FN Thomson Reuters Web of Science™ VR 1.0 PT S AU Whiteley, MR Welsh, BM AF Whiteley, MR Welsh, BM BE Gonglewshi, JD Vorontsov, MA TI Effect of finite outer scale on the temporal properties of atmospheric tilt aberrations SO ARTIFICIAL TURBULENCE FOR IMAGING AND WAVE PROPAGATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Artificial Turbulence for Imaging and Wave Propagation CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE turbulence; atmospheric optics; adaptive optics; tilt compensation AB The temporal properties of the tilt aberration induced in a plane wave upon propagation through the atmosphere depends upon the statistical characteristics of the optical turbulence encountered along the propagation path. While the Kolmogorov model with infinite outer scale is often employed to describe turbulence, experimental studies indicate that the effective outer scale of atmospheric turbulence, designated Lo, is on the order of 5 m to 100 m. Accounting for the effects of finite outer scale alters the correlative properties of phase aberrations of all orders. Using Taylor's frozen flow hypothesis, we extend the results of spatial correlation studies to model the temporal correlation of wave-front tilt when atmospheric winds are present. We show that the correlative properties of the wave-front tilt depends upon the quantity nu tau/D, where nu is the wind speed, tau is the time delay between tilt measurements, and D is the diameter of the aperture in which the tilt is measured. The outer scale affects the temporal correlation according to the ratio L-0/D. Our results demonstrate that the tilt correlation falls off more rapidly as the relative outer scale is decreased. Correspondingly, the tilt power becomes more concentrated at higher frequencies. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Whiteley, MR (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2887-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3432 BP 2 EP 13 DI 10.1117/12.327983 PG 12 WC Optics SC Optics GA BM07L UT WOS:000077548200001 ER PT S AU McMackin, L Pierson, RE Hugo, RJ Truman, CR AF McMackin, L Pierson, RE Hugo, RJ Truman, CR BE Gonglewshi, JD Vorontsov, MA TI Optical tomography system for laboratory turbulence measurements SO ARTIFICIAL TURBULENCE FOR IMAGING AND WAVE PROPAGATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Artificial Turbulence for Imaging and Wave Propagation CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE optical tomography; flow visualization; temperature measurement; round jet shear layer; turbulence coherent structure; Hartmann sensing AB We describe the design and operation of a high speed optical tomography system for measuring two-dimensional images of a dynamic phase object at a rate of 5 kHz. Data from a set of eight Hartmann wavefront sensors is back-projected to produce phase images showing the details of the inner structure of a heated air flow. Series of reconstructions at different downstream locations illustrate the development of flow structure and the effect of acoustic flow forcing. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP McMackin, L (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-2887-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3432 BP 28 EP 37 DI 10.1117/12.327985 PG 10 WC Optics SC Optics GA BM07L UT WOS:000077548200003 ER PT S AU Carreras, RA Marker, DK Wilkes, JM AF Carreras, RA Marker, DK Wilkes, JM BE Gonglewshi, JD Vorontsov, MA TI Tunable membrane mirrors used with real time holography SO ARTIFICIAL TURBULENCE FOR IMAGING AND WAVE PROPAGATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Artificial Turbulence for Imaging and Wave Propagation CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn AB Space-based inflatable technology is of current interest to NASA, DOD, and in particular to the Air Force Research Laboratory. Potentially large gains in lowering launch cost;, through reductions in structural mass and volume are driving this activity. Diverse groups are researching and developing this technology fbr radio and radar antennae, optical telescopes, and sola power and propulsion applications. Regardless of the use, one common requirement for successful application is the accuracy of the inflated surface figure. This paper gives a very cursory description of the research being performed at the Air Force Research Laboratory in the fields of membrane mirrors and real time holography. First, the article will show a shape modification method for the membrane mirror, achieved through enforced boundary displacements. The membrane mirror shape! modification, resulted in moving the inflated membrane shape towards a desired optical profile. Minimization of the optical figure error is further discussed. Next, the optical requirements levied from the membrane minor to an optically addressed spatial light modulator performing real time holographic correction are discussed. A proposed optical configuration in which a real time holographic optical element could be combined with the membrane minor to achieve near diffraction limited optical performance is discussed. C1 USAF, Res Lab, AFRL, DEBS, Kirtland AFB, NM 87117 USA. RP Carreras, RA (reprint author), USAF, Res Lab, AFRL, DEBS, Kirtland AFB, NM 87117 USA. NR 0 TC 7 Z9 7 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 0-8194-2887-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3432 BP 120 EP 128 DI 10.1117/12.327977 PG 9 WC Optics SC Optics GA BM07L UT WOS:000077548200013 ER PT S AU Andersen, G White, WR Knize, RJ AF Andersen, G White, WR Knize, RJ BE Gonglewshi, JD Vorontsov, MA TI Large holographically corrected space telescopes SO ARTIFICIAL TURBULENCE FOR IMAGING AND WAVE PROPAGATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Artificial Turbulence for Imaging and Wave Propagation CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE holography; telescopes; aberrations; next generation space telescope AB The next generation optical space telescopes with apertures >10m for imaging, lidar, communications and directed energy focussing will be unable to use conventional technologies which are impractical or too costly. Our solution is to construct a telescope from a lightweight, low-quality primary, which is holographically corrected for surface distortions, in situ. This scheme makes it possible to correct for apertures of virtually unlimited size, over a narrow bandwidth, at optical and UV wavelengths. In this talk we present the first holographically corrected telescope ever constructed for astronomical imaging. We present evidence that a distant beacon, combined with a static holographic recording may be the most inexpensive and simplest approach. The design of the telescope also makes it possible to incorporate an adaptive optics correction system for compensation of longer-term mirror deformation/sag and thermal distortions. C1 USAF Acad, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. RP Andersen, G (reprint author), USAF Acad, Laser & Opt Res Ctr, Suite 2A6,2354 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 0-8194-2887-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3432 BP 129 EP 136 DI 10.1117/12.327978 PG 8 WC Optics SC Optics GA BM07L UT WOS:000077548200014 ER PT S AU Gruneisen, MT Wick, DV Martinez, T Wilkes, JM AF Gruneisen, MT Wick, DV Martinez, T Wilkes, JM BE Gonglewshi, JD Vorontsov, MA TI Correction of large dynamic aberrations by real-time holography using electro-optical devices and nonlinear optical media SO ARTIFICIAL TURBULENCE FOR IMAGING AND WAVE PROPAGATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Artificial Turbulence for Imaging and Wave Propagation CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE aberration compensation; spatial light modulators; holographic recording materials; and adaptive optics AB "Real-time holography compensates for severely aberrated primary mirrors in large aperture telescope systems. A prototype optically addressed liquid-crystal spatial light modulator device developed for this application is demonstrated with short response times, similar to 600 mu sec, and high diffraction efficiencies approaching 40%." C1 USAF, Res Lab, AFRL, DEBS, Kirtland AFB, NM 87117 USA. RP Gruneisen, MT (reprint author), USAF, Res Lab, AFRL, DEBS, Kirtland AFB, NM 87117 USA. NR 0 TC 7 Z9 7 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 0-8194-2887-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3432 BP 137 EP 150 DI 10.1117/12.327979 PG 14 WC Optics SC Optics GA BM07L UT WOS:000077548200015 ER PT B AU Hurwitz, JB AF Hurwitz, JB BE Hoadley, ED Benbasat, I TI Modeling time-pressured risky decision-making SO ASSOCIATION FOR INFORMATION SYSTEMS PROCEEDINGS OF THE AMERICAS CONFERENCE ON INFORMATION SYSTEMS LA English DT Proceedings Paper CT 4th AIS Americas Conference on Information Systems CY AUG 14-16, 1998 CL BALTIMORE, MD SP Assoc Informat Syst AB This paper describes a model, called Decision-Making under Risk In a Vehicular Environment (DRIVE), that simulates the trade-off between two strategies for achieving a goal in real time: 1) Responding quickly to meet a deadline and 2) delaying responses to better evaluate risks. DRIVE is used to predict the performance of art automobile driver waiting to cross an intersection as a car approaches from the cross street. In this task, the driver is punished for crashing into the oncoming car, but is also put under pressure to cross quickly. Results show a relationship between risk-taking on the intersection-crossing task and external measures of risk taking, including driving history and participation in risky activities. DRIVE model fits indicate that individual differences on this task can be accounted for by varying the decision-making parameters in the model, rather than the perceptual parameters. C1 USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. RP Hurwitz, JB (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ASSOCIATION INFORMATION SYSTEMS PI ATLANTA PA P.O. BOX 2712, ATLANTA, GA 30301-2712 USA PY 1998 BP 249 EP 251 PG 3 WC Business; Business, Finance; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Business & Economics; Computer Science GA BM34K UT WOS:000078432000086 ER PT S AU George, ER AF George, ER BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Optimization of satellite constellations for discontinuous global coverage via genetic algorithms SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB For many satellite applications continuous coverage of the Earth is not required. Substantial saving in the altitudes of the vehicles or number of vehicles required can be realized if intermittent coverage is allowable. However, the coverage characteristics and design of these constellations is not well understood. This paper presents a genetic algorithm as a robust method for obtaining optimal discontinuous coverage constellations. These constellations are generally unsymmetric and can sometimes offer twice the performance of Walker constellations. This paper presents an overview of the method and examines maximum revisit time results and coverage characteristics for 4, 5, and 6 satellite constellations. C1 USAF, Space & Missile Ctr, Los Angeles AFB, CA 90009 USA. RP George, ER (reprint author), USAF, Space & Missile Ctr, Los Angeles AFB, CA 90009 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 333 EP 346 PN 1-2 PG 14 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800021 ER PT S AU Shah, NH Proulx, RJ Kantsiper, B Cefola, PJ Draim, J AF Shah, NH Proulx, RJ Kantsiper, B Cefola, PJ Draim, J BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Automated station-keeping for satellite constellations SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The on-orbit control of future satellite constellations poses a great challenge. New approaches are required which result in viable control systems that are flexible reliable, and efficient, This work develops new methods for the maintenance of satellite constellations. Strategies which employ these methods are applied to analyze the control and coverage characteristics of the Ellipso(TM) constellation, The Automated Station-Keeping Simulator (ASKS), a software package developed for this project, is employed. C1 USAF, Washington, DC 20330 USA. RP Shah, NH (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 357 EP 385 PN 1-2 PG 29 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800023 ER PT S AU Spencer, DB Luus, KK AF Spencer, DB Luus, KK BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Overview of the Second European Conference on Space Debris SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB This paper provides a synopsis of the purpose, the contents, and the broad conclusions from the Second European Conference on Space Debris, which was held on 17-19 March 1997 in Darmstadt, Germany. A complete list of the papers and authors presented at this conference is given in the appendix. It is hoped that this type of survey paper will further disseminate results of international research in topics that are of interest to the general astrodynamics community. C1 USAF, Phillips Lab, NTS, Kirtland AFB, NM 87117 USA. RP Spencer, DB (reprint author), USAF, Phillips Lab, NTS, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 585 EP 599 PN 1-2 PG 15 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800037 ER PT S AU Hall, CD Ross, IM AF Hall, CD Ross, IM BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Dynamics and control problems in the deflection of Near-Earth Objects SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB In this report, we investigate the problem of mitigating the threat from an earth-impacting object. We provide a brief historical perspective of the subject, then focus on the problem of deflecting an object, with a unique new viewpoint leading to the development of a fundamental definition of the problem. Within the context of this fundamental deflection problem, we define several typical scenarios, each of which leads to classes of potential optimization problems to be solved. Many deflection strategies have been proposed in the literature, and we describe several of these, with emphasis on a classification that complements our fundamental definition. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Hall, CD (reprint author), USAF, Inst Technol, AFIT ENY Bldg 640,2950 P St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 613 EP 631 PN 1-2 PG 19 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800039 ER PT S AU Burns, RD AF Burns, RD BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Overview of the Twelfth International Symposium on Space Flight Dynamics SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The purpose of this paper is to provide an overview of the International Space Flight Dynamics Symposium, which was held 2-6, June 1997, in order to further distribute the information and results presented there. The symposium featured approximately seventy-nine papers in eight categories: Geostationary Satellites, Precision Orbit Determination; Orbit Determination; Attitude Determination and Control; Interplanetary Flight; Mathematics, Analysis, and Orbit Control; Systems and Operations; and Spacecraft Dynamics. C1 USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RP Burns, RD (reprint author), USAF, Phillips Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 647 EP 654 PN 1-2 PG 8 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800041 ER PT S AU Fischer, JD Cefola, PJ Proulx, RJ AF Fischer, JD Cefola, PJ Proulx, RJ BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI The evolution of highly-eccentric orbits: Decay phase analysis SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Highly eccentric orbits pose a unique challenge to orbit determination processes based on semi-analytic satellite theories. These orbits may be perturbed by a broad spectrum of the natural forces that govern the motion of a space object and are difficult to model over long arcs. This work identifies the perturbation model improvements in the Draper R&D version of the Goddard Trajectory Determination System (GTDS) necessary to improve accuracy for a difficult orbit type known as the Molniya class orbit. Molniya orbits, with an eccentricity of approximately 0.7, exaggerate the effects of eccentricity truncation in the J(2)(2) and tesseral resonance models. Additionally, these orbits may produce a steep reentry path and magnify the effects of atmospheric drag, particularly when the decay occurs near the minimum in the approximate 11 year solar cycle. This work analyzes the last portion of the evolution of these orbits, from the mission or operational phase to the final degradation of the orbit, The unique Draper Semianalytic Satellite Theory (DSST) and a Cowell numerical propagator are used for the long are orbit determination processing and parameter estimation during this decay phase. The MSISE-90 atmospheric model is integrated into GTDS to more accurately model the decay phase and a transition between the phases is investigated. By establishing the transition between the two orbital phases, improving the atmospheric model, analyzing the effects of drag short periodics, higher order drag terms, and drag-oblateness coupling, and identifying the remaining improvements necessary to accurately model this class of orbits, this work serves as the first step in an effort to accurately model the evolution of highly eccentric orbits. C1 USAF, Washington, DC 20330 USA. RP Fischer, JD (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1037 EP 1056 PN 1-2 PG 20 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800065 ER PT S AU McConnell, J Greenberg, R Brooks, RA Hsieh, J Grimes, F AF McConnell, J Greenberg, R Brooks, RA Hsieh, J Grimes, F BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Evaluation of GPS/IMU trajectory estimation performance for realtime missile flight safety SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The application of maturing technologies such as GPS and strapdown inertial navigation to the problems of flight safety for Ballistic missiles and Spacelift vehicles is of growing interest at the Eastern and Western Ranges, which are operated by the USAF Space Command. An area of particular interest is the integration of Global Positioning System (GPS) user equipment and on-board inertial measurement units (IMU) to exploit the synergism between these two technologies and achieve enhanced metric accuracy for realtime tracking and instantaneous impact prediction (IIP). The study reported herein examines a GPS/IMU integration mechanization which typifies that which would be expected in practice for realtime Ballistic missile and Spacelift vehicle applications. The performance of this mechanization is evaluated for the major classes of vehicles launched from the two Ranges, The results of this performance evaluation show clearly for all classes of vehicles and trajectories that the integrated mechanization provides superior accuracy to either a stand-alone GPS or IMU, A result of some significance is that an IMU of moderate accuracy augmented with only a relatively small quantity of GPS data ( early in flight and, in certain cases, in late midcourse flight) can satisfy all realtime flight safety metric accuracy requirements. RP McConnell, J (reprint author), 30 Space Wing XPE, Vandenberg AFB, CA 93437 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1119 EP 1134 PN 1-2 PG 16 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800070 ER PT S AU Slivinsky, SH Fountain, L Galloway, R Scott, AM AF Slivinsky, SH Fountain, L Galloway, R Scott, AM BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Missile Technology Demonstration flight test - 2 SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Ballistic Missile Technology Office at Phillips Laboratory, Kirtland AFB, NM, in cooperation with the Theatre Targets Product Office of the U.S. Army Space and Strategic Defense Command (USASSDC), launched a missile at White Sands Missile Range, New Mexico on January 29, 1997. The flight used Phillips-developed technologies and the Global Positioning System (GPS) to evaluate technologies that may reduce U.S. dependence on costly range instrumentation while improving safety systems. C1 USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RP Slivinsky, SH (reprint author), USAF, Phillips Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1135 EP 1144 PN 1-2 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800071 ER PT S AU Beck, JA Hall, CD AF Beck, JA Hall, CD BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Relative equilibria of a rigid satellite in a circular Keplerian orbit SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB We examine relative equilibria of a rigid body free to rotate about its center of mass which is constrained to follow a Keplerian orbit in a central gravitational field. We derive a noncanonical Hamiltonian formulation of this system and show how it relates to the noncanonical system for an unconstrained rigid body (due to Wang et al.) in a hierarchy of approximations of the two-body problem, For a particular approximation of the potential, the Keplerian system is equivalent to the classical approximation typically seen in the literature, We determine relative equilibria for this approximation and derive stability conditions for both arbitrary and axisymmetric bodies. C1 USAF, Phillips Lab PL VTS, Space Technol Directorate, Kirtland AFB, NM 87117 USA. RP Beck, JA (reprint author), USAF, Phillips Lab PL VTS, Space Technol Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1187 EP 1216 PN 1-2 PG 30 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800075 ER PT S AU Karasopoulos, HA Richardson, DL AF Karasopoulos, HA Richardson, DL BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Satellite nonlinear attitude motion about an oblate central body SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The nonlinear dynamics of the planar pitch attitude motion of a gravity-gradient satellite is numerically investigated for an elliptical polar orbit about an oblate, axially-symmetric, central body. Perturbations to the attitude and orbit equations due to the oblateness of the central body are shown to significantly affect satellite pitching motion. Eccentricity, assumed constant in most previous nonlinear analyses of planar pitch dynamics, varies as much as 15% for an example low altitude, Earth orbiting satellite. The resultant pitching motion is either periodic, quasiperiodic, or chaotic, depending upon the value of a satellite inertia ratio and the initial values for pitch angle, pitch angle rate, and the orbital elements. With this more elaborate model, chaos is detected in regions of the phase space where previous dynamical models depict only regular motion. C1 USAF, Wright Lab WL FIMA, Aeromech Div, Wright Patterson AFB, OH 45433 USA. RP Karasopoulos, HA (reprint author), USAF, Wright Lab WL FIMA, Aeromech Div, Bldg 450,2645 5th St,Suite 7, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1217 EP 1235 PN 1-2 PG 19 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800076 ER PT S AU Chastain, SH Chao, CC AF Chastain, SH Chao, CC BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI An evaluation of the Jacchia 1971 and MSISE 1990 atmospheric models using NASA ODERACS2 data SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB On 3 February 1995, the Space Shuttle Discovery (OV-103) on mission STS-63 deployed six Orbital Debris Radar Calibration Sphere (ODERACS2) objects, three spheres and three dipoles (similar to dumbbells). The orbits of these objects decayed into the atmosphere between 28 August 1995 and 9 March 1996 for the spheres and between 20 February 1995 and 2 March 1995 for the dipoles. The continuous measurements of the orbital elements and the physical dimensions of each object provide a good opportunity to evaluate atmospheric density models. Orbit analysts usually adjust the value of the atmospheric drag coefficient, C-d, to force the computed orbit decay to agree with the tracking data. The purpose is to compensate for errors in the density that are used in computing the orbital decay. Using the theoretical or physical drag coefficients, the atmospheric models are evaluated based on observations of C-d from tracking data. This paper is a follow-on to the previous study, "An Evaluation of Jacchia 1971 and MSIS 1990 Atmospheric Models with NASA ODERACS Decay Data". The NORAD 2-line element sets for the two ODERACS2 objects were processed by a semi-analytical, PC-based program, LIFETIME, LIFETIME differentially adjusts the ballistic coefficient used with the two atmosphere models so the computed orbit agrees closely with the observed orbit. Also, daily measurements of the solar flux index, F-10.7, and the earth's geomagnetic index, A(p), were collected and used in the LIFETIME simulation runs. From these, two sets of the drag coefficient, C-d, were computed from the ballistic coefficients, one set for each atmospheric model. Different altitude levels, from 350 Km to 150 Km, were used to show the variation of C-d in each model. The differences between the expected values of the density models and the values derived from the NASA data are calculated by dividing the average drag coefficient of an altitude level by the drag coefficient obtained from the orbital fit, The findings of this follow-on study may be useful to mission analysts for improving the accuracy of orbit decay prediction as well as fuel estimation for orbit sustenance for altitudes below 350 Km. C1 USAF, SMC, AXES, Los Angeles AFB, CA 90245 USA. RP Chastain, SH (reprint author), USAF, SMC, AXES, 160 Skynet St,Suite 2315, Los Angeles AFB, CA 90245 USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1311 EP 1329 PN 1-2 PG 19 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800081 ER PT S AU Vallado, DA Carter, SS AF Vallado, DA Carter, SS BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Accurate orbit determination from short-arc dense observational data SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Requirements have existed for several decades for highly-accurate satellite orbits. With increased computer power, simplified analytical techniques have lost most of their competitive edge and numerical techniques are experiencing widespread popularity. When coupled with increased accuracy requirements from commercial satellites owners and accurate computations for debris and close approach for the International Space Station, a reliable method must be found to form highly-accurate satellite state vectors. This paper explores one approach using dense observational data from short-arcs of geographically distributed sensor sites. In particular, dense observations (consisting of one observation per second for about two minutes) are analyzed to determine the accuracy that can be achieved via high fidelity, numerical, orbit-determination techniques. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Vallado, DA (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1587 EP 1601 PN 1-2 PG 15 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800099 ER PT S AU Wallace, S Sabol, C Carter, S AF Wallace, S Sabol, C Carter, S BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Use of the Raven optical sensor for deep space orbit determination SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Raven is an inexpensive, portable optical sensor that provides highly accurate observations on deep space objects. This paper discusses the details of the Raven telescope including its operation, the potential accuracy of the angular measurements produced by the Raven system, the impact of these observations on the accuracy of the orbit determination process, and an analysis of the observations that have been collected by Raven sites both at Maul and Albuquerque. Simulated data is used to evaluate the potential of Raven data to produce deep space orbits. External reference orbits on GPS satellites (available on the world aide web from the International GPS Service for Geodynamics (IGS)) and GEO satellites (TDRS-5 & GOES-10, available from NASA) are used as truth orbits to calibrate the Raven system. C1 USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RP Wallace, S (reprint author), USAF, Phillips Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1603 EP 1624 PN 1-2 PG 22 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800100 ER PT S AU Ford, KA Hall, CD AF Ford, KA Hall, CD BE Hoots, FR Kaufman, B Cefola, PJ Spencer, DB TI Flexible spacecraft reorientations using gimbaled momentum wheels SO ASTRODYNAMICS 1997 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Conference CY AUG 04-07, 1997 CL SUN VALLEY, ID SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB We study the reorientations of flexible spacecraft using momentum exchange devices. A new concise form of the equations of motion for a spacecraft with gimbaled momentum wheels and flexible appendages is presented. The derivation results in a set of vector nonlinear first order differential equations with gimbal torques and spin axis torques as the control inputs. Feedback control laws which result in smooth reorientations are sought with the goal of minimizing structural excitations. We pay special attention to a class of maneuvers wherein the magnitude of the momentum in the wheel cluster is held constant resulting in a so-called "stationary platform maneuver." The advantage of this maneuver is that the platform angular velocity remains small throughout, thereby reducing the excitation of the appendages. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Ford, KA (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-441-9 J9 ADV ASTRONAUT SCI PY 1998 VL 97 BP 1895 EP 1913 PN 1-2 PG 19 WC Engineering, Aerospace; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Meteorology & Atmospheric Sciences; Remote Sensing GA BK64Z UT WOS:000072955800116 ER PT S AU Friedman, JF Loos, G Baker, J Finkner, L Sanchez, D Percheron, I Restaino, S AF Friedman, JF Loos, G Baker, J Finkner, L Sanchez, D Percheron, I Restaino, S BE Reasenberg, RD TI The New University of Puerto Rico Air Force Research Laboratory initiative in adaptive optics interferometry. SO ASTRONOMICAL INTERFEROMETRY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Astronomical Interferometry CY MAR 20-24, 1998 CL KONA, HI SP SPIE, European So Observ DE adaptive optics; interferometer; Liquid Crystal wavefront compensation AB The University of Puerto Rico, Mayaguez, in conjunction with the Deep Space Surveillance Branch (DEBS) of the USAF Research Laboratory (AFRL) Phillips Site (PL) in Albuquerque, NM is initialing an Adaptive Optics (AO) Interferometry program. The program will begin with four projects. We currently have funding for a three element optical interferometer, described in this paper, using Technology developed at DEBS, for a new wavefront sensor and a Liquid Crystal (LC) wavefront compensator being presented at this meeting'(1-9) .and a Low Light Level Fringe Tracker (LLLFT)(1,6-11,16-24) Michelson: Interferometer. We are also developing a program to put a similarly configured inexpensive two-element interferometer test-bed in orbit. The interferometer would have optical elements on a 10-meter boom It will use Aperture Synthesis by rotation and motion of the elements along the booms. The third project under development would incorporate the initial 3-element interferometer into a larger array with the additional collaboration of New Mexico Tech and New Mexico State University at a 10,600' site near Socorro, NM. As part of the ground based interferometry effort we are trying to develop inexpensive meter class telescopes. The 0.75meter telescopes we are building for our small interferometer will serve as prototypes and system test-beds. The telescopes will be robotic, remotely operable, essentially self-orienting and portable. We hope to produce such systems for commercial distribution for approximately $250K each. All of the ground-based interferometric systems will be configured for remote operation and independent use of sub-arrays while upgrades and repairs are underway. The major thrust of the UPR effort will be to develop inexpensive interferometers for diverse applications with the law light level capabilities and the LC adaptive optics developed at the Phillips Site. Particular applications will be for high-resolution astronomy and satellite imaging. The adaptive optics will be such that they can be placed on the individual telescopes and are nor part of the interferometer. They will then serve as templates for AO systems of general interest. As an additional part of all of these projects we will try to develop the use of optical fibers for several applications. We would like to couple the telescopes with fiber if we can develop an efficient way to couple the output signal from the telescope to the fibers, In addition we hope to use fiber stretchers for optical path compensation to replace expensive conventional optical delay lines. C1 USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 USA. RP Friedman, JF (reprint author), USAF, Res Lab, DEBS, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 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 0-8194-2797-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3350 BP 330 EP 341 DI 10.1117/12.317095 PN 1-2 PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Optics SC Engineering; Astronomy & Astrophysics; Optics GA BL55C UT WOS:000075850300035 ER PT S AU Restaino, SR McBroom, RJ Baker, JT AF Restaino, SR McBroom, RJ Baker, JT BE Reasenberg, RD TI Single core and multi-core single mode optical fibers for optical interferometry SO ASTRONOMICAL INTERFEROMETRY, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Astronomical Interferometry CY MAR 20-24, 1998 CL KONA, HI SP SPIE, European So Observ DE single mode fibers; optical interferometry; beam recombination AB In this paper we present a status report of our single mode (SM) fiber work for interferometry. Ln the past two years two experiments have been carried out by our group at the Maul Space Surveillance Site linking two 1.2 meter telescopes using single mode fibers and obtaining white light fringes on alpha Bootis. During this experiment we were able to measure coupling efficiency between atmospherically degraded images, D/r(0)similar to 10, and the fibers using a tip/tilt mirrors on each of the two telescopes. We compared our results with theoretical calculations. Furthermore we will present some of the experimental results and 'lesson learned'. We will also present the progress on our multi-core single mode fibers program. We have a first four core prototype under test and preliminary results will be presented. C1 USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 USA. RP Restaino, SR (reprint author), USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 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 0-8194-2797-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3350 BP 1031 EP 1036 DI 10.1117/12.317170 PN 1-2 PG 6 WC Engineering, Aerospace; Astronomy & Astrophysics; Optics SC Engineering; Astronomy & Astrophysics; Optics GA BL55C UT WOS:000075850300113 ER PT S AU Restaino, SR Payne, DM AF Restaino, SR Payne, DM BE Devir, AD Kohnle, A Schreiber, U Werner, C TI Adaptive optics on a shoe string .... SO ATMOSPHERIC PROPAGATION, ADAPTIVE SYSTEMS, AND LIDAR TECHNIQUES FOR REMOTE SENSING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Atmospheric Propagation, Adaptive Systems, and Lidar Techniques for Remote Sensing II CY SEP 23-24, 1998 CL BARCELONA, SPAIN SP CNR, NASA, European Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev, Soc Photo Opt Instrumentat Engineers DE pupil masking; liquid crystals; fiber optics ID PHASE AB There are two main ways to mitigate the effects of atmospheric turbulence on an imaging system. A post facto approach, where data are opportunely acquired and processed in order to increase the overall resolution attainable by the optical system, speckle imaging is an example of such technique. The other approach is to use an adaptive optics system that will compensate for atmospheric effects before the data are recorded. Of course, the situation is not sharply distinct. Hybrid approaches have been proposed and demonstrated. Other approaches that an:a mid-way between the tyro are also possible. The basic idea of static and dynamic pupil masking will be presented. Experimental results based on point sources and extended objects will be presented. Advantages and limitation of such technique will be discussed. Finally some new ideas involving fiber optics and liquid crystals will be presented. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Restaino, SR (reprint author), USAF, Res Lab, 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 0-8194-2953-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3494 BP 152 EP 160 DI 10.1117/12.332413 PG 9 WC Engineering, Aerospace; Meteorology & Atmospheric Sciences; Remote Sensing; Optics SC Engineering; Meteorology & Atmospheric Sciences; Remote Sensing; Optics GA BM38U UT WOS:000078582100017 ER PT S AU Christou, JC Hege, EK Jefferies, S Cheselka, M AF Christou, JC Hege, EK Jefferies, S Cheselka, M BE Devir, AD Kohnle, A Schreiber, U Werner, C TI Physically constrained iterative deconvolution of Adaptive Optics images SO ATMOSPHERIC PROPAGATION, ADAPTIVE SYSTEMS, AND LIDAR TECHNIQUES FOR REMOTE SENSING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Atmospheric Propagation, Adaptive Systems, and Lidar Techniques for Remote Sensing II CY SEP 23-24, 1998 CL BARCELONA, SPAIN SP CNR, NASA, European Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev, Soc Photo Opt Instrumentat Engineers DE Adaptive Optics; astronomy; image post processing; deconvolution; blind deconvolution ID BLIND DECONVOLUTION AB Adaptive Optics produces diffraction-limited images but does not fully compensate for the atmospheric degradation of the incoming signal. Post processing is important to fully restore the image. The results of applying a physically constrained iterative deconvolution algorithm to Adaptive Optics data are presented here for different types of simulated data with different signal-to-noise ratios. 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 0-8194-2953-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3494 BP 175 EP 186 DI 10.1117/12.332416 PG 12 WC Engineering, Aerospace; Meteorology & Atmospheric Sciences; Remote Sensing; Optics SC Engineering; Meteorology & Atmospheric Sciences; Remote Sensing; Optics GA BM38U UT WOS:000078582100020 ER PT J AU Johnson, RE Allen, JR Schultz, T Liening, DA Bell, AF AF Johnson, RE Allen, JR Schultz, T Liening, DA Bell, AF TI The effects of linear acceleration on distortion product otoacoustic emissions in human ears SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID NORMALLY HEARING SUBJECTS AB Background: The effect of high levels of linear acceleration (G) on the cochlea has never been studied prospectively. Hypothesis: Linear acceleration at high levels has no effect on the human cochlea as demonstrated by a comparison of pre-and post-exposure measurements. Methods: There were 22 healthy volunteers who underwent exposure to up to 9 G in a military aviation training centrifuge. Prior to exposure they were screened for cochleovestibular disorders and underwent tympanometry, audiometry and distortion product otoacoustic emissions testing (DPOAE). Immediately after exposure, they underwent serial testing of each of these parameters until they returned to baseline. Results: There was no significant change in tympanometry in any subject. Audiometry revealed a temporary threshold shift of 30 db al 6 kHz in one ear of a single subject. This was accompanied by a complete loss of DPOAE at the same frequency. DPOAE did not return to baseline at 2 weeks even though the audiogram had reverted to baseline by 8 d. Four other ears displayed significant losses of emissions at single frequencies without an accompanying change on the audiogram. Conclusions: This study demonstrates that accelerative stress may cause transient injury to the cochlea. The mechanism of injury due to acceleration is probably ischemia, although a purely mechanical effect on the outer hair cells cannot be precluded. These data also reinforce a growing body of evidence that demonstrates the greater sensitivity of DPOAE over psychoacoustic resting in detecting early or subclinical cochlear damage. C1 Tripler Army Med Ctr, MCHK, DSH, Otolaryngol Head & Neck Surg Serv, Honolulu, HI 96859 USA. Armstrong Lab, Brooks AFB, TX 78235 USA. Walter Reed Army Med Ctr, Otolaryngol Head & Neck Surg Serv, Washington, DC 20307 USA. RP Johnson, RE (reprint author), Tripler Army Med Ctr, MCHK, DSH, Otolaryngol Head & Neck Surg Serv, Honolulu, HI 96859 USA. NR 28 TC 4 Z9 4 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 JAN PY 1998 VL 69 IS 1 BP 40 EP 44 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA YQ550 UT WOS:000071399000007 PM 9451532 ER PT B AU Simpson, JC Wood, MA Burke, CJ AF Simpson, JC Wood, MA Burke, CJ BE Meistas, EG Moskalik, P TI The effects of inclination angle on superhump pseudo-lightcurves SO BALTIC ASTRONOMY, VOL 7, NOS 1 AND 2 LA English DT Proceedings Paper CT 4th Whole Earth Telescope Workshop CY JUL 21-25, 1997 CL KONINKI, POLAND SP Cracow Pedagog Univ, UNESCO, KBN, Polish Acad Sci, Astron Comm DE stars, binaries, close; cataclysmic variables; accretion disks; hydrodynamics AB We present preliminary results from a three-dimensional smoothed particle hydrodynamics (SPH) simulation of an accretion disk in a low mass-ratio cataclysmic variable system representative of the SU UMa and AM CVn subclasses of dwarf novae. Using a simple ray-tracing scheme to identify "surface" particles as a function of viewing angle, we use the relative temperature distribution of these particles to estimate the particles' luminosities at a given timestep by convolving blackbody energy distributions with UBVRI filter response functions. These values are then corrected for limb-darkening and summed to produce pseudo-lightcurves and Fourier amplitude spectra which may be directly compared with observations. We find that the resulting amplitude spectra for inclination angles i less than or similar to 45 degrees are dominated by the superhump frequency, but that linear combination frequencies of the superhump and orbital periods begin to dominate the amplitude spectrum for systems with higher inclination angles. These preliminary calculations suggest that the observed harmonic structure of superhump light curves may provide independent constraints on SU UMa and AM CVn system inclinations. C1 Comp Sci Raytheon, Patrick AFB, FL 32925 USA. RP Simpson, JC (reprint author), Comp Sci Raytheon, CSR 1310,POB 4127, Patrick AFB, FL 32925 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INSTITUTE THEORETICAL PHYSICS & ASTRONOMY PI VILNIUS PA GOSTAUTO 12, VILNIUS 2600, LITHUANIA PY 1998 BP 255 EP 267 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL26X UT WOS:000074945200023 ER PT J AU Frei, MR Berger, RE Dusch, SJ Guel, V Jauchem, JR Merritt, JH Stedham, MA AF Frei, MR Berger, RE Dusch, SJ Guel, V Jauchem, JR Merritt, JH Stedham, MA TI Chronic exposure of cancer-prone mice to low-level 2450 MHz radiofrequency radiation SO BIOELECTROMAGNETICS LA English DT Article DE microwaves; long-term exposure; mammary tumors; tumor incidence ID MICROWAVE-RADIATION; MAMMARY-TUMORS; LIFE-SPAN; RATS; BODY; PROLIFERATION; ABSORPTION; RESPONSES; INVITRO; FIELDS AB The purpose of this study was to determine whether chronic, low-level exposure of mammary-tumor-prone mice to 2450 MHz radiofrequency radiation (RFR) promotes an earlier onset (decreased latency), a greater total incidence, or a faster growth rate of mammary tumors. One hundred C3H/HeJ mice were exposed in circularly polarized waveguides (CWG) for 18 months (20 h/day, 7 days/wk) to continuous-wave, 2450 MHz RFR at a whole body average specific absorption rate (SAR) of 0.3 W/kg; 100 mice were sham exposed. Before exposure, SARs were determined calorimetrically; during experimentation, SARs were monitored by differential power measurement. All animals were visually inspected twice daily and were removed from the CWG cages for a weekly inspection, palpation, and weighing. From the time of detection, tumor size was measured weekly. Animals that died spontaneously, became moribund, or mere killed after 18 months of exposure were completely necropsied; tissues were fixed and subjected to histopathological evaluations. Results showed no significant difference in weight profiles between sham-irradiated and irradiated mice. Concerning mammary carcinomas, there was no significant difference between groups with respect to palpated tumor incidence (sham = 52%; irradiated = 44%), latency to tumor onset (sham = 62.3 +/- 1.2 wk; irradiated = 64.0 +/- 1.6 wk), and rate of tumor growth. In general, histopathological examination revealed no significant differences in numbers of malignant, metastatic, or benign neoplasms between the two groups; a significantly greater incidence of alveolar-bronchiolar adenoma in the sham-irradiated mice was the only exception. In addition, survival analysis showed no significant difference in cumulative percent survival between sham and irradiated animals. Thus, results indicate that under the conditions of this study, long-term, tow-level exposure of mammary-tumor-prone mice to 2450 MHz RFR did not affect mammary tumor incidence, latency to tumor onset, tumor growth rate, or animal longevity when compared with sham-irradiated controls. (C) 1998 Wiley-Liss, Inc. C1 Trinity Univ, Dept Biol, San Antonio, TX 78212 USA. Operat Technol Corp, San Antonio, TX USA. USAF, Armstrong Lab, Brooks AFB, TX USA. Pathol Associates Int, Frederick, MD USA. RP Frei, MR (reprint author), Trinity Univ, Dept Biol, 715 Stadium Dr, San Antonio, TX 78212 USA. EM frei@rfr.brooks.af.mil NR 35 TC 43 Z9 45 U1 0 U2 2 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1998 VL 19 IS 1 BP 20 EP 31 PG 12 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA YP907 UT WOS:000071328000002 PM 9453703 ER PT J AU Adair, ER Kelleher, SA Mack, GW Morocco, TS AF Adair, ER Kelleher, SA Mack, GW Morocco, TS TI Thermophysiological responses of human volunteers during controlled whole-body radio frequency exposure at 450 MHz SO BIOELECTROMAGNETICS LA English DT Article DE thermoregulation; sweating; metabolic rate; body temperature; thermal sensation ID MICROWAVES; DOSIMETRY; RADIATION; FIELDS AB Thermoregulatory responses of heat production and heat loss were measured in seven adult volunteers (four women and three men. aged 21-57 yr) during 45-min dorsal exposures of the whole body to 450 MHz continuous wave radio frequency (RF) fields. Two power densities (PD) (local peak PD = 18 and 24 mV/cm(2); local peak specific absorption rate = 0.320 [W/kg]/[mW/cm(2)]) were tested in each of three ambient temperatures (T(a) = 24, 28, and 31 degrees C) plus T(a) controls (no RF). No changes in metabolic heat production occurred under any exposure conditions. Vigorous increases in sweating rate on back and chest, directly related to both T(a) and PD, cooled the skin and ensured efficient regulation of the deep body (esophageal) temperature to within 0.1 degrees C of the normal level. Category judgments of thermal sensation, comfort, sweating, and thermal preference usually matched the measured changes in physiological responses. Some subtle effects related to gender were noted that confirm classic physiological data. Our results indicate that dorsal exposures of humans to a supra-resonant frequently of 450 MHz at local peak specific absorption rates up to 7.68 W/kg are mildly thermogenic and are counteracted efficiently by normal thermophysiologic heat loss mechanisms, principally sweating. (C) 1998 Wiley-Liss, Inc.double dagger. C1 USAF, Armstrong Lab, OER, Brooks AFB, TX 78235 USA. John B Pierce Lab Inc, New Haven, CT USA. RP Adair, ER (reprint author), USAF, Armstrong Lab, OER, 8308 Hawks Rd, Brooks AFB, TX 78235 USA. EM eleanor.adair@aloer.brooks.af.mil NR 41 TC 42 Z9 42 U1 1 U2 4 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1998 VL 19 IS 4 BP 232 EP 245 DI 10.1002/(SICI)1521-186X(1998)19:4<232::AID-BEM5>3.0.CO;2-2 PG 14 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA ZH987 UT WOS:000073168300004 PM 9581966 ER PT J AU Jauchem, JR Seaman, RL Lehnert, HM Mathur, SP Ryan, KL Frei, MR Hurt, WD AF Jauchem, JR Seaman, RL Lehnert, HM Mathur, SP Ryan, KL Frei, MR Hurt, WD TI Ultra-wideband electromagnetic pulses: Lack of effects on heart rate and blood pressure during two-minute exposures of rats SO BIOELECTROMAGNETICS LA English DT Article DE radiofrequency radiation; heart rate; blood pressure; cardiovascular system ID RADIATION AB Exposure to fast-rise-time ultra-wideband (UWB) electromagnetic pulses has been postulated to result in effects on biological tissue (including the cardiovascular system). In the current study, 10 anesthetized Sprague-Dawley rats were exposed to pulses produced by a Sandia UWB pulse generator (average values of exposures over three different pulse repetition rates: rise time, 174-218 ps; peak E field, 87-104 kV/m; pulse duration, 0.97-0.99 ns). Exposures to 50, 500 and 1000 pulses/s resulted in no significant changes in heart rate or mean arterial blood pressure measured every 30 s during 2 min of exposure and for 2 min after the exposure. The results suggest that acute UWB whole-body exposure under these conditions does not have an immediate detrimental effect on these cardiovascular system variables in anesthetized rats. (C) 1998 Wiley-Liss, Inc. C1 USAF, Radiofrequency Radiat Branch, Directed Energy Bioeffects Div, Human Effectiveness Directorate,Res Lab, Brooks AFB, TX 78235 USA. USAF, McKesson BioServ, Walter Reed Army Inst Res, Med Res Detachment,Microwave Bioeffects Br, Brooks AFB, TX 78235 USA. Trinity Univ, Dept Biol, San Antonio, TX 78212 USA. RP Jauchem, JR (reprint author), AFRL, HEDR, 8308 Hawks Rd, Brooks AFB, TX 78235 USA. EM james.jauchem@aloer.brooks.af.mil NR 20 TC 18 Z9 19 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 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1998 VL 19 IS 5 BP 330 EP 333 DI 10.1002/(SICI)1521-186X(1998)19:5<330::AID-BEM7>3.0.CO;2-2 PG 4 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA ZW448 UT WOS:000074412000007 PM 9669547 ER PT J AU Walters, TJ Ryan, KL Belcher, JC Doyle, JM Tehrany, MR Mason, PA AF Walters, TJ Ryan, KL Belcher, JC Doyle, JM Tehrany, MR Mason, PA TI Regional brain heating during microwave exposure (2.06 GHz), warm-water immersion, environmental heating and exercise SO BIOELECTROMAGNETICS LA English DT Article DE cortex; electromagnetic fields; heat stress; hypothalamus; thermoregulation; nonuniform heating ID RATS; TEMPERATURE AB Nonuniform heating may result from microwave (MW) irradiation of tissues and is therefore important to investigate in terms of health and safety issues. Hypothalamic (T-hyp), cortical (T-ctx), tympanic (T-ty), and rectal (T-re) temperatures were measured in rats exposed in the far field, k-polarization (i.e., head pointed toward the transmitter horn and E-field in vertical direction) to two power densities of 2.06 GHz irradiation. The high-power density (HPM) was 1700 mW/cm(2) [specific absorption rate (SAR): hypothalamus 1224 W/kg; cortex 493 W/kg]; the low-power density (LPM) was 170 mW/cm(2) (SAR: hypothalamus 122.4 W/kg; cortex 49.3 W/kg). The increase (rate-of-rise, in degrees C/s) in T-hyp was significantly greater than those in T-ctx or T-re when rats were exposed to HPM. LPM produced more homogeneous heating. Quantitatively similar results were observed whether rats were implanted with probes in two brain sites or a single probe in one or the other of the two sites. The qualitative difference between regional brain heating was maintained during unrestrained exposure to HPM in the h-polarization (i.e., body parallel to magnetic field). To compare the temperature changes during MW irradiation with those produced by other modalities of heating, rats were immersed in warm water (44 degrees C, WWI); exposed to a warm ambient environment (50 degrees C, WSED); or exercised on a treadmill (17 m/min 8% grade) in a warm ambient environment (35 degrees C, WEX). WWI produced uniform heating in the regions measured. Similar rates-of-rise occurred among regions following WSED or WEX, thus maintaining the pre-existing gradient between T-hyp and T-ctx. These data indicate that HPM produced a 2-2.5-fold difference in the rate-of-heating within brain regions that were separated by only a few millimeters. In contrast more homogeneous heating was recorded during LPM or nonmicrowave modalities of heating. (C) 1998 Wiley-Liss, Inc. C1 Syst Res Labs Inc, San Antonio, TX USA. Trinity Univ, Dept Biol, San Antonio, TX USA. Armstrong Lab, Radiofrequency Radiat Div, Brooks AFB, TX 78235 USA. RP Walters, TJ (reprint author), USAF, AL, OERB, Bldg 1182,8308 Hawks Rd, Brooks AFB, TX 78235 USA. EM thomas.walters@aloer.brooks.af.mil NR 22 TC 10 Z9 11 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 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PY 1998 VL 19 IS 6 BP 341 EP 353 DI 10.1002/(SICI)1521-186X(1998)19:6<341::AID-BEM2>3.3.CO;2-E PG 13 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA 114TD UT WOS:000075624400002 PM 9738525 ER PT J AU Burton, MP Schneider, BG Brown, R Escamilla-Ponce, N Gulley, ML AF Burton, MP Schneider, BG Brown, R Escamilla-Ponce, N Gulley, ML TI Comparison of histologic stains for use in PCR analysis of microdissected, paraffin-embedded tissues SO BIOTECHNIQUES LA English DT Article ID AMPLIFICATION AB We evaluated the effect of six different histologic stains on the productivity of PCR amplification of DNA isolated from paraffin-embedded tissue samples. The tissue was collected from glass slides by microdissection techniques, whereby tiny portions of tissue are visually identified through a microscope and selectively resected for subsequent DNA extraction and PCR amplification. We found that the success of PCR amplification depended on the type of histologic stain that was used to facilitate microscopic visualization of the undeparaffinized tissue section. The best results were obtained with methyl green and nuclear fast red, while Wright's stain yielded less PCR product. Two other stains, Evans blue and light-green SF yellowish (also known as the counterstain for geomori methenamine silver stain) yielded sufficient PCR products; however, their staining characteristics did not afford satisfactory visualization of nuclear chromatin to discriminate between benign and malignant cells. Our most significant finding was that a commonly used histologic stain, hematoxylin, failed to produce DNA templates that could be consistently amplified by PCR. In conclusion, it is prudent to avoid hematoxylin stains when preparing tissues as starting material for PCR. Among the remaining five strains that were evaluated, the best choice depends on the differential staining characteristics of the cells to be dissected. C1 Univ Texas, Hlth Sci Ctr, Dept Pathol, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Audie L Murphy Mem Vet Hosp, San Antonio, TX 78284 USA. Louisiana State Univ, Med Ctr, New Orleans, LA USA. RP Gulley, ML (reprint author), Univ Texas, Hlth Sci Ctr, Dept Pathol, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. FU NCI NIH HHS [R29 CA63308] NR 8 TC 59 Z9 65 U1 0 U2 3 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD JAN PY 1998 VL 24 IS 1 BP 86 EP + PG 6 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA YQ698 UT WOS:000071414300018 PM 9454959 ER PT B AU Kerans, RJ Parthasarathy, TA AF Kerans, RJ Parthasarathy, TA BE Takeda, N Sheppard, LM Kon, J TI Crack deflection in ceramic composites and fiber coating design SO CERAMIC MATERIAL SYSTEMS WITH COMPOSITE STRUCTURES: TOWARDS OPTIMUM INTERFACE CONTROL AND DESIGN LA English DT Proceedings Paper CT Japan-Fine-Ceramics-Center International Workshop in Fine Ceramics 98 CY MAR 12-13, 1998 CL NAGOYA, JAPAN SP Japan Fine Ceram Ctr, Japan Keirin Assoc 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. Oxidation resistant alternatives do not have such a fortuitous suite of properties and will require careful microstructural and composite system design to perform equivalent functions. The rational design of alternative fiber coatings is facilitated by detailed knowledge 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, modeling and testing of alternative fiber coating systems. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RP Kerans, RJ (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA BN 1-57498-065-3 PY 1998 BP 209 EP 220 PG 12 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BL99W UT WOS:000077407200019 ER PT J AU Vasudev, R Novicki, SW AF Vasudev, R Novicki, SW TI SubDoppler polarization spectroscopy of OH ejected by vibrational state-selected trans HONO((A)over-tilde(1)A ''): OH vector correlations, energy correlation between coincident OH,NO pairs, and energy transfer pathways SO CHEMICAL PHYSICS LA English DT Article ID PHOTODISSOCIATION DYNAMICS; MOTIONAL ANISOTROPY; NO FRAGMENT; HONO; DISSOCIATION; PREDISSOCIATION; RESONANCES; SPECTRUM; S-1 AB Specific vibrational states (0(0), 2(n), n = 1-4) of trans HONO((A) over tilde) are excited with a polarized tunable laser and selected rotational states of the ejected OH fragment are probed by subDoppler polarization spectroscopy. The fragment recoil velocity and vector correlations obtained from the analysis of the Doppler profiles are used to deduce the internal energy content of the coincident NO cofragment, and to elucidate energy transfer pathways. These findings, together with our earlier results, are interpreted in terms of an (A) over tilde state potential energy surface in which: (1) the N=O coordinate is coupled to the recoil O-N coordinate; (2) there is a bottleneck in the exit channel and an insignificant exit-channel energy barrier; (3) there is significant angular dependence of the minimum energy path between the recoiling fragments; and (4) there is a coupling of the N=O stretch (nu(2)) with the HON angle bending (nu(3)) vibration. (C) 1998 Elsevier Science B.V. C1 Mississippi State Univ, Diagnost Instrumentat & Anal Lab, Mississippi State, MS 39762 USA. USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. RP Vasudev, R (reprint author), Mississippi State Univ, Diagnost Instrumentat & Anal Lab, Mississippi State, MS 39762 USA. EM vasudev@dial.msstate.edu NR 30 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0301-0104 J9 CHEM PHYS JI Chem. Phys. PD JAN 1 PY 1998 VL 226 IS 1-2 BP 201 EP 215 DI 10.1016/S0301-0104(97)00243-7 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA YQ907 UT WOS:000071436400015 ER PT J AU Epstein, LJE Dorlac, GR AF Epstein, LJE Dorlac, GR TI Cost-effectiveness analysis of nocturnal oximetry as a method of screening for sleep apnea-hypopnea syndrome SO CHEST LA English DT Article DE cost-effectiveness; obstructive sleep apnea; polysomnography; pulse oximetry ID HOME OXIMETRY; NIGHT; POLYSOMNOGRAPHY; DIAGNOSIS; DISORDERS AB Study objective: Determine the utility of nocturnal oximetry as a screening tool for sleep apnea-hypopnea syndrome (SAHS) compared with polysomnography (PSG). Design: Cost-effectiveness analysis based on retrospective review of overnight sleep studies. Setting: United States Air Force tertiary teaching hospital. Patients: One hundred consecutive patients evaluated for SAHS by overnight sleep study. Intervention: Participants underwent PSG and oximetry on the same night. Patients with obstructive sleep apnea had a continuous positive airway pressure trial. Measurements: Oximetry was abnormal when greater than or equal to 10 events per hour occurred. Two criteria were evaluated. A "deep" pattern of >4% change in oxyhemoglobin saturation to less than or equal to 90%, and a "fluctuating" pattern of repetitive short-duration fluctuations in saturation. The diagnostic accuracy of both methods was compared with PSG. Cost-effectiveness of screening oximetry was compared with PSG alone and use of split-night studies. Results: The fluctuating pattern had a greater sensitivity and negative predictive value, while the deep pattern had a greater specificity and positive predictive value. Oximetry screening using the fluctuating pattern was not as sensitive as PSG for detecting patients with mild disease; 17 of 28 patients (61%) with normal oximetry results had treatable conditions detected by PSG, Cost analysis showed that screening oximetry would save $4,290/100 patients but with considerable loss of diagnostic accuracy. Conclusion: Screening oximetry is not cost-effective because of poor diagnostic accuracy despite increased sensitivity using the fluctuating pattern. Greater savings, without loss of diagnostic accuracy, may be achieved through increased utilization of split-night PSGs. C1 Wilford Hall USAF Med Ctr, Dept Pulm & Crit Care Med, Div Med, San Antonio, TX 78236 USA. RP Epstein, LJE (reprint author), Brockton W Roxbury Vet Adm Med Ctr, Div Pulm & Crit Care Med, Cambridge, MA USA. NR 25 TC 58 Z9 60 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 JAN PY 1998 VL 113 IS 1 BP 97 EP 103 DI 10.1378/chest.113.1.97 PG 7 WC Critical Care Medicine; Respiratory System SC General & Internal Medicine; Respiratory System GA YR103 UT WOS:000071458600021 PM 9440575 ER PT J AU Rea, MA AF Rea, MA TI Photic entrainment of circadian rhythms in rodents SO CHRONOBIOLOGY INTERNATIONAL LA English DT Review DE glutamate; immediate early genes; nitric oxide; serotonin; phase shifts ID RAT SUPRACHIASMATIC NUCLEUS; NITRIC-OXIDE SYNTHASE; LIGHT-INDUCED FOS; RETINAL GANGLION-CELLS; WHEEL-RUNNING ACTIVITY; INDUCED PHASE-SHIFTS; DIFFERENTIAL SEROTONERGIC INNERVATION; SUBSTANCE-P IMMUNOREACTIVITY; LATERAL GENICULATE-NUCLEUS; ACID RECEPTOR ANTAGONISTS AB Photic entrainment of circadian rhythms occurs as a consequence of daily, light-induced adjustments in the phase and period of the suprachiasmatic nuclei (SCN) circadian clock. Photic information is acquired by a unique population of retinal photoreceptors, processed by a distinct subset of retinal ganglion cells, and conveyed to the SCN through the retinohypothalamic tract (RHT). RHT neurotransmission is mediated by the release of the excitatory amino acid glutamate acid appears to require the activation of both NMDA- and non-NMDA-type glutamate receptors, the expression of immediate early genes (IEGs), and the synthesis and release of nitric oxide. In addition, serotonin appears to regulate the response of the SCN circadian clock to light through postsynaptic 5-HT1A or 5-ht7 receptors, as well as presynaptic 5-HT1B heteroreceptors on RHT terminals. C1 USAF, Res Lab, Biol Rhythms & Integrat Neurosci Inst, Brooks AFB, TX USA. Univ Texas, Hlth Sci Ctr, Dept Pharmacol, San Antonio, TX 78284 USA. Univ Houston, Dept Biol & Biochem, Houston, TX 77004 USA. RP Rea, MA (reprint author), USAF, Res Lab, Biol Rhythms & Integrat Neurosci Inst, Brooks AFB, TX USA. EM rmea@alcft.brooks.af.mil NR 223 TC 62 Z9 64 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0742-0528 J9 CHRONOBIOL INT JI Chronobiol. Int. PY 1998 VL 15 IS 5 BP 395 EP 423 DI 10.3109/07420529808998699 PG 29 WC Biology; Physiology SC Life Sciences & Biomedicine - Other Topics; Physiology GA 125PK UT WOS:000076245900002 PM 9787933 ER PT J AU Pessa, JE Zadoo, VP Adrian, EK Woodwards, R Garza, JR AF Pessa, JE Zadoo, VP Adrian, EK Woodwards, R Garza, JR TI Anatomy of a "Black eye": A newly described fascial system of the lower eyelid SO CLINICAL ANATOMY LA English DT Article DE black eye; periorbital ecchymosis; malar septum AB The anatomy of a black eye is examined in a series of cadaver dissections in which a previously unreported fascial system of the lower eyelid is identified. This fascia originates at the orbital rim, and is in continuity with the orbital septum and with the periosteum of the orbital floor and anterior maxillary wail. This fascia contributes to the thickened area along the orbital rim called the arcus marginale. At the level of the orbicularis oculi muscle, this fascia was noted microscopically to fuse with a fibrous septa of the superficial cheek fat. This creates one long continuous membrane from the orbital rim above to the cheek skin below. Dye injection techniques show that this membrane is impermeable and traps injected dye in the same place where a black eye forms. After periorbital injury, extravasated hemoglobin pigment is confined to the area above the cutaneous insertion of this membrane. This fascial system has been named the septum malaris: malar describes its origin along the orbital rim of the cheek, and septum further describes the partitioning nature of this ultra-thin membrane. (C) 1998 Wiley-Liss. Inc. C1 Univ Texas, Hlth Sci Ctr, Div Plast Surg, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, Div Plast Surg, San Antonio, TX 78236 USA. Univ Texas, Hlth Sci Ctr, Dept Cellular & Struct Biol, Div Plast Surg, San Antonio, TX 78284 USA. RP Pessa, JE (reprint author), Univ Texas, Hlth Sci Ctr, Div Plast Surg, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. NR 12 TC 19 Z9 19 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 0897-3806 J9 CLIN ANAT JI Clin. Anat. PY 1998 VL 11 IS 3 BP 157 EP 161 DI 10.1002/(SICI)1098-2353(1998)11:3<157::AID-CA2>3.0.CO;2-Q PG 5 WC Anatomy & Morphology SC Anatomy & Morphology GA ZJ020 UT WOS:000073171500002 PM 9579587 ER PT J AU Hojo, S Fujita, J Miyawaki, H Obayashi, Y Takahara, J Bartholomew, DW AF Hojo, S Fujita, J Miyawaki, H Obayashi, Y Takahara, J Bartholomew, DW TI Severe cystic fibrosis associated with a Delta F508/R347H+D979A compound heterozygous genotype SO CLINICAL GENETICS LA English DT Article DE cystic fibrosis; rare mutations; R347H and D979A ID CONGENITAL BILATERAL ABSENCE; REGULATOR CFTR GENE; VAS-DEFERENS; MUTATIONS; MEN AB This report is concerned with twins with cystic fibrosis (CF). They are of mixed parentage: Japanese mother and German father. One case is presented with meconium ileus as a neonate. The other patient did relatively well until the age of 6 years when she was first hospitalized and diagnosed with pulmonary aspergillosis, They have been receiving standard therapies for CF including digestive enzymes, vitamins and periodic antibiotic therapy in the US, At 19 years elf age, they were tested for common mutations and one Delta F508 cystic fibrosis transmembrane conductance regulator (CFTR) allele was found, Further testing of their CFTR gene as well as those of their Japanese mother and grandmother revealed missense mutations in exon 7 (R347H) and exon 16 (D979A). Although the D979A mutant is very rare, this mutation combination seemed to be responsible for severe CF phenotypes. C1 Kagawa Med Univ, Dept Internal Med 1, Kagawa 76107, Japan. USAF, Med Ctr, DNA Diagnost Lab, Washington, DC 20330 USA. RP Fujita, J (reprint author), Kagawa Med Univ, Dept Internal Med 1, 1750-1 Miki Cho, Kagawa 76107, Japan. NR 12 TC 12 Z9 13 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0009-9163 J9 CLIN GENET JI Clin. Genet. PD JAN PY 1998 VL 53 IS 1 BP 50 EP 53 DI 10.1034/j.1399-0004.1998.531530110.x PG 4 WC Genetics & Heredity SC Genetics & Heredity GA ZA074 UT WOS:000072326300013 PM 9550362 ER PT S AU Desjardins, DD Hopper, DG AF Desjardins, DD Hopper, DG BE Hopper, DG TI Defense display market assessment SO COCKPIT DISPLAY V: 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 V - Displays for Defense Applications CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE Int Soc Opt Engn 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 (NVIS) 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 market for direct-view and large-area military displays is presently estimated to be in excess of 242,000. 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 Service 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 (WS) for older display technologies continues to be a growing, pervasive problem throughout DoD, which consequently must leverage the more modern display technologies being developed for civil-commercial markets. C1 USAF, Res Lab, Displays Branch, Wright Patterson AFB, OH 45433 USA. RP Desjardins, DD (reprint author), USAF, Res Lab, Displays Branch, Bldg 248 Rm 300,2255 H St, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2812-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3363 BP 21 EP 32 DI 10.1117/12.321782 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL84Q UT WOS:000076921600003 ER PT S AU Hopper, DG AF Hopper, DG BE Hopper, DG TI Performance specification methodology: introduction and application to displays SO COCKPIT DISPLAY V: 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 V - Displays for Defense Applications CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE Int Soc Opt Engn DE performance specification; displays; flat panel displays; electronics; cycle time; testing; situational awareness AB Acquisition reform is based on the notion that DoD must rely on the commercial marketplace insofar as possible rather than solely looking inward to a military marketplace to meet its needs. This reform forces a fundamental change in the way DoD conducts business, including a heavy reliance on private sector models of change. The key to more reliance on the commercial marketplace is the performance specification (PS). This paper introduces some PS concepts and a PS classification principal to help bring some structure to the analysis of risk (cost, schedule, capability) in weapons system development and the management of opportunities for affordable ownership (maintain/increase capability via technology insertion, reduce cost) in this new paradigm. The DoD shift toward commercial components is nowhere better exemplified than in displays. Displays are the quintessential dual-use technology and are used herein to exemplify these PS concepts and principal. The advent of flat panel displays as a successful technology is setting off an epochal shift in cockpits and other military applications. Displays are installed in every DoD weapon system, and are, thus, representative of a range of technologies where issues and concerns throughout industry and government have been raised regarding the increased DoD reliance on the commercial marketplace. Performance specifications require metrics: the overall metrics of "information-thrust'' with units of Mb/s and "specific info-thrust" with units of Mb/s/kg are introduced to analyze value of a display to the warfighter and affordability to the taxpayer. 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 0 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 0-8194-2812-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3363 BP 33 EP 46 DI 10.1117/12.321789 PG 14 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL84Q UT WOS:000076921600004 ER PT S AU Ghrayeb, J Jackson, TW Hopper, DG Daniels, R AF Ghrayeb, J Jackson, TW Hopper, DG Daniels, R BE Hopper, DG TI Approach of field emission display towards technology status SO COCKPIT DISPLAY V: 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 V - Displays for Defense Applications CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE Int Soc Opt Engn DE field emission display (FED); active matrix liquid crystal display (AMLCD); cathode ray tube (CRT); vacuum fluorescent display (VFD); high gain emission display (HGED); flat panel display (FPD); spindt cathode; thin film diamond; high voltage phosphor; low voltage phosphor AB Flat panel display (FPD) technologies have emerged with smaller depth, size, and power than the cathode ray tube technology that now dominates the display market. Liquid crystal displays in general and active matrix liquid crystal displays (AMLCD), in particular, are the FPD technology of choice. The AMLCD technology is well established has undergone dramatic improvements in the past few years, a trend which is likely to continue. In recent years some potential or want-to-be ("wanabe") alternate technologies, such as field emission displays (FED), high gain emissive displays and vacuum fluorescent displays (VFD), have received substantial investments. For example, the VFD knowledge level has reached technology status as segmented displays in automotive and instrumentation applications. Much work has been done to improve FED technology status, resulting in many attempts to build production quality prototypes. However, no FED has actually gone into production. The question still remains: how close to production are these nascent technologies? This paper will examine how fast field emission displays are progressing towards technology status, which is defined as a display technology that is incorporated in products accepted by the market. This paper will provide a status update of where FED companies are and where they may be heading. Current development programs, recent demonstrations, and possible future product offerings will be discussed. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Ghrayeb, J (reprint author), USAF, Res Lab, 2255 H St,Bldg 248 Rm 300, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2812-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3363 BP 244 EP 255 DI 10.1117/12.321797 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL84Q UT WOS:000076921600026 ER PT S AU Saini, GS Hopper, DG AF Saini, GS Hopper, DG BE Hopper, DG TI Approach of organic light emitting displays (OLED) to technology status SO COCKPIT DISPLAY V: 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 V - Displays for Defense Applications CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE Int Soc Opt Engn DE flat-panel displays; electroluminescent; science; technology; organic; small molecule; polymer AB A display is an electronic component or subsystem used to convert electrical signals into visual imagery in real time suitable for direct interpretation by a human observer. Until recently, the cathode ray tube (CRT) has been the main source of displays. During the last twenty years, it has been determined that alternatives to CRT displays need to found. One of the alternatives was the introduction of flat-panel displays. The term "flat-panel display" is more of a concept than a specific entity. It is a display which is flat and light and may not require a great deal of power. A flat-panel display is often defined in terms of the ideal display, that being: thin form, low volume, even surface, having high resolution, high contrast, sunlight readable, color, low power, and being solid-state, light weight, and low cost. This is easy to conceive but difficult to deliver. The objective is to develop displays with as many desirable characteristics as possible. Flat-panel displays are basically of two types: the light valve type (that needs an external source of light such as a backlight or arc-lamp) and the emissive type (that generate light at the display surface). The light emitting diode (LED) display is of the emissive type. Inorganic LED and electroluminescent (EL) displays have been in use for more than 25 years in one form or the other because of their "inherent" ruggedness and operation over extremely wide temperature ranges. Because of certain limitations of inorganic materials (such as cost, power, and color), LED displays do not dominate the high information content flat-panel display market. A recent discovery of polymer and other organic materials has changed LED prospects. It may now be possible to make organic LED displays that are inexpensive, low-power, and at the same time provide high resolution and full color. If I,resent research objectives are met, organic LEDs mag. revolutionize the flat-panel display market. This paper addresses the various aspects of organic LED technology with particular reference to its useful characteristics, and the technology challenges. The pace of research accomplishments indicate that it will be some years yet before OLEDs succeed in the market place as product components. C1 USAF, Visual Display Syst Branch, Wright Patterson AFB, OH 45433 USA. RP Saini, GS (reprint author), USAF, Visual Display Syst Branch, 2255 H St,Bldg 248 Rm 300, Wright Patterson AFB, OH 45433 USA. NR 0 TC 5 Z9 5 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 0-8194-2812-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3363 BP 288 EP 298 DI 10.1117/12.321798 PG 11 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL84Q UT WOS:000076921600031 ER PT S AU Daniels, R Hopper, DG Beyer, S Peppler, PW AF Daniels, R Hopper, DG Beyer, S Peppler, PW BE Hopper, DG TI High definition displays for realistic simulator and trainer systems SO COCKPIT DISPLAY V: 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 V - Displays for Defense Applications CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE Int Soc Opt Engn DE electronic displays; simulator trainer; mission rehearsal; uninhabited combat aerial vehicle (UCAV); space plane; direct view head down instrument panel; synthetic vision large area display projection displays; solid state laser projector and helmet mounted cueing displays AB Current night simulators and trainers do not provide acceptable levels of visual display performance (performance that would allow ground based trainers to economically replace aircraft flying training) for many air-to-air and air-to-ground training scenarios. Ground training for pilots could be made significantly more realistic, allowing the ground-based curricula to be enlarged. The enhanced ground based training could thee more readily augment actual aircraft flying (training) time. This paper presents the technology need and opportunity to create a new class of immersive simulator-trainer systems having some 210 million pixels characterized especially by a 20-20 visual acuity synthetic vision system having some 150 million pixels. The same new display technology base is needed for planned crew stations for uninhabited combat air vehicles (UCAV), advanced aircraft cockpits and mission crewstations, and for the space plane. C1 USAF, Res Lab, Crew Syst Interface Div, Wright Patterson AFB, OH 45433 USA. RP Daniels, R (reprint author), USAF, Res Lab, Crew Syst Interface Div, 2255 H St Bldg 248 Rm 300, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2812-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3363 BP 407 EP 415 DI 10.1117/12.321796 PG 9 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL84Q UT WOS:000076921600042 ER PT S AU Jackson, TW Byrd, JC Harshbarger, JH AF Jackson, TW Byrd, JC Harshbarger, JH BE Hopper, DG TI Video system characterization SO COCKPIT DISPLAY V: 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 V - Displays for Defense Applications CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE Int Soc Opt Engn DE modulation transfer function; display test and evaluation; avionics display; video test instrument; electronic display; cathode ray tube; flat panel display; time domain reflectometer; video pattern testing AB Video systems in military platforms are typically used to display sensor video and imagery for sensors such as forward looking infrared (FLIR), low light level television (LLLTV), synthetic aperture radar (SAR), and laser radar (LADAR), in addition to graphics and alphanumerics. The performance of these systems may need to be characterized during initial testing or in support a potential upgrade to the sensor. To be able to sense and deliver the best quality of video to the warfighter, it is critical that the system designer have a well-characterized video system, so he or she can make the appropriate performance, cost and schedule tradeoffs. Modulation Transfer Function (MTF) is one of several metrics that can be measured when characterizing a monochrome video system and can be very useful in optimizing the system for either initial design or for an upgrade. The use of MTF in determining resolution throughout a video system, including the application of useful metrics such as MTF area (MTFA) and square root integral (SQRI), is presented in this paper. Issues regarding hybrid video systems, which incorporate both analog and digital components in the video chain, are addressed. Practical methods for MTF testing of both displays and electrical components in the video chain are also presented. The paper discusses the practical application of video test patterns to perform an efficient component evaluation. The use of photometric testing of displays is touched on briefly. And lastly, the final topic to be addressed in this paper is the use of the time domain reflectometer in testing cables in the video chain for impedance mismatches. C1 USAF, Res Lab, Visual Display Syst Branch, HECV, Wright Patterson AFB, OH 45433 USA. RP Jackson, TW (reprint author), USAF, Res Lab, Visual Display Syst Branch, HECV, Bldg 146 Rm 122,2210 8th St Ste 1, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2812-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3363 BP 436 EP 447 DI 10.1117/12.321790 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL84Q UT WOS:000076921600046 ER PT S AU Hopper, DG Meyer, FM AF Hopper, DG Meyer, FM BE Hopper, DG TI Advanced aerospace display interfaces SO COCKPIT DISPLAY V: 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 V - Displays for Defense Applications CY APR 15-17, 1998 CL ORLANDO, FL SP SPIE Int Soc Opt Engn DE display; interface; standard; digital; civil; military; commercial; avionics; vetronics; space AB High-resolution display technologies are being developed to meet the ever-increasing demand for realistic detail. The requirement for evermore visual information exceeds the capacity of fielded aerospace display interfaces. In this paper we begin an exploration of display interfaces and evolving aerospace requirements. Current and evolving standards for avionics, commercial, and flat panel displays are summarized and compared to near term goals for military and aerospace applications. Aerospace and military applications prior to 2005 up to UXGA and digital HDTV resolution can be mer. by using commercial interface standard developments. Advanced aerospace requirements require yet higher resolutions (2560 x 2048 color pixels, 5120 x 4096 color pixels at 85 Hz, etc.) and necessitate the initiation of discussion herein of an "ultra digital interface standard (UDIS)" which includes "smart interface" features such as large memory and blazingly fast resizing microcomputer. Interface capacity, I-T, increased about 10(5) from 1973 to 1998; 10(2) more is needed for UDIS. 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 0 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 0-8194-2812-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3363 BP 448 EP 459 DI 10.1117/12.321791 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL84Q UT WOS:000076921600047 ER PT J AU Katta, VR Jones, EG Roquemore, WM AF Katta, VR Jones, EG Roquemore, WM TI Modeling of deposition process in liquid fuels SO COMBUSTION SCIENCE AND TECHNOLOGY LA English DT Article DE fuels; oxidation chemistry; thermal-stability; modeling; deposition ID THERMAL-STABILITY; JET FUELS; CHEMISTRY; BLENDS AB The thermal stability of jet fuels results from a complex set of chemical reactions, and the deposition process is further complicated by physical mechanisms such as agglomeration and solvation. Although a vast amount of experimental data has been obtained by several researchers, the specific mechanisms responsible for thermal degradation of fuels and the consequent deposit-formation process are still largely unknown. This is primarily due to the fact that the fluid how and the heat transfer which influence the deposition process vary significantly from experiment to experiment. It is thought that Computational Fluid Dynamics with Chemistry (CFDC) models can be used to correlate the data obtained from a number of experiments and, thereby, explore this large data base to aid the understanding of the deposition phenomenon. The success of this approach depends on the accuracy of the global-chemistry models used in the CFDC codes. Recent experiments on blended fuel prepared by mixing a hydrotreated fuel with a non-hydrotreated one suggest that the thermal stability of the blend cannot be linearly extrapolated from the thermal-stability characteristics of the neat fuels. The global-chemistry models developed previously are found to be insufficient for the simultaneous prediction of deposition and oxidation rates associated with the blended fuel; however, a nine-step model developed most recently appears to yield qualitatively correct results. To improve the predictive capabilities of this model, the rate expressions for the bulk-fuel reactions are modified by taking the antioxidant behavior in jet fuels into account. The resulting modified nine-step global-chemistry model yielded the experimentally observed thermal stability characteristics for the blended fuels. Predictions made for higher flow-rate and temperature conditions also matched well with the experimental data. Overall, the modified nine-step global-chemistry model is found not only to improve the accuracy in predicting quantities such as oxygen consumption and surface deposits but also to provide additional capabilities for predicting quantities such as hydroperoxides and bulk insolubles. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Katta, VR (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 36 TC 12 Z9 12 U1 0 U2 8 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0010-2202 J9 COMBUST SCI TECHNOL JI Combust. Sci. Technol. PY 1998 VL 139 IS 1-6 BP 75 EP 111 DI 10.1080/00102209808952082 PG 37 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Energy & Fuels; Engineering GA 176NE UT WOS:000079157100005 ER PT J AU Kaltz, TL Long, LN Micci, MM Little, JK AF Kaltz, TL Long, LN Micci, MM Little, JK TI Supercritical vaporization of liquid oxygen droplets using molecular dynamics SO COMBUSTION SCIENCE AND TECHNOLOGY LA English DT Article DE droplets; vaporization; supercritical; molecular dynamics ID COMBUSTION; SIMULATION; WATER AB The complete vaporization of a three-dimensional submicron liquid oxygen (LOX) droplet into quiescent environments comprised of either hydrogen or helium has been simulated using molecular dynamics. The environment pressures and temperatures ranged from 2 to 20 MPa and 200 to 300 K, respectively. Droplet vaporization rates and thermodynamic property histories were obtained. Results show that at low to moderate pressures the droplet remains spherical and retains a distinct temperature profile throughout the entire vaporization process. In contrast, at very high pressures, the droplet vaporizes in a could-like manner with vanishing surface tension. Droplet temperature histories show that the quasi-steady approximation is valid even when the environment pressure is above the critical pressure of either chemical species. In addition, the environment pressures required to cause the observed transition in vaporization behavior were well above the pure species' critical pressures, which confirms that many of the assumptions used in subcritical droplet evaporation analyses may be valid at pressures much higher than the critical pressure of oxygen. It was also found that significant concentration of the gas phase species was present in the droplet even at moderate pressures. C1 Penn State Univ, Dept Aerosp Engn, University Pk, PA 16802 USA. USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Micci, MM (reprint author), Penn State Univ, Dept Aerosp Engn, University Pk, PA 16802 USA. NR 30 TC 25 Z9 26 U1 1 U2 8 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0010-2202 J9 COMBUST SCI TECHNOL JI Combust. Sci. Technol. PY 1998 VL 136 IS 1-6 BP 279 EP + DI 10.1080/00102209808924174 PG 25 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Energy & Fuels; Engineering GA 131TV UT WOS:000076592100013 ER PT J AU Simpson, JR Montgomery, DC AF Simpson, JR Montgomery, DC TI The development and evaluation of alternative generalized M-estimation techniques SO COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION LA English DT Article DE robust regression estimation; efficiency; breakdown; bounded influence; outliers; estimates of leverage; iteratively reweighted least squares; Monte Carlo simulation ID BOUNDED-INFLUENCE; REGRESSION AB Least squares estimation is a widely used regression technique. The presence of outliers in data can have an adverse effect on least squares estimates, resulting in a model that does not adequately fit the bulk of the data. Robust regression techniques have been proposed as an alternative to least squares when outliers are present. We develop and evaluate new robust regression procedures and compare their performance to the best alternatives currently available in terms of efficiency, breakdown, and bounded influence. We offer the better performing alternatives as possible methods for use in a robust regression scenario. C1 USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. Arizona State Univ, Dept Ind Engn, Tempe, AZ 85287 USA. NR 13 TC 4 Z9 4 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0361-0918 J9 COMMUN STAT-SIMUL C JI Commun. Stat.-Simul. Comput. PY 1998 VL 27 IS 4 BP 999 EP 1018 DI 10.1080/03610919808813522 PG 20 WC Statistics & Probability SC Mathematics GA 132YB UT WOS:000076658200008 ER PT J AU Simpson, JR Montgomery, DC AF Simpson, JR Montgomery, DC TI A performance-based assessment of robust regression methods SO COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION LA English DT Article DE robust regression estimation; efficiency; breakdown; bounded influence; outliers; estimates of leverage; iteratively reweighted least squares; Monte Carlo simulation ID HIGH BREAKDOWN AB A number of robust regression techniques have been proposed as alternatives to least squares when outliers are present in data. No single robust technique is universally accepted as the best. Techniques exhibit strengths and weaknesses depending on the percentage of outliers present, and the location of the outliers in the regressor space. Also, robust techniques perform quite differently when no outliers are present. The purpose of this paper is to evaluate existing and proposed robust methods relative to their performance on a comprehensive group of datasets with and without outliers. Monte Carlo simulation is used to generate datasets with varying outlier characteristics. The coefficient estimates generated by the robust methods are compared to the true coefficient values. Techniques are then ranked based on their performance. The best performing methods consist of an existing method and a method proposed in this paper. C1 USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. Arizona State Univ, Dept Ind Engn, Tempe, AZ 85287 USA. NR 12 TC 11 Z9 11 U1 0 U2 1 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0361-0918 J9 COMMUN STAT-SIMUL C JI Commun. Stat.-Simul. Comput. PY 1998 VL 27 IS 4 BP 1031 EP 1049 DI 10.1080/03610919808813524 PG 19 WC Statistics & Probability SC Mathematics GA 132YB UT WOS:000076658200010 ER PT J AU Grier, SL Bryant, LW AF Grier, SL Bryant, LW TI The case for desktops SO COMMUNICATIONS OF THE ACM LA English DT Article C1 USAF Acad, Dept Comp Sci, Colorado Springs, CO 80840 USA. RP Grier, SL (reprint author), USAF Acad, Dept Comp Sci, Colorado Springs, CO 80840 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 0001-0782 J9 COMMUN ACM JI Commun. ACM PD JAN PY 1998 VL 41 IS 1 BP 70 EP 71 DI 10.1145/268092.268120 PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA YN627 UT WOS:000071189000014 ER PT J AU Bisnett, T Anzueto, A Andrade, FH Rodney, GG Napier, WR Levine, SM Maxwell, LC Mureeba, P Derdak, SD Grisham, MB Jenkinson, SG AF Bisnett, T Anzueto, A Andrade, FH Rodney, GG Napier, WR Levine, SM Maxwell, LC Mureeba, P Derdak, SD Grisham, MB Jenkinson, SG TI Effect of nitric oxide synthase inhibitor on diaphragmatic function after resistive loading SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR AND INTEGRATIVE PHYSIOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the Society-for-Experimental-Biology on Structure and Function in Comparative Physiology - a Tribute to Pierre Laurent CY MAR 25-26, 1996 CL UNIV LANCASTER, LANCASTER, ENGLAND SP Soc Expt Biol, Anim Respirat & Osmoregulat Grp HO UNIV LANCASTER DE nitric oxide; N-omega-nitro-L-arginine-methyl-ester; diaphragmatic fatigue; resistive loading ID SKELETAL-MUSCLE; REACTIVE OXYGEN; RAT DIAPHRAGM; INVITRO; FLOW AB We studied the effect of a nitric oxide synthase inhibitor, N-omega-Nitro-L-arginine-methyl-ester (L-NAME), on in vitro diaphragmatic function both at rest (control) or after inspiratory resistive loading (IRL). Sprague-Dawley rats were anesthetized, instrumented, and then the following experimental groups: (1) controls; (2) L-NAME (100 mg/kg/body weight intravenously alone); (3) IRL alone; and (4) L-NAME + IRL. The IRL protocol consisted of applying a variable resistor to the inspiratory limb of a two-way valve at 70% of maximal airway pressure until apnea. After the experiment, the animals were sacrificed and diaphragmatic strips were obtained for activity of constitutive nitric oxide synthase (cNOS) and measurements of in vitro contractile properties: tetanic (Po) and twitch tensions (Pt). cNOS activity was significantly decreased in the L-NAME and L- NAME + IRL groups (P less than or equal to 0.05) as compared with control and IRL groups. L-NAME alone did not affect Po or Pt. However, in both IRL groups, with and without was a significant decrease in Po and Pt. This reduction was comparable in both groups. In summary, our data showed that L-NAME resulted in a significant decrease cNOS activity, bur. in vitro contractility was impaired, COMP BIOCHEM PHYSIOL 119A;1:185-190, 1998. (C) 1998 Elsevier Science Inc. C1 Audie L Murphy Mem Vet Hosp Div, S Texas Vet Hlth Care Syst, Pulm Dis Sect 111E, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Physiol, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Med, Div Pulm Dis Crit Care Med, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Louisiana State Univ, Shreveport, LA 71105 USA. RP Anzueto, A (reprint author), Audie L Murphy Mem Vet Hosp Div, S Texas Vet Hlth Care Syst, Pulm Dis Sect 111E, 7400 Merton Minter Blvd, San Antonio, TX 78284 USA. RI Andrade, Francisco/F-1258-2011 OI Andrade, Francisco/0000-0002-2460-5798 NR 26 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1095-6433 J9 COMP BIOCHEM PHYS A JI Comp. Biochem. Physiol. A-Mol. Integr. Physiol. PD JAN PY 1998 VL 119 IS 1 BP 185 EP 190 DI 10.1016/S1095-6433(97)00420-0 PG 6 WC Biochemistry & Molecular Biology; Physiology; Zoology SC Biochemistry & Molecular Biology; Physiology; Zoology GA ZZ685 UT WOS:000074756400022 PM 11253784 ER PT S AU John, R Jira, JR Larsen, JM AF John, R Jira, JR Larsen, JM BE Bucinell, RB TI Effect of stress and geometry on fatigue crack growth perpendicular to fibers in Ti-6Al-4V reinforced with unidirectional SiC fibers SO COMPOSITE MATERIALS: FATIGUE AND FRACTURE, SEVENTH VOLUME SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 7th Symposium on Composites - Fatigue and Fracture CY MAY 07-08, 1997 CL ST LOUIS, MO SP ASTM Comm D30 Composite Mat, ASTM Comm E9 Fatigue & Fracture DE bridging stress-intensity factor center crack; crack growth rate; crack opening displacement; cyclic loading; fatigue crack growth; fiber bridging; life prediction; metal matrix composite; shear lag model; titanium matrix composite ID TITANIUM MATRIX COMPOSITES; FIBROUS COMPOSITES; BRIDGED CRACKS; MECHANICS AB Critical turbine engine and aircraft components fabricated from continuous fiber-reinforced metal matrix composite (MMC) will experience cyclic loads during service, and many of these components typically contain crack initiators. Hence, extensive characterization of the fatigue crack growth behavior of a model MMC ([0](8) SCS-6/Ti-6Al-4V) was initiated by the USAF Wright Laboratory. This paper discusses some of the results of the experimental and analytical investigation of fatigue crack propagation in [0](8) SCS-6/Ti-6Al-4V. Automated fatigue crack growth tests were conducted using middle tension, M(T), specimens at 23 degrees C with a stress ratio of 0.1. During some of the tests, the crack opening displacement profile was measured to verify the stress distributions predicted by fiber-bridging models. The results are also compared with those available for SM1240/Ti-6Al-4V under tension and bending fatigue loading. This study showed that the shear lag model assuming a constant value of tau can be used to predict bridged crack growth perpendicular to fibers in SCS-6/Ti-6Al-4V and SM1240/Ti-6Al-4V over a wide range of stress levels and under tension and bending fatigue loading conditions. The predictions of partially bridged and unbridged crack growth, crack opening displacements, and slip lengths correlated well with the data. The value of the fiber/matrix interfacial shear stress, tau, was the same for SCS-6/Ti-6Al-4V and SM1240/Ti-6Al-4V, implying that the bridging mechanism of the SM1240 fiber is identical to that of the SCS-6 fiber at room temperature; The results also indicate that the onset of fiber failure could be predicted using the bundle strength as the critical value. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP John, R (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 44 TC 7 Z9 7 U1 0 U2 2 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2609-3 J9 AM SOC TEST MATER PY 1998 VL 1330 BP 122 EP 144 DI 10.1520/STP13269S PG 23 WC Mechanics; Materials Science, Composites SC Mechanics; Materials Science GA BM47P UT WOS:000078854000008 ER PT S AU Buchanan, DJ John, R Goecke, KE AF Buchanan, DJ John, R Goecke, KE BE Bucinell, RB TI Influence of temperature and stress ratio on the low-cycle fatigue behavior of Trimarc-1/Ti-6Al-2Sn-4Zr-2Mo SO COMPOSITE MATERIALS: FATIGUE AND FRACTURE, SEVENTH VOLUME SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT 7th Symposium on Composites - Fatigue and Fracture CY MAY 07-08, 1997 CL ST LOUIS, MO SP ASTM Comm D30 Composite Mat, ASTM Comm E9 Fatigue & Fracture DE titanium matrix composite; isothermal; low-cycle fatigue; Walker equation; negative stress ratio; mechanical testing; Trimarc-1; Ti-6A1-2Sn-4Zr-2Mo; wire winding; longitudinal; transverse; fatigue; TMC ID TITANIUM MATRIX COMPOSITES; LIFE PREDICTION AB The results of an experimental investigation of load-controlled isothermal low-cycle fatigue behavior of a titanium matrix composite (TMC) are discussed. The TMC was composed of Ti-6Al-2Sn-4Zr-2Mo matrix (wire) reinforced with silicon-carbide (Trimarc-1)(TM) fibers. The composite panels were constructed by alternating layers of matrix; wire and fiber using a wire-winding technique. The panels were unidirectional with a [0](10) layup and fiber volume fraction approximate to 0.29. The longitudinal fatigue data showed good correlation with other TMC systems at both positive and negative stress ratios. The Walker equation was successful at correlating the longitudinal S-N data for stress ratios R = -1.3 and 0.1, and for predictions at R = 0.5 and 0.7. The maximum fiber stress versus cycles to failure for several unidirectional TMC systems at similar test conditions consolidate to a narrow band, indicating that the life is fiber dominated. The S-N behavior of the TMC, subjected to transverse fatigue loading, was successfully predicted using the matrix S-N data and a net-section model. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Buchanan, DJ (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2609-3 J9 AM SOC TEST MATER PY 1998 VL 1330 BP 199 EP 216 DI 10.1520/STP13273S PG 18 WC Mechanics; Materials Science, Composites SC Mechanics; Materials Science GA BM47P UT WOS:000078854000012 ER PT J AU Pagano, NJ AF Pagano, NJ TI On the micromechanical failure modes in a class of ideal brittle matrix composites. Part 1. Coated-fiber composites SO COMPOSITES PART B-ENGINEERING LA English DT Article DE ceramic-matrix composites (CMCs); interface/interphase; micro-mechanics; coatings ID INTERFACE CRACK; MECHANICAL-PROPERTIES; LAMINATED COMPOSITES; REINFORCED CERAMICS; FRACTURE; STRENGTH; INITIATION; STRESSES; SYSTEMS; ENERGY AB An intensive study is carried out to investigate the veracity of an elasticity model called the axisymmetric damage model (ADM) to predict the micromechanical failure modes in a number of ideal unidirectional composites made from silicon carbide fibers and various glass matrices with uniform fiber spacing. In part 1, the specimens contain two fiber coatings. Detailed experiments are conducted to study the fracture process by observation of surface cracking and through SEM micrographic analysis. Failure scenarios postulated through the ADM are consistent with the observed behavior using the measured constituent properties. Some of the features of the composites predicted in this work are: (1) Numerous matrix microcracks, approximately normal to and bridging the fibers, are observed. For the present materials, matrix crack initiation precedes the onset of nonlinearity of the composite stress-strain curve. A semiempirical model derived earlier and a mechanistic crack growth model are used to study this behavior. (2) Carbon mounds (or mountains), which are roughly triangular in cross-section and have a base width of approximately 5 mu m, occur in the specimens. Their location displays a sensitive dependence on the properties of the glass matrix. The ADM suggests the origin of this phenomenon and the loading condition leading to it. (3) A massive degree of debonding is observed within the interfacial region. Again, the nature of this debonding is quite sensitive to the properties of the glass matrix, among other things. The model results are consistent with debonding initiated by radial tension and having continued growth under shear stress. (4) The progressive matrix cracking process is statistical in nature as the distance between successive microcracks varies considerably with position at their initiation. Calculation of the matrix stress held ahead of the interfacial debond leads to bounds, which surround the experimental observations, on the average spacing as a function of applied and residual stresses. (5) Multiple fiber breaks suggest stress transfer has taken place in some regions such that high values of the redistributed fiber axial stress have developed. It is inferred that such failures can only take place in regions where the interface is continuous, while the model results are consistent with the observed failure stress in the fibers. We conclude with an evaluation of the quality of the model and the definition of future research and data needs required to further solidify our findings. We also offer some comments on the implications with regard to our understanding of the behavior of ceramic matrix composites. The well-controlled microgeometry of these composites and the overall consistency of their behavior with analytical models suggest that they can be regarded as truly pedigreed materials. (C) 1998 Elsevier Science Limited. All rights reserved. C1 USAF, Wright Lab, Mat Directorate, Nonmet Mat Div,Mech & Surface Interact Branch, Wright Patterson AFB, OH 45433 USA. RP Pagano, NJ (reprint author), USAF, Wright Lab, Mat Directorate, Nonmet Mat Div,Mech & Surface Interact Branch, Wright Patterson AFB, OH 45433 USA. NR 62 TC 32 Z9 32 U1 3 U2 10 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 1998 VL 29 IS 2 BP 93 EP 119 DI 10.1016/S1359-8368(97)00002-4 PG 27 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA ZK028 UT WOS:000073277700002 ER PT J AU Pagano, NJ AF Pagano, NJ TI On the micromechanical failure modes in a class of ideal brittle matrix composites. Part 2. Uncoated-fiber composites SO COMPOSITES PART B-ENGINEERING LA English DT Article DE ceramic matrix composites (CMCs); debonding; fracture; unidirectional composites AB Models are presented for the penetration and debonding modes of failure of ceramic matrix composites. Test data on silicon carbide-glass composites with uniform fiber spacing are used to examine the quality of these models for use in the constituent material design problem. Testing of uncoated-fiber composites has provided more conclusive evidence regarding the applicability of the model. (C) 1998 Elsevier Science Limited. All rights reserved. C1 USAF, Wright Lab, Mat Directorate, Nonmet Mat Div,Mech & Surface Interact Branch, Wright Patterson AFB, OH 45433 USA. RP Pagano, NJ (reprint author), USAF, Wright Lab, Mat Directorate, Nonmet Mat Div,Mech & Surface Interact Branch, Wright Patterson AFB, OH 45433 USA. NR 8 TC 12 Z9 12 U1 0 U2 0 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 1998 VL 29 IS 2 BP 121 EP 130 DI 10.1016/S1359-8368(97)00003-6 PG 10 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA ZK028 UT WOS:000073277700003 ER PT J AU Majumdar, BS Matikas, TE Miracle, DB AF Majumdar, BS Matikas, TE Miracle, DB TI Experiments and analysis of fiber fragmentation in single and multiple-fiber SiC/Ti-6Al-4V metal matrix composites SO COMPOSITES PART B-ENGINEERING LA English DT Article DE fibres; fragmentation; stress concentrations ID INTERFACIAL SHEAR-STRENGTH; SIC-FIBER; TENSILE-STRENGTH; MECHANICS AB Single-fiber and multiple-fiber single-ply fragmentation experiments were performed at room temperature on SiC/Ti-6Al-4V specimens, to understand interface shear failure under fragmentation conditions and to assess load-sharing behavior in longitudinally loaded composites. Tensile specimens were instrumented with two acoustic emission sensors and an extensometer to monitor the strain at which fiber breaks occurred. Following testing, the break locations were determined using a novel ultrasonic shear-wave back reflection (SBR) technique. Data analysis was performed using Curtin's exact fiber fragmentation model, wherein the in situ Weibull strength and Weibull modulus of the fiber, and the average shear stress under fragmentation conditions, were determined based on best fit with two essentially independent sets of data from the experiments, i.e. the breaking stress of the fibers, and the fragment length distribution. Results for the SCS-6/Ti-6Al-4V samples are presented in this paper, and they are compared with results from other SiC fibers in the same Ti-alloy matrix. The average shear stress from the fragmentation test was significantly higher than that obtained by push-out tests, and is explained on the basis of high radial clamping stress on the fiber in the immediate vicinity of a fiber break. Experiments were also performed on multi-fiber single-ply specimens. Comparison with the single-fiber results showed evidence of correlated fracture even for the relatively weak interface of the SCS-6 fiber. SBR image and macroscopic slip bands indicate that localized plasticity plays a dominant role in promoting correlated fiber fractures at room temperature, and the mechanism is outlined. (C) 1998 Elsevier Science Limited. All rights reserved. C1 Universal Energy Syst Inc, WL, MLLM, Dayton, OH 45432 USA. Univ Dayton, Res Inst, WL, MLLP, Dayton, OH 45469 USA. USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Majumdar, BS (reprint author), Universal Energy Syst Inc, WL, MLLM, 4401 Dayton Xenia Rd, Dayton, OH 45432 USA. RI Matikas, Theodore/I-2803-2012 NR 41 TC 18 Z9 19 U1 3 U2 7 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 1998 VL 29 IS 2 BP 131 EP 145 DI 10.1016/S1359-8368(97)00004-8 PG 15 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA ZK028 UT WOS:000073277700004 ER PT J AU Czarnecki, GJ AF Czarnecki, GJ TI Estimation of the V-50 using semi-empirical (1-point) procedures SO COMPOSITES PART B-ENGINEERING LA English DT Article DE laminates; semi-empirical procedures; V-50 AB Three semi-empirical procedures are presented to economically estimate the ballistic limit (V-50) of composite laminates. The foundation for each method is based on conservation of energy, with special considerations for energy absorbed by the target and transferred into spallation. For impact velocity increments above the penetration threshold a 1:1 relationship exists between the projectile's initial kinetic energy and a summation of the post-penetration kinetic energies. Spall energy is identified as a significant factor influencing the V-50 estimates. To compensate for the spall's influence, each estimation algorithm involves a unique assumption. In method 1, the spall's energy is assessed by assuming the average spall velocity is equivalent to the projectile's residual velocity. In method 2, the initial theoretical slope of 1.00 is assumed to transition abruptly to 0.82 as the spall's influence becomes significant for normalized impact velocities greater than alpha (a velocity ratio). Finally, in method 3, the kinetic energy required for penetration is assumed constant (regardless of projectile mass). Method 3 is proven specially valuable in that once a V-50 is established for a given impactor geometry and mass, the V-50 for any other mass is easily calculated. Each of the three procedures is developed based on results from sphere impact tests on 32-ply quasi-isotropic graphite-epoxy laminates. Limitations for each of the three methods are identified. The procedures' utility relative to thicker laminates and non-spherical projectiles is also assessed. (C) 1998 Elsevier Science Limited. All rights reserved. C1 USAF, Wright Lab, Vehicle Subsyst Div, FIVS, Wright Patterson AFB, OH 45433 USA. RP Czarnecki, GJ (reprint author), USAF, Wright Lab, Vehicle Subsyst Div, FIVS, Wright Patterson AFB, OH 45433 USA. NR 6 TC 9 Z9 10 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 1998 VL 29 IS 3 BP 321 EP 329 DI 10.1016/S1359-8368(97)00032-2 PG 9 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA ZQ734 UT WOS:000073897700014 ER PT J AU Gummadi, LNB Palazotto, AN AF Gummadi, LNB Palazotto, AN TI Progressive failure analysis of composite cylindrical shells considering large rotations SO COMPOSITES PART B-ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Mechanics of Composites of the McNU 97 Joint ASME/ASCE/SES Mechanics Conference CY JUN 29-JUL 02, 1997 CL NORTHWESTERN UNIV, EVANSTON, IL SP ASME, ASCE, SES HO NORTHWESTERN UNIV ID FINITE-ELEMENT ANALYSIS; DAMAGE; PLATES; SHEAR AB A progressive failure analysis approach is presented for cylindrical shells. A geometrically non-linear finite element formulation (with large rotation capability based on the total Lagrangian approach is used to predict the onset of various failure modes in laminated composite plates and shells. Some of the failure modes considered include matrix cracking, fiber breakage and delamination. Failure relations in terms of 2nd Piola Kirchhoff stresses and changes in the constitutive relations due to large strain are taken into consideration. Load-carrying capabilities of the composite cylindrical shell structures, after the first ply failure, are discussed. (C) 1998 Published by Elsevier Science Limited. All rights reserved. C1 USAF, Dept Aeronaut & Astronaut, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP USAF, Dept Aeronaut & Astronaut, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 15 TC 9 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 EI 1879-1069 J9 COMPOS PART B-ENG JI Compos. Pt. B-Eng. PY 1998 VL 29 IS 5 BP 547 EP 563 DI 10.1016/S1359-8368(98)00010-9 PG 17 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA 130UC UT WOS:000076537900004 ER PT J AU Pagano, NJ AF Pagano, NJ TI On the micromechanical failure modes in a class of ideal brittle matrix composites. Part 2. Uncoated-fiber composites (vol 29B, pg 121, 1998) SO COMPOSITES PART B-ENGINEERING LA English DT Correction C1 USAF, Wright Lab, Mat Directorate, Nonmet Mat Div,Mech & Surface Interact Branch, Wright Patterson AFB, OH 45433 USA. RP Pagano, NJ (reprint author), USAF, Wright Lab, Mat Directorate, Nonmet Mat Div,Mech & Surface Interact Branch, Wright Patterson AFB, OH 45433 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 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 1998 VL 29 IS 6 BP 829 EP 829 PG 1 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA 143ET UT WOS:000077242800016 ER PT J AU Gundel, DB Miracle, DB AF Gundel, DB Miracle, DB TI Transverse tensile behavior of SiC-fiber/Ti-6A1-4V composites - 1. Experimental results SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE cruciform specimen geometry; transverse tensile testing; interface strength; SiC fiber; titanium matrix composites ID MATRIX COMPOSITES; SIC FIBER; STRENGTH; STRESS; SINGLE AB Under transverse tension (loads normal to the fiber axis), fiber/matrix debonding in fiber-reinforced titanium-matrix composites results in reductions in specimen stiffness and ultimate strength, and increased loading of the matrix. The interface structure and chemistry have a strong influence on the debond stress and therefore contribute significantly to the transverse composite behavior. In the present study a cruciform specimen geometry was employed over a range of specimen thicknesses to investigate the remote stress levels where debonding initiates in Ti-6Al-4V composites containing SCS-6 (C+Si coating), SCS-0 (no coating), and Trimarc I (carbon coating) SiC fibers. The different surface conditions of the fibers resulted in a range of remote interface debond stresses with SCS-0 being the strongest and Trimarc I being the weakest. Multiple-fiber, single-ply specimens of the three different fibers revealed that the remote debond stress did not vary for SCS-6 and Trimarc I compared to single-fiber tests, but were slightly lower for SCS-0. Part 2 of this study presents analytical and numerical modeling studies of the local stress state at the interface in relation to the applied stress, and discusses them with regard to these experimental results. Published by Elsevier Science Ltd. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Miracle, DB (reprint author), 2230 10th St,Ste 1, Wright Patterson AFB, OH 45433 USA. NR 25 TC 22 Z9 22 U1 2 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 1998 VL 58 IS 10 BP 1571 EP 1581 DI 10.1016/S0266-3538(97)00217-0 PG 11 WC Materials Science, Composites SC Materials Science GA 140JZ UT WOS:000077085300002 ER PT J AU Chen, JK Medina, DF AF Chen, JK Medina, DF TI The effects of projectile shape on laminated composite perforation SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE composite laminate; impact penetration; progressive damage; smoothed particle hydrodynamics; equation of state ID SMOOTHED PARTICLE HYDRODYNAMICS; PENETRATION; IMPACT; SPH; SIMULATION; FRACTURE; KEVLAR; MODEL AB The development of damage in B/Al composite laminates subjected to high-velocity impact has been investigated by using the smoothed particle hydrodynamics (SPH) method. In lieu of a macrohomogenous, anisotropic medium, the composites are treated as a heterogeneous material. This model of the individual fibers and matrix separately is of importance, especially for predicting detailed damage mechanisms resulting from localized, intensive loadings. The numerical results show that damage in B/Al composite laminates due to high-velocity impact is caused not only by perforation but also by a great deal of delamination. It is also shown that for impact velocities exceeding the ballistic limit, a flat projectile can result in a larger perforation hole and more severe damage to the composite targets than a thick projectile with the same mass. Published by Elsevier Science Ltd. C1 USAF, Res Lab, Technol Assessment & Planning Div, Kirtland AFB, NM 87117 USA. RP USAF, Res Lab, Technol Assessment & Planning Div, Kirtland AFB, NM 87117 USA. NR 32 TC 10 Z9 13 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0266-3538 EI 1879-1050 J9 COMPOS SCI TECHNOL JI Compos. Sci. Technol. PY 1998 VL 58 IS 10 BP 1629 EP 1639 DI 10.1016/S0266-3538(97)00230-3 PG 11 WC Materials Science, Composites SC Materials Science GA 140JZ UT WOS:000077085300008 ER PT J AU Tandon, GP Pagano, NJ AF Tandon, GP Pagano, NJ TI Micromechanical analysis of the fiber push-out and re-push test SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE micromechanical analysis; fiber push-out and re-push test; interfacial properties; critical energy release rate; friction; adhesion ID FRACTURE-MECHANICS APPROACH; BRITTLE-MATRIX COMPOSITES; BIMATERIAL INTERFACES; THEORETICAL-ANALYSIS; MODE; DELAMINATION; FRICTION; CRACKING; CONTACT; ENERGY AB The objective of this work is to employ the variational model of a concentric cylinder to model accurately the fiber push-out (and re-push) test used for evaluation of interfacial properties. In this paper, the detailed stress distributions and load/displacement solutions obtained by considering a variety of interface boundary conditions (such as adhesively bonded frictionally sliding and debonded) are compared with a numerical elasticity solution which uses the material properties of a polyester/epoxy system for which experimental data are also available. The present approach is shown accurately to predict the force versus debond length relationships in the progressive debonding portion of the push-out test while demonstrating a boundary layer effect in the behavior of fiber axial stress near the free surface and interfacial radial and shear stress in the slip region. The apparent debond toughness has been defined by using energy-balance arguments during a critical finite crack extension. The increase in crack-tip driving force with the length of the debond is attributed to crack-tip mode mixity while the magnitude of the release rate of shear energy is observed to be nearly constant. By using the critical shear-energy release rate criterion, the load/displacement response is then predicted during push-out and re-push tests. Finally an estimate of the maximum debond stress, externally applied displacement and the critical debond length are made at the point of instability. All of these estimates are in good agreement with the experimental measurements. Published by Elsevier Science Ltd. C1 USAF, Mat Directorate, AFRL, MLBM, Wright Patterson AFB, OH 45433 USA. AdTech Syst Res Inc, Dayton, OH 45432 USA. RP Pagano, NJ (reprint author), USAF, Mat Directorate, AFRL, MLBM, Wright Patterson AFB, OH 45433 USA. NR 37 TC 28 Z9 29 U1 0 U2 8 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 1998 VL 58 IS 11 BP 1709 EP 1725 DI 10.1016/S0266-3538(98)00037-2 PG 17 WC Materials Science, Composites SC Materials Science GA 146FP UT WOS:000077418700002 ER PT J AU Bechel, VT Sottos, NR AF Bechel, VT Sottos, NR TI A comparison of calculated and measured debond lengths from fiber push-out tests SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE polymer-matrix composites; debonding; fracture; friction; finite-element analysis ID COMPOSITES; MECHANICS; BEHAVIOR; STRESSES AB A procedure involving iterative finite-element analyses has been developed for the accurate prediction of the debond length as a function of force by using the progressive debonding load/deflection data from fiber push-out tests conducted on a polyester/epoxy model composite with a thickness of approximately 2.5 fiber diameters. The finite-element simulation included loads due to chemical shrinkage of the matrix during cure as well as the boundary conditions corresponding to the exact probe and sample Support dimensions. The resulting debond lengths corresponded to within 7% of the measured debond lengths. Fracture energy, was also determined by the finite-element method by computing the change in potential energy when incrementing the interface crack length by 0.1% of the total crack length and subtracting the increase in the energy dissipated by friction. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 AFRL, MLBC, Nonmet Struct Mat Branch, Wright Patterson AFB, OH 45433 USA. Univ Illinois, Dept Theoret & Appl Mech, Champaign, IL 61820 USA. RP Bechel, VT (reprint author), AFRL, MLBC, Nonmet Struct Mat Branch, Bldg 654,2941 P St Suite 1, Wright Patterson AFB, OH 45433 USA. NR 26 TC 18 Z9 18 U1 1 U2 4 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 1998 VL 58 IS 11 BP 1727 EP 1739 DI 10.1016/S0266-3538(98)00038-4 PG 13 WC Materials Science, Composites SC Materials Science GA 146FP UT WOS:000077418700003 ER PT J AU Bechel, VT Sottos, NR AF Bechel, VT Sottos, NR TI The effect of residual stresses and sample preparation on progressive debonding during the fiber push-out test SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE polymer-matrix composites; debonding; fracture; friction; finite-element analysis ID BRITTLE-MATRIX COMPOSITES AB Iterative finite-element analyses have been conducted to determine the debond length as a function of force during progressive debonding in fiber push-out tests. This procedure was applied to data from push-out tests on a steel/ epoxy model composite. During push-out testing this composite debonded from the bottom (support) face of the sample. The modeling allowed debonding from the bottom and included pre-existing debonds caused by resisdual stresses and/or sample preparation. The predicted debond lengths were within 10% of the measured debond lengths. Evidence is also shown that cutting and polishing can cause debonds that are longer than one third of the sample thickness in samples with a relatively small diameter steel fiber. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 AFRL, MLBC, Nonmet Struct Mat Branch, Wright Patterson AFB, OH 45433 USA. Univ Illinois, Dept Theoret & Appl Mech, Champaign, IL 61820 USA. RP Bechel, VT (reprint author), AFRL, MLBC, Nonmet Struct Mat Branch, Bldg 654,2941 P St Suite 1, Wright Patterson AFB, OH 45433 USA. NR 17 TC 15 Z9 17 U1 0 U2 1 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 1998 VL 58 IS 11 BP 1741 EP 1751 DI 10.1016/S0266-3538(98)00039-6 PG 11 WC Materials Science, Composites SC Materials Science GA 146FP UT WOS:000077418700004 ER PT J AU Ahn, BK Curtin, WA Parthasarathy, TA Dutton, RE AF Ahn, BK Curtin, WA Parthasarathy, TA Dutton, RE TI Criteria for crack deflection/penetration criteria for fiber-reinforced ceramic matrix composites SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE ceramic matrix composites; fracture toughness; fiber/matrix interface; crack deflection/penetration; energy criterion ID DISSIMILAR ELASTIC-MATERIALS; INTERFACE; DEFLECTION AB Deflection of a matrix crack at the fiber/matrix interface is the initial mechanism required for obtaining enhanced toughness in ceramic-matrix composites (CMCs). Here, energy, release rates are calculated for matrix cracks that either deflect or penetrate at the interface of an axisymmetric composite as a function of elastic mismatch, fiber volume fraction, and length of the deflected or penetrated crack. The energy release rates for the competing fracture modes are calculated numerically by means of the axisymmetric damage model developed by Pagano, which utilizes Reissner's variational principle and an assumed stress field to solve the appropriate boundary value problems. Crack deflection versus penetration is predicted by using an energy criterion analogous to that developed by He anti Hutchinson. Results show that, for equal crack extensions in deflection and penetration, crack deflection is more difficult for finite crack extension and finite fiber volume fraction than in the He and Hutchinson limit of zero volume fraction and/or infinitesimal crack extension. Allowing for different crack extensions for the deflected and penetrating cracks is shown to have a small effect at larger volume fractions. Fracture-mode data on model composites with well-established constitutive properties show penetration into the fibers (brittle behavior), as predicted by the present criteria for crack extensions larger than 0.2% of the fiber radius and in contrast to the He and Hutchinson criterion, which predicts crack deflection. This result suggests that the latter criterion may over-estimate the prospects for crack deflection in composites with realistic fiber volume fi actions and high ratios of fiber to matrix elastic modulus. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 USA. Wright Lab, MLLM, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Curtin, WA (reprint author), Brown Univ, Div Engn, Providence, RI 02912 USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 13 TC 42 Z9 45 U1 0 U2 13 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 1998 VL 58 IS 11 BP 1775 EP 1784 DI 10.1016/S0266-3538(98)00043-8 PG 10 WC Materials Science, Composites SC Materials Science GA 146FP UT WOS:000077418700007 ER PT J AU Pagano, NJ Schoeppner, GA Kim, R Abrams, FL AF Pagano, NJ Schoeppner, GA Kim, R Abrams, FL TI Steady-state cracking and edge effects in thermo-mechanical transverse cracking of cross-ply laminates SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE composites; transverse cracks; micromechanics; steady-state cracking; free-edge ID ENERGY-RELEASE RATE; STIFFNESS REDUCTION; CONSTRAINED CRACKING; CONSERVATION LAWS; UNIAXIAL TENSION; BRITTLE-MATRIX; STRESS FIELDS; COMPOSITES; GLASS; MICROCRACKING AB Composites for, space applications such as advanced satellites will require the use of new and/or improved materials so that more stringent dimensional stability requirements call be met. In this work, we study the effect of ply-level initiation of damage under loading and processing stresses and imposed thermal loading. In particular, included in the study is the prediction and demonstration of a condition of steady-state cracking and the temperature change and loading level necessary to create this damage state, thus leading to the possibility of a predetermined loading range over which layer cracking will plot propagate. We also consider the influence of the free-edges an the initiation of layer transverse cracking and potential microcracking that may develop at the fiber/matrix interface. The condition of constrained edge cracking is demonstrated where cracks develop but do not propagate across the laminate, To accomplish these studies unidirectional composites and various cross-ply laminates of IM7/2250-4 (graphite/bismaleimide) were produced mid characterized. Published by Elsevier Science Ltd. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP Pagano, NJ (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 48 TC 47 Z9 48 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 1998 VL 58 IS 11 BP 1811 EP 1825 DI 10.1016/S0266-3538(98)00047-5 PG 15 WC Materials Science, Composites SC Materials Science GA 146FP UT WOS:000077418700011 ER PT B AU Dettmer, R Bozada, C Jenkins, T Cerny, C DeSalvo, G Ebel, J Gillespie, J Nakano, K Pettiford, C Quach, T Sewell, J Via, GD Welch, R Anholt, R AF Dettmer, R Bozada, C Jenkins, T Cerny, C DeSalvo, G Ebel, J Gillespie, J Nakano, K Pettiford, C Quach, T Sewell, J Via, GD Welch, R Anholt, R BE Ren, F Abernathy, CR Buckley, DN Pearton, SJ Chu, SNG Parsey, JM Zolper, JC TI Thermal considerations for heterojunction bipolar transistors SO COMPOUND SEMICONDUCTOR POWER TRANSISTORS AND STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS (SOTAPOCS XXIX) SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Compound Semiconductor Power Transistors / 29th State-of-the-Art Program on Compound Semiconductors at the 149th Meeting of the Electrochemical-Society CY NOV 01-06, 1998 CL BOSTON, MA SP Electrochem Soc, Electr Div AB An overview of thermal management of heterojunction bipolar transistors (HBTs) is given. The paper includes a description of the self-heating effects observed in HBTs, common thermal management techniques, and the determination of thermal resistance. In addition, results from simulations and experiments concerning the layout and fabrication of HBTs with respect to the thermal properties will be reviewed. C1 USAF, Res Lab, SNDD, Wright Patterson AFB, OH 45433 USA. RP Dettmer, R (reprint author), USAF, Res Lab, SNDD, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-222-2 J9 ELEC SOC S PY 1998 VL 98 IS 12 BP 104 EP 116 PG 13 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary SC Electrochemistry; Engineering; Materials Science GA BL94F UT WOS:000077242700012 ER PT S AU Seaford, ML Tomich, DH Eyink, KG Lampert, WV Ejeckam, FE Lo, YH AF Seaford, ML Tomich, DH Eyink, KG Lampert, WV Ejeckam, FE Lo, YH BE Melloch, M Reed, MA TI Comparison of MBE grown InSb on CU substrates using different sacrificial layers SO COMPOUND SEMICONDUCTORS 1997 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 24th IEEE International Symposium on Compound Semiconductors CY SEP 08-11, 1997 CL SAN DIEGO, CALIFORNIA SP IEEE, Motorola, USN, Off Naval Res, Siemens, Aixtron, EPI AB InSb epitaxial layers with approximately 15% lattice mismatched to GaAs were grown on a conventional GaAs substrate and compliant universal (CU) substrates using various sacrificial layers. Transmission electron microscopy studies showed dislocation free InSb films grown on the CU substrate using the AlGaAs sacrificial layer, whereas the InSb films on the normal GaAs substrate and the CU substrate with the InGaP sacrificial layer exhibited dislocation densities as high as 10(11) cm(-2). Reciprocal space maps of the (004) peak for the dislocation free InSb layer revealed a large mosaic spread of similar to 0.25 degrees. Using atomic force microscopy on the dislocation free InSb layer, the mosaic spread was found to be generated by a periodic surface undulation with a three micron period and 700 Angstrom amplitude. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Cornell Univ, Sch Elect Engn, Ithaca, NY 14853 USA. RP Seaford, ML (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 6 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0556-8 J9 INST PHYS CONF SER PY 1998 VL 156 BP 29 EP 32 DI 10.1109/ISCS.1998.711536 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Multidisciplinary; Physics, Condensed Matter SC Engineering; Physics GA BL23S UT WOS:000074779700006 ER PT S AU Dorsey, DL Mahalingam, K Venkat, R AF Dorsey, DL Mahalingam, K Venkat, R BE Melloch, M Reed, MA TI A comprehensive atomic-level simulator for AlGaAs/GaAs (001) MBE SO COMPOUND SEMICONDUCTORS 1997 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 24th IEEE International Symposium on Compound Semiconductors CY SEP 08-11, 1997 CL SAN DIEGO, CALIFORNIA SP IEEE, Motorola, USN, Off Naval Res, Siemens, Aixtron, EPI AB A comprehensive, quantitatively accurate, atomic-level simulator for AlGaAs/GaAs (001) MBE has been developed. The kinetic Monte Carlo method was applied within the solid-on-solid approximation, explicitly accounting for deposition, desorption and surface diffusion of both the group III and group V species. In contrast to previous efforts, the kinetic parameters of the model (neighbor interaction energies) were determined by matching model results to gallium desorption transients measured by desorption mass spectrometry (DMS) during GaAs/AlGaAs/GaAs heterointerface formation. The model reproduces these complex transients, and predicts the stoichiometry profile near the GaAs/AlGaAs heterointerface. C1 USAF, Res Lab, WL, MLPO,Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Dorsey, DL (reprint author), USAF, Res Lab, WL, MLPO,Mat & Mfg Directorate, Bldg 651,3005 P St Ste 6, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0556-8 J9 INST PHYS CONF SER PY 1998 VL 156 BP 147 EP 150 DI 10.1109/ISCS.1998.711601 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Multidisciplinary; Physics, Condensed Matter SC Engineering; Physics GA BL23S UT WOS:000074779700034 ER PT S AU Schuermeyer, F Cheskis, D Goldman, RS Wieder, HH AF Schuermeyer, F Cheskis, D Goldman, RS Wieder, HH BE Melloch, M Reed, MA TI Photoconduction studies on InGaAs HEMTs SO COMPOUND SEMICONDUCTORS 1997 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 24th IEEE International Symposium on Compound Semiconductors CY SEP 08-11, 1997 CL SAN DIEGO, CALIFORNIA SP IEEE, Motorola, USN, Off Naval Res, Siemens, Aixtron, EPI ID INGAAS/INALAS QUANTUM-WELLS AB Photoconduction measurements made on In(0.53)G(0.47)As channel HEMTs indicate that the threshold energy for photoconduction corresponds to the bandgap of the quantum well and the absorption edge of the substrate. Many interband transitions are observed which can be correlated with the electronic subbands of the quantum well. Strong confinement of photogenerated holes is associated with a large modulation of the HEMT threshold voltage. C1 Wright Lab, AADD, Wright Patterson AFB, OH 45433 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Anadigics, Warren, NJ USA. RP Schuermeyer, F (reprint author), Wright Lab, AADD, Wright Patterson AFB, OH 45433 USA. RI Goldman, Rachel/J-9091-2012 NR 8 TC 0 Z9 0 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0556-8 J9 INST PHYS CONF SER PY 1998 VL 156 BP 303 EP 306 DI 10.1109/ISCS.1998.711641 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Multidisciplinary; Physics, Condensed Matter SC Engineering; Physics GA BL23S UT WOS:000074779700072 ER PT S AU Smith, SA Wolden, CA Bremser, MD Hanser, AD Davis, RF Lampert, WV AF Smith, SA Wolden, CA Bremser, MD Hanser, AD Davis, RF Lampert, WV BE Melloch, M Reed, MA TI Selective and non-selective etching of GaN, AlGaN, and AlN using an inductively coupled plasma SO COMPOUND SEMICONDUCTORS 1997 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 24th IEEE International Symposium on Compound Semiconductors CY SEP 08-11, 1997 CL SAN DIEGO, CALIFORNIA SP IEEE, Motorola, USN, Off Naval Res, Siemens, Aixtron, EPI AB The etching behavior of gallium nitride (GaN) has been systematically examined in an inductively coupled plasma (ICP) using Cl-2 and Ar as the reagents. Design of experiments (DOE) software was used to optimize the etch rare as well as determine any interactions between the parameters (ICP power, DC bias, and pressure). Interactions were found between the ICP power and pressure and also between the ICP power and DC bias. There were no interactions between the DC bias and pressure. Selective etching of GaN I relative to AIN and Al.28Ga.72N was achieved at low DC biases. At -20 V, the GaN etch rates were 38 rimes greater than AIN and a factor of 10 greater than Al.28Ga.72N. C1 N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Smith, SA (reprint author), N Carolina State Univ, Dept Mat Sci & Engn, Box 7907, Raleigh, NC 27695 USA. RI Davis, Robert/A-9376-2011 OI Davis, Robert/0000-0002-4437-0885 NR 3 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0556-8 J9 INST PHYS CONF SER PY 1998 VL 156 BP 349 EP 352 DI 10.1109/ISCS.1998.711652 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Multidisciplinary; Physics, Condensed Matter SC Engineering; Physics GA BL23S UT WOS:000074779700083 ER PT S AU Bimberg, D Ledentsov, NN Grundmann, M Heinrichsdorff, F Ustinov, VM Kop'ev, PS Alferov, ZI Lott, JA AF Bimberg, D Ledentsov, NN Grundmann, M Heinrichsdorff, F Ustinov, VM Kop'ev, PS Alferov, ZI Lott, JA BE Melloch, M Reed, MA TI Fabry-Perot and vertical cavity surface emitting InAs quantum dot lasers SO COMPOUND SEMICONDUCTORS 1997 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 24th IEEE International Symposium on Compound Semiconductors CY SEP 08-11, 1997 CL SAN DIEGO, CALIFORNIA SP IEEE, Motorola, USN, Off Naval Res, Siemens, Aixtron, EPI ID SELF-ORGANIZED GROWTH; OPTICAL-PROPERTIES; GAAS; ISLANDS; INGAAS; GAIN; HETEROSTRUCTURES; LUMINESCENCE; THRESHOLD; OPERATION AB Quantum dot (QD) edge emitting and vertical cavity lasers are realized using a self-organized growth approach. Threshold current densities at room temperature(RT) of about 60 A/cm(2) for edge emitting and 170 A/cm(2) for vertical cavity lasers are measured. High internal (>96%) and differential (70%) efficiencies are obtained for InGaAs-AlGaAs lasers based on vertically coupled QDs and RT 1 W continuous wave operation is demonstrated. QD lasers exhibit much larger gain, differential gain and smaller linewidth enhancement factor as compared to conventional quantum well devices. C1 Tech Univ Berlin, Inst Festkorperphys, D-10623 Berlin, Germany. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Bimberg, D (reprint author), Tech Univ Berlin, Inst Festkorperphys, D-10623 Berlin, Germany. RI Ustinov, Viktor/J-3545-2013; Grundmann, Marius/D-4229-2012 OI Grundmann, Marius/0000-0001-7554-182X NR 42 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0556-8 J9 INST PHYS CONF SER PY 1998 VL 156 BP 547 EP 552 DI 10.1109/ISCS.1998.711736 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Multidisciplinary; Physics, Condensed Matter SC Engineering; Physics GA BL23S UT WOS:000074779700130 ER PT S AU Lott, JA Noble, MJ AF Lott, JA Noble, MJ BE Melloch, M Reed, MA TI Model of intra and extracavity photodetection for planar resonant cavity light emitting diodes SO COMPOUND SEMICONDUCTORS 1997 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 24th IEEE International Symposium on Compound Semiconductors CY SEP 08-11, 1997 CL SAN DIEGO, CALIFORNIA SP IEEE, Motorola, USN, Off Naval Res, Siemens, Aixtron, EPI ID EMISSION AB A classical model of spontaneous emission in resonant cavity light emitting diodes is developed. The model is based on a plane wave expansion of a randomly distributed ensemble of noninteracting optical dipole emitter pairs placed within a planar microcavity. The model accounts for losses due to leaky guided modes and intracavity absorption. Given an arbitrary device structure, the model predicts the total power emitted, the radiation pattern, and the relative magnitude of photocurrent generated in an intra or extracavity photodetector. Selected modeling results for an example device emitting at 650 nm are included. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Lott, JA (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, 2950 P St Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0556-8 J9 INST PHYS CONF SER PY 1998 VL 156 BP 585 EP 588 DI 10.1109/ISCS.1998.711745 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Multidisciplinary; Physics, Condensed Matter SC Engineering; Physics GA BL23S UT WOS:000074779700139 ER PT J AU Patnaik, SS Lupo, JA Pachter, R AF Patnaik, SS Lupo, JA Pachter, R TI Atomistic modelling of nematic liquid crystals: a study of structure property relationships in steroidal mesogen based liquid crystals SO COMPUTATIONAL AND THEORETICAL POLYMER SCIENCE LA English DT Article DE atomistic modelling; nematic liquid crystals ID COMPUTER-SIMULATION AB In this study we report molecular mechanics calculations designed to predict and interpret structure-property relationships in nematic liquid crystals. A family of liquid crystals with steroidal mesogens were studied and the results were compared with available X-ray data. Low energy conformations of dimers were analysed to provide quantitative information about the local intermolecular interactions and their anisotropic nature. Important contributions to the molecular packing could be identified and the geometry of the dimers and the extent of their positional correlation was successfully related to their:ir observed packing behaviour. By monitoring the relative orientation of the two molecules, a qualitative study of liquid crystalline phase stability was accomplished. Simulations were also carried out with a modified energy function which includes a nematic contribution representing the cumulative intermolecular interactions owing to long range orientational order present in liquid crystals. Along with providing a systematic study of the relative importance of the various competing forces (steric repulsion, attractive forces, long-range electrostatic interactions) in the formation of liquid crystalline phases, this method can also be expected to be useful in predicting mesophase behaviour. (C) 1998 Elsevier Science Led. All rights reserved. C1 USAF, Mat & Mfg Directorate, AFRL MLPJ, Wright Patterson AFB, OH 45433 USA. NR 11 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1089-3156 J9 COMPUT THEOR POLYM S JI Comput. Theor. Polym. Sci. PY 1998 VL 8 IS 1-2 SI SI BP 39 EP 47 DI 10.1016/S1089-3156(98)00011-7 PN 2 PG 9 WC Polymer Science SC Polymer Science GA 107ZE UT WOS:000075240500006 ER PT J AU Clark, DD Feigenbaum, EA Greenberg, D Hartmanis, J Lucky, RW Metcalfe, RM Reddy, R Shaw, M Wulf, W AF Clark, DD Feigenbaum, EA Greenberg, D Hartmanis, J Lucky, RW Metcalfe, RM Reddy, R Shaw, M Wulf, W TI Innovation and obstacles: The future of computing SO COMPUTER LA English DT Editorial Material AB In this multidisciplinary glimpse forward, some of this decade's key players offer opinions on a range of topics, form what has driven progress, to where innovation will come from and to obstacles we have yet to overcome. In this excerpt from "Visions for the Future of the Fields", a panel discussion held at the 10th anniversary of the US Computer Science and Telecommunications Board, experts identify critical issues for various aspects of computing. In the accompanying sidebars, some of the same experts elaborate on points in the panel discussion in mini-essays: David Clark, CSTB chairman, looks at the changes needed, as computing science research comes of age. The current context of computer science, Clark states, is shaped by pst successes and chronic trouble spots. Mary Shaw, Carnegie Mellon University, examines challenges for software system designers. Shaw states that disintermediation, the direct connection of users and their software, has created new problems for software system designers. Robert Lucky, Bellcore, looks at IP dial tone, a new infrastructure for the Internet. Lucky states that data traffic will soon eclipse voice traffic, portending not just a revolution in technology but in the very basis of telecommunication economics. Donald Greenberg, Cornell University, rounds out the essays with an outlook on computer graphics. Greenberg states that by 2025 we will have the technology to produce realistic real-time images at resolutions up to or beyond the limits of our visual perception. Finally, in an interview with William Wulf, president of the US National Academy of Engineering, Computer explores the roots of innovation and the broader societal aspects that will ultimately drive innovation in the near term. C1 MIT, Comp Sci Lab, Cambridge, MA 02139 USA. USAF, Washington, DC 20330 USA. Cornell Univ, Ithaca, NY 14853 USA. BELLCORE, Morristown, NJ 07960 USA. Int Data Grp Inc, Boston, MA 02116 USA. Natl Sci Fdn, Washington, DC 20550 USA. Carnegie Mellon Univ, Sch Comp Sci, Pittsburgh, PA 15213 USA. RP Clark, DD (reprint author), MIT, Comp Sci Lab, Cambridge, MA 02139 USA. NR 0 TC 1 Z9 1 U1 0 U2 3 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0018-9162 J9 COMPUTER JI Computer PD JAN PY 1998 VL 31 IS 1 BP 29 EP + PG 11 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering SC Computer Science GA YP591 UT WOS:000071293400003 ER PT J AU Jensen, D Pramono, E AF Jensen, D Pramono, E TI Method for teaching finite elements which combines the advantages of commercial pre- and postprocessing with student-written software SO COMPUTER APPLICATIONS IN ENGINEERING EDUCATION LA English DT Article DE finite elements; visualization; Patran; stress analysis AB A set of tools is presented which will enhance the teaching of courses in finite element analysis. These tools provide an enhanced learning environment for students by allowing them to write a portion of the solution software while maintaining the advantage of using robust, multifeatured commercial software in the model-building and results visualization stages. (C) 1998 John Wiley & Sons, Inc. C1 USAF Acad, Dept Engn Mech, Colorado Springs, CO 80840 USA. Cadence Design Syst Inc, San Jose, CA 95134 USA. NR 14 TC 7 Z9 7 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1061-3773 J9 COMPUT APPL ENG EDUC JI Comput. Appl. Eng. Educ. PY 1998 VL 6 IS 2 BP 105 EP 114 DI 10.1002/(SICI)1099-0542(1998)6:2<105::AID-CAE6>3.0.CO;2-H PG 10 WC Computer Science, Interdisciplinary Applications; Education, Scientific Disciplines; Engineering, Multidisciplinary SC Computer Science; Education & Educational Research; Engineering GA ZX319 UT WOS:000074503600006 ER PT B AU Barnes, AA AF Barnes, AA GP AMER METEOROL SOC AMER METEOROL SOC AMER METEOROL SOC AMER METEOROL SOC TI USAF and environmental modifications SO CONFERENCE ON CLOUD PHYSICS LA English DT Proceedings Paper CT 14th Conference on Planned and Inadvertent Weather Modification CY AUG 17-21, 1998 CL EVERETT, WA SP Amer Meteorol Soc C1 USAF, Res Lab, VSBE, Hanscom AFB, MA 01731 USA. RP Barnes, AA (reprint author), USAF, Res Lab, VSBE, Hanscom AFB, MA 01731 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 640 EP 643 PG 4 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BM52Y UT WOS:000079027100184 ER PT B AU Lehr, JM Abdalla, MD Schoenberg, JSH Skipper, MC Tyo, JS Burger, JW AF Lehr, JM Abdalla, MD Schoenberg, JSH Skipper, MC Tyo, JS Burger, JW GP IEEE IEEE TI Progress toward a compact, high power ultra-wideband array using gallium arsenide photoconductive semiconductor switches SO CONFERENCE RECORD OF THE 1998 TWENTY-THIRD INTERNATIONAL POWER MODULATOR SYMPOSIUM LA English DT Proceedings Paper CT 23rd International Power Modulator Symposium CY JUN 22-25, 1998 CL RANCHO MIRAGE, CA SP Advisory Grp Electron Devices, Army Res Lab, Army Res Off, Air Force Wright Lab, Naval Surface Warfare Ctr, Sandia Natl Labs, Univ SO CA, Electron Devices Soc IEEE AB There is considerable demand within the technical applications community for sources which produce high power transient radiation. Currently, lateral geometry high power photoconductive semiconductor switches (PCSS) are being developed for use in phased array, ultra-wideband sources. The present source configuration is a stacked blumlein configuration commuted with a PCSS. A new liquid insulating media, HFE-7100, has been demonstrated to have an equivalent voltage hold off capability as sulphur hexafloride, but with greater compatibility to gallium arsenide. Independent low jitter PCSS operation is demonstrated by coupling two independent blumleins into a common load. Measurements of both the system jitter and the isolated jitter of the PCSS switch has been performed. C1 USAF, Res Lab, DEHP, High Power Syst Branch, Kirtland AFB, NM 87117 USA. RP Lehr, JM (reprint author), USAF, Res Lab, DEHP, High Power Syst Branch, 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 0-7803-4244-5 PY 1998 BP 156 EP 159 DI 10.1109/MODSYM.1998.741215 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BM25Z UT WOS:000078189700040 ER PT B AU O'Loughlin, JP Loree, DL AF O'Loughlin, JP Loree, DL GP IEEE IEEE TI Inductance calculations for air core foil wound transformers SO CONFERENCE RECORD OF THE 1998 TWENTY-THIRD INTERNATIONAL POWER MODULATOR SYMPOSIUM LA English DT Proceedings Paper CT 23rd International Power Modulator Symposium CY JUN 22-25, 1998 CL RANCHO MIRAGE, CA SP Advisory Grp Electron Devices, Army Res Lab, Army Res Off, Air Force Wright Lab, Naval Surface Warfare Ctr, Sandia Natl Labs, Univ SO CA, Electron Devices Soc IEEE AB Equations and methods for self and mutual inductance calculations of air core foil wound inductors or transformers are presented. In particular, current distribution and the related effects on inductance and coupling are analyzed and verified by experiments. The method of analysis is based on decomposing cylindrical foils into numerous loops which are characterized by self and mutual inductances. Matrix circuit analysis methods are used to solve the n-loop equations for the current distributions and to approximate simplified equivalent circuit consisting or two coupled inductors. The effects were studied using two concentric cylinders. It was found that the effects are minimal when the lengths of the cylinders are approximately the same. When the cylinders are of significantly different lengths, large eddy currents develop in the longer cylinder which significantly affect the self and mutual inductances. In all cases the method of analysis agrees with experimental data. C1 USAF, Res Lab, DEHE, Kirtland AFB, NM 87117 USA. RP O'Loughlin, JP (reprint author), USAF, Res Lab, DEHE, Phillips Site,3500 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4244-5 PY 1998 BP 233 EP 236 DI 10.1109/MODSYM.1998.741235 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BM25Z UT WOS:000078189700060 ER PT S AU Zulch, PA Goldstein, JS Guerci, JR Reed, IS AF Zulch, PA Goldstein, JS Guerci, JR Reed, IS BE Matthews, MB TI Comparison of reduced-rank signal processing techniques SO CONFERENCE RECORD OF THE THIRTY-SECOND ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS & COMPUTERS, VOLS 1 AND 2 SE CONFERENCE RECORD OF THE ASILOMAR CONFERENCE ON SIGNALS, SYSTEMS AND COMPUTERS LA English DT Proceedings Paper CT 32nd Asilomar Conference on Signals, Systems and Computers CY NOV 01-04, 1998 CL PACIFIC GROVE, CA SP Naval Postgrad Sch, Monterey, San Jose State Univ, San Jose, Monterey Bay Aquarium Res Inst, IEEE Signal Proc Soc AB This paper compares several reduced-rank signal processing algorithms for adaptive sensor array processing. The comparisons presented here use Monte Carlo analysis to evaluate the algorithmic performance as a function of both rank and sample support when the covariance matrix is unknown and estimated from collected sensor data. The adaptive techniques considered are the principal-components algorithm, the cross-spectral metric and the multistage Wiener filter. It is shown that the new multistage Wiener filtering technique provides more robust performance as a function of both rank and sample support. C1 USAF, Res Lab, SNRT, Rome, NY 13441 USA. RP Zulch, PA (reprint author), USAF, Res Lab, SNRT, 26 Elect Pkwy, Rome, NY 13441 USA. NR 14 TC 0 Z9 1 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1058-6393 BN 0-7803-5149-5 J9 CONF REC ASILOMAR C PY 1998 BP 421 EP 425 PG 5 WC Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BM43X UT WOS:000078743600078 ER PT B AU Stauffer, TB Libelo, EL MacIntyre, WG Boggs, JM Stapleton, R AF Stauffer, TB Libelo, EL MacIntyre, WG Boggs, JM Stapleton, R GP RES CTR KARLSRUHE TI A field study to quantitate important chemical and biological processes in natural attenuation SO CONTAMINATED SOIL '98, VOLS 1 AND 2 LA English DT Proceedings Paper CT 6th International FZK/TNO Conference on Contaminated Soil (ConSoil 98) CY MAY 17-21, 1998 CL EDINBURGH, SCOTLAND SP Forschungszentrum Karlsruhe, Tech & Umwelt, Netherlands Org Appl Sci Res, Scottish Enterprise, UK DE biodegradation; bioremediation; groundwater clean-up; hydrocarbons; organic contamination; natural attenuation AB In order to study the geochemical and biochemical processes which contribute to Natural Attenuation of hydrocarbons in ground water systems, a subsurface residual NAPL hydrocarbon mixture was emplaced in the heterogeneous aquifer at the Columbus AFB, MS groundwater test site. Changes in aqueous and aquifer solid geochemistry and microbiology, indicative of Natural Attenuation, are being monitored as the dissolved hydrocarbon plume is formed by groundwater flow under natural hydraulic gradients. Understanding the biogeochemisrty of the aquifer will allow a better understanding of mechanisms and rates of processes which contribute to Natural Attenuation. This, hopefully, will allow us to identify easily measured indicators Natural Attenuation, and produce a scientifically validate guides for implementation. C1 USAF, Res Lab, Tyndall AFB, FL 32403 USA. RP Stauffer, TB (reprint author), USAF, Res Lab, Tyndall AFB, FL 32403 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU THOMAS TELFORD SERVICES LTD PI LONDON PA THOMAS TELFORD HOUSE, 1 HERON QUAY, LONDON E14 4JD, ENGLAND BN 0-7277-2675-7 PY 1998 BP 95 EP 100 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BL34B UT WOS:000075208500012 ER PT S AU Wood, BE Bertrand, WT Seiber, BL Lesho, JC Uy, OM Hall, DF Dyer, JS AF Wood, BE Bertrand, WT Seiber, BL Lesho, JC Uy, OM Hall, DF Dyer, JS BE Heaney, JB Burriesci, LG TI Space environmental and contamination effects on cryogenic and warm optical surfaces - A review SO CRYOGENIC OPTICAL SYSTEMS AND INSTRUMENTS VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cryogenic Optical Systems and Instruments VIII CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE cryogenics; spacecraft; quartz crystal microbalance; QCM; TQCM; CQCM; infrared; MSX; satellite; cryofilm; infrared; telescope; contaminant; BRDF; transmittance; reflectance; germanium AB This review paper focuses on measurement techniques and facilities for the study of the contamination and space environment effects on optical and thermal radiative surfaces. Laboratory measurements are reviewed and illustrate how cryogenic and relatively warm surfaces can be affected by contaminants, vacuum, and UV. The laboratory data are used to illustrate the important parameters that require consideration when trying to determine these types of effects on future satellite missions. Optical properties of thin contaminant films, BRDF measurements on cryogenic films, quartz crystal microbalance (QCM) measurements, and UV effects on silicone/hydrocarbon films are presented and discussed relative to their applications to satellite systems. The laboratory data are complemented with flight data from the Midcourse Space Experiment (MSX) satellite. Laboratory results were used to interpret MSX spacecraft flight data. The MSX demonstration and validation satellite program was funded by the Ballistic Missile Defense Organization (BMDO). MSX had UV, visible, and infrared instruments including the Spirit 3 cryogenic telescope and had several contamination instruments for measuring pressure, gas species, water and particulate concentrations, and condensable gas species. Some of the data collected from the flight QCMs are presented. C1 Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. RP Wood, BE (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. NR 0 TC 8 Z9 8 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 0-8194-2890-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3435 BP 160 EP 171 DI 10.1117/12.323734 PG 12 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA BL84U UT WOS:000076923000017 ER PT B AU Campbell, RA AF Campbell, RA GP DECIS SCI INST DECIS SCI INST TI 'Orb'anizations - A new approach to organizational management SO DECISION SCIENCES INSTITUTE 1998 PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT 29th Annual Meeting of the Decision-Sciences-Institute CY NOV 21-24, 1998 CL LAS VEGAS, NV SP Decis Sci Inst AB Organizational contests permeate nearly every aspect of our daily lives. In fact, it is difficult to conceive of situations that are not in some way impacted by organizations, be they in working life, economics, politics, etc. No matter what the form or type, organizations seem to be sources of ambiguity, complexity, and controversy. In recent years, the literature has called us to focus on dynamic processes rather than static conceptions of organization structure. as organizations reach for viability through restructuring, new conceptual forms provide valuable ways to address various operating needs. We examine a new form and present its promise for organizations. C1 USAF Acad, Dept Management, Colorado Springs, CO 80840 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU DECISION SCIENCES INST PI ATLANTA PA UNIV PLAZA, ATLANTA, GA 30303 USA BN 0-9667118-0-7 PY 1998 BP 479 EP 481 PG 3 WC Business; Business, Finance; Psychology, Applied; Management; Operations Research & Management Science SC Business & Economics; Psychology; Operations Research & Management Science GA BN82S UT WOS:000083105000206 ER PT B AU Swartz, SM AF Swartz, SM GP DECIS SCI INST DECIS SCI INST TI The relative performance of selected heuristics on the resource constrained project scheduling problem under differing project execution strategies SO DECISION SCIENCES INSTITUTE 1998 PROCEEDINGS, VOLS 1-3 LA English DT Proceedings Paper CT 29th Annual Meeting of the Decision-Sciences-Institute CY NOV 21-24, 1998 CL LAS VEGAS, NV SP Decis Sci Inst AB The performance of scheduling heuristics for the Resource Constrained Project Scheduling Problem (RCPSP) can be affected by alternative project execution strategies. This current work seeks to expand our understanding of the relationship between planning (scheduling) and execution procedures by comparing the relative performance of a selected group of recognized scheduling heuristics on project total duration and Net Present Value (NPV) under four different execution strategies. A benchmark set of RCPSP cases were scheduled and then simulated through execution and the results are compared. The research findings indicate that relative performance is affected by the execution strategy in some cases but not in others; and that these relative standings are sensitive to the presence of variability in task duration. A new heuristic is also proposed and evaluated. C1 USAF, Inst Technol, Dept Grad Logist Management, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU DECISION SCIENCES INST PI ATLANTA PA UNIV PLAZA, ATLANTA, GA 30303 USA BN 0-9667118-0-7 PY 1998 BP 1626 EP 1628 PG 3 WC Business; Business, Finance; Psychology, Applied; Management; Operations Research & Management Science SC Business & Economics; Psychology; Operations Research & Management Science GA BN82S UT WOS:000083105000703 ER PT S AU Evwaraye, AO Smith, SR Mitchel, WC AF Evwaraye, AO Smith, SR Mitchel, WC BE Ashok, S Chevallier, J Sumino, K Sopori, BL Gotz, W TI The effect of doping on nitrogen activation energy level in 4H-SiC SO DEFECT AND IMPURITY ENGINEERED SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Defect and Impurity Engineered Semiconductors II at the Materials-Research-Society Spring Meeting CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc, Bunko Keiki, Fujitsu, Hewlett Packard Co, Hughes Res Lab, Jobin Yvon, Kodak Res Lab, Komatsu Electr Met, Mattson Technol, MEMC Electr Mat, Mitsubishi Mat Silicon, Natl Renewable Energy Lab, NEC, Nippon Steel, Photowatt, Riber, Shin Etsu Handotal, Sumitomo Sitix AB Thermal admittance spectroscopy has been used to study the thermal activation energy of nitrogen at the hexagonal and cubic sites in 4H-SiC as function of net doping concentration. The net doping concentration of the samples, which was determined from 1/C-2 vs. V plots, ranges from 1.5 x 10(14) cm(-3) to 4 x 10(18) cm(-3). The thermal activation energy of nitrogen was determined to be E - 0.054 eV and E-c - 0.101 eV for nitrogen at hexagonal and cubic sites respectively for N-D - N-A less than or equal to 10(16) cm(-3). As the free carrier concentration increases from 10(16) cm(-3) to 1.0 x 10(18) cm(-3) the thermal activation energy of nitrogen at the hexagonal site decreases from 54 meV to 24 meV. At N-D - N-A greater than or equal to 1.0 x 10(18) cm(-3) hopping conduction is the only conduction mechanism and has an activation energy of 3-9 meV. C1 USAF, Res Lab, Mat & Mfg Directorate, MLPO, Wright Patterson AFB, OH 45377 USA. RP Evwaraye, AO (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLPO, Wright Patterson AFB, OH 45377 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-416-5 J9 MATER RES SOC SYMP P PY 1998 VL 510 BP 187 EP 192 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Engineering; Materials Science GA BL88A UT WOS:000077031700026 ER PT S AU Smith, SR Evwaraye, AO Mitchel, WC AF Smith, SR Evwaraye, AO Mitchel, WC BE Ashok, S Chevallier, J Sumino, K Sopori, BL Gotz, W TI Aluminum acceptors in inequivalent sites in 4H-SiC SO DEFECT AND IMPURITY ENGINEERED SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Defect and Impurity Engineered Semiconductors II at the Materials-Research-Society Spring Meeting CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc, Bunko Keiki, Fujitsu, Hewlett Packard Co, Hughes Res Lab, Jobin Yvon, Kodak Res Lab, Komatsu Electr Met, Mattson Technol, MEMC Electr Mat, Mitsubishi Mat Silicon, Natl Renewable Energy Lab, NEC, Nippon Steel, Photowatt, Riber, Shin Etsu Handotal, Sumitomo Sitix AB P-type conductivity is normally produced in silicon carbide by doping with Al or B. The aluminum atom substitutes for silicon in the SiC lattice. Several studies have shown that nitrogen, which substitutes for carbon atoms and produces n-type conductivity in SiC, sits at the two inequivalent lattice sites in 4H-SiC, and two N activation energies of 53 meV (h) and 100 meV (kr) have been reported. Hall effect measurements and infrared absorption studies of SiC doped with Al showed only one Al activation energy, however, and the published Al activation energy in SiC (3C, 4H, and 6H) ranges from 191 meV to 280 meV. This has lead to the general conclusion that the activation energy of Al accepters in SiC does not depend on the polytype or on the lattice site occupied. Thermal Admittance Spectroscopy (TAS) has been used to determine the activation energy of Al in 4H-SiC specimens where N-A-N-D ranged fr om 7.2 x 10(15) cm(-2) to 5.6 x 10(15) cm(-2) By analogy to B in 6H-SiC, we propose two levels for Al in 4H-SiC at E-v + 0.212 eV and E-v + 0.266 eV. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Smith, SR (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 2 U1 1 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-416-5 J9 MATER RES SOC SYMP P PY 1998 VL 510 BP 193 EP 198 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Engineering; Materials Science GA BL88A UT WOS:000077031700027 ER PT S AU Vanheusden, K Warren, WL Fleetwood, DM Devine, RAB Draper, BL Schwank, JR Shaneyfelt, MR Winokur, PS AF Vanheusden, K Warren, WL Fleetwood, DM Devine, RAB Draper, BL Schwank, JR Shaneyfelt, MR Winokur, PS BE Ashok, S Chevallier, J Sumino, K Sopori, BL Gotz, W TI A nonvolatile MOSFET memory device based on mobile protons in the gate dielectric SO DEFECT AND IMPURITY ENGINEERED SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Defect and Impurity Engineered Semiconductors II at the Materials-Research-Society Spring Meeting CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Mat Res Soc, Bunko Keiki, Fujitsu, Hewlett Packard Co, Hughes Res Lab, Jobin Yvon, Kodak Res Lab, Komatsu Electr Met, Mattson Technol, MEMC Electr Mat, Mitsubishi Mat Silicon, Natl Renewable Energy Lab, NEC, Nippon Steel, Photowatt, Riber, Shin Etsu Handotal, Sumitomo Sitix AB Ever since the introduction of the metal-oxide-silicon field-effect-transistor (MOSFET), the nature of mobile and trapped charge in the oxide layer has been studied in great detail. For example, contamination with alkali ions such as sodium, causing instability of the flat-band voltage, was a major concern in the early days of MOS fabrication. Another SiO2 impurity of particular interest is hydrogen, because of its beneficial property of passivating charge traps. In this work we show that annealing of Si/SiO2/Si structures in forming gas (Ar:H-2; 95:5) above 400 degrees C can introduce mobile H+ ions into the SiO2 layer. These mobile protons are confined within the oxide layer, and their space-charge distribution is well controllable and easily rearrangeable by applying a gate bias, making them potentially useful for application in a reliable nonvolatile MOSFET memory device. We present speed, retention, endurance, and radiation tolerance data showing that this non-volatile memory technology can be competitive with existing Si-based non-volatile memory technologies such as Flash. The chemical kinetics of mobile-proton reactions in the SiO2 film are also analyzed in greater detail. Our data show that the initial buildup of mobile protons during hydrogen annealing is limited by the rate of lateral hydrogen diffusion into the buried SiO2 films. The final density of mobile protons is determined by the cooling rate which terminates the annealing process and, in the case of subsequent anneals, by the temperature of the final anneal. To explain the observations, we propose a dynamical equilibrium model. Based on these insights, the incorporation of the proton generation process into standard semiconductor process flows is discussed. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Vanheusden, K (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-416-5 J9 MATER RES SOC SYMP P PY 1998 VL 510 BP 463 EP 474 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Engineering; Materials Science GA BL88A UT WOS:000077031700066 ER PT S AU Sutherland, RL Natarajan, LV Tondiglia, VP Bunning, TJ AF Sutherland, RL Natarajan, LV Tondiglia, VP Bunning, TJ BE Luo, FC Wu, ST Kobayashi, S TI Switchable holograms for displays and other applications SO DISPLAY TECHNOLOGIES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Display Technologies II CY JUL 09-11, 1998 CL TAIPEI, TAIWAN SP SPIE Int Soc Opt Engn, SPIE Taiwan Chapter, PIDA, Natl Sci Council Taiwan DE switchable holograms; polymer-dispersed liquid crystals; displays; holographic optical elements; optical switches AB Switchable holograms exhibit an electrically controllable diffraction efficiency. Such devices form the building blocks for several applications under active consideration, including optical image and information displays. 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 these goals in a single-step photopolymer/liquid crystal composite system. We also discuss the multiple uses of this material and potential applications. 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 0 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 0-8194-2875-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3421 BP 8 EP 18 DI 10.1117/12.311048 PG 11 WC Optics SC Optics GA BM03M UT WOS:000077455400002 ER PT S AU Demirarslan, H Chan, YP Vidulich, M AF Demirarslan, H Chan, YP Vidulich, M GP NRC TI Visual information processing - Perception, decision, response triplet SO DRIVER AND VEHICLE MODELING SE TRANSPORTATION RESEARCH RECORD LA English DT Article; Proceedings Paper CT 77th Annual Meeting of the Transportation-Research-Board CY JAN, 1998 CL WASHINGTON, D.C. SP Transportat Res Board ID MINIMUM DISCRIMINATION INFORMATION; MODELS AB In performing critical tasks, the reaction time of the decision maker may mean the difference between safety and hazard. White different people have different risk-taking behavior, the process by which they react to a stimulus is fundamentally similar. The process involves perception, decision, and response. Thus, the decision maker sees an outside stimulus, processes the information and arrives at a yes or no decision, and then takes the necessary physical steps to implement the decision. For example, a driver sees the onset of a yellow light, makes up his or her mind about stopping or running for the light, and accordingly steps on the brake or the gas pedal. We refer to perception, decision, and response as the fundamental "triplet" underlying any human performance in a simple or complex environment. Unless this triplet is understood, other behavioral models cannot be constructed with confidence. By observing the percentage of drivers that run for a light and stop for a light, the authors have shown that one can separately measure the perception, decision, and response times in terms of probability distributions. The proposed approach is illustrated for drivers at an intersection through a series of experiments. Preliminary results point to its applicability toward other human tasks, such as landing an aircraft. C1 USAF, Inst Technol, Dept Operat Sci, Wright Patterson AFB, OH 45433 USA. RP Demirarslan, H (reprint author), 18 Mart Yapi Koop,A Blok 1, Canakkale, Turkey. NR 27 TC 0 Z9 0 U1 1 U2 1 PU NATL ACAD SCI PI WASHINGTON PA 2101 CONSTITUTION AVE, WASHINGTON, DC 20418 USA SN 0361-1981 BN 0-309-06503-8 J9 TRANSPORT RES REC PY 1998 IS 1631 BP 35 EP 42 PG 8 WC Computer Science, Cybernetics; Engineering, Civil; Transportation SC Computer Science; Engineering; Transportation GA BN48G UT WOS:000081984600006 ER PT J AU Channel, SR Pravecek, TL AF Channel, SR Pravecek, TL TI Metabolism of trichloroethylene in B6C3F1 mouse and human liver slices SO DRUG AND CHEMICAL TOXICOLOGY LA English DT Article ID MICE; ACID; CARCINOGENICITY; INDUCTION; RELEVANCE; RATS AB Human and B6C3F1 mouse liver tissue was exposed to trichloroethylene (TCE) to determine metabolic rate constants. Using a novel volatile exposure system based on precision-cut tissue explants, TCE biometabolism was measured by appearance of a major oxidative product trichloroacetic acid (TCA). TCE metabolic rate was linear in this system to 150 minutes, allowing calculation of Michaelis-Menten kinetic parameters, Km and Vmax. Both human and mouse liver explants tolerated exposure to TCE up to 750 mu M without evidence of cytotoxicity. Km values for mouse and human tissue were 215 and 30.6 mu M TCE, respectively, and Vmax estimates were 6.14 and 0.47 ng TCA produced per mg protein*min(-1), mouse and human, respectively. These results are consistent with other reports in describing the greater capacity of mice to metabolize TCE. Metabolic differences such as these must be considered when interpreting the implications of TCE-induced toxicity in rodent models for human health assessment. C1 USAF, Res Lab, Operat Toxicol Branch, Wright Patterson AFB, OH 45433 USA. RP Channel, SR (reprint author), 2856 G St,Area B,Bldg 79, Wright Patterson AFB, OH 45433 USA. NR 16 TC 2 Z9 2 U1 0 U2 2 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 1998 VL 21 IS 3 BP 275 EP 289 DI 10.3109/01480549809002205 PG 15 WC Chemistry, Multidisciplinary; Pharmacology & Pharmacy; Toxicology SC Chemistry; Pharmacology & Pharmacy; Toxicology GA 106FF UT WOS:000075118700003 PM 9706461 ER PT J AU Brown, P Campbell, MD Ellis, KJ Hawkes, RL Jones, J Gural, P Babcock, D Barnbaum, C Bartlett, RK Bedard, M Bedient, J Beech, M Brosch, N Clifton, S Connors, M Cooke, B Goetz, P Gaines, JK Gramer, L Gray, J Hildebrand, AR Jewell, D Jones, A Leake, M LeBlanc, AG Looper, JK McIntosh, BA Montague, T Morrow, MJ Murray, IS Nikolova, S Robichaud, J Spondor, R Talarico, J Theijsmeijer, C Tilton, B Treu, M Vachon, C Webster, AR Weryk, R Worden, SP AF Brown, P Campbell, MD Ellis, KJ Hawkes, RL Jones, J Gural, P Babcock, D Barnbaum, C Bartlett, RK Bedard, M Bedient, J Beech, M Brosch, N Clifton, S Connors, M Cooke, B Goetz, P Gaines, JK Gramer, L Gray, J Hildebrand, AR Jewell, D Jones, A Leake, M LeBlanc, AG Looper, JK McIntosh, BA Montague, T Morrow, MJ Murray, IS Nikolova, S Robichaud, J Spondor, R Talarico, J Theijsmeijer, C Tilton, B Treu, M Vachon, C Webster, AR Weryk, R Worden, SP TI Global ground-based electro-optical and radar observations of the 1999 Leonid shower: First results SO EARTH MOON AND PLANETS LA English DT Article DE Leonids 1999; meteor; meteor flux; meteor shower; meteoroids; satellite impact hazard ID METEORS; ABLATION; DANGER AB A total of 18 image intensified CCD detectors were deployed at 6 locations (two in Negev Desert, Israel, and one in each of the Canary Islands, Long Key in Florida, Haleakala in Hawaii, and the Kwajalein Atoll) to provide a real-time reporting system, as well as data for subsequent detailed analysis, for the 1999 Leonid shower. Fields of view ranged from 9 to 34 degrees, with apparent limiting stellar magnitudes from about +7 to +9. In addition, a dual frequency (29.850 and 38.15 MHz) automated meteor radar with directional determination capability was located in the Canadian Arctic at Alert, Nunavut and provided continuous monitoring of the shower from a location where the radiant was constantly above the horizon. Both the radar and electro-optical systems successfully recorded the activity of the shower in real time, and typical real-time activity plots are presented. Post-event analysis has concentrated on the Israel electro-optical wide field cameras and the time interval centered around the peak of the storm. About 2700 meteors have been digitized, with 680 measured for this analysis. Of these 371 were well enough determined to permit a single-station technique to yield approximate heights. Light curves and photometric masses were computed for these 371 Leonids which form the basis of the preliminary results reported in this paper. These cameras recorded Leonid meteors with peak luminosity in the magnitude range -3 to +5, corresponding to the photometric mass range 10(-4) to 10(-7) kg. A regression plot of photometric mass with magnitude did not indicate any change in light curve shape over the interval studied here. The peak flux as determined by the electro-optical observations was 1.6 +/- 0.1 Leonid meteors of magnitude +6.5 or brighter falling on a one square kilometer area (oriented perpendicular to the Leonid radiant) per hour. This peak flux occurred at approximately 2:07 +/-: 06 UT on Nov 18 1999, corresponding to solar longitude lambda (o) = 235.248 (epoch 2000.0). The radar results were consistent with this maximum flux rate and time. There was not a strong change in mass distribution over the few hours around maximum, although there is some indication that the peak interval was stronger in fainter meteors. Height histograms are provided for beginning, maximum luminosity and ending heights. It was found that maximum luminosity and ending heights were completely independent of mass, consistent with a dustball model in which the meteoroids are fragmented into constituent grains prior to ablation of the grains. However, the beginning height increases sharply (9.1 km per decade of photometric mass change) with increasing mass. This is possibly indicative of a volatile component which ablates early in the atmospheric trajectory. C1 Univ Western Ontario, London, ON, Canada. Ctr Commun Res, Ottawa, ON, Canada. Mt Allison Univ, Sackville, NB E0A 3C0, Canada. Sci Applicat Int Corp, Arlington, VA USA. Valdosta State Univ, Valdosta, GA USA. Pentagon, USAF, Washington, DC USA. HQ USAF Directorate Weather, Washington, DC USA. Univ Regina, Campion Coll, Regina, SK S4S 0A2, Canada. Wise Observ, Tel Aviv, Israel. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. Athabasca Univ, Athabasca, AB, Canada. USAF, HQ AFSPC DORW, Colorado Springs, CO USA. Univ Calgary, Calgary, AB, Canada. HQ USAF Space Command, Colorado Springs, CO USA. Dept Natl Def, Ottawa, ON, Canada. USAF, HQ AFSPC XPXY, Colorado Springs, CO USA. USAF, Space & Reconnaissance Requirements Div, Washington, DC 20330 USA. RP Brown, P (reprint author), Univ Western Ontario, London, ON, Canada. EM rhawkes@mta.ca RI Brosch, Noah/C-7889-2009; Gramer, Lewis/A-5620-2010 OI Gramer, Lewis/0000-0003-4772-1991 NR 28 TC 2 Z9 2 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0167-9295 J9 EARTH MOON PLANETS JI Earth Moon Planets PY 1998 VL 82-3 BP 167 EP 190 DI 10.1023/A:1017024802184 PG 24 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary SC Astronomy & Astrophysics; Geology GA 372TM UT WOS:000165250200013 ER PT J AU Linster, BG AF Linster, BG TI An evolutionary explanation for rotten kids SO ECONOMIC INQUIRY LA English DT Article AB We explore how natural selection acts upon genes for cooperation, altruism and selfishness in an prisoner's dilemma played by family members. A key parameter determining behavior is that parents and children have different expectations of future offspring. Examining asexual and sexually reproducing populations Mle show that which strategy of cooperation and defection proves be stable depends on the relative reproduction potential of the players and what proportion of the population is young. "Rotten kids" with altruistic parents can be a stable outcome where reproductive success is the goal, and natural selection may lead individuals to care about their unborn progeny. C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Linster, BG (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. EM linsterbg.dfeg@usafa.af.mil NR 21 TC 1 Z9 1 U1 1 U2 2 PU WESTERN ECONOMIC ASSOC INT PI HUNTINGTON BEACH PA 7400 CENTER AVE SUITE 109, HUNTINGTON BEACH, CA 92647-3039 USA SN 0095-2583 J9 ECON INQ JI Econ. Inq. PD JAN PY 1998 VL 36 IS 1 BP 98 EP 107 PG 10 WC Economics SC Business & Economics GA YQ093 UT WOS:000071347800009 ER PT B AU Tirenin, W AF Tirenin, W BE Khosrowpour, M TI The effectiveness of Administrative and Technical IS security countermeasures in the context of IS decentralization and connectivity: An empirical investigation in the US Federal government SO EFFECTIVE UTILIZATION AND MANAGEMENT OF EMERGING INFORMATION TECHNOLOGIES LA English DT Proceedings Paper CT Information-Resources-Management-Association International Conference CY MAY 17-20, 1998 CL BOSTON, MA SP Informat Resources Management Assoc C1 IGFA, AF Res Lab, Rome, NY 13441 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IDEA GROUP PUBLISHING PI HERSHEY PA 1331 E CHOCOLATE AVE, HERSHEY, PA 17033-1117 USA BN 1-878289-50-0 PY 1998 BP 520 EP 523 PG 4 WC Business; Business, Finance; Information Science & Library Science; Management SC Business & Economics; Information Science & Library Science GA BL88W UT WOS:000077050600066 ER PT S AU Racicot, RJ Yang, SC Brown, R AF Racicot, RJ Yang, SC Brown, R BE Reynolds, JR Jen, AKY Rubner, MF Chiang, LY Dalton, LR TI Polymeric complexes of polyaniline as anticorrosion coatings SO ELECTRICAL, OPTICAL, AND MAGNETIC PROPERTIES OF ORGANIC SOLID-STATE MATERIALS IV SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Electrical, Optical, and Magnetic Properties of Organic Solid-State Materials IV CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Int Specialty Prod, Natl Taiwan Univ, Taiwan Four Pillars, Taiwan President Enterprises, United Microelectr Corp AB During the past few years there has been a strong interest in developing conducting polymers as an alternative to the traditional anticorrosion coatings. One of the driving forces for this research comes from the need for an environmentally friendly chromate free anticorrosion coating for high strength light weight aluminum alloys. The possibilities for a new scratch-tolerant paint for steel prompted the development of conductive polymer anticorrosion paints. By molecular engineering, we have synthesized a double strand polymeric complex of polyaniline that is suitable as an anticorrosion paint on metals in low pH environments. in this article, we will discuss (1) the molecular design for solubility and adhesion, (2) the effectiveness of the electroactive coating under electrochemical impedance tests, and (3) a mechanistic study of the anticorrosion mechanism by examining the polymer/metal interfacial interactions. C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. RP Racicot, RJ (reprint author), USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-393-2 J9 MATER RES SOC SYMP P PY 1998 VL 488 BP 733 EP 740 PG 4 WC Chemistry, Applied; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Chemistry; Engineering; Materials Science; Optics GA BL06U UT WOS:000074149700106 ER PT S AU Day, PN Wang, Z Pachter, R AF Day, PN Wang, Z Pachter, R BE Reynolds, JR Jen, AKY Rubner, MF Chiang, LY Dalton, LR TI Ab initio calculations on porphyrins in the condensed phase SO ELECTRICAL, OPTICAL, AND MAGNETIC PROPERTIES OF ORGANIC SOLID-STATE MATERIALS IV SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Electrical, Optical, and Magnetic Properties of Organic Solid-State Materials IV CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Int Specialty Prod, Natl Taiwan Univ, Taiwan Four Pillars, Taiwan President Enterprises, United Microelectr Corp AB Porphyrins are a promising class of materials for optical limiting applications, and in the condensed phase solvent effects have been shown to be significant. We report results with a method designed to simulate the effects of discrete solvent molecules, namely the effective fragment potential (EFP) approach which has been implemented for use in ab initio calculations. Further, a simulated annealing (SA) method has been implemented with the EFP solvation model in an attempt to solve the problem of multiple minima in clusters of molecules. The results with this method indicate some success on models of aqueous formamide and aqueous glutamic acid. Ab initio calculations can now be carried out on porphyrins, and the solvation methods are being updated for their use on these systems. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Day, PN (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 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 1-55899-393-2 J9 MATER RES SOC SYMP P PY 1998 VL 488 BP 853 EP 858 PG 4 WC Chemistry, Applied; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Chemistry; Engineering; Materials Science; Optics GA BL06U UT WOS:000074149700126 ER PT J AU Fellner, JP Sandhu, SS AF Fellner, JP Sandhu, SS TI Diffusion-limited model for a lithium/polymer battery SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 5th International Symposium on Polymer Electrolytes (ISPE-5) CY AUG 10-16, 1996 CL UPPSALA, SWEDEN DE lithium; rechargeable; diffusion; model; diffusion coefficient; lithium manganese dioxide ID ION INSERTION CELL; ELECTRODE; CAPACITY AB A simple diffusion-limited model is presented to explain the capacity limitations of an actual 3 volt rechargeable lithium/polymer electrolyte/lithium manganese dioxide cell at low to moderate discharge rates. Chemical diffusion coefficients of lithium in lithium manganese dioxide, on the order of 10(-12)-10(-14) cm(2)/sec were determined for the temperature range of -10-40 degrees C. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 POOB, WL, Aero Prop & Power Directorate, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Dayton, OH 45469 USA. RP Fellner, JP (reprint author), POOB, WL, Aero Prop & Power Directorate, 1950 5th St,Bldg 18, Wright Patterson AFB, OH 45433 USA. NR 11 TC 0 Z9 0 U1 0 U2 5 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 1998 VL 43 IS 10-11 BP 1607 EP 1613 DI 10.1016/S0013-4686(97)10061-5 PG 7 WC Electrochemistry SC Electrochemistry GA ZT361 UT WOS:000074077400075 ER PT J AU Gambel, JM Shlim, DR Canas, LC Cox, NJ Regnery, HL Scott, RM Vaughn, DW Hoke, CH Kelley, PW AF Gambel, JM Shlim, DR Canas, LC Cox, NJ Regnery, HL Scott, RM Vaughn, DW Hoke, CH Kelley, PW TI Partnerships for detecting emerging infectious diseases: Nepal and global influenza surveillance SO EMERGING INFECTIOUS DISEASES LA English DT Letter C1 Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Washington, DC 20307 USA. CIWEC Clin, Kathmandu, Nepal. Armstrong Lab, Brooks AFB, TX 78235 USA. Ctr Dis Control & Prevent, Atlanta, GA USA. Armed Forces Res Inst Med Sci, Bangkok 10400, Thailand. RP Gambel, JM (reprint author), Walter Reed Army Med Ctr, Walter Reed Army Inst Res, Washington, DC 20307 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU CENTER DISEASE CONTROL PI ATLANTA PA ATLANTA, GA 30333 USA SN 1080-6040 J9 EMERG INFECT DIS JI Emerg. Infect. Dis PD JAN-MAR PY 1998 VL 4 IS 1 BP 128 EP 130 PG 3 WC Immunology; Infectious Diseases SC Immunology; Infectious Diseases GA YX165 UT WOS:000072012900022 PM 9452409 ER PT S AU Goeringer, ML McCabe, P Barth, SW Barnum, D AF Goeringer, ML McCabe, P Barth, SW Barnum, D BE Sisti, AF TI Distributed interactive simulation interface for intelligence data sources SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Enabling Technology for Simulation Science II CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE intelligence databases; distributed interactive simulation; protocol data unit AB Today's modeling and simulation world is rich in three-dimensional (3-D) models and distributed architectures. There is, however; a need to interject operational intelligence data into this environment. The ability to represent intelligence information in a realistically modeled environment provides a unique, exploitable, global awareness capability. We have designed and implemented the Global Awareness Visual Information System (GAVIS) Protocol Data Unit (PDU) Generator, a prototype interface that allows information in intelligence databases to be data sources for Distributed Interactive Simulation (DIS) capable systems. The interface provides tools, using middleware, to create database views and an agent to obtain database information for publication as PDUs. The current implementation provides information from sample intelligence databases for visualization in an off-the-shelf 3-D DIS viewer. C1 USAF, Res Lab, Rome, NY 13441 USA. RP Goeringer, ML (reprint author), USAF, Res Lab, Rome Res Site,32 Hangar Rd, Rome, NY 13441 USA. NR 0 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 0-8194-2818-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3369 BP 198 EP 205 DI 10.1117/12.319335 PG 8 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Information Systems; Computer Science, Software Engineering; Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BL61C UT WOS:000076007700020 ER PT J AU Jacobson, SH Sullivan, KA Johnson, AW AF Jacobson, SH Sullivan, KA Johnson, AW TI Discrete manufacturing process design optimization using computer simulation and generalized hill climbing algorithms SO ENGINEERING OPTIMIZATION LA English DT Article DE manufacturing; stochastic algorithms; hill climbing AB Discrete manufacturing process designs can be modelled using computer simulation. Determining optimal designs using such models is very difficult, due to the large number of manufacturing process sequences and associated parameter settings that exist. This has forced researchers to develop heuristic strategies to address such design problems. This paper introduces a new general heuristic strategy for discrete manufacturing process design optimization, called generalized hill climbing (GHC) algorithms. GHC algorithms provide a unifying approach for addressing such problems in particular, and intractable discrete optimization problems in general. Heuristic strategies such as simulated annealing, threshold accepting, Monte Carlo search, local search, and tabu search (among others) can all be formulated as GHC algorithms. Computational results are reported with various GHC algorithms applied to computer simulation models of discrete manufacturing process designs under study at the Materials Process Design Branch of Wright Laboratory, Wright Patterson Air Force Base (Dayton, Ohio, USA). C1 Virginia Polytech Inst & State Univ, Dept Ind & Syst Engn, Blacksburg, VA 24061 USA. USAF, Inst Technol, Grad Sch Syst & Logist, Wright Patterson AFB, OH 45433 USA. RP Jacobson, SH (reprint author), Virginia Polytech Inst & State Univ, Dept Ind & Syst Engn, Blacksburg, VA 24061 USA. OI Jacobson, Sheldon/0000-0002-9042-8750 NR 12 TC 28 Z9 28 U1 0 U2 0 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 0305-215X J9 ENG OPTIMIZ JI Eng. Optimiz. PY 1998 VL 31 IS 2 BP 247 EP 260 DI 10.1080/03052159808941372 PG 14 WC Engineering, Multidisciplinary; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 190FA UT WOS:000079950400005 ER PT J AU Lendenmann, U Spain, JC Smets, BF AF Lendenmann, U Spain, JC Smets, BF TI Simultaneous biodegradation of 2,4-dinitrotoluene and 2,6-dinitrotoluene in an aerobic fluidized-bed biofilm reactor SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID FORMER AMMUNITION PLANTS; SP STRAIN DNT; PSEUDOMONAS-SP; MICROBIAL TRANSFORMATION; 2,4,6-TRINITROTOLUENE; NITROAROMATICS; WATER; GROUNDWATER; DEGRADATION; POLLUTANTS AB Mixtures of 2,4- and 2,6-dinitrotoluene are produced in large quantities as precursors of polyurethane foams and the explosive 2,4,6-trinitrotoluene (TNT). The two isomers are widely distributed in contaminated groundwater and soil. Bacteria capable of growing with the individual isomers as the sole source of carbon, nitrogen, and energy have been isolated previously. However, attempts to degrade 2,4- and 2,6-DNT simultaneously have failed. We tested the hypothesis that a mixed culture could degrade an isomeric DNT mixture if the bacteria were grown in an aerobic biofilm at low substrate concentrations. Such conditions were achieved with a fluidized-bed biofilm reactor(FBBR). The reactor was fed aqueous solutions containing 2,4-(40 mg L(-1)) and 2,6-DNT (10 mg L(-1)). The feed flow rate was gradually increased to yield surface loading rates of 36-600 mg of DNT m(-2) d(-1). Removal efficiencies higher than 98% for 2,4-DNT and 94% for 2,6-DNT were achieved at all loading rates. The nitrogen released from DNT was found quantitatively as nitrate that indicated the presence of nitrite-oxidizing bacteria. COD measurements of the reactor effluent confirmed complete mineralization of the DNT. The results demonstrate that mixtures of 2,4- and 2,6-DNT can be biodegraded successfully in an aerobic FBBR. C1 USAF, Armstrong Lab, EQL, Tyndall AFB, FL 32403 USA. Univ Connecticut, Dept Civil & Environm Engn, Environm Engn Program, Storrs, CT 06269 USA. RP Spain, JC (reprint author), USAF, Armstrong Lab, EQL, 139 Barnes Dr, Tyndall AFB, FL 32403 USA. EM jspain@ccmail.aleq.tyndall.af.mil RI Smets, Barth/A-5076-2014 OI Smets, Barth/0000-0003-4119-6292 NR 33 TC 46 Z9 50 U1 0 U2 7 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 JAN 1 PY 1998 VL 32 IS 1 BP 82 EP 87 DI 10.1021/es970281j PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA YP503 UT WOS:000071284200034 ER PT J AU Lang, M Huang, X AF Lang, M Huang, X TI The influence of compressive loads on fatigue crack propagation in metals SO FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES LA English DT Article DE fatigue crack propagation; load interaction; residual stresses; crack closure; compression overloading; aluminum alloy ID STRESS RATIO; THRESHOLD; CLOSURE; OVERLOADS; STRENGTH; GROWTH; STEEL AB An experimental study on Al alloy 7475-T7351 was conducted to determine the influence of compressive loads on fatigue crack propagation. The investigation was based on the determination of the crack propagation stress intensity factor, K-PR, under three different basic loading sequences involving compressive loads. The data of the entire experimental program collapse onto a single 'master curve' which describes K-PR as a function of K-max and the unloading ratio UR. Load interaction effects are mainly due to the changes of the residual compressive stress state in front of the crack tip, while crack closure plays a minor part. The results give an improved understanding of fatigue crack propagation. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Beijing Inst Aeronaut Mat, Beijing 100095, Peoples R China. RP Lang, M (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 42 TC 30 Z9 31 U1 1 U2 2 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 JAN PY 1998 VL 21 IS 1 BP 65 EP 83 DI 10.1046/j.1460-2695.1998.00481.x PG 19 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA ZQ208 UT WOS:000073833600005 ER PT B AU Weaver, CL AF Weaver, CL GP AMER METEOROL SOC AMER METEOROL SOC TI USAF cognitive analysis of meteorological tasks (CAMeT) - Or - With all this high tech stuff, why aren't our forecasts getting any better? SO FIRST CONFERENCE ON ARTIFICIAL INTELLIGENCE LA English DT Proceedings Paper CT 1st Conference on Artificial Intelligence at the 78th American-Meteorological-Society Annual Meeting CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 USAF, Weather Agcy, Headquarters, Scott AFB, IL USA. RP Weaver, CL (reprint author), 102 W Losey St, Scott AFB, IL 62225 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 144 EP 145 PG 2 WC Computer Science, Artificial Intelligence; Meteorology & Atmospheric Sciences SC Computer Science; Meteorology & Atmospheric Sciences GA BL80F UT WOS:000076779400032 ER PT B AU Mandalas, GC Christ, JA Hopkins, GD McCarty, PL Goltz, MN AF Mandalas, GC Christ, JA Hopkins, GD McCarty, PL Goltz, MN BE Wickramanayake, GB Hinchee, RE TI Remediation technology transfer from full-scale demonstration to implementation: A case study of trichloroethylene bioremediation SO FIRST INTERNATIONAL CONFERENCE ON REMEDIATION OF CHLORINATED AND RECALCITRANT COMPOUNDS, VOL 1: RISK, RESOURCE, AND REGULATORY ISSUES LA English DT Proceedings Paper CT 1st International Conference on Remediation of Chlorinated and Recalcitrant Compounds CY MAY 18-21, 1998 CL MONTEREY, CA AB The fact that an innovative environmental remediation technology has been proven feasible in a full-scale evaluation does not assure that the technology will be commercialized and implemented. A number of barriers which may impede the transition of a technology from full-scale demonstration to implementation are explored. One of the most significant barriers that is within the purview of the technology developer to overcome is the requirement to properly gather and disseminate quality cost and performance data. Although a well conducted and documented field-scale technology evaluation is a generally accepted method of gathering data, the presentation and dissemination of that data is a crucial next step. An innovative method of presenting and disseminating cost and performance data using interactive software is discussed. A technology recently evaluated in a full-scale demonstration, in situ aerobic cometabolic bioremediation of trichloroethylene-contaminated groundwater through toluene injection, is presented as a case study to show how interactive software may be useful in promoting the commercialization and implementation of an innovative remediation technology. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Mandalas, GC (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-056-X PY 1998 BP 235 EP 240 PG 6 WC Chemistry, Multidisciplinary; Engineering, Environmental; Environmental Sciences; Toxicology SC Chemistry; Engineering; Environmental Sciences & Ecology; Toxicology GA BL54Q UT WOS:000075845900039 ER PT B AU Betts, PC Aurelius, M Ashburn, A Curtis, M AF Betts, PC Aurelius, M Ashburn, A Curtis, M BE Wickramanayake, GB Hinchee, RE TI Design, construction and initial operation of the source recovery system (SRS) SO FIRST INTERNATIONAL CONFERENCE ON REMEDIATION OF CHLORINATED AND RECALCITRANT COMPOUNDS, VOL 2: NONAQUEOUS-PHASE LIQUIDS LA English DT Proceedings Paper CT 1st International Conference on Remediation of Chlorinated and Recalcitrant Compounds CY MAY 18-21, 1998 CL MONTEREY, CA AB Operable Unit 2 (OU2), located at Hill Air Force Base, Utah, is a former chemical disposal pit located on the east hillside of the base, and was used from 1967 to 1975 for disposal of unknown quantities of chemicals, primarily Trichloroethylene (TCE), Tetrachloroethylene (PCE), 1,1,l-Trichloroethane (TCA) and Methylene Chloride. Because these solvents have a specific gravity greater than water, a dense non-aqueous phase liquid (DNAPL) layer settled on top of the low permeability zone beneath a shallow zone aquifer. Depth to the DNAPL is approximately 45 feet, with depth to the water table being 20 feet. A recovery system was designed and built in 1992 - 1993 with the goal of removing as much of the DNAPL as possible. The system consists of 5 extraction wells pumping a mixture of DNAPL and contaminated water into phase separation tanks. Following separation and removal of the DNAPL, the contaminated water is treated via a steam stripper, with the contaminated steam being condensed and recycled to the beginning of the process. The pretreated water is pumped to the Hill AFB Industrial Waste-water Treatment Plant (IWTP) for further processing. The system has been very effective with a total recovery of 37,000 gallons of DNAPL, and 9.5 million gallons of contaminated water treated. C1 USAF, Hill AFB, UT USA. RP Betts, PC (reprint author), USAF, Hill AFB, UT USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-057-8 PY 1998 BP 187 EP 192 PG 6 WC Engineering, Environmental; Environmental Sciences; Toxicology SC Engineering; Environmental Sciences & Ecology; Toxicology GA BL54R UT WOS:000075846000031 ER PT B AU Becvar, ESK Fisher, A Sewell, G Magar, V Gossett, J Vogel, CM AF Becvar, ESK Fisher, A Sewell, G Magar, V Gossett, J Vogel, CM BE Wickramanayake, GB Hinchee, RE TI Enhanced in situ reductive dechlorination SO FIRST INTERNATIONAL CONFERENCE ON REMEDIATION OF CHLORINATED AND RECALCITRANT COMPOUNDS, VOL 4: BIOREMEDIATION AND PHYTOREMEDIATION LA English DT Proceedings Paper CT 1st International Conference on Remediation of Chlorinated and Recalcitrant Compounds CY MAY 18-21, 1998 CL MONTEREY, CA AB Chloroethenes can be reductively dehalogenated. Hydrogen appears to be the direct electron donor. Studies with site core materials from a tetrachloroethene (PCE)-contaminated plume at Naval Air Station (NAS) Fallen, Nevada, have shown reductive dechlorination of chloroethenes to be stimulated by the addition of common fermentation products. Based on these results, a field treatability was initiated at NAS Fallen utilizing indigenous bacteria and added electron donors to promote in situ dechlorination of PCE. The field system includes injection of electron donors in various combinations in three treatment zones, isolated by barriers installed parallel to the groundwater flow path. Monitoring wells are sampled for parent compound dechlorination and dechlorination products; electron donor degradation, anaerobic fermentation products, and system stability. Transformation patterns and transport flow studies are being performed based on tracer studies, PCE removal, and the appearance of daughter products from the PCE dechlorination. After four months of operation, field monitoring of the system and laboratory analysis of collected field samples show evidence of an anaerobic environment with preliminary evidence of enhanced in situ reductive dechlorination. Continued operation of the system with nutrient injection is aimed at validating enhanced in situ reductive dechlorination as a remediation technology in a realistic field situation. C1 ARA, Tyndall AFB, FL 32403 USA. RP Becvar, ESK (reprint author), ARA, Tyndall AFB, FL 32403 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-059-4 PY 1998 BP 121 EP 127 PG 7 WC Biotechnology & Applied Microbiology; Chemistry, Multidisciplinary; Engineering, Environmental; Environmental Sciences; Microbiology; Toxicology SC Biotechnology & Applied Microbiology; Chemistry; Engineering; Environmental Sciences & Ecology; Microbiology; Toxicology GA BL54T UT WOS:000075848500020 ER PT B AU Wray, DJ McFarland, MJ AF Wray, DJ McFarland, MJ BE Wickramanayake, GB Hinchee, RE TI Metal enhanced reductive dehalogenation barrier wall design SO FIRST INTERNATIONAL CONFERENCE ON REMEDIATION OF CHLORINATED AND RECALCITRANT COMPOUNDS, VOL 6: DESIGNING AND APPLYING TREATMENT TECHNOLOGIES LA English DT Proceedings Paper CT 1st International Conference on Remediation of Chlorinated and Recalcitrant Compounds CY MAY 18-21, 1998 CL MONTEREY, CA AB Metal Enhanced Reductive Dehalogenation (MERD) is an innovative chemical process used to remediate ground water contaminated with halogenated organic compounds. MERD employs zero valent iron to catalyze the removal of the halogenated substituents from organic compounds under oxygen limited conditions. The resulting compounds are less toxic and may be rapidly mineralized by subsurface microorganisms. In the present effort, the MERD technology was evaluated for field scale application at Hill Air Force Base, Utah (Hill AFB). After consideration of site conditions, a MERD system consisting of 400 feet (121.9 m) of sheet pile funnel wall and a 20-foot (6.1 m) gate was designed and evaluated. The gate consists of three sections; a precipitation zone, the reactive iron cell, and a dispersion zone. In addition to the funnel wall and gate design, a ground water monitoring system of two-inch multi-screened wells was also incorporated into the system to evaluate the effectiveness of the MERD technology. The cost of' constructing the MERD system was estimated at $922,500 dollars. The system has a design life of 30 years and an associated operations and maintenance cost of approximately $1,278,000 dollars. C1 USAF, Ogden, UT USA. RP Wray, DJ (reprint author), USAF, Hill AFB, Ogden, UT USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-061-6 PY 1998 BP 109 EP 113 PG 5 WC Chemistry, Multidisciplinary; Engineering, Environmental; Environmental Sciences; Toxicology SC Chemistry; Engineering; Environmental Sciences & Ecology; Toxicology GA BL54V UT WOS:000075849600018 ER PT B AU Calhoun, GL McMillan, GR AF Calhoun, GL McMillan, GR GP IEEE COMP SOC TI Hands-free input devices for wearable computers SO FOURTH ANNUAL SYMPOSIUM ON HUMAN INTERACTION WITH COMPLEX SYSTEMS, PROCEEDINGS LA English DT Proceedings Paper CT 4th Annual Symposium on Human Interaction with Complex Systems (HICS 98) CY MAR 22-25, 1998 CL DAYTON, OH SP IEEE, Comp Soc, IEEE, Comp Soc Tech Comm Multimedia Comp, Lexis Nexis, USAF, Armstrong Lab, Wright State Univ, N Carolina A&T State Univ AB The advent of wearable computers marks a potential revolution in human-machine interaction and necessitates an expansion of control and display capabilities. Several emerging technologies can provide operators with a variety of new channels far interacting with weal able computers. Enabling technologies use signals from the brain, muscles, voice, Zips, head position, eye position, and gestures for the control of computers. These hands-free head-up controllers may be required to fully exploit the advantages of wearable computers. This paper describes several hands-free controllers that are candidate input devices, either individually, or as part of a multimodal interface. Controller design, task-controller mapping, and other application issues are also presented. C1 USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. RP Calhoun, GL (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-8186-8341-4 PY 1998 BP 118 EP 123 DI 10.1109/HUICS.1998.659965 PG 6 WC Computer Science, Cybernetics; Computer Science, Information Systems SC Computer Science GA BK78U UT WOS:000073380600012 ER PT B AU King, RE McNeese, MD AF King, RE McNeese, MD GP IEEE COMP SOC TI Human-computer anxiety and phobia: A consideration of foundations and interventions SO FOURTH ANNUAL SYMPOSIUM ON HUMAN INTERACTION WITH COMPLEX SYSTEMS, PROCEEDINGS LA English DT Proceedings Paper CT 4th Annual Symposium on Human Interaction with Complex Systems (HICS 98) CY MAR 22-25, 1998 CL DAYTON, OH SP IEEE, Comp Soc, IEEE, Comp Soc Tech Comm Multimedia Comp, Lexis Nexis, USAF, Armstrong Lab, Wright State Univ, N Carolina A&T State Univ AB The expectation that workers at all levels of an organization use computers is growing in many different work cultures. Many complex systems that require human interaction are heavily dependent on advanced computing support. Many problems associated with computer use have come to be classified as "human factor" breakdowns The area of computer-anxiety and computer-related fears/phobias, however, could also benefit from study and intervention. The study, of human-computer interaction has not typically addressed problems that emerge from the motivational or emotional/affective perspective. Reactions to being required to be computer literate, however, may be so extreme as to require clinical intervention. Paradoxically, potential treatments and support may be heavily reliant on emerging computing abilities. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP King, RE (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-8186-8341-4 PY 1998 BP 205 EP 208 DI 10.1109/HUICS.1998.659988 PG 4 WC Computer Science, Cybernetics; Computer Science, Information Systems SC Computer Science GA BK78U UT WOS:000073380600023 ER PT J AU Geiss, KT Bachowski, S Frazier, JM AF Geiss, KT Bachowski, S Frazier, JM TI Potential role of oxidative stress in the in vitro toxicity of 1,3-dioxolane derivatives SO FREE RADICAL BIOLOGY AND MEDICINE LA English DT Meeting Abstract C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 2 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0891-5849 J9 FREE RADICAL BIO MED JI Free Radic. Biol. Med. PY 1998 VL 25 SU 1 MA 29 BP S22 EP S22 PG 1 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 139VP UT WOS:000077051400050 ER PT B AU Blasch, E AF Blasch, E BE Arabnia, HR TI Adaptive action learning SO FUSION'98: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MULTISOURCE-MULTISENSOR INFORMATION FUSION, VOLS 1 AND 2 LA English DT Proceedings Paper CT International Conference on Multisource-Multisensor Information Fusion (FUSION 98) CY JUL 06-09, 1998 CL LAS VEGAS, NV SP Comp Sci Res, Educ & Applicat Press, Comp Vis res & applicat Tech, IEEE Signal Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm, USA Night Vis & Electr Sensors Directorate, USA Res Off, USN Off Res, Zaptron Syst Inc DE learning control; adaptive control; avoidance behavior; data association; tracking; and ATR AB For mission completion, a pilot tests the environment compares beliefs to measured data, and engages in actions that afford survival. Typically, in a rime-critical situation, a pilot is tasked to fuse measurement data to maintain track and identity updates of threatening targets. To increase the speed, robustness, and accuracy of the pilot's threat assessment an adaptive action algorithm is proposed. The adaptive action algorithm inputs mission goals, plans active measurements by reinforcing successful sequences, maintains a belief in target threats, and updates the tracking algorithm with confidence values pertaining to target measurements. The proposed adaptive action fusion is an incremental, forward-looking, threat avoidance algorithm for mission completion which reduces the search time for the simultaneous tracking and recognition of multiple targets. C1 SNAT, AFRL, Wright Patterson AFB, OH USA. RP Blasch, E (reprint author), SNAT, AFRL, Wright Patterson AFB, OH USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-02-5 PY 1998 BP 183 EP 190 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Mathematics, Applied SC Automation & Control Systems; Computer Science; Mathematics GA BR81V UT WOS:000167662000027 ER PT B AU Blasch, EP Gainey, JC AF Blasch, EP Gainey, JC BE Arabnia, HR TI Feature-based biological sensor fusion SO FUSION'98: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MULTISOURCE-MULTISENSOR INFORMATION FUSION, VOLS 1 AND 2 LA English DT Proceedings Paper CT International Conference on Multisource-Multisensor Information Fusion (FUSION 98) CY JUL 06-09, 1998 CL LAS VEGAS, NV SP Comp Sci Res, Educ & Applicat Press, Comp Vis res & applicat Tech, IEEE Signal Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm, USA Night Vis & Electr Sensors Directorate, USA Res Off, USN Off Res, Zaptron Syst Inc DE belief filtering; data association; feature-based sensor fusion; pulse-coupled neural network ID COMPUTATIONAL ARCHITECTURE; RECOGNITION; INFORMATION; NEOCORTEX; MODEL AB The paper focuses on extracting and fusing visual feature information to discern targets much like a human fuses visual, auditory, and somatosensory data. Extraction of features is performed using a Pulse Coupled Neural Network to simulate visual-cortex processing of linking related-feature information. The feature-based biological sensor fusion approach extracts features from images, associates relevant features, and uses a belief filter to confirm or deny target identity. C1 USAF, Res Lab, SNAT, WPAFB, Wright Patterson AFB, OH 45324 USA. RP Blasch, EP (reprint author), USAF, Res Lab, SNAT, WPAFB, 2241 Av Cir, Wright Patterson AFB, OH 45324 USA. NR 20 TC 1 Z9 1 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-02-5 PY 1998 BP 702 EP 709 PG 8 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Mathematics, Applied SC Automation & Control Systems; Computer Science; Mathematics GA BR81V UT WOS:000167662000101 ER PT S AU Watson, PM Weatherspoon, M Dunleavy, L Creech, GL AF Watson, PM Weatherspoon, M Dunleavy, L Creech, GL GP IEEE IEEE IEEE TI Accurate and efficient small-signal modeling of active devices using artificial neural networks SO GAAS IC SYMPOSIUM - 20TH ANNUAL, TECHNICAL DIGEST 1998 SE TECHNICAL DIGEST - IEEE GALLIUM ARSENIDE INTEGRATED CIRCUIT SYMPOSIUM LA English DT Proceedings Paper CT 20th Annual IEEE Gallium Arsenide Integrated Circuit Symposium (GaAs IC) CY NOV 01-04, 1998 CL ATLANTA, GA SP IEEE Electron Devices Soc, IEEE Microwave Theory & Tech Soc, IEEE Solid State Circuits Soc AB Artificial neural networks (ANNs) are presented for the accurate and efficient small-signal modeling of active devices. Models are developed using measured data and are valid over ranges of parameters such as frequency, bias, and ambient temperature. Once generated, these ANN models are inserted into commercial microwave circuit simulators where they can be used for computer-aided design (CAD) and optimization of microwave/mm-wave circuits. Also, the developed ANN models can give physical insight into device behavior and scaling properties when used in conjunction with an equivalent circuit approach. An advantage of the ANN modeling approach is that it provides substantial data storage reduction over previously used modeling techniques without loss of accuracy. With increased model accuracy, the potential of first-pass design success may be realized, resulting in cost savings and decreased time-to-market for new products. C1 USAF, Res Lab, Sensord Directorate, RF Components Branch, Wright Patterson AFB, OH 45433 USA. RP Watson, PM (reprint author), USAF, Res Lab, Sensord Directorate, RF Components Branch, Wright Patterson AFB, OH 45433 USA. NR 6 TC 12 Z9 12 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1064-7775 BN 0-7803-5049-9 J9 TG IEEE GAL ARS PY 1998 BP 95 EP 98 DI 10.1109/GAAS.1998.722636 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BM27D UT WOS:000078239000021 ER PT S AU Jenkins, T Kehias, L Parikh, P Ibbetson, J Mishra, U Docter, D Le, M Kiziloglu, K Grider, D Pusl, J AF Jenkins, T Kehias, L Parikh, P Ibbetson, J Mishra, U Docter, D Le, M Kiziloglu, K Grider, D Pusl, J GP IEEE IEEE IEEE TI Record power-added efficiency using GaAs on insulator MESFET technology SO GAAS IC SYMPOSIUM - 20TH ANNUAL, TECHNICAL DIGEST 1998 SE TECHNICAL DIGEST - IEEE GALLIUM ARSENIDE INTEGRATED CIRCUIT SYMPOSIUM LA English DT Proceedings Paper CT 20th Annual IEEE Gallium Arsenide Integrated Circuit Symposium (GaAs IC) CY NOV 01-04, 1998 CL ATLANTA, GA SP IEEE Electron Devices Soc, IEEE Microwave Theory & Tech Soc, IEEE Solid State Circuits Soc AB Record power-added efficiency (PAE) of 89% was obtained at 8 GHz with a gain of 9.6 dB using GaAs on insulator (GOI) MESFETs, which were operated using a 3-V supply. When the voltage was increased to 4 V, the peak PAE was 93% at 210 mW/mm with 9.2-dB gain. The ideal current-voltage characteristics with practically zero leakage current and large transconductance near pinch-off yielded PAE values approaching the theoretical limits of over-driven operation. C1 USAF, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Jenkins, T (reprint author), USAF, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1064-7775 BN 0-7803-5049-9 J9 TG IEEE GAL ARS PY 1998 BP 259 EP 262 DI 10.1109/GAAS.1998.722695 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BM27D UT WOS:000078239000056 ER PT S AU Tate, RF Anderson, BT Keating, PB Hager, GD AF Tate, RF Anderson, BT Keating, PB Hager, GD BE Dorko, EA Moler, JL TI Zeeman spectra of atomic iodine in a 0-400 Gauss B-field SO GAS AND CHEMICAL LASERS AND INTENSE BEAM APPLICATIONS 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 CY JAN 26-27, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE atomic iodine; Zeeman spectrum; hyperfine spectrum AB A high-resolution continuously tunable 1.3 mu m diode laser is used as a small signal probe to investigate the Zeeman spectra of atomic iodine. A heated quartz cell containing a small amount of I-2 is placed in a 0 to 400 gauss B field transverse to the axis of the laser probe. Hyperfine spectral scans are recorded as a function of B-field strength and laser polarization and are compared to theory with very good agreement. C1 USAF, Res Lab, PL DELC, Kirtland AFB, NM 87117 USA. RP Tate, RF (reprint author), USAF, Res Lab, PL DELC, Kirtland AFB, NM 87117 USA. NR 0 TC 5 Z9 5 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 0-8194-2707-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3268 BP 115 EP 124 DI 10.1117/12.308057 PG 10 WC Optics SC Optics GA BL12V UT WOS:000074380500014 ER PT S AU Kendrick, KR Helms, CA Quillen, B Copland, RJ AF Kendrick, KR Helms, CA Quillen, B Copland, RJ BE Dorko, EA Moler, JL TI Quantitative determination of oxygen yield in a chemical oxygen-iodine laser SO GAS AND CHEMICAL LASERS AND INTENSE BEAM APPLICATIONS 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 CY JAN 26-27, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE chemical oxygen-iodine laser; COIL; chemical laser; COIL diagnostics AB With the advent of the Airborne Laser program, the emphasis of chemical oxygen-iodine laser (COIL) research has shifted toward improving the overall efficiency. A key component of COIL is the singlet-oxygen generator (SOG). To assess the efficiency of the SOG an accurate method of determining the yield of O-2(a(1)Delta(g)), [O-2(a(1)Delta(g))]/[O-2(total)] where [O-2(total)] = [O-2(a(1)Delta(g))] + [O-2(X(3)Sigma(g)(-))], has been developed. Absorption measurements of ground-state oxygen utilizing the magnetic-dipole transition, O-2(X(3)Sigma(g)(-)) --> O-2(b(1)Sigma(g)(-)) at 763 nm, have been obtained using a diode laser in conjunction with a multiple-pass Herriot-cell on a 10 kW class supersonic COIL(RADICL). When RADICL is configured with a 0.35 " throat, 15 " diskpack, and a medium volume transition duct, with a diluent ratio (He:O-2) of 3:1, the yield of O-2(a(1)Delta(g)) in the diagnostic duct is 0.41 +/- 0.02. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Kendrick, KR (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 TC 8 Z9 8 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 0-8194-2707-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3268 BP 125 EP 129 DI 10.1117/12.308058 PG 5 WC Optics SC Optics GA BL12V UT WOS:000074380500015 ER PT S AU Latham, WP Rothenflue, JA Helms, CA Kar, A Carroll, DL AF Latham, WP Rothenflue, JA Helms, CA Kar, A Carroll, DL BE Dorko, EA Moler, JL TI Cutting performance of a Chemical Oxygen-Iodine Laser SO GAS AND CHEMICAL LASERS AND INTENSE BEAM APPLICATIONS 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 CY JAN 26-27, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers AB Chemical Oxygen-Iodine Laser (COIL) is a member of the class of high power lasers for industrial applications, including the materials processing tasks of high speed cutting and drilling. Chemical Oxygen-Iodine Laser (COIL) technology has received considerable interest over the last several years due to its short, fiber-deliverable wavelength (1.315 microns), scalability to very high powers (tens of kilowatts, cw), and demonstrated nearly diffraction-limited optical quality. its material interaction characteristics are similar to the Nd:YAG laser since the wavelengths of these lasers are comparable. This paper documents the cutting performance of a high power, good optical quality COIL. In this experiment different types of materials were cut with the COIL, and the cut depth and width are presented here as a function of various process parameters. C1 USAF, Res Lab, Dirrected Energy Directorate AFRL DE, Kirtland AFB, NM 87117 USA. RP Latham, WP (reprint author), USAF, Res Lab, Dirrected Energy Directorate AFRL DE, 3550 Aberdeen Ave,SE, Kirtland AFB, NM 87117 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 0-8194-2707-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3268 BP 130 EP 136 DI 10.1117/12.308059 PG 7 WC Optics SC Optics GA BL12V UT WOS:000074380500016 ER PT B AU Pratt, DM Chang, WS Hallinan, KP AF Pratt, DM Chang, WS Hallinan, KP BE Lee, JS TI Effects of thermocapillary stresses on the capillary limit of capillary-driven heat transfer devices SO HEAT TRANSFER 1998, VOL 5: GENERAL PAPERS LA English DT Proceedings Paper CT 11th International Heat Transfer Conference CY AUG 23-28, 1998 CL KYONGJU, SOUTH KOREA SP Korean Soc Mech Engineers ID EVAPORATING LIQUIDS; PLATES AB An investigation of thermocapillary effects on a heated and evaporating meniscus formed by a volatile liquid in a vertical capillary tube, where the evaporation is sustained by capillarity, has been carried out. This investigation is primarily experimental, although analysis is presented to gain insights into the experimental results. The work was motivated by the importance of the evaporation process from porous or grooved medium which is integral to operation of capillary-driven heat transport devices such as heat pipes and capillary pumped loops. For simple single pore capillary-driven systems it has been shown that due to energy transport, a longitudinal wall temperature gradient along a capillary pore is produced and that due to the temperature dependence of the surface tension, thermocapillary stress at the liquid-vapor interface is created. As the energy transport and thus the thermocapillary stresses increase, it has been shown that the thermocapillary effects tend to reduce the capillary pumping potential of the system and that this reduction in potential or wicking height directly effects the heat transfer characteristics of a capillary pore system. This reduction results from the dynamic effects of energy and mass transport. The dynamic effect associated with energy transport has not been considered in the predictions for the capillary limit of capillary-driven heat transfer devices in the open literature. This work therefore proposes to examine and predict the thermocapillary limit of capillary-driven heat transfer devices once energy transport is initiated. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Pratt, DM (reprint author), USAF, Res Lab, 2130 8th St,Suite 1, Wright Patterson AFB, OH 45433 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND PY 1998 BP 63 EP 67 PG 5 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA BQ70W UT WOS:000089221000011 ER PT S AU Brown, RW Franck, DL AF Brown, RW Franck, DL BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Operational utility evaluation of helmet-mounted trackers and displays (HMT/Ds) SO HELMET- AND HEAD-MOUNTED DISPLAY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet- and Head-Mounted Displays III CY APR 13-14, 1998 CL ORLANDO, FL SP SPIE AB Current Air Force aircraft, such as the F-15 and F-16, and future aircraft, have a need to leverage improving technologies such as helmet-mounted trackers and displays (HMT/Ds) to maintain superior air combat capability in future conflicts (Figure 1). HMT/Ds can allow the pilot to point weapons and to quickly slew sensors at short visual range targets in either an air-to-air or air-to-ground environment. Flight and weapons parameters commonly displayed on a head-up display (HUD) can be provided on HMT/Ds, allowing the pilot to remain "head-out" of the cockpit for longer time periods while maintaining better situational awareness. If the HMT/D systems are designed and then tested early, the results can then be used to transfer technology, and reduce risk for follow-on programs such as the Joint Helmet-Mounted Cueing System (JHMCS). This paper will address the application of early helmet-mounted systems testing by the Air Force Research Laboratory (AFRL) Helmet-Mounted Sensory Technologies (HMST) Advanced Development Program Office at Wright-Patterson AFB, OH to reduce risk and transfer technology to the JHMCS Engineering and Manufacturing Development (EMD) program. HMST is an advanced development program for developing and demonstrating enhanced helmet-mounted technologies to improve mission effectiveness and pilot situational awareness during day/night missions in all weather conditions. Through the development of advanced HMT/D technologies, pilots HMDs and NVG have traditionally been closely tied to military applications in the past. However, today Air Force laboratories are also looking for dual-use commercial applications to transfer the new technology to civilian users such as law enforcement, medical, and other commercial areas. Future HMST systems will continue to improve through the use of improved technology, design methods, and control devices such as eye tracking, 3-D audio localization, brain actuated control, and other promising experimental research. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Brown, RW (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2811-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3362 BP 110 EP 117 DI 10.1117/12.317424 PG 8 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BL61B UT WOS:000076007500012 ER PT S AU Nalepka, JP Eicher, JA AF Nalepka, JP Eicher, JA BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Operational and implementation issues for helmet-mounted displays in a real-time simulation environment SO HELMET- AND HEAD-MOUNTED DISPLAY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet- and Head-Mounted Displays III CY APR 13-14, 1998 CL ORLANDO, FL SP SPIE DE helmet-mounted display; flight simulation; field-sequential video; LAMARS AB The increasing costs of wide field-of-view visual display systems are forcing simulation facilities to investigate cheaper alternatives. One such alternative is the use of color Helmet-Mounted Displays (HMD). These relatively low cost systems provide an essentially unlimited field-of-regard, possess a fairly large binocular field-of-view, and require only two channels of computer generated imagery. A study was recently conducted at the Air Force Research Laboratory in support of the Aeronautical Systems Center's Training Systems Product Group to assess the ability of this class of HMD to provide an acceptable level of training for various mission tasks. Many operational and implementation issues were addressed during the process of developing the simulation environment. These included simulation and mission scenario software development, HMD/head-tracker integration, HMD/image-generator video interfacing, cockpit occultation mechanization, and the measurement of and compensation for system latency. This paper will focus on these issues as well as present the "lessons learned" during the course of the study. The actual results of the evaluation will be presented in a separate technical report currently being prepared by the Training Systems Product Group. C1 Air Force Res Lab, Control Integrat & Assessment Branch, VACD, Wright Patterson AFB, OH 45433 USA. RP Nalepka, JP (reprint author), Air Force Res Lab, Control Integrat & Assessment Branch, VACD, Bldg 145,Area B,2180 8th St Ste 1, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2811-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3362 BP 164 EP 173 DI 10.1117/12.317430 PG 10 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BL61B UT WOS:000076007500018 ER PT S AU Kocian, DF AF Kocian, DF BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Helmet mounted tracker and display (HMT/D) interfaces - Developing a "standardized" helmet-vehicle interface (HVI) SO HELMET- AND HEAD-MOUNTED DISPLAY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet- and Head-Mounted Displays III CY APR 13-14, 1998 CL ORLANDO, FL SP SPIE DE ATD; CRT; helmet-mounted display; HMD; helmet-mounted tracker; HMT; HMT/D; HVI; OUE; VCATS AB The successful integration of technology and human factors meets its ultimate challenge in the area of military performance. Nowhere are the stakes so high and the competition so rigorous as in the arena of combat. This paper documents the attempts to define, develop, and test a "standardized" interface for helmet-mounted tracker and displays (HMT/Ds) as these systems begin to phase into the military inventory as standard equipment for USAF and USN fighter aircraft. The design that has been evolved is based upon active use and refinement in an environment that is as close to combat conditions, as resources permit. Many of the design ideas and lessons-learned covered in this paper came either directly or indirectly from pilots and support personnel of the USAF 422 Test and Evaluation Squadron located at Nellis AFB, NV. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Kocian, DF (reprint author), USAF, Res Lab, 2255 H St,Room 300, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2811-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3362 BP 196 EP 213 DI 10.1117/12.317433 PG 18 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BL61B UT WOS:000076007500021 ER PT S AU Franck, DL Brown, RW AF Franck, DL Brown, RW BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Eye tracking equipment development for helmet mounted displays on tactical aircraft SO HELMET- AND HEAD-MOUNTED DISPLAY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet- and Head-Mounted Displays III CY APR 13-14, 1998 CL ORLANDO, FL SP SPIE DE eye trackers; helmet mounted displays AB The use of Helmet-Mounted Trackers and Displays (HMT/Ds) is becoming widespread for air-to-air, within visual range target acquisition; however these systems have physiological limitations. The Air Force Research Laboratory (AFRL) Helmet-Mounted Sensory Technologies (HMST) program is currently studying the use of eye trackers to cue High Off Boresight Angle (HOBA) missiles. The development and implementation of an eye tracker can eliminate the problems of limited head motion under high gravitational forces. This paper will discuss some of the HMST requirements needed to perform eye tracking for air-to-air targeting to complement HMT/Ds performance. This paper will also include a review of the different approaches being studied to meet those requirements. C1 USAF, Res Lab, HECV, Wright Patterson AFB, OH 45433 USA. RP Franck, DL (reprint author), USAF, Res Lab, HECV, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2811-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3362 BP 235 EP 242 DI 10.1117/12.317436 PG 8 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BL61B UT WOS:000076007500024 ER PT S AU Mead, FB Myrabo, LN Messitt, DG AF Mead, FB Myrabo, LN Messitt, DG BE Phipps, CR TI Flight experiments and evolutionary development of a laser propelled, trans-atmospheric vehicle SO HIGH-POWER LASER ABLATION, PTS 1-2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Power Laser Ablation CY APR 26-30, 1998 CL SANTA FE, NM SP SPIE, Univ Illinois, Fus Studies Lab, NE Sci & Technol Inc, Photon Associates Inc, F2 Associates Inc AB In a series of spectacular experiments conducted at the High Energy Laser Systems Test Facility (HELSTF), White Sands Missile Range (WSMR), NM, using 13- to 15-cm diameter, 40- to 60-g vehicles designed to fly on the 10 kW PLVTS pulsed carbon dioxide laser (1kJ pulses for 30 us duration at 10 Hz), Prof. Leik Myrabo of Rensselaer Polytechnic Institute (RPI) and Dr. Franklin Mead of the Air Force Research Laboratory's (AFRL) Propulsion Directorate, have been successfully flying laser propelled Lightcraft under a joint Air Force/NASA flight demonstration program. The axisymmetric Lightcraft vehicles are propelled by airbreathing, pulsed-detonation engines with an infinite fuel specific impulse. Impulse coupling coefficients have been measured with ballistic pendulums as well as a piezoelectric load cell and fall in the range of 100 to 200 N/MW. Horizontal wire-guided flights up to 400 ft,using a unique laser beam pointing and tracking guidance system, have demonstrated np to 2.0 G's acceleration measured by a photo-optic array. Spin-stabilized free-flights with active tracking/beam control have been accomplished to altitudes of 15.25 meters. This paper will summarize the progress made to date on the Lightcraft Technology Demonstration flight test program since the first 12-14 July 1996, experiments at HELSTF. C1 USAF, Res Lab, Prop Directorate, Edwards AFB, CA 93524 USA. RP Mead, FB (reprint author), USAF, Res Lab, Prop Directorate, Edwards AFB, CA 93524 USA. NR 0 TC 23 Z9 23 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 0-8194-2790-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3343 BP 560 EP 563 PG 4 WC Optics SC Optics GA BL80U UT WOS:000076793000057 ER PT S AU Telle, JM Milonni, PW Hillman, PD AF Telle, JM Milonni, PW Hillman, PD BE Basu, S TI Comparison of pump-laser characteristics for producing a mesospheric sodium guidestar for adaptive optical systems on large aperture telescopes SO HIGH-POWER LASERS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Power Lasers CY JAN 27-28, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE laser pumped mesospheric sodium guide star; beacon; adaptive optics AB We compare the effectiveness of various laser systems for producing a sodium guidestar in the mesosphere for large aperture telescopes. We discuss the requirements for two applications at two sites: satellite imaging at the Starfire Optical Range in Albuquerque, New Mexico (SI) and infrared astronomy at the Steward Observatory in Tucson, Arizona (IR). SI may use either a hybrid system employing a rayleigh and a sodium guidestar or a system employing only a sodium guidestar. IR will use only a sodium guide star. Our results are based on analysis and computation that have been compared to 5 different experiments [1]. Parameters included in our comparison are pulse format, polarization, center frequency, and bandwidth. The infrared astronomy application power requirements are low enough that state of the art laser technology can meet them. But the satellite imaging application is problematic. Required powers are sufficiently high that thermo-optic effects in materials can be a problem. C1 USAF, Res Lab, Washington, DC 20330 USA. RP Telle, JM (reprint author), USAF, Res Lab, Washington, DC 20330 USA. NR 0 TC 16 Z9 16 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 0-8194-2703-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3264 BP 37 EP 42 DI 10.1117/12.311918 PG 6 WC Optics SC Optics GA BL36K UT WOS:000075285000006 ER PT J AU De Long, HC Mitchell, JA Trulove, PC AF De Long, HC Mitchell, JA Trulove, PC TI Investigations of the electrodeposition of aluminum-manganese alloys from room temperature chloroaluminate molten salts SO HIGH TEMPERATURE MATERIAL PROCESSES LA English DT Article DE electrodeposition; molten salts; EQCM; aluminum and magnesium ID CORROSION; PHASE AB The electrochemical reduction of manganese (II) in acidic AlCl3: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-M-x in acidic AlCl3: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, Washington, DC 20332 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. RP De Long, HC (reprint author), USAF, Off Sci Res, Bolling AFB, Washington, DC 20332 USA. NR 19 TC 10 Z9 11 U1 1 U2 8 PU BEGELL HOUSE INC PI NEW YORK PA 79 MADISON AVE, SUITE 1205, NEW YORK, NY 10016-7892 USA SN 1093-3611 J9 HIGH TEMP MATER P-US JI High Temp. Mater. Process PY 1998 VL 2 IS 4 BP 507 EP 519 PG 13 WC Materials Science, Multidisciplinary SC Materials Science GA 177TA UT WOS:000079226100007 ER PT J AU Arthur, W Bennett, W Stanush, PL McNelly, TL AF Arthur, W Bennett, W Stanush, PL McNelly, TL TI Factors that influence skill decay and retention: A quantitative review and analysis SO HUMAN PERFORMANCE LA English DT Article; Proceedings Paper CT 103rd Annual Meeting of the American-Psychological-Association CY AUG 11-15, 1995 CL NEW YORK, NEW YORK SP Amer Psychol Assoc ID HUMAN-MEMORY; ACQUISITION; CONTEXT; PERFORMANCE; TASKS; MAINTENANCE; RECOGNITION; SPECIFICITY; PROSE AB This article presents a review of the skill retention and skill decay literature that focuses on factors that influence the loss of trained skills or knowledge over extended periods of nonuse. Meta-analytic techniques were applied to a total of 189 independent data points extracted from 53 articles. Results indicate that there is substantial skill loss with nonpractice or nonuse, with the amount of skill loss ranging from an effect size (d) of -0.01 immediately after training to a d of -1.4 after more than 365 days of nonuse. Most of the study's hypotheses for moderators were supported. Physical, natural, and speed-based tasks were less susceptible to skill loss than cognitive, artificial, and accuracy-based tasks. Additionally, certain methodological variables, such as using recognition tests, using similar conditions of retrieval at retention, and using behavioral evaluation criteria, resulted in less skill loss over time. Implications of the results for training and future research are discussed. C1 Texas A&M Univ, Dept Psychol, College Stn, TX 77843 USA. Armstrong Lab, HRTD, Brooks AFB, TX 78235 USA. RP Arthur, W (reprint author), Texas A&M Univ, Dept Psychol, College Stn, TX 77843 USA. EM wea@psyc.tamu.edu NR 160 TC 166 Z9 166 U1 6 U2 27 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0895-9285 J9 HUM PERFORM JI Hum. Perform. PY 1998 VL 11 IS 1 BP 57 EP 101 DI 10.1207/s15327043hup1101_3 PG 45 WC Psychology, Applied SC Psychology GA YR673 UT WOS:000071518800003 ER PT J AU Lance, CE Parisi, AG Bennett, WR Teachout, MS Harville, DL Welles, ML AF Lance, CE Parisi, AG Bennett, WR Teachout, MS Harville, DL Welles, ML TI Moderators of skill retention interval performance decrement relationships in eight US Air Force enlisted specialties SO HUMAN PERFORMANCE LA English DT Article; Proceedings Paper CT 11th Annual Conference of the Society-for-Industrial-and-Organizational-Psychology CY APR-MAY -, 1996 CL SAN DIEGO, CALIFORNIA SP Soc Ind & Org Psychol ID JOB-PERFORMANCE; INDIVIDUAL-DIFFERENCES; TRAINING PERFORMANCE; PREDICTING PILOT; ABILITY; EXPERIENCE; VALIDITY; CRITERIA; ASVAB; TASKS AB A robust finding in the literature on skill maintenance is that extended skill-retention intervals (SRIs) lead to decreased task performance. We investigated three potential moderators of the SRI/task performance decrement relationship: (a) degree of initial skill learning, (b) performer aptitude, and (c) degree of task difficulty. Results in eight samples of enlisted U.S. Air Force personnel (N = 1,544) generally supported a negative SRI/task performance relationship, hut support for moderator effects was mixed. Implications for skill maintenance in actual work settings are discussed. C1 Univ Georgia, Dept Psychol, Athens, GA 30602 USA. USAF, Res Lab, Washington, DC 20330 USA. RP Lance, CE (reprint author), Univ Georgia, Dept Psychol, Athens, GA 30602 USA. EM clance@uga.cc.uga.edu NR 70 TC 14 Z9 15 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0895-9285 J9 HUM PERFORM JI Hum. Perform. PY 1998 VL 11 IS 1 BP 103 EP 123 DI 10.1207/s15327043hup1101_4 PG 21 WC Psychology, Applied SC Psychology GA YR673 UT WOS:000071518800004 ER PT B AU McMillan, RW Currie, NC Ferris, DD Wicks, MC AF McMillan, RW Currie, NC Ferris, DD Wicks, MC BE Liao, FJ TI Concealed weapon detection using microwave and millimeter wave sensors SO ICMMT'98: 1998 INTERNATIONAL CONFERENCE ON MICROWAVE AND MILLIMETER WAVE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Microwave and Millimeter Wave Technology Proceedings CY AUG 18-20, 1998 CL BEIJING, PEOPLES R CHINA SP Chinese Inst Electr, IEEE Electr Devices Soc, IEEE Microwave Theory & Techn Soc, IEEE Antennas & Propagat Soc, IEEE Beijing Sect, IEE Beijing Ctr, Korea Inst Telemat & Electr AB Recent advances in millimeter-wave (MMW), microwave, and infrared (IR) technologies provide the means to detect concealed weapons remotely through clothing and in some cases through walls. Since the development of forward-looking infrared (FLIR) instruments, work has been ongoing in attempting to use these devices for concealed weapon detection based on temperature differences between metallic weapons and the background body temperature of the person carrying the weapon; however, the poor transmission properties of clothing in the infrared has led to the development of techniques based on lower frequencies. Focal plane arrays operating at MMW frequencies are becoming available which eliminate the need for a costly and slow mechanical scanner for generating images. These radiometric sensors also detect temperature differences between weapons and the human body background. Holographic imaging systems operating at both microwave and MMW frequencies have been developed which generate images of near photographic quality through clothing and through thin, non-metallic walls. Finally, a real-aperture radar is useful for observing people and detecting weapons through walls and in the field under reduced visibility conditions. C1 USAF, Res Lab, Sensors Directorate, Rome, NY 13441 USA. RP McMillan, RW (reprint author), USAF, Res Lab, Sensors Directorate, Rome, NY 13441 USA. NR 4 TC 2 Z9 2 U1 2 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 7-5053-5005-6 PY 1998 BP 1 EP 4 DI 10.1109/ICMMT.1998.768213 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BN17L UT WOS:000080931600001 ER PT B AU Gao, J Cao, XY AF Gao, J Cao, XY BE Liao, FJ TI Characteristics and applications of dual-gate EFT SO ICMMT'98: 1998 INTERNATIONAL CONFERENCE ON MICROWAVE AND MILLIMETER WAVE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Microwave and Millimeter Wave Technology Proceedings CY AUG 18-20, 1998 CL BEIJING, PEOPLES R CHINA SP Chinese Inst Electr, IEEE Electr Devices Soc, IEEE Microwave Theory & Techn Soc, IEEE Antennas & Propagat Soc, IEEE Beijing Sect, IEE Beijing Ctr, Korea Inst Telemat & Electr AB In this paper, Dc characteristics and working model of dual-gate FET are explained. Microwave self-oscillating mixer with stability local frequencies by the dielectric resonators is designed and developed using a dual-gate FET. A high performance date is obtained. The experimental results have shown that at s-band, the conversion gain of 5.0db, the noise figure of 9.2db and the frequency stability less than 10(-6). C1 USAF, Force Missile Inst, Shaanxi 713800, Peoples R China. RP Gao, J (reprint author), USAF, Force Missile Inst, Shaanxi 713800, Peoples R China. NR 5 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 7-5053-5005-6 PY 1998 BP 120 EP 122 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BN17L UT WOS:000080931600027 ER PT B AU Cao, XY Dai, GX Zhen, SC Gao, J AF Cao, XY Dai, GX Zhen, SC Gao, J BE Liao, FJ TI Analysis of coaxial multimode horn of two chokes SO ICMMT'98: 1998 INTERNATIONAL CONFERENCE ON MICROWAVE AND MILLIMETER WAVE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Microwave and Millimeter Wave Technology Proceedings CY AUG 18-20, 1998 CL BEIJING, PEOPLES R CHINA SP Chinese Inst Electr, IEEE Electr Devices Soc, IEEE Microwave Theory & Techn Soc, IEEE Antennas & Propagat Soc, IEEE Beijing Sect, IEE Beijing Ctr, Korea Inst Telemat & Electr AB In this paper, modes and of electromagnetic field existing in the coaxial multimode horn of two chokes are discussed and their expressions of directional pattern are given. Experimental results of coaxial multimode horn of two chokes agree with the designing value at the c-band. It is shown that the feed is not only a main lobe which is symmetrical with respect to rotation, but also a uniform phase centre of the E plane and H plane, low cross polarization and VSWR which is less than 1.4. C1 USAF, Missile Inst, Shanxi 713800, Peoples R China. RP Cao, XY (reprint author), USAF, Missile Inst, Shanxi 713800, Peoples R China. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 7-5053-5005-6 PY 1998 BP 599 EP 601 DI 10.1109/ICMMT.1998.768359 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BN17L UT WOS:000080931600145 ER PT B AU Zeng, QP AF Zeng, QP BE Liao, FJ TI Problems on demonstration of the electric field producing the magnetic field SO ICMMT'98: 1998 INTERNATIONAL CONFERENCE ON MICROWAVE AND MILLIMETER WAVE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Microwave and Millimeter Wave Technology Proceedings CY AUG 18-20, 1998 CL BEIJING, PEOPLES R CHINA SP Chinese Inst Electr, IEEE Electr Devices Soc, IEEE Microwave Theory & Techn Soc, IEEE Antennas & Propagat Soc, IEEE Beijing Sect, IEE Beijing Ctr, Korea Inst Telemat & Electr DE electric displacement; displacement current; Ampere's circuit law; induced magnetic field AB It is all known,Maxwell had extended Faraday's two expriments and reformed Ampere's circuit law to have getten a celebrated thesis of induced magnetic field produced by time varying electric field. This paper directs against the root of the formula del x H = J(D),and to point out that:1. Electric displacement doesn't exist in our space,2. Displacement current is unwarranted,3. Curlization reformation is wrong,4. Convexization reformation is of no avail,5. It is impossible that flow of electric field produces the induced magnetic field. C1 USAF, Radar Acad, Wuhan 430010, Peoples R China. RP Zeng, QP (reprint author), USAF, Radar Acad, Wuhan 430010, Peoples R China. 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 7-5053-5005-6 PY 1998 BP 602 EP 606 DI 10.1109/ICMMT.1998.768360 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA BN17L UT WOS:000080931600146 ER PT B AU Zeng, QP AF Zeng, QP BE Liao, FJ TI Problems on demonstration of the magnetic field producing the electric field SO ICMMT'98: 1998 INTERNATIONAL CONFERENCE ON MICROWAVE AND MILLIMETER WAVE TECHNOLOGY PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Microwave and Millimeter Wave Technology Proceedings CY AUG 18-20, 1998 CL BEIJING, PEOPLES R CHINA SP Chinese Inst Electr, IEEE Electr Devices Soc, IEEE Microwave Theory & Techn Soc, IEEE Antennas & Propagat Soc, IEEE Beijing Sect, IEE Beijing Ctr, Korea Inst Telemat & Electr DE Maxwell's theory; induced electric field; Lorentz's magnetic force; seen electric field AB Based on the present sicentific conclusion,this paper afresh summaries electromagnetic induction to obtain three viewpoints,that is: 1. essence of electromagnetic induction is the movement of metal electrons forced by Lorentz's force, 2. time - varying magnetic field doesn't produce electric field in free space, 3. observer doesn't see electric field while there is relative motion between the observer and the magnetic field. C1 USAF, Radar Acad, Wuhan 430010, Peoples R China. RP Zeng, QP (reprint author), USAF, Radar Acad, 117, Wuhan 430010, Peoples R China. 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 7-5053-5005-6 PY 1998 BP 607 EP 611 DI 10.1109/ICMMT.1998.768362 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA BN17L UT WOS:000080931600147 ER PT S AU Hall, CR Stiles, RJ Horwitz, CD AF Hall, CR Stiles, RJ Horwitz, CD GP IEEE COMP SOC TI Virtual reality for training: Evaluating knowledge retention SO IEEE 1998 VIRTUAL REALITY ANNUAL INTERNATIONAL SYMPOSIUM, PROCEEDINGS SE PROCEEDINGS OF THE IEEE VIRTUAL REALITY ANNUAL INTERNATIONAL SYMPOSIUM LA English DT Proceedings Paper CT IEEE 1998 Virtual Reality Annual International Symposium CY MAR 14-18, 1998 CL ATLANTA, GA SP IEEE Comp Soc, Tech Comm Comp Graph, IEEE Neural Networks Council Virtual Real Tech Comm AB Skill decay after periods of skill disuse is well known and has substantial implications when relatively long periods of time separate training from the application of learned skills. We conducted a small study that examined the differential effects of virtual reality versus conventional computer-based media on skill retention. The results reported are preliminary, but were consistent with earlier research that reports that VR may not be superior to conventional electronic media for training certain intellectual skills. Little is known, however about the effects of VR in support of practice strategies for reducing skill decay. Implications for future research are discussed. C1 USAF, Res Lab, Brooks AFB, TX 78235 USA. RP Hall, CR (reprint author), USAF, Res Lab, Brooks AFB, TX 78235 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1087-8270 BN 0-7803-4782-X J9 P IEEE VIRT REAL ANN PY 1998 BP 184 EP 189 DI 10.1109/VRAIS.1998.658488 PG 6 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Software Engineering SC Computer Science GA BK52S UT WOS:000072438600027 ER PT B AU Sandlin, BS Terzuoli, AJ AF Sandlin, BS Terzuoli, AJ GP IEEE TI Sensitivity of a genetic algorithm solution for a wire antenna geometry SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp AB The tolerance of the optimized parameters obtained using a genetic algorithm (GA) is an important consideration in the practicality of the design. Hen. the geometry of a vertical loaded monopole (VLM) is obtained using a simple GA. To understand the effect of errors in the geometry, a metric called the range improvement factor is developed, a multiplicative factor for the required distance between two quarter-wavelength monopole antennas, which is achieved by using the superior VLM design. The results of corrupting the VLM geometry with Gaussian distributed geometry errors is investigated and indicates that the original design is on a stable plateau within the solution space. C1 USAF, Inst Technol, Dayton, OH 45401 USA. RP Sandlin, BS (reprint author), USAF, Inst Technol, POB 3402, Dayton, OH 45401 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 54 EP 57 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900015 ER PT B AU Mailloux, RJ AF Mailloux, RJ GP IEEE TI Constrained feed techniques for limited field of view scanning or time delay steering SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USAF, Res Lab, Sensors Directorate, Washington, DC 20330 USA. RP Mailloux, RJ (reprint author), USAF, Res Lab, Sensors Directorate, Washington, DC 20330 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 740 EP 743 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900179 ER PT B AU Herd, J D'Angelo, J AF Herd, J D'Angelo, J GP IEEE TI Efficient modeling of complex three dimensional antenna elements in finite arrays SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. RP Herd, J (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 768 EP 771 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900186 ER PT B AU McGrath, DT AF McGrath, DT GP IEEE TI Blindness effects in ground plane-backed TEM horn arrays SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USAF, Res Lab, Kirtland AFB, NM USA. RP McGrath, DT (reprint author), USAF, Res Lab, Kirtland AFB, NM USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 1024 EP 1027 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900256 ER PT B AU Fuller, DF Terzuoli, AJ Collins, PJ Williams, R AF Fuller, DF Terzuoli, AJ Collins, PJ Williams, R GP IEEE TI 1-D feature extraction using a dispersive scattering center parametric model SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USAF, Inst Technol, Res Lab, Washington, DC 20330 USA. RP Fuller, DF (reprint author), USAF, Inst Technol, Res Lab, Washington, DC 20330 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 1296 EP 1299 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900318 ER PT B AU Wood, AW Wood, WD AF Wood, AW Wood, WD GP IEEE TI Development and numerical solution of integral equations for electromagnetic scattering from cavities SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp C1 USAF, Inst Technol, Dept Math & Stat, Wright Patterson AFB, OH 45433 USA. RP Wood, AW (reprint author), USAF, Inst Technol, Dept Math & Stat, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 2178 EP 2181 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900529 ER PT B AU Wood, WD AF Wood, WD GP IEEE TI An open-cavity RCS enhancement device for airborne applications SO IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM - ANTENNAS: GATEWAYS TO THE GLOBAL NETWORK, VOLS 1-4 SE IEEE AP-S INTERNATIONAL SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE Antennas-and-Propagation-Society International Symposium on Antennas - Gateways to the Global Network CY JUN 21-26, 1998 CL ATLANTA, GA SP IEEE, Antennas & Propagat Soc, Int Union Radio Sci, USNC, BMW Mfg Corp, Georgia Inst Technol, Georgia Tech Res Inst, Clemson Univ, Electromagnet Sci, Sci Atlanta, Spartech Associates, Millimeter Wave Technol, Wang Electro Opto Corp AB We propose an open cavity embedded in the surface of an air vehicle as a way to increase its radar cross section (RCS). The scattering from such an open cavity embedded in an infinite ground plane is calculated using a boundary integral method. The boundary integral equations are solved numerically using the Method of Moments. Numerical results are compared with measurements for a cylindrically shaped open cavity. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Wood, WD (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4478-2 J9 IEEE AP-S PY 1998 BP 2190 EP 2193 PG 4 WC Engineering, Electrical & Electronic SC Engineering GA BL38W UT WOS:000075349900532 ER PT S AU Peterson, GD AF Peterson, GD BE Smailagic, A Brodersen, R DeMan, H TI Language-based electronics systems design automation SO IEEE COMPUTER SOCIETY WORKSHOP ON VLSI '98 - SYSTEM LEVEL DESIGN, PROCEEDINGS SE IEEE Computer Society Annual on VLSI LA English DT Proceedings Paper CT IEEE-Computer-Society Workshop on VLSI 98 - System Level Design CY APR 16-17, 1998 CL ORLANDO, FL SP IEEE, Comp Soc, Tech Comm VLSI AB The ever-increasing complexity of electronic systems makes it imperative to develop effective systems level design automation languages, methodologies, and tools. Commercial systems face increasing complexity and performance requirements, while achieving decreasing times to market and maximizing profits despite shrinking product life-cycles. Defense systems face similar issues, but must also support life cycles which span years or decades, thus requiring redesign support or prevention of parts obsolescence challenges. For cost-effective development of systems in this context, design teams need to exploit the best commercial and defense design practices and adapt them as needed to also support concurrent engineering considerations. This paper explores requirements for the emerging system level design language and the methodological needs for it to support multi-disciplinary design, including hardware software co-design, mechanical and packaging support, concurrent engineering, rest, and related issues. C1 USAF, Res Lab, IFTA, Wright Patterson AFB, OH 45433 USA. RP Peterson, GD (reprint author), USAF, Res Lab, IFTA, Wright Patterson AFB, OH 45433 USA. EM petersgd@aa.wpafb.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 2159-3477 BN 0-8186-8448-8 J9 IEEE COMP SOC ANN PY 1998 BP 130 EP 135 DI 10.1109/IWV.1998.667137 PG 6 WC Computer Science, Hardware & Architecture SC Computer Science GA BK85J UT WOS:000073665500022 ER PT J AU Egan, A Ning, CZ Moloney, JV Indik, RA Wright, MW Bossert, DJ McInerney, JG AF Egan, A Ning, CZ Moloney, JV Indik, RA Wright, MW Bossert, DJ McInerney, JG TI Dynamic instabilities in master oscillator power amplifier semiconductor lasers SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article ID DIFFRACTION-LIMITED OPERATION; W CW; MOPA AB We investigate theoretically the master oscillator power amplifier using a semiconductor laser model that is fully time and space (laterally and longitudinally) resolved, We numerically examine the stability of the device and identify the nature of the different instabilities. These can arise from undamped relaxation oscillations, beating between the longitudinal modes of any of the cavities that comprise the device, or lateral filamentation. C1 Univ Arizona, Arizona Ctr Math Sci, Tucson, AZ 85721 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. USAF, Phillips Lab, Semicond Laser Branch, Kirtland AFB, NM 87117 USA. Univ Coll, Dept Phys, Cork, Ireland. RP Egan, A (reprint author), Univ Arizona, Arizona Ctr Math Sci, Tucson, AZ 85721 USA. RI Ning, C. Z./D-4699-2009 OI Ning, C. Z./0000-0003-4583-8889 NR 17 TC 46 Z9 46 U1 2 U2 4 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 JAN PY 1998 VL 34 IS 1 BP 166 EP 170 DI 10.1109/3.655020 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA YP054 UT WOS:000071236600021 ER PT S AU Stephenson, TE AF Stephenson, TE GP IEEE IEEE TI ATM over satellite for the warfighter SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB As a New World order takes shape one thing is for certain - United States military forces will be involved in armed conflicts in austere locations around the globe with minimal notice, The Joint Chiefs of Staff have recognized this and have called for an increased reliance on information technology at tactical theater, and strategic levels. Reliance an Satellite Communications will undoubtedly increase, whether on military owned or commercially leased satellites, It is my belief that traditional terrestrial (fiber) based communication schemes such as Asynchronous Transfer Mode (ATM) will be fully ported to space vehicles. C1 USAF, Falcon AFB, CO USA. RP Stephenson, TE (reprint author), USAF, Falcon AFB, CO USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 550 EP 553 PG 4 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600102 ER PT S AU Feldmann, RJ Gill, RA AF Feldmann, RJ Gill, RA GP IEEE IEEE TI Development of laser crosslink for airborne operations SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB The requirement to send ever increasing amounts of tactical military information between sensor aircraft and information processing facilities for command and control purposes has begun to press the limits of present airborne data links, even when data compression techniques are used. Utilization of optical data links is under consideration by the United States Air Force and development of a possible airborne laser data link is under way by the United States Air Force Research Laboratory Sensors Directorate (AFRL/SN). This technology development program is being conducted in two phases. The first phase included the design and evaluation of a laser data link ground demonstration carried out in August and September 1995 between a laser terminal on Mount (Mt.) Mauna Loa on the island of Hawaii and a similar laser terminal on Mt. Haleakala on the island of Maui located 150 kilometers (km) away. The laser terminals used in this ground demonstration were capable of 1.1 gigabits per second (GBPS), full duplex communications. A motion and vibration base was used to simulate an aircraft environment and the terminal instrumentation was also used to collect atmospheric effects data. Results of the ground demonstration including signal acquisition, tracking stability and scintillation were used to modify the design of the laser terminal for follow-on air-to-air operations. The second phase of the AFRL/SN development program is the transition of the ground demonstration results into a refined terminal design for installation into two business size jet aircraft. Flight demonstration of the laser data link between these two kinematic aerial platforms will be performed at distances up to 500 km. The implications these flight demonstrations will have on possible laser terminal installations in high altitude aerial platforms and the resultant ability to use advanced airborne sensors generating very large amounts of raw data in near real-time means that command, control and decision making can be made based on a more timely and thorough database of information. C1 USAF, Sensors Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Feldmann, RJ (reprint author), USAF, Sensors Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 633 EP 637 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600117 ER PT S AU Spink, B Hammond, C Williams, M Pohlmann, R AF Spink, B Hammond, C Williams, M Pohlmann, R GP IEEE IEEE TI An analysis of mitigation techniques to reduce the impact of nuisance jamming and interference on commercial satcom links supporting ATM network services SO IEEE MILITARY COMMUNICATIONS CONFERENCE - PROCEEDINGS, VOLS 1-3 SE IEEE Military Communications Conference LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 98) CY OCT 18-21, 1998 CL BOSTON, MA SP IEEE AB This paper summarizes the results of work currently being sponsored by the US Air Force Research Laboratory at Rome, New York, to identify the vulnerability of Asynchronous Transfer Mode (ATM) networks to nuisance jamming and low interference levels when operated over C and Ku band commercial satellite communications links. Mitigation techniques to reduce the effects of nuisance jamming and link interference are investigated using various coding and interleaving schemes. To assess the performance of various coding and interleaving techniques to mitigate jamming effects, a software model was built that consisted of Reed-Solomon coders and decoders, inner convolutional coders and Viterbi decoders, and block and convolutional symbol interleavers, as well as various jammer configurations. Representative nuisance jammers included broadband noise and tone jammer configurations. The model is designed so that coding and interleaving can be selectively applied to a BPSK modulated signal over a simulated SATCOM channel. Then, in response to various jamming or interference levels, optimal combinations of coding and interleaving can be determined. This is important in reducing overhead, delay and memory requirements which must be traded-off when implementing coding and interleaving techniques. In addition, an ATM header interleaver concept was developed to further improve the performance of the link at the ATM level. A modified block interleaver was used to implement the header interleaver, and performance data is given. The results of our analysis will have applicability in adaptively implementing these techniques for link optimization, and in a broader sense, it will influence how future ATM/SATCOM networks, similar to the DISN Leading Edge Services ATM/VSAT network in Bosnia, are deployed. C1 USAF, Res Lab, Rome, NY USA. RP Spink, B (reprint author), USAF, Res Lab, Rome, NY USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 2155-7578 BN 0-7803-4506-1 J9 IEEE MILIT COMMUN C PY 1998 BP 827 EP 831 PG 5 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA BL88F UT WOS:000077034600155 ER PT J AU Marciante, JR Agrawal, GP AF Marciante, JR Agrawal, GP TI Spatio-temporal characteristics of filamentation in broad-area semiconductor lasers: Experimental results SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE beam filamentation; broad-area lasers; dynamics; laser stability; optical propagation in nonlinear media; semiconductor lasers; spatio-temporal instabilities ID LINEWIDTH ENHANCEMENT FACTOR; DIFFERENTIAL GAIN; REFRACTIVE-INDEX; LATERAL-MODES; DEPENDENCE AB We experimentally study the spatial and temporal characteristics of filamentation in broad-area semiconductor lasers, Near-field measurements show that the spacing between filaments decreases as either the pumping level or the linewidth-enhancement factor is increased, Spectral measurements reveal that spatial filaments are accompanied by periodic or chaotic temporal variations, Our experimental results show excellent qualitative agreement with a theory based on a linear stability analysis of the rate equations for an infinitely wide stripe laser. C1 USAF, Res Lab, DELS, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Univ Rochester, Inst Opt, Rochester, NY 14627 USA. RP Marciante, JR (reprint author), USAF, Res Lab, DELS, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RI Agrawal, Govind/D-5380-2013 OI Agrawal, Govind/0000-0003-4486-8533 NR 14 TC 17 Z9 17 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD JAN PY 1998 VL 10 IS 1 BP 54 EP 56 DI 10.1109/68.651101 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA YN129 UT WOS:000071136000018 ER PT J AU Zahirniak, DR Sharpin, DL Fields, TW AF Zahirniak, DR Sharpin, DL Fields, TW TI A hardware-efficient, multirate, digital channelized receiver architecture SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID FREQUENCY AB An approach is presented to realizing a digital channelized receiver for signal intercept applications that provides a hardware efficient implementation of a uniform filter bank in which the number of filters K is greater than the decimation factor M. The proposed architecture allows simple channel arbitration logic to be used and provides reliable instantaneous frequency measurements, even in adjacent channel crossover regions. In the proposed implementation of the filter bank, K is related to M by K = FM where F is an integer. It is shown that the optimum selection of F allows the instantaneous frequency measurement to be made in the channel crossover region and the arbitration function to be based solely on the instantaneous frequency measurement. The development of a biter bank structure which combines the flexibility of the short-time Fourier transform (STFT) with the implementation efficiency of the polyphase filter bank decomposition, meeting these requirements and leading to a hardware-efficient implementation, is presented. C1 USAF, Wright Lab, Wright Patterson AFB, OH 45433 USA. Syst Res Lab, Dayton, OH USA. AF Inst Technol, Wright Patterson AFB, OH USA. RP Zahirniak, DR (reprint author), 3904 Stockton Loop, Albuquerque, NM 87118 USA. NR 12 TC 40 Z9 70 U1 1 U2 3 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 JAN PY 1998 VL 34 IS 1 BP 137 EP 152 DI 10.1109/7.640270 PG 16 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA YQ113 UT WOS:000071349800013 ER PT J AU Linderman, RW Kohler, RLR Linderman, MH AF Linderman, RW Kohler, RLR Linderman, MH TI A dependable high performance wafer scale architecture for embedded signal processing SO IEEE TRANSACTIONS ON COMPUTERS LA English DT Article DE computer reliability; embedded processing; wafer scale integration; parallel architectures; memory hierarchies; high-speed integrated circuits AB A high performance, programmable, floating point multiprocessor architecture has been specifically designed to exploit advanced two-and three-dimensional hybrid wafer scale packaging to achieve low size, weight, and power, and improve reliability for embedded systems applications. Processing elements comprised of a 0.8 micron CMOS dual processor chip and commercial synchronous SRAMs achieve more than 100 MFLOPS/Watt. This power efficiency allows up to 32 processing elements to be incorporated into a single 3D multichip module, eliminating multiple discrete packages and thousands of wirebonds. The dual processor chip can dynamically switch between independent processing, watchdog checking, and coprocessing modes. A fiat, SRAM memory provides predictable instruction set timing and independent and accurate performance prediction. C1 USAF, Res Lab, Rome, NY 13441 USA. RP Linderman, RW (reprint author), USAF, Res Lab, Rome, NY 13441 USA. EM lindermanr@rl.af.mil; kohlerr@rl.af.mil; lindermanm@rl.af.mil NR 12 TC 3 Z9 3 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0018-9340 J9 IEEE T COMPUT JI IEEE Trans. Comput. PD JAN PY 1998 VL 47 IS 1 BP 125 EP 128 DI 10.1109/12.656096 PG 4 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA YW177 UT WOS:000071906200011 ER PT J AU Sheu, S Liou, JJ Huang, CI AF Sheu, S Liou, JJ Huang, CI TI A new approach for SPICE simulation of AlGaAs/GaAs HBT subjected to burn-in test SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article ID HETEROJUNCTION BIPOLAR-TRANSISTORS; MODEL; BASE AB A new approach for extracting the parameters of the AlGaAs/GaAs heterojunction bipolar transistor (HBT) subjected to the electrical/thermal stress test (i.e., burn-in test) is presented. Such an approach is implemented into SPICE, thus allowing the simulations of the performance of post-burn-in HBT circuits. Steady-state, frequency, and transient responses of an HBT differential amplifier are simulated using the present HBT SPICE model. Results simulated from a two-dimensional (2-D) device simulator are also included in support of the model. C1 Univ Cent Florida, Dept Elect & Comp Engn, Orlando, FL 32816 USA. USAF, Wright Lab, Elect Device Div, Wright Patterson AFB, OH 45433 USA. RP Sheu, S (reprint author), Univ Cent Florida, Dept Elect & Comp Engn, Orlando, FL 32816 USA. NR 17 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 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD JAN PY 1998 VL 45 IS 1 BP 326 EP 329 DI 10.1109/16.658849 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA YN951 UT WOS:000071225200045 ER PT J AU Martin, CE Rogers, SK Kabrisky, M AF Martin, CE Rogers, SK Kabrisky, M TI Digital production of color Mach bands using a color human visual system model SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART A-SYSTEMS AND HUMANS LA English DT Article DE color Mach bands; human visual system models AB A model of the human color vision system is used to construct constant brightness color Mach band stimuli along two chromatic axes for display on a standard workstation color monitor. Chromatic (not brightness) Mach bands appear in the displayed stimuli as over- and under-shoots along the axis of the varied component. The stimuli me displayed on several different but similar monitors without affecting the appearance of the Mach bands. Anomalous trichromats see no change in color when presented with a stimulus containing variations along only one of the tno chromatic axes. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. Battelle Mem Inst, Cognit Syst Grp, Columbus, OH 43201 USA. RP Martin, CE (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 20 TC 1 Z9 1 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 1083-4427 J9 IEEE T SYST MAN CY A JI IEEE Trans. Syst. Man Cybern. Paart A-Syst. Hum. PD JAN PY 1998 VL 28 IS 1 BP 127 EP 130 DI 10.1109/3468.650330 PG 4 WC Computer Science, Cybernetics; Computer Science, Theory & Methods SC Computer Science GA YM436 UT WOS:000071063300013 ER PT B AU Warner, BA Misra, M AF Warner, BA Misra, M GP IEEE TI Iteratively reweighted least squares based learning SO IEEE WORLD CONGRESS ON COMPUTATIONAL INTELLIGENCE LA English DT Proceedings Paper CT 2nd IEEE World Congress on Computational Intelligence (WCCI 98) CY MAY 04-09, 1998 CL ANCHORAGE, AK SP Int Neural Network Soc, IEEE, Neural Networks Council, IEEE, Alaska Sect AB In this work we demonstrate a method to obtain maximum likelihood weight estimates for a multi-layered feed-forward neural network using least squares. The proposed method uses the Fisher's information matrix instead of the Hessian matrix to compute the search direction. Since this matrix is formulated as an inner product, it is guaranteed to be positive definite. The formulation used by the method also provides an interesting way of highlighting the multicollinearity problem in multilayered feedforward networks. C1 USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. RP Warner, BA (reprint author), USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4860-5 PY 1998 BP 1327 EP 1331 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Engineering, Biomedical; Engineering, Electrical & Electronic; Medical Informatics; Neurosciences SC Computer Science; Engineering; Medical Informatics; Neurosciences & Neurology GA BL15D UT WOS:000074493400243 ER PT B AU Cooley, TW Rosprim, D Mahan, T Thorsos, I AF Cooley, TW Rosprim, D Mahan, T Thorsos, I BE Stein, TI TI Terrain categorization from a linear etalon Hyperspectral Imager on MSTI-3 SO IGARSS '98 - 1998 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, PROCEEDINGS VOLS 1-5: SENSING AND MANAGING THE ENVIRONMENT SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT 1998 International Geoscience and Remote Sensing Symposium (IGARSS 98) on Sensing and Managing the Environment CY JUL 06-10, 1998 CL SEATTLE, WA SP IEEE, Geosci & Remote Sensing Soc, Univ Washington, NASA, NOAA, USN, Off Naval Res, Natl Space Dev Agcy Japan, Int Union Radio Sci AB The MSTI-3 satellite payload included a wedge filter Hyperspectral Imager (HSI) system. This system provided a spectral image over a small range of wavelengths from 600 to 850 nm with a relatively coarse resolution estimated to be 70m. The imaging system did not have either spectral or radiometric calibration during its orbit life cycle. Due to the orbit dawn/dusk sun synchronous equatorial crossing time, no imaging opportunities were available for vicarious calibration or validation of the sensor. This paper describes the particular challenges encountered with this type of wedge filter HSI sensor. The approach and results obtained from terrain categorization algorithms are presented for Capetown South Africa. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Cooley, TW (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4403-0 J9 INT GEOSCI REMOTE SE PY 1998 BP 171 EP 173 DI 10.1109/IGARSS.1998.702842 PG 3 WC Geosciences, Multidisciplinary; Remote Sensing SC Geology; Remote Sensing GA BL34S UT WOS:000075217100057 ER PT S AU Kessler, C Kim, J AF Kessler, C Kim, J GP SOC EXPT MECH INC SOC EXPT MECH INC TI Complex modal analysis and interpretation for rotating machinery SO IMAC - PROCEEDINGS OF THE 16TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 16th International Modal Analysis Conference (IMAC) - Model Updating and Correlation CY FEB 02-05, 1998 CL SANTA BARBARA, CA SP Soc Exptl Mech AB The use of complex variables to represent rotating vectors which describe natural modes and forced responses in rotor dynamic systems is investigated. It is shown that general planar motions and forces can be represented as the linear superposition of forward and backward rotating vectors. It is also shown that this allows frequency response functions to implicitly include directionality. Homogeneous solutions of the complex formulation lead to clear physical definitions of forward and backward modes. Substitution of general forms of response and excitation, a process analogous to that in the classical vibration problem, is shown to result in directional frequency response functions (dFRFs) which provide modal directivity and separation in the frequency domain. The paper establishes the fact that dFRFs relate the forward and backward components of the complex displacement and excitation functions. All concepts in the procedure are directly traceable to real measurable signals, which indicates that complex vibration analysis is a generalized case of classical vibration analysis of non-rotating structures. C1 USAF, Wright Lab, Wright Patterson AFB, OH 45433 USA. RP Kessler, C (reprint author), USAF, Wright Lab, WL-POOS Bldg 18A Rm 231,1950 5th St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC EXPERIMENTAL MECHANICS INC PI BETHEL PA 7 SCHOOL ST, BETHEL, CT 06801 USA SN 0277-786X BN 0-912053-59-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3243 BP 782 EP 787 PG 6 WC Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BK40H UT WOS:000072063100113 ER PT S AU Kamprath, MF Jenkin, AB AF Kamprath, MF Jenkin, AB BE Johnson, CB Maclay, TD Allahdadi, FA TI Debris collision hazard from breakups in the geosynchronous ring SO IMAGE INTENSIFIERS AND APPLICATIONS; AND CHARACTERISTICS AND CONSEQUENCES OF SPACE DEBRIS AND NEAR-EARTH OBJECTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Image Intensifiers and Applications; and Characteristics and Consequences of Space Debris and Near-Earth Objects CY JUL 23, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE debris; orbital; space; breakup; geosynchronous AB This paper presents a study of the short-term collision risk posed to the resident Earth-orbiting population by fragments generated in hypothetical explosions in the geosynchronous ring. Debris clouds resulting from such explosions contain constrictions, which are regions of high fragment density caused by the Earth's central gravitational attraction. The highest density constriction, the pinch point, is almost fixed inertially and occurs at the breakup point. Hence most of the resident geosynchronous population flies near it. In this study, the computer programs IMPACT and DEBRIS were used to assess collision risk. Program IMPACT was used to model the explosions, and program DEBRIS was used to perform short-term debris cloud propagation and compute collision risk. The four cases considered are all based on the explosion of a generic liquid apogee kick stage which has never happened in the geosynchronous ring. The satellites for which collision risk was assessed were taken from an August 1995 update of the USSPACECOM Satellite Catalog. It was found that short-term collision risk was low, even though the entire geosynchronous population flies near the pinch point. This occurs because the fragments are spread over very large volumes in geosynchronous orbit. However, approximate extrapolation of these results indicates an increased collision risk in the intermediate time frame of several months to a year. Due to the lack of a cleansing perturbation in the geostationary region, collisions are statistically likely to occur. C1 USAF, Space & Missile Ctr, Los Angeles AFB, CA 90245 USA. RP Kamprath, MF (reprint author), USAF, Space & Missile Ctr, Los Angeles AFB, CA 90245 USA. NR 15 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 0-8194-2889-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3434 BP 130 EP 139 DI 10.1117/12.331228 PG 10 WC Engineering, Aerospace; Optics; Imaging Science & Photographic Technology SC Engineering; Optics; Imaging Science & Photographic Technology GA BM32N UT WOS:000078391600014 ER PT S AU Ongstad, AP Dente, GC Tilton, ML Stohs, J Gallant, DJ AF Ongstad, AP Dente, GC Tilton, ML Stohs, J Gallant, DJ BE Choi, HK Zory, PS TI Determination of carrier lifetimes using Hakki-Paoli gain data SO IN-PLANE SEMICONDUCTOR LASERS: FROM ULTRAVIOLET TO MID-INFRARED II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on In-Plane Semiconductor Lasers - From Ultraviolet to Mid-Infrared II CY JAN 26-28, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE carrier lifetimes; Hakki-Paoli; laser gain; long-wavelength semiconductor lasers; injection efficiency AB This paper presents a technique for determining carrier lifetimes which does not require a fast detector or rely on an experimentally complex implementation. The technique is based both on a measurement and a parallel calculation: 1) A Hakki-Paoli measurement of modal gain vs. current density, g(J), and 2) A theoretical determination of the modal gain vs. carrier sheet density, g((N). Once the gain relationships have been determined, the carrier sheet density, N, can be functionally related to the current density, J, and the lifetime determined. We demonstrate this method on two InGaAs single quantum well lasers. This method may prove particularly useful for carrier lifetime estimations in long-wavelength semiconductor lasers. C1 USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RP Ongstad, AP (reprint author), USAF, Phillips Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-2723-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3284 BP 28 EP 34 DI 10.1117/12.304457 PG 7 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL04L UT WOS:000074112500004 ER PT S AU Bossert, DJ Dente, GC Tilton, ML AF Bossert, DJ Dente, GC Tilton, ML BE Choi, HK Zory, PS TI Beam quality in multi-watt semiconductor amplifiers SO IN-PLANE SEMICONDUCTOR LASERS: FROM ULTRAVIOLET TO MID-INFRARED II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on In-Plane Semiconductor Lasers - From Ultraviolet to Mid-Infrared II CY JAN 26-28, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE filamentation; semiconductor amplifiers AB Filamentation currently limits the amount of diffraction-limitied power that can be obtained from broad-area semiconductor amplifiers. This paper examines the filamentation tendencies of a wide input-aperture tapered amplifier. Experimental measurements of filament gain under varying duty-cycle are offered and compared to theory. A numerical simulation of the device operation, which addresses non-uniform current injection, is also presented. C1 USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RP Bossert, DJ (reprint author), USAF, Phillips Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-2723-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3284 BP 63 EP 71 DI 10.1117/12.304432 PG 9 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL04L UT WOS:000074112500008 ER PT S AU McDaniel, DL Moeller, C Falcon, M Murry, SJ Lin, CH Yang, RQ Pei, SS Gianardi, DM Yan, C Ongstad, A AF McDaniel, DL Moeller, C Falcon, M Murry, SJ Lin, CH Yang, RQ Pei, SS Gianardi, DM Yan, C Ongstad, A BE Choi, HK Zory, PS TI High-power optically pumped type-II quantum-well lasers SO IN-PLANE SEMICONDUCTOR LASERS: FROM ULTRAVIOLET TO MID-INFRARED II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on In-Plane Semiconductor Lasers - From Ultraviolet to Mid-Infrared II CY JAN 26-28, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE semiconductor laser infrared; type-II quantum well; optical pumping; power efficiency; diode pumping AB Stimulated emission in InAs/InGaSb/InAs/AlSb type-II quantum-well (QW) lasers was observed up to room temperature at 4.5 mu m, optically pumped by a pulsed 2-mu m Tm:YAG laser. The absorbed threshold peak pump intensity was only 1.1 kW/cm(2) at 300 K, with a characteristic temperature T-0 of 61.6 K for temperatures up to 300 K We have also studied another type-II QW laser using 0.808-mu m pumping sources with a much longer pulse length of 50 mu s. The devices demonstrated a maximum output power of 1.6 W per facet at 83 K, with a corresponding differential external quantum efficiency of 24.8%. C1 USAF, Res Lab, Semicond Laser Branch, Kirtland AFB, NM 87117 USA. RP McDaniel, DL (reprint author), USAF, Res Lab, Semicond Laser Branch, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-2723-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3284 BP 285 EP 293 PG 9 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL04L UT WOS:000074112500032 ER PT S AU Biggers, R Varanasi, C Maartense, I Dempsey, D Mast, D Liptak, D Jones, J Peterson, TL Murray, T Busbee, J AF Biggers, R Varanasi, C Maartense, I Dempsey, D Mast, D Liptak, D Jones, J Peterson, TL Murray, T Busbee, J BE Rosenthal, PA Duncan, WM Woollam, JA TI Spectral-component monitoring of the plumes generated during the deposition of RE(Y,Nd) Ba2Cu3O7-x films by pulsed laser ablation SO IN SITU PROCESS DIAGNOSTICS AND INTELLIGENT MATERIALS PROCESSING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium In Situ Process Diagnostics and Intelligent Materials Processing CY DEC 02-05, 1997 CL BOSTON, MA SP Mat Res Soc (MRS) AB YBa2Cu3O7-x (Y123) and NdBa2Cu3O7-x (Nd123) thin films were deposited by PLD using a 248 nm wavelength KrF excimer laser. The emission spectra PLD process control techniques developed to grow reproducibly high quality Y123 thin films were also applied to the Nd123 depositions. The time-resolved spectral components of plumes generated from Y123 and Nd123 targets at the same deposition conditions were compared. When the two targets were mounted at the same distance from the substrate heater, the spectral emissions at 327 +/- 5 nm (Cu*) were essentially identical for similar laser pulse energies and other deposition conditions (150 mTorr oxygen pressure, 760 degrees C substrate heater temperatures, etc.). High quality Nd123 films (Tc similar to 93 K, Jc > 2x10(6) A/cm(2)) are considerably more difficult to produce than those of Y123. Deposition conditions associated with PLD of high quality Y123 films produce very poor Nd123 films. This observation is consistent with the belief that the nucleation and growth of Nd123 are significantly different than that of Y123. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Biggers, R (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 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 1-55899-407-6 J9 MATER RES SOC SYMP P PY 1998 VL 502 BP 215 EP 219 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Engineering; Materials Science GA BL42U UT WOS:000075472800030 ER PT S AU Hopkins, M Henderson, D Moses, R Ryall, T Zimcik, D Spangler, R AF Hopkins, M Henderson, D Moses, R Ryall, T Zimcik, D Spangler, R BE Sater, JM TI Active vibration suppression systems applied to twin tail buffeting SO INDUSTRIAL AND COMMERCIAL APPLICATIONS OF SMART STRUCTURES TECHNOLOGIES - SMART STRUCTURES AND MATERIALS 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Smart Structures and Materials 1998 - Industrial and Commercial Applications of Smart Structures Technologies CY MAR 03-05, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers, Soc Exptl Mech Inc, Amer Soc Mech Engineers, BF Goodrich Aerosp, USAF Res Lab, Def Adv Res Projects Agcy, Ceram Soc Japan, Intelligent Mat Forum, Japan, USA Res Off DE vibration; buffet; aircraft; piezoelectric; active control AB Buffeting is an aeroelastic phenomenon that plagues high performance aircraft, especially those with twin vertical tails. Unsteady vortices emanate from wing/fuselage leading edge extensions when these aircraft maneuver at high angles of attack. These aircraft are designed such that the vortices shed while maneuvering at high angles of attack and improve the lift-to-drag ratio of the aircraft. With proper placement and sizing of the vertical tails, this improvement may be maintained without adverse effects to the tails. However, there are tail locations and angles of attack where these vortices burst and immerse the vertical tails in their wake inducing severe structural vibrations. The resulting buffet loads and severe vertical tail response became an airframe life and maintenance concern as life cycle costs increased. Several passive methods have been investigated to reduce the buffeting of these vertical tails with limited success. As demonstrated through analyses, wind-tunnel investigations, and full-scale ground tests, active control systems offer a promising solution to alleviate buffet induced strain and increase the fatigue life of vertical tails. A collaborative research project including the United States, Canada, and Australia is in place to demonstrate active buffet load alleviation systems on military aircraft. The present paper provides;details on this collaborative project and other research efforts to reduce the buffeting response of vertical tails in fighter aircraft. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Hopkins, M (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 10 Z9 10 U1 1 U2 6 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2770-5 J9 P SOC PHOTO-OPT INS PY 1998 VL 3326 BP 27 EP 33 DI 10.1117/12.310663 PG 7 WC Engineering, Aerospace; Engineering, Mechanical; Optics; Transportation SC Engineering; Optics; Transportation GA BL31K UT WOS:000075067700003 ER PT S AU Fridrich, J Baldoza, AC Simard, RJ AF Fridrich, J Baldoza, AC Simard, RJ BE Aucsmith, D TI Robust digital watermarking based on key-dependent basis functions SO INFORMATION HIDING SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 2nd International Workshop on Information Hiding CY APR 14-17, 1998 CL PORTLAND, OREGON DE robust image watermarking; attacks; orthogonal patterns; secure public watermark detector AB In this paper, we introduce the concept of key-dependent basis functions and discuss its applications to secure robust watermarking for copyright protection and to designing secure public black-box watermark detectors. The new schemes overcome a possible security weakness of global, non-adaptive schemes that apply watermark patterns spanned by a small number of publicly known basis functions. The watermark is embedded into the projections of an image onto the secret set of key-dependent functions (patterns). The robustness of the watermarking scheme with respect to filtering, lossy compression, and combinations of many other attacks is studied. Finally, we propose a candidate for a watermarking scheme that enables the construction of a secure public watermark detector. C1 SUNY Binghamton, Ctr Intelligent Syst, Binghamton, NY 13902 USA. USAF, Res Lab, IFEC, Rome, NY 13441 USA. RP Fridrich, J (reprint author), SUNY Binghamton, Ctr Intelligent Syst, Binghamton, NY 13902 USA. NR 18 TC 17 Z9 17 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65386-4 J9 LECT NOTES COMPUT SC PY 1998 VL 1525 BP 143 EP 157 PG 15 WC Computer Science, Theory & Methods SC Computer Science GA BP55H UT WOS:000085483300011 ER PT S AU Brown, GJ Ahoujja, M Szmulowicz, F Mitchel, WC Lin, CH AF Brown, GJ Ahoujja, M Szmulowicz, F Mitchel, WC Lin, CH BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Mid-IR photodetectors based on InAs/InGaSb type-II quantum wells SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB We report on the growth and characterization of InAs/InxGa1-xSb strained-layer superlattices (SLS) designed with a photoresponse cut-off wavelength of 10 mu m. The structural parameters, layer thicknesses and compositions, were chosen to optimize the infrared absorption for a superlattice with an energy band gap of 120 meV. The energy band structure and optimized absorption coefficient were determined with an 8x8 envelope function approximation model. The superlattices were grown by molecular beam epitaxy and were comprised of 100 periods of 43.6 Angstrom InAs and 17.2 Angstrom In.23Ga.77Sb lattice-matched to the GaSb substrates. In order to reduce the background carrier concentrations in this material, superlattices grown with different substrate temperatures were compared before and after annealing. This set of superlattice materials was characterized using x-ray diffraction, photoresponse and Hall measurements. The measured photoresponse cut-off energies of 116 +/- 6 meV is in good agreement with the predicted energy band gap for the superlattice as designed. The intensity of the measured mid-infrared photoresponse was found to improve by an order of magnitude for the superlattice grown at the lower substrate temperature and then annealed at 520 degrees C for 10 minutes. However, the x-ray diffraction spectra were very similar before and after annealing. The temperature dependent Hall measurements at tow temperatures (<25K) were dominated by holes with quasi two-dimensional behavior. An admirably low background carrier concentration of 1x10(12) cm(-2) was measured at low temperature. C1 USAF, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Brown, GJ (reprint author), USAF, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 9 Z9 9 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 129 EP 134 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400018 ER PT S AU Brown, GJ Ohmer, MC Schunemann, PG AF Brown, GJ Ohmer, MC Schunemann, PG BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Photoresponse studies of the polarization dependence of the CdGeAs2 band edge SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB Mid-infrared photoresponse studies were performed on an oriented p-type cadmium germanium arsenide uniaxial crystal. The effects of optical polarization alignment, parallel and perpendicular to the c-axis of the crystal, were studied, as well as the effects of the transport electric-field direction. The measured optical band edge was 0.578 eV at 10 K for all polarization and bias configurations. This band gap energy is in good agreement with absorption and photoluminescence results for this sample. However, the photoresponse spectrum measured with unpolarized light at 10 K showed a much lower onset at 0.50 eV. This difference in the low temperature activation energy of the photoresponse is attributed to deep native defect levels near the band edge. These deep levels at times obscure the true band edge and can cause under estimates of the band gap energy. These results can explain the wide disparity in the reported CdGeAs2 band gap in the literature. In addition, the intensity of the photoresponse was found to be only slightly dependent on the optical polarization direction, but strongly dependent on the bias electric-field direction. The largest photoreponse was observed when the optical polarization was parallel to the c-axis and the bias electric field was perpendicular to the c-axis. The bias electric-field direction also had a significant effect upon the temperature dependence of the peak photoresponse intensity. The temperature dependence of the CdGeAs2 energy band gap was determined by empirical fitting. C1 MLPO, AFRL, Mat & Mfg Directorate, AF Res Lab, Wright Patterson AFB, OH 45433 USA. RP Brown, GJ (reprint author), MLPO, AFRL, Mat & Mfg Directorate, AF Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 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 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 531 EP 536 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400074 ER PT S AU Zelmon, DE Small, DL Schunemann, P AF Zelmon, DE Small, DL Schunemann, P BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Refractive index measurements of barium titanate from .4 to 5.0 microns and implications for periodically poled frequency conversion devices SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB Barium titanate has recently been suggested as a possible candidate for use in periodically poled optical frequency conversion devices. We report refractive index measurements which are critical to periodically poled device designers and present quasi phase matching loci which can be used to design an optical parametric oscillator in periodically poled barium titanate. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Zelmon, DE (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 537 EP 541 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400075 ER PT S AU Fernelius, NC Hopkins, FK Singh, NB Suhre, D Marable, M Hopkins, RH Meyer, R Mui, P AF Fernelius, NC Hopkins, FK Singh, NB Suhre, D Marable, M Hopkins, RH Meyer, R Mui, P BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Operational characteristics of GaSe crystals for mid-IR and far-IR applications SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB GaSe has a number of attractive properties for nonlinear optical applications including large birefringence for ease in phase matching. Its biggest drawback is its mechanical properties. GaSe has a strong tendency to cleave along the < 100 > plane which has made it difficult to grow and fabricate. We have developed a method to modify GaSe by structurally strengthening the material by doping. We have synthesized large boules of GaSe reacted mixtures and grown centimeter size single crystals by the Bridgman technique. Depending on the dopant and crystal quality, SHG measurements indicate a d(eff) of 51 to 76 pm/V. SHG power levels were theoretically calculated and appear to be in good agreement with the experimental data. The measured performance of crystals for the fourth harmonic generation and laser damage threshold are also reported in this paper. The damage threshold was greater than 2.8 J/cm(2) and 85 KW/cm(2) at the surface of the crystal. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Fernelius, NC (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 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 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 567 EP 571 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400080 ER PT S AU Ohmer, MVC Guha, S Perrin, RE Rea, LS Yu, PW Fathimulla, A AF Ohmer, MVC Guha, S Perrin, RE Rea, LS Yu, PW Fathimulla, A BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Frequency doubling of CW and pulsed CO2 lasers using diffusion-bonded, quasi-phase-matched GaAs stacks SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB We describe the fabrication, characterization and frequency doubling properties of first order stacks of diffusion bonded 2 " diameter GaAs wafers. Near IR imaging through the stacks indicated that excellent bonding was obtained over 40%-70% of the central area of the wafers. A power spectrum analysis of the spectral noise (due to interface reflections) appearing in the transmission data is shown to be a quantitative diagnostic tool useful for determining interface quality and for accurately estimating the thickness of the bonded layers in a stack. The conversion efficiency for a four layer stack at 10.6 microns was found to be 0.03% or 3 mi for a 10 mi pulse with a 100 nanosecond pulse length. The corresponding efficiency for cw SHG was found to be 0.0002%. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Ohmer, MVC (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 573 EP 580 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400081 ER PT S AU Smith, SR Evwaraye, AO Ohmer, MC AF Smith, SR Evwaraye, AO Ohmer, MC BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Characterization of CdGeAs2 using capacitance methods SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB Thermal Admittance Spectroscopy(TAS) has been used to detect energy levels in the bandgap of CdGeAs2 specimens. Capacitance-Voltage(CV) measurements were used to determine the net free carrier concentration of the specimens as well as the conductivity type. All specimens were found to be p-type. CV measurements determined that the free carrier densities ranged from 1.2 x 10(17) cm(-3) to 8 x 10(18) cm(-3). Usually one peak (but in some cases two) was observed in the thermal admittance spectra. One peak present in two samples indicates an acceptor with a thermal activation energy of E-v+(0.10-0.13) eV which corresponds closely to the value of 0.10-0.12 eV found from Hall effect measurements on these specimens. The additional peak observed could correspond to a second deeper acceptor at E-v+0.346 eV, however, the energy could not be accurately determined because the peak was not fully resolved. Evidence for the existence of two native accepters from electron paramagnetic resonance has recently been reported which tends to support a two acceptor model. C1 USAF, Res Lab, Mat & Mfg Directorate, MLPO, Wright Patterson AFB, OH 45377 USA. RP Smith, SR (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLPO, Wright Patterson AFB, OH 45377 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 581 EP 585 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400082 ER PT S AU Manasreh, MO Chavez, JR Kemp, WT Hoenshel, K Missous, M AF Manasreh, MO Chavez, JR Kemp, WT Hoenshel, K Missous, M BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI gamma-Ray irradiation effect on the intersubband transition in InGaAs/AlGaAs multiple quantum wells SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB Intersubband transitions in n-type InGaAs/AlGaAs multiple quantum wells were studied as a function of 1.0 to 5.0 MRad gamma-ray irradiation dose using the optical absorption technique. The spectra were recorded at both 295 and 77X. The results show that the total integrated area of the intersubband transition is decreased as the irradiation dose is increased. This could be explained as follows: The secondary electrons generated from the gamma-ray irradiation cause lattice damages where traps and point defects are created. Some of the electrons in the quantum wells are trapped by these defects causing the two dimensional electron gas (2DEG) density to decrease. The reduction of the 2DEG density thus leads to the reduction of the total integrated area of the intersubband transitions. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Manasreh, MO (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 637 EP 641 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400091 ER PT S AU Nathan, V AF Nathan, V BE McDaniel, DL Manasreh, MO Miles, RH Sivananthan, S TI Optical absorption in Hg1-xCdxTe SO INFRARED APPLICATIONS OF SEMICONDUCTORS II SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Infrared Applications of Semiconductors II, at the 1997 MRS Fall Meeting CY DEC 01-04, 1997 CL BOSTON, MA SP Mat Res Soc, USAF Off Sci Res, USAF Res Lab, Semiconductor Laser Branch, USAF Res Lab, Space Sensing & Vehicle Control Branch AB The theory of optical absorption due to interband transitions in direct-gap semiconductors is revisited. A new analytical expression for linear absorption coefficient in narrow-gap semiconductors is obtained by including the nonparabolic band structure due to Keldysh and Burstein-Moss shift. Numerical results are obtained for Hg1-xCdxTe for several values of x and temperature, and compared with recent experimental data. The agreement is found to be good. C1 USAF, Res Lab, VSSS, Kirtland AFB, NM 87117 USA. RP Nathan, V (reprint author), USAF, Res Lab, VSSS, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-389-4 J9 MATER RES SOC SYMP P PY 1998 VL 484 BP 667 EP 671 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98L UT WOS:000073983400096 ER PT S AU Nicholson, RA Mead, KD AF Nicholson, RA Mead, KD BE Dereniak, EL Sampson, RE TI Complete characterization of advanced focal plane arrays at the Arnold Engineering Development Center SO INFRARED DETECTORS AND FOCAL PLANE ARRAYS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Detectors and Focal Plane Arrays V CY APR 14-17, 1998 CL ORLANDO, FL SP SPIE DE focal plane array; radiometric calibration; mission simulation; crosstalk; parametric characterization; testing AB The Arnold Engineering Development Center (AEDC) has been involved in the characterization of infrared detector and focal plane arrays (FPAs) since 1986. Test facilities have been developed to allow all aspects of FPA performance and operation to be evaluated. Basic radiometric characterization can be performed in several low background chambers, and a scene generation system has been developed and implemented to allow complex scenes to be projected and evaluated. The facilities have been continuously upgraded to accommodate testing of increasingly larger and more complex arrays. Special analysis tools have been developed to allow processing of the large quantity of data acquired for the arrays. C1 Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. RP Nicholson, RA (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. NR 0 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 0-8194-2828-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3379 BP 498 EP 509 DI 10.1117/12.317619 PG 12 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics; Imaging Science & Photographic Technology SC Engineering; Remote Sensing; Optics; Imaging Science & Photographic Technology GA BL57H UT WOS:000075913800049 ER PT S AU McCarley, PL Massie, MA Baxter, CR Huynh, BL AF McCarley, PL Massie, MA Baxter, CR Huynh, BL BE Pain, B Lomheim, TS TI NeuroSeek dual-color image processing infrared focal plane array SO INFRARED READOUT ELECTRONICS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Infrared Readout Electronics IV CY APR 13, 1998 CL ORLANDO, FL SP SPIE DE infrared; focal plane array; dual color; smart FPA; neuromorphic; sensor fusion AB Several technologies have been developed in recent years to advance the state of the art of infrared sensor systems including dual color affordable focal planes, on-focal plane array biologically inspired image and signal processing techniques and spectral sensing techniques. Pacific Advanced Technology (PAT) and the Air Force Research Lab Munitions Directorate have developed a system which incorporates the best of these capabilities into a single device. The "NeuroSeek" device integrates these technologies into an infrared focal plane array (FPA) which combines multicolor Midwave Infrared/Longwave Infrared (MWIR/LWIR) radiometric response with on-focal plane "smart" neuromorphic analog image processing. The Readout and Processing Integrated Circuit (ROPIC) Very Large Scale Integration (VLSI) chip which was developed under this effort will be hybridized to a dual color detector array to produce the NeuroSeek FPA, which will have the capability to fuse multiple pixel-based sensor inputs directly on the focal plane (pixel based sensor fusion). Great advantages are afforded by application of massively parallel processing algorithms to image data in the analog domain; the high speed and low power consumption of this device mimic operations performed in the human retinal(1,2). C1 USAF, Res Lab, MNGI, Eglin AFB, FL 32542 USA. RP McCarley, PL (reprint author), USAF, Res Lab, MNGI, Eglin AFB, FL 32542 USA. NR 0 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 0-8194-2809-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3360 BP 13 EP 27 DI 10.1117/12.321759 PG 15 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL85J UT WOS:000076932500002 ER PT B AU Banaszak, D Fabian, M Bowers, C AF Banaszak, D Fabian, M Bowers, C GP IES TI Evaluation of unsupported structural exciters SO INSTITUTE OF ENVIRONMENTAL SCIENCES AND TECHNOLOGY - 1998 PROCEEDINGS: DESIGN, TEST, AND EVALUATION PRODUCT RELIABILITY LA English DT Proceedings Paper CT 44th Annual Technical Meeting of the Institute-of-Environmental-Sciences-and-Technology on the 21st Century - A New Frontier in International Information Exchange CY APR 26-MAY 01, 1998 CL PHOENIX, AZ SP Inst Environm Sci & Technol DE calibration; vibration; structures; unsupported exciters; statistics; experimental design AB Wright Laboratory is evaluating a new vibration calibration technique that allows one person to perform end-to-end calibrations of a structural dynamics measurement system including mounted transducers, signal conditioning and recorder. This new technique uses an unsupported structural exciter(USE). This technique stimulates structural measurement transducers, inside of structures, with a measurable acceleration revel. If a transducer is mounted on a test structure, it is difficult to stimulate the transducer with a known physical input. A person must hold the exciter or attach a conventional vibration shaker to a structure. Two persons are required to calibrate, one at the transducer holding the exciter and one at the measurement system. Now one person can calibrate. Laboratory engineers conducted an experiment to evaluate a commercial off-the-shelf vibration paging system consisting of a master control unit and 8 individual exciters(pagers) to excite accelerometers mounted on structures. An accelerometer on the front of the structure measured the vibration Input. This payer discusses the instrumentation and a completely randomized block design experiment consisting of three 2-level experimental factors: structural material, structural thickness and excitation mode. A blocking factor was each of the 8 different exciters(pagers) serial numbers. For each of the 64 combinations, a technician used a spectrum analyzer to record and compute the output amplitude, fundamental frequency and transfer function between the two accelerometers, This paper presents results from the experiments and describes the new technique. C1 USAF, Struct Div, Flight Dynam Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Banaszak, D (reprint author), USAF, Struct Div, Flight Dynam Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU INST ENVIRONMENTAL SCIENCES PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 USA BN 1-877862-63-0 PY 1998 BP 172 EP 179 PG 2 WC Acoustics; Environmental Sciences; Instruments & Instrumentation SC Acoustics; Environmental Sciences & Ecology; Instruments & Instrumentation GA BL14X UT WOS:000074492400022 ER PT S AU Gluck, KA Shute, VJ Anderson, JR Lovett, MC AF Gluck, KA Shute, VJ Anderson, JR Lovett, MC BE Goettl, BP Halff, HM Redfield, CL Shute, VJ TI Deconstructing a computer-based tutor: Striving for better learning efficiency in stat lady SO INTELLIGENT TUTORING SYSTEMS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 4th International Conference on Intelligent Tutoring Systems (ITS 98) CY AUG 16-19, 1998 CL SAN ANTONIO, TEXAS SP AFRL, Mei Technol, St Marys Univ, Galaxy Scientif Command Technol, Univ Texas San Antonio AB This paper is a prospective report of an ongoing design project involving a computer-based tutoring system called Stat Lady (Shute & Gluck, 1994). Previous studies have shown considerable improvement on curriculum objectives as a result of interation with the tutor. The goal now is to try to improve on learning efficiency, defined as knowledge gain per unit of time. The question we will be asking in this study is: What can we peel away from the tutor to make it a more efficient teaching tool, without having a negative impact on curriculum learning? Additionally, as we remove pieces of the tutor, what effect (if any) will that have on the subjective enjoyment of the learning experience? The study in progress investigates these issues in a 2x2 factorial design varying the presence or absence of contextualized instruction and problem solving across the presence or absence of certain interface features that were an integral part of the original tutor. C1 Carnegie Mellon Univ, Dept Psychol, Pittsburgh, PA 15217 USA. USAF, Res Lab, HEJT, Lackland AFB, TX 78236 USA. RP Gluck, KA (reprint author), Carnegie Mellon Univ, Dept Psychol, Pittsburgh, PA 15217 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-64770-8 J9 LECT NOTES COMPUT SC PY 1998 VL 1452 BP 66 EP 75 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Education, Scientific Disciplines SC Computer Science; Education & Educational Research GA BN52L UT WOS:000082115200012 ER PT S AU Shute, VJ Torreano, LA Willis, RE AF Shute, VJ Torreano, LA Willis, RE BE Goettl, BP Halff, HM Redfield, CL Shute, VJ TI DNA - Uncorking the bottleneck in knowledge elicitation and organization SO INTELLIGENT TUTORING SYSTEMS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 4th International Conference on Intelligent Tutoring Systems (ITS 98) CY AUG 16-19, 1998 CL SAN ANTONIO, TEXAS SP AFRL, Mei Technol, St Marys Univ, Galaxy Scientif Command Technol, Univ Texas San Antonio AB There are two main purposes of this paper. First, we describe a novel cognitive tool that was designed to aid in knowledge elicitation and organization for instructional purposes - specifically to be used for intelligent tutoring system development. This automated approach to knowledge elicitation is embodied in a program called DNA (Decompose, Network, Assess). Our aim for this tool is to increase the efficiency of developing the expert model - often referred to as the bottleneck in developing intelligent instructional systems. The second purpose is to present a first-order summative evaluation of the tool's efficacy. Specifically, we used DNA with three statistical experts to explicate their knowledge structures related to measures of central tendency. In short, we found that DNA can be used as a standalone program to effectively elicit relevant information on which to build instruction. This was achieved in hours compared to months for conventional elicitation procedures. C1 USAF, Res Lab, Lackland AFB, TX 78236 USA. Natl Res Council, Lackland AFB, TX 78236 USA. Galaxy Sci Corp, Lackland AFB, TX 78236 USA. RP Shute, VJ (reprint author), USAF, Res Lab, 1880 Carswell Ave, Lackland AFB, TX 78236 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-64770-8 J9 LECT NOTES COMPUT SC PY 1998 VL 1452 BP 146 EP 155 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Education, Scientific Disciplines SC Computer Science; Education & Educational Research GA BN52L UT WOS:000082115200020 ER PT S AU Connolly, CA Johnson, J Lexa, C AF Connolly, CA Johnson, J Lexa, C BE Goettl, BP Halff, HM Redfield, CL Shute, VJ TI AVATAR: An intelligent air traffic control simulator and trainer SO INTELLIGENT TUTORING SYSTEMS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 4th International Conference on Intelligent Tutoring Systems (ITS 98) CY AUG 16-19, 1998 CL SAN ANTONIO, TEXAS SP AFRL, Mei Technol, St Marys Univ, Galaxy Scientif Command Technol, Univ Texas San Antonio AB A continuum of simulation-based training systems currently exists and can be distinguished not only by their level of fidelity or graphical realism, but also by their level of intelligence. Intelligence in this case, is considered to be the ability of a system to diagnose and provide adaptive instruction and remediation. In this paper we discuss an intelligent air traffic control simulator and trainer called the Advanced Virtual Adaptive Tutor for Air Traffic Control Readiness (AVATAR). Unlike most of today's simulations, AVATAR is based upon theoretically grounded instructional strategies and uses intelligent technologies that enable the system to diagnose, instruct, and remediate students based upon their performance while providing dynamically interactive simulation. A discussion of instructional deficiencies within current training simulations is presented as well as information about the instructional strategies and intelligent technologies used within AVATAR to overcome those shortcomings. C1 Galaxy Sci Corp, San Antonio, TX 78216 USA. USAF, Res Lab, Brooks AFB, TX 78235 USA. RP Connolly, CA (reprint author), Galaxy Sci Corp, 7334 Blanco Rd,Suite 206, San Antonio, TX 78216 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-64770-8 J9 LECT NOTES COMPUT SC PY 1998 VL 1452 BP 534 EP 543 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Education, Scientific Disciplines SC Computer Science; Education & Educational Research GA BN52L UT WOS:000082115200059 ER PT B AU Davis, TM Tomlinson, BJ AF Davis, TM Tomlinson, BJ BE DewHughes, D Scurlock, RG Watson, JHP TI Air force research laboratory cryocooler technology development SO INTERNATIONAL CRYOGENIC ENGINEERING CONFERENCE 1998 LA English DT Proceedings Paper CT 17th International Cryogenic Engineering Conference CY JUL 14-17, 1998 CL BOURNEMOUTH, ENGLAND SP Air Prod Ltd, A S Sci Ltd, BOC Ltd, BOC Proc Plants, British Cryoengn Soc, Elsevier Sci Ltd, HPC Engn plc, Hyrolec Tech Serv Ltd, Int Cryogen Engn Comm, Int Inst Refrigerat, Oxford Instruments Ltd, Linde Cryogen Ltd, Merck Ltd, Univ Southampton, Weka AG 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 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. C1 USAF, Res Lab, AFRL, VSSS, Kirtland AFB, NM 87117 USA. RP Davis, TM (reprint author), USAF, Res Lab, AFRL, VSSS, 3550 Aberdeen Ave SE,Bldg 30117 Manzano, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND BN 0-7503-0597-5 PY 1998 BP 213 EP 216 PG 4 WC Thermodynamics; Engineering, Mechanical; Mechanics; Physics, Applied; Physics, Condensed Matter SC Thermodynamics; Engineering; Mechanics; Physics GA BM16L UT WOS:000077869200042 ER PT J AU Bell, HH Waag, WL AF Bell, HH Waag, WL TI Evaluating the effectiveness of flight simulators for training combat skills: A review SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article ID AIR COMBAT AB The military is focusing a great deal of effort on developing virtual world technologies that will allow training combat skills in flight simulators. Considerably less attention is being directed toward documenting the effectiveness of such training. In this article, we review Air Force and Navy efforts to evaluate the effectiveness of training the combat skills necessary for attack and fighter aircraft in flight simulators. The majority of these efforts indicate that simulation can be a valuable complement to the aircraft. Unfortunately, this conclusion is based primarily on opinion data from experienced aviators. There are very few transfer of training experiments, and those experiments have examined only a limited set of combat tasks. We also describe the typical paradigms used to conduct training evaluations and outline a multistep evaluation program for determining training effectiveness. C1 USAF, Res Lab, Human Effectiveness Directorate, Warfighter Training Res Div, Mesa, AZ 85206 USA. RP Bell, HH (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Warfighter Training Res Div, 6001 S Power Rd,Bldg 558, Mesa, AZ 85206 USA. NR 47 TC 38 Z9 38 U1 2 U2 9 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 1050-8414 J9 INT J AVIAT PSYCHOL JI Int. J. Aviat. Psychol. PY 1998 VL 8 IS 3 BP 223 EP 242 DI 10.1207/s15327108ijap0803_4 PG 20 WC Psychology, Applied SC Psychology GA 104XL UT WOS:000075041800004 ER PT J AU See, JE Vidulich, MA AF See, JE Vidulich, MA TI Computer modeling of operator mental workload and situational awareness in simulated air-to-ground combat: An assessment of predictive validity SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article AB The predictive validity of computer modeling of operator mental workload and situational awareness during a simulated air-to-ground combat mission was assessed. In Phase 1 of the study, 12 participants completed a series of simulated flights and provided Subjective Workload Assessment Technique (SWAT) ratings of workload and Situational Awareness Rating Technique (SART) ratings of situational awareness. In Phase 2, computer models of the combat mission were constructed using the Micro Saint modeling tool. The visual, auditory, kinesthetic, cognitive, and psychomotor components of workload associated with each task comprising the mission were estimated and used to derive measures of average and peak workload. The results from the flight-simulator data versus the Micro Saint data were similar but not identical, indicating that the computer models were partially but not completely valid predictors of mental workload and situational awareness. The computer modeling appeared to be a more effective predictor of situational awareness than mental workload. C1 AFRL, HECP, Crew Syst Interface Div, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. Logicon Tech Serv Inc, Dayton, OH USA. RP Vidulich, MA (reprint author), AFRL, HECP, Crew Syst Interface Div, Human Effectiveness Directorate, 2255 H St, Wright Patterson AFB, OH 45433 USA. NR 25 TC 2 Z9 2 U1 2 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1050-8414 J9 INT J AVIAT PSYCHOL JI Int. J. Aviat. Psychol. PY 1998 VL 8 IS 4 BP 351 EP 375 DI 10.1207/s15327108ijap0804_3 PG 25 WC Psychology, Applied SC Psychology GA 124HN UT WOS:000076176500003 ER PT J AU Winn, RC Green, RS AF Winn, Robert C. Green, Robert S. TI Applying Total Quality Management to the Educational Process SO INTERNATIONAL JOURNAL OF ENGINEERING EDUCATION LA English DT Article AB Total Quality Management (TQM) is recognized as an important management philosophy and is widely used in US industry. It has been used very successfully in the development and acquisition of systems such as satellites and aircraft to preparing officer performance reports. Over the last few years, TQM has been applied in the education industry. Most of the applications have been in the administrative side of the institutions, but some schools have applied TQM to curriculum development. The Air Force Academy has been a leader in this application of TQM. In this paper, the principles of TQM are described with an emphasis on the importance of identifying the customer and analyzing the processes. The 14 Points of Dr. W. Edwards Deming, which form a framework for the implementation of the TQM, are individually applied to the academic environment based on the experience gained at the Air Force Academy. C1 [Winn, Robert C.] Engn Syst Inc, Colorado Springs, CO 80919 USA. [Green, Robert S.] USAF, Directorate Tech Training, Randolph AFB, TX 78150 USA. RP Winn, RC (reprint author), Engn Syst Inc, 4775 Centennial Blvd,Suite 106, Colorado Springs, CO 80919 USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU TEMPUS PUBLICATIONS PI DURRUS, BANTRY PA IJEE , ROSSMORE,, DURRUS, BANTRY, COUNTY CORK 00000, IRELAND SN 0949-149X J9 INT J ENG EDUC JI Int. J. Eng. Educ PY 1998 VL 14 IS 1 BP 24 EP 29 PG 6 WC Education, Scientific Disciplines; Engineering, Multidisciplinary SC Education & Educational Research; Engineering GA V12WP UT WOS:000207629600004 ER PT J AU Gao, ZJ Zuiker, JR AF Gao, ZJ Zuiker, JR TI On the analysis of cross-ply laminates with micro-cracks and inelastic deformation SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article ID TRANSVERSE CRACKING; COMPOSITES; STRAIN; GLASS AB For cross-ply laminates micro-matrix cracks in the 90 degrees plies and inelastic deformation in the 0 degrees and 90 degrees plies are two major forms of damage which affect the long-term durability of the materials. It is crucial to develop a mechanics based approach to incorporate both micro-cracks and inelastic deformation of the composite materials based on the response of the 0 degrees and 90 degrees plies in order to accurately predict the response of the materials in service environments and to assist in optimizing the materials system for best performance. However, such a task leads to severe mathematical difficulties, primarily due to the zero traction conditions on the crack surfaces, the complicated constitutive relations governing the inelastic deformation and the interaction between the cracks and the inelastic deformation. In this paper, a general framework for the analysis of cross-ply laminates with micro-matric cracks and inelastic deformation is proposed. For this purpose admissible stress fields are constructed which satisfy equilibrium and all boundary and interface conditions. The principle. of minimum complementary energy is utilized to derive a differential equation for the stress function from which the stress field of the composite can be derived. The inhomogeneous terms of the differential equation involve the inelastic strains which are loading history dependent. The Green's function of the differential equation is then obtained. Using the Green's function and a constitutive equation, two-dimensional stress and strain states in the composite at any time are represented by an integral of the Green's function and the inelastic strains. accumulated up to that time. This new analysis takes into consideration the microcrack-microcrack interaction, as well as the interaction between the microcracks and the inelastic deformation, and provides a point-wise variation of the stress field instead of average stress field as most of the analytical approaches yield. The interactions of matrix cracks and creep deformation of an eight-harness satin weave (8HSW) Nextel 610/Aluminosilicate ceramic matrix composite is studied using the proposed model. The predicted creep Strain of the composite shows good correlation with experimental data at different levels of temperature and stress conditions. The distribution of stresses and strains provides important information on the response of the composite. (C) 1997 Elsevier Science Ltd. C1 CLARKSON UNIV,DEPT MECH & AERONAUT ENGN,POTSDAM,NY 13699. USAF,WRIGHT LAB,MAT DIRECTORATE,WRIGHT PATTERSON AFB,OH 45433. RI Gao, Zhanjun/C-7293-2011 NR 29 TC 1 Z9 1 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD JAN PY 1998 VL 35 IS 1-2 BP 107 EP 127 DI 10.1016/S0020-7683(97)00060-7 PG 21 WC Mechanics SC Mechanics GA YJ567 UT WOS:A1998YJ56700007 ER PT J AU Prasad, YVRK Seshacharyulu, T AF Prasad, YVRK Seshacharyulu, T TI Modelling of hot deformation for microstructural control SO INTERNATIONAL MATERIALS REVIEWS LA English DT Review ID DYNAMIC MATERIAL BEHAVIOR; PROCESSING MAP; MECHANICAL-BEHAVIOR; AISI 304L; RECRYSTALLIZATION; WORKING; ALUMINUM; SUPERPLASTICITY; OPTIMIZATION; METALS AB Bulk metal working processes are carried out at elevated temperatures where the occurrence of simultaneous softening processes would enable the imposition of large strains in a single step or multiple steps. Hot working also causes a significant change in the microstructure of the material and this contributes to one part of workability generally referred to intrinsic workability, which is sensitive to the initial conditions of the material and the process parameters. The other part, related to the state of stress existing in the deformation zone, is specific to a metal working process and may be controlled by changing the applied state of stress and/or the geometry of the deformation zone. An understanding of the constitutive behaviour of the material is essential for the optimisation of the intrinsic workability and control of microstructural evolution during hot working. In recent years, modelling techniques have been developed for this purpose and these are critically reviewed. These include: (1) the kinetic model, (2) the atomistic model, (3) the dynamic materials model, and (4) other models including activation energy maps with stability criteria and polar reciprocity model. Since the first two models do not lead to workability optimisation directly and are not useful for commercial alloys, the dynamic materials model has been developed. This model forms a bridge between the continuum mechanics and the microstructural mechanisms occurring during hot deformation, and consists of principles of irreversible thermodynamics of large plastic flow. The dissipated power is related to the rate of entropy production due to metallurgical processes obtained by partitioning the total power between that due to the temperature rise and the microstructural change. In view of the viscoplastic nature of hot deformation, the strain rate sensitivity of flow stress has been found to be the power partitioning factor. The development of processing maps using this model, their interpretation and application for optimising hot workability and control of microstructure are reviewed. The development of activation energy maps and their use in the control of microstructure are useful for obtaining robust process control for microstructural optimisation, while the use of the stability criteria puts undue restrictions on the processing regimes. Several mechanisms of hot deformation, with special reference to dynamic recrystallisation, are discussed in the light of results from processing maps obtained on a wide range of materials. Finally, the application of the processing maps in designing bulk metal working processes is briefly explained. C1 Indian Inst Sci, Dept Met, Bangalore 560012, Karnataka, India. RP Prasad, YVRK (reprint author), USAF, Res Lab, Mat Proc Design Branch, MLMR, Wright Patterson AFB, OH 45433 USA. NR 79 TC 291 Z9 344 U1 11 U2 58 PU MANEY PUBLISHING PI LEEDS PA STE 1C, JOSEPHS WELL, HANOVER WALK, LEEDS LS3 1AB, W YORKS, ENGLAND SN 0950-6608 EI 1743-2804 J9 INT MATER REV JI Int. Mater. Rev. PY 1998 VL 43 IS 6 BP 243 EP 258 PG 16 WC Materials Science, Multidisciplinary SC Materials Science GA 216YU UT WOS:000081472700002 ER PT B AU Kim, YW AF Kim, YW BE Baker, I Noebe, RD George, EP TI Design fundamentals for gamma TiAl alloys SO INTERSTITIAL AND SUBSTITUTIONAL SOLUTE EFFECTS IN INTERMETALLICS LA English DT Proceedings Paper CT 2nd International Symposium on Interstitial and Substitutional Solute Effects in Intermetallics, at the 1998 TMS Fall Meeting CY OCT 11-15, 1998 CL ROSEMONT, IL SP Minerals Met & Mat Soc AB Phase transformations and microstructural evolution observed in various gamma-TiAl based alloys are discussed, The mechanical properties are summarized and analyzed in duplex as well as fully-lamellar materials over a wide range of grain sizes, From the structure-property relationships, a generalization is made on the desired microstructural features which will result in significant improvements in balanced or specific properties. Further property enhancement, especially in creep resistance achieved by microalloying with carbon and Si, is also discussed. On the basis of the accumulated knowledge, a suggestion is made on a next-generation alloy system for higher temperature use. C1 Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Kim, YW (reprint author), Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 6 Z9 6 U1 0 U2 0 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-413-5 PY 1998 BP 189 EP 200 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BM06Y UT WOS:000077538900013 ER PT B AU Szmulowicz, F Brown, GJ Mitchell, WC Liu, HC Li, L Buchanan, M Wasilewski, ZR Lin, CH AF Szmulowicz, F Brown, GJ Mitchell, WC Liu, HC Li, L Buchanan, M Wasilewski, ZR Lin, CH BE Li, SS Su, YK TI Calculation and photoresponse measurements of the long-wavelength IR absorption in p-type GaAs AlGaAs quantum wells and type-II InAs InGaSb superlattices SO INTERSUBBAND TRANSITIONS IN QUANTUM WELLS: PHYSICS AND DEVICES LA English DT Proceedings Paper CT International Workshop on Intersubband Transitions in Quantum Wells - Physics and Applications CY DEC 15-18, 1997 CL NATL CHENG KUNG UNIV, TAINAN, TAIWAN SP Natl Sci Council & Minist Educ, Off Naval Res-Asia, US Army Res Off-Far E HO NATL CHENG KUNG UNIV DE p-type; quantum well; infrared detector; superlattice; GaAs AlGaAs; InAs InGaSb ID INAS/INXGA1-XSB SUPERLATTICES AB This paper describes the design, growth, and photoresponse measurement of band-gap engineered GaAs/AlGaAs quantum well infrared photodetectors (QWIPs) and InAs/InGaSb superlattice (SL) infrared (IR) detector structures. The electronic structure and the optical absorption of these structures are calculated as a function of their structural and material parameters using a newly developed 8x8 envelope-function approximation (EFA) formalism. Based on the model results, optimized photodetector structures are grown via molecular-beam epitaxy (MBE) and their photoresponse measured. Good experimental-theoretical agreement is obtained regarding the long-wavelength threshold and absorption shape. C1 USAF, Wright Lab, Mat Directorate, MLPO, Wright Patterson AFB, OH 45433 USA. RP Szmulowicz, F (reprint author), USAF, Wright Lab, Mat Directorate, MLPO, Wright Patterson AFB, OH 45433 USA. NR 25 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC PUBLISHERS PI NORWELL PA 101 PHILIP DRIVE, ASSINIPPI PARK, NORWELL, MA 02061 USA BN 0-7923-8164-5 PY 1998 BP 76 EP 83 PG 8 WC Optics; Physics, Applied; Physics, Multidisciplinary SC Optics; Physics GA BN28B UT WOS:000081415100011 ER PT B AU Welch, RJ Yang, AT AF Welch, RJ Yang, AT GP IEEE IEEE TI Substrate coupling analysis and simulation for an industrial phase-locked loop SO ISCAS '98 - PROCEEDINGS OF THE 1998 INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOLS 1-6 LA English DT Proceedings Paper CT IEEE International Symposium on Circuits and Systems (ISCAS 98) CY MAY 31-JUN 03, 1998 CL MONTEREY, CA SP IEEE, Naval Postgraduate Sch, Monterey, Calif AB Current injected into the common chip substrate from fast-switching digital devices can affect the operation of sensitive analog circuits in mixed signal designs. An industrial Phase-Locked Loop(PLL) is analyzed with the non-ideal substrate modeled to show the effects of substrate coupling. Detailed simulation results strongly correlate to the measured circuit jitter. Additional results show that well guard structures should not be used and the effectiveness of ohmic guarding structures depends on number, location in the layout, and the bias scheme. C1 USAF, Res Lab, Electron Device Div, Av Directorate, Dayton, OH 45433 USA. RP Welch, RJ (reprint author), USAF, Res Lab, Electron Device Div, Av Directorate, Dayton, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4455-3 PY 1998 BP E94 EP E97 PG 4 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BL35E UT WOS:000075224600753 ER PT B AU Blitch, J AF Blitch, J GP IEEE TI Semi-autonomous tactical robots for urban operations SO JOINT CONFERENCE ON THE SCIENCE AND TECHNOLOGY OF INTELLIGENT SYSTEMS LA English DT Proceedings Paper CT Joint Conference on the Science and Technology of Intelligent Systems ISIC/CIRA/ISAS CY SEP 14-17, 1998 CL NATL INST STAND & TECHNOL, GAITHERSBURG, MD SP IEEE, Control Syst Soc, Natl Sci Fdn, USA, Army Res Off HO NATL INST STAND & TECHNOL AB A common aspect of virtually any projection for future military operations for the 21(st) Century is the need function effectively in urban environments. The dynamic nature urban activity and human discord often creates very frustrating and complex situations requiring a wide variety of diplomatic and military employment options for effective crisis resolution. As hostile elements become more sophisticated and advanced technology becomes increasingly available to irresponsible state actors, U.S. Armed Forces will inevitably be called upon to execute extremely demanding and complicated urban operations in support of national security objectives. This paper outlines the advantages enjoyed through the employment of Miniature Man-packed Robotic Vehicles (MMRVs) in urban environments, and calls for a redirection of unmanned systems development toward low cost semi-autonomous portable platforms. A review of ground robotic platforms is provided first, followed by a discussion of operational voids posed by Military Operations in Urban Terrain (MOUT). A review of machine competencies and limitations follows next Portable (man-packed) mobile robots are then presented as a means to address MOUT voids as well as other problem areas for other government agencies outside the Department of Defense. The paper concludes that human launched and supervised miniature robots possess enormous potential to compensate for the many daunting challenges involved with urban operations. C1 HQ USSOCOM SOAL T SOJUSP, MacDill AFB, FL 33621 USA. RP Blitch, J (reprint author), HQ USSOCOM SOAL T SOJUSP, 7701 Tampa Pt Blvd, MacDill AFB, FL 33621 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4423-5 PY 1998 BP 783 EP 794 DI 10.1109/ISIC.1998.713819 PG 12 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Computer Science GA BL60A UT WOS:000075973800137 ER PT J AU Schreck, SJ Faller, WE Helin, HE AF Schreck, SJ Faller, WE Helin, HE TI Pitch rate and Reynolds number effects on unsteady boundary-layer transition and separation SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA 25th Fluid Dynamics Conference CY JUN 20-23, 1994 CL COLORADO SPRINGS, COLORADO SP Amer Inst Aeronaut & Astronaut AB A NACA 0015 airfoil was pitched at a constant rate through static stall to elevated angles of attack, Shear stress measurements of high spatial and temporal resolution were performed near the airfoil leading edge, in the vicinity of subsequent dynamic stall vortex initiation, Using these data, unsteady boundary-layer reversal and transition were characterized for a range of nondimensional pitch rates and Reynolds numbers. Analyses revealed the independent influences of nondimensional pitch rate anti Reynolds number upon unsteady boundary-layer reversal and transition, Temporal sand spatial relationships between unsteady boundary-lager reversal and transition imply that unsteady boundary-layer reversal is a precursor and principal determinant in unsteady boundary-layer transition, Comprehension of these and other fundamental unsteady flow physics are crucial For the control of dynamically-separated flows generated by maneuvering aircraft, rotercraft, and wind energy machines. C1 USAF, Off Sci Res, Washington, DC 20332 USA. Johns Hopkins Univ, Dept Mech Engn, Baltimore, MD 21218 USA. USAF, Operat Test & Evaluat Ctr, Kirtland AFB, NM 87117 USA. RP Schreck, SJ (reprint author), USAF, Off Sci Res, 110 Duncan Ave,Room B115, Washington, DC 20332 USA. NR 18 TC 9 Z9 9 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 JAN-FEB PY 1998 VL 35 IS 1 BP 46 EP 52 DI 10.2514/2.2258 PG 7 WC Engineering, Aerospace SC Engineering GA YV907 UT WOS:000071876300008 ER PT J AU Kolonay, RM Yang, HTY AF Kolonay, RM Yang, HTY TI Unsteady aeroelastic optimization in the transonic regime SO JOURNAL OF AIRCRAFT LA English DT Article AB A methodology. for including transonic flutter requirements in the preliminary automated structural design environment is developed and tested, The problem of minimizing structural weight while satisfying behavioral constraints is stated in nonlinear mathematical programming form and is solved using a gradient-based optimizing technique, The structure is modeled by using finite elements, and the associated design variables consist of the structural properties thicknesses of skins, spars, and ribs; cross-sectional areas of posts and spar and rib raps; and concentrated masses, The method requires that the transonic unsteady aerodynamic forces be represented in the frequency or Laplace domain, In this work, the indicial response method is used fu transform time-domain aerodynamic forces found by solving the transonic small disturbance (TSD) equations into the Laplace domain, The indicial responses are calculated about static aeroelastic equilibriums round using file TSD equations for the steady aerodynamics. Once in the Laplace domain, the unsteady aerodynamic forces are used to determine system dynamic stability by the p-method and in semianalytic equations Tor the flutter constraint sensitivities, With constraint values and the required gradients, a Taylor series approximation is used to develop ant approximate nonlinear mathematical programming problem for weight minimization. This approximate optimization problem is iteratively solved by the method of modified feasible directions until convergence of the exact problem is obtained, Examples of the redesign methodology are given for the simultaneous consideration of constraints on transonic flutter stresses, and displacements. Results found using nonlinear aerodynamics show that designs can differ considerably from those obtained using linear unsteady aerodynamics when in the transonic flight regime. C1 USAF, Res Lab, Struct Div, Flight Dynam Directorate, Wright Patterson AFB, OH 45433 USA. Univ Calif Santa Barbara, Dept Mech & Environm Engn, Santa Barbara, CA 93106 USA. RP Kolonay, RM (reprint author), USAF, Res Lab, Struct Div, Flight Dynam Directorate, Wright Patterson AFB, OH 45433 USA. NR 22 TC 1 Z9 1 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 JAN-FEB PY 1998 VL 35 IS 1 BP 60 EP 68 DI 10.2514/2.2260 PG 9 WC Engineering, Aerospace SC Engineering GA YV907 UT WOS:000071876300010 ER PT J AU Nees, CD Canfield, RA AF Nees, CD Canfield, RA TI Methodology for implementing fracture mechanics in global structural design of aircraft SO JOURNAL OF AIRCRAFT LA English DT Article; Proceedings Paper CT AIAA/ASME/ASCE/AHS/ASC 37th Structures, Structural Dynamics, and Materials Conference CY APR 15-17, 1996 CL SALT LAKE CITY, UTAH SP AIAA, ASME, ASCE, AHS, ASC AB The analysis and design criteria of fracture mechanics are investigated for implementation with the automated structural optimization system (ASTROS) global optimization design tool. The main focus is the optimal design of aircraft wing panels by applying fracture mechanics design criteria within the global finite element model. This effort consists of four main phases: investigation of fracture mechanics analysis methods and design criteria, formulation of a computational technique consistent with global optimization requirements, integration of the technique into the ASTROS design tool, and demonstration of the results. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. USAF, Off Sci Res, Plans & Budget Div, Washington, DC 20332 USA. RP Nees, CD (reprint author), USAF, Res Lab, WL-FIBD Bldg 45 Suite 1,2133 8th St, Wright Patterson AFB, OH 45433 USA. NR 15 TC 4 Z9 4 U1 0 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 JAN-FEB PY 1998 VL 35 IS 1 BP 131 EP 138 DI 10.2514/2.2270 PG 8 WC Engineering, Aerospace SC Engineering GA YV907 UT WOS:000071876300019 ER PT J AU Fang, ZQ Reynolds, DC Look, DC Paraskevopoulos, NG Anderson, TE Jones, RL AF Fang, ZQ Reynolds, DC Look, DC Paraskevopoulos, NG Anderson, TE Jones, RL TI Effect of high-temperature annealing on electrical and optical properties of undoped semi-insulating GaAs SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SEMIINSULATING GAAS; BULK GAAS; CRYSTALS; DEFECTS; TRAPS AB A comprehensive characterization, including room temperature Hall effect, near infrared absorption, temperature dependent dark current and photocurrent (using 1.13 eV light), normalized thermally stimulated current (NTSC), photoluminescence at 4.2 K in both near band edge and deep level regions, and selective pair photoluminescence (SPL) at 2 K, has been carried out on undoped semi-insulating GaAs samples, cut from four wafers which were grown by the low pressure liquid encapsulated Czochralski technique and annealed by three different schedules: a 1100 degrees C anneal with either fast or slow cooling, or a 1000 degrees C standard anneal. The 1100 degrees C anneal clearly introduces higher concentrations of NTSC traps near 0.3 and 0.5 eV, a PL center at 0.8 eV, and acceptor centers, which are mainly due to the point defects and increase the resistivity. Slow cooling to some extent reduces all of these additional centers. The SPL measurements show changes in the relative intensities of C, Zn, and Si related emissions with changes in annealing conditions. (C) 1998 American Institute of Physics. C1 Wright State Univ, Res Ctr, Dayton, OH 45435 USA. Wright State Univ, Dept Phys, Dayton, OH 45435 USA. Litton Airtron, Elect Mat Grp, Morris Plains, NJ 07950 USA. AADM, Wright Lab, Av Directorate, Wright Patterson AFB, OH 45433 USA. RP Fang, ZQ (reprint author), Wright State Univ, Res Ctr, Dayton, OH 45435 USA. NR 27 TC 3 Z9 3 U1 1 U2 1 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 JAN 1 PY 1998 VL 83 IS 1 BP 260 EP 265 DI 10.1063/1.366680 PG 6 WC Physics, Applied SC Physics GA YP836 UT WOS:000071320400037 ER PT J AU Liu, HC Li, L Buchanan, M Wasilewski, ZR Brown, GJ Szmulowicz, F Hegde, SM AF Liu, HC Li, L Buchanan, M Wasilewski, ZR Brown, GJ Szmulowicz, F Hegde, SM TI A study of GaAs/AlGaAs p-type quantum well infrared photodetectors with different barrier heights SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID BACKGROUND LIMITED PERFORMANCE; INTERSUBBAND TRANSITIONS; DARK CURRENT; ABSORPTION; WAVELENGTH AB We report on a systematic study of a set of GaAs/AlGaAs p-type quantum well infrared photodetectors with varying barrier heights. The detector cutoff wavelength decreases with increasing barrier height. Experimental photoresponse spectra are in good agreement with calculated ground-state to continuum absorption spectra, based on a multiband envelope-function model. The measured dark current decreases with increasing barrier height. An estimate of the low-field dark current gives good agreement with the measured dark current. (C) 1998 American Institute of Physics. C1 Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0R6, Canada. USAF, Wright Lab, MLPO, Wright Patterson AFB, OH 45433 USA. RP Liu, HC (reprint author), Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0R6, Canada. EM h.c.liu@nrc.ca NR 21 TC 22 Z9 22 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 1 PY 1998 VL 83 IS 1 BP 585 EP 587 DI 10.1063/1.366644 PG 3 WC Physics, Applied SC Physics GA YP836 UT WOS:000071320400087 ER PT J AU Chen, JK Beraun, JE AF Chen, JK Beraun, JE TI A non-quadratic elasticity model suitable for metal matrix composites SO JOURNAL OF COMPOSITE MATERIALS LA English DT Article DE 3-D anisotropic plasticity; non-quadratic yield function; uniform dilatation; non-associative flow rule; metal matrix composite ID BORON ALUMINUM COMPOSITE; FIBER COMPOSITES; PLASTIC BEHAVIOR; FLOW RULE AB Based on the assumption that uniform dilatation has negligible effect on the yield point, a high-order yield function of non-equal stress exponents in conjunction with a non-associated flow rule is proposed to formulate 3-D plastic constitutive equations for fibrous metal matrix composites (MMC). The involved nine plastic parameters, six for the yield criterion and three for the plastic potential, can be easily calibrated with the macro stress-strain data of simple tension, pure shear, and bi-axial tension tests. It is demonstrated numerically that this theory describes anisotropic plasticity of boron-aluminum (B/Al) composites very well. It is also shown that the uniform dilatation assumption is adequate for other fiber composites. By properly selecting the plastic parameters, the present model can reduce to the nine-parameter quadratic yield function developed for graphite fiber/organic matrix composites [1], Hill's quadratic yield model [2], and von Mises and Tresca isotropic yield criteria. C1 USAF, Directed Energy Effects Res Branch, Kirtland AFB, NM 87117 USA. RP Chen, JK (reprint author), USAF, Directed Energy Effects Res Branch, Kirtland AFB, NM 87117 USA. NR 23 TC 5 Z9 5 U1 1 U2 3 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0021-9983 J9 J COMPOS MATER JI J. Compos Mater. PY 1998 VL 32 IS 23 BP 2156 EP 2176 PG 21 WC Materials Science, Composites SC Materials Science GA 141JB UT WOS:000077138900003 ER PT J AU Baker, JF Murchison, DF Charlton, DG Vandewalle, K AF Baker, JF Murchison, DF Charlton, DG Vandewalle, K TI Cross compatibility of fifth-generation dentin bonding and composite systems. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. DIS, Brooks AFB, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 215 BP 132 EP 132 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800213 ER PT J AU Hilton, TJ Schwartz, RS Ferracane, JL AF Hilton, TJ Schwartz, RS Ferracane, JL TI Fifth generation bonding agent application technique effects on bond strength. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USAF, Dent Invest Serv, San Antonio, TX USA. Univ Texas, Hlth Sci Ctr, Sch Dent, San Antonio, TX 78284 USA. OHSU, Sch Dent, Portland, OR USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 214 BP 132 EP 132 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800216 ER PT J AU Esquivel, C Murchison, DF Belles, DM Hensley, D AF Esquivel, C Murchison, DF Belles, DM Hensley, D TI Subsurface disinfection of denture acrylic resin. SO JOURNAL OF DENTAL 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 AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 285 BP 141 EP 141 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800284 ER PT J AU Taylor, JS Norling, BK Alder, ME Dahlen, RT Erickson, DM Schmitt, SM AF Taylor, JS Norling, BK Alder, ME Dahlen, RT Erickson, DM Schmitt, SM TI Influence of computerized tomography parameters on stereolithographic model quality. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. UTHSCSA, San Antonio, TX USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 741 BP 198 EP 198 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800738 ER PT J AU Bedinghaus, RM Murchison, DF Powers, JM Roberts, HW AF Bedinghaus, RM Murchison, DF Powers, JM Roberts, HW TI Accelerated aging effect on shear strength for a bonding agent. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Houston Biomat Res Ctr, Houston, TX USA. DIS, Brooks AFB, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 792 BP 204 EP 204 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800791 ER PT J AU Poth, ME Carnes, DL AF Poth, ME Carnes, DL TI Periodontal ligament cell cultures established in low calcium medium are not enriched in osteoblast-like cells. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Univ Texas, Hlth Sci 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 AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 865 BP 214 EP 214 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684800863 ER PT J AU Cardon, PN Charlton, DG Murchison, DF Hilton, TJ AF Cardon, PN Charlton, DG Murchison, DF Hilton, TJ TI Dentin desensitizer effects on resin cement tensile bond strength. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. USAF, Dent Invest Serv, Brooks AFB, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1061 BP 238 EP 238 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801055 ER PT J AU Worthington, RB Murchison, DF Vandewalle, KS AF Worthington, RB Murchison, DF Vandewalle, KS TI Incisal edge reattachment: The effect of preparation utilization and design. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1238 BP 260 EP 260 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801233 ER PT J AU Van Dermark, JG Murchison, DF Moore, WS Canaan, RL AF Van Dermark, JG Murchison, DF Moore, WS Canaan, RL TI Forensic potential of retained sealants following exposure to environmental extremes. SO JOURNAL OF DENTAL RESEARCH 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 AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1245 BP 261 EP 261 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801237 ER PT J AU Karpay, RI Dove, SB Plamondon, TJ Mills, SE AF Karpay, RI Dove, SB Plamondon, TJ Mills, SE TI Efficacy of metal ions to control dental unit planktonic bacteria SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 Univ Texas, Sch Dent, HSCSA, San Antonio, TX 78285 USA. USAF, Dent Invest Serv, San Antonio, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1253 BP 262 EP 262 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801245 ER PT J AU Cocklin, JL Charlton, DG Murchison, DF AF Cocklin, JL Charlton, DG Murchison, DF TI Effect of light distance on polymerization of resin-modified glass ionomer restoratives. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 DIS, Brooks AFB, TX USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1390 BP 279 EP 279 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801386 ER PT J AU Leonard, D Charlton, D Hilton, T AF Leonard, D Charlton, D Hilton, T TI Effect of curing tip diameter on accuracy of commercial radiometers. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 USAF, Dent Invest Serv, Brooks AFB, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1389 BP 279 EP 279 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801382 ER PT J AU Nawiesniak, PJ Murchison, DF Schwartz, RS Gullickson, DC AF Nawiesniak, PJ Murchison, DF Schwartz, RS Gullickson, DC TI Eugenol inhibition of resin modified glass ionomer luting agents. SO JOURNAL OF DENTAL RESEARCH LA English DT Meeting Abstract C1 UTHSC, San Antonio, TX USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSOC DENTAL RESEARCH PI ALEXANDRIA PA 1619 DUKE ST, ALEXANDRIA, VA 22314 USA SN 0022-0345 J9 J DENT RES JI J. Dent. Res. PY 1998 VL 77 SI A MA 1385 BP 279 EP 279 PG 1 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YU125 UT WOS:000071684801380 ER PT J AU Ippel, MJ Meulemans, CJM AF Ippel, MJ Meulemans, CJM TI A cybernetic approach to study the learnability of the logo turtle world SO JOURNAL OF EDUCATIONAL COMPUTING RESEARCH LA English DT Article ID ENVIRONMENTS; COGNITION AB Research has demonstrated that children experience great difficulty in gaining mastery of the syntax and the semantic structure of the LOGO programming environment. The study presented in this article tests the hypothesis that simplification of the semantic structure will facilitate semantic understanding and acquisition of syntax knowledge within the LOGO Turtle World. Two microworlds were designed to carry out the same class of tasks using an identical set of basic commands, but comprising a different semantic structure. They were designed applying the theory of automata and abstract languages. The article demonstrates that different formal grammars can be formulated from one set of terminal symbols (i.e., basic commands of the LOGO Turtle World). Furthermore, it demonstrates how different finite-stare machines correspond with these different grammars. In this study, two finite-state machines are defined: a one-state machine (ORTHO-1) and a four-state machine (ORTHO-4). Both machines can produce analogous rectangular figures in response to sequences of input symbols chosen from an identical input alphabet. Each of these abstract machines was physically realized as a computer-based microworld similar to the LOGO Turtle World. In an experiment with second and third grade children, it was found that the semantically simpler microworld (i.e., ORTHO-1) produced better semantic understanding as well as better mastery of the syntax of the input commands. The result occurred despite the fact that these microworlds used identical input commands. C1 Leiden Univ, NL-2300 RA Leiden, Netherlands. RP Ippel, MJ (reprint author), USAF, Res Lab, 7909 Lindbergh Dr, Brooks AFB, TX 78235 USA. NR 46 TC 0 Z9 0 U1 0 U2 0 PU BAYWOOD PUBL CO INC PI AMITYVILLE PA 26 AUSTIN AVE, AMITYVILLE, NY 11701 USA SN 0735-6331 J9 J EDUC COMPUT RES JI J. Educ. Comput. Res. PY 1998 VL 19 IS 2 BP 191 EP 221 PG 31 WC Education & Educational Research SC Education & Educational Research GA 208UE UT WOS:000081009600005 ER PT J AU Katta, VR Roquemore, WM AF Katta, VR Roquemore, WM TI Numerical studies on trapped-vortex concepts for stable combustion SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT Turbo Asia 1996 Conference CY NOV 05-07, 1996 CL JAKARTA, INDONESIA SP Int Gas Turbine Inst AB Spatially locked vortices in the cavities of a combustor aid in stabilizing the flames. On the other hand these stationary vortices also restrict the entrainment of the main air into the cavity. For obtaining good performance characteristics in a trapped-vortex combustor a sufficient amount of fuel and air must be injected directly into the cavity. This paper describes a numerical investigation performed to understand better the entrainment and residence-time characteristics of cavity flows for different cavity and spindle sizes. A third-order-accurate time-dependent Computational Fluid Dynamics with Chemistry (CFDC) code was used for simulating the dynamic flows associated with forebody-spindle-disk geometry. It was found from the nonreacting flow simulations that the drag coefficient decreases with cavity length and that an optimum size exists for achieving a minimum value. These observations support the earlier experimental findings of Little and Whipkey (1979). At the optimum disk location, the vortices inside the cavity and behind the disk are spatially locked. It was also found that for cavity sizes slightly larger than the optimum even though the vortices are spatially locked the drag coefficient increases significantly. Entrainment of the main flow was observed to be greater into the smaller-than-optimum cavities. The reacting-flow calculations indicate that the dynamic vortices developed inside the cavity with the injection of fuel and air do not shed, even though the cavity size was determined based on cold-flow conditions. C1 Innovat Sci Solut Inc, Dayton, OH 45430 USA. USAF, Wright Lab, Wright Patterson AFB, OH 45433 USA. RP Katta, VR (reprint author), Innovat Sci Solut Inc, Dayton, OH 45430 USA. NR 13 TC 17 Z9 19 U1 1 U2 1 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 JAN PY 1998 VL 120 IS 1 BP 60 EP 68 DI 10.1115/1.2818088 PG 9 WC Engineering, Mechanical SC Engineering GA YV243 UT WOS:000071803700008 ER PT J AU Michalek, JE Rahe, AJ Kulkarni, PM Tripathi, RC AF Michalek, JE Rahe, AJ Kulkarni, PM Tripathi, RC TI Levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin in 1,302 unexposed Air Force Vietnam-era veterans SO JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY LA English DT Article ID OPERATION RANCH HAND; SERUM; WORKERS AB We summarize the distribution of 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) in 1,302 Air Force Veterans who serve as controls in a 20-year prospective epidemiologic study of health and exposure to herbicides and their dioxin contaminant in Air Force veterans of Operation Ranch Hand the unit responsible for aerial spraying of Agent Orange and other herbicides in Vietnam. We present statistics summarizing the dioxin distribution overall and by stratum of age and body mass index of these veterans. The average dioxin measurement was 4.23 and the standard deviation was 2.53 parts per trillion. With 95% confidence, 99% of the distribution is less than or equal to 10.4 parts per trillion. C1 Armstrong Lab, Brooks AFB, TX 78235 USA. RP Michalek, JE (reprint author), 2606 Doolittle Rd,Bldg 807, Brooks AFB, TX 78235 USA. EM joel.michalek@afhs.brooks.af.mil NR 10 TC 20 Z9 20 U1 0 U2 0 PU PRINCETON SCIENTIFIC PUBL INC PI PRINCETON PA PO BOX 2155, PRINCETON, NJ 08543 USA SN 1053-4245 J9 J EXPO ANAL ENV EPID JI J. Expo. Anal. Environ. Epidemiol. PD JAN-MAR PY 1998 VL 8 IS 1 BP 59 EP 64 PG 6 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA YT398 UT WOS:000071598900007 PM 9470105 ER PT J AU Hoshower, LM AF Hoshower, LM TI Forensic archeology and the need for flexible excavation strategies: A case study SO JOURNAL OF FORENSIC SCIENCES LA English DT Article DE forensic science; forensic archeology; forensic anthropology; Central Identification Laboratory Hawaii; recovery of human remains AB Anthropologists from the U.S. Army Central Identification Laboratory, Hawaii (CILHI) are routinely confronted with challenging situations when searching for the remains of American servicemen lost in armed conflicts. All CILHI anthropologists are well-versed and experienced in "textbook" archeological methods. As such, standard excavation techniques and procedures are the foundation for every CILHI recovery. Yet, the inherent nature of the CILHI missions prescribe excavation strategies that depart from those regularly presented in archeology textbooks. The unique nature and grand scale of the CILHI missions; environmental, physical, and geographic hazards; the salvage nature of the missions; time and budget constraints; and the inherent politically and emotionally charged atmospheres of the missions necessitate flexible excavation methods. For example, many CILHI recovery operations in Southeast Asia are excavations of large craters created by the impact of high-speed military aircraft in remote, unpopulated locales. In addition to rugged and dangerous terrain, an abundance of unexploded ordnance and poisonous reptiles and insects typically complicate excavations. These challenging circumstances dictate that the CILHI anthropologist constantly adapt conventional archeological techniques to unconventional excavation situations to maintain the crucial balance between maximum data recovery and scientific protocol. C1 USA, CILHI, Hickam AFB, HI 96853 USA. RP Hoshower, LM (reprint author), USA, CILHI, 310 Worchester Ave, Hickam AFB, HI 96853 USA. NR 9 TC 8 Z9 9 U1 1 U2 9 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0022-1198 J9 J FORENSIC SCI JI J. Forensic Sci. PD JAN PY 1998 VL 43 IS 1 BP 53 EP 56 PG 4 WC Medicine, Legal SC Legal Medicine GA YT598 UT WOS:000071623100009 PM 9456525 ER PT J AU Wolf, PJ Hunton, DE AF Wolf, PJ Hunton, DE TI Ionization mechanisms in CRRES chemical releases - 2. Strontium photoionization and Ba+/Sr+ collisional ionization cross-section calculations SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CRITICAL VELOCITY IONIZATION; BARIUM; SRO; SATELLITE; MISSION; CALCIUM; IONS; BAO AB Two particular collision processes involving electron transfer are investigated that may have impact on the analyses of ion flux data obtained in the CRRES G-1 and G-11b, upper atmospheric chemical release experiments. Ion pair production (sigma(IP)) and charge exchange ionization (sigma(CE)) cross sections are calculated as a function of collision energy for reactions between Ba/Sr atoms and O atoms and O+ ions, respectively, using two-state approximation theories. The cross sections for each process are calculated for both the ground and metastable states of the metal atoms. At a collision energy of 9.5 eV attained in the G-1 and G-11b CRRES releases, the calculations indicate that sigma(IP) = 1.3 x 10(-16) cm(2) and sigma(CE) = 2-6 x 10(-16) cm(2) for reactions involving Ba(S-1(0)). The cross sections for the analogous Sr reactions are approximately 1.2 x 10(-16) cm(2) and 2-8 x 10(-17) cm(2); respectively. In addition, Sr photoionization from P-3(J) metastable states is investigated. Although we calculate a 29-s photoionization time constant from these states, a kinetic analysis indicates the metastable states cannot accumulate an appreciable equilibrium population in full solar exposure. Thus photoionization from the Sr 3(J)(P) levels does not significantly contribute to the total ion inventory. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. Phillips Lab, Geophys Directorate, Space Charged Particle Effects Branch, Hanscom AFB, MA 01731 USA. RP Wolf, PJ (reprint author), USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. NR 38 TC 1 Z9 1 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JAN 1 PY 1998 VL 103 IS A1 BP 447 EP 455 DI 10.1029/97JA02040 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA YQ714 UT WOS:000071415900041 ER PT J AU Hunton, DE Wolf, PJ Shadid, TM AF Hunton, DE Wolf, PJ Shadid, TM TI Ionization mechanisms in CRRES chemical releases - 1. In situ measurements and model results SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID RADIATION EFFECTS SATELLITE; CRITICAL VELOCITY IONIZATION; BARIUM RELEASES; EXPANSION CHARACTERISTICS; STRONTIUM; PLASMA; SPACE; MISSION; CLOUDS; FIELD AB The quadrupole ion mass spectrometer (QIMS) measured fluxes of barium and strontium ions during the CRRES G-1 chemical release in full Sun and the G-11b release in darkness. The barium ion fluxes detected in darkness were only a factor of 10 lower than the photoionization fluxes: indicating that the rate of nonsolar-UV ionization was at least a factor of 8 higher than literature values of charge transfer and collisional ionization cross sections would suggest. Model calculations of the QIMS ion fluxes using new, state-specific, calculations of the cross sections for ion-pair formation and charge transfer [Wolf and Hunton, this issue] demonstrate that the large nonphotoionization rates are consistent with significant metastable excitation in the neutral cloud but not with a ground state population. Upper limits to the collisional ionization rates for the conditions of the releases are 4.3 x 10(-3) s(-1) for ion-pair production and 2.2 x 10(-3) s(-1) for charge transfer. Collisions of high-energy electrons with the neutrals early in the cloud expansion is suggested as a mechanism for producing the metastable metal atoms. A similar analysis of the strontium data indicates that photoionization, charge transfer, and collisional ion-pair production alone cannot explain the large fluxes of strontium ions detected in the sunlit release. Associative ionization may therefore be an important ionization mechanism for that metal in sunlight. The implications of these results for analysis of space critical ionization velocity experiments are discussed. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Hunton, DE (reprint author), USAF, Res Lab, Space Vehicles Directorate, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 43 TC 1 Z9 2 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JAN 1 PY 1998 VL 103 IS A1 BP 457 EP 470 DI 10.1029/97JA02344 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA YQ714 UT WOS:000071415900042 ER PT J AU Pericle, F Pinto, LA Hicks, S Kirken, RA Sconocchia, G Rusnak, J Dolan, MJ Shearer, GM Segal, DM AF Pericle, F Pinto, LA Hicks, S Kirken, RA Sconocchia, G Rusnak, J Dolan, MJ Shearer, GM Segal, DM TI Cutting edge: HIV-1 infection induces a selective reduction in STAT5 protein expression SO JOURNAL OF IMMUNOLOGY LA English DT Article ID IMMUNODEFICIENCY-VIRUS TYPE-1; TYROSINE PHOSPHORYLATION; SIGNAL-TRANSDUCTION; CELLS; TAT AB HIV-1 infection is accompanied by qualitative and quantitative defects in CD4(+) T lymphocytes, Loss of immune function in HIV patients is usually associated with a profound dysregulation of cytokine production. To investigate whether cytokine signaling defects occur during HIV infection, PHA blasts from healthy human donors were infected with two strains of HIV-1 and screened for the expression of STAT proteins used in cytokine signaling, A selective decrease in STAT5B was seen 8 days after infection with the BZ167 dual-tropic HIV isolate, but not with the Ba-L, M-tropic strain, Based on these findings, purified T cells from HIV-infected patients in different stages of disease were also tested for STAT expression; decreases in STAT5A, STAT5B, and STAT1 alpha were observed in all patients, The reduction in STATs seen in vivo and in vitro after HIV infection may contribute to the loss of T cell function in HIV disease. C1 NCI, Expt Immunol Branch, NIH, Bethesda, MD 20892 USA. NCI, Intramural Res Support Program, Sci Applicat Int Corp,Lab Mol Immunoregulat, Frederick Canc Res & Dev Ctr, Frederick, MD 21701 USA. Wilford Hall USAF Med Ctr, HIV Unit, Lackland AFB, TX 78236 USA. RP Segal, DM (reprint author), NCI, Expt Immunol Branch, NIH, Bldg 10,Room 4B17, Bethesda, MD 20892 USA. NR 31 TC 52 Z9 53 U1 0 U2 0 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD JAN 1 PY 1998 VL 160 IS 1 BP 28 EP 31 PG 4 WC Immunology SC Immunology GA YW266 UT WOS:000071915100007 PM 9551952 ER PT J AU Chiu, EK Jumper, JM Rockwell, BA Toth, CA AF Chiu, EK Jumper, JM Rockwell, BA Toth, CA TI Examination of pico- and femtosecond laser retinal lesions by electron microscopy. SO JOURNAL OF INVESTIGATIVE MEDICINE LA English DT Meeting Abstract C1 Duke Univ, Med Ctr, Durham, NC 27706 USA. Armstrong Lab, Brooks AFB, TX 78235 USA. RI toth, cynthia/F-5614-2011 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 JAN PY 1998 VL 46 IS 1 BP 74A EP 74A PG 1 WC Medicine, General & Internal; Medicine, Research & Experimental SC General & Internal Medicine; Research & Experimental Medicine GA YU124 UT WOS:000071684700389 ER PT J AU Rea, MA AF Rea, MA TI Neurochemical regulation of circadian phase SO JOURNAL OF NEUROCHEMISTRY LA English DT Meeting Abstract C1 AF Res Lab, Biol Rhythms & Integrat Neurosci Res Inst, San Antonio, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0022-3042 J9 J NEUROCHEM JI J. Neurochem. PY 1998 VL 70 SU 1 BP S44 EP S44 PG 1 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA YY627 UT WOS:000072167200174 ER PT J AU Ross, M Worrell, TW AF Ross, M Worrell, TW TI Thigh and calf girth following knee injury and surgery SO JOURNAL OF ORTHOPAEDIC & SPORTS PHYSICAL THERAPY LA English DT Article DE knee; surgery; thigh girth; calf girth ID CRUCIATE LIGAMENT TEAR; REFLEX INHIBITION; MUSCLE; RECONSTRUCTION; RELIABILITY; MORPHOLOGY AB Girth measures are commonly used to assess muscle atrophy or joint effusion, little is known, however, regarding girth measurement changes following knee injury and subsequent surgery. Therefore, the purpose of this study was to compare the thigh and calf girth measurements of involved and noninvolved extremities prior to and following knee surgery for subjects with acute and chronic knee injuries. Of the 40 subjects that were studied, 22 subjects were placed in the acute group (less than 6 months from time of injury to presurgery measurement) and 18 subjects were placed in the chronic group (greater than 6 months from rime of injury to presurgery measurement). Thigh and calif girth measurements were taken prior to surgery and then prior to the initiation of outpatient rehabilitation following surgery. For the acute and chronic groups, a three-way analysis of variance (ANOVA) with repeated measures on the extremity muscle, and rime factors was used to analyze the data. For each group, the three-way ANOVA revealed a significant two-way interaction between the extremity and lime factors. Post hoc analysis revealed significant differences between involved and noninvolved extremities at both the pie-and post-surgery time periods for the acute and chronic groups. While thigh and calf girth measurement differences existed between the involved and noninvolved extremities prior to and after surgery, the bulk of the girth measurement differences existed prior to surgery for both groups. Based upon the results of this study, the assessment and rehabilitation of the thigh and calf following knee injury and surgery are recommended. C1 96th Med Grp, Dept Phys Therapy, Elgin AFB, FL USA. Univ Indianapolis, Krannert Sch Phys Therapy, Indianapolis, IN 46227 USA. RP Ross, M (reprint author), 96th MSGS SGCPY, 307 Boatner Rd,Suite 114, Elgin AFB, FL 32542 USA. NR 22 TC 27 Z9 27 U1 1 U2 3 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0190-6011 J9 J ORTHOP SPORT PHYS JI J. Orthop. Sports Phys. Ther. PD JAN PY 1998 VL 27 IS 1 BP 9 EP 15 PG 7 WC Orthopedics; Rehabilitation; Sport Sciences SC Orthopedics; Rehabilitation; Sport Sciences GA YP199 UT WOS:000071252500003 PM 9440035 ER PT J AU Stefko, RM de Swart, RJ Dodgin, DA Wyatt, MP Kaufman, KR Sutherland, DH Chambers, HG AF Stefko, RM de Swart, RJ Dodgin, DA Wyatt, MP Kaufman, KR Sutherland, DH Chambers, HG TI Kinematic and kinetic analysis of distal derotational osteotomy of the leg in children with cerebral palsy SO JOURNAL OF PEDIATRIC ORTHOPAEDICS LA English DT Article DE ambulatory; cerebral palsy; derotation; gait analysis; osteotomy; tibial torsion ID TIBIAL TORSION; ROTATIONAL OSTEOTOMY; DEFORMITY; FIBULA; FOOT AB Patients with cerebral palsy often develop rotational deformities of the lower extremities. These deformities may be caused by abnormal muscle tone, soft-tissue contractures, or bony malalignment. When rotational deformity persists after correction of the soft-tissue components, bony-realignment procedures are warranted to improve gait in ambulatory patients. We performed a retrospective review of 10 ambulatory children with cerebral palsy and tibial torsion who underwent 13 distal tibial and fibular derotation osteotomies. Preoperative and postoperative three-dimensional gait analysis were used to determine the effect of distal tibial and fibular derotation osteotomy on tibial rotation, foot-progression angle, gait velocity, and moments about the ankle. Mean tibial rotation and foot-progression angle were significantly improved by the procedure. Gait velocity improved but not significantly. Moment data demonstrated a trend toward normal. This study demonstrates, that the derotational distal tibial and fibular osteotomy stabilized with percutaneous crossed Kirschner wires is a safe, reliable, and effective procedure for correcting rotational deformities of the leg in patients with cerebral palsy. C1 Wilford Hall USAF Med Ctr, Dept Orthopaed, PSSB, Lackland AFB, TX 78236 USA. RP Stefko, RM (reprint author), Wilford Hall USAF Med Ctr, Dept Orthopaed, PSSB, Lackland AFB, TX 78236 USA. OI Kaufman, Kenton/0000-0002-7311-3781 NR 28 TC 35 Z9 35 U1 2 U2 4 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0271-6798 J9 J PEDIATR ORTHOPED JI J. Pediatr. Orthop. PD JAN-FEB PY 1998 VL 18 IS 1 BP 81 EP 87 DI 10.1097/00004694-199801000-00016 PG 7 WC Orthopedics; Pediatrics SC Orthopedics; Pediatrics GA ZG845 UT WOS:000073045800016 PM 9449107 ER PT J AU Hsu, KY Goss, LP Roquemore, WM AF Hsu, KY Goss, LP Roquemore, WM TI Characteristics of a trapped-vortex combustor SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA 33rd Aerospace Sciences Meeting CY JAN 09-12, 1995 CL RENO, NEVADA SP Amer Inst Aeronaut & Astronaut ID FLOW AB Combustion characteristics are described for a conceptual combustor that utilizes a trapped vortex (TV) in a cavity to provide flame stability. The cavity is formed between two axisymmetric disks mounted in tandem, The upstream disk is referred to as the forebody, and the downstream disk is referred to as the afterbody. With coflowing annular air, a vortex is trapped in the cavity for certain geometries. Primary air and gaseous propane are injected directly into the cavity through multiple jets located on the upstream face of the afterbody. Particle-imaging-velocimetry measurements reveal that when the cavity length is 0.59 of the forebody diameter, a vortex is trapped in the cavity. Very low overall lean-blow-out equivalence ratios are obtained for the TV combustor over a wide range of annular- and primary-airflow rates. Temperature profiles obtained with a coherent-anti-Stokes-Raman-spectroscopy system show that as the primary-airflow rate increases (equivalence ratio approaches unity), the temperature in the vortex increases for a fixed fuel flow. An increase in the primary-airflow rate also results in a decrease in the name length. Peak combustion efficiency increases from 96.7 and 99% as the annular air is decreased, and to 98.8 and 99.8% when a second trapped vortex is added to the combustor via a second afterbody just downstream of the first afterbody. C1 Innovat Sci Solut Inc, Res, Dayton, OH 45440 USA. USAF, Wright Lab, Aeroprop & Power Directorate, Fuels & Lubricat Div, Wright Patterson AFB, OH 45433 USA. RP Hsu, KY (reprint author), Innovat Sci Solut Inc, Res, 2786 Indian Ripple Rd, Dayton, OH 45440 USA. NR 15 TC 74 Z9 97 U1 2 U2 12 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 JAN-FEB PY 1998 VL 14 IS 1 BP 57 EP 65 DI 10.2514/2.5266 PG 9 WC Engineering, Aerospace SC Engineering GA YR361 UT WOS:000071487700009 ER PT J AU Luker, JJ Hale, CS Bowersox, RDW AF Luker, JJ Hale, CS Bowersox, RDW TI Experimental analysis of the turbulent shear stresses for distorted supersonic boundary layers SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID CONCAVE SURFACE CURVATURE; SHORT REGIONS; DILATATION AB An experimental analysis of the turbulent shear stresses for a supersonic boundary lay er distorted by streamline curvature-induced pressure gradients was performed using laser Doppler velocimetry, Four pressure-gradient flows were examined: a nominally zero-pressure-gradient case (M = 2.8, Re-theta = 1.1 x 10(4), beta = 0.02); a favorable-pressure gradient (M = 2.9, Re-theta = 1.5 x 10(4), beta = -0.5); an adverse-pressure gradient (M = 2.7, Re-theta = 1.2 x 10(4), beta = 0.9); and a successive-pressure gradient (M = 2.5, Re-theta = 1.2 x 10(4), beta = -1.0, following a region of beta = 0.9). For the favorable-pressure gradient, the turbulent shear-stress levels across the boundary layer decreased by 70-100%, as compared to the zero-pressure-gradient boundary layer, Far the adverse-pressure gradient, a 70-100% increase was observed. For the combined-pressure gradient, the shear stresses returned to values similar to the zero-pressure-gradient flow. A new pressure gradient parameter was found to correlate well with the peak sheer-stress amplification, It was also postulated that the shear-stress amplifications were in part the result of the nonuniform hulk dilatation/compression and streamline divergence/convergence, implying a forcing phenomena that influenced the statistical <(u'v')over bar> correlation, The combined-pressure-gradient flow demonstrated that the turbulent structure adjusts relatively rapidly to the distortion, Numerical simulations of the mean velocity obtained with a kappa-omega turbulence model were found to agree very well with the present data, With the exception of the zero-pressure-gradient flow, the magnitudes of the turbulent shear stresses were not accurately reproduced; however, correct trends were predicted. C1 USAF, Inst Technol, Grad Sch Engn, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Luker, JJ (reprint author), USAF, Inst Technol, Grad Sch Engn, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 37 TC 2 Z9 2 U1 1 U2 1 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 JAN-FEB PY 1998 VL 14 IS 1 BP 110 EP 118 DI 10.2514/2.5256 PG 9 WC Engineering, Aerospace SC Engineering GA YR361 UT WOS:000071487700015 ER PT J AU Mollenhauer, DH Schaff, JR Rose, DH AF Mollenhauer, DH Schaff, JR Rose, DH TI Experimental verification of spline stress analysis method for a structural composite laminate containing a hole SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article AB Moire interferometry surface strain measurements for a uniaxially loaded composite laminate with an open hole were compared to predictions from three-dimensional spline variational theory, from two-dimensional finite element analysis, and from two-dimensional elasticity theory. Strain measurements and a progressive damage investigation were accomplished using twenty-eight ply fiber dominated, IM7/5250-4, laminates. At low load levels, prior to matrix cracking, phase shifting moire interferometry was used to measure in-plane displacements. Experimental surface strains were calculated based on digital analysis of the displacement fields. Direct comparisons between theory and experiment were made using contour plots of epsilon(xx), epsilon(yy), and gamma(xy). For all in-plane surface strains, the spline variational theory results showed good agreement with experiment in close proximity to the hole. A separate group of specimens were loaded incrementally until failure, and the initiation and progression of damage was documented using x-ray images. Regions where the stress exceeded the ultimate transverse strength are compared to the actual damage images using contour plotting schemes. Overall, the location of initial failure as predicted by the spline variational theory corresponded well with damage observations for early stages of damage. C1 United Technol Res Ctr, Struct Integr, E Hartford, CT 06108 USA. IIT Res Inst, Rome, NY USA. USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH USA. RP Schaff, JR (reprint author), United Technol Res Ctr, Struct Integr, MS 129-73,411 Silver Lane, E Hartford, CT 06108 USA. NR 16 TC 3 Z9 3 U1 0 U2 0 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1998 VL 17 IS 2 BP 96 EP 108 PG 13 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA YY399 UT WOS:000072143200001 ER PT J AU Kwon, YW Baron, DT AF Kwon, YW Baron, DT TI Numerical predictions of progressive damage evolution in particulate composites SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article ID FIBROUS COMPOSITES; BEHAVIOR; MODULI; MODEL AB A method is presented for calculating stresses and strains in a loaded particulate composite structure (specimen) as damage initiates and grows. Load is incrementally applied to a numerically simulated specimen. For every load increment, a finite element method model is used to calculate the composite stresses and strains at each point. A micromechanical model uses the composite strains to calculate the stresses and strains in the composite's component materials, the particles and matrix. A damage model uses the matrix strains to determine values for local matrix damage, and to set reductions in the stiffnesses of damaged matrix material regions, each of which is proportional to the associated damage value. At damaged locations, the micromechanical model uses the reduced matrix stiffnesses to calculate reduced composite stiffnesses. All reduced matrix and composite stiffnesses calculated during a load increment are used in the next load increment. Matrix strain values are set which determine damage initiation, growth, and saturation. Damage saturation indicates matrix material failure, and for saturation the composite stiffness approaches zero. At a specimen point a matrix crack will form or extend when the point becomes saturated with damage. Numerical simulation predictions are presented, and compared to experimental data. Plots are included showing stress and strain variation, and crack growth. C1 USAF, Res Lab, Raytheon STX Corp, Edwards AFB, CA 93524 USA. USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. RP Baron, DT (reprint author), USAF, Res Lab, Raytheon STX Corp, Edwards AFB, CA 93524 USA. NR 16 TC 3 Z9 3 U1 0 U2 0 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1998 VL 17 IS 8 BP 691 EP 711 PG 21 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA ZP710 UT WOS:000073780700002 ER PT J AU Calcaterra, JR Mall, S AF Calcaterra, JR Mall, S TI Investigation of the fatigue behavior of SCS-Ultra/Ti-6-4 SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article DE fatigue; elevated temperature; metal matrix composite; silicon carbide; titanium AB The focus of this study is to evaluate the fatigue behavior of SCS-Ultra/Ti-6-4 at 427 degrees C. The improvement in ultimate strength over SCS-6/Ti-6-4 was less than expected and the fatigue lives of the new material were much shorter at all stress levels. Posttest evaluation with a scanning electron microscope revealed several processing flaws in the new composites. Because of these flaws, the SCS-Ultra fibers failed at a lower composite stress than predicted and there were numerous crack initiation sites to greatly accelerate the progression of damage in fatigue tests. Despite the poor fatigue performance of the SCS-Ultra/Ti-6-4 specimens, this material shows promise for greatly increased ultimate strength. Both the stress and strain to failure are greater than SCS-6/Ti-6-4, even with the previously mentioned processing defects. C1 USAF, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, AFIT ENY Bldg 640,2950 P St, Wright Patterson AFB, OH 45433 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1998 VL 17 IS 13 BP 1202 EP 1212 PG 11 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 110ZZ UT WOS:000075414000005 ER PT J AU Roux, JA Vaughan, JG Shanku, R Arafat, ES Bruce, JL Johnson, VR AF Roux, JA Vaughan, JG Shanku, R Arafat, ES Bruce, JL Johnson, VR TI Comparison of measurements and modeling for pultrusion of a fiberglass/epoxy I-beam SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article DE pultrusion; fiberglass/epoxy; manufacturing modeling; measurements AB This research presents the experimental characterization and modeling of three-dimensional unsteady-state temperature and degree of cure distributions for the pultrusion manufacturing of fiberglass-epoxy I-beam composites. The model is capable of predicting temperature and degree of cure distributions for composites with Cartesian shapes in three dimensions and temperature profiles in pultrusion dies without the aid of predetermined temperature values used as die wall boundary conditions. The numerical model is compared with experimentally measured temperatures and degrees of cure recorded during the actual pultrusion manufacturing of the fiberglass-epoxy I-beams. Using a differential scanning calorimeter (DSC), the die composite exit degree of cure was also obtained. The finite volume method was utilized in the development of the numerical model for solving the governing energy and species equations used in modeling the entire heating section of the pultruder. The combinations of pull speed, fiber volume, and die temperature profiles can be modeled very economically to simulate pultrusion manufacturing of composites. Since this research is not limited in terms of predetermined temperature values, it can be tailored easily to predict a multitude of temperature profiles suited for st pultrusion process. This research is also important because it provides realistic modeling of irregular cross-sectional geometries. C1 Univ Mississippi, Dept Mech Engn, University, MS 38677 USA. Rust Coll, Holly Springs, MS 38635 USA. USAF, Wright Lab, Mfg Technol Directorate, Wright Patterson AFB, OH 45433 USA. RP Roux, JA (reprint author), Univ Mississippi, Dept Mech Engn, University, MS 38677 USA. NR 7 TC 13 Z9 13 U1 0 U2 4 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1998 VL 17 IS 17 BP 1557 EP 1579 PG 23 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 125TJ UT WOS:000076252900005 ER PT J AU Weisman, WH AF Weisman, WH TI Total petroleum hydrocarbon criteria working group: A risk-based approach for the management of total petroleum hydrocarbons in soil SO JOURNAL OF SOIL CONTAMINATION LA English DT Editorial Material DE petroleum hydrocarbons; petroleum contaminated; petroleum mixtures AB This document describes the technical strategy used by the TPH Criteria Working Group to develop its risk-based approach for establishing soil cleanup levels at petroleum contaminated sites. The Working Group relied on best data available in the published and unpublished literature for physical, chemical, and toxicological characteristics of petroleum mixtures in the environment. The Working Group's approach, culminating in the derivation of fate and transport fraction toxicity criteria, represents a scientifically sound technical basis for risk-based corrective action at petroleum contaminated sites. While the approach does not address ecological risk or aesthetic criteria, the strategy for developing the Working Group approach can be modified to address these concerns. This document provides a quick overview of the Working Group technical efforts and an introduction for the detailed technical documents completed to document these efforts. C1 OL, AL, HSC, OET, Wright Patterson AFB, OH 45433 USA. RP Weisman, WH (reprint author), OL, AL, HSC, OET, 2856 G St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 16 Z9 17 U1 1 U2 11 PU CRC PRESS INC PI BOCA RATON PA 2000 CORPORATE BLVD NW, JOURNALS CUSTOMER SERVICE, BOCA RATON, FL 33431 USA SN 1058-8337 J9 J SOIL CONTAM JI J. Soil Contam. PY 1998 VL 7 IS 1 BP 1 EP 15 PG 15 WC Environmental Sciences SC Environmental Sciences & Ecology GA YW511 UT WOS:000071943100001 ER PT J AU Neta, B Vallado, D AF Neta, B Vallado, D TI On satellite umbra/penumbra entry and exit positions SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article AB The problem of computing Earth satellite entry and exit positions through the Earth's umbra and penumbra, for satellites in elliptical orbits, is solved without the use of a quartic equation. A condition for existence of a solution in the case of a cylindrical shadow is given. This problem is of interest in case one would like to include perturbation force resulting from solar radiation pressure. Most satellites (including geosynchronous) experience periodic eclipses behind the Earth. Of course when the satellite is eclipsed, it's not exposed to solar radiation pressure. When we need extreme accuracy, we must develop models that turn the solar radiation calculations "on" and "off," as appropriate, to account for these periods of inactivity. C1 USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. RP Neta, B (reprint author), USN, Postgrad Sch, Dept Math, Code MA ND, Monterey, CA 93943 USA. RI Neta, Beny/B-1737-2009 NR 9 TC 11 Z9 12 U1 0 U2 0 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD JAN-MAR PY 1998 VL 46 IS 1 BP 91 EP 103 PG 13 WC Engineering, Aerospace SC Engineering GA 152BH UT WOS:000077755200006 ER PT J AU Matson, CL AF Matson, CL TI Resolution, linear filtering, and positivity SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID STABILIZED RECONSTRUCTION; SUPPORT CONSTRAINTS; INVERSE PROBLEMS; ERROR REDUCTION; SUPERRESOLUTION; IMAGE; EXTRAPOLATION; RESTORATION; ALGORITHM; SIGNAL AB Ultimately, the band-limited nature of imaging systems restricts image quality in measured data. However, prior knowledge can be employed to improve image quality beyond that available from measured data. Kinds of prior knowledge include knowledge of the support of the object and knowledge that the object has only positive intensities. In previous work it has been shown that prior knowledge increases image quality by two means: superresolution and improvements in the signal-to-noise ratio in the Fourier domain. However after prior knowledge is enforced, the resulting filter that multiplies the Fourier data may unduly limit resolution in the constrained image. Here maximum achievable resolutions are derived for one-and two-maximum achievable resolution by as much as a factor of 2. As a result, algorithms that use positivity to improve the quality of Fourier-domain data may benefit from a final postprocessing step to increase resolution. (C) 1998 Optical Society of America. C1 USAF, Phillips Lab, Opt Sensing Div, Kirtland AFB, NM 87117 USA. RP Matson, CL (reprint author), USAF, Phillips Lab, Opt Sensing Div, Kirtland AFB, NM 87117 USA. NR 22 TC 6 Z9 6 U1 0 U2 0 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 JAN PY 1998 VL 15 IS 1 BP 33 EP 41 DI 10.1364/JOSAA.15.000033 PG 9 WC Optics SC Optics GA YQ744 UT WOS:000071418900004 ER PT J AU Milonni, PW Fugate, RQ Telle, JM AF Milonni, PW Fugate, RQ Telle, JM TI Analysis of measured photon returns from sodium beacons SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID LASER-GUIDE-STAR; ADAPTIVE-OPTICS; MESOSPHERIC SODIUM; PERFORMANCE; ASTRONOMY; LAYER; EXCITATION; TELESCOPES; FREQUENCY; SYSTEMS AB We describe an approach to the computation of photon returns from mesospheric sodium beacons excited by laser pulse trains and discuss as specific examples the required numbers of photons for adaptive-optical compensation of atmospheric turbulence. Computed photon return signals are compared with reported measurements for pulses that are long, short, or comparable to the D-2 radiative lifetime (16 ns). Analytical approximations in good agreement with the numerical computations are derived. The results are consistent with experimental data for the different pulse durations. (C) 1998 Optical Society of America. C1 Univ Calif Los Alamos Natl Lab, Atom & Opt Theory Grp T 4, Los Alamos, NM 87545 USA. USAF, Res Lab, Starfire Opt Range, Kirtland AFB, NM 87117 USA. RP Milonni, PW (reprint author), Univ Calif Los Alamos Natl Lab, Atom & Opt Theory Grp T 4, POB 1663, Los Alamos, NM 87545 USA. NR 38 TC 46 Z9 47 U1 2 U2 8 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 JAN PY 1998 VL 15 IS 1 BP 217 EP 233 DI 10.1364/JOSAA.15.000217 PG 17 WC Optics SC Optics GA YQ744 UT WOS:000071418900023 ER PT J AU Teichman, JMH Vassar, GJ Bishoff, JT Bellman, GC AF Teichman, JMH Vassar, GJ Bishoff, JT Bellman, GC TI Holmium:YAG lithotripsy yields smaller fragments than lithoclast, pulsed dye laser or electrohydraulic lithotripsy SO JOURNAL OF UROLOGY LA English DT Article DE urinary calculi; lithotripsy; lithotripsy, laser; holmium ID IN-VITRO; DISINTEGRATION; ABLATION; CALCULI; TISSUE AB Purpose: The mechanism of lithotripsy differs among electrohydraulic Lithotripsy, mechanical lithotripsy, pulsed dye lasers and holmium:YAG lithotripsy. It is postulated that fragment size fl om each of these lithotrites might also differ. This study tests the hypothesis that holmium:YAG lithotripsy yields the smallest fragments among these lithotrites. Materials and Methods: We tested 3F electrohydraulic lithotripsy, 2 mm. mechanical lithetripsy, 320 mu m. pulsed dye lasers and 365 mu m. holmium:YAG fiber on stones composed of calcium hydrogen phosphate dihydrate, calcium oxalate monohydrate, cystine, magnesium ammonium phosphate and uric acid. Fragments were dessicated and sorted by size. Fragment size distribution was compared among lithotrites for each composition. Results: Holmium:YAG fragments were significantly smaller on average than fragments from the other lithotrites for all compositions. There were no holmium:YAG fragments greater than 4 mm., whereas there were for the other lithotrites. Holmium:YAG had significantly greater weight of fragments less than 1 mm. compared to the other lithotrites. Conclusions: Holmium:YAG yields smaller fragments compared to electrohydraulic lithotripsy, mechanical lithotripsy or pulsed dye lasers. These findings imply that fragments from holmium:YAG lithotripsy are more likely to pass without problem compared to the other lithetrites. Furthermore, the significant difference in fragment size adds evidence that holmium:YAG lithotripsy involves vaporization. C1 WILFORD HALL USAF MED CTR, LACKLAND AFB, TX 78236 USA. SO CALIF PERMANENTE MED GRP, LOS ANGELES, CA 90027 USA. RP UNIV TEXAS, HLTH SCI CTR, DIV UROL, 7703 FLOYD CURL DR, SAN ANTONIO, TX 78284 USA. NR 19 TC 129 Z9 139 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0022-5347 EI 1527-3792 J9 J UROLOGY JI J. Urol. PD JAN PY 1998 VL 159 IS 1 BP 17 EP 23 DI 10.1016/S0022-5347(01)63998-3 PG 7 WC Urology & Nephrology SC Urology & Nephrology GA YK232 UT WOS:A1998YK23200005 PM 9400428 ER PT J AU Cross, CA English, SF Cespedes, RD McGuire, EJ AF Cross, CA English, SF Cespedes, RD McGuire, EJ TI A followup on transurethral collagen injection therapy for urinary incontinence SO JOURNAL OF UROLOGY LA English DT Article DE urinary incontinence, stress; collagen; urinary tract; urination disorders ID CROSS-LINKED COLLAGEN; PERIURETHRAL IMPLANTATION; WOMEN AB Purpose: Transurethral collagen injection therapy has been used successfully in treating stress urinary incontinence due to intrinsic sphincter deficiency since United States Food and Drug Administration approval in October 1993, Materials and Methods: Telephone interview and chart review were performed on 139 women with intrinsic sphincter deficiency documented using video urodynamics, of whom 73% had grade 3 incontinence (leakage without effort). Median followup was 18 months (range 6 to 36). Median patient age was 72 years. Results: A total of 103 patients (74%) was substantially improved after collagen therapy, 29 (20%) were improved and 7 had no improvement. Of the substantially improved group 72% obtained continence after 2 or fewer injections. Of the patients 11% required a ''booster Injection more than 6 months after initial treatment. Complications, such as hematuria, urinary tract infections or transient urinary retention, were rare. Conclusions: Our results confirm the safety and efficacy of transurethral collagen. Once continence is achieved further collagen therapy is rarely necessary. C1 UNIV TEXAS, SCH MED, DIV UROL, HOUSTON, TX USA. WILFORD HALL USAF MED CTR, PSSU, DEPT UROL, LACKLAND AFB, TX USA. RP UNIV TEXAS, SCH MED, DEPT OBSTET GYNECOL & REPROD MED, HOUSTON, TX USA. NR 17 TC 35 Z9 38 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0022-5347 EI 1527-3792 J9 J UROLOGY JI J. Urol. PD JAN PY 1998 VL 159 IS 1 BP 106 EP 108 DI 10.1016/S0022-5347(01)64027-8 PG 3 WC Urology & Nephrology SC Urology & Nephrology GA YK232 UT WOS:A1998YK23200034 PM 9400447 ER PT J AU Makabe, T Garscadden, A AF Makabe, T Garscadden, A TI Papers from the International Workshop on Basic Aspects of Nonequilibrium Plasmas Interacting with Surfaces (BANPIS '97) - 26-27 January 1997, Nanki Seaside Lodge Shirahama, Wakayama, Japan - Preface SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Editorial Material C1 Keio Univ, Tokyo 108, Japan. AFRL, Wright Patterson AFB, OH USA. RP Makabe, T (reprint author), Keio Univ, Tokyo 108, Japan. NR 0 TC 0 Z9 0 U1 0 U2 0 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 JAN-FEB PY 1998 VL 16 IS 1 BP 215 EP 215 PG 1 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA YT383 UT WOS:000071597100034 ER PT J AU Convertino, VA AF Convertino, VA TI Interaction of semicircular canal stimulation with carotid baroreceptor reflex control of heart rate SO JOURNAL OF VESTIBULAR RESEARCH-EQUILIBRIUM & ORIENTATION LA English DT Review DE vestibular function; autonomic function; heart rate; baroreflex ID CARDIAC REFLEX; ORTHOSTATIC INTOLERANCE; BAROREFLEX RESPONSES; VAGAL BAROREFLEX; EXERCISE; PRESSURE; HYPOTENSION; TOLERANCE; VOLUME; HUMANS AB The carotid-cardiac baroreflex contributes to the prediction of orthostatic tolerance; experimental attenuation of the reflex response leads to orthostatic hypotension in humans and animals, Anecdotal observations indicate that rotational head movements about the vertical axis of the body can also induce orthostatic bradycardia and hypotension through increased parasympathetic activity, We therefore measured the chronotropic response to carotid baroreceptor stimulation in 12 men during varying conditions of vestibulo-oculomotor stimulation to test the hypothesis that stimulation of the semicircular canals associated ,vith head movements in the yaw plane inhibits cardioacceleration through a vagally mediated baroreflex. Carotid-cardiac baroreflex response was assessed by plotting R-R intervals (ms) at each of 8 neck pressure steps with their respective carotid distending pressures (mmHg), Calculated baroreflex gain (maximal slope of the stimulus-response relationship) was measured under 4 experimental conditions: 1) sinusoidal whole-body yaw rotation of the subject in the dark without visual: fixation (combined vestibular-oculomotor stimulation); 2) yaw oscillation of the subject while tracking a small head-fixed light moving with the subject (vestibular stimulation without eye movements); 3) subject stationary while fixating on a small light oscillating in yaw at the same frequency, peak acceleration, and velocity as the chair (eye movements without vestibular stimulation); and 4) subject stationary in the dark (no eye or head motion), Head motion alone and with eye movement reduced baseline baroreflex responsiveness to the same stimulus by 30%, Inhibition of cardioacceleration during rotational head movements may have significant impact on functional performance in aerospace environments, particularly in high-performance aircraft pilots during high angular acceleration in aerial combat maneuvers or in astronauts upon return from spaceflight who already have attenuated baroreflex functions, Published by Elsevier Science Inc. RP Convertino, VA (reprint author), ARMSTRONG LAB, AOCY, DIV CLIN SCI, PHYSIOL RES BRANCH, 2507 KENNEDY CIRCLE, BROOKS AFB, TX 78235 USA. NR 29 TC 16 Z9 16 U1 0 U2 1 PU IOS PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 0957-4271 J9 J VESTIBUL RES-EQUIL JI J. Vestib. Res.-Equilib. Orientat. PD JAN-FEB PY 1998 VL 8 IS 1 BP 43 EP 49 PG 7 WC Neurosciences; Otorhinolaryngology SC Neurosciences & Neurology; Otorhinolaryngology GA YL340 UT WOS:A1998YL34000006 PM 9416588 ER PT J AU Libby, A O'Connell, P Allred, DC AF Libby, A O'Connell, P Allred, DC TI Lobular carcinoma in situ: Biologic features including loss of heterozygosity. SO LABORATORY INVESTIGATION LA English DT Meeting Abstract C1 Univ Texas, Hlth Sci Ctr, San Antonio, TX 78285 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0023-6837 J9 LAB INVEST JI Lab. Invest. PD JAN PY 1998 VL 78 IS 1 MA 112 BP 22A EP 22A PG 1 WC Medicine, Research & Experimental; Pathology SC Research & Experimental Medicine; Pathology GA YU933 UT WOS:000071771200127 ER PT J AU Libby, A Hilsenbeck, SG Elledge, RM Allred, DC AF Libby, A Hilsenbeck, SG Elledge, RM Allred, DC TI Biologic characteristics of special-type (ST) compared to no-special-type (NST) invasive breast cancers. SO LABORATORY INVESTIGATION LA English DT Meeting Abstract C1 Univ Texas, Hlth Sci Ctr, San Antonio, TX 78285 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0023-6837 J9 LAB INVEST JI Lab. Invest. PD JAN PY 1998 VL 78 IS 1 MA 113 BP 23A EP 23A PG 1 WC Medicine, Research & Experimental; Pathology SC Research & Experimental Medicine; Pathology GA YU933 UT WOS:000071771200128 ER PT S AU Camden, MP Simmons, LW AF Camden, MP Simmons, LW BE Pryputniewicz, RJ Brown, GM Juptner, WPO TI Using a laser vibrometer for monitoring dynamic strain, modal analysis and calculating damping SO LASER INTERFEROMETRY IX: APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Interferometry IX - Native and Artificial CY JUL 22-23, 1998 CL SAN DIEGO, CA SP SPIE, Int Soc Opt Engn DE laser vibrometer; dynamic strain; modal analysis; damping; optical instrumentation AB With the renewed interest in hypervelocity vehicles, component testing in extreme thermoacoustic and thermovibration environments is now required. This requires new test facilities and new instrumentation techniques be developed to test and evaluate these new structures, components and sub-components. To collect data in these extreme environments new instrumentation is needed. In a dynamic test environment use of strain gages is limited to low temperature testing. This paper describes how room temperature and high temperature (>2000 degrees F) strain data is collected, using a laser vibrometer, on cantilevered coupons. This paper also describes the use of a laser vibrometer to obtain mode shapes and damping information. With new structural components, many manufactured from new composite materials such as ceramic matrix composites (CMC), there is a need to acquire accurate mode shapes and damping information. Traditionally modal analysis is done using accelerometers to map out the responses of a structure. This is time consuming, expensive and on small structures the weight of the accelerometers could affect the results. Through the use of a laser vibrometer accurate mode shapes can be obtained quickly. This information can be used to validate finite element models and to determine instrumentation locations on test components. With complex structures it is essential to determine the correct locations to install instrumentation when performing high level dynamic testing, the vibrometer is ideally suited for this. While the mode shapes are being mapped using a vibrometer it is an easy and logical step to calculate the damping of the structural component. Damping is calculated using the half-power bandwidth method that provides accurate results when using a vibrometer. C1 USAF, Res Lab, Air Vehicles Directorate, Struct Div, Wright Patterson AFB, OH 45433 USA. RP Camden, MP (reprint author), USAF, Res Lab, Air Vehicles Directorate, Struct Div, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2934-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3479 BP 311 EP 318 DI 10.1117/12.316462 PG 8 WC Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BM33D UT WOS:000078399900035 ER PT S AU McManamon, PF AF McManamon, PF BE Kamerman, GW TI Laser radar development SO LASER RADAR TECHNOLOGY AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Laser Radar Technology and Applications III CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE sensing; affordable sensing; multifunction sensing; multifunction EO; multidiscriminant sensing; modular sensors; laser radar; ladar; lidar; multidiscriminant laser radar AB This paper discusses the trends in laser radar development. Applications include reconnaissance and targeting from airborne and spaceborne platforms. A multifunction airborne sensor system, which includes a laser radar function with many modes, is defined. A multidiscriminant space borne laser radar is also described and its feasibility is assessed. A number proposed and existing Air Force programs to develop laser radar technology are described. C1 AFRL, SNJ, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP McManamon, PF (reprint author), AFRL, SNJ, Sensors Directorate, Bldg 620,2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 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 0-8194-2829-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3380 BP 50 EP 57 DI 10.1117/12.327178 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BL68V UT WOS:000076320100006 ER PT S AU Gregg, M Bossert, D Gallant, D McMackin, I Marciante, J Wright, M AF Gregg, M Bossert, D Gallant, D McMackin, I Marciante, J Wright, M BE Kamerman, GW TI Semiconductor and fiber laser development at air force research laboratory directed energy directorate SO LASER RADAR TECHNOLOGY AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Laser Radar Technology and Applications III CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE diode laser; fiber laser; filamentation; injection locking AB This paper will review Air Force Research Laboratory Directed Energy Directorate (AFRL/DE) development programs which provide high-efficiency electric semiconductor diode lasers and diode pumped fiber lasers for a host of applications including free space communications, laser radar, illuminators, trackers and designators. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Gregg, M (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-2829-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3380 BP 80 EP 87 DI 10.1117/12.327183 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BL68V UT WOS:000076320100011 ER PT S AU Mosley, DE Matson, CL Czyzak, SR AF Mosley, DE Matson, CL Czyzak, SR BE Kamerman, GW TI Applications of the HI-CLASS (High Performance CO2 Laser Radar Surveillance Sensor) laser system for active imaging of space objects SO LASER RADAR TECHNOLOGY AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Laser Radar Technology and Applications III CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE AB The HI-CLASS is a high power, wideband, coherent laser radar (ladar) for long range detection, tracking and imaging located at the Maul Space Surveillance Site. HI-CLASS will be used to provide high precision metrics as well as information for images of space objects and remote sensing with the same system. The four phases of the HI-CLASS hardware development program were completed in Fall 1997. During this development contract, hardware and software were developed for two different modes of operation; a ladar mode for active imaging of satellites, and a lidar mode for remote sensing atmospheric measurements. Throughout the contract, data were collected which provided a demonstration of the system capabilities which validated technology and designs required for fielding operational systems. The HI-CLASS follow-on demonstration program is currently being performed under an Air Force contract. The follow-on demonstrations will provide the groundwork to an upgrade program currently under consideration by the Air Force. HI-CLASS provides high accuracy tracking in position and velocity simultaneously, and by ultimately providing size, shape and orientation information, it will help assess adversary capabilities. HI-CLASS has the potential to address operational areas of need for increased capability for information about space objects. The follow-on contract effort and the HI-CLASS upgrade effort will provide a demonstration of these potential applications of the HI-CLASS system. C1 USAF, Res Lab, Surveillance Technol Branch, DEBS, Kirtland AFB, NM 87117 USA. RP Mosley, DE (reprint author), USAF, Res Lab, Surveillance Technol Branch, DEBS, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-2829-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3380 BP 243 EP 249 DI 10.1117/12.327197 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BL68V UT WOS:000076320100025 ER PT S AU Grantham, JW Meidunas, EC AF Grantham, JW Meidunas, EC BE Kamerman, GW TI Laser radar in adverse weather SO LASER RADAR TECHNOLOGY AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Laser Radar Technology and Applications III CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE laser radar; LADAR; laser propagation; adverse weather; dropouts; false returns AB Laser radar images of an outdoor target scene were collected in adverse weather such as rain and fog during the course of one year. Included in this collection is imagery in fogs with visibilities less than 2 km and rains with rain rates of up to 60 mm/hr. The targets were calibrated panels at 510 m and 1 km. The laser radar system used was a direct-detection 1.06 mu m system designed to operate at 2 km in clear weather. For the purposes described here, though, the maximum range gate was set to 1.5 km. The system used a correlation technique for detection and discrimination, which significantly reduced the number of false returns in fog. Using these collected images, dropout pixels and false returns were correlated with rain rate and visibility. Extinction coefficients for 1.064 mu m laser light were also calculated as a function of rain rate and visibility in fog and rain conditions. These coefficients were found to be consistent with those measured previously at 0.55 mu m, 0.63 mu m and 10.6 mu m. These coefficients can be used to predict the performance of any circular polarized 1.064 um LADAR system in rain and fog conditions. C1 USAF, Res Lab, Munit Directorate, Adv Guidance Div, Washington, DC 20330 USA. RP Grantham, JW (reprint author), USAF, Res Lab, Munit Directorate, Adv Guidance Div, Washington, DC 20330 USA. NR 0 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 0-8194-2829-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3380 BP 303 EP 314 DI 10.1117/12.327203 PG 12 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BL68V UT WOS:000076320100032 ER PT S AU Payne, DJ Hopkins, RA Eilert, B Noojin, GD Rockwell, BA AF Payne, DJ Hopkins, RA Eilert, B Noojin, GD Rockwell, BA BE Jacques, SL Katzir, A TI Threshold energies in the artificial retina SO LASER-TISSUE INTERACTION IX. PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction IX CY JAN 26-28, 1998 CL SAN JOSE, CA SP USAF Off Sci Res, Int Biomed Opt Soc, Soc Photo Opt Instrumentat Engineers DE laser; ultrashort; threshold; retina; damage AB Laser threshold energies for artificial retinal damage from ultrashort (i.e. less than or equal to 1 ns) laser pulses are investigated as a function of both pulse width and spot size. A piece of film acts as the absorbing layer and is positioned at the focus of the Cain artificial eye(1) (17 mm in water). We performed experiments at the focal point, and at two and ten Rayleigh ranges in front of the focus with the damage endpoint being the presence of a bubble coming off the film. Thresholds were determined for wavelengths of 1064 nm, 580 mn, and 532 nm with pulse durations ranging from the nanosecond (ns) to the femtosecond (fs) regimes. For the at-focus data in the visible regime, the threshold dropped from 0.25 mu J for a 5 ns pulse at 532 nm to 0.11 mu J for a 100 fs, 580 nm pulse. Similarly, for the near infrared (NIR) the threshold changed from 5.5 mu J for a 5 ns pulse to 0.9 mu J for a 130 fs pulse. These results are discussed in the context of applicable nonlinear optical phenomena. C1 USAF, Res Lab, Human Effectiveness Directorate, Directed Energy Bioeffects Div,Opt Radiat Branch, Brooks AFB, TX 78235 USA. RP Payne, DJ (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Directed Energy Bioeffects Div,Opt Radiat Branch, 8111 18th St, Brooks AFB, TX 78235 USA. NR 0 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 0-8194-2693-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3254 BP 130 EP 134 DI 10.1117/12.308157 PG 5 WC Engineering, Biomedical; Optics SC Engineering; Optics GA BL09D UT WOS:000074238700018 ER PT S AU Kennedy, PK Druessel, JJ Cupello, JM Till, S Gerstman, BS Thompson, CR Rockwell, BA AF Kennedy, PK Druessel, JJ Cupello, JM Till, S Gerstman, BS Thompson, CR Rockwell, BA BE Jacques, SL Katzir, A TI Parameter sensitivity of the Thompson granular retinal damage model SO LASER-TISSUE INTERACTION IX. PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction IX CY JAN 26-28, 1998 CL SAN JOSE, CA SP USAF Off Sci Res, Int Biomed Opt Soc, Soc Photo Opt Instrumentat Engineers DE lasers; retinal damage; photothermal damage; granular model; parameter sensitivity; design of experiments AB As part of a research program to understand and model eye damage produced by exposure to cw and pulsed lasers, the U.S. Air Force has created a granular model of laser retinal damage. The Thompson granular model simulates absorption of light by melanosomes distributed in the retinal pigmented epithelium, melanosome heating, and subsequent photothermal damage from bulk tissue heating. Various biological input parameters required for the model, such as the density, size, spatial distribution, and absorption coefficient of melanosomes, are not well, known, creating uncertainty in the results. This problem is being addressed both experimentally, through measurements of biological parameters for various species, and theoretically, through analysis of parameter sensitivity in the model. In the current study, the parameter sensitivity was analyzed using a technique known as "design of experiments," which allows statistical estimation of the relative importance of independent experimental variables. A matrix of 20 cases has been analyzed, using 7 input parameters as independent variables. Cases have been confined to the long pulse regime (greater than or equal to 10 mu s), where photothermal damage is dominant. Results were assessed using both temperature rise and Arrhenius damage integral values. Corneal fluence was found to be the most important physical parameter and melanosome absorption the most important biological parameter. C1 USAF, Res Lab, Opt Radiat Branch, Brooks AFB, TX 78235 USA. RP Kennedy, PK (reprint author), USAF, Res Lab, Opt Radiat Branch, Brooks AFB, TX 78235 USA. NR 0 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 0-8194-2693-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3254 BP 146 EP 155 DI 10.1117/12.308160 PG 10 WC Engineering, Biomedical; Optics SC Engineering; Optics GA BL09D UT WOS:000074238700020 ER PT J AU Ricci, RM Finley, EM Grimwood, RE AF Ricci, RM Finley, EM Grimwood, RE TI Treatment of cutaneous hemangiomas in preterm neonatal twins with the flashlamp-pumped pulsed dye laser SO LASERS IN SURGERY AND MEDICINE LA English DT Article DE involution; regression; ulcerated hemangioma; nasal hemangioma; youngest ID VASCULAR-LESIONS AB Background and Objective: We report two cases of hemangiomas in twins born at a gestational age of 30 weeks who were treated with a flashlamp-pumped pulsed dye laser (FPDL) at 40 days postpartem. These were the youngest patients to our knowledge to be treated with FPDL. Study Design/Patients and Methods: Twin Caucasian females were born 10 weeks preterm. Twin A soon developed a 1 cm blanching erythematous patch with telangiectasia on a slightly bulbous nasal tip. Twin B developed a 6 mm erythematous papule on her forehead, a 12 x 10 cm erythematous plaque on her left shoulder, and two plaques measuring 2.5 x 2.0 cm and 1.5 x 1.0 cm on her right hip. The twins received seven monthly laser treatments. Results: Several of the hemangiomas showed remarkable regression, including the lesions which became ulcerated and healed on Twin B's left shoulder and right hip. No general or topical anesthesia was used and the twins tolerated the procedure well. No significant adverse effects were encountered. The maximum single treatment dose was 7 mm spot size, 5.0 J/cm2 and 186 pulses for twin B and 6.25 J/cm2 and 16 pulses for twin A. Conclusion: To our knowledge, our patients are the youngest reported to be treated with FPDL at age 30 days preterm. Some of their hemangiomas responded, and no significant adverse effects were encountered. More prospective trials are needed to determine whether early treatment with FPDL accelerates regression of hemangiomas or results in a better cosmetic outcome than expectant treatment. (C) 1998 Wiley-Liss, Inc.(dagger) C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Ricci, RM (reprint author), Wilford Hall USAF Med Ctr, Lackland AFB, San Antonio, TX 78236 USA. NR 12 TC 7 Z9 7 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 0196-8092 J9 LASER SURG MED JI Lasers Surg. Med. PY 1998 VL 22 IS 1 BP 10 EP 13 DI 10.1002/(SICI)1096-9101(1998)22:1<10::AID-LSM5>3.0.CO;2-# PG 4 WC Dermatology; Surgery SC Dermatology; Surgery GA YP485 UT WOS:000071281500005 PM 9443144 ER PT J AU Puffer, RL AF Puffer, RL TI Hitler: The pathology of evil. SO LIBRARY JOURNAL LA English DT Book Review C1 USAF, Hist Prog, Edwards AFB, CA 93523 USA. RP Puffer, RL (reprint author), USAF, Hist Prog, Edwards AFB, CA 93523 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 JAN PY 1998 VL 123 IS 1 BP 118 EP 118 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA YR709 UT WOS:000071522400198 ER PT S AU Pogue, RT Natarajan, LV Tondiglia, VP Siwecki, SA Sutherland, RL Bunning, TJ AF Pogue, RT Natarajan, LV Tondiglia, VP Siwecki, SA Sutherland, RL Bunning, TJ BE Khoo, IC TI Controlling nano-scale morphology in switchable PDLC gratings SO LIQUID CRYSTALS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Liquid Crystals II CY JUL 20-21, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers ID DISPERSED LIQUID-CRYSTALS; INDUCED PHASE-SEPARATION; BRAGG GRATINGS; POLYMER AB Gratings formed by anisotropic phase separation of liquid crystals show tremendous promise for switchable optical elements. Formation of useful gratings is linked to the control of the resulting nano-scale morphologies. In an attempt to decrease scatter and improve the electro-optic properties of polymer-dispersed liquid crystal (PDLC) volume transmission gratings we have evaluated the results of altering the relative concentrations of the components in the pre-polymer mixture. Discussion is made concerning the expected effects on polymerization and phase separation and how these changes are reflected in the film morphologies and electro-optical properties. Initial results indicate that changes in the concentration of co-initiator, chain extender, and effective monomer functionality have a significant effect on the size and shape of the LC domains at constant LC loading. C1 USAF, Res Lab, MLPJ, Wright Patterson AFB, OH 45432 USA. RP Pogue, RT (reprint author), USAF, Res Lab, MLPJ, Wright Patterson AFB, OH 45432 USA. NR 12 TC 11 Z9 12 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2930-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3475 BP 2 EP 11 DI 10.1117/12.326903 PG 10 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BM33A UT WOS:000078396900001 ER PT S AU Wick, DV Martinez, T Wilkes, JM Gruneisen, MT AF Wick, DV Martinez, T Wilkes, JM Gruneisen, MT BE Khoo, IC TI Development of a novel liquid crystal spatial light modulator for real-time holography SO LIQUID CRYSTALS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Liquid Crystals II CY JUL 20-21, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE liquid crystal; spatial light modulator; real-time holography AB Deformed-helix ferroelectric liquid-crystal media with high molecular tilt angles have been used in spatial light modulators to make them faster and more efficient. A prototype device developed for real-time holography applications has generated diffraction efficiencies as high as 38% and response times as short as 600 mu sec. C1 USAF, Res Lab, AFRL, DEBS, Kirtland AFB, NM 87117 USA. RP Wick, DV (reprint author), USAF, Res Lab, AFRL, DEBS, Kirtland AFB, NM 87117 USA. NR 7 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 0-8194-2930-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3475 BP 42 EP 48 DI 10.1117/12.326907 PG 7 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BM33A UT WOS:000078396900005 ER PT J AU Jata, KV Vasudevan, AK AF Jata, KV Vasudevan, AK TI Effect of fabrication and microstructure on the fracture initiation and growth toughness of Al-Li-Cu alloys SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE Al-Li-Cu alloys; growth toughness; fracture initiation ID ALUMINUM-ALLOYS; CRACK-GROWTH AB Fracture toughness properties of three microstructural variants of aluminum-lithium alloy 2020 (4.6 Cu, 1.1 Li-0.5 Mn-0.2 Cd), were analyzed. The first variant is the base alloy, REX-2020, which is completely recrystallized, The second variant was produced by thermomechanically processing the REX-2020 and the third variant was obtained by replacing Mn in the REX-2020 by Zr, as the grain refining element. These two versions of the alloy labeled as TMP-2020 and Zr-2020, resulted in an unrecrystallized microstructure. Fracture toughness data were analyzed in terms of crack initiation toughness K-Jc, and the crack growth toughness parameter, T-R (tearing modulus). The three variants of the alloy 2020 exhibit minimum differences in both the fracture initiation toughness, K-Jc, and the crack growth toughness, T-R, in the peak aged condition. However, a considerable improvement in K-Jc is observed in the thermo mechanically processed (TMP-2020) and the Zr containing 2020 (Zr-2020) in the underaged condition. The improvement in K-Jc in the TMP-2020 and Zr-2020 variants over the REX-2020, is attributed to a higher plasticity attainable at the crack tip and finer grain size. The tearing modulus, T-R, is however higher in the REX-2020 due to planar slip and conversely the lower T-R in the TMP-2020 and Zr-2020 is due to a lower degree of planar slip than the REX-2020 alloy. The low toughness at the peak age condition in the three alloys is due to grain boundary fracture from the presence of grain boundary precipitates. There is some recovery in this lost toughness in the overaged condition where plasticity is gained via the Loss in the yield strength of the alloys. (C) 1998 Elsevier Science S.A. C1 Wright Lab, MLLM, Mat Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. Off Naval Res, Arlington, VA 22217 USA. RP Jata, KV (reprint author), Wright Lab, MLLM, Mat Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. NR 16 TC 14 Z9 14 U1 0 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 PY 1998 VL 241 IS 1-2 BP 104 EP 113 DI 10.1016/S0921-5093(97)00479-6 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA YX503 UT WOS:000072046800012 ER PT J AU Frazier, WG Malas, JC Medina, EA Medeiros, S Venugopal, S Mullins, WM Chaudhary, A Irwin, RD AF Frazier, WG Malas, JC Medina, EA Medeiros, S Venugopal, S Mullins, WM Chaudhary, A Irwin, RD TI Application of control theory principles to optimisation of grain size during hot extrusion SO MATERIALS SCIENCE AND TECHNOLOGY LA English DT Article ID MANUFACTURE AB Modern control theory has been applied to the optimisation of microstructure development during hot extrusion. This approach involves state space type models for describing the material behaviour and the mechanics of the process. The problem of determining process control parameters such as str ain, strain rate, and temperature to obtain prespecified microstructural nl features can be systematically formulated in terms of an optimal control problem. This method has been applied to the optimisation of grain size and certain process parameters such as die geometry and ram velocity during extrusion of plain carbon steel. Experimental results of this investigation show good agreement with those predicted in the design stage. (C) 1998 The Institute of Materials. C1 Wright Lab, Mat Directorate, Wright Patterson AFB, OH USA. Ohio Univ, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. RP Frazier, WG (reprint author), Wright Lab, Mat Directorate, Wright Patterson AFB, OH USA. NR 18 TC 8 Z9 8 U1 1 U2 3 PU INST MATERIALS PI LONDON PA 1 CARLTON HOUSE TERRACE, LONDON SW1Y 5DB, ENGLAND SN 0267-0836 J9 MATER SCI TECH SER JI Mater. Sci. Technol. PD JAN PY 1998 VL 14 IS 1 BP 25 EP 31 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA YY979 UT WOS:000072207800004 ER PT J AU Semiatin, SL Seetharaman, V Dimiduk, DM Ashbee, KKG AF Semiatin, SL Seetharaman, V Dimiduk, DM Ashbee, KKG TI Phase transformation behavior of gamma titanium aluminide alloys during supertransus heat treatment SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Fundamentals of Gamma Titanium Aluminides at the TMS Annual Meeting CY FEB 10-12, 1997 CL ORLANDO, FL SP ASMI MSCTS Flow & Fracture Comm, ASMI MSCTS Phase Transformat Comm ID MICROSTRUCTURE DEVELOPMENT; GRAIN-GROWTH; HOMOGENIZATION AB Microstructure evolution in a wrought near-gamma titanium alloy, Ti-45Al-2Cr-2Nb, was investigated by a series of heat treatments comprised of initial heating high in the alpha-plus-gamma phase field followed by short-time heating in the single-phase alpha field. The initial heating step led to a dispersion of gamma particles which pinned the alpha grain boundaries. The kinetics of the gamma grain dissolution during subsequent heating in the single-phase field were interpreted in terms of models for both interface reaction-controlled and diffusion-controlled processes. The model for diffusion-controlled dissolution yielded predictions comparable to the observed times, whereas the model for interface reaction-controlled behavior predicted dissolution kinetics over an order of magnitude slower than observed. The growth of the alpha grains, both before and after the dissolution of the gamma phase, was also modeled. Section size limitations to the ability to use supertransus heating to obtain uniform and moderately fine alpha grain sizes were examined using the transformation models and a simple heat transfer analysis approach. The results were validated through the heat treatment of subscale and full-scale forgings. C1 USAF, Met Ceram & NDE Div, Struct Mat Grp, Mat & Mfg Directorate,Res Lab, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Mat & Proc Div, Dayton, OH 45432 USA. RP USAF, Met Ceram & NDE Div, Struct Mat Grp, Mat & Mfg Directorate,Res Lab, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 29 TC 28 Z9 29 U1 1 U2 6 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1073-5623 EI 1543-1940 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JAN PY 1998 VL 29 IS 1 BP 7 EP 18 DI 10.1007/s11661-998-0154-6 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA YU733 UT WOS:000071748800002 ER PT J AU Dimiduk, DM Hazzledine, PM Parthasarathy, TA Seshagiri, S Mendiratta, MG AF Dimiduk, DM Hazzledine, PM Parthasarathy, TA Seshagiri, S Mendiratta, MG TI The role of grain size and selected microstructural parameters in strengthening fully lamellar TiAl alloys SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article; Proceedings Paper CT Symposium on Fundamentals of Gamma Titanium Aluminides at the TMS Annual Meeting CY FEB 10-12, 1997 CL ORLANDO, FL SP ASMI MSCTS Flow & Fracture Comm, ASMI MSCTS Phase Transformat Comm ID DEFORMATION; CRYSTALS; DISLOCATIONS; COMPOUND; BEHAVIOR; STRESS; PHASE AB More than 5 years ago, wrought processing was first used to produce fully lamellar (FL) microstructures in TiAl alloys having grain sizes less than approximate to 400 mu m. These alloys exhibit an improvement in overall balance of properties, especially at high temperatures. More recently, such microstructural forms led to exceptional yield strengths (500 to 1000 MPa at low temperatures) while maintaining attractive high-temperature properties. The improvements appeared to be related to an unusually high apparent sensitivity of strength to grain size. Studies reported an apparent value for the slope of the Hall-Fetch (HP) plot approaching 5 MPa root m for FL gamma alloys, while that for single-phase or duplex microstructures is near unity. The present investigations examine the slope of the HP plot for FL microstructures, paying particular attention to the lamellar microstructural variables. Results show that the alpha(2) lamellar thickness and spacing and the gamma lamellar thickness can vary over more than two orders of magnitude with typical process methods. These spacings influence the value of k(y) in the HP (grain size) relationship. Since they often change concomitantly with grain size in processing, they can give rise to a large scatter in the HP plot. The investigations also examine the flow behavior, glide barriers, and slip multiplicity for polysynthetically twinned (PST) crystals (the single-grain analogue of FL material), and then map this behavior into an explanation of the yield behavior of high-strength FL gamma alloys. C1 Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45434 USA. Universal Energy Syst Inc, Div Mat Sci, Dayton, OH 45432 USA. RP Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45434 USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 40 TC 105 Z9 116 U1 1 U2 13 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1073-5623 EI 1543-1940 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD JAN PY 1998 VL 29 IS 1 BP 37 EP 47 DI 10.1007/s11661-998-0157-3 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA YU733 UT WOS:000071748800005 ER PT B AU Burns, DM Bright, VM AF Burns, DM Bright, VM GP IEEE TI Micro-electro-mechanical focusing mirrors SO MICRO ELECTRO MECHANICAL SYSTEMS - IEEE ELEVENTH ANNUAL INTERNATIONAL WORKSHOP PROCEEDINGS LA English DT Proceedings Paper CT 11th Annual International Workshop on Micro Electro Mechanical Systems CY JAN 25-29, 1998 CL HEIDELBERG, GERMANY SP IEEE, Robot & Automat Soc, ASME, Div Dynam Syst & Control, Minist Econ Affairs Baden Wurttemberg AB Novel surface-micromachined focusing mirrors have been designed, fabricated, and rested. The mirrors are constructed from concentric rings of polysilicon and gold, and connected by thin bridges of polysilicon. The outer ring of the mirror is lifted out of the plane of the substrate using thermal actuators to change the mirror's focal length. The focal lengths for I mm diameter mirrors have been driven over the range of 7.39 mm to 14.36 mm at frequencies beyond 120 Hz. The mirror may be able to correct both pincushion and barrel distortion. Applications for this minor include shaping laser spots for laser radars and holographic data storage, and dynamic focusing onto photodetectors for communication systems. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Burns, DM (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 0 TC 10 Z9 11 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4412-X PY 1998 BP 460 EP 465 DI 10.1109/MEMSYS.1998.659801 PG 2 WC Automation & Control Systems; Engineering, Biomedical; Engineering, Electrical & Electronic; Engineering, Mechanical SC Automation & Control Systems; Engineering GA BK78X UT WOS:000073380900083 ER PT J AU Sheu, S Liou, JJ Huang, CI AF Sheu, S Liou, JJ Huang, CI TI Numerical analysis on determining the physical mechanisms contributing to the abnormal base current in post-burn-in AlGaAs/GaAs HBTs SO MICROELECTRONICS AND RELIABILITY LA English DT Article AB An abnormal base current behavior with an ideality of about 3 is often observed in the AlGaAs/GaAs HBT after it is subjected to a high temperature/electrical burn-in condition. Using a two-dimensional device simulator, this paper studies and determines the main physical mechanisms contributing to such an abnormality. Data measured from two post-burn-in HBTs are included in support of the finding. (C) 1998 Published by Elsevier Science Ltd. C1 Univ Cent Florida, Dept Elect & Comp Engn, Orlando, FL 32816 USA. USAF, Wright Lab, Elect Technol Div, Wright Patterson AFB, OH 45433 USA. RP Sheu, S (reprint author), Univ Cent Florida, Dept Elect & Comp Engn, Orlando, FL 32816 USA. NR 8 TC 1 Z9 1 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 JAN PY 1998 VL 38 IS 1 BP 163 EP 170 DI 10.1016/S0026-2714(97)00071-1 PG 8 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA ZE234 UT WOS:000072771600016 ER PT S AU Hawley, RE AF Hawley, RE GP INST MECH ENGINEERS INST MECH ENGINEERS TI Mission training in the future SO MILITARY AEROSPACE TECHNOLOGIES - FITEC '98 SE IMECHE CONFERENCE TRANSACTIONS LA English DT Proceedings Paper CT Conference on Military Aerospace Technologies (FITEC 98) CY SEP 08-10, 1998 CL IEE SAVOY PL, LONDON, ENGLAND SP Soc British Aerosp Co, Royal Aeronaut Soc, IEE, Inst Mech Engineers HO IEE SAVOY PL C1 USAF, Air Combat Command, Langley, VA 23665 USA. RP Hawley, RE (reprint author), USAF, Air Combat Command, Langley, VA 23665 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MECHANICAL ENGINEERING PUBLISHING LTD PI BURY ST EDMUNDS PA NORTHGATE AVE, BURY ST EDMUNDS 1P32 6BW, SUFFOLK, ENGLAND SN 1356-1448 BN 1-86058-167-6 J9 IMECHE CONF TRANS PY 1998 VL 1998 IS 10 BP 137 EP 143 PG 7 WC Engineering, Aerospace; Engineering, Mechanical SC Engineering GA BL88D UT WOS:000077032200011 ER PT J AU Curphy, GJ Gibson, FW Macomber, G Calhoun, CJ Wilbanks, LA Burger, MJ AF Curphy, GJ Gibson, FW Macomber, G Calhoun, CJ Wilbanks, LA Burger, MJ TI Situational factors affecting peer reporting intentions at the US Air Force Academy: A scenario-based investigation SO MILITARY PSYCHOLOGY LA English DT Article ID WHISTLE-BLOWERS; BEHAVIOR AB This study extends Trevino and Victor's (1992) initial research on the factors affecting peer reporting intentions. Approximately 400 cadets from the U.S. Air Force Academy indicated peer reporting intentions for 12 scenarios that systematically varied (a) the emotional closeness of the person committing the misconduct, (b) the severity of the misconduct, and (c) the presence or absence of other witnesses to the misconduct. The results indicated all three situational factors significantly affected cadets' intentions to report potential honor code violations. Implications for a peer reporting model based on Latane and Darley's (1970) bystander intervention model are discussed. C1 Personnel Decis Int, Denver, CO 80237 USA. OppenheimerFunds Inc, Denver, CO USA. USAF Acad, Colorado Springs, CO 80840 USA. RP Curphy, GJ (reprint author), Personnel Decis Int, Metro Point,Suite 990,4600 S Ulster St, Denver, CO 80237 USA. NR 23 TC 6 Z9 6 U1 2 U2 7 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 1 BP 27 EP 43 DI 10.1207/s15327876mp1001_3 PG 17 WC Psychology, Multidisciplinary SC Psychology GA YV828 UT WOS:000071867400003 ER PT J AU Dansby, MR Landis, D AF Dansby, MR Landis, D TI Race, gender, and representation index as predictors of an equal opportunity climate in military organizations SO MILITARY PSYCHOLOGY LA English DT Article ID EMPIRICAL-TEST; TOKEN WOMEN; PROPORTIONS; BEHAVIORS AB Recent analyses of the perceptions of equal opportunity (EO) climate in the military highlight differences among various demographic subgroups. Prior research (Dansby, 1994) indicates minority female officers have the least favorable views of EO climate in military organizations when contrasted to comparable demographic subgroups (i.e., Caucasian male officers, etc.). Differences based on race, gender, and representation index (number in the subgroup divided by the total unit population) are explored in a sample of 190 U.S. Army units (N=47,823) that conducted the Military Equal Opportunity Climate Survey between 1990 and 1995. As predicted, minority female officers' perceptions of the favorability of the EO climate improved as their representation in the organization increased (p < .05). Contrary to the expected negative relation, higher educational attainment positively correlated with improved perceptions of EO climate. The findings are interpreted as supporting consideration of representation issues as a means to improving perceived EO climate. C1 DEOMI, DR, Patrick AFB, FL 32925 USA. Univ Mississippi, Dept Psychol, University, MS 38677 USA. RP Dansby, MR (reprint author), DEOMI, DR, 740 OMalley Rd MS9121, Patrick AFB, FL 32925 USA. NR 39 TC 11 Z9 11 U1 1 U2 1 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0899-5605 J9 MIL PSYCHOL JI Milit. Psychol. PY 1998 VL 10 IS 2 BP 87 EP 105 DI 10.1207/s15327876mp1002_2 PG 19 WC Psychology, Multidisciplinary SC Psychology GA ZJ443 UT WOS:000073216200003 ER PT S AU Michalicek, MA Comtois, JH Schriner, HK AF Michalicek, MA Comtois, JH Schriner, HK BE Motamedi, ME Goring, R TI Design and fabrication of optical MEMS using a four-level, planarized, surface-micromachined polycrystalline silicon process SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MICROMECHANICS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and Micromechanics III CY JAN 26-27, 1998 CL SAN JOSE, CA SP SPIE Int Soc Opt Engn DE MEMS; micromirrors; FBMD; ARMD; optical MEMS; MOEMS; SUMMiT; metallization; planarization AB This paper describes the design and fabrication of optical microelectromechanical systems (MEMS) devices using the Sandia Ultra-planar Multi-level MEMS Technology (SUMMiT) fabrication process. his state-of-the-art process, offered by Sandia National Laboratories, provides unique and very advantageous features which make it ideal for optical devices such as micromirrors. This enabling process permits the development of micromirror devices with near-ideal characteristics which have previously been unrealizable in standard polysilicon processes. This paper describes many of these characteristics such as elevated address electrodes, various address wiring techniques, planarized mirror surfaces using Chemical Mechanical Polishing (CMP), unique post-process metallization, and the best active surface area to date. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Michalicek, MA (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 TC 15 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 0-8194-2715-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3276 BP 48 EP 55 DI 10.1117/12.302408 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BK71W UT WOS:000073206500005 ER PT S AU Watson, EA Miller, DT Barnard, KJ AF Watson, EA Miller, DT Barnard, KJ BE Motamedi, ME Goring, R TI Analysis of pill factor improvement using microlens arrays SO MINIATURIZED SYSTEMS WITH MICRO-OPTICS AND MICROMECHANICS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Miniaturized Systems with Micro-Optics and Micromechanics III CY JAN 26-27, 1998 CL SAN JOSE, CA SP SPIE Int Soc Opt Engn DE microlens arrays; fill factor; detector arrays; spatial light modulators AB Optoelectronic devices often make use of detectors or spatial light modulators. These components frequently are integrated with other electronics or devices that limit their fill factor on the substrate to less than unity. A frequently quoted approach to overcoming the fill factor problem is to use microlens arrays in conjunction with the components to increase the fill factor to near unity. However, the effect of the field angle over which the devices must operate is often not considered. In this paper we present results of geometric and physical optic analyses of microlens arrays in conjunction with detectors and modulators. Design equations for the microlens arrays are derived, the effect of field angle is quantified, and expected fill factor improvement is presented. Examples of possible systems applications are also considered. C1 USAF, Res Lab, Electroopt Sensor Technol Branch, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Watson, EA (reprint author), USAF, Res Lab, Electroopt Sensor Technol Branch, Sensors Directorate, 3109 P St,Bldg 622, Wright Patterson AFB, OH 45433 USA. NR 0 TC 5 Z9 5 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 0-8194-2715-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3276 BP 123 EP 134 DI 10.1117/12.302390 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BK71W UT WOS:000073206500013 ER PT S AU Stytz, MR Banks, SB Santos, E AF Stytz, MR Banks, SB Santos, E BE Illgen, JD Trier, EA TI An overview of the distributed mission training integrated threat environment project SO MODELING AND SIMULATING SENSORY RESPONSE FOR REAL AND VIRTUAL ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Modeling and Simulating Sensory Response for Real and Virtual Environments CY APR 16, 1998 CL ORLANDO, FL SP Int Soc Optical Engn DE distributed virtual environments; distributed mission training; computer-generated forces; High Level Architecture; and threat modeling AB The Joint Synthetic Battlespace (JSB) envisioned within the Department of Defense modeling and simulation master plan requires a distributed virtual environment (DVE) wide consistent threat environment to achieve a useful mission rehearsal, training, test and evaluation capability. To achieve this objective, all threats in the DVE must appear at compatible levels of fidelity to all the entities operating in the DVE and they must interact with human-operated and computer-controlled entities in a realistic fashion. Achieving this goal is not currently possible for two reasons. First, each primary aircraft simulator training system developer has created their own threat system and made their own modeling decisions to support a specific user for a select few predetermined conditions. This traditional threat simulation approach is expensive and leads to ongoing difficulties in maintaining threat currency as intelligence updates are made, new weapons are introduced and new theaters of operation are identified. Second, the threat system interaction on a distributed network must be coordinated. The individualized nature of current threat systems precludes the possibility of introducing coordinated threats. The Distributed Mission Training Integrated Threat Environment (DMTITE) Project is developing an effective solution to these issues. The DMTITE project is identifying the requirements for a distributed threat environment and building a demonstrator DOD High Level Architecture (HLA) compatible system that can provide realistic threats for pilots to train against. The DMTITE prototype will instantiate a variety of threats for use in distributed training scenarios, including surface threats, air threats, radars, and jamming systems. A key element of the system will be the provision of realistic behaviors for the threat systems. We based DMTITE on a general software design methodology and software architecture for computer-generated forces (CGFs) that naturally supports "variety" in performance for a given type of CGF and allows us to organize and build vastly different CGFs within the same architecture. This approach allows us to provide a range of threat skill levels for each threat modeled within the DMTITE system and we can readily expand the system to accommodate peer-to-peer communication and group tactics. In this paper, we present a brief overview of the DMTITE requirements and a component-wise decomposition of the system. We also describe the structure of the major components of the DMT threat system's decision mechanism. The progress of the initial prototype will also be discussed. C1 USAF, Inst Technol, Artificial Intelligence Lab, Wright Patterson AFB, OH 45433 USA. RP Stytz, MR (reprint author), USAF, Inst Technol, Artificial Intelligence Lab, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2816-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3367 BP 2 EP 13 DI 10.1117/12.317562 PG 12 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Optics SC Engineering; Computer Science; Optics GA BL60W UT WOS:000075999500001 ER PT S AU Stytz, MR Banks, SB Lewis, J Johnson, T AF Stytz, MR Banks, SB Lewis, J Johnson, T BE Illgen, JD Trier, EA TI The virtual prototype interface for the air force manned SpacePlane project SO MODELING AND SIMULATING SENSORY RESPONSE FOR REAL AND VIRTUAL ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Modeling and Simulating Sensory Response for Real and Virtual Environments CY APR 16, 1998 CL ORLANDO, FL SP Int Soc Optical Engn DE distributed interactive simulation; distributed virtual environments; spaceplane; virtual prototyping; virtual environment user interface; rapid interface prototyping; virtual environments; training systems AB The advent of requirements for worldwide deployment of space assets in support of Air Force operational missions has resulted in the need for a Manned SpacePlane (MSP) that can perform these missions with minimal preflight preparation and little, if any, in-orbit support from a mission control center. Because successful mission accomplishment will depend almost completely upon the MSP crew and the on-board capabilities of the spaceplane, the MSP user interface is a crucial component of successful mission accomplishment. In recognition of this fact, the USAF Phillips Laboratory in conjunction with USAF Space Command initiated the Virtual SpacePlane (VSP) project. To function effectively as an MSP interface development platform, the VSP must demonstrate the capability to simulate anticipated MSP missions and portray the MSP in operation throughout its entire flight regime, from takeoff through space operations and on to recovery via a horizontal landing at an airfield. Therefore, we architected, designed, and implemented a complete VSP that can be used to simulate anticipated Manned SpacePlane missions. The primary objective of the VSP is to be a virtual prototype for user interface design and development, the VSP software architecture and design facilitates uncovering, refining and validating MSP user interface requirements. The Virtual SpacePlane reuses software components developed for the Virtual Cockpit (VC) and Solar System Modeler (SM) distributed virtual environment (DVE) applications, the Common Object Database (CODB) architecture, and Information Pod (Pod) interface tools developed in our Labs. The Virtual Cockpit and Solar System Modeler supplied baseline interface components and tools, 3D graphical models, vehicle motion dynamics models, and DVE communication capabilities. Because we knew that the VSP's requirements would expand and evolve over the life of the project, we use the CODE architecture to facilitate our use of Rapid Evolutionary and Exploratory Prototyping (REEP) to uncover application requirements and evaluate solutions. The Information Pod provides the paradigm and architectural framework for the user interface development. To achieve accurate and high fidelity performance for the VSP throughout its operational re,regime, the system integrates aerodynamics and astrodynamics models from the VC, SM and other sources into a single seamless high fidelity model of the VPS's dynamics. In this paper we discuss the background to the VSP project, its requirements, and the current user interface design. We summarize the VSP's current status and outline our plans for further VSP interface development and testing. C1 USAF, Inst Technol, Virtual Environm Lab, Human Comp Lab, Wright Patterson AFB, OH 45433 USA. RP Stytz, MR (reprint author), USAF, Inst Technol, Virtual Environm Lab, Human Comp Lab, Wright Patterson AFB, OH 45433 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 0-8194-2816-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3367 BP 14 EP 25 DI 10.1117/12.317569 PG 12 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Optics SC Engineering; Computer Science; Optics GA BL60W UT WOS:000075999500002 ER PT S AU Van Veldhuizen, DA Lamont, GB Santos, E AF Van Veldhuizen, DA Lamont, GB Santos, E BE Illgen, JD Trier, EA TI Comparing computer generated military actors with specific skills SO MODELING AND SIMULATING SENSORY RESPONSE FOR REAL AND VIRTUAL ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Modeling and Simulating Sensory Response for Real and Virtual Environments CY APR 16, 1998 CL ORLANDO, FL SP Int Soc Optical Engn DE computer generated actors (CGAs); behavior evaluation; skills AB The US military sees a great use for software agent technology in its "synthetic battlespace", a Distributed Virtual Environment currently used as a training and planning arena. The Computer Generated Actors (CGAs) currently used in the battlespace display varying capabilities, but state of the art falls short of presenting believable agents. This lack: of "believability" directly contributes to simulation and participant inconsistencies. Even if CGAs display believable behavior no formalized methodology exists for judging that display or for comparing CGA performance. A formal method is required to obtain a quantitative measurement of performance for use in assessing a CGA's performance in some simulation, and thus its suitability for use in the battlespace. This paper proposes such a quantitative evaluation method for determining an agent's observed degree of performance as related to skills. Since the method delineates what is being measured and the criteria upon which the measurement is based, it also explains the particular evaluation given for specific military CGAs. C1 USAF, Dept Elect & Comp Engn, Grad Sch Engn, Wright Patterson AFB, OH 45433 USA. RP Van Veldhuizen, DA (reprint author), USAF, Dept Elect & Comp Engn, Grad Sch Engn, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2816-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3367 BP 26 EP 32 DI 10.1117/12.317571 PG 7 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Optics SC Engineering; Computer Science; Optics GA BL60W UT WOS:000075999500003 ER PT S AU Banks, SB Stytz, MR Rothermel, SA Johnson, TD AF Banks, SB Stytz, MR Rothermel, SA Johnson, TD BE Illgen, JD Trier, EA TI An architecture and design to support rapid prototyping and multiple dynamics models for the Virtual SpacePlane project SO MODELING AND SIMULATING SENSORY RESPONSE FOR REAL AND VIRTUAL ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Modeling and Simulating Sensory Response for Real and Virtual Environments CY APR 16, 1998 CL ORLANDO, FL SP Int Soc Optical Engn DE distributed virtual environments; virtual prototyping; manned simulators; dynamics model switching; spaceplane; training systems; rapid prototyping AB The advent of requirements for rapid and economical deployment of national space assets in support of Air Force operational missions has resulted in the need for a Manned SpacePlane (MSP) that can perform military missions with minimal preflight preparation and little if any in-orbit support from a mission control center. In this new approach to space operations, successful mission accomplishment will depend almost completely upon the MSP crew and upon the on-board capabilities of the spaceplane. In recognition of the challenges that will be faced by the MSP crew and to begin to address these challenges, the USAF Air Force Research Laboratory (Phillips Laboratory) initiated the Virtual SpacePlane (VSP) project. To support the MSP, the VSP must demonstrate a broad, functional subset of the anticipated missions and capabilities of the MSP throughout it entire flight regime, from takeoff through space operations and on through landing. Additionally, the VSP must execute the anticipated MSP missions in a realistic and tactically sound manner within a distributed virtual environment. Furthermore, the VSP project must also uncover, refine and validate MSP user interface requirements, design and demonstrate an intelligent user interface for the VSP, and design and implement a prototype VSP that can be used to demonstrate Manned SpacePlane missions. To enable us to make rapid progress on the project, we employed portions of the Virtual Cockpit and Solar System Modeler distributed virtual environment (DVE) applications, and the Common Object Database (CODB) architecture tools developed in our Labs. The Virtual Cockpit and Solar System Modeler supplied baseline interface components and tools, 3D graphical models, vehicle motion dynamics models, and DVE communication capabilities. We use the CODE architecture to facilitate our use of Rapid Evolutionary and Exploratory Prototyping to uncover application requirements and evaluate solutions. The Information Pod provides the paradigm and architectural framework for the user interface development. To achieve accurate and high fidelity performance for the VSP throughout its operational regime, the system integrates aerodynamics and astrodynamics models into a single seamless high fidelity model of the VPS's dynamics. In this paper we discuss the software architecture and design of the Virtual SpacePlane and describe how it supports the transition between motion models, the design of the dynamics software module, and techniques for employment of multiple dynamics models within a single virtual environment actor. We describe how we used rapid prototyping to refine requirements, improve the implementation, and accommodate new requirements throughout the project. We conclude the paper with a brief discussion of results and present suggestions for additional work. C1 USAF, Inst Technol, Human Comp Interact Lab, Virtual Environm Lab, Wright Patterson AFB, OH 45433 USA. RP Banks, SB (reprint author), USAF, Inst Technol, Human Comp Interact Lab, Virtual Environm Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2816-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3367 BP 33 EP 44 DI 10.1117/12.317572 PG 12 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Optics SC Engineering; Computer Science; Optics GA BL60W UT WOS:000075999500004 ER PT J AU Libby, A O'Connell, P Allred, DC AF Libby, A O'Connell, P Allred, DC TI Lobular carcinoma in situ: Biologic features including loss of heterozygosity. SO MODERN PATHOLOGY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Univ Texas, Hlth Sci Ctr, San Antonio, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0893-3952 J9 MODERN PATHOL JI Mod. Pathol. PD JAN PY 1998 VL 11 IS 1 BP 22A EP 22A PG 1 WC Pathology SC Pathology GA YV140 UT WOS:000071793400130 ER PT J AU Libby, A Hilsenbeck, SG Elledge, RM Allred, DC AF Libby, A Hilsenbeck, SG Elledge, RM Allred, DC TI Biologic characteristics of special-type (ST) compared to no-special-type (NST) invasive breast cancers SO MODERN PATHOLOGY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Univ Texas, Hlth Sci Ctr, San Antonio, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0893-3952 J9 MODERN PATHOL JI Mod. Pathol. PD JAN PY 1998 VL 11 IS 1 BP 23A EP 23A PG 1 WC Pathology SC Pathology GA YV140 UT WOS:000071793400131 ER PT J AU Moinfar, F Man, YG Lininger, RA Tavassoli, FA AF Moinfar, F Man, YG Lininger, RA Tavassoli, FA TI Use of keratin34 beta E12 as an adjunct in the diagnosis of mammary intraepithelial neoplasia ductal type (benign and malignant intraductal proliferations of the breast) SO MODERN PATHOLOGY LA English DT Meeting Abstract C1 USAF, Inst Pathol, GYN & Breast Dept, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0893-3952 J9 MODERN PATHOL JI Mod. Pathol. PD JAN PY 1998 VL 11 IS 1 BP 23A EP 23A PG 1 WC Pathology SC Pathology GA YV140 UT WOS:000071793400135 ER PT J AU Kung, P Saxler, A Walker, D Rybaltowski, A Zhang, XL Diaz, J Razeghi, M AF Kung, P Saxler, A Walker, D Rybaltowski, A Zhang, XL Diaz, J Razeghi, M TI GaIn/N/GaN multi-quantum well laser diodes grown by low-pressure metalorganic chemical vapor deposition SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID GAN AB We report the growth, fabrication and characterization of GaInN/GaN multi-quantum well lasers grown on (00.1) sapphire substrates by low pressure metalorganic chemical vapor deposition. The threshold current density of a 1800 mu m long cavity length laser was 1.4 kA/cm(2) with a threshold voltage of 25 V. These lasers exhibited series resistances of 13 and 14 Ohm at 300 and 79 K, respectively. C1 Northwestern Univ, Dept Elect & Comp Engn, Ctr Quantum Devices, Evanston, IL 60208 USA. USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Kung, P (reprint author), Northwestern Univ, Dept Elect & Comp Engn, Ctr Quantum Devices, Evanston, IL 60208 USA. RI Razeghi, Manijeh/B-7265-2009 NR 10 TC 9 Z9 9 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 1092-5783 J9 MRS INTERNET J N S R JI Mrs. Internet J. Nitride Semicond. Res. PY 1998 VL 3 IS 1 BP art. no. EP 1 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA YR251 UT WOS:000071476100001 ER PT S AU Choi, DS Agaian, S Noonan, J AF Choi, DS Agaian, S Noonan, J BE Kuo, CCJ Chang, SF Panchanathan, S TI Hybrid subband coder SO MULTIMEDIA STORAGE AND ARCHIVING SYSTEMS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Multimedia Storage and Archiving Systems III CY NOV 02-04, 1998 CL BOSTON, MA SP SPIE Int Soc Opt Engn DE subband coding; nonlinear filters; morphological filters; hybrid subband coder; image compression AB In this article, we introduce a new subband structure called hybrid subband coder (HSC), which uses both linear and morphological filters at each analysis and synthesis stage. This new subband coder significantly reduces the ringing-effect distortions inherent to the linear subband coders (LSC) and the smearing-effect distortions associated with the nonlinear, morphological subband coders (MSC). The performance of this new structure is compared to the linear and nonlinear subband coder results using a set of four grayscale images. The results show a modest improvement in PSNR and in visual quality. C1 USAF, Res Lab, SNHE, Bedford, MA 01731 USA. RP Choi, DS (reprint author), USAF, Res Lab, SNHE, Bedford, MA 01731 USA. NR 0 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 0-8194-2988-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3527 BP 505 EP 517 DI 10.1117/12.325843 PG 13 WC Computer Science, Software Engineering SC Computer Science GA BL92K UT WOS:000077158600047 ER PT J AU Lillie, TH Ripley, JD AF Lillie, TH Ripley, JD TI A strategy for implementing ecosystem management in the United States Air Force SO NATURAL AREAS JOURNAL LA English DT Article DE biodiversity; ecosystem management; stewardship; sustainable development AB The U.S. Air Force is entrusted with stewardship of a diversity of natural resources on installations throughout the United States. For many years these resources were managed with a commodities-based approach emphasizing multiple use, sustained yield, and the protection of single species regulated under the Endangered Species Act. Beginning in 1992, Air Force policymakers and field personnel recognized a need to adopt a new management policy. An ecosystem-based approach was adopted as a process for making, implementing, and evaluating decisions affecting the management of natural resources. This approach was implemented with a new policy directive, changes in funding priorities, and a new training course. We believe the ecosystem approach will better support the military mission and ensure the sustainability of natural resources on U.S. Air Force installations. C1 USAF, Ranges & Airspace Div, Washington, DC 20330 USA. RP Lillie, TH (reprint author), USAF, Ranges & Airspace Div, 1480 Air Force Pentagon, Washington, DC 20330 USA. NR 27 TC 3 Z9 3 U1 0 U2 1 PU NATURAL AREAS ASSOCIATION PI ROCKFORD PA 320 SOUTH THIRD STREET, ROCKFORD, IL 61104 USA SN 0885-8608 J9 NAT AREA J JI Nat. Areas J. PD JAN PY 1998 VL 18 IS 1 BP 73 EP 80 PG 8 WC Ecology; Forestry SC Environmental Sciences & Ecology; Forestry GA YW712 UT WOS:000071965000009 ER PT J AU Chen, CLP LeClair, SR Pao, YH AF Chen, CLP LeClair, SR Pao, YH TI An incremental adaptive implementation of functional-link processing for function approximation, time-series prediction, and system identification SO NEUROCOMPUTING LA English DT Article DE instant learning algorithm; function approximations; least squares; forecasting; functional-link neural network; time-series; system identification ID NETWORKS; ALGORITHM AB This paper presents an adaptive implementation of the functional-link neural network (FLNN) architecture together with a supervised learning algorithm that rapidly determines the weights of the network. The proposed algorithm is able to achieve 'one-shot' training as opposed to iterative training algorithms in the literature. Also discussed is a stepwise updating algorithm that updates the weights of the network while importing new observations. The proposed algorithms have also been tested on several data sets and the simulation shows a very promising result. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Wright State Univ, Dept Comp Engn & Sci, Dayton, OH 45435 USA. USAF, Wright Lab, Mat Proc Design Branch, Mat Directorate,MLIM, Wright Patterson AFB, OH 45433 USA. Case Western Reserve Univ, Dept Elect Engn & Appl Phys, Cleveland, OH 44106 USA. RP Chen, CLP (reprint author), Wright State Univ, Dept Comp Engn & Sci, 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 22 TC 34 Z9 34 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0925-2312 J9 NEUROCOMPUTING JI Neurocomputing PD JAN PY 1998 VL 18 IS 1-3 BP 11 EP 31 DI 10.1016/S0925-2312(97)00062-3 PG 21 WC Computer Science, Artificial Intelligence SC Computer Science GA YV729 UT WOS:000071856900002 ER PT B AU Cliver, EW Webb, DF AF Cliver, EW Webb, DF BE Webb, D Rust, D Schmieder, B TI Disappearances of high-latitude filaments as sources of high-latitude CMEs SO NEW PERSPECTIVES ON SOLAR PROMINENCES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT IAU Colloquium 167 on New Perspectives on Solar Prominences CY APR 28-MAY 03, 1997 CL CTR PAUL LANGEVIN, AUSSOIS, FRANCE SP Intl Astron Union, Sci Comm Solar Terr Phys, European Off Aerosp Res & Dev, CNRS, Observ Paris, CEA, Ctr Natl Etud Spat HO CTR PAUL LANGEVIN AB From a statistical comparison of high-latitude coronal mass ejections (CMEs) and disappearing solar filaments (DSFs), we find: (1) Beginning with the "rush to the poles", DSFs arise at an increasing rate from the "emerging" or polar crown relative to the "true" polar crown. At maximum, these "opposite polarity" filaments are the dominant source of high-latitude DSFs. Following polarity reversal, the emergent polar crown becomes the true polar crown and the source of virtually all high-latitude DSFs. (2) At the last two solar maxima, we estimate that there were similar to 4 times as many high-latitude (greater than or equal to 60 degrees) CMEs as high-latitude (greater than or equal to 45 degrees) DSFs. Possible reasons for this discrepancy include the following: (a) DSFs, particularly small ones, are under-reported, (b) propagation effects, whereby radially propagating CMEs appear at higher latitudes than their underlying source regions, are more important than currently thought, or (c) some combination of these effects. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Cliver, EW (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 0 TC 8 Z9 8 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-70-8 J9 ASTR SOC P PY 1998 VL 150 BP 479 EP 483 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL75E UT WOS:000076565100093 ER PT J AU Kalns, J Parker, J Bruno, J Holwitt, E Piepmeier, E Kiel, J AF Kalns, J Parker, J Bruno, J Holwitt, E Piepmeier, E Kiel, J TI Nitrate reductase alters 3-nitrotyrosine accumulation and cell cycle progression in LPS+IFN-gamma-stimulated RAW 264.7 cells SO NITRIC OXIDE-BIOLOGY AND CHEMISTRY LA English DT Article DE nitrotyrosine; peroxynitrite; nitrite; nitrate reductase; RAW 264.7 ID NITRIC-OXIDE; LIPID-PEROXIDATION; TYROSINE PHOSPHORYLATION; PEROXYNITRITE; SUPEROXIDE; GENERATION; DISEASE AB Nitrite (NO2-), an end product of nitrogen radical metabolism, has recently been shown to increase tyrosine nitration by activated leukocytes indicating that nitrite modulates the immune response. We investigated the hypothesis that nitrite may increase nitration of molecular targets within activated cells leading to altered cell cycle progression. Intracellular nitrite was increased by transfection of murine macrophage-like RAW 264.7 cells with the nitrate reductase gene obtained from barley. Nitrate reductase facilitates the conversion of nitrate to nitrite; thus when extracellular nitrate is present, intracellular nitrite will be increased. Results show that addition of KNO3 increases NO2- production and intracellular nitrotyrosine accumulation in the transfectant but not the parent. Inhibition of nitric oxide synthesis with L-NAME during activation with IFN-gamma + LPS reduced NO2- production to the same extent in both cell lines; however, cellular accumulation of nitrotyrosine was reduced by only 25% in the transfectant (P = 0.21) and 49% in the parent cell line (P = 0.007), suggesting that intracellular nitrite increased nitrotyrosine accumulation through a pathway not requiring NO synthesis, i.e., myeloperoxidase system. Approximately 15% of the transfected cells had 4n DNA content 24 h postactivation compared to < 1% of the parent cells. Increased DNA copy number was correlated to nitrotyrosine accumulation. These findings show that intracellular nitrite can increase accumulation of nitrotyrosine and that nitration is linked to cell cycle perturbation. (C) 1998 Academic Press. C1 Armstrong Lab, AOH 2509, Brooks AFB, TX 78235 USA. Directed Energy Div, Brooks AFB, TX 78235 USA. RP Kalns, J (reprint author), Armstrong Lab, AOH 2509, Kennedy Circle,Suite 309, Brooks AFB, TX 78235 USA. NR 21 TC 4 Z9 4 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1089-8603 J9 NITRIC OXIDE-BIOL CH JI Nitric Oxide-Biol. Chem. PY 1998 VL 2 IS 5 BP 366 EP 374 DI 10.1006/niox.1998.0191 PG 9 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 174YM UT WOS:000079064200006 PM 10100492 ER PT S AU Yip, PW Wang, SQ Drehman, AJ Zhu, LD Norris, PE AF Yip, PW Wang, SQ Drehman, AJ Zhu, LD Norris, PE BE Ponce, FA DenBaars, SP Meyer, BK Nakamura, S Strite, S TI Investigation of nucleation and initial stage of GaN growth by atomic force microscopy and X-ray diffraction SO NITRIDE SEMICONDUCTORS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nitride Semiconductors, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Aixtron Semiconductor Technol GmbH, Bede Sci Inc, EMCORE, Lake Shore Cryotron Inc, Morton Int, MMR Technol Inc, Nichia Chem Ind, Renishaw PLC, Rockwell Int, Siemens, SULA Technol, SVT Assoc Inc, Thomas Swan & Co Ltd, Toyoda Gosel Co Ltd, Xerox Palo Alto Res Ctr AB The nucleation and initial stage of GaN growth on sapphire was investigated by atomic force microscopy, X-ray diffraction and photoluminescence. A 15 to 30 nm thick GaN buffer layer deposited at proper conditions was extremely smooth and nearly amorphous. Proper post deposition annealing resulted in the buffer crystallized. The buffer layer deposition temperature, thickness and annealing time and temperature must be coordinated. Low deposition temperature and/or insufficient annealing of the buffer results in a GaN wafer which has fine spiking surface morphology with an RMS of 3.4 nm for 1.3 mu m wafer, strong yellow luminescence and wide xray rocking curve FWHM. High deposition temperature, longer crystallization time, and a low growth rate results in a wafer which exhibits strong band edge luminescence without noticeable yellow luminescence, and a narrow (002) diffraction rocking curve. However, the surface morphology exhibits well developed hexagonal feature with RMS roughness of 14.3 nm for a 570 nm thick layer. X-ray rocking curve analysis revealed buffer crystallization, domain coalescence and alignment process. The FWHM of the omega-scan of GaN (101) diffraction was 1700-2000 arc seconds for 200-1400 nm wafers which indicates that the twist of the domains is not changing much with the growth. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Yip, PW (reprint author), USAF, Res Lab, 80 Scott Dr, Hanscom AFB, MA 01731 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-387-8 J9 MATER RES SOC SYMP P PY 1998 VL 482 BP 93 EP 98 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98K UT WOS:000073983100014 ER PT S AU Drehman, AJ Wang, SQ Yip, PW AF Drehman, AJ Wang, SQ Yip, PW BE Ponce, FA DenBaars, SP Meyer, BK Nakamura, S Strite, S TI Ultra-smooth ZnO buffer layers on (001) sapphire SO NITRIDE SEMICONDUCTORS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nitride Semiconductors, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Aixtron Semiconductor Technol GmbH, Bede Sci Inc, EMCORE, Lake Shore Cryotron Inc, Morton Int, MMR Technol Inc, Nichia Chem Ind, Renishaw PLC, Rockwell Int, Siemens, SULA Technol, SVT Assoc Inc, Thomas Swan & Co Ltd, Toyoda Gosel Co Ltd, Xerox Palo Alto Res Ctr AB Using off-axis reactive rf sputtering, we have grown extremely smooth, nearly epitaxial, (001) oriented ZnO films on c-axis sapphire substrates. Atomic Force Microscopy was used to determine that these films are extremely smooth, having an rms roughness of only a few tenths of a nanometer. Based on high resolution x-ray diffraction (HXRD), the ZnO is highly oriented, with a rocking curve width of less than 400 are seconds for the (006) diffraction peak, and only somewhat larger for the (112) reflection. HXRD Phi scans show that the ZnO (112) reflection is rotated in the a-b plane by 30 degrees from the sapphire (113) direction. These two measurements indicate excellent in-plane orientation. We are investigating the use of these buffer layers for subsequent GaN growth. Electrical resistivities of the films exceeded 100 k Omega-cm making ZnO a potential candidate as an insulating buffer layer. C1 USAF, Res Lab, SNHX, Bedford, MA 01731 USA. RP Drehman, AJ (reprint author), USAF, Res Lab, SNHX, 80 Scott Dr, Bedford, MA 01731 USA. NR 0 TC 5 Z9 5 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-387-8 J9 MATER RES SOC SYMP P PY 1998 VL 482 BP 289 EP 294 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98K UT WOS:000073983100042 ER PT S AU Webster, RT Anwar, AFM AF Webster, RT Anwar, AFM BE Ponce, FA DenBaars, SP Meyer, BK Nakamura, S Strite, S TI New method of computing band offsets and its application to AlGaN/GaN heterostructures SO NITRIDE SEMICONDUCTORS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nitride Semiconductors, at the 1997 MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc, Aixtron Semiconductor Technol GmbH, Bede Sci Inc, EMCORE, Lake Shore Cryotron Inc, Morton Int, MMR Technol Inc, Nichia Chem Ind, Renishaw PLC, Rockwell Int, Siemens, SULA Technol, SVT Assoc Inc, Thomas Swan & Co Ltd, Toyoda Gosel Co Ltd, Xerox Palo Alto Res Ctr AB Calculated sheet carrier concentration as a function of Al mole fraction in the quantum well (QW) formed at the GaN/AlGaN heterointerface is calculated and compared to experimental data. Close agreement between experiment and theory is observed. The calculated sheet carrier concentration reflects the maximum carrier concentration possible in the GaN QW for a given Al mole fraction and can not be used to argue in favor of either interface charge or piezoelectric effect as giving rise to the carriers. Based on experimental data the charge density in the AlGaN layer is estimated to be 4 x 10(12) cm(-2). The calculations are based upon a simple technique to determine valence band alignments. Calculated values are compared to experimental data showing excellent agreement. A calculated valence band discontinuity of 0.42eV for AlN/GaN is well within the experimental bounds. C1 USAF, Res Lab, Hanscom AFB, MA 01730 USA. RP Webster, RT (reprint author), USAF, Res Lab, Hanscom AFB, MA 01730 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-387-8 J9 MATER RES SOC SYMP P PY 1998 VL 482 BP 929 EP 934 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Engineering; Materials Science GA BK98K UT WOS:000073983100141 ER PT S AU Mullins, WM Shamachary, SS AF Mullins, WM Shamachary, SS BE Crane, RL Achenbach, JD Shah, SP Matikas, TE KhuriYakub, PT Gilmore, RS TI Ultrasonic quantification of corroded surfaces SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IN AGING SYSTEMS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nondestructive Characterization of Materials in Aging Systems CY NOV 30-DEC 04, 1997 CL BOSTON, MA SP Mat Res Soc AB The surface damage introduced by general corrosion attack of surfaces is considered deleterious to long term structural integrity. As a result, the quantification of this damage represents an interest in the NDE community. In this document, the chemical kinetics of general attack are used to model the morphology of the surface as a function of time of exposure. Time-of-flight ultrasonic data for corroded surfaces are presented which appear to agree with the model predictions. The experimental results are critically reviewed with respect to the practical limitations of the ultrasonic experiments. The effect of exposure on surface morphology and surface stress concentration are shown and related to the classic ultrasonic measurement techniques. The relationships are used to suggest potentially important ultrasonic measurement techniques and to underline the inherent limitations of many classical ultrasonic measurements. C1 ARFL, MLLP, TMCI, Wright Patterson AFB, OH 45433 USA. RP Mullins, WM (reprint author), ARFL, MLLP, TMCI, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-408-4 J9 MATER RES SOC SYMP P PY 1998 VL 503 BP 37 EP 46 PG 10 WC Engineering, Civil; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BL56M UT WOS:000075897100005 ER PT S AU Blodgett, MP Nagy, PB AF Blodgett, MP Nagy, PB BE Crane, RL Achenbach, JD Shah, SP Matikas, TE KhuriYakub, PT Gilmore, RS TI The role of grain noise in eddy current inspection of titanium alloys SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IN AGING SYSTEMS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nondestructive Characterization of Materials in Aging Systems CY NOV 30-DEC 04, 1997 CL BOSTON, MA SP Mat Res Soc AB This paper discusses the role electrical anisotropy plays in the structural integrity assessment of polycrystalline titanium alloys from the standpoint of fatigue crack detection and the related issue of microstructural noise. In eddy current inspection of noncubic crystallographic classes of polycrystalline metals the electric anisotropy of individual grains produces an inherent microstructural variation or noise that is very similar to the well-known acoustic noise produced by the elastic anisotropy of both cubic and noncubic materials in ultrasonic characterization. The presented results demonstrate that although the electrical grain noise is detrimental in eddy current nondestructive testing for small flaws, it can be also exploited for characterization of the microstructure in noncubic polycrystalline materials such as titanium alloys in the same way acoustic grain noise is used for ultrasonic characterization of the microstructure in different materials. C1 USAF, Res Lab, Met Ceram & NDE Div, Wright Patterson AFB, OH 45433 USA. RP Blodgett, MP (reprint author), USAF, Res Lab, Met Ceram & NDE Div, Wright Patterson AFB, OH 45433 USA. RI Nagy, Peter/O-5404-2016 OI Nagy, Peter/0000-0001-5715-2409 NR 0 TC 0 Z9 0 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-408-4 J9 MATER RES SOC SYMP P PY 1998 VL 503 BP 53 EP 62 PG 10 WC Engineering, Civil; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BL56M UT WOS:000075897100007 ER PT S AU Maji, AK AF Maji, AK BE Crane, RL Achenbach, JD Shah, SP Matikas, TE KhuriYakub, PT Gilmore, RS TI Evaluation of prestressing with a shape memory alloy SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IN AGING SYSTEMS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nondestructive Characterization of Materials in Aging Systems CY NOV 30-DEC 04, 1997 CL BOSTON, MA SP Mat Res Soc AB The paper addresses the possibility of using shape-memory effect in Nitinol (Nickel-Titanium) alloy to remedy prestress losses in aging concrete beams. Straight annealed NiTi in the low temperature martensite phase can undergo large plastic deformations, This deformation and strain energy is recoverable when the material transforms to the higher temperature (about 55 degrees C) austentite phase. This phenomena can be exploited to induce curvature, hence prestressing, by embedding NiTi wires and ropes in a structural member. Depending on the type of wire used its actuation effect can be reversed as necessary, creating the possibility of a smart prestressed concrete bridge of the future. Materials aspect studied in this project include the bond between NiTi wires and the host composite material, through mechanical testing and microscopy. An evaluation of the phase transformation is conducted using Acoustic Emission (AE) technology. AE event rate, locations and characteristics were evaluated during the actuation process. C1 USAF, Res Lab, VSDV, Kirtland AFB, NM 87117 USA. RP Maji, AK (reprint author), USAF, Res Lab, VSDV, Kirtland AFB, NM 87117 USA. NR 0 TC 2 Z9 2 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-408-4 J9 MATER RES SOC SYMP P PY 1998 VL 503 BP 287 EP 295 PG 9 WC Engineering, Civil; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BL56M UT WOS:000075897100039 ER PT S AU Evans, BL Martin, JB Burggraf, LW AF Evans, BL Martin, JB Burggraf, LW BE Crane, RL Achenbach, JD Shah, SP Matikas, TE KhuriYakub, PT Gilmore, RS TI Nondestructive inspection of thin, low-Z samples using multiplexed Compton scatter tomography SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IN AGING SYSTEMS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Nondestructive Characterization of Materials in Aging Systems CY NOV 30-DEC 04, 1997 CL BOSTON, MA SP Mat Res Soc AB The viability of a Compton scattering tomography system for nondestructively inspecting thin, low Z samples for corrosion is examined. This technique differs from conventional x-ray backscatter NDI because it does not rely on narrow collimation of source and detectors to examine small volumes in the sample. Instead, photons of a single energy are backscattered from the sample and their scattered energy spectra are measured st multiple detector locations, and these spectra are then used to reconstruct an image of the object. This multiplexed Compton scatter tomography technique interrogates multiple volume elements simultaneously. Thin samples less than 1 cm thick and made of low Z materials are best imaged with gamma rays at or below 100 keV energy. At this energy, Compton line broadening becomes an important resolution limitation. An analytical model has been developed to simulate the signals collected in a demonstration system consisting of an array of planar high-purity germanium detectors. A technique for deconvolving the effects of Compton broadening and detector energy resolution from signals with additive noise is also presented. A filtered backprojection image reconstruction algorithm with similarities to that used in conventional transmission computed tomography is developed. A simulation of a 360-degree inspection gives distortion-free results. In a simulation of a single-sided inspection, a 5 mm x 5 mm corrosion flaw with 508 density is readily identified in I-cm thick aluminum phantom when the signal to noise ratio in the data exceeds 28. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Evans, BL (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-408-4 J9 MATER RES SOC SYMP P PY 1998 VL 503 BP 297 EP 308 PG 12 WC Engineering, Civil; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BL56M UT WOS:000075897100040 ER PT S AU McCollum, SW Slattery, KT AF McCollum, SW Slattery, KT BE Doctor, SR Lebowitz, CA Baaklini, GY TI Structural damage monitoring in composite-confined concrete columns using Bragg gratings SO NONDESTRUCTIVE EVALUATION OF MATERIALS AND COMPOSITES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nondestructive Evaluation of Materials and Composites II CY MAR 31-APR 01, 1998 CL SAN ANTONIO, TX SP Soc Photo Opt Instrumentat Engineers, Fed Aviat Adm, Nondestruct Testing Informat Anal Ctr, Fed Highway Adm, Natl Inst Stand & Technol, Lawrence Livermore Natl Lab, Def Adv Res Projects Agcy, Soc Exptl Mech, Japan Soc Mech Engineers, Japanese Soc Nondestruct Inspect, USAF Res Lab, Pressure Vessel Res Council, Gas Res Inst, Amer Soc Nondestruct Testing DE Bragg gratings; confined concrete; strain gages; triaxial strain; micromechanical models AB Confinement of concrete columns for earthquake retrofit and new construction is being studied extensively and has been implemented in some applications. Large-scale, composite-confined concrete cylinders were tested to failure in compression to investigate scale effects on the response of the material, to allow more thorough instrumentation, and to study the feasibility of long-term monitoring of composite civil structures using embedded sensors. Bragg grating optical fiber strain gages were embedded in three hoop-wrapped, filament-wound, carbon/epoxy composite cylinders. Multiple optical fiber gages were placed in both the axial and circumferential directions. Resistive gages were placed near the optical fiber locations. The 12-inch diameter cylinders were filled with concrete and tested in axial compression. A triaxial state of strain was induced in the optical fibers - axial compression from the load, radial pressure from the expanding concrete, and circumferential tension to contain the radial pressure. The extensive data recorded in the optical fiber and resistive strain gages during compression loads to failure allowed a detailed study of transverse strain effects on Bragg gratings. Conventional mechanics of materials models and micromechanical finite element models were used to predict the relationship between surface strains measured by resistive gages and Bragg grating wavelength shifts. Various models were used to account for the effects of the three strain components on the response of the Bragg grating. Although the average error between resistive and optical fiber readings could be reduced by correcting for transverse strains, there were still significant differences (over 20%). The embedded optical fiber strain gages did provide a sufficiently repeatable and accurate measurement of strain in these structures for long-term damage monitoring or post-earthquake inspection. C1 27th Civil Engn Squadron, Cannon AFB, NM 88103 USA. RP McCollum, SW (reprint author), 27th Civil Engn Squadron, Cannon AFB, NM 88103 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 0-8194-2845-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3396 BP 14 EP 21 DI 10.1117/12.301522 PG 2 WC Materials Science, Ceramics; Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BK61L UT WOS:000072738100002 ER PT S AU McLean, DG AF McLean, DG BE Lawson, CM TI Concentration gradient limiter designs for incident plane waves and multiple chromophores SO NONLINEAR OPTICAL LIQUIDS FOR POWER LIMITING AND IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nonlinear Optical Liquids for Power Limiting and Imaging CY JUL 22, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE reverse saturable absorption; optical limiter; concentration gradient design; Lommel functions; top-hat beam ID OPTIMIZATION; ABSORPTION AB A design method for reverse saturable absorbing (RSA) dye concentration gradient limiters, termed here the Absorption Diffraction Balance (ADB) design method, is used to produce designs for multiple chromophores and is extended to allow incident plane waves. The ADB design method is reviewed for Gaussian beams applied to a constant fluence design and a linear fluence design. These two designs are combined to allow different dyes to be used in different portions of the limiter. It is found that this hybrid design significantly enhances performance under some circumstances. It is also shown to reduce the probability of dye photodegradation. The ADB design method is extended to allow for incident plane waves or a top-hat beam profile. The field at the geometric shadow edge, expressed in terms of Lommel functions, is shown to closely match the Gaussian field when the incident irradiance, power, and second moments are the same. Since the irradiance distribution is not monotonically increasing in the focal region, the required concentration distribution has regions of negative concentration, i.e. gain regions. These designs are useful for initiating numerical nonlinear beam propagation studies. C1 AFRL, MLPJ, Mat Directorate, Wright Patterson AFB, OH USA. RP McLean, DG (reprint author), AFRL, MLPJ, Mat Directorate, Wright Patterson AFB, OH 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 0-8194-2927-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3472 BP 62 EP 69 DI 10.1117/12.326873 PG 8 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BM32Z UT WOS:000078396600007 ER PT S AU Baur, JW Alexander, MD Banach, M Reinhardt, B Prasad, PN Yaun, LX Vaia, RA AF Baur, JW Alexander, MD Banach, M Reinhardt, B Prasad, PN Yaun, LX Vaia, RA BE Lawson, CM TI Influence of molecular environment on single photon behavior of heterocyclic NLO chromophores and its implications to two-photon behavior SO NONLINEAR OPTICAL LIQUIDS FOR POWER LIMITING AND IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nonlinear Optical Liquids for Power Limiting and Imaging CY JUL 22, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE two-photon absorbance; up-convert fluorescence; heterocyclic dyes; photoluminescence AB Over the past several years, organic molecules exhibiting significant two-photon absorbance have been of intense interest for a wide variety of applications including high speed communications, data storage, imaging, and optical limiting. However, it has been commonly observed that the local molecular environment can significantly affect the linear and nonlinear optical properties of the chromophores. In an effort to examine these effects, the influence of the solvent environment on the linear absorbance and photoluminescence of a series of donor-acceptor heterocyclic chromophores was examined. The Stoke's shift associated with one-photon absorbance and photoluminescence was observed to increase with increasing solvent polarity. This behavior is adequately described by the Lippert equation and is related to relaxation of the solvent molecules around an excited molecule. Additionally, it was observed that the spectral shape, as well as the solvent dependence, of two-photon and one-photon pumped photoluminescence were similar, thus indicating that the longest-lived luminescing excited state is independent of the method of excitation. These results have direct implications to two-photon applications which rely on up-converted fluorescence. They also yield insight into the structure-property relationships governing their linear and multi-photon behavior including the potential contributions to the effective two-photon cross-section from excited state absorbance. C1 USAF, Res Lab, Mat Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Baur, JW (reprint author), USAF, Res Lab, Mat Mfg Directorate, Wright Patterson AFB, OH 45433 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 0-8194-2927-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3472 BP 70 EP 79 DI 10.1117/12.326874 PG 10 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BM32Z UT WOS:000078396600008 ER PT S AU Fleitz, PA Brant, MC Sutherland, RL Strohkendl, FP Larsen, RJ Dalton, LR AF Fleitz, PA Brant, MC Sutherland, RL Strohkendl, FP Larsen, RJ Dalton, LR BE Lawson, CM TI Nonlinear measurements on AF-50 SO NONLINEAR OPTICAL LIQUIDS FOR POWER LIMITING AND IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nonlinear Optical Liquids for Power Limiting and Imaging CY JUL 22, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE AF-50; nonlinear absorption; two-photon absorption; optical limiting ID ISOTROPIC LIQUID-STATE; Z-SCAN MEASUREMENTS; 2-PHOTON ABSORPTION AB The nonlinear optical properties of N,N-diphenyl-7-[2-(4-pyridinyl) ethenyl]-9,9-di-n-decylfluoren-2-amine [AF-50] have been investigated. The nonlinear absorption of a saturated solution of this material in acetone was investigated with 430 femtosecond pulses at 790nm. From these results, the two-photon absorption cross-section was determined to be 25 x 10(-50) cm(4)sec/photon molecule. This number is in agreement (within a factor of 2) with theoretical calculations. Nonlinear absorption and optical limiting measurements were also made using a Nd:YAG pumped dye laser with 4.3ns pulses at 694nm. These results suggest inherent differences in the performance of two-photon absorbing materials in these two different geometries. C1 USAF, Res Lab, AFRL MLPJ, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Fleitz, PA (reprint author), USAF, Res Lab, AFRL MLPJ, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 14 TC 13 Z9 13 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 0-8194-2927-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3472 BP 91 EP 97 DI 10.1117/12.326876 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BM32Z UT WOS:000078396600010 ER PT S AU Su, WJ Cooper, TM Nguyen, K Brant, MC Brandelik, D McLean, DG AF Su, WJ Cooper, TM Nguyen, K Brant, MC Brandelik, D McLean, DG BE Lawson, CM TI Structure-optical property relationships of porphyrins SO NONLINEAR OPTICAL LIQUIDS FOR POWER LIMITING AND IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nonlinear Optical Liquids for Power Limiting and Imaging CY JUL 22, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE porphyrin; optical limiting; structure-property relationship ID NONLINEAR ABSORPTION; NONPLANAR AB Porphyrins are attractive compounds for optical applications. We have been investigating the relationship between molecular structure and optical properties of a number of poryhyrin compounds. Structural variations explored include insertion of metal ions, extension of conjugation, halogenation and alkylation either at the pyrrole position or the meso-aryl groups. The characterization of these chromophores includes measurement of UV/Vis, fluorescence and fluorescence lifetimes. Furthermore, we have investigated their nonlinear absorption, excitation dynamics. The significant factors influencing limiting behavior appear to be the heavy atom effect, electron donating and withdrawing substituents conformation distortion and changes in conjugation. Detailed understanding will be gained from measurements of photophysical parameters underlying limiting behavior. C1 Wright Lab, WL MLPJ, Wright Patterson AFB, OH 45433 USA. RP Su, WJ (reprint author), Wright Lab, WL MLPJ, 3005 P St Ste 1, Wright Patterson AFB, OH 45433 USA. NR 14 TC 9 Z9 9 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 0-8194-2927-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3472 BP 136 EP 143 DI 10.1117/12.326881 PG 8 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BM32Z UT WOS:000078396600015 ER PT S AU Jiang, H DeRosa, M Su, WJ Brant, M McLean, D Bunning, T AF Jiang, H DeRosa, M Su, WJ Brant, M McLean, D Bunning, T BE Lawson, CM TI Polymer host materials for optical limiting SO NONLINEAR OPTICAL LIQUIDS FOR POWER LIMITING AND IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Nonlinear Optical Liquids for Power Limiting and Imaging CY JUL 22, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE optical limiting; polymer elastomers; hydrogels; laser damage threshold; molecular flexibility; thermomechanical fracture; molecular mobility; laser energy dissipation; self-healing ID GEL; WATER AB Two polymer systems including polymer elastomers and gels have been studied as host materials for optical limiting applications. Both systems have high laser damage thresholds (LDT), typically 20 to 35 times higher than commercial PMMA bulk materials. For the polymer elastomers, Epotek optical epoxy 301-2 and 310, the LDT increases with an increase of the molecular flexibility. We speculate that the thermo-mechanical fracture may be the mechanism for the laser induced damage. For the hydrogel system, the LDT increases with increasing water content. The mobility of the water plays a key role in determining the LDT by facilitating laser energy dissipation and self-healing. It appears that the polymer elastomer and hydrogel systems both have potential for high power laser applications. C1 AFRL, MLPJ, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Jiang, H (reprint author), AFRL, MLPJ, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 24 TC 3 Z9 3 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2927-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3472 BP 157 EP 162 DI 10.1117/12.326885 PG 6 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BM32Z UT WOS:000078396600018 ER PT S AU Marker, DK Carreras, RA Wilkes, JM Jenkins, CH Duneman, D Rotge, JR Hogge, CB AF Marker, DK Carreras, RA Wilkes, JM Jenkins, CH Duneman, D Rotge, JR Hogge, CB BE Bell, KD Powers, MK Sasian, JM TI Optical evaluation of membrane mirrors with curvature SO NOVEL OPTICAL SYSTEMS AND LARGE-APERTUR IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Novel Optical Systems and Large-Aperture Imaging CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE membrane optics; optical quality reflectors; thin films; reflectors; inflatable; solar collectors AB Thin membranes with curvature are investigated as mirror substrates for use in large optical telescopes. These films are mounted on an optically flat circular ring and stretched over a smaller optically flat circular ring where pressure or vacuum is applied to create the doubly curved surface as shown in figure 1. The films may vary in thickness from 20 to 200 microns. This particular experiment examines an aluminum coated 125 micron thick homogeneous, planar, isotropic membrane with a clear aperture of 28 centimeters. The nature of a flexible membrane implies that the surface curvature will result in an assorted array of gross surface figure issues associated with deterministic shape limits, probabilistic imperfections, nonlinear constitutive effects, and long-time-dependent effects. This report will focus on the empirical deterministic shape limits of a doubly curved membrane. Theoretical work on thin films inflated or evacuated into a doubly curved surface has a long history, and remains an active area of research. A number of articles[1,2,3,4,7] include summaries of this history, and offer insight on the deterministic membrane shapes. C1 USAF, Res Lab, Adv Opt & Imaging Div, Kirtland AFB, NM 87117 USA. RP Marker, DK (reprint author), USAF, Res Lab, Adv Opt & Imaging Div, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 7 TC 7 Z9 7 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 0-8194-2885-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3430 BP 202 EP 208 DI 10.1117/12.332489 PG 7 WC Optics SC Optics GA BM32M UT WOS:000078391400020 ER PT S AU Griffin, S Robertson, LR Huybrechts, S AF Griffin, S Robertson, LR Huybrechts, S BE Bell, KD Powers, MK Sasian, JM TI Ultra-lightweight structures for deployed optics SO NOVEL OPTICAL SYSTEMS AND LARGE-APERTUR IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Novel Optical Systems and Large-Aperture Imaging CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE composite structures; vibration isolation AB The optical support boom and related facilities for the Ultra-Lightweight Imaging Technology Experiment (UltraLITE) program at the US Air Force Research Laboratory are described in this paper as well as the implementation of a local feedback loop to control the boom's first bending mode. The primary goal of the efforts described in this paper are to provide a relatively quiet vibration environment for optical active control experiments to be performed on the deployable optical support boom. The optical active control experiments to date are described in a companion paper(1). C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Griffin, S (reprint author), USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. NR 4 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 0-8194-2885-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3430 BP 219 EP 226 DI 10.1117/12.332488 PG 8 WC Optics SC Optics GA BM32M UT WOS:000078391400022 ER PT S AU Leitner, J Denoyer, K AF Leitner, J Denoyer, K BE Bell, KD Powers, MK Sasian, JM TI Model inversion tracking control for UltraLITE using neural networks SO NOVEL OPTICAL SYSTEMS AND LARGE-APERTUR IMAGING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Novel Optical Systems and Large-Aperture Imaging CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn AB This paper presents the analytical methodology and initial numerical simulation results for autonomous neural control of the Ultra-Lightweight Imaging Technology Experiments (UltraLITE) Phase I test article. The UltraLITE Phase I test article is a precision deployable structure currently under development at the United States Air Force Research Laboratory (AFRL). Its purpose is to examine control and hardware integration issues related to large deployable sparse optical array spacecraft systems. In this paper, a multi-stage control architecture is examined which incorporates artificial neural networks for model inversion tracking control. The emphasis in the control design approach is to exploit the known nonlinear dynamics of the system in the synthesis of a model inversion tracking controller and to augment the nonlinear controller with an adaptive neuro-controller to accommodate for changing dynamics, failures, and model uncertainties. C1 USAF, Res Lab, AFRLVS, Kirtland AFB, NM 87117 USA. RP Leitner, J (reprint author), USAF, Res Lab, AFRLVS, 3550 Aberdeen Ave SE, 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 0-8194-2885-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3430 BP 227 EP 235 DI 10.1117/12.332478 PG 9 WC Optics SC Optics GA BM32M UT WOS:000078391400023 ER PT J AU Jessup, JP Vandewalle, KS Hermesch, CB Buikema, DJ AF Jessup, JP Vandewalle, KS Hermesch, CB Buikema, DJ TI Effects of surface treatments on amalgam repair SO OPERATIVE DENTISTRY LA English DT Article ID HIGH-COPPER AMALGAM; BOND STRENGTH; FLEXURAL STRENGTH AB Dentists are faced with clinical situations that require the decision to replace or repair an amalgam restoration. The purpose of this study was to compare five amalgam repair techniques. Six groups of 15 amalgam beams each were fabricated by mechanical condensation of Tytin into an anodized aluminum split mold. Specimens were aged for 7 days prior to repair. Repaired specimens were stored for 7 days and thermocycled 500 times. Repair strength was measured by transverse strength testing in an Instron testing machine. Data were analyzed by a one-way ANOVA and a Student-Newman-Keuls test at the P less than or equal to 0.05 level. The surface treatments were: Group A) intact beams, B) roughened with a #557 bur, C) air abraded with 50 mu m aluminum oxide, D) retentive undercuts with a #33 1/2 bur, E) Amalgambond Plus, and F) no treatment. The repair strength of the various experimental groups ranged from 7-18% of the intact specimens. The #557 bur-roughened group yielded statistically higher repair strengths than all other surface treatments, which were statistically equivalent to each other. C1 Dunn Dent Clin, Dept Gen Dent, Lackland AFB, TX 78236 USA. RP Jessup, JP (reprint author), Dunn Dent Clin, Dept Gen Dent, Bldg 6418,1615 Truemper St, Lackland AFB, TX 78236 USA. NR 24 TC 12 Z9 13 U1 0 U2 0 PU UNIV WASHINGTON PI SEATTLE PA SCHOOL DENTISTRY SM-57, SEATTLE, WA 98195 USA SN 0361-7734 J9 OPER DENT JI Oper. Dent. PD JAN-FEB PY 1998 VL 23 IS 1 BP 15 EP 20 PG 6 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA YM602 UT WOS:000071081200004 PM 9610328 ER PT S AU Wright, CHG Oberg, ED Barrett, SF AF Wright, CHG Oberg, ED Barrett, SF BE Rol, PO Joos, KM Manns, F TI Hybrid retinal tracking and coagulation system SO OPHTHALMIC TECHNOLOGIES VIII, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Ophthalmic Technologies VIII CY JAN 24-25, 1998 CL SAN JOSE, CA SP USAF, Off Sci Res, Int Biomed Opt Soc, Soc Photo Opt Instrumentat Engineers DE retinal surgery; diabetic retinopathy; automated surgery; reflectance; argon laser; retinal tracking AB Laser photocoagulation is used extensively by ophthalmologists to treat retinal disorders such as diabetic retinopathy and retinal breaks and tears. Currently, the procedure is performed manually and suffers from several drawbacks: it often requires many clinical visits, it is very tedious for both patient and physician, the laser pointing accuracy and safety margin are limited by a combination of the physician's manual dexterity and the patient's ability to hold their eye still, and there is a wide variability in retinal tissue absorption parameters. A computer-assisted hybrid system is under development that will rapidly and safely place multiple therapeutic lesions at desired locations on the retina in a matter of seconds. In the past, one of the main obstacles to such a system has been the ability to track the retina and compensate for any movement with sufficient speed during photocoagulation. Two different tracking modalities (digital image-based tracking and analog confocal tracking) were designed and tested in vivo on pigmented rabbits. These two systems are being seamlessly combined into a hybrid system which provides real-time, motion stabilized lesion placement for typical irradiation times (100 ms). This paper will detail the operation of the hybrid system and efforts toward controlling the depth of coagulation on the retinal surface. C1 USAF Acad, Dept Elect Engn, Colorado Springs, CO 80840 USA. RP Wright, CHG (reprint author), USAF Acad, Dept Elect Engn, 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 0-8194-2685-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3246 BP 185 EP 191 DI 10.1117/12.309430 PG 7 WC Engineering, Biomedical; Ophthalmology; Optics SC Engineering; Ophthalmology; Optics GA BL20A UT WOS:000074660600022 ER PT S AU Kervin, PW Nishimoto, DL Sydney, PF Africano, JL Hoo, VS Talent, DL Fricke, GJ Angara, AF O'Connell, DG Africano, BM AF Kervin, PW Nishimoto, DL Sydney, PF Africano, JL Hoo, VS Talent, DL Fricke, GJ Angara, AF O'Connell, DG Africano, BM BE DOdorico, S TI Raven concept applied to asteroid and satellite surveillance SO OPTICAL ASTRONOMICAL INSTRUMENTATION, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Optical Astronomical Instrumentation Conference CY MAR 26-28, 1998 CL KONA, HI SP SPIE, European So Observ, Amer Astron Soc, Astron Soc Pacific, Canadian Astron Soc DE Raven; small telescopes; space surveillance; asteroids; satellites; autonomous; astrometry; AFRL AB Not all realms of observation require an 8-meter telescope. Some, such as space surveillance of asteroids and man-made satellites, are too important to ignore, yet obviously inappropriate to consign to the new generation of large telescopes. The United States Air Force Research Laboratory (AFRL), with Boeing, Rocketdyne Technical Services (RTS), has developed a low-cost, rapidly deployable surveillance telescope concept called Raven which takes advantage of commercial off-the-shelf (COTS) telescopes, detectors, and software. The development of the Raven concept was originally a response to a recognized need to support the timely follow-up of asteroid discoveries. Early astrometric tests using Raven telescope in the 12- to 16-inch diameter range proved to be comparable in accuracy to the much larger telescopes of the existing space surveillance network. Observations of man-made satellites have also produced quality results. A high level of productivity is achieved by automating all of the observing functions and much of the data reduction and analysis. Performance data in both the areas of asteroid and satellite metrics will be presented, and performance parameters discussed. C1 USAF, Res Lab, Kihei, HI 96753 USA. RP Kervin, PW (reprint author), USAF, Res Lab, 535 Lipoa Pkwy, Kihei, HI 96753 USA. NR 0 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 0-8194-2802-7 J9 P SOC PHOTO-OPT INS PY 1998 VL 3355 BP 734 EP 740 PN 1-2 PG 4 WC Astronomy & Astrophysics; Instruments & Instrumentation; Remote Sensing; Optics SC Astronomy & Astrophysics; Instruments & Instrumentation; Remote Sensing; Optics GA BL41A UT WOS:000075411500076 ER PT S AU Johnson, WE Edmonds, BP Wolf, MJ AF Johnson, WE Edmonds, BP Wolf, MJ BE Datla, RV Hanssen, LM TI Environmental stability of rugate filters: in-situ measurements of their spectral properties SO OPTICAL DIAGNOSTIC METHODS FOR INORGANIC TRANSMISSIVE MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostic Methods for Inorganic Transmissive Materials CY JUL 20-21, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE optical; coating; rugate; deposition processes; reflection; environmental chamber; relative humidity; in-situ; spectral shift AB Historically, the optical coating community has greatly improved the environmental stability of single and multilayer coatings through the incorporation of energetic processes into the deposition chamber. Typically three different methods are used to impart additional kinetic energy: 1) to the evaporant at the source, 2) to the evaporant while in route between the source and substrate, or 3) to the condensate at the substrate. One of the benefits of these energetic processes is the reduction of the spectral shift of the filter with changes in relative humidity. Typical spectral shifts can range from tens of nanometers with nonenergetic processes to less than tenths of a nanometer with energetic processes. This paper contrasts in-situ measured spectral shifts over the visible wavelength region of single narrow reflection band rugate coatings placed in an environmental chamber. Measurements were taken at room temperature while incrementally increasing the relative humidity from less than 2 to 90%. The measured rugate coatings were fabricated by three different processes: physical vapor deposition, ion-assisted physical vapor deposition, and sputtering. The spectral shift of the reflection band for the physical vapor deposition coating was 24.7 nanometers, as measured at the full-width-at-half maximum, and for the two more energetic process coatings less than 2.6 Angstroms, the resolution of our measurement. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Johnson, WE (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 4 Z9 4 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 0-8194-2880-9 J9 P SOC PHOTO-OPT INS PY 1998 VL 3425 BP 85 EP 91 DI 10.1117/12.326682 PG 7 WC Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BM03R UT WOS:000077457500010 ER PT J AU Alam, MS Khoury, JS AF Alam, MS Khoury, JS TI Fringe-adjusted incoherent erasure joint transform correlator SO OPTICAL ENGINEERING LA English DT Article DE recognition techniques; photorefractive media; fringe-adjusted joint transform correlator; joint power spectrum; pattern recognition; optical correlation; four-wave mixing; incoherent erasure ID FOURIER-TRANSFORM AB A new all-optical nonlinear fringe-adjusted joint transform correlation (JTC) technique is proposed. The proposed scheme is based on incoherent-to-coherent conversion with the erasure of a four-wave mixing arrangement in a real-time photorefractive media. This technique is very fast because it generates the correlation output in one step and all intermediate processing is performed in the optical domain. Furthermore, this technique eliminates the problems due to nonlinearities associated with the square-law devices and spatial light modulators used for recording the joint power spectrum. Computer simulation results show that the proposed joint transform correlator yields superior performance when compared to the alternative joint transform correlator architectures. (C) 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)02001-7]. C1 Purdue Univ, Dept Elect Engn, Ft Wayne, IN 46805 USA. Indiana Univ, Grad Fac, Bloomington, IN 47405 USA. Lartec Inc, Concord, NH 03301 USA. USAF, Rome Lab, Medford, MA 01731 USA. RP Alam, MS (reprint author), Purdue Univ, Dept Elect Engn, ET 327A,2101 Coliseum Blvd E, Ft Wayne, IN 46805 USA. EM alam@engr.ipfw.edu NR 24 TC 26 Z9 26 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 JAN PY 1998 VL 37 IS 1 BP 75 EP 82 DI 10.1117/1.601828 PG 8 WC Optics SC Optics GA YV001 UT WOS:000071778500013 ER PT J AU Hardie, RC Barnard, KJ Bognar, JG Armstrong, EE Watson, EA AF Hardie, RC Barnard, KJ Bognar, JG Armstrong, EE Watson, EA TI High-resolution image reconstruction from a sequence of rotated and translated frames and its application to an infrared imaging system SO OPTICAL ENGINEERING LA English DT Article DE high resolution; image reconstruction; aliasing; infrared; Nyquist; minimization ID RESTORATION; REDUCTION AB Some imaging systems employ detector arrays that are not sufficiently dense to meet the Nyquist criterion during image acquisition. This is particularly true for many staring infrared imagers. Thus, the full resolution afforded by the optics is not being realized in such a system. This paper presents a technique for estimating a high-resolution image, with reduced aliasing, from a sequence of undersampled rotated and translationally shifted frames. Such an image sequence can be obtained if an imager is mounted on a moving platform, such as an aircraft. Several approaches to this type of problem have been proposed in the literature. Here we extend some of this previous work. In particular, we define an observation model that incorporates knowledge of the optical system and detector array. The high-resolution image estimate is formed by minimizing a regularized cost function based on the observation model. We show that with the proper choice of a tuning parameter, our algorithm exhibits robustness in the presence of noise. We consider both gradient descent and conjugate-gradient optimization procedures to minimize the cost function. Detailed experimental results are provided to illustrate the performance of the proposed algorithm using digital video from an infrared imager. (C) 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)03401-1]. C1 Univ Dayton, Dept Elect & Comp Engn, Dayton, OH 45469 USA. USAF, Wright Lab, Electroopt Sensor Technol Branch, Dayton, OH 45433 USA. Technol Sci Serv Inc, Dayton, OH 45437 USA. RP Hardie, RC (reprint author), Univ Dayton, Dept Elect & Comp Engn, Dayton, OH 45469 USA. NR 21 TC 218 Z9 242 U1 2 U2 9 PU SPIE - INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING PI BELLINGHAM PA POB 10, BELLINGHAM, WA 98227-0010 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD JAN PY 1998 VL 37 IS 1 BP 247 EP 260 DI 10.1117/1.601623 PG 14 WC Optics SC Optics GA YV001 UT WOS:000071778500036 ER PT S AU Goldstein, DH Mills, SA Dydyk, RB AF Goldstein, DH Mills, SA Dydyk, RB BE Casasent, DP Chao, TH TI Use of laser radar imagery in optical pattern recognition: the optical processor enhanced ladar (OPEL) program SO OPTICAL PATTERN RECOGNITION IX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Pattern Recognition IX CY APR 14-15, 1998 CL ORLANDO, FL SP SPIE, Int Soc Opt Engn DE laser radar; ladar; optical correlation; optical processing; optical pattern recognition; seeker AB The Optical Processor Enhanced Ladar (OPEL) program is designed to evaluate the capabilities of a seeker obtained by integrating two state-of-the-art technologies, laser radar, or ladar, and optical correlation. The program is a thirty-two month effort to build, optimize, and test a breadboard seeker system (the OPEL System) that incorporates these two promising technologies. Laser radars produce both range and intensity image information. Use of this information in an optical correlator is described. A correlator with binary phase input and ternary amplitude and phase filter capability is assumed. Laser radar imagery was collected on five targets over 360 degrees of azimuth from 3 elevation angles. This imagery was then processed to provide training sets in preparation for filter construction. This paper reviews the ladar and optical correlator technologies used, outlines the OPEL program, and describes the OPEL system. C1 USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. RP Goldstein, DH (reprint author), USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. NR 0 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 0-8194-2835-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3386 BP 389 EP 400 DI 10.1117/12.304787 PG 12 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BK81F UT WOS:000073468900042 ER PT S AU Stein, C King, TR Wilson, WG Robertson, R AF Stein, C King, TR Wilson, WG Robertson, R BE Chen, PT McClintock, WE Rottman, GJ TI Spacecraft contamination, active cleaning and control SO OPTICAL SYSTEMS CONTAMINATION AND DEGRADATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Systems Contamination and Degradation CY JUL 20-23, 1998 CL SAN DIEGO, CA SP SPIE Int Soc Opt Engn DE spacecraft contamination; atomic oxygen; spacecraft charging; passive cleaning method AB Critical surfaces on satellites operating in the Low Earth Orbit (LEO) can be contaminated by molecular species emanating from the spacecraft itself and from hypervelocity debris impacts. Consequently, onboard procedures are necessary to limit the contamination to levels below specified thicknesses in order to achieve the operational requirements of solar panels, thermal management materials, thermal radiators and optical systems. We demonstrate that our recently discovered phenomenon of the acceleration of the atomic oxygen erosion of organic molecular species by the simultaneous super-position of an electrostatic charge on the substrate, can be used to clean organic contaminants off critical surfaces in space. C1 USAF, Res Lab, Space Vehicle Directorate, VSSE, Kirtland AFB, NM 87117 USA. RP Stein, C (reprint author), USAF, Res Lab, Space Vehicle Directorate, VSSE, 2050 Chanute St, Kirtland AFB, NM 87117 USA. NR 0 TC 2 Z9 3 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 0-8194-2882-5 J9 P SOC PHOTO-OPT INS PY 1998 VL 3427 BP 56 EP 64 DI 10.1117/12.328520 PG 9 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BM07P UT WOS:000077549100006 ER PT S AU Ratkowski, AJ Anderson, GP Chetwynd, JH Nadile, RM Devir, AD Conley, TD AF Ratkowski, AJ Anderson, GP Chetwynd, JH Nadile, RM Devir, AD Conley, TD BE Kohnle, A Devir, AD TI A comparison of atmospheric transmittance measurements in the 3-5 mu m and 8-12 mu m spectral regions with MODTRAN: considerations for long near-horizontal path geometries SO OPTICS IN ATMOSPHERIC PROPAGATION AND ADAPTIVE SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optics in Atmospheric Propagation and Adaptive Systems II CY SEP 23-24, 1997 CL LONDON, ENGLAND SP CNR, NASA, European Opt Soc, Soc Photo Opt Instrumentat Engineers, Commiss Europena Communities, Directorate Gen Sci Res & Dev AB Radiance measurements conducted during tropospheric operations to detect objects on the Earth's surface from a manned aircraft or from an unmanned airborne vehicle (UAV) will involve long, near-horizontal viewing geometries. The computer code MODTRAN is widely used for the prediction of the propagation of infrared radiation through the lower atmosphere. Consequently, we have undertaken to test the predictions of MODTRAN for the 3-5 and 8-12 micron spectral regions under mid-Eastern desert conditions. C1 USAF, Phillips Lab, Opt Effects Div PL GPO, Hanscom AFB, MA 01731 USA. RP Ratkowski, AJ (reprint author), USAF, Phillips Lab, Opt Effects Div PL GPO, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 0 TC 1 Z9 1 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 0-8194-2651-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3219 BP 2 EP 10 DI 10.1117/12.298049 PG 9 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BK46D UT WOS:000072275300001 ER PT S AU Matson, CL Holland, D Pierrottet, D Ruffatto, D Czyzak, SR Mosley, D AF Matson, CL Holland, D Pierrottet, D Ruffatto, D Czyzak, SR Mosley, D BE Kohnle, A Devir, AD TI Satellite feature reconstruction using reflective tomography - field results SO OPTICS IN ATMOSPHERIC PROPAGATION AND ADAPTIVE SYSTEMS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optics in Atmospheric Propagation and Adaptive Systems II CY SEP 23-24, 1997 CL LONDON, ENGLAND SP CNR, NASA, European Opt Soc, Soc Photo Opt Instrumentat Engineers, Commiss Europena Communities, Directorate Gen Sci Res & Dev DE laser radar; ladar; reflective tomography AB The Air Force Phillips Laboratory is in the process of demonstrating an advanced space surveillance capability with a heterodyne laser radar system to be used, among other applications, for range-resolved imaging of orbiting satellites. In this paper, we present our first satellite feature reconstruction from field results using reflective tomographic techniques. C1 USAF, Phillips Lab, Opt Sensing Div, Kirtland AFB, NM 87117 USA. RP Matson, CL (reprint author), USAF, Phillips Lab, Opt Sensing Div, Kirtland AFB, NM 87117 USA. NR 0 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 0-8194-2651-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3219 BP 65 EP 72 DI 10.1117/12.298050 PG 8 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BK46D UT WOS:000072275300008 ER PT S AU Grote, JG Drummond, JP AF Grote, JG Drummond, JP BE Chavel, P Miller, DAB Thienpont, H TI Novel nonlinear optical polymer opto-electronic devices SO OPTICS IN COMPUTING 98 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Optics in Computing 98 Meeting CY JUN 17-20, 1998 CL BRUGGE, BELGIUM SP European Opt Soc, Int Commiss Opt, IEEE, Lasers & Electro Opt Soc, Opt Soc Amer, Int Soc Opt Engn, USAF, European Off Aerosp Res & Dev, Newport, Melles Griot, Optilas, SCK CEN, Vrije Univ Brusell AB Presented is a novel design for opto-electronic integrated optic devices utilizing a nonlinear optical polymer core and conductive polymer claddings that will potentially have an order of magnitude shorter interaction length than conventional NLO polymer OE devices operating at TTL voltage levels and allows for in-situ poling. C1 WL AADO, Air Force Res Lab, Wright Patterson AFB, OH 45433 USA. RP Grote, JG (reprint author), WL AADO, Air Force Res Lab, Bldg 620,2241 Avionics Circle,Suite 20, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2949-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3490 BP 326 EP 330 DI 10.1117/12.308954 PG 3 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Optics SC Computer Science; Optics GA BL16G UT WOS:000074523000076 ER PT J AU Hohl, A Gavrielides, A Li, H AF Hohl, A Gavrielides, A Li, H TI Stable high-speed polarization switching in vertical cavity surface emitting lasers (VCSELs) SO OPTICS & PHOTONICS NEWS LA English DT Proceedings Paper CT Optical Amplifiers and Their Applications Topical Meeting CY JUL 21-23, 1997 CL VICTORIA, CANADA C1 Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87131 USA. USAF, Phillips Lab, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. RP USAF, Phillips Lab, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1047-6938 EI 1541-3721 J9 OPT PHOTONICS NEWS JI Opt. Photonics News PD JAN PY 1998 VL 9 IS 1 BP 47 EP 48 PG 2 GA YV592 UT WOS:000071841900022 ER PT S AU Lott, JA Noble, MJ Loehr, JP Ledentsov, NN Ustinov, VM Bimberg, D AF Lott, JA Noble, MJ Loehr, JP Ledentsov, NN Ustinov, VM Bimberg, D BE Osinski, M Su, YK TI Measurement of resonant-mode blueshifts in quantum dot vertical cavity surface emitting lasers SO OPTOELECTRONIC MATERIALS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Optoelectronic Materials and Devices CY JUL 09-11, 1998 CL TAIPEI, TAIWAN SP SPIE, Taiwan Chapter, Photon Ind Dev Assoc, Natl Sci Council, Taiwan DE vertical cavity surface emitting lasers; quantum dots; microcavities AB We experimentally investigate the modal properties of vertical cavity surface emitting lasers with vertically coupled quantum dot active regions. Etched air-post structures with aluminum-gallium-oxide apertures and aluminum-oxide distributed Bragg reflectors are electrically-pumped below the lasing threshold. The wavelengths of the resonant cavity modes are revealed by room temperature electroluminescence measurements. In concert with our earlier theoretical predictions, we find that the resonant cavity modes blueshift as the radius of the oxide aperture decreases. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Lott, JA (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2873-6 J9 P SOC PHOTO-OPT INS PY 1998 VL 3419 BP 208 EP 211 DI 10.1117/12.311011 PG 4 WC Optics SC Optics GA BL85U UT WOS:000076961400027 ER PT S AU Schwab, JJ Lichtenhan, JD Chaffee, KP Mather, PT Romo-Uribe, A AF Schwab, JJ Lichtenhan, JD Chaffee, KP Mather, PT Romo-Uribe, A BE Laine, RM Sanchez, C Brinker, CJ Giannelis, E TI Polyhedral Oligomeric Silsesquioxanes (POSS): Silicon based monomers and their use in the preparation of hybrid polyurethanes SO ORGANIC/INORGANIC HYBRID MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Organic/Inorganic Hybrid Materials at the 1998 MRS Spring Meeting CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Materials Res Soc (MRS) AB A series of Polyhedral Oligomeric Silsesquioxane (POSS) monomers bearing reactive hydroxyl functionalities, suitable for incorporation into step-growth polymers, is described. These monomers are difunctional in nature and are particularly well suited for use as chain extenders in the synthesis of polyurethanes. This work describes the synthesis of these POSS monomers and their incorporation into a series of polyurethanes. Preliminary thermal, mechanical and rheological data for the POSS containing polyurethanes will also be discussed. C1 USAF, Res Lab, Raytheon STX, Edwards AFB, CA 93524 USA. RP Schwab, JJ (reprint author), USAF, Res Lab, Raytheon STX, Edwards AFB, CA 93524 USA. NR 0 TC 17 Z9 18 U1 0 U2 7 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-425-4 J9 MATER RES SOC SYMP P PY 1998 VL 519 BP 21 EP 27 PG 7 WC Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary; Materials Science, Biomaterials; Materials Science, Composites SC Chemistry; Materials Science GA BM12K UT WOS:000077686600003 ER PT S AU Vaia, RA Lee, JW Click, W Price, G Wang, CS AF Vaia, RA Lee, JW Click, W Price, G Wang, CS BE Laine, RM Sanchez, C Brinker, CJ Giannelis, E TI Polymeric based conducting nanocomposites: Controlling the distribution of the conducting phase SO ORGANIC/INORGANIC HYBRID MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Organic/Inorganic Hybrid Materials at the 1998 MRS Spring Meeting CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Materials Res Soc (MRS) AB The optimization of bulk properties of polymeric based nano- and mesoscale composites require the ability to spatially control phase distribution. In this study, electrical conductivity is introduced by incorporation of a metal precursor via infiltration into the polymer host and subsequent conversion in-situ by a reducing agent, templating the morphology of the polymer matrix. Distribution of nano- and mesoscale metal particles in isotropic and anisotropic swollen polymer hosts is discussed relative to metal precursor and reducing reagent diffusion and their insitu bimolecular reduction reaction. The swelling and infiltration procedure employed to form the composites is generally applicable to rigid-rod, semi-flexible and flexible polymer matrices and not restricted to special synthesis of metal containing or complexing polymers. As an example, highperformance rigid-rod polymer fibers containing an interpenetrating network of polymer microfibrils and silver are produced with d.c. conductivities in excess of 10(4) S/cm and tensile strength at least 200 times that of pure silver. C1 USAF, Mat Directorate, AFRL, MLBP, Wright Patterson AFB, OH 45433 USA. RP Vaia, RA (reprint author), USAF, Mat Directorate, AFRL, MLBP, Bldg 654,2941 P St, Wright Patterson AFB, OH 45433 USA. NR 0 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 1-55899-425-4 J9 MATER RES SOC SYMP P PY 1998 VL 519 BP 201 EP 209 PG 9 WC Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary; Materials Science, Biomaterials; Materials Science, Composites SC Chemistry; Materials Science GA BM12K UT WOS:000077686600024 ER PT S AU Zelmon, DE Gebeyehu, Z Tomlin, D Cooper, TM AF Zelmon, DE Gebeyehu, Z Tomlin, D Cooper, TM BE Laine, RM Sanchez, C Brinker, CJ Giannelis, E TI Investigation of transition metal-xanthate complexes for nonlinear optical applications SO ORGANIC/INORGANIC HYBRID MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Organic/Inorganic Hybrid Materials at the 1998 MRS Spring Meeting CY APR 13-17, 1998 CL SAN FRANCISCO, CA SP Materials Res Soc (MRS) AB We have synthesized several metal xanthate complexes from metal salts and xanthate potassium salts. Powders of several of the materials were sorted and tested for their nonlinear optical properties. Cadmium xanthate demonstrated phase matchability for frequency doubling of 1.06 micron light and generated a very strong second harmonic signal. C1 USAF, Res Lab, Mat Directorate, AFRL,MLPO, Wright Patterson AFB, OH 45433 USA. RP Zelmon, DE (reprint author), USAF, Res Lab, Mat Directorate, AFRL,MLPO, Wright Patterson AFB, OH 45433 USA. NR 0 TC 13 Z9 15 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-425-4 J9 MATER RES SOC SYMP P PY 1998 VL 519 BP 395 EP 400 PG 6 WC Chemistry, Inorganic & Nuclear; Materials Science, Multidisciplinary; Materials Science, Biomaterials; Materials Science, Composites SC Chemistry; Materials Science GA BM12K UT WOS:000077686600051 ER PT S AU Bliznyuk, VN Campbell, A Tsukruk, VV AF Bliznyuk, VN Campbell, A Tsukruk, VV BE Frank, CW TI Organized multilayer films of charged organic latexes SO ORGANIC THIN FILMS: STRUCTURE AND APPLICATIONS SE ACS SYMPOSIUM SERIES LA English DT Article; Proceedings Paper CT Symposium on Organic Thin Films held at the 213th National Meeting of the American-Chemical-Society CY APR 13-17, 1997 CL SAN FRANCISCO, CALIFORNIA SP Amer Chem Soc ID ATOMIC-FORCE MICROSCOPY; SUPRAMOLECULAR POLYMERS; NATURAL LITHOGRAPHY; ULTRATHIN-FILM; PARTICLES; HETEROSTRUCTURES; NANOPARTICLES; DEPOSITION; DENDRIMERS; PORPHYRIN AB We study several multilayer latex-latex films fabricated by electrostatic self-assembly and composed of charged polystyrene (PS) latexes by combined scanning probe microscopy and X-ray reflectivity. PS nanoparticles of 20 - 200 nm in diameter possess carboxy, sulphate, and amidine surface groups. Most of latexes used are able to form monolayers with short-range local ordering of nanoparticles within the monolayer. Layer-by-layer deposition of latexes with alternating charges results in steady increase of film thickness that is consistent with dense centered cubic packing of nanospheres up to the first five layers. Virtually linear growth of film thickness is observed for further deposition (up to 50 layers) with average increment of 7.3 nm per layer for 20 nm nanoparticles due to the incomplete monolayer formation. During thermal treatment in a wide range of temperatures, we observe that strong tethering of charged nanoparticles to surfaces prevents their surface diffusion and rearrangements required for formation of perfect lateral ordering. C1 Western Michigan Univ, Coll Engn & Appl Sci, Kalamazoo, MI 49008 USA. USAF, Wright Lab, MLPJ, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Natl Acad Sci Ukraine, Inst Semicond Phys, UA-252143 Kiev, Ukraine. RP Bliznyuk, VN (reprint author), Western Michigan Univ, Coll Engn & Appl Sci, Kalamazoo, MI 49008 USA. NR 35 TC 8 Z9 8 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 SIXTEENTH ST NW, WASHINGTON, DC 20036 USA SN 0097-6156 BN 0-8412-3564-3 J9 ACS SYM SER PY 1998 VL 695 BP 220 EP 232 PG 13 WC Chemistry, Multidisciplinary; Chemistry, Organic; Materials Science, Multidisciplinary; Polymer Science SC Chemistry; Materials Science; Polymer Science GA BQ26Q UT WOS:000087751800016 ER PT J AU Thiringer, JK Arriaga, MA AF Thiringer, JK Arriaga, MA TI Stapedectomy in military aircrew SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 18-21, 1994 CL SAN DIEGO, CALIFORNIA SP Amer Acad Otolaryngol Head & Neck Surg ID REVISION AB Stapedectomy in military aircrew is generally considered to be the end of an aviation career, Perilymphatic fistulae, prosthesis dislodgement, and perforation of the vestibule are recognized complications of stapedectomy. Consequently, barotrauma, G forces, and otherwise hostile conditions and their effects on the poststapedectomy ear are usually cited as reasons for grounding, Data supporting such a restrictive policy, however, are limited, This study examined the aeromedical outcome of 16 U.S. Air Force aircrew members who returned to flight duty after stapedectomy between 1965 and 1992, Selected patients were subjected to centrifuge and altitude chamber testing before they returned to flight duty, No episodes of sudden hearing loss or vestibulopathic conditions have occurred in the entire study group, Guidelines for surgical technique, reconstruction materials, and postoperative aeromedical testing are proposed for evaluating selected stapedectomy patients before their return to flight status. C1 Pittsburgh Ear Associates, Otol Neurootol, Pittsburgh, PA 15212 USA. Wilford Hall USAF Med Ctr, Dept Otolaryngol Head & Neck Surg, Lackland AFB, TX 78236 USA. RP Arriaga, MA (reprint author), Pittsburgh Ear Associates, Otol Neurootol, 420 E North Ave,Suite 402, Pittsburgh, PA 15212 USA. NR 15 TC 6 Z9 6 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD JAN PY 1998 VL 118 IS 1 BP 9 EP 14 DI 10.1016/S0194-5998(98)70368-7 PG 6 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA YT003 UT WOS:000071554300003 PM 9450822 ER PT B AU Vanderburgh, DF AF Vanderburgh, DF BE Nelson, R Gelish, A Mun, SK TI PACS and teleradiology at the 3(rd) Medical Group, Elmendorf AFB, Alaska SO PACIFIC MEDICAL TECHNOLOGY SYMPOSIUM, PROCEEDINGS LA English DT Proceedings Paper CT Pacific Medical Technology Symposium (PACMEDTek) CY AUG 17-21, 1998 CL HONOLULU, HI SP Tripler Army Med Ctr AB After two years of extensive planning, the Department of Radiology at the 3(rd) MG (Medical Group, Elmendorf AFB, Anchorage, Alaska) established the first functional PACS in Alaska. Project Akamai provided the funding and planning expertise with (Department of Defense) DoD research dollars through a consortium of outstanding managers and consultants. Utilizing research money outside the 3(rd) MG budget had both disadvantages and advantages. The 3(rd) MG Radiology department faced marry political issues securing a final purchase order, similar to any hospital purchasing a multimillion-dollar system. The final purchase order, installation acceptance testing, training, and equipment integration (many systems including a GE PACS, Dejarnette gateways, Fuji CR, Access and Medweb servers, and Lumisys scanners) proceeded with great success. After one year of PACS, clinician acceptance is great because of increased radiology department service. The lessons learned are extremely vital as the 3(rd) MG moves into a new hospital with a newer and expanded PACS integrating with the Federal Health Care Partners at the VA hospital Bassett Army Medical Hospital (Fairbanks), Kodak (Coast Guard), and the new Alaska Native Medical Center. C1 3rd Med Grp, Elmendorf AFB, AK 99506 USA. RP Vanderburgh, DF (reprint author), 3rd Med Grp, 5800 Hosp Dr, Elmendorf AFB, AK 99506 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA BN 0-8186-8667-7 PY 1998 BP 125 EP 131 DI 10.1109/PACMED.1998.767944 PG 3 WC Computer Science, Interdisciplinary Applications; Medical Informatics SC Computer Science; Medical Informatics GA BN33G UT WOS:000081642800020 ER PT S AU Stright, JR Coffield, PC Brooks, GW AF Stright, JR Coffield, PC Brooks, GW BE Shi, HC Coffield, PC TI An analog VLSI implementation of a morphological associative memory SO PARALLEL AND DISTRIBUTED METHODS FOR IMAGE PROCESSING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Parallel and Distributed Methods for Image Processing II CY JUL 19-20, 1998 CL SAN DIEGO, CA SP SPIE DE morphological associative memory; morphological neural network AB The theory and application of morphological associative memories and morphological neural networks in general are emerging areas of research in computer science. The concept of a morphological associative memory differs from a more conventional associative memory by the nonlinear functionality of the synaptic connection. By taking the maximum of sums instead of the sum of products, morphological network computation is inherently nonlinear. Hence, the morphological associative memory does not require any ad hoc methodology to interject a nonlinear state. In this paper, we introduce a very large scale integration analog circuit design that describes the nonlinear functionality of the synaptic connection. We specifically describe the fundamental circuit needed to implement a basic additive maximum associative memory, and describe noise conditions under which this memory will perform flawlessly. As a potential application, we propose the use of the analog circuit to real-time operation on or near a focal plane array sensor. C1 USAF, Res Lab, MNGI, Eglin AFB, FL 32542 USA. RP Stright, JR (reprint author), USAF, Res Lab, MNGI, Eglin AFB, FL 32542 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 0-8194-2907-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3452 BP 14 EP 22 DI 10.1117/12.323470 PG 9 WC Computer Science, Software Engineering SC Computer Science GA BL80Z UT WOS:000076793800002 ER PT S AU Brown, W Chapman, SC Grande, M Hardy, DA Singer, HJ Anderson, RR Reeves, GD AF Brown, W Chapman, SC Grande, M Hardy, DA Singer, HJ Anderson, RR Reeves, GD BE Blake, JB Slavin, JA TI Case studies of ion energisation events near substorm onset SO PARTICLE ACCELERATION IN SPACE PLASMAS SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT D0 3 Symposium of COSPAR Scientific-Commission-D on Particle Acceleration in Space Plasmas at the 31st COSPAR Scientific Assembly CY JUL 14-21, 1996 CL UNIV BIRMINGHAM, BIRMINGHAM, ENGLAND SP Comm Space Res, Sci Comm Solar Terr Phys, European Space Agcy HO UNIV BIRMINGHAM ID CRRES AB In a recent one-dimensional self-consistent hybrid code simulation of the local dipolarisation of the initially distended magnetic field in the near-earth nightside region, (Richardson and Chapman, 1994), initially isotropic ions were accelerated up to twice the Alfven speed along the direction of the magnetic field. A bistreaming ion population was generated in the weak field region at the centre of the reversing held, and monostreaming ions were found to move away from the region of dipolarisation, Moreover, a bipolar signature in the cross tail component of the:field and fast magnetosonic waves propagating away from the reversal region are predicted by the simulation. We test these predictions by examining particle and magnetic field data from the Low Energy Plasma Analyser (LEPA) experiment and fluxgate magnetometer instrument onboard the Combined Release and Radiation Effects Satellite (CRRES), We examine a set of events that were found to be consistent with some of the features of the simulation results. (C) 1998 COSPAR. Published by Elsevier Science Ltd. C1 Univ Warwick, Space & Astrophys Grp, Coventry CV4 7AL, W Midlands, England. USAF, Phillips Lab, Bedford, MA 01731 USA. NOAA, RESE, Space Environm Lab, Boulder, CO 80303 USA. Univ Iowa, Iowa City, IA 52242 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. DRAL, Didcot, Oxon, England. RP Brown, W (reprint author), Univ Warwick, Space & Astrophys Grp, Coventry CV4 7AL, W Midlands, England. RI Chapman, Sandra/C-2216-2008; Reeves, Geoffrey/E-8101-2011; Grande, Manuel/C-2242-2013 OI Chapman, Sandra/0000-0003-0053-1584; Reeves, Geoffrey/0000-0002-7985-8098; Grande, Manuel/0000-0002-2233-2618 NR 5 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 0273-1177 BN 0-08-043312-X J9 ADV SPACE RES PY 1998 VL 21 IS 4 BP 641 EP 644 DI 10.1016/S0273-1177(97)00976-9 PG 4 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences; Physics, Fluids & Plasmas SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences; Physics GA BL12R UT WOS:000074378900019 ER PT S AU Hollkamp, JJ Gordon, RW AF Hollkamp, JJ Gordon, RW BE Davis, LP TI Experiments with particle damping SO PASSIVE DAMPING AND ISOLATION - SMART STRUCTURES AND MATERIALS 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Smart Structures and Materials 1998 - Passive Damping and Isolation CY MAR 02-03, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers, Soc Exptl Mech Inc, Amer Soc Mech Engineers, BF Goodrich Aerosp, USAF Res Lab, Def Adv Res Projects Agcy, Ceram Soc Japan, Intelligent Mat Forum, Japan, USA Res Off DE particle damping; impact damping; high cycle fatigue; gas turbine engines AB High cycle fatigue in jet engines is a current military concern. The vibratory stresses that cause fatigue can be reduced by adding damping. However, the high temperatures that occur in the gas turbine greatly hinder the application of mature damping technologies. One technology which may perform in the harsh environment is particle damping. Particle damping involves placing metallic or ceramic particles inside structural cavities. As the cavity vibrates, energy is dissipated through particle collisions. Performance is influenced by many parameters including the type, shape, and size of the particles; the amount of free volume for the particles to move in; density of the particles; and the level of vibration. This pager presents results from a series of experiments designed to gain an appreciation of the important parameters. The experimental setup consists of a cantilever beam with drilled holes. These holes are partially filled with particles. The types of particles, location of the particles, fill level, and other parameters are varied. Damping is estimated for each configuration. Trends in the results are studied to determine the influence of the varied parameter. C1 USAF, Res Lab, VASV, AFRL, Wright Patterson AFB, OH 45433 USA. RP Hollkamp, JJ (reprint author), USAF, Res Lab, VASV, AFRL, Wright Patterson AFB, OH 45433 USA. NR 0 TC 19 Z9 25 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 0-8194-2771-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3327 BP 2 EP 12 DI 10.1117/12.310675 PG 11 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics; Optics SC Acoustics; Engineering; Materials Science; Mechanics; Optics GA BL31L UT WOS:000075068000001 ER PT S AU Sciulli, D Inman, DJ AF Sciulli, D Inman, DJ BE Davis, LP TI Isolation design for systems with flexible base and equipment SO PASSIVE DAMPING AND ISOLATION - SMART STRUCTURES AND MATERIALS 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Smart Structures and Materials 1998 - Passive Damping and Isolation CY MAR 02-03, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers, Soc Exptl Mech Inc, Amer Soc Mech Engineers, BF Goodrich Aerosp, USAF Res Lab, Def Adv Res Projects Agcy, Ceram Soc Japan, Intelligent Mat Forum, Japan, USA Res Off DE vibration isolation; passive damping; active damping; isolator placement; flexible systems AB Current literature has not fully explored the choice of isolator mount frequency or isolator placement for flexible systems. It is commonly suggested that isolators should be designed with a low-mount frequency. It is shown that these isolators tend to perform best in an overall sense; however, mount frequencies designed between system modes tend to have a coupling effect. That is, the lower frequencies have such a strong interaction between each other that when isolator damping is present, multiple system modes are attenuated. Also, for low-mount frequency designs, the first natural frequency can shift as much as 15.6%. For a mid-mount frequency design, the shift of the first three modes can be as high as 34.9%, 26.6% and 11.3%, respectively. Also, when the base and system are flexible, isolator placement becomes a critical issue. There can be as much as 16% difference in the first mode for low-frequency mount design and as high as 25% for a mid-frequency mount design. C1 USAF, Res Lab, VSDV, Kirtland AFB, NM 87117 USA. RP Sciulli, D (reprint author), USAF, Res Lab, VSDV, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2771-3 J9 P SOC PHOTO-OPT INS PY 1998 VL 3327 BP 378 EP 386 DI 10.1117/12.310700 PG 9 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics; Optics SC Acoustics; Engineering; Materials Science; Mechanics; Optics GA BL31L UT WOS:000075068000033 ER PT S AU Smith, R Sundstrom, B Belcher, B Ewen, D AF Smith, R Sundstrom, B Belcher, B Ewen, D BE Smith, RM TI ROSCAM - A 95 GHz radiometric one second camera SO PASSIVE MILLIMETER-WAVE IMAGING TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Passive Millimeter-Wave Imaging Technology II CY APR 13, 1998 CL ORLANDO, FL SP SPIE C1 USAF, Res Lab, Armament Directorate, Adv Guidance Div, Eglin AFB, FL 32542 USA. RP Smith, R (reprint author), USAF, Res Lab, Armament Directorate, Adv Guidance Div, Eglin AFB, FL 32542 USA. NR 0 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 0-8194-2827-2 J9 P SOC PHOTO-OPT INS PY 1998 VL 3378 BP 2 EP 13 DI 10.1117/12.319389 PG 12 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL67W UT WOS:000076298300001 ER PT J AU Tankersley, MS Butler, WK AF Tankersley, MS Butler, WK TI Meperidine-induced local urticaria in a male adolescent with sickle cell disease SO PEDIATRIC ASTHMA ALLERGY & IMMUNOLOGY LA English DT Article ID CONSCIOUS SEDATION; FLARE REACTION; ENDOSCOPY AB Anaphylaxis is rare with opiates. A local cutaneous reaction may occur with the intravenous infusion of meperidine and should not be confused with a systemic reaction. We present a case of a local urticarial reaction associated with the intravenous infusion of meperidine in a patient with sickle cell disease. No systemic manifestations occurred and the reaction resolved with the administration of an antihistamine. Localized cutaneous reactions have been reported previously with the intravenous infusion of meperidine. Rarely, a large urticarial response may occur at the infusion site resulting from direct mast cell release by the drug, A large, localized urticarial reaction may be seen with the infusion of meperidine and the patient should not be labeled as having a hypersensitivity to the drug in the absence of systemic signs or symptoms. C1 Wilford Hall USAF Med Ctr, Dept Allergy & Immunol, Lackland AFB, TX 78236 USA. RP Tankersley, MS (reprint author), Wilford Hall USAF Med Ctr, Dept Allergy & Immunol, 2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0883-1874 J9 PEDIATR ASTHMA ALLER JI Pediatr. Asthma Allergy Immunol. PY 1998 VL 12 IS 1 BP 49 EP 51 DI 10.1089/pai.1998.12.49 PG 3 WC Allergy; Immunology; Pediatrics; Respiratory System SC Allergy; Immunology; Pediatrics; Respiratory System GA ZY397 UT WOS:000074617200007 ER PT J AU Beer, JMA Ghani, N Previc, FH Campbell, JM AF Beer, J. M. A. Ghani, N. Previc, F. H. Campbell, J. M. TI Speed can influence aim-point judgments even before illusory depth cues enter the picture SO PERCEPTION LA English DT Meeting Abstract C1 [Beer, J. M. A.; Ghani, N.; Campbell, J. M.] Veridian Inc, Brooks AFB, TX 78235 USA. [Previc, F. H.] USAF, Res Lab HEPM, Brooks AFB, TX 78235 USA. EM jbeer@alcft.brooks.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON NW2 5JN, ENGLAND SN 0301-0066 J9 PERCEPTION JI Perception PY 1998 VL 27 SU S BP 58 EP 59 PG 2 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA V17AP UT WOS:000207910400157 ER PT J AU Pierce, BJ Howard, IP Feresin, C AF Pierce, BJ Howard, IP Feresin, C TI Depth interactions between inclined and slanted surfaces in vertical and horizontal orientations SO PERCEPTION LA English DT Article ID STEREO DEPTH; PERCEPTION; MOTION; ANISOTROPIES; DISPARITIES; BRIGHTNESS; HOROPTER; CONTRAST; ANALOGY AB Depth interactions between a frontal test surface and an adjacent induction surface were measured as a function of the type of disparity in the induction surface and of the vertical/horizontal orientation of the boundary between the surfaces. The types of disparity were 4 degrees horizontal-shear disparity, 4 degrees vertical-shear disparity, and 4 degrees rotation disparity; 4% horizontal-size disparity, 4% vertical-size disparity, and 4% overall-size disparity. Depth contrast in a frontal surface was produced by surfaces containing horizontal-size disparity but not by those containing horizontal-shear disparity. Vertical-shear and vertical-size disparities produced induced effects in both the induction and the test surface, which is here explained in terms of deformation-disparity processing. Effects of rotation disparity on the test surface can be accounted for in terms of cyclovergence, deformation disparity, and perhaps also depth contrast. The fact that horizontal-size disparity produced more depth contrast than horizontal-shear disparity is due to an anisotropy of disparity processing rather than the relative orientation of the surfaces. Ground surfaces appeared more slanted than ceiling surfaces. Surfaces containing horizontal disparities produced a sharp boundary with the test surface because horizontal disparities are processed locally. Surfaces with vertical disparities produced a gradual boundary with the test surface because vertical disparities are processed over a wider area. C1 USAF, Res Lab, Mesa, AZ 85206 USA. York Univ, Ctr Vis Res, N York, ON M3J 1P3, Canada. Univ Trieste, Dept Psychol, I-34123 Trieste, Italy. RP Pierce, BJ (reprint author), USAF, Res Lab, 6001 S Power Rd,Bldg 558, Mesa, AZ 85206 USA. EM pierce@alhra.af.mil; ihoward@hpl.ists.ca OI Feresin, Catina/0000-0003-1563-7445 NR 35 TC 17 Z9 17 U1 0 U2 1 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON NW2 5JN, ENGLAND SN 0301-0066 J9 PERCEPTION JI Perception PY 1998 VL 27 IS 1 BP 87 EP 103 DI 10.1068/p270087 PG 17 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA ZF920 UT WOS:000072946500008 PM 9692090 ER PT J AU Howard, IP Pierce, BJ AF Howard, IP Pierce, BJ TI Types of shear disparity and the perception of surface inclination SO PERCEPTION LA English DT Article ID CONTRAST; DEPTH; CYCLOVERGENCE; STEREOPSIS; STIMULUS; VISION; SLANT; MODEL AB A study is reported of (i) the perceived inclination of a textured surface in depth about a horizontal axis as a function of disparity magnitude for horizontal-shear disparity, vertical-shear disparity, and rotation disparity; and (ii) interactions between patterns with shear or rotation disparity and superimposed or adjacent patterns or lines with zero disparity. Horizontal-shear disparity produced strong inclination which was enhanced by superimposed or adjacent zero-disparity stimuli. It produced little or no inclination contrast in superimposed or adjacent zero-disparity stimuli. Vertical-shear disparity produced inclination in the opposite direction (induced effect) which was reduced to near zero by a superimposed zero-disparity pattern. Adjacent vertical-shear and zero-disparity patterns appeared inclined at slightly different angles with a wide curved boundary. This suggests that vertical-shear disparities are averaged over a wide area. Rotation disparity produced minimal inclination. A superimposed or adjacent zero-disparity line appeared strongly inclined. A superimposed or adjacent zero-disparity pattern appeared vertical and caused the pattern with rotation disparity to appear inclined. Four mechanisms are proposed to account for the results: depth contrast, depth enhancement, deformation-disparity processing, and disparity transfer arising from cyclovergence. C1 York Univ, Ctr Vis Res, N York, ON M3J 1P3, Canada. USAF, Res Lab, Mesa, AZ 85206 USA. RP Howard, IP (reprint author), York Univ, Ctr Vis Res, 103 Farquharson Bldg, N York, ON M3J 1P3, Canada. NR 23 TC 4 Z9 4 U1 0 U2 1 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON NW2 5JN, ENGLAND SN 0301-0066 J9 PERCEPTION JI Perception PY 1998 VL 27 IS 2 BP 129 EP 145 DI 10.1068/p270129 PG 17 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA ZQ131 UT WOS:000073825400002 PM 9709447 ER PT J AU Geri, GA Pierce, BJ AF Geri, G. A. Pierce, B. J. TI Eccentricity scaling of perceived velocity at a constant viewing distance SO PERCEPTION LA English DT Meeting Abstract C1 [Geri, G. A.] Raytheon Syst Co, Visual Res Lab, Mesa, AZ 85206 USA. [Pierce, B. J.] HEA, AF Res Lab, Mesa, AZ 85206 USA. EM george.geri@williams.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU PION LTD PI LONDON PA 207 BRONDESBURY PARK, LONDON NW2 5JN, ENGLAND SN 0301-0066 J9 PERCEPTION JI Perception PY 1998 VL 27 SU S BP 189 EP 189 PG 1 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA V17AP UT WOS:000207910400510 ER PT J AU Rao, S Hernandez, C Simmons, JP Parthasarathy, TA Woodward, C AF Rao, S Hernandez, C Simmons, JP Parthasarathy, TA Woodward, C TI Green's function boundary conditions in two-dimensional and three-dimensional atomistic simulations of dislocations SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID CORE STRUCTURE; TRANSITION-METALS; PEIERLS STRESS; LATTICE; BODY; INTERMETALLICS; PROPAGATION; MOBILITY; STATICS; KINKS AB A method for dynamically updating the boundary conditions of atomistic simulations is presented. The lattice Green's function boundary relaxation method, originally introduced by Sinclair et al. in 1978, is extended to treat three-dimensional (3D) simulations. The boundary conditions for two-dimensional (2D) and 3D defect cells are evaluated using line and point force distributions respectively. The method is general and has been incorporated into several potential interaction schemes. Examples of the method using embedded-atom method potentials are presented for the following: simulation of a straight (a/2)[110] screw dislocation in Ni; an isolated a(001) kink on an (a/2)[111] screw dislocation in bcc Fe; simulation of a periodic array of a(001) kinks on an (a/2)[111] screw dislocation in bcc Fe. The first simulation is 2D in nature and the last two defects are 3D. C1 USAF, Wright Lab, MLLM, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. SW Ohio Council Higher Educ, Dayton, OH 45420 USA. RP Rao, S (reprint author), USAF, Wright Lab, MLLM, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 42 TC 92 Z9 92 U1 1 U2 18 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD JAN PY 1998 VL 77 IS 1 BP 231 EP 256 PG 26 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA YT346 UT WOS:000071592400014 ER PT S AU Smith, G Estes, MJ Dang, T Salvador, AA Fan, Z Xu, G Botchkarev, A Morkoc, H Wolf, P AF Smith, G Estes, MJ Dang, T Salvador, AA Fan, Z Xu, G Botchkarev, A Morkoc, H Wolf, P BE Brown, GJ TI Megahertz bandwidth AlxGa1-xN/GaN-based pin detectors SO PHOTODETECTORS: MATERIALS AND DEVICES III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Photodetectors - Materials and Devices III CY JAN 28-30, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE ultraviolet detectors; gallium nitride; aluminum gallium nitride; p-i-n detectors AB This paper discusses recent results of time response and spectral responsivity measurements made on AlxGa1-xN/GaN-based p-i-n ultraviolet (UV) detectors with .03 T-1) excitation energies obtained at the B3LYP level are in better agreement with experiment. Except for the fluoro group, all beta-halogen auxochromes red-shift the UV and visible bands of the free-base and zinc porphyrin chromophores. C1 USAF, Mat & Mfg Directorate, MLPJ, AFRL, Wright Patterson AFB, OH 45433 USA. RP Nguyen, KA (reprint author), USAF, Mat & Mfg Directorate, MLPJ, AFRL, Wright Patterson AFB, OH 45433 USA. NR 44 TC 0 Z9 0 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA BN 1-56555-145-1 PY 1998 BP 63 EP 68 PG 6 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Multidisciplinary SC Computer Science; Engineering GA BM99U UT WOS:000080386700011 ER PT S AU Reising, JM Liggett, KK Kustra, TW Snow, MP Hartsock, DC Barry, TP AF Reising, JM Liggett, KK Kustra, TW Snow, MP Hartsock, DC Barry, TP GP HFES HFES HFES TI Evaluation of pathway symbology used to land from curved approaches with varying visibility conditions SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB Global Positioning System technology has the potential to revolutionize both commercial and military aircraft landing procedures. It will enable pilots to fly complex, curved approaches rather than the more simple straight-in approaches necessitated by the Instrument Landing System used at most large airports. To complement this technology, Head-Up Display pathway symbology was developed for use in the aircraft to help pilots stay on course during these complex landings. Thirteen Air Force pilots used this pathway symbology in a simulator to land under Visual Meteorological, Partial Instrument Meteorological and Full Instrument Meteorological visibility conditions. Deviations from commanded flight path, as well as lateral and longitudinal deviations from a desired runway touchdown point, were measured. Results indicated that landing performance was acceptable for all pilots and functionally equivalent in all weather conditions. Results bf this study suggest that pathway symbology could provide the cues necessary to successfully fly complex, curved approaches to landing. In addition, the merits of using Equivalency analysis, rather than traditional analysis of Variance in testing for performance differences is discussed. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1 EP 5 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900001 ER PT S AU Nelson, WT Bolia, RS McKinley, RL Chelette, TL Tripp, LD Esken, RL AF Nelson, WT Bolia, RS McKinley, RL Chelette, TL Tripp, LD Esken, RL GP HFES HFES HFES TI Localization of virtual auditory cues in a high +G(z) environment SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID DISPLAYS AB The ability to localize a virtual auditory source was evaluated under varying levels of sustained (+G(z)) acceleration. Participants were required to judge the locations of virtual auditory cues located along the horizontal plane (elevation 0 degrees) during exposure to 1.0, 1.6, 2.5, 4.0, 5.6, and 7.0 +G(z). The experiment was conducted at the Air Force Research Laboratory's Dynamic Environment Simulator-a man-rated, three-axis centrifuge. No significant increases in localization error were found between 1.0 and 5.6 +G(z); however, a significant increase did occur at the 7.0 +G(z) level. In addition, the percentage of reversals did not vary as a function of +G(z) level. Collectively, these results indicate that one's ability to localize virtual auditory cues is well maintained at various levels of sustained acceleration. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Nelson, WT (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 20 TC 1 Z9 1 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 97 EP 101 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900020 ER PT S AU Tirre, WC AF Tirre, WC GP HFES HFES HFES TI Crew selection for uninhabited air vehicles: Preliminary investigation of the air vehicle operator (AVO) SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID INDIVIDUAL-DIFFERENCES; ABILITIES AB Because of the similarity of the AVO console to a desktop flight simulator, a preliminary idea of what aptitude factors would predict success in AVO training might be obtained through a validation study using a desktop flight simulator as the criterion task. In this study, 171 young men and women learned to fly a simulated light aircraft. The participants also took a comprehensive 8-hour battery of computer-based tests. Results indicated that learning was predicted well by general cognitive ability (g)/ working memory (WM) and multilimb coordination. When structural equation modeling was used to distinguish declarative and procedural learning, declarative learning was found to be strongly dependent on g/WM, which is consistent with previous research. That g/WM did not correlate with procedural learning explains why correlations of this ability with learning diminished as instruction moved from a declarative to procedural emphasis. Only multilimb coordination ability was strongly related to procedural learning. C1 USAF, Res Lab, Human Effectiveness Directorate, Brooks AFB, TX 78235 USA. RP Tirre, WC (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Brooks AFB, TX 78235 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 118 EP 122 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900024 ER PT S AU Martin, E Lyon, DR Schreiber, BT AF Martin, E Lyon, DR Schreiber, BT GP HFES HFES HFES TI Designing synthetic tasks for human factors research: An application to uninhabited air vehicles SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB Research from different laboratories could be compared more easily if a common set of research tasks were used. Such tasks should be amenable to controlled laboratory research, yet the results should generalize to important real-world tasks. In this paper, we describe the design of synthetic tasks, which are research tasks constructed by systematic abstraction from a corresponding real-world task. We present as an example a laboratory task (the cloud-break task) derived from a particularly demanding part of the reconnaissance mission of the USAF Predator uninhabited air vehicle. We describe potential pitfalls in decoupling a synthetic task from its normal mission context, and discuss some lessons learned from a preliminary design study. C1 USAF, Washington, DC 20330 USA. RP Martin, E (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 8 Z9 8 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 123 EP 127 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900025 ER PT S AU Hurwitz, JB AF Hurwitz, JB GP HFES HFES HFES TI Modeling the effects of sleep deprivation on real-time risky decision-making SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID INDIVIDUAL-DIFFERENCES; VIGILANCE; TASK AB Increased real-time risk-taking under sleep loss could be marked by changes in risk perception or acceptance. Risk-perception processes are those involved in estimating real-time parameters such as the speeds and distances of hazardous objects. Risk-acceptance processes relate to response choices given risk estimates. Risk-taking under fatigue was studied using a simulated intersection-crossing driving task in which subjects decided when it was safe to cross an intersection as an oncoming car approached from the cross street. The subjects performed this task at 3-hour intervals over a 36-hour period without sleep. Results were modeled using a model of real-time risky decision making that has perceptual components that process speed, time and distance information, and a decisional component for accepting risk. Results showed that varying a parameter for the decisional component across sessions best accounted for variations in performance relating to time of day. C1 USAF, Res Lab, HEJC, Brooks AFB, TX 78235 USA. RP Hurwitz, JB (reprint author), USAF, Res Lab, HEJC, Brooks AFB, TX 78235 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 330 EP 334 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900068 ER PT S AU McNeese, MD AF McNeese, MD GP HFES HFES HFES TI New frontiers in cognitive task analysis: Bridging the gap between cognitive analysis and cognitive engineering SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP McNeese, MD (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 377 EP 379 PG 3 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900078 ER PT S AU Hickox, JC Turner, SL Aretz, AJ AF Hickox, JC Turner, SL Aretz, AJ GP HFES HFES HFES TI Enhancing learning of Human Factors with web-based technology applications SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB This paper describes a case study of two senior-level undergraduate courses in the Human Factors Engineering curriculum at the United States Air Force Academy. These courses were modified extensively to employ World Wide Web (WWW) and internet technologies as an assist to standard pedagogies. The modifications were made in response to multiple institutional goals and student needs. Descriptive survey data were collected to gauge student receptivity to these changes. Results suggest initial resistance, followed by a bimodal response of either strongly embracing the technology, or mildly rejecting it. Additional survey results are discussed along with instructor impressions of effectiveness. C1 USAF Acad, Dept Behav Sci & Leadership, Colorado Springs, CO 80840 USA. RP Hickox, JC (reprint author), USAF Acad, Dept Behav Sci & Leadership, Colorado Springs, CO 80840 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 602 EP 605 PG 4 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900126 ER PT S AU Gibb, RW Caldwell, BSC Garland, DJ Goldberg, JH Hickox, JC Payne, DG Wogalter, MS AF Gibb, RW Caldwell, BSC Garland, DJ Goldberg, JH Hickox, JC Payne, DG Wogalter, MS GP HFES HFES HFES TI Undergraduate human factors curriculum and introductory Human Factors course content SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB This panel provided a discussion format for six academic institutions to share their Human Factors (HF) curriculum and more specifically, to educate others on how they teach their introductory HF course. Each panelist addressed the following topics regarding their HF curriculum: foundation courses of the department's degree and specific HF courses offered. Then the panelists focused their discussions to their specific introductory HF course: philosophy; text book(s) used; course objectives; course syllabus flow; grading practices; and specific lesson exercises/labs. C1 USAF Acad, Dept Behav Sci & Leadership, Colorado Springs, CO 80840 USA. RP Gibb, RW (reprint author), USAF Acad, Dept Behav Sci & Leadership, Colorado Springs, CO 80840 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 619 EP 623 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900130 ER PT S AU Robinette, KM AF Robinette, KM GP HFES HFES HFES TI Multivariate methods in engineering anthropometry SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB Engineers and scientists have known for at least 45 years that univariate descriptive statistics, particularly percentiles, are inappropriate for use in designs that involve more than one dimension. Yet, the non-existent 5th percentile woman, and 95th percentile man are commonly referred to in the literature today. Arguments against using percentiles are numerous and compelling. It has been demonstrated that: 1) they will not ensure the accommodation of the desired population, 2) they are not additive so they will result in strangely proportioned models, and 3) they result in designs that waste materials. The source of the problem is the fact that they are univariate tone-dimensional) statistics applied to multivariate (many dimensional) situations. The primary argument for using percentiles has been that there were no alternatives. In this symposium we seek to remedy that. The speakers in this symposium will describe, compare, contrast and demonstrate some of the multivariate alternatives they have been developing and using. It is hoped that this will lead the way for other engineers and scientists in the field. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Robinette, KM (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 6 TC 3 Z9 3 U1 0 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 719 EP 721 PG 3 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900152 ER PT S AU Pierce, BJ Geri, GA AF Pierce, BJ Geri, GA GP HFES HFES HFES TI The implications of image collimation for flight simulator training SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB There is some question as to whether non-collimated (i.e., real) imagery viewed at one meter or less provides sufficiently realistic visual cues to support out-the-window flight simulator training. As a first step toward answering this question, we have obtained perceived size, and velocity estimates using both simple stimuli in a controlled laboratory setting and full simulator imagery in an apparatus consisting of optically combined collimated and real-image displays. In the size study it was found that real imagery appeared 15-30% smaller than collimated imagery. In the velocity studies, the laboratory data showed that the perceived velocity of real imagery was: less than that of collimated imagery. No perceived velocity effects were found with the simulator imagery. Results support the position that for training tasks requiring accurate perception of spatial and temporal aspects of the simulated visual environment, misperceptions of size, but not velocity, need to be considered when real-image displays are used. C1 USAF, Res Lab, Mesa, AZ 85206 USA. RP Pierce, BJ (reprint author), USAF, Res Lab, 6001 S Power Rd,Bldg 558, Mesa, AZ 85206 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1383 EP 1387 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900288 ER PT S AU Wetzel, PA Anderson, GM Barelka, BA AF Wetzel, PA Anderson, GM Barelka, BA GP HFES HFES HFES TI Instructor use of eye position based feedback for pilot training SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB We conducted an 18 month study on the implementation and evaluation of a portable eye tracking system in a training environment. The system was used by F-16 simulator instructors to provide instructional feedback to F-16 student pilots during flight simulator training missions. The head-mounted components of the eye tracking system consist of a two-dimensional eye position measurement system and a miniature video scene camera. When displayed on a video monitor, a cursor corresponding to the student's line of sight allows the instructor to follow the student's visual scan pattern. The portable system can be used in a number of environments and applications to objectively assess visual behavior, to develop effective visual behavior, and to enhance training. In addition, the companion, real-time, automated analysis system can analyze, quantify, and summarize scan path behavior from recorded videotape. C1 USAF, Res Lab, Raytheon Training Serv Inc, Mesa, AZ USA. RP Wetzel, PA (reprint author), USAF, Res Lab, Raytheon Training Serv Inc, Mesa, AZ USA. NR 4 TC 4 Z9 4 U1 1 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1388 EP 1392 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900289 ER PT S AU Goettl, BP Anthony, M Derek, K Snooks, S Shebilske, WL AF Goettl, BP Anthony, M Derek, K Snooks, S Shebilske, WL GP HFES HFES HFES TI Emphasis, gender and interaction anxiety in individual and dyadic training protocols SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID COMPLEX SKILLS; GAME AB Improvements in computer processing capacity make computer-based training systems a more effective and viable option. Yet in the face of perennially diminishing military budgets, creative solutions must be found to reduce costs of such systems. With these two goals in mind, we explored the factorial combination of a dyadic protocol manipulation (individuals versus dyad) and emphasis change manipulation (total score versus component scores) for training a complex task (Space Fortress). In addition, we examined the potential interactions these treatments may have with learner variables such as gender and interaction anxiety. The results suggested that dyads improved more than individuals on ship control. Gender interacted with emphasis indicating that women, but not men, benefited from emphasis change. In addition, individuals high in interaction anxiety were adversely effected by the dyadic protocols especially when combined with variable emphasis on components. The results suggest that dyadic training may be an effective way to increase training resource efficiency while producing modest benefits in training effectiveness and that emphasis change can improve the training effectiveness. However, both effects may be limited by individual differences. C1 Armstrong Lab, Brooks AFB, TX 78235 USA. RP Goettl, BP (reprint author), Armstrong Lab, Brooks AFB, TX 78235 USA. NR 9 TC 0 Z9 0 U1 1 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1412 EP 1416 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900295 ER PT S AU Draper, MH AF Draper, MH GP HFES HFES HFES TI The effects of image scale factor on vestibulo-ocular reflex adaptation and simulator sickness in head-coupled virtual environments SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID HUMANS AB An experiment was conducted to determine the effects of virtual image scale factor on vestibule-ocular reflex (VOR) adaptation and simulator sickness as a result of exposure to a head-coupled virtual interface. Subjects were exposed for 30 minutes, completing visual search tasks using active, unrestricted yaw head movement rotations. Three levels of image scale-factor changes (0.5X, 1.0X, 2.0X magnification) were explored. It was hypothesized that scale factors deviating from 1.OX magnification would cause VOR gain adaptation and increased simulator sickness. A secondary hypothesis predicted a moderate correlation between VOR gain adaptation and simulator sickness. Results demonstrated that significant VOR adaptation occurred only in the 0.5X and 2.0X scale conditions. VOR gain decreased an average of 15% in the 0.5X condition and increased an average of 6% in the 2.0X condition. Simulator sickness magnitudes in these two conditions were over twice that of the 1.OX condition. Only weak correlations were found between VOR gain adaptation and simulator sickness. Virtual interface design guidelines are suggested to minimize unwanted interface-generated effects on the user. C1 USAF, Wright Patterson AFB, OH 45433 USA. RP Draper, MH (reprint author), USAF, Wright Patterson AFB, OH 45433 USA. NR 11 TC 4 Z9 4 U1 0 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1481 EP 1485 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900309 ER PT S AU Eggleston, RG Janson, WP Aldrich, KA AF Eggleston, RG Janson, WP Aldrich, KA GP HFES HFES HFES TI A comparison of direct and indirect input devices in a volumetric interactive virtual environment workspace SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB The purpose of this study was to evaluate the impact of two different types of input devices on psychomotor performance in a "full" 3D (volumetric) virtual environment. Three subjects used both a direct input device (hand-held stylus) and an indirect input device (6 degree of freedom, fixed mounted force device) to accomplish aimed movement to a target located in one of eight depth planes. Directness was characterized in terms of action space and perception space coincidence and natural kinematic arm-hand movements. Different instructions were used to place different demands on coordination of movement. Aim point performance was evaluated in terms of aiming speed and accuracy, and steadiness at the terminal point. A descriptive analysis showed consistently better performance on all measures with the direct device. A statistical analysis confirmed these trends, although significance often was not always achieved due to limited experimental power. In general, the results suggest an advantage for the direct input device in the range of 30% to 73% across target locations, depending on type of performance measured. The data are discussed in terms of action and perception space coincidence and the coordination of the multiple degrees of freedom property of external input devices. C1 USAF, Res Lab, Human Effectiveness Directorate, Crew Syst Div, Wright Patterson AFB, OH 45433 USA. RP Eggleston, RG (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Crew Syst Div, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1516 EP 1520 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900316 ER PT S AU Eggleston, RG Janson, WP Aldrich, KA AF Eggleston, RG Janson, WP Aldrich, KA GP HFES HFES HFES TI Performance errors in virtual work: Separating display and input device effects of a virtual environment interface system SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc AB Psychomotor performance involves a closed-loop interaction of motor control and perception. A 3D virtual environment (VE) system inserts technology in both the motor side (input device) and perceptual side (viewing system) that will, affect task performance. Often performance studies associated with VE systems will compare input devices or viewing systems without considering the affect of other components on performance. This may create a problem in the attribution of the absolute magnitude of effect that can be assigned to a single subsystem/device in a VE system. This paper presents a data analysis strategy and procedure to address the attribution problem. The procedure is described and illustrated with data from a comparative device study involving a 3D virtual environment system. Benefits and limitations of the strategy are discussed. C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Eggleston, RG (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1521 EP 1525 PG 5 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900317 ER PT S AU Brungart, DS AF Brungart, DS GP HFES HFES HFES TI Three-dimensional auditory localization of nearby sources SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 42ND ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 42nd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY OCT 05-09, 1998 CL CHICAGO, IL SP Human Factors & Ergon Soc ID SOUND LOCALIZATION; HUMAN LISTENERS AB Although the head-related transfer function (HRTF) is known to change substantially with distance when a source is located within 1 m of the listener's head, very little is known about auditory localization performance in this region. In this experiment, an acoustic point source was used to measure auditory localization accuracy in azimuth, elevation and distance. The overall directional error (16.5 degrees) was similar to that measured in previous localization experiments with more distant sources, although the number of front-back reversals increased when the source was near the head. Distance localization was relatively accurate for lateral sources (stimulus-response correlation r>0.80) and relatively inaccurate for sources near the median plane, indicating that binaural difference cues are important to auditory distance perception for nearby sources. These results suggest that distance-dependent HRTFs measured for nearby sources could be used to provide robust binaural distance information in a virtual audio display. C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Brungart, DS (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. NR 12 TC 0 Z9 0 U1 0 U2 1 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-11-1 J9 HUM FAC ERG SOC P PY 1998 BP 1531 EP 1534 PG 4 WC Engineering, Aerospace; Computer Science, Cybernetics; Engineering, Multidisciplinary; Engineering, Industrial SC Engineering; Computer Science GA BM69U UT WOS:000079494900319 ER PT S AU Artelii, M Kramer, S AF Artelii, M Kramer, S GP IEEE TI A decision aid for selecting among alternative research and development investments SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB In periods of declining budgets, it becomes increasingly important to select the best possible research and development programs to invest in, and then to be able to articulate the rationale for the selection. Competing alternative investments will have a complex tradeoff of costs and diverse benefits, over different time periods and with different levels of certainty. In particular, the Air Force Research Laboratory needs to select which investments to pursue to improve fixed-wing vehicle performance. Multiobjective decision analysis is applied to this problem to produce a decision aid that captures their corporate objectives and allows full analysis of the tradeoffs between alternatives. The decision aid is described in detail and a brief example of its use is presented. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Artelii, M (reprint author), USAF, Inst Technol, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 60 EP 65 DI 10.1109/NAECON.1998.710097 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800005 ER PT S AU Overfield, B Thomas, J Cohen, M Sylvester, V Rogers, R Morgan, D AF Overfield, B Thomas, J Cohen, M Sylvester, V Rogers, R Morgan, D GP IEEE TI Air Target Algorithm Development (ATAD) SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB The Combat Air Forces have invested heavily in a sensor and weapon capability to detect and attack air targets at long ranges. Unfortunately, the ability to identify these targets lags behind these capabilities. Under the Air Force sponsored Air Target Algorithm Development (ATAD) program, model-based reasoning (MBR) fusion algorithms have been developed and demonstrated for improved air target identification (ID). The expected payoff is a robust ID algorithm that offers improved timelines, increased ID confidence enhanced target aspect performance, robustness to countermeasures, and longer ID ranges. The technology is applicable to all current and future fighter aircraft. C1 AFRL, SNAA, Wright Patterson AFB, OH 45433 USA. RP Overfield, B (reprint author), AFRL, SNAA, 2241 Avionics Circle, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 104 EP 110 DI 10.1109/NAECON.1998.710104 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800012 ER PT S AU Mitchell, RA Westerkamp, JJ AF Mitchell, RA Westerkamp, JJ GP IEEE TI Statistical feature based target recognition SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc 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 StaF classifier was initially developed far air target identification [3, 5-7] with the primary goal of increasing classifier robustness by maintaining high performance known target identification while minimizing errors from unknown targets. Meeting this requirement is significantly more challenging than forced decision classification. Results are presented showing the performance varability of the StaF classifier with respect to feature extraction variations. More importantly, the StaF classifier performance is compared to that of the quadratic classifier. It is found that the StaF classifier performs significantly better than the quadratic at high declaration rates demonstrating that the StaF classifier can significantly reduce errors associated with unknown targets while maintaining a high probability of correct classification. C1 AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. RP Mitchell, RA (reprint author), AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 111 EP 118 DI 10.1109/NAECON.1998.710105 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800013 ER PT S AU Fossa, CE Raines, RA Gunsch, GH Temple, MA AF Fossa, CE Raines, RA Gunsch, GH Temple, MA GP IEEE TI An overview of the IRIDIUM (R) low earth orbit (LEO) satellite system SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB This paper provides a tutorial overview of the IRIDIUM(R) low earth orbit (LEO) satellite system. Section I contains an introduction to the IRIDIUM(R) network as well as the system specifications. Section II discusses the satellite constellation design, orbital parameters, and horizontal pointing angles between satellites. Section III introduces the idea of time dependent connectivity in a mobile network, and analyzes the cycle of network connectivity for IRIDIUM(R). Section IV discusses the IRIDTUM(R) Time Division Multiple Access (TDMA) and Frequency Division Multiple Access (FDMA) schemes and uses these to calculate the overall system capacity. Section V examines the call processing procedure to include user location and call set up. Finally, Section VI analyzes the network performance in terms of end-to-end delay and hop count. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Fossa, CE (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 0 TC 19 Z9 21 U1 1 U2 4 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 152 EP 159 DI 10.1109/NAECON.1998.710110 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800018 ER PT S AU Luke, J Bittorie, JW Cannon, WJ Haldeman, DG AF Luke, J Bittorie, JW Cannon, WJ Haldeman, DG GP IEEE TI A commercial off-the-shelf based replacement strategy for aging avionics computers SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc 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 on 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 "bIackbox" level using existing qualification tests. C1 USAF, Res Lab, Washington, DC 20330 USA. RP Luke, J (reprint author), USAF, Res Lab, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 177 EP 181 DI 10.1109/NAECON.1998.710113 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800021 ER PT S AU Reinhart, T Boettcher, C Wasserman, H AF Reinhart, T Boettcher, C Wasserman, H GP IEEE TI An automated testing methodology based on self-checking software SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB New techniques are required to speed the software testing process and to enhance the ultimate reliability of mission-critical embedded information systems. Here we employ result-checking, a technique in which software assures the correctness of its own computations through efficient run-time checks. Building on previous work at U.C. Berkeley and Raytheon Systems Company, the Air Force Research Laboratory is funding the Automated Generation of Avionics Software Tests (AGAST) program to demonstrate that result-checking can be the basis for a flexible new methodology of software testing. This methodology aims at the production of software which has an enhanced sensitivity to its own errors (complemented with appropriate instrumentation), and which therefore may be tested with extremely high efficiency and accuracy. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Reinhart, T (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 205 EP 212 DI 10.1109/NAECON.1998.710118 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800026 ER PT S AU Pham, DT AF Pham, DT GP IEEE TI Applications of unsupervised clustering algorithms to aircraft identification using high range resolution radar SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc DE automatic target recognition (ATR); non-cooperative target recognition (NCTI); combat identification; high range resolution (HRR) radar; clustering; k-means; Kohonen; and pattern recognition AB Identification of aircraft from high range resolution (HRR) radar range profiles requires a database of information capturing the variability of the individual range profiles as a function of viewing aspect. This database can be a collection of individual signatures or a collection of average signatures distributed over the region of viewing aspect of interest. An efficient database is one which captures the intrinsic variability of the HRR signatures without either excessive redundancy (over-characterization) typical of single-signature databases or without the loss of information (under-characterization) common when averaging, arbitrary groups of signatures. The identification of "natural" clustering of similar HRR signatures provides a means for creating efficient databases of either individual signatures or of signature templates. Using a k-means and the Kohonen self-organizing feature net, we identify the natural clustering of the HRR radar range profiles into groups of similar signatures based on the match quality metric (Euclidean distance) used within a Vector Quantizer (VQ) classification algorithm. This greatly reduces the redundancy in such databases while retaining classification performance. Such clusters can be useful in template-based algorithms where groups of signatures are averaged to produce a template. Instead of basing the group of signatures to be averaged on arbitrary regions of viewing aspect, the averages are taken over the signatures contained in the natural clusters which have been identified. The benefits of applying natural cluster identification to individual-signature HRR data preparation are decreased algorithm memory and computational requirements with a consequent decrease in the time required to perform identification calculations. When applied to template databases the benefits are improved identification performance. This paper describes the techniques used for identifying HRR signature clusters and describes the statistical properties of such clusters. C1 USAF, Res Lab, AFRL SNZ, Wright Patterson AFB, OH 45433 USA. RP Pham, DT (reprint author), USAF, Res Lab, AFRL SNZ, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 228 EP 235 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800029 ER PT S AU Hallman, LB AF Hallman, LB GP IEEE TI Problems in the production of microelectronic equipment SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc C1 USAF, Div Aeronaut Syst, Wright Patterson AFB, OH 45433 USA. RP Hallman, LB (reprint author), USAF, Div Aeronaut Syst, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 237 EP 241 DI 10.1109/NAECON.1998.710122 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800030 ER PT S AU Haren, R AF Haren, R GP IEEE TI A method of determining accurate range capability for multispectral infrared sensors using simple modeling techniques SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB The Multispectral Air-to-Air Inhouse Feasibility Study has been chartered to adapt the lessons learned from the Brassboard Airborne Multispectral Sensor System Specification (BAMS) program (contract # F33615-93-C-1267) from the air-to-ground scenario to the air-to-air search and track scenario. This is an interim report in an investigation of the feasibility of ah-to-ah multispectral techniques that will generate the basis fora planned follow-on effort The BAMS effort is developing the capability to detect ground targets in deep-hide and under camouflage by exploiting the spectral characteristics of the target [I]. These same benefits should be adaptable for aerial search. This method of detection is more immune to low contrast or high clutter than a broadband sensor, and allows the use of larger pixels which translates into a much larger search volume. The downside is that the smaller wavebands inherent to multispectral sensors results in a smaller number of collected photons limiting the overall range capability. However, it is expected that multispectral sensors will have a distinct advantage over broadband sensors in the look-down scenario where the background is highly cluttered and the target is low contrast This scenario will be used for a direct comparison between the two sensor approaches. The methodology for determining the detection range capabilities for broadband and multispectral sensors is presented in this paper along with a summary of the approach for determining the expected performance of multispectral aerial search sensors. C1 USAF, Res Lab, AFRL, SNJT, Wright Patterson AFB, OH 45433 USA. RP Haren, R (reprint author), USAF, Res Lab, AFRL, SNJT, 3109 P St,Bldg 622, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 287 EP 294 DI 10.1109/NAECON.1998.710129 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800037 ER PT S AU Tolometti, G Saunders, V AF Tolometti, G Saunders, V GP IEEE TI An air force collaborative enterprise environment SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB A collaborative enterprise environment is an application of advanced distributed simulation and information technology in an integrated environment to support technology development, system design, performance, cost, and producibility trade-off analyses throughout the entire product and system engineering life cycle. The Sensors and Information Directorates, Air Force Research Laboratory (AFRL) have initiated a major effort to implement a Collaborative Environment (CF) to provide the framework and development methodology required for affordable and timely technology for the 21(st) Century warfighter, This paper discusses AFRL's efforts to support the new Air Force vision and to maximize its internal business processes through enterprise-wide cooperation. In detail, the paper discusses the need for a CE as a result of Acquisition Reform and Simulation-based Acquisition; describes CE and how the framework supports enterprise-wide collaboration of multidisciplinary expertise; and describes a CE technical architecture and the new technologies that distinguish it from conventional distributed processing systems. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Tolometti, G (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 303 EP 310 DI 10.1109/NAECON.1998.710131 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800039 ER PT S AU Pineiro, LA Biezad, DJ AF Pineiro, LA Biezad, DJ GP IEEE TI Parameter-adaptive model-following for in-flight simulation SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB In-flight simulations are normally accomplished by using control laws which depend on accurate knowledge of the stability derivatives of the host aircraft, Degraded performance may result if the stability derivatives deviate considerably from their presumed valuer. Gain scheduling can compensate far parameter variations, but this form of open-loop compensation may require extensive flight testing far fine tuning. This paper implements an adaptive control law to compensate for changing aircraft parameters. The step-response matrix required, by the control law is identified recursively using a recently developed technique which does not require special "test" signals and which discounts old data depending on the input excitation detected, Tracking fidelity is maintained despite parameter changes. The control design package MATRIXx is used to test the adaptive system, The: performance of the resulting system Is excellent and demonstrates the relative advantages of adaptive controllers far in-flight simulation. C1 USAF, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Pineiro, LA (reprint author), USAF, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 311 EP 319 DI 10.1109/NAECON.1998.710132 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800040 ER PT S AU Ferens, DV AF Ferens, DV GP IEEE TI The conundrum of software estimation models SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc 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 can not 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, AFRL, IFSD, Wright Patterson AFB, OH 45433 USA. RP Ferens, DV (reprint author), USAF, Res Lab, AFRL, IFSD, 2241 Avion Circle,N3F22, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 320 EP 328 DI 10.1109/NAECON.1998.710133 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800041 ER PT S AU Martinsek, D Toussaint, J AF Martinsek, D Toussaint, J GP IEEE TI Integrated precision SAR targeting: A SAR targeting simulation SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc 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, SNRR, Wright Patterson AFB, OH 45433 USA. RP Martinsek, D (reprint author), USAF, Res Lab, SNRR, 2241 Avion Circle,Bldg 620, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 407 EP 413 DI 10.1109/NAECON.1998.710143 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800051 ER PT S AU Blasch, EP Bryant, M AF Blasch, EP Bryant, M GP IEEE TI Information assessment of SAR data for ATR SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB Without successful adaptive multisensor fusion or online registration techniques, automatic target recognition (ATR) algorithms are prone to poor object classifications. Multisensor fusion for a given situation assessment includes identifying measurement information for task completion and reducing image uncertainty in the presence of clutter. By extracting synthetic aperture radar (SAR) image informational features, image registration and target classification is achievable. This paper examines SAR information-theoretic features for target orientation and proposes a method classification. C1 AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. RP Blasch, EP (reprint author), AFRL, SNAT, 2241 Avion Cir, Wright Patterson AFB, OH 45433 USA. NR 0 TC 12 Z9 12 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 414 EP 419 DI 10.1109/NAECON.1998.710144 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800052 ER PT S AU Carr, J Root, J Fetner, R Richmond, R AF Carr, J Root, J Fetner, R Richmond, R GP IEEE TI Operationally capable lidar SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB The Airdrop Ballistic Winds (ABW) team, within the Air Force Research Laboratory, Sensors Directorate, Electro-Optic (EO) Sensor Technology Division, Multi-Function EO Branch (AFRL/SNJM), at Wright-Patterson AFB, Ohio, is preparing to flight test a 2 micron laser radar (lidar) inside a modified C-130 fuel pod. This system, called the Operationally Capable Lidar (OCL), is designed to provide real-time, 3-Dimensional maps of wind fields between the aircraft and the ground, and is expected to significantly improve airdrop accuracy from high altitudes. This paper briefly describes the wind profiling system, the Precision Airdrop Simulation (PADS), and upcoming flight test activities, including the Precision Airdrop Integrated Demonstration which will be conducted at Yuma Proving Grounds (YPG), Arizona, from 29 August through 12 September 1998. C1 USAF, Res Lab, Sensors Directorate, Multi Funct Electroopt Branch, Wright Patterson AFB, OH 45433 USA. RP Carr, J (reprint author), USAF, Res Lab, Sensors Directorate, Multi Funct Electroopt Branch, 3109 P St,Bldg 622, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 428 EP 433 DI 10.1109/NAECON.1998.710146 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800054 ER PT S AU Sisti, AF Farr, SD AF Sisti, AF Farr, SD GP IEEE TI Model abstraction techniques: An intuitive overview SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB The hierarchy of models, as a conceptual framework, is a sound idea. The ultimate plan is for models and simulations at the various levels in the hierarchy to be able to be reused and interconnected with models and simulations at other levels in the hierarchy. The idea stems from their very natural desire to increase the accuracy in these higher-level simulations by incorporating the accuracy of the detailed models. Most efforts to date that have endeavored to increase realism have done so by coupling existing detailed codes; also known as "model integration" A better approach would not involve connecting the detailed code(s) with the aggregate simulation, but rather capturing the essence of the detailed codes into a form compatible with the aggregate simulation (in terms of level of complexity), and connect that version This is the field of research called Model Abstraction which promises to dramatically improve large-scale simulation accuracy without cost to execution time. C1 USAF, Res Lab, IFSB, Rome, NY 13441 USA. RP Sisti, AF (reprint author), USAF, Res Lab, IFSB, 525 Brooks Rd, Rome, NY 13441 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 447 EP 450 DI 10.1109/NAECON.1998.710151 PG 4 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800058 ER PT S AU Concha, LM Read, BC Bawcom, D Jarusewic, P Kadrovach, BA Pedersen, K AF Concha, LM Read, BC Bawcom, D Jarusewic, P Kadrovach, BA Pedersen, K GP IEEE TI Simulation based design of the monobit receiver SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB As defense budgets continue to shrink the Air Force needs an improved method for procurement of weapons electronics systems. We propose strengthening the front end to the procurement process by allowing the users to try out their ideas before committing to a lengthy and expensive procurement cycle. Modeling and Simulation (M&S) shows great promise as a fool to achieve cast effective and requirements focused procurement. Procurers need a simulatable model to allow their users to test a virtual version of their procurement specifications. This paper presents an example of using a VHDL model, documentation, and associated test vectors as a "procurement specification". C1 USAF, Res Lab, Informat Directorate, IFSD,AFRL, Wright Patterson AFB, OH 45433 USA. RP Concha, LM (reprint author), USAF, Res Lab, Informat Directorate, IFSD,AFRL, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 2 U1 0 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 451 EP 453 DI 10.1109/NAECON.1998.710154 PG 3 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800059 ER PT S AU Kadrovach, BA Read, BC Young, FCD Concha, LM Jarusewic, P Pedersen, K Bawcom, D AF Kadrovach, BA Read, BC Young, FCD Concha, LM Jarusewic, P Pedersen, K Bawcom, D GP IEEE TI Hardware simulation with software modeling for enhanced architecture performance analysis SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB Complex simulation-based design efforts suffer from lengthy simulations. It becomes difficult to develop and debug hardware models when the turn around time between development and test results me measured in terms of days or even weeks. A significant lag between development and architecture performance test results can severely hamper the design effort. A strategy fop accurate rapid modeling of a complex digital design is presented The precision of a cycle accurate hardware description language (HDL) model was combined with the speed of software modeling to provide rapid system performance evaluation The hardware model was used to generate timing information and resource requirements from a limited data set. These results were back annotated into the existing algorithm, written in a high-level programming language, in order to generate realistic, full system performance parameters and thus quickly assess the satisfaction of performance constraints by the chosen architecture. C1 USAF, Res Lab, Informat Directorate, IFSD,AFRL, Wright Patterson AFB, OH 45433 USA. RP Kadrovach, BA (reprint author), USAF, Res Lab, Informat Directorate, IFSD,AFRL, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 454 EP 461 DI 10.1109/NAECON.1998.710155 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800060 ER PT S AU Maybeck, PS AF Maybeck, PS GP IEEE TI Failure detection without excessive hardware redundancy SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB Inherent functional redundancy among signals of different sensors can be exploited rather than :resorting exclusively to hardware duplication to achieve fault tolerance and high reliability in data systems, A major objective of this effort has been to demonstrate not only concept feasibility, bur the extent of performance capabilities of a functional redundancy failure detection algorithm. Thus, in a performance improvement program, both missed alarms and false alarms were minimized, The other main goal of the work has beer to develop the failure detection algorithm and an associated performance analysis program into;I systematic and flexible design tool. This tool would then he used to generate an eventual implementation of a tuned and optimized software package far a particular onboard application of functional redundancy for failure detection, Such a useful engineering tool has been developed, and it promises to assist substantially in converting the performance potential of functional redundancy into reality. C1 USAF, Inst Technol, Dept Elect Engn, Washington, DC 20330 USA. RP Maybeck, PS (reprint author), USAF, Inst Technol, Dept Elect Engn, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 463 EP 470 DI 10.1109/NAECON.1998.710160 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800061 ER PT S AU Scarpelli, A AF Scarpelli, A GP IEEE TI Standard VHDL analyzer and intermediate representation SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB To research and develop Computer Aided Design (CAD) tools based on VHDL, an analyzer is necessary to translate the source code into an intermediate representation from which back-end tools can be developed. Whether the analyzer is purchased or built, it is secondary to the research, diverting cost and effort from the intended development. The existence of a standard intermediate representation and a freely available VHDL analyzer that translates source code to that representation allows resources to be focused on the productivity enhancing, back-end tools. The SAVANT project provides VHDL researchers with the tools and compatibility to achieve a significant enhancement in the overall effectiveness of basic CAD-in-VHDL research. C1 IFTA, AFRL, Wright Patterson AFB, OH 45433 USA. RP Scarpelli, A (reprint author), IFTA, AFRL, Bldg 620,2241 Avion Circle Suite 32, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 532 EP 536 DI 10.1109/NAECON.1998.710196 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800071 ER PT S AU Drager, SL Carter, HW Hirsch, HL AF Drager, SL Carter, HW Hirsch, HL GP IEEE TI A VHDL-AMS mixed-signal, mixed-technology design tool SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB This paper describes an Air Force Research Laboratory (formerly Rome Laboratory) development program entitled "Mixed Signal Technology Integration Environment" or "MISTIE." The technologies and tools developed under this program improve a designer's capability to deal with the increasing complexity of today's analog, mixed-signal and mixed-technology designs, as a simulator and design environment for VHDL-AMS (VHDL extensions for Analog and mixed Signal as defined by IEEE 1076.1). The tool suite integrates analog and digital simulation kernels with support tools, to provide a complete analog and mixed signal or mixed technology design environment. C1 USAF, Res Lab, AFRL, IFTC, Rome, NY 13441 USA. RP Drager, SL (reprint author), USAF, Res Lab, AFRL, IFTC, 26 Elect Pkway, Rome, NY 13441 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 552 EP 556 DI 10.1109/NAECON.1998.710201 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800074 ER PT S AU Peterson, GD Mills, M AF Peterson, GD Mills, M GP IEEE TI Mission success: Meeting the systems acquisition challenge with electronic systems design automation. SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB The ever-increasing complexity of electronic systems and interdependency of hardware and software throughout the system life cycle makes it imperative to develop effective electronic design automation languages, methodologies, and tools. Commercial systems face increasing complexity and performance requirements, while achieving decreasing times to market and maximizing profits despite shrinking product life-cycles. Defense systems face similar issues, but must also support life cycles spanning years or decades, thus requiring redesign support or prevention of parts obsolescence challenges. For cost-effective development of systems in this context, design teams need to exploit the best commercial and defense design practices and adapt them as needed to also support concurrent engineering considerations. This paper explores requirements for the emerging system level design language and the methodological needs for it to support multi-disciplinary design, including hardware software co-design, mechanical and packaging support, concurrent engineering, feat, and related issues. By employing these techniques and representations, weapons systems acquisition programs will reduce technical, cost, and schedule risk to help ensure mission success. C1 USAF, Res Lab, Informat Technol Div, Wright Patterson AFB, OH 45433 USA. RP Peterson, GD (reprint author), USAF, Res Lab, Informat Technol Div, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 613 EP 619 DI 10.1109/NAECON.1998.710215 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800083 ER PT S AU Young, FCD Houston, JA AF Young, FCD Houston, JA GP IEEE TI Formal verification and legacy redesign SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc 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 far effective engineering of future weapon systems. C1 USAF, Res Lab, AFRL, IFTA, Wright Patterson AFB, OH 45433 USA. RP Young, FCD (reprint author), USAF, Res Lab, AFRL, IFTA, Wright Patterson AFB, OH 45433 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 627 EP 632 DI 10.1109/NAECON.1998.710218 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800085 ER PT S AU O'Keefe, MJ Hagge, JK Camilletti, RC Rinne, GA White, LK Rates, JT AF O'Keefe, MJ Hagge, JK Camilletti, RC Rinne, GA White, LK Rates, JT GP IEEE TI Packaging of low cost electronic multichip module laminate (MCM-L) assemblies for hermetic-equivalent performance in high reliability avionics applications SO PROCEEDINGS OF THE IEEE 1998 NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE SE IEEE NATIONAL AEROSPACE AND ELECTRONICS CONFERENCE, NAECON LA English DT Proceedings Paper CT IEEE 1998 National Aerospace and Electronics Conference CY JUL 13-17, 1998 CL DAYTON, OH SP IEEE, Dayton Sect, IEEE, Aerosp & Electr Syst Soc AB This paper discusses the results of comparative reliability testing of electronic MultiChip Modules (MCMs) fabricated with laminate substrates (MCM-L) and protected with various bare-die coatings. The demonstration MCMs included flip-chip and wire-bond design versions of the digital portion of a Global Positioning System (GPS) Receiver MCM and an analog MCM for use in general aviation applications. Standard encapsulants and new inorganic coating, DOW Coming's ChipSeal (R) hermetic coating materials, were evaluated using environmental stress exposures for high reliability avionics applications. Full wafer probe testing was performed before and after the supplemental ChipSeal (R) processing and flip-chip wafer bump processing steps. ChipSeal (R) and flip-chip wafer processing steps were shown to cause no device yield degradation on the five different semiconductor wafer lots tested Environmental test results demonstrated that low cost MCM-L units with bare de packaging can be designed for very robust, high reliability applications such as military and commercial avionics. C1 AFRL, SNDI, Wright Patterson AFB, OH 45433 USA. RP O'Keefe, MJ (reprint author), AFRL, SNDI, Bldg 620, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0547-3578 BN 0-7803-4449-9 J9 PROC NAECON IEEE NAT PY 1998 BP 648 EP 655 DI 10.1109/NAECON.1998.710222 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60M UT WOS:000075984800088 ER PT B AU Manasreh, MO Missous, M AF Manasreh, MO Missous, M BE Hou, HQ Sah, RE Pearton, SJ Ren, F Wada, K TI Overview of quantum well infrared detectors SO PROCEEDINGS OF THE SYMPOSIUM ON LIGHT EMITTING DEVICES FOR OPTOELECTRONIC APPLICATIONS AND THE TWENTY-EIGHTH STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Light Emitting Devices for Optoelectronic Applications / 28th State-of-the-Art Program on Compound Semiconductors at 193th Electrochemical-Soc Meeting CY MAY 03-08, 1998 CL SAN DIEGO, CA SP Electrochem Soc, Electr Div AB A review of infrared detectors based on interband and intersubband transitions in intrinsic and extrinsic (n- and p-type) multiple quantum wells that form the basis of modern infrared quantum detectors. The analysis of the results obtained using infrared absorption technique in both type I and Type II quantum wells will be discussed. Recent results recorded for multiple quantum well structures for multi-colors detection will be shown and discussed. C1 USAF, Res Lab, VSSS, Kirtland AFB, NM 87117 USA. RP Manasreh, MO (reprint author), USAF, Res Lab, VSSS, 3550 Aberdeen Ave,SE,Bldg 426, Kirtland AFB, NM 87117 USA. NR 0 TC 6 Z9 6 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-194-3 J9 ELEC SOC S PY 1998 VL 98 IS 2 BP 1 EP 9 PG 9 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing SC Electrochemistry; Engineering; Materials Science GA BL49G UT WOS:000075698000001 ER PT B AU Schuermeyer, F Zampardi, PJ Asbeck, PM AF Schuermeyer, F Zampardi, PJ Asbeck, PM BE Hou, HQ Sah, RE Pearton, SJ Ren, F Wada, K TI InP-based HBTS for optical signal detection SO PROCEEDINGS OF THE SYMPOSIUM ON LIGHT EMITTING DEVICES FOR OPTOELECTRONIC APPLICATIONS AND THE TWENTY-EIGHTH STATE-OF-THE-ART PROGRAM ON COMPOUND SEMICONDUCTORS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT Symposium on Light Emitting Devices for Optoelectronic Applications / 28th State-of-the-Art Program on Compound Semiconductors at 193th Electrochemical-Soc Meeting CY MAY 03-08, 1998 CL SAN DIEGO, CA SP Electrochem Soc, Electr Div AB In this paper we present experimental results on the electro-optical characteristics of InP based heterostructure bipolar transistors (HBTs). We discuss their superior performance as optical signal detectors for high speed applications. The use of an InP HBT based photodetector allows their monolithic integration with amplifying and signal processing circuits. Typical devices use InAlAs emitter structures and InGaAs base layers. The band gap of InGaAs is approximately 0.75 eV, corresponding to absorbption of light with wavelengths shorter than 1.7 mu m. For a wavelength range of 0.95 to 1.7 mu m, the HBT can be used as an optical detector with backside illumination and no changes to the front side metallization is required. Backside illumination is compatible with flip-chip bonding far high-speed packaging. In single heterostructure devices, both electron and hole transport contribute to the photocurrent and the slower holes control the speed of these photodetectors. In double heterostructure HBTs only electron transport contributes to the photocurrent. C1 USAF, Res Lab, AFRL, SNDD, Wright Patterson AFB, OH 45433 USA. RP Schuermeyer, F (reprint author), USAF, Res Lab, AFRL, SNDD, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-194-3 J9 ELEC SOC S PY 1998 VL 98 IS 2 BP 19 EP 28 PG 10 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing SC Electrochemistry; Engineering; Materials Science GA BL49G UT WOS:000075698000003 ER PT S AU Adams, HL Morris, MG VanScotter, JR AF Adams, HL Morris, MG VanScotter, JR BE Blanning, RW King, DR TI Supporting the virtual organization: Implications for e-mail use and policy SO PROCEEDINGS OF THE THIRTY-FIRST HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES, VOL IV: INTERNET AND THE DIGITAL ECONOMY TRACT SE PROCEEDINGS OF THE ANNUAL HAWAII INTERNATIONAL CONFERENCE ON SYSTEM SCIENCES LA English DT Proceedings Paper CT 31st Hawaii International Conference on System Sciences (HICSS-31) CY JAN 06-09, 1998 CL KOHALA COAST, HI SP Univ Hawaii, Coll Business Adm AB Information technology support for the virtual organization involves many facets. Electronic mail technology has been presented as a robust tool which managers can use to communicate effectively with other members of their organization. A field study of 178 Air Force managers was conducted to examine whether those manager's media choices were consistent with Media Richness Theory. Results from the study were largely consistent with suggestions made by Markus [7]. However, study results contradicted Media Richness Theory in that higher level managers did not appear to be more "media sensitive." Organizational contest and social cues are discussed as possible important moderating influences on managers' media choices. C1 USAF, Washington, DC USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1060-3425 BN 0-8186-8255-8 J9 P ANN HICSS PY 1998 BP 121 EP 130 PG 10 WC Computer Science, Information Systems; Information Science & Library Science; Management SC Computer Science; Information Science & Library Science; Business & Economics GA BK43F UT WOS:000072157000014 ER PT B AU Weeks, MR Davis, KJ Lowe, JK Rizzoli, B AF Weeks, MR Davis, KJ Lowe, JK Rizzoli, B BE McClatchey, CA Fowler, KL TI Rush hour at 10,000 feet: USAF pilot training capacity analysis SO PROCEEDINGS OF THE TWENTY-SEVENTH ANNUAL MEETING OF THE WESTERN DECISION SCIENCES INSTITUTE LA English DT Meeting Abstract CT 27th Annual Meeting of the Western-Decision-Sciences-Institute CY APR 07-11, 1998 CL RENO, NV SP Western Decis Sci Inst C1 USAF Acad, Colorado Springs, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU DECISION SCIENCES INST PI ATLANTA PA UNIV PLAZA, ATLANTA, GA 30303 USA PY 1998 BP 124 EP 124 PG 1 WC Business; Business, Finance; Management; Public Administration SC Business & Economics; Public Administration GA BN33N UT WOS:000081655200045 ER PT B AU Deckro, RF Hebert, JE AF Deckro, RF Hebert, JE BE McClatchey, CA Fowler, KL TI Modeling a new product development project SO PROCEEDINGS OF THE TWENTY-SEVENTH ANNUAL MEETING OF THE WESTERN DECISION SCIENCES INSTITUTE LA English DT Proceedings Paper CT 27th Annual Meeting of the Western-Decision-Sciences-Institute CY APR 07-11, 1998 CL RENO, NV SP Western Decis Sci Inst AB This paper outlines a model that investigates balancing the competing needs and requirements of time to market, quality, and new product development costs while considering a firm's competitive objectives. The model is robust enough to consider an array of options, while being driven by the combined objectives of "speed to market" and the need for quality. These two forces are combined through the maximization of overall profit. C1 USAF, Inst Technol, Dept Operat Sci, Ctr Modeling & Simulat Anal, Wright Patterson AFB, OH 45433 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU DECISION SCIENCES INST PI ATLANTA PA UNIV PLAZA, ATLANTA, GA 30303 USA PY 1998 BP 511 EP 514 PG 4 WC Business; Business, Finance; Management; Public Administration SC Business & Economics; Public Administration GA BN33N UT WOS:000081655200172 ER PT B AU Deckro, RF Kloeber, JM Jackson, JA AF Deckro, RF Kloeber, JM Jackson, JA BE McClatchey, CA Fowler, KL TI Communicating post optimality analysis: Visualizing sensitivity analysis SO PROCEEDINGS OF THE TWENTY-SEVENTH ANNUAL MEETING OF THE WESTERN DECISION SCIENCES INSTITUTE LA English DT Proceedings Paper CT 27th Annual Meeting of the Western-Decision-Sciences-Institute CY APR 07-11, 1998 CL RENO, NV SP Western Decis Sci Inst AB The ability to effectively present decision science analysis is a key consideration in assuring that such analyses are utilized. This paper highlights the use of visualization approaches to present standard optimization and post-optimization results. C1 USAF, Inst Technol, Dept Operat Sci, Ctr Modeling Simulat & Anal, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU DECISION SCIENCES INST PI ATLANTA PA UNIV PLAZA, ATLANTA, GA 30303 USA PY 1998 BP 515 EP 517 PG 3 WC Business; Business, Finance; Management; Public Administration SC Business & Economics; Public Administration GA BN33N UT WOS:000081655200173 ER PT S AU Javidi, B Horner, JL AF Javidi, B Horner, JL BE Wolf, E TI Pattern recognition with nonlinear techniques in the Fourier domain SO PROGRESS IN OPTICS, VOL 38 SE Progress in Optics LA English DT Review ID JOINT TRANSFORM CORRELATOR; SPATIAL LIGHT-MODULATOR; FILTER; PLANE; PHASE; PERFORMANCE; SIGNAL; NOISE; DESIGN C1 Univ Connecticut, Dept Elect & Syst Engn, Storrs, CT 06269 USA. USAF, Res Lab, Bedford, MA 01731 USA. RP Javidi, B (reprint author), Univ Connecticut, Dept Elect & Syst Engn, 260 Glenbrook Rd,U-157, Storrs, CT 06269 USA. NR 52 TC 0 Z9 0 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0079-6638 BN 0-444-82907-5 J9 PROG OPTICS JI Prog. Opt. PY 1998 VL 38 BP 343 EP 418 DI 10.1016/S0079-6638(08)70353-6 PG 76 WC Optics SC Optics GA BL54N UT WOS:000075844000005 ER PT S AU Murphy, EA Roadcap, JR AF Murphy, EA Roadcap, JR BE Bissonnette, LR TI Comparison of isoplanatic angles derived from thermosonde and optical measurements SO PROPAGATION AND IMAGING THROUGH THE ATMOSPHERE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Propagation and Imaging Through the Atmosphere II CY JUL 22-23, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE optical turbulence; thermosonde; isoplanometer; isoplanatic angle AB A comparison of isoplanatic angles (theta(0)) derived from (1) balloon-borne in-situ measurements of the index of refraction structure constant (C-n(2)) profiles and (2) remote optical measurements of stellar intensity fluctuations using an isoplanometer is shown. Concurrent data taken over a six day period in the spring of 1986 show reasonably good agreement between the methods considering normal atmospheric variability. Possible reasons for differences between individual measurements are discussed. C1 USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. RP Murphy, EA (reprint author), USAF, Res Lab, VSBC, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 0 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 0-8194-2888-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3433 BP 152 EP 158 DI 10.1117/12.330214 PG 7 WC Meteorology & Atmospheric Sciences; Optics SC Meteorology & Atmospheric Sciences; Optics GA BM19U UT WOS:000078008500015 ER PT S AU Van Caster, TB Welsh, BM Roggemann, MC AF Van Caster, TB Welsh, BM Roggemann, MC BE Bissonnette, LR TI Evaluation of a maximum a-posteriori slope estimator for a Hartmann wavefront sensor. SO PROPAGATION AND IMAGING THROUGH THE ATMOSPHERE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Propagation and Imaging Through the Atmosphere II CY JUL 22-23, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers AB The Hartmann sensor is a popular wavefront sensor (WFS) for measuring the wavefront gradient in the pupil of an adaptive optical telescope. Conventional methods for estimating the wavefront slope within each WFS subaperture rely on a centroid computation of the subaperture detector irradiance distribution. The centroid computation is equivalent to a first moment calculation. A maximum a-posteriori (MAP) slope estimator improves on the conventional centroid estimator by taking advantage of priori knowledge of the subaperture wavefront slope statistics and total irradiance falling on the subaperture array. In order to derive a closed form solution for the MAP estimator, several assumptions were made in a previously published paper. These assumptions include: infinitely small pixels on the subaperture detector arrays, no read noise in the detection process, and no irradiance spillover between adjacent subapertures. By implementing the Hartmann WFS and MAP estimator in a detailed computer simulation, the performance of the MAP estimator was evaluated using realizable WFS parameters. The simulation shows that even when the assumptions used to derive the MAP slope estimator are relaxed, the MAP estimator outperforms the conventional subaperture centroid estimator. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Van Caster, TB (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2888-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3433 BP 262 EP 272 DI 10.1117/12.330224 PG 11 WC Meteorology & Atmospheric Sciences; Optics SC Meteorology & Atmospheric Sciences; Optics GA BM19U UT WOS:000078008500027 ER PT S AU Ford, SD Welsh, BM Roggemann, MC AF Ford, SD Welsh, BM Roggemann, MC BE Bissonnette, LR TI Constrained least-squares incorporating wave-front sensing SO PROPAGATION AND IMAGING THROUGH THE ATMOSPHERE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Propagation and Imaging Through the Atmosphere II CY JUL 22-23, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE atmospheric turbulence; constrained least-squares; deconvolution from wavefront sensing AB We address the optimal processing of astronomical images using the deconvolution from wave-front sensing technique (DWFS). A constrained least-squares (CLS) solution which incorporates ensemble-averaged DWFS data is derived using Lagrange minimization. The new estimator requires DWFS data, noise statistics, optical transfer function (OTF) statistics, and a constraint. The constraint can be chosen such that the algorithm selects a conventional regularization constant automatically. No ad hoc parameter tuning is necessary. The algorithm uses an iterative Newton-Raphson minimization to determine the optimal Lagrange multiplier. Computer simulation of a Im telescope imaging through atmospheric turbulence is used to test the estimation scheme. CLS object estimates are compared with the corresponding long exposure images. The CLS algorithm provides images with superior resolution and is computationally inexpensive, converging to a solution in less than 10 iterations. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Ford, SD (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2888-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3433 BP 273 EP 284 DI 10.1117/12.330225 PG 12 WC Meteorology & Atmospheric Sciences; Optics SC Meteorology & Atmospheric Sciences; Optics GA BM19U UT WOS:000078008500028 ER PT S AU Foltz, TM Welsh, BM AF Foltz, TM Welsh, BM BE Bissonnette, LR TI A scalar Wiener filter based on discrete trigonometric transforms and symmetric convolution SO PROPAGATION AND IMAGING THROUGH THE ATMOSPHERE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Propagation and Imaging Through the Atmosphere II CY JUL 22-23, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE image reconstruction; Wiener filtering; symmetric convolution; discrete trigonometric transforms AB This paper presents a scalar Wiener filter derived in the transform domain of discrete trigonometric transforms. The implementation of the filter is through symmetric convolution, the underlying form of convolution for discrete trigonometric transforms. The symmetric convolution of two sequences is equivalent to their multiplication in the transform domain of discrete trigonometric transforms. This symmetric convolution-multiplication property and the fact that a type-II discrete cosine transform is asymptotically equivalent to the eigenvectors of the correlation matrix of a Markov-I process allows this scalar Wiener filter to be nearly optimum for Markov-I object models. The performance of the filter is analyzed for the case of recovering an object corrupted by a two-dimensional Gaussian filter in the presence of noise. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Foltz, TM (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2888-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3433 BP 285 EP 295 DI 10.1117/12.330226 PG 11 WC Meteorology & Atmospheric Sciences; Optics SC Meteorology & Atmospheric Sciences; Optics GA BM19U UT WOS:000078008500029 ER PT S AU Whiteley, MR Welsh, BM Roggemann, MC AF Whiteley, MR Welsh, BM Roggemann, MC BE Bissonnette, LR TI Tilt compensation performance enhancement using off-axis higher-order modal wave-front measurements SO PROPAGATION AND IMAGING THROUGH THE ATMOSPHERE II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Propagation and Imaging Through the Atmosphere II CY JUL 22-23, 1998 CL SAN DIEGO, CA SP Soc Photo Opt Instrumentat Engineers DE tilt compensation; optimal estimation; laser beacons; anisoplanatism; adaptive optics AB Tilt compensation performance is generally suboptimal when phase measurements from natural or laser guide stars are used as the conjugate phase in an adaptive optics system. Optimal compensation is obtained when the conjugate phase coefficients are estimated from beacon measurements, given knowledge of the correlation between the on-axis object phase and the beacon measurements. In this work, optimal compensation theory is applied to tilt correction for the case of an off-axis beacon. Since off-axis higher-order modes are correlated with the on-axis tilt components, a performance gain can be realized when the tilt estimator includes higher-order modal measurements. For natural guide star compensation, it is shown that equivalent tilt compensation can be achieved at beacon offsets that are three times larger when higher-order modes through Zernike 15 are used in the tilt estimator. For a laser guide star, while tilt information cannot be measured directly due to beam reciprocity, off-axis higher-order modal measurements can be used to estimate tilt components, leading to a maximum Strehl ratio of approximately 0.3 for D/r(0) = 4 and L-0/D = 10. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Whiteley, MR (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2888-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3433 BP 308 EP 319 DI 10.1117/12.330238 PG 12 WC Meteorology & Atmospheric Sciences; Optics SC Meteorology & Atmospheric Sciences; Optics GA BM19U UT WOS:000078008500031 ER PT B AU Taylor, EW Paxton, AH Schone, H Carson, RF Bristow, J Lehman, JA Hibbs-Brenner, MK Morgan, RA AF Taylor, EW Paxton, AH Schone, H Carson, RF Bristow, J Lehman, JA Hibbs-Brenner, MK Morgan, RA GP IEEE TI In vacuo responses of an AlGaAs vertical cavity surface emitting laser irradiated by 4.5 MeV protons SO RADECS 97: FOURTH EUROPEAN CONFERENCE ON RADIATION AND ITS EFFECTS ON COMPONENTS AND SYSTEMS LA English DT Proceedings Paper CT 4th European Conference on Radiation and its Effects on Components and Systems (RADECS 97) CY SEP 15-19, 1997 CL CANNES, FRANCE SP Thomson CSF, Aerospatiale Espace & Def, TEMIC Semiconductors, CEA/DAM, Ministere Culture, Sandia Natl Labs AB Vertical cavity surface emitting lasers (VCSELs) have high potential for space applications, yet little is known of their sensitivity to radiation under vacuum conditions. The first observations of a commercially available proton implanted quantum well AlGaAs VCSEL operating at 850 nm in vacuo and irradiated by 4.5 MeV protons by a scanning ion microbeam is presented. Degradation of L-I-V responses at a proton dose of 1.19 MGy are discussed with particular attention drawn to heating arising from increased nonradiative carrier recombination and that resulting from the vacuum environment. C1 Kirtland AFB, VTMC, Photon Res Grp, Air Force Phillips Lab, Kirtland AFB, NM 87117 USA. RP Taylor, EW (reprint author), Kirtland AFB, VTMC, Photon Res Grp, Air Force Phillips Lab, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4071-X PY 1998 BP 382 EP 385 DI 10.1109/RADECS.1997.698946 PG 4 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BL38P UT WOS:000075341800065 ER PT B AU Cordell, T Kinra, V Thompson, D Rummel, W AF Cordell, T Kinra, V Thompson, D Rummel, W BE Thompson, DO Chimenti, DE TI NDE: A full spectrum technology SO REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION, VOLS 17A AND 17B LA English DT Proceedings Paper CT Annual Review of Progress in Quantitative Nondestructive Evaluation CY JUL 27-AUG 01, 1997 CL SAN DIEGO, CA SP Iowa State Univ, Ctr NDE, US DOE, Ames Lab, Amer Soc Nondestruct Testing, Natl Inst Stand & Technol, FAA, Natl Sci Fdn Ind, Univ Cooperat Res Ctr C1 USAF, Wright Lab, Met Ceram & NDE Div, Wright Patterson AFB, OH 45433 USA. RP Cordell, T (reprint author), USAF, Wright Lab, Met Ceram & NDE Div, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PRESS DIV PLENUM PUBLISHING CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-45901-9 PY 1998 BP 1099 EP 1107 PG 9 WC Engineering, Electrical & Electronic; Engineering, Mechanical; Materials Science, Ceramics; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Materials Science, Composites SC Engineering; Materials Science GA BL11N UT WOS:000074324500142 ER PT B AU Moore, TM AF Moore, TM BE Demsetz, LA Bryne, RH Wetzel, JP TI All purpose Remote Transport System (ARTS) for active range clearance, force protection, and remediation SO ROBOTICS 98 LA English DT Proceedings Paper CT 3rd ASCE Speciality Conference on Robotics for Challenging Environments (Robotics 98) CY APR 26-30, 1998 CL ALBUQUERQUE, NM SP Amer Soc Civil Engineers, Aerospace Div, NASA, Natl Aeronaut Soc, Amer Astronaut Soc, Amer Inst Architects, Sandia Natl Labs, Bechtel Corp, Fluor Daniel Corp AB The Air Force Research Laboratory (AFRL) in cooperation with Headquarters Air Combat Command and the 99(th) Civil Engineering Group, Nevada Test Ranges has developed a robotics platform capable of carrying a suite of munitions disposal and range maintenance tools. The purpose of this paper is to outline the development and testing of the system and advocate continued research into the automation of UXO clearance, range maintenance, remediation and force protection. The All-purpose Remote Transport System (ARTS) consists of a low cost survivable platform capable of remote operations at distances of up to three miles. Two versions of this system have been fielded: one for active range clearance and one for force protection. C1 USAF, Res Lab, Robot Res Grp, Air Base Technol Branch, Tyndall AFB, FL 32403 USA. RP Moore, TM (reprint author), USAF, Res Lab, Robot Res Grp, Air Base Technol Branch, 139 Barnes Dr,Suite 2, Tyndall AFB, FL 32403 USA. NR 0 TC 0 Z9 0 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 0-7844-0337-6 PY 1998 BP 120 EP 125 PG 2 WC Automation & Control Systems; Engineering, Civil SC Automation & Control Systems; Engineering GA BM53M UT WOS:000079075400018 ER PT B AU Miller, CE AF Miller, CE BE Demsetz, LA Bryne, RH Wetzel, JP TI A modular robotic vehicle control system using the DeviceNet (R) Controller Area Network SO ROBOTICS 98 LA English DT Proceedings Paper CT 3rd ASCE Speciality Conference on Robotics for Challenging Environments (Robotics 98) CY APR 26-30, 1998 CL ALBUQUERQUE, NM SP Amer Soc Civil Engineers, Aerospace Div, NASA, Natl Aeronaut Soc, Amer Astronaut Soc, Amer Inst Architects, Sandia Natl Labs, Bechtel Corp, Fluor Daniel Corp AB The Construction Automation and Robotics Research Laboratory of USAF Wright Laboratory Air Base Technology Branch (WL/FIVC) is currently developing technologies and robotic systems to be used in hazardous operations. Each system requires a robotic vehicle that can be controlled remotely or can operate autonomously. In the simplest case, teleoperation, the vehicle requires an on-board control computer linked to a joystick box via RF modems. For autonomous operation, other components must be added to the vehicle and to the Operator Control Unit (OCU). Autonomous operation requires the addition of the Mission Specific Subsystem (MSS) on the vehicle and a display computer on the OCU. The Vehicle Control Unit (VCU), Autonomous Interface Unit (AIU) and the MSS components have been designed to be as generic as possible with respect to various vehicles. On previous robotic vehicles, a unique computer system and software has been developed on a case-by-case basis. Our current modular system is comprised of a control computer, software, and external sensors that can be applied on a generic basis from one vehicle platform to the next reducing duplication of effort. This Robotic Control System (RCS) has been developed using the DeviceNet(R) Controller Area Network (CAN bus). The VCU and AIU use rugged embedded PC/104 hardware and the MSS is based on VME multi-processor technology. The DeviseNet(R) network is a serial bus with a data rate of 500 Kbps and eliminates discrete point-to-point wiring to connect sensors or actuators to the control computers. The vehicle control and sensor interface software resides on solid state disks in the VCU and AIU, which automatically boots upon power up. The software, upon initialization reads and parses an ASCII text vehicle configuration file. This file describes the vehicle and the associated DeviceNet(R) nodes. When a new vehicle is to be made robotic, this configuration file is virtually the only software component on the VCU and AIU that needs to be modified. C1 Wright Lab, Robot & Automat Grp, Tyndall AFB, FL 32403 USA. RP Miller, CE (reprint author), Wright Lab, Robot & Automat Grp, Tyndall AFB, FL 32403 USA. NR 0 TC 0 Z9 0 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 0-7844-0337-6 PY 1998 BP 154 EP 160 PG 3 WC Automation & Control Systems; Engineering, Civil SC Automation & Control Systems; Engineering GA BM53M UT WOS:000079075400023 ER PT S AU Lott, JA AF Lott, JA BE Wang, Q Davis, LJ Forouhar, S TI Design of semiconductor microcavity emitters and detectors for optical memory and interconnect systems SO SEMICONDUCTOR LASERS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Semiconductor Lasers III CY SEP 16-18, 1998 CL BEIJING, PEOPLES R CHINA SP SPIE, COS, COEMA DE vertical cavity surface emitting lasers; light-emitting diodes; photodetectors; optoelectronic integrated circuits AB This paper presents a numerical design study of monolithically integrated microcavity detecting and emitting devices for applications in optical memory and interconnect systems. Combinations of 650 nm AlGaInP/AlGaAs resonant cavity light-emitting diodes and vertical cavity surface emitting lasers are examined. The device structures include resonant cavity p-i-n photodetectors embedded within distributed Bra,og reflector mirrors. The photodetectors consist of an undoped quantum well absorbing layer positioned at an antinode of the resonant standing wave. Classical spontaneous and stimulated emission intracavity absorption models are developed to estimate the embedded photodetector spectral responsivity. This embedded photodetector configuration provides an effective means for studying the spontaneous and stimulated emission components of microcavity light emitting devices. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Lott, JA (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-3008-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3547 BP 168 EP 178 DI 10.1117/12.319637 PG 11 WC Optics; Physics, Applied; Physics, Condensed Matter SC Optics; Physics GA BL82M UT WOS:000076839400030 ER PT J AU Amato, AA Collins, MP AF Amato, AA Collins, MP TI Neuropathies associated with malignancy SO SEMINARS IN NEUROLOGY LA English DT Review DE neuropathy; paraneoplastic neuropathy; motor neuron disease; cancer; malignancy; chemotherapy ID BONE-MARROW TRANSPLANTATION; CELL LUNG-CANCER; MOTOR-NEURON DISEASE; INDUCED PERIPHERAL NEUROPATHY; STIFF-MAN SYNDROME; AMYOTROPHIC-LATERAL-SCLEROSIS; POST-HERPETIC NEURALGIA; GUILLAIN-BARRE-SYNDROME; VERSUS-HOST DISEASE; CISPLATIN-INDUCED NEUROTOXICITY AB Patients with malignancy can develop peripheral neuropathies as (1) a direct effect of the cancer by invasion or compression of nerves, (2) a remote or paraneoplastic effect, or (3) an iatrogenic effect of treatment. Focal or multifocal cranial neuropathies, radiculopathies, and plexopathies typically result from tumor infiltration, herpes tester infection, or radiation-induced injury. Sensorimotor polyneuropathies are the most frequently encountered peripheral nerve syndromes, but motor neuropathies, sensory neuronopathies, polyradiculoneuropathies, and autonomic neuropathies can also occur. Although uncommon, paraneoplastic mechanisms should be considered in a patient with malignancy and an associated peripheral nerve disorder, especially in the setting of small-cell lung cancer or lymphoproliferative cancer. Toxic neuropathies occur with exposure to several chemotherapeutic agents, including the vinca alkaloids, cisplatin, taxanes, and suramin, These neuropathies are usually dose-related, sensory-predominant, and at least partially reversible, with an axonopathic or ganglionopathic mechanism. Suramin is unique in causing subacute, demyelinating polyradiculoneuropathy. C1 Univ Texas, Hlth Sci Ctr, Dept Med Neurol, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, Neuromuscular Dis Sect, Dept Neurol, San Antonio, TX 78236 USA. RP Amato, AA (reprint author), Univ Texas, Hlth Sci Ctr, Dept Med Neurol, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. NR 279 TC 26 Z9 27 U1 0 U2 1 PU THIEME MEDICAL PUBL INC PI NEW YORK PA 333 SEVENTH AVE, NEW YORK, NY 10001 USA SN 0271-8235 J9 SEMIN NEUROL JI Semin. Neurol. PY 1998 VL 18 IS 1 BP 125 EP 144 DI 10.1055/s-2008-1040868 PG 20 WC Clinical Neurology SC Neurosciences & Neurology GA 172QK UT WOS:000078935500014 PM 9562674 ER PT B AU Rodrigue, SM Bash, JL Haenni, MG AF Rodrigue, SM Bash, JL Haenni, MG GP IEEE TI Next generation broadband digital receiver technology SO SENSING THE WORLD: ANALOG SENSORS & SYSTEMS ACROSS THE SPECTRUM LA English DT Proceedings Paper CT 15th Annual AESS/IEEE Dayton-Section Symposium on Sensing the World: Analog Sensors & Systems Across the Spectrum CY MAY 14-15, 1998 CL FAIRBORN, OH SP IEEE, Aerosp & Electr Syst Soc, Dayton Chapter, IEEE, Dayton Sect AB (U) Current Electronic Support Measure (ESM) receiver functions on combat, reconnaissance and surveillance aircraft are being tasked to provide more threat information, more accurately, and on a shorter timeline. At the same time, the complexity of the signal environment is increasing. Today's ESM receiver technology is based on analog components that are costly to manufacture, have large size, weight and power (SWAP) characteristics, have limited performance and are costly to maintain. Because of these limitations, it is not practical to improve the performance of current ESM receiver systems nor is it practical to build new low cost high, high performance systems using analog technology. The Objective of this paper is to present an approach to build a broadband digital ESM receiver that will provide a low cost, high performance solution for tomorrow's platforms. C1 USAF, Res Lab, Washington, DC 20330 USA. RP Rodrigue, SM (reprint author), USAF, Res Lab, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4922-9 PY 1998 BP 13 EP 20 DI 10.1109/DAYTON.1998.694550 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60L UT WOS:000075983800002 ER PT B AU Martinez, EJ Bobb, RL AF Martinez, EJ Bobb, RL GP IEEE TI High performance Analog-to-Digital Converter technology for military avionics applications SO SENSING THE WORLD: ANALOG SENSORS & SYSTEMS ACROSS THE SPECTRUM LA English DT Proceedings Paper CT 15th Annual AESS/IEEE Dayton-Section Symposium on Sensing the World: Analog Sensors & Systems Across the Spectrum CY MAY 14-15, 1998 CL FAIRBORN, OH SP IEEE, Aerosp & Electr Syst Soc, Dayton Chapter, IEEE, Dayton Sect AB The signal processing requirements of military avionics systems are constantly increasing to meet the threats of the next century. This is especially true as the digital interface moves closer to the sensor/antenna and the Analog-to-Digital Converter (ADC) performance requirements become a major contributor to spaceborne data and signal/sensor processors and mission management specifications. The benefits of moving the digital interface closer to the sensor/antenna in avionics systems can be classified in four different categories: affordability, reliability and maintainability, physical, and performance. This reduction in RF downconversion stages as the digital interface mi,orates toward the sensor can result in some difficult ADC requirements that can not currently be met by commercial technologies. It is the intention of this presentation to expose the aerospace community to these emerging requirements for radar, communication and navigation (CNI), and electronic warfare missions. In addition to these requirements, we are presenting some examples of current state-of-the-art ADCs, their technology limitations, and briefly discuss potential applications in avionics systems. We have also included in this presentation a brief discussion on the fundamental and physical limitations that impair the progress of current and future ADC technologies. This presentation will conclude with a technology forecast, and an estimate on ADC availability for future avionics systems. C1 USAF, Aerosp Components Div, Res Lab, AFRL,SNDM, Wright Patterson AFB, OH 45433 USA. RP Martinez, EJ (reprint author), USAF, Aerosp Components Div, Res Lab, AFRL,SNDM, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4922-9 PY 1998 BP 21 EP 36 DI 10.1109/DAYTON.1998.694551 PG 16 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60L UT WOS:000075983800003 ER PT B AU McManamon, PF AF McManamon, PF GP IEEE TI Dual use opportunities for EO sensors - How to afford military sensing SO SENSING THE WORLD: ANALOG SENSORS & SYSTEMS ACROSS THE SPECTRUM LA English DT Proceedings Paper CT 15th Annual AESS/IEEE Dayton-Section Symposium on Sensing the World: Analog Sensors & Systems Across the Spectrum CY MAY 14-15, 1998 CL FAIRBORN, OH SP IEEE, Aerosp & Electr Syst Soc, Dayton Chapter, IEEE, Dayton Sect AB There are many dual use opportunities for Electro-optical sensors. A number of EO sensors have already been transitioned from military development to commercial applications. Many more need to be transitioned for the military to be able to afford the sensing technology that it needs. The old paradigm was that the military developed what it needed and then produced it. Companies then exploited that development for commercial markets. The new paradigm will be that the military asks for participation from companies with commercial interests even in the development phase. In addition, the military will plan its developments to promote a volume manufacturing market as a method of getting production costs down to affordable values. This has to be carefully planned to preserve a military edge over potential adversaries. With rapid technical progress the military edge occurs simply because we are " first to market" with the military hardware. In a slower technical development this edge is not enough. C1 USAF, Res Lab, Sensors Directorate, SNJ, Wright Patterson AFB, OH 45433 USA. RP McManamon, PF (reprint author), USAF, Res Lab, Sensors Directorate, SNJ, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4922-9 PY 1998 BP 49 EP 52 DI 10.1109/DAYTON.1998.694554 PG 4 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60L UT WOS:000075983800006 ER PT B AU McManamon, PF AF McManamon, PF GP IEEE TI Laser radar development SO SENSING THE WORLD: ANALOG SENSORS & SYSTEMS ACROSS THE SPECTRUM LA English DT Proceedings Paper CT 15th Annual AESS/IEEE Dayton-Section Symposium on Sensing the World: Analog Sensors & Systems Across the Spectrum CY MAY 14-15, 1998 CL FAIRBORN, OH SP IEEE, Aerosp & Electr Syst Soc, Dayton Chapter, IEEE, Dayton Sect DE sensing; affordable sensing; multifunction sensing; multifunction EO; multidiscriminant sensing; modular sensors; laser radar; ladar; lidar; multidiscriminant laser radar AB This paper discusses the trends in laser radar development. Applications include reconnaissance and targeting from airborne and spaceborne platforms. A multifunction airborne sensor system, which includes a laser radar function with many modes, is defined. A multidiscriminant space borne laser radar is also described and its feasibility is assessed. A number proposed and existing Air Force programs to develop laser radar technology are described. C1 USAF, Res Lab, Sensors Directorate, SNJ, Wright Patterson AFB, OH 45433 USA. RP McManamon, PF (reprint author), USAF, Res Lab, Sensors Directorate, SNJ, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 3 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4922-9 PY 1998 BP 53 EP 60 DI 10.1109/DAYTON.1998.694555 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60L UT WOS:000075983800007 ER PT B AU Eismann, MT AF Eismann, MT GP IEEE TI Thermal spectral imaging for air-to-ground target detection SO SENSING THE WORLD: ANALOG SENSORS & SYSTEMS ACROSS THE SPECTRUM LA English DT Proceedings Paper CT 15th Annual AESS/IEEE Dayton-Section Symposium on Sensing the World: Analog Sensors & Systems Across the Spectrum CY MAY 14-15, 1998 CL FAIRBORN, OH SP IEEE, Aerosp & Electr Syst Soc, Dayton Chapter, IEEE, Dayton Sect C1 USAF, Res Lab, SNJT, Wright Patterson AFB, OH 45433 USA. RP Eismann, MT (reprint author), USAF, Res Lab, SNJT, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-4922-9 PY 1998 BP 79 EP 96 PG 18 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BL60L UT WOS:000075983800010 ER PT J AU Burns, DM Bright, VM AF Burns, DM Bright, VM TI Development of microelectromechanical variable blaze gratings SO SENSORS AND ACTUATORS A-PHYSICAL LA English DT Article DE MEMS; gratings; micro-optics; polysilicon AB Two types of microelectromechanical variable blaze gratings (VBGs) have been designed, modeled, fabricated, and tested. The gratings operate by adjusting the blaze angle of each slat so specular reflection of the incident light matches a particular grating diffraction order. The VBG blaze angle is adjustable with either electrostatic or thermal actuators. VBGs direct incident light in discrete directions, and are useful for steering light with beam diameters greater than 1 mm and power levels greater than 1 W. Both electrostatically and thermally actuated VBGs have been constructed from gold and polysilicon using a surface-micromachining process and tested with a 20 mW continuous wave HeNe laser operating at a wavelength of 632.8 nm. The diffraction efficiency and far-field pattern have been modeled and measured. Drive voltages for both types of gratings are measured as a function of blaze angle and selected diffraction order. (C) 1998 Elsevier Science S.A. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Bright, VM (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 16 TC 28 Z9 29 U1 2 U2 3 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 1 PY 1998 VL 64 IS 1 BP 7 EP 15 DI 10.1016/S0924-4247(98)80052-6 PG 9 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA YM107 UT WOS:000071029100002 ER PT S AU Peters, KW Turner, TS Tyo, JS AF Peters, KW Turner, TS Tyo, JS BE Fujisada, H TI Portable visible imaging spectropolarimeter for remote sensing applications SO SENSORS, SYSTEMS, AND NEXT-GENERATION SATELLITES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensors, Systems, and Next-Generation Satellites II CY SEP 21-24, 1998 CL BARCELONA, SPAIN SP CNR, NASA, EOS, Commiss European Communities, SPIE - Int Soc Opt Engn DE hyperspectral; polarimetry; spectropolarimetric imaging; remote sensing ID FOURIER-TRANSFORM SPECTROMETER AB We have developed a laboratory breadboard spectropolarimetric hyperspectral imaging sensor for operation in the visible-near IR waveband to demonstrate its potential for future airborne and spaceborne systems. An existing spatially modulated imaging Fourier transform spectrometer was modified by the addition of polarization analyzer components. Images collected by the focal plane array vary spatially in one dimension and spectrally in the other. A scanning slit simulates a pushbroom scanning mode for the second spatial dimension. Polarimetric sensing is accomplished using two liquid crystal variable retarders in tandem followed by a linear polarizer. To recover the complete Stokes vector four images, each with distinct combinations of retardances, are collected for each slit position. Sample images are presented. C1 USAF, Res Lab, VSSS, Kirtland AFB, NM 87117 USA. RP Peters, KW (reprint author), USAF, Res Lab, VSSS, 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 0-8194-2957-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3498 BP 223 EP 230 DI 10.1117/12.333633 PG 8 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM37Y UT WOS:000078533900023 ER PT S AU Voelz, DG McMackin, L Boger, JK Fetrow, MP Bartolac, TJ AF Voelz, DG McMackin, L Boger, JK Fetrow, MP Bartolac, TJ BE Fujisada, H TI Optical heterodyne arrays for large space optics figure sensing SO SENSORS, SYSTEMS, AND NEXT-GENERATION SATELLITES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensors, Systems, and Next-Generation Satellites II CY SEP 21-24, 1998 CL BARCELONA, SPAIN SP CNR, NASA, EOS, Commiss European Communities, SPIE - Int Soc Opt Engn DE heterodyne array; wave front sensing; opto-electronics; interferometry; lightweight optics AB It is envisioned that large, lightweight, optical mirrors for use in space will require onboard instrumentation for measuring and controlling the gross aspects of the mirror surface figure. An optical heterodyne array is well-suited for the figure sensing portion of this operation. The basic principles of heterodyne wave front sensing are reviewed and the advantages of this approach are highlighted. We describe the development of a dedicated circuitry module for integration with a sensor array for performing heterodyne array phase measurements. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Voelz, DG (reprint author), USAF, Res Lab, 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 0-8194-2957-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3498 BP 430 EP 433 DI 10.1117/12.333656 PG 4 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM37Y UT WOS:000078533900044 ER PT S AU McMackin, L Voelz, DG Fetrow, MP McIntire, H Bishop, KP Kellum, MJ AF McMackin, L Voelz, DG Fetrow, MP McIntire, H Bishop, KP Kellum, MJ BE Fujisada, H TI Multi-wavelength heterodyne array system for large space optics control SO SENSORS, SYSTEMS, AND NEXT-GENERATION SATELLITES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensors, Systems, and Next-Generation Satellites II CY SEP 21-24, 1998 CL BARCELONA, SPAIN SP CNR, NASA, EOS, Commiss European Communities, SPIE - Int Soc Opt Engn DE heterodyne interferometry; phase measurement; surface profiling; adaptive optics; automated control systems ID PHASE-SHIFTING INTERFEROMETRY; 2-WAVELENGTH AB Large, lightweight optical mirrors for space applications will require systems for controlling the gross aspects of the mirror surface figure. We have developed an autonomously operating wavefront measurement system based on dual-wavelength heterodyne distance measurement techniques combined with heterodyne array imaging. A key feature of the technique is variable optical path length measurement sensitivity that allows the system to measure surface figure errors ranging from thousands of wavelengths down to fractions of a wavelength. Automatic sensitivity tuning combined with completely digital phase measurement over the entire surface allows the integration of this device in automated sensing and optical correction schemes. It is particularly suited for the measurement and control of spatially and temporally variable optical surfaces of the kind that would be found in a space-based adaptive optics system. In this paper we demonstrate aspects of the automated super-heterodyne system on an optical surface with surface profile structure height that varies from micron to mm sized features. We describe the hardware and software design of the heterodyne based measurement system that enable it to choose the appropriate synthetic wavelength to measure different areas of the surface profile. Spatial processing methods are discussed that allow the system to merge segments of large scale images that have been measured at different synthetic wavelengths. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP McMackin, L (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 7 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 0-8194-2957-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3498 BP 434 EP 445 DI 10.1117/12.333657 PG 12 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM37Y UT WOS:000078533900045 ER PT S AU Gamiz, VL AF Gamiz, VL BE Fujisada, H TI Performance of a four channel polarimeter with very low light level detection SO SENSORS, SYSTEMS, AND NEXT-GENERATION SATELLITES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensors, Systems, and Next-Generation Satellites II CY SEP 21-24, 1998 CL BARCELONA, SPAIN SP CNR, NASA, EOS, Commiss European Communities, SPIE - Int Soc Opt Engn DE polarized light; polarimetry; Mueller calculus; statistical optics AB We examine the low light level performance of a four-channel polarimeter with a single photon counting sensor associated with each channel. Specifically, we investigate how the detection noise propagates through the polarimeter calibration matrix and influences the estimation of I-1 and I-2, the intensities in two orthogonal polarization states and, delta, the phase delay between the two orthogonal states. The error in estimating the phase delay is first derived in the small angle approximation for low light levels. The approximation is removed by deriving a general formalism valid for arbitrary light levels including very low light levels. A specific polarimeter design is examined and quantitative examples are shown and discussed for that polarimeter. C1 USAF, Res Lab, Surveillance Technol Branch, DEBS, Kirtland AFB, NM 87117 USA. RP Gamiz, VL (reprint author), USAF, Res Lab, Surveillance Technol Branch, DEBS, Bldg 422,3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 4 TC 0 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 0-8194-2957-0 J9 P SOC PHOTO-OPT INS PY 1998 VL 3498 BP 446 EP 457 DI 10.1117/12.333658 PG 12 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM37Y UT WOS:000078533900046 ER PT J AU Byrd, L Camden, MP Maddux, GE Simmons, LW AF Byrd, L Camden, MP Maddux, GE Simmons, LW TI Random amplitude fatigue life of electroformed nickel micro-channel heat exchanger coupons SO SHOCK AND VIBRATION LA English DT Article AB The use of micro-channel heat exchangers (MCHEX) with coolant flow passage diameters less than 1 mm has been proposed for heat flux, weight, or volume limited environments. This paper presents room temperature, random amplitude, epsilon - N (strain versus number of cycles to failure) curves for MCHEX coupons formed by electroplating nickel on a suitable form. These coupons are unique in two aspects; the microstructure formed by electroplating and the presence of holes as an integral part of the structure. The hole diameters range from approximately 10% to 50% to the specimen thickness. The fatigue life of electroformed nickel can be estimated from constant amplitude data using the formulation presented. The heat exchangers with channels parallel to the coupon direction have a lower fatigue life than the solid material. C1 USAF, Struct Div, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. RP Byrd, L (reprint author), USAF, Struct Div, Air Vehicles Directorate, 2790 D St,Bldg 65, Wright Patterson AFB, OH 45433 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU IOS PRESS PI AMSTERDAM PA VAN DIEMENSTRAAT 94, 1013 CN AMSTERDAM, NETHERLANDS SN 1070-9622 J9 SHOCK VIB JI Shock Vib. PY 1998 VL 5 IS 2 BP 103 EP 110 PG 8 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 121QT UT WOS:000076025400003 ER PT S AU Silverman, J Caefer, CE DiSalvo, S Vickers, VE AF Silverman, J Caefer, CE DiSalvo, S Vickers, VE BE Drummond, OE TI Temporal filtering for point target detection in staring IR imagery: II. recursive variance filter SO SIGNAL AND DATA PROCESSING OF SMALL TARGETS 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Signal and Data Processing of Small Targets CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE staring infrared; point target detection; recursive variance filter; temporal processing AB We describe a recursive temporal filter based on a running estimate of the temporal variance followed by removal of the baseline (long-time) variance of each pixel. The algorithm is designed for detection/tracking of "point" targets moving at sub-pixel/frame velocities, 0.02 to 0.50 p/f, in noise-dominated scenarios on staring IR camera data. The technique responds to targets of either polarity. A preprocessing technique, morphological in origin but implemented by median filters, further improves the S/N sensitivity of the algorithm while restricting the results to positive contrast targets. The computationally simple algorithm has been implemented in hardware and real-time operation is in evaluation. The performance is characterized by some specific examples as well as plots over our extensive database of real data. Detection down to S/N similar to 3 or less and sensitivity to the appropriate range of velocities is demonstrated. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Silverman, J (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 0 TC 17 Z9 18 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 0-8194-2822-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3373 BP 44 EP 53 DI 10.1117/12.324648 PG 10 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL66J UT WOS:000076232400006 ER PT S AU Caefer, CE Silverman, J Mooney, JM DiSalvo, S Taylor, RW AF Caefer, CE Silverman, J Mooney, JM DiSalvo, S Taylor, RW BE Drummond, OE TI Temporal filtering for point target detection in staring IR imagery: I. Damped sinusoid filters SO SIGNAL AND DATA PROCESSING OF SMALL TARGETS 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Signal and Data Processing of Small Targets CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE staring IR camera; point target detection; cloud clutter; triple temporal filter; algorithm fusion AB In an earlier conference, we introduced a powerful class of temporal filters, which have outstanding signal to clutter gains in evolving cloud scenes. The basic temporal filter is a zero-mean damped sinusoid, implemented recursively. Our final algorithm, a triple temporal filter, consists of a sequence of two zero-mean damped sinusoids followed by an exponential averaging filter along with an edge suppression factor. The algorithm was designed, optimized and tested using a real world database. We applied the Simplex algorithm to a representative subset of our database to find an improved set of filter parameters. Analysis led to two improved filters: one dedicated to benign clutter conditions and the other to cloud clutter-dominated scenes. In this paper, we demonstrate how a fused version of the two optimized filters further improves performance in severe cloud clutter scenes. The performance characteristics of the filters will be detailed by specific examples and plots. Real time operation has been demonstrated on laboratory IR cameras. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. RP Caefer, CE (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 0 TC 17 Z9 18 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 0-8194-2822-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3373 BP 111 EP 122 DI 10.1117/12.324612 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL66J UT WOS:000076232400013 ER PT S AU Layne, JR AF Layne, JR BE Drummond, OE TI Monopulse radar tracking using an adaptive interacting multiple model method with extended Kalman filters SO SIGNAL AND DATA PROCESSING OF SMALL TARGETS 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Signal and Data Processing of Small Targets CY APR 14-16, 1998 CL ORLANDO, FL SP SPIE DE tracking systems; adaptive systems; interacting multiple model tracking; IMM; monopulse radar; extended Kalman filter AB In this paper we investigate an adaptive interacting multiple model (AIMM) tracker using the extended Kalman filter. This adaptive algorithm is based on the interacting multiple model (IMM) tracking technique with the addition of an adaptive acceleration model to track behavior that falls in between the fixed model dynamics. In previous research, we found that the adaptive model matches more closely the hue system dynamics when the target kinematics lie in between the fixed models, thus improving the overall performance of the tracking system. We also showed that the AIMM outperforms other existing adaptive approaches while reducing computational complexity. In this paper, we further investigate these superior qualities of the AIMM by considering a more realistic radar-tracking scenario where monopulse radar range, azimuth, and elevation measurements are processed using extended Kalman filters in the AIMM. Here a more complex three-dimensional simulation is implemented instead of the simplified two dimensional problem considered in our previous research. Again, the results show that the AIMM outperforms the classical IMM when the target is maneuvering. C1 AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. RP Layne, JR (reprint author), AFRL, SNAT, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2822-1 J9 P SOC PHOTO-OPT INS PY 1998 VL 3373 BP 259 EP 270 DI 10.1117/12.324625 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL66J UT WOS:000076232400026 ER PT S AU Musick, S Kastella, K Mahler, R AF Musick, S Kastella, K Mahler, R BE Kadar, I TI A practical implementation of joint multitarget probabilities SO SIGNAL PROCESSING, SENSOR FUSION, AND TARGET RECOGNITION VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Signal Processing, Sensor Fusion, and Target Recognition VII CY APR 13-15, 1998 CL ORLANDO, FL SP SPIE DE detection; tracking; sensor management; multitarget probability; multisensor fusion; global density; probability approximation; random sets; nonlinear filtering; Bayesian filtering AB A Joint Multitarget Probability (JMP) is a posterior probability density p(T)(x(1),..., x(T) \ Z) that there are T targets (T an unknown number) with unknown locations specified by the multitarget state X = (x(1),..., x(T))(T) conditioned on a set of observations Z. This paper presents a numerical approximation for implementing JMP in detection, tracking and sensor management applications. A problem with direct implementation of JMP is that, if each x(1), t = 1,,..,T, is discretized on a grid of N elements, N-T variables are required to represent JMP on the T-target sector. This produces a large computational requirement even for small values of N and T. However, when the sensor easily separates targets, the resulting JMP factorizes and can be approximated by a product representation requiring only O((TN)-N-2) variables. Implementation of JMP for multitarget tracking requires a Bayes' rule step for measurement update and a Markov transition step for time update. If the measuring sensor is only influenced by the cell it observes, the JMP product representation is preserved under measurement update. However, the product form is not quite preserved by the Markov time update, but can be restored using a minimum discrimination approach. All steps for the approximation can be performed with O(N) effort. This notion is developed and demonstrated in numerical examples with at most two targets in a 1-dimensional surveillance region. In this case, numerical results for detection and tracking for the product approximation and the full JMP are very similar. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Musick, S (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 26 Z9 26 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 0-8194-2823-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3374 BP 26 EP 37 DI 10.1117/12.327111 PG 12 WC Engineering, Aerospace; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Optics SC Engineering; Computer Science; Optics GA BL57G UT WOS:000075913400003 ER PT S AU McIntyre, GA Hintz, KJ AF McIntyre, GA Hintz, KJ BE Kadar, I TI A comparison of several maneuvering target tracking models SO SIGNAL PROCESSING, SENSOR FUSION, AND TARGET RECOGNITION VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Signal Processing, Sensor Fusion, and Target Recognition VII CY APR 13-15, 1998 CL ORLANDO, FL SP SPIE DE tactically maneuvering targets; Kalman filters; target tracking; exponentially correlated acceleration models AB The tracking of maneuvering targets is complicated by the fact that acceleration is not directly observable or measurable. Additionally, acceleration can be induced by a variety of sources including human input, autonomous guidance, or atmospheric disturbances. The approaches to tracking maneuvering targets can be divided into two categories both of which assume that the maneuver input command is unknown. One approach is to model the maneuver as a random process. The other approach assumes that the maneuver is not random and that it is either detected or estimated in realtime. The random process models generally assume one of two statistical properties, either white noise or an autocorrelated noise. The multiple-model approach is generally used with the white noise model while a zero-mean, exponentially correlated acceleration approach is used with the autocorrelated noise model. The nonrandom approach uses maneuver detection to correct the state estimate or a variable dimension filter to augment the state estimate with an extra state component during a detected maneuver. Another issue with the tracking of maneuvering target is whether to perform the Kalman filter in Polar or Cartesian coordinates. This paper will examine and compare several exponentially correlated acceleration approaches in both Polar and Cartesian coordinates for accuracy and computational complexity. They include the Singer model in both Polar and Cartesian coordinates, the Singer model in Polar coordinates converted to Cartesian coordinates, Helferty's third order rational approximation of the Singer model and the Bar-Shalom and Fortmann model. This paper shows that these models all provide very accurate position estimates with only minor differences in velocity estimates and compares the computational complexity of the models. C1 USAF, Inst Technol, Dept Operat Sci, Washington, DC 20330 USA. RP McIntyre, GA (reprint author), USAF, Inst Technol, Dept Operat Sci, Washington, DC 20330 USA. NR 0 TC 7 Z9 8 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 0-8194-2823-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3374 BP 48 EP 63 DI 10.1117/12.327127 PG 16 WC Engineering, Aerospace; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic; Optics SC Engineering; Computer Science; Optics GA BL57G UT WOS:000075913400005 ER PT S AU Sanchez, EK Heydemann, VD Rohrer, GS Skowronski, M Solomon, J Capano, MA Mitchel, WC AF Sanchez, EK Heydemann, VD Rohrer, GS Skowronski, M Solomon, J Capano, MA Mitchel, WC BE Pensl, G Morkoc, H Monemar, B Janzen, E TI Structural characterization of SiC crystals grown by physical vapor transport SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE extended defects; silicon carbide; inclusions; dislocations ID DEFECTS AB Extended defects in silicon carbide crystals have been investigated by Nomarski-contrast optical microscopy, high resolution X-ray diffraction, X-ray topography, and Auger electron spectroscopy. Two types of inclusions have been observed and tentatively identified as carbon and silicon. Etching in molten KOH revealed dislocations intersecting the wafer surface. Three types of etch pits correspond to micropipes, threading dislocations (both screw and edge-type) extending along the [00.1] direction, and basal plane dislocations. Etch pits frequently formed well defined lines along <<1(1.)over bar 0>> directions. X-ray diffraction was used to determine that these dislocation arrays are low angle grain boundaries with typical misorientations of approximately 50 are. The misorientations were of mixed character, including both the twisting and tilting of grains along the c-axis. C1 Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. USAF, Wright Lab, MLPO, Wright Patterson AFB, OH 45433 USA. RP Sanchez, EK (reprint author), Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. RI Skowronski, Marek/A-8934-2011; Monemar, Bo/B-3718-2016; Rohrer, Gregory/A-9420-2008 OI Skowronski, Marek/0000-0002-2087-0068; Rohrer, Gregory/0000-0002-9671-3034 NR 9 TC 3 Z9 3 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 433 EP 436 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000102 ER PT S AU Mitchel, WC Perrin, R Goldstein, J Roth, M Ahoujja, M Smith, SR Evwaraye, AO Solomon, JS Landis, G Jenny, J Hobgood, HM Augustine, G Balakrishna, V AF Mitchel, WC Perrin, R Goldstein, J Roth, M Ahoujja, M Smith, SR Evwaraye, AO Solomon, JS Landis, G Jenny, J Hobgood, HM Augustine, G Balakrishna, V BE Pensl, G Morkoc, H Monemar, B Janzen, E TI Deep levels in SiC : V by high temperature transport measurements SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE vanadium doping; Hall effect; semi-insulating material ID ELECTRONIC-PROPERTIES; VAPOR TRANSPORT; VANADIUM; CARBIDE AB Vanadium doped 6H and 4H SiC have been studied with high temperature Hall effect and resistivity, optical absorption and SIMS. The 6H samples were found to exhibit three thermal activation energies, 0.35 eV, 0.7 eV and near mid-gap. The 0.3 eV level is due to thermal ionization of residual uncompensated boron. We attribute the mid-gap level to thermal ionization of the vanadium donor level. The 0.7 eV activation is believed to be due to transfer of electrons from the ionized vanadium acceptor levels to the conduction band. These results suggest that the vanadium donor and acceptor levels are located at E-c - 1.42 eV and E-V + 2.4 eV respectively. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Dayton, OH 45469 USA. Northrop Grumman Corp, Ctr Sci & Technol, Pittsburgh, PA 15235 USA. RP Mitchel, WC (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RI Monemar, Bo/B-3718-2016 NR 7 TC 13 Z9 13 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 545 EP 548 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000129 ER PT S AU Scott, MB Scofield, JD Yeo, YK Hengehold, RL AF Scott, MB Scofield, JD Yeo, YK Hengehold, RL BE Pensl, G Morkoc, H Monemar, B Janzen, E TI Deep level defect study of ion implanted (Ar, Mg, Cr) n-type 6H-SiC by deep level transient spectroscopy SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE DLTS; ion implantation; defect levels; complexes; annealing; SiC ID ELECTRON-SPIN-RESONANCE AB Deep level transient spectroscopy (DLTS) over a temperature range of 100 to 650 K was performed on n-type 6H-SiC implanted with Ar, Cr and Mg ions. Species-related and damage-related majority carrier defect levels were observed with energies ranging from 240 to 615 meV. Observed implanted ion dose, implantation temperature, anneal temperature, and doping concentration effects indicate possible trap evolution and identification. 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. RI Monemar, Bo/B-3718-2016 NR 11 TC 1 Z9 1 U1 0 U2 1 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 549 EP 552 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000130 ER PT S AU Smith, SR Evwaraye, AO Mitchel, WC AF Smith, SR Evwaraye, AO Mitchel, WC BE Pensl, G Morkoc, H Monemar, B Janzen, E TI Phonon spectrum of band-to-band optical transitions in 6H-SiC as determined by Optical Admittance Spectroscopy SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE admittance spectroscopy; phonons; interband transitions ID PRESSURE-DEPENDENCE AB Peaks in Optical admittance spectra have been determined to be related to the absorption and emission of phonons in interband transitions. These peaks are seen when the wavelength is scanned from 300 nm to 500 nm. The strongest transition is seen for the transverse acoustic phonon absorption assisted transition to the second conduction band minimum. A second peak is seen for transverse acoustic phonon emission to the first conduction band minimum. The temperature dependence of the transitions was also measured. Though little or no temperature dependence was seen in the phonon energies a maximum was seen in the area of some phonon peaks below 100 K. C1 MLPO, WL, Wright Lab, Mat Directorate, 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), MLPO, WL, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RI Monemar, Bo/B-3718-2016 NR 9 TC 1 Z9 1 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 569 EP 572 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000135 ER PT S AU Liu, S Scofield, JD AF Liu, S Scofield, JD BE Pensl, G Morkoc, H Monemar, B Janzen, E TI Ohmic contacts to p-type SiC with improved thermal stability SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE ohmic contact; contact resistivity; thermal stability AB Ohmic contacts to p-type 4H- and 6H-SiC have been obtained using Ni, Ni/W, Al/Ni, and Al/Ni/W metallization systems after annealing at 850 - 1050 degrees C for 2 - 5 minutes. Post-anneal X-ray diffraction analysis of the Al/Ni contact revealed the formation of a binary AlNi compound. Chemical depth profiles, obtained by Auger electron spectroscopy, showed that part of Al diffused to the surface through the Ni overlayer and formed Al2O3 during annealing. Adding a refractory W cap layer and lowering the annealing temperature effectively prevented Al oxide formation. The lowest contact resistivity of 4x10(-5) ohm-cm was obtained in the Al/Ni/W system. The new Ni/W and Al/Ni/W ohmic contacts illustrated excellent thermal stability, The contact resistivity and I-V characteristics remain unchanged after aging at 400 degrees C for 1098 hours. C1 Univ Dayton, Dayton, OH 45469 USA. USAF, Wright Lab, Wright Patterson AFB, OH 45433 USA. RP Liu, S (reprint author), Univ Dayton, Dayton, OH 45469 USA. RI Monemar, Bo/B-3718-2016 NR 4 TC 8 Z9 8 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 791 EP 794 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000188 ER PT S AU Spitz, J Melloch, MR Cooper, JA Capano, MA AF Spitz, J Melloch, MR Cooper, JA Capano, MA BE Pensl, G Morkoc, H Monemar, B Janzen, E TI High-voltage (2.6kV) lateral DMOSFETs in 4H-SiC SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE DMOS; LDMOS; power MOSFETs; semiconductor on insulator; SOI; RESURF AB We report the first lateral double-implanted power MOSFET (LDMOS) in silicon carbide. By allowing the n- drift region to extend laterally over an insulating SiC substrate, we achieve blocking voltages of 2.6 kV at 23 degrees C and 2.2 kV at 155 degrees C. C1 Purdue Univ, Sch Elect & Comp Engn, W Lafayette, IN 47907 USA. USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Spitz, J (reprint author), Purdue Univ, Sch Elect & Comp Engn, W Lafayette, IN 47907 USA. RI Monemar, Bo/B-3718-2016 NR 6 TC 8 Z9 8 U1 0 U2 0 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 1005 EP 1008 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000239 ER PT S AU Jarrendahl, K Smith, SA Zheleva, T Kern, RS Davis, RF AF Jarrendahl, K Smith, SA Zheleva, T Kern, RS Davis, RF BE Pensl, G Morkoc, H Monemar, B Janzen, E TI Growth of AlN on 6H- and 4H-SiC by gas-source molecular beam epitaxy SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE gas-source molecular beam epitaxy; ammonia; thin films; surface reconstruction ID ALUMINUM NITRIDE; DEFECT FORMATION; SILICON-CARBIDE AB Highly (0001)-oriented aluminum nitride (AlN) thin films with very smooth surfaces have been grown by gas-source molecular beam epitaxy (GSMBE) on 6H- and 4H-SiC substrates. High purity ammonia was used as the nitrogen source in conjunction with Al evaporated from an effusion cell. Streaked reflection high energy electron diffraction (RHEED) patterns and reconstructions of the AlN surfaces indicated smooth films. This surface character was confirmed via atomic force microscopy (AFM) and transmission electron microscopy (TEM) which showed root mean square (RMS) values typically below 10 Angstrom and very flat surfaces, respectively. X-ray diffraction (XRD) showed the films to be highly oriented and single phase. The major impurity was oxygen, as revealed by secondary ion mass spectrometry (SIMS). C1 N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Jarrendahl, K (reprint author), N Carolina State Univ, Dept Mat Sci & Engn, Box 7907, Raleigh, NC 27695 USA. RI Davis, Robert/A-9376-2011; Jarrendahl, Kenneth/E-1807-2014; Monemar, Bo/B-3718-2016 OI Davis, Robert/0000-0002-4437-0885; Jarrendahl, Kenneth/0000-0003-2749-8008; NR 12 TC 4 Z9 4 U1 0 U2 3 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 1181 EP 1184 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000281 ER PT S AU Xu, G Salvador, A Botchkarev, AE Kim, W Lu, C Tang, H Morkoc, H Smith, G Estes, M Dang, T Wolf, P AF Xu, G Salvador, A Botchkarev, AE Kim, W Lu, C Tang, H Morkoc, H Smith, G Estes, M Dang, T Wolf, P BE Pensl, G Morkoc, H Monemar, B Janzen, E TI High speed, low noise ultraviolet photodetectors based on GaN p-i-n and AlGaN(p)-GaN(i)-GaN(n) structures SO SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2 SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 7th International Conference on Silicon Carbide, III-Nitrides and Related Materials (ICSCIII-N 97) CY AUG 31-SEP 05, 1997 CL STOCKHOLM, SWEDEN SP Linkoping Univ, ABB Asea Brown Boveri Ltd, Cree Res Ltd, Okmetik OY, Epigress AB, Swedish Res Council Engn Sci, Swedish Nat Sci Res Council, Ericsson Components AB, Thomson CSF, Siemens AG, Daimler Benz AG, City Stockholm, Stockholm Cty Council DE photodetectors; reactive molecular beam epitaxy AB We have investigated the spectral response of front surface illuminated GaN, AlGaN /GaN and AlGaN p-i-n ultraviolet photodetectors grown by reactive molecular beam epitaxy on sapphire substrates. The GaN homojunction p-i-n photodiode exhibited a peaked response at 364 nm the origin of which is not yet clear. This response was absent in the AlGaN /GaN heterojunction p-i-n detectors. The maximum responsivity for the unbiased GaN and AlGaN /GaN is 0.07 and 0.12 A/W, respectively, and occurs at 364 nm. The responsivity drops by more than 3 orders of magnitude near 390 nm. The AlGaN homojunction p-i-n on the other hand has a peak responsivity of 0.08 A/W at 340 nm. The noise equivalent power of 4 pW and 8.3 pW were obtained for the GaN and AlGaN/GaN photodiodes respectively. We measured extremely fast decay times of 12 ns for the AlGaN /GaN and 29 ns for the GaN photodiodes. C1 Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Univ Illinois, Coordinated Sci Lab, Urbana, IL 61801 USA. USAF, Wright Lab, Wright Patterson AFB, OH 45433 USA. Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Xu, G (reprint author), Univ Illinois, Mat Res Lab, 1101 W Springfield Ave, Urbana, IL 61801 USA. RI Monemar, Bo/B-3718-2016 NR 5 TC 2 Z9 2 U1 2 U2 3 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-790-0 J9 MATER SCI FORUM PY 1998 VL 264-2 BP 1441 EP 1444 PN 1-2 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BK61S UT WOS:000072751000343 ER PT S AU Denoyer, KK Griffin, SF Sciulli, D AF Denoyer, KK Griffin, SF Sciulli, D BE Regelbrugge, ME TI Hybrid structural/acoustic control of a sub-scale payload fairing SO SMART STRUCTURES AND MATERIALS 1998: SMART STRUCTURES AND INTEGRATED SYSTEMS, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Smart Structures and Integrated Systems CY MAR 02-05, 1998 CL SAN DIEGO, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp DE structural control; acoustic control; vibration suppression; positive position feedback AB During launch, spacecraft experience severe acoustic and vibration loads. Acoustic loads are primarily transmitted through the shroud or payload fairing of the launch vehicle. In recent years, there has been a trend towards using lighter weight and extremely stiff structures such as sandwich construction and grid-stiffened composites in the manufacturing of payload fairings. While substantial weight savings can be achieved using these materials, the problem of acoustic transmission is exacerbated. For this reason, the Air Force Research Laboratory has been actively engaged in vibroacoustic research aimed at reducing the acoustic and vibration levels seen by payloads during launch. This paper presents experimental results for the simultaneous structural and acoustic cavity mode control of a sub-scale composite isogrid payload fairing structure. In this experiment, actuation is performed through the use of both an internal speaker as well as piezoceramic strain actuators located on the outer skin of the composite structure. Sensing is accomplished using a microphone as well as a piezoelectric strain sensor. The control approach presented in this paper is a decentralized frequency domain approach which makes use of a series of independent control loops. One loop uses the microphone and speaker, while additional loops use the piezoelectric sensors and actuators. The control algorithm consists of independent second-order Positive Position Feedback (PPF) controllers tuned to reduce the magnitude of each cavity mode. A PPF filter in conjunction with an extremely sharp bandpass filter is used on the structural mode to limit spillover. This approach leads to a substantial reduction in the acoustic transmission in the range of 0-800 Hz. Transmission coincident with the primary cavity modes of the system are reduced in magnitude by 26 and 9dB respectively while the structural mode that is responsible for the majority of transmission is reduced by approximately 7 dB. C1 USAF, Res Lab, AFRL, VSDV, Kirtland AFB, NM 87117 USA. RP Denoyer, KK (reprint author), USAF, Res Lab, AFRL, VSDV, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 4 Z9 4 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 0-8194-2773-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3329 BP 237 EP 243 DI 10.1117/12.316896 PN 1-2 PG 7 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Optics SC Acoustics; Engineering; Optics GA BL52W UT WOS:000075786600022 ER PT S AU Matre, JS Wahrmund, JC Waters, DP AF Matre, JS Wahrmund, JC Waters, DP BE Regelbrugge, ME TI Comparative analysis of smart bearing sensors SO SMART STRUCTURES AND MATERIALS 1998: SMART STRUCTURES AND INTEGRATED SYSTEMS, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Smart Structures and Integrated Systems CY MAR 02-05, 1998 CL SAN DIEGO, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp DE health monitoring; vibrations; rolling element bearing; transducers; embedded sensor; helicopter life extension; rotating shafts AB Currently, the Air Force's fleet of aircraft, and helicopters in particular, are aging. These aircraft are nearing the end of their design life, but are being required to continue service well into the next century. In an attempt to help extend the life of these aircraft, the area of health monitoring has received considerable interest. In the case of the MH-53J PAVE LOW, this health monitoring has taken the form of vibration monitoring. The initial effort at health monitoring has consisted of placing accelerometers on the bearing support brackets for the tail rotor drive shaft. The results of this monitoring have provided information that allows the maintainers to replace the bearings only when the bearing is showing signs of wear rather than at a given interval. Additionally, the data has been used to make near real time evaluations of the airworthiness of the aircraft. The result has been a decrease of 50% in the number of missions canceled due to vibration related issues. The Air Force is looking at expanding the present vibration monitoring system to the entire fleet of MH-53J aircraft. In conjunction with this expansion, this paper looks at evaluating a transducer specifically designed for monitoring bearings. A comparison between accelerometer responses and the bearing transducer response is made. C1 USAF Acad, Dept Engn Mech, Colorado Springs, CO 80840 USA. RP Waters, DP (reprint author), USAF Acad, Dept Engn Mech, 2354 Fairchild Dr,Suite 6H2, 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 0-8194-2773-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3329 BP 500 EP 510 DI 10.1117/12.316920 PN 1-2 PG 11 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Optics SC Acoustics; Engineering; Optics GA BL52W UT WOS:000075786600043 ER PT S AU Griffin, SF Denoyer, KK AF Griffin, SF Denoyer, KK BE Regelbrugge, ME TI Experimental sensor and actuator location procedure for control of dynamically complex smart structures SO SMART STRUCTURES AND MATERIALS 1998: SMART STRUCTURES AND INTEGRATED SYSTEMS, PTS 1 AND 2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT SPIE Conference on Smart Structures and Integrated Systems CY MAR 02-05, 1998 CL SAN DIEGO, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp DE smart structures; sensors and actuators; structural control; acoustic control; piezoelectrics AB In choosing positions for sensors and actuators for structural control, the first step is usually to develop a model that describes the motion of the structure in response to an excitation. The next step depends on the type of sensors and actuators used. If displacement or acceleration sensors and shakers are used, the model serves as a guide to find locations on the structure where displacement is large for a given disturbance. If in-plane strain-based smart sensors and actuators are used, the model is used to identify locations with large in-plane strain. If the structure is relatively complex, there is a good chance that the initial model will not predict motion that agrees completely with the measured motion of the structure. This initial model is then typically adjusted so that the behavior it predicts agrees with a measured modal analysis of the structure. This process can be extremely time consuming, and while the reconciled modes often agree well with a modal analysis, there can be large errors with respect to in-plane strain. Prediction of in-plane is necessary for accurate location of smart sensors and actuators like piezoceramics. In this paper an experimental method is introduced which uses in-plane sensors to find good smart sensor and actuator locations to control acoustic excitation of a complex structure. Experimental results are also presented which demonstrate the proposed technique. C1 USAF, Res Lab, VSDV, Kirtland AFB, NM 87117 USA. RP Griffin, SF (reprint author), USAF, Res Lab, VSDV, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 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 0-8194-2773-X J9 P SOC PHOTO-OPT INS PY 1998 VL 3329 BP 717 EP 723 DI 10.1117/12.316936 PN 1-2 PG 7 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Optics SC Acoustics; Engineering; Optics GA BL52W UT WOS:000075786600062 ER PT S AU Knipp, DJ Emery, BA AF Knipp, DJ Emery, BA BE Strangeway, RJ TI A report on the community study of the early November 1993 geomagnetic storm SO SOLAR-TERRESTRIAL RELATIONS: PREDICTING THE EFFECTS ON THE NEAR- EARTH ENVIRONMENT SE ADVANCES IN SPACE RESEARCH LA English DT Article; Proceedings Paper CT DO 7 Symposium of COSPAR Scientific-Commission-D on Solar-Terrestrial Relations - Predicting the Effects on the Near-Earth Environment at the 31st COSPAR Sci Assembly CY JUL 14-21, 1996 CL BIRMINGHAM, ENGLAND SP Comm Space Res, Sci Commiss C AB In anticipation of the upcoming solar maximum a large segment of the solar-terrestrial community has joined in an effort to document and benchmark the strengths and shortcomings of the community's observational and modeling capabilities. Approximately 100 scientists are participating in a study of a significant solar-terrestrial event which influenced the Earth between 2 and 11 November 1993. The goal of the study is to follow the event from its origin at the Sun, tracing the flow of particles and energy through the interplanetary medium and into the dissipative elements of the magnetosphere, ionosphere and thermosphere, thus providing a test-bed for existing space weather analysis and modeling capabilities. The geomagnetic storm of early November 1993 was identified as a candidate for study. While the study was inspired by the US National Space Weather program, it has become an international event study. The following paper provides information about the origin and significance of the storm, the reasons for its selection as a community study event and a brief status report of the study. C1 USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. RP Knipp, DJ (reprint author), USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. NR 40 TC 2 Z9 2 U1 1 U2 2 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 BN 0-08-043465-7 J9 ADV SPACE RES PY 1998 VL 22 IS 1 BP 41 EP 54 DI 10.1016/S0273-1177(97)01098-3 PG 14 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BL44W UT WOS:000075554000004 ER PT S AU Richmond, AD Lu, G Emery, BA Knipp, DJ AF Richmond, AD Lu, G Emery, BA Knipp, DJ BE Strangeway, RJ TI The AMIE procedure: Prospects for space weather specification and prediction SO SOLAR-TERRESTRIAL RELATIONS: PREDICTING THE EFFECTS ON THE NEAR- EARTH ENVIRONMENT SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT DO 7 Symposium of COSPAR Scientific-Commission-D on Solar-Terrestrial Relations - Predicting the Effects on the Near-Earth Environment at the 31st COSPAR Sci Assembly CY JUL 14-21, 1996 CL BIRMINGHAM, ENGLAND SP Comm Space Res, Sci Commiss C ID IONOSPHERIC CONVECTION RESPONSE; MAPPING ELECTRODYNAMIC FEATURES; INTERPLANETARY MAGNETIC-FIELD; POSTMIDNIGHT DIFFUSE AURORA; INCOHERENT-SCATTER RADAR; HIGH-LATITUDE IONOSPHERE; REGION NEUTRAL WINDS; LOCALIZED OBSERVATIONS; ATMOSPHERIC RESPONSE; ALIGNED CURRENT AB The Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure synthesizes diverse observations of high-latitude ionospheric electrodynamic phenomena into "snapshot" synoptic maps of conductances, electric fields, currents, and related parameters. It makes use of available statistical information concerning average patterns, standard deviations, and correlation distances of the various parameters. The algorithm incorporates a number of features that would facilitate operational use, including its automatic checking for outliers to help identify bad data, its ability to function even when data are sparse or missing, and its estimation of the uncertainties in its mapped outputs. At present, AMIE is a specification model rather than a forecast model, although its mathematical structure could allow inclusion of time as an additional dimension, which would permit temporal extrapolation. Nonetheless, a specification model of convection and particle precipitation can be used to help initialize forecast models of thermospheric winds and composition, ionospheric electron density, and inner-magnetospheric particle populations. (C) 1998 COSPAR. Published by Elsevier Science Ltd. All rights reserved. C1 Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. RP Richmond, AD (reprint author), Natl Ctr Atmospher Res, High Altitude Observ, Pob 3000, Boulder, CO 80307 USA. RI Lu, Gang/A-6669-2011; OI Richmond, Arthur/0000-0002-6708-1023 NR 30 TC 14 Z9 14 U1 1 U2 2 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 BN 0-08-043465-7 J9 ADV SPACE RES-SERIES PY 1998 VL 22 IS 1 BP 103 EP 112 DI 10.1016/S0273-1177(97)01108-3 PG 10 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BL44W UT WOS:000075554000014 ER PT B AU Fosness, ER Madison, R Founds, DB AF Fosness, ER Madison, R Founds, DB BE Galloway, RG Lokaj, S TI Advanced spacecraft mechanisms work at the USAF research laboratory SO SPACE 98 LA English DT Proceedings Paper CT 6th International Conference and Exposition on Engineering, Construction, and Operations in Space (Space 98) CY APR 26-30, 1998 CL ALBUQUERQUE, NM SP Amer Soc Civil Engineers, Aerospace Div, Sandia Natl Labs, Amer Astronaut Soc, Amer Inst Architects, NASA, Kirtland Air Force Base, Phillips Site, Air Force Res Lab, New Mexico, Wright Patterson Air Force Base, Wright Patterson Site, Ohio, Air Force Acad. Colorado Springs, Bechtel Corp, Fluor Daniel Inc AB Spacecraft require a variety of mechanisms to accomplish mission related functions such as deployment, articulation, and positioning of spacecraft structures and instruments. Suitable devices, using proven technologies, are available off-the-shelf. However, increasingly stringent weight, power, accuracy and other requirements for future satellites will exceed the capability of devices built with current technologies. This paper summarizes several innovative technologies that the Air Force Research Laboratory is researching to produce more efficient and accurate spacecraft mechanisms. These technologies include shape memory actuators, lightweight solar arrays, precision gimbals, magnetic bearings and robotics. Several mechanisms developed in these programs are scheduled for space flight demonstrations in 1998, 1999 and 2001. C1 USAF, Res Lab, Albuquerque, NM 87117 USA. RP Fosness, ER (reprint author), USAF, Res Lab, Albuquerque, NM 87117 USA. NR 5 TC 0 Z9 0 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 0-7844-0339-2 PY 1998 BP 58 EP 65 PG 8 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BM53L UT WOS:000079075300008 ER PT B AU Khot, NS Bhungalia, AA AF Khot, NS Bhungalia, AA BE Galloway, RG Lokaj, S TI Multiobjective design of structures with bounded control for vibration suppression SO SPACE 98 LA English DT Proceedings Paper CT 6th International Conference and Exposition on Engineering, Construction, and Operations in Space (Space 98) CY APR 26-30, 1998 CL ALBUQUERQUE, NM SP Amer Soc Civil Engineers, Aerospace Div, Sandia Natl Labs, Amer Astronaut Soc, Amer Inst Architects, NASA, Kirtland Air Force Base, Phillips Site, Air Force Res Lab, New Mexico, Wright Patterson Air Force Base, Wright Patterson Site, Ohio, Air Force Acad. Colorado Springs, Bechtel Corp, Fluor Daniel Inc AB This paper describes a method to design a structure and control system simultaneously using multiobjective optimization method based on using the Euclidean norm. In the design of the control system, the state space equations are integrated using a Runge-Kutta method for specified initial boundary condition and the constraints on maximum values of the control forces. The structural weight and weight of the actuators, are considered as the criteria functions. The design variables are the control bounds, the cross-sectional areas of the structural elements and elements of the weighting matrices. As an example to illustrate the application of an approach, a box beam idealized by rod elements is used. C1 USAF, Res Lab, Air Vehicles Directorate, Struct Div, Wright Patterson AFB, OH 45433 USA. RP Khot, NS (reprint author), USAF, Res Lab, Air Vehicles Directorate, Struct Div, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 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 0-7844-0339-2 PY 1998 BP 79 EP 85 PG 7 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BM53L UT WOS:000079075300011 ER PT B AU Sciulli, D Fosness, E Das, A AF Sciulli, D Fosness, E Das, A BE Galloway, RG Lokaj, S TI Soft ride for satellites SO SPACE 98 LA English DT Proceedings Paper CT 6th International Conference and Exposition on Engineering, Construction, and Operations in Space (Space 98) CY APR 26-30, 1998 CL ALBUQUERQUE, NM SP Amer Soc Civil Engineers, Aerospace Div, Sandia Natl Labs, Amer Astronaut Soc, Amer Inst Architects, NASA, Kirtland Air Force Base, Phillips Site, Air Force Res Lab, New Mexico, Wright Patterson Air Force Base, Wright Patterson Site, Ohio, Air Force Acad. Colorado Springs, Bechtel Corp, Fluor Daniel Inc AB Today, a satellite has to be designed to survive its launch environment since this is the worst-case loading condition for the satellite, This results in an over design of the satellite structure; thereby, adding extra weight to the satellite structure that could be used for additional science/commercial purposes. The USAF Research Laboratory is actively investigating an approach to minimize launch loads to satellites in the form of a whole-spacecraft launch isolator. The objective of the current effort is to reduce the launch-induced structural-borne dynamic acceleration of the satellite by insertion of an isolation system that provides the satellite a softer ride to space. This paper discusses several efforts being analyzed and managed by the USAF Research Laboratory in the area of whole-spacecraft launch isolation. These programs are targeted for small to medium class launch vehicles, but the technology is applicable to all sizes of launch vehicles. This paper presents the work performed from several of these programs, and discusses the near term Eight opportunities for the Air Force Research Laboratory's whole-spacecraft isolation systems. C1 USAF, Res Lab, AFRL, VSDV, Kirtland AFB, NM 87117 USA. RP Sciulli, D (reprint author), USAF, Res Lab, AFRL, VSDV, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 3 TC 0 Z9 0 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 0-7844-0339-2 PY 1998 BP 94 EP 101 PG 8 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BM53L UT WOS:000079075300013 ER PT B AU Miller, GB Davis, RJ AF Miller, GB Davis, RJ BE Galloway, RG Lokaj, S TI MightySat II: Rapid access to space for the Air Force Research Laboratory SO SPACE 98 LA English DT Proceedings Paper CT 6th International Conference and Exposition on Engineering, Construction, and Operations in Space (Space 98) CY APR 26-30, 1998 CL ALBUQUERQUE, NM SP Amer Soc Civil Engineers, Aerospace Div, Sandia Natl Labs, Amer Astronaut Soc, Amer Inst Architects, NASA, Kirtland Air Force Base, Phillips Site, Air Force Res Lab, New Mexico, Wright Patterson Air Force Base, Wright Patterson Site, Ohio, Air Force Acad. Colorado Springs, Bechtel Corp, Fluor Daniel Inc AB MightySat is a United States Air Force (USAF) multi-mission, small satellite program dedicated to providing rapid, frequent, on-orbit demonstrations of high-payoff space system technologies. The Air Force Research Laboratory (AFRL) is the USAF center for space technology research & development. MightySat platforms provide the on-orbit "lab bench" for responsively testing emerging technologies to ensure their readiness for operational Air Force missions. This paper focuses on the MightySat II series of vehicles being developed largely by Spectrum Astro, Inc. in Gilbert, AZ. MightySat II Flight 1 ("Sindri"), a 275 lb. satellite designed for deployment from either the Orbital/Suborbital Program (OSP) or the Space Transportation System (STS), is now in final design stages, with Critical Design Review completed November 1997. Details of the current spacecraft bus design and upcoming integration and testing (I&T) plans are discussed. The development and integration of the advanced technology payloads for Sindri, namely the (I) Fourier Transform Hyperspectral Imager (FTHSI), (2) Advanced Thruster, (3) Plume Diagnostic Experiment (PDE), (4) Quad-C40 processor (QC40), (5) Solar Array Concentrator (SAC), (6) Shaped Memory Allow Thermoplastic Tailoring Experiment (SMATTE), (7) Solar Array Flex Interconnect (SAFI), and (8) advanced composite bus structure are described. A brief summary of future MightySat II vehicles and missions (Flights 2 through 5) is also provided. C1 USAF, Res Lab, AFRL, VSDD, Kirtland AFB, NM 87117 USA. RP Miller, GB (reprint author), USAF, Res Lab, AFRL, VSDD, Kirtland AFB, NM 87117 USA. NR 2 TC 0 Z9 0 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 0-7844-0339-2 PY 1998 BP 182 EP 196 PG 15 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BM53L UT WOS:000079075300022 ER PT B AU Snead, JM Hammond, WE AF Snead, JM Hammond, WE BE Galloway, RG Lokaj, S TI Air force, NASA and commercial cooperation in establishing a robust space infrastructure SO SPACE 98 LA English DT Proceedings Paper CT 6th International Conference and Exposition on Engineering, Construction, and Operations in Space (Space 98) CY APR 26-30, 1998 CL ALBUQUERQUE, NM SP Amer Soc Civil Engineers, Aerospace Div, Sandia Natl Labs, Amer Astronaut Soc, Amer Inst Architects, NASA, Kirtland Air Force Base, Phillips Site, Air Force Res Lab, New Mexico, Wright Patterson Air Force Base, Wright Patterson Site, Ohio, Air Force Acad. Colorado Springs, Bechtel Corp, Fluor Daniel Inc AB The United States has the technological capability to establish a robust space transportation, habitation and logistical support infrastructure in the first decade of the new century. This infrastructure will benefit all three sectors of the U.S. space program-commercial, civil and national defense-by providing shared capabilities that will improve the safety, reliability and affordability of all three sectors' primary space operations. This paper proposes specific technical approaches for establishing such an integrated infrastructure. The proposed infrastructure includes: reusable launch vehicles (RLV) for "airline-like" access to low Earth orbit (LEO); large spaceports in LEO capable of providing safe habitation for 100-150 people; and an integrated network of logistical support capabilities utilizing these RLVs and spaceports. The need for integrated planning to define and develop this common infrastructure is discussed. C1 USAF, Res Lab, XPZ, Wright Patterson AFB, OH 45433 USA. RP Snead, JM (reprint author), USAF, Res Lab, XPZ, Wright Patterson AFB, OH 45433 USA. NR 4 TC 0 Z9 0 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 0-7844-0339-2 PY 1998 BP 693 EP 701 PG 9 WC Engineering, Aerospace; Engineering, Civil SC Engineering GA BM53L UT WOS:000079075300079 ER PT S AU Giuliano, C Annaballi, AL AF Giuliano, C Annaballi, AL BE ElGenk, MS TI Lasers and space optical systems study SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1998, PTS 1-3: 1ST CONF ON GLOBAL VIRTUAL PRESENCE; 1ST CONF ON ORBITAL TRANSFER VEHICLES; 2ND CONF ON APPLICAT OF THERMOPHYS IN MICROGRAV; 3RD CONF ON COMMERCIAL DEV OF SPACE; 3RD CONF ON NEXT GENERAT LAUNCH SYST; 15TH SYMP ON SPACE NUCL POWER AND PROPULSION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1998 Space Technology and Applications International Forum (STAIF-98) - Progress in Expanding the Space Frontier CY JAN, 1998 CL ALBUQUERQUE, NM SP USAF, NASA, New Mexico Space Grant Consortium, Amer Nucl Soc, Trinity Sect, Univ New Mexico, Inst Space & Nucl Power Studies AB The Air Force and other government organizations have considered the application of space-based lasers since the early 1970s. Recent studies have identified the enormous potential of lasers and optical systems in space to support the full-Spectrum Dominance envisioned by the Joint Chiefs of Staff in "Joint Vision 2010." The Air Force Research Laboratory has undertaken the <(LA)under bar>sers and (S) under bar pace (O) under bar ptical (S) under bar ystems (LASSOS) Study to examine in detail how space lasers and optics (defined as any laser system based in space or any terrestrial-based laser whose beam transits space) could best be used to satisfy this critical need. This twelve-month study will identify promising technology concepts for space laser/optic systems, develop system concepts based on these technologies with special emphasis on systems capable of performing multiple missions, assess how well these systems can accomplish operational tasks in a quantitative manner, and design technology development roadmaps for selected concepts. Since work on the study had commenced only days before the publication deadline, this manuscript is necessarily limited to a description of the background, motivation, and organization of the study. The "Concept Definition" phase of the study is scheduled to be completed by the time of the STAIF conference. By that time, study participants will have identified key concepts that best satisfy criteria for timely and cost-effective augmentation of combat capability. A final report, which will be made available to authorized recipients, will be written after completion of the study in August 1998. C1 USAF, Phillips Lab, Res Lab, Kirtland AFB, NM 87117 USA. RP Giuliano, C (reprint author), USAF, Phillips Lab, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-747-2 J9 AIP CONF PROC PY 1998 IS 420 BP 80 EP 84 PG 5 WC Engineering, Aerospace; Remote Sensing; Physics, Applied SC Engineering; Remote Sensing; Physics GA BK50G UT WOS:000072374200013 ER PT S AU Muller, C Denman, C Gregg, M DeHainaut, L AF Muller, C Denman, C Gregg, M DeHainaut, L BE ElGenk, MS TI High-efficiency laser development for space applications SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1998, PTS 1-3: 1ST CONF ON GLOBAL VIRTUAL PRESENCE; 1ST CONF ON ORBITAL TRANSFER VEHICLES; 2ND CONF ON APPLICAT OF THERMOPHYS IN MICROGRAV; 3RD CONF ON COMMERCIAL DEV OF SPACE; 3RD CONF ON NEXT GENERAT LAUNCH SYST; 15TH SYMP ON SPACE NUCL POWER AND PROPULSION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1998 Space Technology and Applications International Forum (STAIF-98) - Progress in Expanding the Space Frontier CY JAN, 1998 CL ALBUQUERQUE, NM SP USAF, NASA, New Mexico Space Grant Consortium, Amer Nucl Soc, Trinity Sect, Univ New Mexico, Inst Space & Nucl Power Studies AB High-efficiency lasers are critical to space-based systems where power consumption severely constrains systems. This paper will review Air Force Research Laboratory/Phillips Laboratory (AFRL/PL) laser development programs which provide high-efficiency electric lasers for space-based communications and solid-state lasers for space-based clocks. C1 USAF, Res Lab, Laser Syst Div, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Muller, C (reprint author), USAF, Res Lab, Laser Syst Div, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-747-2 J9 AIP CONF PROC PY 1998 IS 420 BP 91 EP 94 PG 4 WC Engineering, Aerospace; Remote Sensing; Physics, Applied SC Engineering; Remote Sensing; Physics GA BK50G UT WOS:000072374200015 ER PT S AU Keener, D Reinhardt, K Mayberry, C Radzykewycz, D Donet, C Marvin, D Hill, C AF Keener, D Reinhardt, K Mayberry, C Radzykewycz, D Donet, C Marvin, D Hill, C BE ElGenk, MS TI Directions in US Air Force space power technology for global virtual presence SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1998, PTS 1-3: 1ST CONF ON GLOBAL VIRTUAL PRESENCE; 1ST CONF ON ORBITAL TRANSFER VEHICLES; 2ND CONF ON APPLICAT OF THERMOPHYS IN MICROGRAV; 3RD CONF ON COMMERCIAL DEV OF SPACE; 3RD CONF ON NEXT GENERAT LAUNCH SYST; 15TH SYMP ON SPACE NUCL POWER AND PROPULSION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1998 Space Technology and Applications International Forum (STAIF-98) - Progress in Expanding the Space Frontier CY JAN, 1998 CL ALBUQUERQUE, NM SP USAF, NASA, New Mexico Space Grant Consortium, Amer Nucl Soc, Trinity Sect, Univ New Mexico, Inst Space & Nucl Power Studies AB Recent trends in the development of high efficiency, light-weight, compact, reliable and cost-effective space power technologies needed to support the development of next-generation military and commercial satellites will be discussed. Development of new light-weight and reduced volume electrical power system (EPS) technologies are required to enable the design of future "smallsats" with power requirements less than 1500W, to "monstersats" having projected power levels ranging from 10-50kW for commercial communication and military space based radar type satellites. In support of these projected requirements a complement of power generation, power management and distribution, and energy storage technologies are under development at the Air Force Research Laboratory's Space Vehicles Directorate. The technologies presented in this paper include high efficiency multijunction solar cells, alkali metal thermal electric converters (AMTEC), high-voltage (70-130V)/high-efficiency/high-density power management and distribution (PMAD) electronics, and high energy density electrochemical and mechanical energy storage systems (sodium sulfur, lithium-ion, and flywheels). Development issues and impacts of individual technologies will be discussed in context with global presence satellite mission requirements. C1 USAF, Res Lab, VSDV, Kirtland AFB, NM 87117 USA. RP Keener, D (reprint author), USAF, Res Lab, VSDV, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-747-2 J9 AIP CONF PROC PY 1998 IS 420 BP 211 EP 222 PG 12 WC Engineering, Aerospace; Remote Sensing; Physics, Applied SC Engineering; Remote Sensing; Physics GA BK50G UT WOS:000072374200034 ER PT S AU Stapleton, D Galati, T McDougall, F AF Stapleton, D Galati, T McDougall, F BE ElGenk, MS TI Atmospheric considerations for skipping spaceplane trajectories SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1998, PTS 1-3: 1ST CONF ON GLOBAL VIRTUAL PRESENCE; 1ST CONF ON ORBITAL TRANSFER VEHICLES; 2ND CONF ON APPLICAT OF THERMOPHYS IN MICROGRAV; 3RD CONF ON COMMERCIAL DEV OF SPACE; 3RD CONF ON NEXT GENERAT LAUNCH SYST; 15TH SYMP ON SPACE NUCL POWER AND PROPULSION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1998 Space Technology and Applications International Forum (STAIF-98) - Progress in Expanding the Space Frontier CY JAN, 1998 CL ALBUQUERQUE, NM SP USAF, NASA, New Mexico Space Grant Consortium, Amer Nucl Soc, Trinity Sect, Univ New Mexico, Inst Space & Nucl Power Studies AB A mission to release a payload to low polar earth orbit by a conceptual Reusable Aero Space Vehicle (RASV) is considered for Monte Carlo atmospheric conditions. Atmospheres are applied to a baseline trajectory in which, after payload release, the spaceplane circumnavigates the globe and returns to its launch site by a boost glide maneuver (i.e. by skipping off the atmosphere) and the payload employs a small attached booster to put a satellite into a final orbit. Around-the-world RASV trajectories are found to be feasible under many atmospheric conditions; however, trajectory characteristics are found to vary substantially with atmospheric variations when a given set of fixed flight controls are used. C1 USAF, Res Lab, Prop Sci & Adv Concepts Div, Applicat & Assessments Branch, Edwards AFB, CA 93524 USA. RP Stapleton, D (reprint author), USAF, Res Lab, Prop Sci & Adv Concepts Div, Applicat & Assessments Branch, 5 Pollux Dr, Edwards AFB, CA 93524 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-747-2 J9 AIP CONF PROC PY 1998 IS 420 BP 881 EP 886 PG 6 WC Engineering, Aerospace; Remote Sensing; Physics, Applied SC Engineering; Remote Sensing; Physics GA BK50G UT WOS:000072374200145 ER PT S AU Croop, HC Lowndes, HB Hahn, SE Barthel, CA AF Croop, HC Lowndes, HB Hahn, SE Barthel, CA BE ElGenk, MS TI Thermo-mechanical evaluation of carbon-carbon primary structure for SSTO vehicles SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1998, PTS 1-3: 1ST CONF ON GLOBAL VIRTUAL PRESENCE; 1ST CONF ON ORBITAL TRANSFER VEHICLES; 2ND CONF ON APPLICAT OF THERMOPHYS IN MICROGRAV; 3RD CONF ON COMMERCIAL DEV OF SPACE; 3RD CONF ON NEXT GENERAT LAUNCH SYST; 15TH SYMP ON SPACE NUCL POWER AND PROPULSION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1998 Space Technology and Applications International Forum (STAIF-98) - Progress in Expanding the Space Frontier CY JAN, 1998 CL ALBUQUERQUE, NM SP USAF, NASA, New Mexico Space Grant Consortium, Amer Nucl Soc, Trinity Sect, Univ New Mexico, Inst Space & Nucl Power Studies AB An advanced development program to demonstrate carbon-carbon composite structure for use as primary load carrying structure has entered the experimental validation phase. demonstration component features an advanced carbon-carbon design incorporating 3D woven graphite preforms, integral spars, oxidation inhibited matrix, chemical vapor deposited (CVD) oxidation protection coating, and ceramic matrix composite fasteners. The validation component represents the culmination of a four phase design and fabrication development effort. Extensive developmental testing was performed to verify material properties and integrity of basic design features before committing to fabrication of the full scale box. The wing box component is now being set up for testing in the Air Force Research Laboratory Structural Test Facility at Wright-Patterson Air Force Base, Ohio. developmental tests performed in support of the design and planned testing of the full scale box was the fabrication and test of a skin/spar trial subcomponent. The trial subcomponent incorporated critical features of the full scale wing box design. This paper discusses the results of the trial subcomponent test which served as a pathfinder for the upcoming full scale box test. C1 USAF, Res Lab, Air Vehicles Directorate, Struct Div, Wright Patterson AFB, OH 45433 USA. RP Croop, HC (reprint author), USAF, Res Lab, Air Vehicles Directorate, Struct Div, 2790 D St,Bldg 65, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-747-2 J9 AIP CONF PROC PY 1998 IS 420 BP 1020 EP 1025 PG 6 WC Engineering, Aerospace; Remote Sensing; Physics, Applied SC Engineering; Remote Sensing; Physics GA BK50G UT WOS:000072374200165 ER PT S AU Hauber, BK AF Hauber, BK BE ElGenk, MS TI Development of actively cooled panels for advanced propulsion systems SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1998, PTS 1-3: 1ST CONF ON GLOBAL VIRTUAL PRESENCE; 1ST CONF ON ORBITAL TRANSFER VEHICLES; 2ND CONF ON APPLICAT OF THERMOPHYS IN MICROGRAV; 3RD CONF ON COMMERCIAL DEV OF SPACE; 3RD CONF ON NEXT GENERAT LAUNCH SYST; 15TH SYMP ON SPACE NUCL POWER AND PROPULSION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1998 Space Technology and Applications International Forum (STAIF-98) - Progress in Expanding the Space Frontier CY JAN, 1998 CL ALBUQUERQUE, NM SP USAF, NASA, New Mexico Space Grant Consortium, Amer Nucl Soc, Trinity Sect, Univ New Mexico, Inst Space & Nucl Power Studies AB Development of actively cooled flowpath panels for the National Aero-Space Plane (NASP) propulsion system was a critical task in the development plan of the air vehicle system. This task encompassed development of design requirements and loads, and component design and testing. In the early 90's the effort focused on six cooled panel designs based in five different materials (NARloy-Z, Haynes 188, MoRe, IN909, C/C and C/SiC), each satisfying requirements in a different area of the propulsion flowpath. Eventually, three of these designs were fabricated and tested. For these tests, two primary facilities were used. The first was a radiant heating facility at Wright Patterson Air Force Base (WPAFB), and the second, a vitiated air heater at General Applied Science Laboratories (GASL) Inc. In these facilities, tests were run to validate thermal and mechanical models and to demonstrate coating durability and effectiveness. Additional tests to assess the damage tolerance of these designs were planned but never run. These tests ultimately exposed strengths and weaknesses in the designs and the analysis methods. C1 USAF, Res Labs, Wright Patterson AFB, OH 45433 USA. RP Hauber, BK (reprint author), USAF, Res Labs, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-747-2 J9 AIP CONF PROC PY 1998 IS 420 BP 1027 EP 1032 PG 6 WC Engineering, Aerospace; Remote Sensing; Physics, Applied SC Engineering; Remote Sensing; Physics GA BK50G UT WOS:000072374200166 ER PT S AU Kennedy, FG AF Kennedy, FG BE ElGenk, MS TI Championing programs within the Air Force SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1998, PTS 1-3: 1ST CONF ON GLOBAL VIRTUAL PRESENCE; 1ST CONF ON ORBITAL TRANSFER VEHICLES; 2ND CONF ON APPLICAT OF THERMOPHYS IN MICROGRAV; 3RD CONF ON COMMERCIAL DEV OF SPACE; 3RD CONF ON NEXT GENERAT LAUNCH SYST; 15TH SYMP ON SPACE NUCL POWER AND PROPULSION SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1998 Space Technology and Applications International Forum (STAIF-98) - Progress in Expanding the Space Frontier CY JAN, 1998 CL ALBUQUERQUE, NM SP USAF, NASA, New Mexico Space Grant Consortium, Amer Nucl Soc, Trinity Sect, Univ New Mexico, Inst Space & Nucl Power Studies AB Building advocacy for the development of radical new systems within the Air Force--or DoD--requires the developer to engage a number of stakeholders within the acquisition and requirements communities. This paper discusses some of the intricacies and hurdles that a manager faces while attempting to negotiate the often confusing and complex processes of the requirements definition and acquisition communities. The importance of building a broad-based, committed coalition cannot be underestimated. C1 USAF, Off Undersecretary Def Acquisit & Technol, Acquisit Program Integrat, Washington, DC 20330 USA. RP Kennedy, FG (reprint author), USAF, Off Undersecretary Def Acquisit & Technol, Acquisit Program Integrat, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-747-2 J9 AIP CONF PROC PY 1998 IS 420 BP 1185 EP 1188 PG 4 WC Engineering, Aerospace; Remote Sensing; Physics, Applied SC Engineering; Remote Sensing; Physics GA BK50G UT WOS:000072374200191 ER PT S AU Andersen, G Knize, RJ AF Andersen, G Knize, RJ BE Bely, PY Breckinridge, JB TI Holographically corrected telescopes SO SPACE TELESCOPES AND INSTRUMENTS V, PTS 1-2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Space Telescopes and Instruments V Conference CY MAR 25-28, 1998 CL KONA, HI SP Int Soc Optical Engn, European So Observ DE holography; telescopes; aberrations; next generation space telescope AB Holographic correction of low-quality telescopes is an inexpensive method of obtaining large aperture devices suitable for lidar, imaging, and directed energy weaponry. We present an analysis of two different methods for producing diffraction-limited telescopes from the holographic correction of spherical mirrors. These evaluations are essential for choosing the optimal design for a given telescope application. Included in our discussion are the results from preliminary experiments into the various designs. The aim of the project is construct the first ever holographically corrected astronomical telescope for both ground and space-based operations. C1 USAF Acad, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. RP Andersen, G (reprint author), USAF Acad, Laser & Opt Res Ctr, 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 0-8194-2803-5 J9 P SOC PHOTO-OPT INS PY 1998 VL 3356 BP 773 EP 779 DI 10.1117/12.324495 PN 1-2 PG 7 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BL60U UT WOS:000075998200075 ER PT S AU Davis, TM Tomlinson, BJ AF Davis, TM Tomlinson, BJ BE Bely, PY Breckinridge, JB TI An overview of air force research laboratory cryogenic technology development programs SO SPACE TELESCOPES AND INSTRUMENTS V, PTS 1-2 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Space Telescopes and Instruments V Conference CY MAR 25-28, 1998 CL KONA, HI SP Int Soc Optical Engn, European So Observ 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, and Sorption cycle cryocoolers currently under development to meet current and future Air Force and DoD requirements. The AFRL customer single stage cooling requirements at 10K, 35K, 60K, 150K, and multi-stage cooling requirements at 35/60K 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), 60K and 100K thermal storage units and heat pipes, cryogenic straps, thermal switches, and development of an Integrated Lightweight Cryogenic Bus (CRYOBUS). C1 USAF, Res Lab, AFRL, VSSS, Kirtland AFB, NM 87117 USA. RP Davis, TM (reprint author), USAF, Res Lab, AFRL, VSSS, 3550 Aberdeen Ave SE,Bldg 30117 Manzano, Kirtland AFB, NM 87117 USA. NR 0 TC 3 Z9 3 U1 2 U2 6 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-2803-5 J9 P SOC PHOTO-OPT INS PY 1998 VL 3356 BP 1139 EP 1148 DI 10.1117/12.324513 PN 1-2 PG 10 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BL60U UT WOS:000075998200113 ER PT S AU Storz, MF AF Storz, MF BE Middour, JW Sackett, LL DAmario, LA Byrnes, DV TI Estimation of radar orientation, location and other calibration parameters using regularized residuals SO SPACEFLIGHT MECHANICS 1998, VOL 99, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 8th Annual Space Flight Mechanics Meeting CY FEB 09-11, 1998 CL MONTEREY, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut, AAS, Space Flight Mech Tech Comm, AIAA, Astrodynam Tech Comm AB Calibration of space surveillance radars to remove systematic biases is a cost-effective way to improve metric observation accuracy, leading to more accurate satellite orbit determination. Radar calibration can be performed more effectively today because of the many available reference orbits with submeter accuracy. CALIBRE, described in this paper, is a new algorithm that simultaneously estimates the values and covariances for sensor location, sensor clock bias, sensor orientation, isotropic range and range rate biases, and an ionospheric bias. CALIBRE transforms look angle (azimuth/elevation) residuals and look angle rate residuals into a localized angular coordinate frame that removes the geometric distortions that arise near the zenith, thus leading to better least squares estimates. Range, range rate, and range acceleration observations are also used as input. Look angle biases are estimated as a. single rigid-body rotation of the sensor axes, a method more physically realistic than the common practice of estimating a bias in azimuth and a bias in elevation as decoupled parameters. Operational application of CALL BRF: promises to provide significant improvements in the metric calibration of space surveillance radars and the resulting orbital accuracy. C1 Space Warfare Ctr, Falcon AFB, CO 80912 USA. RP Storz, MF (reprint author), Space Warfare Ctr, 730 Irwin Ave,Suite 83, Falcon AFB, CO 80912 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-450-8 J9 ADV ASTRONAUT SCI PY 1998 VL 99 BP 297 EP 316 PN 1&2 PG 20 WC Engineering, Aerospace SC Engineering GA BL82A UT WOS:000076812300017 ER PT S AU Vallado, DA AF Vallado, DA BE Middour, JW Sackett, LL DAmario, LA Byrnes, DV TI An analysis of the behavior of the J2000 reduction matrices SO SPACEFLIGHT MECHANICS 1998, VOL 99, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 8th Annual Space Flight Mechanics Meeting CY FEB 09-11, 1998 CL MONTEREY, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut, AAS, Space Flight Mech Tech Comm, AIAA, Astrodynam Tech Comm AB Accurate orbit determination relies on dense observational data and numerical processing. As existing analytical methods are replaced with highly accurate numerical techniques, we must use numerical integration methods that efficiently implement reduction calculations. The desirability to integrate and produce state vectors in varying frames requires efficient conversion methods. In addition, we often perform the numerical integration in the "inertial" mean-of-date frame (e.g. B1950, J2000), while the measurements and force model accelerations are found in the true-of-date frames. This paper investigates the behavior of the reduction matrices for precession, nutation, sidereal time, and polar motion and their impact on satellite position for use with acceleration calculations in a numerical integration program. Nutation receives the primary attention because it's the largest oscillatory effect. The paper finds that in some cases you can avoid many of the calculations-the time required to determine the complete reduction parameters isn't always necessary. It also shows graphical and timing analyses that show the approximations can save a significant amount of time while maintaining modest accuracy. Finally, output options in intermediate coordinate systems are discussed. The new ICRS may nullify many of the concerns addressed in this paper, but this analysis should prove useful until the ICRS is fully implemented. The overall conclusion is that the complete equations should be used for all highly accurate calculations with at least daily updates. The majority of the remaining cases can be updated once every few weeks, depending on the desired accuracy. C1 USAF, Res Lab, DEX, Kirtland AFB, NM 87117 USA. RP Vallado, DA (reprint author), USAF, Res Lab, DEX, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-450-8 J9 ADV ASTRONAUT SCI PY 1998 VL 99 BP 783 EP 801 PN 1&2 PG 19 WC Engineering, Aerospace SC Engineering GA BL82A UT WOS:000076812300049 ER PT S AU Fischer, JD Cefola, PJ Proulx, RJ AF Fischer, JD Cefola, PJ Proulx, RJ BE Middour, JW Sackett, LL DAmario, LA Byrnes, DV TI Modeling catastrophic decay orbits through perigee SO SPACEFLIGHT MECHANICS 1998, VOL 99, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 8th Annual Space Flight Mechanics Meeting CY FEB 09-11, 1998 CL MONTEREY, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut, AAS, Space Flight Mech Tech Comm, AIAA, Astrodynam Tech Comm AB As highly eccentric orbits decay, their passage through perigee acts as a major perturbation due to highly dynamic atmospheric effects. In order to better model the catastrophic decay these orbits face, the authors will do a brief analysis of the modeling errors for various atmospheric effects. Using data from an upper stage SL-6 Molniya rocket body, the errors identified in these analyses will be used to define a functional representation of the process noise. The results of incorporating this function into a Kalman Filter are presented. C1 USAF, Washington, DC 20330 USA. RP Fischer, JD (reprint author), USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-450-8 J9 ADV ASTRONAUT SCI PY 1998 VL 99 BP 1215 EP 1234 PN 1&2 PG 20 WC Engineering, Aerospace SC Engineering GA BL82A UT WOS:000076812300076 ER PT S AU Marasch, MW Hall, CD AF Marasch, MW Hall, CD BE Middour, JW Sackett, LL DAmario, LA Byrnes, DV TI Flywheel energy storage applied to solar electric propulsion SO SPACEFLIGHT MECHANICS 1998, VOL 99, PTS 1 AND 2 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 8th Annual Space Flight Mechanics Meeting CY FEB 09-11, 1998 CL MONTEREY, CA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut, AAS, Space Flight Mech Tech Comm, AIAA, Astrodynam Tech Comm AB In this paper, we investigate the application of flywheel energy storage to minimum-time, constant-thrust orbital maneuvers using solar electric propulsion. Techniques for solving several resulting boundary value problems are developed. Tradeoffs between solar array and flywheel battery masses are explored for transfers requiring multiple revolutions. The effects of several parameters on these tradeoffs are examined. The utility of fiywheel energy storage specifically for the use of the solar electric propulsion system is examined. We find that when flywheel energy storage is used in these scenarios, transit times are typically increased, but significant propellant mass savings can be realized. If the spacecraft has a requirement for energy storage, then it is advantageous to use it during orbit transfer. C1 USAF, Res Lab, VSDD, Kirtland AFB, NM 87117 USA. RP Marasch, MW (reprint author), USAF, Res Lab, VSDD, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-450-8 J9 ADV ASTRONAUT SCI PY 1998 VL 99 BP 1469 EP 1487 PN 1&2 PG 19 WC Engineering, Aerospace SC Engineering GA BL82A UT WOS:000076812300091 ER PT S AU Cowan, WD Bright, VM Lee, MK Comtois, JH Michalicek, MA AF Cowan, WD Bright, VM Lee, MK Comtois, JH Michalicek, MA BE Sutherland, RL TI Design and testing of polysilicon surface micromachined piston micromirror arrays SO SPATIAL LIGHT MODULATORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spatial Light Modulators CY JAN 28-29, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE micro-electro-mechanical systems (MEMS); micro-opto-electro-mechanical systems; micromirrors AB This paper presents optical testing of polysilicon surface micromachined piston micromirror arrays. Similar piston micromirror arrays were fabricated using two different commercially available surface micromachining foundry processes: the DARPA supported Multi-User MEMS Processes (MUMPs), and Sandia Ultra-planar Multi-level MEMS Technology (SUMMiT). All test arrays employ square reflecting elements in an 8 x 8 element 203 mu m square grid. Fabrication constraints limit the MUMPs designs to fill-factors of less than 80%. The chemical mechanical polishing planarization step integral to the SUMMiT process allows an as-drawn fill-factor of 95% to be easily achieved. MUMPs designs employ both the standard gold metallization and maskless sputtered chromium/gold post-process metallization, while post process metallization is the only option for the SUMMiT design. Testing of the micromirror arrays focuses on microscope interferometer characterization of mirror topography, and measurement of the far field diffraction pattern for each. The measured results show that control of the individual micromirror element surface topography is more important for imaging applications than maximizing the as-drawn fill-factor. C1 USAF, Inst Technol, Dept Elect & Comp Engn, ENG, Wright Patterson AFB, OH 45433 USA. RP Cowan, WD (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, ENG, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 5 Z9 5 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 0-8194-2731-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3292 BP 60 EP 70 DI 10.1117/12.305508 PG 11 WC Optics SC Optics GA BL04N UT WOS:000074113100007 ER PT S AU Michalicek, MA Comtois, JH Schriner, HK AF Michalicek, MA Comtois, JH Schriner, HK BE Sutherland, RL TI Development of advanced second-generation micromirror devices fabricated in a four-level, planarized surface micromachined polycrystalline silicon process SO SPATIAL LIGHT MODULATORS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Spatial Light Modulators CY JAN 28-29, 1998 CL SAN JOSE, CA SP Soc Photo Opt Instrumentat Engineers DE MEMS; micromirrors; optical MEMS; MOEMS; CMP planarization; SUMMiT; spatial light modulators AB This paper describes the design and characterization of several types of micromirror devices to include process capabilities, device modeling, and test data resulting in deflection versus applied potential curves and surface contour measurements. These devices are the first to be fabricated in the state-of-the-art four-level planarized polysilicon process available at Sandia National Laboratories known as the Sandia Ultra-planar Multi-level MEMS Technology (SUMMiT). This enabling process permits the development of micromirror devices with near-ideal characteristics which have previously been unrealizable in standard three-layer polysilicon processes. This paper describes such characteristics as elevated address electrodes, various address wiring techniques, planarized mirror surfaces using Chemical Mechanical Polishing (CMP), unique post-process metallization, and the best active surface area to date. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Michalicek, MA (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 TC 5 Z9 5 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 0-8194-2731-4 J9 P SOC PHOTO-OPT INS PY 1998 VL 3292 BP 71 EP 80 DI 10.1117/12.305509 PG 10 WC Optics SC Optics GA BL04N UT WOS:000074113100008 ER PT J AU Hagino, RT Valentine, RJ Clagett, GP AF Hagino, RT Valentine, RJ Clagett, GP TI Asymptomatic carotid stenosis and anatomically remote surgery: Should we be more aggressive? SO STROKE LA English DT Meeting Abstract C1 Univ Texas, SW Med Ctr, Dallas, TX USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0039-2499 J9 STROKE JI Stroke PD JAN PY 1998 VL 29 IS 1 MA P190 BP 334 EP 334 PG 1 WC Clinical Neurology; Peripheral Vascular Disease SC Neurosciences & Neurology; Cardiovascular System & Cardiology GA YQ726 UT WOS:000071417100330 ER PT J AU Soref, RA Friedman, L Sun, G AF Soref, RA Friedman, L Sun, G TI Silicon intersubband lasers SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article DE semiconductor lasers; silicon; germanium; quantum wells ID CONTINUOUS-WAVE OPERATION; QUANTUM CASCADE LASERS; WELL AB The critical design issues for unipolar silicon quantum-well intersubband lasers an investigated in this paper. Group IV lasing at near-infrared and middle-infrared wavelengths is analyzed for surface-emitting and edge-emitting geometries. Calculations show feasibility of SiGe/Si and SiGeC/Si lasing. Silicon-on-insulator structures are proposed for index-guided lasers, vertical-cavity lasers and micro-cavity lasers. (C) 1998 Academic Press Limited. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. Univ Massachusetts, Dept Phys, Boston, MA 02125 USA. RP Soref, RA (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 17 TC 14 Z9 14 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0749-6036 J9 SUPERLATTICE MICROST JI Superlattices Microstruct. PY 1998 VL 23 IS 2 BP 427 EP 439 DI 10.1006/spmi.1996.0448 PG 13 WC Physics, Condensed Matter SC Physics GA ZA747 UT WOS:000072396800037 ER PT B AU Lombard, CM Ghosh, AK Semiatin, SL AF Lombard, CM Ghosh, AK Semiatin, SL BE Ghosh, AK Bieler, TR TI Influence of concurrent microstructural changes on the superplastic deformation behavior of a near-gamma titanium aluminide alloy SO SUPERPLASTICITY AND SUPERPLASTIC FORMING 1998 LA English DT Proceedings Paper CT Conference on Superplasticity and Superplastic Forming at the 1998 TMS Annual Meeting CY FEB 16-19, 1998 CL SAN ANTONIO, TX SP Minerals Met & Mat Soc, Shaping & Forming Comm AB The uniaxial hot tension behavior of a near-gamma titanium aluminide alloy sheet (Ti-45.5Al-2Cr-2Nb) was determined in the as-rolled (initial grain size approximate to 3 to 5 mu m) and rolled-and-heat treated (1177 degrees C/4 hours or 1238 degrees C/2 hours) conditions (initial grain size approximate to 10 to 12 mu m). Microstructural evolution, cavitation rates, and failure modes were established via isothermal constant strain rate tests conducted at 10(-4) sec(-1) to 10(-2) sec(-1) and test temperatures between 900 degrees C and 1200 degrees C. Interrupted and strained-to-failure tests were conducted in order to track dynamic microstructural changes with time. Experimentally derived cavity growth rates were compared with various equations which predict cavity growth rates as a function of strain rate sensitivity. Selected equations were found to be better in their ability to describe the cavity growth rate. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, Wright Patterson AFB, OH 45433 USA. RP Lombard, CM (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 0 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 0-87339-398-8 PY 1998 BP 267 EP 275 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA BK53H UT WOS:000072464600027 ER PT B AU West, DA AF West, DA GP AMS TI The use of SSM/I rainfall to predict eastern North Pacific tropical cyclone intensity change SO SYMPOSIUM ON TROPICAL CYCLONE INTENSITY CHANGE LA English DT Proceedings Paper CT Symposium on Tropical Cyclone Intensity Change CY JAN 11-16, 1998 CL PHOENIX, AZ SP Amer Meteorol Soc C1 Ohio State Univ, USAF, Inst Technol, Civilian Inst Program,Atmospher Sci Program, Columbus, OH 43210 USA. RP West, DA (reprint author), 1049 Derby Hall,154 N Oval Mall, Columbus, OH 43210 USA. NR 0 TC 0 Z9 2 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 1998 BP 49 EP 50 PG 2 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA BL98E UT WOS:000077346700011 ER PT B AU Keil, SL Henry, TW Fleck, B AF Keil, SL Henry, TW Fleck, B BE Balasubramaniam, KS Harvey, JW Rabin, DM TI NSO/AFRL/Sac peak K-line monitoring program SO SYNOPTIC SOLAR PHYSICS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 18th National-Solar-Observatory/Sacramento-Peak Summer Workshop on Synoptic Solar Physics CY SEP 08-12, 1997 CL SUNSPOT, NM SP Natl Solar Observ, Natl Optical Astron Observ, Natl Sci Fdn, Div Atmospher Sci, NASA, Space Sci Div, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Air Force Res Lab, Space Hazards Branch AB We summarize the National Solar Observatory/Air Force Research Lab/Sacramento Peak synoptic Calcium K-line monitoring program that was initiated in November of 1976. We observe the disk-integrated solar Ca II K-line using the Evans Coronal Facility at NSO/SP. Several K-line parameters, including the emission index and various measures of asymmetry are computed from the calibrated line profiles. We discuss the cyclic variation of these K-line parameters and their correlation with a several other solar variability indicators. C1 USAF, Res Lab, Sunspot, NM 88349 USA. RP Keil, SL (reprint author), USAF, Res Lab, Sunspot, NM 88349 USA. RI Fleck, Bernhard/C-9520-2012 NR 0 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 1-886733-60-0 J9 ASTR SOC P PY 1998 VL 140 BP 301 EP 309 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL74T UT WOS:000076547800031 ER PT B AU Altrock, RC AF Altrock, RC BE Balasubramaniam, KS Harvey, JW Rabin, DM TI Variation of solar coronal intensity and temperature in cycle 22 SO SYNOPTIC SOLAR PHYSICS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 18th National-Solar-Observatory/Sacramento-Peak Summer Workshop on Synoptic Solar Physics CY SEP 08-12, 1997 CL SUNSPOT, NM SP Natl Solar Observ, Natl Optical Astron Observ, Natl Sci Fdn, Div Atmospher Sci, NASA, Space Sci Div, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Air Force Res Lab, Space Hazards Branch AB Observations at 1.15 solar radii of the forbidden coronal lines Fe XIV 530.3 nm and Fe X 637.4 nm obtained at the National Solar Observatory at Sacramento Peak are used to determine the variation of coronal intensity and temperature during Cycle 22. Coronal intensity generally follows the usual solar-cycle variation, but interesting departures occur at high latitude. Additionally, the southern hemisphere is brighter than the north throughout the cycle. Temporal averages of coronal temperature are calculated, and an unexpected pattern, approximately symmetric about solar maximum and consistent between the northern and southern hemisphere, is seen. Beginning near solar minimum in 1985, the temperature above 60 degrees latitude is seen to be at a minimum value, varying from about 1.3 MK near the poles to about 1.5 MK near 60 degrees. Near the time that the "Rush to the Poles" begins in 1987, the high-latitude temperature increases abruptly, reaching values of 1.7 MK at the North pole and 1.6 MK at the South pole in 1989. After 1990, the process reverses, and temperatures at the poles are below 1.3 MK by 1995. C1 USAF, Res Lab, Natl Solar Observ, Sunspot, NM 88349 USA. RP Altrock, RC (reprint author), USAF, Res Lab, Natl Solar Observ, Sacramento Peak, Sunspot, NM 88349 USA. NR 0 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 1-886733-60-0 J9 ASTR SOC P PY 1998 VL 140 BP 339 EP 345 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL74T UT WOS:000076547800036 ER PT B AU Cliver, EW Bounar, KH Boriakoff, V AF Cliver, EW Bounar, KH Boriakoff, V BE Balasubramaniam, KS Harvey, JW Rabin, DM TI Geomagnetic activity and the solar wind during the Maunder Minimum SO SYNOPTIC SOLAR PHYSICS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 18th National-Solar-Observatory/Sacramento-Peak Summer Workshop on Synoptic Solar Physics CY SEP 08-12, 1997 CL SUNSPOT, NM SP Natl Solar Observ, Natl Optical Astron Observ, Natl Sci Fdn, Div Atmospher Sci, NASA, Space Sci Div, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Air Force Res Lab, Space Hazards Branch AB We used a strong (r = 0.96) correlation between Ii-year averages of sunspot number (SSN) and the geomagnetic aa index to infer that the mean level of geomagnetic activity during the Maunder Minimum (1645-1715) was approximately a third of that observed for recent solar cycles (similar to 7 nT vs. similar to 24 nT). This result is consistent with reported radiocarbon measurements. We determined the variation of Ii-year averages of solar wind speed (v) and the southward component of the interplanetary magnetic field (B-s) with cycle-averaged SSN for the two most recent cycles and also compared cycle-averaged variations of v(2)B(s)) and aa for the same interval. We then extrapolated these observed solar wind variations to Maunder Minimum conditions (mean SSN of similar to 2 and mean aa value of similar to 7 nT) to deduce that, on average, the solar wind during that period was somewhat slower (v = 340+/-50 km s(-1)), and the interplanetary magnetic field much smoother (B-s = 0.3 +/- 0.1 nT),;than at present (440 km s(-1) and 1.2 nT). Various lines of evidence (including Be-10 data) suggest that, despite the virtual absence of sunspots that characterized the Maunder Minimum, the Ii-year geomagnetic (solar wind) cycle persisted throughout this period. During the last half of the 17th Century, it appears that yearly aa values varied between NO nT at minima of Ii-year cycles and similar to 10-15 nT at maxima. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Cliver, EW (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 0 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 1-886733-60-0 J9 ASTR SOC P PY 1998 VL 140 BP 437 EP 444 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL74T UT WOS:000076547800047 ER PT B AU Neidig, D Wiborg, P Confer, M Haas, B Dunn, R Balasubramaniam, KS Gullixson, C Craig, D Kaufman, M Hull, W McGraw, R Henry, T Rentschler, R Keller, C Jones, H Coulter, R Gregory, S Schimming, R Smaga, B AF Neidig, D Wiborg, P Confer, M Haas, B Dunn, R Balasubramaniam, KS Gullixson, C Craig, D Kaufman, M Hull, W McGraw, R Henry, T Rentschler, R Keller, C Jones, H Coulter, R Gregory, S Schimming, R Smaga, B BE Balasubramaniam, KS Harvey, JW Rabin, DM TI The USAF Improved Solar Observing Optical Network (ISOON) and its impact on solar synoptic data bases SO SYNOPTIC SOLAR PHYSICS SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 18th National-Solar-Observatory/Sacramento-Peak Summer Workshop on Synoptic Solar Physics CY SEP 08-12, 1997 CL SUNSPOT, NM SP Natl Solar Observ, Natl Optical Astron Observ, Natl Sci Fdn, Div Atmospher Sci, NASA, Space Sci Div, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Air Force Res Lab, Space Hazards Branch AB The Air Force Research Laboratory's Space Hazards Branch, in partnership with the National Solar Observatory at Sacramento Peak, is developing prototype instrumentation and software for the Improved Solar Observing Optical Network (ISOON). ISOON will replace the existing SOON system which was designed and deployed in the 1970s for space weather specifications and forecasting. ISOON will feature autonomous, rapid-cadence solar imaging spectroscopy and imaging spectropolarimetry, at four sites around the world, while transmitting solar images in near real time to central analysis facilities at Air Force Space Command and NOAA/SEC. The ISOON technical approach is to retain the front end of the existing SOON telescope, but replace the optical bench, birefringent filter, and spectrograph with a dual Fabry-Perot filter system, CCD array detector, and secondary optics contained in a pod behind the main telescope tube. ISOON data products will include full-sun images (on 1-arcsecond pixels) in H alpha (acquired 1 per minute), continuum (1 per hour), and line-of-sight magnetic field (1 per 3 hours), as well as parameterized data such as flare brightness, location, area, and times of onset and maximum. Limited-field-of-view, high resolution images (on 0.3-arcsecond pixels) will be a capability developed in the design of the prototype instrument, and may be accommodated as a future upgrade in the operational units. ISOON will also be capable of acquiring transverse magnetic field images, via a future software modification. The unofficial position of the USAF is to allow the solar community access to all of the ISOON imaging data. In principle, the data would be available almost immediately, following its arrival at the central facility. Provision is being made by USAF for temporary storage of the data, during which time the archive would be open for retrieval of images. Considering the 24-hour coverage, 1-minute cadence, image intensity normalization, frame selection, atmospheric refraction correction, and constant image diameter and P-angle orientation, the ISOON images will have the potential of providing a mainstay of solar synoptic data for the scientific community. The realization of such potential, however, will require that the scientific community take an initiative to ensure the orderly collection permanent archival, and easy access and dissemination of the ISOON data. C1 USAF, Res Lab, Space Hazards Branch, Natl Solar Observ, Sunspot, NM 88349 USA. RP Neidig, D (reprint author), USAF, Res Lab, Space Hazards Branch, Natl Solar Observ, Sunspot, NM 88349 USA. NR 0 TC 28 Z9 28 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-886733-60-0 J9 ASTR SOC P PY 1998 VL 140 BP 519 EP 528 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BL74T UT WOS:000076547800055 ER PT S AU Rothman, LS Rinsland, CP Goldman, A Massie, ST Edwards, DP Flaud, JM Perrin, A Camy-Peyret, C Dana, V Mandin, YY Schroeder, J Gamache, RR Wattson, RB Yoshino, K Chance, KV Jucks, KW Brown, LR Nemtchinov, V Varanasi, P AF Rothman, LS Rinsland, CP Goldman, A Massie, ST Edwards, DP Flaud, JM Perrin, A Camy-Peyret, C Dana, V Mandin, YY Schroeder, J Gamache, RR Wattson, RB Yoshino, K Chance, KV Jucks, KW Brown, LR Nemtchinov, V Varanasi, P BE Watkins, WR Clement, D TI The HITRAN molecular spectroscopic database and HAWKS (HITRAN atmospheric workstation) SO TARGETS AND BACKGROUNDS: CHARACTERIZATION AND REPRESENTATION IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Targets and Backgrounds - Characterization and Representation IV CY APR 13-15, 1998 CL ORLANDO, FL SP SPIE AB Nineteen ninety-eight marks the 25(th) anniversary of the release of the first HITRAN database. HITRAN is recognized as the international standard of the fundamental spectroscopic parameters for diverse atmospheric and laboratory transmission and radiance calculations. There have been periodic editions of HITRAN over the past decades as the database has been expanded and improved with respect to the molecular species and spectral range covered, the number of parameters included, and the accuracy of this information. The 1996 edition not only includes the customary line-by-line transition parameters familiar to HITRAN users, but also cross-section data, aerosol indices of refraction, software to filter and manipulate the data, and documentation. This paper describes the data and features that have been added or replaced since the previous edition of HITRAN. We also cite instances of critical data that is forthcoming. A new release is planned for 1998. C1 USAF, VSBM, Hanscom AFB, MA 01731 USA. RP Rothman, LS (reprint author), USAF, VSBM, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 0 TC 3 Z9 3 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 0-8194-2824-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3375 BP 123 EP 132 DI 10.1117/12.327146 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL58S UT WOS:000075942300013 ER PT S AU Ferris, DD Currie, NC AF Ferris, DD Currie, NC BE Watkins, WR Clement, D TI Microwave and millimeter-wave systems for wall penetration SO TARGETS AND BACKGROUNDS: CHARACTERIZATION AND REPRESENTATION IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Targets and Backgrounds - Characterization and Representation IV CY APR 13-15, 1998 CL ORLANDO, FL SP SPIE DE through-the-wall surveillance; millimeter wave radar; millimeter wave radiometry; microwave radar AB The need for through-the-wall surveillance sensors has existed for many years. Recent advances in microwave and millimeter-wave (MMW) technologies provide new applications for law enforcement use. These applications include the potential to conduct surveillance through walls and the ability to detect the presence of living persons behind doors or other barriers. Covert surveillance and personnel detection are of high interest to both the Department of Defense in support of Small Unit Operations (SUO) and the Justice Department for civilian law enforcement applications. Microwave sensors are under development that can detect the presence of persons land even weapons) behind walls and track moving persons behind walls. MMW sensors are under development which can provide pseudo-images of persons behind walls including radiometric sensors at 95 GHz, active 95 GHz real aperture radars, and heartbeat detection radars. Radiometric sensors include 2-D FPA systems, I-D FPA, scanned systems, and single element scanned sensors. Active FPA radars include illuminated radiometric systems and coherent radar systems. Real aperture MMW radar systems include raster scanned and non-scanned (hand-held) sensors. C1 USAF, Res Lab, AFRL, IFEA, Griffiss AFB, NY 13441 USA. RP Ferris, DD (reprint author), USAF, Res Lab, AFRL, IFEA, Griffiss AFB, NY 13441 USA. NR 0 TC 20 Z9 20 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 0-8194-2824-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3375 BP 269 EP 279 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL58S UT WOS:000075942300027 ER PT S AU Lowry, HS Doub, CA Holt, LL Steely, SL Fugerer, RH AF Lowry, HS Doub, CA Holt, LL Steely, SL Fugerer, RH BE Watkins, WR Clement, D TI Development of laser-based direct write projection methods: Sensor optics and system characterization issues SO TARGETS AND BACKGROUNDS: CHARACTERIZATION AND REPRESENTATION IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Targets and Backgrounds - Characterization and Representation IV CY APR 13-15, 1998 CL ORLANDO, FL SP SPIE DE acousto-optic; scene projection; infrared; radiometric; focal plane arrays; closed-loop; lens; crosstalk AB This paper describes the investigation and potential utility of using the Direct Write Scene Generator (DWSG) to project onto a sensor system's focal plane array (FPA) through its optical telescope. The test approach requires development of magnifier/collimator systems to expand the DWSG output to the sensor telescope. A lens system has been procured to facilitate the projection to the full array of a standard CCD with an attached lens system. A demonstration of operation of the DWSG through camera optics has been recorded. The capability of the DWSG system to measure FPA crosstalk has been examined in some detail. C1 Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. RP Lowry, HS (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. NR 0 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 0-8194-2824-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3375 BP 292 EP 303 DI 10.1117/12.327162 PG 12 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BL58S UT WOS:000075942300030 ER PT J AU Brockway, JH Bryant, FB AF Brockway, JH Bryant, FB TI You can't judge a measure by its label: Teaching the process of instrumentation SO TEACHING OF PSYCHOLOGY LA English DT Article; Proceedings Paper CT Meeting of the American-Psychological-Society-Institute-on-the-Teaching-of-Psychology CY JUN, 1996 CL SAN FRANCISCO, CALIFORNIA SP Amer Psychol Soc Inst Teaching Psychology AB In this article, we describe an exercise In instrument selection applicable to both undergraduate and graduate courses. The exercise consists of 5 progressive steps that involve choosing and defining a theoretical construct (Steps 1 and 2), wing computer-based technology to obtain 2 distinct instruments that measure this construct (Steps 3 and 4), and comparing and contrasting these 2 instruments along multiple dimensions (Step 5). This activity generates awareness of the issues involved in measuring latent constructs and teaches at least 3 lessons: (a) The Ist seep to accurate instrumentation is precisely conceptualizing the construct of interest; (b) there is more than 1 way to measure latent constructs, and these multiple approaches should be compared; and (c) it is crucial to measure a construct in a way that best matches its underlying definition. C1 USAF Acad, DFBL, HQ, Colorado Springs, CO 80840 USA. Loyola Univ, Chicago, IL 60611 USA. RP Brockway, JH (reprint author), USAF Acad, DFBL, HQ, 2354 Fairchild Dr,Suite 6L47, Colorado Springs, CO 80840 USA. NR 9 TC 0 Z9 0 U1 10 U2 10 PU LAWRENCE ERLBAUM ASSOC INC PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430-2262 USA SN 0098-6283 J9 TEACH PSYCHOL JI Teach. Psychol. PY 1998 VL 25 IS 2 BP 121 EP 123 DI 10.1207/s15328023top2502_10 PG 3 WC Education & Educational Research; Psychology, Multidisciplinary SC Education & Educational Research; Psychology GA ZM174 UT WOS:000073512100011 ER PT S AU Huber, EG Courtney, RA Geiser, AG AF Huber, EG Courtney, RA Geiser, AG BE Murrer, RL TI Assessment of the Wideband Infrared Scene Projector (WISP) using conventional IR seekers SO TECHNOLOGIES FOR SYNTHETIC ENVIRONMENTS: HARDWARE-IN-THE-LOOP TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Technologies for Synthetic Environments - Hardware-in-the-Loop Testing III CY APR 13-15, 1998 CL ORLANDO, CA SP SPIE DE IR seeker testing; IR scene projection; WISP AB The Wideband Infrared Scene Projector (WISP) was developed to project dynamic, detailed scenes to imaging infrared (IR) missile seekers. However, the vast majority of IR seekers currently in inventory are nonimaging and pseudo-imaging reticle-based seekers. Air Force Research Laboratory's (AFRL) Dynamic Infrared Missile Evaluator (DIME) Facility is interested in the response of these conventional seekers to detailed IR scenes, as would be encountered in the final phase of a missile engagement. Conventional seekers have different scene projection requirements than the imaging seekers for which the WISP was designed. To assess the applicability of an IR scene projector for testing conventional seekers, DIME Facility personnel used two reticle-based seekers to measure spatial and temporal characteristics of the WISP. A description of the testing performed and the results obtained are presented in this paper. C1 USAF, Res Lab, EO Warfare Branch, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Huber, EG (reprint author), USAF, Res Lab, EO Warfare Branch, Sensors Directorate, 2241 Avion Circle,Suite 2, Wright Patterson AFB, OH 45433 USA. NR 0 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 0-8194-2817-5 J9 P SOC PHOTO-OPT INS PY 1998 VL 3368 BP 166 EP 174 PG 9 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL58R UT WOS:000075941600016 ER PT S AU Steely, SL Nicholson, RA Kiech, EL Mead, KD Lowry, HS AF Steely, SL Nicholson, RA Kiech, EL Mead, KD Lowry, HS BE Murrer, RL TI Scene generation and projection technologies: Real-time methodologies and validation efforts SO TECHNOLOGIES FOR SYNTHETIC ENVIRONMENTS: HARDWARE-IN-THE-LOOP TESTING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Technologies for Synthetic Environments - Hardware-in-the-Loop Testing III CY APR 13-15, 1998 CL ORLANDO, CA SP SPIE DE sensor testing; point spread function; wavefront error; optical fidelity; validation; optical diagnostics; cryogenics; vacuum; Levenberg-Marquardt; nonlinear curve fitting AB An advanced sensor test facility, located at Arnold Engineering Development Center (AEDC) has been designed for sensor calibration and performance characterization of advanced infrared sensors for strategic and tactical systems. During the past few years a sensor test facility, known as the 7V Chamber, has been used to support the Army's Interceptor Programs. This chamber complements other focal-plane-array and sensor-test capabilities developed at AEDC to provide ground-test support for strategic and tactical sensor systems. The 7V Chamber is a state-of-the-art cryo-vacuum facility providing calibration and high-fidelity mission simulation using complex backgrounds and targets. This paper describes a validation effort for determining the point spread function (PSF) and corresponding wavefront errors. A method is described for measuring a highly under-sampled PSF and determining the corresponding wavefront error. This method employs a knife-edge distribution inversion of Bessel-distributed densities with a Gaussian approximation to implement a nonlinear least-squares functional fit using a Levenberg-Marquardt method. C1 Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. RP Steely, SL (reprint author), Sverdrup Technol Inc, AEDC Grp, 1077 Ave C,MS-6400, Arnold AFB, TN 37389 USA. NR 0 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 0-8194-2817-5 J9 P SOC PHOTO-OPT INS PY 1998 VL 3368 BP 224 EP 236 DI 10.1117/12.316368 PG 13 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BL58R UT WOS:000075941600021 ER PT S AU Rud, VY Rud, YV Ohmer, MC Schunemann, PG AF Rud, VY Rud, YV Ohmer, MC Schunemann, PG BE Tomlinson, RD Hill, AE Pilkington, RD TI Characterization of ZnGeP2 single crystals grown by low temperature crystallization SO TERNARY AND MULTINARY COMPOUNDS SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT 11th International Conference on Ternary and Multinary Compounds (ICTMC-11) CY SEP 08-12, 1997 CL UNIV SALFORD, SALFORD, ENGLAND HO UNIV SALFORD AB Single crystals of the chalcopyrite compound ZnGeP2 were grown from the nonstoichiometric melts by the gradient freezing. Physical properties of ZnGeP2 homogeneity bulk crystals and In/ZnGeP2 surface-barrier structures on them are reported. The luminescence spectra reveal a broad infrared emission with a peak position 1.25-1.44 eV at T=80 K. It was founding that these peak shifts to the short-wavelength region as the pumping level increases that exhibits features of donor-acceptor recombination. The photosensitivity of In/ZnGeP2 structures at the long-wavelength region decreased as a results of the reduced crystallization temperature. C1 State Tech Univ, St Petersburg 195251, Russia. Russian Acad Sci, Ioffe Phys Tech Inst, St Petersburg 194021, Russia. Wright Lab, Wright Patterson AFB, OH 45433 USA. Lockheed Sanders, Nashua, NH 03061 USA. RP Rud, VY (reprint author), State Tech Univ, 29 Polytekhnicheskaya St, St Petersburg 195251, Russia. NR 8 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0951-3248 BN 0-7503-0438-3 J9 INST PHYS CONF SER PY 1998 VL 152 BP 127 EP 130 PG 4 WC Crystallography; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics; Physics, Applied; Physics, Multidisciplinary SC Crystallography; Materials Science; Optics; Physics GA BK92V UT WOS:000073874800029 ER PT S AU Allred, LG AF Allred, LG BE Snell, JR Wurzbach, RN TI Identification of age degradation in EPROM chips using infrared thermography SO THERMOSENSE XX SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Thermosense XX CY APR 14-16, 1998 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers AB In a recent upgrade of the Digital Flight Control Computer (DFLCC) for the F-16, there was serious consternation expressed about the quality of the soldering repair process. Dozens of circuit cards (about 5% of the total) failed to function after the upgrade, even though all of these cards operated correctly before the modifications. The shop called for the use of the infrared camera to assist in diagnosing and repairing these cards. What the Neural Radiant Energy Detection (NREDS) found was faulty and marginal chips. Of particular interest was the presence of degraded EPROM chips on the Program Memory (PM) cards. While it is known that EPROMs have a limited life cycle (in terms of number of total recordings), the failure has been further characterized. Thermography provides a quantification of the degradation in thermal performance as the EPROMs are reused. Pristine EPROM chips have a rise rate of about 0.008 degrees C/sec. When the heat rates exceed 0.021 degrees C/sec, the EPROM chips will not accept a program. Some of the chips exhibited heat rates exceeding 0.1 degrees C/sec. Some chips with degradation of 0.018 degrees C/sec would accept a program, but fail other functional tests. What is clear from these results is that infrared thermography can be used to identify degrading EPROM chips for replacement before failures become immanent. C1 Ogden Air Logist Ctr, Software Engn Div, TIS, Hill AFB, UT 84056 USA. RP Allred, LG (reprint author), Ogden Air Logist Ctr, Software Engn Div, TIS, Hill AFB, UT 84056 USA. NR 0 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 0-8194-2810-8 J9 P SOC PHOTO-OPT INS PY 1998 VL 3361 BP 35 EP 39 DI 10.1117/12.304749 PG 5 WC Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics SC Instruments & Instrumentation; Materials Science; Optics GA BL17D UT WOS:000074540100004 ER PT S AU Hazzledine, PM Grinfeld, MA Rao, SI AF Hazzledine, PM Grinfeld, MA Rao, SI BE Cammarata, RC Nastasi, M Busso, EP Oliver, WC TI Coherency and loss of coherency in multilayers SO THIN-FILMS - STRESSES AND MECHANICAL PROPERTIES VII SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Thin-Films - Stresses and Mechanical Properties VII at the MRS Fall Meeting CY DEC 01-05, 1997 CL BOSTON, MA SP Mat Res Soc AB A multilayer consisting of parallel sided, elastically isotropic layers with thicknesses much smaller than their dimensions in the plane of the layers may develop large coherency stresses when the layers are thin enough. General formulae are given for the stress tensors in a flat periodic fully coherent multilayer which may contain any number of layers, each with different lattice parameters, elastic constants and thicknesses. As the thicknesses of the layers increase there is an increasing tendency for the interfaces to become incoherent thereby relaxing the elastic stresses, at the expense of creating higher energy interfaces between the layers. This tendency is particularly marked for unusually thick or unusually rigid layers or for layers with very large or small lattice parameters. Unlike the case of thin films on massive substrates, there is no single thickness at which coherency is lost. In this paper, the loss of coherency is explored by searching for energy minima in irregular multilayers. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Hazzledine, PM (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 3 Z9 3 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-410-6 J9 MATER RES SOC SYMP P PY 1998 VL 505 BP 179 EP 184 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films SC Materials Science GA BL54X UT WOS:000075849800025 ER PT B AU Pinkus, A Task, HL AF Pinkus, A Task, HL GP SAFE SAFE TI Measuring observers' visual acuity through night vision goggles SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB Use of night vision goggles (NVGs) for military applications has grown steadily over the past 30 years. Each successive NVG model represents some kind of improvement in terms of size, weight ruggedness, gain, noise, spectral sensitivity, field-of-view or resolution. The primary focus of this paper is the determination of NVG resolution Many methods have been devised to measure the resolving power of NVGs and each method has with if an associated variance or accuracy of measurement. This variance is mast likely caused by several sources including observer visual capability (since most methods involve visual observations and judgement to assess NVG resolution). The main purpose of this paper is to present the different methods that have been used to assess NVG resolution and to determine to what extent observer visual capability limits the accuracy of NVG resolution measurement. This study uses a methodology that measures an observer's psychometric function when viewing through NVGs (percent correct detection as a function of spatial separation) to determine their visual acuity using probit analysis. C1 USAF, Res Lab, Human Effectiveness Directorate, HECV, Wright Patterson AFB, OH 45433 USA. RP Pinkus, A (reprint author), USAF, Res Lab, Human Effectiveness Directorate, HECV, 2255 H St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 1 EP 11 PG 11 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200001 ER PT B AU Marasco, PL Pinkus, AR Task, HL AF Marasco, PL Pinkus, AR Task, HL GP SAFE SAFE TI Photographic assessment of dark spots in night vision device images SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB Visible defects in night vision device (NVD) images, arising from image intensifier (I-2) tube defects and dirt on the device's optics, can become more than cosmetic blemishes. They can act as visual distractions and may be large enough to mask critical information pilots need to conduct normal night vision operations. This paper is concerned with the assessment of NVD dark spots. Current methods of assessing dark spots examine only the image intensifier tube, ignoring spots due to dirt and dust introduced during night vision device assembly. Current methods are limited in the size of spot that can be counted and do nor address the issue of spot contrast This paper discusses a photographic method for classifying, locating and counting dark spots in an assembled night vision device. Also documented in this paper is an experiment to determine an observer's ability to classify round dark spots, conducted as part of an effort to determine the accuracy of the photographic test procedure. To quantify the defects, they were classified by size and then counted. Inspectors used a comparison key as an aid in categorizing dots by size. The defect specification should not exceed the classifiers' visual discrimination capabilities. This study directly examined the dot size classification performance of observers using dots of 3, 4, and 6 minutes of arc (MOA) in diameter. C1 USAF, Res Lab, Human Effectiveness Directorate, HECV, Wright Patterson AFB, OH 45433 USA. RP Marasco, PL (reprint author), USAF, Res Lab, Human Effectiveness Directorate, HECV, 2255 H St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 20 EP 25 PG 6 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200003 ER PT B AU Craig, JL Geiselman, EE AF Craig, JL Geiselman, EE GP SAFE SAFE TI Further development of the panoramic night vision goggle SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB A novel approach to significantly increasing the field of view (FOV) of night vision goggles (NVGs) has been developed. This approach uses four image intensifier tubes instead of the usual two to produce a 100 degree wide FOV. A conceptual demonstrator device was fabricated in November 1995 and limited flight evaluations were performed. Further development of this approach continues with eleven advanced technology demonstrators scheduled for delivery by the end of December 1998 that will feature five different design configurations. Some of the units will be earmarked for ejection seat equipped aircraft due to their low profile design allowing the goggle to be retained safely during and after ejection. Other deliverables will be more traditional in design approach and concentrate more on transport and helicopter aircraft as well as ground personnel. Planned resting to collect both subjective and quantitative data will begin in November 1998. C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Craig, JL (reprint author), USAF, Res Lab, Human Effectiveness Directorate, 2255 H St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 26 EP 30 PG 5 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200004 ER PT B AU Task, HL AF Task, HL GP SAFE SAFE TI Chemical lightsticks as a night vision goggle compatible lighting technique for aircraft cockpits: Characteristics, pros and cons SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB Night vision goggles (NVGs) are used for night flying in many military aircraft in the US Army, Navy, and Air Force. NVGs are seen as a means of improving flying safety by providing aircrew with a direct view of the outside world scene thereby improving situation awareness. However, NVGs cannot operate effectively in a cockpit environment unless the interior lighting is NVG compatible. NVG compatible means the lighting is sufficient for the aircrew to view their instruments with their unaided vision but the lighting does not interfere with the NVG's view of the outside world. There are several ways to achieve NVG compatibility by using plastic and glass filters, and by changing light sources to eliminate near infra-red light from the cockpit. One less desirable technique for achieving NVG compatible lighting is to use chemical lightsticks to flood-light the cockpit instrumentation. This paper presents a number of issues associated with using "chemsticks" as a means of achieving NVG compatibility including spectral effects, temporal effects, and temperature effects. It is concluded that chemsticks are marginal as a means of achieving NVG compatibility. Also, if they are used, then pilots and associated support personnel need to be informed of the chemstick's limitations and characteristics to assure safe NVG flight operations. 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 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 34 EP 38 PG 5 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200006 ER PT B AU Wieck, MTD Quartuccio, J McDonald, AB AF Wieck, MTD Quartuccio, J McDonald, AB GP SAFE SAFE TI Fourth generation escape systems technology demonstration program - Objectives and accomplishments SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB The joint USAF/Navy Fourth Generation Escape Systems Technology Demonstration Program was conducted under USAF contract to develop and demonstrate technologies which will enable the expansion of the aircrew escape envelope beyond that of current, or third, generation escape systems. The areas of the escape envelope in which expansion was demonstrated were for escape at extremely high speed and under low altitude, adverse attitude conditions. The primary technologies which were developed for demonstration were: Controllable propulsion Digital flight controls Advanced life protection features Demonstration tests at adverse attitudes and extremely high speeds produced a low risk of injury previously thought unachievable with an open ejection seat. The Fourth Generation Escape Systems Technology Demonstration Program not only met the objectives, but established the benchmark against which future ejection seat performance will be judged. C1 USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. RP Wieck, MTD (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 115 EP 123 PG 9 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200016 ER PT B AU Lessard, CS AF Lessard, CS GP SAFE SAFE TI Comparison of optokinetic scene effects on the somatogyral illusion SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB The objective of this study was to determine during rotation the relative importance of a scene in achieving "visual dominance" over non-visual vestibular orientation inputs, e.g., otolith and semicircular canals. Five visual scenes were presented, while rotating the subject (at three angular acceleration rates), to obtain the optkinetic reflex (OKR) and/or the vestibule-ocular reflex (VOR) and perception of rotation. The onset time and direction of rotation, as well as EOG and chair velocity were recorded. Adaptation times during rotation at constant angular velocity and during post-rotation were also recorded. Analysis of perceived times (onset, adaptation, and post-rotatory adaptation) with the EOG slow-phase velocity at respectively perceived times were analyzed using the SAS procedures Analysis of Variance (ANOVA) and General Linear Models (GLM). Basic hypotheses for the study were: "There are no differences in latencies for either onset time (L1), adaptation to rotation (L2), or adaptation to post rotatory motion (L4), between treatment conditions, or between Groups of subjects, or between acceleration rates, between constant rotation velocities, or between direction of rotation." From the results, it was concluded that pilots are highly visually dependent; additionally, if there is a sensory conflict, a larger percentage of individuals (pilots) will follow visual perceptions even if the perception is incorrect. However, in sensory conflict conditions, with degraded visual scene individuals including pilots will revert to vestibular perception rather than visual perception (less visually coupled), approaching percentages as noted with a dark environment. C1 USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 216 EP 231 PG 16 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200025 ER PT B AU Zehner, GF Dixon, DA Files, PS AF Zehner, GF Dixon, DA Files, PS GP SAFE SAFE TI A multi-media training system for measuring anthropometric accommodation in cockpits SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB This presentation describes and demonstrates a multi-media training system being developed at the Air Force Research Laboratory. This system uses narration, photos, video, and animation to teach potential users how anthropometric accommodation is assessed. C1 USAF, Res Lab, Human Interface Directorate, Wright Patterson AFB, OH 45433 USA. RP Zehner, GF (reprint author), USAF, Res Lab, Human Interface Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 258 EP 262 PG 5 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200030 ER PT B AU Chelette, TL Tripp, LD Frazier, JW AF Chelette, TL Tripp, LD Frazier, JW GP SAFE SAFE TI Female performance in the high G environment: An overview of centrifuge research 1996-1997 SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Chelette, TL (reprint author), USAF, Res Lab, AFRL HEPA Bldg,2800 Q St, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 353 EP 360 PG 8 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200039 ER PT B AU Buhrman, JR Andries, MJ Ma, D AF Buhrman, JR Andries, MJ Ma, D GP SAFE SAFE TI Rise factors in ejection seat design associated with upward ejection for a large occupant SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB During ejection tower tests conducted by Martin-Baker with a Large JPATS manikin in a simulated Martin-Baker ejection seat (MKUS16LA), the manikin's pelvic region rotated forward under the lap belt and partially out of the seat. This could have serious implications for human occupants due to the potential for spinal misalignment and altered trajectory during ejection. A series of simulated ejections using a biodynamic computer model showed that this phenomenon was due in large part to the inertial properties of the large manikin in combination with the seat pan length and initial leg position. A series of +Gz impact tests on a vertical deceleration tower with the Large JPATS manikin were conducted to verify and more precisely quantify the model results. The tests demonstrated large lap belt loads and excessive hip and knee displacements in the manikin, and identified several contributing factors in the seat/restraint system, including the pre-impact positioning of the manikin's thighs above the seat pan, the length of the seat pan, and the fabric of the flight suit. Modifications were implemented which lowered the initial leg position and extended the seat pan length. Modifications to the manikin which altered the weight and center of mass of the legs were also made in order to more accurately reflect the mean anthropometry characteristics of the large male crewmember. It was found that the seat length and leg positioning modifications when used in combination with the modified manikin were successful in reducing both the loads and displacements. C1 USAF, Accelerat Effects & Escape Branch, HEPA, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Buhrman, JR (reprint author), USAF, Accelerat Effects & Escape Branch, HEPA, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 361 EP 370 PG 10 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200040 ER PT B AU Webb, JT Pilmanis, AA AF Webb, JT Pilmanis, AA GP SAFE SAFE TI Preoxygenation time versus decompression sickness incidence SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB Preoxygenation, breathing 100% oxygen prior to decompression, has been used for well over half of this century to reduce decompression sickness (DCS) incidence. Duration of preoxygenation has been reported to be inversely related to subsequent DCS incidence. A direct comparison of DCS incidence at 30,000 ft versus preoxygenation time is needed to allow better-informed decisions regarding the cost vs. benefit of increasing preoxygenation time to prevent DCS. To obtain such a comparison, we accomplished a retrospective study of exposures to 30,000 ft (226 mm Hg; 4.37 psia) while performing mild exercise. The 86 male exposures were preceeded by preoxygenation times of one to four h. Venous gas emboli (VGE) and DCS symptom development were monitored and recorded. Although more protection was demonstrated with increasing preoxygenation time, the cost-to-benefit ratio also increases with each additional increment of preoxygenation time. The diminishing return of increasing preoxygenation to reduce DCS would eventually impact mission planning and crew duty limitations. Alteration in the physiology of denitrogenation, such as inclusion of exercise during preoxygenation, may provide better and more cost-effective DCS protection than simply increasing preoxygenation time. C1 USAF, Res Lab, Wyle Labs, Life Sci Syst & Serv, Brooks AFB, TX 78235 USA. RP Webb, JT (reprint author), USAF, Res Lab, Wyle Labs, Life Sci Syst & Serv, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 419 EP 424 PG 6 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200045 ER PT B AU Albery, WB AF Albery, WB GP SAFE SAFE TI Human centrifuges: The old and the new SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB The human centrifuge has been around for many years. Some of the earliest known uses were for medical treatment. More recently, since aviation was born in 1903, the centrifuge has been used to emulate aircraft and reproduce sustained accelerations greater than I G on the ground. The advantage a human centrifuge provides over an aircraft that can pull G is that it is I) ground-based; thus safe, and 2) capable of providing exact G profiles. In this paper I will look at the history of the human centrifuge, with emphasis on the latest additions to the inventories of France, Sweden, and the UK. These new, devices represent a "Fourth Generation" of centrifuges. I will also discuss the issue of G onset rate of these devices and the 15 G/sec onset rate being ordered for modern, flyable, human centrifuges. C1 USAF, Res Lab, Accelerat Effects & Escape Branch, Flight Stress Protect Div,Human Effectiveness Dir, Wright Patterson AFB, OH 45433 USA. RP Albery, WB (reprint author), USAF, Res Lab, Accelerat Effects & Escape Branch, Flight Stress Protect Div,Human Effectiveness Dir, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 434 EP 445 PG 12 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200047 ER PT B AU Allnutt, RA Tripp, LD AF Allnutt, RA Tripp, LD GP SAFE SAFE TI Color hue shift during gradual onset Gz acceleration SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB Introduction: Color Displays will become prevalent in future cockpits. This study focuses on subjective reporting of color perception during relaxed, gradual onset, Gz acceleration. Methods: 12 male and 5 female subjects participated in this study. Four separate color displays were used in this experiment. The first was a pinwheel rainbow color display similar to one used in altitude chamber training. The second display was a series of vertical color bars. The colors in these two displays were dark blue, light blue, white, lime green, purple, and yellow. The third display included two or three of these colors presented as colored circles on a light. bar against different background colors. The fourth display was a digitized PAA sectional chart. The Dynamic Environment Simulator (DES) centrifuge was used to generate a 0.1 Gz per second onset rate. The subjects remained relaxed until they had central light loss, at which time they strained. Results: In all four of the display conditions, subjects reported sequential changes in color perception. The first hue shift was a disappearance of light blue into white. The second shift was green to yellow. Finally, a blending of all four of these colors into white was reported. C1 USAF, Res Lab, Human Effectiveness Div, Wright Patterson AFB, OH 45433 USA. RP Allnutt, RA (reprint author), USAF, Res Lab, Human Effectiveness Div, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 446 EP 453 PG 8 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200048 ER PT B AU Self, BP White, C Diesel, DA Whitestone, J AF Self, BP White, C Diesel, DA Whitestone, J GP SAFE SAFE TI Development of an extra small narrow MBU-20/P oxygen mask SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc C1 USAF, Res Lab, Syst Res Branch, Brooks AFB, TX 78235 USA. RP Self, BP (reprint author), USAF, Res Lab, Syst Res Branch, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 466 EP 472 PG 7 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200050 ER PT B AU Pint, S Perry, C Plaga, J AF Pint, S Perry, C Plaga, J GP SAFE SAFE TI Investigation of occupant restraint improvements to the UPCo SIIIS-3 ejection seat SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc AB During the Front Line Ejection Equipment Tests (FLEET) program, higher than anticipated radical values were recorded using the 103 Ib Lightest Occupant In Service (LOIS) manikin ejecting in the SIIIS-3 ejection seat with an F-15 forebody. The radical value, an injury potential indicator, is calculated using the seat acceleration in the x and y axes, and the Dynamic Response (DR) in the z mis. It was observed that the LOIS manikin was poorly restrained in the seat regardless of the tension applied to the harness straps. Three concepts have been identified that can be readily incorporated into the seat to improve occupant restraint. These concepts are. an improved seat cushion using a conforming material, inertia reel rollers that are fixed with respect to the headbox, and inflatable elements attached to the lap belt as space fillers. Tests with manikins were performed to evaluate the proposed improvements. The large ADAM (218 Ib) manikin and the LOIS manikin were subjected to impacts along the +z, -x and +y mes using the AFRL Vertical Deceleration Tower (VDT) and Horizontal Impulse Accelerator (HLA). Tests were conducted with the original seat configuration and with the proposed Improvements incorporated into the seat. Manikin response characteristics were measured and results were compared to evaluate the effectiveness of the modifications to the SIIIS ejection seat. Overall, the results for the study were inconclusive. The new seat improved the response of the LOIS manikin in the x and y axes, but degraded the response in the z axis. The new seat showed very little effect on the response of the large ADAM. C1 USAF, Res Lab, Human Effectiveness Directorate, Crew Survivabil & Logist Div, Wright Patterson AFB, OH 45433 USA. RP Pint, S (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Crew Survivabil & Logist Div, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 482 EP 491 PG 10 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200052 ER PT B AU Sventek, JCS Shaffstall, RM AF Sventek, JCS Shaffstall, RM GP SAFE SAFE TI Re-engineering usaf aerospace physiology SO THIRTY-SIXTH ANNUAL SYMPOSIUM SAFE ASSOCIATION, PROCEEDINGS LA English DT Proceedings Paper CT 36th Annual SAFE Symposium CY SEP 14-16, 1998 CL PHOENIX, AZ SP SAFE Assoc C1 USAF, Med Operat Agcy, Off Surg Gen, Bolling AFB, DC USA. RP Sventek, JCS (reprint author), USAF, Med Operat Agcy, Off Surg Gen, Bolling AFB, DC USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SAFE ASSOC PI YONCALLA PA 4995 SCOTTS VALLEY RD, PO BOX 490, YONCALLA, OR 97499-0490 USA PY 1998 BP 575 EP 576 PG 2 WC Engineering, Aerospace SC Engineering GA BL94R UT WOS:000077255200061 ER EF