were studied using the new protocol with the electrochemical stressing of Pstep(1.4V/0.6V), which provided the same results as those tested using conventional protocols: Pt/CNT is more durable than Pt/Vulcan. This confirms that the new protocol works well in screening catalyst in terms of durability. The new protocol can differentiate the durability of electrocatalysts by shortening the test time to several hours. C1 [Shao, Yuyan; Kou, Rong; Wang, Jun; Kwak, Ja Hun; Viswanathan, Vish; Wang, Yong; Liu, Jun; Lin, Yuehe] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Shao, YY (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM yuehe.lin@pnl.gov RI Shao, Yuyan/A-9911-2008; Lin, Yuehe/D-9762-2011; Wang, Yong/C-2344-2013; Kwak, Ja Hun/J-4894-2014 OI Shao, Yuyan/0000-0001-5735-2670; Lin, Yuehe/0000-0003-3791-7587; NR 34 TC 4 Z9 4 U1 0 U2 5 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 361 EP 366 DI 10.1149/1.2981870 PG 6 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300033 ER PT S AU Chung, HT Johnston, CM Garzon, FH Zelenay, P AF Chung, Hoon T. Johnston, Christina M. Garzon, Fernando H. Zelenay, Piotr BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI A Non-Precious Electrocatalyst for Oxygen Reduction Based on Simple Heat-Treated Precursors SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID FUEL-CELLS; CATALYSTS; SUPPORTS AB An active, non-precious catalyst for electrochemical oxygen reduction was made by heat-treating simple precursors. The current density obtained in an H(2)/O(2) polymer electrolyte fuel cell (PEFC) was as high as 0.34 A/cm(2) MEA at 0.65 V. The oxygen-reduction activities of catalysts prepared at different temperatures over the range 800-1050 degrees C were shown to be equivalent by the rotating ring-disk electrode (RRDE) method. The nitrogen content, however, was observed by XPS to be highly variable with preparation temperature. Thus, in contrast to some reports in the literature, the surface nitrogen content was not strongly correlated to performance. The nature of the active site(s) is currently under investigation. C1 [Chung, Hoon T.; Johnston, Christina M.; Garzon, Fernando H.; Zelenay, Piotr] Los Alamos Natl Lab, Mat Phys & Applicat Div, Los Alamos, NM 87545 USA. RP Chung, HT (reprint author), Los Alamos Natl Lab, Mat Phys & Applicat Div, Los Alamos, NM 87545 USA. RI Chung, Hoon/A-7916-2012; Johnston, Christina/A-7344-2011 OI Chung, Hoon/0000-0002-5367-9294; NR 10 TC 15 Z9 15 U1 2 U2 10 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 385 EP 391 DI 10.1149/1.2981873 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300036 ER PT S AU Yang, RZ Dahn, TR Dahn, JR AF Yang, Ruizhi Dahn, Tara R. Dahn, J. R. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Fe-N-C Oxygen Reduction Catalysts Supported on Burned-off Activated Carbon SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID FUEL-CELLS AB Fe-N-C catalysts were prepared by impregnating FeCl(3) within two kinds of activated carbon (Kuraray GC and Nuchar) that had been previously burned-off at 500 degrees C in air to vary their pore sizes in a controlled way. The impregnated samples were subsequently heated at 850 degrees C in NH(3). The average pore size of the samples was determined by small-angle X-Ray scattering (SAXS) measurements and quantified by the radius of gyration (R(g)) of the pores. The catalytic activities of the samples vary with the pore size of the activated carbon, which depends on the bum-off time. The results support suggestions from the Dodelet group about the importance of the pore size in determining catalytic activity. C1 [Yang, Ruizhi] Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Yang, RZ (reprint author), Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. NR 8 TC 1 Z9 1 U1 1 U2 3 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 443 EP 447 DI 10.1149/1.2981878 PG 5 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300041 ER PT S AU Toney, MF Koh, S Yu, CF Strasser, P AF Toney, Michael F. Koh, Shirlaine Yu, Chengfei Strasser, Peter BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Use of Anomalous X-ray Scattering for Probing the Structure, Composition and Size of Binary Alloy Nanoparticle Electrocatalysts SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID OXYGEN REDUCTION; SURFACES AB X-ray diffraction (XRD) and small angle X-ray scattering (SAXS) are methods that are used to characterize the atomic structure and particle size of nanoparticle electrocatalysts. These methods do not inherently provide element specific information on structure and particle size. However, with the use of an anomalous scattering approach, one can obtain element specificity. This contribution describes these methods and applies these to fuel cell nanoparticle catalysts. C1 [Toney, Michael F.] Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Toney, MF (reprint author), Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RI Strasser, Peter/A-1868-2012 NR 20 TC 4 Z9 4 U1 0 U2 5 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 595 EP 601 DI 10.1149/1.2981894 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300057 ER PT S AU Lee, KS Kim, YS Pivovar, BS Lee, JS AF Lee, K. S. Kim, Y. S. Pivovar, B. S. Lee, J. S. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI MEA Fabrication and Fuel Cell Performance of Sulfonated Poly(Arylene Ether) with Cross-Linkable End Group SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID PROTON-EXCHANGE MEMBRANES; CATALYST LAYERS; STABILITY AB Partially fluorinated poly(arylene ether) copolymer having reactive functional group are used to fabricate the MEA to improve the interfacial adhesion between membrane and electrode. The optimum MEA processing procedure was studied using different hot pressing temperature and crosslinking. Good interfacial adhesion between hydrocarbon membrane and Nafion bonded electrode produced excellent fuel cell performance which was comparable to the MEA using Nafion 212. C1 [Lee, K. S.; Kim, Y. S.; Pivovar, B. S.] Los Alamos Natl Lab, Sensors & Electrochem Devices Grp, Los Alamos, NM 87545 USA. RP Lee, KS (reprint author), Los Alamos Natl Lab, Sensors & Electrochem Devices Grp, POB 1663, Los Alamos, NM 87545 USA. OI Lee, Kwan Soo/0000-0002-5315-3487 NR 13 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 825 EP 830 DI 10.1149/1.2981920 PG 6 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300083 ER PT S AU Mukherjee, PP Springer, TE Mukundan, R Hussey, DS Jacobson, DL Arif, M Borup, RL AF Mukherjee, P. P. Springer, T. E. Mukundan, R. Hussey, D. S. Jacobson, D. L. Arif, M. Borup, R. L. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Probing Liquid Water Profile in the Polymer Electrolyte Fuel Cell Membrane SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID NAFION(R) 117 MEMBRANES; MATHEMATICAL-MODEL; TRANSPORT AB Water transport in the ionomeric membrane, typically Nafion (R), has profound influence on the performance of the polymer electrolyte fuel cell, in terms of internal resistance and overall water balance. In this work, the response of Nafion (R) membrane water content and the resulting water gradient to fuel cell operational variability are investigated and the results from a theoretical modeling study are furnished along with reference to neutron imaging observations. C1 [Mukherjee, P. P.; Springer, T. E.; Mukundan, R.; Borup, R. L.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mukherjee, PP (reprint author), Los Alamos Natl Lab, MS D429,MPA 11, Los Alamos, NM 87545 USA. OI Mukundan, Rangachary/0000-0002-5679-3930 NR 11 TC 2 Z9 2 U1 0 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1027 EP 1033 DI 10.1149/1.2981943 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300106 ER PT S AU Kienitz, BL Zawodzinski, TA Pivovar, BS Garzon, FH AF Kienitz, B. L. Zawodzinski, T. A. Pivovar, B. S. Garzon, F. H. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Determining the Mechanisms of Cationic Contamination Affecting PEMFCs Using a Strip Cell Configuration SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID PERFORMANCE; AMMONIA AB Cationic contanmination of polymer electrolyte fuel cells has been shown to cause serious performance degradation but the exact mechanisms of this degradation are not fully understood. A strip cell configuration was devised to study the mechanisms of performance degradation due to cationic contamination by changing the time and length scales of traditional fuel cells while providing a suitable reference electrode. This "strip cell" configuration utilizes traditional Nafion (R) membranes in an in-plane configuration with electrodes painted on each end. Using this cell it was determined that cationic contaminants collect near the cathode of the fuel cell under load and that this profile leads to increased losses primarily in the cathode region. These results can be directly related to performance losses in a typical PEMFC contaminated by foreign cations. C1 [Kienitz, B. L.; Garzon, F. H.] Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Kienitz, BL (reprint author), Los Alamos Natl Lab, MPA 11, Los Alamos, NM 87544 USA. OI Kienitz, Brian/0000-0002-0648-0303 NR 7 TC 7 Z9 7 U1 0 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1069 EP 1078 DI 10.1149/1.2981948 PG 10 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300111 ER PT S AU Payne, TL Benjamin, TG Garland, NL Kopasz, JP AF Payne, T. L. Benjamin, T. G. Garland, N. L. Kopasz, J. P. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Research Strategies for Development of an Efficient and Effective Electrocatalyst for Polymer Electrolyte Membrane Fuel Cells and Progress Summary SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID OXYGEN REDUCTION; CATALYSTS AB The current electrocatalyst formulation for the polymer electrolyte membrane fuel cell (PEMFC), platinum supported on carbon (Pt/C), is known to be an effective promoter of redox reactions in fuel cells. However, the cost of Pt (currently similar to$2,000/troy ounce) hinders its use as a practical catalyst in commercial fuel cell-powered vehicles at current platinum loading. Another issue with respect to adoption of any electrocatalyst for vehicle applications is durability, especially in light of transportation drive cycle operation with start/stop, start-up/shut-down, and transient requirements. Thus, a robust alternative to current Pt/C technology is needed as the PEMFC electrocatalyst for the oxygen reduction reaction (ORR) on the cathode. The U.S. Department of Energy is funding cathode catalyst research on low-platinum group metal (PGM) catalysts, including alloys and core-shell systems, and on non-PGM catalysts. This paper provides an over-view of the issues, approaches, and status of the research. C1 [Payne, T. L.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Payne, TL (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 22 TC 5 Z9 5 U1 1 U2 7 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1081 EP 1092 DI 10.1149/1.2981949 PG 12 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300112 ER PT S AU Liu, DJ Yang, J Kariuki, N Goenaga, G Call, A Myers, D AF Liu, D-J Yang, J. Kariuki, N. Goenaga, G. Call, A. Myers, D. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI PERFORMANCE IMPROVEMENT IN PEMFC USING ALIGNED CARBON NANOTUBES AS ELECTRODE CATALYST SUPPORT SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID REDUCTION; MEMBRANE; OXYGEN; FILM AB A novel membrane electrode assembly (MEA) using aligned carbon nanotabes (ACNT) as the electrocatalyst support was developed for proton exchange membrane fuel cell (PEMFC) application. A multiple-step process of preparing ACNT-PEMFC including ACNT layer growth and catalyzing, MEA fabrication, and single cell packaging is reported. Single cell polarization studies demonstrated improved fuel utilization and higher power density in comparison with the conventional, ink based MEA. C1 [Liu, D-J; Yang, J.; Kariuki, N.; Goenaga, G.; Call, A.; Myers, D.] Argonne Natl Lab, Chem Sci & Engn Div, Argonne, IL 60439 USA. RP Liu, DJ (reprint author), Argonne Natl Lab, Chem Sci & Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM djliu@anl.gov RI Yang, Junbing/E-4316-2010 NR 10 TC 9 Z9 9 U1 1 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1123 EP 1129 DI 10.1149/1.2981954 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300117 ER PT S AU Strmcnik, D van der Vliet, D Lucas, C Karapetrov, G Markovic, NM Stamenkovic, VR AF Strmcnik, Dusan van der Vliet, Dennis Lucas, Chris Karapetrov, Goran Markovic, Nenad M. Stamenkovic, Vojislav R. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Fine Tuning of Activity for Nanoscale Catalysts SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID CO; ELECTRODES; OXIDATION; SPECTROSCOPY; ADSORPTION; SURFACES; COVERAGE; KINETICS; PT(100); PT(111) AB The ability to tune the electronic and structural properties of nanocatalysts can potentially lead towards their superior catalytic activity. This can be achieved by numerous ways such as controlling the size and shape of nanoparticles, the introduction of another metal into the bulk of the catalyst and tuning of the nanoscale surface morphology. The later has been in focus of this report and can be controlled by either preparation procedure or by in-situ electrochemical treatment. C1 [Strmcnik, Dusan; van der Vliet, Dennis; Lucas, Chris; Karapetrov, Goran; Markovic, Nenad M.; Stamenkovic, Vojislav R.] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Strmcnik, D (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI van der Vliet, Dennis/P-2983-2015; Karapetrov, Goran/C-2840-2008; OI van der Vliet, Dennis/0000-0002-2524-527X; Karapetrov, Goran/0000-0003-1113-0137; Lucas, Christopher/0000-0001-5743-3868 NR 19 TC 0 Z9 0 U1 0 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1151 EP 1160 DI 10.1149/1.2981957 PG 10 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300120 ER PT S AU Brosha, EL Rockward, TQT Uribe, FA Garzon, FH AF Brosha, Eric L. Rockward, Tommy Q. T. Uribe, Francisco A. Garzon, Fernando H. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Qualitative Determination of H(2)S Crossover Rates in Nafion (TM) Membranes using Ion-probe Techniques SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID PERFORMANCE; PEMFC AB Polymer electrolyte membrane fuel cells are sensitive to impurities that may be present in either the oxidizer or fuel. H(2)S, even at the ppb level, will have a dramatic and adverse affect on fuel cell performance. The H(2)S permeability through dry and humidified Nafion (TM) PEMFC membranes was studied using ion probe techniques. A sulfide anti-oxidant buffer solution was used to trap and concentrate trace quantities of H(2)S that permeated through 50 cm(2) samples of Nafion (TM) 117 and 212 membranes using a partial pressure difference up to 1030ppm at room temperature. Experiments were conducted for up to 24 hours in order to achieve sulfide ion concentrations high enough to be precisely determined by subsequent titration with Pb(NO(3))(2). The rate of H(2)S crossover for dry 117 and 212 were identical at 1.2e(-7) g/min. Humidification increased the crossover rate to 5.9e(-7) g/min and 1.8e(-6) g/min for 117 and 212 respectively. Although the data collected in this work show that the rate of H(2)S crossover increases with water content and reduced membrane thickness, an accurate determination of permeation constants from this work was not possible because the H(2)S partial pressure was not constant throughout the experiment. C1 [Brosha, Eric L.; Rockward, Tommy Q. T.; Uribe, Francisco A.; Garzon, Fernando H.] Los Alamos Natl Lab, Sensors & Electrochem Devices Grp, Los Alamos, NM 87545 USA. RP Brosha, EL (reprint author), Los Alamos Natl Lab, Sensors & Electrochem Devices Grp, MPA 11, Los Alamos, NM 87545 USA. NR 14 TC 2 Z9 2 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1205 EP 1217 DI 10.1149/1.2981962 PG 13 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300125 ER PT S AU Spendelow, JS Mukundan, R Davey, JR Rockward, T Hussey, DS Jacobson, DL Arif, M Borup, RL AF Spendelow, J. S. Mukundan, R. Davey, J. R. Rockward, T. Hussey, D. S. Jacobson, D. L. Arif, M. Borup, R. L. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI High Resolution Neutron Radiography Imaging of Operating PEM Fuel Cells: Effect of Flow Configuration and Gravity on Water Distribution SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div AB High resolution neutron radiography was used to image polymer electrolyte membrane fuel cells (PEMFCs) during operation under a variety of conditions. The effect of specific operating conditions, including flow direction (co-flow or counter-flow), orientation of the PEMFC with respect to gravity, and simulated anode recycle loop, were examined. Counter-flow operation was found to result in higher water content than co-flow operation, with more uniformly distributed water. Orientation with respect to gravity was also significant, with net water transport observed from the higher side of the cell to the lower side. The higher anode flow rate resulting from the simulated recycle loop facilitated convective removal of liquid water from the anode flow field, leading to lower overall levels of water in the PEMFC. C1 [Spendelow, J. S.; Mukundan, R.; Davey, J. R.; Rockward, T.; Borup, R. L.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Spendelow, JS (reprint author), Los Alamos Natl Lab, MS D429,MPA-11, Los Alamos, NM 87545 USA. OI Mukundan, Rangachary/0000-0002-5679-3930 NR 4 TC 8 Z9 8 U1 1 U2 4 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1345 EP 1355 DI 10.1149/1.2981975 PG 11 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300138 ER PT S AU Ogasawara, H Naslund, LA MacNaughton, JB Anniyev, T Nilsson, A AF Ogasawara, H. Naeslund, L. -A. MacNaughton, J. B. Anniyev, T. Nilsson, A. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Double Role of Water in the Fuel Cell Oxygen Reduction Reaction SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID DENSITY-FUNCTIONAL THEORY; ABSORPTION FINE-STRUCTURE; CORE-LEVEL SPECTROSCOPY; MOLECULAR-OXYGEN; PT(111) SURFACE; O-2; PLATINUM; ADSORPTION; DECOMPOSITION; DISSOCIATION AB Water is present during the normal operating condition of polymer electrolyte membrane fuel cells (PEMFCs) and we have, through model experiments on a platinum surface using x-ray photoelectron spectroscopy, investigated its role in two different stages in the oxygen reduction reaction (ORR). We found that the activation of oxygen to the adsorbed atomic phase occurs readily in the dry region, but not in the humid region process. In this case, water is acting to inhibit the active sites on the catalyst. On the contrary, water is found to promote the reduction of adsorbed atomic oxygen in the formation of a water-hydroxyl surface complex. C1 [Ogasawara, H.; Naeslund, L. -A.; MacNaughton, J. B.; Anniyev, T.; Nilsson, A.] Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. RP Ogasawara, H (reprint author), Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. RI Ogasawara, Hirohito/D-2105-2009 OI Ogasawara, Hirohito/0000-0001-5338-1079 NR 37 TC 9 Z9 9 U1 0 U2 5 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1385 EP 1394 DI 10.1149/1.2981979 PG 10 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300142 ER PT S AU Wang, H Turner, JA AF Wang, Heli Turner, John A. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI SnO(2):F Coated Duplex Stainless Steel for PEM Fuel Cell Bipolar Plates SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div AB Duplex 2205 stainless steel was deposited with similar to 0.6 mu m thick SnO(2):F coating; coated steel was characterized for PEMFC bipolar plate application. Compared with bare alloy, interfacial contact resistance (ICR) values of the coated 2205 steel are higher. SnO(2):F coating adds its own resistance to the air-formed film on the steel. In a PEMFC anode environment, a current peak of ca. 25 mu A/cm(2) registered at ca. 30 min for coated 2205 steel. It stabilized at ca. 2.0 similar to-1.0 mu A/cm(2). This peak is related to the complicated process of coating dissolution and oxide-layer formation. Anodic-cathodic current transfer occurred at ca. 200 min polarization. In a PEMFC cathode environment, current was stable immediately after polarization. The stable current was ca. 0.5 similar to 2.0 mu A/cm(2) during the entire polarization period. AES depth profiles with tested samples and ICP analysis with the tested solutions confirmed the excellent corrosion resistance of the SnO(2):F coated 2205 alloy in simulated PEMFC environments. C1 [Wang, Heli; Turner, John A.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wang, H (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 11 TC 1 Z9 1 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1879 EP 1889 DI 10.1149/1.2982028 PG 11 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300190 ER PT S AU Mukundan, R Davey, JR Lujan, RW Spendelow, JS Kim, YS Hussey, DS Jacobson, DL Arif, M Borup, RL AF Mukundan, Rangachary Davey, John R. Lujan, Roger W. Spendelow, Jacob S. Kim, Yu Seung Hussey, Daniel S. Jacobson, David L. Arif, Muhammad Borup, Rodney L. BE Fuller, T Shinohara, K Ramani, V Shirvanian, P Uchida, H Cleghorn, S Inaba, M Mitsushima, S Strasser, P Nakagawa, H Gasteiger, HA Zawodzinski, T Lamy, C TI Performance and Durability of PEM Fuel Cells Operated at Sub-Freezing Temperatures SO PROTON EXCHANGE MEMBRANE FUEL CELLS 8, PTS 1 AND 2 SE ECS Transactions LA English DT Proceedings Paper CT 8th Symposium on Proton Exchange Membrane Fuel Cells CY OCT, 2008 CL Honolulu, HI SP Electrochem Soc, Electrochem Soc Japan, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochem Div, Electrochem Soc, Battery Div, Electrochem Soc, Ind Electrochem & Electrochem Engn Div ID COLD START; WATER; BEHAVIOR; PEFC AB The effect of MEA preparation on the performance of single-PEM fuel cells operated at sub-freezing temperatures is presented. The cell performance and durability are dependent on the MEA and are probably influenced by the porosity of the catalyst layers. When a cell is operated isothermally at -10 degrees C in constant current mode, the voltage gradually decreases over time and eventually drops to zero. AC impedance analysis indicated that the rate of voltage loss is initially due to an increase in the charge transfer resistance and is gradual. After a period, the rate of decay accelerates rapidly due to mass transport limitations at the catalyst and/or gas diffusion layers. The high frequency resistance also increases over time during the isothermal operation at sub-freezing temperatures and was a function of the initial membrane water content. LANL prepared MEAs showed very little loss in the catalyst surface area with multiple sub-freezing operations, whereas the commercial MEAs exhibited significant loss in cathode surface area with the anode being unaffected. These results indicate that catalyst layer ice formation is influenced strongly by the MEA and is responsible for the long-term degradation of fuel cells operated at sub-freezing temperatures. This ice formation was monitored using neutron radiography and was found to be concentrated near cell edges at the flow field turns. The water distribution also indicated that ice may be forming mainly in the GDLs at -10 degrees C and could be concentrated in the catalyst layer at -20 degrees C. C1 [Mukundan, Rangachary; Davey, John R.; Lujan, Roger W.; Spendelow, Jacob S.; Kim, Yu Seung; Borup, Rodney L.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mukundan, R (reprint author), Los Alamos Natl Lab, MS D429,MPA 11, Los Alamos, NM 87545 USA. OI Mukundan, Rangachary/0000-0002-5679-3930 NR 10 TC 16 Z9 16 U1 0 U2 7 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA SN 1938-5862 BN 978-1-56677-648-6 J9 ECS TRANSACTIONS PY 2008 VL 16 IS 2 BP 1939 EP 1950 DI 10.1149/1.2982034 PG 12 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA BMC67 UT WOS:000271859300196 ER PT S AU Gibson, T Schuchardt, K Stephan, E AF Gibson, Tara Schuchardt, Karen Stephan, Eric BE Freire, J Koop, D Moreau, L TI Application of Provenance for Automated and Research Driven Workflows SO PROVENANCE AND ANNOTATION OF DATA AND PROCESSES SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 2nd International Provenance and Annotation Workshop CY JUN 17-18, 2008 CL Salt Lake City, UT SP Microsoft Corp, Univ Utah, Sci Comp & Imaging Inst, Springer, Univ Utah DE provenance; metadata; use cases; workflow AB Provenance has recently become a popular topic for workflow execution environments but it is also relevant to other applications, such as long-running, user-driven "research workflows", problem solving environments, and data streaming (data analysis) environments. This paper presents a number of use cases where provenance can play an important role in understanding how data was derived, how decisions were made, and enable sharing of data from a variety of sources. We break down the requirements elucidated by our use cases and discuss our experiences in applying an existing provenance system to these use cases. C1 [Gibson, Tara; Schuchardt, Karen; Stephan, Eric] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gibson, T (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM Tara.Gibson@pnl.gov; Karen.Schuchardt@pnl.gov; Eric.Stephan@pnl.gov OI Stephan, Eric/0000-0002-8155-6806 NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-89964-8 J9 LECT NOTES COMPUT SC PY 2008 VL 5272 BP 128 EP 135 PG 8 WC Computer Science, Theory & Methods SC Computer Science GA BIU90 UT WOS:000262977000012 ER PT S AU Santos, E Lins, L Ahrens, JP Freire, J Silva, CT AF Santos, Emanuele Lins, Lauro Ahrens, James P. Freire, Juliana Silva, Claudio T. BE Freire, J Koop, D Moreau, L TI A First Study on Clustering Collections of Workflow Graphs SO PROVENANCE AND ANNOTATION OF DATA AND PROCESSES SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 2nd International Provenance and Annotation Workshop CY JUN 17-18, 2008 CL Salt Lake City, UT SP Microsoft Corp, Univ Utah, Sci Comp & Imaging Inst, Springer, Univ Utah ID SEGMENTATION; SUBGRAPH AB As workflow systems get more widely used, the number of workflows and the volume of provenance they generate has grown considerably. New tools and infrastructure are needed to allow users to interact with, reason about, and re-use this information. In this paper, we explore the use of clustering techniques to organize large collections of workflow and provenance graphs. We propose two different representations for these graphs and present an experimental evaluation, using a collection of 1,700 workflow graphs, where we study the trade-offs of these representations and the effectiveness of alternative clustering techniques. C1 [Santos, Emanuele; Lins, Lauro; Silva, Claudio T.] Univ Utah, Sci Comp & Imaging Inst, Salt Lake City, UT 84112 USA. [Freire, Juliana; Silva, Claudio T.] Univ Utah, Sch Comp, Salt Lake City, UT 84112 USA. [Ahrens, James P.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Santos, E (reprint author), Univ Utah, Sci Comp & Imaging Inst, Salt Lake City, UT 84112 USA. FU Department of Energy SciDAC (VACET and SDM centers); National Science Foundation [IIS-0746500, CNS-0751152, IIS-0713637, OCE-0424602, IIS-0534628, CNS-0514485, IIS-0513692, CNS-0524096, CCF-0401498, OISE-0405402, CCF-0528201, CNS-0551724]; IBM Faculty Awards; CAPES/Fulbright fellowship FX Our research has been funded by the Department of Energy SciDAC (VACET and SDM centers), the National Science Foundation (grants IIS-0746500, CNS-0751152, IIS-0713637, OCE-0424602, IIS-0534628, CNS-0514485, IIS-0513692, CNS-0524096, CCF-0401498, OISE-0405402, CCF-0528201, CNS-0551724), and IBM Faculty Awards (2005, 2006, 2007, and 2008). E. Santos is partially supported by a CAPES/Fulbright fellowship. NR 16 TC 5 Z9 6 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-89964-8 J9 LECT NOTES COMPUT SC PY 2008 VL 5272 BP 160 EP + PG 3 WC Computer Science, Theory & Methods SC Computer Science GA BIU90 UT WOS:000262977000016 ER PT J AU Dunning, JP Hajcak, G Parvaz, MA Maloney, T Alia-Klein, N Woicik, PA Telaug, F Wang, GJ Volkow, ND Goldstein, RZ AF Dunning, Jonathan P. Hajcak, Greg Parvaz, Muhammad A. Maloney, Thomas Alia-Klein, Nelly Woicik, Patricia A. Telaug, Frank Wang, Gelle-Jack Volkow, Nora D. Goldstein, Rita Z. TI Differential electrocortical response to drug stimuli between cocaine addicts and healthy controls SO PSYCHOPHYSIOLOGY LA English DT Meeting Abstract CT 48th Annual Meeting of the Society-for-Psychophysiological-Research CY OCT 01-05, 2008 CL Austin, TX SP Soc Psychophysiol Res C1 [Dunning, Jonathan P.; Hajcak, Greg] SUNY Stony Brook, Stony Brook, NY 11794 USA. [Parvaz, Muhammad A.; Maloney, Thomas; Alia-Klein, Nelly; Woicik, Patricia A.; Telaug, Frank; Wang, Gelle-Jack; Goldstein, Rita Z.] Brookhaven Natl Lab, Upton, NY 11973 USA. [Volkow, Nora D.] Natl Inst Drug Abuse, Bethesda, MD 20892 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL PUBLISHING PI OXFORD PA 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND SN 0048-5772 J9 PSYCHOPHYSIOLOGY JI Psychophysiology PY 2008 VL 45 SU 1 BP S53 EP S53 PG 1 WC Psychology, Biological; Neurosciences; Physiology; Psychology; Psychology, Experimental SC Psychology; Neurosciences & Neurology; Physiology GA 347LX UT WOS:000259144200225 ER PT J AU Murphy, TW Adelberger, EG Battat, JBR Carey, LN Hoyle, CD LeBlanc, P Michelsen, EL Nordtvedt, K Orin, AE Strasburg, JD Stubbs, CW Swanson, HE Williams, E AF Murphy, T. W., Jr. Adelberger, E. G. Battat, J. B. R. Carey, L. N. Hoyle, C. D. LeBlanc, P. Michelsen, E. L. Nordtvedt, K. Orin, A. E. Strasburg, J. D. Stubbs, C. W. Swanson, H. E. Williams, E. TI The apache point observatory lunar laser-ranging operation: Instrument description and first detections SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article ID SUPERNOVAE; GRAVITY AB A next-generation lunar laser-ranging apparatus using the 3.5 m telescope at the Apache Point Observatory in southern New Mexico has begun science operation. The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) has achieved 1 mm range precision to the moon, which should lead to approximately 1 order-of-magnitude improvements in several tests of fundamental properties of gravity. We briefly outline the scientific goals, and then give a detailed discussion of the APOLLO instrumentation. C1 [Murphy, T. W., Jr.; LeBlanc, P.; Michelsen, E. L.; Orin, A. E.; Williams, E.] Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. [Adelberger, E. G.; Swanson, H. E.] Univ Washington, Dept Phys, Seattle, WA 98195 USA. [Battat, J. B. R.] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. [Carey, L. N.] Univ Washington, Dept Astron, Seattle, WA 98195 USA. [Hoyle, C. D.] Humboldt State Univ, Dept Phys & Astron, Arcata, CA 95521 USA. [Nordtvedt, K.] NW Anal, Bozeman, MT USA. [Strasburg, J. D.] Pacific NW Natl Lab, Richland, WA USA. [Stubbs, C. W.] Harvard Univ, Dept Phys, Cambridge, MA 02138 USA. RP Murphy, TW (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. EM tmurphy@physics.ucsd.edu RI Stubbs, Christopher/C-2829-2012 OI Stubbs, Christopher/0000-0003-0347-1724 NR 27 TC 54 Z9 57 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6280 EI 1538-3873 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD JAN PY 2008 VL 120 IS 863 BP 20 EP 37 DI 10.1086/526428 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 256VO UT WOS:000252758200004 ER PT S AU Jones, RE Broesler, R Yu, KM Ager, JW Haller, EE Walukiewicz, W Chen, X Schaff, WJ AF Jones, R. E. Broesler, R. Yu, K. M. Ager, J. W., III Haller, E. E. Walukiewicz, W. Chen, X. Schaff, W. J. GP IEEE TI HIGH EFFICIENCY InAlN-BASED SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID IN1-XGAXN ALLOYS AB The band gap energies of the In1-xAlxN alloys are continuously tunable across the solar spectrum, making them good candidates for high efficiency solar cells. In particular, multijunction solar cells could be fabricated entirely from different compositions of this one alloy system. From modeling experimental measurements of the optical absorption coefficient in alloys with 0 <= x <= 0.6, a band gap bowing parameter of 4.8 +/- 0.5 eV is found for the alloy system. With this number, the alloy compositions for two and three junction tandem cells with maximum theoretical power conversion efficiencies can be determined. Two junction InAlN / Si solar cells are also promising structures for high efficiency solar cells, due to the properties of the interface between n-type InAlN and p-type Si, as well as the band gaps of the respective materials. The theoretical efficiency (detailed balance) for the In0.60Al0.40N / Si tandem cell is 41%. C1 [Jones, R. E.; Broesler, R.; Yu, K. M.; Ager, J. W., III; Haller, E. E.; Walukiewicz, W.] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. [Jones, R. E.; Broesler, R.; Haller, E. E.] Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. [Chen, X.; Schaff, W. J.] Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14853 USA. RP Jones, RE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. FU Director, Office of Science, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, of the U.S. Department of Energy [DE-AC02-05CH11231]; National Defense Science and Engineering FX This work is supported by the Director, Office of Science, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. REJ acknowledges as National Defense Science and Engineering Graduate Fellowship. NR 12 TC 7 Z9 7 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000001 ER PT S AU Wang, D Reese, M Kopidakis, N Gregg, BA AF Wang, Dong Reese, Matthew Kopidakis, Nikos Gregg, Brian A. GP IEEE TI DO THE DEFECTS MAKE IT WORK? DEFECT ENGINEERING IN PI-CONJUGATED POLYMERS AND THEIR SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SEMICONDUCTORS AB The charged defect density in common pi-conjugated polymers such as poly(3-hexylthiophene), P3HT, is around 10(18) cm(-3). Despite, or perhaps because of, this huge defect density, bulk heterojunction solar cells made from these polymers and a C60 derviative such as PCBM exhibit some of the highest efficiencies (similar to 5%) yet obtained in solid state organic photovoltaic cells. We discuss defects in molecular organic semiconductors and in pi-conjugated polymers. These defects can be grouped in two categories, covalent and noncovalent. Somewhat analogous to treating amorphous silicon with hydrogen, we introduce chemical methods to modify the density and charge of the covalent defects in P3HT by treating it with electrophiles such as dimethyl sulfate and nucleophiles such as sodium methoxide. The effects of these treatments on the electrical and photovoltaic properties and stability of organic PV cells is discussed in terms of the change in the number and chemical properties of the defects. Finally, we address the question of whether the efficiency of OPV cells requires the presence of these defects which function as adventitious p-type dopants. Their presence relieves the resistance limitations usually encountered in cleaner organic semiconductors and can create built-in electric fields at junctions. These considerations lead toward the design of a new generation of OPV materials that replaces the covalent defects with purposely added dopants. C1 [Wang, Dong; Reese, Matthew; Kopidakis, Nikos; Gregg, Brian A.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wang, D (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 6 TC 0 Z9 0 U1 1 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 11 EP 13 PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000003 ER PT S AU Gessert, TA Metzger, WK Asher, SE Young, MR Johnston, S Dhere, RG Moriarty, T Duda, A AF Gessert, T. A. Metzger, W. K. Asher, S. E. Young, M. R. Johnston, S. Dhere, R. G. Moriarty, T. Duda, A. GP IEEE TI EFFECTS OF Cu DIFFUSION FROM ZnTe:Cu/Ti CONTACTS ON CARRIER LIFETIME OF CdS/CdTe THIN FILM SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB We study the performance of CdS/CdTe thin film PV devices processed with a ZnTe:Cu/Ti contact to investigate how carrier lifetime (tau) in the CdTe layer is affected by Cu diffusion from the contact. Time-resolved photoluminescence (TRPL) measurements show that T decreases slightly as the contacting temperature increases in the temperature regime that produces "insufficient" Cu concentration in CdTe (similar to room temperature to similar to 250 degrees C). However, T increases significantly once the contact temperature is in the range that yields "optimum" Cu concentration and high-performance devices (similar to 280 to similar to 320 degrees C). At higher substrate temperatures (>similar to 300 degrees C), T drops precipitously, consistent with a region previously identified as producing "excessive" Cu concentration - and poor device performance. The observed T increase within the "optimum temperature" range not only suggests why high-performance devices may form at these contact temperatures using many different contact processes (including paste contacts), but may provide a significant clue as to why Cu-contact formation processes impart a broad latitude in other process parameters. C1 [Gessert, T. A.; Metzger, W. K.; Asher, S. E.; Young, M. R.; Johnston, S.; Dhere, R. G.; Moriarty, T.; Duda, A.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Gessert, TA (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 8 TC 1 Z9 1 U1 1 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 33 EP 37 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000008 ER PT S AU Pern, FJ Noufi, R Li, X DeHart, C To, B AF Pern, F. J. Noufi, R. Li, X. DeHart, C. To, B. GP IEEE TI Damp-Heat Induced Degradation of Transparent Conducting Oxides for Thin-Film Solar Cells SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB The stability of intrinsic and Al-doped single- and bilayer ZnO for thin-film CuInGaSe(2) solar cells, along with Al-doped Zn(1-x)Mg(x)O alloy and Sn-doped In(2)O(3) (ITO) and F-doped SnO(2), was evaluated by direct exposure to damp heat (DH) at 85 degrees C and 85% relative humidity. The results show that the DH-induced degradation rates followed the order of Al-doped ZnO and Zn(1-x)Mg(x)O >> ITO > F:SnO(2). The degradation rates of AI:ZnO were slower for films of higher thickness, higher substrate temperature in sputter-deposition, and with dry-out intervals. As inferred from the optical micro-imaging showing the initiation and propagation of degrading patterns and regions, the degradation behavior appears similar for all TCOs, despite the obvious difference in the degradation rate. A degradation mechanism is proposed to explain the temporal process involving thermal hydrolysis. C1 [Pern, F. J.; Noufi, R.; Li, X.; DeHart, C.; To, B.] Natl Ctr Photovolta, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Pern, FJ (reprint author), Natl Ctr Photovolta, Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 6 TC 4 Z9 5 U1 1 U2 9 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 43 EP 48 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000010 ER PT S AU Wei, SH Li, JB Yan, Y AF Wei, Su-Huai Li, Jingbo Yan, Y. GP IEEE TI DESIGN OF SHALLOW p-TYPE DOPANTS IN ZnO SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Due to the large electronegativity of the oxygen, the ionization energies of acceptors in metal oxides such as ZnO is quite high, making p-type doping a great challenge for the full utilization of ZnO as optoelectronic materials. By analyzing the defect wavefunction characters, we propose several approaches to lower the acceptor ionization energy in ZnO by codoping acceptors with donor or isovalent atoms. We also proposed a universal approach to overcome the doping polarity problem for wide-band-gap semiconductors. This approach can reduce the ionization energies of dopants and the spontaneous compensation from intrinsic defects by effective doping of impurity bands, which can be achieved by introducing passive donor-acceptor complexes or isovalent impurities. The approaches described here for ZnO can be easily extended to other transparent conducting oxides used for solar cell applications. C1 [Wei, Su-Huai; Li, Jingbo; Yan, Y.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wei, SH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 10 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 49 EP 52 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000011 ER PT S AU Duenow, JN Gessert, TA Wood, DM Egaas, B Noufi, R Coutts, TJ AF Duenow, Joel N. Gessert, Timothy A. Wood, David M. Egaas, Brian Noufi, Rommel Coutts, Timothy J. GP IEEE TI ZNO:AL DOPING LEVEL AND HYDROGEN GROWTH AMBIENT EFFECTS ON CIGS SOLAR CELL PERFORMANCE SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID NATIVE POINT-DEFECTS; ZINC-OXIDE; SEMICONDUCTORS; 1ST-PRINCIPLES; FILMS AB Cu(In,Ga)Se-2 (CIGS) photovoltaic (PV) cells require a highly conducting and transparent electrode for optimum device performance. ZnO:Al films grown from targets containing 2.0 wt.% Al2O3 are commonly used for this purpose. Maximum carder mobilities of these films grown at room temperature are similar to 20-25 cm(2)V(-1)s(-1). Therefore, relatively high carrier concentrations are required to achieve the desired conductivity, which leads to free carrier absorption in the near infrared (IR). Lightly doped films (0.05 - 0.2 wt.% Al2O3), which show less IR absorption, reach mobility values greater than 50 cm(2)V(-1)s(-1) when deposited in H-2 partial pressure. We incorporate these lightly doped ZnO:AI layers into CIGS PV cells produced at the National Renewable Energy Laboratory (NREL). Preliminary results show quantum efficiency values of these cells rival those of a past world-record cell produced at NREL that used 2.0 wt.% Al-doped ZnO films. The highest cell efficiency obtained in this trial was 18.1%. C1 [Duenow, Joel N.; Wood, David M.; Egaas, Brian] Colorado Sch Mines, 1500 Illinois St, Golden, CO 80401 USA. [Gessert, Timothy A.; Noufi, Rommel; Coutts, Timothy J.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Duenow, JN (reprint author), Colorado Sch Mines, 1500 Illinois St, Golden, CO 80401 USA. FU U.S.Department of Energy [DE-AC36-99G010337]; NREL [KXEA-3-33607-11, -24] FX This work was supported by the U.S.Department of Energy under Contract No.DE-AC36-99G010337 and NREL subcontracts KXEA-3-33607-11 and-24. NR 22 TC 0 Z9 0 U1 1 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 53 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000012 ER PT S AU Ager, JW Reichertz, LA Yu, KM Schaff, WJ Williamson, TL Hoffbauer, MA Haegel, NM Walukiewicz, W AF Ager, J. W., III Reichertz, L. A. Yu, K. M. Schaff, W. J. Williamson, T. L. Hoffbauer, M. A. Haegel, N. M. Walukiewicz, W. GP IEEE TI InGaN/Si heterojunction tandem solar cells SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID INN; ALLOYS; ALN AB Tandem solar cells using InxGa1-xN heterojunctions with silicon as the active junction were fabricated using gas-source molecular beam epitaxy (MBE) and by a novel deposition method incorporating an energetic nitrogen atom source. N-type InGaN layers were grown on p-Si(l 11) to evaluate predicted low-resistance tunnel junction properties. Ohmic behavior was observed, showing that these junctions can be used to connect the two pn subcells of an InGaN/Si tandem without the requirement of the heavily doped layers used in current multijunction cells. Undoped and Mg-doped films were grown by MBE on n-Si(111) using a AN buffer layer. Depletion is observed on the Si side of the junction and efficiencies approaching 5% were measured for this "hybrid" cell design. Conditions for achieving depletion on the p-InGaN and producing a "single-junction" tandem cell are discussed. C1 [Ager, J. W., III; Reichertz, L. A.; Yu, K. M.; Walukiewicz, W.] Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. [Schaff, W. J.] Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14850 USA. [Williamson, T. L.; Hoffbauer, M. A.] Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87544 USA. [Haegel, N. M.] Naval Postgrad Sch, Monterey, CA 93943 USA. [Walukiewicz, W.] RoseSt Labs Energy, Phoenix, AZ 85034 USA. RP Ager, JW (reprint author), Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. FU Rose Street Energy Laboratory [LB07003462]; U.S. Department of Energy [DE-AC02-05CH11231]; LDRD FX Work at LBNL was supported by Rose Street Energy Laboratory, Contract LB07003462, through the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The LANL work was supported by internal LDRD funding. We thank K. Koester for providing supporting SEM images. NR 11 TC 1 Z9 1 U1 1 U2 7 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 110 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000025 ER PT S AU Chen, X Matthews, KD Hao, D Schaff, WJ Eastman, LF Walukiewicz, W Ager, JW Yu, KM AF Chen, X. Matthews, K. D. Hao, D. Schaff, W. J. Eastman, L. F. Walukiewicz, W. Ager, J. W. Yu, K. M. GP IEEE TI CHARACTERIZATION OF MG-DOPED INGAN AND INALN ALLOYS GROWN BY MBE FOR SOLAR APPLICATIONS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID IN-RICH INGAN; IN1-XGAXN ALLOYS; ENERGY; GAN AB InxGa1-xN and InxAl1-xN alloys are grown via MBE on sapphire substrates. A hole concentration of 7.7x10(17) cm(-3) is achieved on Mg-doped In0.04Ga0.96N. When x>0.11, the Hall samples exhibit strong n-type polarity, whereas p-type polarity is confirmed by hot probe measurement for all Mg-doped InGaN and InAIN samples. Single p-i-n junction solar cells made of the same InxGa1-xN alloy composition are developed. Upon illumination by a 325 nm laser, V-oc is measured at 2.5 V with a fill factor of 61% for all-GaN cell. Clear photo-responses are also observed in InGaN cells with 0.2 and 0.3 Indium content when illuminated by focused outdoor sunlight. C1 [Chen, X.; Matthews, K. D.; Hao, D.; Schaff, W. J.; Eastman, L. F.] Cornell Univ, Sch Elect & Comp Engn, Ithaca, NY 14853 USA. [Walukiewicz, W.; Ager, J. W.; Yu, K. M.] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Chen, X (reprint author), Cornell Univ, Sch Elect & Comp Engn, Ithaca, NY 14853 USA. FU AFOSR through the MURI at Georgia Tech; Phase II SBIR with Structured Materials Inc (SMI); Rosestreet Energy Labs FX This work was supported by AFOSR through the MURI at Georgia Tech and Phase II SBIR with Structured Materials Inc (SMI) and Rosestreet Energy Labs. NR 11 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 122 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000028 ER PT S AU Al-Thani, HA Young, M Asher, S Hasoon, FS AF Al-Thani, Hamda A. Young, Matt Asher, Sally Hasoon, Falah S. GP IEEE TI Microstructure Characterization of Mo Back Contact Used for CIGS Based Solar Cell SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID THIN-FILMS; STRESS; GROWTH AB Two separate series of Mo thin films were deposited on Si/SiO2, and soda lime glass (SLG) substrates using direct-current planar magnetron sputtering, with a sputtering power density of 1.2 W/cm(2). The working gas (Ar) pressure was varied from 0.6 mT to 16 mT to gain a better understanding of the effect of sputtering pressure on the morphology and porosity of the Mo thin films and the subsequent effect on the Na out-diffusion from SLG glass substrates. The morphology of Mo-coated SLG substrates was examined using high-resolution scanning electron microscopy (HRSEM). The porosity of the Mo films as a function of sputtering pressure was studied by transmission electron microscopy (TEM) on Mo-coated Si/SiO2 substrates. Secondary-ion mass spectrometry (SIMS) was applied to depth profile the Na in as-deposited Mo/SLG substrates. C1 [Al-Thani, Hamda A.] Abu Dhabi Water & Elect Author, Natl Energy & Water Res Ctr, POB 54111, Abu Dhabi, U Arab Emirates. [Young, Matt; Asher, Sally; Hasoon, Falah S.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Al-Thani, HA (reprint author), Abu Dhabi Water & Elect Author, Natl Energy & Water Res Ctr, POB 54111, Abu Dhabi, U Arab Emirates. FU U.S. Department of Energy [DE-AC36-99-G010337] FX The authors wish to thank Kim Jones for TEM sample preparation and film characterization, and James Keane and James Dolan for their technical support. This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-99-G010337. NR 11 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 224 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000050 ER PT S AU Hasoon, FS Al-Thani, HA Li, XN Kanevce, A Perkins, C Asher, S AF Hasoon, Falah S. Al-Thani, Hamda A. Li, Xiaonan Kanevce, Ana Perkins, Craig Asher, Sally GP IEEE TI Investigation of the Effect of I-ZnO Window Layer on the Device Performance of the Cd-Free CIGS Based Solar Cells SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID CUINSE2 AB Cu(In,Ga)Se-2 (CIGS) thin films were deposited on Molybdenum coated soda lime glass (SLG/Mo) substrates, using physical vapor deposition (PVD) 3-stage process. The CIGS films were treated by ammonium hydroxide solution before depositing the I-ZnO buffer layer. The I-ZnO layer was deposited using metallorganic chemical vapor deposition (MOCVD) at different substrate temperatures of 200 degrees C, 250 degrees C, and 300 degrees C. The thickness of this buffer layer was varied according to the location of the substrates with respect to the gas flow direction. The CIGS devices were completed by depositing the Al-ZnO window layer by rf magnetron sputtering and applying the Ni/Al front contact grids. The thickness of the I-ZnO buffer layer was measured using a Dek-tak profilometer on soda lime glass substrates which were used as reference samples during the deposition process of I-ZnO buffer layer on CIGS films. Surface depth profiling survey for the elements and their chemical states, as well as their relative concentration was analyzed by X-Ray Photoelectron Spectroscopy (XPS) for as deposited and ammonium hydroxide treated CIGS films. In addition, the performance of the completed CIGS devices was evaluated under standard conditions of 1000 W/m(2) and 25 degrees C. C1 [Hasoon, Falah S.; Li, Xiaonan; Kanevce, Ana; Perkins, Craig; Asher, Sally] Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. [Al-Thani, Hamda A.] Abu Dhabi Water & Elect Author, Natl Energy & Water Res Ctr, Abu Dhabi, U Arab Emirates. RP Hasoon, FS (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. FU U.S. Department of Energy [DE-AC36-99-G010337] FX The authors wish to thank James Keane and James Dolan for their technical support. This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-99-G010337. NR 12 TC 0 Z9 0 U1 0 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 262 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000060 ER PT S AU Li, XN Pankow, J To, B Gessert, T AF Li, Xiaonan Pankow, Joel To, Bobby Gessert, Timothy GP IEEE TI COMPARISON BETWEEN RESEARCH-GRADE AND COMMERCIALLY AVAILABLE SnO(2) FOR THIN-FILM CdTe SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB A comparison between research-grade, tin-oxide (SnO(2)) thin films and those available from commercial sources is performed. The research-grade SnO(2) film is fabricated at NREL by low-pressure metal-organic chemical vapor deposition. The commercial SnO(2) films are Pilkington Tec 8 and Tec 15 fabricated by atmospheric-pressure chemical vapor deposition. Optical, structural, and compositional analyses are performed. From the optical analysis, an estimation of the current losses due to the SnO(2) layer and glass is provided. Our analysis indicates that the optical properties of commercial SnO(2) could be improved for PV usage. C1 [Li, Xiaonan; Pankow, Joel; To, Bobby; Gessert, Timothy] NREL, Golden, CO 80401 USA. RP Li, XN (reprint author), NREL, 1617 Cole Blvd, Golden, CO 80401 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 289 EP 293 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000067 ER PT S AU Teeter, G Asher, S AF Teeter, Glenn Asher, Sally GP IEEE TI MODELING Cu MIGRATION IN CdTe SOLAR CELLS UNDER DEVICE-PROCESSING AND LONG-TERM STABILITY CONDITIONS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID CADMIUM TELLURIDE; DIFFUSION; COPPER; SOLUBILITY; CDS; CRYSTALS; FILMS AB An impurity migration model for systems with material interfaces is applied to Cu migration in CdTe solar cells. In the model, diffusion fluxes are calculated from the Cu chemical potential gradient. Inputs to the model include Cu diffusivities, solubilities, and segregation enthalpies in CdTe, CdS and contact materials. The model yields transient and equilibrium Cu distributions in CdTe devices during device processing and under field-deployed conditions. Preliminary results for Cu migration in CdTe photovoltaic devices using available diffusivity and solubility data from the literature show that Cu segregates in the CdS, a phenomenon that is commonly observed in devices after back-contact processing and/or stress conditions. C1 [Teeter, Glenn; Asher, Sally] NREL, Golden, CO 80401 USA. RP Teeter, G (reprint author), NREL, 1617 Cole Blvd,MS 3218, Golden, CO 80401 USA. NR 27 TC 0 Z9 0 U1 1 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 302 EP 307 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000070 ER PT S AU Gfroerer, TH Simov, PR West, BA Wanlass, MW AF Gfroerer, T. H. Simov, P. R. West, B. A. Wanlass, M. W. GP IEEE TI DEFECT-RELATED TRAPPING AND RECOMBINATION IN METAMORPHIC GaAs0.72P0.28 GROWN ON GaAs SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SEMICONDUCTORS AB Since the bandgap of metamorphic GaAsP can be tuned through a range of energies in a high-radiance region of the solar spectrum, this alloy may be useful in multi-junction solar cells. For this application, achieving high conversion efficiency will require a good understanding of the defects that accompany lattice-mismatch in this system. We use photoluminescence and deep-level transient spectroscopy (DLTS) on GaAs0.72P0.28 to identify defect-related energy levels and assess their impact on photovoltaic device performance. Low temperature photoluminescence spectra reveal a broad defect-related band approximately 0.10 eV below the band-to-band emission. At 165 K and above, thermal activation out of the defect-related band appears to enhance the band-to-band radiative mechanism. DLTS measurements on p-type GaAs0.72P0.28 suggest the presence of a hole trap with a comparable depth (similar to 0.09 eV) and thermal escape temperature, but the collective results are difficult to interpret. An alternative approach assuming a reciprocal rather than logarithmic dependence on time is compelling, but the proposed hopping-transport model will require further testing. C1 [Gfroerer, T. H.; Simov, P. R.; West, B. A.] Davidson Coll, Davidson, NC 28035 USA. [Wanlass, M. W.] Natl Renewable Energy Lab, Golden, CO USA. RP Gfroerer, TH (reprint author), Davidson Coll, Davidson, NC 28035 USA. FU American Chemical Society Petroleum Research Fund FX he authors would like to thank J. J. Carapella for growing the structures and processing the devices. Acknowledgment is made to the Donors of the American Chemical Society Petroleum Research Fund for support of this research. NR 6 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 339 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000079 ER PT S AU Wang, Q Page, MR Iwaniczko, E Xu, YQ Roybal, L Bauer, R To, B Yuan, HC Duda, A Yan, YF AF Wang, Qi Page, M. R. Iwaniczko, E. Xu, Y. Q. Roybal, L. Bauer, R. To, B. Yuan, H. C. Duda, A. Yan, Y. F. GP IEEE TI CRYSTAL SILICON HETEROJUNCTION SOLAR CELLS BY HOT-WIRE CVD SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID OPEN-CIRCUIT VOLTAGE AB Hot-wire chemical vapor deposition (HWCVD) is a promising technique for fabricating Silicon heterojunction (SHJ) solar cells. In this paper we describe our efforts to increase the open circuit voltage (V(oc)) while improving the efficiency of these devices. On p-type c-Si float-zone wafers, we used a double heterojunction structure with an amorphous n/i contact to the top surface and an i/p contact to the back surface to obtain an open circuit voltage (V(oc)) of 679 mV in a 0.9 cm(2) cell with an independently confirmed efficiency of 19.1%. This is the best reported performance for a cell of this configuration. We also made progress on p-type CZ wafers and achieved 18.7% independently confirmed efficiency with little degradation under prolong illumination. Our best Voc for a p-type SHJ cell is 0.688 V, which is close to the 691 mV we achieved for SHJ cells on n-type c-Si wafers. C1 [Wang, Qi; Page, M. R.; Iwaniczko, E.; Xu, Y. Q.; Roybal, L.; Bauer, R.; To, B.; Yuan, H. C.; Duda, A.; Yan, Y. F.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Wang, Q (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 15 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 453 EP 457 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000104 ER PT S AU Yuan, HC Page, MR Iwaniczko, E Xu, YQ Roybal, L Wang, Q Branz, HM Meier, DL AF Yuan, Hao-Chih Page, Matthew R. Iwaniczko, Eugene Xu, Yueqin Roybal, Lorenzo Wang, Qi Branz, Howard M. Meier, Daniel L. GP IEEE TI SILICON SOLAR CELLS WITH FRONT HETERO-CONTACT AND ALUMINUM ALLOY BACK JUNCTION SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB We prototype an alternative n-type monocrystalline silicon (c-Si) solar cell structure that utilizes an n/i-type hydrogenated amorphous silicon (a-Si:H) front hetero-contact and a back p-n junction formed by alloying aluminum (AI) with the n-type Si wafer. Such a structure combines a conventional high-throughput Al-Si alloying process with excellent front surface passivation provided by a-Si:H. A key process consideration is to preserve the clean c-Si front surface through the high-temperature alloying, so there will be effective a-Si:H passivation. From cell simulations, we estimate a front SRV of 10-50 cm/sec has been achieved in our process. The best prototype 1 x 1 cm(2) cell with planar front surface and single anti-reflection (AR) coating layer has demonstrated a confirmed conversion efficiency of 13.5%, V(oc) of 604.7 mV, and fill factor (FF) of 79.9%. Processes for further efficiency improvements are described. C1 [Yuan, Hao-Chih; Page, Matthew R.; Iwaniczko, Eugene; Xu, Yueqin; Roybal, Lorenzo; Wang, Qi; Branz, Howard M.; Meier, Daniel L.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Yuan, HC (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 458 EP 461 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000105 ER PT S AU Geisz, JF Kurtz, SR Wanlass, MW Ward, JS Duda, A Friedman, DJ Olson, JM McMahon, WE Moriarty, TE Kiehl, JT Romero, MJ Norman, AG Jones, KM AF Geisz, J. F. Kurtz, Sarah R. Wanlass, M. W. Ward, J. S. Duda, A. Friedman, D. J. Olson, J. M. McMahon, W. E. Moriarty, T. E. Kiehl, J. T. Romero, M. J. Norman, A. G. Jones, K. M. GP IEEE TI INVERTED GaInP/(In)GaAs/InGaAs TRIPLE-JUNCTION SOLAR CELLS WITH LOW-STRESS METAMORPHIC BOTTOM JUNCTIONS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB We demonstrate high efficiency performance in two ultra-thin, Ge-free III-V semiconductor triple-junction solar cell device designs grown in an inverted configuration. Low-stress metamorphic junctions were engineered to achieve excellent photovoltaic performance with less than 3 x 10(6) cm(-2) threading dislocations. The first design with band gaps of 1.83/1.40/1.00 eV, containing a single metamorphic junction, achieved 33.8% and 39.2% efficiencies under the standard one-sun global spectrum and concentrated direct spectrum at 131 suns, respectively. The second design with band gaps of 1.83/1.34/0.89 eV, containing two metamorphic junctions achieved 33.2% and 40.1% efficiencies under the standard one-sun global spectrum and concentrated direct spectrum at 143 suns, respectively. C1 [Geisz, J. F.; Kurtz, Sarah R.; Wanlass, M. W.; Ward, J. S.; Duda, A.; Friedman, D. J.; Olson, J. M.; McMahon, W. E.; Moriarty, T. E.; Kiehl, J. T.; Romero, M. J.; Norman, A. G.; Jones, K. M.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Geisz, JF (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 15 TC 1 Z9 2 U1 0 U2 8 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 466 EP 470 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000107 ER PT S AU Wang, K Chen, JJ Zhou, WL Zhang, Y Pern, J Yan, YF Mascarenhas, A AF Wang, Kai Chen, Jiajun Zhou, Weilie Zhang, Yong Pern, John Yan, Yanfa Mascarenhas, Angelo GP IEEE TI SYNTHESIS AND PROPERTIES OF TYPE II CORE/SHELL NANOWIRE ARRAYS FOR SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID CDSE QUANTUM DOTS; HETEROSTRUCTURES; NANOCRYSTALS; DEVICES; ENERGY AB This report demonstrates the synthesis and properties of large-area well aligned air-stable ZnO/ZnSe core/shell nanowires on a large area transparent conducting substrate (TCO) by combining chemical vapor deposition (CVD) and pulsed laser deposition (PLD) techniques. the ZnO nanowire were uniformly and perpendicularly grown on the TCO substrate and the ZnSe shell with a thickness of 5-8 nm were epitaxially grown on the ZnO nanowires core. Photoluminescence (PL) studies indicate that the core/shell nanowires are relatively immune to the defects present at the core/shell interface due to the large lattice mismatch. Such a core/shell nanowire array represents a novel architecture that could lead to a stable and efficient as well as low-cost solar cell technology for solar energy harvesting. C1 [Wang, Kai; Chen, Jiajun; Zhou, Weilie] Univ New Orleans, Adv Mat Res Inst, New Orleans, LA 70148 USA. [Zhang, Yong; Pern, John; Yan, Yanfa; Mascarenhas, Angelo] Natl Renewable Energy Lab, Golden, CO USA. RP Wang, K (reprint author), Univ New Orleans, Adv Mat Res Inst, New Orleans, LA 70148 USA. FU DARPA [HR0011-07-1-0032]; Louisiana Board of Regents [LEQSF (2008-11)-RD-B-10]; NREL LDRD; U. S. DOE/OS/BES [DE-AC36-99G010337] FX The work performed at UNO was supported by the DARPA Grant No. HR0011-07-1-0032 and Louisiana Board of Regents Contract No.LEQSF (2008-11)-RD-B-10. The work at NREL was supported by NREL LDRD and U. S. DOE/OS/BES, under contract No. DE-AC36-99G010337. NR 21 TC 0 Z9 0 U1 1 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 509 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000116 ER PT S AU Curtis, CJ van Hest, M Miedaner, A Nekuda, J Hersh, P Leisch, J Ginley, DS AF Curtis, Calvin J. van Hest, Maikel Miedaner, Alex Nekuda, Jennifer Hersh, Peter Leisch, Jennifer Ginley, David S. GP IEEE TI Spray Deposition of High Quality CuInSe2 and CdTe Films SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SOLAR-CELLS AB A number of different ink and deposition approaches have been used for the deposition of CuInSe2 (CIS), Cu(In,Ga)Se-2 (CIGS), and CdTe films. For CIS and CIGS, soluble precursors containing Cu, In, and Ga have been developed and used in two ways to produce CIS films. In the first, In-containing precursor films were sprayed on Mo-coated glass substrates and converted by rapid thermal processing (RTP) to In2Se3. Then a Cu-containing film was sprayed down on top of the In2Se3 and the stacked films were again thermally processed to give CIS. In the second approach, the Cu-, In-, and Ga-containing inks were combined in the proper ratio to produce a mixed Cu-In-Ga ink that was sprayed on substrates and thermally processed to give CIGS films directly. For CdTe deposition, ink consisting of CdTe nanoparticles dispersed in methanol was prepared and used to spray precursor films. Annealing these precursor films in the presence of CdCl2 produced large-grained CdTe films. The films were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). Optimized spray and processing conditions are crucial to obtain dense, crystalline films. C1 [Curtis, Calvin J.; van Hest, Maikel; Miedaner, Alex; Hersh, Peter; Leisch, Jennifer; Ginley, David S.] Natl Renewable Energy Lab, Golden, CO 80401 USA. [Nekuda, Jennifer] Colorada Sch Mines, Golden, CO 80401 USA. RP Curtis, CJ (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. FU U.S. Department of Energy with National Renewable Energy Laboratory [DE-AC36-99GO10337] FX This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-99GO10337 with the National Renewable Energy Laboratory. NR 4 TC 0 Z9 0 U1 0 U2 5 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 519 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000118 ER PT S AU Steiner, MA Geisz, JF Reedy, RC Kurtz, S AF Steiner, Myles A. Geisz, John F. Reedy, Robert C., Jr. Kurtz, Sarah GP IEEE TI A DIRECT COMPARISON OF INVERTED AND NON-INVERTED GROWTHS OF GaInP SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID ALLOYS; GAAS AB The inverted growth of III-V solar cells presents some specific challenges that are not present in regular, non-inverted growths. Because the highly doped top contact layer is grown first, followed by the lengthy high-temperature growth of the remainder of the structure, there is ample time for the dopants in the contact layer to diffuse away. This leads to an increase in the contact resistance to the top layer, and a corresponding drop in voltage. The diffusion of dopants in other layers is similarly altered with respect to the non-inverted configuration because of the change in growth sequence. We compare the dopant profiles of inverted and non-inverted structures by using secondary ion mass spectroscopy and correlate the results with the observed performance of the devices. We also describe a technique for growing a GaInAsN contact layer in the inverted configuration and show that it achieves a specific contact resistance comparable to what is normally observed in non-inverted cells. C1 [Steiner, Myles A.; Geisz, John F.; Reedy, Robert C., Jr.; Kurtz, Sarah] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Steiner, MA (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 7 TC 0 Z9 0 U1 1 U2 5 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 559 EP 564 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000126 ER PT S AU Barnes, TM Blackburn, JL Tenent, RC Morfa, A Heben, M Coutts, TJ AF Barnes, Teresa M. Blackburn, Jeffrey L. Tenent, Robert C. Morfa, Anthony Heben, Michael Coutts, Timothy J. GP IEEE TI OPTIMIZING CARBON NANOTUBE CONTACTS FOR USE IN ORGANIC PHOTOVOLTAICS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SOLAR-CELLS; TRANSPARENT; NETWORKS; FILMS AB Transparent electrical contacts (TCs) play an important role in thin film photovoltaics (PV), including in organic devices (OPV). OPV devices have different TC requirements than traditional thin film devices, due to the need to make them flexible, cost and manufacturing constraints, and the potential benefits that may be realized from using a hole conducting TC. Additionally, the active layer in an OPV device is far thinner than in an inorganic "thin-film" device, causing TC morphology to have a significant effect on device performance. Here, we present data on optimizing carbon nanotube networks for use as TCs in OPV. We look at network deposition techniques and required post-treatment methods along with electrical, optical, and morphological data to devise a fabrication process for a. high quality network that is compatible with OPV device production. C1 [Barnes, Teresa M.; Blackburn, Jeffrey L.; Tenent, Robert C.; Heben, Michael; Coutts, Timothy J.] Natl Renewable Energy Lab, Golden, CO 80401 USA. [Morfa, Anthony] Univ Colorado, Dept Chem, Boulder, CO USA. RP Barnes, TM (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Morfa, Anthony/D-2153-2011 FU U.S. Department of Energy with National Renewable Energy Laboratory [DE-AC36-99GO10337] FX This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-99GO10337 with the National Renewable Energy Laboratory. NR 20 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 624 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000138 ER PT S AU von Roedern, B Ullal, HS AF von Roedern, Bolko Ullal, Harin S. GP IEEE TI "The Role of Polycrystalline Thin-Film PV Technologies in Competitive PV Module Markets" SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB This paper discusses the developments in thin-film PV technologies. It provides an outlook on future commercial module efficiencies achievable based on today's knowledge about champion cell performance. It also provides a relative cost comparison of thin-film and wafer/ribbon based Si PV modules. In 2007, about 65% of the modules produced in the US were thin-film modules when amorphous silicon modules are also considered. C1 [von Roedern, Bolko; Ullal, Harin S.] Natl Ctr Photovolta, Natl Renewable Energy Lab, Golden, CO 80401 USA. RP von Roedern, B (reprint author), Natl Ctr Photovolta, Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 653 EP 656 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000144 ER PT S AU Sang, B Adurodija, F Taylor, M Lim, A Taylor, J Chang, Y McWilliams, S Oswald, R Stanbery, BJ van Hest, M Nekuda, J Miedaner, A Curtis, C Leisch, J Ginley, D AF Sang, B. Adurodija, F. Taylor, M. Lim, A. Taylor, J. Chang, Y. McWilliams, S. Oswald, R. Stanbery, B. J. van Hest, M. Nekuda, J. Miedaner, A. Curtis, C. Leisch, J. Ginley, D. GP IEEE TI LOW COST COPPER INDIUM GALLIUM SELENIDE BY THE FASST (R) PROCESS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Low cost manufacturing of Cu(In,Ga)Se-2 (CIGS) films for high efficiency PV devices by the innovative Field-Assisted Simultaneous Synthesis and Transfer (FASST (R)) process is reported. The FASST (R) process is a two-stage reactive transfer printing method relying on chemical reaction between two separate precursor films to form CIGS, one deposited on the substrate and the other on a printing plate in the first stage. In the second stage these precursors are brought into intimate contact and rapidly reacted under pressure in the presence of an applied electrostatic field. The method utilizes physical mechanisms characteristic of anodic wafer bonding and rapid thermal annealing, effectively creating a sealed micro-reactor that insures high material utilization efficiency, direct control of reaction pressure, and low thermal budget. The use of two independent precursors provides the benefits of independent composition and flexible deposition technique optimization, and eliminates pre-reaction prior to the second stage FASST (R) synthesis of CIGS. High quality CIGS with large grains on the order of several microns are formed in just several minutes based on compositional and structural analysis by XRF, SIMS, SEM and XRD. Cell efficiencies of 12.2% have been achieved using this method. C1 [Sang, B.; Adurodija, F.; Taylor, M.; Lim, A.; Taylor, J.; Chang, Y.; McWilliams, S.; Oswald, R.; Stanbery, B. J.] HelioVolt Corp, 8201 E Riverside Dr,Suite 650, Austin, TX 78744 USA. [van Hest, M.; Nekuda, J.; Miedaner, A.; Curtis, C.; Leisch, J.; Ginley, D.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sang, B (reprint author), HelioVolt Corp, 8201 E Riverside Dr,Suite 650, Austin, TX 78744 USA. NR 7 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 661 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000146 ER PT S AU Kempe, MD Terwilliger, KM Tarrant, D AF Kempe, M. D. Terwilliger, K. M. Tarrant, D. GP IEEE TI STRESS INDUCED DEGRADATION MODES IN CIGS MINI-MODULES SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB The stability of monolithically integrated copper (indium, gallium) (selenium, sulfur) (CIGS) based thin film solar cells on glass were evaluated as a function of highly accelerated stress testing. Mini-modules exposed to high humidity (85 degrees C and 85% RH) had a dominant failure mechanism involving increased resistance in the ZnO:Al transparent conducting oxide. Under Dry heat (85 degrees C and 0% RH) performance loss was much slower and involved the weakening of diodes lowering V-oc and loss of fill factor. These mini-modules were encapsulated using either ethylene vinyl-acetate (EVA) or a Silicone. It was found that encapsulation with EVA led to greater increases in series resistance. These experiments point to the importance of module packaging, transparent conducting oxide stability and cell integration in constructing durable CIGS modules. C1 [Kempe, M. D.; Terwilliger, K. M.] Natl Renewable Energy Lab NREL, 1617 Cole Blvd, Golden, CO 80401 USA. [Tarrant, D.] Shell Solar, Golden, CO 80401 USA. RP Kempe, MD (reprint author), Natl Renewable Energy Lab NREL, 1617 Cole Blvd, Golden, CO 80401 USA. FU U.S. Department of Energy [DE-AC36-99G010337] FX The authors would like to thank Tom McMahon for helping with the infrared imaging and David Albin for help with computer code. This work was carried out under U.S. Department of Energy contract number DE-AC36-99G010337. NR 6 TC 0 Z9 0 U1 0 U2 7 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 670 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000148 ER PT S AU Olsen, LC Gross, ME Kundu, SN AF Olsen, Larry C. Gross, Mark E. Kundu, Sambhu N. GP IEEE TI PROPERTIES OF ENCAPSULATED CIGS CELLS IN 85 degrees C/85%RH SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB This paper concerns studies of encapsulated cells subjected to an environment of 85 degrees C and 85%RH (85/85). Cells are encapsulated with PNNL multi-layer coatings (referred to as PML coatings) utilizing alternating layers of Al2O3, and an advanced polymer. The new polymer has been determined to withstand the 85/85 environment. Two types of cells were used for these studies, namely, SSI mini-modules (which are actually CIGSS devices) and CIGS cells provided by the Institute of Energy Conversion (IEC). Cells were coated and stressed at 85/85 in an environmental chamber. Current-voltage characteristics were acquired before and after coating, and periodically after being subjected to the 85/85 environment. Whereas coated SSI modules were determined to last 1000 hours when stressed at 60 degrees C/90%RH without degradation, the efficiency of these modules degrade to a level of 60% of the beginning-of-life value when stressed at 85/85. Encapsulated IEC cells, however, have exhibited extraordinary results. The efficiency of several encapsulated cells did not decrease for 1500 hours in an 85 degrees C/85%RH environment. This results establishes a benchmark for stressed, encapsulated CIGS cells. C1 [Olsen, Larry C.; Gross, Mark E.; Kundu, Sambhu N.] Pacific Northwest Natl Lab, Richland, WA 99354 USA. RP Olsen, LC (reprint author), Pacific Northwest Natl Lab, Richland, WA 99354 USA. FU NREL FX We wish to acknowledge the support provided by NREL and the technical guidance provided by Dr. Bolko Von Roedern. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 676 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000149 ER PT S AU Keyes, B Symko-Davies, M Mitchell, R Ullal, H von Roedem, B Greene, L Stephens, S AF Keyes, Brian Symko-Davies, Martha Mitchell, Rick Ullal, Harin von Roedem, Bolko Greene, Lori Stephens, Scott GP IEEE TI THE SOLAR AMERICA INITIATIVE (SAI) PV TECHNOLOGY INCUBATOR PROGRAM SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn C1 [Keyes, Brian; Symko-Davies, Martha; Mitchell, Rick; Ullal, Harin; von Roedem, Bolko; Greene, Lori] Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RP Keyes, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. FU U.S. Department of Energy with the National Renewable Energy Laboratory [DE-AC36-99G010337] FX This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-99G010337 with the National Renewable Energy Laboratory NR 0 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 706 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000156 ER PT S AU Moutinho, HR Dhere, RG Romero, MJ Jiang, CS To, B Al-Jassim, MM AF Moutinho, H. R. Dhere, R. G. Romero, M. J. Jiang, C. -S. To, B. Al-Jassim, M. M. GP IEEE TI RECRYSTALLIZATION OF PVD CdTe THIN FILMS INDUCED BY CdCl(2) TREATMENT - A COMPARISON BETWEEN VAPOR AND SOLUTION PROCESSES SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID DIFFRACTION AB The untreated physical-vapor-deposited CdTe films had small grains, with < 111 > texture, and a large concentration of deep levels. For CdCl(2) treatments at moderate temperature/time, there was partial recrystallization, and a moderate decrease in the concentration of deep levels. For the optimal treatment conditions, there was complete recrystallization and grain growth, and further decrease in stress. Electron backscatter diffraction showed that these films had a mixture of small and large grains, many larger than 30 mu m. The larger grains had < 111 > orientation, whereas the smaller grains were randomly oriented, which provided insight on the grain-growth mechanism after recrystallization. There was a significant increase in the cathodoluminescence signal, indicating a decrease in the concentration of deep levels. When performed at the same conditions, the CdCl(2) vapor treatment is more effective in the recrystallization and grain-growth processes than the solution CdCl(2) treatment. All the films had a large concentration of twin boundaries. C1 [Moutinho, H. R.; Dhere, R. G.; Romero, M. J.; Jiang, C. -S.; To, B.; Al-Jassim, M. M.] Natl Renewable Energy Lab, Golden, CO 80127 USA. RP Moutinho, HR (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80127 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 735 EP 739 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000163 ER PT S AU Pinheiro, WA Fernandes, JAS Caboclo, GD To, B Ferreira, CL Quadros, J Cruz, LR AF Pinheiro, W. A. Fernandes, J. A. S. Caboclo, G. D. To, B. Ferreira, C. L. Quadros, J. Cruz, L. R. GP IEEE TI FABRICATION OF TCO/CdS/CdTe/Au SOLAR CELLS USING DIFFERENT CdCl2 TREATMENTS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID CDTE THIN-FILMS AB In this work CdS/CdTe solar cells were submitted to solution, sublimation and vapor CdCl2 treatments, followed by NP etch for several periods of time. The influence of these procedures on cell efficiency is discussed. The individual layers are analyzed and the results are compared with similar studies in the literature. The best NP etching time was 20 s for all CdCl2 treatments. The highest efficiency was achieved for the cell submitted to the solution treatment at 380 degrees C. Although the layers have shown good properties for a high efficiency cell, the maximum overall efficiency was only 7.8%, probably due to high series and low shunt resistances. C1 [Pinheiro, W. A.; Fernandes, J. A. S.; Caboclo, G. D.; Ferreira, C. L.; Quadros, J.; Cruz, L. R.] Inst Mil Engn, Praca Gen Tiburcio 80, BR-22290270 Urca, RJ, Brazil. [To, B.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Pinheiro, WA (reprint author), Inst Mil Engn, Praca Gen Tiburcio 80, BR-22290270 Urca, RJ, Brazil. FU CENPES/Petrobras FX This work was supported by CENPES/Petrobras. The authors thank R. G. Dhere and H. R. Moutinho, from NREL, for helpful discussions. NR 11 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 755 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000167 ER PT S AU Prinja, R Anderson, J Manginell, R Tringe, JW Sopian, K Amin, N Zaidi, SH AF Prinja, Rajiv Anderson, John Manginell, Ron Tringe, J. W. Sopian, K. Amin, Nowshad Zaidi, Saleem H. GP IEEE TI ABSORPTION ENHANCEMENT IN THIN-FILM SILICON SOLAR CELLS IN SOI CONFIGURATION USING PHYSICAL AND GEOMETRICAL OPTICS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID TEMPERATURE; SUBSTRATE AB High performance in crystalline thin (similar to 10 mu m) film silicon solar cells requires complete optical absorption over its spectral range. Geometrical schemes are ineffective due to their large feature dimensions. Enhanced optical absorption can be achieved through two mechanisms based on diffractive and physical optics. In diffractive approach, light confinement is achieved through obliquely propagating transmission orders that effectively fill the frequency space. In the physical optics approach, rigorous coupled wave analysis is used to calculate optical absorption in subwavelength grating structures based on wave guiding mechanism, A 10-mu m thick Si film in SOI configuration was chosen to perform a comparative evaluation of these two approaches. Optical transmission of planar Si films was compared with randomly textured and deeply etched two-dimensional gratings structures. Transmission from random structures was diffuse and translucent, while that from gratings, was weak and wave length-de pendent. Although SOI substrates are not practical for large-scale manufacturing, they have been determined to highly effective for understanding and optimizing optical transmission and device performance. C1 [Prinja, Rajiv; Zaidi, Saleem H.] Gratings Inc, Albuquerque, NM 87107 USA. [Anderson, John; Manginell, Ron] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Tringe, J. W.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Sopian, K.; Amin, Nowshad] Univ Kebangsaan Malaysia, Bangi 43600, Malaysia. RP Prinja, R (reprint author), Gratings Inc, Albuquerque, NM 87107 USA. RI Amin, Nowshad /A-8913-2011; Sopian, Kamaruzzaman/A-3850-2009 OI Sopian, Kamaruzzaman/0000-0002-4675-3927 NR 18 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 876 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000194 ER PT S AU Marion, B AF Marion, B. GP IEEE TI COMPARISON OF PREDICTIVE MODELS FOR PHOTOVOLTAIC MODULE PERFORMANCE SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB This paper examines three models used to estimate the performance of photovoltaic (PV) modules when the irradiances and PV cell temperatures are known. The results presented here were obtained by comparing modeled and measured maximum power (P(m)) for PV modules that rely on different technologies. The models evaluated for estimating P(m) are (1) the power temperature coefficient model, (2) the PVFORM model, and (3) the bilinear interpolation model. These range from simple models with few input parameters to more complex models with more extensive PV module characterization procedures. NREL researchers determined modeling error statistics by comparing model estimates with measured PV performance data. A modification to the power temperature coefficient model was also evaluated that provided improved accuracy. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Marion, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 9 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 943 EP 948 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000209 ER PT S AU Basso, TS AF Basso, Thomas S. GP IEEE TI HIGH-PENETRATION, GRID-CONNECTED PHOTOVOLTAIC TECHNOLOGY CODES AND STANDARDS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB This paper reports the interim status in identifying and reviewing photovoltaic (PV) codes and standards (C&S) and related electrical activities for grid-connected, high-penetration PV systems with a focus on U.S. electric utility distribution grid interconnection. That includes identifying topics and concerns not yet in the scope of existing C&S documents, identifying C&S-related ongoing work and approaches, and providing recommendations related to C&S needs. This paper also addresses certain technical concerns, e.g., monitoring, information exchange, and control pertaining to business models, tariffs, and economics governed by policy and regulatory mandates. However, the policy, regulatory, and business concerns are not this paper's direct focus. Rather, the primary focus is on systems engineering-based C&S technical concerns for high-penetration PV systems in U.S. utility distribution grids. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Basso, TS (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1080 EP 1083 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000237 ER PT S AU Perkins, CL Li, X AF Perkins, C. L. Li, X. GP IEEE TI A Liquid-Phase Quartz Crystal Microbalance for Photovoltaics Research SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID INDIUM TIN OXIDE; SURFACE FUNCTIONALIZATION; CHARGE INJECTION; THIN-FILMS; DEVICES AB Processes involving solid surfaces and liquid reactants are ubiquitous in the semiconductor industry, and photovoltaics is no exception. Examples include the chemical bath deposition of CdS buffer layers in Cu(In,Ga)Se(2) and CuInS(2) devices, a process that is used in virtually every commercially available CIS-based module. Aqueous etching is used for anti-reflective texturizing of silicon cells, and is also used in the cleaning, defect etching, and native oxide removal for that particular PV material. Research on next generation quantum dot-based solar cells frequently uses simple solution-based methods for the growth and modification of the quantum dots. In all of these examples, a liquid is used to remove or deposit very thin, sometimes atomically thin, layers on the surface of a solid, and the nature of the chemical and physical changes that take place at that interface are critical to the proper functioning of the finished photovoltaic device. Despite the widespread use of liquid processes in research and in industry, there are few characterization techniques suitable for in-situ and real-time investigations of the solid-liquid interface. We have recently finished constructing a new, low-cost tool based on a quartz crystal microbalance for investigations of liquid processes that are of interest to the PV community. The tool consists of a liquid-phase QCM, pumps, valving, reaction vessels, membrane contactors for control of dissolved gases, and a PC-based control system, and can be used in continuous flow cell mode or in a batch reaction scheme. Because the system has been integrated with the NREL Surface Analysis Team's cluster tool, films either grown or modified with this new tool can be transferred without fear of atmospheric contamination to a suite of surface analytical techniques for further study. This paper will describe the new tool, its capabilities, potential pitfalls with its use, initial results, and possible future research directions. C1 [Perkins, C. L.; Li, X.] Natl Renewable Energy Lab, Golden, CO 80027 USA. RP Perkins, CL (reprint author), Natl Renewable Energy Lab, Golden, CO 80027 USA. NR 14 TC 0 Z9 0 U1 0 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1122 EP 1126 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000246 ER PT S AU Repins, I Contreras, M Romero, M Yan, YF Metzger, W Li, J Johnston, S Egaas, B DeHart, C Scharf, J McCandless, BE Noufi, R AF Repins, Ingrid Contreras, Miguel Romero, Manuel Yan, Yanfa Metzger, Wyatt Li, Jian Johnston, Steve Egaas, Brian DeHart, Clay Scharf, John McCandless, Brian E. Noufi, Rommel GP IEEE TI CHARACTERIZATION OF 19.9%-EFFICIENT CIGS ABSORBERS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID FILM SOLAR-CELLS; EFFICIENCY AB recently reported a new record total-area efficiency, 19.9%, for CuInGaSe2 (CIGS)-based thin-film solar cells [1]. Current-voltage analysis indicates that improved performance in the record device is due to reduced recombination. The reduced recombination was achieved by terminating the processing with a Ga-poor (In-rich) layer, which has led to a number of devices exceeding the prior (19.5%) efficiency record. This paper documents the properties of the high-efficiency CIGS by a variety of characterization techniques, with an emphasis on identifying near-surface properties associated with the modified processing. C1 [Repins, Ingrid; Contreras, Miguel; Romero, Manuel; Yan, Yanfa; Metzger, Wyatt; Li, Jian; Johnston, Steve; Egaas, Brian; DeHart, Clay; Scharf, John] Natl Renewable Energy Lab, Golden, CO 80401 USA. [McCandless, Brian E.] Inst Energy Convers, Newark, DE 19716 USA. [Noufi, Rommel] Solopower, San Jose, CA 95138 USA. RP Repins, I (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Li, Jian/B-1627-2016 FU U.S. Department of Energy with National Renewable Energy Laboratory [DE-AC36-99GO10337] FX This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-99GO10337 with the National Renewable Energy Laboratory. The authors thank Craig L. Perkins and Bobby To for film composition data, the NREL Device Performance Group for J-V measurements, Falah Hasoon for discussions on film growth, and Tim Gessert and Ramesh Dhere for helpful review. NR 19 TC 5 Z9 6 U1 1 U2 7 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1127 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000247 ER PT S AU Dhere, RG Zhang, Y Romero, MJ Asher, SE Young, M To, B Noufi, R Gessert, TA AF Dhere, R. G. Zhang, Y. Romero, M. J. Asher, S. E. Young, M. To, B. Noufi, R. Gessert, T. A. GP IEEE TI INVESTIGATION OF JUNCTION PROPERTIES OF CdS/CdTe SOLAR CELLS AND THEIR CORRELATION TO DEVICE PROPERTIES SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Secondary-ion mass spectrometry analysis of the CdS/CdTe interface shows that S diffusion in CdTe increases with substrate temperature and CdCl(2) heat treatment. There is also an accumulation of Cl at the interface for CdCl(2)-treated samples. Modulated photo-reflectance studies shows that devices with CdCl(2) heat treatment and open-circuit voltage (V(oc)) of 835 mV have a distinct high electric-field region in the layer with bandgap of 1.45 eV. Electron-beam induced current measurements reveal a one-sided junction for high V(oc) devices. The nature of the junction changes with processing. For heterojunction devices, the depletion region includes the highly defective CdS/CdTe interface, which would increase the recombination current and consequently the dark current, leading to lower V(oc). In the case of CdCl(2)-treated cells, the n(+)-p junction and its high electric-field results in the junction between structurally compatible CdTe and the Te-rich CdSTe alloy, and thus, in higher V(oc). C1 [Dhere, R. G.; Zhang, Y.; Romero, M. J.; Asher, S. E.; Young, M.; To, B.; Noufi, R.; Gessert, T. A.] Natl Renewable Energy Lab, Golden, CO 80127 USA. RP Dhere, RG (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80127 USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1137 EP 1141 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000249 ER PT S AU Lany, S Zunger, A AF Lany, Stephan Zunger, Alex GP IEEE TI LIMITATION OF THE OPEN-CIRCUIT VOLTAGE DUE TO METASTABLE INTRINSIC DEFECTS IN Cu(In,Ga)Se(2) AND STRATEGIES TO AVOID THESE DEFECTS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SOLAR-CELLS AB Using first-principles defect theory, we investigate the role of intrinsic point defects in the limitation of the open-circuit voltage (V(OC)) in Cu(In,Ga)Se(2) solar cells. We find that the intrinsic donors In(Cu) (In-on-Cu antisite defect) and V(Se) (Selenium vacancy) and their defect complexes with V(Cu) (Cu vacancies) represent two independent mechanisms that are expected to cause saturation of V(OC) around 1 eV, when the absorber band gap is increased towards Ga-rich compositions. Strategies to avoid these sources of V(OC) limitation are discussed. C1 [Lany, Stephan; Zunger, Alex] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Lany, S (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 17 TC 0 Z9 0 U1 1 U2 5 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1142 EP 1144 PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000250 ER PT S AU Parikh, VY Wieland, KA Kwon, D Gupta, S Compaan, AD Sambhu, K Olsen, L AF Parikh, Viral Y. Wieland, K. A. Kwon, DoHyoung Gupta, S. Compaan, A. D. Sambhu, Kundu Olsen, Larry GP IEEE TI Thin-Film Tandem Cells with Thin CdTe SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Models using realistic parameters indicate that two-terminal, double-junction tandem solar cells based on CdTe or CuInGaSe2 and related alloys should be able to reach 25% efficiencies.(1) Key to achieving this is high transparency for below-band-gap photons. Cells with transparent back contacts (TBC) and CdTe thickness between 2.4 mu m and 0.3 mu m show over 65% average transmission for photons below bandgap. The short circuit current is not compromised as a 10.6% cell with only 0.5 mu m CdTe is demonstrated with a Jsc of 23.1 mA/cm(2). For the bottom cell we have focused on optimizing HgCdTe, where a single junction efficiency of 6.7% was obtained. Calculations based on the transmission of cells and the quantum efficiency of the best HgCdTe cell indicate that efficiency gains can be made by making the CdTe layer thinner. Finally, a four terminal cell with 7.6% efficiency is discussed. C1 [Parikh, Viral Y.; Wieland, K. A.; Kwon, DoHyoung; Gupta, S.; Compaan, A. D.] Univ Toledo, Dept Phys & Astron, Toledo, OH 43606 USA. [Sambhu, Kundu; Olsen, Larry] Pacific Northwest Natl Lab, Richland, WA USA. RP Parikh, VY (reprint author), Univ Toledo, Dept Phys & Astron, Toledo, OH 43606 USA. FU NREL High Performance PV Prgram FX This work was supported by the NREL High Performance PV Prgram. NR 4 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1145 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000251 ER PT S AU Sheoran, M Kim, DS Rohatgi, A Dekkers, HFW Beaucame, G Young, M Asher, S AF Sheoran, Manav Kim, Dong Seop Rohatgi, Ajeet Dekkers, H. F. W. Beaucame, G. Young, Matthew Asher, Sally GP IEEE TI HYDROGEN DIFFUSION IN SILICON FROM PECVD SILICON NITRIDE SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SOLAR-CELLS; FILMS; SI AB Hydrogen (H) released during the annealing of hydrogenated amorphous silicon nitride (SiNx:H) films diffuses through the crystalline silicon and passivates the defects. This study shows that the stable H isotope deuterium (D), which is released during the annealing of deuterated amorphous silicon nitride (SiNx:H) films, diffuses through the crystalline silicon and is subsequently captured by a thin, highly defective amorphous layer of silicon (a-Si) sputtered on the rear surface. We report on the measurement of the concentration of "penetrated" deuterium (hydrogen), by secondary ion mass spectrometry (SIMS) to monitor the flux of D diffusing through a defect-free single-crystalline silicon wafer. The penetrated D content in the trapping layer increases with the annealing time. However, the flux of D injected into the silicon from the SiNx layer decreases as annealing time increases. At an annealing temperature of 750 degrees C, D was found to penetrate through a 575 mu m thick wafer in as little as 1 second peak annealing time in a Rapid Thermal Processing (RTP) system. Lifetime measurements on defective Si show that higher flux of H during the short RTP anneal is crucial for enhanced hydrogenation of the defects in Si. C1 [Sheoran, Manav; Kim, Dong Seop; Rohatgi, Ajeet] Georgia Inst Technol, Univ Ctr Excellence Photovolta Res & Educ, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. [Young, Matthew; Asher, Sally] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sheoran, M (reprint author), Georgia Inst Technol, Univ Ctr Excellence Photovolta Res & Educ, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1168 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000256 ER PT S AU Jahanshah, F Prinja, R Anderson, J Manginell, R Amin, N Sopian, K Zaidi, SH AF Jahanshah, Fairborz Prinja, Raijiv Anderson, John Manginell, Ron Amin, N. Sopian, K. Zaidi, Saleem H. GP IEEE TI AN INVESTIGATION OF THREE-DIMENSIONAL TEXTURING IN SILICON SOLAR CELLS FOR ENHANCED OPTICAL ABSORPTION SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Application of randomly created sub-wavelength structures using either wet- or dry chemical mechanisms in Si must serve two purposes, i.e., reduces reflection and enhance near IR absorption. This absorption enhancement can only occur through diffractive scattering from random surfaces with feature dimensions of > lambda/n, where n is Si refractive index. For surface features with sizes < lambda/n, no internal diffraction is possible with textured surface behaving like 2 a gradient index film. Absorption enhancement of similar to 4n(2) between two parallel sheets has been predicted using statistical analysis. By creating three-dimensional surfaces with subwavelength textures on front and sidewalls, it may be possible to enhance absorption beyond the 4n(2) statistical limit. We have investigated SILVACO software to carry out a detailed simulation of three-dimensional structured surfaces integrated into conventional solar cell configuration of front and back contacts in p-type substrate using POCl3 diffusion with Al BSF. Simulations have exhibited short-circuit enhancements of similar to 4 mA/cm(2) for two-dimensional and similar to 8 mA/cm(2) for three-dimensional textured surfaces. Solar cells fabricated using p-type substrates with have exhibited short-circuit gain of similar to 7.5 mA/cm(2) for textured surface over a planar surface. Ever superior performance will be achievable following SiN anti-reflection and surface passivation combined with emitter and contact optimization. C1 [Jahanshah, Fairborz; Amin, N.; Sopian, K.] Univ Kebangsaan Malaysia, Bangi, Malaysia. [Prinja, Raijiv; Zaidi, Saleem H.] Gratings Inc, Albuquerque, NM USA. [Anderson, John; Manginell, Ron] Sandia Natl Labs, Albuquerque, NM USA. RP Jahanshah, F (reprint author), Univ Kebangsaan Malaysia, Bangi, Malaysia. RI Amin, Nowshad /A-8913-2011 FU UKM FX Partial funding for this work has been provided by UKM. NR 13 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1313 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000290 ER PT S AU Johnston, SW Berman, GM Ahrenkiel, RK AF Johnston, Steven W. Berman, Gregory M. Ahrenkiel, Richard K. GP IEEE TI MODELING MINORITY-CARRIER LIFETIME TECHNIQUES THAT USE TRANSIENT EXCESS-CARRIER DECAY SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID CONTACTLESS MEASUREMENT; MICROWAVE; SEMICONDUCTORS; DEPENDENCE; WAFERS AB Details of the operation of a photoconductive decay technique called resonant-coupled photoconductive decay are revealed using modeling and circuit simulation. The technique is shown to have a good linear response over its measurement range. Experimentally measured sensitivity and linear response compare well to microwave reflection at low injection levels. We also measure the excess-carrier decay rate by an infrared free-carrier transient absorption technique and show comparable high injection level lifetimes. C1 [Johnston, Steven W.; Berman, Gregory M.; Ahrenkiel, Richard K.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Johnston, SW (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 11 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1318 EP 1323 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000291 ER PT S AU Page, MR Iwaniczko, E Xu, Y Roybal, L Bauer, RE Yuan, HC Wang, Q Meier, DL AF Page, M. R. Iwaniczko, E. Xu, Y. Roybal, L. Bauer, R. E. Yuan, H-C. Wang, Q. Meier, D. L. GP IEEE TI PHOTOCONDUCTIVE DECAY LIFETIME AND SUNS-V(OC) DIAGNOSTICS OF EFFICIENT HETEROJUNCTION SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Minority carrier lifetime and Suns-V(oc) measurements are well-accepted methods for characterization of solar cell devices. We use these methods, with an instrument from Sinton Consulting, as we fabricate and optimize state-of-the-art all hot-wire chemical vapor deposition (HWCVD) silicon heterojunction (SHJ) devices. For double-sided SHJ devices, lifetime measurements were performed immediately after hydrogenated amorphous silicon (a-Si:H) deposition of the front emitter and back base contacts on a Silicon wafer, and also after indium tin oxide (ITO) deposition of transparent conducting oxide contacts. We report results of minority carrier lifetime measurements for double-sided p-type Si heterojunction devices and compare Suns-Voc results to Light I-V measurements on 1-cm(2) solar cell devices measured on an AM1.5 calibrated XT-10 solar simulator. C1 [Page, M. R.; Iwaniczko, E.; Xu, Y.; Roybal, L.; Bauer, R. E.; Yuan, H-C.; Wang, Q.; Meier, D. L.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Page, MR (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 6 TC 0 Z9 0 U1 2 U2 5 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1342 EP 1345 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000296 ER PT S AU Sopori, B Rupnowski, P Appel, J Mehta, V Li, C Johnston, S AF Sopori, Bhushan Rupnowski, Przemyslaw Appel, Jesse Mehta, Vishal Li, Chuan Johnston, Steve GP IEEE TI WAFER PREPARATION AND IODINE-ETHANOL PASSIVATION PROCEDURE FOR REPRODUCIBLE MINORITY-CARRIER LIFETIME MEASUREMENT SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SILICON AB We have determined that mechanisms of irreproducibility in measurement of lifetime arise from two sources: (i) improper wafer cleaning, and (ii) instability of I-E solution when in contact with a Si wafer. This paper describes a sequential optical oxidation and chemical cleaning procedure that can reproducibly yield the correct values of bulk lifetime. We have observed that surface passivation is optically activated, which often causes an initial increase in the measured lifetime. This initial activation time can be greatly reduced by exposing the wafer in the bag to higher intensity light such as a solar simulator for 5-10 minutes. This procedure yields reproducible, very low recombination surfaces, suitable for measuring t(b) as high as 2 ms. We will discuss why this cleaning procedure is necessary and propose mechanism of instability in the passivation of I-E/Si. C1 [Sopori, Bhushan; Rupnowski, Przemyslaw; Appel, Jesse; Mehta, Vishal; Li, Chuan; Johnston, Steve] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Sopori, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 7 TC 0 Z9 0 U1 1 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1364 EP 1367 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000301 ER PT S AU Reese, MO Morfa, AJ White, MS Kopidakis, N Shaheen, SE Rumbles, G Ginley, DS AF Reese, Matthew O. Morfa, Anthony J. White, Matthew S. Kopidakis, Nikos Shaheen, Sean E. Rumbles, Garry Ginley, David S. GP IEEE TI Short-term Metal/Organic Interface Stability Investigations of Organic Photovoltaic Devices SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID POLYMER SOLAR-CELLS; DEGRADATION; ATMOSPHERE AB As organic photovoltaic (OPV) devices have begun to move toward initial applications, issues of their stability are becoming increasingly important. The de facto standard OPV devices are made from a blend of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM), and these serve as a test bed for lifetime testing. Delamination, oxidation, and chemical interactions at the metal electrode/organic interface have been posited as degradation pathways in organic electronic devices.[1,21 Here, two short-term experiments were employed to evaluate the stability of this interface in the light and dark. Full devices and unprotected organic surfaces were separately examined, and both were found to be stable in air over the Course of 10's of minutes while in the dark. While unprotected devices were stable (less than 20% loss in efficiency) in air for 100 minutes under constant 1-sun illumination, unprotected organic surfaces were not, and good devices could not be made on them subsequently. C1 [Reese, Matthew O.; Morfa, Anthony J.; White, Matthew S.; Kopidakis, Nikos; Shaheen, Sean E.; Rumbles, Garry; Ginley, David S.] NREL, Golden, CO 80401 USA. RP Reese, MO (reprint author), NREL, 1617 Cole Blvd, Golden, CO 80401 USA. RI Morfa, Anthony/D-2153-2011; White, Matthew/B-3405-2013; Shaheen, Sean/M-7893-2013 OI White, Matthew/0000-0001-6719-790X; NR 10 TC 0 Z9 0 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1491 EP 1493 PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000329 ER PT S AU Yan, YF Jiang, CS Wu, XZ Noufi, R Wei, SH Al-Jassim, MM AF Yan, Yanfa Jiang, C. S. Wu, X. Z. Noufi, R. Wei, S. -H. Al-Jassim, M. M. GP IEEE TI GRAIN-BOUNDARY PHYSICS IN POLYCRYSTALLINE PHOTOVOLTAIC MATERIALS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SOLAR-CELLS; PSEUDOPOTENTIALS; SILICON; FILMS AB We use the combination of high-resolution electron microscopy and density-functional theory to study the atomic structure and electronic effects of grain boundaries in polycrystalline photovoltaic materials such as Si, CdTe, CuInSe(2), and CuGaSe(2). We find that grain boundaries containing dislocation cores create deep levels in Si, CdTe, and CuGaSe(2). Surprisingly, however, they do not create deep levels in CuInSe(2). We further find that the presence of Ga in grain boundaries in CuInSe(2) generates deep levels. These results may explain the fact that Si and CdTe solar cells usually require special passivation, whereas CuInSe(2) solar cells do not. The passivation of grain boundaries in Si and CdTe is also studied. We find that grain boundaries in CdTe can be passivated very well by Cl, Br, and I. C1 [Yan, Yanfa; Jiang, C. S.; Wu, X. Z.; Noufi, R.; Wei, S. -H.; Al-Jassim, M. M.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Yan, YF (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 13 TC 0 Z9 0 U1 1 U2 6 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1513 EP 1516 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000334 ER PT S AU Bar, M Weinhardt, L Pookpanratana, S Heske, C Nishiwaki, S Shafarman, WN Fuchs, O Blum, M Yang, W Denlinger, JD AF Bar, M. Weinhardt, L. Pookpanratana, S. Heske, C. Nishiwaki, S. Shafarman, W. N. Fuchs, O. Blum, M. Yang, W. Denlinger, J. D. GP IEEE TI BAND GAP ENERGY OF CHALCOPYRITE THIN FILM SOLAR CELL ABSORBERS DETERMINED BY SOFT X-RAY EMISSION AND ABSORPTION SPECTROSCOPY SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID ELECTRICAL-PROPERTIES; HETEROJUNCTION; CU(IN,GA)SE-2; ALIGNMENT; CUIN3SE5; CUGA5SE8; CUINSE2; IMPACT AB The chemical and electronic structure of high-efficiency chalcopyrite thin film solar cell absorbers significantly differs between the surface and the bulk. While it is widely accepted that the absorber surface exhibits a Cu-poor surface phase with increased band gap (E-g), a direct access to the crucial information of the depth-dependency of Eg is still missing. In this paper, we demonstrate that a combination of x-ray emission and absorption spectroscopy allows a determination of Eg in the surface-near bulk and thus complements the established surface- and bulk-sensitive techniques of Eg determination. As an example, we discuss the determination of Eg for a Cu(In,Ga)Se-2 absorber and find a value of (1.52 +/- 0.20) eV. C1 [Bar, M.; Weinhardt, L.; Pookpanratana, S.; Heske, C.] Univ Nevada, Dept Chem, 4505 Maryland Pkwy, Las Vegas, NV 89154 USA. [Nishiwaki, S.; Shafarman, W. N.] Univ Delaware, Inst Energy Convers IEC, Newark, DE 19716 USA. [Fuchs, O.; Blum, M.] Univ Wurzburg, Expt Phys II, D-97074 Wurzburg, Germany. [Yang, W.; Denlinger, J. D.] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Adv Light Source ALS, Berkeley, CA 94720 USA. RP Bar, M (reprint author), Univ Nevada, Dept Chem, 4505 Maryland Pkwy, Las Vegas, NV 89154 USA. RI Weinhardt, Lothar/G-1689-2013 FU National Renewable Energy Laboratory [XXL-5-44205-12, ADJ-1-30630-12]; Deutsche Forschungsgemeinschaft (DFG) within the Emmy-Noether-Programm FX We acknowledge funding by the National Renewable Energy Laboratory under subcontract XXL-5-44205-12 and ADJ-1-30630-12. M.B. is grateful for sponsorship by the Deutsche Forschungsgemeinschaft (DFG) within the Emmy-Noether-Programm. NR 21 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1523 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000336 ER PT S AU Barnett, A Wang, XT Waite, N Murcia, P Honsberg, C Kirkpatrick, D Laubacher, D Kiamilev, F Goossen, K Wanlass, M Steiner, M Schwartz, R Gray, J Gray, A Sharps, P Emery, K Kazmerski, L AF Barnett, Allen Wang, Xiaoting Waite, Nick Murcia, Paola Honsberg, Christiana Kirkpatrick, Doug Laubacher, Dan Kiamilev, Fouad Goossen, Keith Wanlass, Mark Steiner, Myles Schwartz, Richard Gray, Jeff Gray, Allen Sharps, Paul Emery, Keith Kazmerski, Larry GP IEEE TI INITIAL TEST BED FOR VERY HIGH EFFICIENCY SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Very High Efficiency Solar Cell (VHESC) program is developing integrated optical system-photovoltaic modules for portable applications that operate at greater than 50 percent efficiency. We are integrating the optical design with the solar cell design, and we have entered previously unoccupied design space [1]. A test bed for rapid development and verification of performance of subsystems is also being developed. The results and analysis of the first complete integrated optics and solar cells on this test bed are reported. The demonstration has achieved efficiency greater than 36%. Analysis shows a direct path to efficiencies greater than 40%. These initial results have not been verified by NREL or any other 3(rd) party. We have previously reported the sum of the solar cell efficiencies to be over 42%, and optical subsystem efficiency greater than 93% [2]. Our approach is driven by proven quantitative models for the solar cell design, the optical design and the integration of the two. C1 [Barnett, Allen; Wang, Xiaoting; Waite, Nick; Murcia, Paola; Honsberg, Christiana; Kiamilev, Fouad; Goossen, Keith] Univ Delaware, Newark, DE 19716 USA. [Kirkpatrick, Doug] DARPA, Arlington, VA 22203 USA. [Laubacher, Dan] EI Pont Nemours & Co, Wilmington, DE 19805 USA. [Wanlass, Mark; Steiner, Myles; Emery, Keith; Kazmerski, Larry] NREL, Golden, CO 80401 USA. [Schwartz, Richard; Gray, Jeff] Purdue Univ, W Lafayette, IN 47907 USA. [Gray, Allen; Sharps, Paul] EMCORE, Albuquerque, NM 87123 USA. RP Barnett, A (reprint author), Univ Delaware, Newark, DE 19716 USA. FU U.S. Government Defense Advanced Research Projects Agency [HR0011-0709-0005] FX This research was, in part, funded by the U.S. Government Defense Advanced Research Projects Agency under Agreement No.: HR0011-0709-0005. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either express or implied, of the U.S. Government. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1563 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000344 ER PT S AU Young, DL Egaas, B Pinegar, S Stradins, P AF Young, David L. Egaas, Brian Pinegar, Scott Stradins, Paul GP IEEE TI A NEW REAL-TIME QUANTUM EFFICIENCY MEASUREMENT SYSTEM SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB We have developed a new technique for measuring the quantum efficiency (QE) in solar cells in real-time using a unique, electronically controlled, full-spectrum light source. Full-spectrum QE graphs can be obtained in less than one second (as opposed to 20 minutes using traditional QE instruments). The high measurement speed is achieved by parallel processing of information from a multitude of spectral channels encoded in modulation frequency bands. The reduction in time scale makes this QE measurement technique compatible with inline production diagnostics, high-fidelity, spectral-matching cell binning, and thin-film module spatial spectral response uniformity tests. The instrument is completely solid-state with no moving parts, is robust enough for manufacturing environments, and is significantly less expensive than a traditional QE instrument. C1 [Young, David L.; Egaas, Brian; Pinegar, Scott; Stradins, Paul] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Young, DL (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 4 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1612 EP 1614 PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000354 ER PT S AU Fraas, LM Avery, JE Huang, HX Minkin, L Fraas, JX Maxey, LC Gehl, A AF Fraas, L. M. Avery, J. E. Huang, H. X. Minkin, L. Fraas, J. X. Maxey, L. C. Gehl, A. GP IEEE TI FIELD EXPERIENCE WITH 3-SUN MIRROR MODULE SYSTEMS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB JX Crystals' 3-sun PV mirror modules have now been operating in four separate systems in the field for up to 2 years. Two post-mounted 2-axis tracking arrays of 12 modules each were installed at the Shanghai Flower Park in April of 2006. Then 672 modules were installed in a 100 kW array on N-S horizontal beam trackers at the Shanghai Flower Port in November of 2006. Finally, sets of 4 modules were installed on azimuth-tracking carousels on buildings at the Oak Ridge National Lab and at the U. of Nevada in Las Vegas in late 2007. All of these modules in each of these systems are still operating at their initial power ratings. No degradation in performance has been observed. The benefit of these 3-sun PV mirror modules is that they use 1/3 of the silicon single-crystal cell material in comparison to traditional planar modules. Since aluminum mirrors are much cheaper than high-purity single-crystal silicon-cells, these modules and systems should be much lower in cost when manufactured in high volume. C1 [Fraas, L. M.; Avery, J. E.; Huang, H. X.; Minkin, L.; Fraas, J. X.] JX Crystals Inc, Issaquah, WA 98027 USA. [Maxey, L. C.; Gehl, A.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Fraas, LM (reprint author), JX Crystals Inc, Issaquah, WA 98027 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1618 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000356 ER PT S AU Kempe, MD AF Kempe, Michael D. GP IEEE TI ACCELERATED UV TEST METHODS AND SELECTION CRITERIA FOR ENCAPSULANTS OF PHOTOVOLTAIC MODULES SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Photovoltaic modules are exposed to extremely harsh conditions of heat, humidity, high voltage, mechanical stress, thermal cycling and ultraviolet (UV) radiation. The current qualification tests (e.g. IEC 61215) do not require UV exposure high enough to evaluate a 20(+) year lifespan. Methods to quickly test the UV durability of photovoltaic materials are needed. In considering encapsulant materials, the initial performance and material cost are important but the ability to maintain adhesion and transmissivity under UV exposure are equally important. This can be evaluated under highly accelerated conditions with light from a xenon arc lamp using glass that transmits more UV radiation than standard cerium doped glass. The use of highly transmissive glass results in an effective UV dose that is about 3.8 times higher with regard to adhesion. With this configuration a UV dose equivalent to 20 years of exposure can be obtained in just over 6 months using standard commercial accelerated stress chambers. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kempe, MD (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 14 TC 1 Z9 1 U1 0 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1701 EP 1706 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000375 ER PT S AU del Cueto, JA Rummel, S Kroposki, B Osterwald, C Anderberg, A AF del Cueto, J. A. Rummel, S. Kroposki, B. Osterwald, C. Anderberg, A. GP IEEE TI STABILITY OF CIS/CIGS MODULES AT THE OUTDOOR TEST FACILITY OVER TWO DECADES SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID FILM SOLAR-CELLS; DAMP HEAT AB We examine the status and question of long-term stability of copper indium diselenide (CIS) photovoltaic (PV) module performance for numerous modules that are deployed in the array field, or on the roof of, the outdoor test facility (OTF) at NREL, acquired from two manufacturers. Performance is characterized with current-voltage (I-V) measurements obtained either at standard test conditions (STC) or under real-time monitoring conditions, taken over the course of many years. We present and scrutinize I-V characteristics for degradation modes. Analysis yields that CIS PV modules can exhibit either moderate (2% to 4% per year) to negligible or small (less than 1% per year) degradation rates, and that the predominant loss mode appears to be fill factor diminution, often associated with increases in the series resistance in some of the modules. A secondary mode of degradation observed comprises metastable changes to the open-circuit voltage. The featured modules are deployed on three separate testbeds. C1 [del Cueto, J. A.; Rummel, S.; Kroposki, B.; Osterwald, C.; Anderberg, A.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP del Cueto, JA (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 8 TC 1 Z9 1 U1 1 U2 6 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1707 EP 1712 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000376 ER PT S AU Ruther, R del Cueto, J Tamizh-Mani, G Montenegro, AA Rummel, S Anderberg, A von Roedern, B AF Ruther, R. del Cueto, J. Tamizh-Mani, G. Montenegro, A. A. Rummel, S. Anderberg, A. von Roedern, B. GP IEEE TI PERFORMANCE TEST OF AMORPHOUS SILICON MODULES IN DIFFERENT CLIMATES - YEAR FOUR: PROGRESS IN UNDERSTANDING EXPOSURE HISTORY STABILIZATION EFFECTS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB In a round robin outdoor exposure experiment carried out in three different climates, we have previously demonstrated that amorphous silicon (a-Si) PV modules reach higher stabilized performance levels in warmer climates. The four-year experiment involved three identical sets of thin-film a-Si modules from various manufacturers deployed outdoors simultaneously in three sites with distinct climates. Each PV module set spent a one-year period at each site before a final period at the original site where it was first deployed. The experiment aimed to determine the light-induced degradation and stabilization characteristics of a-Si regarding specific history of exposure, and to compare degradation rates in different climates. We propose that after the initial sharp degradation associated with the Stabler-Wronski effect (SWE) has passed, the subsequent stabilized performance levels attained will depend largely on light exposure and a characteristic temperature associated within a coherent time-scale. PV modules which were first deployed at the lowest-temperature site for one year, reaching a stabilized state, and were then further deployed at higher temperature sites for two more years, experienced considerable recovery in output parameters (Pmax and FF). However, when further deployed back at the original, lowest-temperature site, performance degraded back to the first year, original level. C1 [Ruther, R.; Montenegro, A. A.] Univ Fed Santa Catarina, LABSOLAR Lab Energia Solar, Caixa Postal 476, BR-88040900 Florianopolis, SC, Brazil. [Ruther, R.] Univ Fed Santa Catarina, LabEEE Lab Eficiencia Energet Edificacoes, BR-88040900 Florianopolis, SC, Brazil. [del Cueto, J.; Rummel, S.; Anderberg, A.; von Roedern, B.] Natl Renewable Energy Lab, Thin Film Partnership, Golden, CO 80401 USA. [Tamizh-Mani, G.] Arizona State Univ East, Photovolta Testing Lab, Mesa, AZ 85212 USA. RP Ruther, R (reprint author), Univ Fed Santa Catarina, LABSOLAR Lab Energia Solar, Caixa Postal 476, BR-88040900 Florianopolis, SC, Brazil. EM ruther@mbox1.ufsc.br; Joseph_DelCueto@nrel.gov; manit@asu.edu NR 12 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1713 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000377 ER PT S AU Metzger, WK Levi, DH AF Metzger, Wyatt K. Levi, Dean H. GP IEEE TI DEVICE PHYSICS OF NANOSCALE INTERDIGITATED SOLAR CELLS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID PHOTOVOLTAIC DEVICES AB Recently there has been theoretical and experimental evidence for the formation of nanodomains in polycrystalline Cu(In,Ga)Se(2) that may form complex three-dimensional intertwined p-n networks. This has caused some researchers to consider such a network as the operative method of current collection in Cu(In,Ga)Se(2) solar cells. Quantitative modeling is required to test this assumption and evaluate the relevant physics. This paper uses multidimensional device simulation to explore the physics and solar cell performance of interdigitated p-n junctions for material parameters relevant to the postulated conditions. The physics at the nanoscale are often not intuitive, but the results indicate that interdigitated junctions can improve solar cell performance relative to corresponding planar-junction devices and achieve reasonably high solar cell efficiencies with semiconductor materials that have less than optimal electro-optical properties. C1 [Metzger, Wyatt K.; Levi, Dean H.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Metzger, WK (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 15 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1726 EP 1730 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000380 ER PT S AU Perkins, J Berry, J van Hest, M Alleman, J Dabney, M Gedvilas, L Ginley, DS Leenheer, A O'Hayre, R AF Perkins, John Berry, Joseph van Hest, Maikel Alleman, Jeff Dabney, Matthew Gedvilas, Lynn Ginley, David S. Leenheer, Andrew O'Hayre, Ryan GP IEEE TI OPTIMIZATION OF CONDUCTIVITY AND TRANSPARENCY IN AMORPHOUS IN-ZN-O TRANSPARENT CONDUCTORS SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID THIN-FILMS AB Amorphous mixed metal oxide TCOs are of increasing interest due to the excellent opto-electronic properties and smoothness (R-RMS < 0.5 nm) obtained for sputtered films deposited at less than 100 degrees C. In particular, for amorphous In-Zn-O (a-IZO) films grown from a ceramic target with 10 wt. % ZnO in In2O3, the current industry standard, conductivities sigma >= 2500 S/cm are common. Here, we have investigated the combined materials phase space of oxygen stoichiometry and metals composition (In:Zn ratio) and made two key discoveries. First, that high conductivity a-IZO thin films can be made with substantially less indium provided that a corresponding change is also made in the oxygen content. And second, that for all compositions of a-IZO, the electron mobility (mu) and carrier concentration (N) fall on a single common curve when plotted as mu vs N. C1 [Perkins, John; Berry, Joseph; van Hest, Maikel; Alleman, Jeff; Dabney, Matthew; Gedvilas, Lynn; Ginley, David S.] Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. [Leenheer, Andrew; O'Hayre, Ryan] Colorado Sch Mines, Golden, CO 80401 USA. RP Perkins, J (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI O'Hayre, Ryan/A-8183-2009 FU U.S. Department of Energy [DE-AC36-99G010337]; National Renewable Energy Laboratory FX This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-99G010337 with the National Renewable Energy Laboratory. NR 5 TC 0 Z9 0 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1734 EP + PG 2 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000382 ER PT S AU Rupnowski, P Sopori, B AF Rupnowski, Przemyslaw Sopori, Bhushan GP IEEE TI STRENGTH OF SI WAFERS WITH MICROCRACKS: A THEORETICAL MODEL SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn ID SILICON AB Wafer breakage is a major problem in the photovoltaic industry and becomes more serious as the industry attempts to use thinner wafers. It is well established that the poor strength of PV wafers is primarily due to the presence of residual microcracks, which are generated by cutting and wafering procedures and are not removed by subsequent etching of the wafers. This paper addresses fracture mechanics modeling of the strength of silicon PV wafers. We are showing that the surface damage, which includes the subsurface microcracks, determines the ultimate strength of the PV wafers. The modeling of PV wafers consists of Monte Carlo simulations and finite-element analysis that is supported by the fracture energy theory for curved cracks. As an example, a virtual experiment on a statistical set of 100 wafers subjected to uniaxial tension is performed. The predicted strength distribution is shown to match well with the experimental results available in the literature. C1 [Rupnowski, Przemyslaw; Sopori, Bhushan] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Rupnowski, P (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1801 EP 1804 PG 4 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000397 ER PT S AU van Hest, MFAM Curtis, CJ Miedaner, A Pasquarelli, RM Kaydanova, T Hersh, P Ginley, DS AF van Hest, Maikel F. A. M. Curtis, Calvin J. Miedaner, Alex Pasquarelli, Robert M. Kaydanova, Tanya Hersh, Peter Ginley, David S. GP IEEE TI DIRECT-WRITE CONTACTS: METALLIZATION AND CONTACT FORMATION SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Using direct-write approaches in photovoltaics for metallization and contact formation can significantly reduce the cost per waft of producing photovoltaic devices. Inks have been developed for various materials, such as Ag, Cu, Ni and Al, which can be used to inkjet print metallizations for various kinds of photovoltaic devices. Use of these inks results in metallization with resistivities close to those of bulk materials. By means of inkjet printing a metallization grid can be printed with better resolution, i.e. smaller lines, than screen-printing. Also inks have been developed to deposit transparent conductive oxide films by means of ultrasonic spraying. C1 [van Hest, Maikel F. A. M.; Curtis, Calvin J.; Miedaner, Alex; Pasquarelli, Robert M.; Kaydanova, Tanya; Hersh, Peter; Ginley, David S.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP van Hest, MFAM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 5 TC 0 Z9 0 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1809 EP 1811 PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000399 ER PT S AU Coddington, MH AF Coddington, Michael H. GP IEEE TI EVALUATING THE RATIONALE FOR THE UTILITY-ACCESSIBLE EXTERNAL DISCONNECT SWITCH SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB The utility-accessible alternating current (AC) external disconnect switch (EDS) for distributed generators, including photovoltaic (PV) systems, is a hardware feature that allows a utility's employees to manually disconnect a customer-owned generator from the electricity grid. Proponents of the EDS contend that it is necessary to keep utility line workers safe when they make repairs to the electric distribution system. Opponents assert it is a redundant feature that adds cost without providing tangible benefits. In this paper, we examine the utility-accessible EDS debate in the context of utility-interactive PV systems for residential and small commercial installations. We also evaluate the rationale for EDS requirements. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Coddington, MH (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 10 TC 0 Z9 0 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 1930 EP 1934 PG 5 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000425 ER PT S AU Granata, JE Merrill, J AF Granata, J. E. Merrill, J. GP IEEE TI MASS AND COST COMPARISON OF LIGHTWEIGHT ARRAY AND RIGID ARRAY STRUCTURES SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB Lightweight solar array structures continue to be developed to take advantage of the mass savings afforded by thin-film photovoltaic (TFPV) and thin crystalline multijunction (MJ) technologies currently under development. A comparison of one such lightweight array concept to a state of the practice rigid array concept using state of the practice, TFPV, and next-generation thin MJ solar cells is presented. The results demonstrate that lightweight arrays with TFPV technology can provide advantages in cost and mass savings over state of the practice rigid solar array technology, particularly in high radiation orbits and should be considered in the trade space for future space power systems. C1 [Granata, J. E.] Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. [Granata, J. E.] Aerosp Corp, Albuquerque, NM USA. [Merrill, J.] US Air Force, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM USA. RP Granata, JE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 2052 EP + PG 3 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000451 ER PT S AU Cameron, CP Boyson, WE Riley, DM AF Cameron, Christopher P. Boyson, William E. Riley, Daniel M. GP IEEE TI COMPARISON OF PV SYSTEM PERFORMANCE-MODEL PREDICTIONS WITH MEASURED PV SYSTEM PERFORMANCE SO PVSC: 2008 33RD IEEE PHOTOVOLTAIC SPECIALISTS CONFERENCE, VOLS 1-4 SE IEEE Photovoltaic Specialists Conference LA English DT Proceedings Paper CT 33rd IEEE Photovoltaic Specialists Conference CY MAY 11-16, 2008 CL San Diego, CA SP IEEE, Elect Devices Soc, Inst Elect & Elect Engn AB The U.S. Department of Energy has supported development of the Solar Advisor Model (SAM) to provide a common platform for evaluation of the solar energy technologies being developed with the support of the Department. This report describes a detailed comparison of performance-model calculations within SAM to actual measured PV system performance in order to evaluate the ability of the models to accurately predict PV system energy production. This was accomplished by using measured meteorological and irradiance data as an input to the models, and then comparing model predictions of solar and PV system parameters to measured values from co-located PV arrays. The submodels within SAM which were examined include four radiation models, three module performance models, and an inverter model. The PVWATTS and PVMod models were also evaluated. C1 [Cameron, Christopher P.; Boyson, William E.; Riley, Daniel M.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Cameron, CP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 1 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0160-8371 BN 978-1-4244-1640-0 J9 IEEE PHOT SPEC CONF PY 2008 BP 2099 EP 2104 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Energy & Fuels; Engineering; Materials Science GA BMZ70 UT WOS:000273995000460 ER PT S AU Lombardini, M Deiterding, R Pullin, DI AF Lombardini, Manuel Deiterding, Ralf Pullin, D. I. BE Meyers, J Geurts, BJ Sagaut, P TI Large Eddy Simulations of the Richtmyer-Meshkov Instability in a Converging Geometry SO QUALITY AND RELIABILITY OF LARGE-EDDY SIMULATIONS SE ERCOFTAC Series LA English DT Proceedings Paper CT 1st Meeting on Quality and Reliability of Large-Eddy Simulation CY OCT 22-24, 2007 CL Leuven, BELGIUM SP COST, LESAID, European Res Community Flow, Turbulence & Combust, Res Fdn Flanders DE Large-eddy simulations (LES) with strong shocks; Richtmyer-Meshkov instability (RMI); Compressible turbulent mixing; Adaptive mesh refinement (AMR) ID COMPRESSIBLE TURBULENCE; MODEL; SHOCKS; SCALAR; FLOWS AB This work presents on-going research on large-eddy simulations of shock-generated mixing ill Richtmyer-Meshkov flow ill converging geometries. A hybrid numerical method is used oil each subgrid of the mesh hierarchy, within the AMROC (adaptive mesh refinement object oriented C++) framework: it is a shock capturing method but; reverts to a centered scheme with low numerical viscosity ill regions of smoother flow. The stretched-vortex subgrid-scale model allows for the capturing of the small-scale mixing, process between the two fluids. Results presented focus on the evolution of the mixing layer and its internal statistics including various spectra and p.d.f.s of mixed molar and mass fractions. A detailed quantitative analysis has also been conducted including space-time histories of instantaneous cylindrical shellaveragesse quantities, taken concentrically to the main shocks. Comparisons are made with the planar Richtmyer-Meshkov instability with reshock studied by Vetter and Sturtevant (1995) [1] and Hill et al. (2006) [2]. C1 [Lombardini, Manuel; Pullin, D. I.] CALTECH, Grad Aeronaut Labs, Pasadena, CA 91125 USA. [Deiterding, Ralf] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Lombardini, M (reprint author), CALTECH, Grad Aeronaut Labs, Pasadena, CA 91125 USA. EM manuel@caltech.edu RI Deiterding, Ralf/A-3394-2009; sagaut, pierre/M-3880-2014 OI Deiterding, Ralf/0000-0003-4776-8183; sagaut, pierre/0000-0002-3785-120X FU ASC program of the Department of Energy of DoE [B341492, W-7405-ENG-48] FX The authors would like to acknowledge the helpful conversations with D.J.Hill. This work is supported by the ASC program of the Department of Energy under subcontract no. B341492 of DoE contract W-7405-ENG-48. NR 17 TC 2 Z9 2 U1 1 U2 4 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1382-4309 BN 978-1-4020-8577-2 J9 ERCOFTAC SER PY 2008 VL 12 BP 283 EP + PG 2 WC Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BIT09 UT WOS:000262480100023 ER PT S AU Lu, ZM Zhang, DX Chen, Y AF Lu, Zhiming Zhang, Dougxiao Chen, Yan BE Cai, X Yeh, TCJ TI Information Fusion using the Kalman Filter based on Karhunen-Loeve Decomposition SO QUANTITATIVE INFORMATION FUSION FOR HYDROLOGICAL SCIENCES SE Studies in Computational Intelligence LA English DT Article; Book Chapter ID GROUNDWATER INVERSE PROBLEM; DATA ASSIMILATION; STEADY-STATE; PARAMETER-IDENTIFICATION; GEOSTATISTICAL APPROACH; POROUS-MEDIA; FLOW; TRANSMISSIVITY; TRANSIENT; SIMULATIONS C1 [Lu, Zhiming] Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. [Chen, Yan] Univ Oklahoma, Mewbourne Sch Petr & Geol Engn, Norman, OK 73019 USA. [Zhang, Dougxiao] Univ So Calif, Dept Civil & Environm Engn, Los Angeles, CA 90089 USA. [Zhang, Dougxiao] Univ So Calif, Mork Family Dept Chem Engn & Mat Sci, Los Angeles, CA 90089 USA. RP Lu, ZM (reprint author), Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. EM zhiming@lanl.gov; donzhang@usc.edu; yan@ou.edu RI Zhang, Dongxiao/D-5289-2009; OI Zhang, Dongxiao/0000-0001-6930-5994; Lu, Zhiming/0000-0001-5800-3368 NR 41 TC 0 Z9 0 U1 1 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 1860-949X BN 978-3-540-75383-4 J9 STUD COMPUT INTELL PY 2008 VL 79 BP 43 EP 68 D2 10.1007/978-3-540-75384-1 PG 26 WC Computer Science, Interdisciplinary Applications; Mathematics, Applied; Water Resources SC Computer Science; Mathematics; Water Resources GA BJK85 UT WOS:000266724200003 ER PT S AU Vasco, DW AF Vasco, D. W. BE Cai, X Yeh, TCJ TI Trajectory-Based Methods for Modeling and Characterization SO QUANTITATIVE INFORMATION FUSION FOR HYDROLOGICAL SCIENCES SE Studies in Computational Intelligence LA English DT Article; Book Chapter ID POROUS-MEDIA; SOLUTE TRANSPORT; PARAMETER-IDENTIFICATION; SATURATION; PRESSURE; FLOW; ADSORPTION; SIMULATION; EQUATIONS; STRESS C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Vasco, DW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM dwvasco@lbl.gov RI Vasco, Donald/G-3696-2015 OI Vasco, Donald/0000-0003-1210-8628 NR 59 TC 1 Z9 1 U1 1 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 1860-949X BN 978-3-540-75383-4 J9 STUD COMPUT INTELL PY 2008 VL 79 BP 69 EP 103 D2 10.1007/978-3-540-75384-1 PG 35 WC Computer Science, Interdisciplinary Applications; Mathematics, Applied; Water Resources SC Computer Science; Mathematics; Water Resources GA BJK85 UT WOS:000266724200004 ER PT S AU Evans, PG Bennink, RS Grice, WP AF Evans, P. G. Bennink, R. S. Grice, W. P. BE Meyers, RE Shih, Y Deacon, KS TI Modeling Resonant Cavities for Single-Photon Waveguide Sources SO QUANTUM COMMUNICATIONS AND QUANTUM IMAGING VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Quantum Communications and Quantum Imaging VI CY AUG 12-14, 2008 CL San Diego, CA DE PPKTP waveguide; waveguide cavity; Bragg gratings; SPDC ID KTIOPO4; KTP AB Spectral correlations between photon pairs generated by spontaneous parametric down conversion (SPDC) in bulk non-linear optical crystals remain a hindrance to the implementation of efficient quantum communication architectures. It has been demonstrated that SPDC within a distributed micro-cavity can result in little or no correlation between photon pairs. We present results oil modeling three different cavity configurations based oil integrated Bragg gratings. Output from the SPDC process can be tailored by altering the periodicity and geometry of such nanostructures. We will discuss the merits of each cavity configuration from the standpoint of degenerate type-II SPDC. C1 [Evans, P. G.; Bennink, R. S.; Grice, W. P.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Evans, PG (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM evanspg@ornl.gov RI Grice, Warren/L-8466-2013; OI Grice, Warren/0000-0003-4266-4692 NR 13 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7312-7 J9 P SOC PHOTO-OPT INS PY 2008 VL 7092 AR 709202 DI 10.1117/12.795232 PG 8 WC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology; Telecommunications SC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology; Telecommunications GA BIQ87 UT WOS:000262082200001 ER PT S AU Grice, WP Bennink, RS Zhao, Z Meyer, K Whitten, W Shaw, R AF Grice, W. P. Bennink, R. S. Zhao, Z. Meyer, K. Whitten, W. Shaw, R. BE Meyers, RE Shih, Y Deacon, KS TI Spectral and spatial effects in spontaneous parametric down-conversion with a focused pump SO QUANTUM COMMUNICATIONS AND QUANTUM IMAGING VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Quantum Communications and Quantum Imaging VI CY AUG 12-14, 2008 CL San Diego, CA DE Entanglement; down-conversion; quantum optics; photon ID QUANTUM; INTERFERENCE; PHOTON AB Photons produced in the process of spontaneous parametric down-con version (SPDC) are typically entangled in multiple degrees of freedom. Although polarization is often the parameter of interest, the presence of spectral or spatial entanglement can complicate experiments, either by reducing the visibility of certain interference effects or by reducing collection efficiency. Several recent works have shown that the collection efficiency can be improved by focusing the pump beam. This approach has the added benefit of: increasing the bandwidths of the emitted photons. We show that, in the case of type II SPDC, a focused pump can result in different spatial profiles for the signal and idler. If the crystal is configured for emission of polarization-entangled photon pairs, this effect will reduce the fidelity of that entanglement. Moreover, this spatial asymmetry leads to different spectral profiles for the two photons, even when the pump is monochromatic. The spectral and spatial asymmetries can be attributed to the difference in the angular dispersion (walk-off) of the two polarizations, along with a strong correlation between wavelength and emission direction. We also examine the link between spatial entanglement and single-mode coupling efficiency. We find that efficiency is maximized when spatial entanglement can be eliminated. For the case in which walk-off does not play a role, this can be accomplished by properly focusing the pump. C1 [Grice, W. P.; Bennink, R. S.; Zhao, Z.] Oak Ridge Natl Lab, Computat Sci & Engn Div, Oak Ridge, TN USA. RP Grice, WP (reprint author), Oak Ridge Natl Lab, Computat Sci & Engn Div, Oak Ridge, TN USA. EM gricew@ornl.gov RI Grice, Warren/L-8466-2013; OI Grice, Warren/0000-0003-4266-4692 NR 18 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7312-7 J9 P SOC PHOTO-OPT INS PY 2008 VL 7092 AR 70920Q DI 10.1117/12.795102 PG 11 WC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology; Telecommunications SC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology; Telecommunications GA BIQ87 UT WOS:000262082200014 ER PT S AU Humble, TS Bennink, RS Grice, WP AF Humble, Travis S. Bennink, Ryan S. Grice, Warren P. BE Meyers, RE Shih, Y Deacon, KS TI Total teleportation of a single-photon state SO QUANTUM COMMUNICATIONS AND QUANTUM IMAGING VI SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Quantum Communications and Quantum Imaging VI CY AUG 12-14, 2008 CL San Diego, CA DE Quantum teleportation; quantum optics; Bell-state measurement; quantum entanglement ID QUANTUM TELEPORTATION AB Recent demonstrations of teleportation have transferred quantum information encoded into either polarization or field-quadrature degrees of freedom (DOFs), but an outstanding question is how to simultaneously teleport quantum information encoded into multiple DOFs. We describe how the transverse-spatial, spectral and polarization states of a single photon can be simultaneously teleported using a pair of multimode, polarization-entangled photons derived from spontaneous parametric down-conversion. Furthermore, when the initial photon pair is maximally entangled in the spatial, spectral, and polarization DOFs then the photon's full quantum state can be reliably teleported using a Bell-state measurement based on sum-frequency generation. C1 [Humble, Travis S.; Bennink, Ryan S.; Grice, Warren P.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Humble, TS (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM humblets@ornl.gov RI Grice, Warren/L-8466-2013; OI Grice, Warren/0000-0003-4266-4692 NR 11 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7312-7 J9 PROC SPIE PY 2008 VL 7092 AR 70920V DI 10.1117/12.795091 PG 9 WC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology; Telecommunications SC Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology; Telecommunications GA BIQ87 UT WOS:000262082200017 ER PT S AU Seamons, JA Carroll, MS AF Seamons, J. A. Carroll, M. S. BE Donkor, EJ Pirich, AR Brandt, HE TI High bit rate germanium single photon detectors for 1310 nm - art. no. 697607 SO QUANTUM INFORMATION AND COMPUTATION VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Quantum Information and Computation VI CY MAR 19-20, 2008 CL Orlando, FL SP SPIE DE SPAD; APD; photo detectors; photodiodes telecommunications; dark counts; sensors; 1.3mum ID PHOTODIODES AB There is increasing interest in development of high speed, low noise and readily fieldable near infrared (NIR) single photon detectors. InGaAs/InP Avalanche photodiodes (APD) operated in Geiger mode (GM) are a leading choice for NIR due to their preeminence in optical networking. After-pulsing is, however, a primary challenge to operating InGaAs/InP single photon detectors at high frequencies'. After-pulsing is the effect of charge being released from traps that trigger false ("dark") counts. To overcome this problem, hold-off times between detection windows are used to allow the traps to discharge to suppress after-pulsing. The hold-off time represents, however, an upper limit on detection frequency that shows degradation beginning at frequencies of similar to 100 kHz in InGaAs/InP. Alternatively, germanium (Ge) single photon avalanche photodiodes (SPAD) have been reported to have more than an order of magnitude smaller charge trap densities than InGaAs/InP SPADs(2), which allowed them to be successfully operated with passive quenching 2 (i.e., no gated hold off times necessary), which is not possible with InGaAs/InP SPADs, indicating a much weaker dark count dependence on hold-off time consistent with fewer charge traps. Despite these encouraging results suggesting a possible higher operating frequency limit for Ge SPADs, little has been reported on Ge SPAD performance at high frequencies presumably because previous work with Ge SPADs has been discouraged by a strong demand to work at 1550 nm. NIR SPADs require cooling, which in the case of Ge SPADs dramatically reduces the quantum efficiency of the Ge at 15 5 0 run. Recently, however, advantages to working at 13 10 rim have been suggested which combined with a need to increase quantum bit rates for quantum key distribution (QKD) motivates examination of Ge detectors performance at very high detection rates where InGaAs/InP does not perform as well. Presented in this paper are measurements of a commercially available Ge APD operated at relatively short GM hold-off times to examine whether there are potential advantages to using Ge for 13 10 nm single photon detection. A weaker after-pulsing dependence on frequency is observed offering initial indications of the potential that Ge APDs might provide better high frequency performance. C1 [Seamons, J. A.; Carroll, M. S.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Seamons, JA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 11 TC 1 Z9 1 U1 1 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7167-3 J9 P SOC PHOTO-OPT INS PY 2008 VL 6976 BP 97607 EP 97607 DI 10.1117/12.778125 PG 7 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Multidisciplinary SC Computer Science; Mathematics; Physics GA BIC17 UT WOS:000258327300003 ER PT S AU Zapf, VS AF Zapf, Vivien S. BE Barbara, B Imry, Y Sawatzky, G Stamp, PCE TI A review of Bose-Einstein Condensation in certain quantum magnets containing Cu and Ni SO QUANTUM MAGNETISM SE NATO Science for Peace and Security Series B - Physics and Biophysics LA English DT Proceedings Paper CT Pacific-Institute-of-Theoretical-Physics Summer School on Quantum Magnetism CY JUN, 2006 CL Les Houches, FRANCE SP Pacific Inst Theoret Phys AB We summarize a set of recent experimental and theoretical work on the phenomenon of Bose-Einstein Condensation (BEC) of magnetic degrees of freedom in quantum magnets. We will focus on two examples: BaCuSi2O6, which contains planes of Cu S = 1/2 dimers, and NiCl2-4SC(NH2)(2) (DTN), an organic magnet with Ni S = 1 weakly-coupled chains. In both compounds, the BEC corresponds to a field-induced antiferromagnetic ordered state that persists over a magnetic field range H-c1 to H-c2. At the quantum critical point at H-c1 the predicted power-law behavior of the critical fields and the magnetization for 3-D BEC is observed at low temperatures. In addition, BaCuSi2O6 shows a dimensional crossover from a 3-D BEC to 2-D behavior below 1 K. C1 Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM USA. RP Zapf, VS (reprint author), Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM USA. RI Zapf, Vivien/K-5645-2013 OI Zapf, Vivien/0000-0002-8375-4515 NR 17 TC 0 Z9 0 U1 1 U2 9 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1871-465X BN 978-1-4020-8510-9 J9 NATO SCIENCE PEACE S PY 2008 BP 239 EP 249 DI 10.1007/978-1-4020-8512-3_15 PG 11 WC Physics, Applied SC Physics GA BIA14 UT WOS:000257881600015 ER PT J AU Refsnider, KA Laabs, BJC Plummer, MA Mickelson, DM Singer, BS Caffee, MW AF Refsnider, Kurt A. Laabs, Benjamin J. C. Plummer, Mitchell A. Mickelson, David M. Singer, Bradley S. Caffee, Marc W. TI Last glacial maximum climate inferences from cosmogenic dating and glacier modeling of the western Uinta ice field, Uinta Mountains, Utah SO QUATERNARY RESEARCH LA English DT Article DE Uinta Mountains; last glacial maximum; cosmogenic nuclide; CRN; glacier modeling; ice field; Lake Bonneville; glacial geology; paleoclimate ID EQUILIBRIUM-LINE ALTITUDES; PRODUCTION-RATES; BONNEVILLE BASIN; LAKE BONNEVILLE; NORTH-AMERICA; USA; COLORADO; BE-10; MORAINES; PINEDALE AB During the last glacial maximum (LGM), the western Uinta Mountains of northeastern Utah were occupied by the Western Uinta Ice Field. Cosmogenic Be-10 surface-exposure ages from the terminal moraine in the North Fork Provo Valley and paired Al-26 and Be-10 ages from striated bedrock at Bald Mountain Pass set limits on the timing of the local LGM. Moraine boulder ages suggest that ice reached its maximum extent by 17.4 +/- 0.5 ka (+/- 2 sigma). Be-10 and Al-26 measurements on striated bedrock from Bald Mountain Pass, situated near the former center of the ice field, yield a mean Al-26/Be-10 ratio of 5.7 +/- 0.8 and a mean exposure age of 14.0 +/- 0.5 ka, which places a minimum-limiting age on when the ice field melted completely. We also applied a mass/energy-balance and ice-flow model to investigate the LGM climate of the western Uinta Mountains. Results suggest that temperatures were likely 5 to 7 degrees C cooler than present and precipitation was 2 to 3.5 times greater than modern, and the western-most glaciers in the range generally received more precipitation when expanding to their maximum extent than glaciers farther east. This scenario is consistent with the hypothesis that precipitation in the western Uintas was enhanced by pluvial Lake Bonneville during the last glaciation. (C) 2007 University of Washington. All rights reserved. C1 [Refsnider, Kurt A.; Mickelson, David M.; Singer, Bradley S.] Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA. [Laabs, Benjamin J. C.] SUNY Coll Geneseo, Dept Geol Sci, Geneseo, NY 14454 USA. [Plummer, Mitchell A.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. [Caffee, Marc W.] Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. RP Refsnider, KA (reprint author), Inst Arctic & Alpine Res, 1560 30th St,450 UCB, Boulder, CO 80303 USA. EM kurt.refsnider@colorado.edu RI Singer, Bradley/F-4991-2012; Caffee, Marc/K-7025-2015; OI Singer, Bradley/0000-0003-3595-5168; Caffee, Marc/0000-0002-6846-8967; Laabs, Benjamin/0000-0001-8825-2672 NR 59 TC 27 Z9 27 U1 2 U2 6 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0033-5894 J9 QUATERNARY RES JI Quat. Res. PD JAN PY 2008 VL 69 IS 1 BP 130 EP 144 DI 10.1016/j.yqres.2007.10.014 PG 15 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 258JZ UT WOS:000252865500013 ER PT S AU Doerry, AW AF Doerry, A. W. BE Ranney, KI Doerry, WD TI SAR data collection and processing requirements for high quality Coherent Change Detection - art. no. 694706 SO RADIO SENSOR TECHNOLOGY XII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Radio Sensor Technology XII CY MAR 18-19, 2008 CL Orlando, FL DE SAR; radar; image; change detection; CCD AB Coherent Change Detection (CCD) is a technique for observing very subtle changes between two Synthetic Aperture Radar (SAR) images. It is an Interferometric processing technique that measures the coherence between two images, and denotes 'change' where coherence is not observed, and 'no change' where coherence is observed. Consequently, the strategy must be to form both images with as much initial coherence as possible, and then see where in spite of our best efforts coherence cannot be achieved. Many things contribute to destroying coherence, but we want to eliminate all sources except for temporal change in the scene being imaged itself. This requires that a number of variables in the data collection be well controlled, and that the processing must be adapted to mitigate the effects of residual imperfections to achieve maximum coherence. It must be emphasized that the coherence calculation, that is, calculating the actual CCD product from two images is the easy part. The hard part is making sure that the two input images have the underlying characteristics to yield a quality result. The purpose of this paper is to discuss "What it takes to get good CCD results". C1 [Doerry, A. W.] Sandia Natl Labs, Livermore, CA 94550 USA. RP Doerry, AW (reprint author), POB 5800,MS 1330, Albuquerque, NM 87185 USA. NR 15 TC 6 Z9 6 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7138-3 J9 P SOC PHOTO-OPT INS PY 2008 VL 6947 BP 94706 EP 94706 DI 10.1117/12.775609 PG 12 WC Telecommunications SC Telecommunications GA BHW86 UT WOS:000257109300003 ER PT S AU Dickey, FM Doerry, AW AF Dickey, F. M. Doerry, A. W. BE Ranney, KI Doerry, WD TI Recovering shape from shadows in synthetic aperture radar imagery SO RADIO SENSOR TECHNOLOGY XII SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Radio Sensor Technology XII CY MAR 18-19, 2008 CL Orlando, FL DE SAR; radar; image; shadows; shape; 3D ID SEGMENTATION; OBJECTS AB There has been little interest in the information associated with the shadows in high resolution Synthetic Aperture Radar (SAR) images. In this paper we give an algorithm for the reconstruction of an object's shape from the shadows cast by the object in a sequence of SAR images. The algorithm is a back-projection type algorithm based on the intersection of solids. The effects of diffraction and synthetic aperture occlusion on SAR shadow resolution are also addressed. C1 [Dickey, F. M.; Doerry, A. W.] Sandia Natl Labs, Livermore, CA 94550 USA. RP Dickey, FM (reprint author), POB 5800,MS 0311, Albuquerque, NM 87185 USA. EM fmdicke@sandia.gov; awdoerr@sandia.gov NR 24 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7138-3 J9 PROC SPIE PY 2008 VL 6947 AR 694707 DI 10.1117/12.775610 PG 12 WC Telecommunications SC Telecommunications GA BHW86 UT WOS:000257109300004 ER PT J AU Castanha, C Trumbore, S Amundson, R AF Castanha, Cristina Trumbore, Susan Amundson, Ronald TI Methods of separating soil carbon pools affect the chemistry and turnover time of isolated fractions SO RADIOCARBON LA English DT Article ID ORGANIC-MATTER; DENSITY FRACTIONATION; NMR-SPECTROSCOPY; TROPICAL SOILS; RADIOCARBON; DYNAMICS; FOREST; CALIFORNIA; STABILIZATION; NITROGEN AB A variety of physical and chemical techniques are used to fractionate soil organic matter, but detailed comparisons of the different approaches and tests of how separation methods influence the properties of isolated organic matter pools are lacking. In this case study based on A horizon samples of 2 California coniferous forests soils, we 1) evaluate the effects of root removal and ultrasonic dispersion on the properties of the <2 g cm(-3) light fraction and 2) compare the properties of fractions obtained by sequential density separations of ultrasonically treated soil with those obtained by density followed by acid/base hydrolysis (Trumbore et al. 1996). A root-removal effort based on hand-picking visible roots reduced the radiocarbon content and increased the estimated turnover time of the light fraction by roughly 12%. Root-removal protocols that vary between investigators thus can potentially confound variability in carbon cycling for this fraction caused by environmental factors, such as climate. Ultrasonic dispersion did not have a clear effect on the light fraction C and N content or isotopic signature, but led to a decrease in the % C and C/N of the recovered heavy fractions, and losses of 12-19% of the total soil C to the sodium metatungstate density solution. Sequentially isolated density fractions clearly differed in mineralogy and organic matter chemistry, but natural-abundance (14)C analyses indicated that distinct mineral phases did not correspond to unique C-turnover pools. Density fractions containing kaolinite group minerals alone and in combination with hydroxy-interlayered vermiculite were found to harbor both fast and slow cycling carbon. In contrast, severe chemical treatment isolated a carbon pool with the lowest overall (14)C content and longest inferred mean turnover time. Overall, our results show that care must be taken when relying on physical (density) separation to isolate soil fractions with different dynamics, as the details of treatment will influence the results. C1 [Castanha, Cristina] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Trumbore, Susan] Univ Calif Irvine, Phys Sci Res Facil, Irvine, CA 92697 USA. [Amundson, Ronald] Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Castanha, C (reprint author), Lawrence Berkeley Natl Lab, 1 Cyclotron Rd,Mail Stop 70A-4418, Berkeley, CA 94720 USA. EM ccastanha@lbl.gov RI Trumbore, Susan/B-1948-2013; Amundson, Ronald /E-2654-2015; Castanha, Cristina/D-3247-2015 OI Castanha, Cristina/0000-0001-7327-5169 NR 52 TC 19 Z9 19 U1 1 U2 25 PU UNIV ARIZONA DEPT GEOSCIENCES PI TUCSON PA RADIOCARBON 4717 E FORT LOWELL RD, TUCSON, AZ 85712 USA SN 0033-8222 J9 RADIOCARBON JI Radiocarbon PY 2008 VL 50 IS 1 BP 83 EP 97 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 287QJ UT WOS:000254931300007 ER PT J AU Poineau, F Du Mazaubrun, J Ford, D Fortner, J Kropf, J Silva, GWC Smith, N Long, K Jarvinen, G Czerwinski, K AF Poineau, F. Du Mazaubrun, J. Ford, D. Fortner, J. Kropf, J. Silva, G. W. C. Smith, N. Long, K. Jarvinen, G. Czerwinski, K. TI Uranium/technetium separation for the UREX process - synthesis and characterization of solid reprocessing forms SO RADIOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 11th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere CY AUG 26-31, 2007 CL Munich, GERMANY SP BMWi, Gesell Nuklear Serv, EnBW, DBE Technol, Natl Genossensch Lagerung Radioaktiver Abfalle, Forschungszentrum Karlsruhe DE Technetium; Uranium; Separation; UREX ID ABSORPTION FINE-STRUCTURE; X-RAY; THERMAL-DECOMPOSITION; AMMONIUM URANATE AB In the context of the demonstration of the UREX (uranium extraction) process, a separation of uranium and technetium using an anion exchange resin was performed on a simulant solution containing 98.95 g/L of (238)U and 130.2mg/L of (99)Tc. After sorption on the resin, TCO(4)(-) was eluted with NH(4)OH, the eluting stream was treated, and the technetium converted to Tc metal (yield = 52.5%). The purity of the compound was analyzed: it contains less than 23.8 mu g of 131 U per gram of (99)Tc. Tc metal was characterized by X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) spectroscopy; EXAFS analysis clearly confirms the hexagonal structure of the metal obtained after treatment. Uranium was converted to ammonium diuranate and to U(3)O(8) in a yield of 88.2%, analysis indicates that the compound contains less than 0.16 mu g of (99)Tc per gram of ammonium diuaranate. C1 [Poineau, F.; Du Mazaubrun, J.; Silva, G. W. C.; Czerwinski, K.] Univ Nevada, Harry Reid Ctr Environm Studies, Las Vegas, NV 89154 USA. [Ford, D.; Long, K.; Jarvinen, G.] Los Alamos Natl Lab, GT Seaborg Inst, Stockpile Mfg & Support Directorate, Los Alamos, NM 87545 USA. [Fortner, J.; Kropf, J.] Argonne Natl Lab, Div Chem Engn, Argonne, IL 60439 USA. RP Poineau, F (reprint author), Univ Nevada, Harry Reid Ctr Environm Studies, Las Vegas, NV 89154 USA. EM freder29@unlv.nevada.edu RI ID, MRCAT/G-7586-2011; Silva, Chinthaka/E-1416-2017 OI Silva, Chinthaka/0000-0003-4637-6030 NR 21 TC 16 Z9 16 U1 0 U2 19 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2008 VL 96 IS 9-11 BP 527 EP 533 DI 10.1524/ract.2008.1533 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 375EI UT WOS:000261096500004 ER PT J AU Zehnder, RA Batista, ER Scott, BL Peper, SM Goff, GS Runde, WH AF Zehnder, R. A. Batista, E. R. Scott, B. L. Peper, S. M. Goff, G. S. Runde, W. H. TI Synthesis, crystallographic characterization, and conformational prediction of a structurally unique molecular mixed-ligand U(VI) solid, Na(6)[UO(2)(O(2))(2)(OH)(2)](OH)(2)center dot 14H(2)O SO RADIOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 11th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere CY AUG 26-31, 2007 CL Munich, GERMANY SP BMWi, Gesell Nuklear Serv, EnBW, DBE Technol, Natl Genossensch Lagerung Radioaktiver Abfalle, Forschungszentrum Karlsruhe DE Uranium; Structure; Peroxide; Hydroxide ID URANYL TRIPEROXIDE; CRYSTAL-STRUCTURE; COMPLEXES; PEROXIDE; ION; PSEUDOPOTENTIALS; COORDINATION; CHEMISTRY; CARBONATE; EXCHANGE AB The first mononuclear molecular mixed-ligand U(VI) solid containing hydroxide and peroxide ligands,Na(6)[UO(2)(O(2))(2)(OH)(2)](OH)(2)center dot 14H(2)O (I), was synthesized and structurally characterized using single crystal X-ray diffraction. The crystal structure of I consisted of [UO(2)(O(2))(2)(OH)(2)](4-) molecular units, with a uranyl(VI) moiety perpendicular to 6 equatorial O atoms belonging to two side-on trans peroxo groups and two terminal trans hydroxo groups. Density functional theory (DFT) calculations determined that the trans-conformer of the [UO(2)(O(2))(2)(OH)(2)](4-) molecular unit found in I was 24kcal/mol lower in energy than the previously proposed cis-conformer. Crystal data: monoclinic, space group P2(1)/n with a = 13.357(4) angstrom, b 5.8521(15) angstrom, c = 15.948(6) angstrom, beta = 112.292(4)degrees, and Z = 2. C1 [Zehnder, R. A.; Scott, B. L.; Peper, S. M.; Goff, G. S.; Runde, W. H.] Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. [Batista, E. R.] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Runde, WH (reprint author), Los Alamos Natl Lab, Div Chem, POB 1663, Los Alamos, NM 87545 USA. EM runde@lanl.gov RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 25 TC 12 Z9 12 U1 1 U2 6 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2008 VL 96 IS 9-11 BP 575 EP 578 DI 10.1524/ract.2008.1539 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 375EI UT WOS:000261096500010 ER PT J AU Wang, Z Zachara, JM Liu, C Gassman, PL Felmy, AR Clark, SB AF Wang, Z. Zachara, J. M. Liu, C. Gassman, P. L. Felmy, A. R. Clark, S. B. TI A cryogenic fluorescence spectroscopic study of uranyl carbonate, phosphate and oxyhydroxide minerals SO RADIOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 11th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere CY AUG 26-31, 2007 CL Munich, GERMANY SP BMWi, Gesell Nuklear Serv, EnBW, DBE Technol, Natl Genossensch Lagerung Radioaktiver Abfalle, Forschungszentrum Karlsruhe DE Uranium; Fluorescence; Cryogenic temperature; Time-resolved; Carbonate; Phosphate ID LASER-INDUCED FLUORESCENCE; ELECTRONIC-STRUCTURE; ACTINYL IONS; URANIUM SPECIATION; LUMINESCENCE; COMPLEXES; CALCITE; WATERS; TRLFS; U(VI) AB In this work we applied time-resolved laser-induced fluorescence spectroscopy (TRLIF) at both room temperature (RT) and near liquid-helium temperature (6 K) to characterize a series of natural and synthetic minerals of uranium carbonate, phosphate and oxyhydroxides including rutherfordine, zellerite, liebigite, phosphuranylite, meta-autunite, meta-torbernite, uranyl phosphate, sodium-uranyl-phosphate, becquerelite, schoepite, meta-schoepite, dehydrated schoepite and compreignacite, and have compared the spectral characteristics among these minerals as well as our previously published data on uranyl silicates. For the carbonate minerals, the fluorescence spectra of rutherfordine showed significant difference from those of zellerite and liebigite. The fluorescence spectra of the phosphate minerals closely resemble each other despite the differences in their composition and structure. For all uranium oxyhydroxides, the fluorescence spectra are largely red-shifted as compared to those of the uranium carbonates and phosphates and their vibronic bands are broad and less resolved at RT. The enhanced spectra resolution at 6 K allows more accurate determination of the fluorescence band origin and offers a complemental method to measure the O=U=O symmetrical stretch frequency, v(1), from the spacings of the vibronic bands of the fluorescence spectra. The average v(1) values appear to be inversely correlated with the average pK(a) values of the anions. C1 [Wang, Z.; Zachara, J. M.; Liu, C.; Gassman, P. L.; Felmy, A. R.] Pacific NW Natl Lab, Richland, WA 99352 USA. [Clark, S. B.] Washington State Univ, Pullman, WA 99164 USA. RP Wang, Z (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM zheming.wang@pnl.gov RI Liu, Chongxuan/C-5580-2009; Wang, Zheming/E-8244-2010 OI Wang, Zheming/0000-0002-1986-4357 NR 42 TC 19 Z9 19 U1 3 U2 31 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2008 VL 96 IS 9-11 BP 591 EP 598 DI 10.1524/ract.2008.1541 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 375EI UT WOS:000261096500012 ER PT J AU Wang, Z Wagnon, KB Ainsworth, CC Liu, C Rosso, KM Fredrickson, JK AF Wang, Z. Wagnon, K. B. Ainsworth, C. C. Liu, C. Rosso, K. M. Fredrickson, J. K. TI A spectroscopic study of the effect of ligand complexation on the reduction of uranium(VI) by anthraquinone-2,6-disulfonate (AH(2)DS) SO RADIOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 11th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere CY AUG 26-31, 2007 CL Munich, GERMANY SP BMWi, Gesell Nuklear Serv, EnBW, DBE Technol, Natl Genossensch Lagerung Radioaktiver Abfalle, Forschungszentrum Karlsruhe DE Kinetics; Stopped-flow; Uranium; Uranyl complex; Electron transferr; Anthraquinone-2,6-disulfonate ID ELECTRON-TRANSFER KINETICS; ANTHRAQUINONE SULFONATES; MICROBIAL REDUCTION; U(VI); SPECIATION; HEMATITE; IRON; SUSPENSIONS; CHEMISTRY; ACTINIDES AB In this paper, the reduction rate of uranyl complexes with hydroxide, carbonate, EDTA, and desferriferrioxamine B (DFB) by anthraquinone-2,6-disulfonate (AH(2)DS) is studied by stopped-flow kinetic technique under anoxic atmosphere. The apparent reaction rates varied with ligand type, solution pH, and U(VI) concentration. For each ligand, a single largest pseudo-1(st) order reaction rate constant, k(obs), within the studied pH range was observed, suggesting the influence of pH-dependent speciation on the U(VI) reduction rate. The maximum reaction rate found in each case followed the order of OH(-) > CO(3)(2-) > EDTA > DFB, in reverse order of the trend of the thermodynamic stability of the uranyl complexes and ionic sizes of the ligands. The pH-dependent rates were modeled using a second-order rate expression that was assumed to be dependent on a single U(VI) complex and an AH(2)DS species. By quantitatively comparing the calculated and measured apparent rate constants as a function of pH, species AHDS(3-) was suggested as the primary reductant in all cases examined. Species UO(2)CO(3)(aq), UO(2)HEDTA(-), and (UO(2))(2)(OH)(2)(2+) were suggested as the principal electron acceptors among the U(VI) species mixture in each of the carbonate, EDTA, and hydroxyl systems, respectively. C1 [Wang, Z.; Wagnon, K. B.; Ainsworth, C. C.; Liu, C.; Rosso, K. M.; Fredrickson, J. K.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wang, Z (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM Zheming.wang@pln.gov RI Liu, Chongxuan/C-5580-2009; Wang, Zheming/E-8244-2010 OI Wang, Zheming/0000-0002-1986-4357 NR 35 TC 2 Z9 2 U1 0 U2 10 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2008 VL 96 IS 9-11 BP 599 EP 605 DI 10.1524/ract.2008.1542 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 375EI UT WOS:000261096500013 ER PT J AU Hennig, C Ikeda, A Schmeide, K Brendler, V Moll, H Tsushima, S Scheinost, AC Skanthakumar, S Wilson, R Soderholm, L Servaes, K Gorrler-Walrand, C Van Deun, R AF Hennig, C. Ikeda, A. Schmeide, K. Brendler, V. Moll, H. Tsushima, S. Scheinost, A. C. Skanthakumar, S. Wilson, R. Soderholm, L. Servaes, K. Gorrler-Walrand, C. Van Deun, R. TI The relationship of monodentate and bidentate coordinated uranium(VI) sulfate in aqueous solution SO RADIOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 11th International Conference on Chemistry and Migration Behaviour of Actinides and Fission Products in the Geosphere CY AUG 26-31, 2007 CL Munich, GERMANY SP BMWi, Gesell Nuklear Serv, EnBW, DBE Technol, Natl Genossensch Lagerung Radioaktiver Abfalle, Forschungszentrum Karlsruhe DE EXAFS; HEXS; UV-vis; Uranyl sulfate; Aqueous solution ID COMPLEXES; SPECTROSCOPY; SPECIATION; U(VI); ION AB The coordination of U(VI) sulfate complexes has been investigated by uranium L(III)-edge EXAFS and HEXS measurements with the aim to distinguish monodentate and bidentate coordinated sulfate in aqueous solution. UV-vis absorption spectroscopy has been used to differentiate the species and to determine the species distribution as a function of the [SO(4)(2-)]/[UO(2)(2+)] ratio. A monodentate coordination prevails in solutions with [SO(4)(2-)]/[UO(2)(2+)] ratio of 1, where UO(2)SO(4) is the dominant species. Besides the dominating monodentate sulfate a small amount of bidentate sulfate could be observed, indicating that two isomers may exist for UO(2)SO(4). With increasing [SO(4)(2-)]/[UO(2)(2+)] ratio the UP(2)(SO(4))(2)(2-) species becomes the main species. The uranium atom of this species is coordinated by two bidentate Sulfate groups. C1 [Hennig, C.; Ikeda, A.; Schmeide, K.; Brendler, V.; Moll, H.; Tsushima, S.; Scheinost, A. C.] Forschungszentrum Dresden Rossendorf, Inst Radiochem, D-01314 Dresden, Germany. [Skanthakumar, S.; Wilson, R.; Soderholm, L.] Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. [Servaes, K.; Gorrler-Walrand, C.; Van Deun, R.] Katholieke Univ Leuven, Dept Chem, B-3001 Heverlee, Belgium. RP Hennig, C (reprint author), Forschungszentrum Dresden Rossendorf, Inst Radiochem, D-01314 Dresden, Germany. EM hennig@esrf.fr RI Tsushima, Satoru/B-4103-2008; The Rossendorf Beamline at ESRF, ROBL/A-2586-2011; Wilson, Richard/H-1763-2011; Scheinost, Andreas/D-2275-2010; Van Deun, Rik/I-1632-2014 OI Tsushima, Satoru/0000-0002-4520-6147; Wilson, Richard/0000-0001-8618-5680; Van Deun, Rik/0000-0001-7091-6864 NR 17 TC 20 Z9 20 U1 9 U2 29 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2008 VL 96 IS 9-11 BP 607 EP 611 DI 10.1524/ract.2008.1543 PG 5 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 375EI UT WOS:000261096500014 ER PT J AU Levitskaia, TG Sinkov, SI Lumetta, GJ AF Levitskaia, T. G. Sinkov, S. I. Lumetta, G. J. TI Actinide binding by Klaui ligands: REDOX speciation and sorption on an extraction chromatography resin SO RADIOCHIMICA ACTA LA English DT Article DE Klaui ligand; Actinide complexes; Sorption; Separation; UV-vis spectral characterization ID RAY CRYSTAL-STRUCTURE; PENTAVALENT NEPTUNIUM; SANDWICH COMPOUNDS; NITRATE COMPLEXES; NITRIC ACID; ABSORPTION; NMR; REACTIVITY; SPECTRA AB The sorption of Eu(III) and actinide ions in various oxidation states from nitric acid Solutions by an extraction chromatography resin containing 1 wt. % of the Klaui ligand Cp*Co[*P(O)(OR)(2)](3)(-) [Cp* = pentamethylcyclopentadienyl, R = -CH(2)CH(2)CH(3)] oil Amberlite (R) XAD-7HP was examined. At 0.3 M HNO(3) and a metal-to-ligand ratio of 0.07, the relative affinity of the resin for the ions investigated followed the order: tetravalent >> hexavalent > trivalent > pentavalent; however, the relative affinity for the trivalent and hexavalent ions can be reversed, depending on the extent of ligand loading and the nitric acid concentration. The sorption of the tetravalent ions was exceptionally strong in the entire range of nitric acid concentration examined (0.2 to 8 M HNO(3))The large difference in the affinity of the resin with the Klaui ligand for tetravalent actinides compared to hexavalent actinides is unusual for ligands with the P=O donor moiety. Resin samples loaded with various actinide ions were examined spectrophotometrically. No Np(V) and Pu(III) Species were identified Onl the resin; rather, reduction-oxidation (REDOX) reactions occurred during equilibration, resulting in their complete conversion to M(IV) species bound by the Klaui ligand. Similarly, the sorption behavior of Pu(VI) and Np(VI) was complicated by their reduction to M(IV) upon sorption. The observed REDOX processes were apparently driven by the extremely high affinity of the Klaui ligand for the tetravalent ions. The acid-base properties of the methyl derivative of the Klaui ligand were investigated in aqueous solution, and its pK(a) was found to be highly dependent upon the solution ionic strength. The binding constants of this ligand with various actinide ions measured in a mixed methanol/carbon tetrachloride solvent exhibited qualitative agreement with the sorption selectivity trends. C1 [Levitskaia, T. G.; Sinkov, S. I.; Lumetta, G. J.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Lumetta, GJ (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM gregg.lumetta@pnl.gov FU National Nuclear Security Agency [NA-22]; Battelle for the U.S. Department of Energy [DE-AC05-76RL01830] FX This work was funded by the National Nuclear Security Agency (NA-22). Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy under Contract DE-AC05-76RL01830. NR 42 TC 2 Z9 2 U1 1 U2 2 PU OLDENBOURG VERLAG PI MUNICH PA LEKTORAT MINT, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0033-8230 J9 RADIOCHIM ACTA JI Radiochim. Acta PY 2008 VL 96 IS 12 BP 805 EP 815 DI 10.1524/ract.2008.1524 PG 11 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 387IN UT WOS:000261945100006 ER PT J AU Larson, TE Heikoop, JM Perkins, G Chipera, SJ Hess, MA AF Larson, Toti E. Heikoop, Jeffrey M. Perkins, George Chipera, Steve J. Hess, Marcey A. TI Pretreatment technique for siderite removal for organic carbon isotope and C : N ratio analysis in geological samples SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID MARINE-SEDIMENTS; NITROGEN; ANALYZER; ACID AB A method for the removal of siderite from geological samples to determine organic carbon isotope compositions using elemental analysis isotope ratio mass spectrometry is presented which includes calculations for % organic carbon in samples that contain diagenetic carbonate. The proposed method employs in situ acidification of geological samples with 6 N HCl and silver capsule sample holders and was tested on modem peach leaf samples (NIST 1547) and ancient lacustrine samples from Valles Caldera, New Mexico. The in situ acidification technique eliminates potential errors associated with the removal of soluble organic material using standard acid decanting techniques and allows for removal of the less soluble siderite, which is not efficiently removed using vapor acidification techniques. Copyright (C) 2008 John Wiley & Sons, Ltd. C1 [Larson, Toti E.; Heikoop, Jeffrey M.; Perkins, George; Hess, Marcey A.] Los Alamos Natl Lab, Earth & Environm Sci Div, Hydrol Geochem & Geol Grp, Los Alamos, NM 87545 USA. [Chipera, Steve J.] Chesapeake Energy Corp, Oklahoma City, OK 73118 USA. RP Larson, TE (reprint author), Los Alamos Natl Lab, Earth & Environm Sci Div, Hydrol Geochem & Geol Grp, MS D469, Los Alamos, NM 87545 USA. EM tlarson@lanl.gov RI Heikoop, Jeffrey/C-1163-2011; OI Larson, Toti/0000-0002-2291-5979; Heikoop, Jeffrey/0000-0001-7648-3385 NR 10 TC 12 Z9 12 U1 2 U2 13 PU JOHN WILEY & SONS LTD PI CHICHESTER PA THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PY 2008 VL 22 IS 6 BP 865 EP 872 DI 10.1002/rcm.3432 PG 8 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA 282UW UT WOS:000254593700014 PM 18293285 ER PT S AU Wadley, H Zhou, X Butler, WH AF Wadley, H. Zhou, X. Butler, W. H. BE Depla, D Manhieu, S TI Atomic Assembly of Magnetoresistive Multilayers SO REACTIVE SPUTTER DEPOSITION SE Springer Series in Materials Science LA English DT Article; Book Chapter ID MOLECULAR-DYNAMICS SIMULATIONS; ION-ASSISTED CONTROL; MAGNETIC TUNNELING JUNCTIONS; FIELD GIANT MAGNETORESISTANCE; HYPERTHERMAL VAPOR-DEPOSITION; SPUTTERED CO/CU MULTILAYERS; ELECTRICAL SPIN INJECTION; INTERFACIAL STRUCTURE; SURFACE SEGREGATION; ENHANCED MAGNETORESISTANCE C1 [Wadley, H.] Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. [Zhou, X.] Sandia Natl Labs, Dept Mech Mat, Livermore, CA USA. [Butler, W. H.] Univ Alabama, Dept Phys & Astron, Tuscaloosa, AL 35487 USA. RP Wadley, H (reprint author), Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. EM hnw4z@virginia.edu; xzhou@sandia.gov; wbutler@mint.ua.edu NR 127 TC 2 Z9 2 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0933-033X BN 978-3-540-76662-9 J9 SPRINGER SER MATER S PY 2008 VL 109 BP 497 EP 559 D2 10.1007/978-3-540-76664-3 PG 63 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BJM24 UT WOS:000266793800014 ER PT S AU Holden, NE Reciniello, RN Hu, JP Leith, J Tehan, TN AF Holden, N. E. Reciniello, R. N. Hu, J. -P Leith, J. Tehan, T. N. BE Vehar, DW Gilliam, DM Adams, JM TI Reactor dosimetry study of the Rhode Island Nuclear Science Center SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE American Society for Testing and Materials Special Technical Publications LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE RINSC; neutron dose; gamma dose; MCNP; neutron flux; photon flux; TLD AB The RINSC is a 2 MW light water reactor that has a graphite thermal column, that is used for educational and industrial applications as well as for biological research. A series of measurements and calculations have been performed in this thermal column. Thermoluminescent dosimeter measurements of the neutron dose rate and the gamma-ray dose rate, as well as bare gold foil and cadmium covered gold foil measurements of the thermal and epithermal neutron flux densities are graphically compared to MCNP Monte Carlo calculations. C1 [Holden, N. E.; Reciniello, R. N.; Hu, J. -P] Brookhaven Natl Lab, Natl Nucl Data Center, Upton, NY 11973 USA. RP Holden, NE (reprint author), Brookhaven Natl Lab, Natl Nucl Data Center, Upton, NY 11973 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 26 EP 33 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800004 ER PT S AU Griffin, PJ Luker, SM King, DB DePriest, KR Cooper, PJ AF Griffin, Patrick J. Luker, S. Michael King, Donald B. DePriest, K. Russell Cooper, Philip J. BE Vehar, DW Gilliam, DM Adams, JM TI Characterizing the time- and energy-dependent reactor n/gamma environment SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE American Society for Testing and Materials Special Technical Publications LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE dosimeter; delayed gamma; PCD; active dosimetry; PIN; calorimeter; radiation rate; flux; activation; fluence rate; fission chamber; ionization chamber; SPND AB In a reactor pulse, the early radiation has a neutron/gamma component resulting from the prompt fission neutron and gamma radiation and from the neutron-induced secondary gammas. However, after the primary reactor pulse, the radiation environment also includes a time-dependent delayed neutron and gamma component. At even later times, the material activation dominates the source term. When active tests are conducted in the reactor, the radiation environment at a particular time may not be well characterized by the time-integrated spectrum provided by the typical radiation transport calculations. This paper defines the steps that are required to adequately model the time- and energy-dependent radiation environment in the reactor environment. This paper also compares the time-dependent response from a range of active dosimeters in a reactor pulsed environment and shows how the n/gamma mixed-field response for the dosimeters and the changing radiation field can influence the interpretation of the dosimetry. C1 [Griffin, Patrick J.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Griffin, PJ (reprint author), Sandia Natl Labs, POB 5800,MS1146, Albuquerque, NM 87185 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 43 EP 54 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800006 ER PT S AU Remec, I Rosseel, TM Blakeman, ED Baldwin, CA Heatherly, DW Thoms, KR AF Remec, Igor Rosseel, Thomas M. Blakeman, Edward D. Baldwin, Charles A. Heatherly, Dennis W. Thoms, Kenneth R. BE Vehar, DW Gilliam, DM Adams, JM TI Characterization of the neutron field in the HSSI reusable irradiation facility at the Ford Nuclear Reactor SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE American Society for Testing and Materials Special Technical Publications LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE neutron irradiation; embrittlement; TORT; dosimetry AB The characterization of the neutron environment in a reusable facility for irradiation of metallurgical specimens, located at the Ford Nuclear reactor in Michigan, was performed with a combination of transport calculations, extensive dosimeter measurements, and neutron spectrum adjustment. The average difference between the calculated and "measured" reaction rates was similar to 7 % (the calculations underpredicted the measurements), and the average absolute difference was similar to 10 %. Therefore, the calculations and measurements agreed very well. The flexible facility performed excellently during several years of operation but was discontinued when the Ford reactor ceased operation. The heavy-section steel irradiation (HSSI) program is taking the initial steps toward selecting a site for a new irradiation facility, similar to the one described here. C1 [Rosseel, Thomas M.] Oak Ridge Natl Lab, HSSI, Oak Ridge, TN 37831 USA. RP Remec, I (reprint author), Oak Ridge Natl Lab, HSSI, POB 2008, Oak Ridge, TN 37831 USA. RI Rosseel, Thomas/J-4086-2016 OI Rosseel, Thomas/0000-0001-9917-7073 NR 6 TC 0 Z9 0 U1 0 U2 3 PU AMER SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 90 EP 97 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800011 ER PT S AU DePriest, KR AF DePriest, K. Russell BE Vehar, DW Gilliam, DM Adams, JM TI Benchmark experiments/calculations of neutron environments in the annular core research reactor SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE ACRR; MCNPX; reactor benchmarks; neutron environments; reactor test facilities AB Benchmark experiments using spherical test objects were performed in the central cavity of Sandia National Laboratories' Annular Core Research Reactor. The experiments were performed with 10.16 cm and 17.78 cm diameter aluminum (Al6061) and high-density polyethylene spheres that were essentially solid with cavities scrolled out along the equator to allow the insertion of activation foils and/or sulfur pellets. The neutron monitor foils were selected to cover a wide range of reaction energies. The reactor environments were modeled in detail using Monte Carlo N-Particle eXtended (MCNPX). The experimental results were compared to the Monte Carlo calculations of the reaction rates of each of the foils at various depths in the spheres produced by MCNPX. The comparison includes a complete treatment of the uncertainties. C1 Sandia Natl Labs, Appl Nucl Technol Dept, Albuquerque, NM 87185 USA. RP DePriest, KR (reprint author), Sandia Natl Labs, Appl Nucl Technol Dept, POB 5800,MS 1146, Albuquerque, NM 87185 USA. NR 8 TC 0 Z9 0 U1 1 U2 1 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 98 EP 108 PG 11 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800012 ER PT S AU Holden, NE Reciniello, RN Hu, JP AF Holden, N. E. Reciniello, R. N. Hu, J. -P. BE Vehar, DW Gilliam, DM Adams, JM TI Radiation dosimetry in the BNCT patient treatment room at the Brookhaven Medical Research Reactor SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE American Society for Testing and Materials Special Technical Publications LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE BNCT; BMRR; neutron dose; gamma dose; epithermal neutrons ID NEUTRON-CAPTURE THERAPY; GLIOBLASTOMA-MULTIFORME AB The BMRR was a 3 MW light water reactor that had an epithermal neutron beam that was used to perform clinical trials on patients with malignant brain tumors. A series of measurements and calculations had been performed in the treatment room both prior to the trials and during the trials. The details of the measurements and the Monte Carlo calculations are presented and compared. C1 [Holden, N. E.] Brookhaven Natl Lab, Natl Nucl Data Ctr, Upton, NY 11973 USA. RP Holden, NE (reprint author), Brookhaven Natl Lab, Natl Nucl Data Ctr, Upton, NY 11973 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 130 EP 136 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800016 ER PT S AU Holden, NE AF Holden, N. E. BE Vehar, DW Gilliam, DM Adams, JM TI Survey of the latest evaluated nuclear data SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE half lives; new chemical elements; superheavy elements; errors ID BETA-DECAY; HALF-LIFE AB The results of a review and evaluation of nuclear data published in the scientific literature are presented. The status of new chemical elements that have been discovered and officially named and the latest data for new elements that have been claimed are examined. Half lives of very long-lived nuclides are presented. Data on the very heavy elements are tabulated. The problems presented by the attempt to estimate errors for the various nuclear data are considered as well as the psychological aspect of error estimation are also discussed. C1 Brookhaven Natl Lab, Natl Nucl Data Ctr, Upton, NY 11973 USA. RP Holden, NE (reprint author), Brookhaven Natl Lab, Natl Nucl Data Ctr, Upton, NY 11973 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 163 EP 168 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800020 ER PT S AU Ferguson, PD Gallmeier, FX Mansur, LK Wechsler, AS AF Ferguson, P. D. Gallmeier, F. X. Mansur, L. K. Wechsler, A. S. BE Vehar, DW Gilliam, DM Adams, JM TI Mesh tally radiation damage calculations and application to the SNS target system SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE displacements; helium production; MCNPX; mesh tally method; neutron irradiation; proton irradiation; radiation damage; silicon production; SNS AB A new method for the calculation of radiation damage parameters in large geometries encompassing multiple materials using the MCNPX mesh tally has been developed. The method has been tested against previously published calculations of the displacement rate for protons and neutrons at the center of the SNS 316LN stainless steel target vessel nose. Displacement rates for neutrons, protons, and the total using the mesh tally method are shown to agree with previous work. The mesh tally method is also applied to the SNS aluminum moderator vessels and to the SNS inner reflector plug composed of aluminum, beryllium, and stainless steel. Results are given for displacement, helium, and silicon production rates. C1 [Ferguson, P. D.; Gallmeier, F. X.; Mansur, L. K.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ferguson, PD (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 9 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 184 EP 189 PG 6 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800023 ER PT S AU Remec, I Glasgow, DC Haines, JR Johnson, JO AF Remec, Igor Glasgow, David C. Haines, John R. Johnson, Jeffrey O. BE Vehar, DW Gilliam, DM Adams, JM TI Proton induced activation in mercury: Comparison of measurements and calculations SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE proton beam; mercury; activation; MCNPX; gamma rays; dose rate AB Measurements and simulations of the proton beam interaction with the mercury target were performed to support Spallation Neutron Source design. Due to the abundance of isotopes produced in mercury, the long delay between the irradiation and the measurements, and the self-shielding of the mercury sample, the measurements were difficult to perform and the activities of several isotopes have large uncertainties. Calculations predicted the activities of the most reliably measured isotopes within 20%/40%; however, some large discrepancies were observed for some isotopes for which the measurements were considered less reliable. Predicted dose rates were in very good agreement with the measurements. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Remec, I (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 6 TC 0 Z9 0 U1 2 U2 4 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 220 EP 227 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800028 ER PT S AU Alpan, FA Haghighat, A AF Alpan, F. Arzu Haghighat, Alireza BE Vehar, DW Gilliam, DM Adams, JM TI Use of CPXSD for generation of effective fast multigroup libraries for pressure vessel fluence calculations SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE American Society for Testing and Materials Special Technical Publications LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE multigroup library; pressure vessel fluence; contributon; adjoint; cross section AB Multigroup (i.e., broad-group) libraries play a significant role in the accuracy of transport calculations. There are several broad-group libraries available for particular applications. For example the 47-neutron (26 fast groups), 20-gamma-group BUGLE libraries are commonly used for light water reactor shielding and pressure vessel dosimetry problems. However, there is no publicly available methodology to construct group structures for a problem and objective of interest. Therefore, we have developed the Contributon and Point-wise Cross-Section Driven (CPXSD) methodology, which constructs effective fine-and broad-group structures. In this paper, we use the CPXSD methodology to construct broad-group structures for fast neutron dosimetry problems. It is demonstrated that the broad-group libraries generated from CPXSD constructed group structures, while only 14 groups (rather than 26 groups) in the fast energy range are in good agreement (similar to 1 %-2 %) with the fine-group library from which they were derived, in reaction rate calculations. C1 [Alpan, F. Arzu] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Alpan, FA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 11 TC 0 Z9 0 U1 0 U2 1 PU AMER SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 313 EP 320 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800040 ER PT S AU Broadhead, BL Williams, ML Wagschal, JJ AF Broadhead, B. L. Williams, M. L. Wagschal, J. J. BE Vehar, DW Gilliam, DM Adams, JM TI Generalized linear least-squares adjustment, revisited SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE TSURFER; SCALE; GLLS; adjustment; uncertainties; LEPRICON; inconsistency; rejection; ENDF/B; ICSBEP ID UNFOLDING PROCEDURE; DOSIMETRY; REACTOR AB TSURFER, a generalized linear least-squares (GLLS) code, is a new module of the SCALE system. After a short introduction outlining the history and applications of the GLLS methodology in reactor physics, a new application of the GLLS methodology in criticality safety is discussed. Some characteristic TSURFER input data are discussed in detail. C1 [Broadhead, B. L.; Williams, M. L.] Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Broadhead, BL (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37830 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 340 EP 347 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800043 ER PT S AU Greenwood, LR Oliver, BM AF Greenwood, Lawrence R. Oliver, Brian M. BE Vehar, DW Gilliam, DM Adams, JM TI Comparison of predicted and measured helium production in USBWR reactors SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE helium; BWR AB Helium production in reactor steel is calculated as the summation of all neutron reactions that produce helium either with thermal or fast neutrons. Thermal helium production is due to elements or impurities that are known to have a thermal neutron cross section for helium production, including B-10 and Ni-59. Fast neutrons produce helium in all materials due to the threshold (n,alpha) reactions as well as other reactions that include helium as one of the reaction products. A generalized equation is given for helium production in all reactor materials and comparisons are given for helium measurements in steel and inconel samples. The helium production calculated using the generalized equation is in good agreement with helium measurements in samples from BWR reactors. Simplified equations are given with numerical values and generic parameters to facilitate calculations. However, it is important to use the actual boron content when known to obtain reliable estimates of the helium production. C1 [Greenwood, Lawrence R.; Oliver, Brian M.] Pacific NW Natl Lab, Richland, WA 99354 USA. RP Greenwood, LR (reprint author), Pacific NW Natl Lab, Richland, WA 99354 USA. RI Greenwood, Lawrence/H-9539-2016 OI Greenwood, Lawrence/0000-0001-6563-0650 NR 8 TC 0 Z9 0 U1 0 U2 2 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 356 EP 364 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800045 ER PT S AU Slater, CO Selby, DL Bucholz, JA Robertson, JL Crow, ML AF Slater, C. O. Selby, D. L. Bucholz, J. A. Robertson, J. L. Crow, M. L. BE Vehar, DW Gilliam, DM Adams, JM TI Shielding calculations for the upgrade of the HFIR HB 2 beam line SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE shielding calculations; HFIR; dose rates; dose measurements; beam line; discrete ordinates; Monte Carlo AB Experimental facilities at the Oak Ridge National Laboratory's High Flux Isotope Reactor are being upgraded through the redesign of beam tubes supplying neutrons to those facilities. In support of the shield design for one of the beam lines HB-2, calculations were performed to determine dose rates outside the shielding as well as background radiation levels at various locations around the instrumentation. Low-power (10 % power) as well as full-power measurements were made at key locations, and calculated results were compared with corresponding measured results. This paper describes the calculations and compares the measured and calculated results. Most of the measured results, when normalized to the full-operating-power level, compared favorably with the calculated results. One differed by a factor of 2.5, and another differed by a factor of 6. Based on this agreement, one can infer that reasonable calculations for some three-dimensional shield designs can be performed using two-dimensional methods and two-dimensional approximations to the three-dimensional geometry. The results confirmed the adequacy of the design. C1 [Slater, C. O.; Selby, D. L.; Bucholz, J. A.; Robertson, J. L.; Crow, M. L.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Slater, CO (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 365 EP 372 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800046 ER PT S AU Luker, SM Griffin, PJ DePriest, KR King, DB Naranjo, GE Suo-Anttila, AJ Keltner, N AF Luker, S. Michael Griffin, Patrick J. DePriest, K. Russell King, Donald B. Naranjo, Gerald E. Suo-Anttila, Ahti J. Keltner, Ned BE Vehar, DW Gilliam, DM Adams, JM TI Development of a silicon calorimeter for dosimetry applications in a water-moderated reactor SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE thermal neutron; silicon calorimeter; PCD AB High fidelity active dosimetry in the mixed neutron/gamma field of a research reactor is a very complex issue. For passive dosimetry applications, the use of activation foils addresses the neutron environment while the use of low neutron response CaF2:Mn thermoluminescent dosimeters (TLDs) addresses the gamma environment. While radiation-hardened diamond pholoconducting detectors (PCD) have been developed that provide a very precise fast response (picosecond) dosimeter and can provide a time-dependent profile for the radiation environment, the mixed field response of the PCD is still uncertain and this interferes with the calibration of the PCD response. In order to address the research reactor experimenter's need for a dosimeter that reports silicon dose and dose rate at a test location during a pulsed reactor operation, a silicon calorimeter has been developed. This dosimeter can be used by itself to provide a dose in rad(Si) up to a point in a reactor pulsed operation, or, in conjunction with the diamond PCD, to provide a dose rate. This paper reports on the development, testing, and validation of this silicon calorimeter for applications in water-moderated research reactors. C1 [Luker, S. Michael; Griffin, Patrick J.; DePriest, K. Russell; King, Donald B.; Naranjo, Gerald E.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Luker, SM (reprint author), Sandia Natl Labs, POB 5800,MS1146, Albuquerque, NM 87185 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 389 EP 397 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800048 ER PT S AU Luker, SM Griffin, PJ DePriest, KR King, DB Naranjo, GE Suo-Anttila, AJ AF Luker, S. Michael Griffin, Patrick J. DePriest, K. Russell King, Donald B. Naranjo, Gerald E. Suo-Anttila, Ahti J. BE Vehar, DW Gilliam, DM Adams, JM TI Application of a silicon calorimeter in fast burst reactor environments SO REACTOR DOSIMETRY: 12TH INTERNATIONAL SYMPOSIUM SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 12th International Symposium on Reactor Dosimetry CY MAY 08-13, 2005 CL Gatlinburg, TN SP ASTM Int, European Working Grp Reactor Dosimetry, Atom Energy & Applicat, EWGRD DE calorimeter; silicon; fast burst reactor; PCD; dose; FBR; active dosimeter AB Frequently in experiments at fast burst reactors (FBRs), it is necessary to know the dose and peak dose rate absorbed by a material in terms of dose to silicon. The dose to silicon at a given point in an irradiation cannot be reliably measured by a passive dosimeter retrieved at late times from a mixed field environment, so we rely on the silicon calorimeter as the true standard. A silicon calorimeter has been developed for applications in a water-moderated pulsed reactor. In this paper, the authors investigate the application of this silicon calorimeter in an FBR environment. Tests have been conducted at the White Sands Missile Range (WSMR) FBR, also known as MoLLY-G, to develop techniques to use this silicon calorimeter for a measure of rad(Si) during and soon after a pulsed operation. This calorimeter can be coupled with the response of a diamond photoconductive detector (PCD) in order to derive a dose rate monitor suitable for application during an FBR operation [1]. C1 [Luker, S. Michael; Griffin, Patrick J.; DePriest, K. Russell; King, Donald B.; Naranjo, Gerald E.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Luker, SM (reprint author), Sandia Natl Labs, MS 1146, Albuquerque, NM 87185 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 978-0-8031-3412-6 J9 AM SOC TEST MATER PY 2008 VL 1490 BP 442 EP 449 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA BHY10 UT WOS:000257379800055 ER PT S AU Plum, MM AF Plum, M. M. BE Linkov, I Ferguson, E Magar, VS TI RATIONALE AND DEVELOPMENT OF A SCALE TO COMMUNICATE ENVIRONMENTAL AND OTHER COMMUNITY RISKS SO REAL-TIME AND DELIBERATIVE DECISION MAKING: APPLICATION TO EMERGING STRESSORS SE Nato Science for Peace and Security Series C - Environmental Security LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Risk, Uncertainly and Decision Analysis for Environmental Security and Non-Chemical Stressors CY APR, 2007 CL Estoril, PORTUGAL SP NATO AB Efforts to secure any community from environmental and other community risks must be able to convincingly argue that: 1. The stressors impact the community's well being. 2. The community is ultimately responsible in the mitigation of these stressors. 3. Limited resources must be committed to manage this risk to an acceptable level. Assuming any community has a fixed quantity of risk management funding, environmental security must compete for resources traditionally allocated to other well-recognized risks of war, terrorism, and natural disasters. Even if the quantity of funding is flexible, it must convincingly argue for the reallocation of scarce resources from the activities of consumption to investment. Economists refer to this discussion as "Guns or Butter." Similarly, the Department of Homeland Security must allocate resources to many risks. Calculated from probable events, probable outcomes, and probable life and economic losses, a risk scale developed within one DHS-funded program uses the rationale of many successful threat and risk scales. It was suggested that this scale could be used to measure and rank the risk of all international events of terror, disaster, and calamity for the allocation of risk management efforts. This paper examines a few notable and successful scales of risk, the rationale for these and the development of the Security Assurance Index, and the recently proposed Global Risk Index and its application to environmental security. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Plum, MM (reprint author), Idaho Natl Lab, Idaho Falls, ID 83415 USA. EM plummm@inel.gov NR 0 TC 0 Z9 0 U1 1 U2 1 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1871-4668 BN 978-1-4020-9024-0 J9 NATO SCI PEACE SECUR PY 2008 BP 103 EP 126 PG 24 WC Environmental Sciences; Operations Research & Management Science SC Environmental Sciences & Ecology; Operations Research & Management Science GA BIP16 UT WOS:000261511600007 ER PT S AU Grebenkov, A Yakushau, A Lukashevich, A Sullivan, T Linkov, I AF Grebenkov, A. Yakushau, A. Lukashevich, A. Sullivan, T. Linkov, I. BE Linkov, I Ferguson, E Magar, VS TI DECISION EVALUATION FOR COMPLEX ENVIRONMENTAL RISK NETWORKED SYSTEMS (DECERNS) Cost/Benefit Module and Application to Wildlife Reserve Management SO REAL-TIME AND DELIBERATIVE DECISION MAKING: APPLICATION TO EMERGING STRESSORS SE NATO Science for Peace and Security Series C-Environmental Security LA English DT Proceedings Paper CT NATO Advanced Research Workshop on Risk, Uncertainly and Decision Analysis for Environmental Security and Non-Chemical Stressors CY APR, 2007 CL Estoril, PORTUGAL SP NATO AB Decision Evaluation in Complex Risk Network Systems (DECERNS) is a computerized decision support system with the objective of providing a methodology, computer models and software tools that facilitate decision-making for sustainable land use planning, sediment management, and related issues. Cost-benefit analysis (CBA) is an essential component of environmental assessments. This approach introduces costs (i.e., monetary equivalents) of ecosystem services, but management decisions often require decision makers to integrate heterogeneous technical information with values and judgments. This paper introduces a CBA module developed as part of DECERNS and describes its linkages with a multicriteria decision analysis (MCDA) module that allows integration of monetized parameters with expert-driven estimates and ecological values of stakeholders that may be difficult to monetize. We describe the model's application to selection of land use alternatives for the Dikoye and Zvanets wildlife sanctuaries in Belarus. C1 [Grebenkov, A.; Yakushau, A.; Lukashevich, A.] Joint Inst Power & Nucl Res Sosny, Minsk, Byelarus. [Sullivan, T.] Brookhaven Natl Lab, Upton, NY 11973 USA. [Linkov, I.] US Army Engineer Res & Dev Ctr, Concord, MA USA. RP Grebenkov, A (reprint author), Joint Inst Power & Nucl Res Sosny, Minsk, Byelarus. EM tsullivan@bnl.gov; ilinkov@yahoo.com NR 6 TC 1 Z9 1 U1 1 U2 2 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1871-4668 BN 978-1-4020-9024-0 J9 NATO SCI PEACE SECUR JI NATO Sci. Peace Secur. Ser. C- Environ. Secur. PY 2008 BP 315 EP + PG 3 WC Environmental Sciences; Operations Research & Management Science SC Environmental Sciences & Ecology; Operations Research & Management Science GA BIP16 UT WOS:000261511600020 ER PT S AU Dreger, H Feldmann, A Paxson, V Sornmer, R AF Dreger, Holger Feldmann, Anja Paxson, Vern Sornmer, Robin BE Lippmann, R Kirda, E Trachtenberg, A TI Predicting the Resource Consumption of Network Intrusion Detection Systems SO RECENT ADVANCES IN INTRUSION DETECTION, RAID 2008 SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 11th International Symposium on Recent Advances in Intrusion Detection CY SEP 15-17, 2008 CL MIT Lincoln Lab, Cambridge, MA SP Inst Informat Infrastructure Protect, Symantec Corp, IBM HO MIT Lincoln Lab AB When installing network intrusion detection systems (NIDSs), operators are faced with a large number of parameters and analysis options for tuning trade-offs between detection accuracy versus resource requirements. In this work we set out to assist this process by understanding and predicting the CPU and memory consumption of such systems. We begin towards this goal by devising general NIDS resource model to capture the ways in which CPU and memory usage scale with changes in network traffic. We then use this model to predict the resource demands of different configurations in specific environments. Finally, we present an approach to derive site-specific NIDS configurations that maximize the depth of analysis given predefined resource constraints. We validate our approach by applying it to the open-source Bro NIDS, testing the methodology using real network data, and developing a corresponding tool, nidsconf, that automatically derives a set of configurations suitable for a given environment based on a sample of the site's traffic. While no automatically generated configuration can ever be optimal, these configurations provide sound starting points, with promise to significantly reduce the traditional trial-and-error NIDS installation cycle. C1 [Dreger, Holger] Siemens AG, Corp Technol, Earlangen, Germany. [Feldmann, Anja] Tech Univ Berlin, Deutsch Telekom Lab, Berlin, Germany. [Paxson, Vern] Univ Calif Berkeley, Berkeley, CA USA. [Paxson, Vern; Sornmer, Robin] Int Comp Sci Inst, Berkeley, CA USA. [Sornmer, Robin] Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Dreger, H (reprint author), Siemens AG, Corp Technol, Earlangen, Germany. FU Bavaria California Technology Center; US National Science Foundation [STI-0334088, NSF-0433702, ITR/ANI-0205519] FX We would like to thank Christian Kreibich for his feedback and the fruitful discussions that greatly helped to improve this work. We would also like to thank the Leibnitz-Rechenzentrum Munchen. This work was supported by a grant from the Bavaria California Technology Center, and by the US National Science Foundation under awards STI-0334088, NSF-0433702, and ITR/ANI-0205519, for which we are grateful. Any opinions, findings, conclusions or recommendations expressed in this material are those of the authors or originators and do not necessarily reflect the views of the National Science Foundation. NR 11 TC 6 Z9 6 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87402-7 J9 LECT NOTES COMPUT SC PY 2008 VL 5230 BP 135 EP + PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Telecommunications SC Computer Science; Telecommunications GA BIJ45 UT WOS:000260067900008 ER PT S AU Balaji, P Chan, A Gropp, W Thakur, R Lusk, E AF Balaji, P. Chan, A. Gropp, W. Thakur, R. Lusk, E. BE Lastovetsky, A Kechadi, T Dongarra, J TI Non-data-communication Overheads in MPI: Analysis on Blue Gene/P SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB Modern HEC systems, such as Blue Gene/P, rely on achieving high-performance by using the parallelism of a massive number of low-frequency/low-power processing cores. This means that the local pre- and post-communication processing required by the MPI stack might not be very fast, owing to the slow processing cores. Similarly, small amounts of serialization within the MPI stack that were acceptable on small/medium systems can be brutal on massively parallel systems. In this paper, we study different non-data-communication overheads within the MPI implementation on the IBM Blue Gene/P system. C1 [Balaji, P.; Thakur, R.; Lusk, E.] Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. [Chan, A.] Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. [Gropp, W.] Univ Illinois, Dept Comp Sci, Urbana, IL 61801 USA. RP Balaji, P (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Gropp, William/0000-0003-2905-3029 FU Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research; Office of Science; U.S. Department of Energy [DEAC02-06CH11357] FX This work was supported by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under Contract DEAC02-06CH11357. NR 9 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 13 EP + PG 3 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500001 ER PT S AU Shipman, GM Poole, S Shamis, P Rabinovitz, I AF Shipman, Galen M. Poole, Stephen Shamis, Pavel Rabinovitz, Ishai BE Lastovetsky, A Kechadi, T Dongarra, J TI X-SRQ - Improving Scalability and Performance of Multi-core InfiniBand Clusters SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB To improve the scalability of InfiniBand on large scale clusters Open MPI introduced a protocol known as B-SRQ [2]. This protocol was shown to provide much better memory utilization of send and receive buffers for a wide variety of benchmarks and real-world applications. Unfortunately B-SRQ increases the number of connections between communicating peers. While addressing one scalability problem of InfiniBand the protocol introduced another. To alleviate the connection scalability problem of the B-SRQ protocol a small enhancement to the reliable connection transport was requested which would allow multiple shared receive queues to be attached to a single reliable connection. This modified reliable connection transport is now known as the extended reliable connection transport. X-SRQ is a new transport protocol in Open MPI based on B-SRQ which takes advantage of this improvement in connection scalability. This paper introduces the X-SRQ protocol and details the significantly improved scalability of the protocol over B-SRQ and its reduction of the memory footprint of connection state by as much as 2 orders of magnitude on large scale multi-core systems. In addition to improving scalability, performance of latency-sensitive collective operations are improved by up to 38% while significantly decreasing the variability of results. A detailed analysis of the improved memory scalability as well as the improved performance are discussed. C1 [Shipman, Galen M.; Poole, Stephen] Oak Ridge Natl Lab, Oak Ridge, TN 37010 USA. [Shamis, Pavel; Rabinovitz, Ishai] Mellanox Technolo, Yokneam, Israel. RP Shipman, GM (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37010 USA. EM gshipman@ornl.gov; spoole@ornl.gov; pasha@mellanox.co.il; ishai@mellanox.co.il FU Mathematical, Information, and Computational Sciences Division; Office of Advanced Scientific Computing Research; U.S. Department of Energy [DE-AC05-00OR22725]; UT-Battelle, LLC FX Research sponsored by the Mathematical, Information, and Computational Sciences Division, Office of Advanced Scientific Computing Research, U.S. Department of Energy, under Contract No. DE-AC05-00OR22725 with UT-Battelle, LLC. NR 8 TC 2 Z9 2 U1 0 U2 3 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 33 EP + PG 3 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500003 ER PT S AU Traff, JL Ripke, A Siebert, C Balaji, P Thakur, R Gropp, W AF Traeff, Jesper Larsson Ripke, Andreas Siebert, Christian Balaji, Pavan Thakur, Rajeev Gropp, William BE Lastovetsky, A Kechadi, T Dongarra, J TI A Simple, Pipelined Algorithm for Large, Irregular All-gather Problems SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel ID ALLGATHER; NETWORKS; MPICH AB We present and evaluate a new, simple, pipelined algorithm for large, irregular all-gather problems, useful for the implementation of the MPI_Allgatherv collective operation of MPI. The algorithm can be viewed as an adaptation of a linear ring algorithm for regular all-gather problems for single-ported, clustered multiprocessors to the irregular problem. Compared to the standard ring algorithm, whose performance is dominated by the largest data size broadcast by a process (times the number of processes), the performance of the new algorithm depends only on the total amount of data over all processes. The new algorithm has been implemented within different MPI libraries. Benchmark results on NEC SX-8, Linux clusters with InfiniBand and Gigabit Ethernet, Blue Gene/P, and SiCortex systems show huge performance gains in accordance with the expected behavior. C1 [Traeff, Jesper Larsson; Ripke, Andreas; Siebert, Christian] NEC Europe Ltd, NEC Labs Europe, Rathausallee 10, D-53757 St Augustin, Germany. [Balaji, Pavan; Thakur, Rajeev] Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. [Gropp, William] Univ Illinois, Dept Comp Sci, Urbana, IL 61801 USA. RP Traff, JL (reprint author), NEC Europe Ltd, NEC Labs Europe, Rathausallee 10, D-53757 St Augustin, Germany. OI Gropp, William/0000-0003-2905-3029 FU Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research; Office of Science; U.S. Department of Energy [DE-AC02-06CH11357] FX This work was supported in part by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under Contract DE-AC02-06CH11357. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 84 EP + PG 3 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500008 ER PT S AU Brightwell, R AF Brightwell, Ron BE Lastovetsky, A Kechadi, T Dongarra, J TI A Prototype Implementation of MPI for SMARTMAP SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB Recently the Catamount lightweight kernel was extended to support direct access shared memory between processes running on the same compute node. This extension, called SMARTMAP, allows each process read/write access to another process' memory by extending the virtual address mapping. Simple virtual address bit manipulation can be used to access the same virtual address in a different process' address space. This paper describes a prototype implementation of MPI that uses SMARTMAP for intra-node message passing. SMARTMAP has several advantages over POSIX shared memory techniques for implementing MPI We present performance results comparing MPI using SMARTMAP to the existing MPI transport layer on a quad-core Cray XT platform. C1 Sandia Natl Labs, Scalable Syst Software Dept, Albuquerque, NM 87185 USA. RP Brightwell, R (reprint author), Sandia Natl Labs, Scalable Syst Software Dept, POB 5800, Albuquerque, NM 87185 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 102 EP 110 PG 9 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500010 ER PT S AU Balaji, P Buntinas, D Goodell, D Gropp, W Thakur, R AF Balaji, Pavan Buntinas, Darius Goodell, David Gropp, William Thakur, Rajeev BE Lastovetsky, A Kechadi, T Dongarra, J TI Toward Efficient Support for Multithreaded MPI Communication SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB To make the most effective use of parallel machines that are being built out of increasingly large multicore chips, researchers are exploring the use of programming models comprising a mixture of MPI and threads. Such hybrid models require efficient support from an MPI implementation for MPI messages sent from multiple threads simultaneously. In this paper, we explore the issues involved in designing such an implementation. We present four approaches to building a fully thread-safe MPI implementation, with decreasing levels of critical-section granularity (from coarse-grain locks to fine-grain locks to lock-free operations) and correspondingly increasing levels of complexity. We describe how we have structured our implementation to support all four approaches and enable one to be selected at build time. We present performance results with a message-rate benchmark to demonstrate the performance implications of the different approaches. C1 [Balaji, Pavan; Buntinas, Darius; Goodell, David; Thakur, Rajeev] Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. [Gropp, William] Univ Illinois, Dept Comp Sci, Urbana, IL 61801 USA. RP Balaji, P (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Gropp, William/0000-0003-2905-3029 FU Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research; Office of Science; U.S. Department of Energy [DEAC02-06CH11357] FX This work was supported by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under Contract DEAC02-06CH11357. We thank Sameer Kumar and others in the MPI group at IBM Research and IBM Rochester for discussions about efficient support for thread safety in MPI. NR 14 TC 7 Z9 7 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 120 EP + PG 3 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500012 ER PT S AU Graham, RL Shipman, G AF Graham, Richard L. Shipman, Galen BE Lastovetsky, A Kechadi, T Dongarra, J TI MPI Support for Multi-core Architectures: Optimized Shared Memory Collectives SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel DE Collectives; Shared-Memory; MPI_Bcast; MPI_Reduce; MPI_Allreduce AB With local core counts on the rise, taking advantage of shared-memory to optimize collective operations can improve performance. We study several on-host shared memory optimized algorithms for MPI_Bcast, MPI_Reduce, and MPI_Allreduce, using tree-based, and reduce-scatter algorithms. For small data operations with relatively large synchronization costs fan-in/fan-out algorithms generally perform best. For large messages data manipulation constitute the largest cost and reduce-scatter algorithms are best for reductions. These optimization improve performance by up to a factor of three. Memory and cache sharing effect require deliberate process layout and careful radix selection for tree-based methods. C1 [Graham, Richard L.; Shipman, Galen] Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Graham, RL (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. RI Dongarra, Jack/E-3987-2014 NR 8 TC 17 Z9 17 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 130 EP 140 PG 11 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500013 ER PT S AU Gropp, WD Kimpe, D Ross, R Thakur, R Traff, JL AF Gropp, William D. Kimpe, Dries Ross, Robert Thakur, Rajeev Traeff, Jesper Larsson BE Lastovetsky, A Kechadi, T Dongarra, J TI Self-consistent MPI-IO Performance Requirements and Expectations SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB We recently introduced the idea of self-consistent performance requirements for MPI communication. Such requirements provide a means to ensure consistent behavior of an MPI library, thereby ensuring a degree of performance portability by making it unnecessary for a user to perform implement at ion-dependent optimizations by hand. For the collective operations in particular, a large number of such rules could sensibly be formulated, without making hidden assumptions about the underlying communication system or otherwise constraining the MPI implementation. In this paper, we extend this idea to the realm of parallel I/O (MPT-IO), where the issues are far more subtle. In particular, it is not always possible to specify performance requirements without making assumptions about the implementation or without a priori knowledge of the I/O access pattern. For such cases, we introduce the notion of performance expectations, which specify the desired behavior for good implementations of MPI-IO. I/O performance requirements as well as expectations could be automatically checked by an appropriate bench-marking tool. C1 [Gropp, William D.] Univ Illinois, Dept Comp Sci, 1304 W Springfield Ave, Urbana, IL 61801 USA. [Kimpe, Dries] Katholieke Univ Leuven, Scientific Comput Res Grp, B-3001 Louvain, Belgium. [Ross, Robert; Thakur, Rajeev] Argonne Natl Lab, Mathemat & Comp Sci Div, Argonne, IL 60439 USA. [Traeff, Jesper Larsson] NEC Europe Ltd, NEC Lab Europe, D-53757 St Augustin, Germany. RP Gropp, WD (reprint author), Univ Illinois, Dept Comp Sci, 1304 W Springfield Ave, Urbana, IL 61801 USA. EM wgropp@uiuc.edu; dries.kimpe@cs.kuleuven.be; rross@mcs.anl.gov; thakur@mcs.anl.gov; traff@it.neclab.eu OI Gropp, William/0000-0003-2905-3029 FU Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research; Office of Science; U.S. Department of Energy [DE-AC02-06CH11357] FX This work was supported in part by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under Contract DE-AC02-06CH11357. NR 8 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 167 EP + PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500017 ER PT S AU Schulz, M Bronevetsky, G de Supinski, BR AF Schulz, Martin Bronevetsky, Greg de Supinski, Bronis R. BE Lastovetsky, A Kechadi, T Dongarra, J TI On the Performance of Transparent MPI Piggyback Messages SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB Many tools, including performance analysis tools, tracing libraries and application level checkpointers, add piggyback data to messages. However, transparently implementing this functionality on top of MPI is not trivial and can severely reduce application performance. We study three transparent piggyback implementations on multiple production platforms and demonstrate that all are inefficient for some application scenarios. Overall, our results show that efficient piggyback support requires mechanisms within the MPI implementation and, thus, the interface should be extended to support them. C1 [Schulz, Martin; Bronevetsky, Greg; de Supinski, Bronis R.] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Schulz, M (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 808,L-560, Livermore, CA 94551 USA. NR 7 TC 4 Z9 4 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 194 EP 201 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500020 ER PT S AU Siegel, SF Siegel, AR AF Siegel, Stephen F. Siegel, Andrew R. BE Lastovetsky, A Kechadi, T Dongarra, J TI MADRE: The Memory-Aware Data Redistribution Engine SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB A new class of algorithms is presented for efficiently carrying out many-to-many parallel data redistribution in a memory-limited environment. Key properties of these algorithms are explored, and their performance is compared using idealized benchmark problems. These algorithms form part of a newly developed MPI-based library MADRE (Memory-Aware Data Redistribution Engine), an open source toolkit designed for easy integration with application codes to improve their performance, portability, and scalability. C1 [Siegel, Stephen F.] Univ Delaware, Dept Comp & Informat Sci, Verified Software Lab, Newark, DE 19716 USA. [Siegel, Andrew R.] Argonne Natl Lab, Mathemat & Comp Sci Div, Argonne, IL 60439 USA. RP Siegel, SF (reprint author), Univ Delaware, Dept Comp & Informat Sci, Verified Software Lab, Newark, DE 19716 USA. EM siegel@cis.udel.edu; siegela@mcs.anl.gov RI Dongarra, Jack/E-3987-2014 FU National Science Foundation [CCF-0733035, CCF-0540948]; Argonne Leadership Computing Facility at Argonne National Laboratory; Office of Science of the U.S. Department of Energy [DE-AC02-06CH11357] FX This research was supported by the National Science Foundation under Grants CCF-0733035 and CCF-0540948 and used resources of the Argonne Leadership Computing Facility at Argonne National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under contract DE-AC02-06CH11357. NR 7 TC 5 Z9 5 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 218 EP + PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500023 ER PT S AU Vakkalanka, S DeLisi, M Gopalakrishnan, G Kirby, RM Thakur, R Gropp, W AF Vakkalanka, Sarvani DeLisi, Michael Gopalakrishnan, Ganesh Kirby, Robert M. Thakur, Rajeev Gropp, William BE Lastovetsky, A Kechadi, T Dongarra, J TI Implementing Efficient Dynamic Formal Verification Methods for MPI Programs SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB We examine the problem of formally verifying MPI programs for safety properties through an efficient dynamic (runtime) method in which the processes of a given MPI program are executed under the control of an interleaving scheduler. To ensure full coverage for given input test data, the algorithm must take into consideration MPI's out-of-order completion semantics. The algorithm must also ensure that nondeterministic constructs (e.g., MPI wildcard receive matches) are executed in all possible ways. Our Dew algorithm rewrites wildcard receives to specific receives, one for each sender that can potentially match with the receive. It then recursively explores each case of the specific receives. The list of potential senders matching a receive is determined through a runtime algorithm that exploits MPT's operation ordering semantics. Our verification tool ISP that incorporates this algorithm efficiently verifies several programs and finds bugs missed by existing informal verification tools. C1 [Vakkalanka, Sarvani; DeLisi, Michael; Gopalakrishnan, Ganesh; Kirby, Robert M.] Univ Utah, Sch Comp, Salt Lake City, UT 84112 USA. [Thakur, Rajeev] Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. [Gropp, William] Univ Illinois, Dept Comp Sci, Urbana, IL 61801 USA. RP Vakkalanka, S (reprint author), Univ Utah, Sch Comp, Salt Lake City, UT 84112 USA. RI Dongarra, Jack/E-3987-2014; OI Gropp, William/0000-0003-2905-3029 FU NSF [CNS-00509379]; Microsoft HPC Institutes Program; Mathematical, Information, and Computational Science Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy [DE-AC02-06CH11357] FX Supported in part by NSF CNS-00509379, Microsoft HPC Institutes Program, and the Mathematical, Information, and Computational Science Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under Contract DE-AC02-06CH11357. NR 13 TC 7 Z9 7 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 248 EP + PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500026 ER PT S AU Sharma, S Vakkalanka, S Gopalakrishnan, G Kirby, RM Thakur, R Gropp, W AF Sharma, Subodh Vakkalanka, Sarvani Gopalakrishnan, Ganesh Kirby, Robert M. Thakur, Rajeev Gropp, William BE Lastovetsky, A Kechadi, T Dongarra, J TI A Formal Approach to Detect Functionally Irrelevant Barriers in MPI Programs SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel AB We examine the unsolved problem of automatically and efficiently detecting functionally irrelevant barriers in MPI programs. A functionally irrelevant barrier is a set of MPI-Barrier calls, one per MPI process, such that their removal does not alter the overall MPI communication structure of the program. Static analysis methods are incapable of solving this problem, as MPI programs can compute many quantities at runtime, including send targets, receive sources, tags, and communicators, and also can have data-dependent control flows. We offer an algorithm called Fib to solve this problem based on dynamic (runtime) analysis. Fib applies to MPI programs that employ 24 widely used two-sided MPI operations. We show that it is sufficient to detect barrier calls whose removal causes a wildcard receive statement placed before or after a barrier to now begin matching a send statement with which it did not match before. Fib determines whether a barrier becomes relevant in any interleaving of the MPI processes of a given MPI program. Since the number of interleavings can grow exponentially with the number of processes, Fib employs a sound method to drastically reduce this number, by computing only the relevant interleavings. We show that many MPI programs do not have data dependent control flows, thus making the results of Fib applicable to all the input data the program can accept. C1 [Sharma, Subodh; Vakkalanka, Sarvani; Gopalakrishnan, Ganesh; Kirby, Robert M.] Univ Utah, Sch Comp, Salt Lake City, UT 84112 USA. [Thakur, Rajeev] Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. [Gropp, William] Univ Illinois, Dept Comp Sci, Urbana, IL 61801 USA. RP Sharma, S (reprint author), Univ Utah, Sch Comp, Salt Lake City, UT 84112 USA. RI Dongarra, Jack/E-3987-2014; OI Gropp, William/0000-0003-2905-3029 FU NSF [CNS-00509379]; Microsoft HPC Institutes Program; Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy [DE-AC02-06CH11357] FX Supported in part by NSF CNS-00509379, Microsoft HPC Institutes Program, and the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under Contract DE-AC02-06CH11357. NR 13 TC 5 Z9 5 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 265 EP + PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500028 ER PT S AU Naumann, U Hascoeat, L Hill, C Hovland, P Riehme, J Utke, J AF Naumann, Uwe Hascoeat, Laurent hill, Chris Hovland, Paul Riehme, Jan Utke, Jean BE Lastovetsky, A Kechadi, T Dongarra, J TI A Framework for Proving Correctness of Adjoint Message-Passing Programs SO RECENT ADVANCES IN PARALLEL VIRTUAL MACHINE AND MESSAGE PASSING INTERFACE SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 15th European Parallel-Virtual-Machine-and-Message-Passing-Interface-Users-Group Meeting (PVM/MPI) CY SEP 07-10, 2008 CL Dublin, IRELAND SP European Parallel Virtual Machine & Message Passing Interface Users Grp, Univ Coll Dublin, Sch Comp Sci & Informat, Sci Fdn Ireland, Microsoft, IBM, Myricom, NEC, intel ID EFFICIENT AB We propose a technique for proving correctness of adjoint message passing programs that relies on data dependences in partitioned global address space. As an example we discuss asynchronous unbuffered send/receive using MPI. C1 [Naumann, Uwe] Rhein Westfal TH Aachen, Dept Comp Sci, LuFG Informat 12, Software & Tools Computat Engn, D-52056 Aachen, Germany. [Hascoeat, Laurent] INRIA Sophia Antipolis, Projet TROPICS, Valbonne, France. [hill, Chris] MIT, Dept Earth Atmospheric & Planetary Sci, Cambridge, MA 02139 USA. [Hovland, Paul; Utke, Jean] Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL USA. [Riehme, Jan] Univ Hertfordshire, Dept Comp Sci, Hatfield, Herts, England. RP Naumann, U (reprint author), Rhein Westfal TH Aachen, Dept Comp Sci, LuFG Informat 12, Software & Tools Computat Engn, D-52056 Aachen, Germany. EM naumann@stce.rwth-aachen.de NR 16 TC 1 Z9 1 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-87474-4 J9 LECT NOTES COMPUT SC PY 2008 VL 5205 BP 316 EP + PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BII23 UT WOS:000259669500036 ER PT S AU Ellis, AR Graham, HM Sinclair, MB Verley, JC AF Ellis, A. R. Graham, H. M. Sinclair, Michael B. Verley, J. C. BE Gu, ZH Hanssen, LM TI Variable-Angle Directional Emissometer for Moderate-Temperature Emissivity Measurements SO REFLECTION, SCATTERING, AND DIFFRACTION FROM SURFACES SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Reflection, Scattering and Diffraction from Surfaces CY AUG 11-12, 2008 CL San Diego, CA SP SPIE DE emissivity; emissometer; thermal emission; reflectivity AB We have developed a system to measure the directional thermal emission from a surface, and in turn, calculate its emissivity. This approach avoids inaccuracies sometimes encountered with the traditional method for calculating emissivity, which relies upon subtracting the measured total reflectivity and total transmissivity from unity. Typical total reflectivity measurements suffer from an inability to detect backscattered light, and may not be accurate for high angles of incidence. Our design allows us to vary the measurement angle (theta) from near-normal to similar to 80 degrees, and can accommodate samples as small as 7 mm on a side by controlling the sample interrogation area. The sample mount is open-backed to eliminate shine-through, can be heated up to 200 degrees C, and is kept under vacuum to avoid oxidizing the sample. A cold shield reduces the background noise and stray signals reflected off the sample. We describe the strengths, weaknesses, trade-offs, and limitations of our system design, data analysis methods, the measurement process, and present the results of our validation of this Variable-Angle Directional Emissometer. C1 [Ellis, A. R.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ellis, AR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Verley, Jason/C-2026-2008 OI Verley, Jason/0000-0003-2184-677X NR 5 TC 4 Z9 4 U1 0 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7285-4 J9 PROC SPIE PY 2008 VL 7065 AR 706508 DI 10.1117/12.796507 PG 9 WC Instruments & Instrumentation; Optics SC Instruments & Instrumentation; Optics GA BIS51 UT WOS:000262438500004 ER PT S AU Jonsson, JC Lee, ES Rubin, M AF Jonsson, Jacob C. Lee, Eleanor S. Rubin, Mike BE Gu, ZH Hanssen, LM TI Light-scattering properties of a woven shade-screen material used for daylighting and solar heat-gain control SO REFLECTION, SCATTERING, AND DIFFRACTION FROM SURFACES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reflection, Scattering, and Diffraction from Surfaces CY AUG 11-12, 2008 CL San Diego, CA SP SPIE DE Shade screens; light scattering; ray-tracing; integrating sphere AB Shade-screens are widely used in commercial buildings as a way to limit the amount of direct sunlight that can disturb people in the building. The shade screens also reduce the solar heat-gain through glazing the system. Modern energy and daylighting analysis software such as EnergyPlus and Radiance require complete scattering properties of the scattering materials in the system. In this paper a shade screen used in the LBNL daylighting test,bed is characterized using a photogoniometer and a normal angle of incidence integrating sphere. The data is used to create a complete bi-directional scattering distribution function (BSDF) that can be used in simulation programs. The resulting BSDF is compared to a model BSDFs, both directly and by calculating the solar heat-gain coefficient for a dual pane system using Window 6. C1 [Jonsson, Jacob C.; Lee, Eleanor S.; Rubin, Mike] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Jonsson, JC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd MS70A-2255, Berkeley, CA 94720 USA. EM JCJonsson@lbl.gov NR 11 TC 3 Z9 3 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7285-4 J9 P SOC PHOTO-OPT INS PY 2008 VL 7065 AR 70650R DI 10.1117/12.795575 PG 11 WC Instruments & Instrumentation; Optics SC Instruments & Instrumentation; Optics GA BIS51 UT WOS:000262438500018 ER PT J AU Storlie, CB Helton, JC AF Storlie, Curtis B. Helton, Jon C. TI Multiple predictor smoothing methods for sensitivity analysis: Description of techniques SO RELIABILITY ENGINEERING & SYSTEM SAFETY LA English DT Review DE additive models; epistemic uncertainty; locally weighted regression; nonparametric regression; projection pursuit regression; recursive partitioning regression; scatterplot smoothing; sensitivity analysis; stepwise selection; uncertainty analysis ID PROBABILISTIC RISK-ASSESSMENT; SPATIAL POINT PATTERNS; ISOLATION PILOT-PLANT; RESPONSE-SURFACE METHODOLOGY; CONSEQUENCE UNCERTAINTY ANALYSIS; 1996 PERFORMANCE ASSESSMENT; IDENTIFY IMPORTANT FACTORS; KOLMOGOROV-SMIRNOV TEST; LARGE-SCALE SIMULATIONS; COMPUTER-MODELS AB The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described: (i) locally weighted regression (LOESS), (ii) additive models, (iii) projection pursuit regression, and (iv) recursive partitioning regression. Then, in the second and concluding part of this presentation, the indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present. (C) 2006 Elsevier Ltd. All rights reserved. C1 N Carolina State Univ, Dept Stat, Raleigh, NC 27695 USA. Arizona State Univ, Dept Math & Stat, Tempe, AZ 85287 USA. RP Helton, JC (reprint author), Sandia Natl Labs, Dept 1544, MS 0779, Albuquerque, NM 87185 USA. EM jchelto@sandia.gov RI Barley, Kamal/F-9579-2011 OI Barley, Kamal/0000-0003-1874-9813 NR 142 TC 67 Z9 67 U1 2 U2 18 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0951-8320 J9 RELIAB ENG SYST SAFE JI Reliab. Eng. Syst. Saf. PD JAN PY 2008 VL 93 IS 1 BP 28 EP 54 DI 10.1016/j.ress.2006.10.012 PG 27 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 227DI UT WOS:000250637000003 ER PT J AU Storlie, CB Helton, JC AF Storlie, Curtis B. Helton, Jon C. TI Multiple predictor smoothing methods for sensitivity analysis: Example results SO RELIABILITY ENGINEERING & SYSTEM SAFETY LA English DT Article DE additive models; epistemic uncertainty; locally weighted regression; nonparametric regression; projection pursuit regression; recursive partitioning regression; scatterplot smoothing; sensitivity analysis; stepwise selection; uncertainty analysis ID ISOLATION PILOT-PLANT; 1996 PERFORMANCE ASSESSMENT; INPUT VARIABLES; RANK CORRELATION; COMPUTER CODE; REGRESSION; UNCERTAINTY; OUTPUT; TRANSFORMATIONS AB The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described in the first part of this presentation: (i) locally weighted regression (LOESS), (ii) additive models, (iii) projection pursuit regression, and (iv) recursive partitioning regression. In this, the second and concluding part of the presentation, the indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present. (C) 2006 Elsevier Ltd. All rights reserved. C1 N Carolina State Univ, Dept Stat, Raleigh, NC 27695 USA. Arizona State Univ, Dept Math & Stat, Tempe, AZ 85287 USA. RP Helton, JC (reprint author), Sandia Natl Labs, Dept 1544, Ms 0779, Albuquerque, NM 87185 USA. EM jchelto@sandia.gov NR 31 TC 32 Z9 32 U1 1 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0951-8320 J9 RELIAB ENG SYST SAFE JI Reliab. Eng. Syst. Saf. PD JAN PY 2008 VL 93 IS 1 BP 55 EP 77 DI 10.1016/j.ress.2006.10.013 PG 23 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 227DI UT WOS:000250637000004 ER PT S AU Albin, DS AF Albin, David S. BE Dhere, NG TI Accelerated Stress Testing and Diagnostic Analysis of Degradation in CdTe Solar Cells SO RELIABILITY OF PHOTOVOLTAIC CELLS, MODULES, COMPONENTS, AND SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability of Photovoltaic Cells Modules, Components, and Systems CY AUG 11-13, 2008 CL San Diego, CA SP SPIE DE CdTe solar cell; degradation mechanism; recombination; activation energy; Kirkendall effect ID BACK-CONTACT; CU AB Solar cell module reliability is inextricably linked to cell-level reliability. This is particularly so with thin-film technologies. In CdTe, reliability issues historically associate with back contact stability and the use of Cu as an extrinsic dopant. Using a simple approach by which identical cells are heated under open-circuit bias and I-sun illumination, degradation activation energies of 0.63 and 2.94 eV in laboratory-scale CdS/CdTe devices were identified in the accelerated stress temperature range of 60 to 120 degrees C. At lower stress temperatures, cell performance changes were linearly correlated with changes in both fill factor (FF) and short-circuit current (J(sc)). At higher stress temperatures, changes in efficiency were correlated with changes in FF and open-circuit voltage (V(oc)). The measured activation energy of 0.63 is associated with Cu-diffusion. During the early stage of stress testing, which may provide additional back contact annealing, improvements in FF were due to Cu-diffusion. Decreased performance observed at longer stress times (decreased FF and V(oc)), according to a two-diode Pspice model, were due to both increased space-charge recombination (near the junction) and decreased recombination in the bulk. Kirkendall void formation (S-outdiffusion) at the CdS/CdTe interface is given as responsible for the 2.9 eV degradation mechanism. C1 Natl Renewable Energy Lab, Denver, CO 80401 USA. RP Albin, DS (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Denver, CO 80401 USA. NR 19 TC 6 Z9 6 U1 0 U2 9 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7268-7 J9 P SOC PHOTO-OPT INS PY 2008 VL 7048 AR 70480N DI 10.1117/12.795360 PG 10 WC Energy & Fuels; Instruments & Instrumentation; Optics SC Energy & Fuels; Instruments & Instrumentation; Optics GA BIT48 UT WOS:000262507800020 ER PT S AU Emery, K AF Emery, K. BE Dhere, NG TI PV reliability determination from I-V measurement and analysis SO RELIABILITY OF PHOTOVOLTAIC CELLS, MODULES, COMPONENTS, AND SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability of Photovoltaic Cells Modules, Components, and Systems CY AUG 11-13, 2008 CL San Diego, CA SP SPIE DE Efficiency; solar cell; photovoltaic ID PERFORMANCE; MODULES AB We discuss the measurement and analysis of current vs. voltage (I-V) characteristics of photovoltaic (PV) cells and modules for reliability determination. We discuss both the error sources in the measurements and the strategies to minimize their influence. These error sources include the sample area, spectral errors, temperature fluctuations, current and voltage response time, contacting, and degradation during testing issues. Information that can be extracted from light and dark I-V includes peak power, open-circuit voltage, short-circuit current, series and shunt resistance, diode quality factor, dark current, and photo-current. The quantum efficiency provides information on photo-current nonlinearities, current generation and recombination mechanisms. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Emery, K (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 21 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7268-7 J9 P SOC PHOTO-OPT INS PY 2008 VL 7048 AR 704803 DI 10.1117/12.795965 PG 7 WC Energy & Fuels; Instruments & Instrumentation; Optics SC Energy & Fuels; Instruments & Instrumentation; Optics GA BIT48 UT WOS:000262507800004 ER PT S AU Kempe, MD Thapa, P AF Kempe, Michael D. Thapa, Prem BE Dhere, NG TI Low Cost, Single Layer Replacement for the Back-sheet and Encapsulant Layers SO RELIABILITY OF PHOTOVOLTAIC CELLS, MODULES, COMPONENTS, AND SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability of Photovoltaic Cells Modules, Components, and Systems CY AUG 11-13, 2008 CL San Diego, CA SP SPIE AB Ethylene propylene diene monomer (EPDM) based polymers have been formulated for specific use in photovoltaic modules to produce better performance and longer term stability at a lower cost than standard materials. EPDM formulations are advantageous over ethylene vinyl-acetate (EVA) because they can use the same lamination/cure cycle as EVA, they do not need a second back-sheet protective material (e.g. PET/Tedlar), they have a lower glass transition temperature, no melting transition, more constant mechanical moduli as a function of temperature, they are less polar than EVA (provides better corrosion protection), and they have excellent damp heat (85 degrees C/85% relative humidity) resistance against delamination. Module designs typically use EVA on the back side of cells despite the fact that transparency is not advantageous. We have developed a single encapsulant layer that will replace standard module back-sheet constructions consisting of EVA/PET/Tedlar. Because a single low-cost material layer is used, it will provide a significant materials cost savings of about $6 to $8/m(2) as compared to traditional back-sheets. Electrical insulation tests were conducted using 0.85 mm, thick stainless steel sheets as a model for a cell. It was found that a polymer layer thickness of about 0.33mm provided better high voltage electrical insulation than a combined film of Tedlar (TM) (0.038 mm) / PET (0.051 mm) / EVA (0.55 mm). When formulated with a white pigment, reflectivity was comparable to Tedlar (TM). Upon accelerated exposure to light at 60C and 60% RH it was found that an EVA layer in front of these materials would decompose before significant yellowing and delamination of the back EPDM layer occurs. C1 [Kempe, Michael D.] Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kempe, MD (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 9 TC 1 Z9 1 U1 0 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7268-7 J9 P SOC PHOTO-OPT INS PY 2008 VL 7048 AR 70480D DI 10.1117/12.795413 PG 12 WC Energy & Fuels; Instruments & Instrumentation; Optics SC Energy & Fuels; Instruments & Instrumentation; Optics GA BIT48 UT WOS:000262507800013 ER PT S AU Olsen, LC Gross, ME Graff, GL Kundu, SN AF Olsen, L. C. Gross, M. E. Graff, G. L. Kundu, S. N. BE Dhere, NG TI Approaches to Encapsulation of Flexible CIGS Cells SO RELIABILITY OF PHOTOVOLTAIC CELLS, MODULES, COMPONENTS, AND SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability of Photovoltaic Cells Modules, Components, and Systems CY AUG 11-13, 2008 CL San Diego, CA SP SPIE DE Encapsulation; CIGS; solar cell; thin-film; BIPV; barrier coating; flexible ID FILMS AB Thin-film solar cells based on CIGS are being considered for large scale power plants as well as building integrated photovoltaic (BIPV) applications. Past studies indicate that CIGS cells degrade rapidly when exposed to moisture. As a result, an effective approach to encapsulation is required for CIGS cells to satisfy the international standard IEC 61646. CIGS modules fabricated for use in large power plants can be encapsulated with glass sheets on the top and bottom surfaces and can be effectively sealed around the edges. In the case of BIPV applications, however, it is desirable to utilize CIGS cells grown on flexible substrates, both for purposes of achieving reduced weight and for cases involving non-flat surfaces. For these cases, approaches to encapsulation must be compatible with the flexible substrate requirement. Even in the case of large power plants, the glass-to-glass approach to encapsulation may eventually be considered too costly. We are investigating encapsulation of flexible CIGS cells by lamination. Sheets of PET or PEN coated with multilayer barrier coatings are used to laminate the flexible cells. Results are discussed for laminated cells from two CIGS manufacturers. In both cases, the cell efficiency decreases less than 10% after 1000 hours of exposure to an environment of 85 degrees C/85%RH. This paper discusses these two approaches, and reviews results for uncoated cells and mini-modules fabricated by the former Shell Solar Industries (SSI). C1 [Olsen, L. C.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Olsen, LC (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd, Richland, WA 99352 USA. NR 5 TC 0 Z9 0 U1 2 U2 11 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7268-7 J9 P SOC PHOTO-OPT INS PY 2008 VL 7048 AR 70480O DI 10.1117/12.796104 PG 8 WC Energy & Fuels; Instruments & Instrumentation; Optics SC Energy & Fuels; Instruments & Instrumentation; Optics GA BIT48 UT WOS:000262507800021 ER PT S AU Pern, FJ Noufi, R To, B DeHart, C Li, X Glick, SH AF Pern, F. J. Noufi, R. To, B. DeHart, C. Li, X. Glick, S. H. BE Dhere, NG TI Degradation of ZnO-based window layers for thin-film CIGS by accelerated stress exposures SO RELIABILITY OF PHOTOVOLTAIC CELLS, MODULES, COMPONENTS, AND SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability of Photovoltaic Cells Modules, Components, and Systems CY AUG 11-13, 2008 CL San Diego, CA SP SPIE DE transparent conducting oxides; intrinsic and Al-doped ZnO; ZnMgO alloy; accelerated exposure; damp heat; weatherometer; degradation; CIGS; thin-film solar cell ID TRANSPARENT CONDUCTING OXIDES; SOLAR-CELL; BAND-GAP; DEPOSITION AB The reliability of ZnO-based window layer for CuInGaSe(2) (CIGS) solar cells was investigated. Samples of RF magnetron-sputtered, single-layer intrinsic and Al-doped ZnO and their combined bilayer on glass substrates were exposed in a weatherometer (WOM) and damp heat (DH) conditions with or without acetic acid vapor. Some preliminary samples of single-layer Al-doped Zn(1-x)Mg(x)O (ZMO) alloy, a potential replacement for Al:ZnO with a wider bandgap, were also evaluated in the DH. The Al-doped ZnO and ZMO films showed irreversible loss in the conducting properties, free carrier mobility, and characteristic absorption band feature after <500-h DH exposure, with the originally clear transparent films turned into white hazy insulating films and the degradation rate follows the trend of (DH + acetic acid) > DH > WOM. The degradation rate was also reduced by higher film thickness, higher deposition substrate temperature, and dry-out intervals. The results of X-ray diffraction analysis indicate that the ZnO-based films underwent structural degeneration by losing their highly (002) preferential orientation with possible transformation from hexagonal into cubic and formation of Zn(OH)(2). Periodic optical micro-imaging observations suggested a temporal process that involves initial hydrolysis of the oxides at sporadic weak spots, swelling and popping of the hydrolyzed spots due to volume increase, segregation of hydrolyzed regions causing discontinuity of electrical path, hydrolysis of the oxide-glass interface, and finally, formation of insulating oxides/hydroxides with visible delamination over larger areas. C1 [Pern, F. J.; To, B.; DeHart, C.; Li, X.; Glick, S. H.] NREL, NCPV, Golden, CO 80401 USA. RP Pern, FJ (reprint author), NREL, NCPV, 1617 Cole Blvd, Golden, CO 80401 USA. NR 39 TC 8 Z9 8 U1 1 U2 10 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7268-7 J9 P SOC PHOTO-OPT INS PY 2008 VL 7048 AR 70480P DI 10.1117/12.795097 PG 14 WC Energy & Fuels; Instruments & Instrumentation; Optics SC Energy & Fuels; Instruments & Instrumentation; Optics GA BIT48 UT WOS:000262507800022 ER PT S AU Swiler, TP Krishnamoorthy, U Clews, PJ Baker, MS Tanner, DM AF Swiler, Thomas P. Krishnamoorthy, Uma Clews, Peggy J. Baker, Michael S. Tanner, Danelle M. BE Hartzell, AL Ramesham, R TI Challenges of designing and processing extreme low-G micro electrical-mechanical system (MEMS) accelerometers - art. no. 68840O SO RELIABILITY, PACKAGING, TESTING, AND CHARACTERIZATION OF MEMS/MOEMS VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Reliability, Packaging, Testing, and Characterization of MEMS/MOEMS VII CY JAN 21-22, 2008 CL San Jose, CA SP SPIE, Boston Univ, Photon Ctr DE MEMS; nano-G; accelerometer; sub-wavelength grating; MEMS packaging; MEMS release ID YB-YAG; LASER AB There is an increasing demand to build highly sensitive, low-G, microscale acceleration sensors with the ability to sense accelerations in the nano-G (10(-8) m/s(2)) regime. To achieve such sensitivities, these sensors require compliant mechanical springs attached to large masses. The high sensitivities and the difficulty in integrating robust mechanical stops into these designs make these parts inherently weak, lacking the robustness to survive even the low level accelerations encountered in standard handling, from release processing, where supporting interlayers present during fabrication are etched away, through packaging. Thus, the process of transforming a MEMS-based acceleration sensor from an unreleased state to a protected functional state poses significant challenges. We summarize prior experiences with packaging such devices and report on recent work in packaging and protecting a highly sensitive acceleration sensor that optically senses displacement through the use of sub-wavelength nanogratings. We find that successful implementation of such sensors requires starting with a clean and robust MEMS design, performing careful and controlled release processing, and designing and executing a robust handling and packaging solution that keeps a fragile MEMS device protected at all times. C1 [Swiler, Thomas P.; Krishnamoorthy, Uma; Clews, Peggy J.; Baker, Michael S.; Tanner, Danelle M.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Swiler, TP (reprint author), Sandia Natl Labs, POB 5800,MS 0959, Albuquerque, NM 87185 USA. NR 22 TC 1 Z9 1 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7059-1 J9 P SOC PHOTO-OPT INS PY 2008 VL 6884 BP O8840 EP O8840 DI 10.1117/12.778244 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics SC Engineering; Science & Technology - Other Topics; Optics GA BHS41 UT WOS:000255942000021 ER PT S AU Chatterji, S Yamazaki, I Bai, ZJ Eisen, JA AF Chatterji, Sourav Yamazaki, Ichitaro Bai, Zhaojun Eisen, Jonathan A. BE Vingron, M Wong, L TI CompostBin: A DNA composition-based algorithm for binning environmental shotgun reads SO RESEARCH IN COMPUTATIONAL MOLECULAR BIOLOGY, PROCEEDINGS SE Lecture Notes in Bioinformatics LA English DT Proceedings Paper CT 12th Annual International Conference on Research Computational Molecular Biology CY MAR 30-APR 02, 2008 CL Singapore, SINGAPORE SP Natl Univ Singapore, NUS Bioinformat Programme, Lilly, IBM, ISCB, World Sci, Taylor & Francis DE metagenomics; binning; feature extraction; normalized cut; weighted PCA; DNA composition metrics; genome signatures ID MICROBIAL COMMUNITIES; METAGENOMIC ANALYSIS; GENOMES; BACTERIAL; FRAGMENTS AB A major hindrance to studies of microbial diversity has been that the vast majority of microbes cannot be cultured in the laboratory and thus are not amenable to traditional methods of characterization. Environmental shotgun sequencing (ESS) overcomes this hurdle by sequencing the DNA from the organisms present in a. microbial community. The interpretation of this metagenomic data can be greatly facilitated by associating every sequence read with its source organism. We report the development of CompostBin, a DNA composition-based algorithm for analyzing metagenomic sequence reads and distributing them into taxon-specific bins. Unlike previous methods that seek to bin assembled contigs and often require training on known reference genomes, CompostBin has the ability to accurately bin raw sequence reads without need for assembly or training. CompostBin uses a novel weighted PCA algorithm to project the high dimensional DNA composition data into an informative lower-dimensional space, and then uses the normalized cut clustering algorithrn on this filtered data set to classify sequences into taxon-specific bins. We demonstrate the algorithm's accuracy on a variety of low to medium complexity data sets. C1 [Chatterji, Sourav; Eisen, Jonathan A.] Univ Calif Davis, Genome Ctr, Davis, CA 95616 USA. [Yamazaki, Ichitaro; Bai, Zhaojun] U C Davis, Comp Sci Dept, Davis, CA 95616 USA. [Eisen, Jonathan A.] Joint Genome Inst, Walnut Creek, CA 94598 USA. RP Chatterji, S (reprint author), Univ Calif Davis, Genome Ctr, Davis, CA 95616 USA. EM schatterji@ucdavis.edu; yamazaki@cs.udavis.edu; bai@cs.ucdavis.edu; jaeisen@ucdavis.edu FU Laboratory Directed Research and Development Program (Lawrence Berkeley Lab); Defense Advanced Research Projects Agency [HR0011-05-1-0057, FA9550-06-1-0478]; NSF [0313390] FX We thank Ambuj Tewari, Martin Wu, Lior Pachter, Jonathan Dushoff, Joshua Weitz, Dongying Wu, Amber Hartman, and Jenna Morgan for their helpful suggestions and comments. This work was supported in part by a Laboratory Directed Research and Development Program (Lawrence Berkeley Lab) Grant to Jonathan A. Eisen. S.C. and J.E. were partially supported by the Defense Advanced Research Projects Agency under grants HR0011-05-1-0057 and FA9550-06-1-0478. I.Y. and Z.B. were supported in part by the NSF under grant 0313390. NR 26 TC 38 Z9 41 U1 0 U2 15 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-78838-6 J9 LECT N BIOINFORMAT JI Lect. Notes Bioinforma. PY 2008 VL 4955 BP 17 EP + PG 3 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Computer Science, Information Systems; Mathematical & Computational Biology; Mathematics, Applied SC Biochemistry & Molecular Biology; Computer Science; Mathematical & Computational Biology; Mathematics GA BHM89 UT WOS:000254391500002 ER PT J AU Stringer, S AF Stringer, Steve TI Connecting business needs with basic science SO RESEARCH-TECHNOLOGY MANAGEMENT LA English DT Editorial Material C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Stringer, S (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87544 USA. EM stringer@lanl.gov NR 6 TC 0 Z9 0 U1 0 U2 1 PU INDUSTRIAL RESEARCH INST, INC PI ARLINGTON PA 2200 CLARENDON BLVD, STE 1102, ARLINGTON, VA 22201 USA SN 0895-6308 J9 RES TECHNOL MANAGE JI Res.-Technol. Manage. PD JAN-FEB PY 2008 VL 51 IS 1 BP 9 EP 14 PG 6 WC Business; Engineering, Industrial; Management SC Business & Economics; Engineering GA 247WN UT WOS:000252113400004 ER PT S AU Madaras, EI Anastasi, RF Seebo, JP Studor, G McMakin, DL Nellums, R Winfiree, WP AF Madaras, Eric I. Anastasi, Robert F. Seebo, Jeffrey P. Studor, George McMakin, Douglas L. Nellums, Robert Winfiree, William P. BE Thompson, DO Chimenti, DE TI The potential for imaging in situ damage in inflatable space structures SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE terahertz imaging; millimeter wave imaging; microwave imaging; space NDE; inflatable space structures AB NASA is investigating the use of inflatable habitat structures for orbital transfer and planetary applications. Since space structures are vulnerable to damage from micrometeoroid and orbital debris, it is important to investigate means of detecting such damage. This study is an investigation into methods for performing non-destructive evaluation (NDE) on inflatable habitat modules. Results of this work showed that various electromagnetic imaging modalities from microwaves to terahertz imaging have the greatest potential for a viable, portable, NDE tool which could possibly be deployed aboard an inflatable habitat module. C1 [Madaras, Eric I.; Winfiree, William P.] NASA, Langley Res Ctr, Nondestruct Evaluat Sci Branch, MS 231, Hampton, VA 23681 USA. [Anastasi, Robert F.] NASA, Langley Res Ctr, Nondestruct Evaluat Sci Branch, US Army Res Lab,Vehicle Technol, Hampton, VA 23681 USA. [Seebo, Jeffrey P.] NASA, Langley Res Ctr, Lockheed Martin, Hampton, VA 23681 USA. [Studor, George] NASA, Johnson Space Ctr, Struct Branch, Houston, TX USA. [McMakin, Douglas L.] Pacif Northwest Natl Lab, Appl Phys, Richland, WA 99354 USA. [Nellums, Robert] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Madaras, EI (reprint author), NASA, Langley Res Ctr, Nondestruct Evaluat Sci Branch, MS 231, Hampton, VA 23681 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 437 EP + PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553700055 ER PT S AU Sun, JG AF Sun, J. G. BE Thompson, DO Chimenti, DE TI Thermal imaging analysis of material structures and defects SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE thermal imaging; numerical simulation; material structure; defect ID DIFFUSIVITY AB A numerical one-dimensional (1D) heat-transfer model was developed to simulate the surface temperature response under one-sided pulsed thermal imaging for plate samples with internal material variations including different optical and thermal properties, multilayer structures, and defect distributions (delaminations). The simulation results showed the complexity and subtle differences of the thermal imaging response to the material variations. With further development in data processing technologies, it is expected that thermal imaging may be used to detect and predict these material property variations. C1 Argonne Natl Lab, Nucl Engn Div, Argonne, IL 60439 USA. RP Sun, JG (reprint author), Argonne Natl Lab, Nucl Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 528 EP 535 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553700067 ER PT S AU Goulding, NR MarqueZ, JD Prewett, EM Claytor, TN Nadler, BR AF Goulding, N. R. Marquez, J. D. Prewett, E. M. Claytor, T. N. Nadler, B. R. BE Thompson, DO Chimenti, DE TI Ultrasonic imaging techniques for breast cancer detection SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE breast cancer ultrasonic imaging; ultrasonic breast Imaging ID TOMOGRAPHY; MIGRATION AB Improving the resolution and specificity of current ultrasonic imaging technology is needed to enhance its relevance to breast cancer detection. A novel ultrasonic imaging reconstruction method is described that exploits classical straight-ray migration. This novel method improves signal processing for better image resolution and uses novel staging hardware options using a pulse-echo approach. A breast phantom with various inclusions is imaged using the classical migration method and is compared to standard computed tomography (CT) scans. These innovative ultrasonic methods incorporate ultrasound data acquisition, beam profile characterization, and image reconstruction. For an ultrasonic frequency of 2.25 MHz, imaged inclusions of approximately 1 cm are resolved and identified. Better resolution is expected with minor modifications. improved image quality and resolution enables earlier detection and more accurate diagnoses of tumors thus reducing the number of biopsies performed, increasing treatment options, and lowering remission percentages. Using these new techniques the inclusions in the phantom are resolved and compared to the results of standard methods. Refinement of this application using other imaging techniques such as time-reversal mirrors (TRM), synthetic aperture focusing technique (SAFT), decomposition of the time reversal operator (DORT), and factorization methods is also discussed. C1 [Goulding, N. R.] New Mexico Inst Min & Technol, Dept Elect Engn & Comp Sci, Socorro, NM 87801 USA. [Marquez, J. D.] Univ Texas Austin, Dept Mech Engn, Austin, TX 78712 USA. [Prewett, E. M.] Purdue Univ, Dept Mech Engn, W Lafayette, IN 47907 USA. [Claytor, T. N.; Nadler, B. R.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Goulding, NR (reprint author), New Mexico Inst Min & Technol, Dept Elect Engn & Comp Sci, Socorro, NM 87801 USA. FU Los Alamos Dynamics Summer School of the Engineering Sciences Division at Los Alamos National Laboratory FX The authors thank Nebojsa Duric (Karmanos Cancer Institute) and Lianjie Huang (Los Alamos National Laboratory) for their advice regarding the experimental procedure and algorithm methods discussed in this paper. The authors also thank HYTEC Incorporated for performing the computed tomography scans. The authors acknowledge the funding and support of the Los Alamos Dynamics Summer School of the Engineering Sciences Division at Los Alamos National Laboratory. The authors also recognize The MathWorks, Inc. for their generous donation of MATLAB software that was used to perform all data analysis and image reconstruction. NR 18 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 656 EP + PG 3 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553700083 ER PT S AU Davis, WB AF Davis, William B. BE Thompson, DO Chimenti, DE TI Predicting spot weld button area with an ultrasonic phased array SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE spot weld inspection; ultrasonic phased array; signal and image processing; quality prediction AB In automobile manufacturing, the quality of spot welds joining thin mild steel sheets is assessed primarily by the diameter of the button remaining after destructive teardown, relative to the thickness of the sheets. To facilitate a comparison with destructive testing, several features of ultrasonic images of spot welds were assessed for their ability to predict weld button area. An experiment was performed in which representative weld test coupons were imaged with a prototype portable, hand-held phased array system, and then tom down destructively and their buttons measured. Features of the ultrasonic images were examined for their ability to predict the corresponding button areas. These features included: transmissive area; a frequency ratio proxy for reflectivity; and dimensions of the surface indentation caused by the welding electrode. Regression models with these explanatory variables predicting button area all achieve 95% or better fits. Button diameters were predicted with 95% confidence to an accuracy of 2-4 times the pitch of the array. These results indicate that the ultrasonic measurement system is sufficiently accurate for weld quality assessment. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Davis, WB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 46A-1123B, Berkeley, CA 94720 USA. NR 1 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 731 EP 738 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553700092 ER PT S AU Hopkins, DL AF Hopkins, Deborah L. BE Thompson, DO Chimenti, DE TI Use of metallographic analysis and strength testing to improve ultrasonic phased-array evaluation of resistance spot welds SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE ultrasonic phased array; resistance spot weld; strength testing; metallography; metallurgy AB Results are summarized for a series of experiments in which one hundred spot welds were inspected using a high-frequency phased-array ultrasonic probe, and then sectioned, polished and etched to reveal the microstructure of the welds. The ultrasonic and metallographic results are analyzed in conjunction with the results of strength tests and the size of the weld buttons obtained from destructive tear-down of the welded samples. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Hopkins, DL (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 1042 EP 1049 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553701017 ER PT S AU Quarry, MJ AF Quarry, M. J. BE Thompson, DO Chimenti, DE TI Horizontal shear wave imaging of large optics SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE structural health monitoring; horizontal shear waves; laser damage ID DAMAGE AB When complete the National Ignition Facility (NIF) will be the world's largest and most energetic laser and will be capable of achieving for the first time fusion ignition in the laboratory. Detection of damage features on optical surfaces within the laser beamlines and sizing them at diameters of 0. 1 mm to 10 mm allows timely decisions concerning refurbishment and will help with the routine operation of the system. Horizontally polarized shear waves at 10 MHz were shown to accurately detect, locate, and size features created by laser operations from 0.5 mm. to 8 nun by placing sensors at the edge of the optic. The shear wave technique utilizes highly directed beams. The outer edge of an optic can be covered with shear wave transducers on four sides. Each transducer sends a pulse into the optic and any damage reflects the pulse back to the transmitter. The transducers are multiplexed, and the collected time waveforms are enveloped and replicated across the width of the element. Multiplying the matrix data sets from four directions produces a map of reflected amplitude to the fourth power, which images the surface of the optic. Surface area can be measured directly from the image, and maximum depth was shown to be correlated to maximum amplitude of the reflected waveform. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Quarry, MJ (reprint author), Lawrence Livermore Natl Lab, 7000 E Ave, Livermore, CA 94550 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 1461 EP 1467 PG 7 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553701072 ER PT S AU Anderson, BE Scalerandi, M Gliozzi, AS Griffa, M Ulrich, TJ Johnson, PA AF Anderson, Brian E. Scalerandi, Marco Gliozzi, Antonio S. Griffa, Michele Ulrich, T. J. Johnson, Paul A. BE Thompson, DO Chimenti, DE TI Selective source reduction to identify masked smaller sources using Time Reversed Acoustics (TRA) SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE time reversal; Time Reversed Acoustics; crack detection; source characterization ID ULTRASONIC PULSES; PROPAGATION; SIMULATION; SOLIDS AB This paper introduces a method to selectively reduce large time-reversed focal events to provide the potential to illuminate smaller events which have been masked by the larger one. The method is demonstrated for two elastic wave pulses emitted simultaneously from two spatially separated sources. The method improves upon the spatial resolution abilities of time reversed acoustics in nondestructive evaluation applications to identify characteristics of a sample such as cracks (nonlinear elastic wave scattering sources). C1 [Anderson, Brian E.; Griffa, Michele; Ulrich, T. J.; Johnson, Paul A.] Los Alamos Natl Lab, Geophys Grp, MS D443, Los Alamos, NM 87544 USA. [Scalerandi, Marco; Gliozzi, Antonio S.] Politecn Torino, CNISM, Dept Phys, I-10129 Turin, Italy. RP Anderson, BE (reprint author), Los Alamos Natl Lab, Geophys Grp, MS D443, Los Alamos, NM 87544 USA. EM bea@lanl.gov; tju@lanl.gov RI Anderson, Brian/G-8819-2012; OI GLIOZZI, ANTONIO/0000-0003-1084-0444; SCALERANDI, MARCO/0000-0003-0809-9976 FU Los Alamos National Laboratory; European Community through the project AERONEWS FX This research was supported by institutional support (LDRD) at the Los Alamos National Laboratory and by the European Community through the project AERONEWS. NR 14 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 1520 EP + PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553701080 ER PT S AU Claytor, TN Torney, RK AF Claytor, T. N. Torney, R. K. BE Thompson, DO Chimenti, DE TI Optimization of high sensitivity ultrasonic scanning SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOL 27A AND 27B SE AIP Conference Proceedings LA English DT Proceedings Paper CT 34th Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 22-27, 2007 CL Golden, CO SP QNDE Programs DE 12-bit waveform digitizer; high speed digitizer; ultrasonic imaging; ultrasonic scanning AB Finer amplitude resolution provided by high-speed 12-bit waveform digitizers can potentially reveal more about materials and assemblies than could be previously detected, though the increased resolution makes effects not apparent with 8-bit digitizers noticeable. If not recognized and minimized, these effects can eliminate any potential increase in sensitivity gained by using a 12-bit board. We test, characterize, and compare 8- and 12-bit digitizer boards from three suppliers suitable for use in ultrasonic imaging. We measure trigger jitter, amplitude variability, and intrinsic noise level for each board as a function of several variables. Our results allow us to optimize image quality given various constraints inherent in continuous waveform capture imaging. An ultrasonic scan of an item with a low contrast feature illustrates the difference between imaging with an 8-bit board and a 12-bit board. C1 [Claytor, T. N.] Los Alamos Natl Lab, AET-6,MS C914, Los Alamos, NM 87545 USA. [Torney, R. K.] Stanford Univ, Dept Human Biol, Stanford, CA 94305 USA. RP Claytor, TN (reprint author), Los Alamos Natl Lab, AET-6,MS C914, Los Alamos, NM 87545 USA. EM claytor@lanl.gov; rtorney@lanl.gov NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0494-6 J9 AIP CONF PROC PY 2008 VL 975 BP 1559 EP + PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA BHN68 UT WOS:000254553701085 ER PT J AU Ao, T Asay, JR Chantrenne, S Baer, MR Hall, CA AF Ao, T. Asay, J. R. Chantrenne, S. Baer, M. R. Hall, C. A. TI A compact strip-line pulsed power generator for isentropic compression experiments SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID SHOCK-WAVE EXPERIMENTS; SANDIA Z-ACCELERATOR; INTERFEROMETER; ALUMINUM; SAPPHIRE; SOLIDS; IMPACT; ICE; GPA AB Veloce is a medium-voltage, high-current, compact pulsed power generator developed for isentropic and shock compression experiments. Because of its increased availability and ease of operation, Veloce is well suited for studying isentropic compression experiments (ICE) in much greater detail than previously allowed with larger pulsed power machines such as the Z accelerator. Since the compact pulsed power technology used for dynamic material experiments has not been previously used, it is necessary to examine several key issues to ensure that accurate results are obtained. In the present experiments, issues such as panel and sample preparation, uniformity of loading, and edge effects were extensively examined. In addition, magnetohydrodynamic simulations using the ALEGRA code were performed to interpret the experimental results and to design improved sample/panel configurations. Examples of recent ICE studies on aluminum are presented. (c) 2008 American Institute of Physics. C1 [Ao, T.; Asay, J. R.; Baer, M. R.; Hall, C. A.] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Chantrenne, S.] Ktech Corp Inc, Albuquerque, NM 87123 USA. RP Ao, T (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 59 TC 44 Z9 50 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2008 VL 79 IS 1 AR 013903 DI 10.1063/1.2827509 PG 16 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 257TQ UT WOS:000252821800032 PM 18248046 ER PT J AU Cornell, E Fisher, WW Nordmeyer, R Yegian, D Dong, M Biggin, MD Celniker, SE Jin, J AF Cornell, E. Fisher, W. W. Nordmeyer, R. Yegian, D. Dong, M. Biggin, M. D. Celniker, S. E. Jin, J. TI Automating fruit fly Drosophila embryo injection for high throughput transgenic studies SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID GENOME AB To decipher and manipulate the 14000 identified Drosophila genes, there is a need to inject a large number of embryos with transgenes. We have developed an automated instrument for high throughput injection of Drosophila embryos. It was built on an inverted microscope, equipped with a motorized xy stage, autofocus, a charge coupled device camera, and an injection needle mounted on a high speed vertical stage. A novel, micromachined embryo alignment device was developed to facilitate the arrangement of a large number of eggs. The control system included intelligent and dynamic imaging and analysis software and an embryo injection algorithm imitating a human operator. Once the injection needle and embryo slide are loaded, the software automatically images and characterizes each embryo and subsequently injects DNA into all suitable embryos. The ability to program needle flushing and monitor needle status after each injection ensures reliable delivery of biomaterials. Using this instrument, we performed a set of transformation injection experiments. The robot achieved injection speeds and transformation efficiencies comparable to those of a skilled human injector. Because it can be programed to allow injection at various locations in the embryo, such as the anterior pole or along the dorsal or ventral axes, this system is also suitable for injection of general biochemicals, including drugs and RNAi. (C) 2008 American Institute of Physics. C1 [Cornell, E.; Nordmeyer, R.; Yegian, D.; Jin, J.] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, Berkeley, CA 94720 USA. [Fisher, W. W.; Celniker, S. E.] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. [Dong, M.; Biggin, M. D.] Univ Calif Berkeley, Lawrence Berkeley Lab, Genom Div, Berkeley, CA 94720 USA. RP Cornell, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [R01 GM070444] NR 14 TC 6 Z9 6 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2008 VL 79 IS 1 AR 013705 DI 10.1063/1.2827516 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 257TQ UT WOS:000252821800023 PM 18248037 ER PT J AU Hansen, JF Glendinning, SG Heeter, RF Brockington, SJE AF Hansen, J. F. Glendinning, S. G. Heeter, R. F. Brockington, S. J. E. TI Dynamic Hohlraums as x-ray sources in high-energy density science SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ABSORPTION FINE-STRUCTURE AB The first demonstration of laser driven dynamic Hohlraums (LDDH) as a spectrally smooth backlighter source for opacity and temperature measurements through absorption spectrometry of materials in local thermodynamic equilibrium at temperatures >150 eV has been made. This is a crucial temperature regime for future astrophysics and ignition fusion experiments at the nearly completed National Ignition Facility (NIF) [E. I. Moses and C. R. Wuest, Fusion Sci. Technol. 47, 314 (2005)] at the Lawrence Livermore National Laboratory. The new backlighter consists of a LDDH filled with either krypton or argon that implodes to create an x-ray flash. The properties of this x-ray flash have been measured in experiments at the Omega laser [T. R. Boehly , Opt. Commun. 133, 495 (1997)] at the Laboratory for Laser Energetics in Rochester, New York, satisfying all requirements imposed by future experiments: (1) the emission spectrum extends to at least 5.5 keV, well above the maximum x-ray energy (similar to 3.5 keV) obtained from the previously "best" opacity backlighters (uranium M-shell emission backlighters); (2) the spectrum is smooth and featureless (intensity variation < 6% rms), allowing absorption spectrometry through experimental samples; (3) the emission source size is sufficiently small (< 50 mu m) for projection backlighting through future samples; (4) the emission is bright enough (and twice as bright as imploding hydrogen-filled capsules) for gated spectrometer measurements; (5) the emission duration is optimized (approximate to 100 ps) for the current and future generations of spectrometers; and (6) by using only a small number of beams with limited energy and symmetry for the backlighter (10 out of 60 beams in the Omega experiments), the majority of laser beams are left available for heating sample materials to >150 eV. (C) 2008 American Institute of Physics. C1 [Hansen, J. F.; Glendinning, S. G.; Heeter, R. F.; Brockington, S. J. E.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Hansen, JF (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 17 TC 11 Z9 11 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2008 VL 79 IS 1 AR 013504 DI 10.1063/1.2804765 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 257TQ UT WOS:000252821800017 PM 18248031 ER PT J AU Lee, SG Bak, JG Bitter, M AF Lee, S. G. Bak, J. G. Bitter, M. TI Calibration of an imaging crystal spectrometer for low x-ray energies SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID SPECTROSCOPY; TEMPERATURE; TUBE; MICA; ION AB An x-ray imaging crystal spectrometer was designed for the Hanbit magnetic mirror device to observe spectra of heliumlike neon at 13.4474 angstrom. The spectrometer consists of a spherically bent mica crystal and an x-ray sensitive vacuum charge coupled device camera. This spectrometer can provide spatially resolved spectra, making it possible to obtain profiles of the ion charge state distribution from line ratios and profiles of the plasma rotation velocity from Doppler shift measurements. The paper describes measurements of spectral resolution of this instrument for low x-ray energies. (C) 2008 American Institute of Physics. C1 [Lee, S. G.; Bak, J. G.] Natl Fus Res Inst, Taejon 305333, South Korea. [Bitter, M.] Princeton Plasma Phys Lab, Princeton, NJ 08540 USA. RP Lee, SG (reprint author), Natl Fus Res Inst, Taejon 305333, South Korea. EM sglee@nfri.re.kr NR 13 TC 3 Z9 3 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2008 VL 79 IS 1 AR 013501 DI 10.1063/1.2829888 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 257TQ UT WOS:000252821800014 PM 18248028 ER PT J AU Medley, SS Donne, AJH Kaita, R Kislyakov, AI Petrov, MP Roquemore, AL AF Medley, S. S. Donne, A. J. H. Kaita, R. Kislyakov, A. I. Petrov, M. P. Roquemore, A. L. TI Invited review article: Contemporary instrumentation and application of charge exchange neutral particle diagnostics in magnetic fusion energy experiments SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Review ID TIME-OF-FLIGHT; SPHERICAL TORUS EXPERIMENT; POLOIDAL DIVERTOR EXPERIMENT; LARGE HELICAL DEVICE; PRINCETON LARGE TORUS; ALCATOR C-MOD; TEST-REACTOR; ION TEMPERATURE; PLASMA DIAGNOSTICS; MICROCHANNEL PLATE AB An overview of the developments postcirca 1980s in the instrumentation and application of charge exchange neutral particle diagnostics on magnetic fusion energy experiments is presented. First, spectrometers that employ only electric fields and hence provide ion energy resolution but not mass resolution are discussed. Next, spectrometers that use various geometrical combinations of both electric and magnetic fields to provide both energy and mass resolutions are reviewed. Finally, neutral particle diagnostics based on utilization of time-of-flight techniques are presented. (C) 2008 American Institute of Physics. C1 [Medley, S. S.; Kaita, R.; Roquemore, A. L.] Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. [Donne, A. J. H.] EURATOM, FOM, Inst Plasma Phys Rijnhuizen, NL-3430 BE Nieuwegein, Netherlands. [Kislyakov, A. I.; Petrov, M. P.] AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. RP Medley, SS (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM medley@pppl.gov NR 103 TC 18 Z9 18 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2008 VL 79 IS 1 AR 011101 DI 10.1063/1.2823259 PG 16 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 257TQ UT WOS:000252821800001 PM 18248015 ER PT J AU Park, BK Sushkov, AO Budker, D AF Park, B. K. Sushkov, A. O. Budker, D. TI Precision polarimetry with real-time mitigation of optical-window birefringence SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ULTRATHIN FERROMAGNETIC-FILMS AB Optical-window birefringence is frequently a major obstacle in experiments measuring changes in the polarization state of light traversing a sample under investigation. It can contribute a signal indistinguishable from that due to the sample and complicate the analysis. Here, we explore a method to measure and compensate for the birefringence of an optical window using the reflection from the last optical surface before the sample. We demonstrate that this arrangement can cancel out false signals due to the optical-window birefringence-induced ellipticity drift to about 1%, for the values of total ellipticity less than 0.25 rad. (C) 2008 American Institute of Physics. C1 [Park, B. K.; Sushkov, A. O.; Budker, D.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. [Budker, D.] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Park, BK (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM novakyu@ocf.berkeley.edu; alexsushkov@berkeley.edu; budker@berkeley.edu RI Budker, Dmitry/F-7580-2016 OI Budker, Dmitry/0000-0002-7356-4814 NR 13 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2008 VL 79 IS 1 AR 013108 DI 10.1063/1.2835902 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 257TQ UT WOS:000252821800009 PM 18248023 ER PT J AU Swift, DC AF Swift, Damian C. TI X-ray diffraction from shock-loaded polycrystals SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID NATIONAL IGNITION FACILITY; COMPRESSION; DYNAMICS AB X-ray diffraction was demonstrated from shock-compressed polycrystalline metals on nanosecond time scales. Laser ablation was used to induce shock waves in polycrystalline foils of Be, 25-125 mu m thick. A second laser pulse was used to generate a plasma x-ray source by irradiation of a Ti foil. The x-ray source was collimated to produce a beam of controllable diameter, which was directed at the Be sample. X-rays were diffracted from the sample, and detected using films and x-ray streak cameras. The diffraction angle was observed to change with shock pressure. The diffraction angles were consistent with the uniaxial (elastic) and isotropic (plastic) compressions expected for the loading conditions used. Polycrystalline diffraction will be used to measure the response of the crystal lattice to high shock pressures and through phase changes. (c) 2008 American Institute of Physics. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Swift, DC (reprint author), Los Alamos Natl Lab, MS E526, Los Alamos, NM 87545 USA. EM damian.swift@physics.org NR 24 TC 3 Z9 4 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JAN PY 2008 VL 79 IS 1 AR 013906 DI 10.1063/1.2833824 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 257TQ UT WOS:000252821800035 PM 18248049 ER PT S AU Courant, ED AF Courant, E. D. BE Chao, AW Chou, W TI Early Milestones in the Evolution of Accelerators SO REVIEWS OF ACCELERATOR SCIENCE AND TECHNOLOGY, VOL 1 SE Reviews of Accelerator Science and Technology LA English DT Article; Book Chapter DE Accelerator; cyclotron; betatron; phase stability; synchrotron; strong focusing ID MAGNETIC INDUCTION; SYNCHROTRON; ELECTRONS AB About 80 years ago Rutherford [1] expressed the hope that particles could be accelerated to energies exceeding those occurring in radioactivity, enabling the study of nuclei and their constituents. Physicists and engineers have more than met this challenge, and today the LHC (Large Hadron Collider) at CERN, Geneva is about to accelerate protons to 7 trillion (7 x 10(12)) eV. Here we describe some of the crucial steps that have gotten us there. C1 [Courant, E. D.] Brookhaven Natl Lab, Upton, NY 11973 USA. RP Courant, ED (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. EM ecourant@msn.com NR 24 TC 1 Z9 1 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE SN 1793-6268 BN 978-981-283-521-5; 978-981-283-520-8 J9 REV ACCEL SCI TECH PY 2008 VL 1 BP 1 EP 5 DI 10.1142/S1793626808000022 D2 10.1142/7037 PG 5 WC History & Philosophy Of Science; Physics, Applied; Physics, Particles & Fields SC History & Philosophy of Science; Physics GA BE2SM UT WOS:000369972800002 ER PT S AU Chao, AW Chou, WR AF Chao, Alexander W. Chou, Weiren BE Chao, AW Chou, W TI Reviews of Accelerator Science and Technology Volume 1 Editorial Preface SO REVIEWS OF ACCELERATOR SCIENCE AND TECHNOLOGY, VOL 1 SE Reviews of Accelerator Science and Technology LA English DT Editorial Material; Book Chapter C1 [Chao, Alexander W.] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. [Chou, Weiren] Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Chao, AW (reprint author), Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. EM achao@slac.stanford.edu; chou@fnal.gov NR 0 TC 6 Z9 6 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE SN 1793-6268 BN 978-981-283-521-5; 978-981-283-520-8 J9 REV ACCEL SCI TECH PY 2008 VL 1 BP V EP VI D2 10.1142/7037 PG 2 WC History & Philosophy Of Science; Physics, Applied; Physics, Particles & Fields SC History & Philosophy of Science; Physics GA BE2SM UT WOS:000369972800001 ER PT S AU Wilson, PB AF Wilson, Perry B. BE Chao, AW Chou, W TI Electron Linacs for High Energy Physics SO REVIEWS OF ACCELERATOR SCIENCE AND TECHNOLOGY, VOL 1 SE Reviews of Accelerator Science and Technology LA English DT Article; Book Chapter DE Linear electron accelerators; accelerating structures; beam loading; rf breakdown; wake-fields; beam breakup; linear colliders AB The purpose of this article is to introduce some of the basic physical principles underlying the operation of electron linear accelerators (electron linacs). Electron linacs have applications ranging from linacs with an energy of a few MeV, such that the electrons are approximately relativistic, to future electron -positron linear colliders having a collision energy in the several-TeV energy range. For the most part, only the main accelerating linac is treated in this article. C1 [Wilson, Perry B.] Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. RP Wilson, PB (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. EM pwilson@slac.stanford.edu NR 44 TC 5 Z9 5 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE SN 1793-6268 BN 978-981-283-521-5; 978-981-283-520-8 J9 REV ACCEL SCI TECH PY 2008 VL 1 BP 7 EP 41 DI 10.1142/S1793626808000034 D2 10.1142/7037 PG 35 WC History & Philosophy Of Science; Physics, Applied; Physics, Particles & Fields SC History & Philosophy of Science; Physics GA BE2SM UT WOS:000369972800003 ER PT S AU Tollestrup, A Todesco, E AF Tollestrup, Alvin Todesco, Ezio BE Chao, AW Chou, W TI The Development of Superconducting Magnets for Use in Particle Accelerators: From the Tevatron to the LHC SO REVIEWS OF ACCELERATOR SCIENCE AND TECHNOLOGY, VOL 1 SE Reviews of Accelerator Science and Technology LA English DT Article; Book Chapter DE LHC; Tevatron; superconducting magnets; hadron colliders ID LARGE HADRON COLLIDER; NB3SN DIPOLE MAGNET; FIELD QUALITY; MAIN DIPOLES; DOUBLER MAGNETS; ENERGY DOUBLER; DESIGN; COILS; FABRICATION; SYSTEM AB Superconducting magnets have played key role in advancing the energy reach of proton synchrotrons and enabling them to play a major role in defining the Standard Model. The problems encountered and solved at the Tevatron are described and used as an introduction to the many challenges posed by the use of this technology. The LHC is being prepared to answer the many questions beyond the Standard Model and in itself is at the cutting edge of technology. A description of its magnets and their properties is given to illustrate the advances that have been made in the use of superconducting magnets over the past 30 years. C1 [Tollestrup, Alvin] Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. [Todesco, Ezio] CERN, Accelerator Technol Dept, CH-1211 Geneva, Switzerland. RP Tollestrup, A (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM alvin@fnal.gov; ezio.todesco@cern.ch NR 83 TC 7 Z9 7 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE SN 1793-6268 BN 978-981-283-521-5; 978-981-283-520-8 J9 REV ACCEL SCI TECH PY 2008 VL 1 BP 185 EP 210 DI 10.1142/S1793626808000101 D2 10.1142/7037 PG 26 WC History & Philosophy Of Science; Physics, Applied; Physics, Particles & Fields SC History & Philosophy of Science; Physics GA BE2SM UT WOS:000369972800010 ER PT S AU Sessler, A Malamud, E AF Sessler, Andrew Malamud, Ernest BE Chao, AW Chou, W TI Accelerators and the Accelerator Community SO REVIEWS OF ACCELERATOR SCIENCE AND TECHNOLOGY, VOL 1 SE Reviews of Accelerator Science and Technology LA English DT Article; Book Chapter DE Accelerator; accelerator community; accelerator history; accelerator applications AB In this paper,standing back looking from afar and adopting a historical perspective, the field of accelerator science is examined. The subjects explored are: how it grew, what were the forces that made it what it is, where it is now, and what it is likely to be in the future. Clearly, many personal opinions, are offered in this process. C1 [Sessler, Andrew] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Malamud, Ernest] Univ Nevada, Reno, NV 89557 USA. RP Sessler, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM AMSessler@lbl.gov; ernestmalamud@comcast.net NR 0 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA PO BOX 128 FARRER RD, SINGAPORE 9128, SINGAPORE SN 1793-6268 BN 978-981-283-521-5; 978-981-283-520-8 J9 REV ACCEL SCI TECH PY 2008 VL 1 BP 303 EP 317 DI 10.1142/S1793626808000125 D2 10.1142/7037 PG 15 WC History & Philosophy Of Science; Physics, Applied; Physics, Particles & Fields SC History & Philosophy of Science; Physics GA BE2SM UT WOS:000369972800014 ER PT J AU Zwolak, M Di Ventra, M AF Zwolak, Michael Di Ventra, Massimiliano TI Colloquium: Physical approaches to DNA sequencing and detection SO REVIEWS OF MODERN PHYSICS LA English DT Review ID SOLID-STATE NANOPORE; SINGLE-STRANDED-DNA; SCANNING-TUNNELING-MICROSCOPY; TRANSVERSE ELECTRONIC TRANSPORT; NANOMETER-SCALE PORE; POLYMER TRANSLOCATION; ION-CHANNEL; HAIRPIN MOLECULES; POLYNUCLEOTIDE MOLECULES; POLYCYTIDYLIC ACID AB With the continued improvement of sequencing technologies, the prospect of genome-based medicine is now at the forefront of scientific research. To realize this potential, however, a revolutionary sequencing method is needed for the cost-effective and rapid interrogation of individual genomes. This capability is likely to be provided by a physical approach to probing DNA at the single-nucleotide level. This is in sharp contrast to current techniques and instruments that probe (through chemical elongation, electrophoresis, and optical detection) length differences and terminating bases of strands of DNA. Several physical approaches to DNA detection have the potential to deliver fast and low-cost sequencing. Central to these approaches is the concept of nanochannels or nanopores, which allow for the spatial confinement of DNA molecules. In addition to their possible impact in medicine and biology, the methods offer ideal test beds to study open scientific issues and challenges in the relatively unexplored area at the interface between solids, liquids, and biomolecules at the nanometer length scale. This Colloquium emphasizes the physics behind these methods and ideas, critically describes their advantages and drawbacks, and discusses future research opportunities in the field. C1 [Zwolak, Michael] CALTECH, Dept Phys, Pasadena, CA 91125 USA. [Zwolak, Michael] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. [Di Ventra, Massimiliano] Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Zwolak, M (reprint author), CALTECH, Dept Phys, Pasadena, CA 91125 USA. EM mpz@lanl.gov; diventra@physics.ucsd.edu RI Di Ventra, Massimiliano/E-1667-2011; Zwolak, Michael/G-2932-2013 OI Di Ventra, Massimiliano/0000-0001-9416-189X; Zwolak, Michael/0000-0001-6443-7816 NR 134 TC 279 Z9 279 U1 9 U2 85 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0034-6861 EI 1539-0756 J9 REV MOD PHYS JI Rev. Mod. Phys. PD JAN-MAR PY 2008 VL 80 IS 1 BP 141 EP 165 DI 10.1103/RevModPhys.80.141 PG 25 WC Physics, Multidisciplinary SC Physics GA 247YS UT WOS:000252119100005 ER PT S AU Piscitelli, V Gonzalez, J Mao, XL Fernandez, A Russo, R AF Piscitelli, Vincent Gonzalez, Jhanis Mao, Xianglei Fernandez, Alberto Russo, Richard BE Wetter, NU Frejlich, J TI Micro-crater laser induced breakdown spectroscopy - an analytical approach in metals samples SO RIAO/OPTILAS 2007 SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th Ibero-American Meeting on Optics/9th Latin-American Meeting on Optics, Lasers, and Applications (RIAO/OPTILAS) CY OCT 21-26, 2007 CL Campinas, BRAZIL SP State Sao Paulo Res Fdn, State Univ Campinas, Phys Inst Gleb Wataghin, Brazilian Soc Phys, Natl Council Sci & Technol Dev, Opt Soc Amer, Int Soc Opt Engn, Int Commiss Opt, Abdus Salam Int Ctr Theoret Phys, European Opt Soc, Univ Campinas Res Fdn, Natl Council High Level Educ DE laser ablation; laser induced breakdown spectroscopy; micro- craters ID QUANTITATIVE-ANALYSIS; ABLATION AB The laser ablation has been increasing its popularity like as technique of chemical analysis. This is due to its great potentiality in the analysis of solid samples. On the way to contributing to the development of the technique, we in this work studied the laser induced breakdown spectroscopy (LIBS) in conditions of micro ablation for future studies of coverings and micro crates analysis. Craters between 2 and 7 micrometers of diameter were made using an Nd-YAG nanosecond laser in their fundamental emission of 1064 nm. In order to create these craters we use an objective lens of long distance work and 0.45 of numerical aperture. The atomic emission versus the energy of the laser and its effect on the size of craters was study. We found that below 3 micrometers although there was evidence of material removal by the formation of a crater, it was no detectable atomic emission for our instruments. In order to try to understand this, curves of size of crater versus plasma temperature using the Boltzmann distribution graphs taking the Copper emission lines in the visible region were made. In addition calibration curves for Copper and aluminum were made in two different matrices; one of it was a Cu/Zn alloy and the other a Zinc Matrix. The atomic lines Cu I (521.78 nm) and Al I (396.15 nm) was used. From the Calibration curve the analytical limit of detection and other analytical parameters were obtained. C1 [Piscitelli, Vincent; Fernandez, Alberto] UCV, Lab Espectroscopia Laser, Caracas, Venezuela. [Piscitelli, Vincent; Gonzalez, Jhanis; Mao, Xianglei; Russo, Richard] Lawrence Berkeley Natl lab, Berkeley, CA USA. RP Piscitelli, V (reprint author), UCV, Lab Espectroscopia Laser, Caracas, Venezuela. NR 11 TC 3 Z9 3 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0511-0 J9 AIP CONF PROC PY 2008 VL 992 BP 1166 EP + PG 2 WC Optics; Physics, Applied SC Optics; Physics GA BHR90 UT WOS:000255857900205 ER PT J AU Aschieri, P Ferrara, S Zumino, B AF Aschieri, P. Ferrara, S. Zumino, B. TI Duality rotations in nonlinear electrodynamics and in extended supergravity SO RIVISTA DEL NUOVO CIMENTO LA English DT Review ID UNILATERAL MATRIX EQUATIONS; NONCOMMUTATIVE GAUGE-THEORY; SPECIAL KAHLER GEOMETRY; EXTREMAL BLACK-HOLES; N=2 SUPERGRAVITY; YANG-MILLS; STRING THEORY; SELF-DUALITY; U-DUALITY; PHENOMENOLOGICAL LAGRANGIANS AB We review the general theory of duality rotations which, in four dimensions, exchange electric with magnetic fields. Necessary and sufficient conditions in order for a theory to have duality symmetry are established. A nontrivial example is Born-Infeld theory with n Abelian gauge fields and with Sp(2n,R) self-duality. We then review duality symmetry in supergravity theories. In the case of N = 2 supergravity duality rotations are in general not a symmetry of the theory Nit a key ingredient in order to formulate the theory itself. This is chic to the beautiful relation between the geometry of special Kahler manifolds and duality rotations. C1 [Aschieri, P.] Ctr Studi & Ric Enrico Fermi Compendio Viminale, I-00184 Rome, Italy. [Aschieri, P.] Univ Piemonte Orientale, Dipartimento Sci & Tecnol Avanzate, I-15100 Alessandria, Italy. [Aschieri, P.] Ist Nazl Fis Nucl, Sez Torino, Grp Coll Alessandria, I-15100 Alessandria, Italy. [Ferrara, S.] CERN, Theory Unit, Dept Phys, CH-1211 Geneva 23, Switzerland. [Ferrara, S.] Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. [Ferrara, S.] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA USA. [Zumino, B.] Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. [Zumino, B.] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Aschieri, P (reprint author), Ctr Studi & Ric Enrico Fermi Compendio Viminale, I-00184 Rome, Italy. EM aschieri@to.infn.it; sergio.ferrara@cern.ch; bzumino@lbl.gov RI Aschieri, Paolo/J-2965-2012; OI Ferrara, Sergio/0000-0001-7662-3480 NR 122 TC 40 Z9 40 U1 0 U2 1 PU SOC ITALIANA FISICA PI BOLOGNA PA VIA SARAGOZZA, 12, I-40123 BOLOGNA, ITALY SN 0393-697X J9 RIV NUOVO CIMENTO JI Riv. Nuovo Cimento PY 2008 VL 31 IS 11 BP 625 EP 707 DI 10.1393/ncr/i2008-10038-8 PG 83 WC Physics, Multidisciplinary SC Physics GA 407AR UT WOS:000263336500001 ER PT J AU Pieper, SC AF Pieper, Steven C. TI Quantum Monte Carlo calculations of light nuclei SO RIVISTA DEL NUOVO CIMENTO LA English DT Article ID SCATTERING DATA; ENERGIES AB During the last 15 years, there has been much progress in defining the nuclear Hamiltonian and applying quantum Monte Carlo methods to the calculation of light nuclei. I describe both aspects of this work and some recent results. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Pieper, SC (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. FU US Department of Energy, Office of Nuclear Physics [DE-AC02-06CH11357] FX As can be seen front the author lists of the citations, the work reported in this contribution is the result of long-term collaborations with J. CARLSON (who invented nuclear CFMC), K. M. NOLLETT (who is doing the GFMC scattering), V. R. PANDHARIPANDE (who for many years guided and inspired our group), R. SCHIAVILLA (who has provided the expertise on the electroweak currents) and R. B. WIRINGA (who has developed the VMC wave functions). I thank R. B. WIRINGA for also making a, critical reading of this MS. The work would not have been possible without extensive computer resources provided over the years by Argonne's Mathematics and Computer Science Division (most recently on the IBM Blue Gene), Argonne's Laboratory Computing Resource Center; and the US Department of Energy's National Energy Research Scientific Computing Center. This work is supported by the US Department of Energy, Office of Nuclear Physics. under contract DE-AC02-06CH11357. NR 43 TC 47 Z9 47 U1 0 U2 3 PU SOC ITALIANA FISICA PI BOLOGNA PA VIA SARAGOZZA, 12, I-40123 BOLOGNA, ITALY SN 0393-697X EI 1826-9850 J9 RIV NUOVO CIMENTO JI Riv. Nuovo Cimento PY 2008 VL 31 IS 12 BP 709 EP 740 DI 10.1393/ncr/i2009-10039-1 PG 32 WC Physics, Multidisciplinary SC Physics GA 406QS UT WOS:000263310600001 ER PT J AU Divan, R Ma, Q Mancini, DC Keane, DT AF Divan, R. Ma, Q. Mancini, D. C. Keane, D. T. TI Controlled X-Ray Induced Gold Nanoparticles Deposition SO ROMANIAN JOURNAL OF INFORMATION SCIENCE AND TECHNOLOGY LA English DT Article AB This paper outlines new approaches for utilizing X-rays for gold nanoparticles deposition by performing Surface Photochemistry Induced by X-ray Irradiation (SPIXI). High-energy synchrotron radiation was used to induce the deposition of gold nanoparticles from a gold-salt solution onto different surf aces. By controlling the deposition parameters (dose, solution, surfactants, and stabilizer polymer concentrations), the distribution and average size of the nanoparticles can be influenced. The distribution of the deposited particle heights and diameters at low doses suggests there is a mechanism of growth of the particles after nucleation on the surface. C1 [Divan, R.; Mancini, D. C.] Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA. [Ma, Q.; Keane, D. T.] Northwestern Univ, Synchrotron Res Ctr, DND CAT, Argonne, IL 60439 USA. RP Divan, R (reprint author), Argonne Natl Lab, Ctr Nanoscale Mat, 9700 S Cass Ave, Argonne, IL 60439 USA. EM divan@aps.anl.gov NR 23 TC 2 Z9 2 U1 0 U2 3 PU EDITURA ACAD ROMANE PI BUCURESTI PA CALEA 13 SEPTEMBRIE NR 13, SECTOR 5, BUCURESTI 050711, ROMANIA SN 1453-8245 J9 ROM J INF SCI TECH JI Rom. J. Inform. Sci. Technol. PY 2008 VL 11 IS 1 BP 71 EP 84 PG 14 WC Computer Science, Theory & Methods; Instruments & Instrumentation; Physics, Applied SC Computer Science; Instruments & Instrumentation; Physics GA V11MU UT WOS:000207536500007 ER PT J AU Atanasiu, CV Gunter, S Lackner, K Moraru, A Zakharov, LE Subbotin, AA AF Atanasiu, C. V. Guenter, S. Lackner, K. Moraru, A. Zakharov, L. E. Subbotin, A. A. TI The energy principle applied to diverted Tokamak configurations SO ROMANIAN REPORTS IN PHYSICS LA English DT Article DE MHD stablity; fusion; tokamak ID TEARING MODE-STABILITY; REGION MATCHING DATA; INSTABILITIES; PRESSURE; PLASMAS AB Writing the expression of the potential energy in terms of the perturbation of the flux function, and performing an Euler minimisation, one obtains a system of ordinary differential equations in that perturbation. For a diverted configuration, the usual vanishing boundary conditions for the perturbed flux function at the magnetic axis and at infinity can no longer be used. In place of the vanishing boundary conditions at infinity, an approach to fix "natural" boundary conditions for the system of differential equations for the perturbed flux function, just at the plasma boundary has been developed. C1 [Atanasiu, C. V.] MEdC EURATOM Assoc, Natl Inst Laser Plasma & Radiat Phys, Bucharest, Romania. [Guenter, S.; Lackner, K.] Max Planck Inst Plasma Phys, EURATOM Assoc, D-85748 Garching, Germany. [Moraru, A.] Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. [Zakharov, L. E.] Polytech Univ, R-77206 Bucharest, Romania. [Subbotin, A. A.] Russian Res Ctr, IV Kurchatov Inst, Moscow 12382, Russia. RP Atanasiu, CV (reprint author), MEdC EURATOM Assoc, Natl Inst Laser Plasma & Radiat Phys, POB MG-36, Bucharest, Romania. EM cva@ipp.mpg.de NR 29 TC 0 Z9 0 U1 0 U2 0 PU EDITURA ACAD ROMANE PI BUCURESTI PA CALEA 13 SEPTEMBRIE NR 13, SECTOR 5, BUCURESTI 050711, ROMANIA SN 1221-1451 J9 ROM REP PHYS JI Rom. Rep. Phys. PY 2008 VL 60 IS 3 BP 635 EP 646 PG 12 WC Physics, Multidisciplinary SC Physics GA 348XH UT WOS:000259242900023 ER PT B AU Chen, M Wang, XR Gunasekaran, R Qi, HR Shankar, M AF Chen, Ming Wang, Xiaorui Gunasekaran, Raghul Qi, Hairong Shankar, Mallikarjun GP IEEE Comp Soc TI Control-Based Real-Time Metadata Matching for Information Dissemination SO RTCSA 2008: 14TH IEEE INTERNATIONAL CONFERENCE ON EMBEDDED AND REAL-TIME COMPUTING SYSTEMS AND APPLICATIONS - PROCEEDINGS LA English DT Proceedings Paper CT 14th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications CY AUG 25-27, 2008 CL Kaohsiung, TAIWAN SP IEEE, Natl Taiwan Univ, Natl Cheng Kung Univ, Natl Sun Yat Sen Univ ID DATABASES AB Real-time information dissemination is of increasing importance to our society Existing work mainly focuses on delivering information from sources to sinks in a timely manner based on established subscriptions, with the assumption that those subscriptions are persistent. However the bottleneck of many real-time information dissemination systems is actually the matching process to continuously reevaluate such subscriptions between numerous sources and numerous sinks, in response to dynamically varying information attributes at runtime. In this paper we propose a feedback controller to adaptively meet the response time constraints on metadata matching in an example information dissemination system. Our controller features a rigorous design based on well-established feedback control theory for guaranteed control accuracy and system stability. Empirical results on a physical test-bed demonstrate that our controller outperforms both an open-loop solution and a typical heuristic solution, by having more accurate control and better system quality of service. C1 [Chen, Ming; Wang, Xiaorui; Gunasekaran, Raghul; Qi, Hairong] Univ Tennessee, Dept Elect Engn & Comp Sci, Knoxville, TN 37996 USA. [Shankar, Mallikarjun] Oak Ridge Natl Lab, Dept Comp Sci & Engn, Oak Ridge, TN 37830 USA. RP Chen, M (reprint author), Univ Tennessee, Dept Elect Engn & Comp Sci, Knoxville, TN 37996 USA. EM mchen11@utk.edu; xwang@utk.edu; raghul@utk.edu; hqi@utk.edu; shankarm@ornl.gov RI Wang, Xiaorui/L-2774-2016; OI Wang, Xiaorui/0000-0001-9633-1418; Shankar, Mallikarjun/0000-0001-5289-7460 FU subcontract from the Department of Homeland Security-sponsored Southeast Region Research Initiative (SERRI) at the National Nuclear Security Administration's Y-12 National Security Complex; Laboratory Directed Research and Development Program of Oak Ridge National Laboratory [DE-AC05-00OR22725] FX This research is supported in part by a subcontract from the Department of Homeland Security-sponsored Southeast Region Research Initiative (SERRI) at the National Nuclear Security Administration's Y-12 National Security Complex , and by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory under Contract No. DE-AC05-00OR22725. We would also like to thank Dieter Gawlick at Oracle Corporation for his help with the INFOD system NR 27 TC 1 Z9 1 U1 0 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3349-0 PY 2008 BP 133 EP + DI 10.1109/RTCSA.2008.24 PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIK53 UT WOS:000260407600014 ER PT S AU Nugent, P Thomas, R Aldering, G AF Nugent, Peter Thomas, Rollin Aldering, Greg BE Stevens, RL TI Optimizing Type Ia supernova follow-up in future dark energy surveys - art. no. 012011 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID SPECTRA AB In the next-generation supernova surveys (Palomar Transient Factory, Dark Energy Survey, LSST, JDEM, etc.) maximizing the cosmological return on each supernova and limiting the systematic uncertainties will be crucial for determining the nature of dark energy. Here we present recent results from the Nearby Supernova Factory, a program that has followed almost 200 SN Ia in the Hubble flow with spectrophotometry. We have used the code SYNAPPS, a combination of the SYNOW spectrum synthesis fitter and the APPSPACK optimization code to automatically perform a highly parameterized fit to observational spectra, to begin the work of identifying the spectral features in a SN Ia that are most important for using these explosions as cosmological probes. C1 [Nugent, Peter; Thomas, Rollin; Aldering, Greg] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Nugent, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12011 EP 12011 DI 10.1088/1742-6596/125/1/012011 PG 7 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700012 ER PT S AU Shepard, R AF Shepard, R. BE Stevens, RL TI Advanced software for the calculation of thermochemistry, kinetics, and dynamics - art. no. 012016 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID NONLINEAR-WAVE FUNCTIONS AB The Born-Oppenheimer separation of the Schrodinger equation allows the electronic and nuclear motions to be solved in three steps: (1) the solution of the electronic wave function at a discrete set of molecular conformations; (2) the fitting of this discrete set of energy values in order to construct an analytical approximation to the potential energy surface (PES) at all molecular conformations; and (3) the use of this analytical PES to solve for the nuclear motion by using either time-dependent or time-independent formulations to compute molecular energy values, chemical reaction rates, and cumulative reaction probabilities. This project involves the development of technology to address all three of these steps. This report focuses on our recent work with nonlinear parameterization of the electronic wave functions. C1 Argonne Natl Lab, Chem Sci & Engn Div, Argonne, IL 60439 USA. RP Shepard, R (reprint author), Argonne Natl Lab, Chem Sci & Engn Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12016 EP 12016 DI 10.1088/1742-6596/125/1/012016 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700017 ER PT S AU Franklin, M Kotamarthi, VR Stein, ML Cook, DR AF Franklin, Meredith Kotamarthi, V. Rao Stein, Michael L. Cook, David R. BE Stevens, RL TI Generating data ensembles over a model grid from sparse climate point measurements - art. no. 012019 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID STATIONARY COVARIANCE FUNCTIONS AB Parameterizations in high-end climate models can be evaluated with observed climate and meteorological data. Often this evaluation is achieved by averaging measured quantities over time and space to match the spatial and temporal resolution of a gridded climate model without any regard for the statistical errors in doing so. We present a statistical method to interpolate sparsely located surface measurements into a uniform spatial grid representative of global and regional models of the atmosphere and climate. This method provides estmiates of mean values over the entire domain containing the measurement sites as well as the uncertainty in the estimated quantities at the grid locations through multiple simulations to create "data ensembles." We demonstrate this method using measurements of surface sensible heat flux over the southern Great Plains region gathered through the Department of Energy's Atmospheric Radiation Measurement (ARM) program. Application to the numerous other climate variables measured through the ARM program and the development of a software tool to streamline data management and implementation of the statistical models is also discussed. C1 [Franklin, Meredith; Kotamarthi, V. Rao; Cook, David R.] Argonne Natl Lab, Argonne, IL 60439 USA. RP Franklin, M (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Kotamarthi, Veerabhadra Rao/0000-0002-2612-7590 NR 9 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12019 EP 12019 DI 10.1088/1742-6596/125/1/012019 PG 7 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700020 ER PT S AU McGraw, R Leng, L Zhu, W Riemer, N West, M AF McGraw, Robert Leng, Ling Zhu, Wei Riemer, Nicole West, Matthew BE Stevens, RL TI Aerosol dynamics using the quadrature method of moments: Comparing several quadrature schemes with particle-resolved simulation - art. no. 012020 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID POPULATIONS; COAGULATION AB The method of moments (MOM) is a statistically based alternative to sectional and modal methods for aerosol simulation. The MOM is highly efficient as the aerosol distribution is represented by its lower-order moments and only these, not the full distribution itself, are tracked during simulation. Quadrature is introduced to close the moment equations under very general growth laws and to compute aerosol physical and optical properties directly from moments. In this paper the quadrature method of moments (QMOM) is used in a bivariate test tracking of aerosol mixing state. Two aerosol populations, one enriched in soot and the other in sulfate, are allowed to interact through coagulation to form a generally-mixed third particle population. Quadratures of varying complexity (including two candidate schemes for use in climate models) are described and compared with benchmark results obtained by using particle-resolved simulation. Low-order quadratures are found to be highly accurate, and Gauss and Gauss-Radau quadratures appear to give nested lower and upper bounds, respectively, to aerosol mixing rate. These results suggest that the QMOM makes it feasible to represent the generallymixed states of aerosols and track their evolution in climate models. C1 [McGraw, Robert] Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. RP McGraw, R (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. OI West, Matthew/0000-0002-7605-0050 NR 9 TC 2 Z9 2 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12020 EP 12020 DI 10.1088/1742-6596/125/1/012020 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700021 ER PT S AU Taylor, MA Edwalrds, J Cyr, AS AF Taylor, M. A. Edwalrds, J. Cyr, A. St. BE Stevens, RL TI Petascale atmospheric models for the Community Climate System Model: new developments and evaluation of scalable dynamical cores - art. no. 012023 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID SHALLOW-WATER MODEL; GENERAL-CIRCULATION; PARAMETERIZATIONS AB We present results from the integration and evaluation of the spectral finite-element method into the atmospheric component of the Community Climate System Model (CCSM). This method overcomes the atmospheric scalability bottleneck by allowing the use of a true two-dimensional domain decomposition for the first time in the CCSM. Scalability is demonstrated out to 86,200 processors with an average grid spacing of 0.25 degrees (25 km). We present initial evaluations results using a standardized test problem with the full suite of CCSM atmospheric model forcings and subgrid parametrizations but without the CCSM land, ice, or ocean models. For this realistic setting, the true solution is unknown. Even convergence under mesh refinement is not expected, so we cannot rely on high-resolution reference solutions. Instead we focus on intermodel comparisons and use the Williamson equivalent resolution methodology to evaluate the results. C1 [Taylor, M. A.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Taylor, MA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 23 TC 22 Z9 22 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12023 EP 12023 DI 10.1088/1742-6596/125/1/012023 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700024 ER PT S AU Bell, JB Cheng, RK Day, MS Beckner, VE Lijewski, MJ AF Bell, J. B. Cheng, R. K. Day, M. S. Beckner, V. E. Lijewski, M. J. BE Stevens, RL TI Interaction of turblence and chemistry in a low-swirl burner - art. no. 012027 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID FLAMES AB New combustion systems based on ultra-lean premixed combustion have the potential for dramatically reducing pollutant emissions in transportation systems, heat, and stationary power generation. However, lean premixed flames are highly susceptible to fluid-dynamical combustion instabilities, making robust and reliable systems difficult to design. Low-swirl burners are emerging as an important technology for meeting design requirements in terms of both reliability and emissions for next-generation combustion devices. In this paper, we present simlations of a laboratory-scale low-swirl burner using detailed chemistry and transport without incorporating explicit models for turbulence or turbulence/chemistry interaction. We consider two fuels, methane and hydrogen, each at two turbulent intensities. Here we examine some of the basic properties of the flow field and the flame structure. We focus on the differences in flame behavior for the two fuels, particularly on the hydrogen flame, which burns with a cellular structures. C1 [Bell, J. B.; Day, M. S.; Beckner, V. E.; Lijewski, M. J.] Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Computat Sci & Engn, Berkeley, CA 94720 USA. RP Bell, JB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Computat Sci & Engn, Berkeley, CA 94720 USA. NR 13 TC 6 Z9 6 U1 3 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12027 EP 12027 DI 10.1088/1742-6596/125/1/012027 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700028 ER PT S AU Chen, JH Yoo, CS Sankaran, R Oefelein, JC AF Chen, J. H. Yoo, C. S. Sankaran, R. Oefelein, J. C. BE Stevens, RL TI High-fidelity simulations for clean and efficient combustion of alternative fuels - art. no. 012028 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The monolithic nature of transportation technologies offers opportunities for significant improvements in efficiency of 25-50% through strategic technical investments in both advanced fuels and new low-temperature engine concepts. The application of direct numerical simulation (DNS) provides a way to study fundamental issues related to small-scale combustion processes in well-defined canonical configurations, whereas the application of large eddy simulation (LES) provides a formal treatment of the full range of time and length scales that exist in turbulent reacting flows, and thus provides a direct link to experimental studies of relevant combustion devices. In the present study, through DOE INCITE and Oak Ridge National Laboratory 250 Tflop Transition-to-Operations grants in 2008, DNS is performed to understand how a lifted autoignitive flame is stabilized, and LES is performed to understand the high-pressure injection and mixing processes in internal combustion engines. Understanding of these and other fundamental issues is needed to develop robust and reliable ignition and combustion models for the combustion regimes observed under low-temperature combustion engine environments using alternative fuels. C1 [Chen, J. H.; Yoo, C. S.; Sankaran, R.; Oefelein, J. C.] Sandia Natl Labs, Reacting Flows Res Dept, Livermore, CA 94550 USA. RP Chen, JH (reprint author), Sandia Natl Labs, Reacting Flows Res Dept, Livermore, CA 94550 USA. RI Yoo, Chun Sang/E-5900-2010; Sankaran, Ramanan/D-9254-2015 OI Yoo, Chun Sang/0000-0003-1094-4016; Sankaran, Ramanan/0000-0002-5352-9915 NR 5 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12028 EP 12028 DI 10.1088/1742-6596/125/1/012028 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700029 ER PT S AU Lignell, DO Chen, JH Richardson, ES AF Lignell, D. O. Chen, J. H. Richardson, E. S. BE Stevens, RL TI Terascale direct numerical simulations of turbulent combustion - fundamental understanding towards predictive models - art. no. 012031 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID JET FLAMES; EXTINCTION AB Advances in high-performance computational capabilities enable scientific simulations with increasingly realistic physical representations. This situation is especially true of turbulent combustion involving multiscale interactions between turbulent flow, complex chemical reaction, and scalar transport. A fundamental understanding of combustion processes is crucial to the development and optimization of next-generation combustion technologies operating with alternative fuels, at higher pressures, and under less stable operating conditions, such as highly dilute, stratified mixtures. Direct numerical simulations (DNS) of turbulent combustion resolving all flow and chemical features in canonical configurations are used to improve fundamental understanding of complex flow processes and to provide a database for the development and validation of combustion models. A description of the DNS solver and its optimization for use in massively parallel simulations is presented. Recent DNS results from a series of three combustion configurations are presented: soot formation and transport in a nonpremixed ethylene jet flame, the effect of fuel stratification in methane Bunsen flames, and extinction and reignition processes in nonpremixed ethylene jet flames. C1 [Lignell, D. O.; Chen, J. H.; Richardson, E. S.] Sandia Natl Labs, Reacting Flows Res Dept, Livermore, CA 94550 USA. RP Lignell, DO (reprint author), Sandia Natl Labs, Reacting Flows Res Dept, Livermore, CA 94550 USA. NR 22 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12031 EP 12031 DI 10.1088/1742-6596/125/1/012031 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700032 ER PT S AU Barrett, RR Alam, SR de Almeida, VF Bernholdt, DE Elwasif, WR Kuehn, JA Poole, SW Shet, AG AF Barrett, Richard R. Alam, Sadaf R. de Almeida, Valmor F. Bernholdt, David E. Elwasif, Wael R. Kuehn, Jeffery A. Poole, Stephen W. Shet, Aniruddha G. BE Stevens, RL TI Exploring HPCS Languages in Scientific Computing - art. no. 012034 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID PERFORMANCE COMPUTATIONAL CHEMISTRY AB As computers scale up dramatically to tens and hundreds of thousands of cores, develop deeper computational and memory hierarchies, and increased heterogeneity, developers of scientific software are increasingly challenged to express complex parallel simulations effectively and efficiently. In this paper, we explore the three languages developed under the DARPA High-Productivity Computing Systems (HPCS) program to help address these concerns: Chapel, Fortress, and X10. These languages provide a variety of features not found in currently popular HPC programming environments and make it easier to express powerful computational constructs, leading to new ways of thinking about parallel programming. Though the languages and their implementations are not yet mature enough for a comprehensive evaluation, we discuss some of the important features, and provide examples of how they can be used in scientific computing. We believe that these characteristics will be important to the future of high-performance scientific computing, whether the ultimate language of choice is one of the HPCS languages or something else. C1 [Barrett, Richard R.; Alam, Sadaf R.; de Almeida, Valmor F.; Bernholdt, David E.; Elwasif, Wael R.; Kuehn, Jeffery A.; Poole, Stephen W.; Shet, Aniruddha G.] Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Barrett, RR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN USA. RI de Almeida, Valmor/P-5498-2016 OI de Almeida, Valmor/0000-0003-0899-695X NR 24 TC 0 Z9 0 U1 1 U2 16 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12034 EP 12034 DI 10.1088/1742-6596/125/1/012034 PG 13 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700035 ER PT S AU Heroux, MA AF Heroux, Michael A. BE Stevens, RL TI Design issues for numerical libraries on scalable multicore architectures - art. no. 012035 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Future generations of scalable computers will rely on multicore nodes for a significant portion of overall system performance. At present, most applications and libraries cannot exploit multiple cores beyond running addition MPI processes per node. In this paper we discuss important multicore architecture issues, programming models, algorithms requirements and software design related to effective use of scalable multicore computers. In particular, we focus on important issues for library research and development, making recommendations for how to effectively develop libraries for future scalable computer systems. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Heroux, MA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 1 Z9 1 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12035 EP 12035 DI 10.1088/1742-6596/125/1/012035 PG 11 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700036 ER PT S AU Chacon, L AF Chacon, L. BE Stevens, RL TI Scalable parallel implicit solvers for 3D magnetohydrodynamics - art. no. 012041 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID KRYLOV METHODS; ALGORITHM; EQUATIONS; SYSTEMS; GMRES AB The efficient integration of the extended magnetohydrodynamics (XMHD) model is critical for present and future modeling needs of fusion plasmas and is at the core of several interacting SciDAC centers. However, XMHD is a remarkably challenging system of PDEs, featuring a stiff multiscale character both in time and space. Such stiff character has hindered progress toward a truly scalable, efficient, and accurate nonlinear XMHD algorithm. In this paper, we discuss recent algorithmic developments that demonstrate that such an XMHD algorithm is within reach. The approach is based on fully implicit time integration and employs parallel Jacobian-free Newton-Krylov technology, preconditioned with multigrid methods for algorithmic scalability. The algorithm has been tested on a variety of 2D and 3D configurations that demonstrate its excellent algorithmic scalability properties, both serially and in parallel up to 4096 processors and 134 million unknowns. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chacon, L (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI Chacon, Luis/0000-0002-4566-8763 NR 21 TC 14 Z9 14 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12041 EP 12041 DI 10.1088/1742-6596/125/1/012041 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700042 ER PT S AU Tang, WM AF Tang, William M. BE Stevens, RL TI Scientific and computational challenges of the Fusion Simulation Project (FSP) - art. no. 012047 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB This paper highlights the scientific and computational challenges facing the Fusion Simulation Project (FSP). The primary objective is to develop advanced software designed to use leadership-class computers for carrying out multiscale physics simulations to provide information vital to delivering a realistic integrated fusion simulation model with unprecedented physics fidelity. This multiphysics capability will be unprecedented in that in the current FES applications domain, the largest-scale codes are used to carry out first-principles simulations of mostly individual phenomena in realistic 3D geometry while the integrated models are much smaller-scale, lower-dimensionality codes with significant empirical elements used for modeling and designing experiments. The FSP is expected to be the most up-to-date embodiment of the theoretical and experimental understanding of magnetically confined thermonuclear plasmas and to provide a living framework for the simulation of such plasmas as the associated physics understanding continues to advance over the next several decades. Substantive progress on answering the outstanding scientific questions in the field will drive the FSP toward its ultimate goal of developing a reliable ability to predict the behavior of plasma discharges in toroidal magnetic fusion devices on all relevant time and space scales. From a computational perspective, the fusion energy science application goal to produce high-fidelity, whole-device modeling capabilities will demand computing resources in the petascale range and beyond, together with the associated multicore algorithmic formulation needed to address burning plasma issues relevant to ITER - a multibillion dollar collaborative device involving seven international partners representing over half the world's population. Even more powerful exascale platforms will be needed to meet the future challenges of designing a demonstration fusion reactor (DEMO). Analogous to other major applied physics modeling projects (e.g., ASCI), the FSP will need to develop software in close collaboration with experimental researchers and validated against experimental data from tokamaks around the world. Specific examples of expected advances needed to enable a premier comprehensive integrated modeling capability are discussed. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. RP Tang, WM (reprint author), Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. NR 12 TC 7 Z9 7 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12047 EP 12047 DI 10.1088/1742-6596/125/1/012047 PG 15 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700048 ER PT S AU Edwards, RA AF Edwards, Robert A. BE Stevens, RL TI The smallest cells pose the biggest problems: high-performance computing and the analysis of metagenome sequence data - art. no. 012050 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID PROJECT AB New high-throughput DNA sequencing technologies have revolutionized how scientists study the organisms around us. In particular, microbiology - the study of the smallest, unseen organisms that pervade our lives - has embraced these new techniques to characterize and analyze the cellular constituents and use this information to develop novel tools, techniques, and therapeutics. So-called next-generation DNA sequencing platforms have resulted in huge increases in the amount of raw data that can be rapidly generated. Argonne National Laboratory developed the premier platform for the analysis of this new data (mg-rast) that is used by microbiologists worldwide. This paper uses the accounting from the computational analysis of more than 10,000,000,000 bp of DNA sequence data, describes an analysis of the advanced computational requirements, and suggests the level of analysis that will be essential as microbiologists move to understand how these tiny organisms affect our every day lives. The results from this analysis indicate that data analysis is a linear problem, but that most analyses are held up in queues. With sufficient resources, computations could be completed in a few hours for a typical dataset. These data also suggest execution times that delimit timely completion of computational analyses, and provide bounds for problematic processes. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Edwards, RA (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 8 TC 1 Z9 1 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12050 EP 12050 DI 10.1088/1742-6596/125/1/012050 PG 8 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700051 ER PT S AU Oehmen, CS Cannon, WR AF Oehmen, Christopher S. Cannon, William R. BE Stevens, RL TI Bringing high-performance computing to the biologist's workbench: approaches, applications, and challenges - art. no. 012052 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID PSI-BLAST; MANAGEMENT; SIMULATION; CLUSTERS; SYSTEMS AB Data-intensive and high-performance computing are poised to significantly impact the future of biological research which is increasingly driven by the prevalence of high-throughput experimental methodologies for genome sequencing, transcriptomics, proteomics, and other areas. Large centers such as NIH's National Center for Biotechnology Information, The Institute for Genomic Research, and the DOE's Joint Genome Institute) have made extensive use of multiprocessor architectures to deal with some of the challenges of processing, storing and curating exponentially growing genomic and proteomic datasets, thus enabling users to rapidly access a growing public data source, as well as use analysis tools transparently on high-performance computing resources. Applying this computational power to single-investigator analysis, however, often relies on users to provide their own computational resources, forcing them to endure the learning curve of porting, building, and running software on multiprocessor architectures. Solving the next generation of large-scale biology challenges using multiprocessor machines-from small clusters to emerging petascale machines-can most practically be realized if this learning curve can be minimized through a combination of workflow management, data management and resource allocation as well as intuitive interfaces and compatibility with existing common data formats. C1 [Oehmen, Christopher S.; Cannon, William R.] Pacific NW Natl Lab, Richland, WA 99354 USA. RP Oehmen, CS (reprint author), Pacific NW Natl Lab, Richland, WA 99354 USA. RI Cannon, William/K-8411-2014 OI Cannon, William/0000-0003-3789-7889 NR 28 TC 1 Z9 1 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12052 EP 12052 DI 10.1088/1742-6596/125/1/012052 PG 9 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700053 ER PT S AU Petridis, L Smith, JC AF Petridis, Loukas Smith, Jeremy C. BE Stevens, RL TI Cellulosic ethanol: progress towards a simulation model of lignocellulosic biomass - art. no. 012055 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID MECHANICS FORCE-FIELD; ENZYMATIC-HYDROLYSIS AB A CHARMM molecular mechanics force field for lignin is derived. Parameterization is based on reproducing quantum mechanical data of model compounds. Partial atomic charges are derived by the examination of methoxybenzene:water interactions. Dihedral parameters are optimized by fitting to critical rotational potentials, and bonded parameters are obtained by optimizing vibrational frequencies and normal modes. The force field is validated by performing a molecular dynamics simulation of a crystal of a lignin fragment molecule and comparing simulation-derived structural features with experimental results. Together with the existing force field for polysaccharides, this work will enable full simulations of lignocellulose. C1 [Petridis, Loukas; Smith, Jeremy C.] Oak Ridge Natl Lab, Ctr Biophys Mol, Oak Ridge, TN USA. RP Petridis, L (reprint author), Oak Ridge Natl Lab, Ctr Biophys Mol, Oak Ridge, TN USA. RI Petridis, Loukas/B-3457-2009; smith, jeremy/B-7287-2012 OI Petridis, Loukas/0000-0001-8569-060X; smith, jeremy/0000-0002-2978-3227 NR 21 TC 4 Z9 4 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12055 EP 12055 DI 10.1088/1742-6596/125/1/012055 PG 7 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700056 ER PT S AU Wang, LW AF Wang, Lin-Wang BE Stevens, RL TI Large-scale ab initio nanostructure electronic structure calculations for energy applications - art. no. 012059 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID SEEDED GROWTH AB Nanostructures have often been used to construct third-generation solar cells and for solid state lighting. To fully explore the potential for such energy applications, we need to understand the electronic and optical properties of the corresponding nanosystems. These include the quantum confinement effects, the electron hole separations, the exciton binding energy, and optical absorption spectrums. In the past ten years, we have developed a systematic approach to study such properties of thousand atom nanostructures based on ab initio calculations and large -cale comutations. In this paper, we present a few examples using such an approach to study the nanostructure properties related to energy applications. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. RP Wang, LW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. NR 10 TC 1 Z9 1 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12059 EP 12059 DI 10.1088/1742-6596/125/1/012059 PG 7 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700060 ER PT S AU Dean, DJ AF Dean, D. J. BE Stevens, RL TI Computational nuclear structure: Exploring nuclei through INCITE - art. no. 012062 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Computing provided by the INCITE program is essential to efforts to disentangle the nuclear puzzle. The goal of the computational nuclear structure INCITE project is to provide a comprehensive description of all nuclei and their reactions, by using a variety of computationally intensive techniques. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Dean, DJ (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. OI Dean, David/0000-0002-5688-703X NR 0 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12062 EP 12062 DI 10.1088/1742-6596/125/1/012062 PG 2 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700063 ER PT S AU Joo, B AF Joo, Balint CA USQCD Collaboration BE Stevens, RL TI Continuing progress on a lattice QCD software infrastructure - art. no. 012066 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB We report on the progress of the software effort in the QCD application area of SciDAC. In particular, we discuss how the software developed under SciDAC enabled the aggressive exploitation of leadership computers, and we report on progress in the area of QCD software for multi-core architectures. C1 [Joo, Balint] Thomas Jefferson Natl Lab, Newport News, VA 23606 USA. RP Joo, B (reprint author), Thomas Jefferson Natl Lab, Newport News, VA 23606 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12066 EP 12066 DI 10.1088/1742-6596/125/1/012066 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700067 ER PT S AU Kronfeld, AS AF Kronfeld, Andreas S. CA USQCD Collaboration BE Stevens, RL TI Quantum chromodynamics with advanced computing - art. no. 012067 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID LATTICE QCD; HIGGS MASS AB We survey results in lattice quantum chromodynamics from groups in the USQCD Collaboration. The main focus is on physics, but many aspects of the discussion are aimed at an audience of computational physicists. C1 [Kronfeld, Andreas S.] Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Kronfeld, AS (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 72 TC 2 Z9 2 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12067 EP 12067 DI 10.1088/1742-6596/125/1/012067 PG 17 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700068 ER PT S AU Fischer, P Lottes, J Pointer, D Siegel, A AF Fischer, Paul Lottes, James Pointer, David Siegel, Andrew BE Stevens, RL TI Petascale algorithms for reactor hydrodynamics - art. no. 012076 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB We describe recent algorithmic developments that have enabled large eddy simulations of reactor flows on up to P = 65, 000 processors on the IBM BG/P at the Argonne Leadership Computing Facility. C1 [Fischer, Paul; Lottes, James; Pointer, David; Siegel, Andrew] Argonne Natl Lab, Argonne, IL 60439 USA. RP Fischer, P (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Pointer, W. David/0000-0003-0946-7937 NR 7 TC 23 Z9 23 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12076 EP 12076 DI 10.1088/1742-6596/125/1/012076 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700077 ER PT S AU Lee, L Akcelik, V Ge, L Chen, S Schussman, G Candel, A Li, Z Xiao, L Kabel, A Uplenchwar, R Ng, C Ko, K AF Lee, L. Akcelik, V. Ge, L. Chen, S. Schussman, G. Candel, A. Li, Z. Xiao, L. Kabel, A. Uplenchwar, R. Ng, C. Ko, K. BE Stevens, RL TI Computational science research in support of petascale electromagnetic modeling - art. no. 012077 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Computational science research components were vital parts of the SciDAC-1 accelerator project and are continuing to play a critical role in the SciDAC-2 accelerator project, the Community Petascale Project for Accelerator Science and Simulation (ComPASS). Presented here are recent advances and achievements in the area of computational science research in support of petascale electromagnetic modeling for accelerator design analysis, which include shape determination of superconducting RF cavities, mesh-based multilevel preconditioner for solving highly indefinite linear systems, moving window using h- or p-refinement for time-domain short-range wakefield calculations, and improved scalable application I/O. C1 [Lee, L.; Akcelik, V.; Ge, L.; Chen, S.; Schussman, G.; Candel, A.; Li, Z.; Xiao, L.; Kabel, A.; Uplenchwar, R.; Ng, C.; Ko, K.] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Lee, L (reprint author), Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12077 EP 12077 DI 10.1088/1742-6596/125/1/012077 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700078 ER PT S AU Ligocki, TJ Schwartz, PO Percelay, J Colella, P AF Ligocki, Terry J. Schwartz, Peter O. Percelay, Julie Colella, Phillip BE Stevens, RL TI Embedded boundary grid generation using the divergence theorem, implicit functions, and constructive solid geometry - art. no. 012080 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB To construct finite-volume methods for PDEs in arbitrary dimension to arbitrary accuracy in the presence of irregular boundaries, we show that estimates of moments, integrals of monomials, over various regions are all that are needed. If implicit functions are used to represent the irregular boundary, the needed moments can be computed straightforwardly and robustly by using the divergence theorem, Taylor expansions, least squares, recursion, and ID root finding. Neither a geometric representation of the irregular boundary nor its interior is ever needed or computed. The implicit function representation is general and robust. Implicit functions can be combined via constructive solid geometry to form complex boundaries from a rich set of primitives including interpolants of sampled data, for example, 2D/3D image data and digital elevation maps. C1 [Ligocki, Terry J.; Schwartz, Peter O.; Percelay, Julie; Colella, Phillip] Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. RP Ligocki, TJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. NR 5 TC 8 Z9 8 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12080 EP 12080 DI 10.1088/1742-6596/125/1/012080 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700081 ER PT S AU Aragon, CR Bailey, SJ Poon, S Runge, K Thomas, RC AF Aragon, Cecilia R. Bailey, Stephen J. Poon, Sarah Runge, Karl Thomas, Rollin C. BE Stevens, RL TI Sunfall: a collaborative visual analytics system for astrophysics - art. no. 012091 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID SUPERNOVAE AB Computational and experimental sciences produce and collect ever-larger and complex datasets, often in large-scale, multi-institution projects. The inability to gain insight into complex scientific phenomena using current software tools is a bottleneck facing virtually all endeavors of science. In this paper, we introduce Sunfall, a collaborative visual analytics system developed for the Nearby Supernova Factory, an international astrophysics experiment and the largest data volume supernova search currently in operation. Sunfall utilizes novel interactive visualization and analysis techniques to facilitate deeper scientific insight into complex, noisy, high-dimensional, high-volume, time-critical data. The system combines novel image processing algorithms, statistical analysis, and machine learning with highly interactive visual interfaces to enable collaborative, user-driven scientific exploration of supernova image and spectral data. Sunfall is currently in operation at the Nearby Supernova Factory; it is the first visual analytics system in production use at a major astrophysics project. C1 [Aragon, Cecilia R.; Bailey, Stephen J.; Poon, Sarah; Runge, Karl; Thomas, Rollin C.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Aragon, CR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 20 TC 5 Z9 5 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12091 EP 12091 DI 10.1088/1742-6596/125/1/012091 PG 11 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700092 ER PT S AU Kamath, C AF Kamath, Chandrika BE Stevens, RL TI Sapphire: experiences in scientific data mining - art. no. 012094 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID BENT-DOUBLE GALAXIES AB The size and the complexity of the data from scientific simulations, observations, and experiments are becoming a major impediment to their analysis. To enable scientists to address this problem of data overload and benefit from their improved data collecting abilities, the Sapphire project team has been involved in the research, development, and application of scientific data mining techniques for nearly a decade. In this paper, I first describe the Sapphire system architecture that was motivated by the needs of a diverse set of applications. Then, using examples from different domains, I discuss our experiences in mining science data and some of the challenges we faced in analyzing data ranging from a megabyte to several terabytes. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Kamath, C (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 18 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12094 EP 12094 DI 10.1088/1742-6596/125/1/012094 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700095 ER PT S AU McCormick, P Anderson, E Martin, S Brownlee, C Inman, J Maltrud, M Kim, M Ahrens, J Nan, L AF McCormick, Patrick Anderson, Erik Martin, Steven Brownlee, Carson Inman, Jeff Maltrud, Mathew Kim, Mark Ahrens, James Nan, Lee BE Stevens, RL TI Quantitatively driven visualization and analysis on emerging architectures - art. no. 012095 SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE JOURNAL OF PHYSICS CONFERENCE SERIES LA English DT Proceedings Paper CT 4th Annual Scientific Discovery through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB We live in a world of ever-increasing amounts of information that is not only dynamically changing but also dramatically changing in complexity. This trend of "information overload" has quickly overwhelmed our capabilities to explore, hypothesize, and thus fully interpret the underlying details in these data. To further complicate matters, the computer architectures that have traditionally provided improved performance are undergoing a revolutionary change as manufacturers transition to building multi- and many-core processors. While these trends have the potential to lead to new scientific breakthroughs via simulation and modeling, they will do so in a disruptive manner, potentially placing a significant strain on software development activities including the overall data analysis process. In this paper we explore an approach that exploits these emerging architectures to provide an integrated environment for high-performance data analysis and visualization. C1 [McCormick, Patrick; Anderson, Erik; Martin, Steven; Brownlee, Carson; Inman, Jeff; Maltrud, Mathew; Kim, Mark; Ahrens, James; Nan, Lee] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP McCormick, P (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 20 TC 2 Z9 2 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 BP 12095 EP 12095 DI 10.1088/1742-6596/125/1/012095 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700096 ER PT S AU Amundson, JF Dechow, D McInnes, L Norris, B Spentzouris, P Stoltz, P AF Amundson, James F. Dechow, Douglas McInnes, Lois Norris, Boyana Spentzouris, Panagiotis Stoltz, Peter BE Stevens, RL TI Multiscale, multiphysics beam dynamics framework design and applications SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Modern beam dynamics simulations require nontrivial implementations of multiple physics models. We discuss how component framework design in combination with the Common Component Architecture's component model and implementation eases the process of incorporation of existing state-of-the-art models with newly-developed models. We discuss current developments in componentized beam dynamics software, emphasizing design issues and distribution issues. C1 [Amundson, James F.; Spentzouris, Panagiotis] Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. [Dechow, Douglas; Stoltz, Peter] Tech X Corp, Boulder, CO 80303 USA. [McInnes, Lois; Norris, Boyana] Argonne Natl Lab, Argonne, IL 60439 USA. RP Amundson, JF (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM amundson@fnal.gov OI Norris, Boyana/0000-0001-5811-9731 FU U.S. Department of Energy [DE-AC02- 06CH11357] FX This work was supported in part by the U.S. Department of Energy under Contract DE-AC02- 06CH11357. NR 3 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012001 DI 10.1088/1742-6596/125/1/012001 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700002 ER PT S AU Askari, E Bobaru, F Lehoucq, RB Parks, ML Silling, SA Weckner, O AF Askari, E. Bobaru, F. Lehoucq, R. B. Parks, M. L. Silling, S. A. Weckner, O. BE Stevens, RL TI Peridynamics for multiscale materials modeling SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID FINITE-ELEMENT-ANALYSIS; LONG-RANGE FORCES; MEMBRANES; MECHANICS; DYNAMICS; FIBERS AB The paper presents an overview of peridynamics, a continuum theory that employs a nonlocal model of force interaction. Specifically, the stress/strain relationship of classical elasticity is replaced by an integral operator that sums internal forces separated by a finite distance. This integral operator is not a function of the deformation gradient, allowing for a more general notion of deformation than in classical elasticity that is well aligned with the kinematic assumptions of molecular dynamics. Peridynamics effectiveness has been demonstrated in several applications, including fracture and failure of composites, nanofiber networks, and polycrystal fracture. These suggest that peridynamics is a viable multiscale material model for length scales ranging from molecular dynamics to those of classical elasticity. C1 [Askari, E.; Weckner, O.] Boeing Co, Appl Math, Seattle, WA 98124 USA. [Bobaru, F.] Univ Nebraska, Dept Mech Engn, Lincoln, NE 68588 USA. [Lehoucq, R. B.; Parks, M. L.] Sandia Natl Labs, Appl Math & Appl, Albuquerque, NM 87185 USA. [Silling, S. A.] Sandia Natl Labs, Multiscale Dynam Mat Modeling, Albuquerque, NM 87185 USA. RP Askari, E (reprint author), Boeing Co, Appl Math, Seattle, WA 98124 USA. EM abe.askari@boeing.com; fbobaru2@unl.edu; rblehou@sandia.gov; mlparks@sandia.gov; sasilli@sandia.gov; olaf.weckner@boeing.com RI Parks, Michael/A-2878-2008; Bobaru, Florin/J-2167-2012 OI Bobaru, Florin/0000-0002-9954-6489 NR 46 TC 48 Z9 49 U1 5 U2 25 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012078 DI 10.1088/1742-6596/125/1/012078 PG 11 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700079 ER PT S AU Bailey, DH Chame, J Chen, C Dongarra, J Hall, M Hollingsworth, JK Hovland, P Moore, S Seymour, K Shin, J Tiwari, A Williams, S You, H AF Bailey, David H. Chame, Jacqueline Chen, Chun Dongarra, Jack Hall, Mary Hollingsworth, Jeffrey K. Hovland, Paul Moore, Shirley Seymour, Keith Shin, Jaewook Tiwari, Ananta Williams, Sam You, Haihang BE Stevens, RL TI PERI Auto-Tuning SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The enormous and growing complexity of today's high-end systems has increased the already significant challenges of obtaining high performance on equally complex scientific applications. Application scientists are faced with a daunting challenge in tuning their codes to exploit performance-enhancing architectural features. The Performance Engineering Research Institute (PERI) is working toward the goal of automating portions of the performance tuning process. This paper describes PERI's overall strategy for auto-tuning tools and recent progress in both building auto-tuning tools and demonstrating their success on kernels, some taken from large-scale applications. C1 [Bailey, David H.; Williams, Sam] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Shin, Jaewook] Argonne Natl Lab, Argonne, IL 60439 USA. [Hollingsworth, Jeffrey K.; Tiwari, Ananta] Univ Maryland, College Pk, MD 20742 USA. [Chame, Jacqueline; Chen, Chun; Hall, Mary] Univ So Calif, Inst Informat Sci, Marina Del Rey, CA 90292 USA. [Dongarra, Jack; Moore, Shirley; Seymour, Keith; You, Haihang] Univ Tennessee, Knoxville, TN 37996 USA. RP Bailey, DH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM mhall@isi.edu FU U.S. Department of Energy [DE-AC02-06CH11357] FX This work was supported in part by the U.S. Department of Energy, under Contract DE-AC02-06CH11357. NR 8 TC 3 Z9 3 U1 0 U2 15 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012089 DI 10.1088/1742-6596/125/1/012089 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700090 ER PT S AU Baranovski, A Beattie, K Bharathi, S Boverhof, J Bresnahan, J Chervenak, A Foster, I Freeman, T Gunter, D Keahey, K Kesselman, C Kettimuthu, R Leroy, N Link, M Livny, M Madduri, R Oleynik, G Pearlman, L Schuler, R Tierney, B AF Baranovski, A. Beattie, K. Bharathi, S. Boverhof, J. Bresnahan, J. Chervenak, A. Foster, I. Freeman, T. Gunter, D. Keahey, K. Kesselman, C. Kettimuthu, R. Leroy, N. Link, M. Livny, M. Madduri, R. Oleynik, G. Pearlman, L. Schuler, R. Tierney, B. BE Stevens, RL TI Enabling petascale science: data management, troubleshooting, and scalable science services SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The Center for Enabling Distributed Petascale Science is developing serviced to enable researchers to manage large, distributed datasets. The center projects focus on three areas: tools for reliable placement of data, issues involving failure detection and failure diagnosis in distributed systems, and scalable services that process requests to access data C1 [Baranovski, A.; Oleynik, G.] Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. [Bharathi, S.; Chervenak, A.; Kesselman, C.; Pearlman, L.; Schuler, R.] Univ South Calif, Inst Informat Sci, Marina Del Rey, CA 90292 USA. [Bresnahan, J.; Foster, I.; Freeman, T.; Keahey, K.; Kettimuthu, R.; Link, M.; Madduri, R.] Univ Chicago, Inst Computat, Chicago, IL 60637 USA. [Bresnahan, J.; Foster, I.; Freeman, T.; Keahey, K.; Kettimuthu, R.; Link, M.; Madduri, R.] Argonne Natl Lab, Argonne, IL 60439 USA. [Bresnahan, J.; Foster, I.; Freeman, T.; Keahey, K.; Kettimuthu, R.; Link, M.; Madduri, R.] Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. [Foster, I.] Univ Chicago, Dept Comp Sci, Chicago, IL 60637 USA. [Beattie, K.; Boverhof, J.; Gunter, D.; Tierney, B.] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Leroy, N.; Livny, M.] Univ Wisconsin, Dept Comp Sci, Madison, WI 53719 USA. RP Baranovski, A (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM annc@isi.edu OI Kesselman, Carl/0000-0003-0917-1562 FU Department of Energy's Scientific Discovery [DE-FC02-06ER25757]; Office of Advanced Scientific Computing Research; Office of Science, U.S. Department of Energy [DE-AC03-76SF00098, DE-AC02-06CH11357] FX This work was supported in part by the Department of Energys Scientific Discovery through AdvancedComputing 2 program under grant DE-FC02-06ER25757 and by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under contracts DE-AC03-76SF00098 and DE-AC02-06CH11357. NR 14 TC 0 Z9 0 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012068 DI 10.1088/1742-6596/125/1/012068 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700069 ER PT S AU Batchelor, D Abla, G Bateman, G Bernholdt, D Berry, L Bonoli, P Bramley, R Breslau, J Chance, M Chen, J Choi, M Elwasif, W Fu, G Harvey, R Jaeger, E Jardin, S Jenkins, T Keyes, D Klasky, S Kruger, S Ku, L Lynch, V McCune, D Ramos, J Schissel, D Schnack, D Wright, J AF Batchelor, D. Abla, G. Bateman, G. Bernholdt, D. Berry, L. Bonoli, P. Bramley, R. Breslau, J. Chance, M. Chen, J. Choi, M. Elwasif, W. Fu, G. Harvey, R. Jaeger, E. Jardin, S. Jenkins, T. Keyes, D. Klasky, S. Kruger, S. Ku, L. Lynch, V. McCune, D. Ramos, J. Schissel, D. Schnack, D. Wright, J. BE Stevens, RL TI Simulation of wave interactions with MHD SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The broad scientific objectives of the SWIM (Simulation of Wave Interaction with MHD) project are twofold: (1) improve our understanding of interactions that both radio frequency (RF) wave and particle sources have on extended-MHD phenomena, and to substantially improve our capability for predicting and optimizing the performance of burning plasmas in devices such as ITER: and (2) develop an integrated computational system for treating multiphysics phenomena with the required flexibility and extensibility to serve as a prototype for the,Fusion Simulation Project. The Integrated Plasma Simulator (IPS) has been implemented. Presented here are initial physics results on RF effects on MHD instabilities in tokamaks as well as simulation results for tokamak discharge evolution using the IPS. C1 [Batchelor, D.; Bernholdt, D.; Berry, L.; Elwasif, W.; Jaeger, E.; Klasky, S.; Lynch, V.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. [Abla, G.; Choi, M.; Schissel, D.] Gen Atom, San Diego, CA 92186 USA. [Bateman, G.] Lehigh Univ, Bethlehem, PA 18015 USA. [Bonoli, P.; Ramos, J.; Wright, J.] MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. [Bramley, R.] Indiana Univ, Bloomington, IN 47405 USA. [Breslau, J.; Chance, M.; Chen, J.; Fu, G.; Jardin, S.; Ku, L.; McCune, D.] Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. [Harvey, R.] CompX, Del Mar, CA 92014 USA. [Keyes, D.] Columbia Univ, New York, NY 10027 USA. [Kruger, S.] Tech X, Boulder, CO 80303 USA. [Jenkins, T.; Schnack, D.] Univ Wisconsin, Madison, WI 53706 USA. RP Batchelor, D (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM batchelordb@ornl.gov RI Lynch, Vickie/J-4647-2012 OI Lynch, Vickie/0000-0002-5836-7636 NR 0 TC 3 Z9 3 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012039 DI 10.1088/1742-6596/125/1/012039 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700040 ER PT S AU Boman, EG Bozdag, D Catalyurek, UV Devine, KD Gebremedhin, AH Hovland, PD Pothen, A AF Boman, Erik G. Bozdag, Doruk Catalyurek, Umit V. Devine, Karen D. Gebremedhin, Assefaw H. Hovland, Paul D. Pothen, Alex BE Stevens, RL TI Combinatorial algorithms for computational science and engineering SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB We discuss recent activities in the SciDAC Applied Mathematics Institute for Combinatorial Scientific Computing and Petascale Simulations (CSCAPES). C1 [Boman, Erik G.; Devine, Karen D.] Sandia Natl Labs, Discrete Algorithms & Math Dept, POB 5800, Albuquerque, NM 87185 USA. [Bozdag, Doruk; Catalyurek, Umit V.] Ohio State Univ, Columbus, OH 43210 USA. [Gebremedhin, Assefaw H.; Pothen, Alex] Purdue Univ, Dept Comp Sci, Ctr Res Inst, W Lafayette, IN 47907 USA. [Hovland, Paul D.] Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. RP Boman, EG (reprint author), Sandia Natl Labs, Discrete Algorithms & Math Dept, POB 5800, Albuquerque, NM 87185 USA. RI Catalyurek, Umit/A-2454-2008; OI Catalyurek, Umit/0000-0002-5625-3758; Pothen, Alex/0000-0002-3421-3325 FU U. S. Department of Energy's National Nuclear Security Administration [DE-AC04-94AL85000]; Office of Advanced Scientific Computing Research; U.S. Department of Energy [W-31-109-Eng-38]; U.S. Department of Energy's Office of Science [DE-FC-0206-ER-25774] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the U. S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. The work at Argonne was supported by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, U.S. Department of Energy under Contract W-31-109-Eng-38. The CSCAPES Institute is supported by the U.S. Department of Energy's Office of Science through grant DE-FC-0206-ER-25774, as part of its SciDAC program. NR 11 TC 0 Z9 0 U1 0 U2 9 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012071 DI 10.1088/1742-6596/125/1/012071 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700072 ER PT S AU Bulgac, A Roche, KJ AF Bulgac, Aurel Roche, Kenneth J. BE Stevens, RL TI Time-dependent density functional theory applied to superfluid nuclei SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB We describe the response of superfluid nuclei to any external time-dependent probe within an extension of the density functional theory, the time-dependent superfluid local density approximation (TD-SLDA). All quasi-particle wave functions (qpwfs) are represented on a three-dimensional spatial grid to allow for the breaking of all possible symmetries, and subsequently these functions are evolved in time using a high order multi-step algorithm. Mathematically this problem is a system of coupled, time-dependent, nonlinear partial differential equations, which when discretized becomes equivalent to a nonlinear classical mechanics problem with proportional to N-x(6) approximate to 10(12) degrees of freedom, where N-x is number of spatial mesh points in one direction. The lattice representation of the qpwfs allows for fast and accurate evaluation of various spatial derivatives required for the construction of various physical quantities that appear in the theory. The total number of independent qpwfs is of the order of spatial mesh points, and the system is evolved for tens to hundreds of thousands of time steps. We describe how we implemented the TD-SLDA method and report some of the challenges encountered. C1 [Bulgac, Aurel] Univ Washington, Dept Phys, Seattle, WA 98195 USA. [Roche, Kenneth J.] Oak Ridge Natl Lab, Comp Sci & Math Div, POB 2008, Oak Ridge, TN 37831 USA. RP Bulgac, A (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. EM bulgac@phys.washington.edu; rochekj@ornl.gov FU Office of Advanced Scientific Computing Research; U.S. Department of Energy; Oak Ridge National Laboratory; UT-Battelle, LLC [De-AC05-00OR22725]; [DEFC02-07ER41457] FX We thank Y. Yu for major help at the initial stages of coding the theory and the UNEDF SciDAC collaboration for support through the US Department of Energy under grant No. DEFC02-07ER41457. This research is sponsored by the Office of Advanced Scientific Computing Research; U.S. Department of Energy. The work was performed at the Oak Ridge National Laboratory, which is managed by UT-Battelle, LLC under Contract No. De-AC05-00OR22725. NR 9 TC 11 Z9 11 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012064 DI 10.1088/1742-6596/125/1/012064 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700065 ER PT S AU Canning, A Marques, O Voemel, C Wang, LW Dongarra, J Langou, J Tomov, S AF Canning, A. Marques, O. Voemel, C. Wang, Lin-Wang Dongarra, J. Langou, J. Tomov, S. BE Stevens, RL TI New eigensolvers for large-scale nanoscience simulations SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID ENERGY AB We present results for applications to nanosystems of state-of-the-art iterative eigensolvers based on conjugate gradients and variants of Davidson in the context of semi-empirical plane wave electronic structure calculations. We are concerned with the computation of electronic and optical properties of nanosystems using the Energy SCAN method to compute interior eigenstates around the band gap that determine their properties. Numerically, this interior Hermitian eigenvalue problem poses several challenges, with respect to both accuracy and efficiency. All the iterative eigensolvers are seeking the minimal eigenvalues of the folded operator with reference shift in the band-gap. The tested methods include standard conjugate-gradient (CG)-based Rayleigh quotient minimization, Locally optimal block-preconditioned CG (LOBPCG) and two variants of the (Jacobi-)Davidson method: JDQMR and GD+1. Our experimental results indicated that Davidson-type methods are often the fastest. C1 [Canning, A.; Marques, O.; Voemel, C.; Wang, Lin-Wang] Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. [Dongarra, J.; Langou, J.; Tomov, S.] Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. RP Canning, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Computat Res Div, Berkeley, CA 94720 USA. EM acanning@lbl.gov NR 8 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012074 DI 10.1088/1742-6596/125/1/012074 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700075 ER PT S AU Chang, CS Klasky, S Cummings, J Samtaney, R Shoshani, A Sugiyama, L Keyes, D Ku, S Park, G Parker, S Podhorszki, N Strauss, H Abbasi, H Adams, M Barreto, R Bateman, G Bennett, K Chen, Y Azevedo, ED Docan, C Ethier, S Feibush, E Greengard, L Hahm, T Hinton, F Jin, C Khan, A Kritz, A Krsti, P Lao, T Lee, W Lin, Z Lofstead, J Mouallem, P Nagappan, M Pankin, A Parashar, M Pindzola, M Reinhold, C Schultz, D Schwan, K Silver, D Sim, A Stotler, D Vouk, M Wolf, M Weitzner, H Worley, P Xiao, Y Yoon, E Zorin, D AF Chang, C. S. Klasky, S. Cummings, J. Samtaney, R. Shoshani, A. Sugiyama, L. Keyes, D. Ku, S. Park, G. Parker, S. Podhorszki, N. Strauss, H. Abbasi, H. Adams, M. Barreto, R. Bateman, G. Bennett, K. Chen, Y. Azevedo, E. D' Docan, C. Ethier, S. Feibush, E. Greengard, L. Hahm, T. Hinton, F. Jin, C. Khan, A. Kritz, A. Krsti, P. Lao, T. Lee, W. Lin, Z. Lofstead, J. Mouallem, P. Nagappan, M. Pankin, A. Parashar, M. Pindzola, M. Reinhold, C. Schultz, D. Schwan, K. Silver, D. Sim, A. Stotler, D. Vouk, M. Wolf, M. Weitzner, H. Worley, P. Xiao, Y. Yoon, E. Zorin, D. BE Stevens, RL TI Toward a first-principles integrated simulation of tokamak edge plasmas SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Performance of the ITER is anticipated to be highly sensitive to the edge plasma condition. The edge pedestal in ITER needs to be predicted from an integrated simulation of the necessary first-principles, multi-scale physics codes. The mission of the SciDAC Fusion Simulation Project (FSP) Prototype Center for Plasma Edge Simulation (CPES) is to deliver such a code integration framework by (1) building new kinetic codes XGC0 and XGC1, which can simulate the edge pedestal buildup; (2) using and improving the existing MHD codes ELITE, M3D-OMP, M3D-MPP and NIMROD, for study of large-scale edge instabilities called Edge Localized Modes (ELMs); and (3) integrating the codes into a framework using cutting-edge computer science technology. Collaborative effort among physics, computer science, and applied mathematics within CPES has created the first working version of the End-to-end Framework for Fusion Integrated Simulation (EFFIS), which can be used to study the pedestal-ELM cycles. C1 [Chang, C. S.; Ku, S.; Park, G.; Strauss, H.; Greengard, L.; Weitzner, H.; Zorin, D.] NYU, 550 1St Ave, New York, NY 10012 USA. [Klasky, S.; Podhorszki, N.; Barreto, R.; Azevedo, E. D'; Krsti, P.; Reinhold, C.; Schultz, D.; Worley, P.] Oak Ridge Natl Lab, Oak Ridge, TN 37381 USA. [Cummings, J.] CALTECH, Pasadena, CA 91125 USA. [Samtaney, R.; Ethier, S.; Feibush, E.; Hahm, T.; Lee, W.; Stotler, D.; Yoon, E.] Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. [Shoshani, A.; Sim, A.] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Sugiyama, L.] MIT, Cambridge, MA 02139 USA. [Keyes, D.; Adams, M.; Lao, T.] Columbia Univ, New York, NY 10027 USA. [Parker, S.; Chen, Y.] Univ Colorado, Boulder, CO 80309 USA. [Abbasi, H.; Schwan, K.; Wolf, M.] Georgia Inst Technol, Atlanta, GA 30332 USA. [Bateman, G.; Kritz, A.] Lehigh Univ, Bethlehem, PA 18015 USA. [Bennett, K.; Parashar, M.] Rutgers State Univ, New Brunswick, NJ 08901 USA. [Hinton, F.] Hinton Assoc, New Cumberland, PA USA. [Khan, A.] Univ Utah, Salt Lake City, UT 84112 USA. [Xiao, Y.] Univ Calif Irvine, Irvine, CA 92967 USA. [Mouallem, P.; Nagappan, M.; Vouk, M.] North Carolina State Univ, Raleigh, NC 27695 USA. [Pindzola, M.] Auburn Univ, Auburn, AL 36849 USA. RP Chang, CS (reprint author), NYU, 550 1St Ave, New York, NY 10012 USA. EM cschang@cims.nyq.edu; klasky@ornl.gov RI Ku, Seung-Hoe/D-2315-2009; Stotler, Daren/J-9494-2015 OI Ku, Seung-Hoe/0000-0002-9964-1208; Stotler, Daren/0000-0001-5521-8718 FU US DOE Office of Fusion Energy Science and Office of Advanced Scientific Computing Research FX This work is jointly supported by US DOE Office of Fusion Energy Science and Office of Advanced Scientific Computing Research. NR 14 TC 10 Z9 10 U1 2 U2 14 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012042 DI 10.1088/1742-6596/125/1/012042 PG 9 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700043 ER PT S AU Chang, CH Graf, P Alber, DM Kim, K Murray, G Posewitz, M Seibert, M AF Chang, Christopher H. Graf, Peter Alber, David M. Kim, Kwiseon Murray, Glenn Posewitz, Matthew Seibert, Michael BE Stevens, RL TI Photons, photosynthesis, and high-performance computing: challenges, progress, and promise of modeling metabolism in green algae SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID OXIDATIVE-PHOSPHORYLATION; CHLAMYDOMONAS-REINHARDTII; GENE; NETWORKS; SBML; RECONSTRUCTION; ONTOLOGY; LIBRARY; ENZYMES; BIOLOGY AB The complexity associated with biological metabolism considered at a kinetic level presents a challenge to quantitative modeling. In particular, the relatively sparse knowledge of parameters for enzymes with known kinetic responses is problematic. The possible space of these parameters is of high-dimension, and sampling of such a space typifies a combinatorial explosion of possible dynamic states. However, with sufficient quantitative transcriptomics, proteomics, and metabolomics data at hand, these challenges could be met by high-performance software with sampling, fitting, and optimization capabilities. With this in mind, we present the High-Performance Systems Biology Toolkit HiPer SBTK, an evolving software package to simulate, fit, and optimize metabolite concentrations and fluxes within the space of rate and binding parameters associated with detailed enzyme kinetic models. We present our chosen modeling paradigm for the formulation of metabolic pathway models, the means to address the challenge of representing such models in a precise and persistent fashion using the standardized Systems Biology Markup Language, and our second-generation model of H-2-associated Chlamydomonas metabolism. Processing of such models for hierarchically parallelized simulation and optimization, job specification by the user through a GUI interface, software capabilities and initial scaling data, and the mapping of the computation to biological questions is also discussed. Moreover, we present near-term future software and model development goals. C1 [Chang, Christopher H.; Graf, Peter; Alber, David M.; Kim, Kwiseon] Natl Renewable Energy Lab, Mat & Computat Sci Ctr, 1617 Cole Blvd, Golden, CO 80401 USA. [Murray, Glenn; Posewitz, Matthew] Colorado Sch Mines, Golden, CO 80401 USA. [Seibert, Michael] Natl Renewable Energy Lab, Energy Sci Directorate, Golden, CO 80401 USA. RP Chang, CH (reprint author), Natl Renewable Energy Lab, Mat & Computat Sci Ctr, 1617 Cole Blvd, Golden, CO 80401 USA. EM christopher_chang@nrel.gov NR 33 TC 2 Z9 2 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012048 DI 10.1088/1742-6596/125/1/012048 PG 13 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700049 ER PT S AU Colella, P Graves, D Ligocki, T Trebotich, D Van Straalen, B AF Colella, Phillip Graves, Dan Ligocki, Terry Trebotich, David Van Straalen, Brian BE Stevens, RL TI Embedded boundary algorithms and software for partial differential equations SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID PROJECTION METHOD; HEAT-EQUATION AB In this paper, we give an overview of a set of methods being developed for solving classical PDEs in irregular geometries, or in the presence of free boundaries. In this approach, the irregular geometry is represented on a rectangular grid by specifying the intersection of each grid cell with the region on one or the other side of the boundary. This leads to a natural conservative discretization of the solution to the PDE on either side of the boundary. Stable and robust hyperbolic and linear elliptic/parabolic solvers have been designed and implemented. Example applications of this approach are shown for compressible and incompressible gas dynamics problems in complex geometries, and for surface diffusion in a cell membrane. C1 [Colella, Phillip; Graves, Dan; Ligocki, Terry; Van Straalen, Brian] Univ Calif Berkeley, Lawrence Berkeley Lab, Appl Numer Algorithms Grp, Berkeley, CA 94720 USA. [Trebotich, David] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Colella, P (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Appl Numer Algorithms Grp, Berkeley, CA 94720 USA. EM bvstraalen@lbl.gov FU Lawrence Berkeley National Laboratory [DE-AC02-05CH1123]; Lawrence Livermore National Laboratory [DEAC52-07NA27344] FX Research supported by the Office of Advanced Scientific Computing Research of the US Department of Energy at the Lawrence Berkeley National Laboratory under contract number DE-AC02-05CH1123, and at the Lawrence Livermore National Laboratory under contract DEAC52-07NA27344. NR 14 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012084 DI 10.1088/1742-6596/125/1/012084 PG 8 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700085 ER PT S AU Crowley, MF Uberbacher, EC Brooks, CL Walker, RC Nimlos, MR Himmel, ME AF Crowley, M. F. Uberbacher, E. C. Brooks, C. L., III Walker, R. C. Nimlos, M. R. Himmel, M. E. BE Stevens, RL TI Developing improved MD codes for understanding processive cellulases SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID MOLECULAR-DYNAMICS; BIOFUELS AB The mechanism of action of cellulose-degrading enzymes is illuminated through a multidisciplinary collaboration that uses molecular dynamics (MD) simulations and expands the capabilities of MD codes to allow simulations of enzymes and substrates on petascale computational facilities. There is a class of glycoside hydrolase enzymes called cellulases that are thought to decrystallize and processively depolymerize cellulose using biochemical processes that are largely not understood. Understanding the mechanisms involved and improving the efficiency of this hydrolysis process through computational models and protein engineering presents a compelling grand challenge. A detailed understanding of cellulose structure, dynamics and enzyme function at the molecular level is required to direct protein engineers to the right modifications or to understand if natural thermodynamic or kinetic limits are in play. Much can be learned about processivity by conducting carefully designed molecular dynamics (MD) simulations of the binding and catalytic domains of cellulases with various substrate configurations, solvation models and thermodynamic protocols. Most of these numerical experiments, however, will require significant modification of existing code and algorithms in order to efficiently use current (terascale) and future (petascale) hardware to the degree of parallelism necessary to simulate a system of the size proposed here. This work will develop MD codes that can efficiently use terascale and petascale systems, not just for simple classical MD simulations, but also for more advanced methods, including umbrella sampling with complex restraints and reaction coordinates, transition path sampling, steered molecular dynamics, and quantum mechanical/molecular mechanical simulations of systems the size of cellulose degrading enzymes acting on cellulose. C1 [Crowley, M. F.; Nimlos, M. R.; Himmel, M. E.] Natl Renewable Energy Lab, Golden, CO 80401 USA. [Uberbacher, E. C.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. [Brooks, C. L., III] Univ Michigan, Ann Arbor, MI 48109 USA. [Walker, R. C.] San Diego Supercomp Ctr, La Jolla, CA 92093 USA. RP Crowley, MF (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI crowley, michael/A-4852-2013 OI crowley, michael/0000-0001-5163-9398 FU U.S. Department of Energy Office of Science through a SciDAC FX This work is performed with support from the U.S. Department of Energy Office of Science through a SciDAC award titled Understanding the Processivity of Cellobiohydrolase I. NR 15 TC 2 Z9 2 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012049 DI 10.1088/1742-6596/125/1/012049 PG 7 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700050 ER PT S AU Dahlgren, TL Bernholdt, DE McInnes, LC AF Dahlgren, Tamara L. Bernholdt, David E. McInnes, Lois Curfman BE Stevens, RL TI Gaining confidence in scientific applications through executable interface contracts SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Interface contract enforcement is intended to help scientists gain confidence in software built from third-party components. Unfamiliar components present increased risk of incorrect or unanticipated usage patterns and unexpected component behavior. Executable interface contracts can address these issues but may incur unacceptable overhead. Research into techniques for p erformance-driven contract enforcement pursues practical solutions to adapting the level of contract enforcement to performance constraints. C1 [Dahlgren, Tamara L.] Lawrence Livermore Natl Lab, Berkeley, CA 94720 USA. [Bernholdt, David E.] Oak Ridge Natl Lab, Dept Comp Sci & Math, Oak Ridge, TN 37831 USA. [McInnes, Lois Curfman] Argonne Natl Lab, Dept Math & Comp Sci, Argonne, IL 60439 USA. RP Dahlgren, TL (reprint author), Lawrence Livermore Natl Lab, Berkeley, CA 94720 USA. EM dahlgren1@llnl.gov; bernholdtde@ornl.gov; mcinnes@mcs.anl.gov FU U. S. Department of Energy's Scientific Discovery; Lawrence Livermore National Security, LLC [DE-AC52-07NA27344]; UT-Battelle, LLC [DE-AC-05- 00OR22725]; Argonne National Laboratory [DE-AC02-06CH11357] FX We thank those who contributed software and/or interface contracts to the studies: Lori Freitag Diachin (simplicial mesh), Carl Ollivier-Gooch (volume mesh, program MT), and Kyle Chand. This work was performed under the auspices of the U. S. Department of Energys Scientific Discovery through Advanced Computing (SciDAC) programs Center for Technology for Advanced Scientific Component Software (TASCS). Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC under Contract DE-AC52-07NA27344. Oak Ridge National Laboratory is managed by UT-Battelle, LLC under Contract DE-AC-05- 00OR22725. Argonne National Laboratory operates under Contract DE-AC02-06CH11357. NR 15 TC 1 Z9 1 U1 0 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012086 DI 10.1088/1742-6596/125/1/012086 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700087 ER PT S AU Endeve, E Cardall, CY Budiardja, RD Mezzacappa, A AF Endeve, E. Cardall, C. Y. Budiardja, R. D. Mezzacappa, A. BE Stevens, RL TI Magnetic field generation by the stationary accretion shock instability SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID COLLAPSE SUPERNOVA EXPLOSIONS; CONSTRAINED TRANSPORT METHOD; SPECTRAL NEUTRINO TRANSPORT; CONSERVATION-LAWS; CORE; SIMULATIONS; SCHEMES; CONVECTION; STARS AB By adding a weak magnetic field to a spherically symmetric fluid configuration that caricatures a stalled shock in the post-bounce supernova environment, we explore the capacity of the stationary accretion shock instability (SASI) to generate magnetic fields. The SASI develops upon perturbation of the initial condition, and the ensuing flow generates - in the absence of rotation - dynamically significant magnetic fields (similar to 10(15) G) on a time scale that is relevant for the explosion mechanism of core collapse supernovae. We describe our model, present some recent results, and discuss their potential relevance for supernova models. C1 [Endeve, E.; Cardall, C. Y.; Mezzacappa, A.] Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. [Endeve, E.; Cardall, C. Y.; Budiardja, R. D.] Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. [Endeve, E.] Joint Inst Heavy Ion Res, Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Endeve, E (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. EM endevee@ornl.gov RI Mezzacappa, Anthony/B-3163-2017; OI Mezzacappa, Anthony/0000-0001-9816-9741; Endeve, Eirik/0000-0003-1251-9507 FU Oak Ridge National Laboratory (ORNL); UT-Battelle; LLC; DoE [DE-AC05-00OR22725]; National Center for Computational Sciences at ORNL; Office of Science of the U.S. Department of Energy [DEAC05-00OR22725] FX This work was supported by Oak Ridge National Laboratory (ORNL), managed by UT-Battelle, LLC, for the DoE under contract DE-AC05-00OR22725. This research used resources of the National Center for Computational Sciences at ORNL, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DEAC05-00OR22725. NR 15 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012006 DI 10.1088/1742-6596/125/1/012006 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700007 ER PT S AU Fowler, RJ Gamblin, T Porterfield, AK Dreher, P Huang, S Joo, B AF Fowler, R. J. Gamblin, T. Porterfield, A. K. Dreher, P. Huang, S. Joo, B. BE Stevens, RL TI Performance engineering challenges: the view from RENCI SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Trends in chip technology and system design are causing a revolution in high-performance computing. The emergence of multicore processor chips, the construction of very large computing systems, and the increasing need to deal with power and energy issues in these systems are three of the most significant changes. We focus on the way that these trends have created a new set of challenges in the area of performance engineering, the measurement, analysis, and tuning of computing systems and applications. We discuss these changes and outline recent work at the Renaissance Computing Institute to meet these challenges. C1 [Fowler, R. J.; Gamblin, T.; Porterfield, A. K.; Dreher, P.; Huang, S.] Univ N Carolina, Renaissance Comp Inst, Chapel Hill, NC 27516 USA. [Joo, B.] Thomas Jefferson Natl Lab, Newport News, VA 23606 USA. RP Fowler, RJ (reprint author), Univ N Carolina, Renaissance Comp Inst, Chapel Hill, NC 27516 USA. EM rjf@renci.org; tgamblin@cs.unc.edu; akp@renci.org FU DOE [DE-FC02-06ER25764, DE-FC02-06ER41445] FX This work was supported by the DOE SciDAC program under award numbers DE-FC02-06ER25764 (PERI) and DE-FC02-06ER41445. NR 11 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012065 DI 10.1088/1742-6596/125/1/012065 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700066 ER PT S AU Geddes, CGR Bruhwiler, DL Cary, JR Mori, WB Vay, JL Martins, SF Katsouleas, T Cormier-Michel, E Fawley, WM Huang, C Wang, X Cowan, B Decyk, VK Esarey, E Fonseca, RA Lu, W Messmer, P Mullowney, P Nakamura, K Paul, K Plateau, GR Schroeder, CB Silva, LO Toth, C Tsung, FS Tzoufras, M Antonsen, T Vieira, J Leemans, WP AF Geddes, C. G. R. Bruhwiler, D. L. Cary, J. R. Mori, W. B. Vay, J-L Martins, S. F. Katsouleas, T. Cormier-Michel, E. Fawley, W. M. Huang, C. Wang, X. Cowan, B. Decyk, V. K. Esarey, E. Fonseca, R. A. Lu, W. Messmer, P. Mullowney, P. Nakamura, K. Paul, K. Plateau, G. R. Schroeder, C. B. Silva, L. O. Toth, Cs Tsung, F. S. Tzoufras, M. Antonsen, T. Vieira, J. Leemans, W. P. BE Stevens, RL TI Computational studies and optimization of wakefield accelerators SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID COLLIDING LASER-PULSES; ELECTRON-BEAMS; PLASMA; CODE; RADIATION; INJECTION AB Laser- and particle beam-driven plasma wakefield accelerators produce accelerating fields thousands of times higher than radio-frequency accelerators, offering compactness and ultrafast bunches to extend the frontiers of high energy physics and to enable laboratory-scale radiation sources. Large-scale kinetic simulations provide essential understanding of accelerator physics to advance beam performance and stability and show and predict the physics behind recent demonstration of narrow energy spread bunches. Benchmarking between codes is establishing validity of the models used and, by testing new reduced models, is extending the reach of simulations to cover upcoming meter-scale multi-GeV experiments. This includes new models that exploit Lorentz boosted simulation frames to speed calculations. Simulations of experiments showed that recently demonstrated plasma gradient injection of electrons can be used as an injector to increase beam quality by orders of magnitude. Simulations are now also modeling accelerator stages of tens of GeV, staging of modules, and new positron sources to design next-generation experiments and to use in applications in high energy physics and light sources. C1 [Geddes, C. G. R.; Vay, J-L; Cormier-Michel, E.; Fawley, W. M.; Esarey, E.; Nakamura, K.; Plateau, G. R.; Schroeder, C. B.; Toth, Cs; Leemans, W. P.] Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Bruhwiler, D. L.; Cary, J. R.; Cowan, B.; Messmer, P.; Mullowney, P.; Paul, K.] Tech-X Corporation, Boulder, CO 80303 USA. [Cary, J. R.] Univ Colorado, Boulder, CO 80309 USA. [Mori, W. B.; Huang, C.; Decyk, V. K.; Lu, W.; Tsung, F. S.; Tzoufras, M.] Univ Calif Los Angeles, Los Angeles, CA 90095 USA. [Antonsen, T.] Univ Maryland, College Pk, MD 20742 USA. [Katsouleas, T.; Wang, X.] Univ Southern Calif, Los Angeles, CA 90089 USA. [Martins, S. F.; Fonseca, R. A.; Silva, L. O.] GoLP IPFN Inst Super Tecn, Lisbon 1049001, Portugal. RP Geddes, CGR (reprint author), Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Silva, Luis/C-3169-2009; Fonseca, Ricardo/B-7680-2009; Tzoufras, Michail/C-6436-2009; Vieira, Jorge/M-4373-2013; Lu, Wei/F-2504-2016; OI Silva, Luis/0000-0003-2906-924X; Fonseca, Ricardo/0000-0001-6342-6226; Vieira, Jorge/0000-0002-5515-3624; Schroeder, Carl/0000-0002-9610-0166 FU U.S. Department of Energy (DOE) Office of Science; Office of High Energy Physics SciDAC program; LBL [DE AC02-05CH11231, DE-FG03- 95ER40926, DE-FG02-01ER41178, DE-FG02 03ER83857]; USC [DE-FG03-92ER40745]; UCLA [DE-FG03-92ER40727, DE-FG02-07ER41500, DE-FG0203ER54721]; TX [DE-FC02-07ER41499, DE-FG02-07ER84834, DE-FG02-04ER84097, DE-FG0204ER41317]; U.S.-LHC Accelerator Research Program (LARP); Office of Nuclear Physics [DE-FG02-05ER84173]; DARPA; NSF [0113907, 0614001]; FCT Portugal; National Energy Research Scientific Computing Center; DOE Office of Science [DE-AC02 05CH11231]; DAWSON Cluster [NSF Phy-0321345]; LLNL ATLAS FX Work supported by the U.S. Department of Energy (DOE) Office of Science, Office of High Energy Physics SciDAC program and under grants including LBL DE AC02-05CH11231, DE-FG03- 95ER40926, DE-FG02-01ER41178, DE-FG02 03ER83857, USC DE-FG03-92ER40745 UCLA DE-FG03-92ER40727, DE-FG02-07ER41500,DE-FG0203ER54721, TX DE-FC02-07ER41499,DE-FG02-07ER84834, DE-FG02-04ER84097, DE-FG0204ER41317. Support also comes from the U.S.-LHC Accelerator Research Program (LARP), Office of Nuclear Physics grant DE-FG02-05ER84173, DARPA, from NSF grants 0113907 and 0614001, and from FCT Portugal. This work used the resources of the National Energy Research Scientific Computing Center, which is supported by the DOE Office of Science under Contract No. DE-AC02 05CH11231 as well as the DAWSON Cluster under NSF Phy-0321345 and the LLNL ATLAS facility NR 44 TC 16 Z9 16 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012002 DI 10.1088/1742-6596/125/1/012002 PG 11 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700003 ER PT S AU Hammond, GE Lichtner, PC Milis, RT Lu, C AF Hammond, Glenn E. Lichtner, Peter C. Milis, Richard Tran Lu, Chuan BE Stevens, RL TI Toward petascale computing in geosciences: application to the Hanford 300 Area SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Modeling uranium transport at the Hanford 300 Area presents new challenges for high performance computing. A field-scale three-dimensional domain with an hourly fluctuating Columbia river stage coupled to flow in highly permeable sediments results in fast groundwater flow rates requiring small time steps. In this work, high-performance computing has been applied to simulate variably saturated groundwater flow and tracer transport at the 300 Area using PFLOTRAN. Simulation results are presented for discretizations up to 10.8 million degrees of freedom, while PFLOTRAN performance was assessed on up to one billion degrees of freedom and 12,000 processor cores on Jaguar, the Cray XT4 supercomputer at ORNL. C1 [Hammond, Glenn E.] Pacific NW Natl Lab, Environm Technol Div, Hydrol Grp, Richland, WA 99352 USA. RP Hammond, GE (reprint author), Pacific NW Natl Lab, Environm Technol Div, Hydrol Grp, Richland, WA 99352 USA. EM glenn.hammond@pnl.gov; lichtner@lanl.gov; rmills@ornl.gov; clu@egi.utah.edu NR 8 TC 4 Z9 4 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012051 DI 10.1088/1742-6596/125/1/012051 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700052 ER PT S AU Hereld, M Olson, E Papka, ME Uram, TD AF Hereld, M. Olson, E. Papka, M. E. Uram, T. D. BE Stevens, RL TI Streaming visualization for collaborative environments SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Connecting expensive and scarce visual data analysis resources to end-users is a major challenge today. We describe a flexible mechanism for meeting this challenge based on commodity compression technologies for streaming video. The advantages of this approach include simplified application development, access to generic client components for viewing, and simplified incorporation of improved codecs as they become available. In this paper we report newly acquired experimental results for two different applications being developed to exploit this approach and test its merits. One is based on a new plugin for ParaView that adds video streaming cleanly and transparently to existing applications. The other is a custom volume rendering application with new remote capabilities. Using typical datasets under realistic conditions, we find the performance for both is satisfactory. C1 [Hereld, M.; Papka, M. E.; Uram, T. D.] Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. [Olson, E.] Univ Chicago, Chicago, IL 60637 USA. RP Hereld, M (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. EM papka@anl.gov OI Hereld, Mark/0000-0002-0268-2880 FU Office of Advanced Scientific Computing Research; Office of Science, U.S. Department of Energy [DE-AC02-06CH11357]; National Institutes of Health/National Library of Medicine [N01-LM-3-3508]; National Science Foundation [ANI-01-22296] FX We acknowledge Joseph Insley for his help in this work; the University of Chicago TeraGrid RP support team; and the Australian National University for its modified h261 codec. This work has been supported in part by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S. Department of Energy, under Contract DE-AC02-06CH11357. Additional supported provided by the National Institutes of Health/National Library of Medicine, under Contract N01-LM-3-3508 and the National Science Foundation under Grant No. ANI-01-22296. NR 7 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012097 DI 10.1088/1742-6596/125/1/012097 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700098 ER PT S AU Jardin, SC Ferraro, N Luo, X Chen, J Breslau, J Jansen, KE Shephard, MS AF Jardin, S. C. Ferraro, N. Luo, X. Chen, J. Breslau, J. Jansen, K. E. Shephard, M. S. BE Stevens, RL TI The M3DC(1) approach to simulating 3D 2-fluid magnetohydrodynamics in magnetic fusion experiments SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID FINITE-ELEMENT; EQUATIONS AB A new approach for solving the 3D MHD equations in a strongly magnetized toroidal plasma is presented which uses high-order 2D finite elements with C, continuity. The vector fields use a physics-based decomposition. An efficient implicit time advance separates the velocity and field advance. ITAPS (SCOREC) adaptivity software and TOPS solvers are used. C1 [Jardin, S. C.; Ferraro, N.; Chen, J.; Breslau, J.] Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. [Luo, X.; Jansen, K. E.; Shephard, M. S.] Rensselaer Polytech Inst, Sci Comp Res Ctr, Troy, NY 12180 USA. RP Jardin, SC (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. EM jardin@pppl.gov OI Ferraro, Nathaniel/0000-0002-6348-7827 FU U.S. DoE [DE-FC02-06ER25760, DE-AC02-76CH03073] FX This work was supported by U.S. DoE contracts DE-FC02-06ER25760 and DE-AC02-76CH03073. The authors benefitted from discussions with Drs. M. Chance, G. Fu, W. Park, H. Strauss, and L. Sugiyama, and from discussions and assistance from Drs. A. Bauer and Y.S. Li. NR 16 TC 8 Z9 8 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012044 DI 10.1088/1742-6596/125/1/012044 PG 7 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700045 ER PT S AU Kasen, D Thomas, RC Ropke, F Woosley, SE AF Kasen, Daniel Thomas, R. C. Roepke, Fritz Woosley, S. E. BE Stevens, RL TI Multidimensional radiative transfer calculations of the light curves and spectra of Type Ia supernovae SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID DELAYED-DETONATION MODEL; SPECTROPOLARIMETRY; ASPHERICITY; EXPLOSION; STAR AB The explosion of a white dwarf star in a Type Ia supernova (SN Ia) explosion leads to the burning and ejection of stellar material at a few percent of the speed of light. The spectacle we observe in the months that follow is from the leaking of radiation from this glowing mass of radioactive debris. The modeling of SN Ia light curves and spectra represents a complex problem in time-dependent radiative transfer. Here we discuss numerical methods, in particular Monte Carlo methods, for calculating 3D multi-wavelength radiative transport on massively parallel machines. Our approach involves a newly developed domain decomposition technique in which the memory load is distributed over multiple processors and photon packets are communicated from node to node. We present results for 2-dimensional models that explore white dwarf explosions over a range of explosion paradigms and ignition conditions. These models give insight into how variations in the initial conditions of the explosion affect the light curve we finally observe. We conclude with an outlook (and some initial results) for large scale 3D radiation transport calculations of SNe Ia in an era of petascale computing. C1 [Kasen, Daniel; Woosley, S. E.] Univ Calif Santa Cruz, Dept Phys & Astron, Santa Cruz, CA 95064 USA. [Kasen, Daniel] Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. [Thomas, R. C.] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Roepke, Fritz] Max Planck Inst Astrophys, Garching, Germany. RP Kasen, D (reprint author), Univ Calif Santa Cruz, Dept Phys & Astron, Santa Cruz, CA 95064 USA. EM kasen@ucolick.org OI Ropke, Friedrich/0000-0002-4460-0097 FU DOE SciDAC [DE FC02-0641438]; LLNL; ATLAS machine; ORNL through an INCITE award; NERSC FX Support for this work was provided by the DOE SciDAC Program under grant DE FC02-0641438. We are grateful for computer time provided by LLNL on the ATLAS machine, by ORNL through an INCITE award, and by NERSC NR 27 TC 12 Z9 12 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012007 DI 10.1088/1742-6596/125/1/012007 PG 16 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700008 ER PT S AU Kent, PRC AF Kent, P. R. C. BE Stevens, RL TI Computational challenges of large-scale, long-time, first-principles molecular dynamics SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID TOTAL-ENERGY CALCULATIONS; AUGMENTED-WAVE METHOD; PSEUDOPOTENTIALS; METALS AB Planerwave density functional calculations have traditionally been able to use the largest available supercomputing resources. We analyze the scalability of modern projector-augmented wave implementations to identify the challenges in performing molecular dynamics calculations of large systems containing many thousands of electrons. Benchmark calculations on the Cray XT4 demonstrate that global linear-algebra operations are the primary reason for limited parallel scalability. Plane-wave related operations can be made sufficiently scalable. Improving parallel linear-algebra performance is an essential step to reaching longer timescales in future large-scale molecular dynamics calculations. C1 Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37831 USA. RP Kent, PRC (reprint author), Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37831 USA. EM kentpr@ornl.gov RI Kent, Paul/A-6756-2008 OI Kent, Paul/0000-0001-5539-4017 NR 25 TC 12 Z9 12 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012058 DI 10.1088/1742-6596/125/1/012058 PG 12 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700059 ER PT S AU Li, XS AF Li, Xiaoye S. BE Stevens, RL TI Evaluation of SuperLU on multicore architectures SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The Chip Multiprocessor (CMP) will be the basic building block for computer systems ranging from laptops to supercomputers. New software developments at all levels are needed to fully utilize these systems. In this work, we evaluate performance of different high-performance sparse LU factorization and triangular solution algorithms on several representative multicore machines. We included both Pthreads and MPI implementations in this study and found that the Pthreads implementation consistently delivers good performance and that a left-looking algorithm is usually superior. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Li, XS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM xsli@lbl.gov NR 8 TC 5 Z9 5 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012079 DI 10.1088/1742-6596/125/1/012079 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700080 ER PT S AU Luo, XJ Shephard, M Lee, LQ Ng, C Ge, LX AF Luo, Xiaojuan Shephard, Mark Lee, Lie-Quan Ng, Cho Ge, Lixin BE Stevens, RL TI Curved mesh correction and adaptation tool to improve COMPASS electromagnetic analyses SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB SLAC performs large-scale simulations for the next-generation accelerator design using higher-order finite elements. This method requires using valid curved meshes and adaptive mesh refinement in complex 3D curved domains to achieve its fast rate of convergence. ITAPS has developed a procedure to address those mesh requirements to enable petascale electromagnetic accelerator simulations by SLAC. The results demonstrate that those correct valid curvilinear meshes can not only make the simulation more reliable but also improve computational efficiency up to 30%. C1 [Luo, Xiaojuan; Shephard, Mark] Rensselaer Polytech Inst, Troy, NY 12180 USA. [Lee, Lie-Quan; Ng, Cho; Ge, Lixin] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. RP Luo, XJ (reprint author), Rensselaer Polytech Inst, Troy, NY 12180 USA. EM xluo@scorec.rpi.edu; shephard@scorec.rpi.edu; liequan@slac.stanford.edu; cho@slac.stanford.edu; lge@slac.stanford.edu FU U.S. Department of Energy under DOE [DE-FC02-06ER25769, DE-AC02-76SF00515] FX This work is supported by U.S. Department of Energy under DOE grant number DE-FC02-06ER25769 and DE-AC02-76SF00515. NR 12 TC 1 Z9 1 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012082 DI 10.1088/1742-6596/125/1/012082 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700083 ER PT S AU Messer, OEB Bruenn, SW Blondin, JM Hix, WR Mezzacappa, A AF Messer, O. E. B. Bruenn, S. W. Blondin, J. M. Hix, W. R. Mezzacappa, A. BE Stevens, RL TI Multidimensional, multiphysics simulations of core-collapse supernovae SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID SPECTRAL NEUTRINO TRANSPORT; ROTATING MASSIVE STARS; 3 DIMENSIONS; DRIVEN CONVECTION; NUMERICAL-METHOD; ACCRETION SHOCK; MECHANISM; EXPLOSIONS; INSTABILITY; HYDRODYNAMICS AB CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We review the code's architecture and some recently improved implementations used in the code. We also briefly discuss preliminary results obtained with the code in three spatial dimensions. C1 [Messer, O. E. B.] Oak Ridge Natl Lab, Natl Ctr Computat Sci, Oak Ridge, TN 37831 USA. [Bruenn, S. W.] Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. [Blondin, J. M.] N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. [Hix, W. R.; Mezzacappa, A.] Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Messer, OEB (reprint author), Oak Ridge Natl Lab, Natl Ctr Computat Sci, Oak Ridge, TN 37831 USA. RI Hix, William/E-7896-2011; Messer, Bronson/G-1848-2012; Mezzacappa, Anthony/B-3163-2017 OI Hix, William/0000-0002-9481-9126; Messer, Bronson/0000-0002-5358-5415; Mezzacappa, Anthony/0000-0001-9816-9741 FU NSF PetaApps [OCI-0749242, OCI-0749248, OCI-0749204]; NASA [07 ATFP07-0011]; U. S. Department of Energy [DE-AC05-00OR22725]; Oak Ridge National Laboratory; ational Center for Computational Sciences at ORNL; National Energy Research Scientific Computing Center at LBNL; Texas Advanced Computing Center at the University of Texas FX This work was supported by the NSF PetaApps program under grant numbers OCI-0749242, OCI-0749248, and OCI-0749204, by NASA under grant 07 ATFP07-0011, and by the U. S. Department of Energy under Contract No. DE-AC05-00OR22725 at Oak Ridge National Laboratory. The simulations described here were performed at the National Center for Computational Sciences at ORNL, at the National Energy Research Scientific Computing Center at LBNL, and at the Texas Advanced Computing Center at the University of Texas. NR 52 TC 7 Z9 7 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012010 DI 10.1088/1742-6596/125/1/012010 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700011 ER PT S AU Moreland, K Lepage, D Koller, D Humphreys, G AF Moreland, Kenneth Lepage, Daniel Koller, David Humphreys, Greg BE Stevens, RL TI Remote rendering for ultrascale data SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The mission of the SciDAC Institute for Ultrascale Visualization is to address the upcoming petascale visualization challenges. As we move to petascale computation, we are seeing a trend not only in the growth but also in the consolidation of computing resources. As the distances between user and petascale visualization resources grow, the expected performance of the network degrades, especially with respect to latency. In this paper we will explore a technique for remote visualization that leverages unstructured lumigraph rendering. This technique will provide an interactive rendering experience regardless of the network performance to the remote visualization resource. The unstructured lumigraph rendering can also replace many of the other level-of-detail techniques currently used that have problems that are exasperated by petascale data. C1 [Moreland, Kenneth] Sandia Natl Labs, POB 5800 MS 1323, Albuquerque, NM 87185 USA. [Lepage, Daniel; Koller, David; Humphreys, Greg] Univ Virginia, Charlottesville, VA 22904 USA. RP Moreland, K (reprint author), Sandia Natl Labs, POB 5800 MS 1323, Albuquerque, NM 87185 USA. EM kmorel@sandia.gov FU United States Department of Energy's National Nuclear Security Administration [DE-AC04-94AL85000] FX This work was done in part at Sandia National Laboratories. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energys National Nuclear Security Administration under contract DE-AC04-94AL85000. NR 7 TC 2 Z9 2 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012096 DI 10.1088/1742-6596/125/1/012096 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700097 ER PT S AU Mundy, CJ Rousseau, R Curioni, A Kathmann, SM Schemer, GK AF Mundy, Christopher J. Rousseau, Roger Curioni, Alessandro Kathmann, Shawn M. Schemer, Gregory K. BE Stevens, RL TI A molecular approach to understanding complex systems: computational statistical mechanics using state-of-the-art algorithms on terascale computational platforms SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID CHEM.-CHEM.-PHYS.; LIQUID WATER; NEAT WATER; AQUEOUS-SOLUTION; 1ST PRINCIPLES; SURFACE; AUTOIONIZATION; EQUILIBRIA; INTERFACES; DYNAMICS AB We present our recent progress toward a molecular picture of reactions in complex fluids and at interfaces. In particular, we highlight the important statistical mechanical methodology as well as the electronic structure methods and algorithms that are used to tackle important unresolved questions in the chemical sciences. Moreover, we demonstrate that using the simulation protocol outlined, in conjunction with current and next generation computer hardware, a quantitative understanding of complex chemical problems in the condensed phase is within reach. C1 [Mundy, Christopher J.; Rousseau, Roger; Kathmann, Shawn M.; Schemer, Gregory K.] Pacific NW Natl Lab, Div Chem & Mat Sci, Richland, WA 99352 USA. [Curioni, Alessandro] IBM Corp, Zurich Res Lab, CH-8803 Ruschlikon, Switzerland. RP Mundy, CJ (reprint author), Pacific NW Natl Lab, Div Chem & Mat Sci, Richland, WA 99352 USA. EM chris.mundy@pnl.gov RI Rousseau, Roger/C-3703-2014 FU U.S. Department of Energy's (DOE) Office of Basic Energy Sciences Chemical Sciences program FX This work is supported by the U.S. Department of Energys (DOE) Office of Basic Energy Sciences Chemical Sciences program. Calculations are currently being performed at National Energy Research Scientific Computing Center (NERSC) on the Cray XT4 (Franklin) under the 2008 re-imbursement program, and through resources afforded by the 2008 INCITE award, namely the Cray XT4 (Jaguar) at Oak Ridge National Laboratory, the IBM Blue Gene/P (Intrepid) at Argonne National Laboratory. We also acknowledge the state-of-the-art facilities at PNNL, namely, the 1500 CPU Linux cluster comprised of 2.33 GHz Clovertown chips (NWice) . CJM acknowledges ongoing collaborations with Prof. Douglas Tobias (UC-Irvine), Dr. I. F. Will Kuo (LLNL), Dr. Liem Dang (PNNL), and Prof. Dr. J Hutter (U. Zurich). NR 25 TC 1 Z9 1 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012014 DI 10.1088/1742-6596/125/1/012014 PG 8 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700015 ER PT S AU Najm, HN Ray, J Safta, C Marzouk, Y Alorani, M Goussis, D AF Najm, H. N. Ray, J. Safta, C. Marzouk, Y. Alorani, M. Goussis, D. BE Stevens, RL TI High-order AMR computations of reacting flow with adaptive reduction of chemical stiffness SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID CHEMISTRY; KINETICS; ALGORITHM; SHOCK; CSP AB We outline a high-order adaptive mesh refinement construction for low Mach number reacting flow computations. We illustrate the order of accuracy on a model problem and demonstrate the construction for methane-air ignition in 2D channel flow. We also outline a nonparametric tabulation strategy for computational singular-perturbation time integration of a general chemical system. We demonstrate this adaptive chemistry technique for H-2-O-2 ignition. C1 [Najm, H. N.; Ray, J.; Safta, C.; Marzouk, Y.] Sandia Natl Labs, Livermore, CA 94550 USA. [Alorani, M.] Univ Rome, Rome, Italy. [Goussis, D.] Natl Tech Univ Athens, Athens, Greece. RP Najm, HN (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. EM hnnajm@sandia.gov OI VALORANI, Mauro/0000-0002-8260-6297 NR 17 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012032 DI 10.1088/1742-6596/125/1/012032 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700033 ER PT S AU Ng, C Akcelik, V Candel, A Chen, S Ge, LX Kabel, A Lee, LQ Li, ZH Prudencio, E Schussman, G Uplenchwar, R Xiao, LL Ko, K Austin, T Cary, JR Ovtchinnikov, S Smith, DN Werner, GR Bellantoni, L AF Ng, Cho Akcelik, Volkan Candel, Arno Chen, Sheng Ge, Lixin Kabel, Andreas Lee, Lie-Quan Li, Zenghai Prudencio, Ernesto Schussman, Greg Uplenchwar, Ravi Xiao, Liling Ko, Kwok Austin, T. Cary, J. R. Ovtchinnikov, S. Smith, D. N. Werner, G. R. Bellantoni, L. BE Stevens, RL TI Design and optimization of large accelerator systems through high-fidelity electromagnetic simulations SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB SciDAC-1, with its support for the "Advanced Computing for 21(st) Century Accelerator Science and Technology" project, witnessed dramatic advances in electromagnetic (EM) simulations for the design and optimization of important accelerators across the Office of Science. In SciDAC2, EM simulations continue to play an important role in the "Community Petascale Project for Accelerator Science and Simulation" (ComPASS), through close collaborations with SciDAC Centers and Insitutes in computational science. Existing codes will be improved and new multi-physics tools will be developed to model large accelerator systems with unprecedented realism and high accuracy using computing resources at petascale. These tools aim at targeting the most challenging problems facing the ComPASS project. Supported by advances in computational science research, they have been successfully applied to the International Linear Collider and the Large Hadron Collider in high energy physics, the JLab 12-GeV Upgrade in nuclear physics, and the Spallation Neutron Source and the Linac Coherent Light Source in basic energy sciences. C1 [Ng, Cho; Akcelik, Volkan; Candel, Arno; Chen, Sheng; Ge, Lixin; Kabel, Andreas; Lee, Lie-Quan; Li, Zenghai; Prudencio, Ernesto; Schussman, Greg; Uplenchwar, Ravi; Xiao, Liling; Ko, Kwok] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. [Austin, T.; Cary, J. R.; Ovtchinnikov, S.; Smith, D. N.; Werner, G. R.] TechX Corp, Boulder, CO 80303 USA. [Bellantoni, L.] Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ng, C (reprint author), Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. FU U.S. Department of Energy Office of High Energy Physics; Office of Basic Energy Sciences and Office of Advanced Scientific Computing Research [DEAC02-76SF00515, DE-FC02-07ER41499, DE-FG0204ER41317]; Oak Ridge National Laboratory and resources of the National Energy Research Scientific Computing Center; Office of Science of the Department of Energy [DE-AC05-00OR22725, DE-AC02- 05CH11231] FX We are grateful to H. Wang, F. Marhauser, J. Sekutowicz, C. Reece, and R. Rimmer of TJNAF for initiating the BBU problem in a CEBAF cryomodule and for supplying all the relevant measured data. This work was supported by the U.S. Department of Energy Office of High Energy Physics, Office of Basic Energy Sciences and Office of Advanced Scientific Computing Research under contract DEAC02-76SF00515 and grants DE-FC02-07ER41499 and DE-FG0204ER41317. This work used resources of the National Center for Computational Sciences at Oak Ridge National Laboratory and resources of the National Energy Research Scientific Computing Center, which are supported by the Office of Science of the Department of Energy under Contract DE-AC05-00OR22725 and DE-AC02- 05CH11231, respectively NR 17 TC 2 Z9 2 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012003 DI 10.1088/1742-6596/125/1/012003 PG 11 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700004 ER PT S AU Pascucci, V Mascarenhas, A AF Pascucci, Valerio Mascarenhas, Ajith BE Stevens, RL TI Multiscale Morse theory for science ciscovery SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID SURFACES AB Computational scientists employ increasingly powerful parallel supercomputers to model and simulate fundamental physical phenomena. These simulations typically produce massive amounts of data easily running into terabytes and petabytes in the near future. The future ability of scientists to analyze such data, validate their models, and understand the physics depends on the development of new mathematical frameworks and software tools that can tackle this unprecedented complexity in feature characterization and extraction problems. We present recent advances in Morse theory and its use in the development of robust data analysis tools. We demonstrate its practical use in the analysis of two large scale scientific simulations: (i) a direct numerical simulation and a large eddy simulation of the mixing layer in a hydrodynamic instability and (ii) an atomistic simulation of a porous medium under impact. Our ability to perform these two fundamentally different analyses using the same mathematical framework of Morse theory demonstrates the flexibility of our approach and its robustness in managing massive models. C1 [Pascucci, Valerio] Univ Utah, Sch Comp, Sci Comp & Imaging Inst, Salt Lake City, UT 84112 USA. [Mascarenhas, Ajith] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Pascucci, V (reprint author), Univ Utah, Sch Comp, Sci Comp & Imaging Inst, Salt Lake City, UT 84112 USA. EM pascucci@acm.org NR 19 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012098 DI 10.1088/1742-6596/125/1/012098 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700099 ER PT S AU Pordes, R Altunay, M Avery, P Bejan, A Blackburn, K Blatecky, A Gardner, R Kramer, B Livny, M Mcgee, J Potekhin, M Quick, R Olson, D Roy, A Sehgal, C Wenaus, T Wilde, M Wurthwein, F AF Pordes, Ruth Altunay, Mine Avery, Paul Bejan, Alina Blackburn, Kent Blatecky, Alan Gardner, Rob Kramer, Bill Livny, Miron McGee, John Potekhin, Maxim Quick, Rob Olson, Doug Roy, Alain Sehgal, Chander Wenaus, Torre Wilde, Mike Wuerthwein, Frank BE Stevens, RL TI New science on the Open Science Grid SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The Open Science Grid (OSG) includes work to enable new science, new scientists, and new modalities in support of computationally based research. There are frequently significant sociological and organizational changes required in transformation from the existing to the new. OSG leverages its deliverables to the large-scale physics experiment member communities to benefit new communities at all scales through activities in education, engagement, and the distributed facility. This paper gives both a brief general description and specific examples of new science enabled on the OSG. More information is available at the OSG web site: www.opensciencegrid.org. C1 [Pordes, Ruth; Altunay, Mine; Sehgal, Chander] Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. [Avery, Paul] Univ Florida, Gainesville, FL 32611 USA. [Bejan, Alina; Gardner, Rob; Wilde, Mike] Univ Chicago, Chicago, IL 60607 USA. [Blackburn, Kent] CALTECH, Pasadena, CA 91125 USA. [Blatecky, Alan; McGee, John] Renaissance Comp Inst, Chapel Hill, NC 27517 USA. [Kramer, Bill; Olson, Doug; Roy, Alain] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. [Livny, Miron] Univ Wisconsin, Madison, WI 53706 USA. [Quick, Rob; Wenaus, Torre] Indiana Univ, Bloomington, IN 47405 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. [Wuerthwein, Frank] Univ Calif San Diego, La Jolla, CA 92093 USA. RP Pordes, R (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM ruth@fnal.gov RI Bejan, Adrian/D-3909-2012 FU Office of Science, U.S. Department of Energy [DE-FC02-06ER41436]; National Science Foundation [PHY-0621704]; U.S. Department of Energy [DEAC02-76CH03000] FX This work was supported by the Office of Science, U.S. Department of Energy, SciDAC program under Contract DE-FC02-06ER41436 and the National Science Foundation Cooperative Agreement, PHY-0621704. Fermilab is supported by the U.S. Department of Energy under contract No. DEAC02-76CH03000. NR 8 TC 5 Z9 6 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012070 DI 10.1088/1742-6596/125/1/012070 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700071 ER PT S AU Qiang, J Borland, M Kabel, A Li, R Ryne, R Stern, E Wang, Y Wasserman, H Zhang, Y AF Qiang, J. Borland, M. Kabel, A. Li, R. Ryne, R. Stern, E. Wang, Y. Wasserman, H. Zhang, Y. BE Stevens, RL TI SciDAC advances in beam dynamics simulation: From light sources to colliders SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB In this paper, we report on progress that has been made in beam dynamics simulation, from light sources to colliders, during the first year of the SciDAC-2 accelerator project "Community Petascale Project for Accelerator Science and Simulation (ComPASS)." Several parallel computational tools for beam dynamics simulation are described. Also presented are number of applications in current and future accelerator facilities (e.g., LCLS, RHIC, Tevatron, LHC, and ELIC). C1 [Qiang, J.; Borland, M.; Ryne, R.; Wasserman, H.] Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Kabel, A.] Argonne Natl Lab, Argonne, IL 60439 USA. [Zhang, Y.] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. [Li, R.] Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. [Stern, E.] Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Qiang, J (reprint author), Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM jqiang@lbl.gov FU National Energy Research Scientific Computing Center (NERSC); U.S. Department of Energy [DE-AC02-05CH11231] FX This work used computing resources at the National Energy Research Scientific Computing Center (NERSC), supported by the U.S. Department of Energy under Contract no. DE-AC02-05CH11231 NR 6 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012004 DI 10.1088/1742-6596/125/1/012004 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700005 ER PT S AU Reynolds, DR Swesty, FD Woodward, CS AF Reynolds, Daniel R. Swesty, F. Douglas Woodward, Carol S. BE Stevens, RL TI A Newton-Krylov solver for implicit solution of hydrodynamics in core collapse supernovae SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID NONSYMMETRIC LINEAR-SYSTEMS; NEUTRINO BURST; ALGORITHM; EQUATION; STARS AB This paper describes an implicit approach and nonlinear solver for solution of radiation-hydrodynamic problems in the context of supernovae and proto-neutron star cooling. The robust approach applies Newton-Krylov methods and overcomes the difficulties of discontinuous limiters in the discretized equations and scaling of the equations over wide ranges of physical behavior. We discuss these difficulties, our approach for overcoming them, and numerical results demonstrating accuracy and efficiency of the method. C1 [Reynolds, Daniel R.] Univ Calif San Diego, Dept Math, La Jolla, CA 92093 USA. [Swesty, F. Douglas] SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. [Woodward, Carol S.] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Reynolds, DR (reprint author), Univ Calif San Diego, Dept Math, La Jolla, CA 92093 USA. EM drreynolds@ucsd.edu; dswesty@mail.astro.sunysb.edu; cswoodward@llnl.gov RI Woodward, Carol/M-4008-2014; OI Reynolds, Daniel/0000-0002-0911-7841 FU DOE Office of Science; U.S. Dept. of Energy, through the TOPS SciDAC project; Office of Science of the U.S. Dept. of Energy,through SciDAC [DE-FC02-01ER41185]; NERSC; NCCS; U.S. Department of Energy by Lawrence Livermore National Laboratory [DE-AC52-07NA27344] FX DRR and CSW gratefully acknowledge support by the DOE Office of Science of the U.S. Dept. of Energy, through the TOPS SciDAC project. FDS gratefully acknowledges support by the Office of Science of the U.S. Dept. of Energy, through SciDAC Award DE-FC02-01ER41185 and supercomputing support for this work at NERSC and NCCS. We also thank Eric Myra for many helpful discussions. The work of C S Woodward was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. NR 24 TC 3 Z9 3 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012085 DI 10.1088/1742-6596/125/1/012085 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700086 ER PT S AU Ross, RB Peterka, T Shen, HW Hong, Y Ma, KL Yu, H Moreland, K AF Ross, R. B. Peterka, T. Shen, H-W Hong, Y. Ma, K-L Yu, H. Moreland, K. BE Stevens, RL TI Visualization and parallel I/O at extreme scale SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB In our efforts to solve ever more challenging problems through computational techniques, the scale of our compute systems continues to grow. As we approach petascale, it becomes increasingly important that all the resources in the system be used as efficiently as possible, not just the floating-point units. Because of hardware, software, and usability challenges, storage resources are often one of the most poorly used and performing components of today's compute systems. This situation can be especially true in the case of the analysis phases of scientific workflows. In this paper we discuss the impact of large-scale data on visual analysis operations and examine a collection of approaches to I/O in the visual analysis process. First we examine the performance of volume rendering on a leadership-computing platform and assess the relative cost of I/O, rendering, and compositing operations. Next we analyze the performance implications of eliminating preprocessing from this example workflow. Then we describe a technique that uses data reorganization to improve access times for data-intensive volume rendering. C1 [Ross, R. B.; Peterka, T.] Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. [Shen, H-W; Hong, Y.] Ohio State Univ, Dept Comp Sci & Engn, Columbus, OH 43210 USA. [Ma, K-L; Yu, H.] Univ Calif Davis, Dept Comp Sci, Davis, CA 95616 USA. [Moreland, K.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ross, RB (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM rross@mcs.anl.gov FU Office of Advanced Scientific Computing Research; Office of Science, U.S.Department of Energy [DE-AC02-06CH11357]; NSF [CNS-0551727, CCF-0325934]; DOE [DE-FC02-06ER25777] FX This work was supported in part by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U.S.Department of Energy, under Contract DE-AC02-06CH11357. Work is also supported in part by NSF through grants CNS-0551727 and CCF-0325934, and DOE with agreement No. DE-FC02-06ER25777. NR 25 TC 5 Z9 6 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012099 DI 10.1088/1742-6596/125/1/012099 PG 10 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700100 ER PT S AU Samatova, NF Schmidt, MC Hendrix, W Breimyer, P Thomas, K Park, BH AF Samatova, N. F. Schmidt, M. C. Hendrix, W. Breimyer, P. Thomas, K. Park, B. -H. BE Stevens, RL TI Coupling graph perturbation theory with scalable parallel algorithms for large-scale enumeration of maximal cliques in biological graphs SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID ALIGNMENT; NETWORKS AB Data-driven construction of predictive models for biological systems faces challenges from data intensity, uncertainty, and computational complexity. Data-driven model inference is often considered a combinatorial graph problem where an enumeration of all feasible models is sought. The data-intensive and the NP-hard nature of such problems, however, challenges existing methods to meet the required scale of data size and uncertainty, even on modern supercomputers. Maximal clique enumeration (MCE) in a graph derived from such biological data is often a rate-limiting step in detecting protein complexes in protein interaction data, finding clusters of co-expressed genes in microarray data, or identifying clusters of orthologous genes in protein sequence data. We report two key advances that address this challenge. We designed and implemented the first (to the best of our knowledge) parallel NICE algorithm that scales linearly on thousands of processors running MCE on real-world biological networks with thousands and hundreds of thousands of vertices. In addition, we proposed and developed the Graph Perturbation Theory (GPT) that establishes a foundation for efficiently solving the MCE problem in perturbed graphs, which model the uncertainty in the data. GPT formulates necessary and sufficient conditions for detecting the differences between the sets of maximal cliques in the original and perturbed graphs and reduces the enumeration time by more than 80% compared to complete recomputation. C1 [Samatova, N. F.; Schmidt, M. C.; Hendrix, W.; Breimyer, P.] North Carolina State Univ, Dept Comp Sci, Raleigh, NC 27695 USA. [Samatova, N. F.; Schmidt, M. C.; Hendrix, W.; Breimyer, P.; Park, B. -H.] Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. [Thomas, K.] Cray Inc, Seattle, WA 98104 USA. RP Samatova, NF (reprint author), North Carolina State Univ, Dept Comp Sci, Raleigh, NC 27695 USA. EM samatovan@ornl.gov FU U.S. Department of Energy (Office of Advanced Scientific Computing Research, Office of Science); Oak Ridge National Laboratory; U.S. D.O.E [DEAC05-00OR22725] FX The authors are thankful to Cray Inc. for the access to large-scale Cray XT systems and the insights into the code optimization and benchmarks. This research has been supported by the Exploratory Data Intensive Computing for Complex Biological Systems project from U.S. Department of Energy (Office of Advanced Scientific Computing Research, Office of Science). The work of NFS was also sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory. Oak Ridge National Laboratory is managed by UT-Battelle for the LLC U.S. D.O.E. under contract no. DEAC05-00OR22725. NR 18 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012053 DI 10.1088/1742-6596/125/1/012053 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700054 ER PT S AU Samulyak, R Lu, TS Parks, P Glimm, J Li, XL AF Samulyak, Roman Lu, Tianshi Parks, Paul Glimm, James Li, Xiaolin BE Stevens, RL TI Simulation of pellet ablation for tokamak fueling with ITAPS front tracking SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID INJECTION; CLOUD AB A magnetohydrodynamic numerical model and parallel software for the ablation of cryogenic deuterium pellets in the process of tokamak fueling has been developed based on the method of front tracking of ITAPS Center. The main features of the model are the explicit tracking of material interfaces, a surface ablation model, a kinetic model for the electron heat flux, a cloud charging and rotation model, and an equation of state accounting for atomic processes in the ablation cloud. The software was used for the first systematic studies of the pellet ablation rate and properties of the ablation channel in magnetic fields. Simulations revealed new features of the pellet ablation such as strong dependence of the radius of the ablation channel and ablation rate on the "warm-up" time and supersonic spinning of the ablation channel. C1 [Samulyak, Roman; Glimm, James; Li, Xiaolin] SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. [Samulyak, Roman; Lu, Tianshi; Glimm, James] Brookhaven Natl Lab, Computat Sci Ctr, Upton, NY 11973 USA. [Parks, Paul] Gen Atom Co, San Diego, CA 92186 USA. RP Samulyak, R (reprint author), SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. EM rosamu@ams.sunysb.edu FU U.S. Department of Energy [DE-AC02-98CH10886]; State of New York FX This research utilized resources at the New York Center for Computational Sciences at Stony Brook University/Brookhaven National Laboratory which is supported by the U.S. Department of Energy under Contract No. DE-AC02-98CH10886 and by the State of New York. NR 8 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012081 DI 10.1088/1742-6596/125/1/012081 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700082 ER PT S AU Scheibe, TD Tartakovsky, AM Tartakovsky, DM Redden, GD Meakin, P Palmer, BJ Schuchardt, KL AF Scheibe, T. D. Tartakovsky, A. M. Tartakovsky, D. M. Redden, G. D. Meakin, P. Palmer, B. J. Schuchardt, K. L. BE Stevens, RL TI Hybrid numerical methods for multiscale simulations of subsurface biogeochemical processes SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID SMOOTHED PARTICLE HYDRODYNAMICS; CONTINUUM; MODELS; FLOW AB Many subsurface flow and transport problems of importance today involve coupled non-linear processes that occur in media exhibiting complex heterogeneity. Problems involving biological mediation of reactions fall into this class of problems. Recent experimental research has revealed important details about the physical, chemical, and biological mechanisms that control these processes from the molecular to laboratory scales. We are developing a hybrid multiscale modeling framework that combines discrete pore-scale models (which explicitly represent the pore space geometry at a local scale) with continuum field-scale models (which conceptualize flow and transport in a porous medium without a detailed representation of the pore space geometry). At the pore scale, we have implemented a parallel three-dimensional Lagrangian model of flow and transport using the smoothed particle hydrodynamics method and performed test simulations using millions of computational particles on the supercomputer at the Environmental Molecular Sciences Laboratory. We have also developed methods for gridding arbitrarily complex pore geometries and simulating pore-scale flow and transport using parallel implementations of grid-based computational fluid dynamics methods. Within the multiscale hybrid framework, we have coupled pore- and continuum-scale models to simulate coupled diffusive mixing, reaction, and mineral precipitation, and compared the results with conventional continuum-only simulations. The hybrid multiscale modeling framework is being developed using a number of SciDAC enabling technologies including the Common Component Architecture, advanced solvers, Grid technologies, scientific workflow tools, and visualization technologies. C1 [Scheibe, T. D.; Tartakovsky, A. M.; Palmer, B. J.; Schuchardt, K. L.] Pacific Northwest Natl Lab, Richland, WA 99352 USA. [Tartakovsky, D. M.] Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. [Redden, G. D.; Meakin, P.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. [Meakin, P.] Univ Oslo, Phys Geol Proc, Oslo, Norway. RP Scheibe, TD (reprint author), Pacific Northwest Natl Lab, Richland, WA 99352 USA. EM tim.scheibe@pnl.gov RI Scheibe, Timothy/A-8788-2008 OI Scheibe, Timothy/0000-0002-8864-5772 NR 15 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012054 DI 10.1088/1742-6596/125/1/012054 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700055 ER PT S AU Sisneros, R Glatter, M Langley, B Huang, J Hoffman, F Erickson, DJ AF Sisneros, Robert Glatter, Markus Langley, Brandon Huang, Jian Hoffman, Forrest Erickson, David J., III BE Stevens, RL TI Time-varying multivariate visualization for understanding terrestrial biogeochemistry SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB Petascale computing has brought forth a transformational way of doing science. To the global effort on studying climate change, this shift has enabled not only tools more functional and more powerful than before but also a scientific exploration more comprehensive than before. In this work, we report our efforts to employ recent ultrascale visualization technologies (SciDAC Ultravis) to study model comparison in terrestrial biogeochemistry datasets produced by computation (SciDAC GLAMP). While many of the current efforts are specific to climate modeling research, our method of location-specific summarizing visualization of extreme and normal relative distribution patterns is generally applicable to other fields of computational sciences. C1 [Sisneros, Robert; Glatter, Markus; Langley, Brandon; Huang, Jian] Univ Tennessee, Knoxville, TN 37996 USA. [Hoffman, Forrest; Erickson, David J., III] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Sisneros, R (reprint author), Univ Tennessee, Knoxville, TN 37996 USA. EM sisneros@cs.utk.edu; glatter@cs.utk.edu; langley@cs.utk.edu; huangj@cs.utk.edu; hoffmanfm@ornl.gov; ericksondj@ornl.gov RI Hoffman, Forrest/B-8667-2012 OI Hoffman, Forrest/0000-0001-5802-4134 FU Institute of Ultra-Scale Visualization; SciDAC; NSF [CNS-0437508]; DOE Early Career PI [DE-FG02-04ER25610]; Climate Change Research Division (CCRD); DOE [DE-AC05-00OR22725] FX The primary source of funding for this work is provided through Institute of Ultra-Scale Visualization (www.ultravis.org) under the auspices of the SciDAC program within the U.S. Department of Energy (DOE). This work is also supported in part by NSF grant CNS-0437508 and a DOE Early Career PI grant awarded to Jian Huang (No. DE-FG02-04ER25610). The Carbon-Land Model Intercomparison Project (C-LAMP) are partially sponsored by the Climate Change Research Division (CCRD) of the Office of Biological and Environmental Research (OBER) and the Computational Science Research and Partnerships (SciDAC) Division of the Office of Advanced Scientific Computing Research (OASCR) within DOE Office of Science. This research used resources of the National Center for Computational Science (NCCS) at Oak Ridge National Laboratory (ORNL), which is managed by UT-Battelle, LLC, for DOE under Contract No. DE-AC05-00OR22725. NR 9 TC 1 Z9 1 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012093 DI 10.1088/1742-6596/125/1/012093 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700094 ER PT S AU Spentzouris, P Cary, J McInnes, LC Mori, W Ng, C Ng, E Ryne, R AF Spentzouris, Panagiotis Cary, John McInnes, Lois Curfman Mori, Warren Ng, Cho Ng, Esmond Ryne, Robert BE Stevens, RL TI Community petascale project for accelerator science and simulation: Advancing computational science for future accelerators and accelerator technologies SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID BEAMS AB The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessary accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors. C1 [Spentzouris, Panagiotis] Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. [Cary, John] Tech X Corp, Boulder, CO 80303 USA. [McInnes, Lois Curfman] Argonne Natl Lab, Argonne, IL 60439 USA. [Mori, Warren] Univ California, Los Angeles, CA 90024 USA. [Ng, Cho] Stanford Linear Accelerator Ctr, Stanford, CA USA. [Ng, Esmond; Ryne, Robert] Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Spentzouris, P (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM spentz@fnal.gov FU SciDAC program by the U.S. Department of Energy Office of High Energy Physics; Office of Nuclear Physics; Office of Basic Energy Sciences; Office of Advanced Scientific Computing Research; National Energy Research Scientific Computing Center and the Fermilab Lattice QCD facility FX The ComPASS project is supported under the SciDAC program by the U.S. Department of Energy Office of High Energy Physics, Office of Nuclear Physics, Office of Basic Energy Sciences, and Office of Advanced Scientific Computing Research. The simulation work presented here used resources of the National Energy Research Scientific Computing Center and the Fermilab Lattice QCD facility. NR 22 TC 1 Z9 1 U1 0 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012005 DI 10.1088/1742-6596/125/1/012005 PG 15 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700006 ER PT S AU Townsley, DM Bair, RA Dubey, A Fisher, RT Hearn, NC Lamb, DQ Riley, KM AF Townsley, Dean M. Bair, Raymond A. Dubey, Anshu Fisher, Robert T. Hearn, Nathan C. Lamb, Don Q. Riley, Katherine M. BE Stevens, RL TI Large-scale simulations of buoyancy-driven turbulent nuclear burning SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID 3-DIMENSIONAL NUMERICAL SIMULATIONS; FLUID DYNAMICAL SIMULATIONS; RAYLEIGH-TAYLOR INSTABILITY; IA-SUPERNOVAE; DEFLAGRATION PHASE; MODEL; FLAMES; DETONATION; EVOLUTION; ASTROPHYSICS AB An critical uncertainty in modeling thermonuclear supernovae is the degree of enhancement of the burning rate by turbulence during the subsonic burning (deflagration) phase. As turbulent combustion in the laboratory is still an active area of research, this remains a challenging problem. A unique feature of turbulent combustion in supernovae is that the driving of the turbulence arises from the strong buoyancy of the burned material. We discuss the large-scale fully three dimensional studies under way. These studies have the goals of characterizing the essential length scales of flame surface structure and thereby developing specific requirements that models of small-scale structure must meet. We discuss some preliminary results of our study concerning the scale-dependence of flame surface structure. C1 [Townsley, Dean M.; Dubey, Anshu; Fisher, Robert T.; Hearn, Nathan C.; Lamb, Don Q.] Univ Chicago, Ctr Astrophys Thermonucl Flashes, Chicago, IL 60637 USA. [Townsley, Dean M.] Univ Chicago, Joint Inst Nucl Astrophys, Chicago, IL 60637 USA. [Bair, Raymond A.; Riley, Katherine M.] Argonne Natl Lab, Argonne Leadership Comp Facil, Argonne, IL 60439 USA. RP Townsley, DM (reprint author), Univ Chicago, Ctr Astrophys Thermonucl Flashes, Chicago, IL 60637 USA. EM townsley@uchicago.edu NR 24 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012009 DI 10.1088/1742-6596/125/1/012009 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700010 ER PT S AU Trebotich, D Van Straalen, B Graves, D Colella, P AF Trebotich, David Van Straalen, Brian Graves, Dan Colella, Phil BE Stevens, RL TI Performance of Embedded Boundary Methods for CFD with Complex Geometry SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB In this paper, we discuss some of the issues in obtaining high performance for block-structured adaptive mesh refinement software for partial differential equations in complex geometry using embedded boundary/volume-of-fluid methods. We present the design of all adaptive embedded boundary multigrid algorithm for elliptic problems. We show examples in which this new elliptic solver scales to 1000 processors. We also apply this technology to more complex mathematical and physical algorithms for incompressible fluid dynamics and demonstrate similar scaling. C1 [Trebotich, David] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. [Van Straalen, Brian; Graves, Dan; Colella, Phil] Lawrence Livermore Natl Lab, Appl Numer Algorithms Grp, Berkeley, CA 94720 USA. RP Trebotich, D (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. EM trebotich@llnl.gov NR 10 TC 6 Z9 7 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012083 DI 10.1088/1742-6596/125/1/012083 PG 6 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700084 ER PT S AU Vashishta, P Kalia, RK Nakano, A Kaxiras, E Grama, A Lu, G Eidenbenz, S Voter, AF Hood, RQ Moriarty, JA Yang, LH AF Vashishta, Priya Kalia, Rajiv K. Nakano, Aiichiro Kaxiras, Efthimios Grama, Ananth Lu, Gang Eidenbenz, Stephan Voter, Arthur F. Hood, Randy Q. Moriarty, John A. Yang, Lin H. BE Stevens, RL TI Hierarchical petascale simulation framework for stress corrosion cracking SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID TRANSITION-METALS AB We are developing a scalable parallel and distributed computational framework consisting of methods, algorithms, and integrated software tools for multi-terascle-to-petascale simulations of stress corrosion cracking (SCC) with quantum-level accuracy. We have performed multimillion- to billion-atom molecular dynamics (MD) simulations of deformation, flow, and fracture in amorphous silica with interatomic potentials and forces validated by density functional theory (DFT) calculations. Optimized potentials have been developed to study sulfur embrittlement of nickel with multimillion-to-multibillion atom MD simulations based on DFT and temperature dependent model generalized pseudopotential theory. We have also developed a quasi-continuum method embedded with quantum simulations based on DFT to reach macroscopic length scales and an accelerated molecular dynamics scheme to reach macroscopic time scales in simulations of solid-fluid interfaces that are relevant to SCC. A hybrid MD and mesoscale lattice Boltzmann simulation algorithm is being designed to study fluid flow through cracks. C1 [Vashishta, Priya; Kalia, Rajiv K.; Nakano, Aiichiro] Univ So Calif, Los Angeles, CA 90089 USA. [Kaxiras, Efthimios] Harvard Univ, Cambridge, MA 02138 USA. [Grama, Ananth] Purdue Univ, W Lafayette, IN 47907 USA. [Lu, Gang] Calif State Univ Northridge, Northridge, CA 91330 USA. [Eidenbenz, Stephan; Voter, Arthur F.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Hood, Randy Q.; Moriarty, John A.; Yang, Lin H.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Vashishta, P (reprint author), Univ So Calif, Los Angeles, CA 90089 USA. EM priyav@usc.edu OI Eidenbenz, Stephan/0000-0002-2628-1854; Voter, Arthur/0000-0001-9788-7194 NR 12 TC 0 Z9 0 U1 1 U2 9 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012060 DI 10.1088/1742-6596/125/1/012060 PG 18 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700061 ER PT S AU Williams, DN Ananthakrishnan, R Bernholdt, DE Bharathi, S Brown, D Chen, M Chervenak, AL Cinquini, L Drach, R Foster, IT Fox, P Hankin, S Henson, VE Jones, P Middleton, DE Schwidder, J Schweitzer, R Schuler, R Shoshani, A Siebenlist, F Sim, A Strand, WG Wilhelmi, N Su, M AF Williams, D. N. Ananthakrishnan, R. Bernholdt, D. E. Bharathi, S. Brown, D. Chen, M. Chervenak, A. L. Cinquini, L. Drach, R. Foster, I. T. Fox, P. Hankin, S. Henson, V. E. Jones, P. Middleton, D. E. Schwidder, J. Schweitzer, R. Schuler, R. Shoshani, A. Siebenlist, F. Sim, A. Strand, W. G. Wilhelmi, N. Su, M. BE Stevens, RL TI Data management and analysis for the Earth System Grid SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB The international climate community is expected to generate hundreds of petabytes of simulation data within the next five to seven years. This data must be accessed and analyzed by thousands of analysts worldwide in order to provide accurate and timely estimates of the likely impact of climate change on physical, biological, and human systems. Climate change is thus not only a scientific challenge of the first order but also a major technological challenge. In order to address this technological challenge, the Earth System Grid Center for Enabling Technologies (ESG-CET) has been established within the U.S. Department of Energy's Scientific Discovery through Advanced Computing (SciDAC)-2 program, with support from the offices of Advanced Scientific Computing Research and Biological and Environmental Research. ESG-CET's mission is to provide climate researchers worldwide with access to the data, information, models, analysis tools, and computational capabilities required to make sense of enormous climate simulation datasets. Its specific goals are to (1) make data more useful to climate researchers by developing Grid technology that enhances data usability; (2) meet specific distributed database, data access, and data movement needs of national and international climate projects; (3) provide a universal and secure web-based data access portal for broad multi-model data collections; and (4) provide a wide-range of Grid-enabled climate data analysis tools and diagnostic methods to international climate centers and U.S. government agencies. Building on the successes of the previous Earth System Grid (ESG) project, which has enabled thousands of researchers to access tens of terabytes of data from a small number of ESG sites, ESG-CET is working to integrate a far larger number of distributed data providers, high-bandwidth wide-area networks, and remote computers in a highly collaborative problem-solving environment. C1 [Williams, D. N.; Drach, R.; Henson, V. E.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Ananthakrishnan, R.; Siebenlist, F.] Argonne Natl Lab, Chicago, IL USA. [Shoshani, A.; Sim, A.] Lawrence Berkeley Natl Lab, Berkeley, CA USA. [Jones, P.] Los Alamos Natl Lab, Los Alamos, NM USA. [Brown, D.; Cinquini, L.; Fox, P.; Middleton, D. E.; Strand, W. G.; Wilhelmi, N.] Natl Ctr Atmospher Res, Boulder, CO USA. [Hankin, S.; Schweitzer, R.] Natl Ocean & Atmospher Adm PMEL, Seattle, WA USA. [Bernholdt, D. E.; Chen, M.; Schwidder, J.] Oak Ridge Natl Lab, Oak Ridge, TN USA. [Bharathi, S.; Chervenak, A. L.; Schuler, R.; Su, M.] Univ So Calif, Inst Sci Informat, Marina Del Rey, CA USA. RP Williams, DN (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM williams13@llnl.gov; bernholdtde@ornl.gov; itf@mcs.anl.gov OI Strand, Warren/0000-0001-9740-0104; Fox, Peter/0000-0002-1009-7163 FU U.S. Department of Energy Office of Science, Offices of Advanced Scientific Computing Research and Biological and Environmental Research [DEAC02-05CH11231, W-7405-Eng-48, DE-AC52-06NA25396, DE-AC-05-00OR22725]; Argonne Chicago LLC [DE-AC02-06CH11357]; University of Southern California; National Science Foundation FX This work is supported through the U.S. Department of Energy Office of Science, Offices of Advanced Scientific Computing Research and Biological and Environmental Research, through the SciDAC program. Argonne National Laboratory is managed by Argonne Chicago LLC under Contract DE-AC02-06CH11357. Information Sciences Institute is a research institute of the Viterbi School of Engineering at the University of Southern California. Lawrence Berkeley National Laboratory is managed by the University of California for the U.S. Department of Energy under contract No. DEAC02-05CH11231. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy under contract No. W-7405-Eng-48. Los Alamos National Security is managed by LLC (LANS) for the U.S. Department of Energy under the contract No. DE-AC52-06NA25396. National Center for Atmospheric Research is managed by the University Corporation for Atmospheric Research under the sponsorship of the National Science Foundation. Oak Ridge National Laboratory is managed by UT-Battelle, LLC for the U.S. Dept. of Energy under contract DE-AC-05-00OR22725. Pacific Marine Environmental Laboratory is under the National Oceanic and Atmospheric Administration's line office of Ocean and Atmosphere Research, lies within the U.S. Department of Commerce. NR 15 TC 7 Z9 7 U1 2 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012072 DI 10.1088/1742-6596/125/1/012072 PG 15 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700073 ER PT S AU Williams, S Datta, K Carter, J Oliker, L Shalf, J Yelick, K Bailey, D AF Williams, Samuel Datta, Kaushik Carter, Jonathan Oliker, Leonid Shalf, John Yelick, Katherine Bailey, David BE Stevens, RL TI PERI - Auto-tuning memory-Intensive kernels for multicore SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex AB We present an auto-tuning approach to optimize application performance on emerging multicore architectures. The methodology extends the idea of search-based performance optimizations, popular in linear algebra and FFT libraries, to application-specific computational kernels. Our work applies this strategy to sparse matrix vector multiplication (SpMV), the explicit heat equation PDE on a regular grid (Stencil), and a lattice Boltzmann application (LBMHD). We explore one of the broadest sets of multicore architectures in the high-performance computing literature, including the Intel Xeon Clovertown, AMD Opteron Barcelona, Sun Victoria Falls, and the Sony-Toshiba-IBM (STI) Cell. Rather than hand-tuning each kernel for each system, we develop a code generator for each kernel that allows us identify a highly optimized version for each platform, while amortizing the human programming effort. Results show that our auto-tuned kernel applications often achieve a better than 4 x improvement compared with the original code. Additionally, we analyze a Roofline performance model for each platform to reveal hardware bottlenecks and software challenges for future multicore systems and applications. C1 [Williams, Samuel; Carter, Jonathan; Oliker, Leonid; Shalf, John; Yelick, Katherine; Bailey, David] Univ Calif Berkeley, Lawrence Berkeley Lab, CRD NERSC, Berkeley, CA 94720 USA. [Williams, Samuel; Datta, Kaushik; Oliker, Leonid; Yelick, Katherine] Univ Calif Berkeley, Div Comp Sci, Berkeley, CA 94720 USA. RP Williams, S (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, CRD NERSC, Berkeley, CA 94720 USA. EM SWWilliams@lbl.gov; kdatta@eecs.berkeley.edu; JTCarter@lbl.gov; LOliker@lbl.gov; JShalf@lbl.gov; KAYelick@lbl.gov; DHBailey@lbl.gov FU U.S. Dept. of Energy [DE-AC02-06CH11357.] FX This work was supported in part by the U.S. Dept. of Energy under Contract DE-AC02-06CH11357. NR 17 TC 2 Z9 2 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012038 DI 10.1088/1742-6596/125/1/012038 PG 15 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700039 ER PT S AU Zingale, M Almgren, AS Bell, JB Malone, CM Nonaka, A AF Zingale, M. Almgren, A. S. Bell, J. B. Malone, C. M. Nonaka, A. BE Stevens, RL TI Astrophysical applications of the MAESTRO code SO SCIDAC 2008: SCIENTIFIC DISCOVERY THROUGH ADVANCED COMPUTING SE Journal of Physics Conference Series LA English DT Proceedings Paper CT 4th Annual Scientific Discovery Through Advanced Computing Conference (SciDAC 2008) CY JUL 13-17, 2008 CL Seattle, WA SP US DOE Off Sci, Cray, IBM, Intel, HP, SiCortex ID X-RAY-BURSTS; IA SUPERNOVA EXPLOSION; NEUTRON-STARS; THERMONUCLEAR RUNAWAYS; CARBON IGNITION; MODEL; DETONATION; ENERGY AB Convective velocities in a white dwarf leading up to a Type la supernova or in the accreted layers on a neutron star preceding an X-ray burst are very subsonic. Under these conditions, sound waves can be neglected, but capturing compressibility effects due to nuclear reactions and background stratification is critical to accurately model the flow. We have developed a new algorithm, MAESTRO, based on a low Mach number formulation that exploits the separation of scales between the fluid velocity and the speed of sound. Here, we provide a brief overview of MAESTRO and present the initial astrophysical applications of the algorithm. C1 [Zingale, M.; Malone, C. M.] SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. [Almgren, A. S.; Bell, J. B.; Nonaka, A.] Lawrence Berkeley Natl Lab, Ctr Comp Sci & Engn, Berkeley, CA 94720 USA. RP Zingale, M (reprint author), SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. EM mzingale@mail.astro.sunysb.edu OI Zingale, Michael/0000-0001-8401-030X FU SciDAC Program of the DOE Office of Mathematics, Information, and Computational Sciences under the U.S. Department of Energy [DE-AC02-05CH11231]; DOE/Office of Nuclear Physics [DE-FG02-06ER41448]; Office of Science of the U.S. Department of Energy [DE-AC02-05CH11231, DE AC05 00OR22725]; National Energy Research Scientific Computing Center FX We thank Stan Woosley for providing the initial model for the convecting WD and many helpful conversations about ignition physics, and Andrew Cumming for providing the initial model for the XRB. We also thank Frank Timmes for providing his equation of state and conductivity routines online. This work was supported by the SciDAC Program of the DOE Office of Mathematics, Information, and Computational Sciences under the U.S. Department of Energy under contract No. DE-AC02-05CH11231 and by a DOE/Office of Nuclear Physics Outstanding Junior Investigator award, grant No. DE-FG02-06ER41448, to Stony Brook. Computer time for this project was provided through a DOE INCITE at the National Center for Computational Sciences at Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE AC05 00OR22725, on Livermore Computings Atlas machine through LLNLs Multiprogrammatic & Institutional Computing Program, and at the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. NR 23 TC 2 Z9 2 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1742-6588 J9 J PHYS CONF SER PY 2008 VL 125 AR 012013 DI 10.1088/1742-6596/125/1/012013 PG 5 WC Computer Science, Theory & Methods; Mathematics, Applied; Physics, Applied SC Computer Science; Mathematics; Physics GA BIK28 UT WOS:000260370700014 ER PT J AU Sims, BH AF Sims, Benjamin Hayden TI The uclear borderlands: The Manhattan project in post-cold war New Mexico SO SCIENCE TECHNOLOGY & HUMAN VALUES LA English DT Book Review C1 [Sims, Benjamin Hayden] Los Alamos Natl Lab, Stat Sci Grp, Los Alamos, NM 87545 USA. RP Sims, BH (reprint author), Los Alamos Natl Lab, Stat Sci Grp, Los Alamos, NM 87545 USA. NR 8 TC 0 Z9 0 U1 1 U2 2 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0162-2439 J9 SCI TECHNOL HUM VAL JI Sci. Technol. Hum. Values PD JAN PY 2008 VL 33 IS 1 BP 137 EP 142 DI 10.1177/0895904805303205 PG 6 WC Social Issues SC Social Issues GA 245NB UT WOS:000251940900007 ER PT S AU Brunetti, G Blasi, P Cassano, R Gabici, S AF Brunetti, G. Blasi, P. Cassano, R. Gabici, S. BE Bastieri, D Rando, R TI High energy emission from galaxy clusters and particle acceleration due to MHD turbulence SO SCIENCE WITH THE NEW GENERATION OF HIGH ENERGY GAMMA-RAY EXPERIMENTS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th Workshop on High Energy Gamma-Ray Experiments CY OCT 08-10, 2008 CL Abano Terme, ITALY SP Univ Padua, Natl Inst Nucl Phys, Sect Padua DE Particle acceleration; Turbulence; Galaxy clusters; Gamma rays ID LARGE-SCALE STRUCTURE; COSMIC-RAY ELECTRONS; GAMMA-RAY; RADIO HALOS; ALFVENIC REACCELERATION; RELATIVISTIC-PARTICLES; SHOCK-WAVES; STATISTICS; PROTONS; ORIGIN AB In the next years the FERMI gamma ray telescope and the Cherenkov telescopes will put very stringent constraints to models of gamma ray emission from galaxy clusters providing crucial information on relativistic particles in the inter-galactic-medium. We derive the broad band non-thermal spectrum of galaxy clusters in the context of general calculations in which relativistic particles (protons and secondary electrons due to proton-proton collisions) interact with MHD turbulence generated in the cluster volume during cluster mergers, and discuss the importance of future gamma ray observations. C1 [Brunetti, G.; Cassano, R.] Ist Radioastron, INAF, Via P Gobetti 101, I-40129 Bologna, Italy. [Blasi, P.] INAF Osserv Astrofisico diArcetri, Italy & Theoret Astrophys, Fermi Natl Accelerator Lab, Batavia, IL USA. [Gabici, S.] Dublin Inst Adv Studies, Dublin, Ireland. RP Brunetti, G (reprint author), Ist Radioastron, INAF, Via P Gobetti 101, I-40129 Bologna, Italy. FU ASI-INAF [1/088/06/0, PRIN-INAF2007] FX We acknowledge partial support from ASI-INAF 1/088/06/0 and PRIN-INAF2007. NR 40 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0649-0 J9 AIP CONF PROC PY 2008 VL 1112 BP 129 EP + PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BJK68 UT WOS:000266714100016 ER PT J AU Zweibel, K Mason, J Fthenakis, V AF Zweibel, Ken Mason, James Fthenakis, Vasilis TI By 2050 solar power could end US dependence on foreign oil and slash greenhouse gas emissions SO SCIENTIFIC AMERICAN LA English DT Article AB Slash greenhouse gases and foreign fuel has been the source of energy in United States so far. Now, solar energy could become the next source of energy, according to researchers. A massive switch from coal, oil, natural gas and nuclear power to solar power could supply 69% of US.'s electricity and 35% of its total energy by the year 2050. Large solar concentrator power plants would be built as well. C1 [Zweibel, Ken] Prime Star Solar, Golden, CO USA. [Mason, James] Solar Energy Campaign, Farmingdale, NY USA. [Mason, James] Hydrogen Res Inst, Farmingdale, NY USA. [Fthenakis, Vasilis] Brookhaven Natl Lab, Photovolta Environm Res Ctr, Upton, NY 11973 USA. [Fthenakis, Vasilis] Columbia Univ, Ctr Life Cycle Anal, New York, NY 10027 USA. RP Zweibel, K (reprint author), Prime Star Solar, Golden, CO USA. NR 2 TC 57 Z9 60 U1 2 U2 16 PU SCI AMERICAN INC PI NEW YORK PA 415 MADISON AVE, NEW YORK, NY 10017 USA SN 0036-8733 J9 SCI AM JI Sci.Am. PD JAN PY 2008 VL 298 IS 1 BP 64 EP + PG 9 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 248GN UT WOS:000252140800050 PM 18225697 ER PT S AU Wu, KS Stockinger, K Shoshani, A AF Wu, Kesheng Stockinger, Kurt Shoshani, Arie BE Ludascher, B Mamoulis, N TI Breaking the curse of cardinality on bitmap indexes SO SCIENTIFIC AND STATISTICAL DATABASE MANAGEMENT, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 20th International Conference on Scientific and Statistical Database Management CY JUL 09-11, 2008 CL Hong Kong, PEOPLES R CHINA AB Bitmap indexes are known to be efficient for ad-hoe range queries that are common in data warehousing and scientific applications. However, they suffer from the curse of cardinality, that is, their efficiency deteriorates as attribute cardinalities increase. A number of strategies have been proposed, but none of them addresses the problem adequately. In this paper, we propose a novel binned bitmap index that greatly reduces the cost to answer queries, and therefore breaks the curse of cardinality. The key idea is to augment the binned index with an Order-preserving Bin-based Clustering (OrBiC) structure. This data structure significantly reduces the I/O operations needed to resolve records that can not be resolved with the bitmaps. To further improve the proposed index structure, we also present a strategy to create single-valued bins for frequent values. This strategy reduces index sizes and improves query processing speed. Overall, the binned indexes with OrBiC great improves the query processing speed, and are 3 - 25 times faster than the best available indexes for high-cardinality data. C1 [Wu, Kesheng; Stockinger, Kurt; Shoshani, Arie] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Wu, KS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 26 TC 16 Z9 16 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-69476-2 J9 LECT NOTES COMPUT SC PY 2008 VL 5069 BP 348 EP 365 PG 18 WC Computer Science, Information Systems; Computer Science, Theory & Methods SC Computer Science GA BIA98 UT WOS:000258024500021 ER PT S AU Ngu, AHH Bowers, S Haasch, N McPhillips, T Critchlow, T AF Ngu, Anne H. H. Bowers, Shawn Haasch, Nicholas McPhillips, Timothy Critchlow, Terence BE Ludascher, B Mamoulis, N TI Flexible scientific workflow modeling using frames, templates, and dynamic embedding SO SCIENTIFIC AND STATISTICAL DATABASE MANAGEMENT, PROCEEDINGS SE Lecture Notes in Computer Science LA English DT Proceedings Paper CT 20th International Conference on Scientific and Statistical Database Management CY JUL 09-11, 2008 CL Hong Kong, PEOPLES R CHINA AB While most scientific workflows systems are based on dataflow, some amount of control-flow modeling is often necessary for engineering fault-tolerant, robust, and adaptive workflows. However, control-flow modeling within dataflow often results in workflow specifications that are hard to comprehend, reuse, and maintain. We describe new modeling constructs to address these issues that provide a structured approach for modeling control-flow within scientific workflows, and discuss their implementation within the Kepler scientific workflow system. C1 [Ngu, Anne H. H.; Haasch, Nicholas] Texas State Univ, San Marcos, TX 78666 USA. [Bowers, Shawn; McPhillips, Timothy] Univ Calif Davis, Genome Ctr, Davis, CA USA. [Critchlow, Terence] Pacific Northwest Natl Lab, Richland, WA USA. RP Ngu, AHH (reprint author), Texas State Univ, San Marcos, TX 78666 USA. FU NSF [DBI-0533368, IIS-0612326, IIS-0630033, OCI-0722079] FX This work supported in part through NSF grants DBI-0533368, IIS-0612326, IIS-0630033, and OCI-0722079. NR 16 TC 9 Z9 9 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-69476-2 J9 LECT NOTES COMPUT SC PY 2008 VL 5069 BP 566 EP + PG 3 WC Computer Science, Information Systems; Computer Science, Theory & Methods SC Computer Science GA BIA98 UT WOS:000258024500037 ER PT S AU Jantzen, CM Marra, JC AF Jantzen, Carol M. Marra, James C. BE Lee, WE Roberts, JW Hyatt, NC Grimes, RW TI High level waste (HLW) vitrification experience in the US: Application of glass product/process control to other HLW and hazardous wastes SO SCIENTIFIC BASIS FOR NUCLEAR WASTE MANAGEMENT XXXI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT 31st Symposium on Scientific Basis for Nuclear Waste Management CY SEP 16-21, 2007 CL Univ Sheffield, Immobilisat Sci Lab, Sheffield, ENGLAND SP Nucl Decommissioning Author, AWE, Nexia Solut, Imperial Coll London, ISL, AMEC, SIA Radon HO Univ Sheffield, Immobilisat Sci Lab ID SPINEL-NEPHELINE LIQUIDUS; NUCLEAR; RATES AB Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. At the Savannah River Site (SRS) actual HLW tank waste has successfully been processed to stringent product and process constraints without any rework into a stable borosilicate glass waste since 1996. A unique "feed forward" statistical process control (SPC) has been used rather than statistical quality control (SQC). In SPC, the feed composition to the melter is controlled prior to vitrification. In SQC, the glass product is sampled after it is vitrified. Individual glass property models form the basis for the "feed forward" SPC. The property models transform constraints on the melt and glass properties into constraints on the feed composition. The property models are mechanistic and depend on glass bonding/structure, thermodynamics, quasicrystalline melt species, and/or electron transfers. The mechanistic models have been validated over composition regions well outside of the regions for which they were developed because they are mechanistic. Mechanistic models allow accurate extension to radioactive and hazardous waste melts well outside the composition boundaries for which they were developed. C1 [Jantzen, Carol M.; Marra, James C.] Savannah River Natl Lab, Aiken, SC 29808 USA. RP Jantzen, CM (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. NR 24 TC 1 Z9 1 U1 2 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 978-1-60511-079-0 J9 MATER RES SOC SYMP P PY 2008 VL 1107 BP 183 EP 190 PG 8 WC Materials Science, Multidisciplinary; Physics, Nuclear SC Materials Science; Physics GA BHZ20 UT WOS:000257618800021 ER PT S AU Marra, JC Fox, KM Peeler, DK Edwards, TB Youchak, AL James, HG Vienna, JD Stefanovsky, SV Aloy, AS AF Marra, James C. Fox, Kevin M. Peeler, David K. Edwards, Thomas B. Youchak, Amanda L. Gillam, James H., Jr. Vienna, John D. Stefanovsky, Sergey V. Aloy, Albert S. BE Lee, WE Roberts, JW Hyatt, NC Grimes, RW TI Glass formulation development in support of melter testing to demonstrate enhanced high level waste throughput SO SCIENTIFIC BASIS FOR NUCLEAR WASTE MANAGEMENT XXXI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT 31st Symposium on Scientific Basis for Nuclear Waste Management CY SEP 16-21, 2007 CL Univ Sheffield, Immobilisat Sci Lab, Sheffield, ENGLAND SP Nucl Decommissioning Author, AWE, Nexia Solut, Imperial Coll London, ISL, AMEC, SIA Radon HO Univ Sheffield, Immobilisat Sci Lab AB The U.S. Department of Energy (DOE) is currently processing high-level waste (HLW) through a Joule-heated melter (JHM) at the Savannah River Site (SRS) and plans to vitrify HLW and Low activity waste (LAW) at the Hanford Site. Over the past few years at the Defense Waste Processing Facility (DWPF), work has concentrated on increasing waste throughput. These efforts are continuing with an emphasis on high alumina concentration feeds. High alumina feeds have presented specific challenges for the JHM technology regarding the ability to increase waste loading yet still maintain product quality and adequate throughput. Alternatively, vitrification technology innovations are also being investigated as a means to increase waste throughput. The Cold Crucible Induction Melter (CCIM) technology affords the opportunity for higher vitrification process temperatures as compared to the current reference JHM technology. Higher process temperatures may allow for higher waste loading and higher melt rate. Glass formuation testing to support melter demonstration testing was recently completed. This testing was specifically aimed at high alumina concentration wastes. Glass composition/property models developed for DWPF were utilized as a guide for formulation development. Both CCIM and JHM testing will be conducted so glass formulation testing was targeted at both technologies with a goal to significantly increase waste loading and maintain melt rate without compromising product quality. C1 [Marra, James C.; Fox, Kevin M.; Peeler, David K.; Edwards, Thomas B.; Youchak, Amanda L.; Gillam, James H., Jr.] Savannah River Natl Lab, Aiken, SC USA. RP Marra, JC (reprint author), Savannah River Natl Lab, Aiken, SC USA. NR 12 TC 5 Z9 5 U1 0 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 978-1-60511-079-0 J9 MATER RES SOC SYMP P PY 2008 VL 1107 BP 231 EP 238 PG 8 WC Materials Science, Multidisciplinary; Physics, Nuclear SC Materials Science; Physics GA BHZ20 UT WOS:000257618800027 ER PT S AU Fox, KM Marra, JC Edwards, TB Hoffman, EN Crawford, CL AF Fox, Kevin M. Marra, James C. Edwards, Thomas B. Hoffman, Elizabeth N. Crawford, Charles L. BE Lee, WE Roberts, JW Hyatt, NC Grimes, RW TI Plutonium feed impurity testing in lanthanide borosilicate (LaBS) glass SO SCIENTIFIC BASIS FOR NUCLEAR WASTE MANAGEMENT XXXI SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT 31st Symposium on Scientific Basis for Nuclear Waste Management CY SEP 16-21, 2007 CL Univ Sheffield, Immobilisat Sci Lab, Sheffield, ENGLAND SP Nucl Decommissioning Author, AWE, Nexia Solut, Imperial Coll London, ISL, AMEC, SIA Radon HO Univ Sheffield, Immobilisat Sci Lab AB A vitrification technology utilizing a lanthanide borosilicate (LaBS) glass is a viable option for dispositioning excess weapons-useable plutonium that is not suitable for processing into mixed oxide (MOX) fuel. A significant effort to develop a glass formulation and vitrification process to immobilize plutonium was completed in the mid-1990s. TheLaBSglass formulation was found to be capable of immobilizing in excess of 10 wt % Pu and to be tolerant of a range of impurities. A more detailed study is now needed to quantify the ability of the glass to accommodate the anticipated impurities associated with the Pu feeds now slated for disposition. The database of Pu feeds was reviewed to identify impurity species and concentration ranges for these impurities. Based on this review, a statistically designed test matrix of glass compositions was developed to evaluate the ability of the LaBS glass to accommodate the impurities. Sixty surrogate LaBS glass compositions were prepared in accordance with the statistically designed test matrix. The heterogeneity (e.g. degree of crystallinity) and durability (as measured by the Product Consistency Test - Method A (PCT-A)) of the glasses were used to assess the effects of impurities on glass quality. C1 [Fox, Kevin M.; Marra, James C.; Edwards, Thomas B.; Hoffman, Elizabeth N.; Crawford, Charles L.] Savannah River Natl Lab, Aiken, SC USA. RP Fox, KM (reprint author), Savannah River Natl Lab, Aiken, SC USA. NR 10 TC 1 Z9 2 U1 3 U2 5 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 978-1-60511-079-0 J9 MATER RES SOC SYMP P PY 2008 VL 1107 BP 397 EP 404 PG 8 WC Materials Science, Multidisciplinary; Physics, Nuclear SC Materials Science; Physics GA BHZ20 UT WOS:000257618800047 ER PT S AU Rebak, RB Ilevbare, GO Carranza, RM AF Rebak, Raul B. Ilevbare, Gabriel O. Carranza, Ricardo M. BE Lee, WE Roberts, JW Hyatt, NC Grimes, RW TI Repassivation potential of Alloy 22 in sodium and calcium chloride brines SO SCIENTIFIC BASIS FOR NUCLEAR WASTE MANAGEMENT XXXI SE Materials Research Society Symposium Proceedings LA English DT Proceedings Paper CT 31st Symposium on Scientific Basis for Nuclear Waste Management CY SEP 16-21, 2007 CL Univ Sheffield, Immobilisat Sci Lab, Sheffield, ENGLAND SP Nucl Decommissioning Author, AWE, Nexia Solut, Imperial Coll London, ISL, AMEC, SIA Radon HO Univ Sheffield, Immobilisat Sci Lab ID LOCALIZED CORROSION SUSCEPTIBILITY; CREVICE CORROSION; ENVIRONMENTS; BEHAVIOR; CRACKING; NICKEL AB A comprehensive matrix of 60 tests was designed to explore the effect of calcium chloride vs sodium chloride and the ratio R of nitrate concentration over chloride concentration on the repassivation potential of Alloy 22. Tests were conducted using the cyclic potentiodynamic polarization (CPP) technique at 75 degrees C and at 90 degrees C. Results show that at a ratio R of 0.18 and higher nitrate was able to inhibit the crevice corrosion in Alloy 22 induced by chloride. Current results fail to show in a consistent way a different effect on the repassivation potential of Alloy 22 for calcium chloride solutions than for sodium chloride solutions. C1 [Rebak, Raul B.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Rebak, RB (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. OI Rebak, Raul/0000-0002-8070-4475 NR 31 TC 0 Z9 0 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 978-1-60511-079-0 J9 MATER RES SOC SYMP P PY 2008 VL 1107 BP 527 EP 535 PG 9 WC Materials Science, Multidisciplinary; Physics, Nuclear SC Materials Science; Physics GA BHZ20 UT WOS:000257618800062 ER PT J AU Hascoet, L Utke, J Naumann, U AF Hascoet, L. Utke, J. Naumann, U. TI Cheaper adjoints by reversing address computations SO SCIENTIFIC PROGRAMMING LA English DT Article DE Program transformation; automatic differentiation; inverse computation AB The reverse mode of automatic differentiation is widely used in science and engineering. A severe bottleneck for the performance of the reverse mode, however, is the necessity to recover certain intermediate values of the program in reverse order. Among these values are computed addresses, which traditionally are recovered through forward recomputation and storage in memory. We propose an alternative approach for recovery that uses inverse computation based on dependency information. Address storage constitutes a significant portion of the overall storage requirements. An example illustrates substantial gains that the proposed approach yields, and we show use cases in practical applications. C1 [Utke, J.] Argonne Natl Lab, MCS, Argonne, IL 60439 USA. [Hascoet, L.] INRIA Sophia Antipolis, F-06902 Valbonne, France. [Naumann, U.] Rhein Westfal TH Aachen, Dept Comp Sci, D-52056 Aachen, Germany. RP Utke, J (reprint author), Argonne Natl Lab, MCS, 9700 S Cass Ave, Argonne, IL 60439 USA. EM utke@mcs.anl.gov FU Office of Advanced Scientific Computing Research, Office of Science, US Dept. of Energy [DE-AC02-06CH11357] FX Jean Utke was supported by the Mathematical, Information and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, US Dept. of Energy under Contract DE-AC02-06CH11357. NR 23 TC 1 Z9 1 U1 0 U2 0 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 1 BP 81 EP 92 DI 10.3233/SPR-2008-0238 PG 12 WC Computer Science, Software Engineering SC Computer Science GA 525OQ UT WOS:000272226200006 ER PT J AU Schulz, M Galarowicz, J Maghrak, D Hachfeld, W Montoya, D Cranford, S AF Schulz, Martin Galarowicz, Jim Maghrak, Don Hachfeld, William Montoya, David Cranford, Scott TI Open vertical bar SpeedShop: An open source infrastructure for parallel performance analysis SO SCIENTIFIC PROGRAMMING LA English DT Article DE Performance tools; scalable infrastructure; tool design; plugin architecture ID VISUALIZATION; TOOL AB Over the last decades a large number of performance tools has been developed to analyze and optimize high performance applications. Their acceptance by end users, however, has been slow: each tool alone is often limited in scope and comes with widely varying interfaces and workflow constraints, requiring different changes in the often complex build and execution infrastructure of the target application. We started the Open vertical bar SpeedShop project about 3 years ago to overcome these limitations and provide efficient, easy to apply, and integrated performance analysis for parallel systems. Open vertical bar SpeedShop has two different faces: it provides an interoperable tool set covering the most common analysis steps as well as a comprehensive plugin infrastructure for building new tools. In both cases, the tools can be deployed to large scale parallel applications using DPCL/Dyninst for distributed binary instrumentation. Further, all tools developed within or on top of Open vertical bar SpeedShop are accessible through multiple fully equivalent interfaces including an easy-to-use GUI as well as an interactive command line interface reducing the usage threshold for those tools. C1 [Schulz, Martin] Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. [Galarowicz, Jim; Maghrak, Don; Hachfeld, William] Krell Inst, Ames, IA USA. [Montoya, David] Los Alamos Natl Lab, Los Alamos, NM USA. [Cranford, Scott] Sandia Natl Labs, Livermore, CA USA. RP Schulz, M (reprint author), Lawrence Livermore Natl Lab, POB 808,L-560, Livermore, CA 94551 USA. EM schulzm@llnl.gov FU US Department of Energy by Lawrence Livermore National Laboratory [DE-AC5207NA27344, (UCRL-JRNL-234840)] FX Part of this work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC5207NA27344 (UCRL-JRNL-234840). NR 20 TC 20 Z9 20 U1 0 U2 3 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 2-3 BP 105 EP 121 DI 10.3233/SPR-2008-0256 PG 17 WC Computer Science, Software Engineering SC Computer Science GA 525OW UT WOS:000272226800002 ER PT J AU Chan, A Gropp, W Lusk, E AF Chan, Anthony Gropp, William Lusk, Ewing TI An efficient format for nearly constant-time access to arbitrary time intervals in large trace files SO SCIENTIFIC PROGRAMMING LA English DT Article DE Trace file; message passing interface; performance visualization ID PERFORMANCE VISUALIZATION; PROGRAMS; PAJE; TOOL AB A powerful method to aid in understanding the performance of parallel applications uses log or trace files containing time-stamped events and states (pairs of events). These trace files can be very large, often hundreds or even thousands of megabytes. Because of the cost of accessing and displaying such files, other methods are often used that reduce the size of the tracefiles at the cost of sacrificing detail or other information. This paper describes a hierarchical trace file format that provides for display of an arbitrary time window in a time independent of the total size of the file and roughly proportional to the number of events within the time window. This format eliminates the need to sacrifice data to achieve a smaller trace file size (since storage is inexpensive, it is necessary only to make efficient use of bandwidth to that storage). The format can be used to organize a trace file or to create a separate file of annotations that may be used with conventional trace files. We present an analysis of the time to access all of the events relevant to an interval of time and we describe experiments demonstrating the performance of this file format. C1 [Chan, Anthony; Gropp, William; Lusk, Ewing] Argonne Natl Lab, Math & Comp Sci Div, Argonne, IL 60439 USA. RP Gropp, W (reprint author), Univ Illinois, Dept Comp Sci, 1304 W Springfield Ave, Urbana, IL 61801 USA. OI Gropp, William/0000-0003-2905-3029 FU US Department of Energy [B523820]; ASC/Alliance Center for Astrophysical Thermonuclear Flashes at the University of Chicago and in part by the Mathematical; Information and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research; Office of Science, US Department of Energy [DE-AC0206CH11357] FX This work was supported in part by the US Department of Energy Contract #B523820 to the ASC/Alliance Center for Astrophysical Thermonuclear Flashes at the University of Chicago and in part by the Mathematical, Information and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, US Department of Energy, under Contract DE-AC0206CH11357. NR 20 TC 19 Z9 19 U1 0 U2 0 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 2-3 BP 155 EP 165 DI 10.3233/SPR-2008-0252 PG 11 WC Computer Science, Software Engineering SC Computer Science GA 525OW UT WOS:000272226800005 ER PT J AU Rouson, DWI AF Rouson, Damian W. I. TI Complexity in scalable computing SO SCIENTIFIC PROGRAMMING LA English DT Editorial Material C1 Sandia Natl Labs, Scalable Comp Res & Dev Dept, Livermore, CA 94550 USA. RP Rouson, DWI (reprint author), Sandia Natl Labs, Scalable Comp Res & Dev Dept, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 4 BP 275 EP 276 DI 10.3233/SPR-2008-0277 PG 2 WC Computer Science, Software Engineering SC Computer Science GA 525PB UT WOS:000272227300001 ER PT J AU Nielsen, IMB Janssen, CL AF Nielsen, Ida M. B. Janssen, Curtis L. TI Multicore challenges and benefits for high performance scientific computing SO SCIENTIFIC PROGRAMMING LA English DT Article DE Multicore technology; hybrid programming model; multi-threading; message-passing; matrix multiplay ID ALGORITHM AB Until recently, performance gains in processors were achieved largely by improvements in clock speeds and instruction level parallelism. Thus, applications could obtain performance increases with relatively minor changes by upgrading to the latest generation of computing hardware. Currently, however, processor performance improvements are realized by using multicore technology and hardware support for multiple threads within each core, and taking full advantage of this technology to improve the performance of applications requires exposure of extreme levels of software parallelism. We will here discuss the architecture of parallel computers constructed from many multicore chips as well as techniques for managing the complexity of programming such computers, including the hybrid message-passing/multi-threading programming model. We will illustrate these ideas with a hybrid distributed memory matrix multiply and a quantum chemistry algorithm for energy computation using Moller-Plesset perturbation theory. C1 [Nielsen, Ida M. B.; Janssen, Curtis L.] Sandia Natl Labs, Livermore, CA 94551 USA. RP Janssen, CL (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. EM cljanss@sandia.gov FU United States Department of Energy's National Nuclear Security Administration [DE-AC04-94AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. NR 9 TC 4 Z9 5 U1 3 U2 4 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 4 BP 277 EP 285 DI 10.3233/SPR-2008-0260 PG 9 WC Computer Science, Software Engineering SC Computer Science GA 525PB UT WOS:000272227300002 ER PT J AU Kenny, JP Janssen, CL Gordon, MS Sosonkina, M Windus, TL AF Kenny, Joseph P. Janssen, Curtis L. Gordon, Mark S. Sosonkina, Masha Windus, Theresa L. TI A component approach to collaborative scientific software development: Tools and techniques utilized by the Quantum Chemistry Science Application Partnership SO SCIENTIFIC PROGRAMMING LA English DT Article DE Electronic structure; integral; component; software development AB Cutting-edge scientific computing software is complex, increasingly involving the coupling of multiple packages to combine advanced algorithms or simulations at multiple physical scales. Component-based software engineering (CBSE) has been advanced as a technique for managing this complexity, and complex component applications have been created in the quantum chemistry domain, as well as several other simulation areas, using the component model advocated by the Common Component Architecture (CCA) Forum. While programming models do indeed enable sound software engineering practices, the selection of programming model is just one building block in a comprehensive approach to large-scale collaborative development which must also address interface and data standardization, and language and package interoperability. We provide an overview of the development approach utilized within the Quantum Chemistry Science Application Partnership, identifying design challenges, describing the techniques which we have adopted to address these challenges and highlighting the advantages which the CCA approach offers for collaborative development. C1 [Kenny, Joseph P.; Janssen, Curtis L.] Sandia Natl Labs, Livermore, CA 94551 USA. [Gordon, Mark S.; Windus, Theresa L.] Iowa State Univ, Dept Chem, Ames, IA USA. [Gordon, Mark S.; Sosonkina, Masha] Iowa State Univ, Scalable Comp Lab, Ames Lab, US DOE, Ames, IA USA. RP Kenny, JP (reprint author), Sandia Natl Labs, MS 9158,POB 969, Livermore, CA 94551 USA. EM jpkenny@sandia.gov FU US Department of Energy's Scientific Discovery through Advanced Computing (SciDAC); US Department of Energy [DE-AC04-94AL85000] FX This work has been supported in part by the US Department of Energy's Scientific Discovery through Advanced Computing (SciDAC) initiative [28], through the Chemistry Framework using Common Component Architecture scientific application project, of which Ames Laboratory and Sandia National Laboratories are participants. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy under contract DE-AC04-94AL85000. NR 21 TC 2 Z9 2 U1 1 U2 3 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 4 BP 287 EP 296 DI 10.3233/SPR-2008-0264 PG 10 WC Computer Science, Software Engineering SC Computer Science GA 525PB UT WOS:000272227300003 ER PT J AU Adalsteinsson, H Debusschere, BJ Long, KR Najm, HN AF Adalsteinsson, Helgi Debusschere, Bert J. Long, Kevin R. Najm, Habib N. TI Components for atomistic-to-continuum multiscale modeling of flow in micro- and nanofluidic systems SO SCIENTIFIC PROGRAMMING LA English DT Article DE Multiscale; multiphysics; electrodynamic transport; microfluidics; desalination; puppeteer ID POISSON-NERNST-PLANCK; BROWNIAN DYNAMICS; NUMERICAL-SIMULATION; MICROFLUIDIC DEVICES; ION CHANNELS; ELECTROPHORESIS; PARTICLE; TESTS AB Micro- and nanofluidics pose a series of significant challenges for science-based modeling. Key among those are the wide separation of length- and timescales between interface phenomena and bulk flow and the spatially heterogeneous solution properties near solid-liquid interfaces. It is not uncommon for characteristic scales in these systems to span nine orders of magnitude from the atomic motions in particle dynamics up to evolution of mass transport at the macroscale level, making explicit particle models intractable for all but the simplest systems. Recently, atomistic-to-continuum (A2C) multiscale simulations have gained a lot of interest as an approach to rigorously handle particle-level dynamics while also tracking evolution of large-scale macroscale behavior. While these methods are clearly not applicable to all classes of simulations, they are finding traction in systems in which tight-binding, and physically important, dynamics at system interfaces have complex effects on the slower-evolving large-scale evolution of the surrounding medium. These conditions allow decomposition of the simulation into discrete domains, either spatially or temporally. In this paper, we describe how features of domain decomposed simulation systems can be harnessed to yield flexible and efficient software for multiscale simulations of electric field-driven micro-and nanofluidics. C1 [Adalsteinsson, Helgi; Debusschere, Bert J.; Najm, Habib N.] Sandia Natl Labs, Livermore, CA 94551 USA. [Long, Kevin R.] Texas Tech Univ, Dept Math & Stat, Lubbock, TX 79409 USA. RP Adalsteinsson, H (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. EM hadalst@sandia.gov FU U.S. Department of Energy [DE-AC04-94AL85000] FX Work on multiscale simulations of electroosmotic flow was supported by the National Nuclear Security Administration's Advanced Simulation and Computing (ASC) program through Sandia's Computational Science Research Foundation program. Simulations of electrodialysis through nanoporous membranes was supported by the laboratory's program on Water Surety through Laboratory Directed Research and Development funding. Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the U.S. Department of Energy under contract number DE-AC04-94AL85000. NR 42 TC 7 Z9 7 U1 1 U2 5 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 4 BP 297 EP 313 DI 10.3233/SPR-2008-0259 PG 17 WC Computer Science, Software Engineering SC Computer Science GA 525PB UT WOS:000272227300004 ER PT J AU Allan, BA Norris, B Elwasif, WR Armstrong, RC AF Allan, Benjamin A. Norris, Boyana Elwasif, Wael R. Armstrong, Robert C. TI Managing scientific software complexity with Bocca and CCA SO SCIENTIFIC PROGRAMMING LA English DT Article DE Code generation; software development environment; interface definition language; SIDL AB In high-performance scientific software development, the emphasis is often on short time to first solution. Even when the development of new components mostly reuses existing components or libraries and only small amounts of new code must be created, dealing with the component glue code and software build processes to obtain complete applications is still tedious and error-prone. Component-based software meant to reduce complexity at the application level increases complexity to the extent that the user must learn and remember the interfaces and conventions of the component model itself. To address these needs, we introduce Bocca, the first tool to enable application developers to perform rapid component prototyping while maintaining robust software-engineering practices suitable to HPC environments. Bocca provides project management and a comprehensive build environment for creating and managing applications composed of Common Component Architecture components. Of critical importance for high-performance computing (HPC) applications, Bocca is designed to operate in a language-agnostic way, simultaneously handling components written in any of the languages commonly used in scientific applications: C, C++, Fortran, Python and Java. Bocca automates the tasks related to the component glue code, freeing the user to focus on the scientific aspects of the application. Bocca embraces the philosophy pioneered by Ruby on Rails for web applications: start with something that works, and evolve it to the user's purpose. C1 [Allan, Benjamin A.; Armstrong, Robert C.] Sandia Natl Labs, Livermore, CA 94551 USA. [Norris, Boyana] Argonne Natl Lab, Argonne, IL 60439 USA. [Elwasif, Wael R.] Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Allan, BA (reprint author), Sandia Natl Labs, 7011 E Ave,MS 9158, Livermore, CA 94551 USA. EM baallan@sandia.gov OI Norris, Boyana/0000-0001-5811-9731 FU Office of Advanced Scientific Computing Research, Office of Science, US Department of Energy [DE-AC02-06CH11357]; Oak Ridge National Laboratory; US Department of Energy [DE-AC05-00OR22725, DE-AC04-94AL85000] FX This work was supported in part by the Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, US Department of Energy, under Contract DE-AC02-06CH11357 (Argonne National Laboratory); Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the US Department of Energy under contract DE-AC05-00OR22725. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy under contract DE-AC04-94AL85000. NR 16 TC 3 Z9 3 U1 0 U2 10 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1058-9244 J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 4 BP 315 EP 327 DI 10.3233/SPR-2008-0270 PG 13 WC Computer Science, Software Engineering SC Computer Science GA 525PB UT WOS:000272227300005 ER PT J AU Rouson, DWI AF Rouson, Damian W. I. TI Towards analysis-driven scientific software architecture: The case for abstract data type calculus SO SCIENTIFIC PROGRAMMING LA English DT Article DE Objected-oriented programming; design metrics; complexity; information theory; Fortran ID METRICS AB This article approaches scientific software architecture from three analytical paths. Each path examines discrete time advancement of multiphysics phenomena governed by coupled differential equations. The new object-oriented Fortran 2003 constructs provide a formal syntax for an abstract data type (ADT) calculus. The first analysis uses traditional object-oriented software design metrics to demonstrate the high cohesion and low coupling associated with the calculus. A second analysis from the viewpoint of computational complexity theory demonstrates that a more representative bug search strategy than that considered by Rouson et al. (ACM Trans. Math. Soft. 34(1) (2008)) reduces the number of lines searched in a code with lambda total lines from O(lambda(2)) to O(lambda log(2) lambda), which in turn becomes nearly independent of the overall code size in the context of ADT calculus. The third analysis derives from information theory an argument that ADT calculus simplifies developer communications in part by minimizing the growth in interface information content as developers add new physics to a multiphysics package. C1 Sandia Natl Labs, Scalable Comp Res & Dev Dept, Livermore, CA 94550 USA. RP Rouson, DWI (reprint author), Sandia Natl Labs, Scalable Comp Res & Dev Dept, MS 9158,POB 969, Livermore, CA 94550 USA. FU Office of Naval Research [61-8804065] FX The author gratefully acknowledges the support of the Office of Naval Research via Contract 61-8804065. The author also thanks Dr. Jeanie Osburn of the US Naval Research Laboratory for pointing out that the bisection method more closely resembles common practice in searching for bugs and Dr. Robert Armstrong of Sandia National Laboratories for many thought-provoking discussions on programming languages, operator overloading, and the limits of software estimation. NR 21 TC 2 Z9 2 U1 1 U2 3 PU HINDAWI PUBLISHING CORP PI NEW YORK PA 410 PARK AVENUE, 15TH FLOOR, #287 PMB, NEW YORK, NY 10022 USA SN 1058-9244 EI 1875-919X J9 SCI PROGRAMMING-NETH JI Sci. Program. PY 2008 VL 16 IS 4 BP 329 EP 339 DI 10.3233/SPR-2008-0262 PG 11 WC Computer Science, Software Engineering SC Computer Science GA 525PB UT WOS:000272227300006 ER PT B AU Seymour, N Stern, D De Breuck, C Vernet, J Fosbury, R Rettura, A Zirm, A Rocca-Volmerange, B Lacy, M Teplitz, H Dey, A Dickinson, A van Brengel, W Miley, G Rottgering, H Eisenhardt, P McCarthy, P De Breuck, F Vernet, L AF Seymour, N. Stern, D. De Breuck, C. Vernet, J. Fosbury, R. Rettura, A. Zirm, A. Rocca-Volmerange, B. Lacy, M. Teplitz, H. Dey, A. Dickinson, A. van Brengel, W. Miley, G. Rottgering, H. Eisenhardt, P. McCarthy, P. De Breuck, F. Vernet, L. BE Chary, RR Teplitz, HI Sheth, K TI Spitzer observations of high redshift radio galaxies SO SECOND ANNUAL SPITZER SCIENCE CENTER CONFERENCE: INFRARED DIAGNOSTICS OF GALAXY EVOLUTION SE Astronomical Society of the Pacific Conference Series LA English DT Proceedings Paper CT 2nd Annual Spitzer Science Center Conference on Infrared Diagnostics of Galaxy Evolution CY NOV 14-16, 2005 CL Pasadena, CA ID ELLIPTIC GALAXIES; STAR-FORMATION; JETS AB We present the results of a comprehensive Spitzer survey of 70 radio galaxies across 1 < z < 5.2. Using IRAC, IRS and MIPS imaging we determine the rest-frame AGN contribution to the stellar emission peak at 1.6 mu m. The stellar luminosities are found to be consistent with that of a giant elliptical with a stellar mass of 10(11-12) M-circle dot. The mean stellar mass remains constant at 10(11-5) M-circle dot up to z = 3 indicating that the upper end of the mass function is already in place at redshift 3. The mid-IR luminosities imply bolometric IR luminosities that would classify most sources as ULIRGs. The mid-IR to radio luminosity generally correlate implying a common origin for these emissions. The ratio is higher than that found for lower redshift, i.e. z < 1, radio galaxies. C1 [Seymour, N.; Stern, D.; Lacy, M.; Teplitz, H.] CALTECH, Spitzer Sci Ctr, Mail Code 220-6,1200 E Calif Blvd, Pasadena, CA 91125 USA. [Stern, D.; Eisenhardt, P.] Jet Prop Lab, Pasadena, CA 91125 USA. [De Breuck, C.; Vernet, J.; Fosbury, R.; Rettura, A.; De Breuck, F.; Vernet, L.] ESO, Munich, Germany. [Rettura, A.; Rocca-Volmerange, B.] IAP, Delhi, India. [Zirm, A.] Space Telescope Sci Inst, Baltimore, MD 21218 USA. [Dey, A.; Dickinson, A.] Natl Opt Astron Observ, Tucson, AZ 85719 USA. [van Brengel, W.] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. [Miley, G.; Rottgering, H.] Leiden Univ, NL-2300 RA Leiden, Netherlands. [McCarthy, P.] OCIW, Pittsburgh, PA 15213 USA. RP Seymour, N (reprint author), CALTECH, Spitzer Sci Ctr, Mail Code 220-6,1200 E Calif Blvd, Pasadena, CA 91125 USA. NR 17 TC 0 Z9 0 U1 0 U2 2 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 978-1-58381-325-6 J9 ASTR SOC P PY 2008 VL 381 BP 398 EP + PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BHO46 UT WOS:000254828200075 ER PT J AU Fleming, P Lammlein, D Wilkes, D Fleming, K Bloodworth, T Cook, G Strauss, A DeLapp, D Lienert, T Bement, M Prater, T AF Fleming, Paul Lammlein, David Wilkes, D. Fleming, Katherine Bloodworth, Thomas Cook, George Strauss, Al DeLapp, David Lienert, Thomas Bement, Matthew Prater, Tracie TI In-process gap detection in friction stir welding SO SENSOR REVIEW LA English DT Article DE friction welding; robotics; feedback; spectra AB Purpose - This paper aims to investigate methods of implementing in-process fault avoidance in robotic friction stir welding (FSW). Design/methodology/approach - Investigations into the possibilities for automatically detecting gap-faults in a friction stir lap weld were conducted. Force signals were collected from a number of lap welds containing differing degrees of gap faults. Statistical analysis was carried out to determine whether these signals could be used to develop an automatic fault detector/classifier. Findings - The results demonstrate that the frequency spectra of collected force signals can be mapped to a lower dimension through discovered discriminant functions where the faulty welds and control welds are linearly separable. This implies that a robust and precise classifier is very plausible, given force signals. Research limitations/implications - Future research should focus on a complete controller using the information reported in this paper. This should allow for a robotic friction stir welder to detect and avoid faults in real time. This would improve manufacturing safety and yield. Practical implications - This paper is applicable to the rapidly expanding robotic FSW industry. A great advantage of heavy machine tool versus robotic FSW is that the robot cannot supply the same amount of rigidity. Future work must strive to overcome this lack of mechanical rigidity with intelligent control, as has been examined in this paper. Originality/value - This paper investigates fault detection in robotic FSW. Fault detection and avoidance are essential for the increased robustness of robotic FSW. The paper's results describe very promising directions for such implementation. C1 [Fleming, Paul; Lammlein, David; Wilkes, D.; Bloodworth, Thomas; Cook, George; Strauss, Al; DeLapp, David] Vanderbilt Univ, Welding Automat Lab, Nashville, TN 37203 USA. [Fleming, Katherine] Vanderbilt Univ, Ctr Intelligent Syst, Nashville, TN USA. [Bloodworth, Thomas; Lienert, Thomas] Los Alamos Natl Lab, Los Angeles, CA USA. RP Fleming, P (reprint author), Vanderbilt Univ, Welding Automat Lab, 221 Kirkland Hall, Nashville, TN 37203 USA. EM paul.a.fleming@vanderbilt.ed OI Bement, Matthew/0000-0003-3577-3292; Fleming, Paul/0000-0001-8249-2544 NR 11 TC 14 Z9 14 U1 3 U2 11 PU EMERALD GROUP PUBLISHING LIMITED PI BINGLEY PA HOWARD HOUSE, WAGON LANE, BINGLEY BD16 1WA, W YORKSHIRE, ENGLAND SN 0260-2288 J9 SENSOR REV JI Sens. Rev. PY 2008 VL 28 IS 1 BP 62 EP 67 DI 10.1108/026022808108500441 PG 6 WC Instruments & Instrumentation SC Instruments & Instrumentation GA 286OM UT WOS:000254855200012 ER PT S AU McMakin, DL Hall, TE Sheen, DM AF McMakin, Douglas L. Hall, Thomas E. Sheen, David M. BE Carapezza, EM TI Holographic radar imaging privacy techniques utilizing dual-frequency implementation SO SENSORS, AND COMMAND, CONTROL, COMMUNICATIONS, AND INTELLIGENCE (C3I) TECHNOLOGIES FOR HOMELAND SECURITY AND HOMELAND DEFENSE VII SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Sensors, and Command, Control, Communications and Intelligence (C31) Technologies for Homeland Security and Homeland Defense VI CY MAR 17-20, 2008 CL Orlando, FL SP SPIE DE privacy algorithms; millimeter waves; personnel surveillance; holography; radar imaging AB Over the last 15 years, the Pacific Northwest National Laboratory has performed significant research and development activities to enhance the state of the art of holographic radar imaging systems to be used at security checkpoints for screening people for concealed threats hidden under their garments. These enhancement activities included improvements to privacy techniques to remove human features and providing automatic detection of body-worn concealed threats. The enhanced privacy and detection methods used both physical and software imaging techniques. The physical imaging techniques included polarization-diversity illumination and reception, dual-frequency implementation, and high-frequency imaging at 60 GHz. Software imaging techniques to enhance the privacy of the person under surveillance included extracting concealed threat artifacts from the imagery to automatically detect the threat. This paper will focus on physical privacy techniques using dual-frequency implementation. C1 [McMakin, Douglas L.; Hall, Thomas E.; Sheen, David M.] Pacific NW Natl Lab, Richland, WA 99354 USA. RP McMakin, DL (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd, Richland, WA 99354 USA. EM doug.mcmakin@pnl.gov NR 7 TC 0 Z9 0 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7134-5 J9 PROC SPIE PY 2008 VL 6943 AR 69430P DI 10.1117/12.777412 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Computer Science; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BHY04 UT WOS:000257370800019 ER PT J AU Chen, H Ebner, AD Ritter, JA Kaminski, MD Rosengart, AJ AF Chen, Haitao Ebner, Armin D. Ritter, James A. Kaminski, Michael D. Rosengart, Axel J. TI Theoretical analysis of a magnetic separator device for ex-vivo blood detoxification SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article DE magnetic separator; defoxification; magnetic microspheres; magnetic separator ID CELL TRACKING VELOCIMETRY; SALMONELLA-TYPHIMURIUM; RAPID DETECTION; BONE-MARROW; IN-VITRO; ANTIBODY; NANOPARTICLES; IMMUNOASSAY; CANCER; NANOTECHNOLOGY AB The feasibility of a magnetic separator device for ex-vivo blood detoxification was studied. This blood detoxification approach entails administering functionalized magnetic microspheres (FMMSs) into a patient's body by transdermal injection to capture and remove toxins from the blood using highly specific receptors attached to the surface of the FMMSs. These toxin-loaded FMMSs are then removed from the body using extracorporeal blood circulation through a specially designed magnetic separator, based on high gradient magnetic separation principles. The performance of the magnetic separator, in terms of its collection efficiency (CE) of the FMMSs, was evaluated theoretically using a streamline analysis of a 2-D model. The effects of blood velocity (1 to 20cm/s), magnetic field strength (0.1 to 2.0T), wire size (0.125 to 2.0mm in radii), separator unit size at a fixed ratio of tube to wire diameter of one, tube length (2.0 to 20cm), wire material (nickel, SS 430 and wairauite), and magnetic material comprising the FMMSs (iron, typical magnetite and weaker magnetite) on the CE were evaluated. Provided that the blood velocity was below 2cm/s, CEs > 80% could be attained under reasonable conditions, like when using FMMSs 400nm in diameter and containing 60wt% magnetite in a magnetic field of 0.5T using a magnetic separator with 0.5mm radii wire (at a fixed ratio of tube to wire diameter of close to one) that was 10cm in length (same as the tube) and made of SS 430. CEs of between 30% and 80% could also be attained at blood velocities up to 20cm/s without compromising the magnetic separator design. The magnetic separator performance improved by reducing the size of the unit with tubes and wires of equal radii, increasing the applied magnetic field strength, utilizing magnetic materials with the highest magnetizations, and increasing the length of the unit. Overall, the results from this study delineated the physically realistic conditions that make ex vivo blood detoxification possible with this magnetic separator device. C1 [Chen, Haitao; Rosengart, Axel J.] Univ Chicago, Dept Neurol, Med Ctr, Chicago, IL 60637 USA. [Rosengart, Axel J.] Univ Chicago, Dept Surg Neurosurg, Chicago, IL 60637 USA. [Chen, Haitao] IIT, Dept Biomed Engn, Chicago, IL 60616 USA. [Ebner, Armin D.; Ritter, James A.] Univ S Carolina, Dept Chem Engn, Columbia, SC 29208 USA. [Kaminski, Michael D.] Argonne Natl Lab, Div Chem Engn, Argonne, IL 60439 USA. RP Rosengart, AJ (reprint author), Univ Chicago, Dept Neurol, Med Ctr, Chicago, IL 60637 USA. EM arosenga@neurology.bsd.uchicago.edu NR 55 TC 14 Z9 14 U1 0 U2 6 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 0149-6395 EI 1520-5754 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 5 BP 996 EP 1020 DI 10.1080/01496390801910609 PG 25 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 283JI UT WOS:000254632100002 ER PT J AU Aaron, D Yiacoumi, S Tsouris, C AF Aaron, D. Yiacoumi, S. Tsouris, C. TI Effects of proton-exchange membrane fuel-cell operating conditions on charge transfer resistances measured by electrochemical impedance spectroscopy SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE PEM fuel cell; electrochemical impedance spectroscopy; internal resistance ID HYDROGEN ELECTRODES; EIS INVESTIGATIONS; STEADY-STATE AB Proton-exchange-membrane fuel cells (PEMFC) are highly dependent on operating conditions, such as humidity and temperature. This study employs electrochemical impedance spectroscopy (EIS) to measure the effects of operating parameters on internal proton and electron transport resistance mechanisms in the PEMFC. Current-density experiments have been performed to measure the power production in a 25cm(2) Nafion 117 PEMFC at varying operating conditions. These experiments have shown that low humidity and low temperature contribute to decreased power production. EIS is currently employed to provide a better understanding of the mechanisms involved in power production by calculating the specific resistances at various regions in the PEMFC. Experiments are performed at temperatures ranging from 30 to 50 degrees C, feed humidities from 20 to 98%, and air stoichiometric ratios from 1.33 to 2.67. In all experiments, the hydrogen feed stoichiometric ratio was approximately 4.0. EIS is used to identify which transport steps limit the power production of the PEMFC over these ranges of conditions. The experimental data are analyzed via comparison to equivalent circuit models (ECMs), a technique that uses an electrical circuit to represent the electrochemical and transport properties of the PEMFC. These studies will aid in designing fuel cells that are more tolerant to wide-ranging operating conditions. In addition, optimal operating conditions for PEMFC operation can be identified. C1 [Tsouris, C.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. [Aaron, D.; Yiacoumi, S.; Tsouris, C.] Georgia Inst Technol, Sch Civil & Environm Engn, Atlanta, GA 30332 USA. RP Tsouris, C (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM tsourisc@ornl.gov RI Tsouris, Costas/C-2544-2016 OI Tsouris, Costas/0000-0002-0522-1027 NR 11 TC 3 Z9 3 U1 0 U2 9 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2307 EP 2320 DI 10.1080/01496390802148613 PG 14 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900005 ER PT J AU Fountain, MS Kurath, DE Sevigny, GJ Poloski, AP Pendleton, J Balagopal, S Quist, M Clay, D AF Fountain, M. S. Kurath, D. E. Sevigny, G. J. Poloski, A. P. Pendleton, J. Balagopal, S. Quist, M. Clay, D. TI Caustic recycle from Hanford tank waste using NaSICON ceramic membranes SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE alkaline; caustic recycle; ceramic; electrochemistry; inorganic; membrane; NaSICON AB A sodium (Na) Super Ion Conductor (NaSICON), has been studied at Pacific Northwest National Laboratory (PNNL) to investigate its ability to separate sodium from radioactively contaminated sodium salt solutions for treating U.S. Department of Energy (DOE) tank wastes. Ceramatec Inc. developed and fabricated a membrane disk containing a proprietary NAS-GY material formulation that was electrochemically tested in a bench-scale apparatus with both a simulant and a radioactive tank-waste solution to determine the membrane performance when removing sodium from DOE tank wastes. Implementing this sodium separation process can result in significant cost savings by reducing the disposal volume of low-activity wastes and by producing a 19M NaOH feedstock product for recycle into waste treatment processes such as sludge leaching, regenerating ion exchange resins, inhibiting corrosion in carbon-steel tanks, or retrieving tank wastes. In actual waste tests, average sodium transport rates of 10.3kg/day/m(2) were achieved at average sodium transport efficiencies of 99%. The membrane was found to be highly selective to sodium ions resulting in no detectable cation transport except Na and a small quantity (0.04% to 0.06%) of (137)Cs. An average decontamination factor of 2000 was observed with respect to (137)Cs. As expected, Gibbsite precipitation was observed as OH- ions were depleted from the tank waste. C1 [Fountain, M. S.; Kurath, D. E.; Sevigny, G. J.; Poloski, A. P.] Pacific NW Natl Lab, Richland, WA 99352 USA. [Pendleton, J.; Balagopal, S.; Quist, M.; Clay, D.] Ceramatec Inc, Salt Lake City, UT 84119 USA. RP Fountain, MS (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM matthew.fountain@pnl.gov NR 8 TC 7 Z9 7 U1 2 U2 12 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2321 EP 2342 DI 10.1080/01496390802121438 PG 22 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900006 ER PT J AU Griffith, WL Compere, AL AF Griffith, W. L. Compere, A. L. TI Separation of alcohols from solution by lignin gels SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE alcohol; extraction; lignin AB Partition relationships of radioisotope labeled ethanol and 1-butanol between aqueous solutions and a hydrated commercial Kraft softwood lignin gel are presented. These initial evaluations indicate that lignin hydrogels preferentially concentrate 1-butanol and, to a lesser extent, ethanol. The process implications and potential use of lignin as an inexpensive extractant are discussed. C1 [Griffith, W. L.; Compere, A. L.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Compere, AL (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM compereal@ornl.gov NR 10 TC 4 Z9 6 U1 1 U2 7 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2396 EP 2405 DI 10.1080/01496390802148571 PG 10 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900011 ER PT J AU Luo, HM Huang, JF Dai, S AF Luo, Huimin Huang, Jing-Fang Dai, Sheng TI Studies on thermal properties of selected aprotic and protic ionic liquids SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE ionic liquids; TGA/DSCs; thermal properties ID SOLVENT-EXTRACTION; AQUEOUS-SOLUTIONS; THERMODYNAMICS; CONDUCTIVITY; SR2+ AB We describe herein the thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) investigations of the thermal properties of selected room-temperature ionic liquids (RTILs). The dependence of the thermal properties on both cation and anion structures of RTILs was systematically studied. The ionic liquids (ILs) investigated here include 28 different imidazolium-based ILs, 22 ammonium-based ILs, and 16 amide-based ILs. In general, these three cation classes exhibit different thermal behaviors but follow a quite systematic trend as expected from the corresponding structural variation. The ILs with bromide as the conjugate anion have lower thermal stabilities than those with bis(trifluoromethane sulfonyl) imide or bis(perfluoroethyl sulfonyl) imide as the conjugate anion. The mass of TGA samples and scan rate were found to have a systematic effect on the decomposition temperature of ILs, highlighting the caution needed in reporting TGA results. C1 [Luo, Huimin] Oak Ridge Natl Lab, Nucl Sci & Technol Div, Oak Ridge, TN 37831 USA. [Huang, Jing-Fang; Dai, Sheng] Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. RP Luo, HM (reprint author), Oak Ridge Natl Lab, Nucl Sci & Technol Div, Oak Ridge, TN 37831 USA. EM luoh@ornl.gov RI Dai, Sheng/K-8411-2015 OI Dai, Sheng/0000-0002-8046-3931 NR 18 TC 20 Z9 20 U1 2 U2 23 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2473 EP 2488 DI 10.1080/01496390802151922 PG 16 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900015 ER PT J AU Burns, CT Choi, SY Dietz, ML Firestone, MA AF Burns, Christopher T. Choi, Sung Yeun Dietz, Mark L. Firestone, Millicent A. TI Acidichromic spiropyran-functionalized mesoporous silica: Towards stimuli-responsive metal ion separations media SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE acidichromic; mesoporous silica ID SELF-ASSEMBLED MONOLAYERS; ACTINIDE SEQUESTRATION; SELECTIVE ADSORPTION; AQUEOUS-SOLUTION; SUPPORTS; SBA-15; DERIVATIVES; CHEMISTRY; SORBENT; SURFACE AB An acidichromic silyl spiropyran was synthesized and covalently immobilized on the surface of mesoporous silica (SBA-15) through either post-modification or a co-condensation route. The integration of the spiropyran into the porous silica was probed by thermogravimetric analysis, nitrogen adsorption/desorption studies and UV-Vis optical spectroscopy. While the co-condensation route provides the higher spiropyran loading levels, it also leads to two different states of attachment. Both synthetic procedures favor the formation of the open, merocyanine form of the spiropyran within the framework, but this form can be readily switched from a protonated to a deprotonated state by treatment with buffered aqueous solutions. Preliminary evaluation of the metal ion sorption capabilities of the spiro-functionalized SBA-15 for selected monovalent, divalent, and trivalent metal ions indicates that the spiropyran-modified materials show modestly improved cation exchange characteristics versus the unfunctionalized mesoporous framework. C1 [Burns, Christopher T.; Choi, Sung Yeun; Dietz, Mark L.; Firestone, Millicent A.] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Firestone, MA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM firestone@anl.gov NR 37 TC 5 Z9 6 U1 2 U2 13 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2503 EP 2519 DI 10.1080/01496390802122311 PG 17 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900017 ER PT J AU Dzielawa, JA Rubas, AV Lubbers, C Stepinski, DC Scurto, AM Barrans, RE Dietz, ML Herlinger, AW Brennecke, JF AF Dzielawa, Julie A. Rubas, Audris V. Lubbers, Christopher Stepinski, Dominique C. Scurto, Aaron M. Barrans, Richard E., Jr. Dietz, Mark L. Herlinger, Albert W. Brennecke, Joan F. TI Carbon dioxide solubility enhancement through silicone functionalization: "CO2-philic" oligo(dimethylsiloxane)-substituted diphosphonates SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE supercritical carbon dioxide; solubility; silicone functionalization ID SUBSTITUTED ALKYLENEDIPHOSPHONIC ACIDS; CO2-SOLUBLE CHELATING-AGENTS; METAL-ION EXTRACTION; AGGREGATION; AMPHIPHILES; COMPLEXES; BEHAVIOR; DESIGN; LIQUID; CO2 AB Carbon dioxide has received significant attention as a potential environmentally benign medium to replace hazardous organic compounds, but is a relatively poor solvent. The addition of siloxane substituents provides an attractive and inexpensive means to solubilize a wide variety of compounds in CO2. By synthesizing and testing a family of gem-diphosphonate ligands that have been rendered CO2-philic by incorporation of a number of related, discrete dimethylsiloxane oligomers, we show that small variations in substituents have a significant effect on the CO2-philicity of the ligand. To our knowledge, this is the first systematic study of the effect of siloxane substituent size, branching, and position on the affinity of a ligand for CO2. In addition, we present a general approach to the preparation of novel gem-diphosphonate ligands. C1 [Dzielawa, Julie A.; Stepinski, Dominique C.; Herlinger, Albert W.] Loyola Univ, Dept Chem, Chicago, IL 60626 USA. [Dzielawa, Julie A.; Rubas, Audris V.; Stepinski, Dominique C.; Barrans, Richard E., Jr.; Dietz, Mark L.] Argonne Natl Lab, Chem Sci & Engn Div, Argonne, IL 60439 USA. [Lubbers, Christopher; Scurto, Aaron M.; Brennecke, Joan F.] Univ Notre Dame, Dept Chem Engn, Notre Dame, IN 46556 USA. RP Dietz, ML (reprint author), Univ Wisconsin, Dept Chem & Biochem, Milwaukee, WI 53211 USA. EM dietzm@uwm.edu RI Scurto, Aaron/F-7984-2016 OI Scurto, Aaron/0000-0001-7214-1871 NR 37 TC 13 Z9 13 U1 0 U2 8 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2520 EP 2536 DI 10.1080/01496390802122063 PG 17 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900018 ER PT J AU Mitchell, JA Johnson, J Counce, RM Watson, JS Spencer, BB Del Cul, GD AF Mitchell, Jessica A. Johnson, Jared Counce, R. M. Watson, J. S. Spencer, B. B. Del Cul, G. D. TI Extracting acetic acid from acidic solutions SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE acetic acid; distribution coefficient; dodecane; dichloroethane; nitric acid; phenyltrifluoromethyl sulfone; solvent extraction; tributyl phosphate ID WATER; EQUILIBRIA AB In the UREX+process, acetic acid must be removed from the raffinate stream to avoid interference with the recovery and recycle of nitric acid solutions. Solvent extraction was selected to be the most promising approach to accomplish this cleanup. Acetic acid partitioning into pure diluents used in the UREX+process were found to be too low for an effective separation. Of the solvents tested, the most promising solvents for the extraction of acetic acid were found to be TBP in dodecane and TBP in FS-13. C1 [Mitchell, Jessica A.] Univ Tennessee, Dept Chem & Biomol Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Nucl Sci & Technol Div, Oak Ridge, TN USA. RP Mitchell, JA (reprint author), Univ Tennessee, Dept Chem & Biomol Engn, Knoxville, TN 37996 USA. EM jmitch30@utk.edu NR 15 TC 5 Z9 5 U1 0 U2 4 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2537 EP 2547 DI 10.1080/01496390802121586 PG 11 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900019 ER PT J AU Johnson, JA Mitchell, JA Counce, RM Watson, JS Spencer, BB Del Cul, GD AF Johnson, Jared A. Mitchell, Jessica A. Counce, Robert M. Watson, Jack S. Spencer, Barry B. Del Cul, G. D. TI Thermodynamics of acetic acid (aq) calculated from the modified adsorption isotherm model for aqueous electrolytes SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE acetic acid; activity coefficients; adsorption isotherm; aqueous electrolytes; Brunauer-Emmett-Teller (BET); eutectic; liquidus curve ID WATER; SALT; MIXTURES AB The modified adsorption isotherm model, incorporating the Stokes-Robinson modification of the Brunauer-Emmett-Teller (BET) adsorption isotherm, is used to calculate the activity of the organic acid and water, and the liquidus curve. This is the first known use of the modified adsorption isotherm for estimation of thermodynamic information for aqueous organic acid solutions and one of few works using the model for predicting information for aqueous acids in general. The method described here represents a simplified approach to estimating thermodynamic properties. The model offers some improvement over regular solution theory, but perhaps more importantly offers a method for adjusting thermodynamic properties in the presence of other components in the future. While other models such as UNIQUAC may prove to be more accurate, this model provides satisfactory results with more ease. C1 [Johnson, Jared A.; Mitchell, Jessica A.; Counce, Robert M.; Watson, Jack S.] Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. [Counce, Robert M.; Spencer, Barry B.; Del Cul, G. D.] Oak Ridge Natl Lab, Nucl Sci & Technol Div, Oak Ridge, TN USA. RP Johnson, JA (reprint author), Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. EM jjohns87@utk.edu NR 16 TC 1 Z9 1 U1 0 U2 6 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2548 EP 2556 DI 10.1080/01496390802148522 PG 9 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900020 ER PT J AU Herbst, RS Peterman, DR Robinson, TA AF Herbst, R. S. Peterman, D. R. Robinson, Troy A. TI PEG-400 partitioning in the HCCD/PEG process for Cs and Sr recovery SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE cesium removal; chlorinated cobalt dicarbollide; PEG-400; radio-nuclide separations; solvent extraction; strontium removal ID EXTRACTION UNEX PROCESS; STRONTIUM; SOLVENT; CESIUM; WASTE; SEPARATION; ACTINIDES AB The properties of the chloro-protected cobalt bis(dicarbollide) anion in the acidic form (HCCD), and in the presence of polyethylene glycol (PEG-400), are well known for the recovery of Cs and Sr from acidic radioactive streams. In the early development of HCCD/PEG extraction processes, questions were raised regarding the ability to control the concentration of PEG-400 in the organic phase due to its high solubility in the aqueous process solutions relative to HCCD or the diluent. The purpose of this study was to quantify the partitioning behavior of PEG-400 under a wide variety of relevant process conditions. PEG distribution ratios (D(PEG)) were measured by equilibrium batch contacts between the organic and aqueous phases over a wide range of conditions using radiometric techniques with (14)C labeled PEG-400 to monitor the behavior of the bulk material. The results vary dramatically from 0.1 < D(PEG) < 50, indicate that the PEG phase transfer kinetics are rapid, and that the aqueous phase nitric acid concentration has minimal impact on PEG solubility. The molar concentration ratio of [HCCD]:[PEG] in the organic phase has the greatest impact on PEG solubility. This ratio should be maintained at [HCCD]:[PEG] greater than or equal to approximately 6 to minimize PEG losses from the organic phase. C1 [Herbst, R. S.; Peterman, D. R.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. [Robinson, Troy A.] Univ Nevada, Las Vegas, NV 89154 USA. RP Herbst, RS (reprint author), Idaho Natl Lab, POB 1625, Idaho Falls, ID 83415 USA. EM r.herbst@inl.gov NR 8 TC 4 Z9 4 U1 1 U2 6 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2557 EP 2571 DI 10.1080/01496390802148662 PG 15 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900021 ER PT J AU Antonio, MR Chiarizia, R Gannaz, B Berthon, L Zorz, N Hill, C Cote, G AF Antonio, M. R. Chiarizia, R. Gannaz, B. Berthon, L. Zorz, N. Hill, C. Cote, G. TI Aggregation in solvent extraction systems containing a malonamide, a dialkylphosphoric acid and their mixtures SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE Am and Eu extraction; aggregation; dialkylphosphoric acids; malonamide; supra-molecular chemistry ID ELECTROSPRAY MASS-SPECTROMETRY; ADVANCED PHOTON SOURCE; 3RD PHASE-FORMATION; TRIVALENT LANTHANIDE; 2-ETHYLHEXANAL OXIME; SURFACE-ADHESION; HARD-SPHERES; N-OCTANE; ESI-MS; TBP AB Aggregation phenomena in n-alkane solutions of di-n-hexylphosphoric acid (HDHP), N,N '-dimethyl-N,N '-dioctylhexylethoxymalonamide (DMDOHEMA), and their mixtures, were investigated by electrospray ionization-mass spectrometry (ESI-MS), vapor pressure osmometry (VPO), and small-angle X-ray and neutron scattering (SAXS and SANS). The objective of the study was to probe the formation of mixed HDHP-DMDOHEMA species before and after extraction of trivalent lanthanide and actinide (M(3+)) nitrates. The most important species formed by HDHP upon metal extraction has the composition M(DHP)(3)(HDHP)(3)(H(2)O). These species exist as spherical aggregates of the reverse micelle type with a polar core diameter of similar to 7 angstrom and total diameter of similar to 11 to similar to 15 angstrom. The aggregation of DMDOHEMA is a progressive phenomenon, with an average aggregation number of similar to 2 in the 0.2 to 0.6M range and larger aggregates forming at higher concentrations. The metal loaded DMDOHEMA aggregates can be considered as interacting spheres with a polar core diameter between similar to 11 and similar to 16 angstrom, depending on composition, a total diameter of up to similar to 25 angstrom, and a weight-average aggregation number of similar to 9. The results obtained in this work provide strong evidence for the formation of mixed aggregates when mixtures of HDHP and DMDOHEMA are used for the extraction of trivalent Ln and An cations. These mixed reverse micelles have a diameter between 19 and 24 angstrom with a polar core diameter of 10 and to 14 angstrom. The most recurrent micellar composition is 2 HDHP and either 4 or 5 DMDOHEMA molecules. C1 [Antonio, M. R.; Chiarizia, R.] Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. [Gannaz, B.; Berthon, L.; Zorz, N.; Hill, C.] DEN VRH DRCP SCPS LCSE, CEA Valrho, Bagnols Sur Ceze, France. [Cote, G.] Univ Paris 06, ENSCP, Paris, France. RP Chiarizia, R (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM chiarizia@anl.gov RI BERTHON, Laurence/B-1374-2016; OI BERTHON, Laurence/0000-0003-3474-8474; Antonio, Mark/0000-0002-1208-4534 NR 37 TC 34 Z9 34 U1 2 U2 32 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2572 EP 2605 DI 10.1080/01496390802121537 PG 34 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900022 ER PT J AU Paulenova, A Alyapyshev, MY Babain, VA Herbst, RS Law, JD AF Paulenova, A. Alyapyshev, M. Yu. Babain, V. A. Herbst, R. S. Law, J. D. TI Extraction of lanthanides with diamides of dipicolinic acid from nitric acid solutions. I SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE americium; dipicolinic; diamides; extraction; lanthanides ID NUCLEAR WASTE SOLUTIONS; SOLVENT-EXTRACTION; SUBSTITUTED MALONAMIDES; ACTINIDES; DIGLYCOLAMIDE; IONS; AM(III); TODGA AB Three ortho-, meta-, and para-derivates of ethyl(tolyl)diamides of dipicolinic acid were synthesized and tested on their extraction performance from nitric acids solutions. Extraction of americium and lanthanides (Ln) by these compounds as a function of nitric acid concentration was studied. Distribution ratios of studied metals were determined using ICP-OES method and radiotracer (241)Am. Am/Ln separation differs among studied diamides, and the best separation was found for N,N '-diethyl-N,N '-di(ortho)tolyl-diamide. C1 [Paulenova, A.] Oregon State Univ, Ctr Radiat, Corvallis, OR 97331 USA. [Alyapyshev, M. Yu.; Babain, V. A.] VG Khlopin Radium Inst, St Petersburg 197022, Russia. [Herbst, R. S.; Law, J. D.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Paulenova, A (reprint author), Oregon State Univ, Ctr Radiat, Corvallis, OR 97331 USA. EM alena.paulenova@oregonstate.edu OI Law, Jack/0000-0001-7085-7542 NR 29 TC 26 Z9 26 U1 0 U2 15 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2606 EP 2618 DI 10.1080/01496390802121636 PG 13 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900023 ER PT J AU Kyser, EA Crowder, ML Carlisle, SB AF Kyser, E. A. Crowder, M. L. Carlisle, S. B. TI Production of neptunium oxide from impure solutions by anion exchange followed by oxalate precipitation SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE anion exchange; neptunium; plutonium; precipitation; purification; uranium AB The stabilization of the neptunium solutions stored at the Savannah River Site (SRS) has generated additional recycle solutions that contain a different mix of impurities. A list of expected purities and the known laboratory and production data for purification from those impurities has been accumulated. An evaluation has been performed of the options for modifying the current process to ensure oxide product purity does not significantly change when recycle solutions are processed. This paper discusses the details of the reduction of the major impurities utilizing both known production quality analyses and laboratory flowsheet development data and proposes modifications to the anion wash volumes to remove higher levels of each impurity. C1 [Kyser, E. A.; Crowder, M. L.] Actinide & Chem Technol Sect, Savannah River Natl Lab, Aiken, SC 29808 USA. [Carlisle, S. B.] HB Line Engn, Aiken, SC USA. RP Kyser, EA (reprint author), Actinide & Chem Technol Sect, Savannah River Natl Lab, 773 A, Aiken, SC 29808 USA. EM eddie.kyser@srnl.doe.gov NR 6 TC 1 Z9 1 U1 1 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2658 EP 2669 DI 10.1080/01496390802119622 PG 12 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900027 ER PT J AU Vaden, D AF Vaden, DeeEarl TI Fuel Conditioning Facility electrorefiner model predictions versus measurements SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE electrochemical processing; electrorefiner; process modeling AB Electrometallurgical treatment of spent nuclear fuel is performed in the Fuel Conditioning Facility (FCF) at the Idaho National Laboratory (INL) by electrochemically separating uranium from the fission products and structural materials in a vessel called an electrorefiner (ER). To continue processing without waiting for sample analyses to assess process conditions, an ER process model predicts the composition of the ER inventory and effluent streams via multi-component, multi-phase chemical equilibrium for chemical reactions and a numerical solution to differential equations for electro-chemical transport. The results of the process model were compared to the electrorefiner measured data. C1 Idaho Natl Lab, Fuel Cycle Programs Div, Idaho Falls, ID 83415 USA. RP Vaden, D (reprint author), Idaho Natl Lab, Fuel Cycle Programs Div, POB 1625, Idaho Falls, ID 83415 USA. EM dee.vaden@inl.gov NR 5 TC 1 Z9 1 U1 0 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2684 EP 2694 DI 10.1080/01496390802122147 PG 11 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900029 ER PT J AU Westphal, BR Park, JJ Shin, JM Park, GI Bateman, KJ Wahlquist, DL AF Westphal, B. R. Park, J. J. Shin, J. M. Park, G. I. Bateman, K. J. Wahlquist, D. L. TI Selective trapping of volatile fission products with an off-gas treatment system SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE fission products; off-gas collection; volatile ID FUELS AB An off-gas treatment system is being developed for the collection of volatile fission products during a head-end processing step. The head-end processing step employs high temperatures to oxidize UO(2) to U(3)O(8) resulting in the separation of fuel from cladding and the removal of volatile fission products. Three volatile fission products have been targeted for trapping on distinct zones of the off-gas system and within those zones, on individual filters. A description of the filter media and a basis for its selection will be given along with the collection mechanisms and design considerations. Results from testing with the off-gas treatment system will also be presented. C1 [Westphal, B. R.; Bateman, K. J.; Wahlquist, D. L.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. [Park, J. J.; Shin, J. M.; Park, G. I.] Korea Atom Energy Res Inst, Taejon, South Korea. RP Westphal, BR (reprint author), Idaho Natl Lab, POB 1625, Idaho Falls, ID 83415 USA. EM brain.westphal@inl.gov OI Wahlquist, Dennis/0000-0001-5182-5078 NR 22 TC 4 Z9 4 U1 1 U2 5 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2695 EP 2708 DI 10.1080/01496390802122139 PG 14 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900030 ER PT J AU Sachdev, P Simpson, MF Frank, SM Yano, K Utgikar, V AF Sachdev, P. Simpson, M. F. Frank, S. M. Yano, K. Utgikar, V. TI Selective separation of Cs and Sr from LiCl-based salt for electrochemical processing of oxide spent nuclear fuel SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE Cs and Sr removal; electrochemical processing; pyroprocessing; spent nuclear fuel treatment; zeolite LiCl salt ion exchange ID ZEOLITE 4A SYSTEM; ION-EXCHANGE; ELECTROLYTIC REDUCTION; EQUILIBRIUM-MODEL; MOLTEN-SALT; CHLORIDE; OCCLUSION; CATIONS AB Electrochemical processing technology is currently being used for the treatment of metallic spent fuel from the Experimental Breeder Reactor-II at Idaho National Laboratory. The treatment of oxide-based spent nuclear fuel via electrochemical processing is possible provided there is a front-end oxide reduction step. During this reduction process, certain fission products, including Cs and Sr, partition into the salt phase and form chlorides. Both solid state and molten LiCl-zeolite-A ion exchange tests were conducted for selectively removing Cs and Sr from LiCl-based salt. The solid-state tests produced in excess of 99% removal of Cs and Sr. The molten state tests failed due to phase transformation of the zeolite structure when in contact with the molten LiCl salt. C1 [Sachdev, P.; Simpson, M. F.; Frank, S. M.] Idaho Natl Lab, Fuel Cycle Programs Div, Idaho Falls, ID 83415 USA. [Yano, K.] Tokai Res & Dev Ctr, Japan Atom Energy Agcy, Naka Ku, Ibaraki, Japan. [Utgikar, V.] Univ Idaho, Idaho Falls, ID USA. RP Sachdev, P (reprint author), Idaho Natl Lab, Fuel Cycle Programs Div, POB 1625, Idaho Falls, ID 83415 USA. EM Prateek.Sachdev@inl.gov RI Frank, Steven/B-9046-2017 OI Frank, Steven/0000-0001-8259-6722 NR 18 TC 2 Z9 2 U1 1 U2 7 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2709 EP 2721 DI 10.1080/01496390802122212 PG 13 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900031 ER PT J AU Bateman, KJ Solbrig, CW AF Bateman, Kenneth J. Solbrig, Charles W. TI Stabilizing glass bonded waste forms containing fission products separated from spent nuclear fuel SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE casting; ceramics; electrorefining; fission products; nuclear waste; pyroprocessing; thermal stress AB A model has been developed to represent the stresses developed when a molten, glass-bonded brittle cylinder (used to store nuclear material) is cooled from high temperature to working temperature. Large diameter solid cylinders are formed by heating glass or glass-bonded mixtures (mixed with nuclear waste) to high temperature (915 degrees C). These cylinders must be cooled as the final step in preparing them for storage. Fast cooling time is desirable for production; however, if cooling is too fast, the cylinder can crack into many pieces. To demonstrate the capability of the model, cooling rate cracking data were obtained on small diameter (7.8 cm diameter) glass-only cylinders. The model and experimental data were combined to determine the critical cooling rate which separates the non-cracking stable glass region from the cracked, non-stable glass regime. Although the data have been obtained so far only on small glass-only cylinders, the data and model were used to extrapolate the critical-cooling rates for large diameter ceramic waste form (CWF) cylinders. The extrapolation estimates long term cooling requirements. While a 52-cm diameter cylinder (EBR-II-waste size) can be cooled to 100 degrees C in 70 hours without cracking, a 181.5-cm diameter cylinder (LWR waste size) requires 35 days to cool to 100 degrees C. These cooling times are long enough that verification of these estimates are required so additional experiments are planned on both glass only and CWF material. C1 [Bateman, Kenneth J.; Solbrig, Charles W.] Idaho Natl Lab, Fuel Cycle Programs Div, Idaho Falls, ID 83415 USA. RP Solbrig, CW (reprint author), Idaho Natl Lab, Fuel Cycle Programs Div, POB 1625, Idaho Falls, ID 83415 USA. EM charles.solbrig@inl.gov NR 17 TC 1 Z9 1 U1 0 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2722 EP 2746 DI 10.1080/01496390802151831 PG 25 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900032 ER PT J AU Rudisill, TS Crowder, ML Bronikowski, MG AF Rudisill, Tracy S. Crowder, Mark L. Bronikowski, Michael G. TI Dissolution of plutonium metal using nitric acid solutions containing potassium fluoride SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE dissolution; nitric acid; plutonium metal AB The deinventory and deactivation of the Department of Energy's (DOE's) FB-Line facility at the Savannah River Site (SRS) required the disposition of approximately 2000 items from the facility's vaults. Plutonium (Pu) scraps and residues which do not meet criteria for conversion to a mixed oxide fuel will be dissolved and the solution stored for subsequent disposition. Some of the items scheduled for dissolution are composite materials containing Pu and tantalum (Ta) metals. The preferred approach for handling this material is to dissolve the Pu metal, rinse the Ta metal with water to remove residual acid, and burn the Ta metal. The use of a 4 M nitric acid (HNO(3)) solution containing 0.2 M potassium fluoride (KF) was initially recommended for the dissolution of approximately 500 g of Pu metal. However, prior to the use of the flowsheet in the SRS facility, a new processing plan was proposed in which the feed to the dissolver could contain up to 1250 g of Pu metal. To evaluate the use of a larger batch size and subsequent issues associated with the precipitation of plutonium-containing solids from the dissolving solution, scaled experiments were performed using Pu metal and samples of the composite material. In the initial experiment, incomplete dissolution of a Pu metal sample demonstrated that a 1250 g batch size was not feasible in the HB-Line dissolver. Approximately 45% of the Pu was solubilized in 4h. The remaining Pu metal was converted to plutonium oxide (PuO(2)). Based on this work, the dissolution of 500 g of Pu metal using a 4-6 h cycle time was recommended for the HB-Line facility. Three dissolution experiments were subsequently performed using samples of the Pu/Ta composite material to demonstrate conditions which reduced the risk of precipitating a double fluoride salt containing Pu and K from the dissolving solution. In these experiments, the KF concentration was reduced from 0.2 M to either 0.15 or 0.175 M. With the use of 4 M HNO(3) and a reduction in the KF concentration to 0.175 M, the dissolution of 300 g of Pu metal is expected to be essentially complete in 6h. The dissolution of larger batch sizes would result in the formation of PuO(2) solids. Incomplete dissolution of the PuO(2) formed from the metal is not a solubility limitation, but can be attributed to a combination of reduced acidity and complexation of fluoride which slows the dissolution kinetics and effectively limits the mass of Pu dissolved. C1 [Rudisill, Tracy S.; Crowder, Mark L.; Bronikowski, Michael G.] Savannah River Natl Lab, Aiken, SC 29808 USA. RP Rudisill, TS (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. EM tracy.rudisill@srnl.doe.gov RI Johnson, Marilyn/E-7209-2011 NR 10 TC 0 Z9 0 U1 2 U2 3 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2747 EP 2761 DI 10.1080/01496390802151567 PG 15 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900033 ER PT J AU Crowder, ML Rudisill, TS Laurinat, JE Mickalonis, JI AF Crowder, Mark L. Rudisill, Tracy S. Laurinat, James E. Mickalonis, John I. TI Evaluation of proposed flowsheet changes for the highly enriched uranium Blenddown program SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE boron; corrosion; fluoride complexation; solvent extraction; uranium AB At the Savannah River Site, highly enriched uranium (HEU) is dissolved, purified, and blended with natural uranium to make low enriched uranium solutions sufficiently pure for conversion to power reactor fuel. The process to dissolve and purify aluminum-clad HEU fuel at SRS is well-established. However, for the dissolution and recovery of metal scrap, flowsheet changes were proposed. This study evaluates the proposed changes. Specifically, solvent extraction modeling calculations were performed which indicated that one solvent extraction cycle would be sufficient to purify the metal scrap solution by removing boron, which is added as a neutron poison. In addition, stability constants from the literature and Savannah River National Laboratory corrosion studies were documented to demonstrate that boron complexation of fluoride in nitric acid solutions, at the levels anticipated, is sufficient to prevent excessive corrosion in stainless steel vessels. Downstream from the purification process, limitations on the boron concentration in waste evaporators were recommended to prevent formation of boron-containing solids. C1 [Crowder, Mark L.; Rudisill, Tracy S.; Laurinat, James E.; Mickalonis, John I.] Savannah River Natl Lab, Aiken, SC 29808 USA. RP Crowder, ML (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. EM mark.crowder@srnl.doe.gov NR 11 TC 0 Z9 0 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2762 EP 2774 DI 10.1080/01496390802121867 PG 13 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900034 ER PT J AU Visser, AE Pierce, RA Laurinat, JE AF Visser, A. E. Pierce, R. A. Laurinat, J. E. TI Purification of uranium from a uranium/molybdenum alloy SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE distribution; molybdenum; solubility; solvent extraction; uranium AB The Savannah River Site will recycle a nuclear fuel comprised of 90% uranium-10% molybdenum by weight. The process flowsheet calls for dissolution of the material in nitric acid to a uranium concentration of 15-20 g/L without the formation of precipitates. The dissolution will be followed by separation of uranium from molybdenum using solvent extraction with 7.5 vol% tributylphosphate in n-paraffin. Testing with the fuel validated dissolution and solubility data reported in the literature. Batch distribution coefficient measurements were performed for the extraction, strip, and wash stages with particular focus on the distribution of molybdenum. C1 [Visser, A. E.; Pierce, R. A.; Laurinat, J. E.] Savannah River Natl Lab, Aiken, SC 29808 USA. RP Pierce, RA (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. EM robert.pierce@srnl.doe.gov NR 12 TC 0 Z9 0 U1 3 U2 7 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2775 EP 2785 DI 10.1080/01496390802121701 PG 11 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900035 ER PT J AU Poirier, MR Peters, TB Brass, EA Brown, SJ Geeting, MW Johnson, LC Coleman, CJ Crump, SL Barnes, MJ Fink, SD AF Poirier, M. R. Peters, T. B. Brass, E. A. Brown, S. J. Geeting, M. W. Johnson, L. C., Jr. Coleman, C. J. Crump, S. L. Barnes, M. J. Fink, S. D. TI Full-scale testing of a Caustic Side Solvent Extraction system to remove cesium from Savannah River Site radioactive waste SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN ID HIGH-LEVEL WASTE AB Savannah River Site (SRS) personnel have completed construction and assembly of the Modular Caustic Side Solvent Extraction Unit (MCU) facility. Following assembly, they conducted testing to evaluate the ability of the process to remove non-radioactive cesium and to separate the aqueous and organic phases. They conducted tests at salt solution flow rates of 3.5, 6.0, and 8.5 gpm. During testing, the MCU Facility collected samples and submitted them to Savannah River National Laboratory (SRNL) personnel for analysis of cesium, Isopar (R) L, and modifier [1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol]. SRNL personnel analyzed the aqueous samples for cesium by Inductively-Coupled Plasma Mass Spectroscopy (ICP-MS) and the solvent samples for cesium using a Parr Bomb digestion followed by ICP-MS. They analyzed aqueous samples for Isopar (R) L and modifier by gas chromatography (GC). The conclusions from the cesium analyses follow. The cesium in the feed samples measured 15.8 mg/L, in agreement with expectations. The decontamination factor measured 181-1580 at a salt solution flow rate of 3.5 gpm, 211-252 at a salt solution flow rate of 6.0 gpm, and 275-878 at a salt solution flow rate of 8.5 gpm. The concentration factor measured 11.0-11.1 at 3.5 gpm salt solution flow rate, 12.8-13.2 at 6.0 gpm salt solution flow rate, and 12.0-13.2 at 8.5 gpm salt solution flow rate. The organic carryover from the final extraction contactor (#7) varied between 22 and 710 mg/L Isopar (R) L. The organic carryover was less at the lowest flow rate. The organic carryover from the final strip contactor (#7) varied between 80 and 180 mg/L Isopar (R) L. The organic carryover in the Decontaminated Salt Solution Hold Tank (DSSHT) and the Strip Effluent Hold Tank (SEHT) was less than 10 mg/L Isopar (R) L, indicating good recovery of the solvent by the coalescers and decanters. C1 [Poirier, M. R.; Peters, T. B.; Johnson, L. C., Jr.; Coleman, C. J.; Crump, S. L.; Barnes, M. J.; Fink, S. D.] Savannah River Natl Lab, Aiken, SC 29808 USA. [Brass, E. A.; Brown, S. J.; Geeting, M. W.] Washington Savannah River Co, Alken, SC USA. RP Poirier, MR (reprint author), Savannah River Natl Lab, Aiken, SC 29808 USA. EM Michael.Poirier@sml.doe.gov NR 6 TC 2 Z9 2 U1 0 U2 3 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2797 EP 2813 DI 10.1080/01496390802148720 PG 17 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900037 ER PT J AU Fondeur, FF Walker, DD Fink, SD AF Fondeur, F. F. Walker, D. D. Fink, S. D. TI Volatility rate of Isopar (R) L, benzene, salt solution, potassium tetraphenyl borate (KTPB), and their mixtures by ASTM method E 2008-04 SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE evaporatin; gas diffusion; immiscible; TGA AB Data are provided for the relative rate of volatility of Isopar (R) L, CSSX solvent, and salt solution in relation to benzene. The results also include rates for mixtures of the various species and the impact of tetraphenylborate on the volatility. The results are consistent with the expected behavior in that the component with a lower boiling point volatizes faster than a component with a higher boiling point. Fick's diffusion law explained the data well and it predicted the diffusivity of Isopar (R) L (a mixture of hydrocarbons) intermediate temperatures between 35 and 70 degrees C. Inspection of the data shows the volatility of Isopar (R) L is approximately 1/10th that of the salt solution and approximately 1/100th that of benzene under comparable conditions at the temperatures studied. The results can be used to rank the relative volatility rate of these substances. C1 [Fondeur, F. F.; Fink, S. D.] Washington Savannah River Co, Savannah River Lab, Aiken, SC 29080 USA. RP Fondeur, FF (reprint author), Washington Savannah River Co, Savannah River Lab, Aiken, SC 29080 USA. EM fernando.fondeur@srs.gov NR 14 TC 0 Z9 0 U1 1 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2814 EP 2825 DI 10.1080/01496390802151955 PG 12 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900038 ER PT J AU Fondeur, FF Hobbs, DT Fink, SD AF Fondeur, F. F. Hobbs, D. T. Fink, S. D. TI Thermal and spectroscopic analyses of Caustic Side Solvent Extraction solvent contacted with 16 molar and 8 molar nitric acid SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE ARC; energetic; infrared; nitration ID NITRATION AB Thermal and spectroscopic analyses were performed on multiple layers formed when Caustic Side Solvent Extraction (CSSX) solvent was contacted with 16 M or 8 M nitric acid. A rapid (i.e., minutes to hours) chemical reaction occurs between the solvent and 16 M or 8 M nitric acid as evidenced by color changes and the detection of nitro groups in the infrared spectrum of the aged samples. Thermal analysis revealed that decomposition of the resulting mixture does not meet the definition of explosive or deflagrating material. C1 [Fondeur, F. F.] Washington Savannah River Co, Savannah River Lab, Aiken, SC 29808 USA. RP Fondeur, FF (reprint author), Washington Savannah River Co, Savannah River Lab, Bldg 773-A,B-124, Aiken, SC 29808 USA. EM fernando.fondeur@srs.gov NR 15 TC 1 Z9 1 U1 0 U2 0 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2826 EP 2839 DI 10.1080/01496390802151971 PG 14 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900039 ER PT J AU Rapko, BM Lumetta, GJ Deschane, JR Peterson, RA AF Rapko, B. M. Lumetta, G. J. Deschane, J. R. Peterson, R. A. TI Process development for permanganate addition during oxidative leaching of Hanford tank sludge simulants SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE chromium; chromium hydroxide; chromium oxide; oxidative leaching; oxyhydroxide; permanganate ID CHROMIUM; MANGANESE AB In previous studies, we have examined using sodium permanganate for selectively oxidizing and removing chromium from washed Hanford tank sludges. The conclusion from the previous work was that contact with sodium permanganate in a minimally caustic solution, i.e., 0.1 to 0.25 M [OH(-)] initially, provided maximum Cr dissolution while minimizing concomitant Pu dissolution. This report describes work focused on developing simulants to be used in pilot scale oxidative leaching tests; developing methods for monitoring chromium oxidation by permanganate; and identifying the Cr and Mn materials formed during the oxidative leaching process. The impact of such variables as the Cr compound used, agitation rate, temperature, hydroxide concentration, and initial MnO(4)(-):Cr ratio on the rate and extent of chromate formation were examined. C1 [Rapko, B. M.; Lumetta, G. J.; Deschane, J. R.; Peterson, R. A.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Rapko, BM (reprint author), Pacific NW Natl Lab, POB 999,Battelle Blvd, Richland, WA 99352 USA. EM brian.rapko@pnl.gov OI Peterson, Reid/0000-0003-3368-1896 NR 16 TC 1 Z9 1 U1 0 U2 1 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2840 EP 2858 DI 10.1080/01496390802121834 PG 19 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900040 ER PT J AU White, TL Stone, ME Calloway, TB Brigmon, RL Eibling, RE Nikolov, A Wasan, D AF White, T. L. Stone, M. E. Calloway, T. B. Brigmon, R. L. Eibling, R. E. Nikolov, A. Wasan, D. TI Understanding the effects of dispersant addition to slurry rheology using laser scanning confocal microscopy SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE dispersants; laser scanning confocal microscopy; slurry rheology ID COMPOSITE FILMS; SUSPENSIONS AB The effectiveness of three dispersants to modify slurry rheology was examined using rheology measurements and laser scanning confocal microscopy (LSCM) in simulated waste solutions. All of the dispersants lowered the yield stress of the slurries below the baseline samples. The rheology curves were fitted reasonably to a Bingham Plastic model. The three-dimensional LSCM images of simulants showed distinct aggregates were greatly reduced after the addition of dispersants leading to a lowering of the yield stress of the simulated waste slurry solutions. C1 [White, T. L.; Stone, M. E.; Calloway, T. B.; Brigmon, R. L.; Eibling, R. E.] Washington Savannah River Co, Savannah River Natl Lab, Aiken, SC 29808 USA. [Nikolov, A.; Wasan, D.] IIT, Chicago, IL 60616 USA. RP White, TL (reprint author), Washington Savannah River Co, Savannah River Natl Lab, 773-A,B-160, Aiken, SC 29808 USA. EM thomas02.white@srnl.doe.gov NR 11 TC 1 Z9 1 U1 0 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2859 EP 2871 DI 10.1080/01496390802152516 PG 13 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900041 ER PT J AU Snow, LA Lumetta, GJ Fiskum, S Peterson, RA AF Snow, L. A. Lumetta, G. J. Fiskum, S. Peterson, R. A. TI Boehmite actual waste dissolution studies SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE boehmite; Hanford; HLW; plant; tank waste; waste treatment ID GIBBSITE; RATES AB The U.S. Department of Energy plans to vitrify approximately 60,000 metric tons of high-level waste (HLW) sludge from underground storage tanks at the Hanford Nuclear Reservation. To reduce the volume of HLW requiring treatment, a goal has been set to remove a significant quantity of the aluminum, which comprises nearly 70 percent of the sludge. Aluminum is found in the form of gibbsite, sodium aluminate and boehmite. Gibbsite and sodium aluminate can be easily dissolved by washing the waste stream with caustic. Boehmite, which comprises nearly half of the total aluminum, is more resistant to caustic dissolution and requires higher treatment temperatures and hydroxide concentrations. Samples were taken from four Hanford tanks and homogenized in order to give a sample that is representative of REDOX (Reduction Oxidation process for Pu recovery) sludge solids. Bench scale testing was performed on the homogenized waste to study the dissolution of boehmite. Dissolution was studied at three different hydroxide concentrations, with each concentration being run at three different temperatures. Samples were taken periodically over the 170 hour runs in order to determine leaching kinetics. Results of the dissolution studies and implications for the proposed processing of these wastes will be discussed. C1 [Snow, L. A.; Lumetta, G. J.; Fiskum, S.; Peterson, R. A.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Snow, LA (reprint author), Pacific NW Natl Lab, POB 999,MSIN P7-25, Richland, WA 99352 USA. EM lanee.snow@pnl.gov OI Peterson, Reid/0000-0003-3368-1896 NR 2 TC 1 Z9 1 U1 3 U2 9 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2900 EP 2916 DI 10.1080/01496390802151666 PG 17 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900044 ER PT J AU Oji, LN Fellinger, TL Hobbs, DT Badheka, NP Wilmarth, WR Taylor, M Kamenetsky, EA Islam, M AF Oji, L. N. Fellinger, T. L. Hobbs, D. T. Badheka, N. P. Wilmarth, W. R. Taylor, M. Kamenetsky, E. A. Islam, M. TI Studies of potential inhibitors of sodium aluminosilicate scales in High-Level waste evaporation SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE antiscalant; cancrinite; nuclear waste evaporator; scale inhibitor; sodalite; sodium aluminosilicate ID CANCRINITE; SODALITE AB For a decade, the evaporation of highly alkaline High-Level nuclear wastes as practiced in some DOE nuclear waste facilities has produced sodium aluminosilicate scales causing both operation and criticality hazards. Segregation of aluminum-rich wastes from silicate-rich wastes minimizes the amount of scale produced and reduces cleaning expenses but does not eliminate scaling nor increase operational flexibility in waste processing. Similar issues have affected the aluminum refining industry for many decades. Over the past several years, successful commercial products have been identified to eliminate aluminosilicate fouling in the aluminum industry but have not been utilized in a nuclear environment. Laboratory quantities of three proprietary aluminosilicate scale inhibitors produced by Cytec industries have been shown to prevent formation of aluminosilicate scales. The Savannah River National Laboratory (SRNL) has been actively testing these potential scale inhibitors to examine their radiation stability, radiolytic degradation behaviors, and downstream impacts to determine their viability within the High-Level nuclear waste system at the Savannah River Site (SRS). One of the tested polymers has been found to successfully meet the established criteria for application in the nuclear waste environment. C1 [Oji, L. N.; Fellinger, T. L.; Hobbs, D. T.; Badheka, N. P.; Wilmarth, W. R.] Savannah River Natl Lab, Aiken, SC USA. [Taylor, M.; Kamenetsky, E. A.; Islam, M.] Cytec Ind Inc, Stamford, CT USA. RP Oji, LN (reprint author), Savannah River Natl Lab, POB X, Aiken, SC USA. EM lawrence.oji@srnl.doe.gov NR 16 TC 0 Z9 0 U1 0 U2 4 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2917 EP 2928 DI 10.1080/01496390802121958 PG 12 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900045 ER PT J AU Smith, FG Lee, SY King, WD McCabe, DJ AF Smith, Frank G. Lee, Si Young King, William D. McCabe, Daniel J. TI Comparisons of crystalline silicotitanate and resorcinol formaldehyde media for cesium removal by in-tank column processing SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE CST; IE-911; ion exchange; modeling; RF; thermal analysis AB Chemical and thermal performance of crystalline silicotitanate (CST) and resorcinol-formaldehyde (RF) ion exchange columns are modeled for configurations that fit inside Savannah River Site waste tanks. Good cesium removal is predicted for both media. More waste can be processed per cycle with CST. Unlike RF, CST is not elutable and requires lead column replacement after each cycle. RF is subject to chemical and radiolytic damage reducing capacity each cycle. Fast cesium loading kinetics for RF allows minimization of exposure. Modeling shows that the baseline cooling system provides adequate cooling to maintain columns within process limits and indicates that removal of the outer cooling jackets may be possible. C1 [Smith, Frank G.; Lee, Si Young; King, William D.; McCabe, Daniel J.] Washington Savannah River Co, Savannah River Natl Lab, Aiken, SC 29808 USA. RP King, WD (reprint author), Washington Savannah River Co, Savannah River Natl Lab, Aiken, SC 29808 USA. EM william02.king@srnl.doe.gov NR 20 TC 7 Z9 7 U1 2 U2 7 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 0149-6395 EI 1520-5754 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2929 EP 2942 DI 10.1080/01496390802119382 PG 14 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900046 ER PT J AU Duignan, MR Nash, CA Punch, TM AF Duignan, Mark R. Nash, Charles A. Punch, Timothy M. TI High aspect ratio ion exchange resin bed - Hydraulic results for spherical resin beads SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 15th Symposium on Separation Science and Technology for Energy Applications CY OCT 21-25, 2007 CL Gatlinburg, TN DE cesium removal; formaldehyde; resorcinol; small column ion exchange; spherical resin AB A principal role of the DOE Savannah River Site is to safely dispose of a large volume of liquid nuclear waste held in many storage tanks. An in-tank ion exchange unit is being considered for cesium removal to accelerate waste processing. This unit is planned to have a relatively high bed height to diameter ratio (10:1). Complicating the design is the need to cool the ion exchange media; therefore, the ion exchange column will have a central cooling core making the flow path annular. To separate cesium from waste the media being considered is made of resorcinol formaldehyde resin deposited on spherical plastic beads and is a substitute for a previously tested resin made of crystalline silicotitanate. This spherical media not only has an advantage of being mechanically robust, but, unlike its predecessor, it is also reusable, that is, loaded cesium can be removed through elution and regeneration. Resin regeneration leads to more efficient operation and less spent resin waste, but its hydraulic performance in the planned ion exchange column was unknown. Moreover, the recycling process of this spherical resorcinol formaldehyde causes its volume to significantly shrink and swell. To determine the spherical media's hydraulic demand a linearly scaled column was designed and tested. The waste simulant used was prototypic of the wastes' viscosity and density. This paper discusses the hydraulic performance of the media that will be used to assist in the design of a full-scale unit. C1 [Duignan, Mark R.; Nash, Charles A.; Punch, Timothy M.] Savannah River Natl Lab, Aiken, SC 29080 USA. RP Duignan, MR (reprint author), Savannah River Natl Lab, Aiken, SC 29080 USA. EM mark.duignan@srnl.doe.gov NR 13 TC 7 Z9 7 U1 2 U2 5 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 9-10 BP 2943 EP 2979 DI 10.1080/01496390802119051 PG 37 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 335BX UT WOS:000258266900047 ER PT J AU Powell, BA Rao, LF Nash, KL AF Powell, Brian A. Rao, Linfeng Nash, Kenneth. L. TI Examination of Uranium(VI) Leaching during Ligand Promoted Dissolution of Waste Tank Sludge Surrogates SO SEPARATION SCIENCE AND TECHNOLOGY LA English DT Article DE Actimide; boehmite; Hanford; HEDPA; sludge; tank waste; uranium ID IONIC-STRENGTH; CHELATING-AGENTS; ADSORPTION; PHOSPHATE; ALUMINA; PH; COMPLEXATION; GOETHITE; SORPTION; AL(III) AB The dissolution of synthetic boehmite (gamma-AlOOH) by 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) was examined in a series of batch adsorption/dissolution experiments. Additionally, the leaching behavior of (233)U(VI) from boehmite was examined as a function of pH and HEDPA concentration. The results are discussed in terms of sludge washing procedures that may be utilized during underground tank waste remediation. In the pH range 4 to 10, complexation of Al(III) by HEDPA significantly enhanced dissolution of boehmite. This phenomenon was especially pronounced in the neutral pH region where the solubility of aluminum, in the absence of complexants, is limited by the formation of sparsely soluble aluminum hydroxides. At pH higher than 10, the dissolution of synthetic boehmite was inhibited by HEDPA, likely due to sorption of Al(III):HEDPA complexes. The addition of HEDPA to equilibrated U(VI)-synthetic boehmite suspensions yielded an increase in the aqueous phase uranium concentration. Partitioning of uranium between the solid and aqueous phase is described in terms of U(VI):HEDPA speciation and dissolution of the boehmite solid phase. C1 [Powell, Brian A.; Rao, Linfeng] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. [Nash, Kenneth. L.] Washington State Univ, Pullman, WA 99164 USA. RP Powell, BA (reprint author), Clemson Univ, Dept Environm Engn & Earth Sci, Anderson, SC 29625 USA. EM bpowell@clemson.edu RI Powell, Brian /C-7640-2011 OI Powell, Brian /0000-0003-0423-0180 FU U. S. Department of Energy [DE-AC02-05CH11231] FX This work was supported by the Director, Office of Science, Office of Biological and Environmental Research of the U. S. Department of Energy under Contract No. DE-AC02-05CH11231 at the Lawrence Berkeley National Laboratory. NR 22 TC 0 Z9 0 U1 1 U2 7 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-6395 J9 SEP SCI TECHNOL JI Sep. Sci. Technol. PY 2008 VL 43 IS 15 BP 3798 EP 3812 DI 10.1080/01496390802365795 PG 15 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA 362PR UT WOS:000260210100002 ER PT S AU Collins, MJ Mitchell, S AF Collins, Michael J. Mitchell, Scott BE Golomb, SW Parker, MG Pott, A Winterhof, A TI Distance-Avoiding Sequences for Extremely Low-Bandwidth Authentication SO SEQUENCES AND THEIR APPLICATIONS - SETA 2008 SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Proceedings Paper CT 5th International Conference on Sequences and Their Applications (SETA 2008) CY SEP 14-18, 2008 CL Lexington, KY SP Univ Kentucky Coll Engn AB We develop a scheme for providing strong cryptographic authentication on a stream of messages which consumes very little bandwidth (as little as one bit per message) and is robust in the presence of dropped messages. Such a scheme should be useful for extremely low-power, low-bandwidth wireless sensor networks and "smart dust" applications. The. tradeoffs among security, memory, bandwidth, and tolerance for missing messages give rise to several new optimization problems. We report on experimental results and derive bounds on the performance of the scheme. C1 [Collins, Michael J.; Mitchell, Scott] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Collins, MJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 978-3-540-85911-6 J9 LECT NOTES COMPUT SC PY 2008 VL 5203 BP 230 EP 238 PG 9 WC Computer Science, Theory & Methods SC Computer Science GA BIM21 UT WOS:000260673100021 ER PT B AU Sakellaridi, S Fang, HR Saad, Y AF Sakellaridi, Sophia Fang, Haw-ren Saad, Yousef BE Wani, MA Chen, X Casasent, D Kurgan, L Hu, T Hafeez, K TI Graph-based Multilevel Dimensionality Reduction with Applications to Eigenfaces and Latent Semantic Indexing SO SEVENTH INTERNATIONAL CONFERENCE ON MACHINE LEARNING AND APPLICATIONS, PROCEEDINGS LA English DT Proceedings Paper CT 7th International Conference on Machine Learning and Applications CY DEC 11-13, 2008 CL San Diego, CA SP IEEE SMC, Calif State Univ, Bakersfield, Assoc Machine Learning & Applicat ID NONNEGATIVE MATRIX FACTORIZATION; LOW-RANK APPROXIMATIONS; FACE REPRESENTATION; COMPONENT ANALYSIS; RECOGNITION; RETRIEVAL AB Dimension reduction techniques have been successfully applied to face recognition and text information retrieval. The process can be time-consuming when the data set is large. This paper presents a multilevel framework to reduce the size of the data set, prior to performing dimension reduction. The algorithm exploits nearest-neighbor graphs. It recursively coarsens the data by finding a maximal matching level by level. The coarsened data at the lowest level is then projected using a known linear dimensionality reduction method. The same linear mapping is performed on the original data set, and on any new test data. The methods are illustrated on two applications: Eigenfaces (face recognition) and Latent Semantic Indexing (text mining). Experimental results indicate that the multilevel techniques proposed here offer a very appealing cost to quality ratio. C1 [Sakellaridi, Sophia; Saad, Yousef] Univ Minnesota, Dept Comp Sci & Engn, Minneapolis, MN 55455 USA. [Fang, Haw-ren] Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Sakellaridi, S (reprint author), Univ Minnesota, Dept Comp Sci & Engn, Minneapolis, MN 55455 USA. EM sakell@cs.umn.edu; hrfang@mcs.anl.gov; saad@cs.umn.edu FU NSF [DMS 0510131, DMS 0528492]; Minnesota Supercomputing Institute FX This work was supported by NSF grants DMS 0510131 and DMS 0528492 and by the Minnesota Supercomputing Institute. NR 19 TC 3 Z9 3 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3495-4 PY 2008 BP 194 EP + DI 10.1109/ICMLA.2008.140 PG 3 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIV71 UT WOS:000263205800028 ER PT B AU Fang, HR Saad, Y AF Fang, Haw-ren Saad, Yousef BE Wani, MA Chen, X Casasent, D Kurgan, L Hu, T Hafeez, K TI Farthest Centroid Divisive Clustering SO SEVENTH INTERNATIONAL CONFERENCE ON MACHINE LEARNING AND APPLICATIONS, PROCEEDINGS LA English DT Proceedings Paper CT 7th International Conference on Machine Learning and Applications CY DEC 11-13, 2008 CL San Diego, CA SP IEEE SMC, Calif State Univ, Bakersfield, Assoc Machine Learning & Applicat AB A method is presented to partition a given set of data entries embedded in Euclidean space by recursively bisecting clusters into smaller ones. The initial set is subdivided into two subsets whose centroids are farthest from each other, and the process is repeated recursively on each subset. An approximate algorithm is proposed to solve the original integer programming problem which is NP-hard. Experimental evidence shows that the clustering method often outperforms a standard spectral clustering method, albeit at a slightly higher computational cost. The paper also discusses improvements of the standard K-means algorithm. Specifically, the clustering quality resulting from the K-means technique can be significantly enhanced by using the proposed algorithm for its initialization. C1 [Fang, Haw-ren] Argonne Natl Lab, Math & Comp Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. [Saad, Yousef] Univ Minnesota, Comp Sci & Eng Dept, Minneapolis, MN 55455 USA. RP Fang, HR (reprint author), Argonne Natl Lab, Math & Comp Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. EM hrfang@mcs.anl.gov; saad@cs.umn.edu FU NSF [DMS 0510131, DMS 0528492]; Minnesota Supercomputing Institute FX This work was supported by NSF grants DMS 0510131 and DMS 0528492 and by the Minnesota Supercomputing Institute. NR 16 TC 0 Z9 0 U1 0 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3495-4 PY 2008 BP 232 EP + DI 10.1109/ICMLA.2008.141 PG 2 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIV71 UT WOS:000263205800033 ER PT B AU Ushizima, DM Rubel, O Prabhat Weber, GH Bethel, EW Aragon, CR Geddes, CGR Cormier-Michel, E Hamann, B Messmer, P Hagen, H AF Ushizima, Daniela M. Ruebel, Oliver Prabhat Weber, Gunther H. Bethel, E. Wes Aragon, Cecilia R. Geddes, Cameron G. R. Cormier-Michel, Estelle Hamann, Bernd Messmer, Peter Hagen, Hans BE Wani, MA Chen, X Casasent, D Kurgan, L Hu, T Hafeez, K TI Automated analysis for detecting beams in laser wakefield simulations SO SEVENTH INTERNATIONAL CONFERENCE ON MACHINE LEARNING AND APPLICATIONS, PROCEEDINGS LA English DT Proceedings Paper CT 7th International Conference on Machine Learning and Applications CY DEC 11-13, 2008 CL San Diego, CA SP IEEE SMC, Calif State Univ Bakersfield, Assoc Machine Learning & Applicat AB Laser wakefield particle accelerators have shown the potential to generate electric fields thousands of times higher than those of conventional accelerators. The resulting extremely short particle acceleration distance could yield a potential new compact source of energetic electrons and radiation, with wide applications from medicine to physics. Physicists investigate laser-plasma internal dynamics by running particle-in-cell simulations; however, this generates a large dataset that requires time-consuming, manual inspection by experts in order to detect key features such as beam formation. This paper describes a framework to automate the data analysis and classification of simulation data. First, we propose a new method to identify locations with high density of particles in the space-time domain, based on maximum extremum point detection on the particle distribution. We analyze high density electron regions using a lifetime diagram by organizing and pruning the maximum extrema as nodes in a minimum spanning tree. Second, we partition the multivariate data using fuzzy clustering to detect time steps in a experiment that may contain a high quality electron beam. Finally, we combine results from fuzzy clustering and bunch lifetime analysis to estimate spatially confined beams. We demonstrate our algorithms successfully on four different simulation datasets. C1 [Ushizima, Daniela M.; Ruebel, Oliver; Prabhat; Weber, Gunther H.; Bethel, E. Wes; Aragon, Cecilia R.; Geddes, Cameron G. R.; Cormier-Michel, Estelle; Hamann, Bernd; Messmer, Peter; Hagen, Hans] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ushizima, DM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM dushizima@lbl.gov; oruebel@lbl.gov; prabhat@lbl.gov; ghweber@lbl.gov; ewbethel@lbl.gov; craragon@lbl.gov; cgrgeddes@lbl.gov; emichell@lbl.gov; hamann@cs.ucdavis.edu; messmer@txcorp.com; hagen@infonnatik.uni-kl.de OI Weber, Gunther/0000-0002-1794-1398 NR 14 TC 1 Z9 1 U1 0 U2 10 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3495-4 PY 2008 BP 382 EP 387 DI 10.1109/ICMLA.2008.69 PG 6 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIV71 UT WOS:000263205800055 ER PT B AU Webb-Robertson, BJM Matzke, MM Oehmen, CS AF Webb-Robertson, Bobbie-Jo M. Matzke, Melissa M. Oehmen, Christopher S. BE Wani, MA Chen, X Casasent, D Kurgan, L Hu, T Hafeez, K TI Dimension Reduction via Unsupervised Learning Yields Significant Computational Improvements for Support Vector Machine Based Protein Family Classification SO SEVENTH INTERNATIONAL CONFERENCE ON MACHINE LEARNING AND APPLICATIONS, PROCEEDINGS LA English DT Proceedings Paper CT 7th International Conference on Machine Learning and Applications CY DEC 11-13, 2008 CL San Diego, CA SP IEEE SMC, Calif State Univ, Bakersfield, Assoc Machine Learning & Applicat ID REMOTE HOMOLOGY DETECTION; SEQUENTIAL PROJECTION PURSUIT; EXPLORATORY DATA-ANALYSIS; ALGORITHM; ALIGNMENT; BALSA AB Reducing the dimension of vectors used in training support vector machines (SVMs) results in a proportional speedup in training time. For large-scale problems this can make the difference between tractable and intractable training tasks. However, it is critical that classifiers trained on reduced datasets perform as reliably as their counterparts trained on high-dimensional data. We assessed principal component analysis (PCA) and sequential project pursuit (SPP) as dimension reduction strategies in the biology application of classifying proteins into well-defined functional families' (SVM-based protein family classification) by their impact on run-time, sensitivity and selectivity. Homology vectors of 4352 elements were reduced to approximately 2% of the original data size using PCA and SPP without significantly affecting accuracy, while leading to approximately a 28-fold speedup in run-time. C1 [Webb-Robertson, Bobbie-Jo M.; Matzke, Melissa M.; Oehmen, Christopher S.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Webb-Robertson, BJM (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. EM bj@pnl.gov; melissa_matzke@yahoo.com; christopher.oehmen@pnl.gov NR 23 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3495-4 PY 2008 BP 457 EP 462 DI 10.1109/ICMLA.2008.120 PG 6 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BIV71 UT WOS:000263205800066 ER PT B AU Gorton, I AF Gorton, Ian BE Kruchten, P Garlan, D Woods, E TI Software architecture challenges for data intensive computing SO SEVENTH WORKING IEEE/IFIP CONFERENCE ON SOFTWARE ARCHITECTURE, PROCEEDINGS LA English DT Proceedings Paper CT 7th Working IEEE/IFIP Conference on Software Architecture (WISCA 2008) CY FEB 18-22, 2008 CL Vancouver, CANADA SP IEEE, IFIP AB Data intensive computing is concerned with creating scalable solutions for capturing, analyzing, managing and understanding multi-terabyte and petabyte data volumes. Such data volumes exist in a diverse range of application domains, including scientific research, bioinformatics, cyber security, social computing and commerce. Innovative hardware and software technologies to address these problems must scale to meet these ballooning data volumes and simultaneously reduce the time needed to provide effective data analysis. This paper describes some of the software architecture challenges that must be addressed when building data intensive applications and supporting infrastructures. These revolve around requirements for adaptive resource utilization and management, flexible integration, robustness and scalable data management. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gorton, I (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Gorton, Ian/A-8247-2009 NR 4 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3092-5 PY 2008 BP 4 EP 6 DI 10.1109/WICSA.2008.50 PG 3 WC Computer Science, Software Engineering SC Computer Science GA BHL74 UT WOS:000254145600001 ER PT B AU Gorton, I Wynne, A Almquist, J Chatterton, J AF Gorton, Ian Wynne, Adam Almquist, Justin Chatterton, Jack BE Kruchten, P Garlan, D Woods, E TI The MeDICi integration framework: A platform for high performance data streaming applications SO SEVENTH WORKING IEEE/IFIP CONFERENCE ON SOFTWARE ARCHITECTURE, PROCEEDINGS LA English DT Proceedings Paper CT 7th Working IEEE/IFIP Conference on Software Architecture (WISCA 2008) CY FEB 18-22, 2008 CL Vancouver, CANADA SP IEEE, IFIP AB Building high performance analytical applications for data streams generated from sensors is a challenging software engineering problem. Such applications typically comprise a complex pipeline of processing components that capture, transform and analyze the incoming data stream. In addition, applications must provide high throughput, be scalable and easily modifiable so that new analytical components can be added with minimum effort. In this paper we describe the MeDICi Integration Framework (MIF), which is a middleware platform we have created to address these challenges. The MIF extends an open source messaging platform with a component-based API for integrating components into analytical pipelines. We describe the features and capabilities of the MIF, and show how it has been used to build a production analytical application for detecting cyber security attacks. The application was composed from multiple independently developed components using several different programming languages. The resulting application was able to process network sensor traffic in real time and provide insightful feedback to network analysts as soon as potential attacks were recognized. C1 [Gorton, Ian; Wynne, Adam; Almquist, Justin; Chatterton, Jack] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gorton, I (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Gorton, Ian/A-8247-2009 NR 18 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3092-5 PY 2008 BP 95 EP 104 DI 10.1109/WICSA.2008.21 PG 10 WC Computer Science, Software Engineering SC Computer Science GA BHL74 UT WOS:000254145600011 ER PT J AU Shabalovskaya, S Van Humbeeck, J AF Shabalovskaya, S. Van Humbeeck, J. BE Yoneyama, T Miyazaki, S TI Biocompatibility of Nitinol for biomedical applications SO SHAPE MEMORY ALLOYS FOR BIOMEDICAL APPLICATIONS SE Woodhead Publishing in Materials LA English DT Article; Book Chapter DE Nitinol; Ti-Ni alloys; biocompatibility; nickel release; superelastic stents; bone implant; Ni-Ti ID SHAPE-MEMORY ALLOYS; IMMERSION ION-IMPLANTATION; ABDOMINAL AORTIC-ANEURYSM; IN-VIVO BIOCOMPATIBILITY; EXPANDING CORONARY STENT; POROUS TITANIUM-NICKEL; STAINLESS-STEEL STENTS; CORROSION BEHAVIOR; FOLLOW-UP; MECHANICAL-PROPERTIES AB Recent studies on the biocompatibility of dense and porous Nitinol (Ti-Ni) in vitro and in vivo are reviewed and the biological status of this biomaterial is evaluated. The evolution of our knowledge and understanding of the biological aspects is emphasized and both Nitinol's strong attributes and its deficits are pointed out. Nickel release and cell responses are analysed, and the mechanisms of Ni accumulation in the surface sublayers along with its low-temperature diffusion to the interfaces are addressed. Plasma protein adsorption and platelet adhesion pertinent to Nitinol thrombogenicity are analysed and the comparative biocompatibility of modified Nitinol surfaces is discussed. An analysis of performances of self-expanding implant devices is presented and the problem with Nitinol debris is addressed. This chapter will be of interest for both academic and industrial use. C1 [Shabalovskaya, S.] Ames Lab, Ames, IA 50011 USA. [Van Humbeeck, J.] Katholieke Univ Leuven, MTM, B-3001 Louvain, Belgium. RP Shabalovskaya, S (reprint author), Ames Lab, Ames, IA 50011 USA. EM svetinol@yahoo.com; Jan.Vanhumbeeck@mtm.kuleuven.be NR 126 TC 6 Z9 6 U1 0 U2 3 PU WOODHEAD PUBL LTD PI CAMBRIDGE PA ABINGTON HALL ABINGTON, CAMBRIDGE CB1 6AH, CAMBS, ENGLAND BN 978 1 84569 344 2 J9 WOODHEAD PUBL MATER PY 2008 BP 194 EP 233 PG 40 WC Metallurgy & Metallurgical Engineering; Materials Science, Biomaterials SC Metallurgy & Metallurgical Engineering; Materials Science GA BOF09 UT WOS:000276419400010 ER PT J AU Bessette, GC AF Bessette, Greg C. TI Modeling blast loading on buried reinforced concrete structures with Zapotec SO SHOCK AND VIBRATION LA English DT Article AB A coupled Euler-Lagrange solution approach is used to model the response of a buried reinforced concrete structure subjected to a close-in detonation of a high explosive charge. The coupling algorithm is discussed along with a set of benchmark calculations involving detonations in clay and sand. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bessette, GC (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM gcbesse@sandia.gov NR 8 TC 1 Z9 1 U1 1 U2 2 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1070-9622 J9 SHOCK VIB JI Shock Vib. PY 2008 VL 15 IS 2 BP 137 EP 146 PG 10 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 274HM UT WOS:000253992400003 ER PT J AU Glimm, J Ji, XM Li, JQ Li, XL Zhang, P Zhang, T Zheng, YX AF Glimm, James Ji, Xiaomei Li, Jiequan Li, Xiaolin Zhang, Peng Zhang, Tong Zheng, Yuxi TI TRANSONIC SHOCK FORMATION IN A RAREFACTION RIEMANN PROBLEM FOR THE 2D COMPRESSIBLE EULER EQUATIONS SO SIAM JOURNAL ON APPLIED MATHEMATICS LA English DT Article DE 2D Riemann problem; gas dynamics; shock waves; generalized characteristic analysis; front tracking method ID 2-DIMENSIONAL GAS-DYNAMICS; PHYSICS AB It is perhaps surprising for a shock wave to exist in the solution of a rarefaction Riemann problem for the compressible Euler equations in two space dimensions. We present numerical evidence and generalized characteristic analysis to establish the existence of a shock wave in such a 2D Riemann problem, defined by the interaction of four rarefaction waves. We consider both the customary con. guration of waves at the right angle and also an oblique con. guration for the rarefaction waves. Two distinct mechanisms for the formation of a shock wave are discovered as the angle between the waves is varied. C1 [Glimm, James; Ji, Xiaomei; Li, Xiaolin] SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. [Glimm, James] Brookhaven Natl Lab, Computat Sci Ctr, Upton, NY 11973 USA. [Li, Jiequan; Zhang, Peng] Capital Normal Univ, Dept Math, Beijing 100037, Peoples R China. [Zheng, Yuxi] Penn State Univ, Dept Math, University Pk, PA 16802 USA. [Zhang, Tong] Chinese Acad Math & Syst Sci, Inst Math, Beijing 100080, Peoples R China. RP Ji, XM (reprint author), SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. EM glimm@ams.sunysb.edu; xji@ams.sunysb.edu; jiequan@mail.cnu.edu.cn; linli@ams.sunysb.edu; pzhang@mail.cnu.edu.cn; tzhang@math.ac.cn; yzheng@math.psu.edu NR 21 TC 27 Z9 28 U1 0 U2 4 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1399 J9 SIAM J APPL MATH JI SIAM J. Appl. Math. PY 2008 VL 69 IS 3 BP 720 EP 742 DI 10.1137/07070632X PG 23 WC Mathematics, Applied SC Mathematics GA 403SU UT WOS:000263103100005 ER PT J AU Sviercoski, RF Winter, CL Warrick, AW AF Sviercoski, R. F. Winter, C. L. Warrick, A. W. TI Analytical approximation for the generalized Laplace equation with step function coefficient SO SIAM JOURNAL ON APPLIED MATHEMATICS LA English DT Article DE Laplace's equation; L(p)-approximation; homogenization; cell-problem; generalized Voigt-Reiss inequality ID HOMOGENIZATION; PERMEABILITY; FLOW AB Many problems in science and engineering require the solution of the steady-state diffusion equation with a highly oscillatory coefficient. In this paper, we propose an analytical approximation (u) over tilde (x) is an element of L(p)(Omega), 1 <= p <= infinity, for the generalized Laplace equation. del . (K (x) del u(x)) = 0 in Omega subset of R(n), with prescribed boundary conditions and the coefficient function K(x) is an element of L(p)(Omega) defined as a step function, not necessarily periodic. The proposed solution can be regarded as an approximation to the weak solution belonging to W(1,p)(Omega), the Sobolev space. When the coefficient function describes inclusions in a main matrix, then K( x) is a periodic function, and such formulation leads to an approximation, in L(p)(Omega), to the solution of the periodic cell-problem, del . (K(epsilon(-1)x)del w(epsilon(-1)x)) = del . ( K(epsilon(-1)x) 1). The solution to the cell-problem is the key information needed to obtain the upscaled coefficient and therefore the zeroth-order approximation for a generalized elliptic equation with highly oscillating coefficient in Omega subset of R(n). Our numerical computation of the error between the proposed analytical approximation for the cell- problem, (omega) over tilde(epsilon(-1)x) in L(p)(Omega), and the solution omega(epsilon(-1)x) in W(1,2)(Omega), demonstrates to converge in the L(2)-norm, when the scale parameter e approaches zero. The proposed approximation leads to the lower bound of the generalized Voigt-Reiss inequality, which is a more accurate two-sided estimate than the classical Voigt-Reiss inequality. As an application, we compute our approximate value for the homogenized coefficient when the heterogeneous coefficients are inclusions such as squares, circles, and lozenges, and we demonstrate that the results underestimate the effective coefficient with an error of 10% on average, when compared with published numerical results. C1 [Sviercoski, R. F.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Winter, C. L.] NCAR, Boulder, CO 80305 USA. [Warrick, A. W.] Univ Arizona, Program Appl Math, Tucson, AZ 85721 USA. Univ Arizona, SWES, Tucson, AZ 85721 USA. RP Sviercoski, RF (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. EM rsvier@lanl.gov; lwinter@ucar.edu; aww@ag.arizona.edu RI Winter, C. Larrabee/D-3918-2013 NR 18 TC 5 Z9 5 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1399 J9 SIAM J APPL MATH JI SIAM J. Appl. Math. PY 2008 VL 68 IS 5 BP 1268 EP 1281 DI 10.1137/070683465 PG 14 WC Mathematics, Applied SC Mathematics GA 309HY UT WOS:000256452500004 ER PT J AU Hrynkiv, V Lenhart, S Protopopescu, V AF Hrynkiv, Volodymyr Lenhart, Suzanne Protopopescu, Vladimir TI Optimal control of a convective boundary condition in a thermistor problem SO SIAM JOURNAL ON CONTROL AND OPTIMIZATION LA English DT Article DE optimal control; thermistor problem; elliptic systems ID EXISTENCE; TEMPERATURE AB We consider the optimal control of a two-dimensional steady-state thermistor. The problem is described by a system of two nonlinear elliptic partial differential equations with appropriate boundary conditions which model the coupling of the thermistor to its surroundings. Based on physical considerations, an objective functional to be minimized is introduced and the convective boundary coefficient is taken as the control. Existence and uniqueness of the optimal control are proven. To characterize this optimal control, the optimality system consisting of the state and adjoint equations is derived. C1 [Hrynkiv, Volodymyr] Worcester Polytech Inst, Dept Math Sci, Worcester, MA 01609 USA. [Lenhart, Suzanne] Univ Tennessee, Dept Math, Knoxville, TN 37996 USA. [Protopopescu, Vladimir] Oak Ridge Natl Lab, Comp Sci & Engn Div, Oak Ridge, TN 37831 USA. RP Hrynkiv, V (reprint author), Worcester Polytech Inst, Dept Math Sci, Worcester, MA 01609 USA. EM vhrynkiv@wpi.edu; lenhart@math.utk.edu; protopopesva@ornl.gov NR 21 TC 3 Z9 3 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0363-0129 J9 SIAM J CONTROL OPTIM JI SIAM J. Control Optim. PY 2008 VL 47 IS 1 BP 20 EP 39 DI 10.1137/06066401X PG 20 WC Automation & Control Systems; Mathematics, Applied SC Automation & Control Systems; Mathematics GA 260NC UT WOS:000253016000002 ER PT J AU Hauck, CD Levermore, CD Tits, AL AF Hauck, Cory D. Levermore, C. David Tits, Andre L. TI Convex duality and entropy-based moment closures: Characterizing degenerate densities SO SIAM JOURNAL ON CONTROL AND OPTIMIZATION LA English DT Article DE convex duality; convex optimization; optimization in function spaces; kinetic theory; entropy-based closures; moment equations; gas dynamics ID MINIMIZATION PROBLEMS; HIERARCHIES; EQUATION AB A common method for constructing a function from a finite set of moments is to solve a constrained minimization problem. The idea is to find, among all functions with the given moments, that function which minimizes a physically motivated, strictly convex functional. In the kinetic theory of gases, this functional is the kinetic entropy; the given moments are macroscopic densities; and the solution to the constrained minimization problem is used to formally derive a closed system of partial differential equations which describe how the macroscopic densities evolve in time. Moment equations are useful because they simplify the kinetic, phase-space description of a gas, and with entropy-based closures, they retain many of the fundamental properties of kinetic transport. Unfortunately, in many situations, macroscopic densities can take on values for which the constrained minimization problem does not have a solution. Essentially, this is because the moments are not continuous functionals with respect to the L(1) topology. In this paper, we give a geometric description of these so-called degenerate densities in the most general possible setting. Our key tool is the complementary slackness condition that is derived from a dual formulation of a minimization problem with relaxed constraints. We show that the set of degenerate densities is a union of convex cones and, under reasonable assumptions, that this set is small in both a topological and a measure-theoretic sense. This result is important for further assessment and implementation of entropy- based moment closures. C1 [Hauck, Cory D.] Los Alamos Natl Lab, Computat Phys & Methods CCS 2, Los Alamos, NM 87545 USA. [Hauck, Cory D.] Los Alamos Natl Lab, Ctr Nonlinear Studies CNLS, Los Alamos, NM 87545 USA. [Levermore, C. David] Univ Maryland, Dept Math, College Pk, MD 20742 USA. [Levermore, C. David] Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. [Tits, Andre L.] Univ Maryland, Dept Elect & Comp Engn, College Pk, MD 20742 USA. [Tits, Andre L.] Univ Maryland, Syst Res Inst, College Pk, MD 20742 USA. RP Hauck, CD (reprint author), Los Alamos Natl Lab, Computat Phys & Methods CCS 2, POB 1663, Los Alamos, NM 87545 USA. EM cdhauck@lanl.gov; lvrmr@math.umd.edu; andre@umd.edu RI Tits, Andre/B-3355-2012 OI Tits, Andre/0000-0002-1542-7889 FU Department of Mathematics at the University of Maryland, College Park; National Science Foundation [DMS-0240049, DMI-0422931]; U. S. Department of Energy [DE-AC52-06NA25396, DEFG0204ER25655]; DOE Office of Science Advanced Computing Research (ASCR) Program FX The work of this author was supported in part by the National Science Foundation under Grant DMI-0422931 and by the U. S. Department of Energy under Grant DEFG0204ER25655. NR 34 TC 20 Z9 20 U1 0 U2 5 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0363-0129 J9 SIAM J CONTROL OPTIM JI SIAM J. Control Optim. PY 2008 VL 47 IS 4 BP 1977 EP 2015 DI 10.1137/070691139 PG 39 WC Automation & Control Systems; Mathematics, Applied SC Automation & Control Systems; Mathematics GA 343ZP UT WOS:000258895300015 ER PT J AU Abramson, MA Asaki, TJ Dennis, JE O'Reilly, KR Pingel, RL AF Abramson, Mark A. Asaki, Thomas J. Dennis, J. E., Jr. O'Reilly, Kevin R. Pingel, Rachael L. TI Quantitative Object Reconstruction Using Abel Transform X-Ray Tomography and Mixed Variable Optimization SO SIAM JOURNAL ON IMAGING SCIENCES LA English DT Article DE mixed variable optimization; derivative-free optimization; mesh adaptive direct search (MADS) algorithms; x-ray tomography; Abel transforms ID PATTERN SEARCH ALGORITHMS; TOTAL-VARIATION REGULARIZATION; CONSTRAINED MINIMIZATION; INTEGRAL-EQUATION; INVERSION AB This paper introduces a new approach to the problem of quantitative reconstruction of an object from few radiographic views. A mixed variable programming problem is formulated in which the variables of interest are the number and types of materials and geometric parameters. To demonstrate the technique, we considered the problem of reconstructing cylindrically symmetric objects of multiple layers from a single radiograph. The mixed variable pattern search algorithm for linearly constrained problems was applied by means of the NOMADm MATLAB software package. Numerical results are presented for several test configurations and show that, while there are difficulties yet to be overcome, the method is promising for solving this class of problems. C1 [Abramson, Mark A.] Boeing Co, Seattle, WA 98124 USA. [Asaki, Thomas J.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Dennis, J. E., Jr.] Rice Univ, Dept Computat & Appl Math, Houston, TX 77005 USA. [Pingel, Rachael L.] Brigham Young Univ, Dept Math, Provo, UT 84602 USA. RP Abramson, MA (reprint author), Boeing Co, POB 3707,Mail Code 7L-21, Seattle, WA 98124 USA. EM Mark.A.Abramson@boeing.com; tjasaki@gmail.com; dennis@rice.edu; kevin.oreilly@edwards.af.mil; rachaelp@byu.net RI Dennis, John/A-6910-2008 FU LANL; AFOSR; Boeing Company; ExxonMobil Upstream Research Company FX The Boeing Company, P.O. Box 3707, Mail Code 7L-21, Seattle, WA 98124-2207 (Mark.A.Abramson@boeing.com). This author's work was supported by LANL.; Department of Computational and Applied Mathematics, Rice University, Houston, TX 77005 (dennis@rice.edu, http://www.caam.rice.edu/~dennis). Current address: 8419 42nd Ave. SW, Seattle, WA 98136-2360. This author's work was supported by LANL, AFOSR, The Boeing Company, and ExxonMobil Upstream Research Company. NR 32 TC 6 Z9 6 U1 1 U2 11 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1936-4954 J9 SIAM J IMAGING SCI JI SIAM J. Imaging Sci. PY 2008 VL 1 IS 3 BP 322 EP 342 DI 10.1137/08071380X PG 21 WC Computer Science, Artificial Intelligence; Computer Science, Software Engineering; Mathematics, Applied; Imaging Science & Photographic Technology SC Computer Science; Mathematics; Imaging Science & Photographic Technology GA V11YS UT WOS:000207567500006 ER PT J AU Yang, C Gao, WG Meza, JC AF Yang, Chao Gao, Weiguo Meza, Juan C. TI ON THE CONVERGENCE OF THE SELF-CONSISTENT FIELD ITERATION FOR A CLASS OF NONLINEAR EIGENVALUE PROBLEMS SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE nonlinear eigenvalue problem; self-consistent field iteration polynomial ID EQUATIONS AB We investigate the convergence of the self-consistent field (SCF) iteration used to solve a class of nonlinear eigenvalue problems. We show that for the class of problems considered, the SCF iteration produces a sequence of approximate solutions that contain two convergent subsequences. These subsequences may converge to two different limit points, neither of which is the solution to the nonlinear eigenvalue problem. We identify the condition under which the SCF iteration becomes a contractive fixed point iteration that guarantees its convergence. This condition is characterized by an upper bound placed on a parameter that weighs the contribution from the nonlinear component of the eigenvalue problem. We derive such a bound for the general case as well as for a special case in which the dimension of the problem is 2. C1 [Yang, Chao; Meza, Juan C.] Lawrence Berkeley Natl Lab, Comput Res Div, Berkeley, CA 94720 USA. [Gao, Weiguo] Fudan Univ, Sch Math Sci, Shanghai, Peoples R China. RP Yang, C (reprint author), Lawrence Berkeley Natl Lab, Comput Res Div, Berkeley, CA 94720 USA. EM CYang@lbl.gov; wggao@fudan.edu.cn; JCMeza@lbl.gov OI Meza, Juan/0000-0003-4543-0349 FU U.S. Department of Energy [DE-AC03-76SF00098] FX The work of these authors was supported by the Director, Office of Science, Division of Mathematical, Information, and Computational Sciences of the U.S. Department of Energy under contract DE-AC03-76SF00098. NR 11 TC 4 Z9 4 U1 1 U2 4 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0895-4798 J9 SIAM J MATRIX ANAL A JI SIAM J. Matrix Anal. Appl. PY 2008 VL 30 IS 4 BP 1773 EP 1788 DI 10.1137/080716293 PG 16 WC Mathematics, Applied SC Mathematics GA 403TA UT WOS:000263103700027 ER PT J AU Bochev, PB Ridzal, D AF Bochev, Pavel B. Ridzal, Denis TI REHABILITATION OF THE LOWEST-ORDER RAVIART-THOMAS ELEMENT ON QUADRILATERAL GRIDS SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE Raviart-Thomas; quadrilateral; mixed methods; least-squares methods; mimetic methods ID LOGICALLY RECTANGULAR GRIDS; NATURAL DISCRETIZATIONS; FINITE-ELEMENTS; DIVERGENCE; GRADIENT; CURL AB A recent study [D. N. Arnold, D. Boffi, and R. S. Falk, SIAM J. Numer. Anal., 42 (2005), pp. 2429-2451] reveals that convergence of finite element methods using H(div, Omega)-compatible finite element spaces deteriorates on nona. ne quadrilateral grids. This phenomena is particularly troublesome for the lowest-order Raviart-Thomas elements, because it implies loss of convergence in some norms for finite element solutions of mixed and least-squares methods. In this paper we propose reformulation of finite element methods, based on the natural mimetic divergence operator [M. Shashkov, Conservative Finite Difference Methods on General Grids, CRC Press, Boca Raton, FL, 1996], which restores the order of convergence. Reformulations of mixed Galerkin and least-squares methods for the Darcy equation illustrate our approach. We prove that reformulated methods converge optimally with respect to a norm involving the mimetic divergence operator. Furthermore, we prove that standard and reformulated versions of the mixed Galerkin method lead to identical linear systems, but the two versions of the least-squares method are veritably different. The surprising conclusion is that the degradation of convergence in the mixed method on nona. ne quadrilateral grids is superficial, and that the lowest-order Raviart-Thomas elements are safe to use in this method. However, the breakdown in the least-squares method is real, and there one should use our proposed reformulation. C1 [Bochev, Pavel B.; Ridzal, Denis] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bochev, PB (reprint author), Sandia Natl Labs, POB 5800,MS 1320, Albuquerque, NM 87185 USA. EM pbboche@sandia.gov; dridzal@sandia.gov NR 22 TC 9 Z9 9 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 47 IS 1 BP 487 EP 507 DI 10.1137/070704265 PG 21 WC Mathematics, Applied SC Mathematics GA 403TB UT WOS:000263103800023 ER PT J AU Hetmaniuk, U Knupp, P AF Hetmaniuk, U. Knupp, P. TI LOCAL ANISOTROPIC INTERPOLATION ERROR ESTIMATES BASED ON DIRECTIONAL DERIVATIVES ALONG EDGES SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE affine equivalent elements; anisotropic estimates; finite element interpolation error; Lagrange interpolation ID FINITE-ELEMENT METHOD; LINEAR INTERPOLATION; TRIANGLE AB We present new local anisotropic error estimates for the Lagrangian finite element interpolation. The bounds apply to a. ne equivalent elements and use information from directional derivatives of the function to interpolate along a set of adjacent edges. These new bounds do not require any geometric limitation but may vary, in some cases, with the node ordering. Several existing results are recovered from the new bounds. Examples compare the asymptotic behavior of the new and existing bounds when the diameter of the element goes to zero. For some elements with small or large angles, our new bound exhibits the same asymptotic behavior as the norm of the interpolation error while existing results do not have the correct asymptotic behavior. C1 [Hetmaniuk, U.; Knupp, P.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hetmaniuk, U (reprint author), Sandia Natl Labs, POB 5800,MS 1320, Albuquerque, NM 87185 USA. EM ulhetma@sandia.gov; pknupp@sandia.gov FU United States Department of Energy [DE-AC04-94AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94AL85000. NR 18 TC 2 Z9 2 U1 1 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 47 IS 1 BP 575 EP 595 DI 10.1137/060666524 PG 21 WC Mathematics, Applied SC Mathematics GA 403TB UT WOS:000263103800027 ER PT J AU Bauer, AL Loubere, R Wendroff, B AF Bauer, Amy L. Loubere, Raphaeerl Wendroff, Burton TI On stability of staggered schemes SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE staggered schemes; stability; wave equations; Euler equations ID EQUATIONS; ACCURACY AB This paper investigates the theoretical stability bound of a Lagrangian staggered scheme used to solve hydrodynamics equations. We present the two-dimensional (2D) wave equation as a possible model for this study and, by using the numerical radius of the amplification matrix, we prove that the family of schemes defined with two time-centering parameters is limited by a non-classical stability bound limit defined with an analytical curve. We further show that 2D numerical experiments agree with this theoretical result. C1 [Bauer, Amy L.; Wendroff, Burton] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. [Loubere, Raphaeerl] Univ Toulouse 3, Inst Math, F-31062 Toulouse, France. [Loubere, Raphaeerl] Univ Toulouse 3, CNRS, UMR 5219, F-31062 Toulouse, France. RP Bauer, AL (reprint author), Los Alamos Natl Lab, Div Theoret, T-14,MS-B262, Los Alamos, NM 87545 USA. EM albauer@lanl.gov; loubere@mip.ups-tlse.fr; bbw@lanl.gov NR 8 TC 2 Z9 3 U1 0 U2 4 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 2 BP 996 EP 1011 DI 10.1137/060660151 PG 16 WC Mathematics, Applied SC Mathematics GA 271UV UT WOS:000253815100018 ER PT J AU Estep, D Ginting, V Ropp, D Shadid, JN Tavener, S AF Estep, D. Ginting, V. Ropp, D. Shadid, J. N. Tavener, S. TI An a posteriori - A priori analysis of multiscale operator splitting SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE a posteriori error analysis; adjoint problem; discontinuous Galerkin method; generalized Green's function; goal oriented error estimates; multiscale method; operator decomposition; operator splitting; reaction-diffusion equations; residual ID ORDINARY DIFFERENTIAL-EQUATIONS; TIME-INTEGRATION METHODS; DIFFUSION EQUATIONS; ONE-STEP; APPROXIMATIONS; CONVERGENCE; STABILITY; ACCURACY; SCHEMES; SYSTEMS AB In this paper, we analyze a multiscale operator splitting method for solving systems of ordinary differential equations such as those that result upon space discretization of a reaction diffusion equation. Our goal is to analyze and accurately estimate the error of the numerical solution, including the effects of any instabilities that can result from multiscale operator splitting. We present both an a priori error analysis and a new type of hybrid a priori-a posteriori error analysis for an operator splitting discontinuous Galerkin finite element method. Both analyses clearly distinguish between the effects of the operator splitting and the discretization of each component of the decomposed problem. The hybrid analysis has the form of a computable a posteriori leading order expression and a provably higher order a priori expression. The hybrid analysis takes into account the fact that the adjoint problems for the original problem and a multiscale operator splitting discretization differ insignificant ways. In particular, this provides the means to monitor global instabilities that can arise from operator splitting. C1 [Estep, D.; Ginting, V.; Tavener, S.] Colorado State Univ, Dept Math, Ft Collins, CO 80523 USA. [Estep, D.] Colorado State Univ, Dept Stat, Ft Collins, CO 80523 USA. [Ropp, D.] SAIC, Arlington, VA 22203 USA. [Shadid, J. N.] Sandia Natl Labs, Computat Sci R&D Grp, Albuquerque, NM 87185 USA. RP Estep, D (reprint author), Colorado State Univ, Dept Math, Ft Collins, CO 80523 USA. EM estep@math.colostate.edu; ginting@math.colostate.edu; DAVID.L.ROPP@saic.com; jnshadi@sandia.gov; tavener@math.colostate.edu NR 34 TC 25 Z9 25 U1 2 U2 6 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 EI 1095-7170 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 3 BP 1116 EP 1146 DI 10.1137/07068237X PG 31 WC Mathematics, Applied SC Mathematics GA 295UW UT WOS:000255500400002 ER PT J AU Brown, PN Walker, HF Wasyk, R Woodward, CS AF Brown, Peter N. Walker, Homer F. Wasyk, Rebecca Woodward, Carol S. TI On using approximate finite differences in matrix-free Newton-Krylov methods SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE matrix-free Newton-Krylov methods; Newton-GMRES methods; Newton-Arnoldi methods; Newton's method; Krylov subspace methods; GMRES method; Arnoldi method ID LINEAR-SYSTEMS; EQUATIONS; SOLVERS AB A Newton-Krylov method is an implementation of Newton's method in which a Krylov subspace method is used to solve approximately the linear systems that characterize steps of Newton's method. Newton-Krylov methods are often implemented in "matrix-free" form, in which the Jacobian-vector products required by the Krylov solver are approximated by finite differences. Here we consider using approximate function values in these finite differences. We first formulate a finite-difference Arnoldi process that uses approximate function values. We then outline a Newton Krylov method that uses an implementation of the GMRES or Arnoldi method based on this process, and we develop a local convergence analysis for it, giving sufficient conditions on the approximate function values for desirable local convergence properties to hold. We conclude with numerical experiments involving particular function-value approximations suitable for nonlinear diffusion problems. For this case, conditions are given for meeting the convergence assumptions for both lagging and linearizing the nonlinearity in the function evaluation. C1 [Brown, Peter N.; Woodward, Carol S.] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. [Walker, Homer F.; Wasyk, Rebecca] Worcester Polytech Inst, Dept Math Sci, Worcester, MA 01609 USA. RP Brown, PN (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Box 808,L-561, Livermore, CA 94551 USA. EM pnbrown@llnl.gov; walker@wpi.edu; wasykrd@wpi.edu; cswoodward@llnl.gov RI Woodward, Carol/M-4008-2014 NR 19 TC 7 Z9 7 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 4 BP 1892 EP 1911 DI 10.1137/060652749 PG 20 WC Mathematics, Applied SC Mathematics GA 309IH UT WOS:000256453400011 ER PT J AU Pawlowski, RP Simonis, JP Walker, HF Shadid, JN AF Pawlowski, Roger P. Simonis, Joseph P. Walker, Homer F. Shadid, John N. TI Inexact Newton dogleg methods SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE dogleg methods; trust-region methods; inexact Newton methods; Newton's method; Newton iterative methods; Newton-Krylov methods; Newton-GMRES methods; truncated-Newton methods; globalized Newton methods; fully-coupled solution methods; Navier-Stokes equations ID NAVIER-STOKES EQUATIONS; FULLY COUPLED SOLUTION; KRYLOV METHODS; CONVERGENCE THEORY; NONLINEAR-SYSTEMS; LINEAR-SYSTEMS; ALGORITHMS; FLOW; OPTIMIZATION; GMRES AB The dogleg method is a classical trust-region technique for globalizing Newton's method. While it is widely used in optimization, including large-scale optimization via truncated-Newton approaches, its implementation in general inexact Newton methods for systems of nonlinear equations can be problematic. In this paper, we first outline a very general dogleg method suitable for the general inexact Newton context and provide a global convergence analysis for it. We then discuss certain issues that may arise with the standard dogleg implementational strategy and propose modified strategies that address them. Newton-Krylov methods have provided important motivation for this work, and we conclude with a report on numerical experiments involving a Newton-GMRES dogleg method applied to benchmark CFD problems. C1 [Pawlowski, Roger P.; Shadid, John N.] Sandia Natl Labs, Dept Computat Sci, Albuquerque, NM 87185 USA. [Simonis, Joseph P.; Walker, Homer F.] Worcester Polytech Inst, Dept Math Sci, Worcester, MA 01609 USA. RP Pawlowski, RP (reprint author), Sandia Natl Labs, Dept Computat Sci, MS 0316,POB 5800, Albuquerque, NM 87185 USA. EM rppawlo@sandia.gov; jpsimoni@wpi.edu; walker@wpi.edu; jnshadi@sandia.gov NR 49 TC 11 Z9 11 U1 0 U2 5 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 4 BP 2112 EP 2132 DI 10.1137/050632166 PG 21 WC Mathematics, Applied SC Mathematics GA 309IH UT WOS:000256453400021 ER PT J AU Dohrmann, CR Klawonn, A Widlund, OB AF Dohrmann, Clark R. Klawonn, Axel Widlund, Olof B. TI Domain decomposition for less regular subdomains: Overlapping Schwarz in two dimensions SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE domain decomposition; overlapping Schwarz; preconditioners; iterative methods; irregular subdomains; John domains ID ELLIPTIC PROBLEMS; DISCONTINUOUS COEFFICIENTS AB In the theory of domain decomposition methods, it is often assumed that each subdomain is the union of a small set of coarse triangles or tetrahedra. In this study, extensions to the existing theory which accommodate subdomains with much less regular shapes are presented; the subdomains are required only to be John domains. Attention is focused on overlapping Schwarz preconditioners for problems in two dimensions with a coarse space component of the preconditioner, which allows for good results even for coefficients which vary considerably. It is shown that the condition number of the domain decomposition method is bounded by C( 1 + H/delta)( 1 + log( H/h))(2), where the constant C is independent of the number of subdomains and possible jumps in coefficients between subdomains. Numerical examples are provided which confirm the theory and demonstrate very good performance of the method for a variety of subregions including those obtained when a mesh partitioner is used for the domain decomposition. C1 [Dohrmann, Clark R.] Sandia Natl Labs, Struct Dynam Res Dept, Albuquerque, NM 87185 USA. [Klawonn, Axel] Univ Duisburg Essen, Fachbereich Math, D-45117 Essen, Germany. [Widlund, Olof B.] NYU, Courant Inst, Dept Math, New York, NY 10012 USA. RP Dohrmann, CR (reprint author), Sandia Natl Labs, Struct Dynam Res Dept, POB 5800, Albuquerque, NM 87185 USA. EM crdohrm@sandia.gov; axel.klawonn@uni-due.de; widlund@cims.nyu.edu RI Klawonn, Axel/P-8705-2014 NR 28 TC 30 Z9 30 U1 0 U2 4 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 4 BP 2153 EP 2168 DI 10.1137/070685841 PG 16 WC Mathematics, Applied SC Mathematics GA 309IH UT WOS:000256453400023 ER PT J AU Nobile, F Tempone, R Webster, CG AF Nobile, F. Tempone, R. Webster, C. G. TI A sparse grid stochastic collocation method for partial differential equations with random input data SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE collocation techniques; stochastic PDEs; finite elements; uncertainty quantification; sparse grids; Smolyak approximation; multivariate polynomial approximation ID POLYNOMIAL CHAOS; UNCERTAINTY; QUADRATURE; INTERPOLATION; COEFFICIENTS AB This work proposes and analyzes a Smolyak-type sparse grid stochastic collocation method for the approximation of statistical quantities related to the solution of partial differential equations with random coeffcients and forcing terms ( input data of the model). To compute solution statistics, the sparse grid stochastic collocation method uses approximate solutions, produced here by finite elements, corresponding to a deterministic set of points in the random input space. This naturally requires solving uncoupled deterministic problems as in the Monte Carlo method. If the number of random variables needed to describe the input data is moderately large, full tensor product spaces are computationally expensive to use due to the curse of dimensionality. In this case the sparse grid approach is still expected to be competitive with the classical Monte Carlo method. Therefore, it is of major practical relevance to understand in which situations the sparse grid stochastic collocation method is more efficient than Monte Carlo. This work provides error estimates for the fully discrete solution using L(q) norms and analyzes the computational efficiency of the proposed method. In particular, it demonstrates algebraic convergence with respect to the total number of collocation points and quantifies the effect of the dimension of the problem ( number of input random variables) in the final estimates. The derived estimates are then used to compare the method with Monte Carlo, indicating for which problems the former is more efficient than the latter. Computational evidence complements the present theory and shows the effectiveness of the sparse grid stochastic collocation method compared to full tensor and Monte Carlo approaches. C1 [Nobile, F.] Politecn Milan, Dipartimento Matemat F Brioschi, MOX, I-20133 Milan, Italy. [Tempone, R.] Florida State Univ, Dept Math, Tallahassee, FL 32306 USA. [Tempone, R.] Florida State Univ, Sch Computat Sci, Tallahassee, FL 32306 USA. [Tempone, R.] Royal Inst Technol, Sch Comp Sci & Commun, S-10044 Stockholm, Sweden. [Webster, C. G.] Sandia Natl Labs, Optimizat & Uncertainty Quantificat Dept, Albuquerque, NM 87185 USA. RP Nobile, F (reprint author), Politecn Milan, Dipartimento Matemat F Brioschi, MOX, I-20133 Milan, Italy. EM fabio.nobile@polimi.it; rtempone@scs.fsu.edu; cgwebst@sandia.gov RI nobile, fabio/B-6515-2014; TEMPONE, RAUL/G-6557-2014; OI nobile, fabio/0000-0002-8130-0114; TEMPONE, RAUL/0000-0003-1967-4446; Webster, Clayton/0000-0002-1375-0359 NR 37 TC 292 Z9 296 U1 4 U2 34 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 5 BP 2309 EP 2345 DI 10.1137/060663660 PG 37 WC Mathematics, Applied SC Mathematics GA 327RQ UT WOS:000257746600005 ER PT J AU Nobile, F Tempone, R Webster, CG AF Nobile, F. Tempone, R. Webster, C. G. TI An anisotropic sparse grid stochastic collocation method for partial differential equations with random input data SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE collocation techniques; PDEs with random data; differential equations; finite elements; uncertainty quantification; anisotropic sparse grids; Smolyak sparse approximation; multivariate polynomial approximation ID ELLIPTIC PROBLEMS; FINITE-ELEMENTS; UNCERTAINTY; COEFFICIENTS; APPROXIMATIONS; PROPAGATION; EXPANSIONS; QUADRATURE; CHAOS AB This work proposes and analyzes an anisotropic sparse grid stochastic collocation method for solving partial differential equations with random coefficients and forcing terms ( input data of the model). The method consists of a Galerkin approximation in the space variables and a collocation, in probability space, on sparse tensor product grids utilizing either Clenshaw-Curtis or Gaussian knots. Even in the presence of nonlinearities, the collocation approach leads to the solution of uncoupled deterministic problems, just as in the Monte Carlo method. This work includes a priori and a posteriori procedures to adapt the anisotropy of the sparse grids to each given problem. These procedures seem to be very effective for the problems under study. The proposed method combines the advantages of isotropic sparse collocation with those of anisotropic full tensor product collocation: the first approach is effective for problems depending on random variables which weigh approximately equally in the solution, while the benefits of the latter approach become apparent when solving highly anisotropic problems depending on a relatively small number of random variables, as in the case where input random variables are Karhunen-Loeve truncations of "smooth" random fields. This work also provides a rigorous convergence analysis of the fully discrete problem and demonstrates ( sub) exponential convergence in the asymptotic regime and algebraic convergence in the preasymptotic regime, with respect to the total number of collocation points. It also shows that the anisotropic approximation breaks the curse of dimensionality for a wide set of problems. Numerical examples illustrate the theoretical results and are used to compare this approach with several others, including the standard Monte Carlo. In particular, for moderately large-dimensional problems, the sparse grid approach with a properly chosen anisotropy seems to be very efficient and superior to all examined methods. C1 [Nobile, F.] Politecn Milan, Dipartimento Matemat F Brioschi, MOX, I-20133 Milan, Italy. [Tempone, R.] Florida State Univ, Dept Math, Tallahassee, FL 32306 USA. [Tempone, R.] Florida State Univ, Sch Computat Sci, Tallahassee, FL 32306 USA. [Tempone, R.] Royal Inst Technol, Sch Comp Sci & Commun, S-10044 Stockholm, Sweden. [Webster, C. G.] Sandia Natl Labs, Optimizat & Uncertainty Quantificat, Albuquerque, NM 87185 USA. RP Nobile, F (reprint author), Politecn Milan, Dipartimento Matemat F Brioschi, MOX, I-20133 Milan, Italy. EM fabio.nobile@polimi.it; rtempone@scs.fsu.edu; cgwebst@sandia.gov RI nobile, fabio/B-6515-2014; TEMPONE, RAUL/G-6557-2014; OI nobile, fabio/0000-0002-8130-0114; TEMPONE, RAUL/0000-0003-1967-4446; Webster, Clayton/0000-0002-1375-0359 NR 30 TC 179 Z9 184 U1 2 U2 16 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 5 BP 2411 EP 2442 DI 10.1137/070680540 PG 32 WC Mathematics, Applied SC Mathematics GA 327RQ UT WOS:000257746600009 ER PT J AU Boman, EG Hendrickson, B Vavasis, S AF Boman, Erik G. Hendrickson, Bruce Vavasis, Stephen TI SOLVING ELLIPTIC FINITE ELEMENT SYSTEMS IN NEAR-LINEAR TIME WITH SUPPORT PRECONDITIONERS SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE finite elements; preconditioning; matrix algorithm; support graph; diagonal dominance ID GRAPH PRECONDITIONERS; MATRICES AB We consider linear systems arising from the use of the finite element method for solving scalar linear elliptic problems. Our main result is that these linear systems, which are symmetric and positive semidefinite, are well approximated by symmetric diagonally dominant matrices. Our framework for de. ning matrix approximation is support theory. Significant graph theoretic work has already been developed in the support framework for preconditioners in the diagonally dominant case, and, in particular, it is known that such systems can be solved with iterative methods in nearly linear time. Thus, our approximation result implies that these graph theoretic techniques can also solve a class of finite element problems in nearly linear time. We show that the support number bounds, which control the number of iterations in the preconditioned iterative solver, depend on mesh quality measures but not on the problem size or shape of the domain. C1 [Vavasis, Stephen] Univ Waterloo, Dept Combinator & Optimizat, Waterloo, ON N2L 2W2, Canada. [Boman, Erik G.] Sandia Natl Labs, Scalable Algorithms Dept, Albuquerque, NM 87185 USA. [Hendrickson, Bruce] Sandia Natl Labs, Dept Informat & Comp Sci, Albuquerque, NM 87185 USA. RP Vavasis, S (reprint author), Univ Waterloo, Dept Combinator & Optimizat, Waterloo, ON N2L 2W2, Canada. EM egboman@sandia.gov; bah@cs.sandia.gov; vavasis@math.uwaterloo.ca FU Applied Mathematical Sciences program; U. S. Department of Energy; Office of Energy Research; Lockheed Martin Company; U. S. Department of Energy's National Nuclear Security Administration [DE-AC94AL85000] FX This author's work was funded by the Applied Mathematical Sciences program, U. S. Department of Energy, Office of Energy Research and performed at Sandia National Labs, a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the U. S. Department of Energy's National Nuclear Security Administration under contract DE-AC94AL85000. NR 23 TC 13 Z9 13 U1 1 U2 10 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PY 2008 VL 46 IS 6 BP 3264 EP 3284 DI 10.1137/040611781 PG 21 WC Mathematics, Applied SC Mathematics GA 371RR UT WOS:000260849500020 ER PT J AU Romero, LA Mason, J AF Romero, Louis A. Mason, Jeff TI PITCHFORK BIFURCATIONS IN NONLINEAR LEAST SQUARES PROBLEMS-APPLICATIONS TO TOA GEOLOCATION SO SIAM JOURNAL ON OPTIMIZATION LA English DT Article DE bifurcations; nonlinear least squares; geolocation; TOA; TDOA; global positioning system AB We prove a general result concerning nonlinear least squares problems in the neighborhood of a singular Hessian. Assuming the Hessian has a one-dimensional null space, we show that in the neighborhood of such a point, there will be three solutions with small residuals. Counter to our intuition, assuming certain transversality conditions are satisfied, the solution with the largest residual is actually the most accurate solution. We illustrate this general theory by applying it to a time of arrival (TOA) geolocation problem. C1 [Romero, Louis A.] Sandia Natl Labs, Computat Math & Algorithms Dept, Albuquerque, NM 87123 USA. [Mason, Jeff] Sandia Natl Labs, Radar & Signal Anal Dept, Albuquerque, NM 87123 USA. RP Romero, LA (reprint author), Sandia Natl Labs, Computat Math & Algorithms Dept, MS 1320,POB 5800, Albuquerque, NM 87123 USA. EM lromero@sandia.gov; jjmason@sandia.gov FU US Department of Energy's National Nuclear Security Administration [DE-AC04-94AL85000] FX Received by the editors July 17, 2007; accepted for publication (in revised form) February 28, 2008; published electronically July 3, 2008. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. NR 10 TC 1 Z9 1 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1052-6234 J9 SIAM J OPTIMIZ JI SIAM J. Optim. PY 2008 VL 19 IS 2 BP 740 EP 755 DI 10.1137/070697598 PG 16 WC Mathematics, Applied SC Mathematics GA 371RS UT WOS:000260849600012 ER PT J AU Gavrea, BI Anitescu, M Potra, FA AF Gavrea, Bogdan I. Anitescu, Mihai Potra, Florian A. TI CONVERGENCE OF A CLASS OF SEMI-IMPLICIT TIME-STEPPING SCHEMES FOR NONSMOOTH RIGID MULTIBODY DYNAMICS SO SIAM JOURNAL ON OPTIMIZATION LA English DT Article DE rigid body; contact dynamics; friction; measure differential inclusion; complementarity problems ID BODY CONTACT PROBLEMS; GRANULAR SYSTEMS; COULOMB-FRICTION; SIMULATION; EXISTENCE; JOINTS; MODELS; WATER AB In this work we present a framework for the convergence analysis in a measure differential inclusion sense of a class of time-stepping schemes for multibody dynamics with contacts, joints, and friction. This class of methods solves one linear complementarity problem per step and contains the semi-implicit Euler method, as well as trapezoidal-like methods for which second-order convergence was recently proved under certain conditions. By using the concept of a reduced friction cone, the analysis includes, for the first time, a convergence result for the case that includes joints. An unexpected intermediary result is that we are able to de. ne a discrete velocity function of bounded variation, although the natural discrete velocity function produced by our algorithm may have unbounded variation. C1 [Gavrea, Bogdan I.] Tech Univ Cluj Napoca, Fac Automat & Comp Sci, RO-400027 Cluj Napoca, Romania. [Anitescu, Mihai] Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. [Potra, Florian A.] Univ Maryland Baltimore Cty, Dept Math & Stat, Baltimore, MD 21250 USA. RP Gavrea, BI (reprint author), Tech Univ Cluj Napoca, Fac Automat & Comp Sci, 26-28 Gh Baritiu St, RO-400027 Cluj Napoca, Romania. EM Bogdan.GAVREA@math.utcluj.ro; anitescu@mcs.anl.gov; potra@math.umbc.edu FU U. S. Department of Energy Office of Science laboratory [DE-AC02-06CH1135]; NSF [DMS-0139701, IIS-0413138]; Mathematical, Information, and Computational Sciences Division subprogram of the Office of Advanced Scientific Computing Research, Office of Science, U. S. Department of Energy [DE-AC02-06CH11357] FX Department of Mathematics and Statistics, University of Maryland-Baltimore County, Baltimore, MD 21250 (potra@math.umbc.edu). This author was supported at the University of Maryland-Baltimore County by NSF grant DMS-0139701. NR 51 TC 8 Z9 8 U1 1 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1052-6234 J9 SIAM J OPTIMIZ JI SIAM J. Optim. PY 2008 VL 19 IS 2 BP 969 EP 1001 DI 10.1137/060675745 PG 33 WC Mathematics, Applied SC Mathematics GA 371RS UT WOS:000260849600025 ER PT J AU Sala, M Tuminaro, RS AF Sala, Marzio Tuminaro, Raymond S. TI A NEW PETROV-GALERKIN SMOOTHED AGGREGATION PRECONDITIONER FOR NONSYMMETRIC LINEAR SYSTEMS SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE AMG; smoothed aggregation; nonsymmetric systems; fluid flow ID CONVERGENCE AB We propose a new variant of smoothed aggregation (SA) suitable for nonsymmetric linear systems. The new algorithm is based on two key generalizations of SA: restriction smoothing and local damping. Restriction smoothing refers to the smoothing of a tentative restriction operator via a damped Jacobi-like iteration. Restriction smoothing is analogous to prolongator smoothing in standard SA and in fact has the same form as the transpose of prolongator smoothing when the matrix is symmetric. Local damping refers to damping parameters used in the Jacobi-like iteration. In standard SA, a single damping parameter is computed via an eigenvalue computation. Here, local damping parameters are computed by considering the minimization of an energy-like quantity for each individual grid transfer basis function. Numerical results are given showing how this method performs on highly nonsymmetric systems. C1 [Sala, Marzio] BMW Sauber F1 Team, Hinwil, Switzerland. [Tuminaro, Raymond S.] Sandia Natl Labs, Livermore, CA 94551 USA. RP Sala, M (reprint author), BMW Sauber F1 Team, Hinwil, Switzerland. EM marzio.sala@gmail.com; tuminaro@ca.sandia.gov FU DOE Office of Science MICS Program; ASC Program at Sandia National Laboratories FX This work was partially supported by the DOE Office of Science MICS Program and by the ASC Program at Sandia National Laboratories. NR 32 TC 37 Z9 37 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 31 IS 1 BP 143 EP 166 DI 10.1137/060659545 PG 24 WC Mathematics, Applied SC Mathematics GA 403TD UT WOS:000263104000007 ER PT J AU Romero, LA Mason, J Day, DM AF Romero, Louis A. Mason, Jeff Day, David M. TI THE LARGE EQUAL RADIUS CONDITIONS AND TIME OF ARRIVAL GEOLOCATION ALGORITHMS SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE geolocation; time of arrival; Global Positioning System; Bancroft method; nonlinear least squares; minimum variance ID EQUATIONS; LOCATION AB We show that several methods for solving time of arrival (TOA) geolocation problems depend crucially on what we call the large equal radius (LER) conditions. For example, we analyze Bancroft's method and show that it works well assuming the LER conditions are satisfied. However, when these conditions are violated, we show that the method significantly deteriorates and does not achieve the minimum possible variance for a least squares solution. A direct method is also presented that finds all the critical points of the least squares functional. The method is found to perform well when the LER conditions are not satisfied but suffers from conditioning problems when they are satisfied. We also show that a simple but statistically inferior method that we call the reduced least squares (RLS) method deteriorates when the LER conditions are satisfied. C1 [Romero, Louis A.; Day, David M.] Sandia Natl Labs, Computat Math & Algorithms Dept, Albuquerque, NM 87185 USA. [Mason, Jeff] Sandia Natl Labs, Radar & Signal Anal Dept, Albuquerque, NM 87185 USA. RP Romero, LA (reprint author), Sandia Natl Labs, Computat Math & Algorithms Dept, MS 1320,POB 5800, Albuquerque, NM 87185 USA. EM lromero@sandia.gov; jjmason@sandia.gov; dmday@sandia.gov FU US Department of Energy's National Nuclear Security Administration [DE-AC04-94AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. NR 22 TC 2 Z9 2 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 31 IS 1 BP 254 EP 272 DI 10.1137/070699020 PG 19 WC Mathematics, Applied SC Mathematics GA 403TD UT WOS:000263104000011 ER PT J AU Bochev, PB Hu, JJ Siefert, CM Tuminaro, RS AF Bochev, Pavel B. Hu, Jonathan J. Siefert, Christopher M. Tuminaro, Raymond S. TI AN ALGEBRAIC MULTIGRID APPROACH BASED ON A COMPATIBLE GAUGE REFORMULATION OF MAXWELL'S EQUATIONS SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE Maxwell's equations; eddy currents; algebraic multigrid; multigrid; discrete Hodge Laplacian; compatible discretizations; edge elements ID 3D ELECTROMAGNETIC PROBLEMS; BOUNDARY-VALUE-PROBLEMS; SMOOTHED AGGREGATION; LORENTZ GAUGE; EDDY CURRENTS; CURL; DISCRETIZATIONS; FORMULATIONS; COMPUTATIONS; SIMULATION AB With the rise in popularity of compatible finite element, finite difference, and finite volume discretizations for the time domain eddy current equations, there has been a corresponding need for fast solvers of the resulting linear algebraic systems. However, the traits that make compatible discretizations a preferred choice for the Maxwell's equations also render these linear systems essentially intractable by truly black-box techniques. We propose an algebraic reformulation of the discrete eddy current equations along with a new algebraic multigrid (AMG) technique for this reformulated problem. The reformulation process takes advantage of a discrete Hodge decomposition on cochains to replace the discrete eddy current equations by an equivalent 2 x 2 block linear system whose diagonal blocks are discrete Hodge-Laplace operators acting on 1-cochains and 0-cochains, respectively. While this new AMG technique requires somewhat specialized treatment on the finest mesh, the coarser meshes can be handled using standard methods for Laplace-type problems. Our new AMG method is applicable to a wide range of compatible methods on structured and unstructured grids, including edge finite elements, mimetic finite differences, covolume methods, and Yee-like schemes. We illustrate the new technique, using edge elements in the context of smoothed aggregation AMG, and present computational results for problems in both two and three dimensions. C1 [Bochev, Pavel B.] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Hu, Jonathan J.; Tuminaro, Raymond S.] Sandia Natl Labs, Livermore, CA 94551 USA. [Siefert, Christopher M.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Bochev, PB (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM pbboche@sandia.gov; jhu@sandia.gov; csiefer@sandia.gov; rstumin@sandia.gov FU United States Department of Energy [DE-AC04-94-AL85000] FX Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94-AL85000. NR 50 TC 9 Z9 11 U1 0 U2 4 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 EI 1095-7197 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 31 IS 1 BP 557 EP 583 DI 10.1137/070685932 PG 27 WC Mathematics, Applied SC Mathematics GA 403TD UT WOS:000263104000022 ER PT J AU Lu, T Xu, ZL Samulyak, R Glimm, J Ji, XM AF Lu, T. Xu, Z. L. Samulyak, R. Glimm, J. Ji, X. M. TI Dynamic phase boundaries for compressible fluids SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE phase transition; conservative tracking ID CONSERVATIVE FRONT TRACKING; INTERFACE TRACKING; 3 DIMENSIONS; SIMULATION; LIQUID; VAPOR; COEFFICIENT; ALGORITHMS; FLOWS; WATER AB We present an algorithm for the simulation of a generalized Riemann problem for phase transitions in compressible fluids. We model the transition as a tracked jump discontinuity. The emphasis here is on the coupling of the phase transition process to acoustic waves, which is required for the study of cavitation induced by strong rarefaction waves. The robustness of the proposed algorithm is verified by application to various physical regimes. C1 [Lu, T.; Samulyak, R.] Brookhaven Natl Lab, Computat Sci Ctr, Upton, NY 11973 USA. [Xu, Z. L.] Univ Notre Dame, Dept Math, Notre Dame, IN 46556 USA. [Glimm, J.; Ji, X. M.] SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. RP Lu, T (reprint author), Brookhaven Natl Lab, Computat Sci Ctr, Upton, NY 11973 USA. EM tlu@nbl.gov; zxu2@nd.edu; rosamu@bnl.gov; glimm@ams.sunysb.edu; xji@ams.sunysb.edu RI Xu, Zhiliang/O-1718-2014 NR 33 TC 2 Z9 2 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 30 IS 2 BP 895 EP 915 DI 10.1137/060661703 PG 21 WC Mathematics, Applied SC Mathematics GA 280YA UT WOS:000254461500017 ER PT J AU Friedlander, MP Leyffer, S AF Friedlander, Michael P. Leyffer, Sven TI Global and finite termination of a two-phase augmented Lagrangian filter method for general quadratic programs SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE large-scale optimization; quadratic programming; gradient projection; active-set methods; filter methods; augmented Lagrangian ID ADAPTIVE PRECISION CONTROL; SADDLE-POINT PROBLEMS; NONLINEAR OPTIMIZATION; INDEFINITE SYSTEMS; SIMPLE BOUNDS; CONSTRAINED OPTIMIZATION; EQUALITY CONSTRAINTS; ALGORITHM; PRECONDITIONER; MINIMIZATION AB We present a two-phase algorithm for solving large-scale quadratic programs (QPs). In the first phase, gradient-projection iterations approximately minimize a bound-constrained augmented Lagrangian function and provide an estimate of the optimal active set. In the second phase, an equality-constrained QP defined by the current active set is approximately minimized in order to generate a second-order search direction. A filter determines the required accuracy of the subproblem solutions and provides an acceptance criterion for the search directions. The resulting algorithm is globally and finitely convergent. The algorithm is suitable for large-scale problems with many degrees of freedom, and provides an alternative to interior-point methods when iterative methods must be used to solve the underlying linear systems. Numerical experiments on a subset of the CUTEr QP test problems demonstrate the effectiveness of the approach. C1 [Friedlander, Michael P.] Univ British Columbia, Dept Comp Sci, Vancouver, BC V6T 1Z4, Canada. [Leyffer, Sven] Argonne Natl Lab, Mat & Comp Sci Div, Argonne, IL 60439 USA. RP Friedlander, MP (reprint author), Univ British Columbia, Dept Comp Sci, Vancouver, BC V6T 1Z4, Canada. EM mpf@cs.ubc.ca; leyffer@mcs.anl.gov NR 62 TC 10 Z9 10 U1 1 U2 5 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 30 IS 4 BP 1706 EP 1729 DI 10.1137/060669930 PG 24 WC Mathematics, Applied SC Mathematics GA 312YT UT WOS:000256709000003 ER PT J AU Griffin, JD Kolda, TG Lewis, RM AF Griffin, Joshua D. Kolda, Tamara G. Lewis, Robert Michael TI Asynchronous parallel generating set search for linearly constrained optimization SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE nonlinear programming; constrained optimization; linear constraints; direct search; derivative-free optimization; generalized pattern search; generating set search; asynchronous parallel optimization; asynchronous parallel pattern search ID PATTERN SEARCH; NONLINEAR OPTIMIZATION; MINIMIZATION; CONVERGENCE; ALGORITHM AB We describe an asynchronous parallel derivative-free algorithm for linearly constrained optimization. Generating set search (GSS) is the basis of our method. At each iteration, a GSS algorithm computes a set of search directions and corresponding trial points and then evaluates the objective function value at each trial point. Asynchronous versions of the algorithm have been developed in the unconstrained and bound-constrained cases which allow the iterations to continue (and new trial points to be generated and evaluated) as soon as any other trial point completes. This enables better utilization of parallel resources and a reduction in overall run time, especially for problems where the objective function takes minutes or hours to compute. For linearly constrained GSS, the convergence theory requires that the set of search directions conforms to the nearby boundary. This creates an immediate obstacle for asynchronous methods where the definition of nearby is not well defined. In this paper, we develop an asynchronous linearly constrained GSS method that overcomes this difficulty and maintains the original convergence theory. We describe our implementation in detail, including how to avoid function evaluations by caching function values and using approximate lookups. We test our implementation on every CUTEr test problem with general linear constraints and up to 1000 variables. Without tuning to individual problems, our implementation was able to solve 95% of the test problems with 10 or fewer variables, 73% of the problems with 11-100 variables, and nearly half of the problems with 100-1000 variables. To the best of our knowledge, these are the best results that have ever been achieved with a derivative-free method for linearly constrained optimization. Our asynchronous parallel implementation is freely available as part of the APPSPACK software. C1 [Griffin, Joshua D.; Kolda, Tamara G.] Sandia Natl Labs, Computat Sci & Mat Res Dept, Livermore, CA 94551 USA. [Lewis, Robert Michael] Coll William & Mary, Dept Mat, Williamsburg, VA 23187 USA. RP Griffin, JD (reprint author), Sandia Natl Labs, Computat Sci & Mat Res Dept, Livermore, CA 94551 USA. EM jgriffi@sandia.gov; tgkolda@sandia.gov; buckaroo@math.wm.edu RI Kolda, Tamara/B-1628-2009 OI Kolda, Tamara/0000-0003-4176-2493 NR 30 TC 15 Z9 15 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 30 IS 4 BP 1892 EP 1924 DI 10.1137/060664161 PG 33 WC Mathematics, Applied SC Mathematics GA 312YT UT WOS:000256709000011 ER PT J AU Pasciak, JE Vassilevski, PS AF Pasciak, Joseph E. Vassilevski, Panayot S. TI EXACT DE RHAM SEQUENCES OF SPACES DEFINED ON MACRO-ELEMENTS IN TWO AND THREE SPATIAL DIMENSIONS SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE mixed finite elements; exact sequences; algebraic multigrid; composite elements; agglomeration ID INTERPOLATION; AGGLOMERATION; H(DIV) AB This paper proposes new finite element spaces that can be constructed for agglomerates of standard elements that have certain regular structure. The main requirement is that the agglomerates share faces that have closed boundaries composed of 1-d edges. The spaces resulting from the agglomerated elements are subspaces of the original de Rham sequence of H(1)-conforming, H(curl)-conforming, H(div)-conforming, and piecewise constant spaces associated with an unstructured "fine" mesh. The procedure can be recursively applied so that a sequence of nested de Rham complexes can be constructed. As an illustration we generate coarser spaces from the sequence corresponding to the lowest-order Nedelec spaces, lowest-order Raviart-Thomas spaces, and for piecewise linear H(1)-conforming spaces, all in three dimensions. The resulting V-cycle multigrid methods used in preconditioned conjugate gradient iterations appear to perform similar to those of the geometrically refined case. C1 [Pasciak, Joseph E.] Texas A&M Univ, Dept Math, College Stn, TX 77843 USA. [Vassilevski, Panayot S.] Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Pasciak, JE (reprint author), Texas A&M Univ, Dept Math, MS 3368,Blocker Hall, College Stn, TX 77843 USA. EM pasciak@math.tamu.edu; vassilevski1@llnl.gov FU U.S. Department of Energy by Lawrence Livermore National Laboratory [DE-AC52-07NA27344] FX This work supported by the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. NR 20 TC 15 Z9 15 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 30 IS 5 BP 2427 EP 2446 DI 10.1137/070698178 PG 20 WC Mathematics, Applied SC Mathematics GA 371RW UT WOS:000260850000011 ER PT J AU Tartakovsky, AM Tartakovsky, DM Scheibe, TD Meakin, P AF Tartakovsky, A. M. Tartakovsky, D. M. Scheibe, T. D. Meakin, P. TI HYBRID SIMULATIONS OF REACTION-DIFFUSION SYSTEMS IN POROUS MEDIA SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article; Proceedings Paper CT SIAM Conference on Computational Science and Engineering CY FEB 19-23, 2007 CL Costa Mesa, CA SP SIAM DE multiphysics; multiscale; multiresolution; reactive transport; subsurface ID SMOOTHED PARTICLE HYDRODYNAMICS; PARTIAL-DIFFERENTIAL-EQUATIONS; ALGORITHM REFINEMENT AB Hybrid or multiphysics algorithms provide an efficient computational tool for combining micro- and macroscale descriptions of physical phenomena. Their use becomes imperative when microscale descriptions are too computationally expensive to be conducted in the whole domain, while macroscale descriptions fail in a small portion of the computation domain. We present a hybrid algorithm to model a general class of reaction-diffusion processes in granular porous media, which includes mixing-induced mineral precipitation on, or dissolution of, the porous matrix. These processes cannot be accurately described using continuum (Darcy-scale) models. The pore-scale/Darcy-scale hybrid is constructed by coupling solutions of the reaction-diffusion equations (RDE) at the pore scale with continuum Darcy-level solutions of the averaged RDEs. The resulting hybrid formulation is solved numerically by employing a multiresolution meshless discretization based on the smoothed particle hydrodynamics method. This ensures seamless noniterative coupling of the two components of the hybrid model. Computational examples illustrate the accuracy and efficiency of the hybrid algorithm. C1 [Tartakovsky, A. M.; Scheibe, T. D.] Pacific NW Natl Lab, Richland, WA 99352 USA. [Tartakovsky, D. M.] Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA. [Meakin, P.] Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Tartakovsky, AM (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM alexandre.tartakovsky@pnl.gov; dmt@ucsd.edu; tim.scheibe@pnl.gov; paul.meakin@inl.gov RI Scheibe, Timothy/A-8788-2008; Tartakovsky, Daniel/E-7694-2013 OI Scheibe, Timothy/0000-0002-8864-5772; NR 19 TC 52 Z9 52 U1 0 U2 15 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PY 2008 VL 30 IS 6 SI SI BP 2799 EP 2816 DI 10.1137/070691097 PG 18 WC Mathematics, Applied SC Mathematics GA 371RY UT WOS:000260850200006 ER PT S AU Loveland, RC Rosten, E Porter, R AF Loveland, Rohan C. Rosten, Edward Porter, Reid BE Drummond, OE TI Improving multiple target tracking in structured environments using velocity priors SO SIGNAL AND DATA PROCESSING OF SMALL TARGETS 2008 SE Proceedings of SPIE LA English DT Proceedings Paper CT 20th Conference on Signal and Data Processing of Small Targets CY MAR 18-20, 2008 CL Orlando, FL SP SPIE DE tracking; video; traffic; urban; transportation AB In this paper, we present an algorithm for determining a velocity probability distribution prior from low frame rate aerial video of an urban area, and show how this may be used to aid in the multiple target tracking problem, as well as to provide a foundation for the automated classification of urban transportation infrastructure. The algorithm used to develop the prior is based on using a generic interest point detector to find automobile candidate locations, followed by a series of filters based on scale and motion to reduce the number of false alarms. The remaining locations are then associated between frame pairs using a simple matching algorithm, and the corresponding tracks are then used to build up velocity histograms in the areas that are moved through between the track endpoints. The algorithm is tested on a dataset taken over urban Tucson. AZ. The results demonstrate that the velocity probability distribution prior can be used to infer a variety of information about road lane directions, speed limits, etc..., as well as providing a means of describing environmental knowledge about traffic rules that can be used in tracking. C1 [Loveland, Rohan C.; Rosten, Edward; Porter, Reid] Los Alamos Natl Lab, Los Alamos, NM USA. RP Loveland, RC (reprint author), Los Alamos Natl Lab, Los Alamos, NM USA. EM rohan@lanl.gov NR 7 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7160-4 J9 PROC SPIE PY 2008 VL 6969 AR 69690H DI 10.1117/12.775859 PG 8 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA BIA85 UT WOS:000257982200014 ER PT S AU Porter, R Fraser, A Loveland, R Rosten, E AF Porter, R. Fraser, A. Loveland, R. Rosten, E. BE Drummond, OE TI A recurrent velocity filter for detecting large numbers of moving objects SO SIGNAL AND DATA PROCESSING OF SMALL TARGETS 2008 SE Proceedings of SPIE LA English DT Proceedings Paper CT 20th Conference on Signal and Data Processing of Small Targets CY MAR 18-20, 2008 CL Orlando, FL SP SPIE DE multi-target tracking; moving object detection; wide-area video AB We present a method for detecting a large number of moving targets, such as cars and people, in geographically referenced video. The problem is difficult, due to the large and variable number of targets which enter and leave the field of view, and due to imperfect geo-projection and registration. In our method, we assume feature extraction produces a collection of candidate locations (points in 2D space) for each frame. Some of these locations are real objects, but many are false alarms. Typical feature extraction might be frame differencing, or target recognition. For each candidate location, and at each time step, our algorithm outputs a velocity estimate and confidence which can be thresholded to detect objects with constant velocity. In this paper we derive the algorithm, investigate the free parameters, and compare its performance to a multi-target tracking algorithm. C1 [Porter, R.; Fraser, A.; Loveland, R.; Rosten, E.] Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, Los Alamos, NM 87545 USA. RP Porter, R (reprint author), Los Alamos Natl Lab, Space & Remote Sensing Sci Grp, POB 1663, Los Alamos, NM 87545 USA. EM rporter@lanl.gov NR 6 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7160-4 J9 PROC SPIE PY 2008 VL 6969 AR 69690C DI 10.1117/12.778505 PG 9 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA BIA85 UT WOS:000257982200010 ER PT J AU Wohlberg, B Brislawn, CM AF Wohlberg, Brendt Brislawn, Christopher M. TI Symmetric extension for lifted filter banks and obstructions to reversible implementation SO SIGNAL PROCESSING LA English DT Article DE filter bank; symmetric extension; lifting; reversible; JPEG 2000 ID WAVELET TRANSFORMS; COMPRESSION; REPRESENTATION AB Symmetric pre-extension is a standard approach to boundary handling for finite-length input vectors with linear phase filter banks. It works with both conventional linear implementations and the so-called reversible, or integer-to-integer, implementations of odd-length linear phase (whole-sample symmetric) filter banks. In comparison, significant difficulties arise when using symmetric pre-extension on reversible filter banks with even-length (ha f-sample symmetric) linear phase filters. An alternative approach is presented using lifting step extension, in which boundary extensions are performed in each step of a lifting factorization, avoiding some of these difficulties while preserving reversibility and retaining the nonexpansive property of symmetric pre-extension. Another alternative that is capable of preserving both reversibility and subband symmetry for half-sample symmetric filter banks is developed based on ideas from the theory of lattice vector quantization. The practical ramifications of this work are illustrated by describing its influence on the specification of filter bank algorithms in Part 2 of the ISOJEC JPEG 2000 image coding standard. Published by Elsevier B.V. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wohlberg, B (reprint author), Los Alamos Natl Lab, T-7 Math Modeling & Anal,MS-B284, Los Alamos, NM 87545 USA. EM brendt@t7.lanl.gov; brislawn@lanl.gov RI Wohlberg, Brendt/M-7764-2015 OI Wohlberg, Brendt/0000-0002-4767-1843 NR 29 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-1684 J9 SIGNAL PROCESS JI Signal Process. PD JAN PY 2008 VL 88 IS 1 BP 131 EP 145 DI 10.1016/j.sigpro.2007.07.010 PG 15 WC Engineering, Electrical & Electronic SC Engineering GA 221OL UT WOS:000250237100010 ER PT S AU Brodsky, SJ de Teramond, GF Shrock, R AF Brodsky, Stanley J. de Teramond, Guy F. Shrock, Robert BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Light-Front Holography and Hadronization at the Amplitude Level SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE AdS/CFT; QCD; Holography; Light-Front Wavefunctions; Condensates; Hadronization ID QUANTUM CHROMODYNAMICS; WAVE-FUNCTION; MOMENTUM; BAG; SUPERGRAVITY; INVARIANCE; SYMMETRY; NUCLEON; MODEL; SPIN AB The correspondence between theories in anti-de Sitter space and conformal field theories in physical space-time leads to an analytic, semiclassical model for strongly-coupled QCD which has scale invariance at short distances and color confinement at large distances. Light-front holography is a remarkable feature of AdS/CFT: it allows hadronic amplitudes in the Ads fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. Some novel features of QCD are discussed, including the consequences of confinement for quark and gluon condensates and the behavior of the QCD coupling in the infrared. We suggest that the spatial support of QCD condensates is restricted to the interior of hadrons, since they arise due to the interactions of confined quarks and gluons. Chiral symmetry is thus broken in a limited domain of size 1/m pi,, in analogy to the limited physical extent of superconductor phases. A new method for computing the hadronization of quark and gluon jets at the amplitude level, an event amplitude generator, is outlined. C1 [Brodsky, Stanley J.] Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. [Brodsky, Stanley J.] Inst Particle Phys & Phenomenol, Durham, England. [de Teramond, Guy F.] Univ Costa Rica, San Jose, Costa Rica. [Shrock, Robert] SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. RP Brodsky, SJ (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. FU Department of Energy [DE-AC02-76SF00515, NSF-PHY-06-53342.] FX Presented by SJB at the Sixth International Conference on Perspectives in Hadronic Physics, 12 - 16 May 2008, Miramare - Trieste, Italy. He also thanks the Institute for Particle Physics Phenomenology, Durham, UK for its hospitality. This research was supported by the Department of Energy contract DE-AC02-76SF00515 and NSF-PHY-06-53342. Pub numbers: SLAC-PUB-13306, 51DCPT/08/102, YITP-SB-08-33. NR 37 TC 18 Z9 18 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 3 EP + PG 2 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900001 ER PT S AU Thomas, AW AF Thomas, Anthony W. BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Invariant Spin in the Proton SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE spin structure of the proton; strange quark spin; orbital angular momentum; anomaly ID DEPENDENT PARTON DISTRIBUTIONS; BAG MODEL; DELTA-G/G; NUCLEON; ASYMMETRY; DEUTERON; HADRONS; HERMES; REGION; SEA AB We discuss recent theoretical progress in understanding the distribution of spin and orbital angular momentum in the proton. particular attention is devoted to the effect of QCD evolution and to the distinction between "chiral" and "invariant" spin. This is particularly significant with respect to the possible presence of polarized strange quarks. C1 [Thomas, Anthony W.] Jefferson Lab, Newport News, VA 23606 USA. RP Thomas, AW (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. OI Thomas, Anthony/0000-0003-0026-499X NR 50 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 39 EP 46 PG 8 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900005 ER PT S AU Gaskell, D AF Gaskell, D. CA JLab E03-103 Collaboration BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI New Measurements of the EMC Effect in Light Nuclei and at Large x SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium ID QUARK-HADRON DUALITY; ELECTRON-SCATTERING; DEPENDENCE; DEUTERIUM AB The modification of structure functions in nuclei (the EMC effect) has been the focus of intense experimental and theoretical study since the original observation in 1983. The EMC effect unequivocally demonstrates that quark distributions in nuclei are not simply the incoherent sum of the nucleon quark distributions. However, progress in understanding the root cause of these modifications has been hampered by the complexity of nuclear structure, making it difficult to disentangle the "conventional" nuclear effects of Fermi motion and binding from true medium modifications to nucleon structure. Experiment E03-103 at Jefferson Lab made measurements of nuclear structure function ratios from few-body nuclei ((3)He and (4)He) to deuterium; where the nuclear structure is well known, and for a range of nuclei. A=3 to 197, at large x, where effects front Fermi motion and binding dominate. C1 [Gaskell, D.; JLab E03-103 Collaboration] Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Gaskell, D (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 148 EP 155 PG 8 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900019 ER PT S AU Venugopalan, R AF Venugopalan, Raju BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Factorization, the Glasma and the Ridge in heavy ion collisions SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE Color Glass Condensate; Factorization; Glasma; Ridge ID GLUON DISTRIBUTION-FUNCTIONS; NUCLEAR COLLISIONS; ELLIPTIC FLOW; HIGH-ENERGIES; CONDENSATE; DENSITY; FIELD; QCD; EVOLUTION; EQUATION AB High energy heavy ion collisions can be efficiently described as the. collision of two sheets of Color Glass Condensate. The dynamics of the collision can be studied ab initio in a systematic effective field theory approach. This requires factorization theorems that separate the initial state evolution of the wave functions with energy front the final state interactions that produce matter with high energy densities called the Glasma. We discuss how this matter is formed, its remarkable properties and its relevance for understanding thermalization of the Quark Gluon Plasma in heavy ion collisions. Long range rapidity correlations in the collision that have a remarkable ridge like structure may allow us to probe early times in the collision and infer directly the properties of the Glasma. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Venugopalan, R (reprint author), Brookhaven Natl Lab, Dept Phys, Bldg 510A, Upton, NY 11973 USA. NR 73 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 164 EP 169 PG 6 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900021 ER PT S AU Brooks, W Hakobyan, H AF Brooks, Will Hakobyan, Hayk BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Studies of Parton Propagation and Hadron Formation in the Space-Time Domain SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE QCD; nuclei; nuclear; parton; characteristic time; hadronization AB Over the past decade, new data from HERMES, Jefferson Lab. Fermilab, and RHIC that connect to parton propagation and hadron formation have become available. Semi-inclusive DIS on nuclei, the Drell-Yan reaction, and heavy-ion collisions all brine different kinds of information on parton propagation within a medium, while the most direct information on hadron formation comes from the DIS data. Over the next decade one can hope to begin to understand these data within a unified picture. We briefly Survey the most relevant data and the common elements of the physics picture, then highlight the new Jefferson Lab data, and close with a prospective for the future. C1 [Brooks, Will] Univ Tecn Federico Santa Maria, Dept Fis, Avda Espana 1680,Casilla 110-V, Valparaiso, Chile. [Brooks, Will] Univ Tecn Federico Santa Maria, Ctr Estudios Subatomicos, Valparaiso, Chile. [Hakobyan, Hayk] Yerevan State Univ, Dept Phys, Yerevan 375049, Armenia. [Hakobyan, Hayk] Yerevan Phys Inst, Dept Phys, Yerevan 375036, Armenia. [Brooks, Will; Hakobyan, Hayk] Thomas Jefferson Natl Accelerator Facil, Div Phys, Newport News, VA 23606 USA. RP Brooks, W (reprint author), Univ Tecn Federico Santa Maria, Dept Fis, Avda Espana 1680,Casilla 110-V, Valparaiso, Chile. NR 13 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 215 EP + PG 2 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900028 ER PT S AU Nasseripour, R Djalali, C Wood, M Weygand, D AF Nasseripour, R. Djalali, C. Wood, M. Weygand, D. BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Medium Modification of the Light Vector Mesons in Nuclei SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE vector meson; medium modification; chiral symmetry ID AU COLLISIONS; RHO-MESON; PHI-PHOTOPRODUCTION; MATTER; DEPENDENCE; HOT AB Theoretical calculations predict the modification of properties of vector mesons, such as a shift in their masses and/or broadening of their widths in dense nuclear matter. These effects can be. related to partial restoration of chiral symmetry at high density or temperature. Photoproduction of sector mesons off nuclei were performed at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). The data were taken with a beam of tagged photons with energies up to 4 GeV on various nuclear targets. The properties of the rho vector mesons were investigated via their rare leptonic decay to e+e-. This decay channel is preferred over hadronic modes in order to eliminate final state interactions in the nuclear matter. The combinatorial background in the. mass spectrum was removed by a self-normalizing mixed-event technique. The rho meson mass distributions were extracted for each of the taragets. Statistically significant results regarding medium modification of the rho meson in the nuclear medium rule out large medium effects. Transparency studies of the omega and phi vector mesons allows a determination of their widths in the medium. C1 [Nasseripour, R.] George Washington Univ, Washington, DC 20052 USA. [Djalali, C.; Wood, M.] Univ South Carolina, Columbia, SC 29208 USA. [Weygand, D.] Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Nasseripour, R (reprint author), George Washington Univ, Washington, DC 20052 USA. FU U.S. Department of Energy; National Science Foundation; United States Department of Energy [DE-AC05-06OR23177] FX The authors would like to thank U. Mosel, P. Muehlich, J. Weil, O. Buss, and A. Afanasev for providing us with theoretical support during this work. The U.S. Department of Energy and the National Science Foundation supported this work. The Jefferson Science Associates, LLC, operates the Thomas Jefferson National Accelerator Facility for the United States Department of Energy under contract No. DE-AC05-06OR23177. NR 41 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 223 EP + PG 2 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900029 ER PT S AU Piasetzky, E Pomerantz, I Higinbotham, D Strauch, S Gilman, R AF Piasetzky, Eli Pomerantz, Ishay Higinbotham, D. Strauch, S. Gilman, R. CA Expt E03-101 Hall AJ Lab Collabora BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Hard Photodisintegration of Proton Pairs in He-3 SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE Hard photodisintegration ID LARGE MOMENTUM-TRANSFER; 2-BODY PHOTODISINTEGRATION; DEUTERON PHOTODISINTEGRATION; ELASTIC-SCATTERING; PHOTONS AB Hard deuteron photodisintegration has been investigated for 20 years, as its cross section follows the constituent counting rule and it provides insight into the interplay between hadronic and quark-gluon degrees of freedom in high-momentum transfer exclusive reactions. We have now measured for the first time hard pp-pair disintegration in the reaction gamma He-3 -> pp + n, using kinematics corresponding to a spectator neutron. Cross sections were measured for 90 degrees c.m. at 8 beam energies, from 0.8 to 4.7 GeV. Preliminary results will be presented and compared to the hard deuteron photodisintegration data. C1 [Piasetzky, Eli; Pomerantz, Ishay] Tel Aviv Univ, IL-69978 Tel Aviv, Israel. [Higinbotham, D.; Gilman, R.] Jefferson Lab, Newport News, VA 23606 USA. [Strauch, S.] Univ South Carolina, Columbia, SC 29208 USA. [Gilman, R.] Rutgers State Univ, Piscataway, NJ 08855 USA. RP Piasetzky, E (reprint author), Tel Aviv Univ, IL-69978 Tel Aviv, Israel. RI Higinbotham, Douglas/J-9394-2014 OI Higinbotham, Douglas/0000-0003-2758-6526 FU Department of Energy [DE-AC03-76SF00515]; Southeastern Universities Research Association operates; Thomas Jefferson National Accelerator Facility under US DOE [DE-AC05-84ER40150]; US National Science Foundation [PHY-00-98642]; US DOE [DE-FG02-98ER41087, DE-FG03-97ER41014, DE-FG02-01ER-41172]; Israel Science Foundation; Israel Academy of Science; Humanities FX We thank A. Radyushkin and L. Kondratyuk for useful discussions. The Stanford Linear Accelerator (supporting in part S.J.B.) is funded by the Department of Energy under Contract No. DE-AC03-76SF00515. The Southeastern Universities Research Association operates the Thomas Jefferson National Accelerator Facility (supporting in part S.J.B., R.G. and M.S.) under US DOE Contract DE-AC05-84ER40150. R.G. acknowledges the support of the US National Science Foundation, grant PHY-00-98642. J.R.H. acknowledges the support of the US DOE under Contract DE-FG02-98ER41087. G.A.M. acknowledges the support of the US DOE under Contract DE-FG03-97ER41014. E.P. is supported by the Israel Science Foundation founded by the Israel Academy of Science and Humanities. M.S. acknowledges the support of the US DOE under Contract DE-FG02-01ER-41172. NR 31 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 280 EP + PG 2 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900036 ER PT S AU Higinbotham, DW AF Higinbotham, Douglas W. BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Short-Range Structure of Nuclei SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE short-range correlations AB The nucleons in a nucleus can form short-range correlated pairs. A recent Jefferson Lab electron scattering experiment. where a proton was knocked-out of the nucleus with high momentum transfer and high missing momentum, has shown that in (12)C the neutron-Proton pairs are nearly twenty times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs has been shown to be due to the short-range tensor part of the nucleon-nucleon interaction. C1 Jefferson Lab, Newport News, VA 23601 USA. RP Higinbotham, DW (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23601 USA. RI Higinbotham, Douglas/J-9394-2014 OI Higinbotham, Douglas/0000-0003-2758-6526 NR 23 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 301 EP 306 PG 6 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900039 ER PT S AU Burkert, VD AF Burkert, Volker D. BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Electromagnetic Transition Form Factors of Nucleon Resonances. SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE Electromagnetic Form Factors ID ROPER RESONANCE; QUARK-MODEL; ELECTROPRODUCTION; QCD; BARYONS AB Recent measurements of nucleon resonance transition form factors with CLAS at Jefferson Lab are discussed. The new data resolve a long-standing puzzle of the nature of the Roper resonance, and confirm the assertion of the symmetric constituent quark model of the Roper as the first radial excitation of the nucleon. The data on high Q(2) n pi(+) production confirm the slow fall off of the S(11) (1535) transition form factor with Q(2), and better constrain the branching ratios beta(N pi) = 0.50 and beta(N eta) = 0.45. For the first time. the longitudinal transition amplitude to the S(11) (1535) was extracted from the n pi(+) data. Also. new results on the transition amplitudes for the D(13)(1520) resonance are presented showing a rapid transition from helicity 3/2 dominance seen at the real photon point to helicty 1/2 dominance at higher Q(2). C1 Jefferson Lab, Newport News, VA 23606 USA. RP Burkert, VD (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. EM burkert@jlab.org NR 48 TC 10 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 348 EP 356 PG 9 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900045 ER PT S AU Wojtsekhowski, B AF Wojtsekhowski, B. BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Nucleon Form Factors experiments with 12 GeV CEBAF SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE Nucleon Form Factors ID GENERALIZED PARTON DISTRIBUTIONS; VIRTUAL COMPTON-SCATTERING; POLARIZATION TRANSFER; MOMENTUM-TRANSFER; CROSS-SECTIONS; ELECTRON AB A number of precision form factor experiments at high momentum transfer will be performed with the 11 GeV electron beam of CEBAF We review the approved proposals and the conceptual schemes of several new suggestions. Form factor data will serve as a major input for the construction of a tomographic image of the nucleon. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Wojtsekhowski, B (reprint author), Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. NR 37 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 365 EP 371 PG 7 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900047 ER PT S AU de Jager, K AF de Jager, Kees BE Boffi, S DegliAtti, CC Giannini, M Treleani, D TI Neutron Spin Structure Studies and Low-Energy Tests of the Standard Model at JLab SO SIXTH INTERNATIONAL CONFERENCE ON PERSPECTIVES IN HADRONIC PHYSICS SE AIP Conference Proceedings LA English DT Proceedings Paper CT 6th International Conference on Perspectives in Hadronic Physics CY MAY 12-16, 2008 CL Trieste, ITALY SP ICTP, Natl Inst Nucl Phys, Univ Perugia, Univ Genoa, Phys Consortium DE neutron spin structure; parity violation; Standard Model Tests ID SUM-RULE; RESONANCE; REGION AB The most recent results on the spin structure of the neutron from Hall A are presented and discussed. Then, an overview is given of various experiments planned with the 12 GeV upgrade at Jefferson Lab to provide sensitive tests of the Standard Model at relatively low energies. C1 Jefferson Lab, Newport News, VA 23606 USA. RP de Jager, K (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 978-0-7354-0586-8 J9 AIP CONF PROC PY 2008 VL 1056 BP 412 EP 419 PG 8 WC Physics, Applied; Physics, Nuclear SC Physics GA BIM79 UT WOS:000260919900053 ER PT J AU Wang, J Liu, GD Wu, H Lin, YH AF Wang, Jun Liu, Guodong Wu, Hong Lin, Yuehe TI Quantum-dot-based electrochemical immunoassay for high-throughput screening of the prostate-specific antigen SO SMALL LA English DT Article DE antigens; electrochemical methods; high-throughput screening; immunoassays; quantum dots ID NANOPARTICLE LABELS; CANCER BIOMARKERS; BIOASSAY LABELS; TUMOR-MARKERS; DIAGNOSTICS; ASSAY; PSA; NANOTECHNOLOGY; NANOVEHICLES; PROTEINS C1 [Wang, Jun; Liu, Guodong; Wu, Hong; Lin, Yuehe] Pacific NW Natl Lab, Richland, WA 99354 USA. RP Lin, YH (reprint author), Pacific NW Natl Lab, Richland, WA 99354 USA. EM yuehe.lin@pnl.gov RI Lin, Yuehe/D-9762-2011 OI Lin, Yuehe/0000-0003-3791-7587 FU NIEHS NIH HHS [U54 ES16015]; NINDS NIH HHS [NS058161-01] NR 34 TC 86 Z9 87 U1 0 U2 18 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1613-6810 J9 SMALL JI Small PD JAN PY 2008 VL 4 IS 1 BP 82 EP 86 DI 10.1002/smll.200700459 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 271GY UT WOS:000253778100012 PM 18081131 ER PT J AU Lee, J Lee, Y Youn, JK Bin Na, H Yu, T Kim, H Lee, SM Koo, YM Kwak, JH Park, HG Chang, HN Hwang, M Park, JG Kim, J Hyeon, T AF Lee, Jinwoo Lee, Youjin Youn, Jong Kyu Bin Na, Hyon Yu, Taekyung Kim, Hwan Lee, Sang-Mok Koo, Yoon-Mo Kwak, Ja Hun Park, Hyun Gyu Chang, Ho Nam Hwang, Misun Park, Je-Geun Kim, Jungbae Hyeon, Taeghwan TI Simple synthesis of functionalized superparamagnetic magnetite/silica core/shell nanoparticles and their application as magnetically separable high-performance biocatalysts SO SMALL LA English DT Article DE core/shell materials; iron oxides; silica; superparamagnetism; surface functionalization ID HISTIDINE-TAGGED PROTEINS; MESOPOROUS SILICA; COBALT NANORODS; NANOCRYSTALS; NANOCOMPOSITES; SIZE; CRYSTALLINE; SEPARATION; SHAPE; WATER AB Uniformly sized silica-coated magnetic nanoparticles (magnetite@silica) are synthesized in a simple one-pot process using reverse micelles as nanoreactors. The core diameter of the magnetic nanoparticles is easily controlled by adjusting the w value ([polar solvent]/[surfactant]) in the reverse-micelle solution, and the thickness of the silica shell is easily controlled by varying the amount of tetraethyl orthosilicate added after the synthesis of the magnetite cores. Several grams of monodisperse magnetite@silica nanoparticles can be synthesized without going through any size-selection process. When crosslinked enzyme molecules form clusters on the surfaces of the magnetite@silica nanoparticles, the resulting hybrid composites are magnetically separable, highly active, and stable under harsh shaking conditions for more than 15 days. Conversely, covalently attached enzymes on the surface of the magnetite@silica nanoparticles are deactivated under the same conditions. C1 [Lee, Jinwoo; Lee, Youjin; Bin Na, Hyon; Yu, Taekyung; Kim, Hwan; Hyeon, Taeghwan] Seoul Natl Univ, Sch Chem Engn, Seoul 151744, South Korea. [Lee, Jinwoo; Lee, Youjin; Bin Na, Hyon; Yu, Taekyung; Kim, Hwan; Hyeon, Taeghwan] Seoul Natl Univ, Natl Creat Res Initiat Ctr Oxide Nanocrystalline, Seoul 151744, South Korea. [Youn, Jong Kyu; Park, Hyun Gyu; Chang, Ho Nam] Korea Adv Inst Sci & Technol, Dept Chem & Biomol Engn, Taejon 305701, South Korea. [Lee, Sang-Mok; Koo, Yoon-Mo] Inha Univ, Ctr Adv Bioseperat Technol, Inchon 402751, South Korea. [Hwang, Misun; Park, Je-Geun] Sungkyunkwan Univ, Dept Phys, Suwon 440746, South Korea. [Kwak, Ja Hun; Kim, Jungbae] Pacific NW Natl Lab, Richland, WA 99352 USA. EM jungbae.Kim@pnl.gov; thyeon@snu.ac.kr RI PARK, HYUN GYU/C-1597-2011; Chang, HN/B-9351-2011; Hyeon, Taeghwan/J-5315-2012; Park, Je Geun/K-8571-2013; Kwak, Ja Hun/J-4894-2014; Lee, Jinwoo/G-3330-2016; Lee, Junyoung/D-5463-2012 OI Lee, Jinwoo/0000-0001-6347-0446; Lee, Junyoung/0000-0001-6689-2759 NR 51 TC 243 Z9 245 U1 27 U2 195 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 1613-6810 J9 SMALL JI Small PD JAN PY 2008 VL 4 IS 1 BP 143 EP 152 DI 10.1002/smll.200700456 PG 10 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 271GY UT WOS:000253778100022 PM 18189246 ER PT S AU Rumsey, MA Paquette, JA AF Rumsey, Mark A. Paquette, Joshua A. BE Ecke, W Peters, KJ Meyendorf, NG TI Structural health monitoring of wind turbine blades - art. no. 69330E SO SMART SENSOR PHENOMENA, TECHNOLOGY, NETWORKS, AND SYSTEMS 2008 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Smart Sensor, Phenomena, Technology, Networks, and Systems CY MAR 10-12, 2008 CL San Diego, CA SP SPIE, Amer Soc Mech Engineers, Intelligent Mat Forum, Jet Propuls Lab, Natl Sci Fdn DE wind turbine blades; fatigue testing; acoustic emission; macro-fiber composite AB As electric utility wind turbines increase in size, and correspondingly, increase in initial capital investment cost, there is an increasing need to monitor the health of the structure. Acquiring an early indication of structural or mechanical problems allows operators to better plan for maintenance, possibly operate the machine in a de-rated condition rather than taking the unit off-line, or in the case of an emergency, shut the machine down to avoid further damage. This paper describes several promising structural health monitoring (SHM) techniques that were recently exercised during a fatigue test of a 9 meter glass-epoxy and carbon-epoxy wind turbine blade. The SHM systems were implemented by teams from NASA Kennedy Space Center, Purdue University and Virginia Tech. A commercial off-the-shelf acoustic emission (AE) NDT system gathered blade AE data throughout the test. At a fatigue load cycle rate around 1.2 Hertz, and after more than 4,000,000 fatigue cycles, the blade was diagnostically and visibly failing at the out-board blade spar-cap termination point at 4.5 meters. For safety reasons, the test was stopped just before the blade completely failed. This paper provides an overview of the SHM and NDT system setups and some current test results. C1 [Rumsey, Mark A.; Paquette, Joshua A.] Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Rumsey, MA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 28 TC 8 Z9 8 U1 0 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 978-0-8194-7119-2 J9 P SOC PHOTO-OPT INS PY 2008 VL 6933 BP E9330 EP E9330 DI 10.1117/12.778324 PG 15 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Engineering, Mechanical; Remote Sensing; Optics SC Computer Science; Engineering; Remote Sensing; Optics GA BHW84 UT WOS:000257108400011 ER PT B AU Robertson, SW Ritchie, RO Mehta, A Gong, XY Pelton, AR AF Robertson, Scott W. Ritchie, Robert O. Mehta, Apurva Gong, Xiao-Yan Pelton, Alan R. BE Berg, B Mitchell, MR Proft, J TI Ultrahigh-Resolution In Situ Diffraction Characterization of the Local Mechanics at a Growing Crack Tip in Nitinol SO SMST 2006: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON SHAPE MEMORY AND SUPERELASTIC TECHNOLOGIES LA English DT Proceedings Paper CT International Conference on Shape Memory and Superelastic Technologies CY MAY 07-11, 2006 CL Pacific Grove, CA SP Admedes Schussler GmbH, Boston Sci, Dearborn Precis Tubular Prod, Edwards Lifesciences, Ft Wayne Met Res Prod Corp, Guidant Endovasc Solut, Johnson Matthey, Kemac Technologies, Mech & Mat Consulting, Medtron Vasc, MeKo Laser Mat Proc, Memry Corp, Minitubes, Nitinol Devices & components, SAES Getters Grp, Special Met Corp, Shape Mem Alloys Div, Ulbrich Stainless Steels & Special Met ID SHAPE-MEMORY ALLOYS; TRANSFORMATION; PROPAGATION AB Despite the recognized importance of the in vivo fatigue properties of Nitinol, there is still limited understanding of how fatigue cracks propagate in this material. This study represents an initial approach to gain such understanding via a combination of fracture-mechanics testing and synchrotron x-ray (micro) diffraction, by providing insight into the role of transformational and local strain fields on the progression of fracture in a stent-like material structure. The results presented here compare the fracture-mechanics predicted transformation-zone size and shape with the actual zones measured by micro-diffraction. Tests were conducted with compact-tension specimens, laser-cut from Nitinol tube that was shape-set flat; this configuration mimics the microstructure and texture observed in Nitinol medical devices. Fatigue cracks were grown ex situ at near-threshold conditions (Delta K = 3 MPa root m) to a crack length to sample width ratio of a/W = 0.5. Specimens were then loaded in situ with a miniature straining rig to various stress intensities for multiple fatigue cycles. Thousands of local diffraction patterns (1 mu m(2) spot area) spanning hundreds of micrometers surrounding the crack tips, were combined to produce contour maps of phase volume and local strain. The differences in monotonic and cyclic loading conditions can be deduced from these tests and can be used to differentiate in vivo single-event versus cumulative-damage fractures. C1 [Robertson, Scott W.] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Robertson, SW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 11 TC 0 Z9 0 U1 0 U2 9 PU ASM INTERNATIONAL PI MATERIALS PARK PA 9503 KINSMAN RD, MATERIALS PARK, OH 44073 USA BN 978-0-87170-862-5 PY 2008 BP 35 EP 41 DI 10.1361/cp2006smst035 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA BQI76 UT WOS:000281128400004 ER PT B AU Robertson, SW Stankiewicz, JM Ritchie, RO AF Robertson, Scott W. Stankiewicz, Jessica M. Ritchie, Robert O. BE Berg, B Mitchell, MR Proft, J TI A Fracture-Mechanics Based Approach to Fatigue of Nitinol Tube SO SMST 2006: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON SHAPE MEMORY AND SUPERELASTIC TECHNOLOGIES LA English DT Proceedings Paper CT International Conference on Shape Memory and Superelastic Technologies CY MAY 07-11, 2006 CL Pacific Grove, CA SP Admedes Schussler GmbH, Boston Sci, Dearborn Precis Tubular Prod, Edwards Lifesciences, Ft Wayne Met Res Prod Corp, Guidant Endovasc Solut, Johnson Matthey, Kemac Technologies, Mech & Mat Consulting, Medtron Vasc, MeKo Laser Mat Proc, Memry Corp, Minitubes, Nitinol Devices & components, SAES Getters Grp, Special Met Corp, Shape Mem Alloys Div, Ulbrich Stainless Steels & Special Met ID CRACK PROPAGATION; ALLOY; WIRES AB The traditional approach to biomedical device design for resistance to fatigue failure is based on a total-life philosophy for predicting safe in vivo operating conditions. Although this approach is extremely useful for determining safe applied loads and displacements, it cannot predict the critical flaw size that may eventually lead to a cumulative damage and possible failure in an implanted device subjected to millions of pulsatile cyclic loads. Indeed, there is a dearth of relevant data in the literature on such fracture-mechanics based approaches to fatigue, and that which does exist invariably pertains to product forms that are not appropriate for stent manufacture, namely bulk Nitinol bar and sheet. The results presented herein document the fatigue and fracture response in Nitinol tubing, similar to that used for medical device manufacture, which has undergone a series of shape-setting procedures to flatten the material. The resultant A(f) temperature is similar to 25-30 degrees C, identical to self-expanding Nitinol stents. The fatigue behavior at various load ratios (R = 0.1, 0.5, and 0.7) is presented and shows higher fatigue thresholds than previous literature sources have reported for bulk Nitinol material. Our objective is to combine the well-characterized total-life predictions with fatigue/fracture data from compact-tension specimens at controlled flaw sizes in order to aid the development of stents with enhanced structural longevity. C1 [Robertson, Scott W.] Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Robertson, SW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 16 TC 0 Z9 0 U1 0 U2 2 PU ASM INTERNATIONAL PI MATERIALS PARK PA 9503 KINSMAN RD, MATERIALS PARK, OH 44073 USA BN 978-0-87170-862-5 PY 2008 BP 53 EP 60 DI 10.1361/cp2006smst053 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA BQI76 UT WOS:000281128400006 ER PT B AU Roschke, MA Parliman, BJ Cook, DP Sherrill, CD AF Roschke, Mark A. Parliman, Bart J. Cook, Danny P. Sherrill, C. David GP IEEE COMPUTER SOC TI Parallel Processing of Data, Metadata, and Aggregates Within an Archival Storage System User Interface (Toward Archiving a Million Files and a Million Megabytes per Minute) SO SNAPI 2008: FIFTH IEEE INTERNATIONAL WORKSHOP ON STORAGE NETWORK ARCHITECTURE AND PARALLEL I/OS, PROCEEDINGS SE International Workshop on Storage Network Architecture and Parallel I/Os LA English DT Proceedings Paper CT 5th IEEE International Workshop on Storage Network Architecture and Parallel I/Os CY SEP 22, 2008 CL Baltimore, MD SP IEEE, MSSTC, exegy, BECS Technol AB Archiving large datasets requires parallel processing of both data and metadata for timely execution. This paper describes the work in progress to use various processing techniques, including multi-threading of data and metadata operations, distributed processing, aggregation, and conditional processing to achieve increased archival performance for large datasets. C1 [Roschke, Mark A.; Parliman, Bart J.; Cook, Danny P.; Sherrill, C. David] Los Alamos Natl Lab, High Performance Comp Div, Los Alamos, NM 87545 USA. RP Roschke, MA (reprint author), Los Alamos Natl Lab, High Performance Comp Div, Los Alamos, NM 87545 USA. EM mar@lanl.gov; bartp@lanl.gov; dpc@lanl.gov; dsherril@lanl.gov NR 1 TC 1 Z9 1 U1 3 U2 3 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 978-0-7695-3408-4 J9 I W STOR NETW ARCH PY 2008 BP 36 EP 43 DI 10.1109/SNAPI.2008.10 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BIZ62 UT WOS:000263987000005 ER PT B AU Cui, XH Pullum, LL Treadwell, J Patton, RM Potok, TE AF Cui, Xiaohui Pullum, Laura L. Treadwell, Jim Patton, Robert M. Potok, Thomas E. BE Liu, H Salerno, JJ Young, MJ TI Particle swarm social model for group social learning in adaptive environment SO SOCIAL COMPUTING, BEHAVIORAL MODELING AND PREDICTION LA English DT Proceedings Paper CT 1st International Workshop on Social Computing, Behavioral Modeling and Prediction CY APR 01-02, 2008 CL Phoenix, AZ AB This report presents a study of integrating particle swarm algorithm, social knowledge adaptation and multi-agent approaches for modeling the social learning of self-organized groups and their collective searching behavior in an adaptive environment. The objective of this research is to apply the particle swarm metaphor as a model of social learning for a dynamic environment. The research provides a platform for understanding and insights into knowledge discovery and strategic search in human self-organized social groups, such as human communities. C1 [Cui, Xiaohui; Treadwell, Jim; Patton, Robert M.; Potok, Thomas E.] Oak Ridge Natl Lab, Computat Sci & Engn Div, Oak Ridge, TN 37831 USA. [Pullum, Laura L.] Lockheed Martin Corp, St Paul, MN 55164 USA. RP Cui, XH (reprint author), Oak Ridge Natl Lab, Computat Sci & Engn Div, Oak Ridge, TN 37831 USA. FU U.S.Department of Energy [DE-AC05-00OR22725] FX Prepared by Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6285, managed by UT-Battelle, LLC, for the U.S.Department of Energy under contract DE-AC05-00OR22725; and by Lockheed Martin, partially funded by internal Lockheed research funds. NR 16 TC 1 Z9 1 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013, UNITED STATES BN 978-0-387-77671-2 PY 2008 BP 141 EP + DI 10.1007/978-0-387-77672-9_16 PG 3 WC Computer Science, Information Systems; Computer Science, Theory & Methods; Information Science & Library Science; Social Issues SC Computer Science; Information Science & Library Science; Social Issues GA BHM05 UT WOS:000254217600016 ER PT B AU Sanfilippo, A Franklin, L Tratz, S Danielson, G Mileson, N Riensche, R McGrath, L AF Sanfilippo, Antonio Franklin, Lyndsey Tratz, Stephen Danielson, Gary Mileson, Nicholas Riensche, Roderick McGrath, Liam BE Liu, H Salerno, JJ Young, MJ TI Automating frame analysis SO SOCIAL COMPUTING, BEHAVIORAL MODELING AND PREDICTION LA English DT Proceedings Paper CT 1st International Workshop on Social Computing, Behavioral Modeling and Prediction CY APR 01-02, 2008 CL Phoenix, AZ AB Frame Analysis has come to play an increasingly stronger role in the study of social movements in Sociology and Political Science. While significant steps have been made in providing a theory of frames and framing, a systematic characterization of the frame concept is still largely lacking and there are no recognized criteria and methods that can be used to identify and marshal frame evidence reliably and in a time and cost effective manner. Consequently, current Frame Analysis work is still too reliant on manual annotation and subjective interpretation. The goal of this paper is to present an approach to the representation, acquisition and analysis of frame evidence which leverages Content Analysis, Information Extraction and Semantic Search methods to automate frame annotation and provide a systematic treatment of Frame Analysis. C1 [Sanfilippo, Antonio; Franklin, Lyndsey; Tratz, Stephen; Danielson, Gary; Mileson, Nicholas; Riensche, Roderick; McGrath, Liam] Pacific NW Natl Lab, Richland, WA 99352 USA. RI Sanfilippo, Antonio/B-6743-2016 OI Sanfilippo, Antonio/0000-0001-7097-4562 NR 20 TC 2 Z9 2 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013, UNITED STATES BN 978-0-387-77671-2 PY 2008 BP 239 EP 248 DI 10.1007/978-0-387-77672-9_26 PG 10 WC Computer Science, Information Systems; Computer Science, Theory & Methods; Information Science & Library Science; Social Issues SC Computer Science; Information Science & Library Science; Social Issues GA BHM05 UT WOS:000254217600026 ER PT J AU Nikravesh, M AF Nikravesh, Masoud TI Evolution of fuzzy logic: from intelligent systems and computation to human mind SO SOFT COMPUTING LA English DT Article; Proceedings Paper CT BISC International Special Event on Forging the Frontiers (BISCSE'05) CY NOV 03-06, 2005 CL Univ Calif Berkeley, Berkeley, CA HO Univ Calif Berkeley DE nature of mind; Zadeh; fuzzy sets; logic; vagueness AB Inspired by human's remarkable capability to perform a wide variety of physical and mental tasks without any measurements and computations and dissatisfied with classical logic as a tool for modeling human reasoning in an imprecise environment, Lotfi A. Zadeh developed the theory and foundation of fuzzy logic with his 1965 paper "Fuzzy sets" (Zadeh in Inf Control 8:378-53, 1965) and extended his work with his 2005 paper "Toward a generalized theory of uncertainty (GTU)-an outline" (Zadeh in Inf Control, 2005). Fuzzy logic has at least two main sources over the past century. The first of these sources was initiated by Peirce in the form what he called a logic of vagueness in 1900s, and the second source is Lotfi's A. Zadeh work, fuzzy sets and fuzzy Logic in the 1960s and 1970s. C1 Univ Calif Berkeley, Div Comp Sci, BISC Program, EECS Dept, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Nikravesh, M (reprint author), Univ Calif Berkeley, Div Comp Sci, BISC Program, EECS Dept, Berkeley, CA 94720 USA. EM Nikravesh@eecs.berkeley.edu NR 27 TC 4 Z9 4 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING STREET, NEW YORK, NY 10013 USA SN 1432-7643 J9 SOFT COMPUT JI Soft Comput. PD JAN PY 2008 VL 12 IS 2 BP 207 EP 214 DI 10.1007/s00500-007-0192-9 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Computer Science GA 208IF UT WOS:000249312300013 ER PT J AU Stanley, CB Strey, HH AF Stanley, Christopher B. Strey, Helmut H. TI Electrostatically driven self-assembly of hybrid elastin-DNA liquid crystals SO SOFT MATTER LA English DT Article ID EQUATION-OF-STATE; DINOFLAGELLATE CHROMOSOMES; POLYMERS; NANOSTRUCTURES; TRANSITIONS; MESOPHASES; SWITCHES; CATIONS; PHASES; FORCES AB Self-assembled, hybrid liquid crystals of elastin-like peptides complexed with DNA exhibit inverse temperature-transition behavior and demonstrate functional materials design strategies. C1 [Stanley, Christopher B.] Univ Massachusetts, Dept Polymer Sci & Engn, Amherst, MA 01003 USA. [Strey, Helmut H.] SUNY Stony Brook, Dept Biomed Engn, Stony Brook, NY 11794 USA. RP Stanley, CB (reprint author), Oak Ridge Natl Lab, Neutron Scatttering Sci Div, Oak Ridge, TN 37831 USA. EM Helmut.Strey@stonybrook.edu RI Strey, Helmut/B-5456-2009; OI Stanley, Christopher/0000-0002-4226-7710 NR 31 TC 3 Z9 3 U1 1 U2 4 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1744-683X J9 SOFT MATTER JI Soft Matter PY 2008 VL 4 IS 2 BP 241 EP 244 DI 10.1039/b711675f PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 253YN UT WOS:000252553600005 ER PT J AU Liu, G Baker, GL AF Liu, Gao Baker, Gregory L. TI Structure-directed self-assembly of alkyl-aryl-ethylene oxide amphiphiles SO SOFT MATTER LA English DT Article ID LYOTROPIC LIQUID-CRYSTAL; SOLID-STATE; MOLECULAR-CONFORMATION; DIBLOCK COPOLYMER; RAMAN-SPECTROSCOPY; BLOCK-COPOLYMERS; PHASE-BEHAVIOR; CRYSTALLIZATION; POLYETHYLENE; SURFACTANTS AB Polyethylene/poly(ethylene oxide) diblock oligomers strongly phase separate and crystallize in lamellar structures. We synthesized exact length analogues that have a 1,4-disubstituted benzene ring inserted at the junction between the alkyl and PEO chains, and determined their solid-state structures. The n-alkyl chains are 14, 16, 18 or 20 carbons in length and the poly(ethylene oxide) chains 0 to 7 repeat units and are capped with methyl groups. Powder X-ray diffraction data indicate phase separation of the alkyl and ethylene oxide chains into lamellar structures with the benzene rings aligned in a planar array at the interface between the two blocks. For some compounds, an initially formed bilayer motif is transformed to an interdigitated structure upon annealing at higher temperatures. Scanning calorimetry and vibrational spectroscopy support independent crystallization of the two blocks. On cooling from the melt state, the alkyl chains crystallize first, followed by the poly(ethylene oxide) segments. Alignment of the aromatic ring via crystallization of the two blocks suggests a general approach for aligning polar molecules in nanometre-scale materials. C1 [Baker, Gregory L.] Michigan State Univ, Dept Chem, E Lansing, MI 48824 USA. [Liu, Gao] Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Baker, GL (reprint author), Michigan State Univ, Dept Chem, E Lansing, MI 48824 USA. EM bakerg@msu.edu NR 52 TC 7 Z9 7 U1 1 U2 16 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1744-683X J9 SOFT MATTER JI Soft Matter PY 2008 VL 4 IS 5 BP 1094 EP 1101 DI 10.1039/b716041k PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 288PP UT WOS:000254998600024 ER PT J AU Szmodis, AW Blanchette, CD Levchenko, AA Navrotsky, A Longo, ML Orme, CA Parikh, AN AF Szmodis, Alan W. Blanchette, Craig D. Levchenko, Andrey A. Navrotsky, Alexandra Longo, Marjorie L. Orme, Christine A. Parikh, Atul N. TI Direct visualization of phase transition dynamics in binary supported phospholipid bilayers using imaging ellipsometry SO SOFT MATTER LA English DT Article ID FORCE MICROSCOPY; SINGLE-BILAYER; LIPID-BILAYER; MEMBRANES; MONOLAYERS; COOPERATIVITY; SPECTROSCOPY; BEHAVIOR; STATES AB Via imaging ellipsometry, we study the phase transition dynamics induced by selective gelation of one component in a binary supported phopholipid bilayer. We find the modulation of two attendant morphological features: emergence of extended defect chains due to a net change in the molecular areas and fractal-like domains suggesting weak line tension. A time-lapse analysis of the ellipsometric images reveals the cluster size of 4-20 molecules undergoing gelation indicating weak cooperativity. These results demonstrate the use of ellipsometry for in situ, label-free, non-contact, and large-area imaging of dynamics in interfacial films. C1 [Szmodis, Alan W.; Parikh, Atul N.] Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. [Szmodis, Alan W.; Longo, Marjorie L.; Parikh, Atul N.] Univ Calif Davis, Biophys Grad Grp, Davis, CA 95616 USA. [Blanchette, Craig D.] Lawrence Livermore Natl Lab, Biophys & Interfacial Sci Grp, Livermore, CA USA. [Levchenko, Andrey A.; Navrotsky, Alexandra; Longo, Marjorie L.] Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. [Orme, Christine A.] Lawrence Livermore Natl Lab, Biosci & Biotechnol Div, Livermore, CA USA. RP Parikh, AN (reprint author), Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. EM anparikh@ucdavis.edu RI Levchenko, Andrey/B-7600-2008; Orme, Christine/A-4109-2009; PARIKH, ATUL/D-2243-2014 OI PARIKH, ATUL/0000-0002-5927-4968 NR 31 TC 14 Z9 14 U1 2 U2 9 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1744-683X J9 SOFT MATTER JI Soft Matter PY 2008 VL 4 IS 6 BP 1161 EP 1164 DI 10.1039/b801390j PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 301WU UT WOS:000255927700006 ER PT J AU Lin, JP Ding, WW Hong, KL Mays, JW Xu, ZD Yuan, YZ AF Lin, Jiaping Ding, Weiwei Hong, Kunlun Mays, Jimmy W. Xu, Zhongde Yuan, Yizhong TI Micellization coupled with facilitation of J-aggregation for poly(1,3-cyclohexadiene)-based amphiphilic block copolymers SO SOFT MATTER LA English DT Article ID LIVING ANIONIC-POLYMERIZATION; CONJUGATED POLYMERS; N-BUTYLLITHIUM/N,N,N',N'-TETRAMETHYLETHYLENEDIAMINE SYSTEM; 1,3-CYCLOHEXADIENE POLYMERS; MULTIPLE MORPHOLOGIES; TRIBLOCK COPOLYMERS; MICELLES; NANOSTRUCTURES; SOLUBILIZATION; SCATTERING AB Amphiphilic PS-b-sPCHD copolymers can associate to form micelles with PS blocks as the core surrounded by sPHCD blocks in aqueous media. J-Aggregation of the chromophores in sPCHD blocks is significantly facilitated by the micellization, resulting in a remarkable change in the photophysical properties of PS-b-sPCHD. C1 [Lin, Jiaping; Ding, Weiwei; Xu, Zhongde; Yuan, Yizhong] E China Univ Sci & Technol, Minist Educ, Sch Mat Sci & Engn, Key Lab Ultrafine Mat, Shanghai 20037, Peoples R China. [Hong, Kunlun; Mays, Jimmy W.] Oak Ridge Natl Lab, Ctr Nanophase Mat Sci, Oak Ridge, TN 37831 USA. [Hong, Kunlun; Mays, Jimmy W.] Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37831 USA. [Mays, Jimmy W.] Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Lin, JP (reprint author), E China Univ Sci & Technol, Minist Educ, Sch Mat Sci & Engn, Key Lab Ultrafine Mat, Shanghai 20037, Peoples R China. EM jplinlab@online.sh.cn; hongkq@ornl.gov RI LIN, Jiaping/A-8734-2012; Hong, Kunlun/E-9787-2015 OI Hong, Kunlun/0000-0002-2852-5111 FU National Natural Science Foundation of China [50673026, 20574018]; Division of Material Sciences and Engineering, Office of Basic Energy Sciences, U. S. Department of Energy [DE-AC05-00OR22725] FX Financial support from the National Natural Science Foundation of China (Grant Nos. 50673026 and 20574018) is acknowledged. This research was also supported by the Division of Material Sciences and Engineering, Office of Basic Energy Sciences, U. S. Department of Energy, under contract # DE-AC05-00OR22725 with Oak Ridge National Laboratory managed and operated by UT-Battelle, LLC. The polymers were synthesized at the Center for Nanophase Materials Sciences of Oak Ridge National Laboratory, which is sponsored at ORNL by the Division of Scientific User Facilities, U. S. Department of Energy. We are thankful to Dr Reza Dabestani of the Chemical Science Division, ORNL, for the help with repeating the fluorescence measurements and also very grateful to Prof. Jean-Pierre Desvergne of University Bordeaux 1, France, for stimulating discussions regarding the analysis of the fluorescence results. NR 46 TC 12 Z9 12 U1 0 U2 8 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1744-683X J9 SOFT MATTER JI Soft Matter PY 2008 VL 4 IS 8 BP 1605 EP 1608 DI 10.1039/b804838j PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 364ZX UT WOS:000260376800006 ER PT J AU Gaines, MK Smith, SD Samseth, J Bockstaller, MR Thompson, RB Rasmussen, KO Spontak, RJ AF Gaines, Michelle K. Smith, Steven D. Samseth, Jon Bockstaller, Michael R. Thompson, Russell B. Rasmussen, Kim O. Spontak, Richard J. TI Nanoparticle-regulated phase behavior of ordered block copolymers SO SOFT MATTER LA English DT Article ID POLYMER NANOCOMPOSITES; COMPOSITES; SIZE; NANOTECHNOLOGY; SEGREGATION; TRANSITION; MESOPHASES; ALGORITHM AB Although block copolymer motifs have received considerable attention as supramolecular templates for inorganic nanoparticles, experimental observations of a nanostructured diblock copolymer containing inorganic nanoparticles-supported by theoretical trends predicted from a hybrid self-consistent field/density functional theory-confirm that nanoparticle size and selectivity can likewise stabilize the copolymer nanostructure by increasing its order disorder transition temperature. C1 [Rasmussen, Kim O.] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. [Gaines, Michelle K.; Spontak, Richard J.] N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. [Smith, Steven D.] Procter & Gamble Co, Miami Valley Innovat Ctr, Cincinnati, OH 45061 USA. [Samseth, Jon] SINTEF Mat & Chem, Proc Technol Dept, N-7465 Trondheim, Norway. [Samseth, Jon] Akershus Univ Coll, N-2001 Lillestrom, Norway. [Bockstaller, Michael R.] Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. [Thompson, Russell B.] Univ Waterloo, Dept Phys & Astron, Waterloo, ON N2L 3G1, Canada. [Spontak, Richard J.] N Carolina State Univ, Dept Chem & Biomol Engn, Raleigh, NC 27695 USA. RP Rasmussen, KO (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Rasmussen, Kim/B-5464-2009; Bockstaller, Michael/A-9124-2011; Thompson, Russell/J-6326-2012 OI Rasmussen, Kim/0000-0002-4029-4723; Bockstaller, Michael/0000-0001-9046-9539; Thompson, Russell/0000-0002-6571-558X FU Research Council of Norway; U. S. Department of Energy at Los Alamos National Laboratory [DE-AC52-06NA25396]; NSERC of Canada FX This work was supported by the Research Council of Norway under the NANOMAT Program. Research at LANL is performed under the auspices of the National Nuclear Security Administration of the U. S. Department of Energy at Los Alamos National Laboratory under Contract No. DE-AC52-06NA25396. R. B. T. thanks the NSERC of Canada for financial support, and M. K. G. expresses her gratitude for a GEM Fellowship and a NOBCChE Procter and Gamble Fellowship. NR 39 TC 30 Z9 30 U1 0 U2 16 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1744-683X J9 SOFT MATTER JI Soft Matter PY 2008 VL 4 IS 8 BP 1609 EP 1612 DI 10.1039/b805540h PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 364ZX UT WOS:000260376800007 ER PT J AU Schaefer, DW Zhao, J Dowty, H Alexander, M Orler, EB AF Schaefer, Dale W. Zhao, Jian Dowty, Heather Alexander, Max Orler, E. Bruce TI Carbon nanofibre reinforcement of soft materials SO SOFT MATTER LA English DT Article ID ATOMIC-FORCE MICROSCOPY; SMALL-ANGLE SCATTERING; PRECIPITATED SILICA; POLYMER COMPOSITES; DYNAMIC PROPERTIES; ELASTOMERS; NANOTUBES; NANOCOMPOSITES; DEFORMATION; DISPERSION AB In elastomeric matrices carbon nanofibres are found to be twenty times more effective than carbon black as a reinforcing filler. In hard matrices, by contrast, reinforcement is minimal. Tensile and dynamic mechanical tests were performed to elucidate the mechanism of reinforcement in order to explain the superior performance in soft matrices. Small-angle neutron scattering and ultra-small-angle X-ray scattering were used to quantify filler morphology, which turns out to be the key factor that limits reinforcement potential. The presence of fractal cluster formed by agglomeration of the nanofibres reduces the effective aspect ratio of the nanotubes. Clustering, however, introduces a new reinforcement mechanism based on elastic deformation of the fibre clusters. This mechanism is operative in soft matrices but not in hard matrices, thus explaining the enhanced performance in soft matrices. C1 [Schaefer, Dale W.; Zhao, Jian] Univ Cincinnati, Dept Chem & Mat Engn, Cincinnati, OH 45221 USA. [Zhao, Jian] Qingdao Univ Sci & Technol, Key Lab Rubber Plast, Minist Educ, Qingdao, Peoples R China. [Dowty, Heather; Alexander, Max] USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. [Orler, E. Bruce] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schaefer, DW (reprint author), Univ Cincinnati, Dept Chem & Mat Engn, Cincinnati, OH 45221 USA. EM dale.schaefer@uc.edu RI USAXS, APS/D-4198-2013 FU National Institute of Standards and Technology, U. S. Department of Commerce; U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences [W-31-109-ENG-38] FX We especially appreciate the efforts of Ryan Justice, Jan Ilavsky and Dave Anderson in collection of the scattering data and Doug Kohls in collection of the DMA data. ScopingDMA studies (not reported) were carried out by Chris Pfeifer. We thank Man-Ho Kim for his assistance in the neutron scattering work. We acknowledge the support of the National Institute of Standards and Technology, U. S. Department of Commerce, in providing the neutron research facilities used in this work. Use of the Advanced Photon Source was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. W-31-109-ENG-38. The facilities of the Manuel Lujan Jr. Neutron Scattering Centre are gratefully appreciated. The work at the Lujan Centre was supported in part by the Office of Basic Energy Science, U. S. Department of Energy. NR 42 TC 11 Z9 11 U1 0 U2 6 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1744-683X J9 SOFT MATTER JI Soft Matter PY 2008 VL 4 IS 10 BP 2071 EP 2079 DI 10.1039/b805314f PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 365AA UT WOS:000260377100015 ER PT J AU Yaklin, MA Duxbury, PM Mackay, ME AF Yaklin, Melissa A. Duxbury, Phillip M. Mackay, Michael E. TI Control of nanoparticle dispersion in thin polymer films SO SOFT MATTER LA English DT Article ID SOLAR-CELLS; MOLECULAR ARCHITECTURE; POLYSTYRENE FILMS; COMPOSITES; MIXTURES; NANOCOMPOSITES; SUPPRESSION; SOLUBILITY; INTERFACES; VISCOSITY AB We have found larger (>5 nm) nanoparticles are uniformly distributed in a polymer film immediately after spin-coating. However, using the same thin film fabrication process leads to C(60) nanoparticle segregation to the substrate, resulting in a kinetically trapped state that resists dispersion. The additional processing steps introduced here are found to yield uniform dispersion of these small nanoparticles in polymer films. Moreover, we show that although very small nanoparticles, such as C(60) fullerenes, can be homogeneously distributed in the film, larger organic nanoparticles subsequently phase separate to the solid substrate. Both processes, dispersion and segregation in thin films, are primarily driven through entropic terms dictated by the relative size of the nanoparticle and polymer statistical segment. This is in agreement with a simple theory and supported by density functional theory calculations that predict uniform dispersion in thin films when the nanoparticle diameter is less than similar to 1.5 times the size of a polymer statistical segment. This is despite the fact that both the larger and C(60) nanoparticles are miscible in the bulk, demonstrating the thermodynamic influence of a hard substrate. Morphologies are characterized via neutron reflectivity measurements throughout the study to accurately characterize nanoparticle dispersion. C1 [Yaklin, Melissa A.; Mackay, Michael E.] Michigan State Univ, Dept Chem Engn & Mat Sci, E Lansing, MI 48824 USA. [Yaklin, Melissa A.] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Duxbury, Phillip M.; Mackay, Michael E.] Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. RP Mackay, ME (reprint author), Michigan State Univ, Dept Chem Engn & Mat Sci, E Lansing, MI 48824 USA. FU U.S. Department of Energy [DEFG02-05ER46211] FX We appreciate funding from the U.S. Department of Energy that enabled this research (contract no. DEFG02-05ER46211). Use of the Intense Pulsed Neutron Source at Argonne National Laboratory and the SPEAR reflectometer at the Los Alamos Neutron Scattering Center at Los Alamos National Laboratory is also greatly appreciated. NR 52 TC 21 Z9 21 U1 0 U2 36 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1744-683X J9 SOFT MATTER JI Soft Matter PY 2008 VL 4 IS 12 BP 2441 EP 2447 DI 10.1039/b807565d PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Physics; Polymer Science GA 384EF UT WOS:000261726400019 ER PT B AU Panas, T AF Panas, Thomas BE Spencer, SN TI Signature Visualization of Software Binaries SO SOFTVIS 2008: PROCEEDINGS OF THE 4TH ACM SYMPOSIUM ON SOFTWARE VISUALIZATION LA English DT Proceedings Paper CT 4th ACM Symposium on Software Visualization CY SEP 16-17, 2008 CL Herrsching am Ammersee, GERMANY SP ACM SIGGRAPH, ACM SIGSOFT, ACM SIGPLAN, ACM SIGCHI DE binary analysis; malware visualization AB In this paper we present work on the visualization of software binaries. In particular, we utilize ROSE, an open source compiler infrastructure, to pre-process software binaries, and we apply a landscape metaphor to visualize the signature of each binary (malware). We define the signature of a binary as a metric-based layout of the functions contained in the binary. In our initial experiment, we visualize the signatures of a series of computer worms that all originate from the same line. These visualizations are useful for a number of reasons. First, the images reveal how the archetype has evolved over a series of versions of one worm. Second, one can see the distinct changes between versions. This allows the viewer to form conclusions about the development cycle of a particular worm. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA USA. RP Panas, T (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA USA. EM panas@llnl.gov NR 8 TC 0 Z9 0 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036-9998 USA BN 978-1-60558-112-5 PY 2008 BP 185 EP 188 PG 4 WC Computer Science, Software Engineering SC Computer Science GA BJG96 UT WOS:000265740700022 ER PT J AU Zhuang, J McCarthy, JF Perfect, E Mayer, LM Jastrow, JD AF Zhuang, J. McCarthy, J. F. Perfect, E. Mayer, L. M. Jastrow, J. D. TI Soil water hysteresis in water-stable microaggregates as affected by organic matter SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID FRACTAL ANALYSIS; SEWAGE-SLUDGE; CARBON; AGGREGATE; MECHANISMS; DYNAMICS; TILLAGE; SEQUESTRATION; WETTABILITY; PARTICULATE AB Interaction of water and organic matter (OM) in pores affects the capacity for long-term C sequestration and water retention in soils. This study investigated the effects of the amount and distribution of OM in microstructures on water retention in soil microaggregates. The focus of the study was on the hysteretic soil water characteristic (i.e., the difference between the main drying and wetting curves), which has been largely ignored in previous studies on water-OM relations. The main drying and wetting branches of the water retention curve were measured using a water activity meter on water-stable microaggregates (53-250 mu m), which were collected from surface soils (0-15 cm) subject to different management practices: tallgrass prairie restoration on a Mollisol, and tillage with and without N fertilization on an Alfisol. The results show that the presence of OM in <5-mu m-diameter pores increases water retention in microaggregates, while management practices that either increased or decreased the abundance of OM-filled pore volume in the microaggregates promoted hysteresis of water retention characteristics due to changes in soil pore structure. Comparison of the drying and wetting curves between intact and combusted (OM removed) microaggregates indicated a strong retention of water by pore-filling OM. This retention suggests that the high water saturation in microaggregates from soils under management practices that increased OM-filled porosity, which also offered physical protection of the OM, may be a positive feedback mechanism that retards OM decomposition in micropores. The water retention data measured on intact and combusted microaggregates were consistent with results from ultra-small-angle x-ray scattering, and indicated that management practices have a great potential for facilitating the synergistic retention of water and organic C in soils. C1 [Zhuang, J.; McCarthy, J. F.; Perfect, E.] Univ Tennessee, Dept Earth & Planetary Sci, Ctr Environm Biotechnol, Inst Secure & Sustainable Environm, Knoxville, TN 37996 USA. [Mayer, L. M.] Univ Maine, Darling Marine Ctr, Walpole, ME 04573 USA. [Jastrow, J. D.] Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Zhuang, J (reprint author), Univ Tennessee, Dept Earth & Planetary Sci, Ctr Environm Biotechnol, Inst Secure & Sustainable Environm, Knoxville, TN 37996 USA. EM jzhuang@utk.edu RI Mayer, Lawrence/A-1337-2009; Ilavsky, Jan/D-4521-2013; USAXS, APS/D-4198-2013 OI Ilavsky, Jan/0000-0003-1982-8900; NR 37 TC 29 Z9 30 U1 1 U2 18 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD JAN-FEB PY 2008 VL 72 IS 1 BP 212 EP 220 DI 10.2136/sssaj2007.0001 PG 9 WC Soil Science SC Agriculture GA 255TV UT WOS:000252681300026 ER EF