FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Lin, CC Zangvil, A Ruh, R AF Lin, CC Zangvil, A Ruh, R TI Modes of oxidation in SiC-reinforced mullite/ZrO2 composites: Oxidation vs depth behavior SO ACTA MATERIALIA LA English DT Article ID PRESSED SILICON-CARBIDE; STABILIZED ZIRCONIA; KINETICS; MICROSTRUCTURE; CRYSTALS; OXYGEN AB Two basic oxidation modes of composites with oxidizing particles in a non-oxidizing matrix have been observed. Mode I is defined as the complete oxidation of all the particles within an outer layer of the composite, while mode II exhibits partial oxidation of the particles, deep into the composite. Using microscopic observations to plot the silica layer thickness on particles (whiskers) vs the depth of the particles (whiskers) below the composite surface is proposed as a powerful means of categorizing and quantifying actual oxidation modes. Thus, mullite/SiC-whisker composites were found to have mode I oxidation behavior, while certain (mullite + ZrO2)/SiC-whisker composites were found to exhibit mode II behavior, followed by a mixed mode after severe exposures. It is proposed that mode II behavior appears when oxygen diffusivity in the matrix is much higher than that in the product oxide layer. (C) 1999 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Natl Tsing Hua Univ, Dept Mat Sci & Engn, Hsinchu 300, Taiwan. Univ Illinois, Frederick Seitz Mat Res Lab, Urbana, IL 61801 USA. Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. USAF, Wright Aeronaut Labs, Wright Patterson AFB, OH 45433 USA. RP Lin, CC (reprint author), Natl Tsing Hua Univ, Dept Mat Sci & Engn, Hsinchu 300, Taiwan. NR 39 TC 8 Z9 8 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD APR 23 PY 1999 VL 47 IS 6 BP 1977 EP 1986 DI 10.1016/S1359-6454(99)00027-0 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 195TU UT WOS:000080268900026 ER PT J AU DeLo, DP Dutton, RE Semiatin, SL AF DeLo, DP Dutton, RE Semiatin, SL TI A comparison of discrete element model predictions to observations of metal powder consolidation SO SCRIPTA MATERIALIA LA English DT Article ID ISOSTATIC PRESSING HIP; PLASTICITY THEORY; DENSIFICATION; DEFORMATION; COMPACTS; BEHAVIOR; PACKINGS; RATES C1 MLLM, AFRL, Wright Patterson AFB, OH 45433 USA. Syst Fed Corp, Dayton, OH USA. RP DeLo, DP (reprint author), MLLM, AFRL, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 24 TC 5 Z9 5 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD APR 23 PY 1999 VL 40 IS 10 BP 1103 EP 1109 DI 10.1016/S1359-6462(99)00060-3 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 208GT UT WOS:000080983200003 ER PT J AU Hader, J Bossert, D Stohs, J Chow, WW Koch, SW Moloney, JV AF Hader, J Bossert, D Stohs, J Chow, WW Koch, SW Moloney, JV TI Clamping of the linewidth enhancement factor in narrow quantum-well semiconductor lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID GAIN SPECTRA; ALPHA AB The linewidth enhancement factor in single quantum-well graded index separate confinement heterostructure semiconductor lasers is investigated theoretically and experimentally. For thin wells, a small linewidth enhancement factor is obtained which clamps with increasing carrier density, in contrast to the monotonous increase observed for thicker wells. Microscopic many-body calculations reproduce the experimental observations attributing the clamping to excitation dependent gain shifts and the influence of the population of off-resonant states on the refractive index. (C) 1999 American Institute of Physics. [S0003-6951(99)04016-4]. C1 Univ Arizona, Arizona Ctr Math Sci, Tucson, AZ 85721 USA. USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Marburg, Dept Phys, D-35032 Marburg, Germany. Univ Marburg, Ctr Mat Sci, D-35032 Marburg, Germany. RP Hader, J (reprint author), Univ Arizona, Arizona Ctr Math Sci, Tucson, AZ 85721 USA. NR 11 TC 39 Z9 39 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 19 PY 1999 VL 74 IS 16 BP 2277 EP 2279 DI 10.1063/1.123823 PG 3 WC Physics, Applied SC Physics GA 186NU UT WOS:000079736500009 ER PT J AU Rujirawat, S Xin, Y Browning, ND Sivananthan, S Smith, DJ Tsen, SCY Chen, YP Nathan, V AF Rujirawat, S Xin, Y Browning, ND Sivananthan, S Smith, DJ Tsen, SCY Chen, YP Nathan, V TI CdTe(111)B grown on Si(111) by molecular beam epitaxy SO APPLIED PHYSICS LETTERS LA English DT Article ID MISORIENTED SI(001); CDTE; SI; HGCDTE; ORIENTATION; HG1-XCDXTE AB We demonstrate the growth of large-area, domain-free CdTe(111) single crystals on As-passivated Si(111) substrates by molecular beam epitaxy using ZnTe buffer layers. The crystal quality of the CdTe(111)B/ZnTe(111)B/Si(111) films was examined by x-ray diffraction (56 arcs), etch-pit-density (2 x 10(5) cm(-2)) analysis, and transmission electron microscopy, and was found to be comparable to or better than the best CdTe(111)B films grown directly on vicinal Si(001). Surface reconstructions were observed by reflection high-energy electron diffraction at different stages. Diffraction intensity oscillations demonstrated the layer-by-layer growth mode of the CdTe surface. An interface model for these films is proposed. (C) 1999 American Institute of Physics. [S0003-6951(99)02916-2]. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. EPIR Ltd, Lisle, IL 60532 USA. USAF, Res Lab VSSS, Kirtland AFB, NM 87117 USA. RP Rujirawat, S (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. OI Browning, Nigel/0000-0003-0491-251X NR 23 TC 23 Z9 23 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 19 PY 1999 VL 74 IS 16 BP 2346 EP 2348 DI 10.1063/1.123846 PG 3 WC Physics, Applied SC Physics GA 186NU UT WOS:000079736500032 ER PT J AU Chun, FK Knipp, DJ McHarg, MG Lu, G Emery, BA Vennerstrom, S Troshichev, OA AF Chun, FK Knipp, DJ McHarg, MG Lu, G Emery, BA Vennerstrom, S Troshichev, OA TI Polar cap index as a proxy for hemispheric Joule heating SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HIGH-LATITUDE THERMOSPHERE; AE; PC; IONOSPHERE; AL; AU AB The polar cap (PC) index measures the level of geomagnetic activity in the polar cap based on magnetic perturbations from overhead ionospheric currents and distant field-aligned currents on the poleward edge of the nightside auroral oval. Because PC essentially measures the main sources of energy input into the polar cap, we propose to use PC as a proxy for the hemispheric Joule heat production rate (JH). In this study, JH is estimated from the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure. We fit hourly PC values to hourly averages of JH. Using a data base approximately three times larger than studies, we find a quadratic relationship between JH and PC, differentiated by season. A comparison during the November 1993 storm interval with earlier reported methods using the AE index and the cross polar cap potential, shows that the PC-based Joule heating estimate is as equally accurate. Thus the single station PC index appears to provide a quick estimate of, and is an appropriate proxy for, the hemispheric Joule heating rate. C1 USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. Danish Space Res Inst, DK-2100 Copenhagen, Denmark. Arctic & Antarctic Res Inst, St Petersburg 199397, Russia. RP Chun, FK (reprint author), USAF Acad, Dept Phys, 2354 Fairchild Dr,Suite 2A31, Colorado Springs, CO 80840 USA. RI Lu, Gang/A-6669-2011 NR 24 TC 52 Z9 52 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 15 PY 1999 VL 26 IS 8 BP 1101 EP 1104 DI 10.1029/1999GL900196 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 187NW UT WOS:000079793700025 ER PT J AU Fingers, RT Coate, JE Dowling, NE AF Fingers, RT Coate, JE Dowling, NE TI Creep deformation of a soft magnetic iron-cobalt alloy SO JOURNAL OF APPLIED PHYSICS LA English DT Article; Proceedings Paper CT 43rd Annual Conference on Magnetism and Magnetic Materials CY NOV 09-12, 1998 CL MIAMI, FLORIDA SP Amer Inst Phys, IEEE Magnet Soc, Minerals Met Mat Soc, Amer Soc Testing & Mat, Amer Ceramic Soc, Amer Phys Soc, EMTEC Magnet GmbH, Fuji Photo Film Co Ltd, IBM, Imation, Sony corp, TDK Corp, Toda Kogyo Corp, ADE Technol Inc, digital Measurement Syst Div, Komag, MMC Technol Inc AB The U.S. Air Force is in the process of developing magnetic bearings, as well as an aircraft integrated power unit and an internal starter/generator for main propulsion engines. These developments are the driving force for the new emphasis on the development of high saturation, low loss magnets capable of maintaining structural integrity in high stress and high temperature environments. It is this combination of desired material characteristics that is the motivation of this effort to measure, model, and predict the creep behavior of such advanced magnetic materials. Hiperco(R) Alloy 50HS, manufactured by Carpenter Technology Corporation, is one of the leading candidates for these applications. Material specimens were subjected to a battery of mechanical tests in order to study and characterize their behaviors. Tensile tests provided stress versus strain behaviors that clearly indicated: a yield point, a heterogeneous deformation described as Luders elongation, the Portevin-LeChatelier effect at elevated temperatures, and most often a section of homogeneous deformation that concluded with necking and fracture. Creep testing indicated three distinct types of behavior. Two types resembled a traditional response with primary, secondary, and tertiary stages; while the third type can be characterized by an abrupt increase in strain rate that acts as a transition from one steady-state behavior to another. The relationships between the tensile and creep responses are discussed. Analyses of the mechanical behavior include double linear regression of empirically modeled data, and constant strain rate testing to bridge the tensile and creep test parameters. (C) 1999 American Institute of Physics. [S0021-8979(99)77908-9]. C1 USAF, Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. RP Fingers, RT (reprint author), USAF, Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. NR 5 TC 13 Z9 14 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1999 VL 85 IS 8 BP 6037 EP 6039 DI 10.1063/1.369074 PN 2B PG 3 WC Physics, Applied SC Physics GA 188NF UT WOS:000079853500247 ER PT J AU Christ, JA Goltz, MN Huang, JQ AF Christ, JA Goltz, MN Huang, JQ TI Development and application of an analytical model to aid design and implementation of in situ remediation technologies SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article DE groundwater movement; circulation; wells; remediation; bioremediation; mathematical models; reinjection wells; modeling ID LABORATORY-SCALE ANALYSIS; COMETABOLIC DEGRADATION; AQUIFER REMEDIATION; GROUNDWATER; SYSTEM AB Innovative in situ remediation technologies using injection/extraction well pairs which recirculate partially treated groundwater as a method of increasing overall treatment efficiency have recently been demonstrated, An important parameter in determining overall treatment efficiency is the fraction of flow that recycles between injection and extraction points. Numerical and semi-analytical methods are currently available to determine this parameter and an analytical solution has been presented for a single injection/extraction well pair. In this work, the analytical solution for fraction of recycled flow for a single injection/extraction well pair is extended to multiple co-linear well pairs. In addition, a semi-analytical method is presented which permits direct calculation of fraction recycle for a system of arbitrarily placed injection/extraction wells pumping at different rates. The solution is used to investigate the behavior of multiple well pairs, looking at how well placement and pumping rates impact capture zone width and fraction recirculation (and, therefore, overall treatment efficiency). Results of the two-well solution are compared with data obtained at a recent field-scale demonstration of in situ aerobic cometabolic bioremediation, where a pair of dual-screened injection/extraction wells was evaluated. A numerical model is then used to evaluate the impact of hydraulic conductivity anisotropy on the overall treatment efficiency of the dual-screened injection/extraction well pair. The method presented here provides a fast and accurate technique for determining the efficacy of injection/extraction systems, and represents a tool that can be useful when designing such in situ treatment systems. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 USAF, Inst Technol, Dept Engn & Environm Management, Wright Patterson AFB, OH 45433 USA. CEV, CES 5, Minot AFB, ND 58705 USA. RP Goltz, MN (reprint author), USAF, Inst Technol, Dept Engn & Environm Management, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. RI Goltz, Mark/A-7394-2009; OI Goltz, Mark/0000-0003-3601-6453 NR 29 TC 32 Z9 32 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD APR 15 PY 1999 VL 37 IS 3-4 BP 295 EP 317 DI 10.1016/S0169-7722(99)00002-9 PG 23 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 193EQ UT WOS:000080123300004 ER PT J AU Thomas, JM Viggiano, AA AF Thomas, JM Viggiano, AA TI Kinetics for the reactions of H3O+(H2O)(n) with CH3SOCH3 SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID RATE CONSTANTS; DIMETHYL-SULFOXIDE; TEMPERATURE; IONS; GAS AB We have measured the rate constants and product branching fractions for the proton hydrate clusters H3O+(H2O)(n) (n = 0-4), reacting with dimethyl sulfoxide. The reactions were studied over the temperature range 198-298 K. Larger clusters were only studied at low temperatures since they are unstable at higher temperatures. All reactions were fast, approaching the collisional limit. The small clusters are slightly slower than the collisional limit, especially at 298 K. The product distributions were measured only at 198 K. Ail reactions proceeded by formation of H+(CH3SOCH3)(H2O)(n). The major product was often the channel producing two neutral H2O molecules. The product distributions for the larger clusters were probably effected by thermal decomposition as evidenced by production of endothermic products. C1 USAF, Res Lab, Space Vehicles Directorate VSBP, Hanscom AFB, MA 01731 USA. RP Viggiano, AA (reprint author), USAF, Res Lab, Space Vehicles Directorate VSBP, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 13 TC 5 Z9 5 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD APR 15 PY 1999 VL 103 IS 15 BP 2720 EP 2722 DI 10.1021/jp9844011 PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 189YH UT WOS:000079933500033 ER PT J AU Jiang, H Su, W Brant, M De Rosa, ME Bunning, TJ AF Jiang, H Su, W Brant, M De Rosa, ME Bunning, TJ TI Chitosan-based hydrogels: A new polymer-based system with excellent laser-damage threshold properties SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE chitosan; laser damage threshold; water association; hydrogel ID DIELECTRIC-RELAXATION SPECTROSCOPY; WATER; GEL AB Two types of chitosan hydrogel systems have been prepared that have a laser damage threshold (LDT) up to 35 times higher than commercial PMMA bulk materials. For these samples, the LDT increases with increasing water content. The mechanism of laser damage and the contribution of water to their high laser damage resistance have been examined. DSC measurements indicate water within the hydrogels exist in various states, each with different laser damage resistance properties. These various states play a key role in determining the LDT by controlling the dissipation of laser energy and providing a mechanism for self-healing. This preliminary research shows that polymer hydrogels have potential for high power laser applications because they combine good mechanical integrity due to the polymer frame and good energy dissipation and healing characteristics due to the molecular mobility of water. These two traits allow for bulk shape-retaining films with high laser damage thresholds and potential reversibility in damage processes. (C) 1999 John Wiley & Sons, Inc. C1 USAF, Res Lab, MLPJ, Wright Patterson AFB, OH 45433 USA. Anteon Inc, Dayton, OH 45431 USA. Tech Management Concepts Inc, Beavercreek, OH 45432 USA. Sci Applicat Int Corp, Dayton, OH 45431 USA. RP Bunning, TJ (reprint author), USAF, Res Lab, MLPJ, Wright Patterson AFB, OH 45433 USA. NR 36 TC 5 Z9 5 U1 5 U2 28 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD APR 15 PY 1999 VL 37 IS 8 BP 769 EP 778 DI 10.1002/(SICI)1099-0488(19990415)37:8<769::AID-POLB3>3.0.CO;2-H PG 10 WC Polymer Science SC Polymer Science GA 179QL UT WOS:000079340100003 ER PT J AU Carlson, JL AF Carlson, JL TI The best in tent camping: Colorado; A guide for campers who hate RVs, concrete slabs, and loud portable stereos. SO LIBRARY JOURNAL LA English DT Book Review C1 Vandenberg AFB Lib, Vandenberg AFB, CA USA. RP Carlson, JL (reprint author), Vandenberg AFB Lib, Vandenberg AFB, CA USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD APR 15 PY 1999 VL 124 IS 7 BP 133 EP 133 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 185WM UT WOS:000079694000173 ER PT J AU Jiao, CQ Garscadden, A DeJoseph, C Haaland, PD AF Jiao, CQ Garscadden, A DeJoseph, C Haaland, PD TI Ionization of tetraethylgermanium, GeEt4 SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID RESONANCE MASS-SPECTROMETRY; RF GLOW-DISCHARGE; C ALLOY-FILMS; GE/C FILMS; PLASMA; DEPOSITION; EXCITATION; SILICON; MODEL AB The ion chemistry in tetraethylgermanium (GeEt4) has been examined by Fourier-transform mass spectrometry under single-collision conditions in the 10(-7) torr pressure range. The cross sections for electron impact ionization of GeEt4 are measured from threshold to 70 eV. The molecular ion and 15 fragment ions from the electron-molecule collision are observed with a total cross section of 3.5 +/- 0.4 x 10(-15) cm(2) at 70 eV. All fragment ions, except GeC6H15+, are found to react readily with GeEt4 to yield GeC6H15+ with rate coefficients in the range of 2-5 x 10(-10) cm(3) s(-1). Small yields of digermanium cluster ions are observed at higher reactant pressures. C1 Mobium Enterprises Inc, Dayton, OH 45431 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Jiao, CQ (reprint author), Mobium Enterprises Inc, 5100 Springfield Pike, Dayton, OH 45431 USA. NR 25 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD APR 14 PY 1999 VL 32 IS 7 BP 1639 EP 1646 DI 10.1088/0953-4075/32/7/007 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 189PN UT WOS:000079913900007 ER PT J AU Christe, KO Wilson, WW Dixon, DA Boatz, JA AF Christe, KO Wilson, WW Dixon, DA Boatz, JA TI Hetpacoordination. Synthesis and characterization of the IOF52- dianion, an XOF5E species SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID VIBRATIONAL-SPECTRA; 1ST EXAMPLE; ANION; XEOF5 AB The new IOF52- dianion was prepared in the form of its cesium salt by heating stoichiometric amounts of CsF, I2O5, and IFS to 162 degrees C for 14 days. The white stable solid was characterized by vibrational spectroscopy. A normal coordinate analysis was carried out with the help of ab initio calculations at the HF/ECP/DZP level of theory and resulted in an excellent agreement between observed and calculated frequencies. The structure of IOF52- iS that of a pentagonal bipyramid with five equatorial fluorine ligands, and an oxygen atom and one sterically active free valence electron pair occupying the two axial positions. The structure is very similar to that previously established by vibrational spectroscopy and X-ray diffraction for isoelectronic XeOF5- and represents only the second example of a heptacoordinated XOF5E (E = free valence electron pair) main group species. The possible existence of the IOF63- trianion is briefly discussed. C1 USAF, Res Lab, Edwards AFB, CA 93524 USA. Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Christe, KO (reprint author), USAF, Res Lab, Edwards AFB, CA 93524 USA. RI Christe, Karl/O-4885-2014 OI Christe, Karl/0000-0003-0661-5519 NR 32 TC 11 Z9 11 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD APR 14 PY 1999 VL 121 IS 14 BP 3382 EP 3385 DI 10.1021/ja984248o PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 189BT UT WOS:000079884800018 ER PT J AU Lo, I Hsieh, KY Hwang, SL Tu, LW Mitchel, WC Saxler, AW AF Lo, I Hsieh, KY Hwang, SL Tu, LW Mitchel, WC Saxler, AW TI Effect of threading dislocations on electron transport in In0.24Ga0.76N/GaN multiple quantum wells SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; LIGHT-EMITTING-DIODES; GAN FILMS; PHASE EPITAXY; LUMINESCENCE; SCATTERING; DEFECTS; LAYERS; DONOR AB The effect of threading dislocations on electron transport in In0.24Ga0.76N/GaN multiple quantum wells has been studied by using transmission electron microscopy (TEM) and van der Pauw Hall effect measurements. From the cross-sectional TEM imaging, we observed the threading dislocations which "screw'' through the multiple In0.24Ga0.76N/GaN quantum well. From the Hall effect measurement, we found that the Hall mobility decreases as the temperature decreases (mu similar to T-3/2) due to the threading dislocation scattering, and the Hall carrier concentration shows a transition from conduction-band transport to localized-state-hopping transport. The thermal activation energy of the residual donor level (probably Si! is about 20.2 meV. (C) 1999 American Institute of Physics. [S0003-6951(99)02415-8]. C1 Natl Sun Yat Sen Univ, Dept Phys, Kaohsiung 80424, Taiwan. Natl Sun Yat Sen Univ, Inst Mat Sci, Kaohsiung 80424, Taiwan. USAF, Mat Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Lo, I (reprint author), Natl Sun Yat Sen Univ, Dept Phys, Kaohsiung 80424, Taiwan. NR 25 TC 18 Z9 18 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 12 PY 1999 VL 74 IS 15 BP 2167 EP 2169 DI 10.1063/1.123789 PG 3 WC Physics, Applied SC Physics GA 183YT UT WOS:000079583000022 ER PT J AU Saxler, A Mitchel, WC Kung, P Razeghi, M AF Saxler, A Mitchel, WC Kung, P Razeghi, M TI Aluminum gallium nitride short-period superlattices doped with magnesium SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; STRUCTURE LASER-DIODES; EFFECTIVE-MASS; GAN; SAPPHIRE; GROWTH; TEMPERATURE; ALXGA1-XN; ALGAN AB Short-period superlattices consisting of alternating layers of GaN:Mg and AlGaN:Mg were grown by low-pressure organometallic vapor phase epitaxy. The electrical properties of these superlattices were measured as a function of temperature and compared to conventional AlGaN:Mg layers. It is shown that the optical absorption edge can be shifted to shorter wavelengths while lowering the acceptor ionization energy by using short-period superlattice structures instead of bulk-like AlGaN:Mg. (C) 1999 American Institute of Physics. [S0003-6951(99)03714-6]. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL MLPO, Wright Patterson AFB, OH 45433 USA. Northwestern Univ, Dept Elect & Comp Engn, Ctr Quantum Devices, Evanston, IL 60208 USA. RP Saxler, A (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL MLPO, Wright Patterson AFB, OH 45433 USA. RI Razeghi, Manijeh/B-7265-2009 NR 21 TC 43 Z9 46 U1 1 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 5 PY 1999 VL 74 IS 14 BP 2023 EP 2025 DI 10.1063/1.123744 PG 3 WC Physics, Applied SC Physics GA 182DM UT WOS:000079483300031 ER PT J AU Medeiros, SC AF Medeiros, SC TI Failure analysis of an aluminum casting SO ADVANCED MATERIALS & PROCESSES LA English DT Article C1 Mat Directorate, Wright Patterson AFB, OH USA. RP Medeiros, SC (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 0026-0665 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD APR PY 1999 VL 155 IS 4 BP 42 EP 42 PG 1 WC Materials Science, Multidisciplinary SC Materials Science GA 184DZ UT WOS:000079596200007 ER PT J AU Morris, MF Davis, RD Richardson, BW AF Morris, MF Davis, RD Richardson, BW TI Clinical efficacy of two dentin desensitizing agents SO AMERICAN JOURNAL OF DENTISTRY LA English DT Article ID HYPERSENSITIVE DENTIN; TUBULE OCCLUSION; CERVICAL DENTIN; PAIN; SENSITIVITY; DENTIFRICE; DURATION AB Purpose: To compare the clinical effect over 3 months of two commercially available desensitizing agents on the level of discomfort of patients with complaints of dentin sensitivity. Materials and Methods: An oxalate-containing pre-polymerized resin suspension (Pain-Free), a 0.7% fluoride solution (DentinBloc), and a distilled water placebo were compared in a clinical setting. Ten volunteer patients exhibiting three or more teeth that were sensitive to touch and to a stream of forced air were enrolled in the study (52 teeth total). Each patient's level of sensitivity to tactile stimuli and to a forced air stream was recorded using a visual analog scale (VAS). The tactile stimulus was a metal probe rubbed across the exposed dentin with a constant pressure of 40 grams. A 1-second blast of air from a dental unit air syringe was used to generate the air stream. The desensitizing agents were applied according to manufacturers' guidelines. Sensitivity measurements were recorded at baseline, immediately after treatment, at 1 week, 1 month, and at 3 months. VAS pain scores were analyzed using a repeated measures ANOVA (alpha=0.05). Results: The pre-polymerized resin suspension (Pain-Free), the fluoride-containing solution (DentinBloc), and the placebo all decreased dentin sensitivity. No significant difference was found among the desensitizing agents at any time period (P> 0.05). C1 USAF, DC, Dept Periodont, Keesler AFB, MS USA. RP Davis, RD (reprint author), 81st Dent Squadron SGD, 606 Fisher St, Keesler AFB, MS 39534 USA. NR 25 TC 37 Z9 39 U1 0 U2 0 PU MOSHER & LINDER, INC PI SAN ANTONIO PA 9859 IH-10 WEST, SUITE 107/489, SAN ANTONIO, TX 78230-2236 USA SN 0894-8275 J9 AM J DENT JI Am. J. Dent. PD APR PY 1999 VL 12 IS 2 BP 72 EP 76 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 193YR UT WOS:000080165800005 PM 10477986 ER PT J AU Ketchum, NS Michalek, JE Burton, JE AF Ketchum, NS Michalek, JE Burton, JE TI Serum dioxin and cancer in veterans of operation ranch hand SO AMERICAN JOURNAL OF EPIDEMIOLOGY LA English DT Article DE dioxins; environmental exposure; herbicides; military medicine; military personnel; neoplasms; veterans ID ARYL-HYDROCARBON HYDROXYLASE; SOFT-TISSUE SARCOMA; NON-HODGKINS-LYMPHOMA; UNITED-STATES-ARMY; AH-RECEPTOR; VIETNAM VETERANS; CELL-LINE; PHENOXY HERBICIDES; TCDD EXPOSURE; FOLLOW-UP AB We studied cancer prevalence and exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) in veterans of Operation Ranch Hand, the Air Force unit responsible for the aerial spraying of herbicides in Vietnam from 1962 to 1971. A comparison group of Air Force veterans who served in Southeast Asia during the same period and who were not involved with spraying herbicides was included. Comparison veterans were matched to Ranch Hand veterans on age, race, and military occupation. We measured dioxin in 1987 or 1992, extrapolated the result to the time of service in Southeast Asia, and assigned each Ranch Hand veteran to Background, Low, or High exposure categories. This study had low power to detect an effect for specific or rare cancers. The risk of cancer at sites other than the skin within 20 years of service was increased in the Low (odds ratio (OR) = 3.4, 95% confidence interval (CI) 1.5-8.0) and High (OR = 2.7, 95% CI 0.9-8.0) categories, but the pattern was inconsistent with another study, suggesting that the excess risk may not have been caused by dioxin exposure. Overall, we found no consistent evidence of a dose-response gradient and no significant increase in cancer risk in the High dioxin exposure category. the subgroup of greatest a priori interest. C1 USAF, Res Lab, HEDB, Brooks AFB, TX 78235 USA. RP Michalek, JE (reprint author), USAF, Res Lab, HEDB, 2606 Doolittle Rd,Bldg 807, Brooks AFB, TX 78235 USA. NR 64 TC 31 Z9 31 U1 0 U2 1 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 USA SN 0002-9262 J9 AM J EPIDEMIOL JI Am. J. Epidemiol. PD APR 1 PY 1999 VL 149 IS 7 BP 630 EP 639 PG 10 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 181QQ UT WOS:000079453500007 PM 10192310 ER PT J AU Curcio, LD Rupp, E Williams, WL Chu, DZJ Clarke, K Odom-Maryon, T Ellenhorn, JDI Somlo, G Wagman, LD AF Curcio, LD Rupp, E Williams, WL Chu, DZJ Clarke, K Odom-Maryon, T Ellenhorn, JDI Somlo, G Wagman, LD TI Beyond palliative mastectomy in inflammatory breast cancer - A reassessment of margin status SO ANNALS OF SURGICAL ONCOLOGY LA English DT Article; Proceedings Paper CT 50th Annual Cancer Symposium of the Society-of-Surgical-Oncology CY MAR 17-23, 1997 CL CHICAGO, ILLINOIS SP Soc Surg Oncol DE inflammatory breast cancer; therapy; margin status ID CARCINOMA; RADIOTHERAPY; CHEMOTHERAPY; MANAGEMENT; RECEPTORS; ESTROGEN; TUMORS AB Background: Inflammatory breast cancer is a locally advanced tumor with an aggressive local and systemic course. Treatment of this disease has been evolving over the last several decades. The aim of this study was to assess whether current therapies, both surgical and chemotherapeutic, are providing better local control (LC) and overall survival (OS). We also attempted to identify clinical and pathologic factors that may be associated with improved OS, disease-free survival (DFS), and LC. Methods: A 25-year retrospective review performed at the City of Hope National Medical Center identified 90 patients with the diagnosis of inflammatory breast cancer. Results: Of the 90 patients identified with inflammatory breast cancer, 33 received neoadjuvant therapy (NEO) consisting of chemotherapy followed by surgery with radiation (n = 26) and without radiation (n = 7). Fifty-seven patients received other therapies (nonNEO). Treatments received by the nonNEO group consisted of chemotherapy, radiation, mastectomy, adrenalectomy, and oophorectomy, alone or in combination. The median follow-up was 28.9 months for the NEO group and 17.6 months for the nonNEO group. Borderline significant differences in the OS distributions between the two groups were found (P = .10), with 3- and 5-year OS for the NEO group of 40.0% and 29.9% and for the nonNEO group of 24.7% and 16.5%, respectively. DFS and LC were comparable in the two groups. Lower stage was associated with an improved OS (P < .05). The 5-year OS for stage IIIB was 30.9%, compared to 7.8% for stage TV. In those patients with stage III disease who were treated with mastectomy and rendered free of disease, margin status was identified by univariate analysis to be a prognostic indicator for OS (P < .05). The 3-year OS, DFS, and LC for patients with negative margins were 47.4%, 37.5%, and 60.3%, respectively, compared to 0%, 16.7%, and 31.3% in patients with positive margins. Conclusions: This study suggests that in patients with inflammatory breast cancer and nonmetastatic disease, an aggressive surgical approach may be justified with the goal of a negative surgical margin. Achievement of this local control is associated with a better overall outcome for this subset of patients. The ability to obtain negative margins may further identify a group of patients with a less aggressive tumor biology that may be more responsive to other modalities of therapy. C1 Keesler Med Ctr, SGCS, MSGS 81st, Dept Gen Surg, Keesler AFB, MS 39534 USA. City Hope Natl Med Ctr, Dept Med Oncol, Los Angeles, CA USA. City Hope Natl Med Ctr, Dept Therapeut & Biostat, Los Angeles, CA USA. City Hope Natl Med Ctr, Dept Gen & Oncol Surg, Los Angeles, CA USA. RP Curcio, LD (reprint author), Keesler Med Ctr, SGCS, MSGS 81st, Dept Gen Surg, 301 Fisher St, Keesler AFB, MS 39534 USA. NR 25 TC 28 Z9 31 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1068-9265 J9 ANN SURG ONCOL JI Ann. Surg. Oncol. PD APR-MAY PY 1999 VL 6 IS 3 BP 249 EP 254 DI 10.1007/s10434-999-0249-3 PG 6 WC Oncology; Surgery SC Oncology; Surgery GA 194DV UT WOS:000080177600007 PM 10340883 ER PT J AU Barnard, KJ White, CE Absi, AE AF Barnard, KJ White, CE Absi, AE TI Two-dimensional restoration of motion-degraded intensified CCD imagery SO APPLIED OPTICS LA English DT Article ID OPTICAL TRANSFER-FUNCTIONS; MECHANICAL VIBRATIONS; NUMERICAL-CALCULATION; BLURRED IMAGES AB A Wiener filter-based deconvolution algorithm is developed to restore vibration-degraded video imagery from an intensified CCD camera. The method is based on the use of azimuth and elevation angular optical line-of-sight data recorded from external sensors to estimate a two-dimensional vibration-blur impulse response on a per frame basis. Flight conditions are reproduced in the laboratory by use of prerecorded in-fight vibration data. The performance of the algorithm varies from frame to frame, following the time-varying characteristics of the vibration-blur impulse response. However, real-time display of the restored video minimizes these effects because of eye integration, and near-full restoration of the original uncorrupted imagery is observed for both high-light- and low-light-level conditions with minimal amplification of noise. (C) 1999 Optical Society of America. C1 USAF, Sensors Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. Optimetr Inc, Ann Arbor, MI 48104 USA. RP Barnard, KJ (reprint author), USAF, Sensors Directorate, Res Lab, Bldg 622,3109 P St, Wright Patterson AFB, OH 45433 USA. NR 25 TC 5 Z9 5 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 1 PY 1999 VL 38 IS 10 BP 1942 EP 1952 DI 10.1364/AO.38.001942 PG 11 WC Optics SC Optics GA 184TU UT WOS:000079630200006 PM 18319749 ER PT J AU Olivas, JD Acosta, E Barrera, EV AF Olivas, JD Acosta, E Barrera, EV TI Surface study of the bonding nature of ambient adsorbates to nickel alloy substrates using thermal desorption and X-ray photoelectron spectroscopy SO APPLIED SURFACE SCIENCE LA English DT Article DE X-ray photoelectron spectroscopy; contamination; desorption; cleaning ID CHEMISORBED CO; XPS; SPECTRA; DECOMPOSITION; ADSORPTION; ALUMINUM; TITANIUM AB The present study analyzed the surface effects resulting from cleaning of a Ni alloy with different solvents using an approach involving thermal desorption and X-ray photoelectron spectroscopy. The study focused on contaminant O and C species interactions with the polycrystalline substrate resulting from various solvent/ambient interactions. Each solvent resulted in evaporation and ambient adsorption behavior which produced contaminants characteristic of the solvent used. Combining desorption theory and surface spectroscopic techniques, a method of determining desorption behavior, independent of weight measurements, was developed. By comparison of ambient O species to substrate oxides, changes in adsorbate coverage were estimated for the denuding surfaces. Experimental values for desorption behaviors and relative desorption energetics were determined for ambient air on a polycrystalline substrate resulting from solvent/substrate interactions. Differences were discriminated between the preparation methods and shown to vary as a function of solvent used. The nature of a surface with contamination was explained on this basis. (C) 1999 Elsevier Science B.V. All rights reserved. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91101 USA. Div Phys Sci, Kelly AFB, TX 78241 USA. Rice Univ, Rice Quantum Inst, Dept Mech Engn & Mat Sci, Houston, TX 77005 USA. RP Olivas, JD (reprint author), NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. NR 40 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD APR PY 1999 VL 143 IS 1-4 BP 153 EP 168 DI 10.1016/S0169-4332(98)00373-0 PG 16 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 192JB UT WOS:000080074200020 ER PT J AU He, ZQ Spain, JC AF He, ZQ Spain, JC TI Comparison of the downstream pathways for degradation of nitrobenzene by Pseudomonas pseudoalcaligenes JS45 (2-aminophenol pathway) and by Comamonas sp. JS765 (catechol pathway) SO ARCHIVES OF MICROBIOLOGY LA English DT Article DE nitrobenzene; 2-aminophenol; catechol; 2-aminomuconate; meta-cleavage pathway; biodegradation ID META-CLEAVAGE PATHWAY; BENZALDEHYDE DEHYDROGENASE; PUTIDA; BIODEGRADATION; SEMIALDEHYDE; PURIFICATION; ENZYMES; 1,6-DIOXYGENASE; DECARBOXYLASE; METABOLISM AB Nitrobenzene is degraded by Pseudomonas pseudoalcaligenes JS45 via 2-aminophenol to 2-aminomuconic semialdehyde, which is further degraded to pyruvate and acetaldehyde. Comamonas sp. JS765 degrades nitrobenzene via catechol to 2-hydroxymuconic semialdehyde. In this study we examined and compared the late steps of degradation of nitrobenzene by these two microorganisms in order to reveal the biochemical relationships of the two pathways and to provide insight fur further investigation of their evolutionary history. Experiments showed that 2-hydroxymuconate, the product of the dehydrogenation of 2-hydroxymuconic semialdehyde, was degraded to pyruvate and acetaldehyde by crude extracts of Comamonas sp. JS765, which indicated the operation of a classical catechol meta-cleavage pathway. The semialdehyde dehydrogenases from Comamonas sp. JS765 and P. pseudoalcaligenes JS45 were able to metabolize both 2-amino- and 2-hydroxymuconic semialdehyde, with strong preference for the physiological substrate. 2-Aminomuconate was not a substrate for 4-oxalocrotonate decarboxylase from either bacterial strain. The close biochemical relationships among the classical catechol meta-cleavage pathway in Comamonas sp. JS765, 2-aminophenol meta-cleavage pathways in P. pseudoalcaligenes JS45, and an alternative 2-aminophenol meta-cleavage pathway in Pseudomonas sp. AP-3 suggest a common evolutionary origin. C1 USAF, Res Lab, AFRL MLQR, Tyndall AFB, FL 32403 USA. RP Spain, JC (reprint author), USAF, Res Lab, AFRL MLQR, 139 Barnes Dr,Suite 2, Tyndall AFB, FL 32403 USA. OI He, Zhongqi/0000-0003-3507-5013 NR 33 TC 35 Z9 39 U1 0 U2 10 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0302-8933 J9 ARCH MICROBIOL JI Arch. Microbiol. PD APR PY 1999 VL 171 IS 5 BP 309 EP 316 DI 10.1007/s002030050715 PG 8 WC Microbiology SC Microbiology GA 192TJ UT WOS:000080094900003 PM 10382261 ER PT J AU Morgan, G AF Morgan, G TI Neurology was there - 1960 SO ARCHIVES OF NEUROLOGY LA English DT Article AB In 1960, the general presidential election introduced television as a critical factor in the election process as a series of 4 television debates between John F. Kennedy and Richard Nixon was scheduled. Kennedy won the November election, embarking on a new age of emphasis on technological advancement for the United States. The struggle between the Western and Communist. worlds dominated the international scene as the world was deep in the midst. of the Cold War. On May 1, 1960, an American U2 pilot's plane was shot down over the Soviet Union. He was eventually convicted of treason and sentenced to 10 years in prison in the Soviet Union. Nikita Khruschev demanded reorganization of the United Nations and warned the United States that if it interfered with Cuba there would be rocket attacks.(1) Neurology was there. C1 Uniformed Serv Univ Hlth Sci, Dept Neurol, Bethesda, MD 20814 USA. RP Morgan, G (reprint author), SGOMU, MDOS 89, 1050 W Perimeter Rd,Suite FB7, Andrews AFB, MD 20762 USA. NR 13 TC 0 Z9 0 U1 1 U2 1 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0003-9942 J9 ARCH NEUROL-CHICAGO JI Arch. Neurol. PD APR PY 1999 VL 56 IS 4 BP 488 EP 490 DI 10.1001/archneur.56.4.488 PG 3 WC Clinical Neurology SC Neurosciences & Neurology GA 184NA UT WOS:000079617200017 PM 10199341 ER PT J AU Carter, RM Mansfield, JT AF Carter, RM Mansfield, JT TI A sensitive bladder: An atypical presentation of cancer in a US Army pilot SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE carcinoma; papillary carcinoma; transitional cell urinary bladder transitional cell carcinoma AB Bladder cancer is the most common cancer in the urinary tract, the vast majority (90%) of which are transitional cell carcinomas. A papilloma (grade I) lesion offers an excellent prognosis after excision, though recurrence is possible. The classic sign of bladder cancer is gross, painless hematuria. We report a case of transitional cell papillary carcinoma in an aircrew member with atypical presentation: irritative voiding symptoms without hematuria. With a careful history and physical, and aggressive clinical suspicion, an early diagnosis was made offering an excellent prognosis. The patient, an Army helicopter pilot, returned to flight status with a waiver. C1 WAATS, Aeromed Serv, Marana, AZ 85653 USA. ACC, Med Operat Squadron 355, Davis Monthan AFB, AZ USA. RP Carter, RM (reprint author), WAATS, Aeromed Serv, Marana, AZ 85653 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD APR PY 1999 VL 70 IS 4 BP 335 EP 337 PG 3 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 181RX UT WOS:000079457000007 PM 10223269 ER PT J AU Pond, WW AF Pond, WW TI Untitled SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Letter C1 USAF, Grissom AFB, IN 46971 USA. RP Pond, WW (reprint author), USAF, Grissom AFB, IN 46971 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD APR PY 1999 VL 70 IS 4 BP 356 EP 356 PG 1 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 181RX UT WOS:000079457000011 PM 10223275 ER PT J AU O'Loughlin, EJ Sims, GK Traina, SJ AF O'Loughlin, EJ Sims, GK Traina, SJ TI Biodegradation of 2-methyl, 2-ethyl, and 2-hydroxypyridine by an Arthrobacter sp isolated from subsurface sediment SO BIODEGRADATION LA English DT Article DE 2-ethylpyridine; 2-hydroxypyridine; 2-methylpyridine; biodegradation; N-heterocycles ID QUINOLINE-DEGRADING BACTERIA; SHALE RETORT WATER; MICROBIAL TRANSFORMATION; MICROCOCCUS-LUTEUS; ORGANIC SOLUTES; PYRIDINE RING; DEGRADATION; GROUNDWATER; SOIL; METABOLISM AB A bacterium capable of degrading 2-methylpyridine was isolated by enrichment techniques from subsurface sediments collected from an aquifer located at an industrial site that had been contaminated with pyridine and pyridine derivatives. The isolate, identified as an Arthrobacter sp., was capable of utilizing 2-methylpyridine, 2-ethylpyridine, and 2-hydroxypyridine as primary C, N, and energy sources. The isolate was also able to utilize 2-, 3-, and 4-hydroxybenzoate, gentisic acid, protocatechuic acid and catechol, suggesting that it possesses a number of enzymatic pathways for the degradation of aromatic compounds. Degradation of 2-methylpyridine, 2-ethylpyridine, and 2-hydroxypyridine was accompanied by growth of the isolate and release of ammonium into the medium. Degradation of 2-methylpyridine was accompanied by overproduction of riboflavin. A soluble blue pigment was produced by the isolate during the degradation of 2-hydroxypyridine, and may be related to the diazadiphenoquinones reportedly produced by other Arthrobacter spp. when grown on 2-hydroxypyridine. When provided with 2-methylpyridine, 2-ethylpyridine, and 2-hydroxypyridine simultaneously, 2-hydroxypyridine was rapidly and preferentially degraded; however there was no apparent biodegradation of either 2-methylpyridine or 2-ethylpyridine until after a seven day lag. The data suggest that there are differences between the pathway for 2-hydroxypyridine degradation and the pathway(s) for 2-methylpyridine and 2-ethylpyridine. C1 Ohio State Univ, Sch Nat Resources, Columbus, OH 43210 USA. RP O'Loughlin, EJ (reprint author), USAF, Res Lab, MLQR, 139 Barnes Dr,Suite 2, Tyndall AFB, FL 32403 USA. RI Sims, Gerald/A-2500-2008; O'Loughlin, Edward/C-9565-2013 OI O'Loughlin, Edward/0000-0003-1607-9529 NR 53 TC 25 Z9 32 U1 1 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0923-9820 J9 BIODEGRADATION JI Biodegradation PD APR PY 1999 VL 10 IS 2 BP 93 EP 104 DI 10.1023/A:1008309026751 PG 12 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 209QP UT WOS:000081060000002 PM 10466198 ER PT J AU Walls, JG Hong, G Cox, JE McCabe, KM O'Brien, KE Allerton, JP Derdak, S AF Walls, JG Hong, G Cox, JE McCabe, KM O'Brien, KE Allerton, JP Derdak, S TI Pulmonary intravascular - Lymphomatosis presentation with dyspnea and air trapping SO CHEST LA English DT Article DE air trapping; high-resolution CT; intravascular lymphomatosis; mosaic perfusion ID LARGE-CELL LYMPHOMA; MALIGNANT ANGIOENDOTHELIOMATOSIS; LUNG-DISEASE AB Intravascular lymphomatosis (NL) is a rare lymphoid neoplasm that is typically of B-cell lineage and characterized by proliferation of malignant cells within small arterioles, capillaries, and venules, We report a patient with pulmonary IVL who presented clinically with progressive dyspnea, fever, and a dry cough. Pulmonary function tests revealed a marked decrease in diffusion capacity with airflow obstruction and severe air trapping. High-resolution CT (HRCT) of the chest with inspiratory and expiratory images revealed mosaic attenuation consistent with air trapping. Transbronchial biopsies revealed the diagnosis of NL with capillary expansion in the alveolar and peribronchiolar interstitial tissue, IVL should be considered in the differential diagnosis of a patient with an interstitial lung disease, air trapping on pulmonary function tests, and mosaic attenuation on HRCT. Transbronchial biopsies may be the initial diagnostic procedure of choice. C1 Wilford Hall USAF Med Ctr, Dept Pulm Crit Care, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Hematol Oncol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Pathol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Internal Med, Lackland AFB, TX 78236 USA. RP Walls, JG (reprint author), Wilford Hall USAF Med Ctr, Dept Pulm Crit Care Med, MMCP, MC, 2200 Berquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 15 TC 30 Z9 33 U1 0 U2 0 PU AMER COLL CHEST PHYSICIANS PI NORTHBROOK PA 3300 DUNDEE ROAD, NORTHBROOK, IL 60062-2348 USA SN 0012-3692 J9 CHEST JI Chest PD APR PY 1999 VL 115 IS 4 BP 1207 EP 1210 DI 10.1378/chest.115.4.1207 PG 6 WC Critical Care Medicine; Respiratory System SC General & Internal Medicine; Respiratory System GA 185EV UT WOS:000079655900055 PM 10208234 ER PT J AU Watson, KA Lyons, KM Donbar, JM Carter, CD AF Watson, KA Lyons, KM Donbar, JM Carter, CD TI Scalar and velocity field measurements in a lifted CH4-air diffusion flame SO COMBUSTION AND FLAME LA English DT Article ID TURBULENT-JET FLAMES; BLOWOUT; STABILIZATION; LIFTOFF AB Experiments have been performed to investigate the leading edge of a lifted jet diffusion flame. The first portion of this study is a simultaneous particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF) investigation of a lifted methane dame. The simultaneous technique is an approach for establishing the 2-D velocity field in conjunction with the flame front location indicated by laser-induced fluorescence from CH radicals within the reaction zone. The results show that the lifted flame stabilizes in a region of relatively low incoming gas velocity. Furthermore, the radial movement of large-scale vortices appears to play a crucial role in local flame extinction. The second set of experiments involves a simultaneous CH and OH PLIF investigation of the same lifted flame. The relative positions of the two radical fields have remarkable agreement. The CH profile is indicative of the fuel-rich region of the reaction zone and closely follows the inner edge of the OH profile. Furthermore, the OH zone is more than three times as thick as the CH zone, and the structures in both images support the radial motion of vortices established by the joint PIV/CH-PLIF measurements. (C) 1999 by The Combustion Institute. C1 N Carolina State Univ, Dept Mech & Aerosp Engn, Raleigh, NC 27695 USA. USAF, Wright Lab, Aero Prop & Power Directorate, Wright Patterson AFB, OH 45433 USA. Innovat Sci Solut Inc, Dayton, OH 45440 USA. RP Lyons, KM (reprint author), N Carolina State Univ, Dept Mech & Aerosp Engn, Box 7910, Raleigh, NC 27695 USA. EM lyons@eos.ncsu.edu NR 34 TC 84 Z9 85 U1 1 U2 8 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD APR PY 1999 VL 117 IS 1-2 BP 257 EP 271 DI 10.1016/S0010-2180(98)00086-8 PG 15 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 162UX UT WOS:000078366200015 ER PT J AU Elmer, KB George, RM AF Elmer, KB George, RM TI Herpes zoster in a 7-month old infant: A case report and review SO CUTIS LA English DT Article ID EPIDEMIOLOGY; INFECTION AB Herpes tester (HZ) is a cutaneous viral infection of the skin that presents in a dermatomal distribution. It represents reactivation of herpes varicella zoster virus that has continued to exist in a latent form in the neurons of the posterior root ganglia. Although it is rare to see HZ in children, cases have been reported after exposure to varicella zoster in utero or during the first months of life. We present a case of HZ in a healthy 7-month-old girl who had had chickenpox at age 4 months. C1 USAF, Dermatol Serv, Yokota AFB, Japan. RP Elmer, KB (reprint author), USAF, Dermatol Serv, Yokota AFB, Japan. NR 8 TC 6 Z9 6 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD APR PY 1999 VL 63 IS 4 BP 217 EP 218 PG 2 WC Dermatology SC Dermatology GA 187LZ UT WOS:000079789200007 PM 10228750 ER PT J AU Nishino, SF Spain, JC Lenke, H Knackmuss, HJ AF Nishino, SF Spain, JC Lenke, H Knackmuss, HJ TI Mineralization of 2,4- and 2,6-dinitrotoluene in soil slurries SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CONTAMINATED SOIL; PSEUDOMONAS SP; BIODEGRADATION; 2,4-DINITROTOLUENE; BACTERIA; BIOREMEDIATION; RESIDUES; AQUIFER; DNT AB DNT-degrading bacteria can completely degrade mixtures of DNT in liquid cultures without the production of aminonitrotoluenes. We determined whether specific DNT-degrading isolates could also degrade DNT from contaminated soil in the presence of indigenous microbial communities. When 2,4-DNT- and 2,6-DNT-degrading strains were added to a mixture of 2,4-DNT and 2,6-DNT in a soil slurry, disappearance of DNT was accompanied by (CO2)-C-14 release and stoichiometric appearance of nitrite. When soil historically contaminated with mixed DNT isomers was used in slurries, the combination of DNT-degrading strains removed all of the DNT from the aqueous phase and over 99% of the initial DNT. Traces of extractable DNT remained associated with the soil; however, the toxicity of the treated soil was low. After an extended acclimation period, the 2,4-DNT, and, much later, the 2,6-DNT, was degraded in the uninoculated control. The results show that aged DNT contamination can be removed effectively from soil. The addition of specific DNT-mineralizing bacteria dramatically enhances the mineralization of DNT in soil slurries. Native bacteria do not convert DNT to aminonitrotoluenes during the short incubation times required for mineralization of DNT. C1 USAF, Res Lab, Tyndall AFB, FL 32403 USA. Fraunhofer Inst Grenzflachen & Bioverfahrenstech, D-70569 Stuttgart, Germany. RP Spain, JC (reprint author), USAF, Res Lab, MLQR,139 Barnes Dr,Suite 2, Tyndall AFB, FL 32403 USA. EM Jim.Spain@mlq.afrl.af.mil NR 30 TC 45 Z9 49 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X EI 1520-5851 J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD APR 1 PY 1999 VL 33 IS 7 BP 1060 EP 1064 DI 10.1021/es9808301 PG 5 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 183FG UT WOS:000079543100031 ER PT J AU O'Loughlin, EJ Burris, DR Delcomyn, CA AF O'Loughlin, EJ Burris, DR Delcomyn, CA TI Reductive dechlorination of trichloroethene mediated by humic-metal complexes SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID HOMOGENEOUS AQUEOUS-SOLUTION; CARBON-TETRACHLORIDE; ORGANIC-MATTER; TETRACHLOROETHYLENE; DEHALOGENATION; KINETICS; VITAMIN-B-12; ELIMINATION; COENZYMES; ETHANES AB Experiments were conducted to determine if transition metal-humic acid complexes can act as e-transfer mediators in the reductive dechlorination of trichloroethene (TCE) using Ti(lll) citrate as the bulk reductant. In the presence of Ni-Aldrich humic acid (AHA) complexes, TCE reduction was rapid, with complete removal of TCE in less than 23 h. Cu-AHA complexes were less effective as e(-) mediators than NI-AHA complexes; only 60% of TCE was reduced after 150 h. Partially dechlorinated intermediates were observed during TCE reduction; however, they were transitory, and at no time accounted for more than 2% of the initial TCE mass on a mole C basis. Ethane and ethene were the primary end products of TCE reduction; however, a suite of other non-chlorinated hydrocarbons consisting of methane and C-3 to C-6 alkanes and alkenes were also observed. The results suggest that humic-metal complexes may represent a previously unrecognized class of electron mediators in natural environments. C1 USAF, Res Lab, Tyndall AFB, FL 32403 USA. Appl Res Associates Inc, Tyndall AFB, FL 32403 USA. RP O'Loughlin, EJ (reprint author), USAF, Res Lab, AFRL MLQR,139 Barnes Dr, Tyndall AFB, FL 32403 USA. RI O'Loughlin, Edward/C-9565-2013 OI O'Loughlin, Edward/0000-0003-1607-9529 NR 22 TC 35 Z9 37 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD APR 1 PY 1999 VL 33 IS 7 BP 1145 EP 1147 DI 10.1021/es9810033 PG 3 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 183FG UT WOS:000079543100044 ER PT J AU Lang, M Marci, G AF Lang, M Marci, G TI The influence of single and multiple overloads on fatigue crack propagation SO FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES LA English DT Article DE fatigue crack propagation; retardation; load interaction; overload; residual stress; crack closure; Delta K-eff concept; aluminium alloy ID CLOSURE AB The effects of single and multiple overloads on fatigue crack propagation were studied experimentally using the aluminium alloy Al 7475-T7351. The crack propagation stress intensity factor, K-PR, was determined after each single and multiple overload sequence. The variation of K-PR With the overload parameters can be described by an empirical relationship that unifies the experimental data obtained under a variety of loading conditions. Observations made in the study suggest that load interaction effects are controlled by residual compressive stresses ahead of the crack tip, with fatigue crack closure playing only a secondary role. C1 USAF, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. DLR, German Aerosp Ctr, Inst Mat Res, D-51147 Cologne, Germany. RP Lang, M (reprint author), USAF, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 51 TC 39 Z9 39 U1 2 U2 8 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 8756-758X J9 FATIGUE FRACT ENG M JI Fatigue Fract. Eng. Mater. Struct. PD APR PY 1999 VL 22 IS 4 BP 257 EP 271 DI 10.1046/j.1460-2695.1999.00165.x PG 15 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 202PU UT WOS:000080662000001 ER PT J AU Lee, JG Weller, DA Vigil, HT Romano, P Kravitz, R Sweeney, B Schutz, S Saavedra, S Leung, JW AF Lee, JG Weller, DA Vigil, HT Romano, P Kravitz, R Sweeney, B Schutz, S Saavedra, S Leung, JW TI Multicenter, randomized, controlled, outcome study of open access (OA) endoscopy SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Univ Calif Davis, Med Ctr, Sacramento, CA 95817 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RI Romano, Patrick/N-4225-2014 OI Romano, Patrick/0000-0001-6749-3979 NR 0 TC 4 Z9 4 U1 0 U2 3 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 1999 VL 49 IS 4 MA 364 BP AB145 EP AB145 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 188LH UT WOS:000079848100363 ER PT J AU Narayani, RI Schutz, SM Kobes, PJ Weller, D AF Narayani, RI Schutz, SM Kobes, PJ Weller, D TI Successful endoscopic pancreatic duct therapy (TX) for "smoldering pancreatitis'': A case series. SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 1999 VL 49 IS 4 MA 650 BP AB222 EP AB222 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 188LH UT WOS:000079848100649 ER PT J AU Owens, GR Lievens, MW Lang, KA AF Owens, GR Lievens, MW Lang, KA TI Aspirin use and rise of post-colonoscopy/polypectomy hemorrhage SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Uniformed Serv Hlth Care Consortium, Lackland AFB, TX USA. 81st Med Grp, Keesler AFB, MS USA. 59th Med Wing, Lackland AFB, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 1999 VL 49 IS 4 MA 107 BP AB76 EP AB76 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 188LH UT WOS:000079848100108 ER PT J AU Schutz, S Abbott, R AF Schutz, S Abbott, R TI Grading ERCPs by degree of difficulty: A new concept to produce more meaningful outcome data SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 1999 VL 49 IS 4 MA 375 BP AB148 EP AB148 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 188LH UT WOS:000079848100374 ER PT J AU Sweeney, BF Lang, KA O'Brien, K AF Sweeney, BF Lang, KA O'Brien, K TI Incidence of advanced proximal neoplasia in patients with adenomas found on screening flexible sigmoidoscopy SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 1999 VL 49 IS 4 MA 82 BP AB69 EP AB69 PN 2 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 188LH UT WOS:000079848100083 ER PT J AU Roach, WP Johnson, TE Rockwell, BA AF Roach, WP Johnson, TE Rockwell, BA TI Proposed maximum permissible exposure limits for ultrashort laser pulses SO HEALTH PHYSICS LA English DT Article DE lasers; radiation, nonionizing; safety standards; maximum permissible exposures ID VISIBLE RETINAL LESIONS; DAMAGE AB Recent studies have provided considerable ED50 data for both visible and near infrared wavelengths from single laser pulses below one nanosecond of exposure. The current ANSI Z136.1 standard does not offer an approved maximum permissible exposure limit for subnanosecond single laser pulses and the current suggested maximum permissible exposure limit mag be overly conservative, Lacking an approved standard industrial, medical, educational, and military uses of these types of laser systems may be limited or prohibited, A new set of laser maximum permissible exposure limits for subnanosecond visible and near infrared single laser pulses is recommended, along with the steps taken to develop the proposed standard. C1 Uniformed Serv Univ Hlth Sci, Dept Prevent Med & Biometr, Bethesda, MD 20814 USA. USAF, Res Lab, AFRL HEDO, Brooks AFB, TX 78235 USA. NR 23 TC 20 Z9 20 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD APR PY 1999 VL 76 IS 4 BP 349 EP 354 DI 10.1097/00004032-199904000-00002 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 175RM UT WOS:000079108800002 PM 10086595 ER PT J AU Mailloux, RJ AF Mailloux, RJ TI In memoriam: Philipp Blacksmith, 1921-1999 SO IEEE ANTENNAS AND PROPAGATION MAGAZINE LA English DT Biographical-Item C1 USAF, Res Lab, SN, Div Electromagnet Technol, Hanscom AFB, MA 01731 USA. RP Mailloux, RJ (reprint author), USAF, Res Lab, SN, Div Electromagnet Technol, 31 Grenier St, Hanscom AFB, MA 01731 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9243 J9 IEEE ANTENNAS PROPAG JI IEEE Antennas Propag. Mag. PD APR PY 1999 VL 41 IS 2 BP 112 EP 112 DI 10.1109/MAP.1999.769697 PG 1 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 205FY UT WOS:000080811700018 ER PT J AU Stogdill, RC AF Stogdill, RC TI Dealing with obsolete parts SO IEEE DESIGN & TEST OF COMPUTERS LA English DT Article AB The US Air Force has launched an initiative to develop an affordable, systematic approach to dealing with obsolete electronic parts. In addition to management and reengineering tools, the initiative is developing reliability models for commercially manufactured electronics used in defense systems. C1 USAF, Res Lab, Mat & Mfg Directorate, Mfg Technol Branch, Wright Patterson AFB, OH 45433 USA. RP Stogdill, RC (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Mfg Technol Branch, Area B,Bldg 653,2977 P St,Suite 6, Wright Patterson AFB, OH 45433 USA. NR 4 TC 20 Z9 20 U1 1 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0740-7475 J9 IEEE DES TEST COMPUT JI IEEE Des. Test Comput. PD APR-JUN PY 1999 VL 16 IS 2 BP 17 EP 25 DI 10.1109/54.765200 PG 9 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 195DH UT WOS:000080233500005 ER PT J AU Madisetti, VK Jung, YK Khan, MH Kim, J Finnessy, T AF Madisetti, VK Jung, YK Khan, MH Kim, J Finnessy, T TI Reengineering legacy embedded systems SO IEEE DESIGN & TEST OF COMPUTERS LA English DT Article AB Systems that require reengineering are a fact of life in both the commercial and military arenas. The authors have developed a systematic methodology based on virtual prototyping, with accompanying tools and libraries, for rapidly upgrading electronic systems. C1 VP Technol, Marietta, GA 30068 USA. USAF, Mfg Technol Directorate, Mfg & Engn Syst Branch, Wright Patterson AFB, OH USA. RP Madisetti, VK (reprint author), VP Technol, POB 680190, Marietta, GA 30068 USA. NR 2 TC 2 Z9 2 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0740-7475 J9 IEEE DES TEST COMPUT JI IEEE Des. Test Comput. PD APR-JUN PY 1999 VL 16 IS 2 BP 38 EP 47 DI 10.1109/54.765202 PG 10 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 195DH UT WOS:000080233500007 ER PT J AU Sheppard, ST Doverspike, K Pribble, WL Allen, ST Palmour, JW Kehias, LT Jenkins, TJ AF Sheppard, ST Doverspike, K Pribble, WL Allen, ST Palmour, JW Kehias, LT Jenkins, TJ TI High-power microwave GaN/AlGaN HEMT's on semi-insulating silicon carbide substrates SO IEEE ELECTRON DEVICE LETTERS LA English DT Article DE heterojunctions; microwave power FET's; MODFET's AB Record performance of high-power GaN/Al0.14Ga0.86N high-electron mobility transistors (HEMT's) fabricated on semi-insulating (SI) 4H-SiC substrates is reported. Devices of 0.125-0.25 mm gate periphery show high CW power densities between 5.3 and 6.9 W/mm, with a typical power-added efficiency (PAE) of 35.4% and an associated gain of 9.2 dB at 10 GHz, High-electron mobility transistors with 1.5-mm gate widths (12 x 125 mu m), measured on-wafer, exhibit a total output power of 3.9 W CW (2.6 W/mm) at 10 GHz with a PAE of 29% and an associated gain of 10 dB at the -2 dB compression point. A 3-mm HEMT, packaged with a hybrid matching circuit, demonstrated 9.1 W CW at 7.4 GHz with a PAE of 29.6% and a gain of 7.1 dB, These data represent the highest power density, total power, and associated gain demonstrated for a III-Nitride HEMT under RF drive. C1 Cree Res Inc, Durham, NC 27703 USA. USAF, RL, SNDM, Wright Patterson AFB, OH 45433 USA. RP Sheppard, ST (reprint author), Cree Res Inc, Durham, NC 27703 USA. NR 10 TC 392 Z9 402 U1 11 U2 120 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0741-3106 J9 IEEE ELECTR DEVICE L JI IEEE Electron Device Lett. PD APR PY 1999 VL 20 IS 4 BP 161 EP 163 DI 10.1109/55.753753 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 181MG UT WOS:000079444700005 ER PT J AU Iaconis, C Walmsley, IA AF Iaconis, C Walmsley, IA TI Self-referencing spectral interferometry for measuring ultrashort optical pulses SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE pulse characterization; pulse measurements; pulse reconstruction; ultrafast optics ID FEMTOSECOND PULSES; PHASE AB This paper describes a novel self-referencing interferometric method for measuring the time-dependent intensity and phase of ultrashort optical pulses. The technique, spectral phase interferometry for direct electric-field reconstruction (SPIDER), measures the interference between a pair of spectrally sheared replicas of the input pulse. Direct (noniterative) inversion of the interferogram yields the electric field of the input pulse without ambiguity. The interferogram, which is solely a function of frequency, is resolved with a spectrometer and recorded with a slow detector. Moreover, the geometry is entirely collinear and requires no moving components. This paper describes in detail the principle of operation, apparatus, and calibration of SPIDER and gives experimental examples of reconstructed pulses. C1 Univ Rochester, Inst Opt, Rochester, NY 14627 USA. USAF, Phillips Lab, DELO, AFRL, Kirtland AFB, NM 87117 USA. RP Iaconis, C (reprint author), Univ Rochester, Inst Opt, Rochester, NY 14627 USA. NR 19 TC 347 Z9 361 U1 16 U2 66 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD APR PY 1999 VL 35 IS 4 BP 501 EP 509 DI 10.1109/3.753654 PG 9 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 181CV UT WOS:000079423800011 ER PT J AU Patti, JJ Husnay, RM Pintar, J AF Patti, JJ Husnay, RM Pintar, J TI A smart software radio: Concept development and demonstration SO IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS LA English DT Article DE adaptive signal detection; communication systems; digital communication; digital radio; spread-spectrum communication AB A testbed system was developed for smart networking radio algorithms. The associated modular software environment and Phase I hardware testbed are described. It provides the framework for the development of advanced processing algorithms, adaptive multirate systems, and operational radio algorithms and modules. Modular software radio technology allows for the insertion of new algorithms, the quantitative characterization of waveform performance, and the separation of the waveform definition from the details of the implementation to enhance portability. The testbed is representative of SPEAKeasy II-class open architecture software radios. The FLIP-WAVE spread-spectrum modem invented at the U,S, Air Force Research Laboratory (AFRL) was developed and evaluated using this testbed. The waveform is presented with experimental results. A unique feature of this modem is a new single-channel quadraphase differential RAKE: receiver processor, which illustrates the contributions of the testbed toward the flexibility and portability of novel modems. C1 USAF, Res Lab, Rome, NY 13441 USA. Rome Res Corp, Rome, NY 13441 USA. RP Patti, JJ (reprint author), USAF, Res Lab, Rome, NY 13441 USA. NR 9 TC 11 Z9 11 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0733-8716 J9 IEEE J SEL AREA COMM JI IEEE J. Sel. Areas Commun. PD APR PY 1999 VL 17 IS 4 BP 631 EP 649 DI 10.1109/49.761041 PG 19 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 192FT UT WOS:000080068400010 ER PT J AU Lach, SR Amin, MG Lindsey, AR AF Lach, SR Amin, MG Lindsey, AR TI Broadband interference excision for software-radio spread-spectrum communications using time-frequency distribution synthesis SO IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS LA English DT Article DE interference excision; software radio; spread spectrum; time frequency; Wigner distribution ID WIGNER DISTRIBUTION AB A new method is introduced for interference excision in spread-spectrum communications that is conducive to software-radio applications. Spare processing capacity in the receiver permits the use of time-frequency techniques to synthesize a nonstationary interference from the time-frequency domain using least squares methods. The synthesized signal is then subtracted from the incoming data in the time domain, leading to jammer removal and increased signal-to-interference-and-noise ratio at the input of the correlator, The paper focuses on jammers with constant modulus that are uniquely described by their instantaneous frequency characteristics. With this a priori knowledge, the jammer signal amplitude is restored by projecting each sample of the synthesized signal to a circle representing its constant modulus. With the phase matching provided by the least squares synthesis method and amplitude matching underlying the projection operation, a significant improvement in receiver performance/bit-error rates is achieved over the case where no projection is performed. Software-radio aspects including computational complexity and processing modes are also discussed. C1 Villanova Univ, Dept Elect & Comp Engn, Villanova, PA 19085 USA. Rome Lab, RL C3BB, Rome, NY 13441 USA. RP Lach, SR (reprint author), USAF, Res Lab, Eglin AFB, FL 32542 USA. NR 20 TC 18 Z9 23 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0733-8716 J9 IEEE J SEL AREA COMM JI IEEE J. Sel. Areas Commun. PD APR PY 1999 VL 17 IS 4 BP 704 EP 714 DI 10.1109/49.761046 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 192FT UT WOS:000080068400015 ER PT J AU Goldstein, JS Reed, IR Zulch, PA AF Goldstein, JS Reed, IR Zulch, PA TI Multistage partially adaptive STAP CFAR detection algorithm SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID SUBSPACE; SIGNAL; RADAR AB A new method of partially adaptive constant false-alarm rate (CFAR) detection is introduced. The processor implements a novel sequence of orthogonal subspace projections to decompose the Wiener solution in terms of the cross-correlation observed at each stage. The performance is evaluated using the general framework of space-time adaptive processing (STAP) for the cases of both known and unknown covariance. It is demonstrated that this new approach to partially adaptive STAP outperforms the more complex eigen-analysis approaches using both simulated DARPA Mountain Top data and true pulse-Doppler radar data collected by the MCARM radar. C1 Univ So Calif, Dept Elect Engn, Los Angeles, CA 90089 USA. USAF, Res Lab, SNRT, Rome, NY 13441 USA. MIT, Lincoln Lab, Cambridge, MA 02139 USA. RP Goldstein, JS (reprint author), SAIC, 4001 N Fairfax Dr,Suite 400, Arlington, VA 22203 USA. NR 51 TC 70 Z9 81 U1 0 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 1999 VL 35 IS 2 BP 645 EP 661 DI 10.1109/7.766945 PG 17 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 199CK UT WOS:000080461600023 ER PT J AU Reynolds, OR Pachter, M AF Reynolds, OR Pachter, M TI Phasor approach to continuous-time system identification SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article AB In this work, continuous-time systems are considered, and an innovative system identification approach is applied in the frequency domain, where phasor measurements, as provided by frequency analyzers, are used. This algorithm is obtained through a careful analysis of the physics of the measurement situation, following which the method of minimum variance (MV) estimation is iteratively applied in a linear regression framework. This process renders an efficient pseudominimum variance algorithm that is of linear prediction type and is superior to alternative methods. Thus, it is shown that the parameter estimate is a fixed point of a nonlinear mapping associated with the MV calculation, rather than the solution of an optimization problem. The simulation experiments are carefully performed, and the conditions are fully documented. C1 USAF, Inst Technol, ENG, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Reynolds, OR (reprint author), USAF, Inst Technol, ENG, Dept Elect & Comp Engn, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9251 EI 1557-9603 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 1999 VL 35 IS 2 BP 683 EP 699 DI 10.1109/7.766948 PG 17 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 199CK UT WOS:000080461600026 ER PT J AU Berger, SD Welsh, BM AF Berger, SD Welsh, BM TI Selecting a reduced-rank transformation for STAP - A direct form perspective SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID ADAPTIVE RADAR AB We introduce the signal-to-interference plus noise ratio (SINR) metric as a tool for selecting a rank reduction transformation that maximizes the output SINR of a direct form space-time adaptive professor. The SINR metric is used to identify the eigenvectors with the greatest impact on the output SINR which become the columns of the rank reduction transformation. The SINR metric method exhibits a graceful degradation in performance as the rank of the transformation approaches one. C1 USAF, Inst Technol, Dept Elect & Comp Engn, ENG, Wright Patterson AFB, OH 45433 USA. RP Berger, SD (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, ENG, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 9 TC 11 Z9 14 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD APR PY 1999 VL 35 IS 2 BP 722 EP 729 DI 10.1109/7.766952 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 199CK UT WOS:000080461600030 ER PT J AU Greenwood, AD Jin, JM AF Greenwood, AD Jin, JM TI A novel efficient algorithm for scattering from a complex BOR using mixed finite elements and cylindrical PML SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE body of revolution; electromagnetic scattering; finite-element method; perfectly matched layer ID ELECTROMAGNETIC SCATTERING; INHOMOGENEOUS BODIES; REVOLUTION; FORMULATION; MEDIA; BODY AB An efficient finite-element method (FEM) is developed to compute scattering from a complex body of revolution (BOR), The BOR is composed of perfect conductor and impedance surfaces and arbitrary inhomogeneous materials. The method uses edge-based vector basis functions to expand the transverse field components and node-based scalar basis functions to expand the angular component. The use of vector basis functions eliminates the problem of spurious solutions suffered by other three component FEM formulations. The FEM mesh is truncated with a perfectly matched layer (PR IL) in cylindrical coordinates. The use of PML in cylindrical coordinates avoids the wasted computation which results from a spherical mesh boundary with an elongated scatterer. The FEM equations are solved by ordering the unknowns with a reverse Cuthill-McKee algorithm and applying a banded-matrix solution algorithm, The method is capable of handling large, realistic radar targets, and good agreement with measured results is achieved for benchmark targets. C1 Univ Illinois, Ctr Computat Electromagnet, Dept Elect & Comp Engn, Urbana, IL 61801 USA. USAF, Res Lab, DEPE, Kirtland AFB, NM 87117 USA. RP Greenwood, AD (reprint author), Univ Illinois, Ctr Computat Electromagnet, Dept Elect & Comp Engn, Urbana, IL 61801 USA. NR 17 TC 27 Z9 29 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD APR PY 1999 VL 47 IS 4 BP 620 EP 629 DI 10.1109/8.768800 PG 10 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 205FH UT WOS:000080810300005 ER PT J AU Scholfield, DW Gahl, JM Shimomura, N AF Scholfield, DW Gahl, JM Shimomura, N TI Effective electric field for an arbitrary electromagnetic pulse SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE effective electric field; electromagnetic transient AB In the performance of intense electromagnetic transient, gaseous breakdown experiments, one parameter of interest is the effective electric field. A method of calculating the effective electric field for an arbitrary electromagnetic pulse is presented. This method is based upon the Laplace transform of the Lorentz force equation. Results from previous efforts are reproduced via this method and compared. Examples are calculated for various electromagnetic transients, most of which have never been calculated before. These examples of effective electric fields are used to generate theoretical Paschen curves, which are compared to experimental results. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Univ New Mexico, Dept Elect & Comp Engn, Albuquerque, NM 87131 USA. Univ Tokushima, Dept Elect & Elect Engn, Tokushima 770, Japan. RP Scholfield, DW (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RI Shimomura, Naoyuki/G-7036-2012 NR 12 TC 2 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD APR PY 1999 VL 27 IS 2 BP 628 EP 632 DI 10.1109/27.772295 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 211YM UT WOS:000081189500042 ER PT J AU Markgraf, SI Semples, J Wells, JR AF Markgraf, SI Semples, J Wells, JR TI The hydroxyl radical reaction rate constant and atmospheric transformation products of 2-propoxyethanol SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID GAS-PHASE REACTIONS; OH RADICALS; PROPOSED MECHANISM; ORGANIC-COMPOUNDS; METHYL NITRITE; OXIDATION; KINETICS; ETHER; TROPOSPHERE; NITRATE AB The relative rate technique has been used to measure the hydroxyl radical (OH) reaction rate constant of 2-propoxyethanol (2PEOH, CH3CH2CH2OCH2CH2(OH)). 2PEOH reacts with OH with a bimolecular rate constant of (21.4 +/- 6.0) X 10(-12) cm(3)molecule(-1)s(-1) at 297 +/-: 3 K and 1 atm total pressure, which is a little larger than previously reported [1]. Assuming an average OH concentration of 1 x 10(6) molecules cm(-3), an atmospheric lifetime of 13 h is calculated for 2PEOH. In order to more clearly define this hydroxy ether's atmospheric reaction mechanism, an investigation into the OH + 2PEOH reaction products was also conducted. The OH + 2PEOH reaction products and yields observed were: propyl formate (PF, 47 +/- 2%, CH3CH2CH2OC(=O)H), 2 propoxyethanal (CH3CH2CH2OCH2C(=O)H 15 +/- 1%), and 2-ethyl-1,3-dioxolane (5.4 +/- 0.4%). The 2PEOH reaction mechanism is discussed in light of current understanding of oxygenated hydrocarbon atmospheric chemistry. The Findings reported here can be related to other structurally similar alcohols and may impact regulatory tools such as ground-level ozone-forming potential calculations (incremental reactivity) [2]. (C) 1999 John Wiley & Sons, Inc. C1 Appl Res Assoc, Gulf Coast Div, Tyndall AFB, FL 32403 USA. Univ Florida, Dept Environm Engn Sci, Gainesville, FL 32611 USA. USAF, Res Lab, Airbase & Environm Technol Div, AFRL MLOR, Tyndall AFB, FL 32403 USA. RP Wells, JR (reprint author), Appl Res Assoc, Gulf Coast Div, POB 40128,Bldg 1142,Mississippi Rd, Tyndall AFB, FL 32403 USA. EM ray.wells@mlg.afr1.af.mil NR 24 TC 5 Z9 5 U1 1 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD APR PY 1999 VL 31 IS 4 BP 315 EP 322 DI 10.1002/(SICI)1097-4601(1999)31:4<315::AID-KIN9>3.0.CO;2-7 PG 8 WC Chemistry, Physical SC Chemistry GA 182UM UT WOS:000079516600009 ER PT J AU Gao, XL Rowlands, RE AF Gao, XL Rowlands, RE TI Analytical solution for the plane strain inclusion problem of an elastic power-law hardening matrix containing an elastic cylindrical inclusion SO INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING LA English DT Article DE elasto-plastic; plane strain; stress/strain analysis; inclusion problems; metal-matrix composites ID MULTIPLE-BOLTED JOINTS; CIRCULAR INCLUSION AB An elasto-plastic analytical solution is presented for the plane strain inclusion problem of an elastic power-law hardening matrix containing an elastic cylindrical inclusion and subjected to equi-biaxial tension. Hencky's deformation theory and von Mises' yield criterion are used. All stress, strain and displacement components are derived in explicit forms in terms of two constant parameters, which are determined from the boundary conditions using a simple iterative procedure. Three specific solutions of practical interest are obtained as limiting cases. Illustrative numerical results are also provided to demonstrate applications of the solution. It is quantitatively shown that the extent of plastic deformation in the matrix is controlled by the ratio of Young's moduli of the inclusion and matrix materials, Poisson's ratio of the inclusion material and the strain-hardening effect of the matrix material, of which the first two factors are dominant. These findings are of practical importance to the design of fiber-filled metal-matrix composites. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Gao, XL (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 11 TC 10 Z9 10 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0308-0161 J9 INT J PRES VES PIP JI Int. J. Pressure Vessels Pip. PD APR PY 1999 VL 76 IS 5 BP 291 EP 297 DI 10.1016/S0308-0161(99)00002-2 PG 7 WC Engineering, Multidisciplinary; Engineering, Mechanical SC Engineering GA 184EU UT WOS:000079598100003 ER PT J AU Niemer-Tucker, MMB Sterk, CC de Wolff-Rouendaal, D Lee, AC Lett, JT Cox, A Spek, KE Davelaar, J Lambooy, AC Mooy, CM Broerse, JJ AF Niemer-Tucker, MMB Sterk, CC de Wolff-Rouendaal, D Lee, AC Lett, JT Cox, A Spek, KE Davelaar, J Lambooy, AC Mooy, CM Broerse, JJ TI Late ophthalmological complications after total body irradiation in non-human primates SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID BONE-MARROW TRANSPLANTATION; RHESUS-MONKEYS; RADIATION RETINOPATHY; CATARACTS; MODEL; CATARACTOGENESIS; DOSIMETRY; PROTONS AB Purpose: To investigate the long-term effects of total body irradiation (TBI) on the incidence and time course of ocular complications. Materials and methods: Rhesus monkeys treated with TBI photon doses up to 8.5 Gy and proton doses up to 7.5 Gy were studied at intervals up to 25 years post-irradiation. They were compared with control groups with a similar age distribution. Cataract formation and ocular fundus lesions were scored according to a standardized protocol. Fluorescein angiography and histopathology was performed in selected animals. Results: Cataract formation occurred after a latent period of 3-5 years. Significant cataract induction was observed for photon-doses of 8 and 8.5 Gy and beyond 20 years after proton irradiation. The severity of the lesions represents significant impairment of vision and would require cataract surgery if similar results occurred in human bone marrow transplant patients. Fluorescein angiography demonstrated a normal pattern of retinal vessels in 13 out of 14 animals (93%) from the irradiated group and in eight out of nine animals (89%) from the control group. No additional lesions apart from age-related degenerative changes could be demonstrated. Histological evaluation revealed no radiation-associated vasculopathy. Conclusions: Radiation alone for doses up to 8.5 Gy of photons does not carry a potential risk for fundus pathology, whereas clinically important cataract induction should be anticipated within 5 years after photon doses of 8.0 and 8.5 Gy and proton doses in excess of 2.5 Gy. C1 Leiden Univ, Med Ctr, Dept Clin Oncol, NL-2300 RC Leiden, Netherlands. Leiden Univ, Med Ctr, Dept Ophthalmol, NL-2300 RC Leiden, Netherlands. Colorado State Univ, Dept Radiol Hlth Sci, Ft Collins, CO 80523 USA. USAF, Armstrong Lab, Occupat & Environm Hlth Directorate, Brooks AFB, TX 78235 USA. Erasmus Univ, Dept Ophthalmopathol, NL-3000 DR Rotterdam, Netherlands. TNO, Ctr Radiat Protect & Dosimetry, NL-2280 HV Rijswijk, Netherlands. RP Niemer-Tucker, MMB (reprint author), Univ Nijmegen St Radboud Hosp, Dept Med Oncol, POB 9101, NL-6500 HB Nijmegen, Netherlands. NR 44 TC 17 Z9 17 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD APR PY 1999 VL 75 IS 4 BP 465 EP 472 DI 10.1080/095530099140393 PG 8 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 186TQ UT WOS:000079745700009 PM 10331852 ER PT J AU Griger, DR Higgs, JB Roane, DW AF Griger, DR Higgs, JB Roane, DW TI Azathioprine hepatotoxicity is uncommon in patients with rheumatic diseases SO JCR-JOURNAL OF CLINICAL RHEUMATOLOGY LA English DT Article DE rheumatoid arthritis; azathioprine; hepatotoxicity ID DOUBLE-BLIND TRIAL; ARTHRITIS; CYCLOSPORINE; METHOTREXATE; TOXICITY AB At present, there is no consensus regarding the utility of liver enzyme monitoring in rheumatology patients undergoing treatment with azathioprine (AZA). To further investigate this issue, we retrospectively reviewed for current or past use of AZA all patient records in our Disease Modifying Antirheumatic Drug (DMARD) clinic from May 1986 through September 1996. Information available from individual DMARD charts included AZA data (dates initiated, dose, indication for changing dose or stopping AZA), co-administered DMARDs, and aspartate aminotransferase (AST) serum values. Ln patients followed in the clinic through February 1994, serum alkaline phosphatase (AP) values additionally were available. Published reports of AZA hepatotoxicity in rheumatoid arthritis (RA) patients were found by a MEDLINE search, supplemented by a manual search of reference Lists. We screened 429 patient records, and all patients who had received AZA at any time during the study period (n = 56) were identified for further review. The mean daily AZA dose was 96 mg (median = 100 mg/day, range = 25-200 mg/day). All of the 56 patients had undergone routine periodic monitoring of serum AST while taking AZA (mean interval = 26 days); 30 of these patients additionally underwent monitoring of serum AP (mean interval = 24 days). Twenty-three (41%) of the patients had at least one episode of an abnormally elevated serum AST and/or AP while taking AZA. Only 1 of these 2 laboratory values was abnormal in 12 patients, The average time from AZA initiation to first appearance of an abnormal AST and/or AP value was 27 days (range = 7-62 days). During observation alone, all abnormal laboratory test results became normalized in 20 of 23 patients (87%) during the study period. There were no interventions in response to an abnormal laboratory value, and no patient experienced an adverse clinical outcome attributable to AZA hepatotoxicity during the 10-year study period. AZA use for rheumatic conditions may be associated with elevations in both the serum AST and/or AP values. Most of these elevations were transient, and none were clinically significant in our patient population. This study supports current American College of Rheumatology guidelines, which do not recommend routine periodic monitoring with liver enzyme tests in RA patients taking AZA. Furthermore, this study suggests that the utility of the baseline liver enzyme test in these patients is not well established. C1 David Grant Med Ctr, Travis AFB, CA USA. Wilford Hall USAF Med Ctr, Int Med Specialty Div, Lackland AFB, TX USA. Uniformed Serv Univ Hlth Sci, Int Med Specialty Div, Bethesda, MD 20814 USA. RP Griger, DR (reprint author), 713 Derry Circle, Vacaville, CA 95688 USA. NR 19 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1076-1608 J9 JCR-J CLIN RHEUMATOL JI JCR-J. Clin. Rheumatol. PD APR PY 1999 VL 5 IS 2 BP 60 EP 63 DI 10.1097/00124743-199904000-00005 PG 4 WC Rheumatology SC Rheumatology GA 193BM UT WOS:000080115600005 PM 19078358 ER PT J AU Power, GJ Karim, MA Ahmed, F AF Power, GJ Karim, MA Ahmed, F TI Velocital information feature for charting spatio-temporal changes in digital image sequences SO JOURNAL OF ELECTRONIC IMAGING LA English DT Article AB This paper introduces a velocital information feature that is extracted for each frame of an image sequence. The feature is based on the optical flow in each frame. A mathematical formulation for the velocital information feature is derived. Charting the feature over a sequence provides a quality metric called velocital information content (VIC). The relationship of VIC to the spatial and temporal information content is shown. VIC offers a different role from traditional transmission-based quality metrics which require two images: the original input image and degraded output image to calculate the quality metric. VIC can detect artifacts from a single image sequence by charting variations from the norm. Therefore, VIC offers a metric for judging the quality of the image frames prior to transmission, without a transmission system or without any knowledge of the higher quality image input The differences between VIC and transmission-oriented quality metrics can provide a different role for VIC in analysis and image sequence processing. Results show that VIC is able to detect gradual and sudden changes in an image sequence. Results are shown for using VIC as a filter on electro-optical infrared image sequences where VIC detects frames suffering from erratic noise. (C) 1999 SPIE and IS&T. [S1017-9909(99)00302-5]. C1 USAF, Target Recognit Branch, AFRLSNAT, Wright Patterson AFB, OH 45433 USA. Univ Tennessee, Dept Elect Engn, Knoxville, TN 37996 USA. Penn State Univ, Behrend Coll, Sch Engn & Engn Technol, Erie, PA 16563 USA. RP Power, GJ (reprint author), USAF, Target Recognit Branch, AFRLSNAT, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 10 TC 5 Z9 5 U1 0 U2 0 PU I S & T - SOC IMAGING SCIENCE TECHNOLOGY PI SPRINGFIELD PA 7003 KILWORTH LANE, SPRINGFIELD, VA 22151 USA SN 1017-9909 J9 J ELECTRON IMAGING JI J. Electron. Imaging PD APR PY 1999 VL 8 IS 2 BP 167 EP 175 DI 10.1117/1.482695 PG 9 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA 280LE UT WOS:000085103600004 ER PT J AU Ling, J Cao, Y Chang, WS AF Ling, J Cao, Y Chang, WS TI Analyses of radially rotating high-temperature heat pipes for turbomachinery applications SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article AB A set of closed-form solutions for the liquid film distributions in the condenser section of a radially rotating miniature heat pipe and for the vapor temperature drop along the heat pipe length are derived. The heat transfer limitations of the heat pipe are analyzed under turbine blade cooling conditions. Analytical results indicate that the condenser heat transfer limitation normally encountered by low-temperature heat pipes no longer exists for the high-temperature rotating heat pipes that are employed for turbine blade cooling. It is found that the heat pipe diameter, radially rotating speed, and operating temperature are very important to the performance of the heat pipe. Heat transfer limitations may be encountered for an increased heat input and rotating speed, or a decreased hydraulic diameter. Based on the extensive analytical evaluations, it is concluded that the radially rotating miniature heat pipe studied in this paper is feasible for turbine blade cooling applications. C1 Florida Int Univ, Dept Mech Engn, Miami, FL 33199 USA. USAF, Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. RP Ling, J (reprint author), Florida Int Univ, Dept Mech Engn, Miami, FL 33199 USA. NR 15 TC 14 Z9 14 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0742-4795 J9 J ENG GAS TURB POWER JI J. Eng. Gas. Turbines Power-Trans. ASME PD APR PY 1999 VL 121 IS 2 BP 306 EP 312 DI 10.1115/1.2817121 PG 7 WC Engineering, Mechanical SC Engineering GA 189BB UT WOS:000079883300018 ER PT J AU Cliver, EW Ling, AG Wise, JE Lanzerotti, LJ AF Cliver, EW Ling, AG Wise, JE Lanzerotti, LJ TI A prediction of geomagnetic activity for solar cycle 23 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CORONAL MASS EJECTIONS; SUNSPOT NUMBER; WIND; AA; DYNAMO; INDEX AB Using a database of 13 solar cycles of geomagnetic aa data, we obtained correlations between cycle averages of geomagnetic activity (and sunspot number) and the numbers of days with disturbance levels above certain aa thresholds. We then used a precursor-type relation to predict an average aa index of 23.1 nT for cycle 23 and inserted this average aa value into the above correlations to forecast the integral size distribution of geomagnetic activity for the new cycle. The predicted size distribution is similar to that observed for cycles 21 and 22 but most closely resembles that of solar cycle 18 (1944-1954), which was slightly smaller than cycles 21 and 22. Our prediction agrees reasonably well with the "climatology-based" forecast made by the intergovernmental panel tasked to predict geomagnetic activity far the coming solar cycle and is significantly different from their "precursor-based" prediction. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. Radex Inc, Bedford, MA 01730 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. RP Cliver, EW (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 13 TC 12 Z9 12 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 1999 VL 104 IS A4 BP 6871 EP 6876 DI 10.1029/1998JA900081 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 182CU UT WOS:000079481600019 ER PT J AU Kennefick, CM AF Kennefick, CM TI Constrained cavitation and fast fracture at metal-ceramic interfaces at elevated temperatures SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID INTERGRANULAR CAVITY GROWTH; POLYCRYSTALLINE ALUMINA; DIFFUSIVE CAVITATION; CREEP; TENSION AB Processes that constrain or promote cavity growth and fast fracture at elevated temperatures are examined. Solutions are given for the stress caused by inhomogeneous deposition of matter in metal-ceramic and alumina grain boundaries and for the tensile stress near the top of a hemispherical pore during pore growth. Velocities of dislocation climb that could promote fast fracture are calculated for elastic stresses acting upon dislocations arising from both a crack tip and interface repulsion. The rates for the atomic diffusive processes and the magnitudes of stresses resulting from them are found to agree well with experimental rate of pore growth, and new data on pore growth and fracture at an aluminum-sapphire interface are presented. C1 USA, Res Lab, Aberdeen Proving Ground, MD 21005 USA. RP Kennefick, CM (reprint author), AFRL, MLBC, 2941 P St,Ste 1,Bldg 654, Wright Patterson AFB, OH 45433 USA. NR 24 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD APR PY 1999 VL 14 IS 4 BP 1306 EP 1315 DI 10.1557/JMR.1999.0178 PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 235PC UT WOS:000082550400024 ER PT J AU Chen, PY Melvin, WL Wicks, MC AF Chen, PY Melvin, WL Wicks, MC TI Screening among multivariate normal data SO JOURNAL OF MULTIVARIATE ANALYSIS LA English DT Article DE hypergeometric function in matrix argument; indifference zone approach; eigenvalue; least favorable configuration; multivariate normal; probability of a correct screening; radar signal processing; ranking and selection; subset selection approach AB This paper considers the problem of screening k multivariate normal populations (secondary data) with respect to a control population (primary data) in terms of covariance structure. A screening procedure, developed based upon statistical ranking and selection theory, is designed to include in the selected subset those populations which have the same (or similar) covariance structure as the control population, and exclude those populations which differ significantly. Formulas for computing the probability of a correct selection and the least favorable configuration are developed. The sample size required to achieve a specific probability requirement is also developed, with results presented in tabular form. This secondary data selection procedure is illustrated via an example with applications to radar signal processing. (C) 1999 Academic Press. C1 Syracuse Univ, Dept Math, Syracuse, NY 13244 USA. Georgia Tech Res Inst, Smyrna, GA USA. USAF, Res Lab, Rome, NY USA. RP Chen, PY (reprint author), Syracuse Univ, Dept Math, Syracuse, NY 13244 USA. NR 16 TC 81 Z9 84 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0047-259X J9 J MULTIVARIATE ANAL JI J. Multivar. Anal. PD APR PY 1999 VL 69 IS 1 BP 10 EP 29 DI 10.1006/jmva.1998.1788 PG 20 WC Statistics & Probability SC Mathematics GA 187CF UT WOS:000079768000002 ER PT J AU Carbone, EG Cigrang, JA Todd, SL Fiedler, ER AF Carbone, EG Cigrang, JA Todd, SL Fiedler, ER TI Predicting outcome of military basic training for individuals referred for psychological evaluation SO JOURNAL OF PERSONALITY ASSESSMENT LA English DT Article AB We examined outcome data for 632 U.S. Air Force personnel who were referred for psychological evaluation during Basic Military Training (BMT) but who were subsequently returned to BMT to determine what proportion graduated. We analyzed motivational, biographical, and psychological testing variables, using logistic regression to develop a model predictive of training outcome. The results demonstrated that a relatively small number of variables could predict outcome with close to 70% accuracy. Level of optimism regarding training, history of physical abuse, and frequency of visits to the trainee health clinic were major contributors to the model. MMPI-2 (Hathaway & McKinley, 1989) Scales D and Sc also remained in the model but added little to its power. The findings are generally consistent with prior research on normal military populations, except that some factors previously linked to adjustment, such as sex and ethnicity, were found to be unrelated to training outcome in this population. C1 Wilford Hall USAF Med Ctr, Behav Anal Serv, Lackland AFB, TX 78236 USA. RP Carbone, EG (reprint author), Wilford Hall USAF Med Ctr, Behav Anal Serv, 59 MDW-MMCNB,2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 25 TC 17 Z9 17 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0022-3891 J9 J PERS ASSESS JI J. Pers. Assess. PD APR PY 1999 VL 72 IS 2 BP 256 EP 265 DI 10.1207/S15327752JP720210 PG 10 WC Psychology, Clinical; Psychology, Social SC Psychology GA 203LZ UT WOS:000080710300010 PM 10410401 ER PT J AU Elston, DM AF Elston, DM TI Zosteriform distribution of acantholytic dyskeratotic epidermal nevus? SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Letter C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. RP Elston, DM (reprint author), Wilford Hall USAF Med Ctr, 2200 Berquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD APR PY 1999 VL 40 IS 4 BP 647 EP 647 PG 1 WC Dermatology SC Dermatology GA 179TA UT WOS:000079344100028 PM 10188696 ER PT J AU Hernandez, J Sabanegh, ES AF Hernandez, J Sabanegh, ES TI Repeat vasectomy reversal after initial failure: Overall results and predictors for success SO JOURNAL OF UROLOGY LA English DT Article; Proceedings Paper CT 93rd Annual Meeting of the American-Urological-Association CY MAY 30-JUN 04, 1998 CL SAN DIEGO, CALIFORNIA SP Amer Urol Assoc DE infertility, male; reanastomoses, vas; surgical procedure, reconstructive ID INTRACYTOPLASMIC SPERM INJECTION; EPIDIDYMAL SPERM; VASOEPIDIDYMOSTOMY; INFERTILITY; VASOVASOSTOMY AB Purpose: We review the treatment outcomes for microsurgical reconstruction following failed vasectomy reversal and identify predictors for success. Materials and Methods: We performed a retrospective review of our experience with microsurgical reconstruction in 41 men who underwent 1 or more prior unsuccessful vasectomy reversal procedures. Of these patients 20 underwent bilateral (16) or unilateral (4) vasoepididymostomy, 11 underwent bilateral (7) or unilateral (4) vasovasostomy and 10 underwent unilateral vasoepididymostomy with contralateral vasovasostomy. Postoperative followup consisted of serial semen analyses and telephone interviews. Results: Patency and pregnancy followup data were available in 33 and 31 patients, respectively. Five couples had ongoing uncorrected female factor infertility problems and were not included in pregnancy rate calculations. Mean obstructive interval was 10.6 years. Overall patency and pregnancy rates were 79 and 31%, respectively. Mean total motile sperm count for patients demonstrating patency at followup was 38.0 million. History of conception with the current partner was predictive of future conception with 4 of 5 nonremarried couples (80%) initiating a pregnancy versus 3 of 18 remarried couples (17%) (p = 0.006). Other factors, including smoking history and obstructive interval, did not correlate with postoperative success. Reconstruction with vasovasostomy on at least 1 side trended toward improved patency (p = 0.17) and pregnancy rates (p = 0.15), although they did not assume statistical significance. Conclusions: Microsurgical reconstruction following failed vasectomy reversal is associated with high patency and moderate pregnancy rates at short-term followup. In our series previous conception with the current partner was predictive of future conception after reconstruction. Urologists performing repeat vasectomy reversal must be familiar with microsurgical techniques, since almost three-quarters of patients will require at least unilateral vasoepididymostomy. C1 Wilford Hall USAF Med Ctr, Dept Urol, San Antonio, TX 78236 USA. RP Hernandez, J (reprint author), Wilford Hall USAF Med Ctr, Dept Urol, San Antonio, TX 78236 USA. NR 16 TC 23 Z9 23 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0022-5347 J9 J UROLOGY JI J. Urol. PD APR PY 1999 VL 161 IS 4 BP 1153 EP 1156 DI 10.1016/S0022-5347(01)61616-1 PG 4 WC Urology & Nephrology SC Urology & Nephrology GA 174BJ UT WOS:000079014000027 PM 10081859 ER PT J AU Bunning, TJ Maher, PT Barnes, W Hood, PJ AF Bunning, TJ Maher, PT Barnes, W Hood, PJ TI Mid-wavelength IR (MWIR) polarizers from glassy cholesteric liquid crystals SO LIQUID CRYSTALS LA English DT Article ID PHASE-BEHAVIOR AB The investigation of glass-forming liquid crystalline materials for mid wave infrared polarization applications is driven by their low melt viscosity and ability to vitrify order, and thus functionality, into films with a wide range of thicknesses. Commercially available polarizers that function in the mid-wave infrared region suffer from poor polarization contrast, high cost, and limited size. In this work, we explore the feasibility of using cyclic siloxane-based liquid crystalline materials with chiral mesogens to form circular polarizers in the midwave infrared spectrum (3-5 mu m) Specifically, we have designed a cholesteric molecular blend to possess the proper helical twisting power to exhibit a selective reflection notch in the 4.0-4.5 mu m region. We have fabricated circular polarizers using shear under a number of processing conditions, and explored their performance as measured by polarization contrast. Processed films with reflection notches at the proper wavelength and near theoretical reflection performance have been prepared. A proper balance between film thickness and cooling rate has led to the demonstration of optically transparent and uniform films on 1 inch diameter substrates. The use of simple alignment layers was demonstrated to yield consistent formation of Grandjean monodomains, by reducing the tendency of the large pitch blends to spontaneously form a fingerprint molecular orientation observed in cells with untreated surfaces. The measured polarization contrast of > 70:1 exceeds the values obtained from state-of-the art commercial polarizers in this wavelength region. C1 MLPJ, AFRL, Wright Patterson AFB, OH 45433 USA. MLBP Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. SW Ohio Council Higher Educ, Dayton, OH 45431 USA. Cornerstone Res Grp Inc, Dayton, OH 45440 USA. RP Bunning, TJ (reprint author), MLPJ, AFRL, Wright Patterson AFB, OH 45433 USA. NR 17 TC 4 Z9 4 U1 1 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0267-8292 J9 LIQ CRYST JI Liq. Cryst. PD APR PY 1999 VL 26 IS 4 BP 557 EP 565 PG 9 WC Chemistry, Multidisciplinary; Crystallography; Materials Science, Multidisciplinary SC Chemistry; Crystallography; Materials Science GA 181QV UT WOS:000079454200011 ER PT J AU Talcott, GW Haddock, CK Klesges, RC Lando, H Fiedler, E AF Talcott, GW Haddock, CK Klesges, RC Lando, H Fiedler, E TI Prevalence and predictors of discharge in United States Air Force Basic Military Training SO MILITARY MEDICINE LA English DT Article ID WEIGHT AB The purpose of the current investigation was to determine the prospective predictors of discharge in a population of individuals entering U.S. Air Force Basic Military Training (BMT). Subjects were 32,144 consecutive individuals entering Air Force BMT. In the first week, subjects filled out a comprehensive lifestyle and behavioral assessment. Over time, a total of 1,999 subjects (6.2%) dropped out of BMT for a variety of reasons, the most common being medical (33.6%), psychiatric (21.3%), legal (20%), and poor performance (13.1%). Overall, discharges by gender were equal, but the reasons for discharge varied by gender. Ethnicity predicted for medical, psychiatric, and legal discharge. Results suggest that women and ethnic minorities are not biased in favor of discharge and that both lifestyle and psychosocial variables are consistent predictors of discharge. Future research could potentially yield other significant predictors of success versus discharge in the U.S. military. C1 Wilford Hall USAF Med Ctr, Dept Psychol, Lackland AFB, TX 78253 USA. RP Talcott, GW (reprint author), Wilford Hall USAF Med Ctr, Dept Psychol, 2200 Bergquist Dr STE 1, Lackland AFB, TX 78253 USA. FU NHLBI NIH HHS [HL-53478] NR 14 TC 32 Z9 32 U1 0 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD APR PY 1999 VL 164 IS 4 BP 269 EP 274 PG 6 WC Medicine, General & Internal SC General & Internal Medicine GA 185JD UT WOS:000079664600008 PM 10226453 ER PT J AU Olivere, JW Cina, SJ AF Olivere, JW Cina, SJ TI The regional medical examiner of the Office of the Armed Forces Medical Examiner: An introduction for the practicing military physician SO MILITARY MEDICINE LA English DT Article C1 Wilford Hall USAF Med Ctr, Dept Pathol, Lackland AFB, TX 78236 USA. RP Olivere, JW (reprint author), Wilford Hall USAF Med Ctr, Dept Pathol, Lackland AFB, TX 78236 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD APR PY 1999 VL 164 IS 4 BP 298 EP 299 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 185JD UT WOS:000079664600014 PM 10226459 ER PT J AU Carter, MA Oxley, ME AF Carter, MA Oxley, ME TI Evaluating the Vapnik-Chervonenkis dimension of artificial neural networks using the Poincare polynomial SO NEURAL NETWORKS LA English DT Article DE artificial neural networks; Vapnik-Chervonenkis dimension; Poincare polynomial; combinatorial geometry; hyperplane arrangements; lattice theory AB The Vapnik-Chervonenkis (V-C) dimension of a set of functions representing a feed-forward, multi-layered, single output artificial neural network (ANN) with hard-limited activation functions can be evaluated using the Poincare polynomial of the implied hyperplane arrangement. This ANN is geometrically a hyperplane arrangement, which is configured to dichotomize a signed set (i.e., a two-class set). As it is known that the cut-intersections of the hyperplane arrangement forms a semi-lattice, the Poincare polynomial can be used to evaluate certain geometric invariants of this semi-lattice, in particular, the cardinality of the resultant chamber set of the arrangements, which is shown to be the V-C dimension. From this theory, we arrive at a stable formula to compute the V-C dimension values. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Inst Technol, Dept Math & Stat, Wright Patterson AFB, OH 45433 USA. Natl Air Intelligence Ctr, Wright Patterson AFB, OH 45433 USA. RP Oxley, ME (reprint author), USAF, Inst Technol, Dept Math & Stat, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 10 TC 8 Z9 9 U1 3 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0893-6080 J9 NEURAL NETWORKS JI Neural Netw. PD APR PY 1999 VL 12 IS 3 BP 403 EP 408 DI 10.1016/S0893-6080(98)00145-2 PG 6 WC Computer Science, Artificial Intelligence SC Computer Science GA 191JY UT WOS:000080020300001 ER PT J AU Shenberger, JS Choate, JA Dixon, PS Helal, K Barth, W AF Shenberger, JS Choate, JA Dixon, PS Helal, K Barth, W TI Pregnancy increases parathyroid hormone related protein (PTHrP) secretion from human uterine smooth muscle cells SO PEDIATRIC RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT PEDIATRIC RESEARCH FOUNDATION, INC PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 USA SN 0031-3998 J9 PEDIATR RES JI Pediatr. Res. PD APR PY 1999 VL 45 IS 4 MA 564 BP 97A EP 97A DI 10.1203/00006450-199904020-00581 PN 2 PG 1 WC Pediatrics SC Pediatrics GA 182AQ UT WOS:000079476700565 ER PT J AU DiGeronimo, RJ Welke, TM Segura-Jones, L Suzuki, Y Seidner, SR AF DiGeronimo, RJ Welke, TM Segura-Jones, L Suzuki, Y Seidner, SR TI Effects of postnatal dexamethasone and exogenous surfactant on surfactant protein B mobilization in preterm rabbits SO PEDIATRIC RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Kyoto Univ, Kyoto 606, Japan. Univ Texas, Hlth Sci Ctr, San Antonio, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT PEDIATRIC RESEARCH FOUNDATION, INC PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 USA SN 0031-3998 J9 PEDIATR RES JI Pediatr. Res. PD APR PY 1999 VL 45 IS 4 MA 1772 BP 301A EP 301A DI 10.1203/00006450-199904020-01789 PN 2 PG 1 WC Pediatrics SC Pediatrics GA 182AQ UT WOS:000079476701773 ER PT J AU Shenberger, JS Dixon, PS AF Shenberger, JS Dixon, PS TI Proliferative and anti-proliferative effects of calcitonin gene-related peptide (CGRP) in bronchial smooth muscle cells: Relationship to cAMP concentrations SO PEDIATRIC RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT PEDIATRIC RESEARCH FOUNDATION, INC PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 USA SN 0031-3998 J9 PEDIATR RES JI Pediatr. Res. PD APR PY 1999 VL 45 IS 4 MA 2094 BP 355A EP 355A DI 10.1203/00006450-199904020-02111 PN 2 PG 1 WC Pediatrics SC Pediatrics GA 182AQ UT WOS:000079476702094 ER PT J AU Shenberger, JS Dixon, PS AF Shenberger, JS Dixon, PS TI Upregulation of p21(WAF1) is not essential for oxygen-induced growth arrest SO PEDIATRIC RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT PEDIATRIC RESEARCH FOUNDATION, INC PI BALTIMORE PA 351 WEST CAMDEN ST, BALTIMORE, MD 21201-2436 USA SN 0031-3998 J9 PEDIATR RES JI Pediatr. Res. PD APR PY 1999 VL 45 IS 4 MA 2095 BP 355A EP 355A DI 10.1203/00006450-199904020-02111 PN 2 PG 1 WC Pediatrics SC Pediatrics GA 182AQ UT WOS:000079476702095 ER PT J AU Ham, BS Hemmer, PR Shahriar, MS AF Ham, BS Hemmer, PR Shahriar, MS TI Efficient phase conjugation via two-photon coherence in an optically dense crystal SO PHYSICAL REVIEW A LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; QUANTUM INTERFERENCE; TRANSITIONS; SODIUM; VAPOR; ATOMS AB We demonstrate efficient phase conjugation in an inhomogeneously broadened rare-earth doped crystal using electromagnetically induced transparency. The observed frequency conversion efficiency of the phase conjugate in energy over a backward pump beam is as high as 10% with similar to 1/4 of maximal Raman coherence. This efficient phase conjugation has potential applications of nonlinear optical processes such as frequency up-conversion and Raman excited spin-echo optical memory. [S1050-2947(99)50704-X]. C1 MIT, Elect Res Lab, Cambridge, MA 02139 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Ham, BS (reprint author), MIT, Elect Res Lab, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Shahriar, Selim/B-7270-2009 NR 20 TC 17 Z9 17 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1999 VL 59 IS 4 BP R2583 EP R2586 DI 10.1103/PhysRevA.59.R2583 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 184JT UT WOS:000079609100012 ER PT J AU Naboulsi, SK Bechtel, SE AF Naboulsi, SK Bechtel, SE TI Bicomponent Newtonian filaments SO PHYSICS OF FLUIDS LA English DT Article ID PROFILE DEVELOPMENT; FIBER; JETS; MECHANICS; STABILITY; LIQUID; FLOW AB A model is introduced which captures the mechanical behavior of slender bicomponent filaments. The model is deduced from the three-dimensional free surface boundary value problem through integration over the filament cross section, and applied to core and sheath fluids which are Newtonian with a bonded interface. Through examples simulating filament manufacturing processes, we investigate different regimes of bicomponent filament behavior, examining the interplay of core and sheath viscosities and densities, and surface and interfacial tensions (which are found to have special importance). We focus on features which are special to bicomponent filaments, namely the traction at the core/sheath interface, the partition of the axial force in the filament between core and sheath, and dependence on sheath-to-core ratios of material properties. (C) 1999 American Institute of Physics. [S1070-6631(99)02004-8]. C1 USAF, Dept Aeronaut & Astronaut, Inst Technol, Wright Patterson AFB, OH 45433 USA. Ohio State Univ, Dept Aerosp Engn Appl Mech & Aviat, Columbus, OH 43210 USA. RP Naboulsi, SK (reprint author), USAF, Dept Aeronaut & Astronaut, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 35 TC 5 Z9 5 U1 2 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD APR PY 1999 VL 11 IS 4 BP 807 EP 820 DI 10.1063/1.869953 PG 14 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 178YZ UT WOS:000079297900007 ER PT J AU Adkins, JA AF Adkins, JA TI Promoting organizational health: The evolving practice of occupational health psychology SO PROFESSIONAL PSYCHOLOGY-RESEARCH AND PRACTICE LA English DT Article ID STRESS AB Occupational health psychology (OHP) is a rapidly expanding interdisciplinary field. This article attempts to describe a framework of organizing principles and core competencies associated with OHP practice. These concepts are illustrated in a case study of an organizational health center (OHC) implemented within a large industrial complex. The OHC was designed to optimize both organizational health and individual well-being by applying behavioral science principles to a workplace setting producing both quantitative and qualitative benefits for the organization. The OHC program components, enveloped in a preventive stress management context, provide examples of the variety of opportunities in OHP with hopes of stimulating your own ideas for practice. Continuing to build and refine both the guiding theory and applications of OHP practice will yield benefits for organizational clients, practitioners, and the profession. C1 Harvard Univ, Sch Med, Dept Hlth Care Policy, Boston, MA 02115 USA. USAF, Washington, DC 20330 USA. RP Adkins, JA (reprint author), Harvard Univ, Sch Med, Dept Hlth Care Policy, 180 Longwood Ave, Boston, MA 02115 USA. NR 36 TC 15 Z9 17 U1 0 U2 2 PU AMER PSYCHOLOGICAL ASSOC PI WASHINGTON PA 750 FIRST ST NE, WASHINGTON, DC 20002-4242 USA SN 0735-7028 J9 PROF PSYCHOL-RES PR JI Prof. Psychol.-Res. Pract. PD APR PY 1999 VL 30 IS 2 BP 129 EP 137 DI 10.1037//0735-7028.30.2.129 PG 9 WC Psychology, Multidisciplinary SC Psychology GA 187BF UT WOS:000079765600004 ER PT J AU Tam, S Fajardo, ME AF Tam, S Fajardo, ME TI Ortho/para hydrogen converter for rapid deposition matrix isolation spectroscopy SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID HIGH-RESOLUTION SPECTROSCOPY; THERMAL-CONDUCTIVITY; SOLID PARAHYDROGEN; ABSOLUTE DETERMINATION; NOBLE-GASES; LASER; TRANSITIONS; PHOTOLYSIS; DENSITY; CRYSTAL AB We describe the construction and operation of a catalyst-bed type device for precooling and equilibrating the ortho/para composition of a hydrogen gas flow. We use this device to vapor deposit millimeters thick cryogenic parahydrogen ( pH(2)) solids which are remarkably transparent [M. E. Fajardo and S. Tam, J. Chem. Phys. 108, 4237 (1998)]. Infrared absorption spectra of solids deposited at pH(2) flow rates up to 290 mmol/h (solid thickness growth rates up to 75 mu m/min indicate a residual orthohydrogen (oH(2)) content of less than 0.01%. Gas phase thermal conductivity measurements indicate a residual oH(2) content of 0((+5)(-0))% for flow rates up to 1.9 mol/h. These pH(2) solids can be doped readily by simple codeposition of various impurities produced by any of the numerous dopant sources developed in previous matrix isolation spectroscopy (MIS) studies. The long achievable path lengths, and the desirable properties of pH(2) as a matrix host, will enable significant new fundamental and practical applications for MIS. [S0034-6748(99)00404-9]. C1 USAF, Res Lab, Propuls Directorate, AFRL PRSP, Edwards AFB, CA 93524 USA. RP Tam, S (reprint author), USAF, Res Lab, Propuls Directorate, AFRL PRSP, Bldg 8451, Edwards AFB, CA 93524 USA. NR 44 TC 82 Z9 82 U1 3 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD APR PY 1999 VL 70 IS 4 BP 1926 EP 1932 DI 10.1063/1.1149734 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 184QM UT WOS:000079624500003 ER PT J AU Method, MW Brost, BC AF Method, MW Brost, BC TI Management of cervical cancer in pregnancy SO SEMINARS IN SURGICAL ONCOLOGY LA English DT Review DE cervix neoplasms; carcinoma in situ; squamous cell carcinoma; incidence; diagnosis; vaginal smears; colposcopy; biopsy; conization; risk factors; time factors; age factors; gestational age; fetal death; delivery; hemorrhage; surgical blood loss; blood transfusions; neoplasm staging; hysterectomy; radiotherapy; neoplastic pregnancy complications; survival rate; radiation dosage; lymph node excision; combined modality therapy; episiotomy; local neoplasm recurrence; brachytherapy; postoperative complications ID RADICAL HYSTERECTOMY; EPISIOTOMY SITE; COMPLICATING PREGNANCY; INCISIONAL RECURRENCE; SURGICAL-MANAGEMENT; VAGINAL DELIVERY; UTERINE CERVIX; PLANNED DELAY; CARCINOMA; FETAL AB Carcinoma of the cervix is the most common gynecologic cancer found during pregnancy. Management and treatment of this condition depend on cancer stage, estimated gestational age, and ethical, religious, and personal desires. Review of the medical literature in English from 1965 to 1998 is presented with recommendations for management. Semin. Surg. Oncol. 16:251-260, 1999. (C) 1999 Wiley-Liss, Inc. C1 Uniformed Serv Univ Hlth Sci, Div Gynecol Oncol, Keesler AFB, MS 39534 USA. RP Method, MW (reprint author), Uniformed Serv Univ Hlth Sci, Div Gynecol Oncol, 81 MSGS SGCG,301 Fisher St,Suite 3A214, Keesler AFB, MS 39534 USA. EM method.michael@keesler.af.mil OI Brost, Brian/0000-0002-4903-4186 NR 57 TC 20 Z9 22 U1 0 U2 1 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 8756-0437 J9 SEMIN SURG ONCOL JI Semin. Surg. Oncol. PD APR-MAY PY 1999 VL 16 IS 3 BP 251 EP 260 DI 10.1002/(SICI)1098-2388(199904/05)16:3<251::AID-SSU11>3.0.CO;2-4 PG 10 WC Oncology; Surgery SC Oncology; Surgery GA 184LN UT WOS:000079613800011 PM 10225305 ER PT J AU Smith, RC Levine, J Dalrymple, NC Barish, M Rosenfield, AT AF Smith, RC Levine, J Dalrymple, NC Barish, M Rosenfield, AT TI Acute flank pain: A modern approach to diagnosis and management SO SEMINARS IN ULTRASOUND CT AND MRI LA English DT Review ID UNENHANCED HELICAL CT; TISSUE RIM SIGN; URETERAL CALCULI; EXCRETORY UROGRAPHY; ACUTE APPENDICITIS; SPIRAL CT; UROLOGICAL MANIFESTATIONS; PERIRENAL COBWEBS; OBSTRUCTION; ULTRASOUND C1 Yale Univ, Sch Med, New Haven, CT 06520 USA. Boston Univ, Med Ctr, Boston, MA USA. USAF, Wilford Hall USAF Med Ctr, San Antonio, TX USA. RP Smith, RC (reprint author), Yale Univ, Sch Med, 333 Cedar St,Room MRC147, New Haven, CT 06520 USA. NR 101 TC 28 Z9 28 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0887-2171 J9 SEMIN ULTRASOUND CT JI Semin. Ultrasound CT MRI PD APR PY 1999 VL 20 IS 2 BP 108 EP 135 DI 10.1016/S0887-2171(99)90042-2 PG 28 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 187AW UT WOS:000079764600007 PM 10222519 ER PT J AU Sanders, TG Ptaszek, AJ Morrison, WB AF Sanders, TG Ptaszek, AJ Morrison, WB TI Fracture of the lateral process of the talus: appearance at MR imaging and clinical significance SO SKELETAL RADIOLOGY LA English DT Article DE MRI; fracture; talus, lateral process; ankle; snowboarding ID INJURED ANKLE LIGAMENTS; NORMAL ANATOMY; SINUS-TARSI AB The case of a 59-year-old man with chronic lateral ankle pain following an inversion injury is presented. MR imaging performed to evaluate for soft tissue injury revealed an unsuspected fracture of the lateral process of the talus. The patient underwent surgical exploration of the fracture with debridement of adjacent loose bodies and is currently undergoing aggressive physical rehabilitation. C1 USAF, Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. USAF, Med Ctr, Dept Orthopaed Surg, Foot & Ankle Serv, Lackland AFB, TX 78236 USA. RP Sanders, TG (reprint author), USAF, Med Ctr, Dept Radiol, Wilford Hall,759th MDTS MTRD,2200 Bergquist Dr,ST, Lackland AFB, TX 78236 USA. NR 21 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0364-2348 J9 SKELETAL RADIOL JI Skeletal Radiol. PD APR PY 1999 VL 28 IS 4 BP 236 EP 239 PG 4 WC Orthopedics; Radiology, Nuclear Medicine & Medical Imaging SC Orthopedics; Radiology, Nuclear Medicine & Medical Imaging GA 202NM UT WOS:000080659000011 PM 10384997 ER PT J AU Hedrick, A AF Hedrick, A TI Soccer-specific conditioning SO STRENGTH AND CONDITIONING JOURNAL LA English DT Article DE soccer; conditioning program; specific demands C1 USAF Acad, Washington, DC 20330 USA. RP Hedrick, A (reprint author), USAF Acad, Washington, DC 20330 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU NATL STRENGTH & CONDITIONING ASSOC PI COLORADO SPRINGS PA 1955 N UNION BLVD, COLORADO SPRINGS, CO 80909 USA SN 1073-6840 J9 STRENGTH COND J JI Strength Cond. J. PD APR PY 1999 VL 21 IS 2 BP 17 EP 21 PG 5 WC Sport Sciences SC Sport Sciences GA 197FG UT WOS:000080353900006 ER PT J AU Childs, JD AF Childs, JD TI The impact of the valsalva maneuver during resistance exercise SO STRENGTH AND CONDITIONING JOURNAL LA English DT Editorial Material C1 Davis Monthan AFB, Tucson, AZ USA. RP Childs, JD (reprint author), Davis Monthan AFB, Tucson, AZ USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU NATL STRENGTH & CONDITIONING ASSOC PI COLORADO SPRINGS PA 1955 N UNION BLVD, COLORADO SPRINGS, CO 80909 USA SN 1073-6840 J9 STRENGTH COND J JI Strength Cond. J. PD APR PY 1999 VL 21 IS 2 BP 54 EP 55 PG 2 WC Sport Sciences SC Sport Sciences GA 197FG UT WOS:000080353900017 ER PT J AU Khot, NS Kolonay, RM Eastep, FE AF Khot, NS Kolonay, RM Eastep, FE TI Composite wing optimization for enhancement of the rolling maneuver in subsonic flow SO STRUCTURAL OPTIMIZATION LA English DT Article AB This paper is concerned with designing an optimum composite wing structure with enhanced roll maneuver capability at high dynamic pressures using a control system to retwist and recamber the wing. Antisymmetric twist and camber distribution on a composite flexible wing, weight optimized with constraints on strength and aileron efficiencies also satisfying flutter requirements, were determined to counter act the detrimental twisting moment of the aileron at high dynamic pressure. The retwisting and recambering of the wing is achieved by providing control forces obtained from a technique referred to as "Fictitious Control Surfaces" (FCS). Two different optimally designed wings with unacceptable roll performance were selected for roll performance improvement investigation. The control energy necessary to retwist the wing to improve the unacceptable roll performance for subsonic design condition was calculated to provide the structural designer an alternative, to the traditional increase of stiffness to satisfy roll performance. C1 USAF, Res Lab, Air Vehicles Directorate, VASD,AFRL,Flight Dynam Directorate,WL FIBD,WPAFB, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Dept Mech & Aerosp Engn, Dayton, OH 45469 USA. RP Khot, NS (reprint author), USAF, Res Lab, Air Vehicles Directorate, VASD,AFRL,Flight Dynam Directorate,WL FIBD,WPAFB, Wright Patterson AFB, OH 45433 USA. NR 9 TC 1 Z9 1 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0934-4373 J9 STRUCT OPTIMIZATION JI Struct. Optim. PD APR PY 1999 VL 17 IS 2-3 BP 95 EP 103 PG 9 WC Computer Science, Interdisciplinary Applications; Engineering, Multidisciplinary; Mechanics SC Computer Science; Engineering; Mechanics GA 194KM UT WOS:000080191600002 ER PT J AU Solomon, JS Petry, L Tomich, DH AF Solomon, JS Petry, L Tomich, DH TI Optimizing GaSb(111) and GaSb(001) surfaces for epitaxial film growth SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 14th International Vacuum Congress/10th International Conference on Solid Surfaces/5th International Conference on Nanometre-Scale Science and Technology/10th International Conference on Quantitative Surface Analysis CY AUG 31-SEP 04, 1998 CL BIRMINGHAM, ENGLAND SP British Vacuum Council, Inst Phys, Int Union Vacuum Sci Tech & Applicat DE GaSb(111); GaSb(001); epitaxial film growth AB Oxides were grown on acid etched ((1) over bar (1) over bar (1) over bar) and GaSb(001) by UV-ozone oxidation. The in-situ thermal desorption of the oxide layers was used to set the true substrate temperature for epitaxial film growth. Oxide desorption was monitored by RHEED and the desorption process was used to set the substrate temperature prior to epitaxial film growth. GaSb wafers were acid etched prior to UV-ozone oxidation to remove native oxides. Auger electron spectroscopy and X-ray photoelectron spectroscopy were used to characterize the surface chemistry resulting from the treatments. Atomic force microscopy (AFM) was used to characterize the surface morphology of the treated wafers. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. MLBM, Air Force Res Lab, Wright Patterson AFB, OH 45433 USA. RP Solomon, JS (reprint author), Univ Dayton, Res Inst, Dayton, OH 45469 USA. EM solomojs@ml.wpafb.af.mil NR 8 TC 3 Z9 3 U1 1 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD APR PY 1999 VL 343 SI SI BP 500 EP 503 DI 10.1016/S0040-6090(98)01704-0 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 210KC UT WOS:000081103100129 ER PT J AU Jepson, GW McDougal, JN AF Jepson, GW McDougal, JN TI Predicting vehicle effects on the dermal absorption of halogenated methanes using physiologically based modeling SO TOXICOLOGICAL SCIENCES LA English DT Article DE halogenated carbons; polar and non-polar vehicles; dermal exposure; permeability coefficients; rat ID PERCUTANEOUS-ABSORPTION; HUMAN-SKIN; COSMETIC VEHICLES; STRATUM-CORNEUM; IN-VITRO; PENETRATION; CHEMICALS; DELIVERY; LINDANE; LIQUIDS AB Occupational and environmental settings present opportunities for humans to come into contact with a variety of chemicals via the dermal route. The chemicals contacting the skin are likely to be diluted with a vehicle or present as a component of a mixture. In order to support risk assessment activities, we evaluated the vehicle effects on dermal penetration of two halogenated hydrocarbons, dibromomethane (DBM) and bromochloromethane (BCM). In vivo exposures to 15 combinations of of these in water, mineral oil, and corn oil vehicles were conducted, and blood was sampled for dibromomethane and bromochloromethane during the exposure at 0.5, 1, 2, 4, 8, 12, and 24 h. A physiologically based pharmacokinetic (PBPK) model was used to estimate the total amounts of dibromomethane or bromochloromethane that were absorbed during the exposure, and the dermal permeability coefficients were determined. While the permeability coefficients for dibromomethane and bromochloromethane were approximately 73- and 40-fold higher, respectively, in the water vehicle than in the corn oil, the permeability coefficient, when normalized for the skin:vehicle matrix partition coefficient, varied by less than a factor of 2. The permeability in an aqueous vehicle was then successfully used to predict the permeability coefficient for dibromomethane in a nonpolar vehicle, peanut oil. C1 USAF, Res Lab, Human Effectiveness Directorate, AFRL HEST, Wright Patterson AFB, OH 45433 USA. RP Jepson, GW (reprint author), Dupont Co, Haskell Labs, H1-1313,POB 50, Newark, DE 19714 USA. NR 21 TC 13 Z9 15 U1 0 U2 2 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1096-6080 J9 TOXICOL SCI JI Toxicol. Sci. PD APR PY 1999 VL 48 IS 2 BP 180 EP 188 DI 10.1093/toxsci/48.2.180 PG 9 WC Toxicology SC Toxicology GA 251PW UT WOS:000083454900004 PM 10353309 ER PT J AU DelRaso, NJ Frazier, JM AF DelRaso, NJ Frazier, JM TI Effect of culture conditions prior to exposure on cadmium cytotoxicity in primary rat hepatocytes SO TOXICOLOGY METHODS LA English DT Article DE cadmium; culture; EC50; hepatocytes; in vitro ID METALLOTHIONEIN EXPRESSION; MONOLAYER-CULTURE; CELLS; GLUTATHIONE; TOXICITY; HEPATOTOXICITY; METALS; GROWTH; ASSAY AB Primary rat hepatocytes are a useful research tool for direct investigation of hepatotoxic effects of chemicals or drugs at the cellular level. USEPA's reevaluation of current human health risk assessment models for the toxic metal cadmium has identified a need for the development of new models that include in vitro toxicity and kinetic data. The EC50 for cadmium obtained in rat hepatocyte cultures in 96-well plates (EC50 [96]= 3.2 +/- 0.8 mu M) was found to be significantly different from that obtained in 6-well cultures (EC50 [6] = 14.8 +/- 0.7 mu M). When medium depth in 96-well plates was adjusted to reflect the same depth as that in 6-well plates prior to, during, and following cadmium exposure, an EC50 was observed that was similar to that obtained in 6-well plates (EC50 [96*]= 13.2 +/- 0.9 mu M). Hepatocytes incubated in 96-well plates with various depths of culture medium from 1 mm (34 mu L/well) to 6 mm (200 mu L/well), exhibited a significant decrease in viability and attached cell protein with greater medium depths. Assessment of various biochemical markers of hepatic function indicated that hepatocytes cultured at 2-mm medium depths were similar to those in vivo. Metal analysis indicated that the amount of cadmium entering hepatocytes was independent of treatment. Thus, differences in toxicity were not a result of differences in cadmium uptake. This study indicated that in vitro test systems should be optimized and validated prior to use in mechanistic and kinetic studies, if they are to be considered by regulatory agencies. C1 HEST, AFRL, Human Effect Directorate, Operat Toxicol Branch, Wright Patterson AFB, OH 45433 USA. RP DelRaso, NJ (reprint author), HEST, AFRL, Human Effect Directorate, Operat Toxicol Branch, 2856 G St, Wright Patterson AFB, OH 45433 USA. NR 32 TC 10 Z9 10 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 1051-7235 J9 TOXICOL METHOD JI Toxicol. Method. PD APR-JUN PY 1999 VL 9 IS 2 BP 97 EP 114 PG 18 WC Toxicology SC Toxicology GA 196PQ UT WOS:000080317100005 ER PT J AU Rice, R AF Rice, R TI Bombing Auschwitz: US 15th Air Force and the military aspects of a possible attack SO WAR IN HISTORY LA English DT Article C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Rice, R (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU ARNOLD, HODDER HEADLINE PLC PI LONDON PA 338 EUSTON ROAD, LONDON NW1 3BH, ENGLAND SN 0968-3445 J9 WAR HIST JI War Hist. PD APR PY 1999 VL 6 IS 2 BP 205 EP 229 PG 25 WC History; International Relations SC History; International Relations GA 184GB UT WOS:000079601300004 ER PT J AU Miyoshi, K Pohlchuck, B Street, KW Zabinski, JS Sanders, JH Voevodin, AA Wu, RLC AF Miyoshi, K Pohlchuck, B Street, KW Zabinski, JS Sanders, JH Voevodin, AA Wu, RLC TI Sliding wear and fretting wear of diamondlike carbon-based, functionally graded nanocomposite coatings SO WEAR LA English DT Article; Proceedings Paper CT 12th International Conference on Wear of Materials CY APR 25-29, 1999 CL ATLANTA, GA DE sliding wear; fretting wear; diamondlike carbon coating ID FILMS AB Improving the tribological functionality of diamondlike carbon (DLC) films-developing good wear resistance, low friction, and high load-carrying capacity-was the aim of this investigation. Nanocomposite coatings consisting of an amorphous DLC (a-DLC) top layer and a functionally graded titanium-titanium carbide-diamondlike carbon (Ti-TixCy-DLC) underlayer were produced on AISI 440C stainless steel substrates by the hybrid technique of magnetron sputtering and pulsed-laser deposition. The resultant DLC films were characterized by Raman spectroscopy, scanning electron microscopy, and surface profilometry. Two types of wear experiment were conducted in this investigation: sliding friction experiments and fretting wear experiments. Unidirectional ball-on-disk sliding friction experiments were conducted to examine the wear behavior of an a-DLC/Ti-TixCy-DLC-coated AISI 440C stainless steel disk in sliding contact with a 6-mm diameter AISI 440C stainless steel ball in ultrahigh vacuum, in dry nitrogen, and in humid air. Although the wear rates for both the coating and ball were low in all three environments, the humid air and dry nitrogen caused mild wear with burnishing in the a-DLC top layer, and the ultrahigh vacuum caused relatively severe wear with brittle fracture in both the a-DLC top layer and the Ti-TixCy-DLC underlayer. For reference, amorphous hydrogenated carbon (H-DLC) films produced on a-DLC/Ti-TixCy-DLC nanocomposite coatings by using an ion beam were also examined in the same manner. The H-DLC films markedly reduced friction even in ultrahigh vacuum without sacrificing wear resistibility. The H-DLC films behaved much like the a-DLC/Ti-TixCy-DLC nanocomposite coating in dry nitrogen and humid air, presenting low friction and low wear. Fretting wear experiments were conducted in humid air (approximately 50% relative humidity) at a frequency of 80 Hz and an amplitude of 75 mu m on an a-DLC/Ti-TixCy-DLC-coated AISI 440C disk and on a titanium-6 wt.% aluminum-4, wt.% vanadium (Ti-6Al-4V) flat, both in contact with a 9.4-mm diameter, hemispherical Ti-6Al-4V pin. The resistance to fretting wear and damage of the a-DLC/Ti-6Al-4V materials pair was superior to that of the Ti-6Al-4V/Ti-6Al-4V materials pair. (C) 1999 Published by Elsevier Science S.A. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. K Syst, Beavercreek, OH 45432 USA. RP NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. EM miyoshi@lerc.nasa.gov RI Voevodin, Andrey/I-6684-2013 NR 18 TC 59 Z9 65 U1 3 U2 27 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0043-1648 EI 1873-2577 J9 WEAR JI Wear PD APR PY 1999 VL 225 BP 65 EP 73 DI 10.1016/S0043-1648(98)00349-4 PN 1 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 190EM UT WOS:000079949200010 ER PT J AU Degnan, JH Alme, ML Austin, BS Beason, JD Coffey, SK Gale, DG Graham, JD Havranek, JJ Hussey, TW Kiuttu, GF Kreh, BB Lehr, FM Lewis, RA Lileikis, DE Morgan, D Outten, CA Peterkin, RE Platts, D Roderick, NF Ruden, EL Shumlak, U Smith, GA Sommars, W Turchi, PJ AF Degnan, JH Alme, ML Austin, BS Beason, JD Coffey, SK Gale, DG Graham, JD Havranek, JJ Hussey, TW Kiuttu, GF Kreh, BB Lehr, FM Lewis, RA Lileikis, DE Morgan, D Outten, CA Peterkin, RE Platts, D Roderick, NF Ruden, EL Shumlak, U Smith, GA Sommars, W Turchi, PJ TI Compression of plasma to megabar range using imploding liner SO PHYSICAL REVIEW LETTERS LA English DT Article ID WORKING FLUIDS; IMPLOSIONS; FUSION AB Axial current discharges were used to implode spherical aluminum shells with thickness tapered to match the external magnetic pressure. These implosions were used to compress hydrogen plasmas with an initial pressure >100 bar and an initial temperature >1 eV. The implosion and compressed plasma effect on a central target were observed radiographically. The target's radius vs time indicates that the plasma pressure reaches similar to 1 Mbar prior to liner-target contact. [S0031-9007(99)08774-8]. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Degnan, JH (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 19 TC 31 Z9 31 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 29 PY 1999 VL 82 IS 13 BP 2681 EP 2684 DI 10.1103/PhysRevLett.82.2681 PG 4 WC Physics, Multidisciplinary SC Physics GA 179UY UT WOS:000079348900015 ER PT J AU Voevodin, AA O'Neill, JP Zabinski, JS AF Voevodin, AA O'Neill, JP Zabinski, JS TI Tribological performance and tribochemistry of nanocrystalline WC/amorphous diamond-like carbon composites SO THIN SOLID FILMS LA English DT Article DE tungsten carbide; diamond-like carbon; composites; hard coating; tribology ID PULSED-LASER DEPOSITION; TUNGSTEN CARBIDE; COATINGS; FILMS; WEAR; SURFACES; LAYERS; STEEL AB The tribological performance and tribochemistry of vacuum deposited nanocrystalline WC/amorphous diamond-like carbon (DLC) composite coatings were investigated. Coating chemistry was varied by regulation of carbon content between 30 and 90 at.%. Deposition temperature was used to adjust the degree of beta-WC crystallinity from near amorphous with 1-3 nm sized grains to nanocrystalline with 5-10 nm sized grains, which were embedded in unhydrogenated DLC matrix. The microstructure critically influenced both the hardness and tribological properties of WC/DLC composites. Coatings with poorly crystallized WC were softer (15 Cpa) and exhibited lower friction and higher wear rates in comparison to harder (26 Cpa) composites with larger WC nanocrystals. The hardness of WC/DLC composites was at least twice as high as the hardness of metal doped DLC coatings reported in the literature. Micro Raman and X-ray photoelectron analysis was performed on transfer films formed on the surface of steel balls in sliding against WC/DLC composites in humid air and dry nitrogen, which found both oxides and graphite carbon, providing self-lubrication. The high hardness and self-lubricating properties of WC composites resulted in low wear rates and friction coefficients of about 0.2. Relationships among coating chemistry, structure, hardness, friction, wear rates, as well as, tribofilm composition and structure are discussed. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Wright Patterson Air Force Base, Air Force Res Lab, Mat & Mfg Directorate, MLBT, Wright Patterson AFB, OH 45433 USA. RP Voevodin, AA (reprint author), Wright Patterson Air Force Base, Air Force Res Lab, Mat & Mfg Directorate, MLBT, Wright Patterson AFB, OH 45433 USA. EM voevodaa@afrl.af.mil RI Voevodin, Andrey/I-6684-2013 NR 39 TC 102 Z9 108 U1 5 U2 43 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD MAR 26 PY 1999 VL 342 IS 1-2 BP 194 EP 200 DI 10.1016/S0040-6090(98)01456-4 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 190TR UT WOS:000079981500032 ER PT J AU Presilla-Marquez, JD Carrick, PG Larson, CW AF Presilla-Marquez, JD Carrick, PG Larson, CW TI Vibrational spectra of linear BC3 and linear B2C2 in argon at 10 K SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT 52nd Ohio State University International Symposium on Molecular Spectroscopy CY JUN 16-20, 1997 CL COLUMBUS, OHIO SP Ohio State Univ ID INFRARED-SPECTRA; SPECTROSCOPY; ATOMS; MATRICES; AR AB The vibrational spectra of linear BC3 and linear B2C2 in an argon matrix at 10 K have been observed for the first time by Fourier transform infrared spectroscopy. Mixtures of boron and carbon powders were vaporized in a resistively heated (similar to 3000 K) oven. BC3 was produced during codeposition of the vapors with argon onto a CsI substrate maintained at 10 K; B2C2 was observed only after annealing the matrices. Frequencies measured at 2002.1 and 1512.5 cm(-1) have been assigned to the nu(1)(sigma) and nu(2)(sigma) B-C stretching fundamentals of linear BC3 and a frequency measured at 955.0 cm(-1) has been assigned to the nu(3)(sigma(u)) stretching fundamental of linear symmetric BC2B. These assignments are based on FTIR measurements of the majority of the BC3 and B2C2 isotopomer frequencies and are consistent with the results from Rittby's collaborative ab initio study. (C) 1999 American Institute of Physics. [S0021-9606(99)00312-8]. C1 Schafer Corp, Calabasas, CA 91302 USA. USAF, Res Lab, Propuls Sci Div, Edwards AFB, CA 93524 USA. RP Presilla-Marquez, JD (reprint author), Schafer Corp, 26565 W Agoura Rd,Suite 202, Calabasas, CA 91302 USA. NR 14 TC 28 Z9 28 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 22 PY 1999 VL 110 IS 12 BP 5702 EP 5709 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 176VK UT WOS:000079172400026 ER PT J AU Look, DC Hemsky, JW Sizelove, JR AF Look, DC Hemsky, JW Sizelove, JR TI Residual native shallow donor in ZnO SO PHYSICAL REVIEW LETTERS LA English DT Article ID DEFECTS; GAAS AB High-energy electron irradiation in ZnO produces shallow donors at about E-C - 30 meV. Because the production rate is much higher for Zn-face (0001) than O-face (000 (1) over bar) irradiation, the donor is identified as a Zn-sublattice defect, most likely the interstitial Zn-I or a Zn-I-related complex. The donor energy is quite close to that of the unirradiated sample, and of other samples discussed in the literature, strongly suggesting that Zn-I (and not V-o) is the dominant native shallow donor in ZnO. An exceptionally high displacement threshold energy (similar to 1.6 MeV) is quantitatively explained in terms of a multiple-displacement model. [S0031-9007(99)08717-7]. C1 Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Look, DC (reprint author), Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. NR 22 TC 824 Z9 856 U1 10 U2 116 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 22 PY 1999 VL 82 IS 12 BP 2552 EP 2555 DI 10.1103/PhysRevLett.82.2552 PG 4 WC Physics, Multidisciplinary SC Physics GA 178HH UT WOS:000079259800033 ER PT J AU Belfield, KD Reinhardt, BA Brott, LL Clarson, SJ Najjar, O Pius, SM Van Stryland, EW Negres, R AF Belfield, KD Reinhardt, BA Brott, LL Clarson, SJ Najjar, O Pius, SM Van Stryland, EW Negres, R TI Synthesis & characterization of new two-photon absorbing polymers. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Cent Florida, Dept Chem, Orlando, FL 32816 USA. Univ Cent Florida, Dept Mech Mat & Aerosp Engn, Orlando, FL 32816 USA. Univ Cent Florida, Sch Opt, Orlando, FL 32816 USA. USAF, Res Lab, Polymer Branch, WL MLBP Mat Directorate, Wright Patterson AFB, OH 45433 USA. Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45221 USA. Univ Detroit Mercy, Dept Chem, Detroit, MI 48219 USA. RI Belfield, Kevin/D-4765-2009 OI Belfield, Kevin/0000-0002-7339-2813 NR 0 TC 1 Z9 2 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 085-POLY BP U540 EP U540 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JP UT WOS:000079148201668 ER PT J AU Clewell, RA Serve, PM Tsui, DT Mattie, D AF Clewell, RA Serve, PM Tsui, DT Mattie, D TI Electrospray mass spectrometric determination of perchlorate in drinking water. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Wright State Univ, Dept Chem, Dayton, OH 45435 USA. AFRL, HEST, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 099-ANYL BP U128 EP U128 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148100321 ER PT J AU Day, PN Nguyen, KA AF Day, PN Nguyen, KA TI Modeling solvent effects on optical limiting materials. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 MLPJ, AFRL, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 082-COMP BP U665 EP U665 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148102057 ER PT J AU Eastwood, D Shaw, JJ Ritchard, NT AF Eastwood, D Shaw, JJ Ritchard, NT TI Dayton Section Women Chemist Committee - Changing the face of chemistry. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Inst Technol, Dept Energy Phys, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 137-IEC BP U905 EP U906 PN 1 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148102836 ER PT J AU Haddad, TS Stapleton, R Jeon, HG Mather, PT Lichtenhan, JD Phillips, S AF Haddad, TS Stapleton, R Jeon, HG Mather, PT Lichtenhan, JD Phillips, S TI Nanostructured hybrid organic/inorganic materials. Silsesquioxane modified plastics. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Raytheon Corp, Edwards AFB, CA 93524 USA. USAF, Res Lab, Edwards AFB, CA 93524 USA. NR 0 TC 1 Z9 1 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 246-POLY BP U608 EP U608 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JP UT WOS:000079148201828 ER PT J AU Layo, FB Castle, PJ Wilkes, JS AF Layo, FB Castle, PJ Wilkes, JS TI Extraction of polymer materials by room temperature molten salts. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 582-CHED BP U474 EP U474 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148101426 ER PT J AU Nguyen, KA Day, PN Pachter, R AF Nguyen, KA Day, PN Pachter, R TI Electronic structure and spectra of the ground and excited states of potential optical limiting materials. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLPJ, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 168-COMP BP U690 EP U690 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148102143 ER PT J AU Patton, ST Safriet, AJ Zabinski, JS AF Patton, ST Safriet, AJ Zabinski, JS TI Boundary lubrication studies of materials of relevance to MEMS using in situ contact condition monitoring. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 061-COLL BP U601 EP U601 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148101849 ER PT J AU Sankaran, B Tan, LS AF Sankaran, B Tan, LS TI Structure-property relationships of bis (ethylenedioxythienylnaphthalene) systems. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Universal Technol Corp, Dayton, OH 45432 USA. USAF, Res Lab, AFRL MLBP, Polymer Branch, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 117-POLY BP U549 EP U549 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JP UT WOS:000079148201700 ER PT J AU Schuman, LJ Bode, KS Dunlap, JT Hicks, BW AF Schuman, LJ Bode, KS Dunlap, JT Hicks, BW TI Production of green fluorescent protein-expressing oligodendrocyte precursor cell lines for transplantation studies of oligodendrocytes in spinal cord SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 429-CHED BP U430 EP U430 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148101273 ER PT J AU Tiffany, PS Powell, JW Johnson, JEB Balaich, GJ Chamberlin, RM Abney, KD AF Tiffany, PS Powell, JW Johnson, JEB Balaich, GJ Chamberlin, RM Abney, KD TI Free radical addition copolymerization of a cobalt dicarbollide monoacrylate ester complex. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Chem Res Ctr, Colorado Springs, CO 80840 USA. Univ Calif Los Alamos Natl Lab, Nucl & Radiochem Grp, Los Alamos, NM 87545 USA. RI Chamberlin, Rebecca/A-1335-2011 OI Chamberlin, Rebecca/0000-0001-6468-7778 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 640-CHED BP U490 EP U490 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148101484 ER PT J AU Trohalaki, S Pachter, R AF Trohalaki, S Pachter, R TI The utility of electron affinity as a QSAR descriptor in predictive toxicology. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 111-COMP BP U674 EP U674 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148102086 ER PT J AU Unroe, MR Evers, RC AF Unroe, MR Evers, RC TI A history of air force sponsored rigid-rod aromatic-heterocyclic polymer development: A salute to PBO. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 013-HIST BP U863 EP U863 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JN UT WOS:000079148102697 ER PT J AU Venkatasubramanian, N Nagvekar, DS Price, GE Vaia, RA Tan, LS Arnold, FE AF Venkatasubramanian, N Nagvekar, DS Price, GE Vaia, RA Tan, LS Arnold, FE TI Guest-host interactions in organic dye-doped matrix polymers. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Systran Fed Corp, Dayton, OH 45432 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. AFRL, MLBP, Polymer Branch, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 2 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 118-POLY BP U550 EP U550 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JP UT WOS:000079148201701 ER PT J AU Viggiano, AA Morris, RA Arnold, ST AF Viggiano, AA Morris, RA Arnold, ST TI Thermal decomposition in a variable temperature selected ion flow tube: A review of recent measurements. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Space Vehicles Directorate VSBP, Hanscom AFB, MA 01731 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD MAR 21 PY 1999 VL 217 MA 045-PHYS BP U289 EP U289 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 176JP UT WOS:000079148200848 ER PT J AU Normark, JW Williams, RF Hostettler, CF Ramey, M Moran, EL AF Normark, JW Williams, RF Hostettler, CF Ramey, M Moran, EL TI Redefining the practice of military pharmacy SO AMERICAN JOURNAL OF HEALTH-SYSTEM PHARMACY LA English DT Article ID IMPERFECT WORLD; MEDICATION USE; PUBLIC-POLICY; ISSUE; CARE AB Pharmacists throughout the U.S. health care system must keep pace with change or face being left behind. To move military pharmacists from a primarily distributive role to a clinical one, the Assistant Secretary of Defense for Health Affairs directed the Department of Defense Pharmacy Board of Directors to develop a plan to redefine the role of military pharmacists and technicians in ambulatory care. That document, summarized here, describes the future roles of military pharmacists and pharmacy technicians. The document was prepared with input from pharmacists and technicians, officers and enlisted members, working in day-to-day pharmacy operations. The complete document can be obtained by contacting Colonel James W. Normark, 1050 W. Perimeter Road, Andrews Air Force Base, MD 20762 (normaj@mgmc.af.mil). C1 USAF, Biomed Sci Corps Pharm, Andrews AFB, MD 20331 USA. USA, Med Command, San Antonio, TX 78234 USA. USN, BUMED, Bethesda, MD 20084 USA. US Coast Guard, Washington, DC 20593 USA. US Dept Def, Pharmacoecon Ctr, Ft Sam Houston, TX USA. RP Normark, JW (reprint author), USAF, Biomed Sci Corps Pharm, Andrews AFB, MD 20331 USA. NR 12 TC 2 Z9 2 U1 1 U2 1 PU AMER SOC HEALTH-SYSTEM PHARMACISTS PI BETHESDA PA 7272 WISCONSIN AVE, BETHESDA, MD 20814 USA SN 1079-2082 J9 AM J HEALTH-SYST PH JI Am. J. Health-Syst. Pharm. PD MAR 15 PY 1999 VL 56 IS 6 BP 568 EP 571 PG 4 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 178VL UT WOS:000079289800021 PM 10192694 ER PT J AU Adair, ER Mylacraine, KS Cobb, BL AF Adair, ER Mylacraine, KS Cobb, BL TI Physiological responses of human volunteers during partial body RF exposure to 2450 MHz pulsed and CW fields SO FASEB JOURNAL LA English DT Meeting Abstract C1 USAF, Res Lab, HEDR, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 15 PY 1999 VL 13 IS 5 SU S BP A743 EP A743 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 228JG UT WOS:000082132900553 ER PT J AU Ryan, KL Taylor, RL Lehnert, HM Mahajan, K Walters, TJ Mason, PA AF Ryan, KL Taylor, RL Lehnert, HM Mahajan, K Walters, TJ Mason, PA TI Plasma and adrenal catecholamines during 35-GHz microwave (MW) heating SO FASEB JOURNAL LA English DT Meeting Abstract C1 USAF, Res Lab, Directed Energy Bioeffects Div, Brooks AFB, TX 78235 USA. Trinity Univ, San Antonio, TX 78212 USA. Veridian Inc, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 15 PY 1999 VL 13 IS 5 SU S BP A743 EP A743 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 228JG UT WOS:000082132900554 ER PT J AU Seaman, RL Wohlfield, BJ AF Seaman, RL Wohlfield, BJ TI Activity and acoustic startle prepulse inhibition 3-4 hr after 3-nitropropionic acid injection SO FASEB JOURNAL LA English DT Meeting Abstract C1 USAF, Med Res Detachment, Microwave Bioeffects Branch, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 15 PY 1999 VL 13 IS 5 SU S BP A1102 EP A1102 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 228JG UT WOS:000082132902627 ER PT J AU Walters, TJ Mason, PA Lehnert, HM Mahajan, K Scholin, TL Ryan, KL AF Walters, TJ Mason, PA Lehnert, HM Mahajan, K Scholin, TL Ryan, KL TI HSP expression in the CNS may be dissociated from whole-body thermotolerance SO FASEB JOURNAL LA English DT Meeting Abstract C1 USAF, Res Lab, Directed Energy Bioeffects Div, Brooks AFB, TX 78235 USA. Veridian Inc, Brooks AFB, TX 78235 USA. Trinity Univ, San Antonio, TX 78212 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 15 PY 1999 VL 13 IS 5 SU S BP A743 EP A743 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 228JG UT WOS:000082132900557 ER PT J AU Jiao, CQ Garscadden, A Haaland, PD AF Jiao, CQ Garscadden, A Haaland, PD TI Ionization of trimethylsilane, (CH3)(3)SiH SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electron; ion; ionization; reaction; cross section ID RESONANCE MASS-SPECTROMETRY; CHEMICAL VAPOR-DEPOSITION; EXCITATION; SYSTEM; STEEL AB Cross sections for electron impact ionization of trimethylsilane from threshold to 70 eV have been measured using Fourier transform mass spectrometry. High resolution mass spectra show that the parent ion Si(CH3)(3)H+ is not formed by electron impact. Only one of the 15 ions produced by dissociative ionization lacks a silicon atom. The total ionization cross section is 1.5 X 10(-15) cm(2) at 70 eV.(CH3)(2)SiH+ and (CH3)(3)Si+ comprise over half of the ions produced by electron impact, but charge transfer reactions of (CH3)(2)SiH+ and lighter ions yield (CH3)(3)Si+ at pressure-time product in the 10(-7) Torr s range. The implication of this ion chemistry is that ion fluxes to the walls of trimethylsilane plasmas are predominantly (CH3)(3)Si+. (Int J Mass Spectrom 184 (1999) 83-88) (C) 1999 Elsevier Science B.V. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Mobium Enterprises Inc, Dayton, OH 45431 USA. RP Garscadden, A (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 12 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD MAR 15 PY 1999 VL 184 IS 1 BP 83 EP 88 DI 10.1016/S1387-3806(98)14270-7 PG 6 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 175VX UT WOS:000079117300009 ER PT J AU Croley, J Grimes, SR Merrill, G Johnson, DA AF Croley, J Grimes, SR Merrill, G Johnson, DA TI Tear and aqueous levels of famciclovir (penciclovir) after oral administration in the rabbit model SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Brooke Army Med Ctr, San Antonio, TX USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 1999 VL 40 IS 4 MA 463B423 BP S87 EP S87 PG 1 WC Ophthalmology SC Ophthalmology GA 178MF UT WOS:000079269200463 ER PT J AU Roberts, SE Holck, DE Ng, JD Lloyd, WC Dirks, MS AF Roberts, SE Holck, DE Ng, JD Lloyd, WC Dirks, MS TI Prospective clinical evaluation of wound healing after carbon dioxide laser upper lid blepharoplasty closed with polypropylene suture or octylcyanoacrylate (Dermabond (R)) tissue adhesive SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Brooke Army Med Ctr, San Antonio, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 1999 VL 40 IS 4 MA 152B112 BP S29 EP S29 PG 1 WC Ophthalmology SC Ophthalmology GA 178MF UT WOS:000079269200153 ER PT J AU Wetzel, PA Gregory, MH Martin, EL AF Wetzel, PA Gregory, MH Martin, EL TI Influence of Night Vision Goggles on head and eye movements during visual search SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 USAF, Res Lab, Mesa, AZ USA. Raytheon Syst Co, Visual Res Lab, Mesa, AZ USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 1999 VL 40 IS 4 MA 317B277 BP S59 EP S59 PG 1 WC Ophthalmology SC Ophthalmology GA 178MF UT WOS:000079269200318 ER PT J AU Allen, CN Jiang, ZG Teshima, K Darland, R Ikeda, M Nelson, CS Quigley, DI Yoshioka, T Allen, RG Rea, MA Grandy, DS AF Allen, CN Jiang, ZG Teshima, K Darland, R Ikeda, M Nelson, CS Quigley, DI Yoshioka, T Allen, RG Rea, MA Grandy, DS TI Orphanin-FQ/nociceptin (OFQ/N) modulates the activity of suprachiasmatic nucleus neurons SO JOURNAL OF NEUROSCIENCE LA English DT Article DE orphanin-FQ; nociceptin; suprachiasmatic nucleus; circadian rhythm; potassium current; calcium ID TISSUE DISTRIBUTION; ORL(1) RECEPTOR; RETINOHYPOTHALAMIC TRACT; INTERGENICULATE LEAFLET; FUNCTIONAL EXPRESSION; MEMBRANE-PROPERTIES; BRAIN-SLICES; RAT-BRAIN; IN-VITRO; FQ AB Neurons in the suprachiasmatic nucleus (SCN) constitute the principal circadian pacemaker of mammals. in situ hybridization studies revealed expression of orphanin-FQ/nociceptin (OFQ/N) receptor (NOR) mRNA in the SCN, whereas no expression of mRNA for preproOFQ/N (ppOFQ/N) was detected. The presence of OFQ/N peptide in the SCN was demonstrated by radioimmunoassay. SCN neurons (88%) responded dose-dependently to OFQ/N with an outward current (EC50 = 22.3 nM) that was reduced in amplitude by membrane hyperpolarization and reversed polarity near the theoretical potassium equilibrium potential. [Phe(1)psi(Ch(2)-NH)Gly(2)]OFQ/N(1 -13)NH2 (3 mu M), a putative NOR antagonist, activated a small outward current and significantly reduced the amplitude of the OFQ/N-stimulated current. OFQ/N reduced the NMDA receptor-mediated increase in intracellular Ca2+. When injected unilaterally into the SCN of Syrian hamsters housed in constant darkness, OFQ/N (1-50 pmol) failed to alter the timing of the hamsters' wheel-running activity However, injection of OFQ/N (0.160 pmol) before a brief exposure to light during the mid-subjective night significantly attenuated the light-induced phase advances of the activity rhythm. These data are consistent with the interpretation that OFQ/N acting ai:specific receptors modulates the activity of SCN neurons and, thereby, the response of the circadian clock to light. C1 Oregon Hlth Sci Univ, Ctr Res Occupat & Environm Toxicol, Portland, OR 97201 USA. Oregon Hlth Sci Univ, Dept Physiol & Pharmacol, Portland, OR 97201 USA. Oregon Hlth Sci Univ, Dept Cell & Dev Biol, Portland, OR 97201 USA. Oregon Hlth Sci Univ, Dept Mol & Med Genet, Portland, OR 97201 USA. Waseda Univ, Sch Human Sci, Dept Mol Neurobiol, Tokorozawa, Saitama 359, Japan. USAF, Res Lab, Biol Rhythums & Integrat Neurosci Res Inst, Brooks AFB, TX 78235 USA. RP Allen, CN (reprint author), Oregon Hlth Sci Univ, Ctr Res Occupat & Environm Toxicol, L606,3181 SW Sam Jackson Pk Rd, Portland, OR 97201 USA. FU NIA NIH HHS [AG10794]; NIDA NIH HHS [DA08562]; NINDS NIH HHS [NS036607] NR 51 TC 60 Z9 60 U1 0 U2 1 PU SOC NEUROSCIENCE PI WASHINGTON PA 11 DUPONT CIRCLE, NW, STE 500, WASHINGTON, DC 20036 USA SN 0270-6474 J9 J NEUROSCI JI J. Neurosci. PD MAR 15 PY 1999 VL 19 IS 6 BP 2152 EP 2160 PG 9 WC Neurosciences SC Neurosciences & Neurology GA 173BQ UT WOS:000078961400026 PM 10066268 ER PT J AU Carlson, JL AF Carlson, JL TI To the summit: 50 mountains that lure, inspire, and challenge. SO LIBRARY JOURNAL LA English DT Book Review C1 Vandenberg Air Force Base Lib, Vandenberg AFB, CA 93437 USA. RP Carlson, JL (reprint author), Vandenberg Air Force Base Lib, Vandenberg AFB, CA 93437 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD MAR 15 PY 1999 VL 124 IS 5 BP 100 EP 100 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 174WN UT WOS:000079059500154 ER PT J AU Huang, DH Lyo, SK AF Huang, DH Lyo, SK TI Photoluminescence spectra of n-doped double quantum wells in a parallel magnetic field SO PHYSICAL REVIEW B LA English DT Article ID 2-DIMENSIONAL ELECTRON-SYSTEMS; INPLANE MAGNETORESISTANCE; OPTICAL-TRANSITIONS; FERMI SURFACES; CONDUCTANCE; GASES; MASS AB We show that the photoluminescence (PL) line shapes from tunnel-split ground sublevels of n-doped thin double quantum wells (DQW's) are sensitively modulated by an in-plane magnetic field B-parallel to at low temperatures (T). The modulation is caused by the B-parallel to-induced distortion of the electronic structure. The latter arises from the relative shift of the energy-dispersion parabolas of the two quantum wells (QW's) in (k) over right arrow space, both in the conduction and valence bands, and formation of an anticrossing gap in the conduction band. Using a self-consistent density-functional theory, the PL spectra and the band-gap narrowing are calculated as a function of B-parallel to , T, and the homogeneous linewidths. The PL spectra from symmetric and asymmetric DQW's are found to show strikingly different behavior. In symmetric DQW's with a high density of electrons, two PL peaks are obtained at B-parallel to=0, representing the interband transitions between the pair of the upper (i.e., antisymmetric) levels and that of the lower (i.e., symmetric) levels of the ground doublets. As B-parallel to increases, the upper PL peak develops an N-type kink, namely a maximum followed by a minimum, and merges with the lower peak, which rises monotonically as a function of B-parallel to due to the diamagnetic energy. When the electron density is low, however, only a single PL peak, arising from the transitions between the lower levels, is obtained. In asymmetric DQW's, the PL spectra show mainly one dominant peak at all B-parallel to's In this case, the holes are localized in one of the QW's at low T and recombine only with the electrons in the same QW. At high electron densities, the upper PL peak shows an N-type kink like in symmetric DQW's. However, the lower peak is absent at low B-parallel to's because it arises from the inter-QW transitions. Reasonable agreement is obtained with recent data from GaAs/Al0.3Ga0.7As DQW's. [S0163-1829(99)00411-7]. C1 USAF, Res Lab, VSSS, Kirtland AFB, NM 87117 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Huang, DH (reprint author), USAF, Res Lab, VSSS, Kirtland AFB, NM 87117 USA. NR 24 TC 33 Z9 33 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1999 VL 59 IS 11 BP 7600 EP 7609 DI 10.1103/PhysRevB.59.7600 PG 10 WC Physics, Condensed Matter SC Physics GA 182PQ UT WOS:000079507700059 ER PT J AU France, JC Yaszemski, MJ Lauerman, WC Cain, JE Glover, JM Lawson, KJ Coe, JD Topper, SM AF France, JC Yaszemski, MJ Lauerman, WC Cain, JE Glover, JM Lawson, KJ Coe, JD Topper, SM TI A randomized prospective study of posterolateral lumbar fusion - Outcomes with and without pedicle screw instrumentation SO SPINE LA English DT Article DE instrumentation; lumbar vertebrae; spinal fusion; treatment outcome ID PAIN; FIXATION; SPINE AB Study Design. A prospective evaluation of the clinical and radiographic outcomes of 71 patients who underwent lumbar fusion, with or without transpedicular instrumentation. The patients completed a questionnaire that determined pain relief, medication use, return to work, and overall satisfaction with surgery. Objectives. To explore the effect, if any, of instrumentation on the outcome of lumbar fusion surgery, according to reports of the patients, and whether there is a correlation between the radiographic determination of a solid fusion and the same patient-reported outcome. Summary of Background Data. The literature on this topic reports pseudarthrosis rates from 0% to 57% and good excellent results from 56% to 95%. These studies provide no clear-cut recommendations concerning the effect of added lumbar instrumentation on patient-reported outcome in a prospective manner using concurrent control subjects. Methods. The patients were randomized to groups with and without instrumentation after deciding to undergo a lumbar fusion and consenting to enter the study. Radiographs were obtained and questionnaires filled out at 6 weeks, 6 months, 1 year, and 2 years after surgery. Results. There was no statistical difference in patient-reported outcome between the two groups. There was a slight nonsignificant trend toward increased radiographic fusion rate in the group with instrumentation that did not correlate with an increased patient-reported improvement rate. Conclusions. These results do not provide data that indicate a benefit in outcome from added instrumentation in elective lumbar fusions. C1 Mayo Clin & Mayo Med Sch, Dept Orthoped Surg, Rochester, MN 55905 USA. W Virginia Univ, Morgantown, WV 26506 USA. Georgetown Univ, Washington, DC USA. Orthoped Associates Milwaukee, Milwaukee, WI USA. Wilford Hall USAF Med Ctr, Uniformed Serv Univ Hlth Sci, San Antonio, TX 78236 USA. USAF, Acad Hosp, Uniformed Serv Univ Hlth Sci, Colorado Springs, CO USA. RP Yaszemski, MJ (reprint author), Mayo Clin & Mayo Med Sch, Dept Orthoped Surg, 200 1st St SW, Rochester, MN 55905 USA. NR 20 TC 132 Z9 148 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0362-2436 J9 SPINE JI SPINE PD MAR 15 PY 1999 VL 24 IS 6 BP 553 EP 560 DI 10.1097/00007632-199903150-00010 PG 8 WC Clinical Neurology; Orthopedics SC Neurosciences & Neurology; Orthopedics GA 177BH UT WOS:000079187200009 PM 10101819 ER PT J AU Rebholz, C Schneider, JM Voevodin, AA Steinebrunner, J Charitidis, C Logothetidis, S Leyland, A Matthews, A AF Rebholz, C Schneider, JM Voevodin, AA Steinebrunner, J Charitidis, C Logothetidis, S Leyland, A Matthews, A TI Structure, mechanical and tribological properties of sputtered TiAlBN thin films SO SURFACE & COATINGS TECHNOLOGY LA English DT Article DE mechanical and tribological properties; sputter deposition; structure; TiAlBN coatings ID TI-B-N; COATINGS AB TiAlBN films were produced by simultaneously sputtering from TiAl and TiB2 targets in Ar/N, mixtures at a substrate temperature of 150 degrees C. The goal of this investigation was to study the influence of the nitrogen content (0-40 at.%) on two sets of four coatings with B/Al ratios of approximately 1 and 5. All coatings showed very dense structures and were mainly found to be only partially crystalline. Evidence of Al, AlN, Ti, TiB2, TIN and BN bonding was observed in the XPS spectra, and correlation of the compositional and mechanical data showed that film hardness and elastic modulus decreased with the presence of a "soft" phase (Al, Tier amorphous BN). Hardness and elastic modulus values of up to 25 and 250 GPa, respectively, were found for TiAl0.3B1.7 coatings. Coatings with a similar elastic modulus to that of the steel substrate showed the best adhesion. Friction coefficient values between approximately 0.5 and 0.7 were recorded in sliding wear experiments against SAE52100 and WC/6%Co balls. Although friction coefficients could not be correlated to the amorphous BN contents, it was noted that low combined ball and disc wear rates were found for coatings containing large amounts of BN. Coatings with B/Al similar to 5 and elastic moduli of less than or equal to 290 GPa showed two orders of magnitude better sliding wear resistance against WC/6%Co balls compared to commercially available TiN. (C) 1999 Published by Elsevier Science S.A. All rights reserved. C1 Univ Hull, Res Ctr Surface Engn, Hull HU6 7RX, N Humberside, England. Linkoping Univ, Dept Phys, S-58183 Linkoping, Sweden. USAF, Wright Lab, Res Lab, Mat Directorate,LBT, Dayton, OH 45433 USA. Furtwangen Polytech Univ, D-78054 VS Schwenningen, Germany. Aristotelian Univ Salonika, Dept Phys, GR-54006 Salonika, Greece. RP Leyland, A (reprint author), Univ Hull, Res Ctr Surface Engn, Hull HU6 7RX, N Humberside, England. RI Schneider, Jochen/A-4701-2012; Voevodin, Andrey/I-6684-2013; Matthews, Allan/H-2394-2012; Leyland, Adrian/A-4714-2009; OI Matthews, Allan/0000-0002-9282-1425; Leyland, Adrian/0000-0002-5569-7293; Charitidis, Costas/0000-0003-1367-7603 NR 15 TC 47 Z9 48 U1 2 U2 14 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD MAR 12 PY 1999 VL 113 IS 1-2 BP 126 EP 133 DI 10.1016/S0257-8972(98)00840-8 PG 8 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 186VL UT WOS:000079750800017 ER PT J AU Dotan, I Viggiano, AA AF Dotan, I Viggiano, AA TI Rate constants for the reaction of O+ with NO as a function of temperature (300-1400 K) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DEPENDENCE AB We have measured the rate constants for the reaction of O+ ions with NO from room temperature to 1400 K. The reaction is slow (k = 8 X 10(-13) cm(3) s(-1)) at room temperature and the rate constant increases to 2.6 X 10(-12) cm(3) s(-1) at 1400 K. Comparison of the high-temperature data to drift tube data shows that rotational and translational energy are equally effective at controlling the rate constant, and that vibrational energy has at most a small effect on reactivity. Analysis of the data shows that the reaction proceeds by three different mechanisms. At the very low temperatures, we find a complex formation mechanism, and at the medium temperature range the behavior is interpreted to be a consequence of the correlation of O+ (S-4) and NO((2)Pi) with the excited states (3)A(1), B-3(1) of NO2+, which lie slightly above the reactants in energy. At the very high energy range, a third mechanism becomes important, probably the endothermic production of NO+((3)Sigma(+)). (C) 1999 American Institute of Physics. [S0021-9606(99)01110-1]. C1 USAF, Res Lab, Space Vehicle Directorate VSBP, Hanscom AFB, MA 01731 USA. Open Univ, Dept Nat & Life Sci, Tel Aviv, Israel. RP Viggiano, AA (reprint author), USAF, Res Lab, Space Vehicle Directorate VSBP, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 16 TC 15 Z9 15 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 8 PY 1999 VL 110 IS 10 BP 4730 EP 4733 DI 10.1063/1.478359 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 170XG UT WOS:000078831900006 ER PT J AU Steinhubl, SR Tan, WA Foody, JM Topol, EJ AF Steinhubl, SR Tan, WA Foody, JM Topol, EJ CA EPISTENT Investigators TI Incidence and clinical course of thrombotic thrombocytopenic purpura due to ticlopidine following coronary stenting SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Article AB Context Thrombotic thrombocytopenic purpura (TTP) is a rare and often fatal disorder characterized by thrombocytopenia, microangiopathic hemolytic anemia, mental status changes, and renal dysfunction. Ticlopidine hydrochloride is 1 of several drugs that have been associated with this disorder and is currently used routinely in the approximately 500 000 patients per year in the United States who undergo a percutaneous coronary intervention involving a stent. Objectives To determine the incidence and describe the clinical course of TTP due to ticlopidine therapy following stenting. Design Retrospective analysis of cohort of all patients undergoing coronary stenting at the Evaluation of Platelet IIb/IIIa Inhibitor for Stenting (EPISTENT) study sites. Setting Sixty-three centers throughout the United States and Canada. Patients A total of 43 322 patients who underwent a percutaneous coronary intervention and received a coronary stent during a 1-year period from 1996 to 1997. Main Outcome Measures Cases of TTP following stenting during the 1-year period to determine the incidence of TTP due to ticlopidine therapy following coronary stenting. Additional cases were collected from these and other centers across North America to further describe the clinical presentation and course of TTP due to ticlopidine therapy following stenting. Results Nine cases of TTP following stenting were recognized at the 63 centers during the specified period, giving an incidence of 1 case per 4814 patients treated (0.02%; 95% confidence interval, 1 case per 2533 to 1 case per 10541 patients treated). Ten additional cases of TTP related to ticlopidine therapy following stenting were identified from other centers, were identified from the primary centers outside the predefined period, or involved a noncoronary stent. Four patients (21%) received ticlopidine far 2 weeks or fewer, 14 patients (74%) for 2 to 4 weeks, and 1 patient (5%) for 8 weeks. The mean time of ticlopidine treatment prior to TTP diagnosis was 22 days (range, 5-60 days). The overall mortality rate was 21% (4/19), with all 4 deaths occurring in patients not treated with plasmapheresis, whereas there were no deaths among the 13 patients who received plasmapheresis, Conclusion The findings of a TTP incidence of 0.02% in our cohort of ticlopidine-treated patients following coronary stenting suggests that TTP occurs much more commonly in this population than the estimated incidence of 0.0004% in the general population. The mortality rate for this rare complication exceeds 20%, Limiting ticlopidine therapy to 2 weeks after stenting does not prevent the development of TTP. Rapid diagnosis and treatment that includes plasmapheresis are critical for improved survival. C1 Wilford Hall USAF Med Ctr, Dept Cardiol, Lackland AFB, TX 78236 USA. Cleveland Clin Fdn, Dept Cardiol, Cleveland, OH 44195 USA. Cleveland Clin Fdn, Joseph J Jacobs Ctr Thrombosis & Vasc Biol, Cleveland, OH 44195 USA. RP Steinhubl, SR (reprint author), Wilford Hall USAF Med Ctr, Dept Cardiol, 2200 Bergquist Dr, Lackland AFB, TX 78236 USA. EM steinhubl@whmc.af.mil OI Topol, Eric/0000-0002-1478-4729 NR 19 TC 157 Z9 160 U1 1 U2 2 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD MAR 3 PY 1999 VL 281 IS 9 BP 806 EP 810 DI 10.1001/jama.281.9.806 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA 170KF UT WOS:000078804300030 PM 10071001 ER PT J AU Coalson, JJ Winter, V Yoder, BA AF Coalson, JJ Winter, V Yoder, BA TI Cell turnover in baboons with chronic lung disease (CLD) SO AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE LA English DT Meeting Abstract C1 Univ Texas, Hlth Sci Ctr, Dept Pathol, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, Dept Pathol, San Antonio, TX 78784 USA. SW Fdn Biomed Res, Dept Pathol, San Antonio, TX 78284 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER LUNG ASSOC PI NEW YORK PA 1740 BROADWAY, NEW YORK, NY 10019 USA SN 1073-449X J9 AM J RESP CRIT CARE JI Am. J. Respir. Crit. Care Med. PD MAR PY 1999 VL 159 IS 3 SU S BP A256 EP A256 PG 1 WC Critical Care Medicine; Respiratory System SC General & Internal Medicine; Respiratory System GA 230DT UT WOS:000082237101384 ER PT J AU Shenberger, J Dixon, P AF Shenberger, J Dixon, P TI Calcitonin gene-related peptide increases DNA synthesis in human bronchial smooth muscle cells. SO AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Dept Pediat, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER LUNG ASSOC PI NEW YORK PA 1740 BROADWAY, NEW YORK, NY 10019 USA SN 1073-449X J9 AM J RESP CRIT CARE JI Am. J. Respir. Crit. Care Med. PD MAR PY 1999 VL 159 IS 3 SU S BP A531 EP A531 PG 1 WC Critical Care Medicine; Respiratory System SC General & Internal Medicine; Respiratory System GA 230DT UT WOS:000082237102927 ER PT J AU Evans, MW AF Evans, MW TI Messianic inversion in Stephen Crane's The 'Monster' SO AMERICAN LITERARY REALISM 1870-1910 LA English DT Article C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Evans, MW (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU MCFARLAND & CO INC PI JEFFERSON PA BOX 611, JEFFERSON, NC 28640 USA SN 0002-9823 J9 AM LIT REALISM JI Am. Lit. Realism 1870-1910 PD SPR PY 1999 VL 31 IS 3 BP 58 EP 62 PG 5 WC Literature, American SC Literature GA 202LF UT WOS:000080653200005 ER PT J AU Wang, J Ashley, K Marlow, D England, EC Carlton, O AF Wang, J Ashley, K Marlow, D England, EC Carlton, O TI Field method for the determination of hexavalent chromium by ultrasonication and strong anion exchange solid phase extraction SO ANALYTICAL CHEMISTRY LA English DT Article ID LIQUID-CHROMATOGRAPHY; WELDING FUMES; ENVIRONMENTAL-SAMPLES; CONTAMINATED SOILS; FLOW-INJECTION; WATER; SPECIATION; CR(VI); OPTIMIZATION; PESTICIDES AB A simple, fast, sensitive, and economical held method was developed and evaluated for the determination of hexavalent chromium (Cr-VI) in environmental and workplace air samples. By means of ultrasonic extraction in combination with a strong anion-exchange solid-phase extraction (SAE-SPE) technique, the filtration, isolation, and determination of Cr-VI in the presence of trivalent chromium (Cr-III) and potential interferents was achieved. The method entails (1) ultrasonication in basic ammonium buffer solution to extract Cr-VI from environmental matrixes; (2) SAE-SPE to separate Cr-VI from Cr-III and interferences; (3) elution/acidification of the eluate; (4) complexation of chromium with 1,5-diphenylcarbazide; and (5) spectrophotometric determination of the colored chromium-diphenylcarbazone complex. Several critical parameters were optimized in order to effect the extraction of both soluble (K2CrO4) and insoluble (PbCrO4) forms of Cr-VI without inducing Cr-III oxidation or Cr-VI reduction. The method allowed for the dissolution and purification of Cr-VI from environmental and workplace air sample matrixes for up to 24 samples simultaneously in less than 90 min (including ultrasonication). The results demonstrated that the method was simple, fast, quantitative, and sufficiently sensitive for the determination of occupational exposures of Cr-VI. The method is applicable for on-site monitoring of Cr-VI in environmental and industrial hygiene samples. C1 NIOSH, US Dept HHS, Ctr Dis Control & Prevent, Cincinnati, OH 45226 USA. USAF, Human Syst Ctr, Ind Hyg Branch, Brooks AFB, TX 78235 USA. RP Ashley, K (reprint author), NIOSH, US Dept HHS, Ctr Dis Control & Prevent, Cincinnati, OH 45226 USA. RI Ashley, Kevin/C-9005-2011 NR 40 TC 66 Z9 68 U1 1 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 1 PY 1999 VL 71 IS 5 BP 1027 EP 1032 DI 10.1021/ac980501r PG 6 WC Chemistry, Analytical SC Chemistry GA 171AR UT WOS:000078840300028 PM 10079763 ER PT J AU Haddock, CK Talcott, GW Klesges, RC Lando, H AF Haddock, CK Talcott, GW Klesges, RC Lando, H TI An examination of cigarette brand switching to reduce health risks SO ANNALS OF BEHAVIORAL MEDICINE LA English DT Article ID FAGERSTROM TOLERANCE QUESTIONNAIRE; NICOTINE DEPENDENCE; SMOKING CESSATION; HARM REDUCTION; UNITED-STATES; LOSE WEIGHT; FOLLOW-UP; POPULATION; ADULTS; CARE AB This study examined cigarette brand switching to reduce health risk in a population of young smokers (N = 7,998) entering United States Air Force Basic Military Training. Because of a comprehensive tobacco bun during training, all smokers were abstinent during the study. Results from this investigation suggested that brand switching to reduce health risks was common among current smokers (31.3% of males; 32.3% of females). Brand switchers smoked fewer cigarettes, were more likely to smoke low-yield brands, had lower scores on a measure of nicotine dependency, and were more confident they could remain abstinent following training. Other discriminators of smokers who had switched brands from other smokers included using smoking to control appetite, greater proclivity to attempt smoking cessation, engaging in fewer safety risk, and healthier dietary composition. Finally, brand switchers quit smoking at a higher rate than other smokers (12.5% versus 11.1%) during the year following basic military training. However a multivariate logistic regression model that controlled for demographic factors and smoking history suggested that brand switching was not a statistically significant predictor of smoking cessation during the follow-up period. C1 Univ Missouri, Dept Psychol, Kansas City, MO 64110 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Univ Memphis, Prevent Ctr, Memphis, TN 38152 USA. Univ Minnesota, Minneapolis, MN 55455 USA. RP Haddock, CK (reprint author), Univ Missouri, Dept Psychol, 5319 Holmes St, Kansas City, MO 64110 USA. FU NHLBI NIH HHS [HL53478] NR 47 TC 10 Z9 10 U1 0 U2 1 PU SOC BEHAVIORAL MEDICINE PI MIDDLETON PA 7611 ELMWOOD AVE, STE 201, MIDDLETON, WI 53562-3161 USA SN 0883-6612 J9 ANN BEHAV MED JI Ann. Behav. Med. PD SPR PY 1999 VL 21 IS 2 BP 128 EP 134 DI 10.1007/BF02908293 PG 7 WC Psychology, Multidisciplinary SC Psychology GA 297WQ UT WOS:000086106000004 PM 10499133 ER PT J AU Pudavar, HE Joshi, MP Prasad, PN Reinhardt, BA AF Pudavar, HE Joshi, MP Prasad, PN Reinhardt, BA TI High-density three-dimensional optical data storage in a stacked compact disk format with two-photon writing and single photon readout SO APPLIED PHYSICS LETTERS LA English DT Article ID MEMORY; INFORMATION AB Using a polymer block doped with a highly efficient two-photon dye, we have achieved a high density data storage with gray-scale control in multiple planes as stacked compact disks at a separation of 10 mu m. The absorption and fluorescence of the dye at the written spot shift to a longer wavelength, permitting an easy fluorescence mode readout with a linear excitation using an inexpensive laser source. The storage capacity in this case is estimated to be 10(12) bits/cm(3). (C) 1999 American Institute of Physics. [S0003-6951(99)03409-9]. C1 SUNY Buffalo, Photon Res Lab, Dept Chem & Phys, Buffalo, NY 14260 USA. USAF, Polymer Branch, WL MLBP Mat Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Pudavar, HE (reprint author), SUNY Buffalo, Photon Res Lab, Dept Chem & Phys, Buffalo, NY 14260 USA. NR 13 TC 171 Z9 179 U1 3 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 1 PY 1999 VL 74 IS 9 BP 1338 EP 1340 DI 10.1063/1.123543 PG 3 WC Physics, Applied SC Physics GA 173ZQ UT WOS:000079010000050 ER PT J AU Franck, RE AF Franck, RE TI Citizen soldiers. SO ARMED FORCES & SOCIETY LA English DT Book Review C1 USAF Acad, Dept Econ & Geog, Colorado Springs, CO 80840 USA. RP Franck, RE (reprint author), USAF Acad, Dept Econ & Geog, Colorado Springs, CO 80840 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU TRANSACTION PERIOD CONSORTIUM PI PISCATAWAY PA DEPT 4010, RUTGERS UNIV, 35 BERRUE CIRCLE, PISCATAWAY, NJ 08854-8042 USA SN 0095-327X J9 ARMED FORCES SOC JI Armed Forces Soc. PD SPR PY 1999 VL 25 IS 3 BP 527 EP 529 DI 10.1177/0095327X9902500310 PG 3 WC Political Science; Sociology SC Government & Law; Sociology GA 418EH UT WOS:000167877600009 ER PT J AU Miller, MD Gossum, RS AF Miller, MD Gossum, RS TI "Cigar wrap" technique for gracilis augmentation in hamstring anterior cruciate ligament reconstruction SO ARTHROSCOPY LA English DT Article DE anterior cruciate ligament reconstruction; hamstring; graft ID TENDONS; BONE AB The use of Hamstring grafts for anterior cruciate ligament reconstruction is becoming increasingly popular Most surgeons use a four-stranded graft consisting of double-stranded semitendinosus and gracilis tendons. The gracilis tendon, in addition to being smaller in diameter, is often shorter and more diminutive at its muscular end. We developed a technique for supplementing this tendon using excess semitendinosus tendon. This allows enhanced tibial tunnel fit and improved graft fixation. C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Miller, MD (reprint author), 112 Charles Rd, San Antonio, TX 78209 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0749-8063 J9 ARTHROSCOPY JI Arthroscopy PD MAR PY 1999 VL 15 IS 2 BP 223 EP 225 DI 10.1053/ar.1999.v15.015022 PG 3 WC Orthopedics; Surgery SC Orthopedics; Surgery GA 174CK UT WOS:000079016400020 PM 10210085 ER PT J AU Harriman, LG Colliver, DG Hart, KQ AF Harriman, LG Colliver, DG Hart, KQ TI New weather data for energy calculations SO ASHRAE JOURNAL LA English DT Article AB HVAC systems must counteract weather forces when outdoor temperature or humidity moves away from an acceptable range for safety and comfort. Consequently, a clear understanding of weather behavior is helpful for system designers and operators. Shortcomings in that understanding are often at the root of problems involving poor indoor air quality and premature deterioration of buildings and HVAC equipment. C1 Mason Grant, Res, Portsmouth, NH USA. Univ Kentucky, Dept Agr & Biosyst Engn, Lexington, KY USA. USAF, Civil Engn Support Agcy, Tyndall AFB, Panama City, FL USA. RP Harriman, LG (reprint author), Mason Grant, Res, Portsmouth, NH USA. NR 16 TC 6 Z9 6 U1 0 U2 0 PU AMER SOC HEATING REFRIGERATING AIR-CONDITIONING ENG, INC, PI ATLANTA PA 1791 TULLIE CIRCLE NE, ATLANTA, GA 30329 USA SN 0001-2491 J9 ASHRAE J JI ASHRAE J. PD MAR PY 1999 VL 41 IS 3 BP 31 EP + PG 7 WC Thermodynamics; Construction & Building Technology; Engineering, Mechanical SC Thermodynamics; Construction & Building Technology; Engineering GA 235EN UT WOS:000082527200010 ER PT J AU Pravdo, SH Rabinowitz, DL Helin, EF Lawrence, KJ Bambery, RJ Clark, CC Groom, SL Levin, S Lorre, J Shaklan, SB Kervin, P Africano, JA Sydney, P Soohoo, V AF Pravdo, SH Rabinowitz, DL Helin, EF Lawrence, KJ Bambery, RJ Clark, CC Groom, SL Levin, S Lorre, J Shaklan, SB Kervin, P Africano, JA Sydney, P Soohoo, V TI The Near-Earth Asteroid Tracking (NEAT) Program: An automated system for telescope control, wide-field imaging, and object detection SO ASTRONOMICAL JOURNAL LA English DT Article DE instrumentation : detectors; minor planets, asteroids; techniques : image processing ID MAIN-BELT ASTEROIDS; APPROACHING ASTEROIDS; SUFFICIENT SOURCE; SIZE; DISTRIBUTIONS; 1996-PW AB The Near-Earth Asteroid Tracking (NEAT) system operates autonomously at the Maul Space Surveillance Site on the summit of the extinct Haleakala Volcano Crater, Hawaii. The program began in 1995 December and continues with an observing run every month. Its astrometric observations result in discoveries of near-Earth objects (NEOs), both asteroids (NEAs) and comets, and other unusual minor planets. Each six-night run NEAT covers about 10% of the accessible sky, detects thousands of asteroids, and detects two to five NEAs. NEAT has also contributed more than 1500 preliminary designations of minor planets and 26,000 detections of main-belt asteroids. This paper presents a description of the NEAT system and discusses its capabilities, including sky coverage, limiting magnitude, and detection efficiency. NEAT is an effective discoverer of NEAs larger than 1 km and is a major contributor to NASA's goal of identifying all NEAs of this size. An expansion of NEAT into a network of three similar systems would be capable of discovering 90% of the 1 km and larger NEAs within the next 10-40 yr, while serving the additional role of satellite detection and tracking for the US Air Force. Daily updates of NEAT results during operational periods can be found at JPL's Web site (http://huey.jpl.nasa.gov/ similar to spravdo/neat.html). The images and information about the detected objects, including times of observation, positions, and magnitudes are made available via NASA's SkyMorph program. C1 CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. USAF, Res Labs, Kihei, HI 96753 USA. RP Pravdo, SH (reprint author), CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA. NR 24 TC 51 Z9 51 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD MAR PY 1999 VL 117 IS 3 BP 1616 EP 1633 DI 10.1086/300769 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 187KZ UT WOS:000079786900043 ER PT J AU Ross, M Walsh, K AF Ross, M Walsh, K TI Case review - Treating low back pain its a middle-age recreational athlete SO ATHLETIC THERAPY TODAY LA English DT Article C1 USAF Acad, Dept Biol, USAF Acad, CO 80840 USA. E Carolina Univ, Greenville, NC 27858 USA. RP Ross, M (reprint author), USAF Acad, Dept Biol, USAF Acad, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU HUMAN KINETICS PUBL INC PI CHAMPAIGN PA 1607 N MARKET ST, CHAMPAIGN, IL 61820-2200 USA SN 1078-7895 J9 ATHLET THER TODAY JI Athlet. Ther. Today PD MAR PY 1999 VL 4 IS 2 BP 22 EP 23 PG 2 WC Rehabilitation; Sport Sciences SC Rehabilitation; Sport Sciences GA 283NY UT WOS:000085282700007 ER PT J AU Balldin, UI Tong, A Marshall, JA Regna, M AF Balldin, UI Tong, A Marshall, JA Regna, M TI Premature ventricular contractions during +Gz with and without pressure breathing and extended coverage anti-G suit SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE cardiac dysrhythmia; EKG; acceleration; G-exposure; G-protection; aerial combat maneuvers ID CENTRIFUGE AB Background: High +Gz is known to provoke cardiac dysrhythmias. Pressure breathing during G (PBG) and extended coverage anti-G suits (ECCS) are used to enhance +Gz-endurance and reduce fatigue during high +Gz flying. It is not known whether PBC in combination with EGGS increases the risk for premature Ventricular contractions (PVC). Hypothesis: PEG in combination with EGGS increases the risk of PVCs during high +Gz-loads. Methods: Retrospective data were obtained from 14 subjects exposed to three different simulated aerial combat sorties each, in the centrifuge with a standard anti-C suit ensemble or with PEG in combination with EGGS. Each sortie consisted of a gradual onset C-exposure (COR) and three simulated aerial combat maneuvers (SACM) containing four cycles of a +4.5 to +7 GzSACM; four cycles of +4 to +9 Gz tactical aerial combat maneuver (TACM) with several rapid transitions from;4 or +5 Gz to +8 or +9 Gz; and four cycles of +5 to +9 Gz SACM (5-9 SACM) with four cycles. ECG was recorded during the +Gz exposures to reveal any cardiac dysrhythmias. Results and Conclusions: No PVCs occurred during the GORs. During 4.5-7 SACMs, TACMs, and 5-9 SACMs there were 83, 50, and 24 PVCs with standard equipment, respectively, and 63, 54, and 39 PVCs With PBC and EGGS, respectively. There was no statistically significant difference between the equipment in any of the different types of +Gz exposures. No episodes of supraventricular tachycardia or relative bradycardia were found with either equipment. C1 USA, Res Lab, Flight Stress Protect Div, Brooks AFB, TX USA. RP Balldin, UI (reprint author), AFRL, HEP, Crew Technol Div, Suite 25,2504 Gillingham Dr, Brooks AFB, TX 78235 USA. NR 14 TC 2 Z9 2 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 1999 VL 70 IS 3 BP 209 EP 212 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 174BZ UT WOS:000079015400001 PM 10102730 ER PT J AU Glickman-Weiss, EL Nelson, AG Hearon, CM Prisby, R Caine, N AF Glickman-Weiss, EL Nelson, AG Hearon, CM Prisby, R Caine, N TI Thermal and metabolic responses of women with high fat versus low fat body composition during exposure to 5 and 27 degrees C for 120 min SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE temperature regulation; gender differences; body composition ID COLD-WATER; EXERCISING MEN; INSULATION AB Background: Men with high fat body composition maintain higher core temperatures, and lower aerobic metabolic rates than their low fat counterparts thus, verifying the insulatory benefit of body fat. Females, on average have more body fat and less muscle mass than males, and may maintain rectal temperature (T-re) at a tower energy cost. Methods: The present investigation dichotomized female subjects by percent fat (low fat; n = 3, LF = 19.2 +/- 3% vs. high fat; n = 4 HF: 29.9 +/- 3%) to elucidate the thermal and metabolic responses during acute exposure to 5 and 27 degrees C air for 120 min. An ANOVA was used to examine the following: T-re (degrees C), mean skin temperature (T-sk; degrees C) oxygen consumption (V) over dot O-2; ml.kg(-1).min(-1) and tissue insulation (I; degrees C.m(2).W-1). For T-re, a significant fat X time interaction (p < 0.05) was demonstrated at both 5 and 27 degrees C, whereby T-re tended to be lower in the LF group than the HF group, (V) over dot O-2 at 5 degrees C demonstrated a main effect for time only. For I, a main effect for time was noted at 5 degrees C. Also for I, a trend (p = 0.06) toward a main effect of fat during exposure to 5 degrees C was noted while at 27 degrees C a main effect (p < 0.05) was demonstrated. Results: From this data it appears that under these conditions, the HF group demonstrated higher T-re and I values than their LF counterparts that was not accompanied with a differential response with respect to aerobic metabolic rate. Thus, the impact of body composition on energy expenditure to maintain T-re differs between LF and HF males and females. C1 Kent State Univ, Exercise Sci Lab, Kent, OH 44242 USA. Louisiana State Univ, Dept Kinesiol, Baton Rouge, LA 70803 USA. KRUG Life Sci, Armstrong Lab, Brooks AFB, TX USA. RP Glickman-Weiss, EL (reprint author), Kent State Univ, Exercise Sci Lab, 163E MACC Annex, Kent, OH 44242 USA. NR 17 TC 11 Z9 11 U1 2 U2 6 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 1999 VL 70 IS 3 BP 284 EP 288 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 174BZ UT WOS:000079015400013 PM 10102742 ER PT J AU Israel, K AF Israel, K TI Use manned-unmanned mix SO AVIATION WEEK & SPACE TECHNOLOGY LA English DT Letter C1 USAF, Washington, DC 20330 USA. RP Israel, K (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL INC PI NEW YORK PA 1221 AVENUE OF THE AMERICAS, NEW YORK, NY 10020 USA SN 0005-2175 J9 AVIAT WEEK SPACE TEC JI Aviat. Week Space Technol. PD MAR 1 PY 1999 VL 150 IS 9 BP 6 EP 6 PG 1 WC Engineering, Aerospace SC Engineering GA 171ZY UT WOS:000078897900001 ER PT J AU Kramer, HR AF Kramer, HR TI Be more specific SO AVIATION WEEK & SPACE TECHNOLOGY LA English DT Letter C1 USAF, Washington, DC 20330 USA. RP Kramer, HR (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL INC PI NEW YORK PA 1221 AVENUE OF THE AMERICAS, NEW YORK, NY 10020 USA SN 0005-2175 J9 AVIAT WEEK SPACE TEC JI Aviat. Week Space Technol. PD MAR 1 PY 1999 VL 150 IS 9 BP 6 EP 6 PG 1 WC Engineering, Aerospace SC Engineering GA 171ZY UT WOS:000078897900005 ER PT J AU Chesley, JA Wenger, MS AF Chesley, JA Wenger, MS TI Transforming an organization: Using models to foster a strategic conversation SO CALIFORNIA MANAGEMENT REVIEW LA English DT Article ID IMPLEMENTATION AB To lead the reinvention of government, many federal agencies are searching for understandable, practical, and effective models to frame strategic change. Executives hope to find strategic models that offer simple, direct solutions to their problems. However, existing models of strategy must be transformed to fit an organization just as the organization must be transformed in light of the model. The model and the organization co-evolve. This is illustrated through a longitudinal case study of the National Reconnaissance Office, which adopted the "Balanced Scorecard" as a strategic management and performance measurement system. This article develops and presents a framework of mutual adaptation to clarify the variety of inter-related changes required in the strategy formulation and implementation. C1 Wenger & Wenger Consulting, Fairfax, VA USA. USAF Acad, Dept Management, Colorado Springs, CO 80840 USA. RP Chesley, JA (reprint author), Wenger & Wenger Consulting, Fairfax, VA USA. NR 20 TC 14 Z9 14 U1 0 U2 5 PU UNIV CALIF PI BERKELEY PA GRAD SCH BUSINESS ADMIN, BERKELEY, CA 94720 USA SN 0008-1256 J9 CALIF MANAGE REV JI Calif. Manage. Rev. PD SPR PY 1999 VL 41 IS 3 BP 54 EP + PG 22 WC Business; Management SC Business & Economics GA 196ED UT WOS:000080295300004 ER PT J AU Wheeler, JL Regian, JW AF Wheeler, JL Regian, JW TI The use of a cognitive tutoring system in the improvement of the abstract reasoning component of word problem solving SO COMPUTERS IN HUMAN BEHAVIOR LA English DT Article DE word problem solving; abstract reasoning; cognitive tutoring system; computer based training ID EXAMPLES AB This study evaluated the Word Problem Solving (WPS) Tutor's ability to improve the abstract reasoning component of word problem solving. Six hundred and thirty-two ninth grade students were assigned to three groups: a control group exposed to traditional group instruction, a placebo group exposed to traditional group instruction plus a computerized word problem solving environment with no active tutoring, and an experimental group exposed to traditional group instruction and a computerized word problem solving environment with active tutoring. A paper and pencil test was administered to students at the beginning of the school year, at mid-term, and at the end of the school year and was used to compare the performance of the three groups on the concrete and abstract components of word problem solving. Results indicated that WPS-Tutored students improved significantly more than either the control group or the placebo group on both the abstract and concrete reasoning subtests. However, performance gains on the abstract subtest were not as large as the gains on the concrete subtest. Implications for math education and suggestions for future research and development efforts are discussed. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Mei Technol, San Antonio, TX 78239 USA. USAF, Res Lab, AFRL, HEA 1, Brooks AFB, TX 78235 USA. RP Wheeler, JL (reprint author), Mei Technol, Suite 450,8930 Fourwinds Dr, San Antonio, TX 78239 USA. NR 28 TC 13 Z9 13 U1 1 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0747-5632 J9 COMPUT HUM BEHAV JI Comput. Hum. Behav. PD MAR PY 1999 VL 15 IS 2 BP 243 EP 254 DI 10.1016/S0747-5632(99)00021-7 PG 12 WC Psychology, Multidisciplinary; Psychology, Experimental SC Psychology GA 195CK UT WOS:000080231400010 ER PT J AU Gilson, RT Milum, E AF Gilson, RT Milum, E TI Calciphylaxis: Case report and treatment review SO CUTIS LA English DT Article ID CHRONIC-RENAL-FAILURE; CALCIFYING PANNICULITIS; PARATHYROIDECTOMY; DISEASE AB We present the case of a 57-year-old white woman with chronic renal failure as well as severely painful, firm, indurated plaques on the thighs and lower extremities. The plaques progressed to involve larger areas with associated local ulceration and necrosis. Laboratory testing revealed hyperparathyroidism, and incisional biopsy confirmed calcifying panniculitis. C1 Brooke Army Med Ctr, Wilford Hall USAF Med Ctr, Dept Dermatol, San Antonio, TX USA. RP Gilson, RT (reprint author), Brooke Army Med Ctr, Wilford Hall USAF Med Ctr, Dept Dermatol, San Antonio, TX USA. NR 13 TC 11 Z9 11 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD MAR PY 1999 VL 63 IS 3 BP 149 EP 153 PG 5 WC Dermatology SC Dermatology GA 179AJ UT WOS:000079301100008 PM 10190064 ER PT J AU Lash, LH Lipscomb, JC Putt, DA Parker, JC AF Lash, LH Lipscomb, JC Putt, DA Parker, JC TI Glutathione conjugation of trichloroethylene in human liver and kidney: Kinetics and individual variation SO DRUG METABOLISM AND DISPOSITION LA English DT Article ID BASAL-LATERAL MEMBRANE; PROXIMAL TUBULAR CELLS; HUMAN HEPATOCYTES; METABOLISM; RATS; TOXICITY; TUMORS; BIOTRANSFORMATION; CARCINOGENICITY; INHALATION AB Isolated human hepatocytes exhibited time-, trichloroethylene (Tri) concentration-, and cell concentration-dependent formation of S-(1,2-dichlorovinyl)glutathione (DCVG) in incubations in sealed flasks with 25 to 10,000 ppm Tri in the headspace, corresponding to 0.011 to 4.4 mM in hepatocytes, Maximal formation of DCVG (22.5 +/- 8.3 nmol/120 min per 10(6) cells) occurred with 500 ppm Tri, Time-, protein concentration-, and both Tri and GSH concentration-dependent formation of DCVG were observed in liver and kidney subcellular fractions. Two kinetically distinct systems were observed in both cytosol and microsomes from pooled liver samples, whereas only one system was observed in subcellular fractions from pooled kidney samples. Liver cytosol exhibited apparent K-m values (mu M Tri) of 333 and 22.7 and V-max values (nmol DCVG formed/min per mg protein) of 8.77 and 4.27; liver microsomes exhibited apparent K-m values of 250 and 29.4 and V-max values of 3.10 and 1.42; kidney cytosol and microsomes exhibited apparent K-m values of 26.3 and 167, respectively, and V-max values of 0.81 and 6.29, respectively. DCVG formation in samples of liver cytosol and microsomes from 20 individual donors exhibited a 6.5-fold variation in microsomes but only a 2.4-fold variation in cytosol. In coincubations of pooled liver cytosol and microsomes, addition of an NADPH-regenerating system produced marked inhibition of DCVG formation, but addition of GSH had no effect on cytochrome P-450-catalyzed formation of chloral hydrate. These results indicate that both human kidney and liver have significant capacity to catalyze DCVG formation, indicating that the initial step of the GSH-dependent pathway is not limiting in the formation of nephrotoxic and nephrocarcinogenic metabolites. C1 Wayne State Univ, Sch Med, Dept Pharmacol, Detroit, MI 48201 USA. USAF, Res Lab, Toxicol Branch, Wright Patterson AFB, OH 45433 USA. US EPA, Natl Ctr Environm Assessment, Washington, DC 20460 USA. RP Lash, LH (reprint author), Wayne State Univ, Sch Med, Dept Pharmacol, 540 E Canfield Ave, Detroit, MI 48201 USA. OI Lash, Lawrence/0000-0003-3239-4481 FU NIDDK NIH HHS [K04-DK02090] NR 38 TC 26 Z9 26 U1 0 U2 0 PU AMER SOC PHARMACOLOGY EXPERIMENTAL THERAPEUTICS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0090-9556 J9 DRUG METAB DISPOS JI Drug Metab. Dispos. PD MAR PY 1999 VL 27 IS 3 BP 351 EP 359 PG 9 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 172DT UT WOS:000078908500006 PM 10064565 ER PT J AU Wood, AW Wood, WD AF Wood, AW Wood, WD TI Integral equation methods for electromagnetic scattering from cavities SO DYNAMICS OF CONTINUOUS DISCRETE AND IMPULSIVE SYSTEMS LA English DT Article AB We investigate the electromagnetic scattering caused by a cavity-backed aperture in an infinite, perfectly conducting ground plane. We derive integral representations based on Maxwell's Equations for the electromagnetic fields in the scattering domain, and employ the boundary integral method to obtain a set of integral equations on the boundary of the cavity. We obtain accurate and efficient numerical solutions for the equations using the method of moments. We demonstrate the solvability of the integral equations at all frequencies. AMS (MOS) subject classification: 45, 65. C1 USAF, Inst Technol, Dept Math & Stat, Wright Patterson AFB, OH 45433 USA. USAF, Wright Lab, Electromagnet Div, Wright Patterson AFB, OH 45433 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU WATAM PRESS PI WATERLOO PA C/O DCDIS JOURNAL, UNIV WATERLOO, DEPT APPLIED MATHEMATICS, WATERLOO, ONTARIO N2L 3G1, CANADA SN 1201-3390 J9 DYN CONTIN DISCRET I JI Dyn. Contin. Discret. Impuls. Syst. PD MAR PY 1999 VL 5 IS 1-4 BP 473 EP 483 PG 11 WC Mathematics, Applied SC Mathematics GA 190PW UT WOS:000079973800041 ER PT J AU Merzlak, P AF Merzlak, P TI Passchendaele and the Royal Navy SO HISTORIAN LA English DT Book Review C1 US Air Force Acad, USAF Academy, CO 80840 USA. RP Merzlak, P (reprint author), US Air Force Acad, USAF Academy, CO 80840 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU PHI ALPHA THETA PI ALLENTOWN PA THE HISTORIAN 50 COLLEGE DR, ALLENTOWN, PA 18104-6100 USA SN 0018-2370 J9 HISTORIAN JI Historian PD SPR PY 1999 VL 61 IS 3 BP 725 EP 726 PG 2 WC History SC History GA 218BV UT WOS:000081534100078 ER PT J AU Colle, HA Reid, GB AF Colle, HA Reid, GB TI Double trade-off curves with different cognitive processing combinations: Testing the cancellation axiom of mental workload measurement theory SO HUMAN FACTORS LA English DT Article AB The accomplishment model of average mental workload - a formal axiomatic measurement theory - was used as a basis for developing and testing secondary task indices of mental workload (H. A. Colle & G. B. Reid, 1997). Its cancellation axiom implies global sensitivity, which is an important theoretical and practical criterion for mental workload indices. Performance levels of different secondary tasks were empirically equated in mental workload and then used to test the cancellation axiom. Cognitive processing similarity - including orthographic, phonemic, and semantic processing of pairs of operator and secondary tasks- was manipulated in three experiments. Equivalencies between secondary tasks were independent of secondary-operator task similarity, consistent with the cancellation axiom and the global sensitivity of these secondary tasks. The results suggest that standardized secondary task techniques can be developed for the practical measurement of mental workload. Actual or potential applications of this research include the development of functionally useful and realistic secondary task measures of mental workload. C1 Wright State Univ, Dept Psychol, Dayton, OH 45435 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Colle, HA (reprint author), Wright State Univ, Dept Psychol, Dayton, OH 45435 USA. NR 29 TC 3 Z9 3 U1 0 U2 0 PU HUMAN FACTORS SOC PI SANTA MONICA PA BOX 1369, SANTA MONICA, CA 90406 USA SN 0018-7208 J9 HUM FACTORS JI Hum. Factors PD MAR PY 1999 VL 41 IS 1 BP 35 EP 50 DI 10.1518/001872099779577327 PG 16 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 195VV UT WOS:000080273600004 PM 10354805 ER PT J AU Luke, J Bittorie, JW Cannon, WJ Haldeman, DG AF Luke, J Bittorie, JW Cannon, WJ Haldeman, DG TI Replacement strategy for aging avionics computers SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB With decreasing defense dollars available to purchase new military aircraft, the inventory of existing aircraft will have to last many more years than originally anticipated. As the avionics computers oil these aging aircraft get older, they become more expensive to maintain due to parts obsolescence. In addition, expanding missions and changing requirements lead to growth in the embedded software which, in turn, requires additional processing and memory capacity. Both factors, parts obsolescence and new processing capacity, result in the need to replace the old computer hardware with newer, more capable microprocessor technology. New microprocessors, however, are not compatible with the older computer instruction set architectures. This generally requires the embedded software in these computers to be rewritten. A significant savings - estimated in the billions of dollars - could be achieved in these upgrades if the new computers could execute the old embedded code along with any new code to be added. This paper describes a commercial-off-the-shelf (COTS)-based form, fit, function, and interface ((FI)-I-3) replacement strategy for legacy avionics computers that can reuse existing avionics code "as is" while providing a flexible framework for incremental upgrades and managed change. It is based on a real-time embedded software technology that executes legacy binary code on the latest generation COTS microprocessors. This technology, developed by TRW and being applied under the sponsorship of the Air Force Research Lab (AFRL), promises performance improvements of 5-10 times that of the legacy avionics computer that it replaces. It also promises a 4X decrease in cost and schedule over rewriting the code and provides a "known good" starting point for incremental upgrades of the embedded flight software. Code revalidation cost and risk are minimized since the structure of the embedded code is not changed, allowing the replacement computer to be retested at the "blackbox" level using existing qualification tests. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. TRW, Avion Syst Div, Avion Engn Ctr, Redondo Beach, CA 90278 USA. RP Luke, J (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD MAR PY 1999 VL 14 IS 3 BP 7 EP 11 DI 10.1109/62.750422 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 173WT UT WOS:000079003300002 ER PT J AU Ferens, DV AF Ferens, DV TI The conundrum of software estimation models SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB There are many sophisticated models and methods for estimating the size, cost, and schedule of software projects. However, the ability to accurately estimate software cost, size, or schedule is still dubious. In general, the predictive accuracy of models for estimating software development cost and schedule has not been shown to be better than "within 25 percent of actual cost or schedule, about one half of the time," especially for Department of Defense software efforts. The same is true for software size estimating models and methods, although there are some studies that have shown superior results. For software support (or maintenance) cost estimation, no model has been demonstrated to be accurate. This paper presents a summary of efforts performed to date which demonstrate the accuracy (or lack thereof) of software models. The results of several studies in the areas of software development cost and schedule estimation, size estimation, and support cost estimation are presented to show what these models can and cannot do. Some ideas for improvement are also presented, including the results of some studies which may lead to a resolution of the accuracy conundrum which currently exists. C1 USAF, Res Lab, IFSD, Wright Patterson AFB, OH 45433 USA. RP Ferens, DV (reprint author), USAF, Res Lab, IFSD, 2241 Avion Circle,S1Z19, Wright Patterson AFB, OH 45433 USA. NR 31 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD MAR PY 1999 VL 14 IS 3 BP 23 EP 29 DI 10.1109/62.750425 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 173WT UT WOS:000079003300004 ER PT J AU Young, FCD Houston, JA AF Young, FCD Houston, JA TI Formal verification and legacy redesign SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB Sustaining weapons system hardware and software represents a significant and ever-increasing portion of total system cost. Hardware components are becoming obsolete much sooner while weapons system lifetimes are increasing. We must identify more cost-effective solutions to engineering and reengineering these subsystems. Verifying and validating weapons systems are two of the most costly parts of either engineering process, Traditionally, hardware validation and verification is done by simulation and testing, In the past few years, math- and logic-based formal methods tools have begun to scale up to and be applied successfully to real-world problems. Incorporating formal verification methods into engineering and reengineering processes will cost-effectively and significantly improve the level of trust and the quality of our weapons systems. Formal methods are especially well suited for redesigning current weapon systems which have become unsupportable due to component obsolescence because they help minimize the astronomical costs of rigorously reverifying the reengineered components. We believe that formal methods are an important tool for effective engineering of future weapon systems. C1 USAF, Res Lab, IFTA, Wright Patterson AFB, OH 45433 USA. RP Young, FCD (reprint author), USAF, Res Lab, IFTA, Wright Patterson AFB, OH 45433 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD MAR PY 1999 VL 14 IS 3 BP 31 EP 36 DI 10.1109/62.750426 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 173WT UT WOS:000079003300005 ER PT J AU Chu, J Li, SS Singh, A AF Chu, J Li, SS Singh, A TI Investigation of broad-band quantum-well infrared photodetectors for 8-14-mu m detection SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE broad-band; dark current; InGaAs-GaAs; InGaAs-AlGaAs; long-wavelength infrared; quantum-well infrared photodetectors; responsivity ID EPITAXIAL MULTILAYERS; DEFECTS; DISLOCATIONS; ABSORPTION; WAVELENGTH; STRAIN; HOLE AB Typical quantum-well infrared photodetectors (QWIP's) exhibit a rather narrow spectral bandwidth of 1-2 I'm For certain applications, such as spectroscopy, sensing a broader range of infrared radiation is highly desirable, In this paper, we report the design of four broad-band QWIP's (BB-QWIP's) sensitive over the 8-14-mu m spectral range. Two n-type BB-QWIP's, consisting of three and four quantum wells of different thickness and/or composition in a unit cell which is then repeated 20 times to create the BB-QWIP structure, are demonstrated. The three-well n-type InxGa1-xAs-AlyGa1-yAs BB-QWIP was designed to have a response peak at 10 mu m, with a full-width at half-maximum (FWHM) bandwidth that varies with the applied bias. A maximum bandwidth of Delta lambda/lambda(p) = 21% was obtained for this device at V-b = -2 V. The four-well n-type InxGa1-xAs-GaAs BB-QWIP not only exhibits a large responsivity of 2.31 A/W at 10.3 mu m and V-b = +4.5 V, but also achieves a bandwidth of Delta lambda/lambda(p) = 29% that is broader than the three-well device. In addition, two p-type InxGa1-xAs-GaAs BB-QWIP's with variable well thickness and composition, sensitive in the 7-14-mu m spectral range, are also demonstrated. The variable composition p-type BB-QWIP has a large FWHM bandwidth of Delta lambda/lambda(p) = 48% at T = 40 K and V-b = -1.5 V. The variable thickness p-type BB-QWIP was found to have an even broader FWHM bandwidth of Delta lambda/lambda(p) = 63% at T = 40 K and V-b = 1.1 V, with a corresponding peak responsivity of 25 mA/W at 10.2 mu m. The results show that a broader and flatter spectral bandwidth was obtained in both p-type BB-QWIP's than in the n-type BB-QWIP's under similar operating conditions. C1 Univ Florida, Dept Elect & Comp Engn, Gainesville, FL 32611 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Chu, J (reprint author), Univ Florida, Dept Elect & Comp Engn, Gainesville, FL 32611 USA. NR 20 TC 11 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD MAR PY 1999 VL 35 IS 3 BP 312 EP 319 DI 10.1109/3.748836 PG 8 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 172AM UT WOS:000078899200009 ER PT J AU McGrath, DT Baum, CE AF McGrath, DT Baum, CE TI Scanning and impedance properties of TEM horn arrays for transient radiation SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE antenna arrays; horn antennas; transient radiation ID FINITE-ELEMENT METHOD AB A general concept for ultrawide-band array design using interconnected transverse electromagnetic (TEM) horns is described. At high frequencies (wavelength small compared to unit cell dimensions), the mutual coupling between elements is small and, consequently, the input impedance depends only on the lattice dimensions and not on either scan angle or frequency. At low frequencies (wavelength large compared to unit cell dimensions), the mutual coupling is purposefully made large, by interconnecting the elements to maximize the low-frequency performance. This paper presents the results of analyses using a periodic hybrid finite-element approach to calculate input impedance and scanning performance of generic TEM horn arrays, The limiting case, the planar bicone, is shown to have the frequency-independent property of a self-complementary antenna, making it a useful case for establishing the effects of feed region geometry. Although it radiates bidirectionally, it has the interesting property that its broadside-scan frequency response in the array environment is absolutely Bat up to the grating lobe onset limit. A TEM horn array is more unidirectional, but as a consequence suffers both oscillatory variations in the input impedance with frequency and increased limits on minimum achievable rise time. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP McGrath, DT (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 13 TC 18 Z9 18 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAR PY 1999 VL 47 IS 3 BP 469 EP 473 DI 10.1109/8.768781 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 205FF UT WOS:000080810100008 ER PT J AU Davidovitz, M AF Davidovitz, M TI Perturbation formulas for microstrip patch arrays and elements SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE antennas; microstrip arrays; perturbation methods AB One-term perturbation formulas are derived to characterize periodic microstrip arrays with nonuniform planar distributions of dielectric and magnetic materials. Analogous results are also obtained for single-patch elements. The formulas are generally applicable to other types of antennas. C1 USAF, Res Lab, SNHA, Hanscom AFB, MA 01731 USA. RP Davidovitz, M (reprint author), USAF, Res Lab, SNHA, Hanscom AFB, MA 01731 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAR PY 1999 VL 47 IS 3 BP 536 EP 541 DI 10.1109/8.768789 PG 6 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 205FF UT WOS:000080810100016 ER PT J AU Tomasic, B Hessel, A AF Tomasic, B Hessel, A TI Analysis of finite arrays - A new approach SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE antenna arrays; finite phased arrays AB A novel method for the analysis of finite arrays is presented, The method is based on a global array concept where the array problem (for single-mode elements) is reduced to a solution of a single Fredholm integral equation of the second kind, This formulation offers several types of solutions (not all explored yet) with illuminating results. The approximate solution of this integral equation, for example, yields finite array characteristics in terms of equivalent infinite array scattering parameters and mutual admittances. The method is general, i.e., applicable to any element-type and periodic array geometry. Presently, the method applies to single-mode elements tone unknown per element), however, it can be extended to a multimode analysis. C1 USAF, Res Lab, Electromagnet Technol Directorate, Hanscom AFB, MA 01701 USA. Polytech Univ, Farmingdale, NY 11735 USA. RP Tomasic, B (reprint author), USAF, Res Lab, Electromagnet Technol Directorate, Hanscom AFB, MA 01701 USA. NR 14 TC 13 Z9 13 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAR PY 1999 VL 47 IS 3 BP 555 EP 565 DI 10.1109/8.768792 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 205FF UT WOS:000080810100019 ER PT J AU Santos, E Young, JD AF Santos, E Young, JD TI Probabilistic temporal networks: A unified framework for reasoning with time and uncertainty SO INTERNATIONAL JOURNAL OF APPROXIMATE REASONING LA English DT Article DE temporal reasoning; probabilistic reasoning; abduction; linear constraint satisfaction; cyclicity ID CONSTRAINT AB Complex real-world systems consist of collections of interacting processes/events. These processes change over time in response to both internal and external stimuli as well as to the passage of time itself Many domains such as real-time systems diagnosis, story understanding, and financial forecasting require the capability to model complex systems under a unified framework to deal with both time and uncertainty. Current models for uncertainty and current models for time already provide rich languages to capture uncertainty and temporal information, respectively. Unfortunately, these semantics have made it extremely difficult to unify time and uncertainty in a way which cleanly and adequately models the problem domains at hand. Existing approaches suffer from significant trade offs between strong semantics for uncertainty and strong semantics for time. In this paper, we explore a new model, the Probabilistic Temporal Network (PTN), for representing temporal and atemporal information while fully embracing probabilistic semantics. The model allows representation of time constrained causality, of when and if events occur, and of the periodic and recurrent nature of processes. (C) 1999 Elsevier Science Inc. All rights reserved. C1 Univ Connecticut, Dept Comp Sci & Engn, Storrs, CT 06269 USA. USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Univ Connecticut, Dept Comp Sci & Engn, Storrs, CT 06269 USA. EM eugene@engr.uconn.edu NR 38 TC 22 Z9 23 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0888-613X EI 1873-4731 J9 INT J APPROX REASON JI Int. J. Approx. Reasoning PD MAR PY 1999 VL 20 IS 3 BP 263 EP 291 DI 10.1016/S0888-613X(99)00009-2 PG 29 WC Computer Science, Artificial Intelligence SC Computer Science GA 190VK UT WOS:000079985800005 ER PT J AU Calcaterra, JR Mall, S AF Calcaterra, JR Mall, S TI Strength degradation during fatigue of unidirectional and cross-ply SCS-6/Ti-15-3 composites SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Article ID TITANIUM MATRIX COMPOSITES; FAILURE MECHANISMS; CRACK GROWTH AB The majority of previous fatigue studies on Titanium Matrix Composites (TMCs) have investigated fatigue life where specimens are cycled until failure. Although fatigue life is very important to designers, it is not the only cycle-dependent criterion used to characterize the material. Another behavior required to evaluate the material is the residual strength degradation due to cyclic loading. To date, very few investigations have been completed to determine this behavior in TMCs. Of those investigations, none has explicitly determined the dependence of residual strength reduction on laminate orientation. To study this, the residual strength behaviors of SCS-6/Ti-15-3 with laminate orientations of [0], and [0/90](2s) were investigated after being fatigued at 427 degrees C with different frequencies, R-ratios and control modes. Results show that residual strength degradation is primarily dependent on laminate orientation and percent of cyclic life. Different test parameters mainly affect residual strength degradation through the corresponding changes in cyclic life. Micromechanical analysis reveals that the laminate dependence is due to differences in damage morphologies and there is no single parameter, such as axial fiber stress, that can correlate all the residual strength data from the different fatigue conditions. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Inst Technol, Res Lab MLLN, AFIT,ENY, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, Inst Technol, Res Lab MLLN, AFIT,ENY, Bldg 640,2950 P St, Wright Patterson AFB, OH 45433 USA. NR 20 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD MAR PY 1999 VL 21 IS 3 BP 215 EP 223 DI 10.1016/S0142-1123(98)00068-1 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 177CA UT WOS:000079188800001 ER PT J AU Langan, KJ Samuels, JJ AF Langan, KJ Samuels, JJ TI Wing jet blowing on the subsonic high alpha research concept fighter configuration SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 35th Aerospace Science Meeting / Nonlinear Dynamical Systems Symposium CY JAN 06-10, 1997 CL RENO, NEVADA SP Amer Inst Aeronaut & Astronaut, USAF, Off Sci Res, Sandia Natl Labs AB A large-scale experimental investigation using the 55%-scale Subsonic High Alpha Research Concept (SHARC) was performed in the NASA Ames Research Center 40- by 80-ft Wind Tunnel. The SHARC configuration represents an advanced low-observable fighter aircraft, and features a clipped diamond wing with leading- and trailing-edge sweep angles of +/-40 deg, a chined forebody, leading-edge extensions, and a vee-tail. Data covering the angle of attack range from -4 deg to +42.4 deg, and sideslip angles ranging from -10 deg to +10 deg were acquired at a dynamic pressure of 40 psf. Test data are presented for symmetric and asymmetric wing jet nozzle blowing. Blowing coefficient values ranged from a minimum of 0.005 to a maximum of 0.020. The results indicate that wing jet nozzle blowing is an effective lift-enhancement device, giving an across-the-board net increase in lift over the entire angle-of-attack range tested. The jets were also found to improve the aircraft's drag polar. Roll control using asymmetric jet blowing equaled or exceeded that available via the deflection of only a single aileron. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Langan, KJ (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 12 TC 0 Z9 0 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAR-APR PY 1999 VL 36 IS 2 BP 413 EP 420 DI 10.2514/2.2446 PG 8 WC Engineering, Aerospace SC Engineering GA 184LT UT WOS:000079614200012 ER PT J AU Morton, SA Beran, PS AF Morton, SA Beran, PS TI Hopf-bifurcation analysis of airfoil flutter at transonic speeds SO JOURNAL OF AIRCRAFT LA English DT Article AB Hopf-bifurcation analysis is used to determine flutter onset for a pitch-and-plunge airfoil at transonic Mach number conditions. The pitch-and-plunge model is a coupling of the Euler equations and a two-degree-of-freedom structural model composed of linear and torsional springs. The Euler equations are discretized using the upwind total variation diminishing scheme of Harten and Yee. Equilibrium solutions of the aeroelastic model are computed using Newton's method, and dynamic solutions are explicitly integrated in time with first-order accuracy. The Hopf-bifurcation point, which models the putter condition, is computed directly using a modified form of the Griewank and Reddien algorithm. A path of Hopf points is computed as a function of Mach number to produce a Mach putter boundary. The flutter boundary is validated by time integration, Flutter boundaries are also obtained through variation of static pretwist and pitch and plunge damping. The direct, Hopf-point method is found to be precise and efficient for grids typical of inviscid, transonic airfoil calculations. C1 USAF, Wright Patterson AFB, OH 45433 USA. USAF Acad, Dept Aeronaut, HQ USAFA DFAN, Colorado Springs, CO 80840 USA. RP Morton, SA (reprint author), USAF Acad, Dept Aeronaut, HQ USAFA DFAN, 2354 Fairchild Dr,Suite 6H22, Colorado Springs, CO 80840 USA. NR 15 TC 38 Z9 38 U1 0 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAR-APR PY 1999 VL 36 IS 2 BP 421 EP 429 DI 10.2514/2.2447 PG 9 WC Engineering, Aerospace SC Engineering GA 184LT UT WOS:000079614200013 ER PT J AU Tromp, JC AF Tromp, JC TI Flowfield simulation about a 65-degree delta wing during constant roll-rate motions SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA Atmospheric Flight Mechanics Conference CY AUG 10-12, 1998 CL BOSTON, MASSACHUSETTS SP AIAA C1 USAF, VAAC, Wright Patterson AFB, OH 45433 USA. RP Tromp, JC (reprint author), USAF, VAAC, Bldg 146,2210 8th St,Suite 11, Wright Patterson AFB, OH 45433 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAR-APR PY 1999 VL 36 IS 2 BP 486 EP 488 DI 10.2514/2.2462 PG 3 WC Engineering, Aerospace SC Engineering GA 184LT UT WOS:000079614200027 ER PT J AU Liu, HC Szmulowicz, F Wasilewski, ZR Buchanan, M Brown, GJ AF Liu, HC Szmulowicz, F Wasilewski, ZR Buchanan, M Brown, GJ TI Intersubband infrared detector with optimized valence band quantum wells for 3-5 mu m wavelength region SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID BACKGROUND LIMITED PERFORMANCE; UPPER STATE POSITION; DARK CURRENT; ABSORPTION; PHOTODETECTORS; DEPENDENCE AB We present results on a p-type intersubband infrared detector for the 3-5 mu m wavelength region with optimal quantum well design. For valence band quantum wells made by the AlGaAs/GaAs heterosystem with negligible strain, the ground state subband is the first heavy hole subband, and a structure with the second light hole subband in resonance with the top of the barrier is optimal for normal incidence. Using this resonance design, the fabricated detector shows good performance with a background limited operating temperature of 100 K. Our experiments also show a clear polarization dependence for different intersubband transitions involving heavy hole to heavy hole and heavy hole to light hole processes. [S0021-8979(99)07504-0]. C1 Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0R6, Canada. USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0R6, Canada. EM h.c.liu@nrc.ca NR 21 TC 27 Z9 28 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 1 PY 1999 VL 85 IS 5 BP 2972 EP 2976 DI 10.1063/1.369062 PG 5 WC Physics, Applied SC Physics GA 169YH UT WOS:000078777000076 ER PT J AU Schenzle, A Lenke, H Spain, JC Knackmuss, HJ AF Schenzle, A Lenke, H Spain, JC Knackmuss, HJ TI 3-hydroxylaminophenol mutase from Ralstonia eutropha JMP134 catalyzes a Bamberger rearrangement SO JOURNAL OF BACTERIOLOGY LA English DT Article ID ENCODING GLUTAMINE-SYNTHETASE; NITROAROMATIC COMPOUNDS; NUCLEOTIDE-SEQUENCE; MICROBIAL-DEGRADATION; INITIAL HYDROGENATION; REDUCTION; GENE; GLNA; ACID; BINDING AB 3-Hydroxylaminophenol mutase from Ralstonia eutropha JMP134 is involved in the degradative pathway of 3-nitrophenol, in which it catalyzes the conversion of 3-hydroxylaminophenol to aminohydroquinone. To show that the reaction was really catalyzed by a single enzyme without the release of intermediates, the corresponding protein was purified to apparent homogeneity from an extract of cells grown on 3-nitrophenol as the nitrogen source and succinate as the carbon and energy source. 3-Hydroxylaminophenol mutase appears to be a relatively hydrophobic but soluble and colorless protein consisting of a single 62-kDa polypeptide. The pi was determined to be at pH 4.5. In a database search, the NH(2)-terminal amino acid sequence of the undigested protein and of two internal sequences of 3-hydroxylaminophenol mutase were found to be most similar to those of glutamine synthetases from different species. Hydroxylaminobenzene, 4-hydroxylaminotoluene, and 2-chloro-5-hydroxylaminophenol, but not 4-hydroxylaminobenzoate, can also serve as substrates for the enzyme. The enzyme requires no oxygen or added cofactors for its reaction, which suggests an enzymatic mechanism analogous to the acid-catalyzed Bamberger rearrangement. C1 Univ Stuttgart, Inst Mikrobiol, D-70569 Stuttgart, Germany. Univ Stuttgart, Fraunhofer Inst Grenzflachen & Bioverfahrenstech, D-70569 Stuttgart, Germany. Armstrong Lab, AFRL, MRLQ, Tyndall AFB, FL 32403 USA. RP Knackmuss, HJ (reprint author), Univ Stuttgart, Inst Mikrobiol, Allmandring 31, D-70569 Stuttgart, Germany. EM imbhjk@po.uni-stuttgart.de NR 55 TC 20 Z9 24 U1 1 U2 5 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD MAR PY 1999 VL 181 IS 5 BP 1444 EP 1450 PG 7 WC Microbiology SC Microbiology GA 170XW UT WOS:000078833200010 PM 10049374 ER PT J AU Hicks, BW AF Hicks, BW TI Recombinant green fluorescent protein isoforms: Exercises to integrate molecular biology, biochemistry and biophysical chemistry SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article ID UNDERGRADUATE BIOCHEMISTRY; GENE-EXPRESSION; CODON USAGE; IN-VIVO; CELLS; CHROMOPHORE; MARKER; PURIFICATION; LOCALIZATION; INDICATORS C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. RP Hicks, BW (reprint author), USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. NR 64 TC 8 Z9 8 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD MAR PY 1999 VL 76 IS 3 BP 409 EP 415 PG 7 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA 168FF UT WOS:000078680400039 ER PT J AU Chiu, YH Dressler, RA Levandier, DJ Williams, S Murad, E AF Chiu, YH Dressler, RA Levandier, DJ Williams, S Murad, E TI Guided-ion beam study of the O-2(+)+C2H2 charge-transfer and chemical reaction channels SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ENERGY DISPOSAL; DYNAMICS; METHANE; C2H2+; SCATTERING; COLLISIONS AB Guided-ion beam cross section and product ion time-of-flight (TOF) measurements are presented for the O-2(+)((2)Pi(g)) + C2H2 reaction over the center-of-mass collision energy range of 0.05-12 eV. The reaction exhibits a strong charge-transfer (CT) channel and several weak chemical reaction channels leading to the following product ions: C2H2O+, CH2+, COH+/HCO+, CO+, CH+, and C+. The magnitude of the charge-transfer cross section is comparable to the capture cross section at low collision energies. The charge-transfer products are characterized predominantly by a direct, long-range mechanism that is accompanied by smaller impact parameter collisions involving longer-lived complexes, whose lifetimes are several times shorter than the complex rotational period. The TOF analysis indicates that the complexes also decay to chemical reaction products at higher energies. A density functional survey of intermediates is conducted. The chemical reaction products are postulated to be formed via an endothermic transition state associated with a H2CCO2+ intermediate. (C) 1999 American Institute of Physics. [S0021-9606(99)00309-8]. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP USAF, Res Lab, Space Vehicles Directorate, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. EM YH_CHIU@hotmail.com NR 32 TC 4 Z9 4 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 1 PY 1999 VL 110 IS 9 BP 4291 EP 4299 DI 10.1063/1.478312 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 168HP UT WOS:000078686400023 ER PT J AU Roberts, TM AF Roberts, TM TI Time-domain deconvolution removes the effects of near-field scatterers SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE time-domain; deconvolution; near-field; scattering; diffraction; Volterra; pulse; antenna; interference; FDTD; finite difference; electromagnetic; compute; numerical; transients ID SCHEMES AB This paper studies deconvolution algorithms for removing the interference caused by objects near an antenna. Infinitely many time-domain algorithms are considered, the best of which may compete with frequency-domain methods. Special care is taken to find a stable deconvolution algorithm that also accommodates the discontinuity-related numerical noise in standard finite-difference time-domain data. C1 USAF, Res Lab, SNHA, Hanscom AFB, MA 01731 USA. RP Roberts, TM (reprint author), USAF, Res Lab, SNHA, 31 Grenier St, Hanscom AFB, MA 01731 USA. EM tmr@zippy.rl.plh.af.mil NR 14 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD MAR 1 PY 1999 VL 149 IS 2 BP 293 EP 305 DI 10.1006/jcph.1998.6154 PG 13 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 171MT UT WOS:000078868300005 ER PT J AU Singh, NB Suhre, DR Rosch, W Meyer, R Marable, M Fernelius, NC Hopkins, FK Zelmon, DE Narayanan, R AF Singh, NB Suhre, DR Rosch, W Meyer, R Marable, M Fernelius, NC Hopkins, FK Zelmon, DE Narayanan, R TI Modified GaSe crystals for mid-IR applications SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 12th International Conference on Crystal Growth, held in Conjunction with the 10th International Conference on Vapor Growth and Epitaxy (ICCG-12/ICVGE-10) CY JUL 26-31, 1998 CL JERUSALEM, ISRAEL DE nonlinear; gallium selenide; second harmonic; solid-solution; Bridgman ID SELENIDE CRYSTALS; GROWTH AB We have synthesized stoichiometric batches of GaSe by reacting mixtures of the parent components and have grown centimeter-size modified single crystals of GaSe by the vertical Bridgman technique. GaSe crystals doped with silver, indium and silver gallium selenide were fabricated for wavelength conversion. Silver doping produced scattering centers which could be dissolved by annealing at temperatures above 700 degrees C. Crystals cracked extensively during the annealing process and optical quality deteriorated. SHG measurements of In-doped crystals showed a "d" value of 49 pm/V for low concentration In-doped GaSe crystals. The silver gallium selenide doped GaSe crystals showed a "d" value of 75 pm/V which resulted in significant increase in the "d(2)/n(3)". (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Northrop Grumman Corp, ESSD, STC, Pittsburgh, PA 15235 USA. Northrop Grumman Corp, ESID, Rolling Meadows, IL 60001 USA. USAF, Res Lab, Mat Directorate, WL,MLPO, Wright Patterson AFB, OH 45433 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. RP Singh, NB (reprint author), Northrop Grumman Corp, ESSD, STC, 1350 Beulah Rd, Pittsburgh, PA 15235 USA. EM singh.n.b@postal.essd.northgrum.com NR 5 TC 43 Z9 45 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR PY 1999 VL 198 BP 588 EP 592 DI 10.1016/S0022-0248(98)01214-7 PN 1 PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 187ZM UT WOS:000079819000108 ER PT J AU Chen, QS Prasad, V Chatterjee, A Larkin, J AF Chen, QS Prasad, V Chatterjee, A Larkin, J TI A porous media-based transport model for hydrothermal growth SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 12th International Conference on Crystal Growth, held in Conjunction with the 10th International Conference on Vapor Growth and Epitaxy (ICCG-12/ICVGE-10) CY JUL 26-31, 1998 CL JERUSALEM, ISRAEL DE hydrothermal synthesis; crystal growth; porous media; process modeling AB A hydrothermal crystal growth system usually consists of a porous bed of polycrystalline charge, predetermined volume of a solvent, suitably oriented seeds, etc. For preliminary study of flow and heat transfer, the convective system for hydrothermal growth can be considered as a composite fluid and porous layer and the flow in the nutrient bed can be modeled using the Darcy-Brinkman-Forchheimer formulation. A three-dimensional algorithm has been developed to examine the flow and heat transfer in a typical autoclave system, which is partially heated on the vertical wall and adiabatic at the top and bottom. The study presents, for the first time, a transport model for hydrothermal growth and the possible flow structure in an autoclave. The temperature and flow fields are analyzed for a few selected cases. (C) 1999 Elsevier Science B.V. All rights reserved. C1 SUNY Stony Brook, Consortium Crystal Growth Res, Stony Brook, NY 11794 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Prasad, V (reprint author), SUNY Stony Brook, Consortium Crystal Growth Res, Stony Brook, NY 11794 USA. EM prasad@pml.eng.sunysb.edu NR 7 TC 22 Z9 23 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAR PY 1999 VL 198 BP 710 EP 715 DI 10.1016/S0022-0248(98)01191-9 PN 1 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 187ZM UT WOS:000079819000129 ER PT J AU Smith, SR Evwaraye, AO Mitchel, WC Capano, MA AF Smith, SR Evwaraye, AO Mitchel, WC Capano, MA TI Shallow acceptor levels in 4H- and 6H-SiC SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 40th Electronic Materials Conference (EMC-40) CY JUN 24-26, 1998 CL UNIV VIRGINIA, CHARLOTTESVILLE, VIRGINIA SP TMS HO UNIV VIRGINIA DE acceptor ionization levels; doping; silicon carbide (SiC) ID ADMITTANCE SPECTROSCOPY; NITROGEN DONORS; 6H-SILICON CARBIDE; BORON ACCEPTOR AB Shallow impurities are the principal means of affecting the electrical properties of semiconductors in order to induce desired characteristics. They can be used to isolate a region by introducing carriers of opposite charge, or they can be used to enhance the number of carriers of a particular type. Thermal admittance spectroscopy has been used to determine the activation energies of the principal p-type dopants, Al and B, in 4H and 6H-SiC, and temperature dependent Hall effect measurements were used to study the shallow B accepters in 6H-SiC. The acceptor species B and Al occupy inequivalent lattice sites in the Si sublattice, and would be expected to exhibit distinct energy levels for each site in analogy to the well known donor energy levels of N. Activation energies for B in 6H-SiC were found to be E-h = E-v + 0.27 eV, E-k1 = E-v + 0.31 eV, and E-k2 = E-v + 0.38 eV. Al accepters in 4H-SiC were found to-exhibit-two energy levels at E-h = E-v + 0.212 eV and E-k = E-v +0.266 eV. C1 USAF, Res Lab, Mat Directirate, AFRL,MLPO, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. Univ Dayton, Dept Phys, Dayton, OH 45469 USA. RP Smith, SR (reprint author), USAF, Res Lab, Mat Directirate, AFRL,MLPO, Wright Patterson AFB, OH 45433 USA. NR 24 TC 16 Z9 18 U1 1 U2 6 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAR PY 1999 VL 28 IS 3 BP 190 EP 195 DI 10.1007/s11664-999-0012-3 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 177ZB UT WOS:000079240000012 ER PT J AU Capano, MA Ryu, S Cooper, JA Melloch, MR Rottner, K Karlsson, S Nordell, N Powell, A Walker, DE AF Capano, MA Ryu, S Cooper, JA Melloch, MR Rottner, K Karlsson, S Nordell, N Powell, A Walker, DE TI Surface roughening in ion implanted 4H-silicon carbide SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 40th Electronic Materials Conference (EMC-40) CY JUN 24-26, 1998 CL UNIV VIRGINIA, CHARLOTTESVILLE, VIRGINIA SP TMS HO UNIV VIRGINIA DE annealing ambient; ion implantation; silicon carbide (SiC); surface morphology ID EPILAYERS; N+ AB Silicon carbide (SiC) devices have the potential to yield new components with functional capabilities that far exceed components based on silicon devices. Selective doping of SiC by ion implantation is an important fabrication technology that-must be completely understood if SiC devices are to achieve their potential. One major problem with ion implantation into SiC is the surface roughening that results from annealing SiC at the high temperatures which are needed to activate implanted acceptor ions, boron or aluminum. This paper examines the causes and possible solutions to surface roughening of implanted and annealed 4H-SiC. Samples consisting of n-type epilayers (5 x 10(15) cm(-3), 4 mu m thick) on 4H-SiC substrates were implanted with B or Al to a total dose of 4 x 10(14) cm(-2) or 2 x 10(15) cm(-2), respectively. Roughness measurements were made using atomic force microscopy. From the variation of root mean square (rms) roughness with annealing temperature, apparent activation energies for roughening following implantation with Al and B were 1.1 and 2.2 eV, respectively, when annealed in argon. Time-dependent activation and surface morphology analyses show a sublinear dependence of implant-activation on time; activation percentages after a 5 min anneal following boron implantation are about a factor of two less than after a 40 min anneal. The rms surface roughness remained relatively constant-with time for anneals in argon at 1750 degrees C. Roughness values at this temperature were approximately 8.0 nm. Annealing experiments performed in different ambients demonstrated the benefits of using silane to maintain good surface morphology. Roughnesses were 1.0 nn (rms) when boron or aluminum implants were annealed in silane at 1100 degrees C, but were about 8 and 11 nm for B and Al, respectively, when annealed in argon at the same temperature. C1 Purdue Univ, W Lafayette, IN 47907 USA. IMC, Electrum 233, S-16440 Stockholm, Sweden. Epitronics, Danbury, CT USA. USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Capano, MA (reprint author), Purdue Univ, W Lafayette, IN 47907 USA. RI Nordell, Nils/C-6615-2015 OI Nordell, Nils/0000-0002-4148-5679 NR 9 TC 81 Z9 83 U1 1 U2 18 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAR PY 1999 VL 28 IS 3 BP 214 EP 218 DI 10.1007/s11664-999-0016-z PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 177ZB UT WOS:000079240000016 ER PT J AU Mauger, MJ Waite, RM Alexander, JB Schindler, WG AF Mauger, MJ Waite, RM Alexander, JB Schindler, WG TI Ideal endodontic access in mandibular incisors SO JOURNAL OF ENDODONTICS LA English DT Article AB Straight-line access in mandibular incisors facilitates locating and debridement of the canals. The purpose of this study was to plot where ideal access should be located in mandibular incisors to obtain straight-line access to the apical third of the root canal and to determine if a correlation exists between incisal edge wear and position of access opening. Two hundred and seventy-nine mandibular incisors were radiographed in clinical and proximal views. Straight-line access was determined by finding midpoints in the canal at two levels and extending a line connecting the points through the crown. Teeth were graded as to the condition of the incisal edge. Ideal straight-line access was determined to be at the incisal edge in 72.4% of the teeth, whereas in 27.6% of the teeth it was to the facial of the incisal edge. As the wear of the incisal edge increased, the ideal access moved from the facial toward the incisal. C1 Univ Texas, Hlth Sci Ctr, Dept Endodont, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, Dept Endodont, Lackland AFB, TX 78236 USA. RP Schindler, WG (reprint author), Univ Texas, Hlth Sci Ctr, Dept Endodont, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. NR 5 TC 5 Z9 9 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0099-2399 J9 J ENDODONT JI J. Endod. PD MAR PY 1999 VL 25 IS 3 BP 206 EP 207 DI 10.1016/S0099-2399(99)80143-5 PG 2 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 172BY UT WOS:000078903500013 PM 10321188 ER PT J AU Forbes, JM Palo, SE Marcos, FA AF Forbes, JM Palo, SE Marcos, FA TI Longitudinal structures in lower thermosphere density SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETIC STORM; MODEL; IONOSPHERE; MESOSPHERE; DYNAMICS; WINDS; WAVES AB Thermospheric densities near 200 km from the Satellite Electrostatic Triaxial Accelerometer (SETA) experiment during July and December 1983 are analyzed to reveal two types of longitude structures: (1) the so-called "longitude/UT" variation which has been noted in higher-altitude satellite data and incorporated into the mass spectrometer incoherent scatter extension-90 (MSISE-90) empirical model [Hedin, 1991] and (2) "higher-order structures" in the form of longitudinal wave patterns which have not previously been mentioned in the thermosphere-ionosphere literature. The longitude/UT variation in the SETA densities shares many similarities with that embodied in the MSISE-90 model, except for some differences in symmetry about the equator. Interpretation concerning the origin of the observed variation is handicapped by the Sun-synchronous limitations of the satellite orbit and by the convolution of high-latitude heating effects being mapped into the geographic frame while solar-driven latitudinal variations are mapped into the geomagnetic frame. An unambiguous separation of these effects is not possible with the present orbital constraints. The space-time Fourier analysis method of Salby [1982a, b] is applied in an attempt to quantitatively characterize the higher-order structure in the data. The nature of the satellite sampling introduces ambiguities into the determination of zonal wavenumbers and periodicities. There is evidence of s = 1 and s = 2 stationary features, eastward propagating Kelvin waves, and a number of westward propagating waves with zonal wavenumbers s = 0 to s = 6 and periods between 6 and 10 hours. Meyer ann Forbes [1997] have recently shown the latter class of waves, referred to as Lamb waves in an isothermal nondissipative atmosphere, to represent the preferred response to broadband forcing of the thermosphere. The present observations may represent the existence of Lamb waves in the thermosphere. C1 Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Forbes, JM (reprint author), Univ Colorado, Dept Aerosp Engn Sci, Boulder, CO 80309 USA. OI FORBES, JEFFREY/0000-0001-6937-0796 NR 20 TC 12 Z9 12 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 1999 VL 104 IS A3 BP 4373 EP 4385 DI 10.1029/1998JA900036 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 171NK UT WOS:000078870000012 ER PT J AU Cliver, EW AF Cliver, EW TI Comment on "Origin of coronal and interplanetary shocks: A new look with Wind spacecraft data" by N. Gopalswamy et al. SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Editorial Material ID MASS EJECTIONS; II BURSTS; RADIO-EMISSION; SOLAR-FLARES; ACCELERATION; TRANSIENTS; SPECTRA; SPRAYS; EVENTS C1 USAF, Res Lab, AFRL VSBS, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Cliver, EW (reprint author), USAF, Res Lab, AFRL VSBS, Space Vehicles Directorate, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. EM cliver@plh.af.mil NR 40 TC 17 Z9 18 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 1999 VL 104 IS A3 BP 4743 EP 4747 DI 10.1029/98JA02828 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 171NK UT WOS:000078870000044 ER PT J AU Gopalswamy, N Kaiser, ML Lepping, RP Berdichevsky, D Ogilvie, K Kahler, SW Kondo, T Isobe, T Akioka, M AF Gopalswamy, N Kaiser, ML Lepping, RP Berdichevsky, D Ogilvie, K Kahler, SW Kondo, T Isobe, T Akioka, M TI Comment on "Origin of coronal and interplanetary shocks: A new look with Wind spacecraft data" by N. Gopalswamy et al. - Reply SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Editorial Material ID MASS EJECTIONS; II BURSTS; EVENTS; FLARES C1 NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Raytheon STX, Greenbelt, MD USA. USAF, Res Lab, VSBS, Hanscom AFB, MA 01731 USA. Commun Res Lab, Ibaraki, Osaka, Japan. RP Gopalswamy, N (reprint author), NASA, Goddard Space Flight Ctr, Code 682-3,Bldg 26,Room G-1, Greenbelt, MD 20771 USA. RI Gopalswamy, Nat/D-3659-2012 NR 24 TC 16 Z9 16 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD MAR 1 PY 1999 VL 104 IS A3 BP 4749 EP 4754 DI 10.1029/98JA02832 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 171NK UT WOS:000078870000045 ER PT J AU Warner, MS Hodges, DH AF Warner, MS Hodges, DH TI Treatment of control constraints in finite element solution of optimal control problems SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article C1 Georgia Inst Technol, Sch Aerosp Engn, Atlanta, GA 30332 USA. RP Warner, MS (reprint author), USAF, Natl Air Intelligence Ctr, Data Exploitat Directorate, Wright Patterson AFB, OH 45433 USA. NR 4 TC 6 Z9 6 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAR-APR PY 1999 VL 22 IS 2 BP 358 EP 360 DI 10.2514/2.4386 PG 3 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 175PZ UT WOS:000079104700021 ER PT J AU Franklin, RE Perram, GP AF Franklin, RE Perram, GP TI Laser excitation spectra and Franck-Condon factors for Bi2X1 Sigma(+)(g)-> A(0(u)(+)) SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID X BAND SYSTEM; ELECTRONIC STATES; BI-2; BI2; FLUORESCENCE; CONSTANTS; BISMUTH AB Laser excitation spectra of the lowest vibrational levels, nu(n) = 2-5 and nu' = 0-4, for the Bi-2 X(1)Sigma(g)(+) --> A(0(u)(+)) system have been recorded for a wide range of rotational levels, 0 < J < 211, at Doppler-limited resolution of 0.013 cm(-1). New rotational term values and spectroscopic constants are reported, improving the accuracy of predicted line positions for high rotational levels by as much as 0.8 cm(-1). In addition, Franck-Condon factors are computed and compared with experimental observations from CW laser-induced fluorescence spectra. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Franklin, RE (reprint author), USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. NR 16 TC 6 Z9 6 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD MAR PY 1999 VL 194 IS 1 BP 1 EP 7 DI 10.1006/jmsp.1998.7769 PG 7 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 166NV UT WOS:000078584000001 ER PT J AU Boyan, BD Caplan, AI Heckman, JD Lennon, DP Ehler, W Schwartz, Z AF Boyan, BD Caplan, AI Heckman, JD Lennon, DP Ehler, W Schwartz, Z TI Osteochondral progenitor cells in acute and chronic canine nonunions SO JOURNAL OF ORTHOPAEDIC RESEARCH LA English DT Article ID MESENCHYMAL STEM-CELLS; GROWTH-FACTOR-BETA; BONE MORPHOGENETIC PROTEIN; IN-VITRO; ALKALINE-PHOSPHATASE; OSTEOGENIC CELLS; MARROW; DIFFERENTIATION; CHONDROCYTES; EXPRESSION AB This study examined the ability of cells isolated from early healing segmental defects and from tissue from chronic nonunions to support bone and cartilage formation In vivo and their response to transforming growth factor-betal in vitro. Ostectomies (3 mm) were created in the radial diaphysis of four dogs. The dogs were splinted 3-5 days postoperatively and then allowed to bear full weight. At 7 days, tissue in the defect was removed and any periosteum was discarded; cells in the defect tissue were released by enzymatic digestion. The dogs were splinted again and allowed to bear full weight for 12 weeks. Radiographs confirmed a persistent nonunion in each dog. Defect tissue was again removed, any periosteum was discarded, and cells were isolated. Cells were also obtained from the defect tissue by nonenzymatic means with use of explant cultures. One-half of the tissue and one-half of any preconfluent, first-passage cultures were shipped to Cleveland by overnight carrier. At second passage, cells were loaded into ceramic cubes and implanted into immunocompromised mice for 3 or 6 weeks. Harvested cubes were examined histologically for cartilage and bone with use of a semiquantitative scoring system. Confluent fourth-passage cultures of 7 and 84-day defect tissue cells were cultured with 0.03-0.88 ng/ml transforming growth factor-betal for 24 hours, and [H-3]thymi dine incorporation and alkaline phosphatase specific activity were determined. Donor-dependent differences were noted in the rate at which defect cells achieved confluence; in general, cells from 7-day tissue divided most rapidly. Seven-day defect cells formed less bone and at a slower rate than was seen in the ceramic cubes containing samples from day 84. Cells derived enzymatically behaved similarly to those from explant cultures. Ceramic cubes contained fibrous connective tissue, cartilage, bone, and fat, indicating that multipotent cells were present, Stimulation of [H-3]thymidine incorporation in response to transforming growth factor-betal was donor dependent and variable; only two of six separate isolates of cells exposed to it had measurable alkaline phosphatase activity (which was relatively low), and none of the cultures exhibited an increase in response to transforming growth factor-betal for 24 hours. This indicates that mesenchymal progenitor cells are present in the healing defect tissue at 7 and 84 days and that the relative proportion of osteochondroprogenitor cells is greater at the later time. The response to transforming growth factor-betal is typical of multipotent mesenchymal cells but not of committed chondrocytes or osteoblasts, indicating that these committed and differentiated cells are not present in early stages of healing and suggesting that their differentiation is inhibited in chronic nonunion. C1 Univ Texas, Hlth Sci Ctr, Dept Orthopaed, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Biochem, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Periodont, San Antonio, TX 78284 USA. Case Western Reserve Univ, Skeletal Res Inst, Cleveland, OH 44106 USA. Audie L Murphy Mem Vet Hosp, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Hebrew Univ Jerusalem, Hadassah Fac Dent Med, Jerusalem, Israel. RP Boyan, BD (reprint author), Univ Texas, Hlth Sci Ctr, Dept Orthopaed, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. FU NIDCR NIH HHS [DE-07220, DE-08603] NR 64 TC 33 Z9 35 U1 0 U2 0 PU JOURNAL BONE JOINT SURGERY INC PI NEEDHAM PA 20 PICKERING ST, NEEDHAM, MA 02192 USA SN 0736-0266 J9 J ORTHOPAED RES JI J. Orthop. Res. PD MAR PY 1999 VL 17 IS 2 BP 246 EP 255 DI 10.1002/jor.1100170214 PG 10 WC Orthopedics SC Orthopedics GA 188GM UT WOS:000079838500013 PM 10221842 ER PT J AU Heiser, WH AF Heiser, WH TI Comment on "off-design performance prediction of single-spool turbojets using gasdynamics" SO JOURNAL OF PROPULSION AND POWER LA English DT Editorial Material C1 USAF Acad, Dept Aeronaut, Colorado Springs, CO 80840 USA. RP Heiser, WH (reprint author), USAF Acad, Dept Aeronaut, POB 428, Colorado Springs, CO 80840 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 1999 VL 15 IS 2 BP 368 EP 368 PG 1 WC Engineering, Aerospace SC Engineering GA 176QN UT WOS:000079163400030 ER PT J AU Metzler, KT Woody, RD Miller, AW Miller, BH AF Metzler, KT Woody, RD Miller, AW Miller, BH TI In vitro investigation of the wear of human enamel by dental porcelain SO JOURNAL OF PROSTHETIC DENTISTRY LA English DT Article ID RESTORATIVE MATERIALS; TOOTH WEAR; PROSTHODONTIC MATERIALS; FELDSPATHIC PORCELAIN; POLISHED PORCELAIN; FLEXURAL STRENGTH; SURFACE-ROUGHNESS; OCCLUSAL WEAR; CERAMICS; GOLD AB Statement of problem. Metal ceramic systems are advocated when both esthetics and strength are required. A major drawback to many porcelains is their wear and destruction of opposing natural dentition. Purpose. This study evaluated the wear of enamel opposing 1 traditional and 2 recently introduced low-fusing feldspathic dental porcelains. Material and methods. Six blocks of Ceramco II, Finesse, and Omega 900 feldspathic porcelain materials were fabricated and fired according to manufacturer recommendations. Porcelain blocks were polished through 0.25 mu m diamond polishing paste. Thirty-six enamel specimens were obtained and milled to a 2 mm (+0.5 mm) diameter. Enamel specimens were attached to an offset cam motor operating at 60 Hz. Enamel specimens were in constant contact with the stationary porcelain blocks under a load of 600 g and traversed a distance of 8 mm. Diameter and height of enamel specimens were measured at times of 0, 6, 12, 24, and 48 hours and subsequent determination of enamel volume loss recorded. Profilometric surface roughness of the ceramic blocks was also measured for the corresponding times. Results. Statistical analysis revealed that both Finesse and Omega 900 feldspathic porcelains caused significantly less enamel volume loss when compared with Ceramco II porcelain at all time intervals. Surface roughness revealed no consistent significant differences among porcelains. Conclusion. Both Finesse and Omega 900 porcelains were not as destructive to human tooth structure as Ceramco II porcelain. These results suggest an advantage of the new, lower-fusing porcelains in conditions where natural dentition wear is a concern. C1 Texas A&M Univ Syst, Baylor Coll Dent, Dept Restorat Sci, Dallas, TX USA. Texas A&M Univ Syst, Baylor Coll Dent, Dept Biomat Sci, Dallas, TX USA. RP Metzler, KT (reprint author), 5th Dent Flight, 10 Missile Ave, Minot AFB, ND 58705 USA. NR 74 TC 49 Z9 52 U1 2 U2 2 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0022-3913 J9 J PROSTHET DENT JI J. Prosthet. Dent. PD MAR PY 1999 VL 81 IS 3 BP 356 EP 364 DI 10.1016/S0022-3913(99)70280-5 PG 9 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 181HC UT WOS:000079434600016 PM 10050125 ER PT J AU Thompson, MM AF Thompson, MM TI Using a GIS to integrate seasonal raptor distributions into a bird avoidance model for aircraft SO JOURNAL OF RAPTOR RESEARCH LA English DT Article ID FLIGHT BEHAVIOR; MIGRATION; HAWKS; RADAR C1 HQ AFCESA, DMPS, Tyndall AFB, FL 32403 USA. RP Thompson, MM (reprint author), HQ AFCESA, DMPS, 139 Barnes Dr, Tyndall AFB, FL 32403 USA. NR 26 TC 1 Z9 1 U1 1 U2 3 PU RAPTOR RESEARCH FOUNDATION INC PI HASTINGS PA 14377 117TH STREET SOUTH, HASTINGS, MN 55033 USA SN 0892-1016 J9 J RAPTOR RES JI J. Raptor Res. PD MAR PY 1999 VL 33 IS 1 BP 53 EP 58 PG 6 WC Ornithology SC Zoology GA 190RQ UT WOS:000079978800006 ER PT J AU Holley, JE Butler, JW Mahoney, JM AF Holley, JE Butler, JW Mahoney, JM TI Carbon monoxide poisoning in racing car drivers SO JOURNAL OF SPORTS MEDICINE AND PHYSICAL FITNESS LA English DT Article DE carbon monoxide AB Background. To determine if carbon monoxide (CO) exposure during competition racing is significant enough to cause post-racing symptoms among professional racing drivers. Methods. Closed vehicle professional racing drivers were questioned after competition regarding symptoms consistent with heat exposure, dehydration, and carbon monoxide poisoning. All drivers, regardless of symptoms, underwent expired CO monitoring using a breath analyzer both before and after competition events, CO measurements were performed prior to any post-race interviews. Driver smoking history, laps at low speed (under caution), cockpit fire or damage to the exhaust system were also noted. An association between driver symptoms, track and vehicle condition, and increases in expired CO levels during racing was sought. Results. Twenty-eight drivers completed the study. Each driver was tested both before and after each competition event, and some drivers were tested at different tracks, All of the tested drivers experienced an increase in carboxyhemoglobin concentrations during the competition event, Drivers who smoked had higher baseline levels than non-smokers, but were no more likely to have symptoms, The driver with the highest post-race CO level was exposed to a fire which completely destroyed the vehicle, but he complained of no symptoms after the race. Most drivers complained of post-race symptoms or appeared symptomatic, but no correlation could be shown between post-race CO levels and symptoms, Conclusions. There is a mild increase in driver CO levels during professional road racing competition, however, no correlation with CO level and driver symptomatology can be demonstrated. Carbon monoxide does not appear to be a significant cause of post-race driver symptoms such as fatigue, nausea, headache, and weakness. C1 Baptist Mem Hosp, Dept Emergency Med, Memphis, TN 38146 USA. Rapid Response Team, SCCA Pro Racing, Englewood, CO USA. Genex Serv Inc, Waukesha, WI USA. USAF, Sch Aerosp Med, Brooks AFB, TX 78235 USA. Colombia Hosp, Emergency Dept, Milwaukee, WI USA. RP Holley, JE (reprint author), 8474 Windolyn Circle N, Memphis, TN 38133 USA. NR 12 TC 5 Z9 7 U1 0 U2 2 PU EDIZIONI MINERVA MEDICA PI TURIN PA CORSO BRAMANTE 83-85 INT JOURNALS DEPT., 10126 TURIN, ITALY SN 0022-4707 J9 J SPORT MED PHYS FIT JI J. Sports Med. Phys. Fit. PD MAR PY 1999 VL 39 IS 1 BP 20 EP 23 PG 4 WC Sport Sciences SC Sport Sciences GA 188YG UT WOS:000079876500004 PM 10230164 ER PT J AU Parthasarathy, TA Kerans, RJ Pagano, NJ AF Parthasarathy, TA Kerans, RJ Pagano, NJ TI Effective fiber properties to incorporate coating thermoelastic effects in fiber/matrix composite models SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID BRITTLE-MATRIX COMPOSITES; INTERFACIAL ROUGHNESS; CERAMIC COMPOSITES; REINFORCED CERAMICS; STRESSES; BEHAVIOR AB A method to incorporate the thermoelastic effects of fiber coatings into models of fiber/matrix composites was determined. The coated fiber was replaced by an "effective" transversely isotropic fiber so that the properties of this effective fiber could be used in composite models. This approach was used to determine the magnitude of errors resulting from neglect of the coatings in modeling fiber/ matrix debonding and sliding and in reduction of data from real composites. The effects of carbon and BN coatings in the Nicalon/SiC system were found to be significant. It was found that significant errors could be expected from fitting models to experimental data if the compliance and coefficient of thermal expansion of the coatings were ignored, even when the coatings were thin. Wide use of the approach required revision of composite models to allow inclusion of a transversely isotropic fiber. Such a revision was derived for a popular model of matrix cracking stress, and significant effects again were found to result from neglect of coatings. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RP Parthasarathy, TA (reprint author), UES Inc, Dayton, OH USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 19 TC 4 Z9 4 U1 1 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAR PY 1999 VL 82 IS 3 BP 579 EP 584 PG 6 WC Materials Science, Ceramics SC Materials Science GA 180FE UT WOS:000079374400012 ER PT J AU Ravichandran, KS An, K Dutton, RE Semiatin, SL AF Ravichandran, KS An, K Dutton, RE Semiatin, SL TI Thermal conductivity of plasma-sprayed monolithic and multilayer coatings of alumina and yttria-stabilized zirconia SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT 99th United Thermal Spray Conference CY SEP 15-18, 1997 CL INDIANAPOLIS, INDIANA ID BARRIER COATINGS; DIFFUSIVITY; ZRO2 AB The temperature dependence of the thermal conductivity of plasma-spray-deposited monolithic coatings, as well as multilayer coatings that consisted of Al2O3 and ZrO2 that was stabilized by 8% Y2O3 (YSZ), was investigated. The coatings exhibited a large reduction in thermal conductivity at all temperatures, when compared to the bulk monolithic Al2O3 and YSZ. This reduction was due to porosity as well as thermal resistance that was caused by interfaces in the coatings. The largest decrease in the thermal conductivity of the coatings, relative to monolithic fully dense materials, was due to splat interfaces within each layer, as well as the coating/substrate interface. On the other hand, the multilayer coatings showed little variation in the thermal conductivity, relative to the number of layers, which suggests that the influence of interlayer interfaces on heat transfer is relatively small. A one-dimensional analysis of steady-state heat transfer has been presented to illustrate the significance of porosity, splat interfaces, and interlayer interfaces, with respect to the overall thermal conductivity of multilayer coatings. C1 Univ Utah, Dept Met Engn, Salt Lake City, UT 84112 USA. USAF, Res Lab, MLLM, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Ravichandran, KS (reprint author), Univ Utah, Dept Met Engn, Salt Lake City, UT 84112 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 29 TC 65 Z9 66 U1 1 U2 11 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAR PY 1999 VL 82 IS 3 BP 673 EP 682 PG 10 WC Materials Science, Ceramics SC Materials Science GA 180FE UT WOS:000079374400024 ER PT J AU Davis, A Vaccaro, K Dauplaise, HM Waters, WD Lorenzo, JP AF Davis, A Vaccaro, K Dauplaise, HM Waters, WD Lorenzo, JP TI Optimization of chemical bath-deposited cadmium sulfide on InP using a novel sulfur pretreatment SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID PASSIVATED INP; INDIUM-PHOSPHIDE; SILICON-NITRIDE; THIN-FILMS; SURFACE; LAYERS; SPECTROSCOPY; GROWTH AB A thiourea/ammonia pretreatment followed by chemical bath deposition of cadmium sulfide was used to passivate the surface of indium phosphide (100). The pretreatment was shown by X-ray photoelectron spectroscopy to effectively remove native oxides from the InP surface and form an indium sulfide layer. The subsequent chemical bath deposition of CdS on a sulfur-passivated surface forms a stable layer that protects the substrate from oxidation during chemical vapor deposition of SiO2. The passivation process was optimized for electrical response by varying the reactant concentrations of the chemical bath. Reflection high-energy electron-diffraction (RHEED) analysis showed that the pretreatment results in a (1 x 1) surface, which reconstructs to (2 x 1) after heating in vacuo to 200 degrees C. RHEED and atomic force microscopy showed an increase in CdS surface roughness with increasing thickness corresponding to the formation of oriented surface asperities. CdS-passivated metal-insulator-semiconductor diodes exhibited a density of interface states (D-it) of 10(11) eV(-1) cm(-2) when calculated by the high-low method, more than one order of magnitude lower than the D-it of untreated metal-insulator-semiconductor samples. A CdS layer thickness of similar to 10 Angstrom was determined to yield optimal capacitance-voltage response for all CdS deposition conditions investigated. (C) 1999 The Electrochemical Society. S0013-4651(98)04-023-3. All rights reserved. C1 USAF, Res Lab, Sensor Directorate, Optoelect Technol Branch, Hanscom AFB, MA 01731 USA. Solid State Sci Corp, Hollis, NH 03049 USA. RP Davis, A (reprint author), USAF, Res Lab, Sensor Directorate, Optoelect Technol Branch, Hanscom AFB, MA 01731 USA. NR 21 TC 11 Z9 11 U1 0 U2 1 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAR PY 1999 VL 146 IS 3 BP 1046 EP 1053 DI 10.1149/1.1391719 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 178XG UT WOS:000079294000034 ER PT J AU Matson, CL Liu, HL AF Matson, CL Liu, HL TI Analysis of the forward problem with diffuse photon density waves in turbid media by use of a diffraction tomography model SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID OPTICAL-COHERENCE TOMOGRAPHY; SCATTERING MEDIA; IMAGE-RECONSTRUCTION; SAMPLING THEOREMS; TISSUE; INHOMOGENEITIES; SIGNAL AB We extend our previously developed diffraction tomography model of diffuse photon density wave propagation in turbid media to analyze the forward problem associated with detecting and resolving both absorptive and scattering inhomogeneities. Our results assume that detection occurs in a plane but no restrictions are placed on the illumination source geometry. We then specialize these results to plane-wave illumination and derive the turbid media version of the Fourier diffraction theorem. We also develop a shot-noise-limited Fourier-domain signal-to-noise-ratio (SNR) expression to determine how background, system, and inhomogeneity parameters affect one's ability to detect and resolve inhomogeneities. We show that, in general, scattering inhomogeneities are more easily resolved than absorbing inhomogeneities. We also show that lower temporal modulation frequencies enhance one's ability to detect and resolve inhomogeneities. These theoretical results are compared with previously published image-domain SNR results, and qualitative agreement is demonstrated. (C) 1999 Optical Society of America [S0740-3232(99)01203-X]. C1 USAF, Res Lab, Adv opt & Imaging Div, Kirtland AFB, NM 87117 USA. Univ Texas, Dept Biomed Engn, Arlington, TX 76019 USA. RP Matson, CL (reprint author), USAF, Res Lab, Adv opt & Imaging Div, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 37 TC 19 Z9 19 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD MAR PY 1999 VL 16 IS 3 BP 455 EP 466 DI 10.1364/JOSAA.16.000455 PG 12 WC Optics SC Optics GA 170AQ UT WOS:000078783300004 ER PT J AU Ellerbroek, BL AF Ellerbroek, BL TI Power series evaluation of covariances for turbulence-induced phase distortions including outer scale and servo lag effects SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID ADAPTIVE-OPTICS SYSTEMS; ASTRONOMICAL TELESCOPES; PERFORMANCE; FIELD AB Power series formulas are developed to efficiently compute the covariance of the integrated turbulence-induced phase distortions along a pair of ray paths through the atmosphere from two points in a telescope aperture to a pair of sources at finite or infinite range. These covariances may be used to evaluate and optimize the predicted performance of adaptive optical (AO) systems. The power series formulas apply when one or both of the phase distortions is temporally filtered by the closed-loop impulse response function of the AO control loop, thereby allowing the effects of a finite servo bandwidth to be included in AO system performance modeling without the introduction of additional numerical integrations. Results are presented for the Kolomogorov turbulence spectrum with an infinite outer scale, as well as for the case of a finite outer scale with the von Karman turbulence spectrum. Amplitude scintillation effects are neglected. The Taylor, or frozen flow, hypothesis is used to model the temporal behavior of the turbulence, by using a fixed windspeed profile w(z) and a random wind direction profile theta(w)(z) for which the mean values of the quantities cos[k theta(w)(z)] and sin[k theta(w)(z)] can be computed. The resulting formulas for the covariances are weighted integrals of the refractive-index structure constant C-n(2)(z), where the weighting functions are power series in from one to three indices depending on the choices made regarding the atmospheric turbulence spectrum and the direction of the wind. The integral with respect to z may also be evaluated analytically, provided that (i) the C-n(2)(z) profile is a sum of terms of the form z(P) exp(-cz) and (ii) the phase distortion profiles are not temporally filtered. (C) 1999 Optical Society of America [S0740-3232(99)03603 -0]. C1 USAF, Res Lab, Starfire Opt Range, Kirtland AFB, NM 87117 USA. RP Ellerbroek, BL (reprint author), USAF, Res Lab, Starfire Opt Range, Kirtland AFB, NM 87117 USA. NR 15 TC 3 Z9 3 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD MAR PY 1999 VL 16 IS 3 BP 533 EP 548 DI 10.1364/JOSAA.16.000533 PG 16 WC Optics SC Optics GA 170AQ UT WOS:000078783300012 ER PT J AU Koch, K Moore, GT AF Koch, K Moore, GT TI Singly resonant cavity-enhanced frequency tripling SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID INTRACAVITY 2ND-HARMONIC GENERATION; OPTICAL-PARAMETRIC OSCILLATION; HARMONIC-GENERATION; RING CAVITY; CONVERSION; EFFICIENCY; NM AB We use a plane-wave analysis to examine a singly resonant, cavity-enhanced, frequency doubler containing an intracavity sum-frequency interaction that frequency sums the resonant fundamental with the second harmonic to produce the third harmonic of the resonant field. We derive expressions for the steady-state performance of the device. We determine the input coupler intensity reflectivity and the ratio of nonlinear drives between the second-harmonic generation (SHG) and sum-frequency generation (SFG) stages for optimum third-harmonic conversion efficiency. We also examine the optimum SHG interaction length under conditions of limited total interaction length. We find that numerical simulations modeling three spatial dimensions can be closely approximated by appropriately scaled plane-wave results. As an example, we consider frequency tripling of a 350-mW, 1319-nm, cw laser in two consecutive nonlinear gratings in periodically poled Lithium niobate and iind third-harmonic power-conversion efficiency of 85.3% when first-order quasi-phase-matching (QPM) is used for the SFG process and 51.0% when third-order SFG QPM is used. We also consider frequency tripling of a 20-W, 1064-nm, continuous-wave mode-locked laser in two lithium triborate crystals and find a time-averaged third-harmonic power-conversion efficiency of 56.0% from modeling three spatial dimensions. (C) 1999 Optical Society of America [S0740-3224(99)01403-4]. OCIS codes: 190.0190, 190.7220, 190.4360. C1 USAF, Res Lab, DELO, Solid State Laser & Nonlinear Opt Branch, Kirtland AFB, NM 87117 USA. Univ New Mexico, Ctr Adv Studies, Albuquerque, NM 87131 USA. RP Koch, K (reprint author), Corning Inc, SP-AR-02-4, Corning, NY 14831 USA. NR 26 TC 13 Z9 13 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAR PY 1999 VL 16 IS 3 BP 448 EP 459 DI 10.1364/JOSAB.16.000448 PG 12 WC Optics SC Optics GA 174ET UT WOS:000079021700014 ER PT J AU Teichman, JMH Vassar, GJ Yates, JT Angle, BN Johnson, AJ Dirks, MS Thompson, IM AF Teichman, JMH Vassar, GJ Yates, JT Angle, BN Johnson, AJ Dirks, MS Thompson, IM TI Color vision deficits and laser eyewear protection for soft tissue laser applications SO JOURNAL OF UROLOGY LA English DT Article DE lasers; color perception; eye protective devices; spectrophotometry ID MUNSELL 100-HUE TEST; PERFORMANCE; WAVELENGTH AB Purpose: Laser safety considerations require urologists to wear laser eye protection. Laser eye protection devices block transmittance of specific light wavelengths and may distort color perception. We tested whether urologists risk color confusion when wearing laser eye protection devices for laser soft tissue applications. Materials and Methods: Subjects were tested with the Farnsworth-Munsell 100-Hue Test without (controls) and with laser eye protection devices for carbon dioxide, potassium titanyl phosphate (KTP), neodymium (Nd):YAG and holmium:YAG lasers. Color deficits were characterized by error scores, polar graphs, confusion angles, confusion index, scatter index and color axes. Laser eye protection device spectral transmittance was tested with spectrophotometry. Results: Mean total error scores plus or minus standard deviation were 13 +/- 5 for controls, and 44 +/- 31 for carbon dioxide, 273 +/- 26 for KTP, 22 +/- 6 for Nd:YAG and 14 +/- 8 for holmium:YAG devices (p <0.001). The KTP laser eye protection polar graphs, and confusion and scatter indexes revealed moderate blue-yellow and red-green color confusion. Color axes indicated no significant deficits for controls, or carbon dioxide, Nd:YAG or holmium:YAG laser eye protection in any subject compared to blue-yellow color vision deficits in 8 of 8 tested with KTP laser eye protection (p <0.001). Spectrophotometry demonstrated that light was blocked with laser eye protection devices for carbon dioxide less than 380, holmium:YAG greater than 850, Nd:YAG less than 350 and greater than 950, and KTP less than 550 and greater than 750 nm. Conclusions: The laser eye protection device for KTP causes significant blue-yellow and red-green color confusion. Laser eye protection devices for carbon dioxide, holmium:YAG and Nd:YAG cause no significant color confusion compared to controls. The differences are explained by laser eye protection spectrophotometry characteristics and visual physiology. C1 Brooke Army Med Ctr, Dept Ophthalmol, Ft Sam Houston, TX 78234 USA. Brooke Army Med Ctr, Div Urol, Ft Sam Houston, TX 78234 USA. Univ Texas, Hlth Sci Ctr, Div Urol, San Antonio, TX 78284 USA. Aeromed Consultat Serv, Ophthalmol Branch, Brooks AFB, TX USA. Armstrong Lab, Visual Electrodiagnost Lab, Brooks AFB, TX 78235 USA. RP Teichman, JMH (reprint author), Univ Texas, Hlth Sci Ctr, Div Urol, San Antonio, TX 78284 USA. NR 19 TC 6 Z9 6 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0022-5347 J9 J UROLOGY JI J. Urol. PD MAR PY 1999 VL 161 IS 3 BP 874 EP 880 DI 10.1016/S0022-5347(01)61795-6 PG 7 WC Urology & Nephrology SC Urology & Nephrology GA 164YZ UT WOS:000078492300036 PM 10022704 ER PT J AU Xie, QH Van Nostrand, JE AF Xie, QH Van Nostrand, JE TI Line-of-sight mass spectrometric study of As/Sb exchange on Sb-terminated and Ga-terminated GaSb (001) during molecular beam epitaxy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID INAS/GASB SUPERLATTICES; INTERFACES; INAS; MICROSCOPY; ASYMMETRY; QUALITY; GROWTH; ALLOYS AB Rates and total amounts of the arsenic for antimony exchange reaction on the GaSb (001) surface are measured via line-of-sight mass spectrometry during molecular beam epitaxial growth. On the Sb-terminated GaSb (001) surface, an As for Sb exchange is observed to occur at all levels of incident As-2 flux studied. By contrast, on the surface with one monolayer of Ga, there exists a critical As-2 flux below which the As for Sb exchange is suppressed, and a two-dimensional (2D) surface morphology is maintained. Above the critical As-2 flux, the As for Sb exchange is observed to be linear with increasing As-2 flux. Substrate temperatures above 470 degrees C and As-2 fluxes greater than 1 x 10(-6) Ton beam flux pressure lead to a drastic increase in As/Sb exchange accompanied by the occurrence of 3D surface morphology. As/Sb exchange at the interfaces of InAs/GaSb type-II superlattices leads to a reduced average lattice constant of the superlattices and degrades interface quality, as determined by x-ray diffraction. (C) 1999 American Vacuum Society. [S0734-2101(99)03102-4]. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Xie, QH (reprint author), NE Consortium Engn Educ, 1101 Massachusetts Ave, St Cloud, FL 34769 USA. NR 25 TC 9 Z9 9 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAR-APR PY 1999 VL 17 IS 2 BP 342 EP 346 DI 10.1116/1.581593 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 177GX UT WOS:000079203200004 ER PT J AU Leyendecker, JR AF Leyendecker, JR TI Optimal digital subtraction angiography of dorsalis pedis artery: Effect of foot positioning on angiographic demonstration - Response SO JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY LA English DT Letter C1 Wilford Hall USAF Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. RP Leyendecker, JR (reprint author), Wilford Hall USAF Med Ctr, Dept Radiol, 2200 Berquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1051-0443 J9 J VASC INTERV RADIOL JI J. Vasc. Interv. Radiol. PD MAR PY 1999 VL 10 IS 3 BP 376 EP 377 DI 10.1016/S1051-0443(99)70049-7 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging; Peripheral Vascular Disease SC Radiology, Nuclear Medicine & Medical Imaging; Cardiovascular System & Cardiology GA 177HE UT WOS:000079203900024 ER PT J AU Tsai, CT Liou, LL AF Tsai, CT Liou, LL TI Dislocation dynamics in heterojunction bipolar transistor under current induced thermal stress SO MICROELECTRONICS RELIABILITY LA English DT Article AB Dislocation generation and multiplication in heterojunction bipolar transistors (HBTs) under electrical bias was studied using a finite element model. This model was developed to solve a physical viscoplastic solid mechanics problem using a time-dependent constitutive equation relating the dislocation dynamics to plastic deformation. The dislocations in HBTs are generated by the excessive stresses including thermal stress generated by the temperature change in the device during operation. It was found that the dislocation generation rate at the;early stage and the stationary dislocation densities depend strongly on the current density. (C) 1999 Elsevier Science Ltd. Ail rights reserved. C1 Florida Atlantic Univ, Dept Mech Engn, Boca Raton, FL 33431 USA. USAF, Res Lab, Sensor Directorate, Wright Patterson AFB, OH 45433 USA. RP Tsai, CT (reprint author), Florida Atlantic Univ, Dept Mech Engn, Boca Raton, FL 33431 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0026-2714 J9 MICROELECTRON RELIAB JI Microelectron. Reliab. PD MAR PY 1999 VL 39 IS 3 BP 383 EP 389 DI 10.1016/S0026-2714(98)00246-7 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 206QH UT WOS:000080890200008 ER PT J AU Hartman, ME AF Hartman, ME TI The US Army from the Normandy beaches to the bulge to the surrender of Germany, June 7, 1944 May 7, 1945 SO MILITARY LAW REVIEW LA English DT Book Review C1 USAF, Washington, DC 20330 USA. RP Hartman, ME (reprint author), USAF, Washington, DC 20330 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU JUDGE ADVOCATE GENERALS SCHOOL PI CHARLOTTESVILLE PA US ARMY, CHARLOTTESVILLE, VA 22903-1781 USA SN 0026-4040 J9 MIL LAW REV JI Milit. Law Rev. PD MAR PY 1999 VL 159 BP 210 EP 217 PG 8 WC Law SC Government & Law GA 187QU UT WOS:000079798900006 ER PT J AU Lipton, AE Modica, GD AF Lipton, AE Modica, GD TI Assimilation of visible-band satellite data for mesoscale forecasting in cloudy conditions SO MONTHLY WEATHER REVIEW LA English DT Article ID STRATUS CLOUD; MODEL; SYSTEM; SCHEME; PREDICTION; RETRIEVAL; FLOW AB Assimilation of satellite data can enhance the ability of a mesoscale modeling system to produce accurate short-term forecasts of clouds and precipitation, but only if there is a mechanism for the satellite-derived information to propagate coherently from the analysis into the forecast period. In situations where stratiform cloud cover inhibits surface heating, assimilation of visible image data can be beneficial for analyses, but those data present particular challenges for application to numerical forecasts. To address the forecast problem, a method to adjust the humidity field and the radiative parameterization of a model was developed such that satellite retrievals of cloud properties have an Impact that extends well into the forecast. The adjustment directs the model's cloud diagnosis and radiation algorithms to produce results that agree with satellite retrievals valid at the forecast initiation time. Experiments showed a high level of fidelity between a short-term forecast made with this method and coincident analyses produced with satellite data. In comparison with a forecast made using a standard model formulation, the adjusted model produced 1) surface insolation fields that were far more realistic, 2) more accurate shelter-height temperatures, and 3) mesoscale circulation features that were more consistent with observed diurnal convective cloud development. C1 USAF, Res Lab, Geophys Directorate, Opt Effects Div, Hanscom AFB, MA USA. RP Lipton, AE (reprint author), Atmospher & Environm Res Inc, 840 Mem Dr, Cambridge, MA 02139 USA. NR 18 TC 10 Z9 12 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0027-0644 J9 MON WEATHER REV JI Mon. Weather Rev. PD MAR PY 1999 VL 127 IS 3 BP 265 EP 278 DI 10.1175/1520-0493(1999)127<0265:AOVBSD>2.0.CO;2 PG 14 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 171NH UT WOS:000078869700001 ER PT J AU Ahmed, F Awwal, AAS Power, GJ AF Ahmed, F Awwal, AAS Power, GJ TI Synthetic correlation-based modified signed-digit trinary logic processing SO OPTICAL ENGINEERING LA English DT Article DE modified signed-digit; synthetic matched filter; correlation; trinary logic ID SYMBOLIC SUBSTITUTION; IMPLEMENTATION; ADDER AB An optical implementation using a correlation technique for modified signed-digit (MSD) trinary logic processing is presented. In particular, a synthetic matched filter (SMF) correlator model is used to demonstrate the realization of the carry-propagation-free trinary MSD addition. It is shown that proper encoding of the MSD numerals are of utmost importance for the correlator model to work. The developed method is expected to have far-reaching application in the optical higher radix numeric and logic processing, (C) 1999 Society of Photo-Optical instrumentation Engineers. [S0091-3286(99)01003-X]. C1 Penn State Univ, Behrend Coll, Sch Engn & Engn Technol, Erie, PA 16563 USA. Wright State Univ, Dept Comp Sci & Engn, Dayton, OH 45435 USA. USAF, Res Lab, AFRL, SNAT Target Recognit Branch, Wright Patterson AFB, OH 45433 USA. RP Ahmed, F (reprint author), Penn State Univ, Behrend Coll, Sch Engn & Engn Technol, Erie, PA 16563 USA. EM fxa9@psu.edu NR 19 TC 2 Z9 2 U1 0 U2 0 PU SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 0091-3286 EI 1560-2303 J9 OPT ENG JI Opt. Eng. PD MAR PY 1999 VL 38 IS 3 BP 449 EP 455 DI 10.1117/1.602121 PG 7 WC Optics SC Optics GA 176MY UT WOS:000079156400008 ER PT J AU Cairns, ML Knable, AL AF Cairns, ML Knable, AL TI Multiple eruptive milia in a 15-year-old boy SO PEDIATRIC DERMATOLOGY LA English DT Article ID EN-PLAQUE; TRICHOEPITHELIOMAS; HYPOTRICHOSIS; DOMINANT AB We present a 15-year-old boy with periorbital idiopathic multiple eruptive milia. He represents the youngest case to date of this unusual dermatosis. C1 Wright State Univ, Dermatol Sect, Dayton, OH 45435 USA. RP Knable, AL (reprint author), Dept Dermatol, Wright Patterson AFB, Wright Patterson AFB, OH 45433 USA. NR 24 TC 10 Z9 10 U1 0 U2 0 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0736-8046 J9 PEDIATR DERMATOL JI Pediatr. Dermatol. PD MAR-APR PY 1999 VL 16 IS 2 BP 108 EP 110 DI 10.1046/j.1525-1470.1999.99010.x PG 3 WC Dermatology; Pediatrics SC Dermatology; Pediatrics GA 188JG UT WOS:000079842600005 PM 10337672 ER PT J AU Njus, DM Brockway, JH AF Njus, DM Brockway, JH TI Perceptions of competence and locus of control for positive and negative outcomes: predicting depression and adjustment to college SO PERSONALITY AND INDIVIDUAL DIFFERENCES LA English DT Article ID PERCEIVED SELF-EFFICACY; LIFE EVENTS; PERFORMANCE; BELIEFS; STRESS; HEALTH; ATTRIBUTIONS; ACHIEVEMENT; MODERATORS; ILLNESS AB The relationship locus of control (LOC) and perceived competence have with depression and academic and social adjustment was examined in two studies. In study 1, internal LOC for positive but not negative outcomes was associated with lower levels of depression. Perceived competence, the belief that you can affect outcomes in your life, accounted for additional variance in depression scores beyond that of LOG. In study 2, LOC and competence were examined for their relationship to academic and social adjustment. As in study 1, internal LOC over; positive outcomes was associated with better adjustment than internal LOC over negative outcomes. Perceptions of competence explained variance in adjustment scores beyond that explained by LOG. Domain-specific measures of control and competence also contributed to an explanation of both social and academic adjustment. The results contradict previous research indicating that LOC over positive and negative outcomes are both beneficial. (C) 1999 Elsevier Science Ltd, All rights reserved. C1 Luther Coll, Dept Psychol, Decorah, IA 52101 USA. USAF Acad, Colorado Springs, CO 80840 USA. RP Njus, DM (reprint author), Luther Coll, Dept Psychol, Decorah, IA 52101 USA. NR 29 TC 7 Z9 7 U1 2 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0191-8869 J9 PERS INDIV DIFFER JI Pers. Individ. Differ. PD MAR PY 1999 VL 26 IS 3 BP 531 EP 548 DI 10.1016/S0191-8869(98)00169-X PG 18 WC Psychology, Social SC Psychology GA 164KH UT WOS:000078462800009 ER PT J AU Patterson, BM Takekoshi, T Knize, RJ AF Patterson, BM Takekoshi, T Knize, RJ TI Measurement of the photoionization cross section of the 6P(3/2) state of cesium SO PHYSICAL REVIEW A LA English DT Article AB We report the measurement of the absolute photoionization cross section for the 6P(3/2) State of cesium. Cross sections were determined by measuring title photoionization rate of cesium atoms confined in a magneto-optical trap. The photoionization rate was measured by monitoring the decay of trap fluorescence during exposure to ionizing laser radiation. The measurements were made in the wavelength range 457.9 to 501.7 nm using several lines from an At-ion laser. Our results are compared to other experimental measurements as well as to existing theories. [S1050-2947(99)06603-2]. C1 USAF Acad, Dept Phys, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. RP Patterson, BM (reprint author), USAF Acad, Dept Phys, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. NR 7 TC 25 Z9 27 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAR PY 1999 VL 59 IS 3 BP 2508 EP 2510 DI 10.1103/PhysRevA.59.2508 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 177WC UT WOS:000079233200099 ER PT J AU Browning, SM AF Browning, SM TI Constipation, diarrhea, and irritable bowel syndrome SO PRIMARY CARE LA English DT Article ID SLOW TRANSIT CONSTIPATION; BALLOON EXPULSION TEST; UNITED-STATES; OUTLET OBSTRUCTION; GASTROINTESTINAL DISORDERS; IDIOPATHIC CONSTIPATION; PUBORECTALIS SYNDROME; COLONIC MOTILITY; PEPTIC-ULCER; DOUBLE-BLIND AB Constipation, diarrhea, and irritable bowel, syndrome are commonly encountered in the primary care practice. Most episodes of constipation and diarrhea are benign and self-limited. Patients with chronic constipation should undergo a screening evaluation to exclude organic disease, after which most can be managed successfully with dietary modification and fiber supplementation. The cause of chronic diarrhea usually can be discerned clinically, with irritable bowel syndrome, inflammatory bowel disease, and lactose intolerance being diagnosed most frequently. Irritable bowel syndrome is a functional gastrointestinal disorder characterized by abdominal pain and disordered defecation, which is successfully managed with a strong physician-patient relationship and periodic pharmacologic intervention. C1 Wilford Hall USAF Med Ctr, Dept Surg, San Antonio, TX 78236 USA. RP Wilford Hall USAF Med Ctr, Dept Gen Surg, Lackland AFB, TX 78236 USA. NR 95 TC 9 Z9 9 U1 0 U2 2 PU W B SAUNDERS CO-ELSEVIER INC PI PHILADELPHIA PA 1600 JOHN F KENNEDY BOULEVARD, STE 1800, PHILADELPHIA, PA 19103-2899 USA SN 0095-4543 EI 1558-299X J9 PRIMARY CARE JI Primary Care PD MAR PY 1999 VL 26 IS 1 BP 113 EP + DI 10.1016/S0095-4543(05)70105-6 PG 28 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 168XL UT WOS:000078718400009 PM 9922298 ER PT J AU Henderson, JH Strollo, PJ AF Henderson, JH Strollo, PJ TI Medical management of obstructive sleep apnea SO PROGRESS IN CARDIOVASCULAR DISEASES LA English DT Review ID POSITIVE AIRWAY PRESSURE; APPETITE-SUPPRESSANT DRUGS; RESPIRATORY MOTOR-ACTIVITY; WEIGHT-REDUCTION SURGERY; OBESE PATIENTS; PULMONARY-HYPERTENSION; DAYTIME SLEEPINESS; ORAL APPLIANCES; CPAP TITRATION; NASAL CPAP C1 Uniformed Serv Univ Hlth Sci, Wilford Hall USAF Med Ctr, Lackland AFB, TX USA. Univ Pittsburgh, Sch Med, Div Pulm Allergy & Crit Care Med, Pittsburgh, PA USA. RP Strollo, PJ (reprint author), Montefiore Univ Hosp, 3459 5th Ave,Suite S-643, Pittsburgh, PA 15213 USA. NR 107 TC 7 Z9 8 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0033-0620 J9 PROG CARDIOVASC DIS JI Prog. Cardiovasc. Dis. PD MAR-APR PY 1999 VL 41 IS 5 BP 377 EP 386 DI 10.1053/pcad.1999.0410377 PG 10 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 212UH UT WOS:000081235500006 PM 10406331 ER PT J AU Murchison, DF Charlton, DG Moore, WS AF Murchison, DF Charlton, DG Moore, WS TI Comparative radiopacity of flowable resin composites SO QUINTESSENCE INTERNATIONAL LA English DT Article DE dental radiography; radiodensity; radiopacity; resin composite ID IONOMER DENTAL MATERIALS; RESTORATIVE MATERIALS; POSTERIOR COMPOSITES; CEMENTS; CARIES AB Objective: This in vitro investigation aimed to determine the radiopacity of eight recently introduced "flowable" restorative resin composites and to compare their radiodensities to those of enamel, dentin, and a widely used composite marketed for universal application in anterior and posterior teeth. Method and materials: A total of 45 composite specimens were fabricated in cylindrical molds and exposed to a curing light for 120 seconds. Two methods were used to determine radiopacity: a transmission densitometer and a computer-assisted densitometric image analysis station. Results: Of the eight flowable resin composites tested, only three exhibited a radiopacity equal to or greater than that of enamel, a widely followed guideline for clinicians' diagnostic ability The radiopacity of the remaining five materials was not statistically significantly greater than that of dentin. Conclusion: The level of radiopacity of the tested flowable composites was variable; those with low radiodensity should be avoided in Class II restorations, where a clear determination of recurrent caries by the examining clinician could be compromised. C1 Dept Gen Dent, Lackland AFB, TX 78236 USA. USAF, Dent Invest Serv, Brooks AFB, TX USA. RP Murchison, DF (reprint author), 59 MDW-MDRG,1615 Truemper St, Lackland AFB, TX 78236 USA. NR 22 TC 28 Z9 30 U1 0 U2 1 PU QUINTESSENCE PUBL CO INC PI CAROL STREAM PA 551 NORTH KIMBERLY DR, CAROL STREAM, IL 60188-1881 USA SN 0033-6572 J9 QUINTESSENCE INT JI Quintessence Int. PD MAR PY 1999 VL 30 IS 3 BP 179 EP 184 PG 6 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 177JD UT WOS:000079206100006 PM 10356571 ER PT J AU Buchholz, TA McCabe, K Cobb, J Haroff, H Prestidge, BR Ehler, WJ AF Buchholz, TA McCabe, K Cobb, J Haroff, H Prestidge, BR Ehler, WJ TI TP53 overexpression in radiation-induced osteosarcoma of the rabbit mandible SO RADIATION RESEARCH LA English DT Article ID P53; SARCOMA AB The objective of this study was to investigate the incidence of overexpression of TP53 (formerly known as p53) in osteosarcomas occurring after treatment of rabbit mandibles with high-dose external-beam radiation. As part of a protocol investigating hyperbaric oxygen treatment for osteoradionecrosis, 102 female New Zealand-White rabbits underwent mandibular radiation treatments with a total dose of 64 Gy in 20 treatment fractions, Twelve animals died during irradiation, leaving 90 animals at risk for tumor development. These animal were divided into one control group and 12 other groups each treated with different schedules of postirradiation hyperbaric oxygen. All animals were sacrificed after the hyperbaric oxygen treatment, approximately 8 months after completion of irradiation. Seventeen of the 90 animals that survived after irradiation developed high-grade osteosarcomas, for a 19% incidence of malignancy. Tumor sizes ranged from 1-4 cm, Immunohistochemistry staining of the 17 tumors detected a 59% overall incidence of TP53 overexpression. There was no correlation between the intensity of hyperbaric oxygen treatment and development of osteosarcoma, The high incidence and short interval of development of osteosarcoma suggest that the study animals may have had a genetic predisposition to radiation-induced osteosarcoma, Additionally, our data pro,ide further evidence that TP53 mutations may play an important role in radiation-induced osteosarcoma. (C) 1999 by Radiation Research Society. C1 Univ Texas, MD Anderson Cancer Ctr, Dept Radiat Oncol, Houston, TX 77030 USA. Mesa Lutheran Hosp, Dept Pathol, Phoenix, AZ USA. Wilford Hall Med Ctr, Dept Anim Med, Lackland AFB, TX USA. Wilford Hall USAF Med Ctr, Dept Radiat Oncol, Lackland AFB, TX 78236 USA. RP Buchholz, TA (reprint author), Univ Texas, MD Anderson Cancer Ctr, Dept Radiat Oncol, 1515 Holcombe Blvd, Houston, TX 77030 USA. NR 20 TC 4 Z9 4 U1 0 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAR PY 1999 VL 151 IS 3 BP 278 EP 282 DI 10.2307/3579939 PG 5 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 172NX UT WOS:000078931600006 PM 10073665 ER PT J AU Dubois, DF AF Dubois, DF TI Statistical evaluation of agreement - Dr Dubois responds SO RADIOLOGY LA English DT Letter C1 Wilford Hall USAF Med Ctr, Dept Radiat Oncol, Lackland AFB, TX 78236 USA. RP Dubois, DF (reprint author), Wilford Hall USAF Med Ctr, Dept Radiat Oncol, 2200 Berguist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 USA SN 0033-8419 J9 RADIOLOGY JI Radiology PD MAR PY 1999 VL 210 IS 3 BP 882 EP 882 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 170FW UT WOS:000078796500055 ER PT J AU Tabib-Azar, M Su, DP Pohar, A LeClair, SR Ponchak, G AF Tabib-Azar, M Su, DP Pohar, A LeClair, SR Ponchak, G TI 0.4 mu m spatial resolution with 1 GHz (lambda = 30 cm) evanescent microwave probe SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID MICROSCOPE AB In this article we describe evanescent field imaging of material nonuniformities with a record resolution of 0.4 mm at 1 GHz (lambda g/750 000), using a resonant stripline scanning microwave probe. A chemically etched tip is used as a point-like evanescent field emitter and a probe-sample distance modulation is employed to improve the signal-to-noise ratio. Images obtained by evanescent microwave probe, by optical microscope, and by scanning tunneling microscope are presented for comparison. Probe was calibrated to perform quantitative conductivity measurements. The principal factors affecting the ultimate resolution of evanescent microwave probe are also discussed. (C) 1999 American Institute of Physics. [S0034-6748(99)03603-5]. C1 Case Western Reserve Univ, Cleveland, OH 44106 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NASA, Lewis Res Ctr, Cleveland, OH 44135 USA. RP Tabib-Azar, M (reprint author), Case Western Reserve Univ, Cleveland, OH 44106 USA. EM mxt7@po.cwru.edu NR 5 TC 84 Z9 86 U1 3 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAR PY 1999 VL 70 IS 3 BP 1725 EP 1729 DI 10.1063/1.1149658 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 174AN UT WOS:000079012100023 ER PT J AU Gidvani, VK Bhowmick, SK AF Gidvani, VK Bhowmick, SK TI Midline posterior cervical cystic hygroma SO SOUTHERN MEDICAL JOURNAL LA English DT Article ID LYMPHANGIOMA AB Cystic hygromas are among the most common congenital neck masses. They have a predilection for the left posterior triangle and manifest early in life. Although various locations of cystic hygromas are found in the literature, we believe our case of a 9-month-old girl represents the first reported occurrence of a posterior cervical midline cystic hygroma. C1 USAF, Med Ctr Keesler, Dept Pediat, Keesler AFB, MS 39534 USA. RP Gidvani, VK (reprint author), USAF, Med Ctr Keesler, Dept Pediat, 302 Fisher St,Rm 1A132, Keesler AFB, MS 39534 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU SOUTHERN MEDICAL ASSN PI BIRMINGHAM PA 35 LAKESHORE DR PO BOX 190088, BIRMINGHAM, AL 35219 USA SN 0038-4348 J9 SOUTHERN MED J JI South.Med.J. PD MAR PY 1999 VL 92 IS 3 BP 340 EP 343 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 177GZ UT WOS:000079203400019 PM 10094282 ER PT J AU Eggers, J Channel, S Graeter, L Johnson, P MacMahon, K Sudberry, G Warren, A Latendresse, J AF Eggers, J Channel, S Graeter, L Johnson, P MacMahon, K Sudberry, G Warren, A Latendresse, J TI Use of hematoxylin stain to enhance evaluation of heart malformations in the fetal rat SO TERATOLOGY LA English DT Article AB Fresh and formalin fixed visceral microdissection techniques are valuable tools for studying cardiac teratology in the fetal rat, but are limited by the difficulty experienced in visualizing the minute structures needing to be evaluated. This paper describes a simple and quick staining technique used to enhance the examination procedure. A hematoxylin-saline mixture applied directly on endothelial-lined surfaces of the heart at different stages during microdissection greatly improved visualization of membrane-thin structures such as the pulmonary and aortic semilunar valves, right- and left-side atrioventricular valves, and atrial and ventricular septa. Hematoxylin staining of endocardial surfaces is a useful adjunct to the standard visceral microdissection technique. (C) 1999 Wiley-Liss, Inc. C1 USAF, Res Lab, Operat Toxicol Branch, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Eggers, J (reprint author), DVM, 552 Graham, San Antonio, TX 78234 USA. NR 6 TC 3 Z9 3 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0040-3709 J9 TERATOLOGY JI Teratology PD MAR PY 1999 VL 59 IS 3 BP 173 EP 175 DI 10.1002/(SICI)1096-9926(199903)59:3<173::AID-TERA9>3.0.CO;2-2 PG 3 WC Developmental Biology; Toxicology SC Developmental Biology; Toxicology GA 181WN UT WOS:000079466100008 PM 10194808 ER PT J AU Huang, JQ Goltz, MN AF Huang, JQ Goltz, MN TI Solutions to equations incorporating the effect of rate-limited contaminant mass transfer on vadose zone remediation by soil vapor extraction SO WATER RESOURCES RESEARCH LA English DT Article ID UNSATURATED SOILS; POROUS-MEDIA; TRANSPORT AB Soil vapor extraction (SVE) is a technique that is frequently used to remediate unsaturated soils in the vadose zone that are contaminated with volatile organic compounds. Laboratory research and field experience have demonstrated that rate-limited mass transfer of a contaminant from aquifer solids and soil water to the gas phase significantly impacts the efficacy and speed of the remediation. An exact analytical solution to equations describing SVE controlled by rate-limited mass transfer is presented. Processes modeled include contaminant advective-dispersive transport in a gas phase converging on an extraction well and rate-limited mass transfer of dissolved and sorbed contaminants into the gas phase, with the rate limitation modeled assuming first-order kinetics. In addition to the exact solution an approximate solution, as well as an exact solution for plug flow (no dispersion), is presented. These analytical solutions may be useful in verifying numerical codes that are being developed to model SVE of volatile organic compounds. C1 USAF, Inst Technol, Grad Sch Engn, Dept Engn & Environm Management, Wright Patterson AFB, OH 45433 USA. RP Huang, JQ (reprint author), USAF, Inst Technol, Grad Sch Engn, Dept Engn & Environm Management, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. RI Goltz, Mark/A-7394-2009; OI Goltz, Mark/0000-0003-3601-6453 NR 14 TC 7 Z9 8 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAR PY 1999 VL 35 IS 3 BP 879 EP 883 DI 10.1029/1998WR900113 PG 5 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 169WG UT WOS:000078771700024 ER PT J AU Mather, PT Jeon, HG Romo-Uribe, A Haddad, TS Lichtenhan, JD AF Mather, PT Jeon, HG Romo-Uribe, A Haddad, TS Lichtenhan, JD TI Mechanical relaxation and microstructure of poly(norbornyl-POSS) copolymers SO MACROMOLECULES LA English DT Article ID NYLON 6-CLAY HYBRID; SILOXANE COPOLYMERS; POLYMERS; SILSESQUIOXANES AB The mechanical relaxation behavior and microstructure of a series of novel norbornyl-POSS organic-inorganic copolymers have been investigated. We have examined the influence on physical properties of both the weight, fraction of POSS-norbornyl monomer and the corner group composition. POSS. refers to the polyhedral oligomeric silsesquioxane inorganic/organic macromer, which is composed of an inorganic Si8O12 spherical core surrounded by seven inert organic corner groups and one reactive norbornyl moiety, It was observed that POSS copolymerization enhances the cr-relaxation temperature, T-alpha, in proportion to the weight fraction of the POSS-norbornyl comonomer. Interestingly, however, the magnitude of this this dependence is larger for the POSS-norbornyl comonomer possessing cyclohexyl corner groups (CyPOSS) than for the copolymer with cyclopentyl corner groups (CpPOSS). Although POSS copolymerization yields only slight enhancement of the room temperature storage modulus, at temperatures lower than a strong mechanical relaxation, identified as a beta-relaxation, and near T = -78 degrees C, there isa significant POSS reinforcement of the storage modulus, The position of the beta relaxation observed in the CyPOSS series of copolymers is Independent of POSS weight fraction, and the frequency dependence of this peak position yields the activation energy, Delta H-beta = 14.7 (liberation of motion of the cyclohexyl corner groups). A similar effect is observed, to some extent, for the CpPOSS copolymers, although only part of Be relaxation is observed. X-rag scattering shows that, the CyPOSS copolymerization preserves the amorphous character of the polynorbornene homopolymer but CpPOSS copolymerization leads to significant ordering of the POSS macromers. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL MLBP, Wright Patterson AFB, OH 45433 USA. Systran Corp, Wright Patterson AFB, OH 45433 USA. Raytheon STX, Edwards AFB, CA 93524 USA. USAF, Res Lab, Propuls Directorate, AFRL PRSM, Edwards AFB, CA 93524 USA. RP Mather, PT (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL MLBP, 2941 P St, Wright Patterson AFB, OH 45433 USA. NR 21 TC 323 Z9 338 U1 9 U2 95 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD FEB 23 PY 1999 VL 32 IS 4 BP 1194 EP 1203 DI 10.1021/ma981210n PG 10 WC Polymer Science SC Polymer Science GA 170KK UT WOS:000078804700032 ER PT J AU Beranek, MW Chan, EY Hager, HE Le, QN Wilgus, JS AF Beranek, MW Chan, EY Hager, HE Le, QN Wilgus, JS TI Emerging opportunities for applying COTS optoelectronics in avionics fiber-optic networks SO MICROPROCESSORS AND MICROSYSTEMS LA English DT Article DE Air Force F-22; avionics networks; Boeing 777; chip-on-board; diode lasers; fiber-optic networks; optoelectronics; reliability with hermeticity; silicon optical bench ID HUMIDITY-BIAS-BEHAVIOR; QUANTUM-WELL LASERS; RELIABILITY; OPERATION; CORROSION; MODULES; DEVICES; VCSELS AB Current avionics fiber-optic networks utilize light-emitting diode (LED)-based transmitter optical sources owing to their established high reliability over the commercial and military avionics temperature regimes. One shortcoming of LED-based transmitters is the limited modulation speed and low output power of the LED devices. Recently published high temperature reliability data on commercial-off-the-shelf (COTS) diode lasers appears promising for realizing higher speed(i.e. > 1 Gb/s) optical interconnects in avionics systems. Although ruggedized hermetic packaging has been developed for avionics optoelectronic modules, the application of newer generation commercial sector packaging to reduce optoelectronic module production costs is under examination. 'Glob-top' sealed chip-on-board, passive alignment silicon micro-optical bench, and non-hennetic laser and detector packaging technologies offer potential cost-reductions in avionics optoelectronic modules. However, the reliability of these new laser sources and packaging options has yet to be thoroughly evaluated for the harsh commercial and military avionics environment. (C) 1999 Published by Elsevier Science B.V. C1 USAF, Res Lab, Wright Patterson AFB, Dayton, OH 45433 USA. Boeing Co, Seattle, WA 98124 USA. RP Wilgus, JS (reprint author), USAF, Res Lab, Wright Patterson AFB, 9185 Avion Circle, Dayton, OH 45433 USA. NR 48 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0141-9331 EI 1872-9436 J9 MICROPROCESS MICROSY JI Microprocess. Microsyst. PD FEB 22 PY 1999 VL 22 IS 8 BP 439 EP 451 DI 10.1016/S0141-9331(98)00103-3 PG 13 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 174HV UT WOS:000079029400003 ER PT J AU Galejs, LE Kass, EJ AF Galejs, LE Kass, EJ TI Diagnosis and treatment of the acute scrotum SO AMERICAN FAMILY PHYSICIAN LA English DT Article ID DOPPLER ULTRASONOGRAPHY; CREMASTERIC REFLEX; EPIDIDYMITIS; MANAGEMENT; CHILDREN; TORSION; BOYS AB Testicular torsion must be considered in any patient who complains of acute scrotal pain and swelling. Torsion of the testis is a surgical emergency because the likelihood of testicular salvage decreases as the duration of torsion increases. Conditions that may mimic testicular torsion, such as torsion of a testicular appendage, epididymitis, trauma, hernia, hydrocele, varicocele and Schonlein-Henoch purpura, generally do not require immediate surgical intervention. The cause of an acute scrotum can usually be established based on a careful history, a thorough physical examination and appropriate diagnostic tests. The onset, character and severity of symptoms must be determined. The physical examination should include inspection and palpation of the abdomen, testis, epididymis, scrotum and inguinal region. Urinalysis should always be performed, but scrotal imaging is necessary only when the diagnosis remains unclear Once the correct diagnosis is established, treatment is usually straightforward. C1 William Beaumont Hosp, Royal Oak, MI 48073 USA. USAF, Med Ctr, Dayton, OH USA. RP Galejs, LE (reprint author), William Beaumont Hosp, 3535 W 13 Mile Rd,Suite 438, Royal Oak, MI 48073 USA. NR 15 TC 10 Z9 12 U1 0 U2 1 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD FEB 15 PY 1999 VL 59 IS 4 BP 817 EP 824 PG 8 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 170MQ UT WOS:000078809800011 PM 10068706 ER PT J AU Harris, MD Siegel, LB Alloway, JA AF Harris, MD Siegel, LB Alloway, JA TI Gout and hyperuricemia SO AMERICAN FAMILY PHYSICIAN LA English DT Article ID NONSTEROIDAL ANTIINFLAMMATORY DRUGS; ADRENOCORTICOTROPIC HORMONE; TRIAMCINOLONE ACETONIDE; ARTHRITIS; INDOMETHACIN; GUIDELINES; PREVALENCE; TOXICITY; URATE AB Gout is a condition characterized by the deposition of monosodium urate crystals in the joints or soft tissue. The four phases of gout include asymptomatic hyperuricemia, acute gouty arthritis, intercritical gout and chronic tophaceous gout. The peak incidence occurs in patients 30 to 50 years old, and the condition is much more common in men than in women. Patients with asymptomatic hyperuricemia do not require treatment, but efforts should be made to lower their urate levels by encouraging them to make changes in diet or lifestyle. Acute gout most commonly affects the first metatarsal joint of the foot, but other joints are also commonly involved. Definitive diagnosis requires joint aspiration with demonstration of birefringent crystals in the synovial fluid under a polarized light microscope. Treatment includes nonsteroidal anti-inflammatory drugs.(NSAIDs). colchicine, corticosteroids and analgesics. In patients without complications, NSAID therapy is preferred. C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Finch Univ Hlth Sci Chicago Med Sch, Chicago, IL USA. RP Harris, MD (reprint author), Wilford Hall USAF Med Ctr, 59 MWIPSMJ,2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 33 TC 122 Z9 127 U1 11 U2 20 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD FEB 15 PY 1999 VL 59 IS 4 BP 925 EP 934 PG 10 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 170MQ UT WOS:000078809800019 PM 10068714 ER PT J AU Carlson, JL AF Carlson, JL TI The Greater Evergreen area guide including the communities: Bailey, Conifer, Evergreen, Genesee, Indian Hills, Kittredge, Lookout Mountain, Morrison, and Pine. SO LIBRARY JOURNAL LA English DT Book Review C1 Vandenberg AFB Lib, Vandenberg AFB, CA 93437 USA. RP Carlson, JL (reprint author), Vandenberg AFB Lib, Vandenberg AFB, CA 93437 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD FEB 15 PY 1999 VL 124 IS 3 BP 174 EP 174 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 166CR UT WOS:000078559100186 ER PT J AU Sudarshanam, VS Cronin-Golomb, M Hemmer, PR Shahriar, MS AF Sudarshanam, VS Cronin-Golomb, M Hemmer, PR Shahriar, MS TI Raman phase conjugate resonator for intracavity aero-optic turbulence aberration correction SO OPTICS COMMUNICATIONS LA English DT Article DE phase conjugate resonator; optical phase conjugation; coherent population trapping; degenerate four-wave mixing; turbulence aberration correction ID SELF-OSCILLATION; SODIUM; VAPOR; MODES; GAIN AB A cw degenerate phase conjugate resonator (PCR) with intracavity aero-optic turbulent flow is demonstrated using sodium vapor pumped with a low intensity cw laser. A turbulent helium jet at a high flow velocity of 250 m/s and forcing frequency of 18 kHz generated the spatio-temporal aberrations. The intracavity normalized peak-to-peak intensity fluctuations at 18 kHz measured with a pinhole-detector are ten times smaller in the corrected beam than in the aberrated beam. The threshold pump intensity for the resonator is similar to 4.5 W/cm(2) in the absence of the turbulent flow. The pump frequency is tuned well within the Doppler width of the Na D-1 transition. Evidence of a degenerate (laboratory frame) double-Lambda mechanism involving Zeeman sublevels is also shown. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Tufts Univ, Ctr Electroopt Technol, Medford, MA 02155 USA. USAF, Res Lab, Sensors Directorate, Bedford, MA 01731 USA. MIT, Elect Res Lab, Cambridge, MA 02139 USA. RP Sudarshanam, VS (reprint author), Tufts Univ, Ctr Electroopt Technol, 4 Colby St, Medford, MA 02155 USA. EM sudar@mit.edu RI Shahriar, Selim/B-7270-2009; Cronin-Golomb, Mark/A-5430-2012 OI Cronin-Golomb, Mark/0000-0002-8936-4358 NR 14 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD FEB 15 PY 1999 VL 160 IS 4-6 BP 283 EP 288 DI 10.1016/S0030-4018(98)00679-8 PG 6 WC Optics SC Optics GA 173JZ UT WOS:000078978600018 ER PT J AU Crisman, EE Derov, JS Carr, PH Mittleman, SD Liu, DDW AF Crisman, EE Derov, JS Carr, PH Mittleman, SD Liu, DDW TI Two-element dielectric antenna serially excited by optical wavelength multiplexing SO OPTICS LETTERS LA English DT Article ID PULSES AB A single pulsed laser beam containing multiple wavelengths (wavelength multiplexing) is employed to activate two semiconductor antennas in series. The dielectric nature of the semiconductors permits serial cascading of the antenna elements. Recently observed nonlinear characteristics of the radiated field as a function of the free carrier accelerating (bias) voltage are used to minimize the small interactions between elements. We demonstrate that the temporal electromagnetic radiation distribution of two serial antennas is sensitive to the three-dimensional pattern of the optical excitation source. One can, in turn, vary this distribution continuously by optical means to reconfigure the array. (C) 1999 Optical Society of America. OCIS codes: 160.5140, 260.5150, 140.0140, 060.4230, 350.4010. C1 USAF, Div Electromagnet Technol, AFRL, SNHA, Hanscom AFB, MA 01731 USA. Sanders, Adv Technol Div, Nashua, NH 03061 USA. RP Crisman, EE (reprint author), Brown Univ, Dept Phys, Box 1843, Providence, RI 02912 USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD FEB 15 PY 1999 VL 24 IS 4 BP 235 EP 237 DI 10.1364/OL.24.000235 PG 3 WC Optics SC Optics GA 168EZ UT WOS:000078679700017 PM 18071465 ER PT J AU Presilla-Marquez, JD Harper, J Sheehy, JA Carrick, PG Larson, CW AF Presilla-Marquez, JD Harper, J Sheehy, JA Carrick, PG Larson, CW TI Vibrational spectra of cyclic C-8 in solid argon SO CHEMICAL PHYSICS LETTERS LA English DT Article; Proceedings Paper CT 52nd Ohio State University International Symposium on Molecular Spectroscopy CY JUN 16-20, 1997 CL COLUMBUS, OH SP Ohio State Univ ID DENSITY-FUNCTIONAL THEORY; SMALL CARBON CLUSTERS; INFRARED-SPECTROSCOPY; EXACT EXCHANGE; NEON MATRICES; MOLECULES; CHAINS; AR AB Vapors from solid and powdered carbon, emitted from an oven cycled between 2000 and 3000 K, were co-condensed with argon onto a CsI substrate maintained at 10 K. The cycling process produced a multilayered matrix with regions of high carbon density alternating with layers of argon. FTIR measurements including C-13 isotopic data, supported by ab initio calculations, allow the assignment of a band observed at 1817.8 cm(-1) to the nu(12)(e(u)) fundamental of cyclic C-8. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USAF, Prop Sci & Adv Concepts Div, Res Lab, PRS, Edwards AFB, CA 93524 USA. RP Sheehy, JA (reprint author), USAF, Prop Sci & Adv Concepts Div, Res Lab, PRS, 10 E Saturn Blvd, Edwards AFB, CA 93524 USA. EM jeff.sheehy@ple.af.mil NR 22 TC 16 Z9 16 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD FEB 12 PY 1999 VL 300 IS 5-6 BP 719 EP 726 DI 10.1016/S0009-2614(98)01409-2 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 166BE UT WOS:000078555700032 ER PT J AU Hoge, B Christe, KO AF Hoge, B Christe, KO TI A convenient synthesis of carbonyl chloride fluoride SO JOURNAL OF FLUORINE CHEMISTRY LA English DT Article DE carbonyl chloride fluoride; carbonyl chloride antimony pentafluoride adduct; synthesis AB An improved method for the synthesis of COClF under mild conditions is reported. Pure COClF can be isolated in essentially quantitative yield from the decomposition of the oxygen-bridged COCl2. SbF5 donor-acceptor adduct at room temperature in a dynamic vacuum. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. USAF, Res Lab, Edwards AFB, CA 93524 USA. RP Christe, KO (reprint author), Univ So Calif, Loker Hydrocarbon Res Inst, Univ Pk, Los Angeles, CA 90089 USA. RI Christe, Karl/O-4885-2014; Hoge, Berthold/A-4051-2015 OI Christe, Karl/0000-0003-0661-5519; NR 14 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-1139 J9 J FLUORINE CHEM JI J. Fluor. Chem. PD FEB 11 PY 1999 VL 94 IS 1 BP 107 EP 108 DI 10.1016/S0022-1139(98)00359-5 PG 2 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 176GD UT WOS:000079142300019 ER PT J AU Evans, BL Martin, JB Roggemann, MC AF Evans, BL Martin, JB Roggemann, MC TI Deconvolution of shift-variant broadening for Compton scatter imaging SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 9th Symposium on Radiation Measurements and Applications CY MAY 11-14, 1998 CL ANN ARBOR, MICHIGAN DE Compton scatter imaging technique; Doppler broadening; deconvolution; gamma rays AB A technique is presented for deconvolving shift-variant Doppler broadening of singly Compton scattered gamma rays from their recorded energy distribution. Doppler broadening is important in Compton scatter imaging techniques employing gamma rays with energies below roughly 100 keV. The deconvolution unfolds an approximation to the angular distribution of scattered photons from their recorded energy distribution in the presence of statistical noise and background counts. Two unfolding methods are presented, one based on a least-squares algorithm and one based on a maximum likelihood algorithm. Angular distributions unfolded from measurements made on small scattering targets show less evidence of Compton broadening. This deconvolution is shown to improve the quality of filtered backprojection images in multiplexed Compton scatter tomography. Improved sharpness and contrast are evident in the images constructed from unfolded signals. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. Michigan Technol Univ, Dept Elect Engn, Houghton, MI 49931 USA. RP Evans, BL (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 14 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD FEB 11 PY 1999 VL 422 IS 1-3 BP 661 EP 666 DI 10.1016/S0168-9002(98)01013-4 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 171MY UT WOS:000078868800129 ER PT J AU Hayat, MM Torres, SN Armstrong, E Cain, SC Yasuda, B AF Hayat, MM Torres, SN Armstrong, E Cain, SC Yasuda, B TI Statistical algorithm for nonuniformity correction in focal-plane arrays SO APPLIED OPTICS LA English DT Article AB A statistical algorithm has been developed to compensate for the fixed-pattern noise associated with spatial nonuniformity and temporal drift in the response of focal-plane array infrared imaging systems. The algorithm uses initial scene data to generate initial estimates of the gain, the offset, and the variance of the additive electronic noise of each detector element. The algorithm then updates these parameters by use of subsequent frames and uses the updated parameters to restore the true image by use of a least-mean-square error finite-impulse-response filter. The algorithm is applied to infrared data, and the restored images compare favorably with those restored by use of a multiple-point calibration technique. (C) 1999 Optical Society of America. C1 Univ Dayton, Grad Program Electroopt, Dayton, OH 45468 USA. Univ Dayton, Dept Elect & Comp Engn, Dayton, OH 45468 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Hayat, MM (reprint author), Univ Dayton, Grad Program Electroopt, Dayton, OH 45468 USA. EM mhayat@engr.udayton.edu; storres@flyernet.udayton.edu; armstree@aa.wpafb.af.mil; sccain@ibm.net RI Hayat, Majeed/E-4924-2010; Optica y Fotonica, Centro/I-4347-2015 NR 14 TC 89 Z9 117 U1 2 U2 14 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD FEB 10 PY 1999 VL 38 IS 5 BP 772 EP 780 DI 10.1364/AO.38.000772 PG 9 WC Optics SC Optics GA 166AB UT WOS:000078553100005 PM 18305675 ER PT J AU de Rege, FM Kassebaum, JD Scott, BL Abney, KD Balaich, GJ AF de Rege, FM Kassebaum, JD Scott, BL Abney, KD Balaich, GJ TI Synthesis, structure, and reactivity of 1,2-(1 ',1 ',2 ',2 '-tetramethyldisilane-1 ',2 ')carborane SO INORGANIC CHEMISTRY LA English DT Article ID CARBON UNSATURATED-COMPOUNDS; 2-ATOM INSERTION REACTIONS; POLYSILANE HIGH POLYMERS; SI; HEXAMETHYLSILIRANE; POLYMERIZATION; ACETYLENES; CONVERSION; METATHESIS; CHEMISTRY AB The novel strained compound 1,2-(1',1',2',2'-tetramethyldisilane-1',2')carborane (1) was synthesized by the reaction of 1,2-dilithiocarborane and dichlorotetramethyldisilane. Compound 1 was characterized by solution methods and its structure determined by single-crystal X-ray diffraction. In contrast to its organic analogue o-(disilanyl)-phenylene, the reaction of 1 with ethanol leads to cleavage of a Si-C bond rather than a Si-Si bend. Similarly to other cyclic disilanes, exposure of a solution of I to oxygen leads to the insertion of an oxygen atom into the Si-Si bond. The structure of the oxygen inserted product was also determined by X-ray crystallography. The general chemistry and attempts at polymerizing 1 are briefly discussed. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. USAF Acad, Dept Chem, Chem Res Ctr, Colorado Springs, CO 80840 USA. RP de Rege, FM (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, CST-11,Mail Stop J514, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017; OI Scott, Brian/0000-0003-0468-5396; de Rege, Francis/0000-0003-0013-5856 NR 37 TC 11 Z9 11 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD FEB 8 PY 1999 VL 38 IS 3 BP 486 EP 489 DI 10.1021/ic980992y PG 4 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 167DE UT WOS:000078616700014 ER PT J AU Hohl, A Gavrielides, A AF Hohl, A Gavrielides, A TI Bifurcation cascade in a semiconductor laser subject to optical feedback SO PHYSICAL REVIEW LETTERS LA English DT Article ID COHERENCE COLLAPSE; DIODE-LASERS; NOISE; MODE AB We investigated a single mode semiconductor laser system pumped near threshold and subject to optical feedback from a short distance. We found both experimentally and numerically that as the feedback strength is increased the laser undergoes a cascade of bifurcations as one external cavity mode becomes unstable and the next one with higher intensity becomes stable only to be destabilized and replaced by the next stable external cavity mode. In the stable regions the laser operates in the so-called maximum gain mode and the unstable regions exhibit chaos which evolves into low-frequency fluctuations characterized by intensity dropouts. [S0031-9007(98)08369-0]. C1 USAF, Res Lab, DELO, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. RP Hohl, A (reprint author), USAF, Res Lab, DELO, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. NR 15 TC 72 Z9 72 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 8 PY 1999 VL 82 IS 6 BP 1148 EP 1151 DI 10.1103/PhysRevLett.82.1148 PG 4 WC Physics, Multidisciplinary SC Physics GA 164HV UT WOS:000078458500018 ER PT J AU Look, DC Sizelove, JR AF Look, DC Sizelove, JR TI Dislocation scattering in GaN SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIFFRACTION AB A theory of charged-dislocation-line scattering is developed within the framework of the Boltzmann transport equation. A fit of the theory to temperature-dependent Hall-effect data in GaN gives dislocation densities which are in excellent agreement with those measured by transmission electron microscopy. This work shows that threading edge dislocations in GaN indeed are electrically active, in agreement with recent theoretical predictions. [S0031-9007(98)08378-1]. C1 Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Look, DC (reprint author), Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. NR 23 TC 345 Z9 347 U1 8 U2 52 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD FEB 8 PY 1999 VL 82 IS 6 BP 1237 EP 1240 DI 10.1103/PhysRevLett.82.1237 PG 4 WC Physics, Multidisciplinary SC Physics GA 164HV UT WOS:000078458500040 ER PT J AU Panetta, CA Kumpaty, HJ Heimer, NE Leavy, MC Hussey, CL AF Panetta, CA Kumpaty, HJ Heimer, NE Leavy, MC Hussey, CL TI Disulfide-Functionalized 3-, 4-, 5-, and 6-substituted 2,2 '-bipyridines and their ruthenium complexes SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID GOLD; MONOLAYERS; ELECTRODES C1 Univ Mississippi, Dept Chem, University, MS 38677 USA. Univ Wisconsin, Dept Chem, Whitewater, WI 53190 USA. USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. RP Panetta, CA (reprint author), Univ Mississippi, Dept Chem, University, MS 38677 USA. NR 20 TC 30 Z9 31 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD FEB 5 PY 1999 VL 64 IS 3 BP 1015 EP 1021 DI 10.1021/jo9814795 PG 7 WC Chemistry, Organic SC Chemistry GA 165XY UT WOS:000078548200055 ER PT J AU Hutson, A John, R Jira, J AF Hutson, A John, R Jira, J TI Effect of temperature on fiber/matrix interface sliding stress in SCS-6/TIMETAL (R) 21S SO SCRIPTA MATERIALIA LA English DT Article ID FATIGUE-CRACK-GROWTH; FIBROUS COMPOSITES; MATRIX COMPOSITE; FIBER COMPOSITES; MECHANICS C1 USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Struct Integr Div, Adv Mat Characterizat Grp, Dayton, OH 45469 USA. RP Hutson, A (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. NR 27 TC 11 Z9 11 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD FEB 5 PY 1999 VL 40 IS 5 BP 529 EP 535 DI 10.1016/S1359-6462(98)00463-1 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 177CK UT WOS:000079189700003 ER PT J AU Carlisle, MC AF Carlisle, MC TI SIGPLAN Notices on language evolution SO ACM SIGPLAN NOTICES LA English DT Letter C1 USAF, Washington, DC 20330 USA. RP Carlisle, MC (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 0362-1340 J9 ACM SIGPLAN NOTICES JI ACM Sigplan Not. PD FEB PY 1999 VL 34 IS 2 BP 41 EP 41 PG 1 WC Computer Science, Software Engineering SC Computer Science GA 183KV UT WOS:000079553500008 ER PT J AU Crossley, WA Cook, AM Fanjoy, DW Venkayya, VB AF Crossley, WA Cook, AM Fanjoy, DW Venkayya, VB TI Using the two-branch tournament genetic algorithm for multiobjective design SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 39th Structures, Structural Dynamics, and Materials Conference CY APR 20-23, 1998 CL LONG BEACH, CALIFORNIA SP Amer Inst Aeronaut & Astronaut, ASME, ASCE, AHS, ASC AB The two-branch tournament genetic algorithm is presented as an approach to determine a set of Pareto-optimal solutions to multiobjective design problems. Because the genetic algorithm searches using a population of points rather than using a point-to-point search, it is possible to generate a large number of solutions to multiobjective problems in a single run of the algorithm. The two-branch tournament and its implementation in a genetic algorithm (GA) to provide these solutions are discussed. This approach differs from most traditional methods for GA-based multiobjective design; it does not require the nondominated ranking approach nor does it require additional fitness manipulations. A multiobjective mathematical benchmark problem and a 10-bar truss problem were solved to illustrate how this approach works for typical multiobjective problems. These problems also allowed comparison to published solutions. The two-branch GA was also applied to a problem combining discrete and continuous variables to illustrate an additional advantage of this approach for multiobjective design problems. Results of all three problems were compared to those of single-objective approaches providing a measure of how closely the Pareto-optimal set is estimated by the two-branch GA. Finally, conclusions were made about the benefits and potential for improvement of this approach. C1 Purdue Univ, Sch Aeronaut & Astronaut, W Lafayette, IN 47907 USA. USAF, Res Lab, Struct Div, Wright Patterson AFB, OH 45433 USA. RP Crossley, WA (reprint author), Purdue Univ, Sch Aeronaut & Astronaut, 1282 Grissom Hall, W Lafayette, IN 47907 USA. NR 14 TC 31 Z9 35 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD FEB PY 1999 VL 37 IS 2 BP 261 EP 267 DI 10.2514/2.699 PG 7 WC Engineering, Aerospace SC Engineering GA 166BU UT WOS:000078557000017 ER PT J AU Ross, GK De Jong, CMJ AF Ross, GK De Jong, CMJ TI Pericardial tamponade SO AMERICAN JOURNAL OF NURSING LA English DT Article C1 Wilford Hall USAF Med Ctr, Emergency Dept, San Antonio, TX 78236 USA. Wilford Hall USAF Med Ctr, Coronary Care Unit, San Antonio, TX 78236 USA. RP Ross, GK (reprint author), Wilford Hall USAF Med Ctr, Emergency Dept, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0002-936X J9 AM J NURS JI Am. J. Nurs. PD FEB PY 1999 VL 99 IS 2 BP 35 EP 35 PG 1 WC Nursing SC Nursing GA 166LZ UT WOS:000078579200011 PM 10036569 ER PT J AU Clarke, CS Harlin, SA AF Clarke, CS Harlin, SA TI Puerperal ovarian vein thrombosis with extension into the inferior vena cava SO AMERICAN SURGEON LA English DT Article; Proceedings Paper CT 66th Annual Meeting of the Southeastern-Surgical-Congress CY JAN 31-FEB 04, 1998 CL ATLANTA, GEORGIA SP SE Surg Congress ID THROMBOPHLEBITIS AB The incidence of puerperal ovarian vein thrombosis is estimated to range between 1 in 600 and 1 in 2000 deliveries. The cardinal signs of puerperal ovarian vein thrombosis include fever, leukocytosis, and right lower quadrant abdominal pain, most often in a recently delivered female patient. These patients are classically described as failing to improve with intravenous antibiotic therapy alone; resolution of symptoms and presumptive diagnosis is made on defervescence with the addition of intravenous heparin therapy. Objective diagnostic modalities include venography, ultrasound, laparoscopy, and MRI, although CT remains the gold standard for the identification of this underdiagnosed entity. We present a case report of a 20-year-old female treated at our facility for puerperal ovarian vein thrombosis. She was transferred to our vascular surgery service after developing the classic signs of puerperal ovarian vein thrombosis and undergoing CT demonstrating ovarian vein thrombosis with extension of free-floating thrombus into her inferior vena cava (IVC). This degree of thrombosis was particularly concerning when one considers the 3 to 33 per cent rate of pulmonary embolism reported in patients with puerperal ovarian vein thrombosis. Treatment modalities for such extensive degrees of thrombosis are described in the literature and range from hysterectomy and thrombectomy to ligation of the IVC, In our case, we prophylactically placed a suprarenal IVC Greenfield filter to protect against pulmonary embolism and proceeded with the standard regimen of anticoagulation and antibiotics. This treatment approach has been reported only twice previously in the literature, to our knowledge. C1 81st Med Grp, Keesler AFB, MS USA. RP Clarke, CS (reprint author), 781 MDOS-SGCQ,301 Fisher St,1A132, Keesler AFB, MS 39534 USA. NR 9 TC 12 Z9 12 U1 0 U2 0 PU SOUTHEASTERN SURGICAL CONGRESS PI ATLANTA PA 141 WEST WIEUCA RD, STE B100, ATLANTA, GA 30342 USA SN 0003-1348 J9 AM SURGEON JI Am. Surg. PD FEB PY 1999 VL 65 IS 2 BP 147 EP 150 PG 4 WC Surgery SC Surgery GA 160QU UT WOS:000078243100012 PM 9926750 ER PT J AU Edell, T Gingrich, T Zhao, W Jones, D AF Edell, T Gingrich, T Zhao, W Jones, D TI Enhanced NMDA-induced [H-3]NE release in allodynic rat spinal cord slices SO ANESTHESIA AND ANALGESIA LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Dept Anesthesiol, Lackland AFB, TX 78236 USA. Univ Texas, Hlth Sci Ctr, Dept Anesthesiol, San Antonio, TX 78284 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0003-2999 J9 ANESTH ANALG JI Anesth. Analg. PD FEB PY 1999 VL 88 IS 2 SU S MA S207 PG 1 WC Anesthesiology SC Anesthesiology GA 165EN UT WOS:000078507400207 ER PT J AU Vogel, A Noack, J Nahen, K Theisen, D Busch, S Parlitz, U Hammer, DX Noojin, GD Rockwell, BA Birngruber, R AF Vogel, A Noack, J Nahen, K Theisen, D Busch, S Parlitz, U Hammer, DX Noojin, GD Rockwell, BA Birngruber, R TI Energy balance of optical breakdown in water at nanosecond to femtosecond time scales SO APPLIED PHYSICS B-LASERS AND OPTICS LA English DT Article ID LASER-INDUCED BREAKDOWN; ACOUSTIC TRANSIENT GENERATION; NONLINEAR ABSORPTION; PLASMA FORMATION; AQUEOUS-MEDIA; ABLATION; PULSES; PICOSECOND; BUBBLE; SPECTROSCOPY AB During optical breakdown, the energy delivered to the sample is either transmitted, reflected, scattered, or absorbed. Pathways for the division of the absorbed energy are the evaporation of the focal volume, the plasma radiation, and the mechanical effects such as shock wave emission and cavitation. The partition of laser energy between these channels during breakdown in water was investigated for four selected laser parameters typical for intraocular microsurgery (6-ns pulses of 1 and 10 mJ focused at an angle of 22 degrees, and 30-ps pulses of 50 mu J and 1 mJ focused at 14 degrees, all at 1064 nm). Scattering and reflection were found to be small compared to transmission and absorption during optical breakdown. The ratio of the shock wave energy and cavitation bubble energy was approximately constant (between 1.5:1 and 2:1). These results allowed us to perform a more comprehensive study of the influence of pulse duration (100 fs-76 ns) and focusing angle (4 degrees-32 degrees) on the energy partition by measuring only the plasma transmission and the cavitation bubble energy. The bubble energy was used as an indicator for the total amount of mechanical energy. We found that the absorption at the breakdown site first decreases strongly with decreasing pulse duration, but increases again for tau < 3 ps. The conversion of the absorbed energy into mechanical energy is approximate to 90% with ns pulses at large focusing angles. It decreases both with decreasing focusing angle and pulse duration (to < 15% for fs pulses). The disruptive character of plasma-mediated laser effects is therefore strongly reduced when ultrashort laser pulses are used. C1 Med Laserzentrum Lubeck, D-23562 Lubeck, Germany. Univ Gottingen, Drittes Phys Inst, D-37073 Gottingen, Germany. USAF, Res Lab, Brooks AFB, TX 78235 USA. RP Vogel, A (reprint author), Med Laserzentrum Lubeck, Peter Monnik Weg 4, D-23562 Lubeck, Germany. EM vogel@mll.mu-luebeck.de; ulli@physik3.gwdg.de; ben.rockwell@hedo.brooks.af.mil RI Vogel, Alfred/D-9852-2011; Birngruber, Reginald/Q-2342-2016 NR 42 TC 272 Z9 299 U1 10 U2 71 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0946-2171 J9 APPL PHYS B-LASERS O JI Appl. Phys. B-Lasers Opt. PD FEB PY 1999 VL 68 IS 2 BP 271 EP 280 DI 10.1007/s003400050617 PG 10 WC Optics; Physics, Applied SC Optics; Physics GA 162MD UT WOS:000078349900018 ER PT J AU Debray, P Raichev, OE Rahman, M Akis, R Mitchel, WC AF Debray, P Raichev, OE Rahman, M Akis, R Mitchel, WC TI Ballistic transport of electrons in T-shaped quantum waveguides SO APPLIED PHYSICS LETTERS LA English DT Article ID WEAK MAGNETIC-FIELDS; CONDUCTANCE FLUCTUATIONS; STATES; DOT; TRANSISTOR AB Ballistic transport of electrons through T-shaped quantum waveguides with stubs of small lithographic area (0.075 mu m(2)) has been studied. Measurements of the conductance G at 90 mK as a function of the top gate voltage, which changes the stub height, show well-defined, almost periodic oscillations in G. A theoretical analysis, involving estimation of the shape and size of the device under gate biases and computation of the transmission probabilities from numerical analysis of the Schrodinger equation, successfully explains the main features of the experimental observations. The observed minima in G can be attributed to reflection resonances of electron waves from the resonant states of the stub cavity. This work establishes the potential of electron stub tuners in microelectronics applications. (C) 1999 American Institute of Physics. [S0003-6951(99)00605-1]. C1 USAF, Wright Lab, WL MLDO, Wright Patterson AFB, OH 45433 USA. CE Saclay, Serv Phys Etat Condense, F-91191 Gif Sur Yvette, France. Inst Semicond Phys, UA-252650 Kiev, Ukraine. Univ Glasgow, Dept Phys, Glasgow G12 8QQ, Lanark, Scotland. Arizona State Univ, Dept Elect Engn, Tempe, AZ 85287 USA. RP Debray, P (reprint author), USAF, Wright Lab, WL MLDO, Wright Patterson AFB, OH 45433 USA. OI Akis, Richard/0000-0002-4366-1891 NR 17 TC 26 Z9 26 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 1 PY 1999 VL 74 IS 5 BP 768 EP 770 DI 10.1063/1.123305 PG 3 WC Physics, Applied SC Physics GA 163AG UT WOS:000078379600046 ER PT J AU Kang, W Gu, GX Sparks, A Banda, S AF Kang, W Gu, GX Sparks, A Banda, S TI Bifurcation test functions and surge control for axial flow compressors SO AUTOMATICA LA English DT Article DE compressor; control; rotating stall; surge; bifurcation stabilization; test functions AB Surge control is investigated in conjunction with rotating stall control for axial flow compressors using a bifurcation approach. Test functions are developed to determine the existence and stability of the Hopf bifurcation associated with surge for closed-loop systems under linear state feedback. A control design method is proposed for the synthesis of linear feedback laws that eliminate surge, coupled with rotating stall for any given compact parameter set. Comparisons are made with existing results. Stabilization results are demonstrated with numerical simulations. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. Louisiana State Univ, Dept Elect & Comp Engn, Baton Rouge, LA 70803 USA. Wright Lab, Flight Dynam Directorate, Wright Patterson AFB, OH 45433 USA. RP Kang, W (reprint author), USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. NR 14 TC 8 Z9 9 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0005-1098 J9 AUTOMATICA JI Automatica PD FEB PY 1999 VL 35 IS 2 BP 229 EP 239 DI 10.1016/S0005-1098(98)00148-4 PG 11 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 173UD UT WOS:000078997400004 ER PT J AU Castillo, CY Lyons, TJ AF Castillo, CY Lyons, TJ TI The transoceanic air evacuation of unstable angina patients SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE air evacuation; ejection fraction; cardiac catheterization; angioplasty; coronary artery bypass graft surgery; unstable angina; Pacific theater; fixed winged aircraft; intermediate coronary syndrome ID ACUTE MYOCARDIAL-INFARCTION; FORCE AEROMEDICAL EVACUATION; TRANSPORT; EUROPE AB Background: The United States Air Force (USAF) air evacuation system in the Western Pacific frequently transports unstable angina patients on fixed wing aircraft over long distances to reach definitive cardiologic and cardiothoracic capabilities. This study begins to answer the question: Does the transfer of unstable angina (i.e., crescendo angina or rest angina) patients over long distances adversely affect the overall outcome of such patients? Methods: A case series study was conducted by obtaining a list of urgent and priority unstable angina patients from the Pacific theater from January 1992 through December 1996. Each of these patients' inpatient records were reviewed for cardiac catheterization (cath) result, ejection fraction (EF), previous cardiac history, angioplasty (PTCA) procedures, coronary artery bypass graft (CABG) surgery, and whether a patient had congestive heart failure (CHF), myocardial infarction (MI), death or other complications on this admission. Results: Of the 59 records reviewed, 61% (36/59) had coronary artery disease (CAD) of at least one vessel greater than 90% occlusion, 31% (18/59) had PTCA, 24% (14/59) had a CABG, 5% (3/59) had CHF, 3% (2/59) had an MI, 24% had some type of a complication, and 1.7% (7) died on this admission. Conclusion: Patients with significant CAD seem to tolerate air transport well with relatively few complications considering the overall morbidity and mortality associated with the diagnosis of unstable angina. C1 USAF, Sch Aerosp Med, Brooks AFB, TX 78235 USA. RP Castillo, CY (reprint author), USAF, Sch Aerosp Med, RAM 98,64 2602 W Gate Rd,Brooks 64, Brooks AFB, TX 78235 USA. NR 11 TC 7 Z9 7 U1 0 U2 2 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD FEB PY 1999 VL 70 IS 2 BP 103 EP 106 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 162DA UT WOS:000078329100001 PM 10206927 ER PT J AU Steeves, PE AF Steeves, PE TI Cervical pain in aviators - Reply SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Letter C1 USAF, Washington, DC 20330 USA. RP Steeves, PE (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD FEB PY 1999 VL 70 IS 2 BP 193 EP 194 PG 2 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 162DA UT WOS:000078329100020 ER PT J AU Carr-Lopez, S Exstrum, T Morse, T Shepherd, M Bush, AC AF Carr-Lopez, S Exstrum, T Morse, T Shepherd, M Bush, AC TI Efficacy of three statins at lower maintenance doses SO CLINICAL THERAPEUTICS LA English DT Article DE cholesterol; hydroxymethylglutaryl coenzyme A-reductase inhibitor; efficacy; comparative study ID CHOLESTEROL AB The purpose of this study was to determine whether patients who are receiving lovastatin 20 mg daily can be switched to daily regimens of lovastatin 10 mg, pravastatin 10 mg, or simvastatin 5 mg without loss of lipid control or an increase in side effects. One hundred five patients were identified whose lipid levels were clinically stable on a regimen of lovastatin 20 mg/d; these patients were randomly allocated to a group that continued to receive lovastatin 20 mg/d (the control group) or a group receiving 1 of the 3 alternative regimens. Patients were evaluated after 6 and 12 weeks of treatment for side effects and changes in liver and muscle enzymes and lipid levels compared with baseline. Of the 105 patients enrolled, 5 withdrew because of side effects, 4 did not return for follow up, and 3 were excluded. Ninety-three patients completed the 12-week study. When baseline values were compared to those at week 12 for each group, the proportions of patients meeting treatment goals for LDL cholesterol, as defined by the National Cholesterol Education Program, were as follows: control group, 30.8% improved; lovastatin 10 mg, 16.7% worsened; pravastatin 10 mg, 27.3% improved; and simvastatin 5 mg, no change. Patients who were switched from lovastatin 20 mg daily to pravastatin 10 mg or simvastatin 5 mg daily did not experience statistically significant changes in mean total cholesterol levels. Patients who were switched from 20 to 10 mg/d of lovastatin experienced increases in mean total cholesterol levels (from 195 mg/dL +/- 5 mg/dL at baseline to 200 mg/dL +/- 5 mg/dL at 12 weeks; P < 0.05). There were no differences in side effects or in elevations in liver or muscle enzymes. Thus patients who are stable on 20 mg/d lovastatin can be switched to a regimen of 10 mg/d pravastatin or 5 mg/d simvastatin. C1 Univ Pacific, Sch Pharm & Hlth Sci, Stockton, CA 95211 USA. RP Carr-Lopez, S (reprint author), SGQP, Med Grp 60, 101 Bodin Circle, Travis AFB, CA 94535 USA. NR 11 TC 3 Z9 3 U1 2 U2 2 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0149-2918 J9 CLIN THER JI Clin. Ther. PD FEB PY 1999 VL 21 IS 2 BP 331 EP 339 DI 10.1016/S0149-2918(00)88290-9 PG 9 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 182LT UT WOS:000079501000006 PM 10211536 ER PT J AU Elston, DM Stockwell, S AF Elston, DM Stockwell, S TI What's eating you? Triatome reduviids SO CUTIS LA English DT Editorial Material C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Elston, DM (reprint author), MMID, Dermatol Serv, Med Wing 59, 2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 3 TC 3 Z9 3 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD FEB PY 1999 VL 63 IS 2 BP 63 EP 64 PG 2 WC Dermatology SC Dermatology GA 167PP UT WOS:000078642700003 PM 10071730 ER PT J AU Russ, BW English, JC King, DHC Halbach, DP AF Russ, BW English, JC King, DHC Halbach, DP TI Amyopathic dermatomyositis associated with transitional cell carcinoma of the bladder SO CUTIS LA English DT Article ID SINE MYOSITIS; MALIGNANCY; CANCER AB Transitional cell carcinoma of the bladder is the most common tumor of the urinary tract. However, it has only been reported twice in the literature to be associated with the paraneoplastic syndrome dermatomyositis. We report a case of amyopathic dermatomyositis in a patient whose painless gross hematuria was due to transitional cell carcinoma of the bladder as well as review this association. C1 USAF, Peterson AFB, CO USA. Evans Army Community Hosp, Dermatol Serv, Ft Carson, CO USA. Evans Army Community Hosp, Urol Serv, Ft Carson, CO USA. Evans Army Community Hosp, Pathol Serv, Ft Carson, CO USA. RP English, JC (reprint author), 7500 Cochrane Circle, Ft Carson, CO 80913 USA. NR 17 TC 11 Z9 11 U1 0 U2 1 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD FEB PY 1999 VL 63 IS 2 BP 73 EP 76 PG 4 WC Dermatology SC Dermatology GA 167PP UT WOS:000078642700006 PM 10071733 ER PT J AU Wood, TS Shelley, ML AF Wood, TS Shelley, ML TI A dynamic model of bioavailability of metals in constructed wetland sediments SO ECOLOGICAL ENGINEERING LA English DT Article DE system dynamics; metal; constructed wetland; sediment; bioavailability; bioturbation ID ACID-VOLATILE SULFIDE; FRESH-WATER SEDIMENTS; CONTAMINATED SEDIMENTS; TOXICITY; CADMIUM; REMOVAL; OXIDATION; NICKEL; RIVER AB Constructed wetlands used for stormwater treatment accumulate metals primarily in their sediment. This sediment has the potential to produce toxic effects in benthic or aquatic organisms. Bioavailability of metals in sediments is directly linked to pore water metal activity. The mechanisms that influence pore water metal activity include physical, chemical, and biological processes. A system dynamics model was developed to represent these processes and the major influences affecting pore water metal activity in a treatment wetland receiving stormwater influent. The model structure and behavior were tested and validated using several system dynamics validation techniques. The model was run using metal specific parameter values typical of metals commonly found in stormwater runoff. Simulation results demonstrate that chemical processes of acid volatile sulfide (AVS) and organic carbon in binding metal in reduced sediments are the greatest influences in controlling metal bioavailability. The effect of bioturbation, as represented in the model, was negligible. The amount of organic carbon in the sediment plays the biggest role in controlling metal bioavailability in the long fun. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USAF, Inst Technol, Grad Sch Engn, AFIT ENV, Wright Patterson AFB, OH 45433 USA. RP Shelley, ML (reprint author), USAF, Inst Technol, Grad Sch Engn, AFIT ENV, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 44 TC 37 Z9 37 U1 0 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-8574 J9 ECOL ENG JI Ecol. Eng. PD FEB PY 1999 VL 12 IS 3-4 BP 231 EP 252 DI 10.1016/S0925-8574(98)00069-X PG 22 WC Ecology; Engineering, Environmental; Environmental Sciences SC Environmental Sciences & Ecology; Engineering GA 183AL UT WOS:000079530800004 ER PT J AU Brennan, MA Shelley, ML AF Brennan, MA Shelley, ML TI A model of the uptake, translocation, and accumulation of lead (Pb) by maize for the purpose of phytoextraction SO ECOLOGICAL ENGINEERING LA English DT Article DE phytoextraction; phytoremediation; lead (Pb); maize; uptake; translocation; precipitation ID CORN PLANTS; PHYTOREMEDIATION; CADMIUM; GROWTH; METALS AB Phytoextraction is a remediation technology that uses plants to remove heavy metals from soil. Effective implementation requires an understanding of plant processes that control uptake and translocation of metals from the soil. These processes are poorly understood. The purpose of this work is to gain insights on the plant mechanisms that control uptake and translocation of lead (Pb) from the soil and how these mechanisms interact to control levels of Pb accumulation in the plant. A mechanistic system dynamics modeling approach was used, simulating extraction and translocation of Pb by a maize plant. Confidence in the model structure was achieved through application of classical system dynamics validation procedures, Results of model simulations suggest that precipitation of Pb as a Pb-phosphate is one of the most important mechanisms in this system. Maximum saturable uptake rate of Pb and effective root mass may also be key plant parameters. The model may also be used to test phytoextraction management scenarios, two of which were tested in this study. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USAF, Inst Technol, Grad Sch Engn, AFIT ENV, Wright Patterson AFB, OH 45433 USA. RP Shelley, ML (reprint author), USAF, Inst Technol, Grad Sch Engn, AFIT ENV, 2950 P St, Wright Patterson AFB, OH 45433 USA. EM mshelley@afit.af.mil NR 57 TC 60 Z9 70 U1 0 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-8574 J9 ECOL ENG JI Ecol. Eng. PD FEB PY 1999 VL 12 IS 3-4 BP 271 EP 297 DI 10.1016/S0925-8574(98)00073-1 PG 27 WC Ecology; Engineering, Environmental; Environmental Sciences SC Environmental Sciences & Ecology; Engineering GA 183AL UT WOS:000079530800006 ER PT J AU McMackin, L Hugo, RJ Bishop, KP Chen, EY Pierson, RE Truman, CR AF McMackin, L Hugo, RJ Bishop, KP Chen, EY Pierson, RE Truman, CR TI High speed optical tomography system for quantitative measurement and visualization of dynamic features in a round jet SO EXPERIMENTS IN FLUIDS LA English DT Article ID FLOW VISUALIZATION; AXISYMMETRICAL JET; RECONSTRUCTION; REGION AB An optical tomography system that is capable of operating at frame rates of up to 5 kHz has been used to obtain spatially resolved cross-sectional temperature images of a heated round jet. These tomographic images show dynamic details in the evolving vortical flow structures found in the near field of the jet that are consistent with previous studies of low speed jet flow. Reconstructions produced by the system are quantitative temperature distributions of a planar cross section of the jet measuring temperature differences with a spatial resolution of 1.4 mm. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. Appl Technol Associates, Albuquerque, NM 87106 USA. Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. RP McMackin, L (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 27 TC 10 Z9 11 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD FEB PY 1999 VL 26 IS 3 BP 249 EP 256 DI 10.1007/s003480050286 PG 8 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 169EN UT WOS:000078734700010 ER PT J AU Baldwin, TL Schutz, SM Owens, G Olivier, K Little, C Abbott, R AF Baldwin, TL Schutz, SM Owens, G Olivier, K Little, C Abbott, R TI Successful endoscopic therapy of cholangitis associated with intrahepatic cholangiectasis in adult cystic fibrosis SO GASTROINTESTINAL ENDOSCOPY LA English DT Article ID LIVER-DISEASE C1 Wilford Hall USAF Med Ctr, Dept Gastroenterol, MMIG, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Pulmonol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Pediat, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. RP Baldwin, TL (reprint author), Wilford Hall USAF Med Ctr, Dept Gastroenterol, MMIG, 2200 Bergquist Dr, Lackland AFB, TX 78236 USA. NR 11 TC 2 Z9 2 U1 0 U2 2 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD FEB PY 1999 VL 49 IS 2 BP 249 EP 251 DI 10.1016/S0016-5107(99)70496-7 PG 3 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 165RK UT WOS:000078535000019 PM 9925708 ER PT J AU Toussaint, JA Martinsek, DM AF Toussaint, JA Martinsek, DM TI Integrated precision SAR targeting: A SAR targeting simulation SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB Operational deficiencies exist in the current ability to perform high resolution synthetic aperture radar (SAR) targeting for precision strike missions in difficult electronic countermeasure (ECM) and anti-aircraft environments. Increasingly sophisticated enemy defenses require that fire control information be derived from highly maneuverable aircraft trajectories rather than traditional straight-and-level flight. In addition, target area aspect information is needed to determine optimal attack approaches. These imaging and targeting conditions impose severe performance requirements on the sensor aircraft motion compensation system (MCS), and dictate the need for sophisticated algorithms to counteract ECM threats. This paper describes the development of a user friendly "Design Tool" for modeling and analysis of airborne radar system performance for SAR imaging and Precision SAR Targeting. C1 USAF, Res Lab, Targeting & Attack Radar Branch, Wright Patterson AFB, OH 45433 USA. RP Toussaint, JA (reprint author), USAF, Res Lab, Targeting & Attack Radar Branch, 2241 Avion Circle,Bldg 620, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD FEB PY 1999 VL 14 IS 2 BP 29 EP 32 DI 10.1109/62.746737 PG 4 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 164UD UT WOS:000078481200009 ER PT J AU McGahan, RV Kleinman, RE AF McGahan, RV Kleinman, RE TI The third annual special session on image reconstruction using real data, Part 1 SO IEEE ANTENNAS AND PROPAGATION MAGAZINE LA English DT Article DE electromagnetic scattering inverse problems; electromagnetic imaging; image reconstruction C1 USAF, Res Lab, Sensors Directorate, Bedford, MA 01731 USA. Univ Delaware, Ctr Math Waves, Dept Math Sci, Newark, DE 19716 USA. RP McGahan, RV (reprint author), USAF, Res Lab, Sensors Directorate, 31 Grenier St, Bedford, MA 01731 USA. NR 2 TC 23 Z9 23 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9243 J9 IEEE ANTENNAS PROPAG JI IEEE Antennas Propag. Mag. PD FEB PY 1999 VL 41 IS 1 BP 34 EP 36 DI 10.1109/MAP.1999.755022 PG 3 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 181HG UT WOS:000079435100005 ER PT J AU Marr, RA Pommet, DA Lammers, UHW McGahan, RV Fiddy, MA AF Marr, RA Pommet, DA Lammers, UHW McGahan, RV Fiddy, MA TI Target recognition from limited-angle backscatter data SO IEEE ANTENNAS AND PROPAGATION MAGAZINE LA English DT Article DE electromagnetic scattering inverse problems; electromagnetic imaging; image reconstruction ID IMAGES C1 USAF, Res Lab, Bedford, MA 01731 USA. Univ Massachusetts, Dept Elect & Comp Engn, Lowell, MA 01854 USA. RP Marr, RA (reprint author), USAF, Res Lab, 31 Grenier St, Bedford, MA 01731 USA. NR 10 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9243 J9 IEEE ANTENNAS PROPAG JI IEEE Antennas Propag. Mag. PD FEB PY 1999 VL 41 IS 1 BP 36 EP 40 DI 10.1109/74.755023 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 181HG UT WOS:000079435100006 ER PT J AU Pommet, DA Morris, JB McGahan, RV Fiddy, MA AF Pommet, DA Morris, JB McGahan, RV Fiddy, MA TI Imaging of unknown targets from measured scattering data SO IEEE ANTENNAS AND PROPAGATION MAGAZINE LA English DT Article DE electromagnetic scattering inverse problems; electromagnetic imaging; image reconstruction C1 Univ Massachusetts, Dept Elect & Comp Engn, Lowell, MA 01854 USA. USAF, Res Lab, Bedford, MA 01731 USA. RP Pommet, DA (reprint author), Univ Massachusetts, Dept Elect & Comp Engn, Lowell, MA 01854 USA. NR 15 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9243 J9 IEEE ANTENNAS PROPAG JI IEEE Antennas Propag. Mag. PD FEB PY 1999 VL 41 IS 1 BP 40 EP 44 DI 10.1109/74.755024 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 181HG UT WOS:000079435100007 ER PT J AU Taylor, CD Gutierrez, SJ Langdon, SL Murphy, KL AF Taylor, CD Gutierrez, SJ Langdon, SL Murphy, KL TI On the propagation of RF into a building constructed of cinder block over the frequency range 200 MHz to 3 GHz SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Article DE building materials; cinder block construction; fiber optics; network analyzer; radiowave propagation; swept frequencies ID WIRELESS AB A study of the RF propagation into a building having cinder-block Hall construction is performed by illuminating a two-story structure and recording the levels of the penetrant held over the frequency range 200 MHz to 3 GHz. Internal measurements are acquired at four points on the first Boor of the building. Since the building had no windows, the penetration into the building interior occurred primarily as a result of propagation through the Halls, The measured internal magnetic field of the illuminated building exhibited a 13-22 dB attenuation for the most part over the frequency range of the study. Multiple reflections from the ground, Halls, Boor, ceiling, etc, produce notable maxima and minima in the attenuation data as Hell as several deep nulls in the swept frequency responses. C1 USAF, Res Lab, PL, DEPE, Kirtland AFB, NM 87117 USA. RP Taylor, CD (reprint author), USAF, Res Lab, PL, DEPE, Kirtland AFB, NM 87117 USA. NR 10 TC 4 Z9 4 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD FEB PY 1999 VL 41 IS 1 BP 46 EP 49 DI 10.1109/15.748136 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 169VV UT WOS:000078770500007 ER PT J AU Peterkin, RE Roderick, NF Colella, S Lileikis, DE AF Peterkin, RE Roderick, NF Colella, S Lileikis, DE TI Three-dimensional hydromagnetic simulation of a high-velocity gas-puff Z-pinch SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE hydromagnetic Rayleigh-Taylor instability; three-dimensional MHD simulation; Z-pinch AB Experiments on the Sandia National Laboratories Saturn pulsed power machine have produced high-velocity Z-pinch plasma implosions of krypton gas puffs from a circular nozzle, We use the three-dimensional (3-D), time-dependent MACH3 magnetohydrodynamics code to simulate these experiments. Generally, the quality of Z-pinch implosions is degraded by hydromagnetic Rayleigh-Taylor instabilities, The images displayed in this paper illustrate the growth in time of this instability in three spatial dimensions from a modest (and realistic) initial 3-D perturbation. C1 USAF, Res Lab, Directed Energy Directorate, Ctr Plasma Theory & Computat, Kirtland AFB, NM 87117 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. NumerEx, Albuquerque, NM 87106 USA. RP Peterkin, RE (reprint author), USAF, Res Lab, Directed Energy Directorate, Ctr Plasma Theory & Computat, Kirtland AFB, NM 87117 USA. NR 5 TC 1 Z9 1 U1 2 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD FEB PY 1999 VL 27 IS 1 BP 118 EP 119 DI 10.1109/27.763078 PG 2 WC Physics, Fluids & Plasmas SC Physics GA 197MX UT WOS:000080369700058 ER PT J AU Jaynes, RL Gilgenbach, RM Hochman, JM Eidietis, N Rintamaki, JI Cohen, WE Peters, CW Lau, YY Spencer, TA AF Jaynes, RL Gilgenbach, RM Hochman, JM Eidietis, N Rintamaki, JI Cohen, WE Peters, CW Lau, YY Spencer, TA TI Velocity ratio measurement diagnostics and simulations of a relativistic electron beam in an axis encircling gyrotron SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE electron beams; electron optics; gyrotrons; microwave generation AB This paper reports on diagnostic experiments and simulations of a large-orbit, axis-encircling gyrotron, The electron's perpendicular to parallel velocity ratio alpha is measured. The experimental diagnostic consists of an apertured portion of the beam which is passed through a cusped magnetic field then collected on a glass plate. The cross section of the beam is recorded on the glass plate in a radiation darkened pattern. From the gyro-radius, B-field, and beam energy, alpha can be calculated. Particle distributions of the radiation darkened plate are in excellent agreement with numerical simulations of single particle orbits derived from the relativistic equations of motion. The experimental measurement of alpha yields values from 0.9 to 1.4, The simulations predict an alpha of 1.0 to 1.5. C1 Univ Michigan, Dept Nucl Engn & Radiol Sci, Intense Energy Beam Interact Lab, Ann Arbor, MI 48109 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Jaynes, RL (reprint author), Univ Michigan, Dept Nucl Engn & Radiol Sci, Intense Energy Beam Interact Lab, Ann Arbor, MI 48109 USA. NR 3 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD FEB PY 1999 VL 27 IS 1 BP 136 EP 137 DI 10.1109/27.763091 PG 2 WC Physics, Fluids & Plasmas SC Physics GA 197MX UT WOS:000080369700067 ER PT J AU Chen, CLP Wan, JZ AF Chen, CLP Wan, JZ TI A rapid learning and dynamic stepwise updating algorithm for flat neural networks and the application to time-series prediction SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART B-CYBERNETICS LA English DT Article ID FUNCTIONAL-LINK NET; FUNCTION APPROXIMATION; BACKPROPAGATION AB A fast learning algorithm is proposed to find an optimal weights of the flat neural networks (especially, the functional-link network). Although the hat networks are used for nonlinear function approximation, they can be formulated as linear systems. Thus, the weights of the networks can be solved easily using a linear least-square method. This formulation makes it easier to update the weights instantly for both a new added pattern and a new added enhancement node. A dynamic stepwise updating algorithm is proposed to update the weights of the system on-the-fly. The model is tested on several time-series data including an infrared laser data set, a chaotic time-series, a monthly flour price data set, and a nonlinear system identification problem. The simulation results are compared to existing models in which more complex architectures and more costly training are needed. The results indicate that the proposed model is very attractive to real-time processes. C1 Wright State Univ, Dept Comp Sci & Engn, Dayton, OH 45435 USA. USAF, Wright Lab, Mat Directorate, MLIM, Wright Patterson AFB, OH 45433 USA. Lexis Nexis Data Cent, Dayton, OH 45343 USA. RP Chen, CLP (reprint author), Wright State Univ, Dept Comp Sci & Engn, Dayton, OH 45435 USA. EM pchen@cs.wright.edu RI Chen, C. L. Philip/O-2657-2016 OI Chen, C. L. Philip/0000-0001-5451-7230 NR 28 TC 36 Z9 37 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1083-4419 J9 IEEE T SYST MAN CY B JI IEEE Trans. Syst. Man Cybern. Part B-Cybern. PD FEB PY 1999 VL 29 IS 1 BP 62 EP 72 DI 10.1109/3477.740166 PG 11 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Cybernetics SC Automation & Control Systems; Computer Science GA 158AQ UT WOS:000078094200006 PM 18252280 ER PT J AU Sanders, BP Mall, S Jackson, SC AF Sanders, BP Mall, S Jackson, SC TI Load ratio effects on fatigue response of titanium matrix composite at elevated temperature SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Article DE titanium matrix composites; fatigue; elevated temperature; load ratio effects ID BEHAVIOR; MODE AB Fatigue tests were conducted to characterize the effects of loading ratio (i.e. stress and strain ratios) on the fatigue life and damage mechanisms of a unidirectional, ceramic fiber reinforced titanium matrix composite (SCS-6/Ti-15-3) at elevated temperature (427 degrees C). Trends in the stress-strain response, fatigue life, and damage mechanisms were examined in detail for each control mode and loading ratio. A micromechanical analysis was also conducted to supplement the experimental observations. For the strain-controlled mode, it was observed that the most severe damage and shortest fatigue life occurred under the fully reversible condition when compared on the maximum strain basis. The fatigue life curves showed a layered effect (i.e. slopes were the same but they were shifted along the abscissa) when plotted on the maximum strain basis, with the fatigue life increasing as the strain ratio increased (i.e. as strain range decreased). Similar trends in damage and fatigue life were observed under the load-controlled mode. The fatigue life data from both loading modes collapsed on to a single curve when compared on the strain range basis for an applied loading ratio less than or equal to zero. However, at a loading ratio of 0.5, the fatigue life curves of the two loading modes diverged from each other as the strain range increased. In this case, the fatigue life under the strain-controlled mode was longer than under the load-controlled mode. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. EM small@afit.af.mil NR 27 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD FEB PY 1999 VL 21 IS 2 BP 121 EP 134 DI 10.1016/S0142-1123(98)00059-0 PG 14 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 161KX UT WOS:000078288800002 ER PT J AU Emery, BA Lathuillere, C Richards, PG Roble, RG Buonsanto, MJ Knipp, DJ Wilkinson, P Sipler, DP Niciejewski, R AF Emery, BA Lathuillere, C Richards, PG Roble, RG Buonsanto, MJ Knipp, DJ Wilkinson, P Sipler, DP Niciejewski, R TI Time dependent thermospheric neutral response to the 2-11 November 1993 storm period SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article ID GENERAL-CIRCULATION MODEL; IONOSPHERIC ELECTRODYNAMICS; GEOMAGNETIC STORMS; WINDS; TEMPERATURE; SATELLITE; CONDUCTIVITY; ATMOSPHERE; HEIGHT; WAVES AB Many satellite and ground-based observations from 2-11 November 1993 were combined in the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure to derive realistic time dependent global distributions of the auroral precipitation and ionospheric convection. These were then used as inputs to the Thermosphere-Ionosphere-Electrodynamics General Circulation Model(TIEGCM) to simulate the thermospheric and ionospheric response during the storm period. The November 1993 storm was an unusually strong storm associated with a recurring high speed stream of solar plasma velocity in the declining phase of the solar cycle. Significant gravity waves with phase speeds of about 700 m/s caused by Joule heating were present in the upper thermosphere as perturbations to the neutral temperature and wind fields, especially on 4 November. The observed gravity waves in the meridional wind and in the height of the electron density peak at several southern hemisphere stations were generally reproduced by the model using the AMIE high latitude inputs. Both model and observed equatorward winds were enhanced during the peak of the storm at Millstone Hill and at Australian ionosonde stations. The observed neutral temperature at Millstone Hill increased about 400 K during the night on 4 November, returning to normal on 9 November, while the model increased 300 K the first night at that location but was still elevated on 11 November. Enhanced westward winds during the storm were evident in the UARS WIND Imaging Interferometer (WINDII) data. The enhanced westward winds in the model were largest around 40-45 degrees magnetic latitude at night, and also tended to be largest in the longitudes containing the magnetic poles. The peak westward wind enhancements at 0 LT reached about 250 mi's at 300 km, and about 100 m/s at 125 km the first day of the storm at 40 degrees magnetic latitude. At 20 degrees magnetic latitude, the maximum westward wind enhancements at 125 km at 0 LT appeared 2-4 days after the major part of the storm, indicating very long time constants in the lower thermosphere. The model showed global average neutral temperature enhancements of 188 K after the peak of the storm that decayed with time, and which correlated with variations 8 h earlier in the Dst index and in the electric potential drop input from AMIE. The global average temperature enhancement of 188 K corresponded to a potential drop increase of only about 105 kV. The results showed that the TIEGCM using realistic AMIE auroral forcings were able to reproduce many of the observed time dependent features of this long-lived geomagnetic storm. The overall global average exospheric temperature variation correlated well with the time variation of the cross-tail potential drop and the Dst index during the storm period. However, the enhanced westward winds at mid-latitudes were strongly related to the corrected Joule heating defined by the time dependent AMIE inputs. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. CEPHAG, St Martin Dheres, France. Univ Alabama, Huntsville, AL 35899 USA. MIT, Haystack Observ, Westford, MA 01886 USA. USAF Acad, Colorado Springs, CO 80840 USA. IPS Radio & Space Serv, Chatswood, NSW, Australia. Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA. RP Emery, BA (reprint author), Natl Ctr Atmospher Res, High Altitude Observ, Pob 3000, Boulder, CO 80307 USA. NR 41 TC 47 Z9 47 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD FEB PY 1999 VL 61 IS 3-4 BP 329 EP 350 DI 10.1016/S1364-6826(98)00137-0 PG 22 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 181UQ UT WOS:000079461200012 ER PT J AU Haigler, BE Johnson, GR Suen, WC Spain, JC AF Haigler, BE Johnson, GR Suen, WC Spain, JC TI Biochemical and genetic evidence for meta-ring cleavage of 2,4,5-trihydroxytoluene in Burkholderia sp strain DNT SO JOURNAL OF BACTERIOLOGY LA English DT Article ID CATECHOL 2,3-DIOXYGENASE-ENCODING GENE; PSEUDOMONAS-SP; NUCLEOTIDE-SEQUENCE; HYDROXYQUINOL 1,2-DIOXYGENASE; EVOLUTIONARY RELATIONSHIPS; 2,4,5-TRICHLOROPHENOXYACETIC ACID; 2,3-DIHYDROXYBIPHENYL DIOXYGENASE; NAPHTHALENE DIOXYGENASE; EXTRADIOL DIOXYGENASE; PHYLOGENETIC TREES AB 2,4,5-Trihydroxytoluene (THT) oxygenase from Burkholderia sp, strain DNT catalyzes the conversion of THT to an unstable ring fission product. Biochemical and genetic studies of THT oxygenase were undertaken to elucidate the mechanism of the ring fission reaction, The THT oxygenase gene (dntD) was previously localized to the 1.2-kb DNA insert subcloned in the recombinant plasmid designated pJS76 (W. C. Suen and J. C. Spain, J. Bacteriol. 175:1831-1837, 1993), Analysis of the deduced amino acid sequence of DntD revealed the presence of the highly conserved residues characteristic of the catechol 2,3-dioxygenase gene family I. The deduced amino acid sequence of DntD corresponded to a molecular mass of 35 kDa, The native molecular masses for the THT oxygenase estimated by using gel filtration chromatography and nondenaturing gel electrophoresis were 67.4 and 77.8 kDa, respectively, The results suggested that the native protein consists of two identical subunits, The colorless protein contained 2 mol of iron per mol of protein. Stimulation of activity in the presence of ferrous iron and ascorbate suggested a requirement for ferrous iron in the active site. The properties of the enzyme are similar to those of the catechol 2,3-dioxygenases (meta-cleavage dioxygenases). In addition to THT, the enzyme exhibited activity towards 1,2,4-benzenetriol, catechol, 3- and 4-methylcatechol, and 3- and 4-chlorocatechol, The chemical analysis of the THT ring cleavage product showed that the product was 2,4-dihydroxy-5-methyl-6-oxo-2,4-hexadienoic acid, consistent with extradiol ring fission of THT. C1 USAF, Res Lab, MLQR, Tyndall AFB, FL 32403 USA. RP Spain, JC (reprint author), USAF, Res Lab, MLQR, 139 Barnes Dr, Tyndall AFB, FL 32403 USA. EM jspain@ccmail.aleq.tyndall.af.mil NR 65 TC 23 Z9 25 U1 0 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD FEB PY 1999 VL 181 IS 3 BP 965 EP 972 PG 8 WC Microbiology SC Microbiology GA 163EQ UT WOS:000078390600034 PM 9922262 ER PT J AU Hoffner, J von Zahn, U McNeil, WJ Murad, E AF Hoffner, J von Zahn, U McNeil, WJ Murad, E TI The 1996 Leonid shower as studied with a potassium lidar: Observations and inferred meteoroid sizes SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID COSMIC DUST; TEMPERATURE; DENSITY AB We report on the observation and analysis of meteor trails that are detected by ground-based lidar tuned to the D-1 fine structure line of K. The lidar is located at Kuhlungsborn, Germany. The echo profiles are analyzed with a temporal resolution of about 1 s and altitude resolution of 200 m. Identification of meteor trails in the large archive of raw data is performed with help of an automated computer search code. During the peak of the Leonid meteor shower on the morning of November 17, 1996, we observed seven meteor trails between 0245 and 0445 UT. Their mean altitude was 89.0 km. The duration of observation of individual trails ranges from 3 s to similar to 30 min. We model the probability of observing a meteor trail by ground-based lidar as a function of both altitude distribution and duration of the trails. These distributions depend on the mass distribution, entry velocity, and entry angle of the meteoroids, on the altitude-dependent chemical and dynamical lifetimes of the released K atom, and on the absolute detection sensitivity of our lidar experiment. From the modeling, we derive the statistical likelihood of detection of trails from meteoroids of a particular size. These bracket quite well the observed trails. The model also gives estimates of the probable size of the meteoroids based on characteristics of individual trails. C1 Leibniz Inst Atmospher Phys, D-18225 Kuhlungsborn, Germany. Radex Inc, Bedford, MA 01731 USA. USAF, Res Lab, Spaze Hazard Branch, Bedford, MA 01731 USA. RP Hoffner, J (reprint author), Leibniz Inst Atmospher Phys, D-18225 Kuhlungsborn, Germany. NR 17 TC 28 Z9 32 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD FEB 1 PY 1999 VL 104 IS A2 BP 2633 EP 2643 DI 10.1029/1998JA900063 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 170TX UT WOS:000078823900029 ER PT J AU Martelli, MF Grayson, RL Zasler, ND AF Martelli, MF Grayson, RL Zasler, ND TI Posttraumatic headache: Neuropsychological and psychological effects and treatment implications SO JOURNAL OF HEAD TRAUMA REHABILITATION LA English DT Article DE chronic pain; head trauma; neuropsychological tests; posttraumatic headache; treatment ID CHRONIC PAIN; TEMPOROMANDIBULAR DISORDERS; STRESS-DISORDER; INJURY PATIENTS; CERVICAL-SPINE; ATTENTION; WHIPLASH; DEFICITS; MIGRAINE; TRAUMA AB Posttraumatic headache (PTHA) is a frequent occurrence following trauma to the head, brain, and/or neck. Estimates of persistence for 6 months are as high as 44%. Review of available studies examining the effect of headache on neuropsychological test findings reveals that chronic headache pain, and chronic pain generally, exerts a significant and negative effect that poses a challenge to differential diagnostic efforts in the evaluation of mild brain injury. Given that PTHA is the most common postconcussive symptom and most frequent type of posttraumatic pain associated with mild traumatic brain injury (TBI), it follows that resolution of the postconcussion syndrome, and successful posttraumatic adaptation, may frequently rely on success in coping with PTHA symptomatology. Viewing PTHA from a biopsychosocial perspective, a general outline is offered for improving both assessment and treatment of PTHA. In addition, the most promising psychology-based treatment interventions are reviewed. C1 Concuss Care Ctr Virginia, Glen Allen, VA 23060 USA. Virginia Commonwealth Univ, Med Coll Virginia, Dept Psychiat, Dept Psychiat, Richmond, VA 23298 USA. Malcolm Grow Med Ctr, Andrews AFB, MD USA. Tree Life, Glenn Allen, VA USA. RP Martelli, MF (reprint author), Concuss Care Ctr Virginia, 10120 W Broad St,Suites G& H, Glen Allen, VA 23060 USA. NR 72 TC 35 Z9 36 U1 0 U2 0 PU ASPEN PUBL INC PI FREDERICK PA 7201 MCKINNEY CIRCLE, FREDERICK, MD 21704 USA SN 0885-9701 J9 J HEAD TRAUMA REHAB JI J. Head Trauma Rehabil. PD FEB PY 1999 VL 14 IS 1 BP 49 EP 69 PG 21 WC Clinical Neurology; Rehabilitation SC Neurosciences & Neurology; Rehabilitation GA 165LT UT WOS:000078523100007 PM 9949246 ER PT J AU Klasing, KS Thomas, SK Yerkes, KL AF Klasing, KS Thomas, SK Yerkes, KL TI Prediction of the operating limits of revolving helically grooved heat pipes SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE analytical; flow; heat transfer; heat pipes; rotating C1 Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. USAF, Res Lab, PRPG, Wright Patterson AFB, OH 45433 USA. RP Klasing, KS (reprint author), Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD FEB PY 1999 VL 121 IS 1 BP 213 EP 217 DI 10.1115/1.2825948 PG 5 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 177TP UT WOS:000079227400034 ER PT J AU Ratto-Kim, S Sitz, KV Garner, RP Kim, JH Davis, C Aronson, N Ruiz, N Tencer, K Redfield, RR Birx, DL AF Ratto-Kim, S Sitz, KV Garner, RP Kim, JH Davis, C Aronson, N Ruiz, N Tencer, K Redfield, RR Birx, DL TI Repeated immunization with recombinant gp160 human immunodeficiency virus (HIV) envelope protein in early HIV-1 infection: Evaluation of the T cell proliferative response SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article; Proceedings Paper CT Keystone Symposia, AIDS Pathogenesis CY APR, 1997 CL KEYSTONE, COLORADO ID IMMUNE-RESPONSES; INDIVIDUALS; VACCINE; IMMUNOGENICITY; GLYCOPROTEIN; VOLUNTEERS; INVITRO; ANTIGEN; DEFECTS; AIDS AB This longitudinal study was designed to evaluate cellular immunity in early-stage, asymptomatic human immunodeficiency virus (HIV)-1-infected persons (CD4 cell count, >400/mm(3); median, 625/mm(3) who were immunized with either recombinant (r) gp160 or placebo every 2 months for 5 years. Proliferative responses were assessed against rgp160, rp24, and a panel of recall antigens and mitogens. Despite good reactivity to recall antigens, at baseline similar to 33% had proliferative responses to gp160, and similar to 42% showed p24 gag responses. There was no statistical difference between vaccine and placebo groups for antigens or mitogens. After 1 year, similar to 73% of the subjects in the vaccine arm had new or boosted responses to gp160, versus similar to 18% in the placebo arm. Statistical significance was maintained throughout the study. Recurrent vaccination with recombinant gp160 was proven to be persistently immunogenic, increasing significantly the ability of HIV-1-infected persons to mount new proliferative responses to the vaccine. C1 Walter Reed Army Inst Res, Div Retrovirol, Rockville, MD USA. Henry M Jackson Fdn, Rockville, MD 20850 USA. Natl Naval Med Ctr, Bethesda, MD USA. Univ Maryland, Inst Human Virol, Baltimore, MD USA. Walter Reed Army Med Ctr, Washington, DC 20307 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Ratto-Kim, S (reprint author), Henry M Jackson Fdn, 13 Taft Court Suite 200, Rockville, MD 20850 USA. NR 21 TC 25 Z9 25 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD FEB PY 1999 VL 179 IS 2 BP 337 EP 344 DI 10.1086/314587 PG 8 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 162QB UT WOS:000078357300006 PM 9878016 ER PT J AU Organ, RJ Bottomlay, S Skapek, SX AF Organ, RJ Bottomlay, S Skapek, SX TI Evidence for apoptosis in dystrophin deficient muscular dystrophy SO JOURNAL OF INVESTIGATIVE MEDICINE LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Dept Pediat, San Antonio, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Pathol, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 1081-5589 J9 J INVEST MED JI J. Invest. Med. PD FEB PY 1999 VL 47 IS 2 SU S BP 135A EP 135A PG 1 WC Medicine, General & Internal; Medicine, Research & Experimental SC General & Internal Medicine; Research & Experimental Medicine GA 158VG UT WOS:000078137600729 ER PT J AU DiGeronimo, RJ Welke, TM Segura-Jones, L Seidner, SR AF DiGeronimo, RJ Welke, TM Segura-Jones, L Seidner, SR TI Effects of postnatal dexamethasone and exogenous surfactant on surfactant protein B mobilization in preterm rabbits SO JOURNAL OF INVESTIGATIVE MEDICINE LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Dept Pediat, Lackland AFB, TX 78236 USA. Univ Texas, Hlth Sci Ctr, Dept Pediat, San Antonio, TX 78284 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 1081-5589 J9 J INVEST MED JI J. Invest. Med. PD FEB PY 1999 VL 47 IS 2 SU S BP 142A EP 142A PG 1 WC Medicine, General & Internal; Medicine, Research & Experimental SC General & Internal Medicine; Research & Experimental Medicine GA 158VG UT WOS:000078137600762 ER PT J AU Rockwell, BA Hammer, DX Hopkins, RA Payne, DJ Toth, CA Roach, WP Druessel, JJ Kennedy, PK Amnotte, RE Eilert, B Phillips, S Noojin, GD Stolarski, DJ Cain, C AF Rockwell, BA Hammer, DX Hopkins, RA Payne, DJ Toth, CA Roach, WP Druessel, JJ Kennedy, PK Amnotte, RE Eilert, B Phillips, S Noojin, GD Stolarski, DJ Cain, C TI Ultrashort laser pulse bioeffects and safety SO JOURNAL OF LASER APPLICATIONS LA English DT Article DE lasers; retinal damage; laser pulses; eye safety ID RETINAL DAMAGE AB Recent studies of retinal damage due to ultrashort laser pulses have shown that less energy is required for retinal damage for pulses shorter than 1 ns than that for longer pulses. It has also been shown that more energy is required for near-infrared (NIR) wavelengths than in the visible because the light focuses behind the retina, requiring more energy to produce a damaging fluence on the retina. We review the progress made in determining the trends in retinal damage from laser pulses of 1 ns to 100 fs in the visible and NIR wavelength regimes. We have determined the most likely damage mechanism(s) operative in this pulse width regime. (C) 1999 Laser Institute of America. C1 USAF, Armstrong Lab, OEOP, Brooks AFB, TX 78235 USA. Duke Univ, Ctr Eye, Durham, NC 27710 USA. USAF, Off Sci Res, NL, Bolling AFB, DC 20332 USA. USAF, Armstrong Lab, OEV, Brooks AFB, TX 78235 USA. TASC, San Antonio, TX 78228 USA. RP Rockwell, BA (reprint author), USAF, Armstrong Lab, OEOP, 8111 18th St, Brooks AFB, TX 78235 USA. RI toth, cynthia/F-5614-2011 NR 8 TC 18 Z9 19 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1042-346X J9 J LASER APPL JI J. Laser Appl. PD FEB PY 1999 VL 11 IS 1 BP 42 EP 44 PG 3 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA 163EJ UT WOS:000078389800008 PM 10346063 ER PT J AU Ricks, MR Vogel, PS Elston, DM Hivnor, C AF Ricks, MR Vogel, PS Elston, DM Hivnor, C TI Purpuric agave dermatitis SO JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY LA English DT Article ID AMERICANA AB Agave americana is a low growing, thick, long-leaved, subtropical plant used for medicinal, commercial, and ornamental purposes. The plant's sap contains calcium oxalate crystals, acrid oils, saponins, and other compounds. Despite these known irritants, Agave-induced irritant dermatitis has rarely been reported. Previous case reports have noted a papulovesicular eruption consistent with an irritant contact dermatitis. We report a case of Agave-induced purpura in an otherwise healthy patient. Histopathology was consistent with an evolving leukocytoclastic vasculitis. C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Ricks, MR (reprint author), Wilford Hall USAF Med Ctr, Lackland AFB, San Antonio, TX 78236 USA. NR 5 TC 13 Z9 15 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0190-9622 J9 J AM ACAD DERMATOL JI J. Am. Acad. Dermatol. PD FEB PY 1999 VL 40 IS 2 SU S BP 356 EP 358 DI 10.1016/S0190-9622(99)70485-8 PN 2 PG 3 WC Dermatology SC Dermatology GA 165ET UT WOS:000078507800020 PM 10025868 ER PT J AU An, K Ravichandran, KS Dutton, RE Semiatin, SL AF An, K Ravichandran, KS Dutton, RE Semiatin, SL TI Microstructure, texture, and thermal conductivity of single-layer and multilayer thermal barrier coatings of Y2O3-stabilized ZrO2 and Al2O3 made by physical vapor deposition SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT 99th Annual Meeting of the American-Ceramic-Society CY MAY 04-07, 1997 CL CINCINNATI, OHIO SP Amer Ceram Soc ID THIN-FILMS; DIFFUSIVITY MEASUREMENTS AB Thermal conductivity is one of the most important properties in the design of thermal barrier coatings (TBCs) for high-temperature gas-turbine blades. In the present study, the thermal conductivities of several TBCs were studied. Single-layer and multilayer coatings consisting of Al2O3 and ZrO2 partially stabilized with 8 wt% Y2O3 (8YSZ) were deposited on nickel-base superalloy substrates by electron-beam physical vapor deposition (EB-PVD), A columnar microstructure with (200) texture and [200] direction oriented nearly perpendicularly to the plane of the coating was observed in the single-layer 8YSZ coating. In multilayer coatings with alternating layers of Al2O3 and 8YSZ, the tendency to develop columnar structure, as web as the intensity of (200) texture, decreased as the number of layers increased. In both the single-layer and multilayer coatings, the 8YSZ layer consisted almost entirely of tetragonal (t) phase with a negligible amount of monoclinic (m) phase. This was in contrast to the microstructure of bulk 8YSZ (source material used for deposition), which contained a significant amount of m phase, in addition to t phase. Whereas bulk Al2O3 consisted of alpha-phase, only gamma-phase was found in the Al2O3 layers of coatings. The thermal conductivities of these coatings were measured by the laser flash method. The thermal conductivity data of single-layer a 8YSZ coating compared well with the data on bulk ZrO2 stabilized by 5.3 wt% Y2O3 reported in the literature, This was due to the similarity of microstructures between the two. The thermal conductivity data of multilayer coatings were well described by a series heat-transfer model calculation within the limits of experimental errors involved in the measurements. C1 Univ Utah, Dept Met Engn, Salt Lake City, UT 84112 USA. USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLLM, Wright Patterson AFB, OH 45433 USA. RP An, K (reprint author), Univ Utah, Dept Met Engn, Salt Lake City, UT 84112 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 29 TC 73 Z9 74 U1 7 U2 23 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD FEB PY 1999 VL 82 IS 2 BP 399 EP 406 PG 8 WC Materials Science, Ceramics SC Materials Science GA 167VH UT WOS:000078654100019 ER PT J AU Brodzik, AK Mooney, JM AF Brodzik, AK Mooney, JM TI Convex projections algorithm for restoration of limited-angle chromotomographic images SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID SINGULAR-VALUE DECOMPOSITION; EXTRAPOLATION; RESOLUTION; REDUCTION; TRANSFORM AB We present a new algorithm for image restoration in limited-angle chromotomography. The algorithm is a generalization of the technique considered previously by the authors, based on a hybrid of a direct method of inversion and the iterative method of projections onto convex sets. The generalization is achieved by introducing a new object domain constraint. This constraint takes advantage of hyperspectral data redundancy and is realized by truncating the singular-value decomposition of the spatial-chromatic image matrix. As previously, the transform domain constraint is defined in terms of nonzero singular values of the system transfer function matrix. The new algorithm delivers high image fidelity, converges rapidly, and is easy to implement. Results of experiments on real data are included. (C) 1999 Optical Society of America [S0740-3232(99)00802-9]. C1 Sci Software, Woburn, MA 01801 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Sci Software, Woburn, MA 01801 USA. EM brodzik@max.rl.plh.af.mil NR 36 TC 23 Z9 23 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1084-7529 EI 1520-8532 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD FEB PY 1999 VL 16 IS 2 BP 246 EP 257 DI 10.1364/JOSAA.16.000246 PG 12 WC Optics SC Optics GA 161AV UT WOS:000078266300005 ER PT J AU Wells, JK Hagino, RT Bargmann, KM Jackson, MR Valentine, RJ Kakish, HB Clagett, GP AF Wells, JK Hagino, RT Bargmann, KM Jackson, MR Valentine, RJ Kakish, HB Clagett, GP TI Venous morbidity after superficial femoral-popliteal vein harvest SO JOURNAL OF VASCULAR SURGERY LA English DT Article; Proceedings Paper CT 46th Scientific Meeting of the International-Society-for-Cardiovascular-Surgery CY JUN 07-08, 1998 CL SAN DIEGO, CALIFORNIA SP Int Soc Cardiovasc Surg, N Amer Chapter ID LOWER-EXTREMITY DEEP; ULCERATION; REFLUX; INSUFFICIENCY; DISEASE; RECONSTRUCTION; SYMPTOMS; BYPASS AB Purpose: The superficial femoral-popliteal vein (SFPV) is a reliable conduit for aortoiliac, infrainguinal, and venous reconstructions. In this prospective study, we characterized the anatomic and physiologic changes in SFPV harvest limbs and their relationship to the development of late venous complications. Methods: Since 1990, we have studied 61 patients after harvest of 86 SFPVs at 6-month intervals with clinical examinations, lower-extremity venous duplex, and venous function tests. The CEAP system was used as a means of categorizing clinical changes. Results: Mean (+/- SEM) follow-up was 37 +/- 3 months. Less than one third of harvest limbs had edema without skin changes (C-3). NO patient had major chronic venous changes (C-4 to C-6) or venous claudication. There were no significant differences in limb measurements between harvest and non-harvest limbs, except in a subgroup of patients with unilateral harvest in which there was a small but significant (P = .046) increase in harvest limb thigh and calf circumference, compared with the opposite non-harl esr limb. These clinical results were not affected by the presence or absence of ail intact greater saphenous vein (GSV). Large, direct collaterals (4 to 6 mm in diameter) between the popliteal vein stump and profunda femoris vein (PFV) were seen by means of duplex ultrasonography in 29 harvest limbs (34%). The remainder appeared to have smaller, less direct collaterals to the PFV. Mild venous reflux with rapid cuff deflation was present at the popliteal or posterior tibial vein in nine of 79 harvest limbs (11%). Six of these nine limbs (67%) with reflux were clinical class C-3, compared with only 19 of the 70 limbs without reflux (27%; P = .02). Ambulatory venous pressure (AVP) with exercise was significantly increased in harvest limbs (60 +/- 4.7 mm Hg), compared with non-harvest limbs (47.8 +/- 5.2 mm Hg; P = .049). The AVP recovery time of harvest limbs (14.0 +/- 1.0 seconds) was reduced, compared with non-harvest limbs (23.5 +/- 4.5 seconds; P = .02). AVPs (exercise) remained stable or decreased in six of 10 harvest limbs measured serially. Venous refill time in harvest limbs (15.1 +/- 1.1 seconds) was shortened, compared with non-harvest limbs (22.3 +/- 2.1 seconds)(P = .002). Venous outflow obstruction measured by means of plethysmography was present in 93%;, of harvest limbs, compared with 36% of non-harvest limbs (P = .001). Conclusion: SFPV harvest results in minimal mid-term to late-term lower-extremity venous morbidity despite outflow obstruction. The most likely mechanisms preserving clinical status include the low incidence of mild reflux, the presence of collateral venous channels, and the lack of progression in abnormal harvest limb physiology. The absence of the ipsilateral GSV does not adversely affect clinical outcome. C1 Univ Texas, SW Med Ctr, Div Vasc Surg, Dallas, TX 75235 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. RP Clagett, GP (reprint author), Univ Texas, SW Med Ctr, Div Vasc Surg, 5323 Harry Hines Blvd, Dallas, TX 75235 USA. RI chen, xuanlan/H-4158-2011 NR 26 TC 65 Z9 67 U1 1 U2 2 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0741-5214 J9 J VASC SURG JI J. Vasc. Surg. PD FEB PY 1999 VL 29 IS 2 BP 282 EP 289 DI 10.1016/S0741-5214(99)70381-2 PG 8 WC Surgery; Peripheral Vascular Disease SC Surgery; Cardiovascular System & Cardiology GA 165QB UT WOS:000078528900016 PM 9950986 ER PT J AU Larsen, JM Shaw, LL Schadler, LS Liaw, PK AF Larsen, JM Shaw, LL Schadler, LS Liaw, PK TI Symposium on Fatigue and Creep of Composite Materials - Foreword SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Editorial Material C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLLN, Wright Patterson AFB, OH 45433 USA. Univ Connecticut, Dept Mat Sci & Engn, Storrs, CT 06269 USA. Rensselaer Polytech Inst, Dept Mat Sci & Engn, Troy, NY 12180 USA. Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. RP Larsen, JM (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLLN, Bldg 655,2230 10th St Suite, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 1999 VL 30 IS 2 BP 253 EP 253 PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 162FX UT WOS:000078336200001 ER PT J AU Maruyama, B Warrier, SG AF Maruyama, B Warrier, SG TI Fatigue crack growth in Ti-matrix composites with spatially varied interfaces SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Fatigue and Creep of Composite Materials, at the TMS/ASM Materials Week CY SEP 14-18, 1997 CL INDIANAPOLIS, INDIANA SP Minerals Met & Mat Soc, Composite Mat Comm, ASM Int ID FIBROUS COMPOSITES; BRIDGED CRACKS; DEFLECTION; SINGLE AB Spatially varied interfaces (SVIs) is a design concept for composite materials where the interface mechanical properties are varied along the length and circumference of the fiber/matrix interface. These engineered interfaces can be used to modify critical titanium matrix composite properties such as transverse tensile strength and fatigue crack growth resistance in ways that produce a balanced set of properties. The SVI approach may also be used to probe interface failure mechanisms for the purpose of understanding complex mechanical phenomena. Single lamina Ti-6Al-4V matrix composites containing strongly bonded SiC fibers were fabricated both in the as-received condition and with a weak longitudinal stripe along the sides of the fibers. The striped SVI composites exhibited an increase in the overall fatigue crack growth life of the specimens compared to the unmodified specimens. This improvement was caused by an increased extent of debonding and crack bridging in SVI composites. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45387 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. United Technol Res Ctr, E Hartford, CT 06108 USA. RP Maruyama, B (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45387 USA. RI Maruyama, Benji/E-3634-2010 NR 24 TC 1 Z9 1 U1 2 U2 8 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 1999 VL 30 IS 2 BP 267 EP 275 DI 10.1007/s11661-999-0315-2 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 162FX UT WOS:000078336200003 ER PT J AU Harmon, D Larsen, JM Peralta, A Hall, JA AF Harmon, D Larsen, JM Peralta, A Hall, JA TI Evaluation of the MMCLIFE 3.0 code in predicting crack growth in titanium aluminide composites SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Fatigue and Creep of Composite Materials, at the TMS/ASM Materials Week CY SEP 14-18, 1997 CL INDIANAPOLIS, INDIANA SP Minerals Met & Mat Soc, Composite Mat Comm, ASM Int ID BRIDGED CRACKS; FIBROUS COMPOSITES; FIBER COMPOSITES; FATIGUE AB Crack growth and fatigue life predictions made with the MMCLIFE 3.0 code are compared to test data for unidirectional, continuously reinforced SCS-6/Ti-14Al-21Nb (wt pet) composite laminates. The MMCLIFE 3.0 analysis package is a design tool capable of predicting strength and fatigue performance in metal matrix composite (MMC) laminates. The code uses a combination of micromechanic lamina and macromechanic laminate analyses to predict stresses and uses linear elastic fracture mechanics to predict crack growth. The crack growth analysis includes a fiber bridging model to predict the growth of matrix flaws in 0-deg laminates and is capable of predicting the effects of interfacial shear stress and thermal residual stresses. The code has also been modified to include edge-notch flaws in addition to center-notch flaws. The model was correlated with constant amplitude, isothermal data from crack growth tests conducted on 0- and 90-deg SCS-6/Ti-14-21 laminates. Spectrum fatigue tests were conducted, which included dwell times and frequency effects. Strengths and areas for improvement for the analysis are discussed. C1 Pratt & Whitney, E Hartford, CT 06108 USA. Boeing Co, St Louis, MO 63166 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Allied Signal Engines, Phoenix, AZ 85072 USA. Arizona State Univ, Tempe, AZ 85287 USA. Ormet Wah Chang, Albany, OR 97321 USA. RP Harmon, D (reprint author), Pratt & Whitney, E Hartford, CT 06108 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 1999 VL 30 IS 2 BP 287 EP 299 DI 10.1007/s11661-999-0317-0 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 162FX UT WOS:000078336200005 ER PT J AU Miracle, DB Majumdar, BS AF Miracle, DB Majumdar, BS TI Transverse creep of SiC/Ti-6Al-4V fiber-reinforced metal matrix composites SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Fatigue and Creep of Composite Materials, at the TMS/ASM Materials Week CY SEP 14-18, 1997 CL INDIANAPOLIS, INDIANA SP Minerals Met & Mat Soc, Composite Mat Comm, ASM Int ID SCS-6/TI-6AL-4V COMPOSITE; FAILURE AB The transverse creep response of an 8-ply SiC (SCS-6)/Ti-6Al-4V composite was measured at 482 degrees C from 69 to 276 MPa. Creep samples with fibers exposed at the edges as well as specimens with fully embedded fibers were tested under stepped loading conditions with increasing load. The response of each sample geometry was compared with creep data from the unreinforced matrix ('neat' material). The samples with exposed fiber ends exhibited minimum creep rates that were higher than those of the neat material at all stresses, and the stress exponent was slightly larger than the neat material. The embedded fiber samples possessed minimum creep rates that were smaller than the neat material at low stresses (<115 MPa), but became equivalent to the exposed fiber data at the highest stress (276 MPa). The apparent stress exponent for the embedded fiber composite was significantly larger than the neat material. The exposed fiber test data were well represented by a standard Crossman analysis, where the fibers were considered to have completely debonded. A stress singularity in the interfacial region at the sample edge is responsible for this behavior. The Crossman model was modified to incorporate the effect of a finite interface strength (120 MPa), and this was used to describe the response of the samples with embedded fibers. A reasonable fit to this representation was obtained. However, the measured minimum creep rate at the lowest stress was significantly lower than that predicted by the Crossman analysis for fully bonded fibers. C1 AF Res Lab, Mat & Mfg Directorate, Dayton, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Miracle, DB (reprint author), AF Res Lab, Mat & Mfg Directorate, Dayton, OH 45433 USA. NR 30 TC 12 Z9 12 U1 2 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 1999 VL 30 IS 2 BP 301 EP 306 DI 10.1007/s11661-999-0318-z PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 162FX UT WOS:000078336200006 ER PT J AU Calcaterra, JR Mall, S Coghlan, SC AF Calcaterra, JR Mall, S Coghlan, SC TI Degradation of residual strength in SCS-6/Ti-15-3 due to fully reversed fatigue SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Fatigue and Creep of Composite Materials, at the TMS/ASM Materials Week CY SEP 14-18, 1997 CL INDIANAPOLIS, INDIANA SP Minerals Met & Mat Soc, Composite Mat Comm, ASM Int ID TITANIUM-MATRIX COMPOSITE; BEHAVIOR AB Little attention has been given to residual strength degradation in titanium matrix composites (TMCs) after exposure to fatigue loading. To address this problem, fatigue tests on SCS-6/Ti-15-3 were performed to investigate the fatigue life and residual strength behavior of TMCs with different fiber volume fractions. Results indicate that fiber volume fraction seems to have an effect on both of these quantities. Lower fiber percentages result in a material where the characteristics of the matrix, such as hardening or cracking, play a much larger role in the composite response. Fatigue lives were not affected by fiber volume fraction at higher strain ranges, but lower fiber volume fractions resulted in shorter fatigue lives at lower strain values. Also, a slight increase in residual strength occurred up to 75 pet of fatigue life, for the lower-fiber volume fraction material. Despite these distinctions between specimens with different fiber contents, all specimens tested retained the majority of their strength prior to failure. C1 VAUS, AFRL, Wright Patterson AFB, OH 45433 USA. ENY, AFIT, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. Selectech Serv, Wright Patterson AFB, OH 45433 USA. RP Calcaterra, JR (reprint author), VAUS, AFRL, Wright Patterson AFB, OH 45433 USA. NR 19 TC 6 Z9 6 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 1999 VL 30 IS 2 BP 307 EP 313 DI 10.1007/s11661-999-0319-y PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 162FX UT WOS:000078336200007 ER PT J AU Shoales, GA German, RM AF Shoales, GA German, RM TI Combined effects of time and temperature on strength evolution using integral work-of-sintering concepts SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID POWDER COMPACTS; MICROSTRUCTURE AB Sintered materials have significantly higher strength than green compacts. The evolution of that strength during the sintering cycle involves a combination of annealing, thermal softening, and sintering events. The dynamic interplay between heating rate, sintering time, and sintering temperature controls the in situ strength and determines the final sintered strength. Although sintered strength is a well-explored subject, the dynamic evolution of strength requires new models. This research has measured both the sintered and in situ strengths as functions of heating rate, hold times, and temperature for die-compacted prealloyed bronze powder. A core concept is the use of an integral work of sintering to determine the effective strengthening due to sintering. The model is used to map strength evolution vs the key processing parameters. It is concluded that, during solid-state sintering of bronze, the key sources of distortion are the density and thermal gradients. C1 USAF Acad, Div Mat, Dept Engn Mech, Colorado Springs, CO 80840 USA. Penn State Univ, Dept Engn Sci & Mech, PM Lab, University Pk, PA 16802 USA. RP Shoales, GA (reprint author), USAF Acad, Div Mat, Dept Engn Mech, Colorado Springs, CO 80840 USA. OI German, Randall/0000-0002-5676-8532 NR 24 TC 10 Z9 10 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD FEB PY 1999 VL 30 IS 2 BP 465 EP 470 DI 10.1007/s11661-999-0336-x PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 162FX UT WOS:000078336200024 ER PT J AU Eaton, FD Nastrom, GD Hansen, AR AF Eaton, FD Nastrom, GD Hansen, AR TI Middle atmosphere slant-path optical turbulence conditions derived from very high frequency radar observations SO OPTICAL ENGINEERING LA English DT Article DE retractive index structure parameter; transverse coherence length; isoplanatic angle; Rytov variance; turbulence; radar; remote sensing; atmospheric propagation ID SANDS-MISSILE-RANGE; WHITE-SANDS; NEW-MEXICO; DESERT AB Slant path calculations are shown of the transverse coherence length (r(0)), the isoplanatic angle (theta(0)), and the Rytov variance (sigma(R)(2)), using a 6-yr data set of refractive index structure parameter (C-n(2)) from 49.25-MHz radar observations at White Sands Missile Range, New Mexico. The calculations are for a spherical wave condition; a wavelength (lambda) of electromagnetic radiation of 1 mu m; four different elevation angles (3, 10, 30, and 60 deg), two path lengths (50 and 150 km); and a platform, such as an aircraft, at 12.5 km MSL (mean sea level). Over 281,000 radar-derived C-n(2) profiles sampled at 3 min intervals with 150-m height resolution are used for the calculations. The approach, an "onion skin" model, assumes horizontal stationarity over each entire propagation path and is consistent with Taylor's hypothesis. The results show that refractivity turbulence effects are greatly reduced for the three propagation parameters (r(0), theta(0), and sigma(R)(2)) as the elevation angle increases from 3 to 60 deg. A pronounced seasonal effect is seen on the same parameters, which is consistent with climatological Variables and gravity wave activity. Interactions with the enhanced turbulence in the vicinity of the tropopause with the range weighting functions of each propagation parameter is evaluated. Results of a two region model relating r(0), theta(0), and sigma(R)(2) to wind speed at 5.6 km MSL are shown. This statistical model can be understood in terms of upward propagating gravity waves that are launched by strong winds over complex terrain. (C) 1999 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(99)01202-7]. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. St Cloud State Univ, St Cloud, MN 56301 USA. RP Eaton, FD (reprint author), USAF, Res Lab, 3550 Aberdeen SE, Kirtland AFB, NM 87117 USA. EM eatonf@plk.af.mil NR 26 TC 9 Z9 9 U1 0 U2 1 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD FEB PY 1999 VL 38 IS 2 BP 200 EP 207 DI 10.1117/1.602079 PG 8 WC Optics SC Optics GA 165DV UT WOS:000078505200001 ER PT J AU Peterson, P Gavrielides, A Sharma, MP AF Peterson, P Gavrielides, A Sharma, MP TI Modeling of high finesse, doubly resonant cw Raman lasers SO OPTICS COMMUNICATIONS LA English DT Article AB We model lasing in a high finesse, doubly resonant cw Raman laser. We derive expressions for threshold, power extraction, and the conditions for maximum Stokes output power. Our model confirms recent measurements [Brasseur et al., Optics Lett. 23 (1998) 367] of the Stokes output power as a function of the input pump power. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USAF, Res Labs, Nonlinear Opt Ctr Technol, DELO, Kirtland AFB, NM 87117 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. RP Peterson, P (reprint author), USAF, Res Labs, Nonlinear Opt Ctr Technol, DELO, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. EM peterson@harpo.plk.af.mil NR 7 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD FEB 1 PY 1999 VL 160 IS 1-3 BP 80 EP 85 DI 10.1016/S0030-4018(98)00631-2 PG 6 WC Optics SC Optics GA 165QM UT WOS:000078532500017 ER PT J AU Cooper, TM Natarajan, LV Miller, CG AF Cooper, TM Natarajan, LV Miller, CG TI Control by ring substitution of the conformation change dynamics in photochromic polypeptides SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID BACTERIORHODOPSIN FILMS; THIN-FILMS; POLY(SPIROPYRAN-L-GLUTAMATE); PHOTOMODULATION; HOLOGRAPHY AB In order to develop new systems that couple photochromism with molecular conformation change, a series of spiropyrans having different ring substituents were attached to poly(L-glutamic acid). The polypeptides were dissolved in hexafluoroisopropanol and dark adapted so that the dye was in the merocyanine form. Following adaptation by white light and dye photoconversion from the merocyanine to spiropyran forms, polypeptide dark-adaptation kinetics were monitored by circular dichroism (CD) and dye dark adaptation was monitored by UV/visible, Light adaptation caused a light-induced coil-to-helix transition, with dark adaptation resulting: in relaxation back to the coil. The dark-adaptation rate constant measured by UV/visible was equal to that measured by CD, demonstrating close coupling between dye state and polypeptide conformation. By varying the substituents on the spiropyran ring, dark-adaptation half lives were varied from less than a minute to 2 h, representing nearly three orders of magnitude. C1 USAF, Res Lab, MLPJ, Wright Patterson AFB, OH 45433 USA. Sci Applicat Int Corp, Dayton, OH USA. RP Cooper, TM (reprint author), USAF, Res Lab, MLPJ, 3005 P St Ste 1, Wright Patterson AFB, OH 45433 USA. NR 20 TC 1 Z9 1 U1 0 U2 1 PU AMER SOC PHOTOBIOLOGY PI AUGUSTA PA BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 USA SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD FEB PY 1999 VL 69 IS 2 BP 173 EP 176 PG 4 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 168VQ UT WOS:000078714200013 ER PT J AU Lemke, RW Genoni, TC Spencer, TA AF Lemke, RW Genoni, TC Spencer, TA TI Three-dimensional particle-in-cell simulation study of a relativistic magnetron SO PHYSICS OF PLASMAS LA English DT Article ID FLOW AB The A6 (six cavity) magnetron operated at relativistic voltages is investigated using three-dimensional particle-in-cell simulation. Previous experiments [A. Palevsky and G. Bekefi, Phys. Fluids 22, 986 (1979)] are repeated numerically for the purpose of ascertaining fidelity of code results in addition to obtaining insight into magnetron operation at high voltage. Simulations produce all qualitative behavior observed in experiments, with good quantitative agreement in most cases. This numerical study also reveals details concerning mode control, the cause and prevention of leakage current, and voltage scaling in the A6. It is shown that: (1) leakage current substantially reduces efficiency, (2) elimination of leakage current using cathode endcaps substantially increases efficiency, and (3) the functional dependence of operating voltage on applied magnetic field may depart from conventional scaling at very high voltage. (C) 1999 American Institute of Physics. [S1070-664X(99)01902-3]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Mission Res Corp, Albuquerque, NM 87106 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Lemke, RW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 53 Z9 56 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD FEB PY 1999 VL 6 IS 2 BP 603 EP 613 DI 10.1063/1.873205 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 159MF UT WOS:000078176800021 ER PT J AU Altrock, RC Rybansky, M Rusin, V Minarovjech, M AF Altrock, RC Rybansky, M Rusin, V Minarovjech, M TI Determination of the solar minimum period between cycles 22 and 23 from the coronal index of solar activity SO SOLAR PHYSICS LA English DT Article AB We present the coronal index of solar activity (CI) for 1997 and use the 1996 and 1997 data to examine the properties of the solar minimum between cycles 22 and 23. To compute CI, we used only the intensities of the green corona from Lomnicky Stit and Sacramento Peak coronal stations. Values of CI were low in the first half of 1997 with an increase from September toward the end of 1997. We determined the minimum in the green corona to be May 1996, which is in coincidence with the results from 2800 MHz radio flux, the Mg II index and the Wolf number. C1 USAF, Res Lab, Natl Solar Observ Sacramento Peak, Sunspot, NM 88349 USA. Slovak Acad Sci, Astron Inst, Tatranska Lomnic 05960, Slovakia. RP Altrock, RC (reprint author), USAF, Res Lab, Natl Solar Observ Sacramento Peak, POB 62, Sunspot, NM 88349 USA. NR 8 TC 11 Z9 11 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD FEB PY 1999 VL 184 IS 2 BP 317 EP 322 DI 10.1023/A:1005158132469 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 186QT UT WOS:000079741000008 ER PT J AU Copley, LAB Richards, BS Safavi, FZ Newton, PO AF Copley, LAB Richards, BS Safavi, FZ Newton, PO TI Hemodilution as a method to reduce transfusion requirements in adolescent spine fusion surgery SO SPINE LA English DT Article DE hemodilution; idiopathic scoliosis; intraoperative autologous transfusion; spinal fusion; transfusion ID ACUTE NORMOVOLEMIC HEMODILUTION; HYPOTENSIVE ANESTHESIA; HOMOLOGOUS TRANSFUSION; PREDEPOSITED BLOOD; AUTO-TRANSFUSION; AUTOLOGOUS BLOOD; SCOLIOSIS; EFFICACY AB Study Design. A case-control study. Objectives. 1) To determine if hemodilution adequately meets the transfusion needs in children who undergo posterior spinal fusion for idiopathic scoliosis and 2) to compare the efficacy of the various methods used to reduce the risk of allogeneic blood transfusion at the authors' institution. Summary of Background Data. Methods to reduce blood loss and avoid allogeneic blood transfusion caused by extensive spinal surgery in adolescents include 1) autologous blood predonation, 2) controlled hypotensive anesthesia, 3) intraoperative salvage of shed blood (cell saver), 4) acute normovolemic hemodilution, and 5) transfusion decisions by clinical judgment rather than by a preset value of hemoglobin. Although all methods have some efficacy, it is not clear which methods, separate or combined, are best in the adolescent scoliosis population. Methods. Hemodilution, hypotensive anesthesia, and cell saver were used in 43 children between June 1996 and July 1997. A comparison group (43 children) underwent went similar surgery with hypotensive anesthesia and cell saver, but no hemodilution (between July 1995 and December 1996). These two groups were similar with respect to means of age, levels of instrumentation, magnitude of curvature, estimated blood volume, mean arterial pressure; duration of surgery, duration of anesthesia, estimated blood loss, volume returned from cell saver, volume in the hemovac drain, and length of hospitalization. The groups differed in preoperative hemoglobin and hematocrit and in volume of crystalloid used. Results. Transfusions were given to 34 of 43 patients (79%) in the nonhemodilution group. These patients received 61 units of packed cells (57 autologous, 2 donor directed, and 2 allogeneic). In comparison, 16 of 43 patients (37%) in the hemodilution group required transfusion. They received 16 units of packed cells (15 autologous and 1 allogeneic). There was no significant difference between the groups with respect to postoperative hemoglobin and hematocrit immediately after surgery (hemodilution, 10.2/29.2; nonhemodilution, 10.0/29.1), postoperative day 1 (hemodilution, 9.2/26.9; nonhemodilution, 9.2/27.3), and postoperative day 2 (hemodilution 9.0/26.4; nonhemodilution, 9.2/27.1), There were no complications related to the technique of hemodilution in the 43 patients of this group. Cell saver was used in all patients, but sufficient volume to return blood to the patient was available in only 23 hemodilution patients (mean volume, 230 mL) and 25 nonhemodilution patients (mean volume, 215 mL). In only two patients of each group (<5%) did the volume returned prevent the absolute need for additional transfusions. Conclusions. Hemodilution was safely used as a method to satisfy the perioperative transfusion requirements of adolescents undergoing extensive spinal surgery. By allowing patients to arrive at surgery with a higher preoperative hemoglobin and hematocrit, and by decreasing the quantity of predonated autologous blood-collected and therefore used, the hemodiluton method may indirectly decrease the quantity of postoperative autologous transfusions in this populations. Cell saver was not shown to be effective, and its selective use is recommended. C1 USAF, Dept Orthopaed Surg, Med Operat Squadron 96, Eglin AFB, FL 32542 USA. Texas Scottish Rite Hosp Children, Dept Pediat Orthoped, Dallas, TX 75219 USA. Texas Scottish Rite Hosp Children, Dept Anesthesiol, Dallas, TX 75219 USA. Childrens Hosp, Dept Pediat Orthoped, San Diego, CA USA. RP Copley, LAB (reprint author), USAF, Dept Orthopaed Surg, Med Operat Squadron 96, Eglin AFB, FL 32542 USA. NR 20 TC 50 Z9 52 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0362-2436 J9 SPINE JI SPINE PD FEB 1 PY 1999 VL 24 IS 3 BP 219 EP 222 DI 10.1097/00007632-199902010-00005 PG 4 WC Clinical Neurology; Orthopedics SC Neurosciences & Neurology; Orthopedics GA 164NA UT WOS:000078469400004 PM 10025016 ER PT J AU Hedrick, A AF Hedrick, A TI Manual resistance training for football athletes at the US Air Force Academy SO STRENGTH AND CONDITIONING JOURNAL LA English DT Article DE free weights; football; manual resistance C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Hedrick, A (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU NATL STRENGTH & CONDITIONING ASSOC PI COLORADO SPRINGS PA 1955 N UNION BLVD, COLORADO SPRINGS, CO 80909 USA SN 1073-6840 J9 STRENGTH COND J JI Strength Cond. J. PD FEB PY 1999 VL 21 IS 1 BP 6 EP 10 PG 5 WC Sport Sciences SC Sport Sciences GA 170QC UT WOS:000078816700002 ER PT J AU Greenberg, MS Burton, GA Fisher, JW AF Greenberg, MS Burton, GA Fisher, JW TI Physiologically based pharmacokinetic modeling of inhaled trichloroethylene and its oxidative metabolites in B6C3F(1) mice SO TOXICOLOGY AND APPLIED PHARMACOLOGY LA English DT Article; Proceedings Paper CT 36th Annual Meeting of the Society-of-Toxicology CY MAR 09-13, 1997 CL CINCINNATI, OHIO SP Soc Toxicol DE PBPK; inhalation; trichloroethylene; trichloroethanol; trichloroacetic acid; dichloroacetic acid; chloral hydrate; mice ID MULTIROUTE EXPOSURE MODEL; TRICHLOROACETIC-ACID; DICHLOROACETIC ACID; SPECIES-DIFFERENCES; CHLORAL HYDRATE; CANCER RISK; MOUSE LUNG; RATS; HUMANS; CARCINOGENICITY AB A physiologically based pharmacokinetic (PBPK) model for inhaled trichloroethylene (TCE) was developed for B6C3F(1) mice. Submodels described four P450-mediated metabolites of TCE, which included chloral hydrate (CH), free and glucuronide-bound trichloroethanol (TCOH-f and TCOH-b), trichloroacetic acid (TCA), and dichloroacetic acid (DCA). Inhalation time course studies were carried out for calibration of the model by exposing mice to TCE vapor concentrations of either 100 or 600 ppm for 4 h. At several time points, mice were euthanized and blood, liver, kidney, lung, and fat were collected and analyzed for TCE and its oxidative metabolites. Peak blood TCE concentrations were 0.86 and 7.32 mu g/mL, respectively, in mice exposed to 100 and 600 ppm TCE. The model overpredicted the mixed venous blood and tissue concentrations of TCE for mice of both exposure groups. Fractional absorption of inhaled TCE was proposed to explain the discrepancy between the model predictions and the TCE blood time course data. When fractional absorption (53%) of inhaled TCE was incorporated into the model, a comprehensive description of the uptake, distribution, and clearance of TCE in the blood was obtained. Fractional uptake of inhaled TCE was further verified by collecting TCE in exhaled breath following a 4-h constant concentration exposure to TCE and validation was provided by testing the model against TCE blood concentrations from an independent data set. The submodels adequately simulated the distribution and clearance kinetics of CH and TCOH-f in blood and the lungs, TCOH-b in the blood, and TCA and DCA, which were respectively detected for up to 43 and 14 h postexposure in blood and livers of mice exposed to 600 ppm TCE. This is the first extensive tissue time course study of the major metabolites of TCE following an inhalation exposure to TCE and the PBPK model predictions were in good general agreement with the observed kinetics of the oxidative metabolites formed in mice exposed to TCE concentrations of 100 and 600 ppm. (C) 1999 Academic Press. C1 USAF, Operat Toxicol Branch AFRL HEST, Res Lab, Wright Patterson AFB, OH 45433 USA. Wright State Univ, Dept Biol Sci, Inst Environm Qual, Dayton, OH 45435 USA. RP Greenberg, MS (reprint author), USAF, Operat Toxicol Branch AFRL HEST, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 60 TC 24 Z9 24 U1 3 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0041-008X J9 TOXICOL APPL PHARM JI Toxicol. Appl. Pharmacol. PD FEB 1 PY 1999 VL 154 IS 3 BP 264 EP 278 DI 10.1006/taap.1998.8594 PG 15 WC Pharmacology & Pharmacy; Toxicology SC Pharmacology & Pharmacy; Toxicology GA 167GD UT WOS:000078623400008 PM 9931286 ER PT J AU Miceli, MP Rehg, M Near, JP Ryan, KC AF Miceli, MP Rehg, M Near, JP Ryan, KC TI Can laws protect whistle-blowers? Results of a naturally occurring field experiment SO WORK AND OCCUPATIONS LA English DT Article ID BEHAVIOR; ORGANIZATIONS; RETALIATION; GOVERNMENT; ATTITUDES AB Data collected over three time periods,from 1980 to 1992, show massive changes in the ways in which federal employees reported wrongdoing and the effects on them for having done so. Laws intended to encourage whistle-blowing seem to have two desired effects: to reduce the incidence of perceived wrongdoing and to increase the likelihood of whistle-blowing. However, two unintended effects are also observed: perceived retaliation increased and whistle-blowers increasingly sought anonymity. The basic model predicting retaliation is essentially the same in the three time periods in which data were collected Implications for research, practice, and the design of future legislation are discussed. C1 Georgetown Univ, McDonough Sch Business, Washington, DC 20057 USA. USAF, Inst Technol, Washington, DC 20330 USA. Indiana Univ, Bloomington, IN 47405 USA. RP Miceli, MP (reprint author), Georgetown Univ, McDonough Sch Business, Washington, DC 20057 USA. NR 50 TC 41 Z9 42 U1 1 U2 6 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0730-8884 J9 WORK OCCUPATION JI Work Occup. PD FEB PY 1999 VL 26 IS 1 BP 129 EP 151 DI 10.1177/0730888499026001007 PG 23 WC Industrial Relations & Labor; Sociology SC Business & Economics; Sociology GA 164GM UT WOS:000078454900006 ER PT J AU Warrier, SG Maruyama, B Gambone, ML Lin, RY AF Warrier, SG Maruyama, B Gambone, ML Lin, RY TI Special issue - Processing-Structure-Property Relationship of Composite Interfaces Symposium - Preface SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Editorial Material C1 Universal Energy Syst Inc, Dayton, OH 45432 USA. USAF, Mat & Mfg Directorate, RL, MLLM, Wright Patterson AFB, OH 45433 USA. Allison Engine Co, Indianapolis, IN 46206 USA. Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45220 USA. RP Warrier, SG (reprint author), United Technol Res Ctr, E Hartford, CT 06108 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 1999 VL 259 IS 2 BP VII EP VII PG 1 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 162ET UT WOS:000078333100001 ER PT J AU Majumdar, BS AF Majumdar, BS TI Development and characterization of new coatings for improved balance of mechanical properties of titanium matrix composites SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT TMS Symposium on Processing-Structure-Property Relationship of Composite Interfaces CY FEB 15-18, 1998 CL SAN ANTONIO, TX DE fiber-matrix coatings; SiC system; sheath; push-out; longitudinal; transverse ID FATIGUE-CRACK GROWTH; REINFORCED COMPOSITES; FIBER; INTERFACE; MICROSTRUCTURE; ALPHA-2 AB The need for improved transverse performance of titanium matrix composites (TMCs) has stimulated efforts at developing fiber-matrix coatings with a better blend of transverse and longitudinal properties. In the first part of this paper, the critical requirements for an appropriate coating are examined, based on experience gained from single-fiber and single-ply tests on TMCs. Two new coatings are then discussed: (i) the Ti-Y-Ti system, abbreviated as TYT; and (ii), the sheathed SiC system. The coatings were characterized under transverse loading using the cruciform specimen geometry, and under longitudinal tension using a single-ply dog-bone geometry. The transverse strength of the TYT system was approximate to 160 MPa, and needs further improvement. The fiber had poor in situ strength, and is explained based on less than expected performance of the Y layer due to oxygen pickup and columnar grain structure. The sheathed fiber offered a better blend of transverse and longitudinal properties. Under transverse loading, the sheath remained load bearing until an applied stress as high as 550 MPa, compared with only 330 MPa for SCS-B fibers. Under longitudinal tension, while the sheath cracked at relatively low stresses, the base SIC region appeared to retain a strength that was identical to a virgin carbon-coated Trimarc fiber. The sheathed fiber appears attractive for TMC laminates, and further experimental validation is suggested. (C) 1999 Elsevier Science S.A. All rights reserved. C1 USAF, Mat & Mfg Directorate, Res Labs, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Majumdar, BS (reprint author), USAF, Mat & Mfg Directorate, Res Labs, Wright Patterson AFB, OH 45433 USA. NR 37 TC 7 Z9 9 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 1999 VL 259 IS 2 BP 171 EP 188 DI 10.1016/S0921-5093(98)00903-4 PG 18 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 162ET UT WOS:000078333100004 ER PT J AU Warrier, SG Maruyama, B Majumdar, BS Miracle, DB AF Warrier, SG Maruyama, B Majumdar, BS Miracle, DB TI Behavior of several interfaces during fatigue crack growth in SiC/Ti-6Al-4V composites SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT TMS Symposium on Processing-Structure-Property Relationship of Composite Interfaces CY FEB 15-18, 1998 CL SAN ANTONIO, TX DE interfaces; titanium matrix composites; fatigue crack growth; bridging; elastic shielding ID TITANIUM MATRIX COMPOSITES; DEFLECTION AB The fatigue crack growth behavior of a large number of continuous fiber-reinforced titanium matrix composite systems with significantly different interfacial characteristics were examined in this study using single-ply specimens. Crack deflection, debonding, and bridging were observed in most composites, even for the ones with strongly bonded fibers. Experimental results supported a stress-based criterion for predicting the debonding behavior. Crack kinking and penetration as well as fiber strength degradation and in situ fiber strength issues have been addressed in the context of preserving the bridging characteristics. General trends in the crack growth response with variations in the interface bond strength have been observed, wherein the normalized bridging stress decreases gradually with an increase in the bond strength. This gradual decrease suggests the possibility of obtaining improved transverse properties without substantial degradation to the longitudinal fatigue crack growth properties. (C) 1999 Elsevier Science S.A. All rights reserved. C1 USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Miracle, DB (reprint author), USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RI Maruyama, Benji/E-3634-2010 NR 35 TC 16 Z9 21 U1 2 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 1999 VL 259 IS 2 BP 189 EP 200 DI 10.1016/S0921-5093(98)00891-0 PG 12 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 162ET UT WOS:000078333100005 ER PT J AU Warrier, SG Rangaswamy, P Bourke, MAM Krishnamurthy, S AF Warrier, SG Rangaswamy, P Bourke, MAM Krishnamurthy, S TI Assessment of the fiber/matrix interface bond strength in SiC/Ti-6Al-4V composites SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT TMS Symposium on Processing-Structure-Property Relationship of Composite Interfaces CY FEB 15-18, 1998 CL SAN ANTONIO, TX DE residual stress; transverse properties; neutron diffraction; interface bund strength; finite element analysis ID FIBER SCS-6/TI-6AL-4V COMPOSITE; TITANIUM MATRIX COMPOSITES; RESIDUAL-STRESSES; SIC-FIBER; SINGLE; DIFFRACTION; CERAMICS; STRAINS; FAILURE AB The mechanical properties of composites are significantly influenced by the properties of the fiber/matrix interface. From a fundamental as well as an interface development standpoint it is necessary to determine the bond strength of interface. The calculated value of the interface bond strength is extremely sensitive to the value of the compressive radial residual stress at the interface since this residual stress has to be overcome before interface separation can occur. In this study, neutron diffraction was employed to measure radial residual stresses in SCS-6/Ti-6Al-4V composites. A combination of stress measurements, finite element analyses and transverse tension tests was employed to systematically evaluate the interface bond strength. The fiber/matrix interface bond strength for SCS-6/Ti-6Al-4V composites was determined to be about 140 MPa. (C) 1999 Elsevier Science S.A. All rights reserved. C1 USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. RP Warrier, SG (reprint author), USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 35 TC 35 Z9 40 U1 3 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 1999 VL 259 IS 2 BP 220 EP 227 DI 10.1016/S0921-5093(98)00894-6 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 162ET UT WOS:000078333100008 ER PT J AU Pandey, AB Majumdar, BS Miracle, DB AF Pandey, AB Majumdar, BS Miracle, DB TI Effect of aluminum particles on the fracture toughness of a 7093/SiC/15p composite SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT TMS Symposium on Processing-Structure-Property Relationship of Composite Interfaces CY FEB 15-18, 1998 CL SAN ANTONIO, TEXAS DE discontinuously reinforced aluminum; fracture toughness; ductility; mechanisms; crack growth ID CRACK AB The effects of Al-particles on the toughness of a discontinuously reinforced aluminum (DRA) alloy composite were studied in this investigation. A powder metallurgically processed 'control' DRA consisting of 7093iSiC/15p (10 mu m) was selected as the base material. The remaining DRAs contained aluminum particles of different size, volume fraction and composition, that were blended with the base DRA, and powder metallurgically processed and extruded; they are termed as 'bean' materials. The modulus, yield strength, and work hardening rate of the bean materials with Al-alloy particles were quite insensitive to the distribution of the SiC particles. On the other hand, the strain to failure was most strongly influenced by the presence of pure-Al and Al-alloy particles, and is explained based on the local SiC particle volume fraction. Fracture toughness calculations show that the ASTM E-561 procedure is more appropriate for DRA materials, that exhibit small scale yielding conditions, than ASTM E-813 and E-1152 procedures. The bean materials exhibited improved crack growth toughnesses over the control DRA, and in some cases the initiation toughness was also increased. The toughening mechanisms are discussed. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Universal Energy Syst Inc, Dayton, OH 45432 USA. USAF, Mat & Mfg Directorate, Res Lab, MLLM, Wright Patterson AFB, OH 45433 USA. RP Pandey, AB (reprint author), Universal Energy Syst Inc, 4401 Dayton Xenia Rd, Dayton, OH 45432 USA. NR 23 TC 32 Z9 35 U1 7 U2 19 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 31 PY 1999 VL 259 IS 2 BP 296 EP 307 DI 10.1016/S0921-5093(98)00901-0 PG 12 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 162ET UT WOS:000078333100016 ER PT J AU Collins, CB Davanloo, F Iosif, MC Dussart, R Hicks, JM Karamian, SA Ur, CA Popescu, II Kirischuk, VI Carroll, JJ Roberts, HE McDaniel, P Crist, CE AF Collins, CB Davanloo, F Iosif, MC Dussart, R Hicks, JM Karamian, SA Ur, CA Popescu, II Kirischuk, VI Carroll, JJ Roberts, HE McDaniel, P Crist, CE TI Accelerated emission of gamma rays from the 31-yr isomer of Hf-178 induced by X-ray irradiation SO PHYSICAL REVIEW LETTERS LA English DT Article ID LASER AB A sample of 6.3 X 10(14) nuclei of the 4-quasiparticle isomer of Hf-178 having a half-life of 31 yr and excitation energy of 2.446 MeV was irradiated with x-ray pulses from a device typically used in dental medicine. It was operated at 15 mA to produce bremsstrahlung radiation with an end point energy set to be 70 or 90 keV. Spectra of the isomeric target were taken with a high purity Ge detector. Intensities of selected transitions in the normal decay cascade of the Hf-178 isomer were found to increase by about 4%. Such an accelerated decay is consistent with an integrated cross section of 1 x 10(-21) cm(2) keV for the resonant absorption of x rays to induce gamma decay. C1 Univ Texas, Ctr Quantum Elect, Richardson, TX 75083 USA. Joint Inst Nucl Res, Dubna 141980, Russia. H Hulubei Natl Inst Phys & Nucl Engn, Bucharest, Romania. RC IGE Fdn, Bucharest, Romania. Inst Nucl Res, Ctr Sci, Kiev, Ukraine. Youngstown State Univ, Ctr Photon Induced Proc, Youngstown, OH 44555 USA. SRS Technol, Syst Technol Grp, Huntsville, AL 35812 USA. USAF, Res Lab, DEPA, Albuquerque, NM 87117 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Univ Texas, Ctr Quantum Elect, Richardson, TX 75083 USA. NR 9 TC 113 Z9 120 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 25 PY 1999 VL 82 IS 4 BP 695 EP 698 DI 10.1103/PhysRevLett.82.695 PG 4 WC Physics, Multidisciplinary SC Physics GA 160DN UT WOS:000078215300006 ER PT J AU Herbelin, JM Henshaw, TL Rafferty, BD Anderson, BT Tate, RF Madden, TJ Manke, GC Hager, GD AF Herbelin, JM Henshaw, TL Rafferty, BD Anderson, BT Tate, RF Madden, TJ Manke, GC Hager, GD TI The measurement of gain on the 1.315 mu m transition of atomic iodine in a subsonic flow of chemically generated NCl(a(1)Delta) SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ENERGY-TRANSFER; LASER AB Gain is measured on the electronic I(P-2(3/2))-I*(P-2(1/2)) transition of atomic iodine at 1.315 mu m when hydrazoic acid HN3 is injected into a flow of iodine and chlorine atoms. The inversion was generated in a transverse subsonic flow device that produced electronically excited I*(P-2(1/2)) atoms from the efficient energy transfer reaction between NCl(a(1)Delta) metastable and ground state I(P-2(3/2)) atoms. The population inversion was directly observed using a 1.315 mu m tunable diode laser that scanned the entire line shape of the (3,4) hyperfine transition of iodine. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Henshaw, TL (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 19 TC 39 Z9 41 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD JAN 22 PY 1999 VL 299 IS 6 BP 583 EP 588 DI 10.1016/S0009-2614(98)01292-5 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 160AY UT WOS:000078209200010 ER PT J AU Marshall, P Misra, A Schwartz, M AF Marshall, P Misra, A Schwartz, M TI A computational study of the enthalpies of formation of halomethylidynes SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HALON THERMOCHEMISTRY; CONTAINING MOLECULES; EXTENSION; HEATS AB The halomethylidynes CH, CF, CCl, CBr, and CI have been investigated using GAUSSIAN-2 theory and calculations up to QCISD(T)/6-311+G(3df, 2p). At the latter level of theory bond lengths, harmonic frequencies, and anharmonicity corrections have been derived and compare well with experimental measurements where these are available. GAUSSIAN-2 and QCISD(T)/6-311+G(3df, 2p) energies were employed in isodesmic reactions to obtain the following recommended enthalpies of formation (Delta(f)H(298)) in kJ mol(-1):CF, 248.6; CCl, 436.9; CBr, 497.1; CI, 557.6. Estimated error limits are +/-6 kJ mol(-1). (C) 1999 American Institute of Physics. [S0021-9606(99)30804-7]. C1 N Texas State Univ, Dept Chem, Denton, TX 76203 USA. USAF, Ctr Computat Modeling Nonstruct Mat, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Marshall, P (reprint author), N Texas State Univ, Dept Chem, Denton, TX 76203 USA. NR 22 TC 9 Z9 10 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JAN 22 PY 1999 VL 110 IS 4 BP 2069 EP 2073 DI 10.1063/1.477870 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 156ZU UT WOS:000078034900026 ER PT J AU Hollkamp, JJ Bagley, RL Gordon, RW AF Hollkamp, JJ Bagley, RL Gordon, RW TI A centrifugal pendulum absorber for rotating, hollow engine blades SO JOURNAL OF SOUND AND VIBRATION LA English DT Letter C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Hollkamp, JJ (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 10 TC 9 Z9 11 U1 2 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD JAN 21 PY 1999 VL 219 IS 3 BP 539 EP 549 DI 10.1006/jsvi.1998.1964 PG 11 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 157EF UT WOS:000078046600009 ER PT J AU Dawson, DL Beebe, HG Davidson, MH Chinoy, DA Herd, JA Hiatt, WR Heckman, JD Bortey, EB Forbes, WP AF Dawson, DL Beebe, HG Davidson, MH Chinoy, DA Herd, JA Hiatt, WR Heckman, JD Bortey, EB Forbes, WP TI Cilostazol or pentoxifylline for claudication? (vol 98, pg 58, 1998) SO CIRCULATION LA English DT Correction C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Jobst Vasc Ctr, Toledo, OH USA. Chicago Ctr Clin Res, Chicago, IL USA. Jacksonville CV Ctr, Jacksonville, FL USA. Baylor Coll Med, Houston, TX 77030 USA. Univ Colorado, Denver, CO 80202 USA. Otsuka Amer Pharmaceut Inc, Rockville, MD 20852 USA. RP Dawson, DL (reprint author), Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD JAN 19 PY 1999 VL 99 IS 2 BP 328 EP 328 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 157YZ UT WOS:000078090400027 ER PT J AU Drummond, JP Clarson, SJ Zetts, JS Hopkins, FK Caracci, SJ AF Drummond, JP Clarson, SJ Zetts, JS Hopkins, FK Caracci, SJ TI Enhanced electro-optic poling in guest-host systems using conductive polymer-based cladding layers SO APPLIED PHYSICS LETTERS LA English DT Article ID MODULATORS AB We report on the development of conductive polymer-based cladding layers for use in multilayered electro-optic (EO) device structures. The waveguide claddings used in these studies were based on blends formed from the conductive polymer poly (ethylene dioxythiophene) with poly (vinylalcohol). Thin films of the blended materials were spun to form cladding layers having tunable conductivity and optical absorption. We tested these materials using a well-known guest-host core layer to determine their effect on the polar alignment of second order nonlinear optical chromophores. The claddings tested were shown to provide a large effective poling field across the active layer, and thus produced larger EO coefficients than systems having comparable, but more highly resistive, claddings. (C) 1999 American Institute of Physics. [S0003-6951(99)00103-5]. C1 Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45221 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Drummond, JP (reprint author), Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45221 USA. EM drummojs@email.uc.edu NR 13 TC 29 Z9 29 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 18 PY 1999 VL 74 IS 3 BP 368 EP 370 DI 10.1063/1.123073 PG 3 WC Physics, Applied SC Physics GA 158TW UT WOS:000078133800014 ER PT J AU Mills, JD Sheehy, JA Ferrett, TA Southworth, SH Mayer, R Lindle, DW Langhoff, PW AF Mills, JD Sheehy, JA Ferrett, TA Southworth, SH Mayer, R Lindle, DW Langhoff, PW TI Comment on "nondipole resonant X-ray Raman spectroscopy: Polarized inelastic scattering at the K edge of Cl-2" Reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 USAF, Res Lab, AFRL, PRS,Prop Sci Div, Edwards AFB, CA 93524 USA. Carleton Coll, Dept Chem, Northfield, MN 55057 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Johns Hopkins Hosp, Dept Radiat Oncol, Baltimore, MD 21205 USA. Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. RP Mills, JD (reprint author), USAF, Res Lab, AFRL, PRS,Prop Sci Div, Edwards AFB, CA 93524 USA. NR 5 TC 3 Z9 3 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JAN 18 PY 1999 VL 82 IS 3 BP 667 EP 667 DI 10.1103/PhysRevLett.82.667 PG 1 WC Physics, Multidisciplinary SC Physics GA 157KC UT WOS:000078059200054 ER PT J AU Unwin, C Blatchley, N Coker, W Ferry, S Hotopf, M Hull, L Ismail, K Palmer, I David, A Wessely, S AF Unwin, C Blatchley, N Coker, W Ferry, S Hotopf, M Hull, L Ismail, K Palmer, I David, A Wessely, S TI Health of UK servicemen who served in Persian Gulf War SO LANCET LA English DT Article ID POSTTRAUMATIC-STRESS-DISORDER; VIETNAM VETERANS HEALTH; SELF-REPORTED HEALTH; US VETERANS; EXPOSURE; POPULATION; PREVALENCE; COMBAT; RECALL; SCALE AB Background Various symptoms in military personnel in the Persian Gulf War 1990-91 have caused international speculation and concern. We investigated UK servicemen. Methods We did a cross-sectional postal survey on a random sample of Gulf War veterans (Gulf War cohort, n=4248) and, stratified for age and rank, servicemen deployed to the Bosnia conflict (Bosnia cohort, n=4250) and those serving during the Gulf War but not deployed there (Era cohort, n=4246). We asked about deployment, exposures, symptoms, and illnesses. We analysed men only. Our outcome measures were physical health, functional capacity (SF-36), the general health questionnaire, the Centers for Disease Control and Prevention (CDC) multisymptom criteria for Gulf war illness, and post-traumatic stress reactions. Findings There were 8195 (65.1%) valid responses. The Gulf War cohort reported symptoms and disorders significantly more frequently than those in the Bosnia and Era cohorts, which were similar. Perception of physical health and ability were significantly worse in the Gulf War cohort than in the other cohorts, even after adjustment for confounders. Gulf War veterans were more likely than the Bosnia cohort to have substantial fatigue (odds ratio 22 [95% CI 1.9-2.6]), symptoms of post-traumatic stress (2.6 [1.9-3.4]), and psychological distress (1.6 [1/.4-1.8]), and were nearly twice as likely to reach the CDC case definition (25 [2.2-2.8]). In the Gulf War, Bosnia, and Era cohorts, respectively, 61.9%, 36.8%, and 36.4% met the CDC criteria, which fell to 25.3%, 11.8%, and 12.2% for severe symptoms. Potentially harmful exposures were reported most frequently by the Gulf War cohort. All exposures showed associations with all of the outcome measures in the three cohorts. Exposures specific to the Gulf were associated with all outcomes. Vaccination against biological warfare and multiple routine vaccinations were associated with the CDC multisymptom syndrome in the Gulf War cohort. Interpretation Service in the Gulf War was associated with various health problems over and above those associated with deployment to an unfamiliar hostile environment. Since associations of ill health with adverse events and exposures were found in all cohorts, however, they may not be unique and causally implicated in Gulf-War-related illness. A specific mechanism may link vaccination against biological warfare agents and later ill health, but the risks of illness must be considered against the protection of servicemen. C1 Guys Kings & St Thomas Med Sch, Gulf War Illness Res Unit, London SE5 8AF, England. USAF, Med Operat Agcy, Washington, DC 20330 USA. Off Natl Stat, London, England. Royal Def Med Coll, London, England. RP Wessely, S (reprint author), Guys Kings & St Thomas Med Sch, Gulf War Illness Res Unit, London SE5 8AF, England. EM s.wessely@iop.bpmf.ac.uk RI Wessely, Simon/A-8713-2008; Hotopf, Matthew/E-4971-2010; David, Anthony/C-1315-2011 OI David, Anthony/0000-0003-0967-774X NR 35 TC 373 Z9 374 U1 2 U2 16 PU LANCET LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0140-6736 J9 LANCET JI Lancet PD JAN 16 PY 1999 VL 353 IS 9148 BP 169 EP 178 DI 10.1016/S0140-6736(98)11338-7 PG 10 WC Medicine, General & Internal SC General & Internal Medicine GA 159LW UT WOS:000078175600008 PM 9923871 ER PT J AU Greiner, DZ Personius, BE Andrews, TC AF Greiner, DZ Personius, BE Andrews, TC TI Effects of withdrawal of chronic estrogen therapy on brachial artery vasoreactivity in women with coronary artery disease SO AMERICAN JOURNAL OF CARDIOLOGY LA English DT Article ID POSTMENOPAUSAL WOMEN; VASODILATION; ACETYLCHOLINE; ESTRADIOL; RESPONSES; AUGMENTS AB Withdrawal of oral estrogen therapy is associated with a deterioration in endothelial function in post:menopausal women with coronary artery disease. Our data also suggest that withdrawal of estrogen results in enhanced hyperemic flow, although this observation will require validation with further study. C1 Univ Texas, SW Med Ctr, Dept Internal Med, Div Cardiol, Dallas, TX 75235 USA. Wilford Hall USAF Med Ctr, Div Cardiol, Lackland AFB, TX 78236 USA. RP Andrews, TC (reprint author), Univ Texas, SW Med Ctr, Dept Internal Med, Div Cardiol, 5323 Harry Hines Blvd, Dallas, TX 75235 USA. NR 15 TC 12 Z9 12 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0002-9149 J9 AM J CARDIOL JI Am. J. Cardiol. PD JAN 15 PY 1999 VL 83 IS 2 BP 247 EP + DI 10.1016/S0002-9149(98)00828-5 PG 4 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 158HC UT WOS:000078109100017 PM 10073827 ER PT J AU Nee, R Doppenschmidt, D Donovan, DJ Andrews, TC AF Nee, R Doppenschmidt, D Donovan, DJ Andrews, TC TI Intravenous versus subcutaneous vitamin K-1 in reversing excessive oral anticoagulation SO AMERICAN JOURNAL OF CARDIOLOGY LA English DT Article ID COMPLICATIONS AB Our data suggest that compared with the subcutaneous route of administration, intravenous vitamin K-1 results in a more prompt reduction in the international normalized ration. However, for most patients, subcutaneous vitamin K-1 is an effective and safe alternative when used in conjunction with modification of subsequent warfarin dosing, because virtually all patients achieved a safe level of anticoagulation within 72 hours with this route of administration. C1 Univ Texas, SW Med Ctr, Div Cardiol, Dallas, TX 75235 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Andrews, TC (reprint author), Univ Texas, SW Med Ctr, Div Cardiol, 5323 Harry Hines Blvd, Dallas, TX 75235 USA. NR 7 TC 41 Z9 43 U1 0 U2 1 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 USA SN 0002-9149 J9 AM J CARDIOL JI Am. J. Cardiol. PD JAN 15 PY 1999 VL 83 IS 2 BP 286 EP + DI 10.1016/S0002-9149(98)00842-X PG 5 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 158HC UT WOS:000078109100031 PM 10073841 ER PT J AU Adler, TR Leonard, JG Nordgren, RK AF Adler, TR Leonard, JG Nordgren, RK TI Improving risk management: moving from risk elimination to risk avoidance SO INFORMATION AND SOFTWARE TECHNOLOGY LA English DT Article DE risk avoidance; cleanroom development; life-cycle cost AB This study has examined software reliability using a risk management framework to analyze popular risk management models with regard to their emphasis on risk avoidance. Too often, risk reduction occurs late in the software development life cycle when changes are costly and less effective. We suggest that early risk avoidance techniques, like the cleanroom software development process and its sub-process of software inspections, leads to superior products. Our approach is different from the current mainstream approach of testing to eliminate errors because we propose using risk models that emphasize preventive risk management early in development. We argue that the use of risk avoidance leads to benefits that far outweigh the cost of implementation. Published by Elsevier Science B.V. C1 USAF, Inst Technol, Dept Grad Acquisit Management, Wright Patterson AFB, OH 45433 USA. RP Adler, TR (reprint author), USAF, Inst Technol, Dept Grad Acquisit Management, Wright Patterson AFB, OH 45433 USA. NR 27 TC 11 Z9 11 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0950-5849 J9 INFORM SOFTWARE TECH JI Inf. Softw. Technol. PD JAN 15 PY 1999 VL 41 IS 1 BP 29 EP 34 DI 10.1016/S0950-5849(98)00095-0 PG 6 WC Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA 169LH UT WOS:000078749300003 ER PT J AU Ham, BS Shahriar, MS Hemmer, PR AF Ham, BS Shahriar, MS Hemmer, PR TI Enhancement of four-wave mixing and line narrowing by use of quantum coherence in an optically dense double-Lambda solid SO OPTICS LETTERS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; HYPERFINE-STRUCTURE; PHASE CONJUGATION; CRYSTAL; SPECTROSCOPY; INTERFERENCE; SODIUM AB We have demonstrated enhanced nondegenerate four-wave mixing by use of a resonant, probe in a double-A system consisting of an optically dense spectral hole-burning solid. The observed probe diffraction efficiency is similar to 16% in amplitude at 6 K which is higher than for an off-resonant probe in a A-type scheme. We have also observed two-photon coherence line narrowing, which has potential application to high-resolution spectroscopy. (C) 1999 Optical Society of America. C1 USAF, Bedford, MA 01731 USA. RP Ham, BS (reprint author), USAF, Bedford, MA 01731 USA. RI Shahriar, Selim/B-7270-2009 NR 21 TC 25 Z9 27 U1 0 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD JAN 15 PY 1999 VL 24 IS 2 BP 86 EP 88 DI 10.1364/OL.24.000086 PG 3 WC Optics SC Optics GA 157WZ UT WOS:000078085800006 PM 18071416 ER PT J AU Joshi, MP Pudavar, HE Swiatkiewicz, J Prasad, PN Reianhardt, BA AF Joshi, MP Pudavar, HE Swiatkiewicz, J Prasad, PN Reianhardt, BA TI Three-dimensional optical circuitry using two-photon-assisted polymerization SO APPLIED PHYSICS LETTERS LA English DT Article ID WAVE-GUIDES; LASER; ABSORPTION; MEMORY; DYE AB An approach using an as-formed solid bulk sample containing a blend of photocurable and thermally curable epoxies together with a highly efficient two-photon excitable fluorophore is demonstrated for in situ fabrication of three-dimensional optical circuitry with a precise control of dimension and spatial locations. Confocal volume images of a 1 X 2 splitter and a grating coupler are shown. End-fire coupling of a He-Ne laser beam into the 1 X 2 splitter has been achieved. (C) 1999 American Institute of Physics. [S0003-6951(99)03602-5]. C1 SUNY Buffalo, Dept Chem, Photon Res Lab, Buffalo, NY 14260 USA. SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. USAF, Res Lab, Polymer Branch, WL MLBP Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Joshi, MP (reprint author), SUNY Buffalo, Dept Chem, Photon Res Lab, Buffalo, NY 14260 USA. EM pnprasad@acsu.buffalo.edu NR 20 TC 123 Z9 125 U1 6 U2 20 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 11 PY 1999 VL 74 IS 2 BP 170 EP 172 DI 10.1063/1.123283 PG 3 WC Physics, Applied SC Physics GA 155JC UT WOS:000077942400004 ER PT J AU Garter, M Scofield, J Birkhahn, R Steckl, AJ AF Garter, M Scofield, J Birkhahn, R Steckl, AJ TI Visible and infrared rare-earth-activated electroluminescence from indium tin oxide Schottky diodes to GaN : Er on Si SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; LIGHT-EMITTING-DIODES; IMPLANTED GAN; DOPED SILICON; ERBIUM; PHOTOLUMINESCENCE; LUMINESCENCE; EXCITATION; GREEN; BLUE AB Visible and infrared rare-earth-activated electroluminescence (EL) has been obtained from Schottky barrier diodes consisting of indium tin oxide (ITO) contacts on an Er-doped GaN layer grown on Si. The GaN was grown by molecular beam epitaxy on Si substrates using solid sources for Ga, Mg, and Er and a plasma source for N-2. RF-sputtered ITO was used for both diode electrodes. The EL spectrum shows two peaks at 537 and 558 nm along with several peaks clustered around 1550 nm. These emission lines correspond to atomic Er transitions to the I-4(15/2) ground level and have narrow linewidths. The optical power varies linearly with reverse bias current. The external quantum and power efficiencies of GaN:Er visible light-emitting diodes have been measured, with values of 0.026% and 0.001%, respectively. Significantly higher performance is expected from improvements in the growth process, device design, and packaging. (C) 1999 American Institute of Physics. [S0003-6951(99)01002-5]. C1 Univ Cincinnati, Nanoelect Lab, Cincinnati, OH 45221 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Garter, M (reprint author), Univ Cincinnati, Nanoelect Lab, Cincinnati, OH 45221 USA. OI Steckl, Andrew/0000-0002-1868-4442 NR 23 TC 84 Z9 84 U1 2 U2 22 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 11 PY 1999 VL 74 IS 2 BP 182 EP 184 DI 10.1063/1.123286 PG 3 WC Physics, Applied SC Physics GA 155JC UT WOS:000077942400008 ER PT J AU Goldstein, JT Ehrlich, G AF Goldstein, JT Ehrlich, G TI Site blocking in surface diffusion SO SURFACE SCIENCE LA English DT Article DE adatoms; atomistic dynamics; models of surface kinetics; single crystal surfaces; surface diffusion ID ADSORBATE-ADSORBATE INTERACTIONS; NEAREST-NEIGHBOR INTERACTIONS; SINGLE-CRYSTAL SURFACES; MONTE-CARLO; STEPPED SURFACES; COEFFICIENTS; NITROGEN; ATTRACTION; REPULSION AB Interactions between adatoms can change the diffusivity in a surface layer as the concentration is increased. Another effect that may contribute, however, is sire blocking: the probability that an atom can find a sire into which to jump diminishes as the concentration increases. The contribution of site blocking to the concentration dependence of the diffusivity is illustrated by considering two non-interacting lattice gases: a Langmuir layer, and a lattice gas with exclusion of nearest-neighbor sites. In both, site blocking is shown to compete with the thermodynamic factor in affecting the diffusivity. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. RP Goldstein, JT (reprint author), USAF, Wright Lab, MLPO, P St,Suite 6, Wright Patterson AFB, OH 45433 USA. NR 27 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JAN 11 PY 1999 VL 420 IS 1 BP 1 EP 5 DI 10.1016/S0039-6028(98)00635-9 PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 161QY UT WOS:000078301500003 ER PT J AU Butler, JT Bright, VM Cowan, WD AF Butler, JT Bright, VM Cowan, WD TI Average power control and positioning of polysilicon thermal actuators SO SENSORS AND ACTUATORS A-PHYSICAL LA English DT Article DE micro-electro-mechanical systems; modeling; thermal actuators ID CONDUCTIVITY; SILICON; ARRAYS AB This paper reports on characterizing and modeling the behavior of micromachined polysilicon thermal actuators when driven by DC or pulsed drive signals. Thermal actuators can be controlled and positioned using a pulsed input with a period much less than the thermal time constant of the device as demonstrated by data collected in air and vacuum. Both pulse width and pulse amplitude modulation were successfully employed to position lateral actuators, lateral actuator arrays, and piston micro-mirrors. A SPICE model for polysilicon thermal actuators was developed using relationships between resistance, deflection, and average power. This model incorporates the polysilicon thermal actuator's electrical load, transient response, and deflection characteristics necessary for predicting actuator performance and developing microsystems. The SPICE model exhibits very close agreement with the measured performance of the polysilicon thermal actuators. Published by Elsevier Science S.A. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. RP Butler, JT (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 15 TC 25 Z9 25 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-4247 J9 SENSOR ACTUAT A-PHYS JI Sens. Actuator A-Phys. PD JAN 8 PY 1999 VL 72 IS 1 BP 88 EP 97 DI 10.1016/S0924-4247(98)00211-8 PG 10 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 163BA UT WOS:000078381300010 ER PT B AU Browning, JM Henderson, D AF Browning, JM Henderson, D BE Olgren, C TI Synchronous, internet based training using BrightLight (TM) by USAF Chaplain Service SO 15TH ANNUAL CONFERENCE ON DISTANCE TEACHING AND LEARNING, PROCEEDINGS LA English DT Proceedings Paper CT 15th Annual Conference on Distance Teaching and Learning CY AUG 04-06, 1999 CL MADISON, WI C1 USAF, Chaplain Serv Inst, CPD, HC, Maxell AFB, AL 36112 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU UNIVERSITY WISCONSIN DISTANCE TEACHING & LEARNING CONFERENCE PI MADISON PA 1050 UNIV AVE, B-136 LATHROP H ALL, MADISON, WI 53706 USA PY 1999 BP 57 EP 63 PG 7 WC Education & Educational Research SC Education & Educational Research GA BR07M UT WOS:000165566600009 ER PT S AU Fugate, RQ AF Fugate, RQ GP SPIE SPIE TI Progress in atmospheric adaptive optics SO 18TH CONGRESS OF THE INTERNATIONAL COMMISSION FOR OPTICS: OPTICS FOR THE NEXT MILLENNIUM, TECHNICAL DIGEST SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 18th Congress of the International Commission for Optics - Optics for the Next Millennium CY AUG 02-06, 1999 CL SAN FRANCISCO, CA SP SPIE, Amer Physical Soc, IEEE Lasers & electro Optics Soc, OSA Optical Soc Amer, Int Comm Optics, US Advisory Comm Int Commiss Opt ID SYSTEM AB Significant advances have been made in the development and performance of large scale adaptive optical systems in recent years. Technological innovations in sensors, processors, wave front correctors, and laser guide stars have all contributed to the rapid growth of adaptive optics as an enabling technology for ground based optical astronomy in the 21(st) century. C1 USAF, Res Lab, Starfire Opt Range, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Fugate, RQ (reprint author), USAF, Res Lab, Starfire Opt Range, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 5 TC 1 Z9 1 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 0-8194-3234-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3749 BP 24 EP 25 DI 10.1117/12.354741 PG 2 WC Optics SC Optics GA BN74Q UT WOS:000082790200011 ER PT S AU Andersen, G Knize, RJ AF Andersen, G Knize, RJ GP SPIE SPIE TI Holographically corrected telescope for high bandwidth optical communications SO 18TH CONGRESS OF THE INTERNATIONAL COMMISSION FOR OPTICS: OPTICS FOR THE NEXT MILLENNIUM, TECHNICAL DIGEST SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 18th Congress of the International Commission for Optics - Optics for the Next Millennium CY AUG 02-06, 1999 CL SAN FRANCISCO, CA SP SPIE, Amer Physical Soc, IEEE Lasers & electro Optics Soc, OSA Optical Soc Amer, Int Comm Optics, US Advisory Comm Int Commiss Opt AB We describe a method by which a lightweight, lo Lv-quality, reflecting primary is holographically corrected to diffraction limited operation. The resulting telescope can be used to transmit or receive optical data signals with frequencies up to 100GHz with high SNR (>60dB). The simplicity of this design makes it ideal for future global satellite networks or space probe communications. C1 USAF Acad, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. RP Andersen, G (reprint author), USAF Acad, Laser & Opt Res Ctr, Suite 2A31,2354 Fairchild Dr, Colorado Springs, CO 80840 USA. NR 0 TC 1 Z9 1 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 0-8194-3234-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3749 BP 30 EP 31 DI 10.1117/12.354763 PG 2 WC Optics SC Optics GA BN74Q UT WOS:000082790200013 ER PT B AU Patton, ST Cowan, WD Zabinski, JS AF Patton, ST Cowan, WD Zabinski, JS GP IEEE IEEE TI Performance and reliability of a new MEMS electrostatic lateral output motor SO 1999 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM PROCEEDINGS - 37TH ANNUAL LA English DT Proceedings Paper CT 37th Annual IEEE International Reliability Physics Symposium CY MAR 23-25, 1999 CL SAN DIEGO, CA SP IEEE Electron Devices Soc, IEEE Reliabil Soc ID METAL-PARTICLE TAPES; MICROMECHANICAL STRUCTURES; MODE PERFORMANCE; SURFACE; STICTION; FRICTION AB The effect of relative humidity (RH) on the performance, reliability, and durability of a newly developed MEMS lateral output motor was determined in this study. The novel parallel plate motor design provides greater force per unit device area than comparably sized comb type actuators. Both the electrical and tribological performance of the motor were found to be dependent on RH. Electrostatic forces acting in the capacitive device were found to decrease (for a fixed voltage) with increasing RH, as well as under conditions where moisture condensed on surfaces in close proximity. The amount of adsorbed water vapor on interacting surfaces within the motor controlled performance and durability. In a dry 0.1% RH environment, excessive wear of sliding contacts and high adhesion or cold-welding of static contacts caused early failure. In moderate environments up to 50% RH, negligible wear and low adhesion were observed, and durability was over 3 orders of magnitude larger than in the dry environment. Adsorbed water films provided surface passivation and lubrication. To further illustrate the critical nature of the surface chemistry and adsorbed surface films, motors failed after about 10(5) cycles at 0.1% RH, whereas device failure was never observed for motors run as many as about 10(9) cycles at 50% RH. Above 70% RH, high static friction (stiction) forces limited dynamic performance and reliability and caused device sticking. Thus, adsorbed water is needed for surface passivation and lubrication, but too much water led to high capillary forces and stiction. By controlling and balancing surface chemistry and surface forces by adjusting the RH, excellent performance, low friction and wear, and excellent durability were attained in MEMS. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Patton, ST (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 14 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 0-7803-5220-3 PY 1999 BP 179 EP 188 DI 10.1109/RELPHY.1999.761610 PG 10 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic; Physics, Mathematical SC Computer Science; Engineering; Physics GA BM85G UT WOS:000079933100027 ER PT S AU Watson, PM Mah, MY Liou, LL AF Watson, PM Mah, MY Liou, LL BE Matloubian, M Ponti, E TI Input variable space reduction using dimensional analysis for artificial neural network modeling SO 1999 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-4 SE IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST LA English DT Proceedings Paper CT 1999 IEEE MTT-S International Microwave Symposium on the Magic Touch of Microwaves CY JUN 13-19, 1999 CL ANAHEIM, CA SP IEEE ID DESIGN AB Input variable space reduction using dimentional analysis for artificial neural network modeling of passive components is demonstrated. Results show that using dimensional analysis to limit the number of input variables significantly reduces the amount of training vectors needed for model development, which in turn decreases model development time. Also, dimensional analysis allows for determination of appropriate input variable space and leads to increased model accuracy. C1 USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Watson, PM (reprint author), USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. NR 5 TC 4 Z9 4 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-645X BN 0-7803-5135-5 J9 IEEE MTT-S PY 1999 BP 269 EP 272 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BN28P UT WOS:000081428500062 ER PT B AU Nguyen, KA Pachter, R AF Nguyen, KA Pachter, R GP NSTI TI New materials design. Free-base porphyrin and its meso-tetrahalogenated derivatives SO 1999 INTERNATIONAL CONFERENCE ON MODELING AND SIMULATION OF MICROSYSTEMS LA English DT Proceedings Paper CT 2nd International Conference on Modeling and Simulation of Microsystems CY APR 19-21, 1999 CL SAN JUAN, PR SP IEEE Electron Devices Soc, Motorola, TIMA CMP Lab, Los Alamos Natl Lab, Appl Computat Res Soc, Swiss Fed Inst Technol Lausanne, Int Assoc Math & Comp Modeling, Ibero Amer Sci & Technol Educ Consortium, Integrated Syst Engn, IntelliSense Corp, MEMSCAP SA, Mentor Graph Corp, Microcosm Technologies Inc, Mol Simulat Inc ID DENSITY FUNCTIONAL CALCULATIONS; COMPACT EFFECTIVE POTENTIALS; MOLECULAR-ORBITAL METHODS; EXPONENT BASIS-SETS; GAUSSIAN-TYPE BASIS; HALOGENATED PORPHYRINS; ORGANIC-MOLECULES; APPROXIMATION; EXCHANGE; PORPHIN AB Ab initio electronic structure theory has been applied to predict the structures and electronic spectra of free-base porphyrin (PH2) and its meso-tetrahalogenated derivatives (m-PX8H2; X = F, Cl, Br). Structures, singlet-triplet energy gaps, and electronic spectra are predicted using the B3LYP method in con unction with the 6-31G(d) basis set and the effective core potentials/basis sets of Stevens et al. Minimum energy structures of the lowest triplet excited states (T-1) were found to retain D-2h symmetry with stretched C-beta-C-beta and C-beta-C-m bond distances. We found that halogenation at the four meso-positions significantly changes the ground state excitation energies and the singlet-triplet gap for the free-base parent compound. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Nguyen, KA (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 26 TC 0 Z9 0 U1 0 U2 0 PU COMPUTATIONAL PUBLICATIONS PI CAMBRIDGE PA PUBISHING OFFICE, 308 ONE KENDALL SQ BLDG 600, CAMBRIDGE, MA 02139 USA BN 0-9666135-4-6 PY 1999 BP 57 EP 60 PG 4 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BAM65 UT WOS:000222851500013 ER PT B AU Hanna, JP Hillman, RG AF Hanna, JP Hillman, RG GP NSTI TI A common basis for mixed-technology micro-system modeling SO 1999 INTERNATIONAL CONFERENCE ON MODELING AND SIMULATION OF MICROSYSTEMS LA English DT Proceedings Paper CT 2nd International Conference on Modeling and Simulation of Microsystems CY APR 19-21, 1999 CL SAN JUAN, PR SP IEEE Electron Devices Soc, Motorola, TIMA CMP Lab, Los Alamos Natl Lab, Appl Computat Res Soc, Swiss Fed Inst Technol Lausanne, Int Assoc Math & Comp Modeling, Ibero Amer Sci & Technol Educ Consortium, Integrated Syst Engn, IntelliSense Corp, MEMSCAP SA, Mentor Graph Corp, Microcosm Technologies Inc, Mol Simulat Inc DE VHDL-AMS; MEMS; modeling; simulation AB An ad hoc working group, organized under the DARPA Composite CAD program, is developing a common set of VHDL-AMS (VHSIC Hardware Description Language for Analog and Mixed Signal) definitions for modeling mixed-technology systems. This common set of definitions will enable VHDL-AMS model interoperability, composition, and exchange. VHDL-AMS promises to provide similar benefits and infrastructure for mixed-signal (electronics) and mixed-technology (mechanical, fluidic, thermal, etc.) system design that VHDL did for the design of digital electronics. The working group is also developing a set of modeling guidelines and VHDL-AMS examples. This paper presents and discusses this joint effort between Industry, Academia, and the Government. The results of this effort will form the basis for standardization within the IEEE Design Automation Standards Committee. A common basis for model interoperability is essential to the successful application of VHDL-AMS to mixed-technology system modeling and design. C1 USAF, Res Lab, Multitechnol Integrat Branch, Griffiss AFB, NY 13441 USA. RP Hanna, JP (reprint author), USAF, Res Lab, Multitechnol Integrat Branch, 525 Brooks Rd, Griffiss AFB, NY 13441 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU COMPUTATIONAL PUBLICATIONS PI CAMBRIDGE PA PUBISHING OFFICE, 308 ONE KENDALL SQ BLDG 600, CAMBRIDGE, MA 02139 USA BN 0-9666135-4-6 PY 1999 BP 132 EP 135 PG 4 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BAM65 UT WOS:000222851500033 ER PT B AU Silversmith, DJ Reid, JR AF Silversmith, DJ Reid, JR GP NSTI TI Joule heating simulation of poly-silicon thermal micro-actuators SO 1999 INTERNATIONAL CONFERENCE ON MODELING AND SIMULATION OF MICROSYSTEMS LA English DT Proceedings Paper CT 2nd International Conference on Modeling and Simulation of Microsystems CY APR 19-21, 1999 CL SAN JUAN, PR SP IEEE Electron Devices Soc, Motorola, TIMA CMP Lab, Los Alamos Natl Lab, Appl Computat Res Soc, Swiss Fed Inst Technol Lausanne, Int Assoc Math & Comp Modeling, Ibero Amer Sci & Technol Educ Consortium, Integrated Syst Engn, IntelliSense Corp, MEMSCAP SA, Mentor Graph Corp, Microcosm Technologies Inc, Mol Simulat Inc DE MEMS; thermal actuators; Joule heating; thermal conductivity; finite element analysis ID ARRAYS AB Previous studies of surface micro-machined polycrystalline silicon MEMS thermal micro-actuators have shown that these simple devices can provide deflections on the order of 10 micrometers at CMOS compatible drive voltages. These thermo-mechanical devices operate by differential thermal expansion caused by ohmic heating in higher resistance regions of the double beam device. Because of thermal conductivity and temperature dependent resistivity in polycrystalline silicon, the temperature profile along the "pusher" section of the beam is not uniform, and motion simulation can be complex. Using a new Joule-heating finite element simulation module, reasonable agreement between simulation and near-IR microscopy on MEMS thermal actuators has been established. This work demonstrates the need to develop optimized design criteria in this class of devices to mitigate the thermal conduction and temperature variation effects in the pusher beam, which degrade displacement performance. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Silversmith, DJ (reprint author), USAF, Res Lab, 31 Grenier St, Hanscom AFB, MA 01731 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU COMPUTATIONAL PUBLICATIONS PI CAMBRIDGE PA PUBISHING OFFICE, 308 ONE KENDALL SQ BLDG 600, CAMBRIDGE, MA 02139 USA BN 0-9666135-4-6 PY 1999 BP 613 EP 616 PG 4 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Mathematics, Applied SC Engineering; Mathematics GA BAM65 UT WOS:000222851500154 ER PT B AU Ewing, RL Cabrera, EL AF Ewing, RL Cabrera, EL BE RamirezAngulo, J TI Scaling issues addressed for mixed-signal design by use of dimensional analysis methodology and VHDL-AMS SO 42ND MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS, PROCEEDINGS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 42nd Midwest Symposium on Circuits and Systems CY AUG 08-11, 1999 CL NEW MEXICO STATE UNIV, CORBETT CTR, LAS CRUCES, NM SP IEEE Circuits & Syst Soc, Klipsch Sch Elect & Comp Engn HO NEW MEXICO STATE UNIV, CORBETT CTR AB This paper looks at symbolic matrix techniques and approaches for mixed-signal design using dimensional analysis techniques or Pi parameters. Scaling and performance issues are addressed by developing dimensionless parameter models, which are parsed into the VHDL-AMS description language requirements. C1 USAF, Inst Technol, Res Lab, Div Informat Technol, Wright Patterson AFB, OH 45433 USA. RP USAF, Inst Technol, Res Lab, Div Informat Technol, Wright Patterson AFB, OH 45433 USA. EM ewingrl@sensors.wpafb.af.mil; elc00318@pegasus.cc.ucf.edu 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 BN 0-7803-5491-5; 0-7803-5492-3 PY 1999 BP 56 EP 59 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BQ78X UT WOS:000089525800014 ER PT B AU Donohoe, GW Lyke, JC AF Donohoe, GW Lyke, JC BE RamirezAngulo, J TI Adaptive computing for space SO 42ND MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS, PROCEEDINGS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 42nd Midwest Symposium on Circuits and Systems CY AUG 08-11, 1999 CL NEW MEXICO STATE UNIV, CORBETT CTR, LAS CRUCES, NM SP IEEE Circuits & Syst Soc, Klipsch Sch Elect & Comp Engn HO NEW MEXICO STATE UNIV, CORBETT CTR AB This paper describes space applications of adaptive, or reconfigurable, computing, in which a computer's architecture can be "rewired" in order to optimize itself for a particular algorithm. Benefits, challenges, and design issues ape discussed, and necessary research areas outlined. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Donohoe, GW (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 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 0-7803-5492-3 PY 1999 BP 126 EP 129 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BQ78X UT WOS:000089525800031 ER PT B AU Clark, N Furth, PM AF Clark, N Furth, PM BE RamirezAngulo, J TI Intelligent vision systems SO 42ND MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS, PROCEEDINGS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 42nd Midwest Symposium on Circuits and Systems CY AUG 08-11, 1999 CL NEW MEXICO STATE UNIV, CORBETT CTR, LAS CRUCES, NM SP IEEE Circuits & Syst Soc, Klipsch Sch Elect & Comp Engn HO NEW MEXICO STATE UNIV, CORBETT CTR AB We have developed a new approach for performing high-bandwidth adaptive optics. Our approach is based on using massively parallel analog wavefront sensing, reconstruction, and compensation. We refer to our integrated adaptive optics system as a "silicon eye" because it operates in many ways analogous to biological retinas. In addition to speed, the silicon eye offers advantages in cost, size, and power consumption. In this paper, we discuss designs for massively parallel wavefront sensors, active pixel centroid circuits, analog wavefront reconstructors, and MEMs micro-mirrors. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Clark, N (reprint author), USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5492-3 PY 1999 BP 258 EP 261 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BQ78X UT WOS:000089525800062 ER PT B AU SanGregory, SL Brothers, C Gallagher, D Siferd, R AF SanGregory, SL Brothers, C Gallagher, D Siferd, R BE RamirezAngulo, J TI A fast, low-power logarithm approximation with CMOS VLSI implementation SO 42ND MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS, PROCEEDINGS, VOLS 1 AND 2 LA English DT Proceedings Paper CT 42nd Midwest Symposium on Circuits and Systems CY AUG 08-11, 1999 CL NEW MEXICO STATE UNIV, CORBETT CTR, LAS CRUCES, NM SP IEEE Circuits & Syst Soc, Klipsch Sch Elect & Comp Engn HO NEW MEXICO STATE UNIV, CORBETT CTR AB A new technique and CMOS VLSI implementation for computing approximate logarithms (base 2, and 10) for binary integers is presented. The approximation is performed using only combinational logic and requires no multiplications. Additionally, as implemented a ROM of only N X log(2) (N) bits is used to convert N bit integers. The maximum error of the approximation is 1.5% when the input value is 3, and decays exponentially to less than 0.5% for input values greater than 25. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP SanGregory, SL (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 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 BN 0-7803-5492-3 PY 1999 BP 388 EP 391 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BQ78X UT WOS:000089525800093 ER PT S AU Carlisle, MC AF Carlisle, MC GP ASSOC COMPUTING MACHINERY ASSOC COMPUTING MACHINERY ASSOC COMPUTING MACHINERY TI A truly implementation independent GUI development tool SO ACM SIGADA ANNUAL INTERNATIONAL CONFERENCE (SIGADA'99) - PROCEEDINGS SE ADA LETTERS LA English DT Proceedings Paper CT ACM SIGADA Annual International Conference (SIGADA 99) CY OCT 17-21, 1999 CL REDONDO BEACH, CA SP ACM Special Interest Grp Ada, Ada Europe, ACM SIGAPP, ACM SIGBIO, ACM SIGCAS, ACM SIGSE, ACM SIGPLAN, ACM SIGSOFT DE graphical user interfaces; automatic code generation; Tcl/Tk; Java; Ada AB Over the last few years, graphical user interface programming has become increasingly prevalent. Many libraries and languages have been developed to simplify this task. Additionally, design tools have been created that allow the programmer to "draw" their desired interface and then have code automatically generated. Unfortunately, use of these tools locks the programmer into a particular implementation. Even if the tool targets a multi-platform library (e.g. Tcl/Tk or JVM), the flexibility of the result is constrained. We present a truly implementation and platform independent solution. RAPID generates Ada code targeted to an object-oriented set of graphical user interface specifications with absolutely no implementation dependent information. The pattern used to derive these specifications is an improvement over the "Abstract Factory" Pattern, as it allows both the specification and implementation to take advantage of inheritance. The user can then select an implementation (for example, Tcl/Tk or JVM) at compile time. RAPID itself is also written using the same specifications; therefore it requires no modification to target a new implementation or to use a new implementation itself. RAPID is currently being used to design the user interface for a satellite ground station. C1 USAF Acad, Dept Comp Sci, Colorado Springs, CO 80840 USA. RP Carlisle, MC (reprint author), USAF Acad, Dept Comp Sci, 2354 Fairchild Dr,Suite 6K41, Colorado Springs, CO 80840 USA. NR 12 TC 0 Z9 0 U1 1 U2 1 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036-9998 USA SN 1094-3641 BN 1-58113-127-5 J9 ADA LETTERS PY 1999 VL 19 IS 3 BP 47 EP 52 PG 4 WC Computer Science, Software Engineering SC Computer Science GA BN91K UT WOS:000083442700008 ER PT J AU Niall, KK AF Niall, KK TI Estimates of shape by eye, or, The little invariant that could SO ACTA PSYCHOLOGICA LA English DT Article DE visual perception; form and shape perception; linear perspective; perceptual measures; visual acuity; mathematical psychology ID PROJECTIVE INVARIANCE; OBJECT RECOGNITION; DISCRIMINATION; PERCEPTION AB Five experiments were conducted to test the hypothesis that observers apprehend specific constancies under change in perspective. The constancies were projective properties of ellipses pictured to slant and tilt in depth. Observers were asked to reproduce the static upright view of a moving pair of ellipses, using a computer graphics display and interface. Projective invariants for pairs of conics were computed on the observers' productions. A few experimental conditions revealed near-perfect performance. When pairs of coplanar ellipses were viewed under dynamic transformation in perspective, then invariants calculated on the observers' productions were a match - in value on average - to the invariants of the transforming ellipse pairs. It is proposed that measures of projective properties afford a family of techniques that can be applied to gauge acuity for complex shapes in the study of visual form perception. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, AL HRAE, Mesa, AZ 85206 USA. RP Niall, KK (reprint author), USAF, Res Lab, AL HRAE, 6001 S Power Rd,Bldg 558, Mesa, AZ 85206 USA. NR 27 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0001-6918 J9 ACTA PSYCHOL JI Acta Psychol. PD JAN PY 1999 VL 100 IS 3 BP 291 EP 320 DI 10.1016/S0001-6918(98)00042-0 PG 30 WC Psychology, Experimental SC Psychology GA 150CA UT WOS:000077644200005 PM 9894691 ER PT S AU Burke, WJ Gough, MP Gentile, LC Huang, CY Machuzak, JS Rubin, AG AF Burke, WJ Gough, MP Gentile, LC Huang, CY Machuzak, JS Rubin, AG BE James, HG Raitt, WJ Sultzer, MP TI MHz and kHz modulations of particle fluxes during beam experiments of the tethered satellite system missions SO ACTIVE EXPERIMENTS IN SPACE PLASMAS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT D0 8 Symposium of COSPAR Scientific Commission D Held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Int Union Radio Sci, Comm Space Res ID SPACELAB-2 ELECTRON-BEAM; WHISTLER-MODE RADIATION; TSS 1R; WAVES; OPERATIONS; FREQUENCY; FIELD AB Modulations of electron and ion fluxes in the frequency ranges 0 - 10 MHz and 0 - 10 kHz were monitored by the Shuttle Potential and Return Electron Experiment (SPREE) during electron beam experiments conducted on the Tethered Satellite System missions. Electron fluxes detected by SPREE were modulated at megahertz frequencies only when beams were emitted at large pitch angles with respect to the Earth's magnetic field. High frequency modulations fall into two classes close to: (1) even or odd half harmonics of the electron gyrofrequency if beam pitch angle alpha(B) approximate to 90 degrees, and (2) harmonics of estimated plasma frequencies if 60 degrees > alpha(B) > 45 degrees. When SPREE intercepted beam electrons after one gyrotum, they were modulated at the same frequencies as secondary electrons. These measurements indicate that beam electrons propagate in cylindrical shells whose inner edge is marked by steep spatial gradients in fluxes of beam electrons. Inside the shell, electron distribution functions have positive velocity space slopes at energies near that of the beam. These gradients act as free energy sources to drive cavity modes that alter the instantaneous guiding centers of electrons causing SPREE to sample alternating parts of the beam cylinder's inner edge. Associated time-varying electric fields also modulated the fluxes of secondary electrons reaching SPREE. Low kilohertz modulations, detected at all beam pitch angles, correspond to no natural plasma mode and are interpreted as signatures of large-amplitude, ion acoustic-like waves excited through Cerenkov interactions between electron beams and ambient plasmas as the shuttle moved at supersonic speeds across the ionosphere. This hypothesis is confirmed by the simultaneous detection of electrons and ions modulated at the same frequencies when the shuttle was negatively charged. These results explain the sources of coherent whistler and ion acoustic-like waves detected during electron beam experiments of Spacelab 2. (C) 1999 COSPAR. Published by Elsevier Science Ltd. C1 USAF, Res Lab, Bedford, MA 01731 USA. Univ Sussex, Ctr Space Sci, Brighton BN1 9QT, E Sussex, England. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA. RP Burke, WJ (reprint author), USAF, Res Lab, 29 Randolph Rd, Bedford, MA 01731 USA. NR 21 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES PY 1999 VL 24 IS 8 BP 1047 EP 1054 DI 10.1016/S0273-1177(99)00552-9 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP17V UT WOS:000084336900013 ER PT S AU Barchers, JD Brown, JM AF Barchers, JD Brown, JM BE Tyson, RK Fugate, RQ TI Real-time adaptive optimization of track loop controllers in adaptive optics systems as a function of input statistics and sensor gain SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE optimal track bandwidth; adaptive optics; recursive least squares ID PERFORMANCE; TURBULENCE AB The optimal track loop controller in an adaptive optics system is a function of the steering mirror dynamics, the temporal statistics of the input disturbance signal (mount jitter and atmospheric), measurement noise, and the sensor gain. The atmospheric input statistics and the sensor gain of a quadrant detector are slowly time-varying on a scale of minutes. If all parameters are known a priori, the analytical optimal controller is found by augmenting the dynamics of the input disturbance spectra and solving an Hz optimization problem (i.e. LQG/LTR). Near optimal control is achieved by augmenting the mount jitter dynamics and a first order approximation of the atmosphere dynamics and finding the LQG/LTR controller. The optimal bandwidth to compensate for time-varying atmospheric disturbance and noise levels is found by optimizing the loop gain. Recursive least squares (RLS) is used to estimate the sensor gain and optimize the bandwidth in real time. The only measurements necessary for optimization are the residual track errors from a high frame rate, low noise quad cell algorithm and from a low frame rate dense ccd array using a centroid algorithm. Provided the temporal variations in the sensor gain are slow, closed loop robust stability is guaranteed by constraining the optimization algorithm via projection. Simulation results are presented which verify that the constrained optimal controller is achieved under a variety of conditions. C1 USAF, Res Lab, DES, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Barchers, JD (reprint author), USAF, Res Lab, DES, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 14 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 0-8194-3248-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3762 BP 77 EP 90 DI 10.1117/12.363563 PG 14 WC Optics SC Optics GA BN95E UT WOS:000083637400009 ER PT S AU Barchers, JD Ellerbroek, BL AF Barchers, JD Ellerbroek, BL BE Tyson, RK Fugate, RQ TI Power series evaluation of Zernike covariances for turbulence-induced phase distortions including outer scale and servo lag effects SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE Zernike polynomials; turbulence outer scale; automated solution; adaptive optics; Mellin transforms ID ATMOSPHERIC-TURBULENCE; ADAPTIVE-OPTICS; EXPANSION COEFFICIENTS; COMPENSATION; PERFORMANCE AB Mellin transform techniques are applied to develop power series formulas to efficiently evaluate covariances for zernike representations of turbulence-induced phase distortions along a pair of ray paths through the atmosphere from one or several sources at finite or infinite range. The formulas also apply when the phase distortions are temporally filtered by a closed loop adaptive optics system. The power series formulas are developed using an automated computer logic algorithm designed to solve multiple contour integrals in multiple complex planes resulting from the application of Mellin transform techniques. Results are presented for the von Karman turbulence spectrum with a finite outer scale. Amplitude scintillation effects are neglected. The Taylor hypothesis is assumed to model the temporal behavior of the turbulence using either a fixed or random wind profile. The resulting formulas are weighted integrals of the refractive index structure constant C-n(2)(z), where the weighting functions are power series in from one to six indices depending on the beacons used and the choices made regarding the atmospheric turbulence spectrum and the direction of the wind. C1 USAF, Res Lab, DES, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Barchers, JD (reprint author), USAF, Res Lab, DES, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 17 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 0-8194-3248-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3762 BP 125 EP 139 DI 10.1117/12.363568 PG 15 WC Optics SC Optics GA BN95E UT WOS:000083637400014 ER PT S AU Rhoadarmer, TA McGuire, PC Hughes, JM Lloyd-Hart, M Angel, JRP Schaller, S Kenworthy, MA AF Rhoadarmer, TA McGuire, PC Hughes, JM Lloyd-Hart, M Angel, JRP Schaller, S Kenworthy, MA BE Tyson, RK Fugate, RQ TI Laboratory adaptive optics system for testing the wave front sensor for the new MMT SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE adaptive optics; wave front sensors; deformable mirrors; generating turbulence; Kolmogorov phase plates ID ATMOSPHERIC-TURBULENCE; OPTIMIZATION AB A laboratory adaptive optics system has been built for testing the wave front sensor hardware and software for the new Multiple Mirror Telescope adaptive optics system. The system will also allow different wave Gent reconstruction and prediction schemes to be examined. The laboratory system contains a silicon micromachined adaptive mirror with 37 electro-static actuators as well as a novel approach for generating atmospheric turbulence. The design and initial testing of the system are presented. C1 USAF, Res Lab, AFRL, DES, Kirtland AFB, NM 87117 USA. RP Rhoadarmer, TA (reprint author), USAF, Res Lab, AFRL, DES, Kirtland AFB, NM 87117 USA. RI McGuire, Patrick/D-2962-2013; OI McGuire, Patrick/0000-0001-6592-4966; Kenworthy, Matthew/0000-0002-7064-8270 NR 20 TC 4 Z9 4 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 0-8194-3248-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3762 BP 161 EP 173 DI 10.1117/12.363571 PG 13 WC Optics SC Optics GA BN95E UT WOS:000083637400017 ER PT S AU Christou, JC Jefferies, SM Hege, EK AF Christou, JC Jefferies, SM Hege, EK BE Tyson, RK Fugate, RQ TI Object independent point spread function and wavefront phase estimation SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE adaptive optics; astronomy; image post processing; deconvolution; blind deconvolution; wavefront reconstruction ID BLIND DECONVOLUTION; ASTRONOMICAL IMAGES; RESTORATION AB We demonstrate the recovery, without a priori object knowledge, of the unknown object and point spread functions (PSFs) from multiframe focal-plane data. By modeling the object Fourier spectrum as an unprejudiced linear combination of the cross-spectra of the measurements and the PSFs, we significantly reduce the number of degrees-of-freedom for the blind deconvolution problem. C1 USAF, Res Lab, AFRL, DES,Starfire Opt Range, Kirtland AFB, NM 87117 USA. RP Christou, JC (reprint author), USAF, Res Lab, AFRL, DES,Starfire Opt Range, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 12 TC 3 Z9 3 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 0-8194-3248-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3762 BP 201 EP 210 DI 10.1117/12.363575 PG 10 WC Optics SC Optics GA BN95E UT WOS:000083637400021 ER PT S AU Ellerbroek, BL Lee, DJ Barchers, JD AF Ellerbroek, BL Lee, DJ Barchers, JD BE Tyson, RK Fugate, RQ TI Analysis of atmospheric turbulence measurements obtained with the Starfire Optical Range 3.5-meter telescope adaptive optical system SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE adaptive optics; atmospheric turbulence characterization ID PERFORMANCE AB The adaptive optical system for the Starfire Optical Range 3.5-meter telescope includes a Shack-Hartmann wavefront sensor (WFS) with 30 by 30 subapertures and a continuous facesheet deformable mirror (DM) with 31 by 31 actuators within the telescope aperture. Time histories of turbulence-induced phase distortions have been estimated from WFS gradient measurements and DM actuator commands acquired simultaneously with the adaptive optics loop closed. The statistics of these phase distortion profiles have been characterized in terms of spatial structure functions, Zernike coefficient statistics, and temporal power spectral densities. The results obtained are in good agreement with predictions based upon Kolmogorov theory. C1 USAF, Res Lab, DES, Directed Energy Directorate,Starfire Opt Range, Kirtland AFB, NM 87117 USA. RP Ellerbroek, BL (reprint author), USAF, Res Lab, DES, Directed Energy Directorate,Starfire Opt Range, Kirtland AFB, NM 87117 USA. NR 7 TC 2 Z9 2 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 0-8194-3248-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3762 BP 212 EP 224 DI 10.1117/12.363576 PG 13 WC Optics SC Optics GA BN95E UT WOS:000083637400022 ER PT S AU Barchers, JD Lee, DJ Lane, DE AF Barchers, JD Lee, DJ Lane, DE BE Tyson, RK Fugate, RQ TI Single-input-single-output analysis of latency and quadrant detector saturation in adaptive optical systems SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE optimal bandwidth; latency; adaptive optics ID PERFORMANCE; TURBULENCE AB Feedback control theory offers several useful tools for analysis of adaptive optics systems. The basic tools of single-input-single-output analysis are applied to design first order and optimal filters for a specific loop bandwidth or gain margin as a function of latency and sample rate. Optimizing filter loop band-width as a function of temporal disturbance and noise statistics is addressed with respect to the internal model principle. Latency, due to camera readout and processing time, is shown to be the primary design driver for optimal AO system performance. The effects of wavefront sensor saturation are discussed and simulation and experimental results are presented. C1 USAF, Res Lab, DES, Starfire Opt Range,Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Barchers, JD (reprint author), USAF, Res Lab, DES, Starfire Opt Range,Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 12 TC 1 Z9 1 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 0-8194-3248-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3762 BP 308 EP 320 DI 10.1117/12.363587 PG 13 WC Optics SC Optics GA BN95E UT WOS:000083637400032 ER PT S AU Fingers, RT Rubertus, CS AF Fingers, RT Rubertus, CS BE Coey, M Lewis, LH Ma, BM Schrefl, T Schultz, L Fidler, J Harris, VG Hasegawa, R Inoue, A McHenry, M TI Air Force application of advanced magnetic materials SO ADVANCED HARD AND SOFT MAGNETIC MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT 1999 MRS Spring Meeting CY APR 05-09, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc AB A national initiative is underway to develop and test a more electric aircraft (MEA) and is being led by the U.S. Air Force Research Laboratory at Wright-Patterson Air Force Base, Ohio. The MEA concept is based on utilizing electric power to drive aircraft subsystems which are currently driven by a combination of hydraulic, pneumatic, electric and mechanical power transfer systems. A major objective of this effort is to increase military aircraft reliability, maintainability and supportability and to drastically reduce the need for ground support equipment. These improvements will be realized through the further advancement of key MEA technologies, including magnetic bearings, aircraft integrated power units (IPU), and starter/generators (IS/G) internal to an aircraft main propulsion engine. These advanced developments, as well as weapon and space power applications, are the driving force for the new emphasis on high temperature and high strength magnetic materials for power applications. In determining the best magnetic material for an application it is typically necessary to conduct an engineering trade-off analysis which takes into consideration mechanical behavior, electrical loss, and magnetic properties under the conditions of actual usage. New materials solutions are required to meet these challenges, as designers often find the magnetic material performance to be the technological limitation. C1 USAF, Res Lab, Prop Directorate, Wright Patterson AFB, OH 45433 USA. RP Fingers, RT (reprint author), USAF, Res Lab, Prop Directorate, Wright Patterson AFB, OH 45433 USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-485-8 J9 MATER RES SOC SYMP P PY 1999 VL 577 BP 481 EP 486 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA BP16T UT WOS:000084261000054 ER PT S AU Suter, BW Lindsey, AR AF Suter, BW Lindsey, AR BE Luk, FT TI Convolution theorems: Partitioning the space of integral transforms, Part II SO ADVANCED SIGNAL PROCESSING ALGORITHMS, ARCHITECTURES,AND IMPLEMENTATIONS IX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Signal Processing Algorithms, Architectures, and Implementations IX CY JUL 19-21, 1999 CL DENVER, CO SP SPIE AB Investigating a number of different integral transforms uncovers distinct patterns in the type of scale-based convolution theorems afforded by each. It is shown that scaling convolutions behave in quite a similar fashion to translational convolution in the transform domain, such that the many diverse transforms have only a few different forms for convolution theorems. The hypothesis is put forth that the space of integral transforms is partitionable based on these forms. C1 USAF, Res Lab, IFGC, Rome, NY 13441 USA. RP Suter, BW (reprint author), USAF, Res Lab, IFGC, 525 Brooks Rd, Rome, NY 13441 USA. NR 9 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 0-8194-3293-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3807 BP 534 EP 545 DI 10.1117/12.367670 PG 12 WC Engineering, Electrical & Electronic; Mathematics, Applied SC Engineering; Mathematics GA BP45Z UT WOS:000085205800051 ER PT S AU Teehan, RF Bienfang, JC Denman, CA AF Teehan, RF Bienfang, JC Denman, CA BE Fejer, MM Injeyan, H Keller, U TI High spectral brightness laser at 1.06 mu m SO ADVANCED SOLID-STATE LASERS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY JAN 31-FEB 03, 1999 CL BOSTON, MA SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc AB Power scaling and frequency stabilization efforts yield a 24 Watt TEK0.0, injection-locked output at 1.064 mum with a spectral linewidth of 1.6 Hz. C1 USAF, Res Lab, DELO, Kirtland AFB, NM 87117 USA. RP Teehan, RF (reprint author), USAF, Res Lab, DELO, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. RI Bienfang, Joshua/A-7285-2010 NR 6 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-583-8 J9 OSA TRENDS OPT PHOTO PY 1999 VL 26 BP 222 EP 227 PG 6 WC Materials Science, Characterization & Testing; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BT71N UT WOS:000173833200046 ER PT S AU Dubinskii, MA Schepler, KL Abdulsabirov, RY Semashko, VV Naumov, AK Korableva, SL AF Dubinskii, MA Schepler, KL Abdulsabirov, RY Semashko, VV Naumov, AK Korableva, SL BE Fejer, MM Injeyan, H Keller, U TI Nd3+: YF3 as a laser material for CW diode pumped operation SO ADVANCED SOLID-STATE LASERS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY JAN 31-FEB 03, 1999 CL BOSTON, MA SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc ID ULTRAVIOLET-LASER C1 USAF, Res Lab, AFRL, SNJT, Wright Patterson AFB, OH 45433 USA. RP Dubinskii, MA (reprint author), USAF, Res Lab, AFRL, SNJT, 2700 S St Suite 2, Wright Patterson AFB, OH 45433 USA. RI Korableva, Stella/L-7304-2015; Semashko, Vadim/P-8360-2015; Naumov, Alexander/A-1581-2014 OI Korableva, Stella/0000-0002-8469-2512; Naumov, Alexander/0000-0003-2421-7602 NR 7 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-583-8 J9 OSA TRENDS OPT PHOTO PY 1999 VL 26 BP 303 EP 305 PG 3 WC Materials Science, Characterization & Testing; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BT71N UT WOS:000173833200060 ER PT S AU McKay, J Schepler, KL Catella, G AF McKay, J Schepler, KL Catella, G BE Fejer, MM Injeyan, H Keller, U TI Kilohertz, 2.6-mu m Cr2+: CdSe laser SO ADVANCED SOLID-STATE LASERS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY JAN 31-FEB 03, 1999 CL BOSTON, MA SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc AB This paper describes a 2-mum pumped, kilohertz repetition rate, Cr2+:CdSe laser producing 500 mW of broadband output centered at 2.6 gm with 48% absorbed power conversion efficiency. With a larger pump beam to prevent coating damage, 815 mW was demonstrated. C1 USAF, Res Lab, SNJT, Wright Patterson AFB, OH 45433 USA. RP McKay, J (reprint author), USAF, Res Lab, SNJT, 3109 P St, Wright Patterson AFB, OH 45433 USA. NR 6 TC 11 Z9 11 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-583-8 J9 OSA TRENDS OPT PHOTO PY 1999 VL 26 BP 420 EP 426 PG 7 WC Materials Science, Characterization & Testing; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BT71N UT WOS:000173833200083 ER PT S AU Dinndorf, KM Miller, H Tabirian, A Jenssen, HP Cassanho, A AF Dinndorf, KM Miller, H Tabirian, A Jenssen, HP Cassanho, A BE Fejer, MM Injeyan, H Keller, U TI Two micron diode-pumped laser operation of Tm, Ho : BaY2F8 SO ADVANCED SOLID-STATE LASERS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY JAN 31-FEB 03, 1999 CL BOSTON, MA SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc AB BaY2F8 is a promising host material for applications in solid-state laser systems. It is a birefringent material that is optically transparent from its infrared absorption edge at 9 mum to beyond 200 nm in the ultraviolet[1]. Its phonon spectra is relatively low energy, with a maximum of 415 cm(-1)[2], and it has low non-radiative relaxation rates relative to garnets[3]. These characteristics make it potentially attractive for mid-infrared energy storage applications. C1 USAF, Res Lab, DELO, Kirtland AFB, NM USA. RP Dinndorf, KM (reprint author), USAF, Res Lab, DELO, Kirtland AFB, NM USA. NR 13 TC 2 Z9 2 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-583-8 J9 OSA TRENDS OPT PHOTO PY 1999 VL 26 BP 506 EP 511 PG 6 WC Materials Science, Characterization & Testing; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BT71N UT WOS:000173833200098 ER PT S AU Moore, GT Koch, K AF Moore, GT Koch, K BE Fejer, MM Injeyan, H Keller, U TI Nonresonant recirculation configurations for optical frequency doubling and tripling SO ADVANCED SOLID-STATE LASERS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY JAN 31-FEB 03, 1999 CL BOSTON, MA SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc AB We describe how nonresonant recirculation can be used to enhance the efficiency of second-harmonic and third-harmonic generation, as compared to single-pass harmonic generation. Up to four times the doubling efficiency is expected at low pump power. Generated peak harmonic power can exceed that of the pump. The optimized sum-frequency crystal length is shorter for the recirculated configurations than the single-pass triplers. C1 USAF, Res Lab, Directed Energy Directorate, AFRL,DELO, Kirtland AFB, NM 87117 USA. RP Moore, GT (reprint author), USAF, Res Lab, Directed Energy Directorate, AFRL,DELO, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-583-8 J9 OSA TRENDS OPT PHOTO PY 1999 VL 26 BP 599 EP 607 PG 9 WC Materials Science, Characterization & Testing; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BT71N UT WOS:000173833200117 ER PT S AU Denman, CA Libby, SI AF Denman, CA Libby, SI BE Fejer, MM Injeyan, H Keller, U TI Birefringence compensation using a single Nd : YAG rod SO ADVANCED SOLID-STATE LASERS SE OSA TRENDS IN OPTICS AND PHOTONICS LA English DT Proceedings Paper CT Topical Meeting on Advanced Solid-State Lasers CY JAN 31-FEB 03, 1999 CL BOSTON, MA SP Opt Soc Amer, IEEE, Lasers & Electro Opt Soc AB We model and experimentally verify a single pump-head implementation of a birefringence compensation scheme. A reduction of depolarization loss by as much as 84% was observed. C1 USAF, Res Lab, Solid State Lasers & Non Linear Opt Branch, Kirtland AFB, NM 87117 USA. RP Denman, CA (reprint author), USAF, Res Lab, Solid State Lasers & Non Linear Opt Branch, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 6 TC 11 Z9 11 U1 0 U2 1 PU OPTICAL SOC AMERICA PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-5695 BN 1-55752-583-8 J9 OSA TRENDS OPT PHOTO PY 1999 VL 26 BP 608 EP 612 PG 5 WC Materials Science, Characterization & Testing; Optics; Physics, Applied SC Materials Science; Optics; Physics GA BT71N UT WOS:000173833200118 ER PT S AU Radsick, T Saruhan, B Schneider, H AF Radsick, T Saruhan, B Schneider, H BE Singh, JP Bansal, NP TI Non-conventional, damage tolerant oxide oxide fiber-composites SO ADVANCES IN CERAMIC MATRIX COMPOSITES IV SE CERAMIC TRANSACTIONS LA English DT Proceedings Paper CT 100th Annual Meeting of the American-Ceramic-Society CY MAY 03-06, 1998 CL CINCINNATI, OH SP Amer Ceram Soc ID CERAMIC-COMPOSITE; INTERFACES; MULLITE AB A fiber-reinforced ceramic composite was developed using matrix-infiltrated and non-infiltrated fiber layers. Fiber interface coatings were not used. Processed layers were hot-pressed together resulting in an oxide-fiber (Nextel720), oxide-matrix (mullite) composite. Matrix slurries were prepared using submicron-sized alpha-Al2O3 powder coated with amorphous SiO2, along with additives to decrease mullite-formation temperature. Room temperature 3-point bend tests were conducted on as-received samples and samples exposed to long-term, high-temperature oxidation. Composites demonstrate both reasonable fracture strength and damage tolerance. The favorable thermo-mechanical behavior can be explained by the composite's laminate-type structure. Matrix-infiltrated fiber layers provide strength but behave in a brittle, quasi-monolithic manner. Non-infiltrated fiber layers connect infiltrated layers, and provide damage tolerance through in-plane crack deflection and crack bridging. Varying matrix-to-fiber ratio allows tailoring of composite properties, trading off strength for damage tolerance. These composites provide damage tolerant behavior in the absence of fiber interface coatings, and when using a matrix which bonds strongly to fibers. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Radsick, T (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 1042-1122 BN 1-57498-059-9 J9 CERAM TRANS PY 1999 VL 96 BP 173 EP 181 PG 9 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN02T UT WOS:000080431200015 ER PT S AU Von Mayrhauser, A Mraz, R AF Von Mayrhauser, A Mraz, R BE Zelkowitz, MV TI Using domain models for system testing SO ADVANCES IN COMPUTERS, VOL 49 SE Advances in Computers LA English DT Article ID PARTITION C1 Colorado State Univ, Dept Comp Sci, Ft Collins, CO 80523 USA. USAF Acad, Dept Comp Sci, Colorado Springs, CO 80841 USA. RP Colorado State Univ, Dept Comp Sci, Ft Collins, CO 80523 USA. EM avm@handel.cs.colorado.edu NR 43 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER ACADEMIC PRESS INC PI SAN DIEGO PA 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495 USA SN 0065-2458 BN 0-12-012149-2 J9 ADV COMPUT JI Adv. Comput. PY 1999 VL 49 BP 143 EP 190 PG 48 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA BN74V UT WOS:000082795800004 ER PT S AU Lang, M AF Lang, M BE McClung, RC Newman, JC TI Description of load interaction effects by the Delta K-eff concept SO ADVANCES IN FATIGUE CRACK CLOSURE MEASUREMENT AND ANALYSIS: VOL 2 SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 2nd Symposium on Advances in Fatigue Crack Closure Measurement and Analysis CY NOV 12-13, 1997 CL SAN DIEGO, CA SP ASTM, Comm Fatigue & Fracture E8 DE fatigue crack propagation; load interaction; overload effect; residual stresses; crack closure; compression loading ID CRACK CLOSURE AB An experimental study of load interaction effects in Al 7475-T7351 is presented. The crack propagation stress intensity factor, K-PR, was determined after different overload sequences, also involving subsequent compression loading. The results of these experiments demonstrate that the single overload can be described by single function, which describes the unloading process after the overload. One main conclusion is that load interaction effects are governed by residual compressive stresses in front of the crack tip, while crack closure plays a minor role. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Lang, M (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 32 TC 12 Z9 12 U1 1 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 0-8031-2611-5 J9 AM SOC TEST MATER PY 1999 VL 1343 BP 207 EP 223 DI 10.1520/STP15759S PG 17 WC Engineering, Mechanical; Metallurgy & Metallurgical Engineering; Microbiology SC Engineering; Metallurgy & Metallurgical Engineering; Microbiology GA BP02P UT WOS:000083908200013 ER PT B AU Pachter, M Nardi, S AF Pachter, M Nardi, S BE Tzafestas, SG TI Stochastic modeling in GPS estimation SO ADVANCES IN INTELLIGENT SYSTEMS: CONCEPTS, TOOLS AND APPLICATIONS SE INTERNATIONAL SERIES ON MICROPROCESSOR-BASED AND INTELLIGENT SYSTEMS ENGINEERING LA English DT Proceedings Paper CT 3rd European Robotics, Intelligent Systems and Control Conference (EURISCON 99) CY JUN 22-25, 1998 CL ATHENS, GREECE ID EQUATIONS C1 USAF, Inst Technol, Dept Elect & Comp Engn, ENG, Wright Patterson AFB, OH 45433 USA. RP Pachter, M (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, ENG, Wright Patterson AFB, OH 45433 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS BN 0-7923-5966-6 J9 INT S MICRO PY 1999 VL 21 BP 389 EP 400 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods SC Computer Science GA BP49T UT WOS:000085323900035 ER PT B AU De Long, HC Mitchell, JA Trulove, PC AF De Long, HC Mitchell, JA Trulove, PC BE GauneEscard, M TI Investigations of the electrodeposition of aluminum-manganese alloys from room temperature chloroaluminate molten salts SO ADVANCES IN MOLTEN SALTS: FROM STRUCTURAL ASPECT TO WASTE PROCESSING LA English DT Proceedings Paper CT European Research Conference on Molten Salts CY JUN 27-JUL 03, 1998 CL PORQUEROLLES ISL, FRANCE SP European Sci Fdn, USA, European Off, US Aerosp, USN, CNRS, Univ Provence Marseille, French Embassy Moscow, French Embassy Washington, IUSTI, CODATA, MOLTECH DE electrodeposition; molten salts; EQCM; aluminum and magnesium ID IONIC LIQUIDS; CORROSION; PHASE AB The electrochemical reduction of manganese (Il) in acidic AICl(3):EMIC (aluminum chloride:1-ethyl-3-methylimidazolium chloride) room temperature molten salt results in codeposition of aluminum and manganese. Constant potential deposition in the region of the reduction peak results in the deposition of manganese rich amorphous manganese-aluminum alloys. Constant potential deposition in the region of diffusion control results in the formation of aluminum rich amorphous manganese-aluminum alloys. We have employed an Electrochemical Quartz Crystal Microbalance (EQCM) to investigate, in situ, the deposition and stripping behavior of Al and AI-Mx in acidic AlCl(3):EMIC molten salts. The EQCM provides both mass and charge data during electrodeposition and stripping processes. This information can be used to determine codeposited metal composition and to model deposition and/or stripping processes. C1 USAF, Off Sci Res, Bolling AFB, Washington, DC 20332 USA. RP De Long, HC (reprint author), USAF, Off Sci Res, Bolling AFB, Washington, DC 20332 USA. NR 23 TC 1 Z9 1 U1 1 U2 1 PU BEGELL HOUSE, INC PI NEW YORK PA 145 MADISON AVE, NEW YORK, NY 10016 USA BN 1-56700-142-4 PY 1999 BP 137 EP 148 PG 4 WC Chemistry, Applied; Chemistry, Physical; Electrochemistry; Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter SC Chemistry; Electrochemistry; Physics GA BP10P UT WOS:000084132700012 ER PT B AU Erwin, RS Qassim, K AF Erwin, RS Qassim, K GP AIAA AIAA TI The ACTEX-I Guest Investigator program: Lessons learned and future opportunities SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB This paper presents a review of the Air Force Research Laboratory (AFRL) Advanced Controls Technology Experiment (ACTEX-I) Guest Investigator (GI) program. Focusing on lessons learned from the program, the paper will provide the AFRL perspective on positive and negative points of the program. The paper will give a description of the next AFRL GI opportunity, the Satellite Ultraquiet Isolation Experiment (SUITE), due to be launched in the Fall of 1999. The SUITE GI program will address several shortcomings that were identified with the ACTEX-I program both in the flight hardware capabilities and in the planning and execution of the GI program itself. C1 USAF, Res Lab, Space Vehicles Directorate, AFRL VSDV, Kirtland AFB, NM 87117 USA. RP Erwin, RS (reprint author), USAF, Res Lab, Space Vehicles Directorate, AFRL VSDV, Bldg 472,3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 1 EP 7 PG 7 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000001 ER PT B AU Naidu, DS Buffington, JL Banda, SS AF Naidu, DS Buffington, JL Banda, SS GP AIAA AIAA TI Further results on nondimensional forms for singularly perturbed structures SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut ID MATCHED ASYMPTOTIC EXPANSIONS AB In most of the aerospace applications, based on the knowledge of the speed of the state variables and previous experience in working with particular problems, a singularly perturbed structure is assumed by artificial insertion of a small unit-valued parameter with highest derivative or some of the state variables of the dynamical equations. However, attempts have been made to identify the singular perturbation structure in terms of the parameters of the dynamical system leading to a natural occurrence of the small parameter. In this paper, some more results are explored in identifying the singular perturbation parameter by using nondimensional forms for the dynamical equations. In particular, different structures of identifying: the singular perturbation parameter are presented and the various features of these structures are discussed. C1 USAF, Wright Patterson AFB, OH 45433 USA. RP Naidu, DS (reprint author), USAF, Wright Patterson AFB, OH 45433 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 226 EP 236 PG 11 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000024 ER PT B AU Schumacher, CJ Cottrill, GC Yeh, HH AF Schumacher, CJ Cottrill, GC Yeh, HH GP AIAA AIAA TI Optimal sliding mode flight control SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut ID AIRCRAFT MANEUVER; SYSTEMS AB This paper presents an optimal sliding mode control design method for a nonlinear system with a "cascade" or two-loop structure. The outer loop is designed using a Stare Dependent Riccati Equation optimal controller. This outer loop controller generates an optimal sliding surface which is followed by a sliding mode controller in the inner loop. The control design method is demonstrated on a nonlinear model of an F-16 aircraft. Simulation results show excellent command tracking and robustness, with substantial errors in aerodynamic coefficients having little effect on command tracking or stability. The results presented in this paper indicate that the combination of an SDRE controller in the outer loop and a sliding mode controller in the inner loop has a great deal of promise for nonlinear robust control. C1 USAF, Res Lab, AFRL, VAAD, Wright Patterson AFB, OH 45433 USA. RP Schumacher, CJ (reprint author), USAF, Res Lab, AFRL, VAAD, 2210 8th St, Wright Patterson AFB, OH 45433 USA. NR 7 TC 1 Z9 1 U1 1 U2 1 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 435 EP 443 PG 9 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000045 ER PT B AU Pachter, M Chandler, PR Nelson, E Rasmussen, S AF Pachter, M Chandler, PR Nelson, E Rasmussen, S GP AIAA AIAA TI Parameter estimation for over-actuated aircraft with nonlinear aerodynamics SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB The static system identification scheme for reconfigurable flight control is modified to encompass over-actuated aircraft with nonlinear aerodynamics. The first step is to obtain a reliable estimate of the critical equivalent loop gain and stability derivative in the respective pitch, yaw, and roll control channels. Short data windows are used so that the system identification algorithm operates in "real-time" and reconfigurable control is feasible. Moreover, excitation enhancing control signals are not used in this step. The next step is to estimate the effector that caused the changes in loop gain. A de-correlating excitation is injected into the null space of the effecters through the control allocation. This allows the individual control derivatives to be estimated. In addition, the adverse effects of nonlinearities on the identification performance of the control and stability derivatives, are investigated. Results are presented for a tailless fighter aircraft simulation. C1 USAF, Inst Technol, Dept Elect & Comp Engn, AFIT,ENG, Wright Patterson AFB, OH 45433 USA. RP Pachter, M (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, AFIT,ENG, Wright Patterson AFB, OH 45433 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 510 EP 520 PG 11 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000052 ER PT B AU Naidu, DS Buffington, JL Banda, SS AF Naidu, DS Buffington, JL Banda, SS GP AIAA AIAA TI Resurrection in hypersonics: Why, what and when SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB The US Air Force has recognized "hypersonics" as one of the key technologies to be developed for the 21(st) century and that hypersonic technology and ramjet/SCRamjet propulsion offer potentially large increases in speed, altitude and range with flexible recall, en route redirection and return to base for military operations such as interceptor, reconnaissance and orbital transport. In pursuing this direction, the Air Force Research Laboratory at Wright-Patterson Air Force Base, OH, is "heading" towards research on space and related activities. The focus is on guidance and control (G&C) strategies for hypersonic vehicles. In this paper, we focus Why there is resurrection in hypersonics, What are the issues and challenges in G&C for hypersonic vehicles and finally When this program is expected to have an operational capability. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 41 TC 0 Z9 0 U1 0 U2 2 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 563 EP 573 PG 11 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000058 ER PT B AU Cloutier, JR Stansbery, DT AF Cloutier, JR Stansbery, DT GP AIAA AIAA TI All-aspect acceleration-limited homing guidance SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB A new guidance law is developed for agile missiles to provide the capability to intercept targets in severe off boresight scenarios and in rear hemisphere engagements. By accounting for the relative kinematics between the missile body and its velocity vector, the guidance law is able to effectively govern the sluing of the missile velocity vector toward the line-of-sight (LOS) vector through the issuance of body acceleration commands. Due to the embedding of a hard bound on missile acceleration within the modeled kinematics, the guidance law only commands acceleration magnitudes that are achievable by the vehicle, thereby eliminating the risk of actuator saturation. The state-dependent Riccati equation (SDRE) technique is used to solve the nonlinear guidance law formulation. The new guidance law is used until the closing velocity is positive and the LOS rates are decreasing; a traditional homing guidance law can then be initiated and used for the remainder of the intercept. C1 USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. RP Cloutier, JR (reprint author), USAF, Res Lab, Munit Directorate, 101 W Eglin BLvd,Ste 341, Eglin AFB, FL 32542 USA. NR 12 TC 2 Z9 2 U1 0 U2 1 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 633 EP 639 PG 7 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000066 ER PT B AU Schumacher, C AF Schumacher, C GP AIAA AIAA TI Adaptive flight control using dynamic inversion and neural networks SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut ID AIRCRAFT AB This paper presents an application of dynamic inversion control with adaptive neural networks to a tailless fighter aircraft. This technique has, in the past, typically been implemented using proportional-derivative desired dynamics, and has recently been extended to a special case of proportional-integral desired dynamics using implicit model-following. This paper presents a method to incorporate adaptive neural networks into an explicit model-following dynamic inversion controller with arbitrary PI desired dynamics. An adaptive controller designed with this method is compared with an adaptive dynamic inversion controller using proportional-derivative desired dynamics and a baseline dynamic inversion controller with PI desired dynamics and no adaptation. The controllers are evaluated by simulation on a six degree-of-freedom tailless fighter simulation during a simultaneous longitudinal and lateral maneuver. The PI dynamic inversion controller with adaptation outperforms the other two controllers and achieves the tightest tracking of commanded maneuvers both during normal flight and with a failed control surface. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Schumacher, C (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 811 EP 819 PG 9 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000084 ER PT B AU Naidu, DS Banda, SS Buffington, JL AF Naidu, DS Banda, SS Buffington, JL GP AIAA AIAA TI Optimal control of singularly perturbed systems with inequality constraints SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB The optimal control problem of a singularly perturbed nonlinear system with state and control inequality constraints is investigated. First, the problem is formulated in a more general and different form and the various characteristic features of the analysis are discussed. Next, after reviewing briefly the previous methods, two more methods are proposed. One is based on the idea of a reformulation of the optimal control problem with constraints. This method which reformulates the constrained optimal control problem as an constrained problem using special derivative multipliers, is expected to provide more efficient and accurate numerical solutions to constrained optimal control problems. The second method is based on neighboring optimal control with constraints. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Naidu, DS (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 883 EP 891 PG 9 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000091 ER PT B AU Doman, DB AF Doman, DB GP AIAA AIAA TI On the feasibility of piloting hypersonic vehicles: A pilot modeling approach SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB The feasibility of piloting: hypersonic vehicles (HSVs) has often been debated. Metrics obtained from optimal-control-based pilot modeling techniques are proposed that allow comparisons between manually and automatically controlled HSVs to be made. Such methods can be used in preliminary design studies to determine the level of augmentation and actuator bandwidth required for pilots to successfully execute mission task elements. The breakdown of the assumption that pitch rate command systems constitute optimal longitudinal aircraft dynamics is illustrated by considering a flight-path tracking task carried out with a typical HSV controlled element that has a large flight path lag. Normal acceleration command systems are designed using: a control-rate linear quadratic Gaussian (LQG) technique that synthesizes dynamic compensators that are optimal subject to actuator bandwidth constraints. The modified optimal control model (MOCM) of human response is used to predict man/HSV performance for flight-path tracking tasks. The technique is illustrated using an elementary example consisting of a flight-path tracking task with an unusually large flight-path lag that is characteristic of a HSV. The performance of manually and automatically controlled systems are compared to illustrate how such information can be used to systematically evaluate the benefits and disadvantages of manual control. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Doman, DB (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 892 EP 900 PG 9 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000092 ER PT B AU Proud, AW Pachter, M D'Azzo, JJ AF Proud, AW Pachter, M D'Azzo, JJ GP AIAA AIAA TI Close formation flight control SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB In this paper the close formation flight control problem is addressed. The formation consists of a lead and wing aircraft, where the wing flies in close formation with the lead, such that the lead's vortices produce aerodynamic coupling effects, and a reduction in the formation's drag is achieved. A controller, i.e., a formation-hold autopilot for the wing aircraft, is designed such that the formation's geometry is maintained in the face of lead aircraft maneuvers. In the formation flight control system, the wing and lead aircraft dynamics are coupled due to kinematic effects, and, in the case of close formations, additional aerodynamic coupling effects are introduced. In the paper these additional aerodynamic coupling effects are properly modeled. The most significant aerodynamic coupling effect introduced by close formation flight entails the coupling of the lateral/directional channel into the altitude-hold autopilot channel. It is shown that formation hold autopilots designed ignoring the aerodynamic coupling effects yield satisfactory performance in close formation flight. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Proud, AW (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 12 TC 2 Z9 5 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 1231 EP 1246 PG 16 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000126 ER PT B AU Davis, CJ Heise, SA AF Davis, CJ Heise, SA GP AIAA AIAA TI Solving an inverse control problem using predictive methods with application to an aircraft accident SO AIAA GUIDANCE, NAVIGATION, AND CONTROL CONFERENCE, VOLS 1-3: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Guidance, Navigation, and Control Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB Recently, much interest has been focused in the area of reconstructing aircraft accidents based on the information available in the Cockpit Voice Recorder (CVR) and the Flight Data Recorder (FDR) post-crash. The CVR can provide audible clues of the accident's cause such as stall warnings, engine noise, landing gear extension/retraction, etc. Aircraft investigators use this information in an attempt to determine the cause of the accident - be it a control surface failure or other cause. Previous researchers have utilized this information and an assumed set of control inputs to reproduce the outputs that were provided from the FDR in an aircraft accident. Still others have used a neural network simulator and "Virtual" FDR to reconstruct the control surface deflections. In this paper, predictive methods are used, with the actual FDR data as the setpoints, in an attempt to determine the control inputs which produced the outputs provided by the FDR. Using this method, it is possible to develop a control sequence which produces analytic results consistent with the findings of previous investigators. C1 USAF, Wright Patterson AFB, OH 45433 USA. RP Davis, CJ (reprint author), USAF, Wright Patterson AFB, OH 45433 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-299-6 PY 1999 BP 1364 EP 1370 PG 7 WC Engineering, Aerospace SC Engineering GA BP87S UT WOS:000086465000138 ER PT B AU Zipfel, PH O'Grady, T AF Zipfel, PH O'Grady, T GP AIAA AIAA TI Missile model fidelity and integration for air combat simulators SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB Air combat simulators with their missiles are gaining increased importance as virtual prototyping is becoming a reality. After reviewing the dynamics of close-in air-to-air combat, we compare the fidelity of five and six degrees-of-freedom models of a generic short range missile. The 5 DoF model, adjusted for 6 DoF effects, is adequate for most situations. To speed up the insertion of missile prototypes into manned simulators, an automated conversion process from batch to real-time code is currently being tested. C1 USAF, Res Lab, Eglin AFB, FL 32542 USA. RP Zipfel, PH (reprint author), USAF, Res Lab, Eglin AFB, FL 32542 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 49 EP 58 PG 6 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300006 ER PT B AU Martin, EA Brett, BE Hoagland, DG AF Martin, EA Brett, BE Hoagland, DG GP AIAA AIAA TI Tools for including realistic representations of operator performance in DoD constructive simulations SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB Military weapon systems are normally built to satisfy a set of requirements levied by the warfighter. All these weapon systems are manned in some sense, yet tools for quantifying the effectiveness with which a crewstation must support operator performance are lacking. Analysts and decision-makers need a means to readily model and understand the effects of human performance on total weapon system effectiveness when translating operational requirements into system requirements. This paper discusses the research and demonstration activities being conducted by the Combat Automation Requirements Testbed (CART) Program within the Air Force Research Laboratory / Human Effectiveness Directorate. CART will demonstrate how human-in-the-loop and constructive operator models and data can be integrated with Simulation-Based Acquisition activities for the purpose of defining crewstation requirements. Utilizing the Army's IMPRINT human-performance modeling environment, CART will provide High Level Architecture (HLA) interfaces that enable human-performance models to interact with constructive models of systems. A second extension will incorporate the ability to represent the goal-oriented nature of human performance. Modelers and analysts will be able to define operator goal states and priorities that dynamically drive task network models based on changing states and events in simulated military environments. C1 USAF, Res Lab, Human Effictiveness Directorate, Crew Syst Interface Div, Wright Patterson AFB, OH 45433 USA. RP Martin, EA (reprint author), USAF, Res Lab, Human Effictiveness Directorate, Crew Syst Interface Div, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 59 EP 67 PG 3 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300007 ER PT B AU Subr, RC AF Subr, RC GP AIAA AIAA TI Virtual battle-space management system: A real-time simulation development and management tool SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB With simulation environments becoming more complex, it is important to have flexible tools to help visualize the simulation. The Virtual Battle-Space Management System (VBMS) is one such tool. The VBMS software represents a landmark advancement in the generation of high-performance, state-of-the-art virtual/synthetic tools. It was designed to aid in the development, operation, and analysis of real-time mission level simulations. By using several unique viewing methods, VBMS can be used for validation, monitoring, out-the-window visualization for pilot combat stations, subject debriefing, and analysis. Several advanced programming interfaces (API) provide users with a flexible and cost effective tool for research, acquisition, test and evaluation, and training tasks. The C++ design is built around the Silicon Graphics Performer API, which adds a flexible cost effective graphics library for fast prototyping with optimized performance and allows VBMS to operate on the full line of Silicon Graphics computers. This paper will discuss the development, operation, and design of the VBMS Software. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Subr, RC (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 193 EP 200 PG 4 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300020 ER PT B AU Rodgers, SM Hellmann, GK Menke, TE Mittlesteadt, DR Zeh, JM Richart, DK AF Rodgers, SM Hellmann, GK Menke, TE Mittlesteadt, DR Zeh, JM Richart, DK GP AIAA AIAA TI The "new" air combat modeling, simulation, and analysis federation at Wright-Patterson AFB, OH SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB Sweeping changes throughout the Department of Defense to improve efficiencies in acquisition processes have led to the creation of the simulation and analysis facility, or SIMAF, at Wright-Patterson AFB (WPAFB), OH. SIMAF is owned and operated by the Aeronautical Systems Center (ASC) in a substantial teaming partnership with the Air Force Research Laboratory (AFRL). The facility is staffed with a new modeling, simulation, and analysis federation. The federation has been formed through partnerships with engineering, analysis, and simulation offices at WPAFB. With SIMAF, this federation is conducting simulation and analysis for system and requirements trades in a way that is prototypical of the Simulation Based Acquisition vision. SIMAF fulfills the need for a facility appropriate for conducting highly classified simulations. This capability enables collaborative teams of USAF decision-makers, warfighters, and analysts to better and more quickly evaluate and develop advanced concepts and technologies for military applications. The federation's innovations include a more rigorous analytical approach to modeling and simulation using state-of-the-art distributed computing capabilities. The analysis approach capitalizes upon the complementary strengths of constructive and virtual simulation methodologies. SIMAF provides cutting-edge visualization capabilities, computing power, and air-to-air and air-to-ground combat simulations. C1 Aeronaut Syst Ctr, Air Combat SPO, Wright Patterson AFB, OH 45433 USA. RP Rodgers, SM (reprint author), Aeronaut Syst Ctr, Air Combat SPO, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 238 EP 246 PG 3 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300026 ER PT B AU Myatt, JH Blake, WB AF Myatt, JH Blake, WB GP AIAA AIAA TI Aerodynamic database issues for modeling close formation flight SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB Experimental data for the trail aircraft in a two-ship formation are presented. Aerodynamic force and moment data show that the drag of the trail aircraft is reduced for a given lift when the aircraft are properly positioned. The data are analyzed from the perspective of simplifications to the aerodynamic database needed for adequate simulation of close formation flight. C1 USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. RP Myatt, JH (reprint author), USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 317 EP 327 PG 5 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300035 ER PT B AU Stadler, BK AF Stadler, BK GP AIAA AIAA TI Recent improvements to the Large Amplitude Multi-Mode Aerospace Research Simulator (LAMARS) SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB The Large Amplitude Multi-Mode Aerospace Research Simulator(LAMARS) has been the Air Force Research Laboratory Air Vehicle Directorate's primary handling qualities simulator since the mid 70's. Built by Northrop Corporation for the USAF Flight Dynamics Laboratory, this venerable simulator has gone through a variety of facelifts and improvements that have increased its utility beyond just flying qualities experiments. During the late eighties and early nineties, work was completed on improving the LAMARS visual system which entailed repairs and resurfacing of the spherical projection screen. In addition, new color projectors have been installed to provide increased out-the-window coverage and improved image quality which, when coupled with the motion system, provides an excellent emulation of the flight environment. In order to keep current with advanced weapon system programs, cockpit equipment upgrades have included raster multi-function displays, sound system, and installation of a magnetic head tracker system for helmet mounted display studies. Other visual system upgrades include the incorporation of two laser target projectors for drawing calligraphic images as well as a new low-resolution projector to replace the original sky-earth projector. These upgrades became critical along with better documentation of the motion system as part of in-house experiments in the area of pilot induced oscillations (PIO). C1 USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. RP Stadler, BK (reprint author), USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 362 EP 371 PG 4 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300040 ER PT B AU McKeehen, PD AF McKeehen, PD GP AIAA AIAA TI Hypervelocity vehicle modeling and simulation using GENESIS SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB This paper discusses the use of GENeral Environment for the Simulation of Integrated Systems(GENESiS) in the modeling and non-realtime 6 DOF simulation of a Two Stage To Orbit (TSTO) hypervelocity vehicle which uses a combination of scramjet and rocket propulsion modes. The vehicle configuration is the highly swept double-delta planform defined in the 1991 Northrop-Grumman Modem Aerospace Vehicles Robust H-Infinity Control (MAVRIC) contract with the USAF. The discussion topics include: an overview of the Fortran 77-based GENESIS software's structure and basic functionality; the simulation's aerodynamic, propulsion, and structural models; linear model generation and control law design issues. Examples of simulation output time-histories for simple maneuvers are shown. C1 USAF, Res Lab, VAAD, Wright Patterson AFB, OH 45433 USA. RP McKeehen, PD (reprint author), USAF, Res Lab, VAAD, Wright Patterson AFB, OH 45433 USA. NR 13 TC 0 Z9 0 U1 0 U2 1 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 442 EP 451 PG 6 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300049 ER PT B AU Nalepka, J Caudill, D Mutschler, L Buell, C Garcia, L O'Quinn, D AF Nalepka, J Caudill, D Mutschler, L Buell, C Garcia, L O'Quinn, D GP AIAA AIAA TI Challenges in integrating Commercial Off-The-Shelf (COTS) software into a real-time simulation environment SO AIAA MODELING AND SIMULATION TECHNOLOGIES CONFERENCE: A COLLECTION OF TECHNICAL PAPERS LA English DT Proceedings Paper CT AIAA Modeling and Simulation Technologies Conference CY AUG 09-11, 1999 CL PORTLAND, OR SP Amer Inst Aeronaut & Astronaut AB Simulation Based Acquisition (SBA) is becoming a more prevalent method for planning, designing, integrating, and testing advanced weapon systems or other products. The end result of this process, in theory, is a product that is produced faster, cheaper and more reliably than its predecessors. It is critical that the environment being simulated in the SEA process accurately model the conditions under which the SEA product will be operating. Consequently, program managers must make a decision as to what types of components are necessary for the simulation as well as how these types of components wilt be developed. Commercial Off-the-Shelf (COTS) software products are being used to fill those simulation needs, maintain simulation fidelity, and to help meet schedule and cost constraints. An ongoing simulation program being conducted at the Air Force Research Laboratory (AFRL) simulation facility located at Wright-Patterson Air Force Base successfully integrated COTS software products into a real-time, simulation architecture. During the simulation development process, several hardware and software challenges were encountered that made integrating the COTS software products within the simulation architecture very difficult. Once these challenges were overcome, the end result was a very realistic and cost effective simulation that will be used to assess the feasibility of technologies being slated for a future tactical aircraft. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Nalepka, J (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUTICS & ASTRONAUTICS PI RESTON PA 1801 ALEXANDER BELL DR, STE 500, RESTON, VA 20191-4344 USA BN 1-56347-301-1 PY 1999 BP 572 EP 580 PG 3 WC Engineering, Aerospace; Computer Science, Software Engineering SC Engineering; Computer Science GA BP86K UT WOS:000086446300063 ER PT S AU Senft, DC Fox, MJ Hamilton, CM Richter, DA Higdon, NS Kelly, BT Babnick, RD Pierrottet, DF AF Senft, DC Fox, MJ Hamilton, CM Richter, DA Higdon, NS Kelly, BT Babnick, RD Pierrottet, DF BE Leonelli, J Althouse, ML TI Chemical detection results from ground testing of an airborne CO2 differential absorption lidar system SO AIR MONITORING AND DETECTION OF CHEMICAL AND BIOLOGICAL AGENTS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Air Monitoring and Detection of Chemical and Biological Agents II CY SEP 21-22, 1999 CL BOSTON, MA SP SPIE, Air & Waste Management Assoc, Opt Sci Div DE laser remote sensing; CO2 DIAL; lidar chemical detection; heterodyne DIAL AB The Air Force Research Laboratory (AFRL) Active Remote Sensing Blanch has developed the Laser Airborne Remote Sensing (LARS) system for long standoff range chemical detection using the differential absorption lidar (DIAL) technique. The system is based on a high-power CO2 laser which uses either the (CO2)-C-12-O-16 or the (CO2)-C-13-O-16 carbon dioxide isotopes as the lasing medium, and has output energies of up to 5 J on the stronger laser transitions. The lidar system is mounted on a flight-qualified optical breadboard designed for installation in the AFRL Argus C-135E optical testbed aircraft. This paper will present chemical detection results and issues arising from ground tests of the system performed from September to December 1998. Recent advances in implementing a frequency-agile heterodyne receiver to further increase the standoff range of the DIAL system will also be presented. C1 USAF, Res Lab, DEBF, Kirtland AFB, NM 87117 USA. RP Fox, MJ (reprint author), USAF, Res Lab, DEBF, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. 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 0-8194-3448-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3855 BP 144 EP 156 DI 10.1117/12.371273 PG 13 WC Chemistry, Analytical; Environmental Sciences; Remote Sensing; Optics SC Chemistry; Environmental Sciences & Ecology; Remote Sensing; Optics GA BP35E UT WOS:000084810600016 ER PT S AU Hugo, RJ Nowlin, SR Eaton, FD Bishop, KP McCrae, KA AF Hugo, RJ Nowlin, SR Eaton, FD Bishop, KP McCrae, KA BE Steiner, TD Merritt, PH TI Hot-wire calibration in a non-isothermal incompressible pressure variant flow SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE hot-wire anemometry; constant-current anemometry; non-isothermal; pressure variant; calibration ID COLD-WIRE; TEMPERATURE AB The calibration procedure for a hot-wire anemometer system operating in a non-isothermal, pressure-variant flow field is presented. Sensing of atmospheric velocity and temperature fluctuations from an altitude-variant platform (like a kite or tethered balloon, for instance) using hot-wire anemometry equipment operating in both constant-temperature and constant-current modes requires calibration for velocity, temperature, and atmospheric pressure variations. Calibration tests to provide the range of velocity, temperature and pressure variations anticipated during Air Force Research Lab, Directed Energy Directorate-sponsored kite/tethered-balloon experiments were conducted and the results of these tests presented. The calibration tests were performed by placing the kite/tethered-balloon sensor package on a vehicle (van) and driving from Kirtland AFB, NM (elevation 5400 ft) to the top of Sandia Crest, a 10678 ft mountain range to the east of Albuquerque, NM. By varying the velocity of the van and conducting the tests at different times of the day, variations in velocity, temperature and pressure within the range of those encountered during the kite/tethered-balloon experiments were obtained. The method of collapsing the calibration data is presented. Problems associated with collecting hot-wire anemometry data in a non-laboratory environment are discussed. Example data sets of temperature and velocity collected during the kite/tethered-balloon experiments are presented. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Nowlin, SR (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 21 TC 6 Z9 6 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 11 EP 22 DI 10.1117/12.356955 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800002 ER PT S AU Eaton, FD Balsley, BB Bishop, K Frehlich, RD Hugo, R Jensen, M McCrae, K AF Eaton, FD Balsley, BB Bishop, K Frehlich, RD Hugo, R Jensen, M McCrae, K BE Steiner, TD Merritt, PH TI In situ turbulence measurements over a desert basin using a kite/tethered-blimp platform SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE refractive index structure parameter; eddy dissipation rate; planetary boundary layer; kite/blimp platform; radar ID SANDS-MISSILE-RANGE; NEW-MEXICO; RADAR OBSERVATIONS; DISSIPATION RATES; KITES; ATMOSPHERE AB Results of the (temperature) refractive index structure parameter (C-T(2)), C-n(2), and the eddy dissipation rate, epsilon, derived from the velocity structure parameter, C-v(2), are presented from high speed fluctuation measurements taken using a kite/tethered-blimp platform in the Tularosa Basin at White Sands Missile Range, NM during the spring of 1998. Comparisons of different sensors (fine wire probes and pitot tubes) measuring the same parameter are displayed and discussed. Salient features of the sensors and the kite and blimp platforms are outlined.. Long term measurements of high speed fluctuations of temperature and velocity are shown and intermittency of turbulence is discussed. The nature and statistics of turbulence inside, outside, and at the boundary of a turbulent layer are also shown and interpreted. Observations in the entrainment zone at the top of the planetary boundary layer are shown and similarities of characteristics found in the tropopause region with these boundary layer features is discussed. The diurnal variation of turbulence is presented with particular emphasis on the transition period from the end of daytime convection to development of the stable nocturnal boundary layer. Results are displayed as profiles and histograms of C-n(2) and epsilon for daytime, near sunset, and nighttime conditions. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Eaton, FD (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 21 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 23 EP 32 DI 10.1117/12.356966 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800003 ER PT S AU Roadcap, JR McNicholl, PJ Laird, MH Swirbalus, RA AF Roadcap, JR McNicholl, PJ Laird, MH Swirbalus, RA BE Steiner, TD Merritt, PH TI CO2 Doppler lidar measurement of wind velocity and relative backscatter associated with the nocturnal boundary layer SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE lidar; heterodyne; VAD; nocturnal boundary layer AB Heterodyne CO2 Doppler lidar measurements of horizontal wind velocity from the surface to 11,000 feet AGL using the Velocity Azimuth Display (VAD) method were made at Holloman AFB, New Mexico from the end of July through mid-August 1998. These data were entered real-time into the Space Maneuver Vehicle Descent Analysis Program to make night performance predictions needed for test decisions. Daily measurements encompassed the early morning time period associated with the stably-stratifed nocturnal boundary layer (NJBL). Measurement periods were characterized by growth and decay of wind maxima or jets at different altitudes. Strong vertical shears were often observed in conjunction with these wind maxima. Relative backscatter profiles at the lowest altitudes exhibited periodic oscillations on most mornings. The observed NBL wind profiles were poorly represented by the Ekman model. C1 USAF, Res Lab, Space Vehicle Directorate, Hanscom AFB, MA 01731 USA. RP Roadcap, JR (reprint author), USAF, Res Lab, Space Vehicle Directorate, Hanscom AFB, MA 01731 USA. NR 5 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 33 EP 41 DI 10.1117/12.356971 PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800004 ER PT S AU Grover, DM Eaton, FD Berkopec, T AF Grover, DM Eaton, FD Berkopec, T BE Steiner, TD Merritt, PH TI ABLACT atmospheric metrology SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE atmospheric turbulence; scintillation; wind scintillometer; transverse coherence length; isoplanatic angle AB We comment on the new atmospheric metrology experiments conducted in support of ABLACT. We will present the results from a wind-scintillometer experiment and show the most recent transverse coherence length (r(o)) and isoplanatic angle (theta(o)) data from a new Atmospheric Turbulence Measurement and Observation System (ATMOS). The results from the wind scintillometer are inconclusive, and we suggest possible explanations and improvements. The ATMOS data provides a promising short-term characterization of North Oscura Peak. In addition, we address the ability to predict r(o) from the local wind speeds. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Grover, DM (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 42 EP 53 DI 10.1117/12.356976 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800005 ER PT S AU Hugo, RJ Nowlin, SR Hahn, IL Bishop, KP McCrae, KA AF Hugo, RJ Nowlin, SR Hahn, IL Bishop, KP McCrae, KA BE Steiner, TD Merritt, PH TI Aircraft based in-situ calibration of a hot-wire anemometer in a compressible flow SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE hot-wire anemometry; constant-current anemometry; compressible; calibration; aircraft measurements AB High-bandwidth measurements of atmospheric velocity and temperature fluctuations in the high troposphere / low stratosphere using aircraft-based hot-wire anemometers requires calibration. An in-situ calibration characterizing wire sensitivity at high subsonic Mach numbers and relatively low temperatures and pressures was performed. Custom designed constant-temperature and constant-current anemometer equipment has been used for these atmospheric measurements. Two sets of calibration experiments are described, one in a controlled laboratory environment where the Mach number and temperature were varied (although not independently) and the other on board a C-135E aircraft. The aircraft tests were conducted by varying the flight Mach number at different pressure altitudes while flying into an upper-level low pressure area, achieving variability in velocity, temperature, and pressure. Results obtained indicate increased sensitivity to velocity while operating the wire at a low overheat ratio (approximate to 0.20). The calibration data was fit to a form of King's law which was found to work well for in-situ calibrations. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Nowlin, SR (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 34 TC 1 Z9 1 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 54 EP 67 DI 10.1117/12.356979 PG 14 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800006 ER PT S AU Nowlin, S Hahn, I Hugo, R Bishop, K AF Nowlin, S Hahn, I Hugo, R Bishop, K BE Steiner, TD Merritt, PH TI Concurrent aerial and ground-based optical turbulence measurements along a long, elevated path SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE airborne measurements; anemometer; atmospheric turbulence; optical turbulence; refractive index structure parameter; scintillation; turbulence AB We report concurrent ground-based scintillometer / airborne constant-current anemometer (CCA) measurements made along a 51.4 km-long slant path between Salinas and North Oscura peaks, New Mexico. Simultaneous path-averaged refractive index structure parameter (C-n(2)) measurements from the CCA and the scintillometer show good agreement, with deviations apparently due to localized effects of underlying topography and meteorology. Statistics from both data sets are presented in the form of histograms and cumulative distribution functions. CCA C-n(2) point measurements are compared to underlying surface topography. We discuss possible effects of instrumentation anomalies, analysis methods, and atmospheric velocity fluctuation levels. We present conclusions and make recommendations for future similar experimental efforts. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Nowlin, S (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 11 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 68 EP 79 DI 10.1117/12.356980 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800007 ER PT S AU Eaton, FD Nastrom, GD Hansen, AR Brown, W AF Eaton, FD Nastrom, GD Hansen, AR Brown, W BE Steiner, TD Merritt, PH TI Variability of slant-path turbulence parameters and inner scale effects SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE refractive index structure parameter; transverse coherence length; isoplanatic angle; Rytov variance; turbulence; radar; atmospheric propagation ID SANDS-MISSILE-RANGE; VHF RADAR OBSERVATIONS; WHITE-SANDS; NEW-MEXICO AB six-year data set of refractive index structure parameter ( C-n(2)) results from VHF radar observations at White Sands Missile Range, NM is used to calculate slant path values of the transverse coherence length ( r(o)), the isoplanatic angle (theta(o)), and the Rytov variance (sigma(R)(2)). The calculations were for a spherical wave condition, a wavelength of 1 mu m, four different elevation angles (3, 10, 30, and 60 deg), two path lengths (50 km and 150 km), and a platform, such as an aircraft, at 12.5 km MSL. Over 281,000 radar-derived ( C-n(2)) profiles sampled at three minute intervals with 150-m height resolution were used for the calculations. The approach, an "onion skin" model, assumes horizontal stationarity over each entire propagation path and is consistent with Taylor's hypothesis. Refractivity turbulent effects are greatly reduced as the elevation angle increases, a pronounced seasonal effect is seen consistent with climatological variables and gravity wave activity, and interactions of enhanced turbulence in the tropopause region is evaluated. An evaluation of inner scale on the calculations is discussed. Results of a two region model understood in terms of upward propagating gravity waves that are launched by strong winds over complex terrain are shown. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Eaton, FD (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 80 EP 88 DI 10.1117/12.356981 PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800008 ER PT S AU Ryan, PT Wynia, JL Spillar, EJ Delarue, IA Fugate, RQ AF Ryan, PT Wynia, JL Spillar, EJ Delarue, IA Fugate, RQ BE Steiner, TD Merritt, PH TI Stellar scintillation in the near-IR SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE atmospheric turbulence; scintillation AB dThe Starfire Optical Range (SOR) has measured stellar scintillation at 0.9 to 1.7 microns over a wide range of elevation angles. The telescope pupil was imaged onto a mask with four circular apertures of scaled diameters 0.1, 0.2, 0.75 and 1.5 m. These smaller pupils were then re-imaged onto InGaAs photodiodes operating at 10 kHz. The entire 3.5 m pupil was also imaged onto a fifth photodiode. Since all five signals were recorded simultaneously, the influence of aperture diameter on scintillation statistics can be readily seen. The detectors were located at pupil planes; no fluctuations due to atmospheric tilt were measured. Comparisons of power spectral densities, signal variances and other fluctuation statistics have been made as functions of the aperture diameter and elevation angle. Experimental results and theoretical expectations reveal widespread agreement. Within experimental error, log-normal statistics are followed. High spatial frequency content increased with elevation angle. Aperture averaging of scintillation variance followed a 7/6(th) dependence. Increasing the aperture dimensions had an even larger effect on the number of fluctuations below a given threshold. Scintillation in the near-IR has been shown to produce consistent results with previous studies performed at visible wavelengths. C1 USAF, Res Lab, Directed Energy Directorate, Starfire Opt Range, Kirtland AFB, NM 87117 USA. RP Ryan, PT (reprint author), USAF, Res Lab, Directed Energy Directorate, Starfire Opt Range, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 6 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 89 EP 94 DI 10.1117/12.356982 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800009 ER PT S AU Nowlin, S Hahn, I Hugo, R Bishop, K AF Nowlin, S Hahn, I Hugo, R Bishop, K BE Steiner, TD Merritt, PH TI Qualitative comparison of concurrent vertical optical turbulence profiles from an aircraft and balloons over White Sands Missile Range SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE airborne measurements; anemometer; atmospheric turbulence; balloon; optical turbulence; refractive index structure parameter; thermosondes; turbulence measurement AB We report simultaneous balloon-borne thermosonde / airborne constant-current anemometer measurements made over a portion of White Sands Missile Range, New Mexico. For the first time, vertical profiles of the refractive index structure parameter (C-n(2)) data generated from shallow slant aircraft night paths are compared to the balloons' vertical C-n(2) distributions. We discuss possible adverse effects of meteorology and atmospheric velocity fluctuations. We present conclusions and make recommendations for future similar experimental efforts. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Nowlin, S (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 12 TC 0 Z9 0 U1 1 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 95 EP 102 DI 10.1117/12.356948 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800010 ER PT S AU Riker, J Roark, J Stogsdill, S DeShetler, B Brunson, D AF Riker, J Roark, J Stogsdill, S DeShetler, B Brunson, D BE Steiner, TD Merritt, PH TI The Absolute Radiometric Code (ARC) SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE radiometry; optical cross section; Matlab AB The Absolute Radiometric Code (ARC) is a collection of Matlab functions tied together under a Matlab Graphical User Interface (GUI). ARC was developed as part of the Satellite Imaging Experiment (SIE) conducted by the Air Force Research Laboratory (AFRL) at Kirtland AFB, in order to get fast estimates of the Optical Cross Sections (OCS) of various satellites. ARC uses multiple star measurements to calculate the atmospheric and optical transmission of the system. The transmissions are then used to compute the optical cross section of an object. Generally, the optical transmission of a sensor system can be characterized quite well, so it serves as a sanity check on all ARC results. The atmospheric transmission changes considerably from night to night and even from hour to hour on the same night. ARC uses a collection of calibration stars at various elevation angles to determine the atmospheric transmission through the viewing times. The star calibration is generally taken several times during the experiment period. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Riker, J (reprint author), USAF, Res Lab, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 9 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 121 EP 131 DI 10.1117/12.356950 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800013 ER PT S AU Riker, J Roark, J Stogsdill, S DeShelter, B Brunson, D AF Riker, J Roark, J Stogsdill, S DeShelter, B Brunson, D BE Steiner, TD Merritt, PH TI The Absolute Radiometric Code (ARC) test results SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE radiometry; optical cross section; matlab; test results AB In this paper, we present some results of absolute radiometry and optical cross-section calculations from the Absolute Radiometric Code (ARC). ARC provides near real-time estimates of absolute radiometry and optical cross sections of objects. The data were taken at the Starfire Optical Range (SOR) on Kirtland AFB between March 1997 and December 1998 as part of the Satellite Imaging Experiment (SIE) conducted by the Air Force Research laboratory (AFRL). C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Riker, J (reprint author), USAF, Res Lab, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 3 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 132 EP 141 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800014 ER PT S AU Brennan, EJ Brunson, D AF Brennan, EJ Brunson, D BE Steiner, TD Merritt, PH TI Application of SOQ in the analysis of high power optical trains SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE AB Optical systems which transmit high power density optical radiation present real design and implementation challenges. Sophisticated multi-disciplinary methods have been developed to support the design and analysis of the interaction of the optical radiation field and the transmissive and reflective optics which the field interacts with. The primary effect which results are distributed thermal deformation of the optical surfaces resulting in undesirable aberrations, loss of Strehl and beam "quality". Modern optical systems involve the use of adaptive optical systems which mitigate the effect of these aberrations within their spatial and temporal correction bandwidths. The authors have been involved in a study, which addresses the closed loop correction of thermally induced beam train aberrations using computational numerical models to describe the wavefront effects. This paper reports on the analysis methods used and describes some preliminary results. C1 USAF, Airborne Laser Syst Program Off, Washington, DC 20330 USA. RP Brennan, EJ (reprint author), USAF, Airborne Laser Syst Program Off, Washington, DC 20330 USA. NR 1 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 159 EP 169 DI 10.1117/12.356953 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800017 ER PT S AU Steiner, TD Butts, RR AF Steiner, TD Butts, RR BE Steiner, TD Merritt, PH TI The Airborne Laser Advanced Concepts Testbed SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE AB The Airborne Laser Advanced Concepts Testbed (ABL ACT) is a low power beam control test facility located at the northern end of White Sands Missile Range atop North Oscura Peak. The purpose of ABL ACT is to explore concepts for laser propagation under high scintillation conditions. This paper gives an updated overview of the facility, reviews data collected to date, and details future plans. C1 USAF, Res Lab, Directed Energy Directorate, Airborne Laser Technol Branch, Kirtland AFB, NM 87117 USA. RP Steiner, TD (reprint author), USAF, Res Lab, Directed Energy Directorate, Airborne Laser Technol Branch, Kirtland AFB, NM 87117 USA. NR 4 TC 3 Z9 3 U1 1 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 180 EP 186 DI 10.1117/12.356956 PG 7 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800019 ER PT S AU Browning, WM Olson, DS Keenan, DE AF Browning, WM Olson, DS Keenan, DE BE Steiner, TD Merritt, PH TI High Altitude Balloon Experiment SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE AB The mission of the High Altitude Balloon Experiment (HABE) is to resolve critical acquisition, tracking, and pointing (ATP) and fire control issues, validate enabling technologies, simulations, and models, and acquire supporting data for future space-based lasers (SBL) experiments. HABE is integrating components from existing technologies into a payload that can autonomously acquire, track, and point a law power laser at a ballistic missile in its boost phase of flight. For its primary mission the payload will be flown multiple times to an altitude of 85,000 feet above the White Sands Missile Range (WSMR). From the near-space environment of the balloon flight, HABE will demonstrate the ATP functions required for a space-based laser in a ballistic missile defense role. The HABE platform includes coarse and fine gimbal pointing, infrared and visible passive tracking, active fine tracking, internal auto-alignment and boresighting, and precision line-of-sight (LOS) stabilization functions. This paper presents an overview and status of the HABE program. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Browning, WM (reprint author), USAF, Res Lab, Space Vehicles Directorate, 3550 Aberdeen Ave SE,Bldg 472, Kirtland AFB, NM 87117 USA. NR 1 TC 0 Z9 0 U1 2 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 187 EP 195 DI 10.1117/12.356957 PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800020 ER PT S AU Tellez, JA Robertson, L Tipton, C Jordan, D Ratee, K Van Berg, C AF Tellez, JA Robertson, L Tipton, C Jordan, D Ratee, K Van Berg, C BE Steiner, TD Merritt, PH TI ABL-ACT ATP system buildup at the NuSord facility SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE tracking; gimbal control; ABL-ACT; mode logic; dome control AB Before fine tracking algorithms can be evaluated for performance at the ABL-ACT facility at North Oscura Peak, the image needs to get onto the fine track sensor. This requires interaction between the gimbal controller, course tracker, and the fine tracker. In order to develop this hardware for North Oscura Peak, and to meet the proposed schedule, a local facility was required. NuSord was developed for this purpose. In addition to supporting the buidup, NuSord will assist in the integration of future hardware and software systems that would eventually end up at NOP. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Tellez, JA (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 2 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 258 EP 265 DI 10.1117/12.356964 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800027 ER PT S AU Tellez, JA Robertson, L Tipton, C Jordan, D Ratte, K Van Berg, C AF Tellez, JA Robertson, L Tipton, C Jordan, D Ratte, K Van Berg, C BE Steiner, TD Merritt, PH TI Gemini, a dual tracker SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE AB Tracking through a turbulent atmosphere involves many challenges. In the pursuit of better tracking techniques Gemini, a dual tracker was developed. Intended as a research too, Gemini can be used to characterize anisoplanatism, wind, and other atmospheric effects on a frame by frame basis. In addition, one tracker can be converted to a pupil plane or wavefront sensor. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Tellez, JA (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 1 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 266 EP 273 DI 10.1117/12.356965 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800028 ER PT S AU Johnson, C VanAllen, R Dimmler, M Dillow, J AF Johnson, C VanAllen, R Dimmler, M Dillow, J BE Steiner, TD Merritt, PH TI Design & development of an acquisition, tracking, pointing & fire control system SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE fire control; ATP; systems engineering; airborne laser AB The ABL Acquisition, Tracking, Pointing and Fire Control systems functions are described. The key to the design process is a detailed simulation that models the controls, algorithms, engagement sequence, mode logic, passive track sensors, active track sensor (Intensified imager), plume phenomenology, active return from the target, and the effects of atmosphere. The application of the simulation to the design process is described, including passive track, active track, and kill assessment. Two field tests used to validate the simulation are briefly described. C1 USAF, Airborne Laser Syst Program Off, Kirtland AFB, NM 87117 USA. RP Johnson, C (reprint author), USAF, Airborne Laser Syst Program Off, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 288 EP 295 DI 10.1117/12.356968 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800030 ER PT S AU Washburn, DC AF Washburn, DC BE Steiner, TD Merritt, PH TI State equations for non-rational spectra SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE non-rational spectra; filtering; infinite dimensional filtering; L&G; Kalman filtering AB This paper develops an infinite dimensional theory for filtering and control in the presence of non-rational spectra. It begins with a review of the original work of A. V. Balakrishnan for the continuous time case. This work formulates an auxiliary state space signal model for the case of non-rational spectra. The result is the recovery of Kalman like signal generation models with the resulting separation principle for control. New results, based on unpublished notes of Balakrishnan, on discretization of the model are developed. Although the results can and will be generalized, this paper only covers the 1-d theory. C1 USAF, Res Lab, Directed Energy Directorate, Albuquerque, NM USA. RP Washburn, DC (reprint author), USAF, Res Lab, Directed Energy Directorate, Albuquerque, NM USA. NR 5 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 312 EP 323 DI 10.1117/12.356972 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800033 ER PT S AU Whiteley, MR AF Whiteley, MR BE Steiner, TD Merritt, PH TI Finite outer scale considerations for beam-steering optimization SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE ID EXPANSION COEFFICIENTS; TURBULENCE AB Finite turbulence outer scale attenuates turbulence power at low spatial frequencies, providing a finite variance for turbulence-induced phase. The temporal properties of low spatial-frequency aberrations such as tilt are affected directly by finite outer scale turbulence models. When optimal estimation techniques are used in beam-steering applications, the estimator form and its performance are related directly to the correlative properties of tilt and higher-order modes as determined by the value of Lo/D. In this work, we consider the effect of finite turbulence outer scale on the performance of optimal tilt compensation incorporating time-delayed tilt plus higher-order modes. The results indicate that while smaller values of Lo/D provide for higher Strehl ratios after tilt compensation, the Strehl ratio gain obtained through optimal compensation is reduced with decreasing values of Lo/D. For the relative aperture diameter D/r(0) = 5 and using time-delayed tilt plus higher-order modes through Zernike 15, the Strehl ratio gain with time delay upsilon tau/D = 0.5 is approximately 15 for L-0/D = 100. Under the same conditions, the Strehl ratio gain for L-0/D = 2 is approximately 3. C1 USAF, Airborne Laser Technol Branch, Res Lab, Kirtland AFB, NM 87117 USA. RP Whiteley, MR (reprint author), USAF, Airborne Laser Technol Branch, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 13 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 338 EP 348 DI 10.1117/12.356974 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800035 ER PT S AU Oppenheimer, MW Pachter, M AF Oppenheimer, MW Pachter, M BE Steiner, TD Merritt, PH TI Algorithm development for on-line control of the ABL SO AIRBORNE LASER ADVANCED TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Airborne Laser Advanced Technology CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE adaptive optics; correlation; realization; control ID PHASE-EXPANSION COEFFICIENTS; ATMOSPHERIC-TURBULENCE; SPATIAL CORRELATION AB In optics, Zernike orthonormal polynomials are used as a basis set for the expansion of wavefront phases. Due to the atmospheric turbulence-induced stochastic nature of the underlying processes involved, the spatial-temporal correlation functions of the Zernike polynomial phase expansion coefficients must be evaluated if adaptive optics is to be employed. In this paper, these correlation functions are developed using a layered atmospheric model and calculations for the first few low-order Zernike modes are performed. Using these correlation functions, an underlying linear dynamical system is identified. Within an acceptable error bound, the correlation functions of this system are representative of the calculated correlation functions. This system, in turn, provides the basis for the employment of advanced control and estimation concepts in an adaptive optics system that is being developed for the ABL. C1 USAF, Inst Technol, Dept Elect Engn, Wright Patterson AFB, OH 45433 USA. RP Oppenheimer, MW (reprint author), USAF, Inst Technol, Dept Elect Engn, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 12 TC 4 Z9 4 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 0-8194-3180-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3706 BP 349 EP 360 DI 10.1117/12.356975 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN69X UT WOS:000082635800036 ER PT S AU Power, GJ Rathbun, TF Worrell, SW AF Power, GJ Rathbun, TF Worrell, SW BE Shen, SS Descour, MR TI Restoration of images from an airborne unstabilized hyperspectral line scanner SO ALGORITHMS FOR MULTISPECTRAL AND HYPERSPECTRAL IMAGERY V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Multispectral and Hyperspectral Imagery V CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE hyperspectral; algorithm; image restoration; motion compensation AB An airborne hyperspectral line scanner is used to image the ground as the aircraft moves on a single trajectory. In reality, it may be difficult for the aircraft to maintain a perfectly steady course causing distortions in the imagery. So, special subsystems including stabilizers are used to maintain the hyperspectral line scanner on the proper course. If the subsystems of an airborne hyperspectral line scanner are malfunctioning or if the proper stabilizers are not available, then a technique is needed to restore the imagery. If no stabilizers are used on the airborne line scanner, but if aircraft navigation information is available including yaw, pitch and roll, then the restoration may be automated. However, if the stabilizers are malfunctioning or if the navigation information is corrupted or unavailable, then a technique is needed to restore the imagery. This paper introduces an automated technique for restoring hyperspectral images that was used on some images obtained for the Dynamic Data Base (DDB) program sponsored by the Defense Advanced Research Projects Agency (DARPA). The automated approach is based on image flow vectors obtained from the unstable image. The approach is introduced along with results that demonstrate how successful the restoration is at the feature level. C1 SNA, AFRL, Sensor ATR Technol Div, Air Force Res Lab, Wright Patterson AFB, OH 45433 USA. RP Power, GJ (reprint author), SNA, AFRL, Sensor ATR Technol Div, Air Force Res Lab, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 1 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 0-8194-3191-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3717 BP 169 EP 176 DI 10.1117/12.353035 PG 8 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BN65W UT WOS:000082518500016 ER PT S AU Genello, GJ Wicks, MC Soumekh, M AF Genello, GJ Wicks, MC Soumekh, M BE Zelnio, EG TI Alias-free processing of P-3 data SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE synthetc aperture radar; foliage penetrating radar ID SYNTHETIC-APERTURE RADAR AB This paper is concerned with multidimensional signal processing and image formation with FOliage PENetrating (FOPEN) airborne radar data which were collected by a Navy P-3 ultra wideband (UWB) radar in 1995 [Raw]. A commonly-used assumption for the processing of the P-3 data is that the beamwidth angle of the radar is limited to 35 degrees [Bes], [Goo]; provided that this assumption is valid, the PRF of the P-3 SAR system yields alias-free data in the slow-time Doppler domain. However, controlled measurements with the P-3 radar have indicated a beamwidth which exceeds 35 degrees [Raw]. In this paper, we examine a method for processing of the P-3 data in which the incorrect assumption that its radar beamwidth angle is limited to 35 degrees is not imposed. In this approach, a SAR processing scheme which enables the user to extract the SAR signature of a specific target area (digital spotlighting) is used to ensure that the resultant reconstructed SAR image is not aliased [S94], [S95], [S99]. The images which are formed via this method with 8192 pulses are shown to be superior in quality to the images which are formed via the conventional P-3 processor with 16386 pulses which was developed at the MIT Lincoln Laboratory [Bes]. In the presentation, we also introduce a method for converting the P-3 deramped data into its alias-free baseband echoed data; the signature of the Radio Frequency Interference (RFI) signals in the two-dimensional spectral domain of the resultant data is examined. C1 USAF, Res Lab, Radar Signal Proc Branch, Rome, NY 13441 USA. RP Genello, GJ (reprint author), USAF, Res Lab, Radar Signal Proc Branch, Rome, NY 13441 USA. NR 13 TC 1 Z9 1 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 189 EP 200 PG 12 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200018 ER PT S AU Bryant, M Garber, F AF Bryant, M Garber, F BE Zelnio, EG TI SVM classifier applied to the MSTAR public data set SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE support vector machines; SVM; structural risk minimization; SRM; MSTAR; ATR AB Support vector machines (SVM) are one of the most recent tools to be developed from research in statistical learning theory. The foundations of SVM were developed by Vapnik, and are gaining popularity within the learning theory community due to many attractive features and excellent demonstrated performance. However, SVM have not yet gained popularity within the synthetic aperture radar (SAR) automatic target recognition (ATR) community. The purpose of this paper is to introduce the concepts of SVM and to benchmark its performance on the Moving and Stationary Target Acquisition and Recognition (MSTAR) data set. C1 USAF, AFRL, SNAT, Washington, DC 20330 USA. RP Bryant, M (reprint author), USAF, AFRL, SNAT, Washington, DC 20330 USA. NR 5 TC 23 Z9 24 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 355 EP 360 DI 10.1117/12.357652 PG 6 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200033 ER PT S AU Layne, JR Simon, D AF Layne, JR Simon, D BE Zelnio, EG TI A multiple model estimator for a tightly coupled HRR automatic target recognition and MTI tracking system SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE multiple model estimation; coupled automatic target recognition and tracking systems AB The goal of this research is to exploit couplings between tracking and ATR systems employing high range resolution radar (HRRR) and moving target indicator (MTI) measurements. As will be shown, these systems are coupled via pose, kinematic, and association constraints. Exploiting these couplings results in a tightly coupled system with significantly improved performance. This problem deals with two different types of spaces, namely the continuous space kinematics (e.g. position and velocity) and the discrete space target type. A multiple model estimator (MME) was chosen for this problem. The MME consist of a bank of extended Kalman filters (one for each target type). The continuous space kinematics are dealt with via these extended Kalman filter. Further, the probability of each Kalman filter is computed and used to determine the corresponding discrete space target probability. Presented in this paper are empirical results that show improvement over conventional techniques. C1 AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. RP Layne, JR (reprint author), AFRL, SNAT, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. EM laynejr@sensors.wpafb.af.mil; dsimon+@andrew.cmu.edu NR 12 TC 4 Z9 4 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 0-8194-3195-8 J9 PROC SPIE PY 1999 VL 3721 BP 362 EP 373 DI 10.1117/12.357653 PG 12 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200034 ER PT S AU Westerkamp, JJ Fister, T Williams, R Mitchell, R AF Westerkamp, JJ Fister, T Williams, R Mitchell, R BE Zelnio, EG TI Robust feature-based Bayesian ground target recognition using decision confidence for unknown target rejection SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE HRR; ATR; ground targets; confidence; unknown targets AB The statistical feature-based (StaF) classifier is presented for robust high range resolution (HRR) radar moving ground target identification. The target features used for classification are the amplitude and location of HRR signature peaks. The peak features are not predetermined using the training data but are extracted on-the-fly from the observed HRR profile and are different for each target observation. A classifier decision is made after statistical evidence is accrued from each feature and across multiple looks. Decision uncertainty is estimated using a belief-based confidence measure. Classifier decisions are rejected if the decision uncertainty is too high since it is likely that the observed HRR profile is not in the classifier's target database. Robustness is achieved by using only peak features rather than the entire HRR profile (much of which is low-level scatterers buried in noise or simply noise) and by rejecting decisions with high uncertainty. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Westerkamp, JJ (reprint author), USAF, Res Lab, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 8 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 383 EP 394 DI 10.1117/12.357655 PG 12 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200036 ER PT S AU Williams, R Westerkamp, JJ Gross, DC Palomino, AP Kaufman, T Fister, T AF Williams, R Westerkamp, JJ Gross, DC Palomino, AP Kaufman, T Fister, T BE Zelnio, EG TI Analysis of a 1-D HRR moving target ATR SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE HRR; ATR; SAR; MTI; tracker accuracy; move-stop-move; QuickSAR AB This paper presents the performance of a multi-class, template-based, system-oriented High Range Resolution (HRR) Automatic Target Recognition (ATR) algorithm for ground moving targets. The HRR classifier assumes a target aspect estimate derived from the exploitation of moving target indication (MTI) mode target tracking to reduce the template search space. The impact of the Mn tracker target aspect estimate accuracy on the performance and robustness of the HRR ATR is investigated. Next, both individual and hybrid MTI/HRR and Synthetic Aperture Radar (SAR) model-based ATR algorithm results are presented. The hybrid ATR under consideration assumes the coordination of a multimode sensor to provide classification or continuous tracking of targets in a move-stop-move scenario. That is, a high-value moving target is tracked using the GMTI mode and its heading estimated. As the indicated target stops, the last GMTI tracker update is used to aid the SAR mode ATR target acquisition and classification. As the target begins to move again, the MTI-assisted HRR ATR target identification estimates are fused with the previous SAR ATR classification. The hybrid MTI/SAR/HRR ATR decision-level fusion provides a method for robust classification and/or continuous tracking of targets in move-stop-move cycles. Lastly, the baseline HRR ATR performance is compared to a QuickSAR (short dwell or non-square pixel SAR) ATR algorithm for varying cross-range resolutions. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Williams, R (reprint author), USAF, Res Lab, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 6 TC 4 Z9 4 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 413 EP 424 DI 10.1117/12.357658 PG 12 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200039 ER PT S AU Velten, VJ AF Velten, VJ BE Zelnio, EG TI Synthetic aperture radar (SAR) geometric invariants: Experimental results SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE synthetic aperture radar; scattering centers; geometric invariance; model-based vision ID ATR AB Synthetic Aperture Radar (SAR) sensors have many advantages over electro-optical sensors (EO) for target recognition applications, such as range-independent resolution and superior poor weather performance. However, the relative unavailability of SAR data to the basic research community has retarded analysis of the fundamental invariant properties of SAR sensors relative to the extensive invariant literature for EO, and in particular photographic sensors. Prior work that was reported at this conference has developed the theory of SAR invariants based on the radar scattering center concept. This paper will give several examples of invariant configurations of SAR scatterers from measured SAR image data. C1 USAF, Res Lab, AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. RP Velten, VJ (reprint author), USAF, Res Lab, AFRL, SNAT, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 25 TC 2 Z9 2 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 520 EP 531 DI 10.1117/12.357668 PG 12 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200048 ER PT S AU Ryan, PA Wilson, KS AF Ryan, PA Wilson, KS BE Zelnio, EG TI Phenomenology metric development for SAR scene modeling tools SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE Synthetic Aperture Radar (SAR) modeling; validation metrics AB Synthetic Aperture Radar (SAR) image modeling tools are of high interest to Automatic Target Recognition (ATR) algorithm evaluation because they allow the testing of ATRs over a wider range of extended operating conditions (EOCs). Typical EOCs include target aspect, target configuration, target obscuration, and background terrain variations. Since the phenomenology fidelity of the synthetic prediction techniques is critical for ATR evaluation, metric development for complex scene prediction is needed for accurate ATR performance estimation. An image domain hybrid prediction technique involves the insertion of a synthetic target chip into a measured image background. Targets in terrain scenes will be predicted and compared with similar measured data scenarios. Shadow region histograms and terrain region histograms will be used to develop some first generation metrics for phenomenology validation of hybrid SAR prediction techniques. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Ryan, PA (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 2 TC 1 Z9 1 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 582 EP 588 DI 10.1117/12.357673 PG 7 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200053 ER PT S AU Temple, MA Wilson, KS AF Temple, MA Wilson, KS BE Zelnio, EG TI Probabilistic backscatter coefficient generating function SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE backscatter; ground clutter; clutter modeling; clutter reflectivity AB A probabilistic backscatter coefficient generating function (CGF) is introduced which produces realistic backscatter coefficient values for various terrain types over all incidence angles. The CGF was developed in direct support of a multilayer 3-D clutter modeling effort which successfully incorporated probabilistic clutter reflectivity characteristics and measured terrain elevation data to enhance clutter suppression and improve Signal-to-Clutter Ratio performance in radar applications'. This probabilistic clutter modeling approach is in sharp contrast to traditional 2-D modeling techniques which typically include deterministic backscatter characteristics and assume constant terrain features within regions of interest. The functional form and parametric representation of the CGF were empirically determined by comparison with published backscatter data for nine different terrain "types," including, soil and rock, shrubs, trees, short vegetation, grasses, dry snow, wet snow, road surfaces, and urban areas'. The statistical properties of the output, i.e., the mean and standard deviation, match published measured values to the number of significant figures reported. Likewise, the CGF output frequency of occurrence closely matches measured terrain data frequency of occurrence; a Chi-Square test fails to reject the method at a 0.05 level of significance, indicating a high level of confidence in the results. As developed, the CGF provides a computationally efficient means for incorporating probabilistic clutter characteristics into both simple and complex radar models by accurately reflecting the probabilistic scattering behavior associated with real terrain. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Temple, MA (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 3 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 644 EP 649 DI 10.1117/12.357679 PG 6 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200059 ER PT S AU Ross, TD Bradley, JJ Hudson, LJ O'Connor, MP AF Ross, TD Bradley, JJ Hudson, LJ O'Connor, MP BE Zelnio, EG TI SAR ATR - So what's the problem? - An MSTAR perspective SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE target recognition; ATR; synthetic aperture radar; SAR; operating conditions; evaluation; testing AB What makes synthetic aperture radar (SAR) automatic target recognition (ATR) hard? This question is explored by reviewing target, environment, and sensor variability and how they affect SAR images and target recognition in SAR images. Each of these categories of operating conditions (OCs) is reviewed first with a wide open "real world" scope and then comparing that to the extensive MSTAR SAR data collections. The target OC review considers increasingly fine target categories, from class to type to versions, and then configuration, articulation, damage, and moving-part variants. The environment OC considers topological properties, that might affect 6-DOF pose and terrain obscuration, volumetric (vegetation, snow, ...) and surface scattering properties, and occlusion, layover, and adjacency issues. The sensor OC review is limited to outlining the important properties of SAR imaging systems, such as their variation in frequency, PRF, BW, polarization, depression, squint, SNR, etc. SAR and optical images are used to illustrate OC dimensions. This review is limited to open literature sources and is from an ATR rather than a domain expert perspective. However, this space of SAR ATR OCs will eventually need to be understood before we will truly know the SAR ATR problem. C1 USAF, Res Lab, Sensors Directorate, AFRL,SNA, Wright Patterson AFB, OH 45433 USA. RP Ross, TD (reprint author), USAF, Res Lab, Sensors Directorate, AFRL,SNA, Wright Patterson AFB, OH 45433 USA. NR 5 TC 31 Z9 37 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 662 EP 672 DI 10.1117/12.357681 PG 11 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200061 ER PT S AU Power, GJ Weisenseel, RA AF Power, GJ Weisenseel, RA BE Zelnio, EG TI ATR subsystem performance measures using manual segmentation of SAR target chips SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE SAR; segmentation; manual segmentation; MSTAR; target recognition AB Target recognition research for Synthetic Aperture Radar (SAR) has been made easier with the introduction of target chip sets. The target chips typically are of good quality and consist of three regions: target, shadow and background clutter. Target chip sets allow recognition researchers to bypass the quality filtering and detection phases of the automatic recognition process. So, the researcher can focus on segmentation and matching techniques. A manual segmentation process using supervised quality control is introduced in this paper. Using 'goodness of fit' measures the quality of manual segmentation on SAR target chips is presented. Using the expected metrics associated with the manual segmentation process, the performance of automated segmentation techniques can be evaluated. The approach of using manual segmentation to evaluate the performance of automated segmentation techniques is presented by demonstrating the results on a simple automated segmentation technique that incorporates speckle removal and segmentation. C1 USAF, Res Lab, Target Recognit Branch, AFRL,SNAT, Wright Patterson AFB, OH 45433 USA. RP Power, GJ (reprint author), USAF, Res Lab, Target Recognit Branch, AFRL,SNAT, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 4 TC 2 Z9 3 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 685 EP 692 DI 10.1117/12.357683 PG 8 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200063 ER PT S AU Ross, TD Mossing, JC AF Ross, TD Mossing, JC BE Zelnio, EG TI The MSTAR evaluation methodology SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE evaluation; automatic target recognition; synthetic aperture radar; extended operating conditions; performance sensitivity; algorithm evaluation AB MSTAR is a SAR ATR exploratory development effort and has devoted significant resources to regular independent evaluations. This paper will review the current state of the MSTAR evaluation methodology. The MSTAR evaluations have helped bring into focus a number of issues related to SAR ATR evaluation (and often ATR evaluation in general). The principles from MSTAR's three years of evaluations are explained and evaluation specifics, from the selection of test conditions and figures-of-merit to the development of evaluation tools, are reported. MSTAR now has a more mature understanding of the critical aspects of independence in evaluation and of the general relationship between evaluation and the program's goals and the systems engineering necessary to meet those goals. MSTAR has helped to develop general concepts, such as assessing ATR extensibility and scalability. Other specific contributions to evaluation methods, such as nuances in figure-of-merit definitions, are also detailed. In summary, this paper describes the MSTAR framework for the design, execution, and interpretation of SAR ATR evaluations. C1 USAF, Res Lab, Sensors Directorate, AFRL,SNA, Wright Patterson AFB, OH 45433 USA. RP Ross, TD (reprint author), USAF, Res Lab, Sensors Directorate, AFRL,SNA, Wright Patterson AFB, OH 45433 USA. NR 9 TC 12 Z9 15 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 705 EP 713 DI 10.1117/12.357686 PG 9 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200065 ER PT S AU Blasch, E Alsing, SG Bauer, KW AF Blasch, E Alsing, SG Bauer, KW BE Zelnio, EG TI Comparison of Bootstrap and Prior-probability synthetic data balancing methods for SAR target recognition SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE SAR; bootstrap methods; under sampling distributions; ATR AB This paper compares bootstrap techniques with prior probability synthetic data balancing to determine which method is more effective for SAR target recognition. A bootstrap method resamples from the original target data to present more target examples to the ATR for training. Prior probability synthetic data balancing prevents the double counting of information by just resampling the smaller set. However, prior probability synthetic data balancing necessitates equivalent distributions from data sets which reduces the data set to the size of the smaller see. A new type of receiver operating characteristic (ROC) curve, based on varying the proportion of target data in the data set is presented to compare the two methods. The paper demonstrates the implementation of the data balancing of two targets from the Moving and Stationary Target Acquisition and Recognition (MSTAR) data set using an entropy metric for target classification. C1 USAF, Res Lab, SNAT, Wright Patterson AFB, OH 45433 USA. RP Blasch, E (reprint author), USAF, Res Lab, SNAT, 2241 Avion Cir, Wright Patterson AFB, OH 45433 USA. NR 13 TC 1 Z9 1 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 740 EP 747 DI 10.1117/12.357689 PG 8 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200068 ER PT S AU Pierson, WE Ulug, B Ahalt, SC AF Pierson, WE Ulug, B Ahalt, SC BE Zelnio, EG TI Boundary methods for mode estimation SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VI CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE pattern recognition mode estimation; model order estimation; boundary methods ID IDENTIFICATION; COMPLEXITY AB This paper investigates the use of Boundary Methods (BMs), a collection of tools used for distribution analysis, as a method for estimating the number of modes associated with a given data set. Model order information of this type is required by several pattern recognition applications. The BM technique provides a novel approach to this parameter estimation problem and is comparable in terms of both accuracy and computations to other popular mode estimation techniques currently found in the literature and automatic target recognition applications. This paper explains the methodology used in the BM approach to mode estimation. Also, this paper quickly reviews other common mode estimation techniques and describes the empirical investigation used to explore the relationship of the BM technique to other mode estimation techniques. Specifically, the accuracy and computational efficiency of the BM technique are compared quantitatively to the a mixture of Gaussian (MOG) approach and a k-means approach to model order estimation. The stopping criteria of the MOG and k-means techniques is the Akaike Information Criteria (AIC). C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Pierson, WE (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 27 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 0-8194-3195-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3721 BP 797 EP 808 PG 12 WC Telecommunications SC Telecommunications GA BN77S UT WOS:000082902200072 ER PT J AU Nolinske, T Millis, B AF Nolinske, T Millis, B TI Cooperative learning as an approach to pedagogy SO AMERICAN JOURNAL OF OCCUPATIONAL THERAPY LA English DT Article DE cooperative behavior; education; teaching methods AB Lecture-based pedagogical approaches cannot adequately prepare students in professional and technical occupational therapy programs. Faculty members in other disciplines are turning to a well-known and well-researched teaching approach called cooperative learning, which is more carefully structured and defined than most other forms of small group learning. Cooperative learning includes several key principles: positive interdependence, individual responsibility, appropriate grouping, group maintenance, cooperative skills, and promotive (interaction) time. This article provides ideas for managing the classroom with cooperative learning activities and describes eight of them: Three-Step Interview, Roundtable, Think-Pair-Share, Structured Problem Solving, Send/Pass-a-Problem, Generic Question Stems, Double Entry Journal, and Dyadic Essay Confrontation. Each activity is applied to content embedded in professional and technical occupational therapy curricula. A cooperative learning approach to evaluating learning is also presented. C1 Lincoln Pk Zoo, Dept Educ, Chicago, IL USA. Profess Dev Consultants, Oak Pk, IL 60301 USA. USAF Acad, Colorado Springs, CO 80840 USA. RP Nolinske, T (reprint author), Lincoln Pk Zoo, Dept Educ, Chicago, IL USA. NR 30 TC 11 Z9 11 U1 0 U2 5 PU AMER OCCUPATIONAL THERAPY ASSOC, INC PI BETHESDA PA 4720 MONTGOMERY LANE, BETHESDA, MD 20814-3425 USA SN 0272-9490 J9 AM J OCCUP THER JI Am. J. Occup. Ther. PD JAN-FEB PY 1999 VL 53 IS 1 BP 31 EP 40 PG 10 WC Rehabilitation SC Rehabilitation GA 158HA UT WOS:000078108900006 PM 9926216 ER PT J AU Dockall, HD Baker, JE AF Dockall, HD Baker, JE TI Skeletal health of an elderly sample of Civil War era veterans. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 USA, Cent Identificat Lab, Hickam AFB, HI 96853 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 1999 SU 28 BP 120 EP 120 PG 1 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500111 ER PT J AU Domett, KM AF Domett, KM TI Oral health in southeast Asia. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 USA, Cent Identificat Lab, Hickam AFB, HI 96853 USA. Texas A&M Univ, Dept Anthropol, College Stn, TX 77843 USA. RI Domett, Kate/J-4105-2014 OI Domett, Kate/0000-0001-5091-3105 NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 1999 SU 28 BP 120 EP 121 PG 2 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 184JE UT WOS:000079607500112 ER PT J AU Sanders, TG Tirman, PFJ Linares, R Feller, JF Richardson, R AF Sanders, TG Tirman, PFJ Linares, R Feller, JF Richardson, R TI The glenolabral articular disruption lesion: MR arthrography with arthroscopic correlation SO AMERICAN JOURNAL OF ROENTGENOLOGY LA English DT Article ID SHOULDER AB OBJECTIVE. The purpose of this study was to describe the MR arthrography appearance of the glenolabral articular disruption (GLAD) lesion. Proper diagnosis of this lesion is important because it can be a source of persistent shoulder pain that requires surgical repair and because it is often difficult to diagnose clinically. MATERIALS AND METHODS, Findings on MR arthrography were retrospectively correlated with the clinical histories and physical examination findings of six patients in whom we saw the typical appearance of the GLAD lesion. Four of these patients underwent follow-up arthroscopy that included surgical proof of GLAD lesions. RESULTS, Five of the six patients had a documented glenohumeral impaction injury associated with an abducted externally rotated shoulder. All six patients had persistent shoulder pain, but their shoulders were stable during routine examination. In all patients, MR arthrography showed a superficial tear of the anteroinferior labrum with an adjacent articular cartilage injury. The tom labrum remained firmly attached to the anterior scapular periosteum, and contrast material was seen to extend into the labral fear and cartilaginous defect. CONCLUSION. The MR arthrography findings of GLAD lesions include a nondisplaced tear of the anteroinferior labrum with an adjacent chondral injury. The pattern of chondral injury can range from a cartilaginous flap tear to a depressed osteochondral injury of the articular cartilage and underlying bone. C1 David Grant US AF Med Ctr, Dept Radiol, Travis AFB, CA 94535 USA. San Francisco Magnet Resonance Ctr, San Francisco, CA 94118 USA. Desert Orthoped Ctr, Rancho Mirage, CA 92270 USA. RP Sanders, TG (reprint author), David Grant US AF Med Ctr, Dept Radiol, 101 Bodin Cir, Travis AFB, CA 94535 USA. NR 10 TC 55 Z9 55 U1 0 U2 0 PU AMER ROENTGEN RAY SOC PI RESTON PA 1891 PRESTON WHITE DR, SUBSCRIPTION FULFILLMENT, RESTON, VA 22091 USA SN 0361-803X J9 AM J ROENTGENOL JI Am. J. Roentgenol. PD JAN PY 1999 VL 172 IS 1 BP 171 EP 175 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 151WE UT WOS:000077743000038 PM 9888763 ER PT J AU Coston, SD Pelton, JJ AF Coston, SD Pelton, JJ TI Success of cervical exploration for patients with asymptomatic primary hyperparathyroidism SO AMERICAN JOURNAL OF SURGERY LA English DT Article ID FOLLOW-UP; SURGERY; PARATHYROIDECTOMY; MANAGEMENT; DISEASE AB BACKGROUND: This Study examined the success and safety of cervical exploration in patients with asymptomatic primary hyperparathyroidism compared with those with symptomatic disease. METHODS: Records of patients undergoing cervical exploration for primary hyperparathyroidism from June 1990 to October 1996 were reviewed. Patients were divided into three groups: (1) asymptomatic, (2) symptomatic, and (3) afflicted (those with associated complications). Information collected consisted of preoperative and postoperative symptoms, serum calcium and parathyroid hormone levels (PTH), and descriptions of pathologic and operative findings. RESULTS: Sixty-one patients were identified, Nineteen (31%) had no symptoms, 21 (34%) had subjective symptoms, and 21 had associated conditions, as described. Average preoperative and postoperative calcium levers were 11.5 mg% and 8.5 mg%, respectively. Average PTH levels also fell from 142 pg/mL to 49 pg/mL after surgery. Preoperative and postoperative calcium and PTH levels for the three groups showed no significant differences. The success of surgery in identifying pathology ranged from 90.5% to 95%, and again showed no difference among the three groups. Long-term morbidity (>6 months) in ail groups was 0%. CONCLUSIONS: Cervical exploration and parathyroidectomy for asymptomatic primary hyperparathryoidism is safe and has similar success rates in identifying pathology and correcting biochemical abnormalities compared with patients with symptomatic disease. Am J Surg. 1999; 177:69-74. (C) 1999 by Excerpta Medica, Inc. C1 Wilford Hall USAF Med Ctr, Dept Gen Surg, Sect Surg Oncol, San Antonio, TX 78236 USA. RP Pelton, JJ (reprint author), Wilford Hall USAF Med Ctr, MKSG, Sect Surg Oncol, 2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 26 TC 7 Z9 12 U1 0 U2 0 PU CAHNERS PUBL CO PI NEW YORK PA 249 WEST 17 STREET, NEW YORK, NY 10011 USA SN 0002-9610 J9 AM J SURG JI Am. J. Surg. PD JAN PY 1999 VL 177 IS 1 BP 69 EP 74 DI 10.1016/S0002-9610(98)00307-9 PG 6 WC Surgery SC Surgery GA 166AM UT WOS:000078554100015 PM 10037312 ER PT J AU Taverna, PJ Mayfield, H Andrews, ARJ AF Taverna, PJ Mayfield, H Andrews, ARJ TI Further determination of cadmium ions in water by an electrochemiluminescence method SO ANALYTICAL LETTERS LA English DT Article DE chelation enhanced electrochemiluminescence; cadmium; terpyridine; bipyridine; aqueous solution ID LUMINESCENT METAL-COMPLEXES; RUTHENIUM(II) AB Two new electrochemiluminescence (ECL) reactions in aqueous solution involving cadmium(II) ions are reported. The ECL reaction occurs in the presence of a common co-reactant, tripropylamine (TPA), and either of two organic ligands, 2,2':6',2 "-terpyridine or 2,2'-bipyridine. The reaction is presumed to arise from the metal-ligand complex and the co-reactant. Conditions for ECL emission were optimised and a calibration graph constructed. Emission was linear over the range 10-1 000 ppb; The calculated limits of detection (LOD) were 8 and 50 ppb using terpyridine and bipyridine, respectively. Comparison with a previously reported reaction involving cadmium(II) ions and 1,10-phenathroline is made. C1 Tulane Univ, Dept BME, New Orleans, LA 70118 USA. AL, EQ, Tyndall AFB, FL 32403 USA. Ohio Univ, Dept Chem & Biochem, Ctr Intelligent Chem Instrumentat, Athens, OH 45701 USA. RP Taverna, PJ (reprint author), Tulane Univ, Dept BME, 500 Lindy Boggs, New Orleans, LA 70118 USA. NR 11 TC 2 Z9 2 U1 1 U2 3 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0003-2719 J9 ANAL LETT JI Anal. Lett. PY 1999 VL 32 IS 9 BP 1821 EP 1833 DI 10.1080/00032719908542936 PG 13 WC Chemistry, Analytical SC Chemistry GA 214TC UT WOS:000081342800010 ER PT J AU Christe, KO Wilson, WW Sheehy, JA Boatz, JA AF Christe, KO Wilson, WW Sheehy, JA Boatz, JA TI N-5(+): A novel homoleptic polynitrogen ion as a high energy density material SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article DE density functional calculations; isotopic labeling; nitrogen; NMR spectroscopy; vibrational spectroscopy ID COUPLED-CLUSTER CALCULATIONS; RESONANCE CHEMICAL-SHIFTS; GAUSSIAN-BASIS SETS; ELECTRON CORRELATION; N-4(+); SPECTROSCOPY; EXCHANGE; CATION; ATOMS; N4+ C1 USAF, Res Lab, Propuls Sci & Adv Concepts Div, Edwards AFB, CA 93524 USA. Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. RP Christe, KO (reprint author), USAF, Res Lab, Propuls Sci & Adv Concepts Div, Edwards AFB, CA 93524 USA. RI Christe, Karl/O-4885-2014 OI Christe, Karl/0000-0003-0661-5519 NR 39 TC 323 Z9 338 U1 2 U2 28 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 1999 VL 38 IS 13-14 BP 2004 EP 2009 DI 10.1002/(SICI)1521-3773(19990712)38:13/14<2004::AID-ANIE2004>3.0.CO;2-7 PG 6 WC Chemistry, Multidisciplinary SC Chemistry GA 217RC UT WOS:000081511900039 ER PT J AU Flynn, MR Gatano, BL McKernan, JL Dunn, KH Blazicko, BA Carlton, GN AF Flynn, MR Gatano, BL McKernan, JL Dunn, KH Blazicko, BA Carlton, GN TI Modeling breathing-zone concentrations of airborne contaminants generated during compressed air spray painting SO ANNALS OF OCCUPATIONAL HYGIENE LA English DT Article DE exposure modeling; spray-painting; ventilation; transfer efficiency; dimensional analysis ID ATOMIZERS AB This paper presents a mathematical model to predict breathing-zone concentrations of airborne contaminants generated during compressed air spray painting in cross-flow ventilated booths. The model focuses on characterizing the generation and transport of overspray mist. It extends previous work on conventional spray guns to include exposures generated by HVLP guns. Dimensional analysis and scale model wind-tunnel studies are employed using non-volatile oils, instead of paint, to produce empirical equations for estimating exposure to total mass. Results indicate that a dimensionless breathing zone concentration is a nonlinear function of the ratio of momentum flux of air from the spray gun to the momentum flux of air passing through the projected area of the worker's body. The orientation of the spraying operation within the booth is also very significant, The exposure model requires an estimate of the contaminant generation rate, which is approximated by a simple impactor model. The results represent an initial step in the construction of more realistic models capable of predicting exposure as a mathematical function of the governing parameters. (C) 1999 British Occupational Hygiene Society, Published by Elsevier Science Ltd. C1 Univ N Carolina, Dept Environm Sci & Engn, Chapel Hill, NC 27599 USA. Dept Environm & Nat Resources, Raleigh, NC 27611 USA. NIOSH, Cincinnati, OH 45226 USA. USAF, Armstrong Lab, Ind Hyg Branch, Brooks AFB, TX 78235 USA. RP Flynn, MR (reprint author), Univ N Carolina, Dept Environm Sci & Engn, Chapel Hill, NC 27599 USA. RI Dunn, Kevin/I-2195-2012 FU NIOSH CDC HHS [R01/OH02858] NR 17 TC 15 Z9 15 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0003-4878 J9 ANN OCCUP HYG JI Ann. Occup. Hyg. PD JAN PY 1999 VL 43 IS 1 BP 67 EP 76 DI 10.1016/S0003-4878(98)00078-7 PG 10 WC Public, Environmental & Occupational Health; Toxicology SC Public, Environmental & Occupational Health; Toxicology GA 164YP UT WOS:000078491400006 PM 10028895 ER PT J AU Pohl, EA Dietrich, DL AF Pohl, EA Dietrich, DL TI Optimal Stress Screening strategies for multi-component systems sold under warranty: The case of phase-type lifetimes SO ANNALS OF OPERATIONS RESEARCH LA English DT Article DE ESS; renewal function; mixed distributions; phase-type distribution; life-cycle cost model; warranty ID OPTIMAL BURN-IN; RENEWAL; RELIABILITY; MODEL AB Environmental Stress Screening (ESS) is employed to reduce, if not eliminate, the occurrence of early field failures. This paper examines the necessary trade-offs between the reduction in warranty costs and the increase in manufacturing costs associated with optimal stress screening strategies. A multi-level ESS model is presented for a multi-component electronic system. Screening can be performed at component, unit, and system levels. Components and connections are assumed to come from good and substandard populations and their time-to-failure distributions are modeled by mixed distributions. The majority of ESS models found in the literature assume that the time-to-failure distributions are exponential. The exponential distribution is used primarily to take advantage of its mathematical tractability. This paper generalizes previous work by modeling component and connection lifetimes with phase-type distributions. Phase-type distributions offer the advantage of mathematical tractability as well as versatility in the family of distributions they can represent. To date there is no significant research into the impact that the selection of a lifetime distributions for modeling the failure process has on ESS decisions. In this paper, we evaluate screening strategies for several lifetime distributions. Numerical examples are provided to illustrate the effect of various model parameters on the optimal stress screening strategy. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. Univ Arizona, Tucson, AZ 85721 USA. RP Pohl, EA (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 52 TC 6 Z9 6 U1 0 U2 1 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0254-5330 J9 ANN OPER RES JI Ann. Oper. Res. PY 1999 VL 91 BP 137 EP 161 DI 10.1023/A:1018989404805 PG 25 WC Operations Research & Management Science SC Operations Research & Management Science GA 225QT UT WOS:000081972800010 ER PT J AU Zorn, WL Deckro, RF Lehmkuhl, LJ AF Zorn, WL Deckro, RF Lehmkuhl, LJ TI Modeling diminishing marginal returns in a hierarchical inventory system of reparable spare parts SO ANNALS OF OPERATIONS RESEARCH LA English DT Article DE hierarchical inventory systems; linear programming; parametric programming; reparable spares AB Safety stock levels of reparable spare parts in a hierarchical inventory structure are determined relative to the marginal improvement to end item availability provided by each stock level. This research is focused on the United States Air Force (USAF) hierarchical inventory and repair system as modeled by the Multi-Echelon-Technique-for-Recoverable-Item-Control (METRIC) methodology. A piecewise linear modeling framework is introduced based on output from the Aircraft Availability Model (AAM), a model that is part of the METRIC family of models. The underlying nature of the piecewise linear formulation provides integer stock levels with continuous decision variables. This model provides the highest attainable end-item availability relative to an inventory of reparable spare parts. Additionally, the model provides a robust platform for the conduct of extensive post-optimality analysis. While this research focuses on the METRIC family of models, the methodology developed may be applied to any hierarchical inventory of reparable spares that conforms to the model's underlying mathematical structure. C1 USAF, Dept Operat Sci, Inst Technol, Wright Patterson AFB, OH 45433 USA. USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. RP Zorn, WL (reprint author), USAF, Dept Operat Sci, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 11 TC 1 Z9 2 U1 1 U2 5 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 0254-5330 J9 ANN OPER RES JI Ann. Oper. Res. PY 1999 VL 91 BP 319 EP 337 DI 10.1023/A:1018962126187 PG 19 WC Operations Research & Management Science SC Operations Research & Management Science GA 225QT UT WOS:000081972800020 ER PT S AU Tran, TH Murdock, WP Pohl, EA AF Tran, TH Murdock, WP Pohl, EA GP IEEE TI Bayesian analysis for system reliability inferences SO ANNUAL RELIABILITY AND MAINTAINABILITY SYMPOSIUM, 1999 PROCEEDINGS SE PROCEEDINGS : ANNUAL RELIABILITY AND MAINTAINABILITY SYMPOSIUM LA English DT Article; Proceedings Paper CT International Symposium on Product Quality and Integrity - Managing Uncertainty CY JAN 18-21, 1999 CL WASHINGTON, D.C. SP IEEE Reliabil Soc, Amer Inst Aeronaut & Astronaut, Inst Environm Sci & Technol, Soc Automot Engineers Inc, Soc Reliabil Engineers, Amer Soc Qual Electr Div, Inst Ind Engineers, Soc Logist Engineers, Syst Safety Soc, Amer Soc Qual Reliabil Div DE Bayes analysis; reliability prediction; reliability estimates; test and evaluation AB Due to declining defense budgets, operational test and evaluation programs for military systems have been downsized. One significant result is less system operational test data. This leads to lower classical confidence inferences on critical measures of performance such as system reliability. This paper explores the use of Bayesian methods to compensate for this decrease in test data by integrating developmental test and evaluation data into the operational test and evaluation phase. Specifically, the reliability of a series system, a parallel system and a classic bridge system are examined over a range of mission times. Components in this study are assumed to have exponential lifetimes. Using simulated data for the three systems, the Bayesian methods produce tighter probability intervals for the system reliability than the confidence intervals found through classical inference methods. C1 USAF, Mat Command, Study & Anal Grp, Wright Patterson AFB, OH 45433 USA. RP Tran, TH (reprint author), USAF, Mat Command, Study & Anal Grp, Wright Patterson AFB, OH 45433 USA. NR 7 TC 1 Z9 3 U1 0 U2 4 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-144X BN 0-7803-5143-6 J9 P A REL MAI PY 1999 BP 151 EP 157 DI 10.1109/RAMS.1999.744111 PG 7 WC Engineering, Multidisciplinary SC Engineering GA BM43V UT WOS:000078742800025 ER PT S AU Reineke, DM Murdock, WP Pohl, EA Rehmert, I AF Reineke, DM Murdock, WP Pohl, EA Rehmert, I GP IEEE TI Improving availability and cost performance for complex systems with preventive maintenance SO ANNUAL RELIABILITY AND MAINTAINABILITY SYMPOSIUM, 1999 PROCEEDINGS SE PROCEEDINGS : ANNUAL RELIABILITY AND MAINTAINABILITY SYMPOSIUM LA English DT Article; Proceedings Paper CT International Symposium on Product Quality and Integrity - Managing Uncertainty CY JAN 18-21, 1999 CL WASHINGTON, D.C. SP IEEE Reliabil Soc, Amer Inst Aeronaut & Astronaut, Inst Environm Sci & Technol, Soc Automot Engineers Inc, Soc Reliabil Engineers, Amer Soc Qual Electr Div, Inst Ind Engineers, Soc Logist Engineers, Syst Safety Soc, Amer Soc Qual Reliabil Div DE availability; preventive maintenance; competing risks; life cycle costs; decreasing mean residual life; multi-mode repair AB This paper investigates improving system limiting availability and expected system cost rate for a complex system through age replacement preventive maintenance (PM). This study defines the complex system as classic bridge reliability structure consisting of 5 independent subsystems. A competing risk model is used for each subsystem's unique life distribution. This model includes two independent modes of failure for each subsystem. We assume the expected system failure repair time and PM action time are known or may be estimated. System-level age replacement PM models are developed for both system limiting availability and expected system cost rate. Often, both availability and cost performance are critical system characteristics. A methodology is presented that allows tradeoffs between availability and cost to be evaluated, The paper demonstrates the methodology for a specific example. The maintenance strategy assumes that failed subsystems are maintained according to their failure mode and working components are preventively maintained. This strategy applies whether failure maintenance or PM action is required. This strategy is selected, since, in terms of maintenance service, it lies between the extremes of pure system-level maintenance and independent subsystem-level maintenance. Limitations of the system-level maintenance strategy are identified. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Murdock, WP (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 4 TC 9 Z9 9 U1 0 U2 0 PU I E E E PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-144X BN 0-7803-5143-6 J9 P A REL MAI PY 1999 BP 383 EP 388 DI 10.1109/RAMS.1999.744148 PG 6 WC Engineering, Multidisciplinary SC Engineering GA BM43V UT WOS:000078742800061 ER PT S AU Carter, MA Oxley, ME AF Carter, MA Oxley, ME BE Priddy, KL Keller, PE Fogel, DB Bezdek, JC TI Generalized measures of artificial neural network capabilities SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications and Science of Computational Intelligence II CY APR 05-08, 1999 CL ORLANDO, FL SP SPIE - Int Soc Opt Engn DE artificial neural networks; capability measures; combinatorial geometry; invariants; V-C dimension AB Current measures of an artificial neural networks (ANN) capability are the V-C dimension and its variations. These measures may be underestimating capabilities (in the primal sense) and hence overestimating the required number of examples for learning (in the dual sense). This is a result of relying on a single invariant description of the problem set, which is cardinality, and requiring worst case geometries and colorings. Generalization of a capability measure allows aligning the measure with desired characterisitics of the problem sets. We present a mathematical framework in which to express other desired invariant descriptors of a. capability measure, and guarantee proper application of the measure to ANNs. We define a collection of invariants defined on the problem space that yield new capability measures of ANNs. A specific example of an invariant is given which is based on geometric complexity of the problem set and yields a new measure of ANNs called the Ox-Cart dimension. C1 USAF, Natl Air Intelligence Ctr, Wright Patterson AFB, OH 45433 USA. RP Carter, MA (reprint author), USAF, Natl Air Intelligence Ctr, 4115 Hebble Creek Rd, Wright Patterson AFB, OH 45433 USA. NR 5 TC 2 Z9 2 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 0-8194-3196-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3722 BP 36 EP 47 DI 10.1117/12.342875 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BM94R UT WOS:000080213000003 ER PT S AU Oxley, ME Carter, MA AF Oxley, ME Carter, MA BE Priddy, KL Keller, PE Fogel, DB Bezdek, JC TI Evaluating the Vapnik-Chervonenkis dimension of artificial neural networks using the Poincare polynomial SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications and Science of Computational Intelligence II CY APR 05-08, 1999 CL ORLANDO, FL SP SPIE - Int Soc Opt Engn DE artificial neural networks; Vapnik-Chervonenkis (V-C) dimension; Poincare polynomial; combinatorial geometry; hyperplane arrangements; lattice theory AB The Vapnik-Chervonenkis (V-C) dimension of a set, of functions representing a feed-forward, multi-layered, single output artificial neural network (ANN) with hard-limited activation functions can be evaluated using the Poincare polynomial of the implied hyperplane arrangement. This ANN geometrically is a hyperplane arrangement configured to dichotomize a signed set (i.e., a two-class set). Since it is known that the cut-intersections of the hyperplane arrangement; forms a semi-lattice, then the Poincare polynomial can be used to evaluate certain geometric invariants of this semi-lattice, in particular, the cardinality of the resultant chamber set of the arrangements, which is shown to be the V-C dimension. From this theory comes a stable formula to compute the V-C dimension values. C1 USAF, Inst Technol, Dept Math & Stat, Wright Patterson AFB, OH 45433 USA. RP Oxley, ME (reprint author), USAF, Inst Technol, Dept Math & Stat, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 10 TC 1 Z9 1 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 0-8194-3196-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3722 BP 68 EP 75 DI 10.1117/12.342902 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BM94R UT WOS:000080213000006 ER PT S AU Armstrong, EE Hayat, MM Hardie, RC Torres, SN Yasuda, B AF Armstrong, EE Hayat, MM Hardie, RC Torres, SN Yasuda, B BE Tescher, AG TI Non-uniformity correction for improved registration and high-resolution image reconstruction in IR imagery SO APPLICATIONS OF DIGITAL IMAGE PROCESSING XXII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications of Digital Image Processing XXII CY JUL 20-23, 1999 CL DENVER, CO SP SPIE DE non-uniformity; registration; microscanning; image reconstruction; image processing ID NONUNIFORMITY CORRECTION AB It is well known that non-uniformity noise in focal-plane array (FPA) sensors, which is due to the pixel-to-pixel variation in the detectors' responses, can considerably degrade the quality of images since it results in a fixed pattern that is superimposed on the true scene. This paper addresses the benefits of non-uniformity correction (NUC) pre-processing on the performance of a number of existing post-processing algorithms. The post-processing applications considered are image registration (motion compensation) and high-resolution image reconstruction from a sequence of blurred and undersampled images. The accuracy of motion estimation in the presence of non-uniformity noise is investigated in terms of the standard deviation of the gain and the offset of the FPA detectors. Two recently reported scene-based NUC techniques are employed to pre-process the FPA output prior post-processing. The first NUC technique is based on the assumption that all pixels experience the same range of irradiance over a sufficiently long sequence of frames (constant-range assumption), and the second NUC technique is registration-based and can be used recursively. It is shown that NUC improves the accuracy of registration, and consequently, enhances the benefit of high-resolution reconstruction. It is also shown that under cases of severe non-uniformity noise, a recursive application of the registration-based NUC may further improve the accuracy of registration and high-resolution image reconstruction. The results are illustrated using real and simulated data. C1 USAF, RL, SNJM, Wright Patterson AFB, OH 45433 USA. RP Armstrong, EE (reprint author), USAF, RL, SNJM, Wright Patterson AFB, OH 45433 USA. NR 30 TC 17 Z9 17 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 0-8194-3294-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3808 BP 150 EP 161 DI 10.1117/12.365831 PG 12 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BN98Z UT WOS:000083768500015 ER PT S AU Senft, DC Fox, MJ Hamilton, CM Richter, DA Higdon, NS Kelly, BT Babnick, RD Pierrottet, DF AF Senft, DC Fox, MJ Hamilton, CM Richter, DA Higdon, NS Kelly, BT Babnick, RD Pierrottet, DF BE SedlacekIII, AJ Fischer, KW TI Ground test results and analysis advancements for the AFRL airborne CO2 DIAL system SO APPLICATIONS OF LIDAR TO CURRENT ATMOSPHERIC TOPICS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Annual Meeting on Applications of Lidar to Current Atmospheric Topics CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE airborne lidar; CO2 DIAL; laser remote sensing; heterodyne DIAL AB The Air Force Research Laboratory (AFRL) Active Remote Sensing Branch has developed the Laser Airborne Remote Sensing (LARS) system for chemical detection using the differential absorption lidar (DIAL) technique. The system is based on a high-power CO2 laser which can use either the standard (CO2)-C-12-O-16 Or the (CO2)-C-13-O-16 carbon dioxide isotopes as the lasing medium, and has output energies of up to 5 J on the stronger laser transitions. The lidar system is mounted on a flight-qualified optical breadboard designed for installation into the AFRL Argus C-135E optical testbed aircraft. The Phase I ground tests were conducted at Kirtland AFB in 1997, prior to the LARS flight tests performed in September 1997 at Kirtland AFB and the Idaho National Engineering and Environmental Laboratory (INEEL). The Phase II ground tests were conducted in 1998 to determine the optimum performance of the LARS system, after the incorporation of modifications and improvements suggested by the night test results. This paper will present some of the chemical detection and radiometric results obtained during the Phase II ground tests. Following the presentation of the direct detection results, a summary of current work on a heterodyne DIAL system is given. C1 USAF, Res Lab, DEBF, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Senft, DC (reprint author), USAF, Res Lab, DEBF, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 5 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 0-8194-3243-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3757 BP 113 EP 125 DI 10.1117/12.366425 PG 13 WC Engineering, Electrical & Electronic; Meteorology & Atmospheric Sciences; Remote Sensing; Optics SC Engineering; Meteorology & Atmospheric Sciences; Remote Sensing; Optics GA BN97U UT WOS:000083736900013 ER PT J AU Viernes, MJL Grimwood, R AF Viernes, MJL Grimwood, R TI Bullous eruption in a 36-year-old man with polycystic kidney disease - Porphyria cutanea tarda (PCT) associated with chronic renal failure. SO ARCHIVES OF DERMATOLOGY LA English DT Article ID VIRUS-INFECTION; HEPATITIS-C; HEMODIALYSIS; ERYTHROPOIETIN C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Viernes, MJL (reprint author), Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0003-987X J9 ARCH DERMATOL JI Arch. Dermatol. PD JAN PY 1999 VL 135 IS 1 BP 81 EP + PG 2 WC Dermatology SC Dermatology GA 158JL UT WOS:000078112200015 ER PT J AU Miller, MD AF Miller, MD TI Untitled - Reply SO ARTHROSCOPY LA English DT Letter C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Miller, MD (reprint author), Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0749-8063 J9 ARTHROSCOPY JI Arthroscopy PD JAN-FEB PY 1999 VL 15 IS 1 BP 116 EP 117 PG 2 WC Orthopedics; Surgery SC Orthopedics; Surgery GA 156KE UT WOS:000077999500021 ER PT S AU Frazier, WG AF Frazier, WG BE Pao, YH LeClair, SR TI Robust fuzzy logic-based control of a hydraulic forge press SO ARTIFICIAL INTELLIGENCE IN REAL-TIME CONTROL 1998 SE IFAC SYMPOSIA SERIES LA English DT Proceedings Paper CT 7th IFAC Symposium on Artificial Intelligence in Real-Time Control CY OCT 05-08, 1998 CL GRAND CANYON NATL PK, AR SP Int Federat Automat Control, USAF, European Off Aerosp Res & Dev, USAF, Res Lab, Case Western Reserve Univ DE fuzzy control; manufacturing systems; hydraulics AB The design of a robust fuzzy logic-based velocity versus stroke control law for a multiple-valve hydraulic forge press is presented. Simulation results illustrating the robustness of the control law are also presented. Copyright (C) 1998 IFAC. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Frazier, WG (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 2 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0962-9505 BN 0-08-043227-1 J9 IFAC SYMP SERIES PY 1999 BP 83 EP 88 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA BP94Y UT WOS:000086709800015 ER PT S AU Hughes, CK Rogers, SK Kabrisky, M Oxley, ME AF Hughes, CK Rogers, SK Kabrisky, M Oxley, ME BE Pao, YH LeClair, SR TI Physiologically-based pattern analysis SO ARTIFICIAL INTELLIGENCE IN REAL-TIME CONTROL 1998 SE IFAC SYMPOSIA SERIES LA English DT Proceedings Paper CT 7th IFAC Symposium on Artificial Intelligence in Real-Time Control CY OCT 05-08, 1998 CL GRAND CANYON NATL PK, AR SP Int Federat Automat Control, USAF, European Off Aerosp Res & Dev, USAF, Res Lab, Case Western Reserve Univ DE human perception; image analysis; visual pattern recognition; models AB The digital computer is a wonderful tool for numeric calculations at incredible speeds, but humans are still vastly superior in pattern recognition and classification of complex visual image patterns. An understanding of how our visual system operates has the potential to inspire us to better, more efficient means of automatic, computer aided pattern analysis of images. Scale, shift and rotations, are easily compensated for within the Human Visual System, and the scene is understood even when presentation is made for the first time. A study of the models for the Human Visual System provides insight into pattern analysis techniques for automatic pattern recognition and classification. Copyright (C) 1998 IFAC. C1 USAF, Res Lab, Mat & Mfg Directorate, MLMR, Wright Patterson AFB, OH 45433 USA. RP Hughes, CK (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLMR, 2977 P St, Wright Patterson AFB, OH 45433 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0962-9505 BN 0-08-043227-1 J9 IFAC SYMP SERIES PY 1999 BP 257 EP 262 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence SC Automation & Control Systems; Computer Science GA BP94Y UT WOS:000086709800043 ER PT J AU Keil, SL Balasubramaniam, KS Smaldone, LA Reger, B AF Keil, SL Balasubramaniam, KS Smaldone, LA Reger, B TI Velocities in solar pores SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : granulation; Sun : magnetic fields; sunspots ID EMERGING FLUX REGION; MAGNETIC-FLUX; SUNSPOTS; ATMOSPHERE; FLOWS; GRANULATION; PHOTOSPHERE; SHIFTS; FIELDS; MODEL AB We use high spatial and spectral resolution filtergrams to examine the three-dimensional morphology and velocity fields associated with solar pores in a region of newly emerged magnetic flux. The observed amplitude of the horizontal surface velocities decreases near the pores, Most of the pores exhibit a downflow in the surrounding region. Time-averaged line-of-sight velocities in and near the pores increased with the strength of the associated magnetic field. The LOS velocities art: such that the maximum downflow is not centered about the continuum intensity and sometimes traces an annulus ringlike structure around the pore. From a time sequence of continuum images, it appears that some pores shed flux at the photospheric level. "Cork movies" of the surface velocities show that the "corks" are advected toward weak downflows near the pore locations and that the loci of the advected corks trace boundaries that resemble mesogranular and supergranular flows. We analyze the vertical velocity structure in pores and show that the downflow decreases exponentially with height, with a scale height that is a factor of 2 smaller than the photospheric scale height for granules. The line-of-sight flow associated with the pores appears to expand with height. Our observations are compared with previous measurements of Bows in and around pores that were based on both spectrograms and filtergrams, Finally, we provide a phenomenological description for pores. C1 Natl Solar Observ, USAF, Res Lab, Sunspot, NM 88349 USA. Sacramento Peak Natl Opt Astron Observ, Natl Solar Observ, Sunspot, NM 88349 USA. Univ Naples Federico 2, Dipartimento Sci Fis, I-80125 Naples, Italy. Northwestern Univ, Dept Mech Engn, Evanston, IL 60208 USA. RP Keil, SL (reprint author), Natl Solar Observ, USAF, Res Lab, Sunspot, NM 88349 USA. NR 47 TC 41 Z9 41 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD JAN 1 PY 1999 VL 510 IS 1 BP 422 EP 443 DI 10.1086/306549 PN 1 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 176NG UT WOS:000079157400036 ER PT B AU Shipman, RF Egan, MP Price, SD Kuchar, TA Carey, SJ AF Shipman, RF Egan, MP Price, SD Kuchar, TA Carey, SJ BE Bicay, M Beichman, CA Cutri, RM Madore, BF TI MSX observations of the Galactic Center SO ASTROPHYSICS WITH INFRARED SURVEYS: A PRELUDE TO SIRTF SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Astrophysics with Infrared Surveys - A Prelude to SIRTF CY JUN 22-24, 1998 CL CALIFORNIA INST TECHNOL, PASADENA, CA SP NASA Off Space Sci, SIRTR Sci Ctr, Infrared Processing & Anal Ctr, Caltech Off Public Events, SIRTF Project Off JPL, Lockheed Martin Missiles & Space, Ball Aerosp Technol Corp HO CALIFORNIA INST TECHNOL ID MIDCOURSE SPACE EXPERIMENT AB We present 8.3, 12.1, 14.7, and 21.4 mu m images of a 4 by 2 degree region around the Galactic Center obtained by the SPIRIT III infrared radiometer onboard the Midcourse Space Experiment (MSX; Mill et al. 1994). The images are co-added from 5 scans of the Galactic Plane survey (Price 1995) to improve the sensitivity and coverage of the region over previously presented images (Shipman, Egan, & Price 1996). The images display the large scale distribution of dust and stars around the center at a spatial resolution of 18 arcseconds. We present SPIRIT III measurements of a wide range of objects associated with the Galactic Center: the thermal radio area, Sgr B, Sgr D and Sgr A environments. C1 USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. RP Shipman, RF (reprint author), USAF, Res Lab, VSBC, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-001-3 J9 ASTR SOC P PY 1999 VL 177 BP 314 EP 317 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89F UT WOS:000083362400046 ER PT B AU Shipman, RF Egan, MP Price, SD Kuchar, TA Carey, SJ AF Shipman, RF Egan, MP Price, SD Kuchar, TA Carey, SJ BE Bicay, M Beichman, CA Cutri, RM Madore, BF TI MSX views of star forming regions SO ASTROPHYSICS WITH INFRARED SURVEYS: A PRELUDE TO SIRTF SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Astrophysics with Infrared Surveys - A Prelude to SIRTF CY JUN 22-24, 1998 CL CALIFORNIA INST TECHNOL, PASADENA, CA SP NASA Off Space Sci, SIRTR Sci Ctr, Infrared Processing & Anal Ctr, Caltech Off Public Events, SIRTF Project Off JPL, Lockheed Martin Missiles & Space, Ball Aerosp Technol Corp HO CALIFORNIA INST TECHNOL ID MIDCOURSE SPACE EXPERIMENT; ROSETTE NEBULA; GLOBULES AB We present mid IR, co-added images of four star forming regions observed with the SPIRIT III radiometer on the Midcourse Space Experiment (MSX). The observations cover areas 1 degrees to 6 degrees on a side at a spatial resolution of 18". The objects considered in this poster are : The Orion Molecular Cloud, the Rosette Nebula Chamaeleon, and the Taurus molecular cloud. C1 USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. RP Shipman, RF (reprint author), USAF, Res Lab, VSBC, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-001-3 J9 ASTR SOC P PY 1999 VL 177 BP 318 EP 321 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89F UT WOS:000083362400047 ER PT B AU Price, SD Egan, MP Shipman, RF AF Price, SD Egan, MP Shipman, RF BE Bicay, M Beichman, CA Cutri, RM Madore, BF TI The Midcourse Space Experiment SO ASTROPHYSICS WITH INFRARED SURVEYS: A PRELUDE TO SIRTF SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Astrophysics with Infrared Surveys - A Prelude to SIRTF CY JUN 22-24, 1998 CL CALIFORNIA INST TECHNOL, PASADENA, CA SP NASA Off Space Sci, SIRTR Sci Ctr, Infrared Processing & Anal Ctr, Caltech Off Public Events, SIRTF Project Off JPL, Lockheed Martin Missiles & Space, Ball Aerosp Technol Corp HO CALIFORNIA INST TECHNOL ID IRAS AB The Midcourse Space Experiment completed the census of the mid-infrared sky, surveying the areas that IRAS either missed or covered with degraded sensitivity. The MSX surveys include the 4% of the inertial sky missed by IRAS, sampling of the zodiacal background over a much greater range of solar elongations and a survey within 5 degrees of the Galactic Plane. The 18.3" MSX pixels resolve much of the high source density regions and structured emission along the Galactic Plane and certain selected regions, such as the Magellanic Clouds. MSX is able to probe six times fainter than IRAS in the regions of highest source densities. C1 USAF, Res Lab, VSBC, Washington, DC 20330 USA. RP Price, SD (reprint author), USAF, Res Lab, VSBC, Washington, DC 20330 USA. NR 5 TC 10 Z9 10 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-001-3 J9 ASTR SOC P PY 1999 VL 177 BP 394 EP 403 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89F UT WOS:000083362400062 ER PT B AU Egan, MP Price, SD Shipman, RF Gugliotti, GM Tedesco, EF Moshir, M Cohen, M AF Egan, MP Price, SD Shipman, RF Gugliotti, GM Tedesco, EF Moshir, M Cohen, M BE Bicay, M Beichman, CA Cutri, RM Madore, BF TI The MSX Infrared Point Source Catalog, version 1.0 SO ASTROPHYSICS WITH INFRARED SURVEYS: A PRELUDE TO SIRTF SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Conference on Astrophysics with Infrared Surveys - A Prelude to SIRTF CY JUN 22-24, 1998 CL CALIFORNIA INST TECHNOL, PASADENA, CA SP NASA Off Space Sci, SIRTR Sci Ctr, Infrared Processing & Anal Ctr, Caltech Off Public Events, SIRTF Project Off JPL, Lockheed Martin Missiles & Space, Ball Aerosp Technol Corp HO CALIFORNIA INST TECHNOL AB The forthcoming MSX Infrared Point Source Catalog completes the infrared census of the sky near the galactic plane, where the IRAS survey was confusion limited, and in the 4% of sky not surveyed by IRAS. The MSX infrared detectors have approximately 35 times the resolution of IRAS. The MSX galactic plane survey can achieve a source density of (similar to)400 sources per square degree, compared to the (similar to)40 sources per square degree from IRAS. This paper describes the techniques used to construct the MSX catalog and presents preliminary analyses of the source statistics. C1 USAF, Res Lab, Washington, DC 20330 USA. RP Egan, MP (reprint author), USAF, Res Lab, Washington, DC 20330 USA. NR 2 TC 15 Z9 15 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-001-3 J9 ASTR SOC P PY 1999 VL 177 BP 404 EP 408 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89F UT WOS:000083362400063 ER PT J AU Strakey, PA Talley, DG AF Strakey, PA Talley, DG TI The effect of manifold cross-flow on the discharge coefficient of sharp-edged orifices SO ATOMIZATION AND SPRAYS LA English DT Article AB The objective of this study is to determine the effect of manifold cross-flow on the discharge coefficient and cavitation characteristics of sharp-edged orifices over a wide range of flow rates, back pressures, and cross-flow velocities. The geometries studied cover a range of orifice diameters, length-to-diameter ratios, and orifice angles characteristic of impinging-element liquid rocket injectors. Experimental results for an orifice angle of 90 degrees with respect to the manifold are presented. Along with the experimental effort, an analytical model has been developed. The model predicts the discharge coefficient for a sharp-edged orifice over a wide range of flow regimes including cavitating and noncavitating flow, and for a wide range of orifice geometries. The analytical model generally shows good agreement with the experimental data over the range of conditions studied here. The model also closely follows the experimental data for cavitating flow except when the orifice length-to-diameter ratio is small, in which case the model overpredicts the discharge coefficient. C1 USAF, Res Lab, Edwards AFB, CA 93523 USA. RP Strakey, PA (reprint author), USAF, Res Lab, Edwards AFB, CA 93523 USA. NR 13 TC 9 Z9 9 U1 1 U2 1 PU BEGELL HOUSE INC PI NEW YORK PA 79 MADISON AVE, SUITE 1205, NEW YORK, NY 10016-7892 USA SN 1044-5110 J9 ATOMIZATION SPRAY JI Atom. Sprays PD JAN-FEB PY 1999 VL 9 IS 1 BP 51 EP 68 PG 18 WC Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 157AT UT WOS:000078037200003 ER PT B AU Siouris, GM AF Siouris, GM BE Lee, JG TI Flight control technology: An overview SO AUTOMATIC CONTROL IN AEROSPACE 1998 LA English DT Proceedings Paper CT 14th IFAC Symposium on Automatic Control in Aerospace 1998 CY AUG 24-28, 1998 CL SEOUL, SOUTH KOREA SP Int Federat Automat Control, Tech Comm Aerosp, Seoul Natl Univ, Automat Control Res Ctr, Korea Aerosp Res Inst DE flight control; autopilot; stability; hierarchical Kalman filter; situational awareness; belief network; flight management computer system AB Over the past twenty years, the spectrum of flight control technology has greatly expanded from the original concept of mechanical control linkages and autopilots to one of multidisciplinary control integration technology. Control integration now exerts a major influence on aircraft design, air combat effectiveness, and aircraft survivability. Flight control functions as the information manager and nerve center between the pilot-and the vehicle optimizing the aircraft's controllability, performance, safety, and mission effectiveness. This paper will discuss present and future flight control technologies, with emphasis in the pilot-vehicle interface. Moreover, modem flight control technologies will have a major impact on a broad class, not only of current manned aircraft, missiles, and space vehicles, but through the year 2000 and beyond. (C) 1998 IFAC. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Siouris, GM (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 8 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-08-043041-4 PY 1999 BP 283 EP 288 PG 6 WC Automation & Control Systems; Engineering, Aerospace SC Automation & Control Systems; Engineering GA BN30F UT WOS:000081459200041 ER PT S AU Alsing, SG Blasch, EP Bauer, KW AF Alsing, SG Blasch, EP Bauer, KW BE Sadjadi, FA TI Three-dimensional (3-D) receiver operating characteristic (ROC) trajectory concepts for the evaluation of target recognition algorithms faced with the unknown target detection problem SO AUTOMATIC TARGET RECOGNITION IX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 9th Conference on Automatic Target Recognition CY APR 07-09, 1999 CL ORLANDO, FL SP SPIE DE receiver operating characteristic (ROC); automatic target recognition (ATR); performance; rejection AB This paper presents a three-dimensional (3-D) receiver operating characteristic (ROC) trajectory which combines the principles of the standard ROC curve used in automatic target recognition (ATR) with a third performance measure. These 3-D ROC trajectories are used to compare competing target recognition algorithms when unknown targets are present in the data. A probability of rejection is added to the standard ROC curve that includes the probability of successful detection (true positive rate) and the probability of false alarm (false positive rate). By using the probability of rejection, targets may be eliminated that are difficult to classify, or perhaps unknown. The 3-D ROC trajectory can be a useful tool for a SAR image analyst for understanding the tradeoffs between the probability of rejection and the two standard performance measures commonly used in detection problems. C1 USAF, Inst Technol, Dept Operat Sci, Wright Patterson AFB, OH 45433 USA. RP Alsing, SG (reprint author), USAF, Inst Technol, Dept Operat Sci, Wright Patterson AFB, OH 45433 USA. NR 16 TC 10 Z9 10 U1 0 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3192-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3718 BP 449 EP 458 DI 10.1117/12.359981 PG 10 WC Engineering, Aerospace SC Engineering GA BN77Q UT WOS:000082902000046 ER PT J AU Kiel, JL Seaman, RL Mathur, SP Parker, JE Wright, JR Alls, JL Morales, PJ AF Kiel, JL Seaman, RL Mathur, SP Parker, JE Wright, JR Alls, JL Morales, PJ TI Pulsed microwave induced light, sound, and electrical discharge enhanced by a biopolymer SO BIOELECTROMAGNETICS LA English DT Article DE radio frequency radiation; diazoluminomelanin; free radicals ID SONOLUMINESCENCE; LUMINOL AB Intense flashes of light were observed in sodium bicarbonate and hydrogen peroxide solutions when they were exposed to pulsed microwave radiation, and the response was greatly enhanced by a microwave-absorbing, biosynthesized polymer, diazoluminomelanin. A FPS-7B radar transmitter, operating at 1.25 GHz provided pulses of 5.73 +/- 0.09 mu s in duration at 10.00 +/- 0.03 pulses/s with 2.07 +/- 0.08 MW forward power (mean +/- standard deviation), induced the effect but only when the appropriate chemical interaction was present. This phenomenon involves acoustic wave generation, bubble formation, pulsed luminescence, ionized gas ejection, and electrical discharge. The use of pulsed microwave radiation to generate highly focused energy deposition opens up the possibility of a variety of biomedical applications, including targeting killing of microbes or eukaryotic cells. The full range of microwave intensities and frequencies that induce these effects has yet to be explored and, therefore, the health and safety implications of generating the phenomena in living tissues remain an open question. Published 1999 Wiiey-Liss, Inc.(dagger) C1 USAF, HEDB, Res Lab, Directed Energy Bioeffects Div, Brooks AFB, TX 78235 USA. McKesson BioServ, Brooks AFB, TX USA. USA, Med Res Detachment, Brooks AFB, TX USA. SE Oklahoma State Univ, Dept Phys Sci, Durant, OK USA. RP Kiel, JL (reprint author), USAF, HEDB, Res Lab, Directed Energy Bioeffects Div, 2503 Gillingham Dr,Bldg 175E, Brooks AFB, TX 78235 USA. NR 13 TC 5 Z9 5 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1999 VL 20 IS 4 BP 216 EP 223 DI 10.1002/(SICI)1521-186X(1999)20:4<216::AID-BEM2>3.0.CO;2-8 PG 8 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA 187FC UT WOS:000079775400002 PM 10230935 ER PT J AU Jauchem, JR Ryan, KL Frei, MR AF Jauchem, JR Ryan, KL Frei, MR TI Cardiovascular and thermal responses in Rats during 94 GHz irradiation SO BIOELECTROMAGNETICS LA English DT Article DE microwaves; heart rate; blood pressure; millimeter waves ID LETHAL HEAT-STRESS; CIRCULATORY FAILURE; RADIOFREQUENCY IRRADIATION AB We investigated the thermal distribution and cardiovascular effects produced by sustained exposure of rats to 94 GHz radio-frequency electromagnetic radiation (RFR). Sixteen ketamine-anesthetized Sprague-Dawley rats were exposed individually at a power density of 75 mW/cm(2) under far-field conditions in E orientation. Irradiation began when colonic temperature was 37 degrees C and continued until death. Large, immediate increases in subcutaneous temperature on the irradiated side were accompanied by more moderate, delayed increases in colonic temperature. These body-temperature responses were similar to previous results obtained during 35 GHz RFR exposure. During irradiation, arterial blood pressure initially increased and then precipitously decreased until death. The heart rate increased throughout the exposure period. When comparing the results of these 94 GHz exposures with those in previous studies of lower RFR frequencies, it appears that the patterns of heart-rate and blood-pressure changes that occur before death are similar. We conclude that exposure to 94 GHz RFR produces extreme peripheral heating without similar levels of core heating and that this pattern of heat deposition is sufficient to produce circulatory failure and subsequent death. Published 1999 Wiley-Liss, Inc.(dagger) C1 USAF, HEDR, Res Lab,Radio Frequency Radiat Branch, Human Effectiveness Directorate,Directed Energy B, Brooks AFB, TX 78235 USA. Trinity Univ, Dept Biol, San Antonio, TX 78212 USA. RP Jauchem, JR (reprint author), USAF, HEDR, Res Lab,Radio Frequency Radiat Branch, Human Effectiveness Directorate,Directed Energy B, 8308 Hawks Rd, Brooks AFB, TX 78235 USA. EM james.jauchem@aloer.brooks.af.mil NR 22 TC 10 Z9 12 U1 1 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1999 VL 20 IS 4 BP 264 EP 267 PG 4 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA 187FC UT WOS:000079775400007 PM 10230940 ER PT J AU Miller, SA Bronson, ME Murphy, MR AF Miller, SA Bronson, ME Murphy, MR TI Ultrawideband radiation and pentylenetetrazol-induced convulsions in rats SO BIOELECTROMAGNETICS LA English DT Article DE PTZ; seizures; ultrashort pulse width; fast-rise-time; tissue damage; non-ionizing radiation ID PULSES; EXPOSURE AB New non-ionizing pulsed systems using ultrawideband (UWB) require safety assessment before they can be used by either military or civilian communities. Tnt: development of directed energy weaponry intended for use against electronically vulnerable targets, as well as ground-probing radar systems, have used fast-rise-time high-peak-power electromagnetic pubes characteristic of UWB emitters. It has been postulated that these ultrashort pulses might produce electromagnetic transients resulting in tissue damage. Several challenges to this notion have been posed, however. One report found that rats exposed to UWB after receiving a convulsant drug tended toward longer latency to the onset of convulsions than the no-exposure group. Although not statistically significant, the presence of this trend prompted the present study. An ED,, dose of the convulsant pentylenetetrazol (PTZ) or saline was given just before UWB or sham exposure and resultant seizure activity was recorded. The data from the current study show no effect of UWB exposure on PTZ-induced seizure activity, thereby not supporting the tissue damage concerns, at least for the exposure parameters used here. Published 1999 Wiley-Liss, Inc.dagger. C1 USAF, RL, HEDR,Radio Frequency Radiat Branch, Directed Energy Bioeffects Div, Brooks AFB, TX 78235 USA. Wilkes Univ, Sch Pharm, Dept Pharmaceut Sci, Wilkes Barre, PA 18766 USA. RP Miller, SA (reprint author), USAF, RL, HEDR,Radio Frequency Radiat Branch, Directed Energy Bioeffects Div, 8315 Hawks Rd,Bldg 1162, Brooks AFB, TX 78235 USA. NR 12 TC 10 Z9 10 U1 0 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1999 VL 20 IS 5 BP 327 EP 329 DI 10.1002/(SICI)1521-186X(1999)20:5<327::AID-BEM9>3.0.CO;2-E PG 3 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA 211VR UT WOS:000081183000008 PM 10407518 ER PT J AU Adair, ER Cobb, BL Mylacraine, KS Kelleher, SA AF Adair, ER Cobb, BL Mylacraine, KS Kelleher, SA TI Human exposure at two radio frequencies (450 and 2450 MHz): Similarities and differences in physiological response SO BIOELECTROMAGNETICS LA English DT Article; Proceedings Paper CT Symposium RF Dosimetry - 25 Years of Progress CY OCT 20-21, 1997 CL SALT LAKE CITY, UT SP USAF Armstrong Lab DE thermoregulation; metabolic rate; sweating; skin blood flow; body temperature; microwaves ID ABSORPTION; ENERGY; SAR AB Thermoregulatory responses of heat production and heat loss were measured in two different groups of seven adult volunteers (males and females) during 45-min dorsal exposures of the whole body to 450 or 2450 MHz continuous-wave radio frequency (RF) fields. At each frequency, two power densities (PD) were tested at each of three ambient temperatures (T(a) = 24, 28, and 31 degrees C) plus T(a) controls (no RP). The normalized peak surface specific absorption rate (SAR), measured at the location of the subject's center back, was the same for comparable PD at both frequencies, i.e., peak surface SAR = 6.0 and 7.7 W/kg. No change in metabolic heat production occurred under any exposure conditions at either frequency. The magnitude of increase in those skin temperatures under direct irradiation was directly related to frequency, but local sweating rates on back and chest were related more to T(a) and SAR. Both efficient sweating and increased local skin blood flow contributed to the regulation of the deep body (esophageal) temperature to within 0.1 degrees C of the baseline level. At both frequencies, normalized peak SARs in excess of ANSI/IEEE C95.1 guidelines were easily counteracted by normal thermophysiological mechanisms. The observed frequency-related response differences agree with classical data concerning the control of heat loss mechanisms in human beings. However, more practical dosimetry than is currently available will be necessary to evaluate realistic human exposures to RF energy in the natural environment. Bioelectromagnetics 20:12-20, 1999. Published 1999 Wiley-Liss, Inc.dagger. C1 USAF, Res Lab, HEDR, Brooks AFB, TX 78235 USA. Veridian Inc, Brooks AFB, TX USA. John B Pierce Fdn Lab, New Haven, CT 06519 USA. RP Adair, ER (reprint author), USAF, Res Lab, HEDR, 8308 Hawks Rd, Brooks AFB, TX 78235 USA. EM eleanor.adair@aloer.broods.af.mil NR 27 TC 5 Z9 5 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1999 SU 4 BP 12 EP 20 PG 9 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA 183QB UT WOS:000079564000004 ER PT J AU Kiel, JL Alls, JL Mason, PA Erwin, DN AF Kiel, JL Alls, JL Mason, PA Erwin, DN TI Luminescent radio frequency radiation dosimetry SO BIOELECTROMAGNETICS LA English DT Article; Proceedings Paper CT Symposium RF Dosimetry - 25 Years of Progress CY OCT 20-21, 1997 CL SALT LAKE CITY, UT SP USAF Armstrong Lab DE diazoluminomelanin; thermochemiluminescence; microwaves; mm waves AB Thermoluminescent dosimetry has been the industry standard for ionizing radiation dosimetry because it is inexpensive, sensitive, and accurate. No such system exists for radio frequency radiation. This paper describes the state of the art of efforts toward developing such a system. Thermochemiluminescent (TCL) dosimetry, first reported in 1991, is a first step toward achieving this goal. However, it has had problems in the production of TCL materials and in conversion of the luminescent signal into specific absorption rate (SAR). The former problem has been solved by the development of a genetically engineered Escherichia coli bacterium (JM 1091plC20RNR(1.1)), described herein, that produces the TCL material in a fermentation process. The latter problem stems from the difficulty in determining the structure of the currently best TCL material diazoluminomelanin. A theoretical approach for the solution of this problem has been achieved by combining equations for delayed fluorescence, temperature determination by TCL, and the free energy equation for equilibrium reactions. It has led to an explanation for the stable display of steady-state energy disposition, illustrated by TCL, in phantoms without the expected disruption by thermal conduction or convection, at frequencies ranging from 2.06 GHz to 35 GHz. Bioelectromagnetics 20:46-51, 1999. Published 1999 Wiley-Liss, Inc.dagger. C1 USAF, Res Lab, Directed Energy Bioeffects Div, Brooks AFB, TX 78235 USA. Veridian Inc, San Antonio, TX USA. Occupat & Environm Hlth Inst, Human Syst Ctr, Brooks AFB, TX USA. RP Kiel, JL (reprint author), USAF, Res Lab, Directed Energy Bioeffects Div, Brooks AFB, TX 78235 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1999 SU 4 BP 46 EP 51 PG 6 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA 183QB UT WOS:000079564000007 ER PT B AU Spain, JC Nishino, SF Greene, MR Forbort, JE Nogalski, NA Unterman, R Riznychok, WM Thompson, SE Sleeper, PM Boxwell, MA AF Spain, JC Nishino, SF Greene, MR Forbort, JE Nogalski, NA Unterman, R Riznychok, WM Thompson, SE Sleeper, PM Boxwell, MA BE Alleman, BC Leeson, A TI Field demonstration of FBR for treatment of nitrotoluenes in groundwater SO BIOREMEDIATION OF NITROAROMATIC AND HALOAROMATIC COMPOUNDS LA English DT Proceedings Paper CT 5th International In Situ and On-Site Bioremediation Symposium CY APR 19-22, 1999 CL SAN DIEGO, CA SP Battelle Mem Inst, Gas Res Inst, IT Grp Inc, Celtic Technol, Parsons Engn Sci Inc, U S Microb Inc, U S Naval Fac Engn Command, Waste Management Inc ID SP STRAIN DNT; PSEUDOMONAS-SP; 2,4-DINITROTOLUENE; BIODEGRADATION; DEGRADATION; BIOREACTOR AB A pilot-scale field demonstration was conducted to collect reliable cost and performance data for an aerobic, biological fluidized bed reactor (FBR) system that treats groundwater contaminated with nitrotoluenes. This project is an extension of a previous bench-scale FBR study on the simultaneous degradation of 2,4- and 2,6-dinitrotoluene. The FBR was inoculated with a mixed culture of bacteria that had been acclimated to a mixture of mono- and dinitrotoluenes. The contaminated groundwater was drawn from wells at the Volunteer Army Ammunition Plant (VAAP) in Chattanooga, TN. The nitrotoluene (NT) contaminants identified in the groundwater and their typical concentrations were: 2,4,6-trinitrotoluene (2,4,6-TNT) at 1.1 mg/L, 2,4-dinitrotoluene (2,4-DNT) at 9.2 mg/L, 2,6-dinitrotoluene (2,6-DNT) at 8.6 mg/L, 2-nitrotoluene (2-NT) at 2.9 mg/L, 3-nitrotoluene (3-NT) at 0.4 mg/L, and 4-nitrotoluene (4-NT) at 3.0 mg/L. A range of loading rates and a variety of operating conditions were used to evaluate the FBR performance. The COD and NT loading rates, based on the volume of the fluidized bed, ranged from 0.6-11 kg COD/m(3)/d and 0.45-4.5 kg NT/m(3)/d. The best FBR performance was measured at the lower loading rates; a 96% reduction in NT and 93% reduction in COD were found at a loading rate of 1.0 kg NT/m(3)/d (2.2 kg COD/m(3)/d). The effluent at this loading rate contained an average of 0.5 mg 2,4,6-TNT and 0.8 mg 2,6-DNT per liter. The other NT compounds were below detection levels (0.05 mg/L). At the highest steady loading rate, 3.5 kg NT/m(3)/d (7.6 kg COD/m(3)/d), a 62% reduction in NT and 49% reduction in COD were measured. The effluent at this loading contained an average of 0.8 mg/L 2,4,6-TNT, 7.0 mg/L 2,6-DNT and 1.3 mg/L 2,4-DNT. The mononitrotoluenes were still below detection levels at the highest loading rate. Therefore, this FBR process can effectively remove mono- and dinitrotoluenes from contaminated groundwater, and at appropriate loading rates the FBR process is cost-effective compared to alternative technologies. C1 USA, Armstrong Lab, Tyndall AFB, FL USA. RP Spain, JC (reprint author), USA, Armstrong Lab, Tyndall AFB, FL USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-080-2 PY 1999 BP 7 EP 14 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA BN63D UT WOS:000082417000002 ER PT J AU Grace, MS Church, DR Kelly, CT Lynn, WF Cooper, TM AF Grace, MS Church, DR Kelly, CT Lynn, WF Cooper, TM TI The Python pit organ: imaging and immunocytochemical analysis of an extremely sensitive natural infrared detector SO BIOSENSORS & BIOELECTRONICS LA English DT Article; Proceedings Paper CT 5th World Congress on Biosensors CY JUN 03-05, 1998 CL BERLIN, GERMANY DE infrared; imaging; detector; photoreceptor; snake; calcium-binding proteins AB The Python infrared-sensitive pit organ is a natural infrared imager that combines high sensitivity, ambient temperature function, microscopic dimensions, and self-repair. We are investigating the spectral sensitivity and signal transduction process in snake infrared-sensitive neurons, neither of which is understood. For example, it is unknown whether infrared receptor neurons function on a thermal or a photic mechanism. We imaged pit organs in living Python molurus and Python regius using infrared-sensitive digital video cameras. Pit organs were significantly more absorptive and/or emissive than surrounding tissues in both 3-5 mu m and 8-12 mu m wavelength ranges, Pit organs exhibited greater absorption/emissivity in the 8-12 mu m range than in the 3-5 mu m range. To directly test the relationship between photoreceptors and pit organ infrared-sensitive neurons, we performed immunocytochemistry using antisera directed against retinal photoreceptor opsins. Retinal photoreceptors were labeled with antisera specific for retinal opsins, but these antisera failed to label terminals of infrared-sensitive neurons in the pit organ. Infrared-receptive neurons were also distinguished from retinal photoreceptors on the basis of their calcium-binding protein content. These results indicate that the pit organ absorbs infrared radiation in two major atmospheric transmission windows, one of which (8-12 mu m) matches emission of targeted prey, and that infrared receptors are biochemically distinct from retinal photoreceptors. These results also provide the first identification of prospective biochemical components of infrared signal transduction in pit organ receptor neurons. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Univ Virginia, Dept Biol, Charlottesville, VA 22903 USA. Wright State Univ, Dept Biomed Engn, Dayton, OH 45435 USA. Syst Res Labs, Dayton, OH USA. Wright Lab, MLPJ, Wright Patterson AFB, OH USA. RP Grace, MS (reprint author), Univ Virginia, Dept Biol, Gilmer Hall, Charlottesville, VA 22903 USA. EM msg5y@virginia.edu NR 18 TC 19 Z9 20 U1 1 U2 5 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0956-5663 J9 BIOSENS BIOELECTRON JI Biosens. Bioelectron. PD JAN 1 PY 1999 VL 14 IS 1 BP 53 EP 59 DI 10.1016/S0956-5663(98)00101-8 PG 7 WC Biophysics; Biotechnology & Applied Microbiology; Chemistry, Analytical; Electrochemistry; Nanoscience & Nanotechnology SC Biophysics; Biotechnology & Applied Microbiology; Chemistry; Electrochemistry; Science & Technology - Other Topics GA 160JP UT WOS:000078227100007 PM 10028649 ER PT S AU Lawton, JH Turner, RM Turner, EH AF Lawton, JH Turner, RM Turner, EH BE Althoff, KD Bergmann, R Branting, LK TI A Unified Long-Term Memory system SO CASE-BASED REASONING RESEARCH AND DEVELOPMENT SE LECTURE NOTES IN ARTIFICIAL INTELLIGENCE LA English DT Article; Proceedings Paper CT 3rd International Conference on Case-Based Reasoning (ICCBR-99) CY JUL 27-30, 1999 CL SEEON MONASTERY, GERMANY SP German Soc Comp Sci, Amer Assoc Artificial Intelligence, AcknoSoft, BSR Consulting, DaimlerChrysler, Fraunhofer Inst Exptl Software Engn, Inference Syst, Fraunhofer Inst Exptl Software Engn, Interact Multimedia Syst, Univ Kaiserslautern, Univ Wyoming AB Memory-based reasoning systems are a class of reasoners that derive solutions to new problems based on past experiences. Such reasoners use a long-term memory (LTM) to act as a knowledge base of these past experiences, which may be represented by such things as specific events (i.e, cases), plans, scripts, etc. This paper describes a Unified Long-Term Memory (ULTM) system, which is a dynamic, conceptual memory that was designed to be a general LTM capable of simultaneously supporting multiple intentional reasoning systems. Through a unique mixture of content-independent and domain-specific mechanisms, the ULTM is able to flexibly provide reasoners accurate and timely storage and recall of episodic memory structures. In addition, the ULTM provides support for recognizing opportunities to satisfy suspended goals, allowing reasoning systems to better cope with the unpredictability of dynamic real-world domains by helping them take advantage of unexpected events. C1 USAF, Res Lab, Griffiss AFB, NY 13441 USA. Univ Maine, Dept Comp Sci, Orono, ME 04469 USA. RP Lawton, JH (reprint author), USAF, Res Lab, Rome Res Site, Griffiss AFB, NY 13441 USA. NR 18 TC 0 Z9 0 U1 1 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-66237-5 J9 LECT NOTES ARTIF INT PY 1999 VL 1650 BP 188 EP 202 PG 15 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Computer Science GA BP13D UT WOS:000084209300014 ER PT B AU Fugate, RQ AF Fugate, RQ BE Restaino, SR Junor, W Duric, N TI Adaptive optics for the 21(st) century SO CATCHING THE PERFECT WAVE: ADAPTIVE OPTICS AND INTERFEROMETRY IN THE 21ST CENTURY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on Catching the Perfect Wave - Adaptive Optics and Interferometry in the 21st-Century held at the 110th Annual Astronomical-Society-of-the-Pacific CY JUN 28-JUL 01, 1998 CL ALBUQUERQUE, NM SP Astron Soc Pacific ID PERFORMANCE; SYSTEMS AB Adaptive optics is an enabling technology for large aperture ground-based telescopes and interferometric arrays that breaks the angular resolution barrier set by atmospheric turbulence. This paper discusses some of the important trends of this technology and how it might impact astronomy in the early part of the next century. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Fugate, RQ (reprint author), USAF, Res Lab, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 14 TC 2 Z9 2 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-96-1 J9 ASTR SOC P PY 1999 VL 174 BP 55 EP 67 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89A UT WOS:000083350300008 ER PT B AU Drummond, J Christou, J Spillar, E AF Drummond, J Christou, J Spillar, E BE Restaino, SR Junor, W Duric, N TI Measuring binaries with the starfire optical range 3.5-meter telescope SO CATCHING THE PERFECT WAVE: ADAPTIVE OPTICS AND INTERFEROMETRY IN THE 21ST CENTURY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on Catching the Perfect Wave - Adaptive Optics and Interferometry in the 21st-Century held at the 110th Annual Astronomical-Society-of-the-Pacific CY JUN 28-JUL 01, 1998 CL ALBUQUERQUE, NM SP Astron Soc Pacific ID SPECKLE INTERFEROMETRY; IMAGES; ORBITS AB We report on imaging of four binary stars using the adaptive optics system of the AFRL SOR 3.5m telescope under poor seeing conditions. We show that although the point spread functions of individual 200ms frames fluctuate, accurate positions and relative magnitudes can be obtained. We use this data to refine the orbits of the binary stars. C1 USAF, Res Lab, Starfire Opt Range, AFRL DES 3550, Kirtland AFB, NM 87117 USA. RP Drummond, J (reprint author), USAF, Res Lab, Starfire Opt Range, AFRL DES 3550, Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-96-1 J9 ASTR SOC P PY 1999 VL 174 BP 125 EP 129 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89A UT WOS:000083350300016 ER PT B AU Sanchez, DJ AF Sanchez, DJ BE Restaino, SR Junor, W Duric, N TI Calculation of the noise induced bias in the complex visibility SO CATCHING THE PERFECT WAVE: ADAPTIVE OPTICS AND INTERFEROMETRY IN THE 21ST CENTURY SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT Symposium on Catching the Perfect Wave - Adaptive Optics and Interferometry in the 21st-Century held at the 110th Annual Astronomical-Society-of-the-Pacific CY JUN 28-JUL 01, 1998 CL ALBUQUERQUE, NM SP Astron Soc Pacific ID OPTICAL SYNTHESIS IMAGES; INTERFEROMETER AB The noise induced bias, that is, the degradations in the complex visibility due to variations in coherence caused by optical path difference fluctuations, inter-pupil intensity fluctuations, and finite spectral bandwidths are calculated. From this and for a given noise source, variations in the complex visibility are shown to be different for an aligned optical system than for a misaligned optical system. C1 USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 USA. RP Sanchez, DJ (reprint author), USAF, Res Lab, DEBS, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-96-1 J9 ASTR SOC P PY 1999 VL 174 BP 159 EP 166 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN89A UT WOS:000083350300020 ER PT J AU Gu, GX Sparks, A Belta, C AF Gu, GX Sparks, A Belta, C TI Stability analysis for rotating stall dynamics in axial flow compressors SO CIRCUITS SYSTEMS AND SIGNAL PROCESSING LA English DT Article; Proceedings Paper CT 37th IEEE Conference on Decision and Control CY DEC 16-18, 1998 CL TAMPA, FL SP IEEE Control Syst Soc, Soc Ind & Appl Math, Inst Operat Res & Management Sci ID SYSTEMS AB This paper analyzes the nonlinear phenomenon of rotating stall via the methods of projection [Elementary Stability and Bifurcation Theory, G. Iooss and D. D. Joseph, Springer-Verlag, 1980] and Lyapunov [J.-H. Fu, Math. Control Signal Systems, 7, 255-278, 1994]. A compressor model of Moore and Greitzer is adopted in which rotating stall dynamics are associated with Hopf bifurcations. Local stability for each pair of the critical modes is studied and characterized. It is shown that local stability of individual pairs of the critical modes determines collectively local stability of the compressor model. Explicit conditions are obtained for local stability of rotating stall which offer new insight into the design, and active control of axial flow compressors. C1 Louisiana State Univ, Dept Elect & Comp Engn, Baton Rouge, LA 70803 USA. USAF, Wright Lab, Flihgt Dynam Directorate, Wright Patterson AFB, OH 45433 USA. RP Gu, GX (reprint author), Louisiana State Univ, Dept Elect & Comp Engn, Baton Rouge, LA 70803 USA. EM ggu@ee.lsu.edu NR 10 TC 1 Z9 1 U1 0 U2 2 PU BIRKHAUSER BOSTON INC PI CAMBRIDGE PA 675 MASSACHUSETTS AVE, CAMBRIDGE, MA 02139 USA SN 0278-081X J9 CIRC SYST SIGNAL PR JI Circuits Syst. Signal Process. PY 1999 VL 18 IS 4 BP 331 EP 350 DI 10.1007/BF01200786 PG 20 WC Engineering, Electrical & Electronic SC Engineering GA 239GK UT WOS:000082760300002 ER PT J AU Harner, CD Miller, MD AF Harner, CD Miller, MD TI Preface SO CLINICS IN SPORTS MEDICINE LA English DT Editorial Material C1 Univ Pittsburgh, Dept Orthopaed Surg, Div Sports Med, Ctr Sports Med & Rehabil, Pittsburgh, PA 15213 USA. Wilford Hall USAF Med Ctr, USHS Dept Orthopaed, Lackland AFB, TX 78236 USA. RP Harner, CD (reprint author), Univ Pittsburgh, Dept Orthopaed Surg, Div Sports Med, Ctr Sports Med & Rehabil, 4601 Baum Blvd, Pittsburgh, PA 15213 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0278-5919 J9 CLIN SPORT MED JI Clin. Sports Med. PD JAN PY 1999 VL 18 IS 1 BP XI EP XII DI 10.1016/S0278-5919(05)70126-5 PG 2 WC Sport Sciences SC Sport Sciences GA 160HC UT WOS:000078223600001 ER PT J AU Rispoli, DM Miller, MD AF Rispoli, DM Miller, MD TI Options in meniscal repair SO CLINICS IN SPORTS MEDICINE LA English DT Article ID ARTHROSCOPIC REPAIR; KNEE; TEARS; SUTURE; MICROVASCULATURE; COMPLICATIONS; MENISCECTOMY; MOTION; ARROW; GOAT AB Meniscal repair is an important technique for the orthopaedic surgeon. As familiarity, equipment, and techniques improve, the interest in expanding the indications for application of meniscal repair also increases toward improving patient outcomes and long-term function. An overview of the indications, techniques, complications, and future direction of meniscal repair is presented in this article. C1 Wilford Hall USAF Med Ctr, Dept Orthopaed, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Sports Med, Lackland AFB, TX 78236 USA. RP Rispoli, DM (reprint author), Wilford Hall USAF Med Ctr, Dept Orthopaed, 59MDW-MKFO,2200 Berquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 94 TC 10 Z9 12 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0278-5919 J9 CLIN SPORT MED JI Clin. Sports Med. PD JAN PY 1999 VL 18 IS 1 BP 77 EP + DI 10.1016/S0278-5919(05)70131-9 PG 16 WC Sport Sciences SC Sport Sciences GA 160HC UT WOS:000078223600006 PM 10028118 ER PT J AU St Pierre, P Miller, MD AF St Pierre, P Miller, MD TI Posterior cruciate ligament injuries SO CLINICS IN SPORTS MEDICINE LA English DT Article ID TERM FOLLOW-UP; HUMAN KNEE; RECONSTRUCTION; INSTABILITY; ACCURACY; RUPTURE AB Treatment of posterior cruciate ligament (PCL) injuries has received renewed attention over the past few years. This article reviews the anatomy, natural history, and pathophysiology of posterior cruciate ligament injuries. Also described are the physical examination and proper imaging modalities used to diagnose this injury. Appropriate operative and nonoperative management methods are discussed. C1 Madigan Army Med Ctr, Dept Surg, Orthopaed Serv, Tacoma, WA 98431 USA. Wilford Hall USAF Med Ctr, Orthopaed Serv, San Antonio, TX 78236 USA. RP St Pierre, P (reprint author), Madigan Army Med Ctr, Dept Surg, Orthopaed Serv, Tacoma, WA 98431 USA. NR 62 TC 9 Z9 9 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0278-5919 J9 CLIN SPORT MED JI Clin. Sports Med. PD JAN PY 1999 VL 18 IS 1 BP 199 EP + PG 24 WC Sport Sciences SC Sport Sciences GA 160HC UT WOS:000078223600010 PM 10028122 ER PT S AU Desjardins, DD Hopper, DG AF Desjardins, DD Hopper, DG BE Hopper, DG TI Updated defense display market assessment SO COCKPIT DISPLAYS VI: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VI - Displays for Defense Applications CY APR 07-09, 1999 CL ORLANDO, FL SP SPIE AB This paper addresses the number, function and size of principal military displays and establishes a basis to determine the opportunities for technology insertion in the immediate future and into the next millennium. Principal military displays are defined as those occupying appreciable crewstation real-estate and/or those without which the platform could not carry out its intended mission. DoD "office" applications are excluded from this study. The military displays market is specified by such parameters as active area and footprint size, and other characteristics such as luminance, gray scale, resolution, angle, color, video capability, and night vision imaging system compatibility. Funded, future acquisitions, planned and predicted crewstation modification kits, and form-fit upgrades are taken into account. This paper provides an overview of the DoD niche market, allowing both government and industry a necessary reference by which to meet DoD requirements for military displays in a timely and cost-effective manner. The aggregate DoD installed base for direct-view and large-area military displays is presently estimated to be in excess of 313,000. Miniature displays are those which must be magnified to be viewed, involve a significantly different manufacturing paradigm and are used in helmet mounted displays and thermal weapon sight applications. Some 114,000 miniature displays are presently included within future weapon system acquisition plans. For vendor production planning purposes it is noted that foreign military sales could substantially increase these quantities. The vanishing vendor syndrome (VVS) for older display technologies continues to be a growing, pervasive problem throughout DoD, which consequently must leverage the more modern, especially flat panel, display technologies being developed to replace older, especially cathode ray tube, technology for civil-commercial markets. Total DoD display needs (FPD, HMD) are some 427,000. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Desjardins, DD (reprint author), USAF, Res Lab, Bldg 248,Rm 300,2255 H St, Wright Patterson AFB, OH 45433 USA. NR 16 TC 1 Z9 1 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 0-8194-3164-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3690 BP 2 EP 25 DI 10.1117/12.357585 PG 24 WC Engineering, Aerospace SC Engineering GA BN77P UT WOS:000082901900001 ER PT S AU Byrd, JC AF Byrd, JC BE Hopper, DG TI Lessons learned from the OIS saga SO COCKPIT DISPLAYS VI: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VI - Displays for Defense Applications CY APR 07-09, 1999 CL ORLANDO, FL SP SPIE DE OIS; Optical Imaging Systems; Active Matrix Liquid Crystal Display; AMLCD; display standard AB On 18 September 1998, Optical Imaging Systems (OIS) of Northville, MI ceased production of active Matrix Liquid Crystal Display (AMLCD) modules due to financial losses and the lack of a clear and immediate path to making the company profitable (see figure 1). Lack of OIS AMLCD modules has threatened to delay production delivery of aircraft to the US Air Force, Navy and Army. Other vendors make similar modules, but in most cases there is no interchangeable module immediately available. Consequently, military Program Offices and their contractors are working to overcome the present shortage. This paper discusses the non-standard parts/diminishing manufacturing sources problem and assesses various strategies that might be needed to prevent programs from being so dependent on unique sole-source devices in the future. It also suggests a list of display sizes and types that are good candidates for wide application and are thus less sensitive to events like the closing of one component manufacturer. C1 USAF, Aeronaut Syst Ctr, Integrated Avion Syst Branch, ASCENAS, Wright Patterson AFB, OH 45433 USA. RP Byrd, JC (reprint author), USAF, Aeronaut Syst Ctr, Integrated Avion Syst Branch, ASCENAS, 2530 Loop Rd W, Wright Patterson AFB, OH 45433 USA. NR 5 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 0-8194-3164-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3690 BP 34 EP 41 DI 10.1117/12.357605 PG 8 WC Engineering, Aerospace SC Engineering GA BN77P UT WOS:000082901900003 ER PT S AU Hopper, DG Meyer, FM Wodke, KE AF Hopper, DG Meyer, FM Wodke, KE BE Hopper, DG TI Status of display systems in B-52H SO COCKPIT DISPLAYS VI: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VI - Displays for Defense Applications CY APR 07-09, 1999 CL ORLANDO, FL SP SPIE DE display; interface; standard; digital; civil; military; commercial; avionics; instrument; gages; dial; indicator; monitor; meter; panel AB Display technologies for the B-52 were selected some 40 years ago have become unsupportable. Electromechanical and old cathode ray tube technologies, including an exotic six-gun 13 in. tube, have become unsupportable due to the vanishing vendor syndrome. Thus, it is necessary to insert new technologies which will be available for the next 40 years to maintain the capability heretofore provided by those now out of favor with the commercial sector. With this paper we begin a look at the status of displays in the B-52H, which will remain in inventory until 2046 according to current plans. From a component electronics technology perspective, such as displays, the B-52H provides several 10-year life cycle cost (LCC) planning cycles to consider multiple upgrades. Three Productivity, Reliability, Availability, and Maintainability (PRAM) projects are reviewed to replace 1950s CRTs in several sizes: 3, 9, and 13 in. A different display technology has been selected in each case. Additional display upgrades in may be anticipated and are discussed. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Hopper, DG (reprint author), USAF, Res Lab, 2255 H St Bldg 248,Rm 300, Wright Patterson AFB, OH 45433 USA. NR 14 TC 1 Z9 1 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 0-8194-3164-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3690 BP 83 EP 92 DI 10.1117/12.357623 PG 10 WC Engineering, Aerospace SC Engineering GA BN77P UT WOS:000082901900009 ER PT S AU Snow, MP Jackson, TW Meyer, FM Reising, JM Hopper, DG AF Snow, MP Jackson, TW Meyer, FM Reising, JM Hopper, DG BE Hopper, DG TI The AMLCD cockpit: promise and payoffs SO COCKPIT DISPLAYS VI: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VI - Displays for Defense Applications CY APR 07-09, 1999 CL ORLANDO, FL SP SPIE DE active matrix liquid crystal display; AMLCD; cockpit; displays; electronics; evaluation; human factors; large flat panels; situational awareness; test ID US MILITARY APPLICATIONS; PANEL DISPLAY TEST AB The active matrix liquid crystal display (AMLCD) has become the preferred flight instrument technology in avionics multifunction display applications. Current bubble canopy fighter cockpit applications involve sizes up to 7.8 x 7.8 in. active display. Dual use avionics versions of AMLCD technology are now as large as 6.7 x 6.7 in. active display area in the ARINC D sized color multifunction display (MFD). This is the standard instrument in all new Boeing transport aircraft and is being retrofitted into the C-17A. A special design of the ARINC D instrument is used in the Space Shuttle cockpit upgrade. Larger sizes of AMLCD were desired when decisions were made in the early 1990s for the F-22. Commercial AMLCD technology has now produced monitors at 1280 x 1024 resolution (1.3 megapixels) in sizes of 16 to 21 in. diagonal. Each of these larger AMLCDs has more information carrying capacity than the entire F-22A cockpit instrument panel shipset, comprising six separate smaller AMLCDs (1.2 megapixels total). The larger AMLCDs are being integrated into airborne mission crewstations for use in dim ambient lighting conditions. It is now time to identify and address the technology challenges of upgrading these larger AMLCDs for sunlight readable applications and of developing concepts for their integration into advanced bubble canopy fighter cockpits. The overall goals are to significantly increase the informational carrying capacity to bring both sensor and information fusion into the cockpit and, thereby, to enable a significant increase in warfighter situational awareness and effectiveness. A research cockpit was built using specialized versions of the IBM 16.1 in and two smaller 10 in. AMLCDs to examine human factors and display design issues associated with these next-generation AMLCD cockpit displays. This cockpit was later upgraded to allow greater reconfigurability and flexibility in the display hardware used to conduct part-task mission simulations;. The objective optical characterization of the AMLCDs used in this simulator and the cockpit design are described. Display formats under consideration for test in this cockpit are described together with some of the basic human factors engineering issues involved. Studies conducted in this cockpit will be part of an ongoing joint effort of the hardware-focused aerospace displays team and the pilot-focused human factors team in the Air Force Research Laboratory's Crew System Interface Division. The objective of these studies is to ascertain the payoffs of the large AMLCD promise in combat cockpits. C1 USAF, Res Lab, Crew Syst Interface Div, Wright Patterson AFB, OH 45433 USA. RP Snow, MP (reprint author), USAF, Res Lab, Crew Syst Interface Div, 2255 H St,Bldg 248,Rm 200, Wright Patterson AFB, OH 45433 USA. NR 19 TC 1 Z9 1 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 0-8194-3164-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3690 BP 103 EP 114 DI 10.1117/12.357587 PG 12 WC Engineering, Aerospace SC Engineering GA BN77P UT WOS:000082901900011 ER PT S AU Thayn, JR Ghrayeb, J Hopper, DG AF Thayn, JR Ghrayeb, J Hopper, DG BE Hopper, DG TI 3-D display design concept for cockpit and mission crewstations SO COCKPIT DISPLAYS VI: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VI - Displays for Defense Applications CY APR 07-09, 1999 CL ORLANDO, FL SP SPIE DE 3-D displays; cockpit displays; SLM; AOM; AMLCD; DMD; computer generated hologram AB Simple visual cues increase human awareness and perception and decrease reaction times. Humans are visual beings requiring visual cues to warn them of impending danger especially in combat aviation. The simplest cues are those that allow the individual to immerse themselves in the situations to which they must respond. Two-dimensional (2-D) display technology has real limits on what types of information and how much information it can present to the viewer without becoming disorienting or confusing. True situational awareness requires a transition from 2-D to three-dimensional (3-D) display technology. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Thayn, JR (reprint author), USAF, Res Lab, 2255 H St,Bldg 248 Rm 300, Wright Patterson AFB, OH 45433 USA. NR 11 TC 9 Z9 9 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 0-8194-3164-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3690 BP 180 EP 185 DI 10.1117/12.357592 PG 6 WC Engineering, Aerospace SC Engineering GA BN77P UT WOS:000082901900020 ER PT S AU Saini, GS AF Saini, GS BE Hopper, DG TI Update of status of OLED technology SO COCKPIT DISPLAYS VI: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VI - Displays for Defense Applications CY APR 07-09, 1999 CL ORLANDO, FL SP SPIE DE OLED; flat-panel displays; emissive; organic; polymer; transparent; flexible ID DISPLAYS AB Flat-panel displays are basically of two types: light valve (needs an external source of light) and emissive type (generates light at the display surface). The light emitting diode (LED) display is of the emissive type The inorganic LED displays have been in use for more than 25 years in one form or the other. Because of certain limitations of inorganic materials (such as luminous efficiency and color), LED applications have been limited. The recent discovery (over the past 15 years) of polymer and organic materials has changed LED prospects. It now may become possible to make LED displays that are inexpensive, bright, low-power, large size, and at the same time provide full color. If present research objectives are met, LEDs, especially organic LEDs (OLEDs), may have the potential to revolutionize a certain segment of flat-panel display market. This paper discusses various types of OLED technologies with particular reference to Small Molecule and Conjugated Polymer displays. Some unique versions of these displays such as transparent displays and flexible displays will also be discussed. A part of the discussion will be devoted to various driver circuitry and full color generation schemes. A comprehensive list of various research efforts in OLED technology all over the world will be presented with their differentiating features. The strength of the underlying technology and the challenges facing these types of displays will be discussed. C1 USAF, Res Lab, Visual Display Syst Branch, Wright Patterson AFB, OH 45433 USA. RP Saini, GS (reprint author), USAF, Res Lab, Visual Display Syst Branch, 2255 H St,Bldg 248 Rm 207B, Wright Patterson AFB, OH 45433 USA. NR 10 TC 0 Z9 0 U1 1 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3164-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3690 BP 225 EP 235 DI 10.1117/12.357615 PG 11 WC Engineering, Aerospace SC Engineering GA BN77P UT WOS:000082901900025 ER PT S AU Rockwell, BA Cain, CP Roach, WP Thomas, RJ AF Rockwell, BA Cain, CP Roach, WP Thomas, RJ BE Reed, MK Neev, J TI Safe use of ultrashort lasers SO COMMERCIAL AND BIOMEDICAL APPLICATIONS OF ULTRAFAST LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Commercial and Biomedical Applications of Ultrafast Lasers CY JAN 28-29, 1999 CL SAN JOSE, CA SP SPIE DE eye; safety; laser; nonlinear optics; retinal damage ID VISIBLE RETINAL LESIONS; PRIMATE EYE; PULSES; THRESHOLD; DAMAGE AB We review the progress made in determining the trends in retinal damage from laser pulses from one nanosecond to one hundred femtoseconds in the visible and near-infrared wavelength regimes. These trends have suggested a maximum permissible exposure limit (MPE) for laser pulses in the retinal hazard regime between one nanosecond and one hundred femtoseconds. We discuss the likely mechanisms for retinal damage and the implications to using ultrashort laser systems safely. We will summarize the challenges in appropriately addressing safety when using ultrashort laser systems in advanced applications. C1 USAF, Human Effectiveness Directorate, Directed Energy Bioeffects Div, Opt Radiat Branch, Brooks AFB, TX 78235 USA. RP Rockwell, BA (reprint author), USAF, Human Effectiveness Directorate, Directed Energy Bioeffects Div, Opt Radiat Branch, 8111 18th St, Brooks AFB, TX 78235 USA. NR 19 TC 0 Z9 0 U1 1 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 0-8194-3086-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3616 BP 32 EP 39 DI 10.1117/12.351838 PG 4 WC Engineering, Biomedical; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN29H UT WOS:000081442300005 ER PT J AU Kerans, RJ Parthasarathy, TA AF Kerans, RJ Parthasarathy, TA TI Crack deflection in ceramic composites and fiber coating design criteria SO COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING LA English DT Article; Proceedings Paper CT International Symposium on Ceramic Matrix Composites CY OCT 28-30, 1997 CL TOKYO, JAPAN SP AFOSR, AOARD, SAMPE, Japan Chapter, Japan Soc Composite Mat, Soc Mat Sci, Japanese Soc Mechan Engineers DE composites interfaces; fiber coatings; debonding; crack deflection ID BRITTLE-MATRIX COMPOSITES; DISSIMILAR ELASTIC-MATERIALS; MULTILAYERED INTERPHASES; FRACTURE-TOUGHNESS; PYROLYTIC CARBON; INTERFACE; MECHANICS; BEHAVIOR AB It is widely understood that the remarkable toughnesses demonstrated by some ceramic composites are dependent upon deflection of matrix cracks into fiber/matrix interfacial cracks. Carbon and BN fiber coatings are ideally suited for promotion of such crack deflection, but have the unfortunate weakness of limited oxidation resistance. The rational design of oxidation-resistant alternative fiber coatings is facilitated by consideration of the details of crack deflection, growth of interfacial cracks, and subsequent sliding along the interfacial crack surface. This work discusses some of these details and the implications regarding the design and testing of alternative fiber coating systems. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, WL MLLN, Wright Patterson AFB, OH 45433 USA. RP Kerans, RJ (reprint author), USAF, Res Lab, Mat & Mfg Directorate, WL MLLN, Wright Patterson AFB, OH 45433 USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 27 TC 53 Z9 55 U1 2 U2 11 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1359-835X J9 COMPOS PART A-APPL S JI Compos. Pt. A-Appl. Sci. Manuf. PY 1999 VL 30 IS 4 BP 521 EP 524 DI 10.1016/S1359-835X(98)00144-4 PG 4 WC Engineering, Manufacturing; Materials Science, Composites SC Engineering; Materials Science GA 175ZA UT WOS:000079124900020 ER PT J AU Tandon, GP Kim, RY Warrier, SG Majumdar, BS AF Tandon, GP Kim, RY Warrier, SG Majumdar, BS TI Influence of free edge and corner singularities on interfacial normal strength: application in model unidirectional composites SO COMPOSITES PART B-ENGINEERING LA English DT Article DE interface/interphase; straight-sided ID FIBER-REINFORCED COMPOSITES; METAL MATRIX COMPOSITES; LAMINATED COMPOSITES; TRANSVERSE RESPONSE; FAILURE; MECHANISMS; SURFACE AB The present study was aimed at designing and evaluating some simple test methods for estimating the normal strength of the fiber-matrix interface in unidirectional composites. In order to remove the influence of the free surfaces from tests on traditional straight-sided exposed fiber specimens, two alternate geometries, namely, embedded fiber and cruciform specimen, were considered. These specimens, based on a model transparent material combination, were incrementally loaded in tension to failure, while strain and acoustic emission activity were continuously monitored for damage initiation. The cruciform geometry provides the largest value of failure stress, the embedded fiber geometry yields intermediate value, whereas the exposed fiber specimen results in lowest failure stress values. Analytical and computational modelling, which combines an asymptotic analysis based on Mellin transform at the local scale with a finite element procedure at the global scale, was then utilized to rationalize the different strength estimates. Results demonstrate that stress field singularities control damage initiation in straight-sided samples and emphasize the success of cross-shaped design in forcing debond initiation in the interior of the sample (region free of initial stress singularities). (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Tandon, GP (reprint author), AdTech Syst Res Inc, 1342 N Fairfield Rd, Dayton, OH 45432 USA. NR 38 TC 22 Z9 27 U1 2 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1359-8368 J9 COMPOS PART B-ENG JI Compos. Pt. B-Eng. PY 1999 VL 30 IS 2 BP 115 EP 134 DI 10.1016/S1359-8368(98)00046-8 PG 20 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA 178ZW UT WOS:000079299900001 ER PT J AU Miller, TC AF Miller, TC TI Modelling of plane strain interfacial fracture in incompressible materials SO COMPOSITES PART B-ENGINEERING LA English DT Article DE interface/interphase; fracture; defects ID BIMATERIAL INTERFACES; CRACKS AB Numerical modelling of a photoelastic experiment is discussed. The experiment examined incompressible materials under plane strain conditions, which results in a simplified analysis owing to a vanishing of the bimaterial parameter. The photoelastic experiment used the stress freezing method to determine near tip stresses in interfacial cracks in bimaterial specimens. Different crack orientations were used to produce different mode mixities. Photoelastic fringe patterns were analyzed to determine the magnitude and phase angle of the complex stress intensity factor. These experiments were modeled using a finite element analysis to determine the field variables near the tips of the interfacial cracks. Magnitudes of the complex stress intensity factors are found from J integral values, derived using the domain integral approach, and the phase angles are determined using extrapolation of the bond line traction data to r = 0. The results show that this approach is a useful way to characterize completely the complex stress intensity factor in incompressible linear elastic bimaterial combinations under plane strain conditions. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Edwards, CA 93524 USA. RP Miller, TC (reprint author), USAF, Res Lab, 10 E Saturn Blvd, Edwards, CA 93524 USA. NR 18 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1359-8368 J9 COMPOS PART B-ENG JI Compos. Pt. B-Eng. PY 1999 VL 30 IS 3 BP 291 EP 296 DI 10.1016/S1359-8368(98)00064-X PG 6 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA 184VR UT WOS:000079634900008 ER PT J AU Agnes, GS Mall, S AF Agnes, GS Mall, S TI Structural integrity issues during piezoelectric vibration suppression of composite structures SO COMPOSITES PART B-ENGINEERING LA English DT Article DE vibration; structural integrity; smart materials ID PERFORMANCE; ACTUATORS; FRACTURE; CERAMICS AB Piezoelectric materials are one of a group of materials used to construct smart or adaptive structures. The control of structural vibrations is a promising real-world application of this technology for aerospace structures. The modeling and application of piezoelectric vibration suppression technology is reviewed-concentrating on the notable work of the past decade. Several real-world aerospace applications are also discussed demonstrating the near-term promise of this technology. Next the structural issues are reviewed establishing that a very limited knowledge of fatigue and fracture behavior for the adaptive composite structures exist. Therefore, increased attention to structural integrity of the vibration suppression systems is required before their real-world application can commence. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Mat Mfg Directorate, AFIT ENY, Wright Patterson AFB, OH 45433 USA. USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, Res Lab, Mat Mfg Directorate, AFIT ENY, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 45 TC 7 Z9 9 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1359-8368 J9 COMPOS PART B-ENG JI Compos. Pt. B-Eng. PY 1999 VL 30 IS 7 BP 727 EP 738 DI 10.1016/S1359-8368(99)00029-3 PG 12 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA 265ZR UT WOS:000084276600012 ER PT J AU Sanders, BP Mall, S Pittman, RB AF Sanders, BP Mall, S Pittman, RB TI The effects of frequency and temperature on the fatigue behavior of a unidirectional titanium-matrix composite SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article ID ELEVATED-TEMPERATURE; LAMINATE AB In this study the effects of frequency and temperature on the fatigue behavior of a unidirectional titanium-matrix composite (TMC), SCS-6/Ti-6-4, have been investigated. Fatigue tests were conducted under tension-tension, load-controlled, isothermal conditions. Specimens were cycled over a range of frequencies (0.01, 0.1, 1 and 10 Hz) and at different temperatures (23 degrees C, 370 degrees C, 427 degrees C and 538 degrees C) in the laboratory environment. It was observed that there was no dependence on frequency below 400 degrees C, but above 400 degrees C the test frequency affected the cyclic stress/strain response, damage mechanisms, and fatigue life. Plots of test frequency versus cycles to failure showed that fatigue life was more cycle-dependent at higher frequencies and more time-dependent at lower frequencies. Comparisons of fatigue lives under different isothermal temperature environments showed that these frequency effects were magnified as the temperature increased above 427 degrees C which was a result of the time-dependent nature of the matrix at higher temperatures. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, ENY, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM small@afit.af.mil NR 20 TC 5 Z9 5 U1 1 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0266-3538 J9 COMPOS SCI TECHNOL JI Compos. Sci. Technol. PY 1999 VL 59 IS 4 BP 583 EP 591 DI 10.1016/S0266-3538(98)00100-6 PG 9 WC Materials Science, Composites SC Materials Science GA 180TR UT WOS:000079401700011 ER PT J AU Gundel, DB Warrier, SG Miracle, DB AF Gundel, DB Warrier, SG Miracle, DB TI The transverse tensile behavior of SiC-fiber/Ti-6Al-4V composites 2. Stress distribution and interface failure SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE interface strength; finite-element analysis; transverse tensile testing; concentric cylinder modeling; SiC-fiber/titanium-matrix composites ID FIBER SCS-6/TI-6AL-4V COMPOSITE; SIC/TI-6AL-4V COMPOSITES; SIC FIBER; SINGLE AB The use of a cruciform specimen geometry has allowed the quantification of the applied stress where the interface debonds in single and multiple-fiber titanium-matrix composites under transverse tension. The applied debond stress, however, is not equal to the local interface stresses and is dependent on specimen geometry. In the present study, both analytical and numerical techniques were employed to determine the interface stresses for several fiber arrangements. For single-fiber tests, the specimen thickness was found to have little influence over the range modeled (250-550 mu m). The presence of neighboring fibers was found to significantly alter the interfacial stress levels upon loading for a single-ply composite, but not for a multiple-ply arrangement, where only the residual stress level was influenced. The analyses were applied to experimental results to estimate the interface strength and to explain the applied debond loads measured for different fiber arrangements with the three SiC fibers studied in Part I. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 SYSTRAN Corp, Dayton, OH 45432 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Gundel, DB (reprint author), 3M Austin Ctr, 6801 River Pl Blvd, Austin, TX 78726 USA. NR 18 TC 21 Z9 24 U1 1 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0266-3538 J9 COMPOS SCI TECHNOL JI Compos. Sci. Technol. PY 1999 VL 59 IS 7 BP 1087 EP 1096 DI 10.1016/S0266-3538(98)00153-5 PG 10 WC Materials Science, Composites SC Materials Science GA 199XK UT WOS:000080509200011 ER PT S AU Scott, MB Yeo, YK Hengehold, RL Scofield, JD AF Scott, MB Yeo, YK Hengehold, RL Scofield, JD BE Sakaki, H Woo, JC Yokohama, N Hirayama, Y TI High temperature (500 degrees C) implantation study of P+ and N+ implanted epitaxial N-type 4H-SiC SO COMPOUND SEMICONDUCTORS 1998 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 25th International Symposium on Compound Semiconductors CY OCT 12-16, 1998 CL NARA, JAPAN SP Inst Electr, Informat & Commun Engineers Japan, IEEE Electron Devices Soc, IEEE Lasers & Electro Opt Soc, Japan Soc Appl Phys AB Hall-effect and cathodoluminescence (CL) measurements have been made for high temperature (500 degreesC) P+- and N+-implanted n-type 4H-SiC to assess the activation efficiency and implantation-related damage recovery. Hall-effect measurement results indicate optimum anneal temperatures of similar to1400 and similar to1600 degreesC, and activation efficiencies of 90 and 33% for the N- and P-implanted n-type 4H-SiC, respectively. Hall mobilities in both N- and P-implanted samples increase with anneal temperature from 1400 to 1800 degreesC. The CL spectra from the N-implanted n-SiC showed no near bandedge N-associated zero phonon lines (ZPL) at 3.24 eV, which is due to the residual nitrogen in n-SiC, though the CL spectra from the P-implanted n-SiC contained the near bandedge ZPL, but very weak. A ZPL pair at 2.63 eV and its phonon replica were found for the SiC:N. The 2.63 eV peak pair is believed to be related to a nitrogen-complex formed during implantation/annealing. The CL spectra for the SiC:P contained a ZPL pair at 2.91 eV, which is believed to be damage-related, and its associated phonon replica spectra. For both donor implanted samples, phonon energies of 37, 68.5, 82.5, and 108 meV were obtained from the ZPL peak pairs and respective phonon replica spectra. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Scott, MB (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0951-3248 BN 0-7503-0611-4 J9 INST PHYS CONF SER PY 1999 IS 162 BP 763 EP 768 PG 6 WC Physics, Multidisciplinary SC Physics GA BU98T UT WOS:000177562700124 ER PT J AU Gettayacamin, M Hansukjariya, P Corcoran, KD Young, GD MacMillan, JG AF Gettayacamin, M Hansukjariya, P Corcoran, KD Young, GD MacMillan, JG TI Vaginal cytology of the lesser bandicoot rat (Bandicota savilei) SO CONTEMPORARY TOPICS IN LABORATORY ANIMAL SCIENCE LA English DT Article ID RICKETTSIA-TSUTSUGAMUSHI; THAILAND AB The lesser bandicoot rat (Bandicota savilei) is a wild field rat commonly found in Thailand. Vaginal smears were obtained from five colony-bent animals twice daily for 28 days and stained with Giemsa stain, The external appearance of the vulva and appearance of the tip of vaginal swabs were recorded, All cells, including nucleated or keratinized epithelial cells and leukocytes, were quantified by percentage. No changes of the external genitalia were observed. The gross appearance of the vaginal swab may distinguish estrus and diestrus. Vaginal swabs contained a white or yellow material during estrus or diestrus, respectively. Changes in vaginal cytology at each stage of the estrous cycle of the lesser bandicoot rat were similar to those of the common laboratory rat, Estrus stages of the five rats occurred every 3 or 4 daps. One female was introduced to a male after diestrus and produced a litter of six pups 27 days after pairing. C1 USA Med Component, Dept Vet Med, Armed Forces Res Inst Med Sci, Bangkok 10400, Thailand. OEVM, Comparat Med Branch, AL, Wright Patterson AFB, OH 45433 USA. USA, Ctr Hlth Promot & Prevent Med, Aberdeen Proving Ground, MD 21010 USA. USAF, Armstrong Lab, Vet Sci Div, Brooks AFB, TX 78235 USA. RP Gettayacamin, M (reprint author), USA Med Component, Dept Vet Med, Armed Forces Res Inst Med Sci, 315-6 Rajvithi Rd, Bangkok 10400, Thailand. NR 14 TC 3 Z9 3 U1 0 U2 0 PU AMER ASSOC LABORATORY ANIMAL SCIENCE PI MEMPHIS PA 9190 CRESTWYN HILLS DR, MEMPHIS, TN 38125 USA SN 1060-0558 J9 CONTEMP TOP LAB ANIM JI Contemp. Top. Lab. Anim. Sci. PD JAN PY 1999 VL 38 IS 1 BP 76 EP 80 PG 5 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 174PZ UT WOS:000079044700020 PM 12086458 ER PT S AU Cliver, EW AF Cliver, EW BE Kotrc, P Markova, E Rusin, V TI Solar eclipse workshop: Closing comments SO CONTRIBUTIONS OF THE ASTRONOMICAL OBSERVATORY SKALNATE PLESO, VOL XXVII, NO 3-BK SAMPLE XXVII. NO 3: PROCEEDINGS OF THE 1999 SOLAR ECLIPSE WORKSHOP SE CONTRIBUTIONS OF THE ASTRONOMICAL OBSERVATORY SKALNATE PLESO-B SAMPLE LA English DT Proceedings Paper CT 1999 Solar Eclipse Workshop CY SEP 08, 1998 CL PRAGUE, CZECH REPUBLIC SP Acad Sci, Astron Inst, Ondrejov, Czech Astron Soc, Slovak Astron Soc C1 USAF, Res Lab, Bedford, MA 01731 USA. RP Cliver, EW (reprint author), USAF, Res Lab, Bedford, MA 01731 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SLOVAK ACADEMY SCIENCES ASTRONOMICAL INSTITUTE PI TATRANSKA LOMNICA PA 059 60 TATRANSKA LOMNICA, SLOVAKIA SN 1335-1842 J9 CONTR AST O PY 1999 VL 28 IS 3 BP 300 EP 301 PG 2 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN03H UT WOS:000080462300021 ER PT B AU Scott, RE AF Scott, RE BE Hylko, JM Salyer, RL TI Laser imaging systems in support of the Cassini Launch SO CREATION AND FUTURE LEGACY OF STOCKPILE STEWARDSHIP: ISOTOPE PRODUCTION, APPLICATIONS, AND CONSUMPTION LA English DT Proceedings Paper CT 32nd Annual Midyear Topical Meeting of the Health-Physics-Society CY JAN 24-27, 1999 CL ALBUQUERQUE, NM SP Hlth Phys Soc Rio Grande Chapter AB This paper is a review of the laser safety planning for the use of three laser imaging systems in support of the 15 October 1997 Cassini Launch from the Eastern Test Range, which is the Kennedy Space Center and Cape Canaveral Air Station(CCAS). The need for laser imaging systems is discussed, along with the health physics measures required for the safe use of these atmospheric lasers. C1 USAF, Patrick AFB, FL 32925 USA. RP Scott, RE (reprint author), USAF, 1201 Minuteman St,45 AMDS-SGPS, Patrick AFB, FL 32925 USA. NR 0 TC 2 Z9 3 U1 0 U2 0 PU MEDICAL PHYSICS PUBLISHING PI MADISON PA 4513 VERNON BLVD, MADISON, WI 53705 USA BN 0-944838-88-X PY 1999 BP 151 EP 155 PG 5 WC Nuclear Science & Technology; Physics, Applied; Radiology, Nuclear Medicine & Medical Imaging SC Nuclear Science & Technology; Physics; Radiology, Nuclear Medicine & Medical Imaging GA BM63F UT WOS:000079308800024 ER PT B AU Davis, TM Reilly, J Tomlinson, BJ AF Davis, TM Reilly, J Tomlinson, BJ BE Ross, RG TI Air force research laboratory cryocooler technology development SO CRYOCOOLERS 10 LA English DT Proceedings Paper CT 10th International Cryocooler Conference CY MAY 26-28, 1998 CL LOCKHEED MARTIN ADV TECHNOL CTR, MONTEREY, CA HO LOCKHEED MARTIN ADV TECHNOL CTR AB This paper presents an overview of the cryogenic refrigerator and cryogenic integration programs in development and characterization under the Cryogenic Technology Group, Space Vehicles Directorate of the Air Force Research Laboratory (AFRL). The vision statement for the group is to support the space community as the center of excellence for developing and transitioning space cryogenic thermal management technologies. The primary customers for the AFRL cryogenic technology development programs are Ballistic Missile Defense Organization (BMDO), the Air Force Space Based Infrared System (SBIRS) Low program office, and other DoD space surveillance programs. This paper will describe the range of Stirling, pulse tube, reverse Brayton, Joule-Thomson cycle cryocoolers, and sorption cryocoolers currently under development to meet current and future Air Force and DoD requirements. The AFRL customer single stage cooling requirements at 10 K, 35 K, 60 K, 150 K, and multi-stage cooling requirements at 35/60 K are addressed. In order to meet these various requirements, the AFRL Cryogenic Technology Group is pursuing various strategic cryocooler and cryogenic integration options. The Air Force Research Laboratory is also developing several advanced cryogenic integration technologies that will result in the reduction in current cryogenic system integration penalties and design time. These technologies include the continued development of the Cryogenic Systems Integration Model (CSIM), 60 K and 100 K thermal storage units and heat pipes, cryogenic straps, thermal switches, and development of an Integrated Lightweight Cryogenic Bus (CRYOBUS). C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Davis, TM (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 6 TC 1 Z9 1 U1 1 U2 5 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46120-X PY 1999 BP 21 EP 32 PG 12 WC Thermodynamics SC Thermodynamics GA BR59Y UT WOS:000166912300002 ER PT B AU Tomlinson, BJ Gilbert, A Bruning, J AF Tomlinson, BJ Gilbert, A Bruning, J BE Ross, RG TI Endurance evaluation of long-life space cryocoolers at AFRL - An update SO CRYOCOOLERS 10 LA English DT Proceedings Paper CT 10th International Cryocooler Conference CY MAY 26-28, 1998 CL LOCKHEED MARTIN ADV TECHNOL CTR, MONTEREY, CA HO LOCKHEED MARTIN ADV TECHNOL CTR AB The Air Force Research Laboratory (AFRL), under the sponsorship of the Ballistic Missile Defense Organization (BMDO), developed several long-life cryocooler concepts designed to meet military space system cryogenic refrigeration performance and mission life specifications. These coolers include Stirling cycle, pulse tube, and reverse Brayton cycle machines developed to varying stages of technological maturity. AFRL's Cryocooler Characterization Laboratory (CCL) and the Jet Propulsion Laboratory (JPL) have extensively assessed the thermodynamic performance capabilities of these newly emerging coolers. However, a complete demonstration of the technological maturity of these coolers must include long-term endurance characterization to help determine the long-life potential of these machines. Endurance evaluation attempts to demonstrate that the baseline performance of these machines is maintainable for the 5-10 year design operational life in an environment simulating the conditions of their use in space. These trials also surface any wear out, drift, and fatigue related failure mechanisms associated with cooler designs, allowing for adequate design modifications to improve the long-life potential of these machines. Endurance evaluation also helps to quantify performance shifts over long time periods that must be accounted for in cooler control schemes and spacecraft thermal designs. This paper presents endurance evaluation results for long-life space coolers currently under evaluation at AFRL. Data includes updates on the reverse Brayton cooler and the diaphragm flexure Stirling cooler, both of which have been undergoing endurance evaluation since 1995 and 1996, respectively. It also presents data on new endurance trails associated with several pulse tube and Stirling cycle machines more recently developed by AFRL and delivered to the CCL for characterization and evaluation. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Tomlinson, BJ (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46120-X PY 1999 BP 33 EP 42 PG 10 WC Thermodynamics SC Thermodynamics GA BR59Y UT WOS:000166912300003 ER PT B AU Tomlinson, BJ Davidson, D Lanes, C Burt, W Gilbert, A AF Tomlinson, BJ Davidson, D Lanes, C Burt, W Gilbert, A BE Ross, RG TI Multispectral Thermal Imager (MTI) space cryocooler development, integration, and test SO CRYOCOOLERS 10 LA English DT Proceedings Paper CT 10th International Cryocooler Conference CY MAY 26-28, 1998 CL LOCKHEED MARTIN ADV TECHNOL CTR, MONTEREY, CA HO LOCKHEED MARTIN ADV TECHNOL CTR AB This paper presents the selection rationale, development, flight qualification, flight integration, and characterization testing for the Multispectral Thermal Imager (MTT) cryocooler. The MTI program is a technology demonstration effort led by Sandia National Laboratories (SNL) under the sponsorship of the Department of Energy. As part of this effort, Sandia will build, deploy, and operate a small satellite, the core of which is a telescope and focal plane that is cooled to 75 Kelvin using a TRW supplied pulse tube cryocooler. This application, a milestone in the application of active cryocooling, is intended to demonstrate the utility of large capacity, non-split, cryocoolers for space missions. The cooler for MTI is a near identical, tailored version of the TRW 6020 pulse tube cryocooler, a product of recent long life cooler technology advances, which can provide greater than 2 Watts of cooling at 60 Kelvin. The focal plane is under development at Santa Barbara Research Center (SBRC). Both items are one-of-kind products whose integration occurs in the later phases of the MTI system build, thereby posing potential schedule risks to the overall program success. The existence of a TRW 6020 pulse tube at the Air Force Research Laboratory (AFRL), and it's similarity to the MTI cryocooler, allowed for characterization testing to be performed with a focal plane thermal mock-up to mitigate this risk. This test and the development of a new thermal strap design will also be presented. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Tomlinson, BJ (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46120-X PY 1999 BP 129 EP 138 PG 10 WC Thermodynamics SC Thermodynamics GA BR59Y UT WOS:000166912300014 ER PT B AU Tomlinson, BJ Gilbert, A Bruning, J AF Tomlinson, BJ Gilbert, A Bruning, J BE Ross, RG TI Heat rejection effects on cryocooler performance prediction SO CRYOCOOLERS 10 LA English DT Proceedings Paper CT 10th International Cryocooler Conference CY MAY 26-28, 1998 CL LOCKHEED MARTIN ADV TECHNOL CTR, MONTEREY, CA HO LOCKHEED MARTIN ADV TECHNOL CTR AB Satellite developers have the complex task of designing spacecraft thermal management systems that must remain stable despite extremely dynamic operating environments. Developing spacecraft thermal management systems that depend on predictable cryocooler performance is one of the most challenging aspects of space thermal system design. Developers must often rely on very sparse cryocooler performance data when conducting their system-level tradeoffs. While significant data is becoming available on newly emerging coolers, most experimentation is performed at or near a cooler's design point operation based on somewhat generic or dynamic spacecraft requirements. This makes it extremely difficult to examine all possible spacecraft operating scenarios and their effects on cryocooler performance. Off-design point performance mapping is also often limited by time constraints, either imposed by system or follow-on cooler development schedules. However, in characterizing cryocoolers at the Air Force Research Laboratory (AFRL), considerable off-nominal performance mapping has allowed empirical modeling of quantifiable parametric relationships. These models tie together the interrelationships between key cryocooler parameters, both operational and environmental. forming precise performance prediction methods useful over most potential operating ranges. This paper presents an approach to developing performance prediction models for the coolers undergoing characterization and evaluation at AFRL's Cryocooler Characterization Laboratory (CCL), Cooler concepts under investigation include various Stirling cycle, pulse tube, and reverse Brayton cycle machines. Particular emphasis is placed on better quantifying the relationship of heat rejection temperature to both independent and dependent cryocooler control parameters. These models may become extremely useful design tools that could assist system developers in selecting the appropriate cooler for their operational and mission needs. It will also aid spacecraft developers in adequately compensating for cooler parametric sensitivities and time dependent performance drift in their satellite thermal management designs. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Tomlinson, BJ (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46120-X PY 1999 BP 723 EP 732 PG 10 WC Thermodynamics SC Thermodynamics GA BR59Y UT WOS:000166912300085 ER PT S AU Marmelstein, RE Hammack, LP Lamont, GB AF Marmelstein, RE Hammack, LP Lamont, GB BE Dasarathy, BV TI A concurrent approach for evolving compact decision rule sets SO DATA MINING AND KNOWLEDGE DISCOVERY: THEORY, TOOLS, AND TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Data Mining and Knowledge Discovery - Theory, Tools, and Technology CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE - Int Soc Opt Engn AB The induction of decision rules from data is important to many disciplines including artificial intelligence and pattern recognition. To improve the state of the art in this area, we introduced the Genetic Rule and Classifier Construction Environment (GRaCCE). It was previously shown(1) that GRaCCE consistently evolved decision rule sets from data that were significantly more compact than those produced by other methods (such as decision tree algorithms). The primary disadvantage of GRaCCE, however, is its relatively poor run-time execution performance. In this paper, a concurrent version of the GRaCCE architecture is introduced which improves the efficiency of the original algorithm. A prototype of the algorithm is tested on an in-house parallel processor configuration and the results are discussed. C1 USAF, Inst Tecton, Grad Sch Engn, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Marmelstein, RE (reprint author), USAF, Inst Tecton, Grad Sch Engn, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 17 TC 1 Z9 1 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 0-8194-3169-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3695 BP 52 EP 62 DI 10.1117/12.339990 PG 3 WC Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Optics SC Computer Science; Optics GA BM94P UT WOS:000080212300006 ER PT J AU Meffert, JJ AF Meffert, JJ TI Environmental skin diseases and the impact of common dermatoses on medical readiness SO DERMATOLOGIC CLINICS LA English DT Review ID ERYTHEMA AB IGNE; ALOE-VERA CREAM; FROSTBITE INJURIES; SUN PROTECTION; COLD INJURY; SHADOW RULE; EXPOSURE; WORKERS; CANCER; BURN AB The environmental extremes in which soldiers exercise and fight, like the environmental extremes in which many civilians encounter occupationally and recreationally, can prove to be a significant cause for morbidity and decreased effectiveness. A variety of skin diseases are related to occupational exposure to dusts and ultraviolet radiation as a well known cause of cutaneous damage. As more is understood about the biochemical factors involved in frostbite injury treatment recommendations have changed. Too much water, hot or cold, is a continued source of cutaneous misery to the soldier in the field. Finally, even common minor skin ailments can incapacitate the sufferer when confronted with unfavorable environments. C1 Brooke Army Med Ctr, Dept Dermatol, San Antonio Uniformed Serv Hlth Educ Consortium, Ft Sam Houston, TX 78234 USA. RP Meffert, JJ (reprint author), USAF, 19626 Encino Knoll, San Antonio, TX 78259 USA. NR 143 TC 4 Z9 4 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0733-8635 J9 DERMATOL CLIN JI Dermatol. Clin. PD JAN PY 1999 VL 17 IS 1 BP 1 EP + DI 10.1016/S0733-8635(05)70066-8 PG 18 WC Dermatology SC Dermatology GA 162VV UT WOS:000078368400002 PM 9986992 ER PT S AU Clark, N Furth, P AF Clark, N Furth, P BE Courtois, B Demidenko, S TI Design and performance evaluation of a silicon eye using micro-mirrors SO DESIGN, CHARACTERIZATION, AND PACKAGING FOR MEMS AND MICROELECTRONICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Design, Characterization, and Packaging for MEMS and Microelectronics CY OCT 27-29, 1999 CL QUEENSLAND, AUSTRALIA SP SPIE, IREE Soc, Queensland Govt State Dev, Griffith Univ Microelectr Engn Soc, Australia, IEEE, Electron Devices Soc, Electrochem Soc DE smart vision chips; adaptive optics; micro-mirrors; wavefront sensing; wavefront correction; deformable mirrors ID SQUARES AB We have developed a new paradigm, based on massively parallel analog processing coupled with a MEMs micro-mirror device, for developing intelligent vision systems that is capable of performing adaptive optics at rates exceeding 1 kHz and 3D imaging at bandwidths exceeding 100 Hz. The design and modeling methodologies associated with our smart vision chip are presented along with experimental results that characterize its performance. We also present design and modeling methodologies of our micro-mirror devices along with experimental results that characterize their performance in typical adaptive optic systems. Finally, we present modeling and simulation methodologies of adaptive optics systems along with experimental results used to design and test an adaptive optic system. The design and modeling methodologies that are presented lend themselves to facilitating the design and development of a wide variety other sophisticated vision systems. In addition to speed, our approach offers advantages in low cost batch fabrication, compact size, low power consumption, and radiation tolerance, making it ideal for many applications. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Clark, N (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 13 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 0-8194-3494-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3893 BP 304 EP 313 DI 10.1117/12.368437 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Engineering; Materials Science; Optics GA BP26M UT WOS:000084509900031 ER PT S AU Thai, S Hayduk, M AF Thai, S Hayduk, M BE Osinski, M Chua, SJ Chichibu, SF TI Passive mode locking in erbium-ytterbium fiber lasers SO DESIGN, FABRICATION AND CHARACTERIZATION OF PHOTONIC DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Design, Fabrication, and Characterization of Photonic Devices CY NOV 30-DEC 03, 1999 CL SINGAPORE, SINGAPORE SP SPIE, Nanyang Technol Univ, SPIE, Singapore Chapter, Inst Phys, USAF, Asian Off Aerosp Res & Dev, USA, Res Off Far E DE fiber laser; passive mode locking; multiple quantum well; saturable absorber; erbium-ytterbium AB A novel mode-locked erbium-ytterbium fiber laser operating at 1550 nm using multiple quantum well (MQW) saturable absorbers was developed. The laser was constructed in a Fabry-Perot configuration using a fiber Bragg grating as a front reflector and a fiber Bragg grating output as a back reflector of the laser cavity. The passive mode-locking element placed inside the laser cavity is a 75 period InGaAs/InAlAs MQW saturable absorber grown lattice matched on an InP substrate. The output of the laser was taken through the other available port of a wavelength-division demultiplexer. The laser produced mode-locked output pulse trains at 16.67-MHz repetition rate and 10 mW of average output power. C1 USAF, Res Lab, Sensors Directorate, Rome, NY 13441 USA. RP Thai, S (reprint author), USAF, Res Lab, Sensors Directorate, 25 Elect Pkwy, Rome, NY 13441 USA. NR 8 TC 0 Z9 0 U1 1 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 0-8194-3498-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3896 BP 290 EP 297 DI 10.1117/12.370323 PG 2 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics; Physics, Applied SC Engineering; Materials Science; Optics; Physics GA BP26P UT WOS:000084510200030 ER PT S AU Sutherland, RL Natarajan, LV Tondiglia, VP Pogue, RT Siwecki, SA Brandelik, DM Epling, BL Berman, E Wendel, C Schmitt, MG AF Sutherland, RL Natarajan, LV Tondiglia, VP Pogue, RT Siwecki, SA Brandelik, DM Epling, BL Berman, E Wendel, C Schmitt, MG BE Cindrich, I Lee, SH Sutherland, RL TI Holographic PDLCs for spatial light intensity modulation SO DIFFRACTIVE AND HOLOGRAPHIC TECHNOLOGIES, SYSTEMS, AND SPATIAL LIGHT MODULATORS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Diffractive and Holographic Technologies, Systems, and Spatial Light Modulators VI CY JAN 27-29, 1999 CL SAN JOSE, CA SP SPIE, Defense Adv Res Projects Agency DE switchable holograms; holographic polymer-dispersed liquid crystals; spatial light modulators ID CRYSTAL COMPOSITE-MATERIALS; GRATINGS; POLYMER AB Holographic polymer-dispersed liquid crystals are switchable holograms exhibiting electrically controllable diffraction efficiency. Such devices form the building blocks for several applications under active consideration including spatial light modulators. Several demanding requirements are placed on switchable holograms for these applications, such as high diffraction efficiency, wide on/off dynamic range, low optical scatter, low switching voltage and power consumption, high speed, uniformity and repeatability, low cost, and manufacturability. We describe the challenges and progress in meeting many of these goals. C1 USAF, Res Lab, Mat & Mfg Directorate, MLPJ, Wright Patterson AFB, OH 45433 USA. RP Sutherland, RL (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLPJ, Wright Patterson AFB, OH 45433 USA. NR 7 TC 8 Z9 8 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 0-8194-3103-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3633 BP 226 EP 233 DI 10.1117/12.349330 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN29J UT WOS:000081442500024 ER PT S AU Ford, SD Voelz, DG Gamiz, VL Storm, SL Czyzak, SR Oldenettel, J Hunter, A AF Ford, SD Voelz, DG Gamiz, VL Storm, SL Czyzak, SR Oldenettel, J Hunter, A BE Schulz, TJ Idell, PS TI Geo Light Imaging National Testbed (GLINT) - past, present, and future SO DIGITAL IMAGE RECOVERY AND SYNTHESIS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Digital Image Recovery and Synthesis IV CY JUL 20-21, 1999 CL DENVER, CO SP SPIE, Soc Ind & Appl Math DE Fourier telescopy; space surveillance; active imaging; long-baseline interferometry AB Object identification in deep space is a surveillance mission critical to our national defense. Satellite health / status monitoring is another important space surveillance task with both military and civilian applications. Deep space satellites provide challenging targets for ground-based optical sensors due to the extreme range imposed by gee-stationary and geosynchronous orbits. The Air Force Research Laboratory, in partnership with Trex Enterprises and our other contractor partners, will build a new ground-based sensor to address these deficiencies. The Geo Light imaging National Testbed (GLINT) is based on an active imaging concept known as Fourier telescopy. In this technique, the target satellite is illuminated by two or more laser sources. The corresponding fields interfere at the satellite to form interference fringes. These fringes may be made to move across the target by the introduction of a frequency shift between the laser beams. The resulting time-varying laser backscatter contains information about a Fourier component of the target reflectivity and may be collected with a large solar heliostat array. This large unphased receiver provides sufficient signal-to-noise ratio for each Fourier component using relatively low power laser sources. A third laser source allows the application of phase closure in the image reconstruction software. Phase closure removes virtually all low frequency phase distortions and guarantees that the phases of all fringes are relatively fixed. Therefore, the Fourier phase associated with each component can be recovered accurately. This paper briefly reviews the history of Fourier telescopy, the proposed design of the GLINT system, and the future of this research area. C1 USAF, Res Lab, Adv Opt & Imaging Div, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Ford, SD (reprint author), USAF, Res Lab, Adv Opt & Imaging Div, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 18 TC 18 Z9 18 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 0-8194-3301-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3815 BP 2 EP 10 DI 10.1117/12.364119 PG 3 WC Engineering, Multidisciplinary; Mathematics, Applied; Optics SC Engineering; Mathematics; Optics GA BN96J UT WOS:000083674400001 ER PT S AU Lasche, JB Matson, CL Ford, SD Thweatt, WL Rowland, KB Benham, VN AF Lasche, JB Matson, CL Ford, SD Thweatt, WL Rowland, KB Benham, VN BE Schulz, TJ Idell, PS TI Reflective tomography for imaging satellites: experimental results SO DIGITAL IMAGE RECOVERY AND SYNTHESIS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Digital Image Recovery and Synthesis IV CY JUL 20-21, 1999 CL DENVER, CO SP SPIE, Soc Ind & Appl Math DE laser radar; ladar; reflective tomography ID FIELD; LASER AB The Air Force Research Laboratory is in the process of demonstrating an advanced space surveillance capability with a heterodyne laser radar (ladar) system to be used, among other applications, for range-resolved imaging of orbiting satellites. A snail-scale version of this system, the Heterodyne Imaging Laser Testbed (HILT), is used for obtaining pulsed reflection returns from targets that are located on the ground at a distance of similar to 1km. Presented in this paper are a description of HILT and the preliminary results: image reconstructions of the ground targets using reflective tomographic techniques. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Lasche, JB (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 15 TC 4 Z9 4 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 0-8194-3301-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3815 BP 178 EP 188 DI 10.1117/12.364127 PG 3 WC Engineering, Multidisciplinary; Mathematics, Applied; Optics SC Engineering; Mathematics; Optics GA BN96J UT WOS:000083674400017 ER PT S AU Ford, SD Matson, CL AF Ford, SD Matson, CL BE Schulz, TJ Idell, PS TI Projection registration in reflective tomography SO DIGITAL IMAGE RECOVERY AND SYNTHESIS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Digital Image Recovery and Synthesis IV CY JUL 20-21, 1999 CL DENVER, CO SP SPIE, Soc Ind & Appl Math DE reflection tomography; laser radar; phase retrieval; projection registration ID SHORT-PULSELENGTH LASER; OBJECT; SYSTEM; PHASE AB The Air Force Research Laboratory, Directed Energy Directorate, is in the process of demonstrating an advanced space surveillance capability with a heterodyne laser radar system to be used for range-reserved imaging of orbiting satellites. This system, called HI-CLASS (High Performance CO2 Ladar Surveillance Sensor), uses a CO2 laser in a modelocked configuration to generate similar to 10 mu s bursts of similar to 1 ns pulses repeated at a 30 Hz rate. When reflected from an orbiting satellite, these pulses contain information about the range-resolved reflectivities and the Doppler spectrum of the target. For earth-stabilized satellites, cross-range motion is insufficient to produce Doppler-resolved images from the range-resolved data for the HI-CLASS system parameters. However, an image reconstruction method called reflection tomography can be used to reconstruct satellite images by using a tomographic reconstruction approach. An important issue in tomographic image reconstruction is correct registration of the individual projections. For accurate image reconstruction, all projections must be aligned to the target center of rotation. Due to typical system alignment uncertainties, atmospheric fluctuations, and random satellite displacements, range cannot be measured accurately enough to determine the satellite center of rotation. Therefore, this information must be inferred from the projection data itself. Here, we present an algorithm that uses a phase-retrieval approach to determine the required center of rotation from the projection data. We demonstrate the effectiveness of this algorithm using computer-simulated data. We also discuss the future application of this algorithm to actual ladar data. C1 USAF, Res Lab, Adv Opt & Imaging Div, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Ford, SD (reprint author), USAF, Res Lab, Adv Opt & Imaging Div, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 17 TC 9 Z9 9 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 0-8194-3301-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3815 BP 189 EP 198 DI 10.1117/12.364128 PG 4 WC Engineering, Multidisciplinary; Mathematics, Applied; Optics SC Engineering; Mathematics; Optics GA BN96J UT WOS:000083674400018 ER PT J AU Adve, RS Wicks, MC AF Adve, RS Wicks, MC TI Joint domain localized adaptive processing using nonorthogonal steering vectors SO DIGITAL SIGNAL PROCESSING LA English DT Article AB The joint domain localized (JDL) processing adaptive algorithm significantly speeds up space-time adaptive processing by working within a localized processing region in the angle-Doppler domain. The two-dimensional data collected in space and time domains are transformed to the angle-Doppler domain using the spatial and temporal steering vectors. However, the algorithm depends on the assumption that the steering vectors form an orthogonal set. In practice, due to the mutual coupling between antenna elements, the spatial steering vectors are nonorthogonal. This paper presents a modification of the JDL algorithm to account for the nonorthogonality of the spatial steering vectors. The modification is extended to allow for the use of windows in transforming from the space-time to the angle-Doppler domain. Improvements in detection capability are demonstrated using examples from the MCARM database. (C) 1999 Academic Press. C1 USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, Rome, NY 13441 USA. RP Adve, RS (reprint author), USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, 26 Elect Pkwy, Rome, NY 13441 USA. NR 6 TC 0 Z9 0 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1051-2004 J9 DIGIT SIGNAL PROCESS JI Digit. Signal Prog. PD JAN PY 1999 VL 9 IS 1 BP 36 EP 44 DI 10.1006/dspr.1998.0329 PG 9 WC Engineering, Electrical & Electronic SC Engineering GA 179BU UT WOS:000079304300003 ER PT J AU Lemasters, GK Lockey, JE Olsen, DM Selevan, SG Tabor, MW Livingston, GK New, GR AF Lemasters, GK Lockey, JE Olsen, DM Selevan, SG Tabor, MW Livingston, GK New, GR TI Comparison of internal dose measures of solvents in breath, blood and urine and genotoxic changes in aircraft maintenance personnel SO DRUG AND CHEMICAL TOXICOLOGY LA English DT Article; Proceedings Paper CT 1998 Tri-Service/EPA/ATSDR Toxicology Conference on Issues and Applications in Toxicology and Risk Assessment CY APR 27-30, 1998 CL WRIGHT PATTERSON AFB, OHIO SP Air Force Res Lab, Human Effectiveness Directorate, Operat Toxicol ID SISTER-CHROMATID EXCHANGES; OCCUPATIONAL EXPOSURE; LYMPHOCYTES; MICRONUCLEI; FREQUENCIES; TOLUENE; ABERRATIONS; WORKERS AB Solvents and fuels are in widespread use both in civilian and military populations. 1,1,1-trichloroethane (TCA) xylene, toluene, methyl ethyl ketone (MEK) and methylene chloride are found in a variety of compounds including degreasing agents, paints, coatings, pesticides and paint strippers. Toluene and xylene are also found in fuels, which are complex mixtures of hundreds of agents. The purpose of this investigation was twofold. The first was to determine the optimum medium to measure internal close of solvents comparing blood, urine and breath. The second was to determine if low level exposures were associated with genotoxic changes after a short-term exposure of fifteen or thirty weeks. To accomplish the first goal a pilot study was initiated involving eight volunteers who worked in aircraft maintenance including sheetmetal, painting and assembly mechanic jobs. Industrial hygiene measurements were evaluated over 30 working days. Breath, blood and a 24-hour urine sample were collected twice to compare internal dose parameters. To achieve the second Real, 58 newly hired subjects ware monitored prior to exposure and over 30 weeks to determine if there were genotoxic changes as a result of solvent and/or fuel exposure as measured by sister chromatid exchanges (SCEs) and micronuclei (MN). Exposure groups included workers involved in sheetmetal (fuel cell) activities, painting, fueling operations and flight line. Results of the pilot study demonstrated that industrial hygiene air samples and internal breath measures taken an the same day were highly correlated far measuring TCA (r=0.93) and toluene (r=0.90) but was not as well correlated for the other compounds. Breath measures were more sensitive for measuring low level exposure than were either analytes in blood or 24-hour urine samples; these latter two measures were usually below the limit of detection. A small but statistically significant increase in the frequency of SCEs occurred after 30 weeks of exposure for sheet metal workers (p=0.003) and for painters (p=0.05). The MN frequency in the sheet metal workers initially showed a significant increase by 15 weeks, but by 30 weeks had decreased Chance occurrence of exposures to other occupational or non-occupational agents can not be eliminated as a cause of the genotoxic results since between 58 and 93 total analytes could be found in the breath of some aircraft maintenance personnel. C1 Univ Cincinnati, Dept Environm Hlth, Cincinnati, OH 45267 USA. Univ Utah, Huntsman Canc Inst, Salt Lake City, UT 84112 USA. DynCorp Colorado Inc, Dept Occupat Med, Golden, CO USA. USAF, Bolling AFB, Washington, DC 20330 USA. US EPA, Washington, DC 20460 USA. RP Lemasters, GK (reprint author), Univ Cincinnati, Div Epidemiol & Biostat, POB 670056, Cincinnati, OH 45267 USA. FU NIEHS NIH HHS [R01ES06597, ES06096] NR 31 TC 11 Z9 11 U1 0 U2 3 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0148-0545 J9 DRUG CHEM TOXICOL JI Drug Chem. Toxicol. PY 1999 VL 22 IS 1 BP 181 EP 200 PG 20 WC Chemistry, Multidisciplinary; Pharmacology & Pharmacy; Toxicology SC Chemistry; Pharmacology & Pharmacy; Toxicology GA 173RY UT WOS:000078994600014 PM 10189578 ER PT J AU Dawson, D AF Dawson, D TI Cilostazol - A viewpoint SO DRUGS & AGING LA English DT Editorial Material C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. RP Dawson, D (reprint author), Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ADIS INTERNATIONAL LTD PI AUCKLAND PA 41 CENTORIAN DR, PRIVATE BAG 65901, MAIRANGI BAY, AUCKLAND 10, NEW ZEALAND SN 1170-229X J9 DRUG AGING JI Drugs Aging PD JAN PY 1999 VL 14 IS 1 BP 72 EP 73 DI 10.2165/00002512-199914010-00007 PG 2 WC Geriatrics & Gerontology; Pharmacology & Pharmacy SC Geriatrics & Gerontology; Pharmacology & Pharmacy GA 160CQ UT WOS:000078213100007 ER PT B AU Klauenberg, BJ Murphy, MR AF Klauenberg, BJ Murphy, MR BE Bersani, F TI NATO activities as an aid toward international harmonization of EMF standards SO ELECTRICITY AND MAGNETISM IN BIOLOGY AND MEDICINE LA English DT Proceedings Paper CT 2nd World Congress for Electricity and Magnetism in Biology and Medicine CY JUN 08-13, 1997 CL BOLOGNA, ITALY SP Alcatel, Alza, Cent Res Inst Elect Power Ind, Elect Power Res Inst, ENEL, Ericsson, Forsch Gemeinschaft Fnuk e V, IGEA, Motorola, Nokia, Omnitel Pronto Italia, Telecom Italia, Telcom Italia Mobile, USAF, Armstrong Lab, US DOE, Oak Ridge Natl Lab, US Natl Inst Environm Hlth Sci C1 Armstrong Lab, Radiofrequency Radiat Div, Brooks AFB, TX 78235 USA. RP Klauenberg, BJ (reprint author), Armstrong Lab, Radiofrequency Radiat Div, Brooks AFB, TX 78235 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46041-6 PY 1999 BP 81 EP 84 PG 4 WC Biophysics; Multidisciplinary Sciences SC Biophysics; Science & Technology - Other Topics GA BP38D UT WOS:000084928800017 ER PT B AU Adair, ER Kelleher, SA Berglund, LG Mack, GW AF Adair, ER Kelleher, SA Berglund, LG Mack, GW BE Bersani, F TI Physiological and perceptual responses of human volunteers during whole-body RF exposure at 450 MHz SO ELECTRICITY AND MAGNETISM IN BIOLOGY AND MEDICINE LA English DT Proceedings Paper CT 2nd World Congress for Electricity and Magnetism in Biology and Medicine CY JUN 08-13, 1997 CL BOLOGNA, ITALY SP Alcatel, Alza, Cent Res Inst Elect Power Ind, Elect Power Res Inst, ENEL, Ericsson, Forsch Gemeinschaft Fnuk e V, IGEA, Motorola, Nokia, Omnitel Pronto Italia, Telecom Italia, Telcom Italia Mobile, USAF, Armstrong Lab, US DOE, Oak Ridge Natl Lab, US Natl Inst Environm Hlth Sci C1 Armstrong Lab, Brooks AFB, TX 78235 USA. RP Adair, ER (reprint author), Armstrong Lab, Brooks AFB, TX 78235 USA. NR 2 TC 10 Z9 10 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46041-6 PY 1999 BP 613 EP 616 PG 4 WC Biophysics; Multidisciplinary Sciences SC Biophysics; Science & Technology - Other Topics GA BP38D UT WOS:000084928800146 ER PT B AU Ziriax, JM Hatcher, D Belt, ME Roe, J Thomas, A Henry, P Tovias, M D'Andrea, JA AF Ziriax, JM Hatcher, D Belt, ME Roe, J Thomas, A Henry, P Tovias, M D'Andrea, JA BE Bersani, F TI High peak power, low SAR effects on memory task performance in rhesus monkeys SO ELECTRICITY AND MAGNETISM IN BIOLOGY AND MEDICINE LA English DT Proceedings Paper CT 2nd World Congress for Electricity and Magnetism in Biology and Medicine CY JUN 08-13, 1997 CL BOLOGNA, ITALY SP Alcatel, Alza, Cent Res Inst Elect Power Ind, Elect Power Res Inst, ENEL, Ericsson, Forsch Gemeinschaft Fnuk e V, IGEA, Motorola, Nokia, Omnitel Pronto Italia, Telecom Italia, Telcom Italia Mobile, USAF, Armstrong Lab, US DOE, Oak Ridge Natl Lab, US Natl Inst Environm Hlth Sci ID FREQUENCY C1 USAF, Med Res Inst Detachment, Brooks AFB, TX 78235 USA. RP Ziriax, JM (reprint author), USAF, Med Res Inst Detachment, Brooks AFB, TX 78235 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46041-6 PY 1999 BP 621 EP 624 PG 4 WC Biophysics; Multidisciplinary Sciences SC Biophysics; Science & Technology - Other Topics GA BP38D UT WOS:000084928800148 ER PT J AU Sandhu, SS Fellner, JP AF Sandhu, SS Fellner, JP TI Thermodynamic equations for a model lithium-ion cell SO ELECTROCHIMICA ACTA LA English DT Article DE thermodynamics; lithium-ion; model; activity coefficients; battery ID LINIO2; INTERCALATION; GRAPHITE AB Fundamentals of classical thermodynamics of electrochemical systems have been employed to formulate mathematical equations for a model lithium-ion and lithium electrode concentration cell. Equations have been formulated to determine the energetic lithium interaction coefficients in the solid lithium-ion electrode phases and the salt mean activity coefficient in the electrolytic solution used in the model cell from the measured experimental data. In addition, a mathematical equation to predict the open-circuit voltage of the model cell for the case of differing electrolyte compositions in its porous electrodes has been developed. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Dayton, Dept Chem & Mat Engn, Dayton, OH 45469 USA. USAF, Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. RP Sandhu, SS (reprint author), Univ Dayton, Dept Chem & Mat Engn, Dayton, OH 45469 USA. NR 17 TC 0 Z9 0 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PY 1999 VL 45 IS 6 BP 969 EP 976 DI 10.1016/S0013-4686(99)00297-2 PG 8 WC Electrochemistry SC Electrochemistry GA 265UN UT WOS:000084264300015 ER PT B AU Baum, CE AF Baum, CE GP IK IK TI Generalization of the BLT equation SO ELECTROMAGNETIC COMPATIBILITY 1999 LA English DT Proceedings Paper CT 13th International Zurich Symposium and Technical Exhibition on Electromagnetic Compatibility CY FEB 16-18, 1999 CL ZURICH, SWITZERLAND SP Swiss Electrotech Assoc, Swiss Fed Inst Technol, Commun Technol Lab AB The response of a multiconductor transmission line network to electromagnetic excitation is described by the BLT equation. This paper generalizes the BLT equation to include nonuniform multiconductor transmission lines in two different ways. This allows one to model quite general electromagnetic systems in the topological formalism of the BLT equation. C1 USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. RP Baum, CE (reprint author), USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU ETH ZENTRUM-IKT PI ZURICH PA 8092 ZURICH, SWITZERLAND BN 3-9521199-3-8 PY 1999 BP 131 EP 136 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BR53M UT WOS:000166726000026 ER PT B AU Baum, CE Degauque, P Ianoz, M AF Baum, CE Degauque, P Ianoz, M GP EMC EMC TI Progress on modeling EM interaction with complex systems: Applications to aircraft and automobiles SO ELECTROMAGNETIC COMPATIBILITY 1999 SUPPLEMENT - TUTORIAL LECTURES, WORKSHOPS, OPEN MEETINGS AND ADVERTISEMENTS LA English DT Proceedings Paper CT 13th International Zurich Symposium and Technical Exhibition on Electromagnetic Compatibility CY FEB 16-18, 1999 CL ZURICH, SWITZERLAND SP Swiss Electrotech Assoc, Swiss Fed Inst Technol, Commun Technol Lab C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Baum, CE (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU ETH ZENTRUM-IKT PI ZURICH PA 8092 ZURICH, SWITZERLAND BN 3-9521199-4-6 PY 1999 BP 229 EP 230 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA BR53L UT WOS:000166725600027 ER PT S AU Hayduk, MJ Haus, JW Kaechele, W Shaulov, G Teegarden, K Theimer, JP Wicks, GW AF Hayduk, MJ Haus, JW Kaechele, W Shaulov, G Teegarden, K Theimer, JP Wicks, GW BE Pirich, AR Taylor, EW TI Characterization and modeling of a dispersive cavity mode-locked erbium-doped fiber laser SO ENABLING PHOTONIC TECHNOLOGIES FOR AEROSPACE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Photonic Technologies for Aerospace Applications CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE fiber laser; saturable absorber; pulse propagation; optical soliton; mode-locking ID LOCKING AB A novel, compact, polarization insensitive mode-locked erbium-doped fiber laser producing 2 ps pulses was constructed. The laser was passively mode-locked using a 75 period InGaAs/InAlAs multiple quantum well (MQW) saturable absorber grown lattice matched on an InP substrate. The laser was constructed in a linear cavity, Fabry-Perot configuration with the saturable absorber at one end of the cavity and a chirped fiber Bragg grating at the other end. The output pulses are chirped and were further characterized by varying their energies and propagating them down different lengths of standard optical fiber. The laser cavity was modeled using the complex Ginzburg-Landau equation derived under the condition that nonlinear changes to the pulse must be small per round-trip. The contribution of the semiconductor saturable absorber was modeled using a two-level rate equation. The free carrier absorption within the semiconductor contributes to the refractive index which was shown numerically to result in an additional frequency shift. The modeling is in close agreement with the pulse propagation experiments. C1 USAF, Res Lab, Sensors Directorate, Griffiss AFB, NY 13441 USA. RP Hayduk, MJ (reprint author), USAF, Res Lab, Sensors Directorate, 25 Elect Pkwy, Griffiss AFB, NY 13441 USA. NR 9 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 0-8194-3188-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3714 BP 2 EP 11 DI 10.1117/12.354669 PG 10 WC Engineering, Aerospace SC Engineering GA BN70A UT WOS:000082636100001 ER PT S AU Nelson, TR Loehr, JP Xie, QH Ehret, JE Van Nostrand, JE Gamble, L Jones, DK Cole, ST Trimm, RA Diffey, WM Fork, RL Keys, AS AF Nelson, TR Loehr, JP Xie, QH Ehret, JE Van Nostrand, JE Gamble, L Jones, DK Cole, ST Trimm, RA Diffey, WM Fork, RL Keys, AS BE Pirich, AR Taylor, EW TI Electrically tunable group delays using quantum wells in a distributed Bragg reflector SO ENABLING PHOTONIC TECHNOLOGIES FOR AEROSPACE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Photonic Technologies for Aerospace Applications CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE VCSEL arrays; optical beamforming; electrically tunable group delay; quantum-well devices; quantum-confined Stark effect ID BAND-GAP; PROPAGATION AB We present an optical delay line structure incorporating In,Gal.,As quantum wells in the GaAs quarter-wave layers of a GaAs/AlAs distributed Bragg reflector (DBR). Applying an electric field across the quantum wells red shifts and broadens the e1-hh1 exciton peak via the quantum-confined Stark effect (QCSE). Resultant changes in the index of refraction thereby provide a means for altering the group delay of an incident laser pulse. Theoretical results predict tunable delays on the order of 50 fs for a 30-period structure incorporating 3 quantum wells per GaAs layer. Structure design, growth and fabrication are detailed, preliminary group delay measurements on large-area samples with no applied bias are presented. C1 USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Nelson, TR (reprint author), USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. NR 17 TC 2 Z9 2 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 0-8194-3188-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3714 BP 12 EP 23 PG 12 WC Engineering, Aerospace SC Engineering GA BN70A UT WOS:000082636100002 ER PT S AU Thai, S AF Thai, S BE Pirich, AR Taylor, EW TI Bacteriorhodopsin overview of fundamentals and applications SO ENABLING PHOTONIC TECHNOLOGIES FOR AEROSPACE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Photonic Technologies for Aerospace Applications CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE bacteriorhodopsin; organic photopolymer; purple membrane; protein; transient hologram; optical memories ID SCHIFF-BASE; REFRACTIVE-INDEX; FILMS; PHOTOCYCLE; WILDTYPE AB Bacteriorhodopsin (BR) is a light transducing photochromic protein in the purple membrane of a salt-loving microorganism that inhabits salt marshes. It has strong absorption in a broad region of the visible spectrum. The B-state in the photocycle can be considered to be the,ground state, which has absorption maxima at 570 nm, whereas the intermediate M-state has the longest thermal lifetime with its absorption maxima at 413 nm. Perhaps, the most intriguing features of this organic photopolymer are its extraordinary stability in the chemical, thermal and photochemical sense, its large optical nonlinearity, dynamic nature, durability, real-time holographic recording capabilities, and information storage potential. Furthermore, BR-doped polymer film can be fabricated for a large-scale application, whereas photorefractive crystals like BSO or KNSBN cannot be, grown easily to the same dimension as BR. Hence, BR's potential in optical system includes transient dynamic applications of an M-type hologram and three dimensional optical memories of a branched photocycle that shows a great promise for data storage and retrieval due to its high capacity. The major advantages of this organic photopolymer include high density, low cost, low weight and portability which are a projected requirement for the Air Force and commercial applications. C1 USAF, Res Lab, SNDP, Griffiss AFB, NY 13441 USA. RP Thai, S (reprint author), USAF, Res Lab, SNDP, 25 Elect Pkwy, Griffiss AFB, NY 13441 USA. NR 38 TC 2 Z9 2 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 0-8194-3188-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3714 BP 31 EP 37 DI 10.1117/12.354689 PG 7 WC Engineering, Aerospace SC Engineering GA BN70A UT WOS:000082636100004 ER PT S AU Woodyard, JM Jones, J Reif, DC AF Woodyard, JM Jones, J Reif, DC BE Sisti, AF TI Closed loop real-time testing of avionics systems using distributed interactive simulation technology SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Technology for Simulation Science III CY APR 06-08, 1999 CL ORLANDO, FL SP SPIE DE real-time; distributed simulation; hardware-in-the-loop; pilot-in-the-loop; avionics AB The Avionics Wind Tunnel SBIR is a project sponsored by the Air Force Research Laboratory at Wright Patterson with Amherst Systems Inc. The goal was to perform a closed-loop test, stimulating an operational avionics component, capturing its reaction, and injecting it back into the threat simulation. The project integrated several existing and new technologies to evaluate cost-effective methods for performing avionics system evaluation. Distributed Interactive Simulation (DIS) technology was used to interface the system under test (SUT), the ownship platform and the threat environment simulation. The threat environment was provided by two sets of models. One set was designed to serve as a campaign level simulation and provided background signals. The second set of models was considered "medium" fidelity and provided the primary input to the SUT. The data from the two sets of models and data from the ownship was blended and fed into the stimulation equipment that provided RF signals for the SUT. The reaction of the SUT to the stimulation was digitally monitored on a MIL-STD-1553B bus and fed back to the threat models that modified their action. C1 IFST, AFRL, Wright Patterson AFB, OH 45433 USA. RP Woodyard, JM (reprint author), IFST, AFRL, 2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 3 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 0-8194-3170-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3696 BP 54 EP 61 DI 10.1117/12.351197 PG 8 WC Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BN40J UT WOS:000081823700005 ER PT S AU Plotz, GA Karle, TA AF Plotz, GA Karle, TA BE Sisti, AF TI A benchmark problem for model abstraction techniques SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Technology for Simulation Science III CY APR 06-08, 1999 CL ORLANDO, FL SP SPIE DE metamodel; model abstraction; TERSM; factorial design; regression analysis AB Modeling of real systems relies on the arduous task of describing the physical phenomena in terms of mathematical models, which often require excessive amounts of computation time in their execution. In the last few years there has been a growing acceptance of model abstraction whose emphasis rests on the development of more manageable models. Abstraction refers to the intelligent capture of the essence of the behavior of a model, without all the details. In the past, metamodels have been generated from complex models, such as the Tactical Electronic Reconnaissance Simulation Model (TERSM). The scope of this paper is to explore the ability of previously developed TERSM metamodels to accurately simulate the benchmark model using both Limited subsets of the original data, and data subsets whose values are interpolated or extrapolated from the original data set used to generate and fit the model. This paper establishes a baseline from which additional metamodels can be compared and analyzed. C1 USAF, Res Lab, Rome, NY 13441 USA. RP Plotz, GA (reprint author), USAF, Res Lab, 525 Brooks Rd, Rome, NY 13441 USA. NR 4 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 0-8194-3170-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3696 BP 96 EP 102 DI 10.1117/12.351167 PG 7 WC Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BN40J UT WOS:000081823700009 ER PT S AU Moore, J AF Moore, J BE Sisti, AF TI Advanced displays for modeling and simulation SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Technology for Simulation Science III CY APR 06-08, 1999 CL ORLANDO, FL SP SPIE DE Java; 3D; visualization; rapid prototyping AB Is the Java 3D API able to support the visualization requirements of a complex Modeling and Simulation environment for the next generation of Collaborative Command and Control applications? As a simple test of its functionality a demonstration application will be programmed to create a terrain, populate it with a number of primitive objects (Radar, airplanes, etc..), and allow the user to navigate through the terrain. C1 USAF, Res Lab, Rome, NY 13441 USA. RP Moore, J (reprint author), USAF, Res Lab, Rome Res Site, Rome, NY 13441 USA. NR 1 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 0-8194-3170-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3696 BP 213 EP 219 DI 10.1117/12.351179 PG 7 WC Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BN40J UT WOS:000081823700020 ER PT S AU Pflug, DR AF Pflug, DR BE Sisti, AF TI Phenomenological modeling and simulation in support of model abstraction: computational electromagnetics - an overview SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Enabling Technology for Simulation Science III CY APR 06-08, 1999 CL ORLANDO, FL SP SPIE DE model abstraction; modeling; simulation; computational electromagnetics; phenomenology AB Successful modeling and simulation of Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) systems requires not only the inclusion of the relevant C4ISR processes involved in the problem under study but also inclusion of the physics behind some of the simulation objects. The electromagnetic performance of the various sensors present in the simulation and the electromagnetic effects caused by the platforms on which the sensors reside are examples. The physical science necessary to simulate such physical effects is called Computational Electromagnetics (CEM) and can provide high quality performance data capable of enhancing the accuracy and value of C4ISR simulations. Unfortunately the simulation of these effects from first principles cannot be done in even near real time. Model Abstraction needs to be applied to such phenomenological simulations to extract out data of the required accuracy in reasonable simulation time. This paper reviews state-of-the-art CEM with a view towards stimulating the development of those Model Abstraction techniques required to incorporate CEM phenomenology into the C4ISR modeling and simulation world. C1 USAF, Res Lab, Rome, NY 13441 USA. RP USAF, Res Lab, Rome, NY 13441 USA. NR 14 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 0-8194-3170-2 J9 PROC SPIE PY 1999 VL 3696 BP 302 EP 313 DI 10.1117/12.351189 PG 12 WC Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BN40J UT WOS:000081823700029 ER PT S AU Pflug, DR Karle, TA AF Pflug, DR Karle, TA BE Sisti, AF TI Model based parameter estimation and related methods as model abstraction techniques in computational electromagnetics SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Technology for Simulation Science III CY APR 06-08, 1999 CL ORLANDO, FL SP SPIE DE approximation techniques; parameter identification; model reduction; estimation ID BAND INFORMATION; ACCURATE AB It is demonstrated that the technique of Model Based Parameter Estimation (MBPE), specifically Cauchy's Method, can be used in the frequency domain to extrapolate/interpolate a narrowband set of system data or information to a broadband set of data or information. The information can be either computed or measured data over a frequency band. For computed data the sampled values of the function and a few derivative values can be used to reconstruct the function. For measured data only sampled values of the function are used as derivative values are too noisy. Cauchy's method is based on applying the principle of analytic continuation to a complex, hard to specify function, analytic except at isolated poles, that represents the frequency domain property of interest. Such a function can be represented by a ratio of two polynomials, a reduced order model, which can be considered to be a variant of model abstraction (3). A procedure is outlined for determining the order of the polynomials and their coefficients using the methods of Singular Value Decomposition (SVD) and Total Least Squares. The method is applied to a selected set of frequency domain problems to illustrate the accuracy and versatility of the method. C1 USAF, Res Lab, Rome, NY 13441 USA. RP Pflug, DR (reprint author), USAF, Res Lab, Rome, NY 13441 USA. NR 8 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 0-8194-3170-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3696 BP 314 EP 321 DI 10.1117/12.351190 PG 8 WC Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BN40J UT WOS:000081823700030 ER PT S AU Vaccaro, JM Yaworsky, PS AF Vaccaro, JM Yaworsky, PS BE Sisti, AF TI Real-time modeling of primitive environments through wavelet sensors and hebbian learning SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enabling Technology for Simulation Science III CY APR 06-08, 1999 CL ORLANDO, FL SP SPIE DE hebbian learning; integrate and fire neurons; temporal coding; wavelets; self-organized networks AB Modeling the world through sensory input necessarily provides a unique perspective for the observer. Given a limited perspective, objects and events cannot always be encoded precisely but must involve crude, quick approximations to deal with sensory information in a real-time manner. As an example, when avoiding an oncoming car, a pedestrian needs to identify the fact that a car is approaching before ascertaining the model or color of the vehicle. In our methodology, we use wavelet-based sensors with self-organized learning to encode basic sensory information in real-time. The wavelet-based sensors provide necessary transformations while a rank-based Hebbian learning scheme encodes a self-organized environment through translation, scale and orientation invariant sensors. Such a self-organized environment is made possible by combining wavelet sets which are orthonormal, log-scale with linear orientation and have automatically generated membership functions. In earlier work we used Gabor wavelet filters, rank-based Hebbian learning and an exponential modulation function to encode textural information from images. Many different types of modulation are possible, but based on biological findings the exponential modulation function provided a good approximation of first spike coding of "integrate and fire" neurons. These types of Hebbian encoding schemes (e.g., exponential modulation, etc.) are useful for quick response and learning, provide several advantages over contemporary neural network learning approaches, and have been found to quantize data nonlinearly. By combining wavelets with Hebbian learning we can provide a real-time front-end for modeling an intelligent process, such as the autonomous control of agents in a simulated environment. C1 USAF, Res Lab, Rome, NY 13441 USA. RP Vaccaro, JM (reprint author), USAF, Res Lab, 525 Brooks Rd, Rome, NY 13441 USA. 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 0-8194-3170-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3696 BP 331 EP 338 DI 10.1117/12.351188 PG 8 WC Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BN40J UT WOS:000081823700032 ER PT B AU Garrett, CA Huang, JQ Goltz, MN AF Garrett, CA Huang, JQ Goltz, MN BE Leeson, A Alleman, BC TI Optimization of in situ bioremediation of trichloroethylene using genetic algorithms SO ENGINEERED APPROACHES FOR IN SITU BIOREMEDIATION OF CHLORINATED SOLVENT CONTAMINATION LA English DT Proceedings Paper CT 5th International In Situ and On-Site Bioremediation Symposium CY APR 19-22, 1999 CL SAN DIEGO, CA SP Battelle Mem Inst, Gas Res Inst, IT Grp Inc, Celtic Technol, Parsons Engn Sci Inc, U S Microb Inc, U S Naval Fac Engn Command, Waste Management Inc ID CHLORINATED ALIPHATICS; INSITU BIORESTORATION; MODEL SIMULATIONS AB A recent field evaluation of in situ aerobic cometabolic bioremediation demonstrated that this technology has promise to be an inexpensive and effective alternative to current technologies for the remediation of trichloroethylene (TCE)-contaminated groundwater. A fate and transport model has been developed to simulate the relevant processes that affect TCE fate and transport during technology application. Implementation of the technology requires that designers understand how to adjust engineered parameters in order to optimize system performance. While the fate and transport model can provide system performance information, the complexity of the system and the number of engineered parameters that can be varied make determining an optimal design problematic. Genetic algorithms may be used to determine those design parameter values that optimize the performance of this complex treatment system. By applying genetic algorithms, we hope to gain a better understanding of the technology, and ultimately, learn how to better design and implement in situ aerobic cometabolic biotreatment systems. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Garrett, CA (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-075-6 PY 1999 BP 275 EP 280 PG 6 WC Environmental Sciences SC Environmental Sciences & Ecology GA BN62Y UT WOS:000082416100043 ER PT J AU Kwon, O Nikbin, KM Webster, GA Jata, KV AF Kwon, O Nikbin, KM Webster, GA Jata, KV TI Crack growth in the presence of limited creep deformation SO ENGINEERING FRACTURE MECHANICS LA English DT Article; Proceedings Paper CT VAMAS Working Group 19 Meeting CY OCT, 1996 CL GEORGIA INST TECHNOL, ATLANTA, GEORGIA SP Varsailles Agreement Adv Mat Stand Working Grp 19 HO GEORGIA INST TECHNOL DE creep; crack growth; test methods ID HIGH-TEMPERATURE CREEP; PREDICTION AB Creep crack growth tests have been conducted on a plain carbon manganese steel, aluminium alloy 2519 and titanium alloy 6242 at 360, 135 and 500 degrees C, respectively, at conditions where only limited creep deformation was observed. The results have been analysed using ASTM Standard E1457-92 which was developed for describing creep crack growth in the presence of extensive creep. It has been found that the creep fracture mechanics parameter C* defined in E1457 can also be used to interpret the data generated in this investigation but that it is necessary for certain restrictions imposed in the Standard to be relaxed to allow the data to be assessed. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ London Imperial Coll Sci Technol & Med, Dept Mech Engn, London SW7 2BX, England. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Kwon, O (reprint author), Univ London Imperial Coll Sci Technol & Med, Dept Mech Engn, London SW7 2BX, England. NR 21 TC 10 Z9 10 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-7944 J9 ENG FRACT MECH JI Eng. Fract. Mech. PD JAN PY 1999 VL 62 IS 1 BP 33 EP 46 DI 10.1016/S0013-7944(98)00081-2 PG 14 WC Mechanics SC Mechanics GA 180JG UT WOS:000079382000004 ER PT J AU Holzhauer, D Grosse, I AF Holzhauer, D Grosse, I TI Finite element analysis using component decomposition and knowledge-based control SO ENGINEERING WITH COMPUTERS LA English DT Article DE blackboard architecture; component decomposition; knowledge-based control; transient finite element analysis AB This paper presents ongoing research into using Artificial Intelligence (AI) techniques to intelligently control finite element thermal analyses. These techniques are used to implement component level decomposition of the physical domain, and to integrate domain information into the analysis process to increase computational efficiency. We have implemented these techniques into a new proof-of-concept finite element program which employs a blackboard architecture to integrate the various numerical and symbolic knowledge sources. The blackboard architecture also supports the storage (and retrieval) of data in an object-oriented form. A test problem involving transient thermal analysis of an integrated circuit package is presented. Use of the proposed method showed a significant decrease in the number of floating point operations required compared to conventional solution technologies. The penalty associated with this saving was approximately a 4% difference in the calculated temperature in the critical region of interest. C1 USAF, Res Lab, IFTC, Rome, NY 13441 USA. Univ Massachusetts, Dept Mech & Ind Engn, Amherst, MA 01003 USA. RP Holzhauer, D (reprint author), USAF, Res Lab, IFTC, 26 Elect Pkwy, Rome, NY 13441 USA. NR 10 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0177-0667 J9 ENG COMPUT JI Eng. Comput. PY 1999 VL 15 IS 4 BP 315 EP 325 DI 10.1007/s003660050026 PG 11 WC Computer Science, Interdisciplinary Applications; Engineering, Mechanical SC Computer Science; Engineering GA 282CP UT WOS:000085199000002 ER PT S AU Brooks, G AF Brooks, G BE Verly, JG TI Coarse coding in natural and artificial vision systems SO ENHANCED AND SYNTHETIC VISION 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Enhanced and Synthetic Vision 1999 CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE coarse coding; broadband filters; vision processing; vision filters; vision models; early vision ID SENSORY INFORMATION; REPRESENTATION AB Coarse-coding is the transformation of raw data using a small number of broadly overlapping filters. These filters may exist in time, space, color, or other information domains. Inspired by models of natural vision processing, intensity and color information has been previously encoded and successfully decoded using coarse coding(1). The color and intensity of objects within test images were successfully retrieved after passing through only two coarse filters arranged in a checkerboard fashion. It was shown that a consequence of such a filter is a natural edge enhancement of the objects within the image. Coarse-coding is considered here in a signal processing frequency domain and in a sensory spectral filtering domain. Test signals include single frequency, multiple frequency, and signals with broad frequency content. Gaussian-based filters are used to discriminate between different signals of arbitrary frequency content The effects of Gaussian shape changes and spectral contrasting techniques are demonstrated. Consequences in filter parameter selection are further discussed. C1 USAF, Adv Guidance Div, RL Munit Directorate, Eglin AFB, FL 32542 USA. RP Brooks, G (reprint author), USAF, Adv Guidance Div, RL Munit Directorate, Eglin AFB, FL 32542 USA. NR 26 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 0-8194-3165-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3691 BP 157 EP 166 DI 10.1117/12.354426 PG 10 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Civil SC Automation & Control Systems; Engineering GA BN68R UT WOS:000082586300016 ER PT B AU Campbell, RK Freedman, DL Kim, BJ AF Campbell, RK Freedman, DL Kim, BJ BE Schafran, GC TI Treatment of nitrocellulose by thermal decomposition SO ENVIRONMENTAL ENGINEERING 1999 LA English DT Proceedings Paper CT ASCE-CSCE National Conference on Environmental Engineering CY JUL 25-28, 1999 CL NORFOLK, VA SP Amer Soc Civil Engineers, Div Environm Engn, Canadian Soc Civil Engn, Div Environm Engn, US EPA, URS Greiner Woodward Clyde, Amer Soc Civil Engineers, Norfolk Branch, Hampton Roads Sanitat Dist, City Norfolk Dept Utilit, Environm Assessment Assoc, Int Eros Control Assoc, Natl Onsite Wastewater Recycling Assoc, SE Public Serv Authority, USN, Old Dominion Univ AB Waste fines generated during the manufacture of nitrocellulose (NC) are classified as a RCRA K044 hazardous waste due to their explosive properties. The objective of this study was to evaluate controlled thermal treatment of NC in order to render it nonhazardous and allow for more economical ultimate disposal. The results indicate that controlled thermal decomposition at 130-150 degrees C is a technically feasible process. Rates improved significantly at higher temperatures. At 150 degrees C, only 10 hours were needed to reduce the nitrogen content of NC from 13.7% to below 10% (versus 105 h at 130 degrees C), a revel found in many commercial, nonhazardous grades of NC. The air flow rats over the heated NC, and the moisture content of the NC or air above it had no discernible effect on rates of nitrogen removal. Greater mass loss from the NC than what was attributable to the nitro groups alone indicated that decomposition of the poll;mer backbone also occurred. This was confirmed by FTIR analyses, the appearance of CO2 in the off-gas, and a lack of correlation between percent nitrogen and heat of combustion Samples of thermally treated NC containing 9.7% nitrogen failed three of the basic tests used by the Bureau of Explosives to ascertain explosive characteristics, indicating that the product was no longer hazardous based on its energetic properties. Although technically feasible, use of thermal decomposition to treat NC fines will most likely be restricted by safety concerns. Operating close to 130 degrees C would mitigate the risk, but considerably extends the time required for treatment. The most suitable application of this technology may instead he treatment of NC-contaminated soils. C1 Davis Monthan AFB, Davis Monthan AFB, AZ 85707 USA. RP Campbell, RK (reprint author), Davis Monthan AFB, Davis Monthan AFB, AZ 85707 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU AMER SOC CIVIL ENGINEERS PI NEW YORK PA UNITED ENGINEERING CENTER, 345 E 47TH ST, NEW YORK, NY 10017-2398 USA BN 0-7844-0435-6 PY 1999 BP 246 EP 253 PG 8 WC Engineering, Environmental; Engineering, Civil SC Engineering GA BP85T UT WOS:000086435900026 ER PT S AU Eastwood, D Martin, JB Burggraf, LW Rand, DS Zickafoose, MS Perry, DL AF Eastwood, D Martin, JB Burggraf, LW Rand, DS Zickafoose, MS Perry, DL BE VoDinh, T Spellicy, RL TI Photoluminescence and vibrational spectroscopic studies on weathered uranium oxides SO ENVIRONMENTAL MONITORING AND REMEDIATION TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Environmental Monitoring and Remediation Technologies CY NOV 02-05, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers DE uranium oxides; weathering; photoluminescence; Fourier transform infrared spectroscopy (FTIR); diffuse reflectance infrared; phosphorescence ID URANYL COMPLEXES; LUMINESCENCE; ION AB Spectroscopic studies were performed both on uranium oxides as baseline and on uranium oxides artificially weathered under known laboratory conditions in air, varying humidity, carbon dioxide concentration, temperature and exposure to UV light. Spectroscopic techniques included photoluminescence and diffuse reflectance FTIR. Photoluminescence measurements were made using a Spex Fluorolog-3(TM) spectrofluorometer with phosphorimeter. FTIR measurements were made using a Bomem MB 157 FTIR spectrophotometer with DTGS detector and approximately 450 cm(-1) cut-off and a Graseby Selector(TM) diffuse reflectance accessory with special cells and diamond dust as diluent and internal standard. Weathered-related reactions involving the uranium oxides that have been studied include oxidation and the formation of hydroxides and carbonates. Data are discussed with respect to both the reactions of the uranium oxides in the study and in context of reaction chemistry and mechanisms that have been previously documented. The results will be discussed in the context of environmental monitoring. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Eastwood, D (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 24 TC 0 Z9 0 U1 1 U2 3 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2995-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3534 BP 487 EP 495 DI 10.1117/12.339031 PG 9 WC Engineering, Environmental; Environmental Sciences; Instruments & Instrumentation; Optics SC Engineering; Environmental Sciences & Ecology; Instruments & Instrumentation; Optics GA BM82B UT WOS:000079845100052 ER PT J AU Stager, MP Perram, GP AF Stager, MP Perram, GP TI Long-term desorption of trichloroethylene from flint clay using multiplexed optical detection SO ENVIRONMENTAL POLLUTION LA English DT Article DE trichloroethylene; desorption; kinetics; optical detection; soil ID VOLATILE ORGANIC-COMPOUNDS; CONTAMINATED SOILS; AQUIFER MATERIAL; SORPTION; KINETICS AB The long-term desorption of trichloroethylene (TCE) from powdered flint clay was examined using a multiplexed, phase sensitive infrared technique which provided a gas phase detection limit of 0.0045 torr for continuous monitoring of the desorption process for at least 3 days. The vapor phase TCE concentrations as a function of desorption time exhibit a significant deviation from Langmuir kinetics. The desorption process is adequately described by bonding sites with a gamma distribution for the desorption rate coefficients. The mean desorption rate for powdered flint clay at 25 degrees C is k(d) = 0.50 +/- 0.02 h(-1). Published by Elsevier Science Ltd. C1 USAF, Inst Technol, ENP, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Perram, GP (reprint author), USAF, Inst Technol, ENP, Dept Engn Phys, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. OI Perram, Glen/0000-0002-4417-3929 NR 14 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0269-7491 J9 ENVIRON POLLUT JI Environ. Pollut. PY 1999 VL 104 IS 3 BP 397 EP 400 DI 10.1016/S0269-7491(98)00181-X PG 4 WC Environmental Sciences SC Environmental Sciences & Ecology GA 159MZ UT WOS:000078178700009 ER PT S AU Mahalingam, K Dorsey, DL Taferner, WT Eyink, KG AF Mahalingam, K Dorsey, DL Taferner, WT Eyink, KG BE Barabasi, AL Krishnamurthy, M Liu, F Pearsall, T TI A kinetic Monte Carlo model for Ga desorption from chemisorbed and physisorbed states during high temperature GaAs MBE SO EPITAXIAL GROWTH-PRINCIPLES AND APPLICATIONS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Epitaxial Growth-Principles and Applications CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc ID MOLECULAR-BEAM EPITAXY; GALLIUM DESORPTION; SIMULATIONS; GROWTH AB A kinetic Monte Carlo model is developed to examine the influence of As/Ga flux ratio on the Ga desorption kinetics during molecular beam epitaxy of(100)-GaAs, based on data reported in desorption mass spectrometry experiments, A good match to experimental results is obtained when a mechanism involving desorption from a physisorbed state is included, in addition to desorption from a chemisorbed state. Analysis of the results revealed that the dependence of the Ga desorption energy on the As/Ga flux ratio, observed in growth experiments, is explained in terms of the component due to desorption from the physisorbed state. The Ga desorption energy associated with the chemisorbed state is independent of the As/Ga flux ratio. These predictions are similar to results reported in a recent study of In desorption during molecular beam epitaxy of InGaAs. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Mahalingam, K (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-477-7 J9 MATER RES SOC SYMP P PY 1999 VL 570 BP 85 EP 90 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA BN69F UT WOS:000082591100012 ER PT B AU Lang, M AF Lang, M BE Wu, XR Wang, ZG TI Using the parameter K-PR for life prediction in metals under variable amplitude loading SO FATIGUE '99: PROCEEDINGS OF THE SEVENTH INTERNATIONAL FATIGUE CONGRESS, VOLS 1-4 LA English DT Proceedings Paper CT 7th International Fatigue Congress (Fatigue '99) CY JUN 08-12, 1999 CL Beijing, PEOPLES R CHINA SP Beijing Inst Aeronaut Mat, Inst Met Res, Fatigue Soc, C-MRS, Int Fatigue Congress, Nat Sci Fdn China, C-MRS, MTS Syst Corp, INSTRON Int Ltd, AFOSR AOARD, USARO-FE, Roell Amsler, NCode Int Ltd, United Technol Corp, European Commiss, European Union-Delegat AB The bases of a new crack growth prediction model that separates the crack face contact processes behind the crack tip (crack closure) and the processes in front of the crack tip (residual compressive stresses) are discussed. Crack closure is qualified as an extrinsic effect and residual compressive stresses ahead of the crack front as intrinsic. The approach uses the DeltaK(eff) concept, but a different phenomenological explanation than the one given by Elber involving the crack propagation stress intensity factor, K-PR, is proposed. K-PR is crucial for the evaluation of the intrinsic response of the material to cyclic loading and its significance is outlined. The conceptual handling of the model is demonstrated using experimental results of two different engineering alloys. C1 USAF, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Lang, M (reprint author), USAF, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU CHINA HIGHER EDUCATION PRESS BEIJING PI BEIJING PA 55 SHATAN HOUJIE, BEIJING, PEOPLES R CHINA BN 7-04-007582-2 PY 1999 BP 1033 EP 1038 PG 6 WC Engineering, Mechanical SC Engineering GA BR59R UT WOS:000166896200153 ER PT B AU Lykins, C Mall, S AF Lykins, C Mall, S BE Wu, XR Wang, ZG TI High cycle fretting fatigue behavior of Ti-6Al-4V SO FATIGUE '99: PROCEEDINGS OF THE SEVENTH INTERNATIONAL FATIGUE CONGRESS, VOLS 1-4 LA English DT Proceedings Paper CT 7th International Fatigue Congress (Fatigue '99) CY JUN 08-12, 1999 CL Beijing, PEOPLES R CHINA SP Beijing Inst Aeronaut Mat, Inst Met Res, Fatigue Soc, C-MRS, Int Fatigue Congress, Nat Sci Fdn China, C-MRS, MTS Syst Corp, INSTRON Int Ltd, AFOSR AOARD, USARO-FE, Roell Amsler, NCode Int Ltd, United Technol Corp, European Commiss, European Union-Delegat ID MECHANICS AB Plain fatigue data for Ti-6Al-4V exhibits a dependence on mean stress when plotted as a function of stress amplitude. However bulk fretting fatigue data suggests that this alloy is independent of mean stress effects when plotted as a function of stress or strain amplitude. This phenomenon was investigated by creating a range of fretting fatigue failures through axial mean stress variation. The experimental conditions were then simulated via the finite element technique. The Manson-Coffin relationship was found to be as effective as the Smith-Watson-Topper model in collapsing the fretting fatigue data. This indicates that the local strain amplitude at the trailing edge of contact is a driving parameter for crack nucleation and propagation in fretting fatigue. Furthermore the magnitude of this strain amplitude does not vary significantly as the average coefficient of friction changes from f(avg)=.45 to f(avg)=.75. C1 USAF, Propuls Directorate, Washington, DC 20330 USA. RP Lykins, C (reprint author), USAF, Propuls Directorate, Washington, DC 20330 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU CHINA HIGHER EDUCATION PRESS BEIJING PI BEIJING PA 55 SHATAN HOUJIE, BEIJING, PEOPLES R CHINA BN 7-04-007582-2 PY 1999 BP 1353 EP 1358 PG 6 WC Engineering, Mechanical SC Engineering GA BR59R UT WOS:000166896200205 ER PT B AU Larsen, JM Rosenberger, AH Li, K Porter, WJ John, R AF Larsen, JM Rosenberger, AH Li, K Porter, WJ John, R BE Wu, XR Wang, ZG TI Tailoring TiAl intermetallic alloys to satisfy damage tolerance requirements for high performance turbine engines SO FATIGUE '99: PROCEEDINGS OF THE SEVENTH INTERNATIONAL FATIGUE CONGRESS, VOLS 1-4 LA English DT Proceedings Paper CT 7th International Fatigue Congress (Fatigue '99) CY JUN 08-12, 1999 CL Beijing, PEOPLES R CHINA SP Beijing Inst Aeronaut Mat, Inst Met Res, Fatigue Soc, C-MRS, Int Fatigue Congress, Nat Sci Fdn China, C-MRS, MTS Syst Corp, INSTRON Int Ltd, AFOSR AOARD, USARO-FE, Roell Amsler, NCode Int Ltd, United Technol Corp, European Commiss, European Union-Delegat ID TITANIUM ALUMINIDES AB Gamma titanium aluminide intermetallic alloys offer major weight savings as replacement materials for the more conventional alloys used in today's advanced turbine engines. However, to fully utilize the potential of gamma alloys in fracture critical structural applications, an unprecedented capability for life prediction under demanding service conditions is required. Key issues in fatigue crack nucleation and growth are discussed, emphasizing the role of relevant microstructural features on crack-size effects in this class of alloys. C1 USAF, Mat & Mfg Directorate, AFRL MLLN, Wright Patterson AFB, OH 45433 USA. RP Larsen, JM (reprint author), USAF, Mat & Mfg Directorate, AFRL MLLN, Wright Patterson AFB, OH 45433 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU CHINA HIGHER EDUCATION PRESS BEIJING PI BEIJING PA 55 SHATAN HOUJIE, BEIJING, PEOPLES R CHINA BN 7-04-007582-2 PY 1999 BP 1559 EP 1566 PG 8 WC Engineering, Mechanical SC Engineering GA BR59R UT WOS:000166896200237 ER PT B AU John, R DeLuca, D Porter, WJ Rosenberger, AH AF John, R DeLuca, D Porter, WJ Rosenberger, AH BE Wu, XR Wang, ZG TI Mixed mode crack growth in a gamma titanium aluminide SO FATIGUE '99: PROCEEDINGS OF THE SEVENTH INTERNATIONAL FATIGUE CONGRESS, VOLS 1-4 LA English DT Proceedings Paper CT 7th International Fatigue Congress (Fatigue '99) CY JUN 08-12, 1999 CL Beijing, PEOPLES R CHINA SP Beijing Inst Aeronaut Mat, Inst Met Res, Fatigue Soc, C-MRS, Int Fatigue Congress, Nat Sci Fdn China, C-MRS, MTS Syst Corp, INSTRON Int Ltd, AFOSR AOARD, USARO-FE, Roell Amsler, NCode Int Ltd, United Technol Corp, European Commiss, European Union-Delegat AB This paper describes the results of an investigation of mixed mode (mode I and mode II) loading on the crack growth behavior of a gamma titanium aluminide (TiAl) alloy. A centrally notched disk specimen was used, and the tests were conducted at room temperature. Mixed mode loading conditions were achieved by orienting the machined flaw at different angles to the loading axis. A specimen with large (approximate to5 mm) grains was used to characterize the interlamellar growth under mixed mode loading conditions. Preliminary results indicate that the interlamellar mixed mode crack growth rate is approximate to 10-100X faster than the transgranular mode I crack growth rate in a gamma TiAl and is also associated with a significantly lower DeltaK(th). C1 USAF, Mat & Mfg Directorate, AFRL, MLLN, Wright Patterson AFB, OH 45433 USA. RP John, R (reprint author), USAF, Mat & Mfg Directorate, AFRL, MLLN, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU CHINA HIGHER EDUCATION PRESS BEIJING PI BEIJING PA 55 SHATAN HOUJIE, BEIJING, PEOPLES R CHINA BN 7-04-007582-2 PY 1999 BP 1567 EP 1572 PG 6 WC Engineering, Mechanical SC Engineering GA BR59R UT WOS:000166896200238 ER PT B AU Fawaz, S Lo, J Hsu, C AF Fawaz, S Lo, J Hsu, C BE Wu, XR Wang, ZG TI Equivalent initial flaw size distribution in fuselage skin splices SO FATIGUE '99: PROCEEDINGS OF THE SEVENTH INTERNATIONAL FATIGUE CONGRESS, VOLS 1-4 LA English DT Proceedings Paper CT 7th International Fatigue Congress (Fatigue '99) CY JUN 08-12, 1999 CL Beijing, PEOPLES R CHINA SP Beijing Inst Aeronaut Mat, Inst Met Res, Fatigue Soc, C-MRS, Int Fatigue Congress, Nat Sci Fdn China, C-MRS, MTS Syst Corp, INSTRON Int Ltd, AFOSR AOARD, USARO-FE, Roell Amsler, NCode Int Ltd, United Technol Corp, European Commiss, European Union-Delegat AB The equivalent initial flaw size (EIFS) distribution and growth of small cracks in four spliced panel configurations representative of transport aircraft fuselage lap joints was investigated as part of the FAA contract on Widespread Fatigue Damage Evaluation for aging aircraft. In situ sub-surface crack growth detection and measurement was accomplished using a rotating self-nulling eddy current probe system. Fractographic examination using the scanning electron microscope was employed to determine the crack initiation site, crack shape, and crack history. Corner cracks predominately nucleated at the intersection of the straight portion of the countersunk rivet hole and faying surface. Surface cracks were found which nucleated close to the rivet hole at the faying surface. Once the cracks grew through the sheet thickness, they propagated with part-elliptical crack fronts. The EIFS was determined using FASTRAN and AFGROW. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Fawaz, S (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU CHINA HIGHER EDUCATION PRESS BEIJING PI BEIJING PA 55 SHATAN HOUJIE, BEIJING, PEOPLES R CHINA BN 7-04-007582-2 PY 1999 BP 2551 EP 2556 PG 6 WC Engineering, Mechanical SC Engineering GA BR59R UT WOS:000166896200388 ER PT B AU Lincoln, JW AF Lincoln, JW BE Wu, XR Wang, ZG TI Significant fatigue cracking experiences in the USAF SO FATIGUE '99: PROCEEDINGS OF THE SEVENTH INTERNATIONAL FATIGUE CONGRESS, VOLS 1-4 LA English DT Proceedings Paper CT 7th International Fatigue Congress (Fatigue '99) CY JUN 08-12, 1999 CL Beijing, PEOPLES R CHINA SP Beijing Inst Aeronaut Mat, Inst Met Res, Fatigue Soc, C-MRS, Int Fatigue Congress, Nat Sci Fdn China, C-MRS, MTS Syst Corp, INSTRON Int Ltd, AFOSR AOARD, USARO-FE, Roell Amsler, NCode Int Ltd, United Technol Corp, European Commiss, European Union-Delegat AB The structural failures in commercial and military aircraft have been the primary factors for rules and specifications governing aircraft design. In many cases, the failures have identified threats to structural integrity that were previously unknown to the certification authorities. In many cases, the commercial failures have influenced the military specifications, and the military failures have influenced the commercial aircraft rules. This paper discusses the implications of military and commercial failures and illustrates the evolution of structural criteria for future United States Air Force (USAF) procurements. C1 USAF, Aeronaut Syst Ctr, Washington, DC 20330 USA. RP Lincoln, JW (reprint author), USAF, Aeronaut Syst Ctr, Washington, DC 20330 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU CHINA HIGHER EDUCATION PRESS BEIJING PI BEIJING PA 55 SHATAN HOUJIE, BEIJING, PEOPLES R CHINA BN 7-04-007582-2 PY 1999 BP 2563 EP 2570 PG 8 WC Engineering, Mechanical SC Engineering GA BR59R UT WOS:000166896200390 ER PT S AU Lang, M Marci, G AF Lang, M Marci, G BE Panontin, TL Sheppard, SD TI Reflecting on the mechanical driving force of fatigue crack propagation SO FATIGUE AND FRACTURE MECHANICS: TWENTY-NINTH VOLUME SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 29th National Symposium on Fatigue and Fracture Mechanics CY JUN 24-26, 1997 CL STANFORD, CA SP ASTM Comm E8 Fatigue & Fracture DE fatigue crack propagation; crack closure; residual compressive stresses; Delta K-eff concept; overload effect; load interaction effects; life prediction ID DELTA-K-EFF; THRESHOLD; CLOSURE AB The goal of the work to be presented is a fracture mechanics methodology the description of fatigue crack propagation (FCP) in which the mechanical driving force has a unique relation to FCP. A review of FCP literature leads to two basic premises FCP, namely that a) Delta K indirectly describes the stress and strain excursions in the plastic zone, and b) tensile stresses and strains in the near crack front region are a nec condition for FCP. It is shown that closure as defined by Elber can only act like externally applied tensile load. Therefore, closure cannot be the mechanism that transfer the external cyclic loading condition to the mechanical driving force. A model is proposed which includes the closure mechanism, but the transfer from external cyclic loading to the mechanical driving force is solely due to the stresses and strains in th plastic zone ahead of the crack front, as originally proposed by Schijve. The st intensity factor at which the stresses and strains in the near crack front region switch compression to tension during the loading part of a cycle has been experimentally determined for various cyclic loading conditions. This level is denoted as K-PR the crack propagation stress intensity factor, and allows the determination of the mechanic; driving force, Delta K-eff. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Lang, M (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 39 TC 2 Z9 2 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 0-8031-2486-4 J9 AM SOC TEST MATER PY 1999 VL 1332 BP 474 EP 495 DI 10.1520/STP14965S PG 22 WC Engineering, Mechanical; Mechanics; Metallurgy & Metallurgical Engineering SC Engineering; Mechanics; Metallurgy & Metallurgical Engineering GA BM73J UT WOS:000079623500026 ER PT J AU Phelps, JY Hickman, TN Levine, AS Zacur, HA Wallach, EA Hinton, EL AF Phelps, JY Hickman, TN Levine, AS Zacur, HA Wallach, EA Hinton, EL TI Predictive value of serum estradiol levels for IVF pregnancy outcome after gonadotropin stimulation? Reply of the authors SO FERTILITY AND STERILITY LA English DT Letter C1 Wilford Hall USAF Med Ctr, Dept Obstet & Gynecol, Div Reprod Endocrinol, Lackland AFB, TX 78236 USA. Tampa Obstet Fertil & Gynecol, Brandon, FL USA. RP Phelps, JY (reprint author), Wilford Hall USAF Med Ctr, Dept Obstet & Gynecol, Div Reprod Endocrinol, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0015-0282 J9 FERTIL STERIL JI Fertil. Steril. PD JAN PY 1999 VL 71 IS 1 BP 183 EP 184 PG 2 WC Obstetrics & Gynecology; Reproductive Biology SC Obstetrics & Gynecology; Reproductive Biology GA 157MD UT WOS:000078065500037 ER PT S AU Noah, DL Sobel, AL Ostroff, SM Kildew, JA AF Noah, DL Sobel, AL Ostroff, SM Kildew, JA BE Frazier, TW Richardson, DC TI Biological warfare training - Infectious disease outbreak differentiation criteria SO FOOD AND AGRICULTURAL SECURITY: GUARDING AGAINST NATURAL THREATS AND TERRORIST ATTACKS AFFECTING HEALTH, NATIONAL FOOD SUPPLIES, AND AGRICULTURAL ECONOMICS SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT International Conference on Food and Agricultural Security CY SEP 28-30, 1998 CL WASHINGTON, D.C. SP FEd Bur Investigat Lab, USDA ARS, Amer Vet Med Assoc, Dept Def Vet Serv Activ, Louisiana State Univ, FMI Sci Lab, Natl Consortium Genom Resources Management & Serv AB The threat of biological terrorism and warfare may increase as the availability of weaponizable agents increase, the relative production costs of these agents decrease, and, most importantly, there exist terrorist groups willing to use them. Therefore, an important consideration during the current emphasis of heightened surveillance for emerging infectious diseases is the capability to differentiate between natural and intentional outbreaks, Certain attributes of a disease outbreak, while perhaps not pathognomic for a biological attack when considered singly, may in combination with other attributes provide convincing evidence for intentional causation. These potentially differentiating criteria include proportion of combatants at risk, temporal patterns of illness onset, number of cases, clinical presentation, strain/variant, economic impact, geographic location, morbidity/mortality, antimicrobial resistance patterns, seasonal distribution, zoonotic potential, residual infectivity/toxicity, prevention/therapeutic potential, route of exposure, weather/climate conditions, incubation period, and concurrence with belligerent activities of potential adversaries. C1 USAF, Med Operat Agcy, SGPA, Bolling AFB, Washington, DC 20332 USA. Sandia Natl Labs, Syst Res Ctr, Albuquerque, NM 87185 USA. Ctr Dis Control & Prevent, Natl Ctr Infect Dis, Atlanta, GA 30333 USA. RP Noah, DL (reprint author), USAF, Armed Forces Med Intelligence Ctr, Ft Detrick, MD 21702 USA. NR 10 TC 4 Z9 4 U1 0 U2 1 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-230-4 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1999 VL 894 BP 37 EP 43 DI 10.1111/j.1749-6632.1999.tb08041.x PG 7 WC Agricultural Economics & Policy; Agronomy; Biotechnology & Applied Microbiology; Food Science & Technology SC Agriculture; Biotechnology & Applied Microbiology; Food Science & Technology GA BP47M UT WOS:000085238200006 PM 10681967 ER PT S AU Hickson, RD AF Hickson, RD BE Frazier, TW Richardson, DC TI Infecting soft targets - Biological weapons and Fabian forms of indirect grand strategy SO FOOD AND AGRICULTURAL SECURITY: GUARDING AGAINST NATURAL THREATS AND TERRORIST ATTACKS AFFECTING HEALTH, NATIONAL FOOD SUPPLIES, AND AGRICULTURAL ECONOMICS SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT International Conference on Food and Agricultural Security CY SEP 28-30, 1998 CL WASHINGTON, D.C. SP FEd Bur Investigat Lab, USDA ARS, Amer Vet Med Assoc, Dept Def Vet Serv Activ, Louisiana State Univ, FMI Sci Lab, Natl Consortium Genom Resources Management & Serv C1 USAF Acad, Dept Philosophy & Fine Arts, HQ USAFA DFEG Hickson, Colorado Springs, CO 80840 USA. RP Hickson, RD (reprint author), USAF Acad, Dept Philosophy & Fine Arts, HQ USAFA DFEG Hickson, 2354 Fairchild Dr,Suite 6K12, Colorado Springs, CO 80840 USA. NR 4 TC 1 Z9 1 U1 0 U2 2 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-230-4 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1999 VL 894 BP 108 EP 117 DI 10.1111/j.1749-6632.1999.tb08053.x PG 10 WC Agricultural Economics & Policy; Agronomy; Biotechnology & Applied Microbiology; Food Science & Technology SC Agriculture; Biotechnology & Applied Microbiology; Food Science & Technology GA BP47M UT WOS:000085238200018 PM 10681979 ER PT B AU Woodward, C Kajihara, SA Rao, SI Dimiduk, DM AF Woodward, C Kajihara, SA Rao, SI Dimiduk, DM BE KIM, YW Dimiduk, DM Loretto, MH TI The influence of solid solutions on flow behavior in gamma-TiAl SO GAMMA TITANIUM ALUMINIDES 1999 LA English DT Proceedings Paper CT 2nd International Symposium on Gamma Titanium Aluminides held in Conjunction with the TMS 1999 Annual Meeting CY MAR 01-04, 1999 CL SAN DIEGO, CA SP TMSSMD Titanium Comm, AFRL, GKSS, HOWMET, IRC, Kyoto Univ, GE ID TITANIUM ALUMINIDES; ELASTIC-CONSTANTS; CREEP-BEHAVIOR; POINT-DEFECTS; ALLOYS; STRESS; AL; SYSTEMS; ENERGY AB Modifications of alloy chemistry are often used to tailor the intrinsic flow behavior of structural materials. Models of solution strengthening, high temperature yield stress and creep must relate the effects of chemistry to the mechanisms that influence these material properties. In ordered alloys, additional information regarding the crystallographic site occupancy of ternary elements is required. In this study relaxed structures and energies for intrinsic and substitutional point defects are calculated using a first principles plane-wave-pseudopotential method. Calculated defect energies are used in a grand canonical formalism to predict the density and site preferences of solid-solutions (Si, Cr, Nb, Mo, Ta and W) in gamma-TiAl. The model also gives the density of thermal defects, in this case vacancies, as a function of alloy composition. In these materials, as in simple metals, the presence of vacancies strongly influences bulk diffusion rates. Limiting the density of constitutional and thermal vacancies by alloying may produce materials with enhanced creep properties. Also, size and modulus misfit parameters are calculated using the first principles method in order to understand solid-solution strengthening effects. The interaction of these defects with dissociated ordinary and <101] screw dislocations are evaluated within anisotropic elasticity theory. The derived interaction strength is then related to solid-solution strengthening for these defect centers. Predicted solid-solution effects are in good agreement with experimental observations for the binary alloy. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Woodward, C (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 43 TC 15 Z9 15 U1 4 U2 6 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-451-8 PY 1999 BP 49 EP 58 PG 10 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BP80P UT WOS:000086245200007 ER PT B AU Rao, S AF Rao, S BE KIM, YW Dimiduk, DM Loretto, MH TI Atomistic simulations of cross-slip processes in L1(0) TiAl SO GAMMA TITANIUM ALUMINIDES 1999 LA English DT Proceedings Paper CT 2nd International Symposium on Gamma Titanium Aluminides held in Conjunction with the TMS 1999 Annual Meeting CY MAR 01-04, 1999 CL SAN DIEGO, CA SP TMSSMD Titanium Comm, AFRL, GKSS, HOWMET, IRC, Kyoto Univ, GE ID EMBEDDED-ATOM METHOD; SINGLE-CRYSTALS; TEMPERATURE-DEPENDENCE; DISLOCATION MECHANISMS; 1/2<110> DISLOCATIONS; DEFORMATION-BEHAVIOR; SCREW DISLOCATIONS; FAULT ENERGIES; YIELD STRESS; ALLOYS AB The yield stress anomaly in gamma-TiAl at high temperatures, for certain orientations of the applied stress, is attributed to the formation of a high density of obstacles due to double cross-slip or kink-kink colisions (Viguier lock) on ordinary a/2<110] screw dislocations. In this manuscript, the structure, energetics and lateral mobility of cross-slip processes as well as elementary kink-kink colisions on a/2<110] screw dislocations in Ll(0) TiAl are simulated using lattice statics within the Embedded Atom Method (EAM) formalism. 2 and 3-D Green's function (GF) techniques are used to relax the boundary forces in the simulations. The cross-slip energy evaluated for gamma-TiAl from these simulations is consistent with the observed density of obstacles on a/2<110] screw dislocations at high temperatures in the yield anomaly regime. Energetically, in contrast to isotropic elasticity estimates, kink-kink colisions are found to be relatively unstable with an interaction energy of similar to -0.03eV. The lateral mobility of a Viguier lock is found to be somewhat curtailed due to the presence of non-planar core components at the center of the lock and is similar to 0.0015 mu. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, Wright Patterson AFB, OH 45433 USA. RP Rao, S (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, Wright Patterson AFB, OH 45433 USA. NR 50 TC 1 Z9 1 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-451-8 PY 1999 BP 97 EP 104 PG 8 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BP80P UT WOS:000086245200013 ER PT B AU Dimiduk, DM Vasudevan, VK AF Dimiduk, DM Vasudevan, VK BE KIM, YW Dimiduk, DM Loretto, MH TI Isothermal and continuous cooling decomposition of alpha and beta phases in gamma titanium aluminides SO GAMMA TITANIUM ALUMINIDES 1999 LA English DT Proceedings Paper CT 2nd International Symposium on Gamma Titanium Aluminides held in Conjunction with the TMS 1999 Annual Meeting CY MAR 01-04, 1999 CL SAN DIEGO, CA SP TMSSMD Titanium Comm, AFRL, GKSS, HOWMET, IRC, Kyoto Univ, GE ID TIAL-BASED ALLOYS; AL-ALLOY; TRANSFORMATION; MICROSTRUCTURE; EVOLUTION AB The last decade led to significant engineering advances and component demonstrations for gamma-alloy products. The variety of alloy chemistries and process variations available for these products results in a spectrum of microstructures and property variation for the alloys. However, the quantitative aspects of solid-state reactions and microstructural evolution kinetics, as well as the influences of alloy composition upon these, are relatively unstudied. This manuscript succinctly describes the isothermal and continuous-cooling transformations for gamma alloys across a range of compositions from binary, and ternary bases to complex multicomponent chemistries of commercial interest. Time-temperature-transformation curves are compared, and the effects of Al concentration and selected alloying additions are highlighted. Both beta-phase forming elements (Cr, Mo & W) and boron in the alloys are examined as grain-size controlling agents. When the alloy contains such agents, the transformation kinetics may be significantly altered relative to other gamma alloys, thus changing the thermal process path and affecting the perfection of lamellar microstructures. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL, Wright Patterson AFB, OH 45434 USA. RP USAF, Res Lab, Mat & Mfg Directorate, AFRL, MLLM Bldg 655,2230 10th St, Wright Patterson AFB, OH 45434 USA. NR 26 TC 20 Z9 20 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-451-8 PY 1999 BP 239 EP 246 PG 8 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BP80P UT WOS:000086245200030 ER PT B AU Larsen, JM Rosenberger, AH Worth, BD Li, KZ Maxwell, DC Porter, WJ AF Larsen, JM Rosenberger, AH Worth, BD Li, KZ Maxwell, DC Porter, WJ BE KIM, YW Dimiduk, DM Loretto, MH TI Assuring reliability of gamma titanium aluminides in long-term service SO GAMMA TITANIUM ALUMINIDES 1999 LA English DT Proceedings Paper CT 2nd International Symposium on Gamma Titanium Aluminides held in Conjunction with the TMS 1999 Annual Meeting CY MAR 01-04, 1999 CL SAN DIEGO, CA SP TMSSMD Titanium Comm, AFRL, GKSS, HOWMET, IRC, Kyoto Univ, GE ID FATIGUE-CRACK GROWTH; TEMPERATURE; FRACTURE; BEHAVIOR; ALLOY AB Gamma TiAl alloys offer the potential for major reductions in the weight of turbine engine components, if higher-density materials can be replaced without sacrificing long-term reliability in service. To assess this potential, an overview is presented of the structural capabilities available from gamma titanium aluminide alloys. Emphasis is given to effects of material defects, mechanistic aspects of fatigue damage evolution, and the roles of high temperature, time-dependent deformation and environment. Although gamma alloys exhibit excellent fatigue strengths, in many applications the material's resistance to service-induced damage is a critical concern. In turbine engines, such damage may result from impacts by foreign objects in the flow path. In addition, numerous components in turbine engines are subject to both low- and high-cycle fatigue. To predict the range of behavior that may be expected for gamma titanium aluminides requires consideration of damage tolerance, specifically addressing the potential for growth of small fatigue cracks that may form under a variety of circumstances. Approaches for life prediction in these materials are discussed, emphasizing the roles of fatigue crack initiation and growth. In addition, an attempt is made to assess the strengths and limitations of these materials with respect to application requirements and to suggest avenues for improvements in the balance of mechanical properties. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RP Larsen, JM (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. NR 24 TC 13 Z9 13 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-451-8 PY 1999 BP 463 EP 472 PG 10 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BP80P UT WOS:000086245200060 ER PT B AU Kim, YW Jata, KV AF Kim, YW Jata, KV BE KIM, YW Dimiduk, DM Loretto, MH TI Crack growth in a nearly fully-lamellar gamma TiAl alloy at 650 degrees C and 800 degrees C under sustained load SO GAMMA TITANIUM ALUMINIDES 1999 LA English DT Proceedings Paper CT 2nd International Symposium on Gamma Titanium Aluminides held in Conjunction with the TMS 1999 Annual Meeting CY MAR 01-04, 1999 CL SAN DIEGO, CA SP TMSSMD Titanium Comm, AFRL, GKSS, HOWMET, IRC, Kyoto Univ, GE ID FRACTURE; CREEP AB Crack growth behavior of a gamma titanium aluminide alloy, K5S, was investigated at 650 and 800 degrees C under constant loading conditions in a nearly fully-lamellar microstructural form. Cracking at both temperatures ensued at stress intensities (K) higher than respective fracture initiation toughness. At 650 degrees C, creep crack extension occurs through the formation of microcracks (interlamellar separation) and their joining to the main crack-tip through ligament fracture. This process featured a relatively rapid initial crack growth but at constantly decreasing rates, followed by a nearly no growth stage. At 800 degrees C, crack extension was accompanied by extensive plastic deformation and consisted of an initial rapid transition period and a subsequent steady state. For similar K's, crack extension and growth-rate were greater at 800 degrees C than at 650 degrees C, but even these were very slow processes. The cracking modes were: 1) ligament fracture leading to predominantly transgranular fracture at 650 degrees C and 2) predominantly boundary fracture at 800 degrees C consisting of intergranular fracture often involving formation and coalescence of voids, and interlamellar separation in the absence of ligaments. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Kim, YW (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-451-8 PY 1999 BP 509 EP 516 PG 8 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BP80P UT WOS:000086245200065 ER PT B AU John, R Rosenberger, AH DeLuca, D Porter, WJ Li, KZ AF John, R Rosenberger, AH DeLuca, D Porter, WJ Li, KZ BE KIM, YW Dimiduk, DM Loretto, MH TI Mixed mode crack growth in a gamma titanium aluminide alloy SO GAMMA TITANIUM ALUMINIDES 1999 LA English DT Proceedings Paper CT 2nd International Symposium on Gamma Titanium Aluminides held in Conjunction with the TMS 1999 Annual Meeting CY MAR 01-04, 1999 CL SAN DIEGO, CA SP TMSSMD Titanium Comm, AFRL, GKSS, HOWMET, IRC, Kyoto Univ, GE ID FRACTURE-BEHAVIOR; INTERMETALLIC ALLOYS; CRYSTALS; FATIGUE AB The results of an investigation of mixed mode (mode I and mode II) loading on the crack growth behavior of a gamma titanium aluminide (TiAl) alloy are discussed. A centrally notched disk specimen was used, and the tests were conducted at room temperature. Mixed mode loading conditions were achieved by orienting the machined flaw at different angles to the loading axis. A specimen with large (approximate to 5 mm) grains was used to characterize the interlamellar growth under mixed mode loading conditions. Preliminary results indicate that interlamellar mixed mode crack growth rate is approximate to 10-100X faster than the transgranular mode I long crack growth rate and up to approximate to 10X faster than small crack growth rate. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RP John, R (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-451-8 PY 1999 BP 535 EP 540 PG 6 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BP80P UT WOS:000086245200068 ER PT B AU Planck, SK Rosenberger, AH AF Planck, SK Rosenberger, AH BE KIM, YW Dimiduk, DM Loretto, MH TI The effects of prolonged high temperature air exposure on the monotonic and cyclic properties of a gamma titanium aluminide alloy SO GAMMA TITANIUM ALUMINIDES 1999 LA English DT Proceedings Paper CT 2nd International Symposium on Gamma Titanium Aluminides held in Conjunction with the TMS 1999 Annual Meeting CY MAR 01-04, 1999 CL SAN DIEGO, CA SP TMSSMD Titanium Comm, AFRL, GKSS, HOWMET, IRC, Kyoto Univ, GE ID INTERMETALLIC ALLOYS; PST CRYSTALS; DUCTILITY AB This study examines both the tensile ductility degradation and changes in the fatigue resistance after high temperature exposure in laboratory air. High temperature exposure is known to degrade the tensile ductility of gamma titanium aluminides however, the effect of such an exposure on the fatigue performance of this class of alloys is not clear. Tensile and fatigue tests at room temperature, 540 degrees C, and 760 degrees C were conducted following 50 and 500 hour air exposures at 760 degrees C to determine the degree of degradation of the monotonic and cyclic properties due to prolonged high temperature exposure of a gamma titanium aluminide. The embrittled layer that formed during exposure was characterized using microhardness and scanning electron microscopy. The fracture of the embrittled layer lends to a reduction in the room temperature ductility and strength. The removal of the affected surface layer by low-stress grinding restores the unexposed tensile properties. The high temperature exposure results in a modest degradation of the fatigue resistance of this gamma alloy at room temperature and 760 degrees C. However, at 540 degrees C, there is a more severe reduction in fatigue performance due to the exposure. The brittle surface layer aids crack initiation which, when combined with the poor fatigue crack growth resistance at this temperature, results in the largest overall reduction in fatigue performance. Again, removal of the affected surface layer restores the unexposed fatigue properties at all temperatures. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Planck, SK (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 21 TC 7 Z9 7 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-451-8 PY 1999 BP 791 EP 798 PG 8 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BP80P UT WOS:000086245200099 ER PT S AU Madden, TJ Hager, GD Lampson, AI Crowell, PG AF Madden, TJ Hager, GD Lampson, AI Crowell, PG BE Dorko, EA TI A comparison of subsonic and supersonic mixing mechanisms for the chemical oxygen-iodine laser (COIL) using computational fluid dynamic (CFD) simulations SO GAS AND CHEMICAL LASERS AND INTENSE BEAM APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Gas and Chemical Lasers and Intense Beam Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE ID ZONE STRUCTURE AB Simulation of chemical lasers such as the chemical oxygen-iodine laser (COIL) laser is of timely interest due to ongoing commercial and military development programs. Accurate models of the gas dynamics and chemistry within a COIL have been developed using Computational Fluid Dynamics (CFD) codes, matching data from experiments designed to probe these physics. This work details the use of these codes to investigate the supersonic injection of molecular I-2 and atomic I into the supersonic region of the O-2((1)Delta) flow in the COIL, and compare these results with a simulation of sonic injection of I-2 into the subsonic region of the O-2((1)Delta) flow. The performance of each of these injection mechanisms is characterized by the theoretical power extracted from a Fabry-Perot resonator model, which then serves as the primary basis for comparison. Additional quantities such as power available and chemical efficiency are used to compare and contrast the performance of each concept. Based on these comparisons, the supersonic-supersonic injection methods demonstrate a performance increase over the traditional subsonic methods, with supersonic injection of I atoms providing the greatest performance increase. C1 USAF, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Madden, TJ (reprint author), USAF, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 13 TC 2 Z9 2 U1 1 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 0-8194-3082-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3612 BP 135 EP 146 DI 10.1117/12.350649 PG 12 WC Optics SC Optics GA BN29G UT WOS:000081441900019 ER PT S AU Henshaw, TL Madden, TJ Herbelin, JM Manke, GC Anderson, BT Tate, RF Hager, GD AF Henshaw, TL Madden, TJ Herbelin, JM Manke, GC Anderson, BT Tate, RF Hager, GD BE Dorko, EA TI Measurement of gain on the 1.315 mu m transition of atomic iodine produced from the NCl(a(1)Delta)+I(P-2 (3/2)) energy transfer reaction SO GAS AND CHEMICAL LASERS AND INTENSE BEAM APPLICATIONS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Gas and Chemical Lasers and Intense Beam Applications II CY JAN 25-26, 1999 CL SAN JOSE, CA SP SPIE DE gain; population inversion; atomic iodine; NCl (a(1)Delta) metastables; azides; energy transfer ID CHEMICAL-LASER; RATE CONSTANTS AB A direct measurement of gain on the electronic I (P-2(3/2)) - I*(P-2(1/2)) transition of atomic iodine at 1.315 mu m using tunable diode laser is demonstrated The population inversion results from the efficient energy transfer between NCl (a(1)Delta) metastables and I (P-2(3/2)) atoms. Ground state iodine atoms and NCl (a(1)Delta) metastables are produced in a transverse subsonic flow device from the stepwise reaction of Cl atoms with HI followed by the reaction of Cl with azide (N-3) radicals, respectively. Under current experimental conditions, a gain of 0.020%/cm is obtained and appears to be limited by reagent number density. A kinetic model was constructed to simulate the experimental gain profile using a mechanism consisting of fully coupled finite rate chemistry and 1-D fluid dynamics. Good agreement with experimental and theoretical calculations are obtained. C1 USAF, DELC, Kirtland AFB, NM 87117 USA. RP Henshaw, TL (reprint author), USAF, DELC, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 26 TC 9 Z9 10 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 0-8194-3082-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3612 BP 147 EP 156 DI 10.1117/12.350650 PG 10 WC Optics SC Optics GA BN29G UT WOS:000081441900020 ER PT J AU Lee, MC Klien, EMC Burke, WJ Zhang, AX Riddolls, RJ Kuo, SP Sulzer, MP Isham, B AF Lee, MC Klien, EMC Burke, WJ Zhang, AX Riddolls, RJ Kuo, SP Sulzer, MP Isham, B TI Augmentation of natural ionospheric plasma turbulence by HF heater waves SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB HF heating offers a powerful technique for controlled studies of ionospheric plasma turbulence. Heater waves generate large plasma density depletions and sheet-like ionospheric irregularities in the F region, which can give rise to spread F backscatter. Electric fields associated with the induced irregularities can seed plasma instabilities, driven by such environmental causes as density gradients and ambient electric fields, to enhance spread F signatures. Significant reductions in the height-integrated radar backscatter power, measured during the HF heating, indicate the depletion of magnetic flux tubes. Density gradients at the edges of the depletions provide new sources of free energy to augment ionospheric plasma turbulence, enhancing the spread F processes. Furthermore, depleted magnetic flux tubes create and/or alter ionospheric ducts thus affecting radio wave propagation. C1 MIT, Plasma Sci & Fus Ctr NW16 240, Cambridge, MA 02139 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. Polytech Univ, Farmingdale, NY 11735 USA. Natl Astron & Ionosphere Ctr, Arecibo Observ, Arecibo, PR 00613 USA. RP Lee, MC (reprint author), MIT, Plasma Sci & Fus Ctr NW16 240, 167 Albany St, Cambridge, MA 02139 USA. NR 12 TC 13 Z9 13 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 1 PY 1999 VL 26 IS 1 BP 37 EP 40 DI 10.1029/1998GL900266 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 158MF UT WOS:000078118700010 ER PT S AU Slivinsky, S Galloway, R Breitling, S Wilborn, C Bukley, A AF Slivinsky, S Galloway, R Breitling, S Wilborn, C Bukley, A BE Culp, RD Weimer, DJ TI Missile Technology Demonstration 3 (MTD-3) flight performance SO GUIDANCE AND CONTROL 1999 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 22nd Annual AAS Rocky Mountain Guidance and Control Conference CY FEB 03-07, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Sci AB The Missile Technology Demonstration Program is a cooperative program between the Ballistic Missile Technology Office of the Air Force Research Laboratory, Kirtland AFB, New Mexico and the Theater Targets Product Office of the US Army Space and Missile Defense Command, Huntsville, Alabama. Through the launch of a series of ballistic missile experiments, technology demonstrations to validate the use of the Global Positioning Systems (GPS) for range safety and precision guidance, automated self-destruct algorithms, high speed penetrators and smart fuses have and will be executed. These demonstrations ultimately support developing the capability for global strike against weapons of mass destruction and hard and deeply buried targets using conventional means of deterrence. A sub-orbital missile night from the White Sands Missile Range (WSMR) was launched on 24 September 1998. Designated Missile Technology Demonstration-3 (MTD-3), it was the third flight of its kind having the principle objective of demonstrating GPS and Differential GPS (DGPS) technology applied to range safety and tracking and precision guidance. In addition to a tightly coupled Inertial Platform Assembly/DGPS navigation system, five GPS experiments were flown. Four of the experiments flew in the booster interstage module and one was a re-entry vehicle (RV) experiment. An additional experiment package in the MTD-3 RV comprised a 664-pound earth penetrator instrumented with two accelerator packages. The RV impacted the ground at approximately 4000 feet/second. The flight path angle at impact was near vertical. Excellent miss distance and navigation accuracy was achieved. The impact site was located within the boundaries of the alternate Seismic Hardrock In-situ Source Test site on the north end of WSMR, which is of weathered granite composition. This paper provides a brief background on the MTD-1 and MTD-2 flights and provides a more detailed discussion of the MTD-3 mission and flight results. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Slivinsky, S (reprint author), USAF, Res Lab, Space Vehicles Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 2 TC 0 Z9 0 U1 1 U2 1 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-456-7 J9 ADV ASTRONAUT SCI PY 1999 VL 101 BP 351 EP 364 PG 14 WC Engineering, Aerospace SC Engineering GA BN14B UT WOS:000080857900022 ER PT J AU Ornstein, DL Zacharski, LR AF Ornstein, DL Zacharski, LR TI The use of heparin for treating human malignancies SO HAEMOSTASIS LA English DT Article; Proceedings Paper CT 6th International Symposium on Thromboembolic Diseases CY JUN 04-05, 1999 CL LISBON, PORTUGAL DE human; cancer; heparin; metastasis ID LOW-MOLECULAR-WEIGHT; ENDOTHELIAL GROWTH-FACTOR; CASEIN KINASE-II; CELL LUNG-CANCER; UNFRACTIONATED HEPARIN; SULFATED POLYSACCHARIDES; PERIOPERATIVE HEPARIN; BIOLOGICAL-ACTIVITY; PLATELET FACTOR-4; DERMATAN SULFATE AB There is a substantial amount of data implicating coagulation mechanisms in the pathogenesis of malignancy. Studies in some experimental animal models have shown that the anticoagulant heparin limits tumour growth and metastasis and prolongs survival. Experience with the effects of heparin on human malignancy is limited primarily to settings in which it was given either to prevent or to treat thrombosis in patients who also had cancer. However, these studies have shown noteworthy apparent improvement in cancer outcome with heparin, especially with low-molecular-weight heparin. There are several possible mechanisms by which heparin could potentially alter the natural history of cancer progression because of its ability to modify the cellular and molecular environment of tumour cells. This experience provides the rationale for definitive clinical trials of heparin in patients with cancer and also for further experimentation to define the mechanisms of antineoplastic activity by this familiar class of drugs. Copyright (C) 1999 S. Karger AG, Basel. C1 Wilford Hall USAF Med Ctr, Hematol Oncol Flight, San Antonio, TX 78227 USA. Vet Adm Med Ctr, White River Jct, VT USA. RP Wilford Hall USAF Med Ctr, Hematol Oncol Flight, 59th Med Wing, San Antonio, TX 78227 USA. NR 116 TC 31 Z9 37 U1 0 U2 0 PU KARGER PI BASEL PA ALLSCHWILERSTRASSE 10, CH-4009 BASEL, SWITZERLAND SN 0301-0147 J9 HAEMOSTASIS JI Haemostasis PY 1999 VL 29 SU 1 BP 48 EP 60 PG 13 WC Hematology SC Hematology GA 272NC UT WOS:000084655900008 PM 10629404 ER PT S AU Marasco, PL Task, HL AF Marasco, PL Task, HL BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI The effect on vision of light scatter from HMD visors and aircraft windscreens SO HELMET- AND HEAD-MOUNTED DISPLAYS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet-Mounted and Head-Mounted Displays IV Conference CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE light scatter; haze; vision; contrast threshold; visor AB The amount of scattered light, or haze, typically increases as transparent materials age, wear, become dirty, or become scratched from cleaning. Light scattered from scratched aircraft transparencies, such as windscreens, head-up-display combiners, and helmet visors, can potentially reduce pilot visual performance and reduce target detection range. Presented in this paper are the results of an investigation of light scattered from transparencies exhibiting different levels of wear and surface damage. Two methods of measuring scattered light are compared. Visual performance under conditions of white light scatter relevant to the use of helmet-mounted displays in the cockpit is also examined. C1 USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. RP Marasco, PL (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. NR 12 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 0-8194-3163-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3689 BP 2 EP 10 DI 10.1117/12.352817 PG 9 WC Engineering, Aerospace; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BN52E UT WOS:000082111800001 ER PT S AU Franck, DL Kang, RN AF Franck, DL Kang, RN BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI The effects of lasers on helmet mounted displays SO HELMET- AND HEAD-MOUNTED DISPLAYS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet-Mounted and Head-Mounted Displays IV Conference CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE laser eye protection; Helmet Mounted Displays AB The use of Helmet-Mounted Displays (HMD) and lasers is becoming widespread throughout the world. The Air Force Research Laboratory (AFRL) Helmet-Mounted Sensory Technologies (HMST) program is currently studying the effects incorporating the various laser eye protection (LEP) technologies into HMD technologies. LEP technologies currently available are absorptive organic dyes or reflective filters such as holograms or dielectric stacks. Because of the overall reduction in light transmittance and selective spectral filtering characteristics of various LEP technologies, compatibility with HMD technologies and, ultimately, aircrew acceptance must be addressed. This paper will discuss some of the HMST requirements needed to perform adequate LEP and maintain HMD performance. This paper will also include a review of different approaches being studied to meet those requirements. C1 USAF, Res Lab, HECV, Helmet Mounted Sensory Technol, Wright Patterson AFB, OH 45433 USA. RP Franck, DL (reprint author), USAF, Res Lab, HECV, Helmet Mounted Sensory Technol, Wright Patterson AFB, OH 45433 USA. NR 2 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 0-8194-3163-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3689 BP 11 EP 18 DI 10.1117/12.352827 PG 8 WC Engineering, Aerospace; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BN52E UT WOS:000082111800002 ER PT S AU Task, HL Goodyear, C AF Task, HL Goodyear, C BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Effects of aircraft windscreens and canopies on HMT/D aiming accuracy: Part 3 SO HELMET- AND HEAD-MOUNTED DISPLAYS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet-Mounted and Head-Mounted Displays IV Conference CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE helmet-mounted displays; aircraft windscreens; aiming accuracy; aiming error; angular deviation; canopies; cueing systems AB Modem fighter aircraft windscreens and canopies are typically made of curved, transparent plastic for improved aero-dynamics and bird-strike protection. Since they are curved these transparencies often refract light in such a way that a pilot looking through the transparency will see a target in a location other than where it really is. This effect has been known for many years and methods to correct the aircraft head-up display (HUD) for these angular deviations have been developed and employed. The same problem occurs for helmet-mounted display/trackers (HMD/Ts) used for target acquisition. However, in this case, the pilot can look through any part of the transparency instead of being constrained to just the forward section as in the case of the HUD and his/her head position can be anywhere in a rather large motion box. To explore the magnitude of these aiming errors several F-15, F-16, F-18, and F-22 transparency systems were measured from a total of 12 different eye positions centered around the HMD Eye (the HMD Eye was defined to be a point 1.25 inches to the right of the aircraft Design Eye). The collection of eye points for assessing HMT/D aiming accuracy were: HMD Eye, 3 inches left and right of HMD Eye, 2 inches above HMD Eye, and 2 inches forward of HMD Eye plus all combinations of these. Results from these measurements along with recommendations regarding means of assessing "goodness" of correction algorithms are presented. C1 USAF, Res Lab, Human Effectiveness Directorate HECV, Wright Patterson AFB, OH 45433 USA. RP Task, HL (reprint author), USAF, Res Lab, Human Effectiveness Directorate HECV, 2255 H St, Wright Patterson AFB, OH 45433 USA. NR 5 TC 3 Z9 3 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 0-8194-3163-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3689 BP 19 EP 29 DI 10.1117/12.352838 PG 11 WC Engineering, Aerospace; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BN52E UT WOS:000082111800003 ER EF