FN Thomson Reuters Web of Science™ VR 1.0 PT S AU Geiselman, EE Post, DL AF Geiselman, EE Post, DL BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Helmet-mounted display targeting symbology color coding: An air-to-air scenario evaluation SO HELMET- AND HEAD-MOUNTED DISPLAYS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet-Mounted and Head-Mounted Displays IV Conference CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE air-to-air; airborne; coding; color; combat; display; helmet; HMD; symbology; targeting AB Laboratory and flight test evaluations have consistently demonstrated the potential for helmet-mounted display (HMD) presented information to enhance air combat performance. The Air Force Research Laboratory's (AFRL's) Helmet-Mounted Sight Plus (HMS+) program seeks to provide further enhancement by enabling the presentation of multi-color symbology and sensor imagery. To take proper advantage of color-capable HMDs, systematic evaluations must be conducted to identify the best color-coding techniques. The experiment described here is the second we have conducted to address this need. The first experiment identified the better of two competing color coding strategies for air-to-air weapons symbology and indicated that pilots preferred the color codes over an otherwise equivalent monochrome baseline. The present experiment compared the "winning" color code to the monochrome baseline during trials of a complex multi-player air-to-air weapon delivery scenario. Twelve fighter pilots representing three different countries (U.S., U.K., and Sweden) flew simulator trials that included target identification, intercept, attack, missile launch, and defensive maneuvering tasks. Participants' subjective feedback and performance data indicated a preference for color coded symbology. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Geiselman, EE (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 14 TC 1 Z9 1 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3163-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3689 BP 66 EP 75 DI 10.1117/12.352846 PG 10 WC Engineering, Aerospace; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BN52E UT WOS:000082111800007 ER PT S AU Jackson, TW Craig, JL AF Jackson, TW Craig, JL BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Design, development, fabrication, and safety-of-flight testing of a panoramic night vision goggle SO HELMET- AND HEAD-MOUNTED DISPLAYS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet-Mounted and Head-Mounted Displays IV Conference CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE night vision goggle; helmet-mounted display; image intensification; field of view; night operations; head-up display; safety-of-flight; flight safety; windblast testing; aircraft ejection ID ADVANCED FIGHTER HELMETS; EJECTION 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 delivered in March 1999 that 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 lends itself to transport and helicopter aircraft as well as ground personnel. Extensive safety-of-flight testing has been accomplished as a precursor to the F-15C operational utility evaluation flight testing at Nellis AFB that began in March 1999. C1 USAF, Res Lab, Human Effectiveness Directorate, HECV, Wright Patterson AFB, OH 45433 USA. RP Jackson, TW (reprint author), USAF, Res Lab, Human Effectiveness Directorate, HECV, 2255 H St, Wright Patterson AFB, OH 45433 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 0-8194-3163-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3689 BP 98 EP 109 DI 10.1117/12.352819 PG 12 WC Engineering, Aerospace; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BN52E UT WOS:000082111800010 ER PT S AU Marticello, DN Spillman, MS AF Marticello, DN Spillman, MS BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Joint Helmet-Mounted Cueing System accuracy testing using celestial references SO HELMET- AND HEAD-MOUNTED DISPLAYS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet-Mounted and Head-Mounted Displays IV Conference CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE helmet-mounted sight; helmet-mounted display; head tracker; line-of-sight accuracy AB The Joint Helmet-Mounted Cueing System (JHMCS) incorporates a man-mounted, ejection-compatible helmet-mounted display system, with the capability to cue and verify cueing of high off-axis sensors and weapons, on U.S. Air Force and U.S. Navy single-seat and two-seat fighter aircraft. Program requirements call for the JHMCS to meet a certain level of pointing accuracy. Pointing accuracy is defined as how close the JHMCS computed line of sight (LOS) is to the actual LOS of the pilot. In order to test the pointing accuracy of JHMCS throughout the pilot's range of motion, truth data had to be established at various azimuths and elevations. Surveyed ground locations do not provide the ability to test at different helmet elevations. Airborne targets do not provide the measurement precision needed to validate system accuracy. Therefore, celestial bodies (stars), whose locations are precisely known for a given time and date at a specific location, will serve as truth data for LOS accuracy testing. This paper addresses the theory, planning, and status of JHMCS accuracy testing utilizing celestial bodies as reference points. C1 USAF, 445th Flight Test Squadron, Edwards AFB, CA 93523 USA. RP Marticello, DN (reprint author), USAF, 445th Flight Test Squadron, Edwards AFB, CA 93523 USA. NR 3 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 0-8194-3163-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3689 BP 126 EP 134 PG 9 WC Engineering, Aerospace; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BN52E UT WOS:000082111800013 ER PT S AU Barnaba, JM Kirk, WF AF Barnaba, JM Kirk, WF BE Lewandowski, RJ Haworth, LA Girolamo, HJ TI Evaluation of ejection safety for the joint helmet mounted cueing system SO HELMET- AND HEAD-MOUNTED DISPLAYS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Helmet-Mounted and Head-Mounted Displays IV Conference CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE helmet mounted display (HMD); ejection safety; JHMCS; windblast testing; ejection testing; tower testing; human factors AB Aircrew safety is paramount in the design of a helmet-mounted display (HMD). For the tactical aircrew, ensuring a successful ejection presents significant design challenges. The Joint Helmet Mounted Cueing System (JHMCS) Integrated Product Team (IPT) has been evaluating Vision Systems International's HMD design for aircrew protection in this environment. The JHMCS IPT has developed a set of test objectives in concert with acquisition reform to demonstrate ejection compatibility of the JHMCS. This testing series will be discussed, and will include windblast, ejection tower, and sled and in-flight ejection testing, findings and design impacts. JHMCS performance parameters evaluated include structural integrity, facial and head protection, neck tensile loads, ejection seat and crew equipment compatibility, and mechanical functionality. The design environment for the JHMCS currently is both small and large, male and female aircrew withstanding a successful 450-knot ejection in any of four current USAF & USN tactical aircraft platforms. C1 Aeronaut Syst Ctr, Joint Helmet Mounted Cueing Syst Program Off, SMH, Wright Patterson AFB, OH 45433 USA. RP Barnaba, JM (reprint author), Aeronaut Syst Ctr, Joint Helmet Mounted Cueing Syst Program Off, SMH, MS28,2145 Monahan Way, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3163-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3689 BP 210 EP 219 DI 10.1117/12.352833 PG 10 WC Engineering, Aerospace; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BN52E UT WOS:000082111800023 ER PT S AU Arman, MJ AF Arman, MJ BE Phillips, RM TI High efficiency long pulse gigawatt sources of HPM radiation SO HIGH ENERGY DENSITY MICROWAVES SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT Conference on High Energy Density Microwaves CY OCT, 1998 CL PAJARO DUNES, CA AB The High Power Microwave (HPM) technology has advanced tremendously in the last five decades. What started out as a mere passive tool in the form of radar for detecting airborne objects during the second world war, has grown to be an active vehicle that can influence and impact its target. Progress has been made in all fronts. The peak radiated power has gone up several orders of magnitude to several gigawatts, the efficiency has grown by a wide margin, and the total energy radiated for pulsed sources has grown to several hundreds of Jules per pulse. Major obstacles still exist. The number of sources that have already achieved one gigawatt or higher is too great to cover here. In what follows, we will briefly describe the sources that have radiated one gigawatt or higher with a pulselength of 300 ns or longer, and an rms efficiency of 10% or higher. We also address the obstacles lying ahead and suggest possible means of overcoming them. The sources presented are the Relativistic Klystron Oscillator (RKO), the Magnetically insulated Line Oscillator (MILO), and the Tapered Magnetically Insulated Line Oscillator (TMILO). C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Arman, MJ (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 3 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 1-56396-796-0 J9 AIP CONF PROC PY 1999 VL 474 BP 342 EP 346 DI 10.1063/1.59022 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Particles & Fields SC Engineering; Physics GA BN13E UT WOS:000080797900036 ER PT B AU Wu, S AF Wu, S BE Reinhardt, HW Naaman, AE TI Active fiber composites SO HIGH PERFORMANCE FIBER REINFORCED CEMENT COMPOSITES (HPFRCC3) SE RILEM PROCEEDINGS LA English DT Proceedings Paper CT 3rd International Workshop on High Performance Fiber Reinforced Cement Composites (HPFRCC3) CY MAY 16-19, 1999 CL MAINZ, GERMANY SP RILEM, ACI, ACBM, Univ Michigan, Univ Stuttgart AB Recently new actuation materials have greatly advanced the performance of smart structures. Active fiber composite is one major recent development. This paper is to present the development of the active fiber composites using piezoelectric fibers. The characterization and modeling research in the electro-mechanical coupling field will be discussed. The current development emphases to increase performance, lower cost and optimize the system design are also described. Opportunities do exist for low cost robust materials to be used in the future smart composite systems. C1 USAF, Bolling AFB, Off Sci Res, Washington, DC 20204 USA. RP Wu, S (reprint author), USAF, Bolling AFB, Off Sci Res, Washington, DC 20204 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU R I L E M PUBLICATIONS PI BAGNEUX PA 157 RUE DES BLAINS, 92220 BAGNEUX, FRANCE BN 2-912143-06-3 J9 RILEM PROC PY 1999 VL 6 BP 153 EP 157 PG 5 WC Construction & Building Technology; Engineering, Civil; Materials Science, Composites SC Construction & Building Technology; Engineering; Materials Science GA BS09H UT WOS:000168606300014 ER PT B AU Keil, SL Balasubramaniam, KS Milano, LJ Bayliss, A Jones, J Clark, J AF Keil, SL Balasubramaniam, KS Milano, LJ Bayliss, A Jones, J Clark, J BE Rimmele, TR Balasubramaniam, KS Radick, RR TI Dynamical motions as precursors to activity SO HIGH RESOLUTION SOLAR PHYSICS: THEORY, OBSERVATIONS, AND TECHNIQUES SE ASTRONOMICAL SOCIETY OF THE PACIFIC CONFERENCE SERIES LA English DT Proceedings Paper CT 19th NSO/SP International Workshop on High Resolution Solar Physics - Theory Observations and Techniques CY SEP 28-OCT 02, 1998 CL SUNSPOT, NM SP Natl Solar Observ, Natl Opt Astron Observ, NSF, Div Astron & Atmospher Sci, NASA, Off Space Sci, USAF, Off Sci Res, European Off Aerosp Res & Dev, Asian Off Aerosp Res & Dev, USAF, Res Labs, Space Hazards Branch ID X-RAY JETS; EMERGING FLUX; FLARES; COMPLEX; FLOWS AB We have observed the evolution of several active regions prior to flares, H alpha brightening, and CMEs. The observations include full-disk H alpha images taken at a 10 second cadence with the NSO/SP flare patrol and high-resolution images of the selected active regions taken with the NSO/SP Dunn Solar Telescope. The high-resolution data includes 30 second cadence Doppler-grams and magnetograms and 5 second cadence H alpha and G-band images. Using local correlation tracking techniques, we derive horizontal surface flows reflecting photospheric and chromospheric heights. These are compared with the line-of-sight magnetic flux and velocity field and with structures seen in the H alpha and G-band images. We investigate these data for pre-activity signatures. Our preliminary analysis of flares on 1997 April 7 and 1998 May 5 indicates that strong vortices in the surface flow often precede strong H alpha brightening and filament eruptions. The full-disk H alpha campaigns are being conducted to develop activity prediction techniques in anticipation of the high cadence imaging that will be provided by the air Force's Improved Observing Optical Network (ISOON). C1 USAF, Res Lab, Space Hazards Branch, Sunspot, NM 88349 USA. RP Keil, SL (reprint author), USAF, Res Lab, Space Hazards Branch, Sunspot, NM 88349 USA. NR 13 TC 4 Z9 4 U1 0 U2 0 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 USA BN 1-58381-009-9 J9 ASTR SOC P PY 1999 VL 183 BP 540 EP 550 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN98Q UT WOS:000083761400065 ER PT S AU Restaino, SR Dayton, D Baker, JT AF Restaino, SR Dayton, D Baker, JT BE Gonglewski, JD Vorontsov, MA TI Dual frequency nematic devices for wavefront control: Preliminary results SO HIGH-RESOLUTION WAVEFRONT CONTROL: METHODS, DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Resolution Wavefront Control - Methods, Devices, and Applications CY JUL 19-20, 1999 CL DENVER, CO SP SPIE ID CRYSTAL AB The use of liquid crystal devices for wavefront control has been suggested and implemented by several authors. Our group has been at the forefront of the development of this technology. In this paper we report some preliminary experimental results on the use of Nematic based liquid crystal devices. Several experimental efforts have been carried out in the past few months. One of the main aims was to characterize a new devices that uses dual frequency nematic material. C1 USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 USA. RP Restaino, SR (reprint author), USAF, Res Lab, DEBS, 3550 Aberdeen SE, Kirtland AFB, NM 87117 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3246-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3760 BP 34 EP 38 DI 10.1117/12.367600 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BP45X UT WOS:000085205600004 ER PT S AU Gruneisen, MT Martinez, T Wick, DV Wilkes, JM Baker, JT Percheron, I AF Gruneisen, MT Martinez, T Wick, DV Wilkes, JM Baker, JT Percheron, I BE Gonglewski, JD Vorontsov, MA TI Holographic compensation of severe dynamic aberrations in membrane-minor based telescope systems SO HIGH-RESOLUTION WAVEFRONT CONTROL: METHODS, DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Resolution Wavefront Control - Methods, Devices, and Applications CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE aberration compensation; spatial light modulators; holographic recording materials; and adaptive optics AB "Real-time holography compensates for severe aberrations in membrane-mirror based telescope systems. Laboratory demonstrations in both imaging and beam projection have been conducted Prototype optically addressed liquid-crystal spatial light modulator devices, developed and adapted for this application, are demonstrated with significantly improved diffraction efficiencies." C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Gruneisen, MT (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 12 TC 22 Z9 22 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 0-8194-3246-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3760 BP 142 EP 152 DI 10.1117/12.367589 PG 11 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BP45X UT WOS:000085205600018 ER PT S AU Marker, DK Rotge, JR Carreras, RA AF Marker, DK Rotge, JR Carreras, RA BE Gonglewski, JD Vorontsov, MA TI Summary: optical membrane workshop SO HIGH-RESOLUTION WAVEFRONT CONTROL: METHODS, DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Resolution Wavefront Control - Methods, Devices, and Applications CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE membrane optics; optical quality reflectors; thin films; reflectors; inflatables; solar collectors; optical quality membranes AB Thin flexible membranes with curvature are gaining favor as lightweight optical components. The Surveillance Technologies Branch of the Air Force Research Laboratory has demonstrated that membranes can yield a near diffraction limited image when combined with real-time holography as the wavefront correction method.(1,2) Researchers at the University of Strathclyde in Glasgow, Scotland are using large membrane mirrors in a volumetric imaging project, while others at the Vavilov Laser Physics Institute in Saint Petersburg, Russia are investigating the use of real-time holography to correct membrane mirror aberrations. Existing membranes, however, have not been designed with optical imaging as the intended application. Thus, there is a need to design and construct optical quality membranes. This report summarizes the proceedings of a workshop sponsored by the Surveillance Technology Branch of the Air Force Research Laboratory held October 7 - 8? 1998 in Baltimore, Maryland, convened to gain a better understanding of this process. C1 USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, Kirtland AFB, NM 87117 USA. RP Marker, DK (reprint author), USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, 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 0-8194-3246-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3760 BP 192 EP 194 DI 10.1117/12.367599 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BP45X UT WOS:000085205600023 ER PT S AU Wilkes, JM Jenkins, CH Marker, DK Carreras, RA Duneman, DC Rotge, JR AF Wilkes, JM Jenkins, CH Marker, DK Carreras, RA Duneman, DC Rotge, JR BE Gonglewski, JD Vorontsov, MA TI Concave membrane mirrors from aspheric to near-parabolic SO HIGH-RESOLUTION WAVEFRONT CONTROL: METHODS, DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Resolution Wavefront Control - Methods, Devices, and Applications CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE membrane optics; optical quality reflectors; thin films; reflectors; inflatables; solar collectors; optical quality membranes AB The surface of an initially planar membrane, which is subsequently subjected to a pressure difference, can be manipulated into a variety of shapes. This report discusses two methods by which optically desirable deterministic shapes might be achieved. The first involves pre-straining of the membrane, a technique which has already been demonstrated(1-3) to reduce the spherical aberration in such a mirror. However, near-parabolic shapes at low f-numbers appear not to be achievable with this method, i.e., using pressure differences and pre-strain alone. The second technique is a somewhat novel one involving the use of a plunger to translate the central region of the membrane along the optical axis. Preliminary results suggest that attainment of a near-parabolic shape over a substantial area of the membrane may indeed be possible with this method. The experiments described here use an aluminum coated 125 micron thick polyimide membrane with a clear aperture of 11 inches. C1 USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, Kirtland AFB, NM 87117 USA. RP Wilkes, JM (reprint author), USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 6 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 0-8194-3246-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3760 BP 213 EP 223 DI 10.1117/12.367593 PG 11 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BP45X UT WOS:000085205600026 ER PT S AU Marker, DK Rotge, JR Carreras, RA Duneman, D Wilkes, JM AF Marker, DK Rotge, JR Carreras, RA Duneman, D Wilkes, JM BE Gonglewski, JD Vorontsov, MA TI Minimum strain requirements for optical membranes SO HIGH-RESOLUTION WAVEFRONT CONTROL: METHODS, DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Resolution Wavefront Control - Methods, Devices, and Applications CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE membrane optics; optical quality reflectors; thin films; reflectors; inflatables; solar collectors; optical quality membranes AB Thin membranes inherently require a certain minimum amount of strain to adequately perform as optical elements. This minimum strain can be established by simultaneously considering the effects of strain on the reflective surface, film thickness variations, and the corrective range of the adaptive optics (AO) scheme. To show how strain and the optimal optical surface are related, 75 and 125-micron thick polyimide films were examined under various strain conditions. Thickness variations were also mapped and correlated The limits of the AO correction scheme set the films surface topography requirement. Our results will help to partially define an optical quality membrane, which is an important initial step toward the manufacturing of such a film. C1 USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, Kirtland AFB, NM 87117 USA. RP Marker, DK (reprint author), USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 6 TC 4 Z9 4 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3246-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3760 BP 224 EP 231 DI 10.1117/12.367591 PG 8 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BP45X UT WOS:000085205600027 ER PT S AU Carreras, RA Marker, DK Rotge, JR Wilkes, JM Duneman, D AF Carreras, RA Marker, DK Rotge, JR Wilkes, JM Duneman, D BE Gonglewski, JD Vorontsov, MA TI Deployable near-net shape membrane optics SO HIGH-RESOLUTION WAVEFRONT CONTROL: METHODS, DEVICES, AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on High-Resolution Wavefront Control - Methods, Devices, and Applications CY JUL 19-20, 1999 CL DENVER, CO SP SPIE AB The Air Force Research Laboratory (AFRL) is developing a large space-based optical membrane telescope. When this research began a little more than three years ago, the conceptual design was based upon a totally inflatable structure. An inflatable structure has been used for space solar power collection and radio-frequency antennas. To place the development of the membrane optical telescope in perspective, a short history of past inflatables will be presented. The totally inflatable lenticular design used in a variety of space-based applications in radio and radar antennae, solar power for propulsion applications and solar shields is of particular interest. Recently, a new version of a membrane telescope has emerged. Thin membranes on the order of 10 to 100 mu m thick will be packaged and deployed without using inflation to maintain the surface figure. The move away from a pure inflatable is driven by several factors, including wavelength-level tolerances required of optical telescopes, even when real-time holography is invoked as the adaptive optics correction technique. issues that led us to de-emphasize an inflatable, lenticular design and concentrate on a near-net shape film using stress coatings and dual boundary edge control are discussed. C1 USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, Kirtland AFB, NM 87117 USA. RP Carreras, RA (reprint author), USAF, Res Lab, Directed Energy Directorate, Adv Opt & Imaging Div, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 12 TC 8 Z9 8 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3246-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3760 BP 232 EP 238 DI 10.1117/12.367597 PG 7 WC Engineering, Electrical & Electronic; Optics; Physics, Condensed Matter SC Engineering; Optics; Physics GA BP45X UT WOS:000085205600028 ER PT S AU Radsick, TC Saruhan, B Schneider, H AF Radsick, TC Saruhan, B Schneider, H BE Niihara, K Nakano, K Sekino, T Yasuda, E TI Damage tolerant oxide ceramics using pure fiber and matrix laminates SO HIGH TEMPERATURE CERAMIC MATRIX COMPOSITES III SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Conference on High Tempurature Ceramic Matrix Composites (HT-CMC 3) CY SEP 06-09, 1998 CL OSAKA, JAPAN SP Ceram Soc Japan, Amer Ceram Soc, European Ceram Soc, Fine Ceram Res Assoc DE oxide; CMC; laminate; damage-tolerant; mullite ID COMPOSITE; INTERFACES; MULLITE AB A fiber-reinforced ceramic composite was developed using matrix-infiltrated and non-infiltrated fiber layers. Processed layers were hot-pressed together resulting in an oxide-fiber (Nexte1720), oxide-matrix (mullite) composite. Matrix slurries were prepared using submicron-sized alpha-Al2O3 powder coated with amorphous SiO2, along with additives to decrease mullite-formation temperature. Room temperature 3-point bend tests were conducted on as-received samples and samples exposed to long-term, high-temperature oxidation. Composites demonstrate both reasonable fracture strength and damage tolerance. The favorable thermo-mechanical behavior can be explained by the composite's laminate-type structure. Matrix-infiltrated fiber layers provide strength but behave in a brittle, quasi-monolithic manner. Non-infiltrated fiber layers connect infiltrated layers, and provide damage tolerance through in-plane crack deflection and crack bridging. Varying matrix-to-fiber ratio allows tailoring of composite properties, trading off strength for damage tolerance. These composites provide damage tolerant behavior in the absence of fiber interface coatings, and when using a matrix which bonds strongly to fibers. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. DLR, Inst Mat Res, German Aerosp Ctr, D-51147 Cologne, Germany. RP Radsick, TC (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU TRANS TECH PUBLICATIONS PI CLAUSTHAL ZELLERFE PA EINERSBERGER BLICK 28, PO BOX 266, W-3392 CLAUSTHAL ZELLERFE, GERMANY SN 1013-9826 BN 0-87849-818-4 J9 KEY ENG MAT PY 1999 VL 164-1 BP 61 EP 65 PG 5 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11H UT WOS:000080750200013 ER PT S AU Zawada, LP Ishikawa, T AF Zawada, LP Ishikawa, T BE Niihara, K Nakano, K Sekino, T Yasuda, E TI Mechanical behavior of a Si-Ti-C-O fiber-bonded ceramic material SO HIGH TEMPERATURE CERAMIC MATRIX COMPOSITES III SE KEY ENGINEERING MATERIALS LA English DT Article; Proceedings Paper CT 3rd International Conference on High Tempurature Ceramic Matrix Composites (HT-CMC 3) CY SEP 06-09, 1998 CL OSAKA, JAPAN SP Ceram Soc Japan, Amer Ceram Soc, European Ceram Soc, Fine Ceram Res Assoc DE tensile; fatigue; intermediate temperature embrittlement; oxidation AB Ceramic fibers of Si-Ti-C-O were heat treated in air to produce an oxide layer on the surface, and then hot pressed to produce a dense body containing a fiber volume fraction of approximately 80%. Longitudinal tensile data was generated at 23 degrees C, 1000 degrees, and 1150 degrees C to characterize the stress-strain behavior. Results revealed that at 1150 degrees C this composite experienced a reduction in strength of 28%. Fatigue tests at 1000 degrees C and 1150 degrees C were conducted to evaluate the high temperature durability of this composite. The fatigue testing revealed that this system had a similar stress run out level for both temperatures, but exhibited evidence of high temperature oxidation and intermediate temperature embrittlement. C1 AFRL, MLLN, Wright Patterson AFB, OH 45433 USA. Ube Ind, Yamaguchi 775, Japan. RP Zawada, LP (reprint author), AFRL, MLLN, Wright Patterson AFB, OH 45433 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU TRANS TECH PUBLICATIONS PI CLAUSTHAL ZELLERFE PA EINERSBERGER BLICK 28, PO BOX 266, W-3392 CLAUSTHAL ZELLERFE, GERMANY SN 1013-9826 BN 0-87849-818-4 J9 KEY ENG MAT PY 1999 VL 164-1 BP 245 EP 248 PG 4 WC Materials Science, Ceramics; Materials Science, Composites SC Materials Science GA BN11H UT WOS:000080750200056 ER PT S AU Thai, S AF Thai, S BE Trout, TJ TI Laser-induced M-state holographic gratings of a hydrated D96N bacteriorhodopsin film SO HOLOGRAPHIC MATERIALS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Holographic Materials V CY JAN 26, 1999 CL SAN JOSE, CA SP SPIE, Soc Imaging Sci & Technol DE bacteriorhodopsin; hydrated D96N; M-type hologram; transient; laser-induced gratings; three-beam technique ID REFRACTIVE-INDEX; WILDTYPE AB A novel three-laser-beam technique that can be used to investigate holographic diffraction characteristics of an M-type and a transient dynamic hologram of a hydrated D96N mutant bacteriorhodopsin (BR) film is described in this paper. The method in both experiments is to build up molar concentrations in the M-state before holographic gratings are written. Note that the commonality between these two holograms is the M-state holographic gratings. Hence, a B-state absorption light source, a 532-nm doubled Nd: YAD laser, pumps BR molecules from the B-state to the excited M-state, then the M-state absorption beam, a 413-nm wavelength from a Krypton ion laser, is used to write holographic gratings in that state. Writing with an M-state absorption laser induces a direct phototransition from the excited M-state to the B-state (ground state). This concept capitalizes on the bilevel BR system, i.e., depleting the ground state with a B-state absorption laser creates molar concentrations in the excited M-state, and vice versa. The reading is done with a 680-nm laser, which is far away from the absorption bands to ensure a negligible erasing effect on the gratings written in the film, resulting a pure phase hologram with high efficiency. The experimental results have shown that response times are in the order of milliseconds, and Bragg diffraction efficiency is close to 7% for this sample. Note that this CW holographic technique is a nondegenerate four-wave mixing. C1 USAF, Res Lab, SNDP, Rome, NY 13441 USA. RP Thai, S (reprint author), USAF, Res Lab, SNDP, 25 Elect Pkwy, Rome, NY 13441 USA. NR 15 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 0-8194-3109-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3638 BP 35 EP 40 DI 10.1117/12.342817 PG 6 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BM86S UT WOS:000079967300006 ER PT J AU Ree, MJ Carretta, TR Earles, JA AF Ree, MJ Carretta, TR Earles, JA TI In validation sometimes two sexes are one too many: A tutorial SO HUMAN PERFORMANCE LA English DT Article ID VALIDITY AB Validation of selection tests or other selection variables is most frequently accomplished through correlation and regression. It is quite common to note that both sexes or two ethnic groups were included in the sample. Sometimes in the combined sex or ethnic groups the correlation of the predictor and criterion may be moderate or large, but within each group the correlation of predictor and criterion is low or teres. This seeming paradox is not a psychological phenomenon, but a consequence of the mathematics of regression and correlation. Examples of this two-group phenomenon are provided and discussed. The problem would seem to require a Within and Between Analysis (WABA), but having only two groups prohibits the use of WABA methodology. A general hierarchical linear models analysis is proposed and demonstrated. C1 USAF, Res Lab, HEJD, Brooks AFB, TX 78235 USA. RP Ree, MJ (reprint author), USAF, Res Lab, HEJD, 7909 Lindbergh Dr, Brooks AFB, TX 78235 USA. NR 17 TC 2 Z9 2 U1 1 U2 4 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 1999 VL 12 IS 1 BP 79 EP 88 DI 10.1207/s15327043hup1201_4 PG 10 WC Psychology, Applied SC Psychology GA 149XX UT WOS:000077633400004 ER PT S AU Suter, BW Stevens, KS Velazquez, SR Nguyen, T AF Suter, BW Stevens, KS Velazquez, SR Nguyen, T GP IEEE IEEE TI Multirate as a hardware paradigm SO ICASSP '99: 1999 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, PROCEEDINGS VOLS I-VI SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 99) CY MAR 15-19, 1999 CL PHOENIX, AZ SP IEEE, IEEE Signal Proc Soc AB Architecture and circuit design are the two most effective means of reducing power in CMOS VLSI. Mathematical manipulations, based on applying ideas from multirate signal processing have been applied to create high performance, low power architectures. To illustrate this approach, two case studies are presented - one concerns the design of a fast Fourier transforms (FFT) device, while the other one is concerned with the design of analog-to-digital converters. C1 USAF, Res Lab, IFGC, Rome, NY 13441 USA. RP Suter, BW (reprint author), USAF, Res Lab, IFGC, 525 Brooks Rd, Rome, NY 13441 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-5041-3 J9 INT CONF ACOUST SPEE PY 1999 BP 1885 EP 1888 DI 10.1109/ICASSP.1999.758291 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Acoustics; Computer Science; Engineering GA BM75N UT WOS:000079690700472 ER PT S AU Slyh, RE Nelson, WT Hansen, EG AF Slyh, RE Nelson, WT Hansen, EG GP IEEE IEEE TI Analysis of mrate, shimmer, jitter, and F-o contour features across stress and speaking style in the SUSAS database SO ICASSP '99: 1999 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, PROCEEDINGS VOLS I-VI SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 99) CY MAR 15-19, 1999 CL PHOENIX, AZ SP IEEE, IEEE Signal Proc Soc AB This paper highlights the results of an investigation of several features across the style classes of the "simulated" portion of the SUSAS database. The features considered here include a recently-introduced measure of speaking rate called mate, measures of shimmer, measures of jitter, and features derived from fundamental frequency (F-0) contours. The F-0 contour features are the means of F-0 and Delta F-0 over the first, middle, and last thirds of the ordered set of voiced frames for each word. Mrate exhibits differences between the Fast, Neutral, and Slow styles and between the Loud, Neutral, and Soft styles. Shimmer and jitter exhibit differences that are similar to those of mrate: however, the shimmer and jitter differences are less consistent than the mate differences across the speakers in the database. Several F-0 contour features exhibit differences between the Angry, Loud, Lombard, and Question styles and most of the other styles. C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Slyh, RE (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 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 SN 1520-6149 BN 0-7803-5041-3 J9 INT CONF ACOUST SPEE PY 1999 BP 2091 EP 2094 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Acoustics; Computer Science; Engineering GA BM75N UT WOS:000079690700526 ER PT S AU Tzannes, AP Brooks, DH AF Tzannes, AP Brooks, DH GP IEEE IEEE TI Detection of point targets in image sequences by hypothesis testing: A temporal test first approach SO ICASSP '99: 1999 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, PROCEEDINGS VOLS I-VI SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 99) CY MAR 15-19, 1999 CL PHOENIX, AZ SP IEEE, IEEE Signal Proc Soc ID FILTERS AB This paper addresses the problem of designing an efficient and effective image sequence processing scheme that will successfully detect very small (point) targets in a cluttered background when both the target and clutter are moving through the image scene. The specific application area was detection of targets such as airplanes in infrared (IR) image sequences of a cloudy sky which have been taken by a stationary camera. In general we assume that targets are typically one to two pixels in extent and move only a fraction of a pixel per frame, are often low amplitude, and are found in scenes which also contain evolving clutter, e.g. clouds. Our algorithm is based on signal processing and detection theory, includes a perfect measurement performance analysis, and can be made computationally efficient compared to other approaches. Thus the algorithm could be applicable to other image sequence processing scenarios, using other acquisition systems besides IR, such as detection of small moving objects or structures in a biomedical or biological imaging scenario or the detection of satellites, meteors or other celestial bodies in night sky imagery acquired using a telescope. We present a GLRT solution, perfect measurement analysis including ROC curves, and results using real-world infrared data. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Tzannes, AP (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 14 TC 0 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-5041-3 J9 INT CONF ACOUST SPEE PY 1999 BP 3377 EP 3380 DI 10.1109/ICASSP.1999.757566 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Acoustics; Computer Science; Engineering GA BM75N UT WOS:000079690700847 ER PT S AU Wright, CHG Welch, TB Gomes, WJ AF Wright, CHG Welch, TB Gomes, WJ GP IEEE IEEE TI Teaching DSP concepts using MATLAB and the TMS320C31 DSK SO ICASSP '99: 1999 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, PROCEEDINGS VOLS I-VI SE International Conference on Acoustics Speech and Signal Processing (ICASSP) LA English DT Proceedings Paper CT IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 99) CY MAR 15-19, 1999 CL PHOENIX, AZ SP IEEE, IEEE Signal Proc Soc AB A graphically-oriented MATLAB program written by the authors facilitates teaching real-world digital signal processing concepts such as quantization of digital filter coefficients that occur in fixed-point processors, for example the widely used TMS320C5x. While many universities have or plan to buy the inexpensive floating-point TMS320C31 DSKs for pedagogical reasons, this MATLAB program simulates certain fixed-point effects on these Boating-point devices and eliminates the need to purchase expensive specialized software programs or extra hardware. The program described in this paper provides an interactive graphical user interface which communicates directly with the DSK, and demonstrates in real-time how coefficient quantization adversely affects filter performance, without the need for tedious programming of the TMS320C31. 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 13 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1520-6149 BN 0-7803-5041-3 J9 INT CONF ACOUST SPEE PY 1999 BP 3573 EP 3576 DI 10.1109/ICASSP.1999.757615 PG 4 WC Acoustics; Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Acoustics; Computer Science; Engineering GA BM75N UT WOS:000079690700896 ER PT B AU Dale, GA Baust, HD Clinehens, GA AF Dale, GA Baust, HD Clinehens, GA GP IEEE IEEE IEEE TI Implementing pressure-sensitive paint in the AFRL subsonic aerodynamic research laboratory SO ICIASF'99: INTERNATIONAL CONGRESS ON INSTRUMENTATION IN AEROSPACE SIMULATION FACILITIES, RECORD LA English DT Proceedings Paper CT 18th International Congress on Instrumentation in Aerospace Simulation Facilities (ICIASF'99) CY JUN 14-17, 1999 CL TOULOUSE, FRANCE SP Onera-Ctr, Inst Elect & Electr Engineers, European Off Aerosp Res & Dev, Delegat Gen Armement, Conseil Reg Midi-Pyrenees, Mairie Toulouse, Co Presenting Instrument Syst AB Research and development conducted to enable pressure sensitive paint (PSP) measurements to be made in the Air Force Research Laboratory (AFRL) Subsonic Aerodynamic Research Laboratory (SARL) is described. In addition to the fundamental challenges of making PSP measurements in low speed flows, the unique characteristics of the SARL, and how they further challenge the technique, are presented. The design and performance specifications of ultrastable illumination sources, based on arrays of blue light emitting diodes, are given. The characteristics of sol-gel-based PSPs, which offer a number of advantages for low speed measurements, are provided. A highly adaptable system for rigidly mounting and easily positioning and aiming the lamps and camera is described. A process whereby as many as four regions of interest, in the camera field of view, are displayed real-time for monitoring model thermal stability and facility ambient light contamination is shown. Other operational aspects of deploying PSP in SARL, are also described. C1 USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. RP Dale, GA (reprint author), USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5716-7 PY 1999 BP 201 EP 208 DI 10.1109/ICIASF.1999.827160 PG 8 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ47C UT WOS:000088436500020 ER PT B AU Williams, WD Smith, MS Heltsley, FL Brasier, CW Sherrouse, PM Ruyten, WM Price, LL Felderman, EJ Stephens, KM AF Williams, WD Smith, MS Heltsley, FL Brasier, CW Sherrouse, PM Ruyten, WM Price, LL Felderman, EJ Stephens, KM GP IEEE IEEE IEEE TI Non-intrusive diagnostics for the AEDC impulse facility: Applications and results SO ICIASF'99: INTERNATIONAL CONGRESS ON INSTRUMENTATION IN AEROSPACE SIMULATION FACILITIES, RECORD LA English DT Proceedings Paper CT 18th International Congress on Instrumentation in Aerospace Simulation Facilities (ICIASF'99) CY JUN 14-17, 1999 CL TOULOUSE, FRANCE SP Onera-Ctr, Inst Elect & Electr Engineers, European Off Aerosp Res & Dev, Delegat Gen Armement, Conseil Reg Midi-Pyrenees, Mairie Toulouse, Co Presenting Instrument Syst ID FLUORESCENCE AB As part of a modernization of the AEDC hypersonic test capability, a free-piston shock tunnel known as the Impulse Facility, was constructed. Initial shakedown and calibration tests were completed in 1994. The facility remained dormant until the recent resurgence in interest in hypersonics at AEDC. A cooperative project was established between AEDC and the DLR/HEG with the objectives of accelerating and improving the development cycle for both the Impulse Facility and the HEG. An integral part of this project was an ambitious plan for the use of non-intrusive diagnostics to provide key information about the flow field. This paper is essentially a status report of the efforts to date. C1 Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 USA. RP Williams, WD (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN 37389 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 0-7803-5716-7 PY 1999 BP 411 EP 4110 DI 10.1109/ICIASF.1999.827181 PG 3700 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BQ47C UT WOS:000088436500041 ER PT J AU Koch, K Moore, GT AF Koch, K Moore, GT TI Raman oscillation with intracavity sum-frequency generation SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE nonlinear optics; optical frequency conversion; optical mixers; optical mixing; optical propagation in nonlinear media; Raman lasers ID OPTICAL PARAMETRIC OSCILLATION; AMPLIFICATION; CONVERSION; CRYSTALS AB We use a plane-wave analysis to examine a Raman oscillator containing an intracavity sum-frequency interaction that frequency sums the circulating first-order Stokes radiation with the pump radiation. We find that there is an optimum ratio between the nonlinear coupling in the Raman medium and the nonlinear coupling in the sum-frequency generator. We also find that higher order Stokes radiation should be suppressed with the optimum choice of nonlinear coupling in the sum-frequency interaction. Numerical integration of the equations containing transverse effects predicts a time-averaged power-conversion efficiency of 61.4% for conversion of 532- to 273.5-nm radiation using a CN mode-locked frequency-doubled Nd:YAG laser with Ba(NO2)(3) for the Raman material and CsLiB6O10 (CLBO) for the sum-frequency material. C1 USAF, Solid State Laser & Nonlinear Opt Branch, AFRL, DELO,Res Lab, Kirtland AFB, NM 87117 USA. Univ New Mexico, Ctr Adv Studies, Albuquerque, NM 87131 USA. RP Koch, K (reprint author), USAF, Solid State Laser & Nonlinear Opt Branch, AFRL, DELO,Res Lab, Kirtland AFB, NM 87117 USA. NR 16 TC 5 Z9 5 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD JAN PY 1999 VL 35 IS 1 BP 72 EP 78 DI 10.1109/3.737622 PG 7 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 152EZ UT WOS:000077764400012 ER PT J AU Cowan, WD Lee, MK Welsh, BM Bright, VM Roggemann, MC AF Cowan, WD Lee, MK Welsh, BM Bright, VM Roggemann, MC TI Surface micromachined segmented mirrors for adaptive optics SO IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS LA English DT Article DE adaptive optics; beam steering; deformable mirrors; microelectromechanical systems (MEMS); micromirrors ID MICROELECTROMECHANICAL DEFORMABLE MIRROR; REFRACTIVE LENSLET ARRAY; MICROMIRROR ARRAYS; PERFORMANCE; ACTUATORS AB This paper presents recent results for aberration correction and beam steering experiments using polysilicon surface micromachined piston micromirror arrays. Microfabricated deformable mirrors offer a substantial cost reduction for adaptive optic systems. In addition to the reduced mirror cost, microfabricated mirrors typically require low control voltages (less than 30 V), thus eliminating high-voltage amplifiers. The greatly reduced cost per channel of adaptive optic systems employing microfabricated deformable mirrors promise high-order aberration correction at low cost, Arrays of piston micromirrors with 128 active elements were tested. Mirror elements are on a 203-mu m 12 x 12 square grid (with 16 inactive elements, four in each corner of the array). The overall array size is 2.4 mm square. The arrays were fabricated in a commercially available surface micromachining process. The cost per mirror array in this prototyping process is less than $200, Experimental results are presented for a hybrid correcting element comprised of a lenslet array and piston micromirror array, and for a piston micromirror array only. Also presented is a novel digital deflection micromirror that requires no digital to analog converters, further reducing the cost of adaptive optics systems. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. Michigan Technol Univ, Dept Elect Engn, Houghton, MI 49931 USA. RP Cowan, WD (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 31 TC 35 Z9 37 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1077-260X J9 IEEE J SEL TOP QUANT JI IEEE J. Sel. Top. Quantum Electron. PD JAN-FEB PY 1999 VL 5 IS 1 BP 90 EP 101 DI 10.1109/2944.748110 PG 12 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 190PK UT WOS:000079972900015 ER PT J AU Newell, T Wu, X Gray, AL Dorato, S Lee, H Lester, LF AF Newell, T Wu, X Gray, AL Dorato, S Lee, H Lester, LF TI The effect of increased valence band offset on the operation of 2 mu m GaInAsSb-AlGaAsSb lasers SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE gallium antimonide; quantum-well devices; quantum-well lasers; semiconductor lasers ID QUANTUM-WELL LASERS; POWER; 2.0-MU-M; DIODES AB Two and four quantum-well (QW) GaInAsSb-AlGaAsSb lasers emitting at 2 mu m are reported. In comparison to previously published data, it is found that higher Al content in the QW barrier improves the internal efficiency,saturated modal gain, and characteristic temperature of the lasers, These results are attributed to an increased valence band offset that provides superior hole confinement in the GaInAsSb QW, A differential efficiency of 74% is observed at 25 degrees C under pulsed conditions for a 900-mu m cavity length, 2-QW device, and a record characteristic temperature of 140 K is measured for a 4-QW laser. C1 Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. USA, Res Lab, Adelphi, MD 20783 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. David Sarnoff Res Ctr, Princeton, NJ 08453 USA. RP Newell, T (reprint author), Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. NR 19 TC 27 Z9 28 U1 1 U2 1 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 1999 VL 11 IS 1 BP 30 EP 32 DI 10.1109/68.736380 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 152GR UT WOS:000077768800010 ER PT J AU Yen, GG Kwak, MK AF Yen, GG Kwak, MK TI Dynamic modeling of flexible multibody structures SO IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS LA English DT Article ID EQUATIONS; SYSTEMS; MOTION AB This work is primarily concerned with the development of a mathematical formulation capable of treating the problems of maneuvering and control of flexible multibody structures. The analytical formulation is based upon equations of motion in terms of quasi-coordinates derived for each substructure independently. The individual substructures are made to act as a single structure by means of a consistent kinematical synthesis. in recognition of smaller elastic motions, a perturbation approach is developed whereby the rigid-body maneuvering of the system defines the zero-order kinematical dynamics, while the elastic motions and perturbations from the rigid-body maneuvering define the first-order kinematical synthesis. As a numerical example, the Planar Articulating Controls Experimental (PACE) test article is maneuvered according to a bang-bang control law by means of torque applied to the shoulder and the elbow. The numerical simulation shows a close match with the detailed modal survey. C1 USAF, Phillips Lab, Space Vehicle Technol Div, Kirtland AFB, NM 87117 USA. RP Yen, GG (reprint author), Oklahoma State Univ, Sch Elect & Comp Engn, 202 Engn S, Stillwater, OK 74078 USA. NR 11 TC 2 Z9 2 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9251 J9 IEEE T AERO ELEC SYS JI IEEE Trans. Aerosp. Electron. Syst. PD JAN PY 1999 VL 35 IS 1 BP 148 EP 156 DI 10.1109/7.745688 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 165DE UT WOS:000078503500013 ER PT J AU Sullivan, A Carin, L AF Sullivan, A Carin, L TI Scattering from complex bodies using a combined direct and iterative technique SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE electromagnetic scattering; iterative methods; large bodies; method of moments ID ELECTROMAGNETIC-RADIATION; ARBITRARY SURFACES; REVOLUTION AB An iterative technique is developed for frequency-domain plane wave scattering from electrically large composite bodies. An electric field integral equation (EFIE) formulation is employed in which the submatrices of the moment-method matrix are uncoupled and the current on each geometrically separable region of the composite body is solved independently using a direct method. The currents on the various subcomponents of the body are then recalculated within an outer iterative loop. The technique is applied to the case of a multiwavelength body of revolution (BOR) with two flat-plate attachments. This composite body iterative technique is shown to preserve the simplicity and attractiveness of an isolated BOR while maintaining current continuity across the structure without the use of additional junction currents. This new formulation also allows simple suppression of interior resonance effects normally associated with large closed conducting bodies. C1 USAF, Res Lab, Eglin AFB, FL 32542 USA. Duke Univ, Dept Elect Engn, Durham, NC 27708 USA. RP Sullivan, A (reprint author), USAF, Res Lab, Eglin AFB, FL 32542 USA. NR 19 TC 10 Z9 11 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD JAN PY 1999 VL 47 IS 1 BP 33 EP 39 DI 10.1109/8.752982 PG 7 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 182JH UT WOS:000079495500006 ER PT J AU Hanson, GW Baum, CE AF Hanson, GW Baum, CE TI Asymptotic analysis of the natural system modes of coupled bodies in the large-separation low-frequency regime SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE asymptotic analysis; coupled bodies; natural resonance AB In this paper, we examine the natural system modes (characteristic frequencies and currents) of two coupled bodies in the limit of large separation. It is known that when objects are oriented such that they may interact electromagnetically, natural modes of the coupled system occur. These modes differ from, but may be related to, the natural modes of the isolated bodies. For example, the first antisymmetric and symmetric system frequencies of two identical bodies separated by some intermediate distance spiral around the dominant natural frequency of the isolated body as separation is varied. As separation further increases, these system resonances tend toward the origin in the complex frequency plane, rather than approaching the isolated body-dominant natural frequency. Here we treat an N-body scattering problem in the limit of large separation by replacing the bodies with equivalent dipole moments. The natural frequencies are obtained as singular points in the scattering solution, For the special case of two coupled objects, a simple equation for the natural system frequencies is obtained that shows that the real radian-system frequency approaches the origin as 1/r, independent of the relative orientation and type of the two bodies. The damping coefficient approaches the origin approximately logarithmically as a function of the body orientation and type. Using this formulation, the natural system modes of two coupled wires are investigated for large separation between the wires and compared to an integral equation solution. C1 Univ Wisconsin, Dept Elect Engn & Comp Sci, Milwaukee, WI 53211 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Univ Wisconsin, Dept Elect Engn & Comp Sci, Milwaukee, WI 53211 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-926X EI 1558-2221 J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD JAN PY 1999 VL 47 IS 1 BP 101 EP 111 DI 10.1109/8.753000 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 182JH UT WOS:000079495500015 ER PT J AU Jauchem, JR Frei, MR Ryan, KL Merritt, JH Murphy, MR AF Jauchem, JR Frei, MR Ryan, KL Merritt, JH Murphy, MR TI Lack of effects on heart rate and blood pressure in ketamine-anesthetized rats briefly exposed to ultra-wideband electromagnetic pulses SO IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING LA English DT Article DE blood pressure; cardiovascular system; electromagnetic pulse; heart rate; microwaves; rats; ultra-wideband pulse ID RADIOFREQUENCY RADIATION; LOW-FREQUENCY; MICROWAVE; FIELDS AB Fourteen Sprague-Dawley rats were exposed to pulses produced by a Bournlea ultra-wideband (UWB) pulse generator (rise time, 318-337 ps: maximum E field, 19-21 kV/m), Exposures at a repetition frequency of 1 kHz for 0.5 s or to repetitive pulse trains (2-s exposure periods alternating with 2 s of no exposure, for a total of 2 min) resulted in no significant changes in heart rate or mean arterial blood pressure. These results suggest that acute whole-body exposure to UWB pulses does not here a detrimental effect on the cardiovascular system. C1 USAF, Res Lab, Human Effect Directorate,Directed Energy Div, Radio Frequency Radiat Branch, Brooks AFB, TX 78235 USA. Trinity Univ, Dept Biol, San Antonio, TX 78212 USA. RP Jauchem, JR (reprint author), USAF, Res Lab, Human Effect Directorate,Directed Energy Div, Radio Frequency Radiat Branch, 8315 Hawks Rd, Brooks AFB, TX 78235 USA. EM james.jauchem@aoler.brooks.af.mil NR 20 TC 15 Z9 16 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 0018-9294 J9 IEEE T BIO-MED ENG JI IEEE Trans. Biomed. Eng. PD JAN PY 1999 VL 46 IS 1 BP 117 EP 120 DI 10.1109/10.736767 PG 4 WC Engineering, Biomedical SC Engineering GA 152NA UT WOS:000077782600014 PM 9919833 ER PT J AU Lipton, AE Griffin, MK Ling, AG AF Lipton, AE Griffin, MK Ling, AG TI Microwave transfer model differences in remote sensing of cloud liquid water at low temperatures SO IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING LA English DT Article DE attenuation; clouds; microwave propagation; remote sensing ID SSM/I; VAPOR AB Results from two popular models for the complex permittivity of liquid water were? compared, as applied to radiative transfer computations in the 5-250-GHz range. Substantial differences were found in situations with cloud temperatures below 0 degrees C, Simulations of cloud liquid water retrievals from satellite and ground-based instruments demonstrated that uncertainties in the models at low temperatures can lead to large retrieval errors. C1 USAF, Res Lab, Opt Effect Div, Washington, DC 20330 USA. Radex Inc, Bedford, MA 01730 USA. RP Lipton, AE (reprint author), Atmospher & Environm Res Inc, Cambridge, MA 02139 USA. NR 17 TC 13 Z9 13 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0196-2892 J9 IEEE T GEOSCI REMOTE JI IEEE Trans. Geosci. Remote Sensing PD JAN PY 1999 VL 37 IS 1 BP 620 EP 623 DI 10.1109/36.739129 PN 2 PG 4 WC Geochemistry & Geophysics; Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology SC Geochemistry & Geophysics; Engineering; Remote Sensing; Imaging Science & Photographic Technology GA 158NY UT WOS:000078122700027 ER PT J AU Igelnik, B Pao, YH LeClair, SR Shen, CY AF Igelnik, B Pao, YH LeClair, SR Shen, CY TI The ensemble approach to neural-network learning and generalization SO IEEE TRANSACTIONS ON NEURAL NETWORKS LA English DT Article DE adaptive stochastic optimization; basis functions; ensemble of nets; recursive linear regression ID FUNCTION APPROXIMATION; REGRESSION; BOUNDS AB In this paper a new method is suggested for learning and generalization with a general one-hidden layer feedforward neural network. This scheme encompasses the use of a linear combination of heterogeneous nodes having randomly prescribed parameter values. The learning of the parameters is realized through adaptive stochastic optimization using a generalization data set. The learning of the linear coefficients in the linear combination of nodes is achieved with a linear regression method using data from the training set. One node is learned at a time. The method allows for choosing the proper number of net nodes, and is computationally efficient. The method was tested on mathematical examples and real problems from materials science and technology. C1 Case Western Reserve Univ, Cleveland, OH 44106 USA. AI WARE Inc, Beachwood, OH 44122 USA. Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. China State Shipbldg Co, Res & Dev Acad, Beijing, Peoples R China. RP Igelnik, B (reprint author), Case Western Reserve Univ, Cleveland, OH 44106 USA. NR 40 TC 23 Z9 25 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1045-9227 J9 IEEE T NEURAL NETWOR JI IEEE Trans. Neural Netw. PD JAN PY 1999 VL 10 IS 1 BP 19 EP 30 DI 10.1109/72.737490 PG 12 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 155ZW UT WOS:000077977800004 PM 18252500 ER PT B AU Arnold, DG Sturtz, K Velten, V AF Arnold, DG Sturtz, K Velten, V GP IEEE COMP SOC IEEE COMP SOC TI Invariants of the LWIR thermophysical model SO IEEE WORKSHOP ON COMPUTER VISION BEYOND THE VISIBLE SPECTRUM: METHODS AND APPLICATIONS (CVBVS'99) - PROCEEDINGS LA English DT Proceedings Paper CT IEEE Workshop on Computer Vision Beyond the Visible Spectrum - Methods and Applications (CVBVS 99) CY JUN 22, 1999 CL FT COLLINS, CO SP IEEE, IEEE Comp Soc, Tech Comm Pattern Anal & Machine Intelligence AB The temperature of a surface viewied by a long-wave infrared camera can be predicted by a thermophysical model (a conservation of energy statement at the surface of a unit volume). However this prediction currently requires at least 24 hours of previous imagery in order to estimate the parameters of the model. Absolute invariants, relative invariants, and quasi-invariants provide three possible methods for circumventing this obstacle. Lie group analysis is a fundamental tool for systematically exploring invariance and for finding the appropriate transformations groups. This paper discusses the relevant parts of Lie group analysis and uses them to find the transformation groups and absolute invariants of the thermophysical model. The goal is to recognize objects based upon a Composition of materials that are identified using invariant features of infrared imagery. C1 USAF, Res Lab, Target Recognit Branch, Wright Patterson AFB, OH 45433 USA. RP Arnold, DG (reprint author), USAF, Res Lab, Target Recognit Branch, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 8 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 0-7695-0050-1 PY 1999 BP 49 EP 58 DI 10.1109/CVBVS.1999.781094 PG 10 WC Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Computer Science GA BN32P UT WOS:000081630700006 ER PT B AU Wall, RF Hess, HL AF Wall, RF Hess, HL GP IEEE IEEE TI Induction machines as an alternative for automotive electrical generation and starting systems SO IEMDC'99 - IEEE INTERNATIONAL ELECTRIC MACHINES AND DRIVES CONFERENCE, PROCEEDINGS LA English DT Proceedings Paper CT IEEE International Electric Machines and Drives Conference (IEMDC 99) CY MAY 09-12, 1999 CL SEATTLE, WA SP IEEE, IEEE, Power Engn Soc, IEEE, Ind Applicat Soc AB This paper proposes the induction machine as an alternative to the existing Lundell alternator used around the world. The induction machine has better power to speed characteristics than the current system. It promises increased reliability and economic viability by reduction of mechanical components when integrated with the starter. C1 USAF, Alamogordo, NM 88310 USA. RP Wall, RF (reprint author), USAF, Alamogordo, NM 88310 USA. NR 8 TC 0 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-5293-9 PY 1999 BP 499 EP 501 DI 10.1109/IEMDC.1999.769157 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA BN28R UT WOS:000081429300147 ER PT J AU Lyle, D Chan, Y Head, E AF Lyle, D Chan, Y Head, E TI Improving information-network performance: reliability versus invulnerability SO IIE TRANSACTIONS LA English DT Article ID UNRELIABLE COMPONENTS; STOCHASTIC NETWORK; DISJOINT PRODUCTS; SYSTEM; VULNERABILITY AB As the information revolution continues, those who depend upon secure information-networks but cannot adequately protect them will become more vulnerable to tampering by an adversary. Prescriptive models used to recommend improvements to networks usually use reliability or flow as the Measure Of Effectiveness (MOE). Such measures will not give value to efforts that make a network component more difficult to exploit. Similarly, Risk Assessment Models (RAMs) are used to quantify the importance of a component to overall network performance (again measured in terms of reliability or flow) but do not prescribe improvement strategies. This study develops a prescriptive RAM that includes an MOE called invulnerability. This gives value to efforts that make a component more difficult to exploit. Results show that including the vulnerability MOE as a second criterion to complement the reliability MOE allows one to formulate component-hardening strategies. Furthermore, the Pareto-efficient frontier generated by trading off these two MOEs is very small. This helps to pinpoint specific components that should be improved or hardened for information security. C1 AFMC, DR OAS, Kirtland AFB, NM 87117 USA. USAF, Inst Technol, Dept Operat Sci, Wright Patterson AFB, OH 45433 USA. Natl Secur Agcy, Ft Mead, MD 20755 USA. RP Lyle, D (reprint author), AFMC, DR OAS, Kirtland AFB, NM 87117 USA. NR 32 TC 5 Z9 5 U1 1 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0740-817X J9 IIE TRANS JI IIE Trans. PY 1999 VL 31 IS 9 BP 909 EP 919 DI 10.1080/07408179908969890 PG 11 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 231AF UT WOS:000082283300009 ER PT B AU Rockwell, BA Payne, D Hopkins, RA Hengst, G Toth, C Roach, WP Stolarski, D Noojin, G Thomas, R Cain, C AF Rockwell, BA Payne, D Hopkins, RA Hengst, G Toth, C Roach, WP Stolarski, D Noojin, G Thomas, R Cain, C BE Dennis, J TI Retinal damage mechanisms for ultrashort laser exposure SO ILSC'99: PROCEEDINGS OF THE INTERNATIONAL LASER SAFETY CONFERENCE SE LASER INSTITUTE OF AMERICA - PROCEEDINGS LA English DT Proceedings Paper CT International Laser Safety Conference (ILSC 99) CY MAR 08-11, 1999 CL ORLANDO, FL SP Laser Inst Amer ID PRIMATE EYE; PULSES; THRESHOLD; LESIONS AB The Air Force has led a research effort to investigate the thresholds and mechanisms for retinal damage from ultrashort laser pulses [i.e. nanosecond (10(-9) sec) to femtosecond (10(-15) sec) pulse durations] for the past several years. The outcome is a recommendation for the establishment of maximum permissible exposure limits in the visible and near infrared. We review the progress made in determining trends in retinal damage(1) from laser pulses from one nanosecond to one hundred femtoseconds duration at visible and near-infrared wavelengths including variations in spot size and number of pulses. We discuss the most likely damage mechanisms operative in this pulse width regime and discuss relevance to laser safety. C1 USAF, Res Lab, HEDO, AFRL, Brooks AFB, TX 78235 USA. RP Rockwell, BA (reprint author), USAF, Res Lab, HEDO, AFRL, 8111 18th St, Brooks AFB, TX 78235 USA. RI toth, cynthia/F-5614-2011 NR 20 TC 0 Z9 0 U1 0 U2 0 PU LASER INST AMERICA PI ORLANDO PA 12424 RESEARCH PKWY, STE 130, ORLANDO, FL 32826 USA BN 0-912035-17-4 J9 LIA P PY 1999 VL 4 BP 9 EP 17 PG 9 WC Engineering, Biomedical; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging GA BN49H UT WOS:000082032700002 ER PT B AU Obringer, JW AF Obringer, JW BE Dennis, J TI Genetic induction of cultured human cells by high energy, ultrashort pulse laser-light SO ILSC'99: PROCEEDINGS OF THE INTERNATIONAL LASER SAFETY CONFERENCE SE LASER INSTITUTE OF AMERICA - PROCEEDINGS LA English DT Proceedings Paper CT International Laser Safety Conference (ILSC 99) CY MAR 08-11, 1999 CL ORLANDO, FL SP Laser Inst Amer ID DNA-DAMAGING AGENTS; FOS AB The use of laser light for targeting devices and weapons has sharply increased the likelihood that aircrew and support personnel will be exposed to laser light during operations. The increased potential for exposure of humans highlights the fact that there is a need for scientifically based safety standards for laser exposure at the ultrashort pulse lengths. Current safety standards are largely extrapolations of exposure limits at longer guise lengths using a minimal visible lesion endpoint. in the Rhesus monkey retinal model. A non-animal model for assessing laser-light damage to tissue, particularly human, is quite desirous for obvious scientific, political, and fiduciary reasons. I assessed the sublethal insult to human cells using a tissue culture system Jeer specific genes that have been shown to be important in several biological processes that could lead to cancer or cell death. Using the CAT-Tax (L) (Xenometrix, Inc.) assay, it appears that 1064 nm, picosecond pulses of laser light is sensed and induces several stress response genes including RARE and p-53 in a dose dependent fashion. This approach provides insight into a more global methodology for characterizing environmental stressors via genetic profiling. C1 USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. RP Obringer, JW (reprint author), USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU LASER INST AMERICA PI ORLANDO PA 12424 RESEARCH PKWY, STE 130, ORLANDO, FL 32826 USA BN 0-912035-17-4 J9 LIA P PY 1999 VL 4 BP 27 EP 36 PG 10 WC Engineering, Biomedical; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging GA BN49H UT WOS:000082032700004 ER PT B AU Hengst, G Crockett, G Polhamus, G Kennedy, P Cupello, J Lilius, B Thomas, R Trevino, J Clark, D AF Hengst, G Crockett, G Polhamus, G Kennedy, P Cupello, J Lilius, B Thomas, R Trevino, J Clark, D BE Dennis, J TI Laser range safety tool (LRST) for target reflection analysis SO ILSC'99: PROCEEDINGS OF THE INTERNATIONAL LASER SAFETY CONFERENCE SE LASER INSTITUTE OF AMERICA - PROCEEDINGS LA English DT Proceedings Paper CT International Laser Safety Conference (ILSC 99) CY MAR 08-11, 1999 CL ORLANDO, FL SP Laser Inst Amer ID RISK AB As high energy lasers move from the safe confines of the laboratory into the outdoor domain, additional problems arise in dealing with laser safety. Not only are the nominal ocular hazard distances for direct exposure impractical (on the order of thousands of miles), but now diffuse reflections off targets also have the potential for eye damage out to significant distances. These increased hazard distances are alarming, because it is difficult to contain direct and reflected beam energy on test ranges of limited size. An additional complication is the use of moving targets and, in some cases, moving sources. As a result, a complex series of laser safety calculations is required in order to ensue safe outdoor testing and use of high energy lasers. The Optical Radiation Branch of the U.S. Air Force Research Laboratory is developing new tools and techniques for calculating laser hazard zones. These include a computer model, the Laser Range Safety Tool, which calculates the reflected energy distribution and resulting bio-hazards, produced when high energy lasers impact moving targets. With this tool we expect to support new technology development, while maintaining the highest standards of human safety and environmental compliance. C1 USAF, Res Lab, Opt Radiat Branch, Brooks AFB, TX 78235 USA. RP Hengst, G (reprint author), USAF, Res Lab, Opt Radiat Branch, Brooks AFB, TX 78235 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU LASER INST AMERICA PI ORLANDO PA 12424 RESEARCH PKWY, STE 130, ORLANDO, FL 32826 USA BN 0-912035-17-4 J9 LIA P PY 1999 VL 4 BP 227 EP 235 PG 9 WC Engineering, Biomedical; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Public, Environmental & Occupational Health; Ophthalmology; Radiology, Nuclear Medicine & Medical Imaging GA BN49H UT WOS:000082032700027 ER PT S AU Hollkamp, JJ Gordon, RW AF Hollkamp, JJ Gordon, RW GP SPIE SPIE TI Modal testing of a bladed disk SO IMAC - PROCEEDINGS OF THE 17TH INTERNATIONAL MODAL ANALYSIS CONFERENCE, VOLS I AND II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 17th International Modal Analysis Conference (IMAC) on Modal Analysis - Reducing the Time to Market CY FEB 08-11, 1999 CL KISSIMMEE, FL SP Soc Exptl Mech Inc AB New damping concepts for jet engine blades must be validated by experiment. Ideally, every blade on a bladed disk should be damped in a spin test, it is economically attractive to test only a few damped blades with the remaining blades unaltered. But are the damping values measured with a mix of blades equal to the values measured if all the blades are damped? In a recent study, modal tests were conducted on an 8-bladed model of a jet engine fan with one damped blade to answer this question. The modal tests were challenging because of the high sensitivity of the model to mistuning and the existence of multiple, nearly repeated modal frequencies. The test results were reported in the literature. This paper presents details of the multiinput, multi-output test procedure and modal identification not included in the previous publication. C1 USAF, Res Lab, VASV, Wright Patterson AFB, OH 45433 USA. RP Hollkamp, JJ (reprint author), USAF, Res Lab, VASV, Wright Patterson AFB, OH 45433 USA. NR 7 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 0-912053-64-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3727 BP 826 EP 832 PG 7 WC Engineering, Aerospace; Engineering, Civil; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BM61W UT WOS:000079283700128 ER PT B AU Lessard, DF Rizzuto, DL Bonaldo, D AF Lessard, DF Rizzuto, DL Bonaldo, D BE Alleman, BC Leeson, A TI Optimizing LNAPL recoveries using combined extraction technologies SO IN SITU BIOREMEDIATION OF PETROLEUM HYDROCARBON AND OTHER ORGANIC COMPOUNDS LA English DT Proceedings Paper CT 5th International In Situ and On-Site Bioremediation Symposium CY APR 19-22, 1999 CL SAN DIEGO, CA SP Battelle Mem Inst, Gas Res Inst, IT Grp Inc, Celtic Technol, Parsons Engn Sci Inc, U S Microb Inc, U S Naval Fac Engn Command, Waste Management Inc AB A 3-month pilot study was performed to determine if down-hole hydrocarbon pumps, equipped with hydrophobic filters, can be used as an adjunct to vacuum recovery systems for the efficient recovery of light non-aqueous phase liquid (LNAPL) hydrocarbons. Since onsite groundwater is classified as nonpotable, it not necessary to remediate it beyond the removal of any LNAPL thickness. The study goal was to achieve a higher rate of LNAPL removal without an increase in costs (i.e., additional water treatment), to insure the greatest volume of LNAPL recovery from the subsurface per dollar spent. Application of various stepped vacuums and pumping intervals resulted in an average LNAPL recharge rate increase by an approximate factor of five (5X). Increased product recoveries from 1.5 gallons (gal)/day/well in Phase I of the study to greater than 10 gal/day/well in Phase II were recorded. The dynamic wellfield management techniques tested increased pre-study LNAPL product recovery by 59 percent when compared to similar time intervals for the previous 12-month operational period of high-vacuum dual-phase extraction (HVDPE) operation alone. C1 USAF, Holloman AFB, NM USA. RP Lessard, DF (reprint author), USAF, Holloman AFB, NM USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-076-4 PY 1999 BP 163 EP 168 PG 6 WC Environmental Sciences SC Environmental Sciences & Ecology GA BN62Z UT WOS:000082416200025 ER PT S AU Taferner, WT Mahalingam, K Dorsey, DL Eyink, KG AF Taferner, WT Mahalingam, K Dorsey, DL Eyink, KG BE Auciello, O Krauss, AR Irene, EA Schultz, JA TI Real-time monitoring by spectroscopic ellipsometry and desorption mass spectroscopy during molecular beam epitaxy of AlGaAs/GaAs at high substrate temperatures SO IN SITU PROCESS DIAGNOSTICS AND MODELLING SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium U on In Situ Process Diagnostics and Modelling, at the 1999 MRS Spring Meeting CY APR 06-07, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc ID DEPENDENT OPTICAL-CONSTANTS; GALLIUM; GAAS AB A series of AlGaAs/GaAs depositions were monitored in-situ by spectroscopic ellipsometry and desorption mass spectroscopy, under various substrate temperatures (890 K - 990 K) where non-unity sticking conditions occur. An upper bound on the temperature where AlGaAs/GaAs heterostructures may be grown was determined. Ex-situ cross-sectional transmission electron microscopy verified that the AlGaAs/GaAs layer thicknesses grown by molecular beam epitaxy were accurately determined by spectroscopic ellipsometry at these elevated temperatures. The substrate temperature dependence on Ga desorption rates was consistent with Monte Carlo simulation where desorption from both physisorbed and chemisorbed states were included. C1 MLPO, AFRL, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Taferner, WT (reprint author), MLPO, AFRL, Mat & Mfg Directorate, 3005 P St Ste 6,Bldg 651,Rm 234, Wright Patterson AFB, OH 45433 USA. NR 11 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 1-55899-476-9 J9 MATER RES SOC SYMP P PY 1999 VL 569 BP 107 EP 112 PG 6 WC Chemistry, Applied; Materials Science, Multidisciplinary; Optics SC Chemistry; Materials Science; Optics GA BN69E UT WOS:000082591000014 ER PT S AU Cooley, WT Gurney, ML Dodd, PR Griffy, BW Kelly, J Pressnall, T AF Cooley, WT Gurney, ML Dodd, PR Griffy, BW Kelly, J Pressnall, T BE Andresen, BF Scholl, MS TI Overview of the Air Force Research Laboratory laser applications group active imaging programs SO INFRARED TECHNOLOGY AND APPLICATIONS XXV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXV Conference CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE laser illuminator; search and rescue; active illumination; diode laser application AB The Air Force Research Laboratory (AFRL) laser applications group, also known as "Scorp Works" has been developing user specific, active illumination systems for the past 8 years. A survey of some of these programs will be presented. Programs to be included are the covert adjustable laser illuminator (CALI), the Coast Guard search and rescue laser system (CG-30), a camera automated tracking system(CATS), and a 1.5 mu m covert camera & illuminator. C1 USAF, Res Lab, DELS, Kirtland AFB, NM 87117 USA. RP Cooley, WT (reprint author), USAF, Res Lab, DELS, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 4 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 0-8194-3172-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3698 BP 202 EP 209 DI 10.1117/12.354521 PG 8 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN59F UT WOS:000082322000023 ER PT S AU Gurney, ML Kelly, J AF Gurney, ML Kelly, J BE Andresen, BF Scholl, MS TI The design and field testing of a 1.5 mu m active TV system SO INFRARED TECHNOLOGY AND APPLICATIONS XXV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXV Conference CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE 1.5 mu m; active TV; surveillance; diode laser; laser illumination ID LASER SPOTLIGHT AB The Air Force Research Laboratory (AFRL) laser applications group is developing a 1.5 mu m active TV system for use in military and law enforcement surveillance applications. AFRL supports novel semiconductor laser diode development, recently achieving high power(1) (>1Watt) 1.5 pm devices capable of providing sufficient illumination for an active TV system. This paper presents the components of the 1.5 mu m system and compares its performance to that of a near-IR active TV system operating at 0.81 mu m. A qualitative approach is taken to study the reflective phenomenology of the two systems to determine if operation at 1.5 mu m is viable and advantageous. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Gurney, ML (reprint author), USAF, Res Lab, Directed Energy Directorate, 2550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3172-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3698 BP 244 EP 249 DI 10.1117/12.354525 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN59F UT WOS:000082322000027 ER PT S AU Tzannes, AP Brooks, DH AF Tzannes, AP Brooks, DH BE Andresen, BF Scholl, MS TI Point target detection in IR image sequences based on target and clutter temporal profile modeling SO INFRARED TECHNOLOGY AND APPLICATIONS XXV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXV Conference CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE staring IR camera; point target detection; cloud clutter modeling; target modeling ID FILTERS AB In this paper, we approach the problem of point target detection in infrared image sequences by modeling the temporal behavior of clutter and targets on a single pixel basis. These models, which are experimentally verified, are then used to develop a temporal likelihood ratio test and derive the corresponding decision rule. We demonstrate the effectiveness of the technique by applying it to real infrared image sequences containing targets of opportunity and evolving cloud clutter. The physical models and resulting hypothesis testing approach could also be applicable to other image sequence processing scenarios, using acquisition systems besides infrared imaging, such as detection of small moving objects or structures ina biomedical or biological imaging scenario, or the detection of satellites, meteors or other celestial bodies in night sky imagery acquired using a telescope. C1 USAF, Res Lab, SNHI, Hanscom AFB, MA 01731 USA. RP Tzannes, AP (reprint author), USAF, Res Lab, SNHI, Hanscom AFB, MA 01731 USA. NR 14 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 0-8194-3172-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3698 BP 482 EP 490 DI 10.1117/12.354550 PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN59F UT WOS:000082322000052 ER PT S AU McCarley, P AF McCarley, P BE Andresen, BF Scholl, MS TI Advances in biologically inspired on/near sensor processing SO INFRARED TECHNOLOGY AND APPLICATIONS XXV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXV Conference CY APR 05-09, 1999 CL ORLANDO, FL SP SPIE DE neuromorphic; biomimetic; smart FPA; on-FPA processing AB As electro-optic sensors increase in size and frame rate, the data transfer and digital processing resource requirements also increase. In many missions, the spatial area of interest is but a small fraction of the available field of view. Choosing the right region of interest, however, is a challenge and still requires an enormous amount of downstream digital processing resources. In order to filter this ever-increasing amount of data, we look at how nature solves the problem. The Advanced Guidance Division of the Munitions Directorate, Air Force Research Laboratory (AFRL/MNG) at Eglin AFB, Florida, has been pursuing research in the area of advanced sensor and image processing concepts based on biologically inspired sensory information processing. A summary of two "neuromorphic" processing efforts will be presented along with a seeker system concept utilizing this innovative technology. The Neuroseek program is developing a 256 x 256 2-color dual band IRFPA coupled to an optimized silicon CMOS read-out and processing integrated circuit that provides simultaneous full-frame imaging in MWIR/LWIR wavebands along with built-in biologically inspired sensor image processing functions. Concepts and requirements for future such efforts will also be discussed. C1 USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. RP McCarley, P (reprint author), USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3172-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3698 BP 716 EP 725 DI 10.1117/12.354572 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN59F UT WOS:000082322000076 ER PT B AU Banaszak, D Wolfe, H AF Banaszak, D Wolfe, H GP INST ENVIRONM SCI & TECHNOL INST ENVIRONM SCI & TECHNOL TI Kernel density estimation of peak amplitudes from non-linear random fatigue tests SO INSTITUTE OF ENVIRONMENTAL SCIENCES AND TECHNOLOGY, PROCEEDINGS 1999: CONTAMINATION CONTROL - DESIGN, TEST, AND EVALUATION - PRODUCT RELIABILITY LA English DT Proceedings Paper CT 45th Annual Technical Meeting and Exposition of the IEST on Todays Training for Tomorrows World CY MAY 02-07, 1999 CL ONTARIO, CA SP Inst Environm Sci & Technol DE fatigue; density estimation; time history; peak probability densities; vibration AB In non-linear random fatigue analysis, the probability density function (pdf) of peak values of time histories is used in Miner's rule for random loading. This is often used when fatigue cannot be attributed to sinusoidal stress cycles. There are different methods of counting peaks, which results in different shaped pdfs. Previously (1998), AFRL evaluated three software packages to estimate the pdfs of a 1 second segment of 3 measured time history records (1 for each of three random acceleration input excitation levels: 1.46g, 14.4g and 114g) from recent random fatigue tests on a clamped-clamped-clamped-clamped (C-C-C-C) aluminum panel. These input levels excite 3 of the panel's vibration modes. The analysis was limited to 1 second of data since some of the software packages were limited in number of points. The histograms of peak values gave non-Gaussian looking distributions, which change with excitation level and peak count method. Some of the distributions also have multiple probability modes. The previous evaluation of 1 typical second of data indicated that a kernel density estimate gave a good appearing graphical estimate of the density function. This paper will investigate the changes in the pdfs for the three cases as the number of seconds increase. The length of the 1.46 g record is about 12 seconds or 97491 sample values. The length of the 14.4 g record is about 12 seconds or 97551 sample values. The length of the 114 g record is about 18 seconds or 143,956 sample values. Pdfs using all time history samples, major peak counts and minor peak counts are estimated using Kernel Density Estimation (KDE) toolbox. This paper will also examine the changes in the pdfs obtained from the time histories and using major and minor peak counting methods. Also, the changes in the shape of the density estimates will be examined as the number of seconds analyzed increases to the maximum record length. C1 USAF, Res Lab, Air Vehicles Directorate, AFRL,VASS, Wright Patterson AFB, OH 45433 USA. RP Banaszak, D (reprint author), USAF, Res Lab, Air Vehicles Directorate, AFRL,VASS, Wright Patterson AFB, OH 45433 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU INST ENVIRONMENTAL SCIENCES PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 USA BN 1-877862-66-5 PY 1999 BP 167 EP 174 PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA BN81R UT WOS:000083082600023 ER PT B AU Malas, JC Frazier, WG AF Malas, JC Frazier, WG BE Zabaras, N Becker, R Ghosh, S Lalli, L TI Optimal design of thermomechanical processes using ideal forming concepts SO INTEGRATION OF MATERIAL, PROCESS AND PRODUCT DESIGN LA English DT Proceedings Paper CT Symposium on the Integration of Material, Process and Product Design in Honor of Dr Owen Richmonds 70th Birthday CY OCT 19-20, 1998 CL SEVEN SPRINGS, PA SP Alcoa, Natl Sci Fdn, Ohio State Univ, Cornell Univ ID MATERIAL BEHAVIOR; OPTIMIZATION; DEFORMATION AB New process design and control methods are needed for significantly improving productivity and reducing costs of thermomechanical processes such as hot metal forging. Current practices for accomplishing basic design tasks such as selecting the number of forming steps and specifying the processing conditions for each thermomechanical operation produce feasible solutions that are often far from optimal. Substantial improvements in effectiveness and efficiency can be realized through holistic approaches that optimize the whole system performance and not just individual subsystems such as workpiece material behavior, material flow in dies, and equipment responses. Recent progress in the application of dynamical modeling and process design techniques using ideal forming concepts and trajectory optimization are discussed. Illustrative examples demonstrate potential system optimization benefits of these process design and control strategies. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Malas, JC (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS BN 90-5809-101-5 PY 1999 BP 229 EP 236 PG 8 WC Engineering, Manufacturing; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA BP04N UT WOS:000083968000028 ER PT S AU Agee, FJ AF Agee, FJ BE Brandt, HE TI Research issues and approaches in advanced high power microwave sources SO INTENSE MICROWAVE PULSES VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Intense Microwave Pulses VI CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE High Power Microwave; pulse shortening; ultra-wideband sources; narrowband sources; kylstrons; magnetrons; cathodes; antennas; RF breakdown ID RELTRON TUBES; NARROW-BAND; UNIVERSITY; PROGRESS; HPM AB Presently there is a substantial effort in the US and in laboratories around the world in intense microwave source research. This paper reviews the current state of the art and technical barriers to further progress in producing higher power and higher energy pulses of radiofrequency radiation. The paper also suggests research avenues that offer the potential for further improvements in these sources. Key recent publications and conference proceedings are cited that provide a guide to current thought and recent advances in high power microwave source research. C1 USAF, Off Sci Res, Arlington, VA USA. RP Agee, FJ (reprint author), USAF, Off Sci Res, Arlington, VA USA. NR 34 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 0-8194-3176-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3702 BP 2 EP 7 DI 10.1117/12.351200 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN40L UT WOS:000081825700001 ER PT S AU Umstattd, RJ Shiffler, D Haworth, MD Hendricks, KJ Luginsland, JW Spencer, TA AF Umstattd, RJ Shiffler, D Haworth, MD Hendricks, KJ Luginsland, JW Spencer, TA BE Brandt, HE TI Cesium iodide cathodes for high power microwave devices SO INTENSE MICROWAVE PULSES VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Intense Microwave Pulses VI CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE cesium iodide cathodes; carbon fiber cathodes; high power microwaves; pulse shortening; gap closure; diodes ID PULSE AB A variety of cesium iodide-coated carbon fiber cathodes have been designed and tested for high voltage (300-500 kV), high current (kA) operation. Here, we describe the conditioning process and present the most recent experimental data for a thin annular beam test diode. During these reproducible microsecond-duration pulses, this diode exhibits promising beam impedance maintainability and gap closure speeds of less than 0.4 cm/mu sec. Also presented are recent results for a carbon fiber cathode tested in a relativistic klystron oscillator (RKO) and future plans for such a cathode in a magnetically insulated line oscillator (MILO). C1 USAF, Res Lab, Directed Energy Directorate, Plasma Phys Branch, Kirtland AFB, NM 87117 USA. RP Umstattd, RJ (reprint author), USAF, Res Lab, Directed Energy Directorate, Plasma Phys Branch, Kirtland AFB, NM 87117 USA. NR 6 TC 2 Z9 2 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 0-8194-3176-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3702 BP 8 EP 13 DI 10.1117/12.351207 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN40L UT WOS:000081825700002 ER PT S AU Lehr, JM Kunhardt, EE AF Lehr, JM Kunhardt, EE BE Brandt, HE TI Simulation of electron transport in liquids under high electric fields SO INTENSE MICROWAVE PULSES VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Intense Microwave Pulses VI CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE DE liquid switching; electron transport; high power impulse; ultra-wideband AB High Power Impulse (HPI) generation depends strongly on both the voltage and the rate of voltage rise which is applied to the radiating structure. Thus, placing the peaking switch at the apex of the antenna optimizes the transient radiating system. Liquids are prime candidates for the peaking switch media because of their high dielectric strength and its compatibility with lensing structures. The nature of the electrical breakdown initiation mechanism in liquids is not well understood. Electron processes are confirmed mechanisms of electrical breakdown initiation in gases, and it is natural to seek similar mechanisms for breakdown in the liquid state. The liquid state, however, contains many more scattering centers per unit volume, than in the gaseous state. An electron traveling through a liquid, then, undergoes many more collisions, most of which are inelastic. The electron, then, should quickly lose its energy to the background. Experiments have shown that, contrary to this intuitive conclusion, the electron transport coefficients tend to saturate under very high field conditions. A Monte Carlo simulation technique has been developed to investigate electron transport in liquids under high electric field conditions. This code adapts a computational technique that has been successfully used in electron kinetics of dilute gases by modifying the collisional crossection to accommodate the multiple scattering which occurs in the liquid. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Lehr, JM (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 7 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 0-8194-3176-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3702 BP 47 EP 56 DI 10.1117/12.351217 PG 10 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN40L UT WOS:000081825700007 ER PT B AU Finegold, LS von Gierke, HE Schomer, PD Berry, BF AF Finegold, LS von Gierke, HE Schomer, PD Berry, BF BE Cuschieri, J Glegg, S Yong, Y TI Proposal for monitoring worldwide noise exposure and assessing the effectiveness of noise exposure policies and noise control technologies SO INTER-NOISE 99: PROCEEDINGS OF THE 1999 INTERNATIONAL CONGRESS ON NOISE CONTROL ENGINEERING, VOLS 1-3 LA English DT Proceedings Paper CT International Congress on Noise Control Engineering CY DEC 06-08, 1999 CL FT LAUDERDALE, FL SP Int Inst Noise Control Engn, Inst Noise Control Engn USA C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Finegold, LS (reprint author), USAF, Res Lab, 2255 H St, Wright Patterson AFB, OH 45433 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU INST NOISE CONTROL ENGINEERING PI POUGHKEEPSIE PA PO BOX 3206, ARLINGTON BRANCH, POUGHKEEPSIE, NY 12603 USA BN 0-9622072-3-3 PY 1999 BP 1917 EP 1922 PG 4 WC Acoustics SC Acoustics GA BR05W UT WOS:000165528400357 ER PT B AU Power, GJ AF Power, GJ BE Arabnia, HR TI Structural knowledge for decomposing image sequences SO INTERNATIONAL CONFERENCE ON IMAGING SCIENCE, SYSTEMS, AND TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Imaging Science, Systems, and Technology (CISST 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Korea Informat Processing Soc, Natl Supercomp Ctr Energy & Environm, US DOE, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE image sequence analysis; data storage and retrieval; motion imagery; digital video; video on demand AB The storage and retrieval of digital image sequences is becoming more important with the proliferation of computers, the internet, digital TV and digital cameras. This paper suggests using a prior knowledge in the design to improve the decomposition of digital image sequences for data storage and retrieval. In particular, the paper focuses on the specific image sequence structure which differs depending on the application. Different image sequence structures dictate different image sequence decomposition approaches. Examples of various image sequence structures are given. The structural knowledge of the image sequence is shown to impact the video analysis tools used for decomposition. C1 USAF, Res Lab, Target Recognit Branch, SNAT, Wright Patterson AFB, OH 45433 USA. RP Power, GJ (reprint author), USAF, Res Lab, Target Recognit Branch, SNAT, Bldg 620,2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-19-X PY 1999 BP 325 EP 331 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BN93V UT WOS:000083582800052 ER PT B AU Power, GJ Sturtz, K AF Power, GJ Sturtz, K BE Arabnia, HR TI Objective model for perceptual sharpness in image sequences SO INTERNATIONAL CONFERENCE ON IMAGING SCIENCE, SYSTEMS, AND TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Imaging Science, Systems, and Technology (CISST 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Korea Informat Processing Soc, Natl Supercomp Ctr Energy & Environm, US DOE, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE image sequence analysis; quality; objective assessment; data storage and retrieval; motion imagery; digital video AB Currently, the analog video world is in transition to digital video. Along with that transition is the need for analysis techniques that can be applied to digital image sequences. In particular, objective techniques that can analyze the digital image sequences in a way that reflects human perception is being pursued. These objective measures can be valuable in many areas including quality assessment. Currently, subjective assessment of video is time consuming and expensive. Therefore, an objective assessment that accurately reflects the human visual system can be valuable. This paper examines the perceived quality of shifting and blurred sequences. It introduces an objective quality measure for assessing the sharpness in digital image sequences. The model is compared to two other objective measures and a subjective assessment. C1 USAF, Res Lab, Target Recognit Branch, SNAT, Wright Patterson AFB, OH 45433 USA. RP Power, GJ (reprint author), USAF, Res Lab, Target Recognit Branch, SNAT, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-19-X PY 1999 BP 332 EP 336 PG 3 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BN93V UT WOS:000083582800053 ER PT B AU Arnold, DG Sturtz, K Power, GJ AF Arnold, DG Sturtz, K Power, GJ BE Arabnia, HR TI Analyzing image sequences using invariants SO INTERNATIONAL CONFERENCE ON IMAGING SCIENCE, SYSTEMS, AND TECHNOLOGY, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Imaging Science, Systems, and Technology (CISST 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Korea Informat Processing Soc, Natl Supercomp Ctr Energy & Environm, US DOE, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE invariant 3-D surface construction; modeling ID RECOGNITION AB Recent research in invariant theory has determined the fundamental geometric relation between objects and their corresponding images. This relationship can be used to extract 3-D models from, image sequences. This capability is extremely useful for image sequence compression, understanding, indexing, interpolating, and other applications. This paper presents a high level example of how a 3-D model is constructed from 2-D images. The primary focus is to provide basic understanding of how this result can be exploited to advance research in many applications. C1 USAF, Res Lab, Target Recognit Branch, SNAT, Wright Patterson AFB, OH 45433 USA. RP Arnold, DG (reprint author), USAF, Res Lab, Target Recognit Branch, SNAT, Wright Patterson AFB, OH 45433 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-19-X PY 1999 BP 337 EP 343 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BN93V UT WOS:000083582800054 ER PT B AU Zarecor, R Bennett, M AF Zarecor, R Bennett, M BE Arabnia, HR TI The integration of HPC systems in a test and evaluation real-time environment SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOL VI, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE real time; turbine; HPC; data validation AB In simulated altitude testing of turbine engines, large volumes of data - on the or-tiel of 500, 000 samples/sec -- ale acquired, processed validated, and analyzed. Validation of these data is a labor-intensive effort. Mathematical models have been developed to improve the speed and effectiveness of validation, and the need to run these models in I cal time has been noted, Current AEDC acquisition systems use reflective memory to distribute data among UNIX and NT systems, where they are distributed in a client-server fashion for display and processing. One of these UNIX workstations, The Data Distribution Server, a UNIX workstation, sends the data over a Fast Ethernet link to the High Performance Computer (HPC) system, where the data validation code is run. This link uses of existing fiber-optic cable plant, inexpensive Fast Ethernet interfaces that are now standard on most systems, and commodity networking gear to provide a cost-effective capability to supply a near real-time data stream to the data validation code running on the HPC system. This system reduces the cost of turbine engine testing by reducing the time required to validate data and the number of test points that must be repeated because of bad data. This paper describes ou, approach for transmitting huge quantities of real-time data to a remote HPC system by capitalizing on existing infrastructure. C1 Sverdrup Technol Inc, AEDC Grp, Arnold Engn Dev Ctr, Arnold AFB, TN 37389 USA. RP Zarecor, R (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold Engn Dev Ctr, Arnold AFB, TN 37389 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-14-9 PY 1999 BP 2894 EP 2898 PG 5 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BP04U UT WOS:000083968700035 ER PT B AU Sloan, WR Powell, SM AF Sloan, WR Powell, SM BE Arabnia, HR TI Aeropropulsion test data management system SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOL VI, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE mass storage; data management; archival; retrieval AB An automated data archival and retrieval system has been designed, developed, and implemented to improve the management of aeropropulsion test data at the Arnold Engineering Development Center. (AEDC). Previously, the data archival and retrieval involved a laborious process that included manual tape operations and record keeping. The Test Data Management System (TDMS) utilizes HPC high-volume mass storage systems coupled with specialized and highly automated communications and user interface software for archiving and retrieving. Acquired, performance, and mathematical model data for the Engine Test Facility (ETF) at AEDC are now automatically archived. In addition, custom software, instrumentation information, and various support files used in the data production process ale archived with the data. he archived data may be retrieved automatically front the mass storage system for further processing or analysis as desired. The Test Data Management System can be accessed directly via a graphical user interface that provides visibility to information stored on the archival system and the capability for. the user to retrieve these data. An application programming interface (API) library has also been developed for programmatic access by various applications. The system was designed to provide maximum flexibility and expandability for various data types and data formats. Enhancements have been proposed to support the definition, storage, and user queries on an expanded set of metadata. This paper describes the AEDC Aeropropulsion Test Data Management System in greater detail, the underlying software and Management highlighting rn hardware design. C1 Sverdrup Technol Inc, AEDC Grp, Arnold Engn Dev Ctr, Arnold AFB, TN 37389 USA. RP Sloan, WR (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold Engn Dev Ctr, Arnold AFB, TN 37389 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-14-9 PY 1999 BP 2899 EP 2905 PG 7 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering; Computer Science, Theory & Methods SC Computer Science GA BP04U UT WOS:000083968700036 ER PT B AU Bohn, CA Lamont, GB AF Bohn, CA Lamont, GB BE Arabnia, HR TI Asymmetric load balancing on a heterogeneous cluster of PCs SO INTERNATIONAL CONFERENCE ON PARALLEL AND DISTRIBUTED PROCESSING TECHNIQUES AND APPLICATIONS, VOLS I-V, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Parallel and Distributed Processing Techniques and Applications (PDPTA 99) CY JUN 28-JUL 01, 1999 CL LAS VEGAS, NV SP Comp Sci Res Educ & Applicat Press, Comp Vis Res & Applicat Tech, Int Assoc Math & Comp Simulat, Int Technol Inst, Java High Performance Comp Res Grp, Korea Informat Processing Soc, US DOE, Natl Supercomp Ctr Energy & Environm Las Vegas, Sundance Digital Signal Processing Inc, World Sci & Engn Soc DE pile of PCs; load balancing; Linux AB With commercial supercomputers and homogeneous clusters of PCs, static load balancing is accomplished by assigning equal tasks to each processor. With heterogeneous clusters, system designers have the option of adding newer hardware that is more powerful than existing hardware. When this is done, assignment of equal tasks to each processor yields suboptimal performance. This research addresses techniques by which the sizes of the tasks are suitably matched to the processors and memories. Thus, more powerful nodes do more work, and less powerful nodes perform less work. We find Mat when, the range of processing power is narrow, some benefit can be achieved with asymmetric load balancing. When the range of processing pourer is broad, dramatic improvements in. performance are realized - our experiments have shown up to 92% improvement when asymmetrically load balancing a modified version of the NAS Parallel Benchmarks' LU application on a heterogeneous cluster of Linux-powered PCs. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Bohn, CA (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU C S R E A PRESS PI ATHENS PA 115 AVALON DR, ATHENS, GA 30606 USA BN 1-892512-15-7 PY 1999 BP 2515 EP 2522 PG 8 WC Computer Science, Hardware & Architecture; Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Mathematics, Applied SC Computer Science; Engineering; Mathematics GA BR81L UT WOS:000167653300376 ER PT J AU Liggett, KK Reising, JM Hartsock, DC AF Liggett, KK Reising, JM Hartsock, DC TI Development and evaluation of a background attitude indicator SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article ID PRECEDENCE AB In this article, we describe a series of 3 studies conducted to evaluate the feasibility of using a unique type of attitude indicator, called a background attitude indicator (BAI), to recover from unusual attitudes. The BAI is a head-down display format that combines tactical information in the central portion of the display with attitude information in the border surrounding the tactical information. The attitude information, in essence, frames the tactics display. The results of the 3 studies showed that BAIs in general are capable of portraying enough attitude information to enable pilots to recover from unusual attitudes. Specifically, BAIs being used for unusual attitude recovery tasks should contain continuous flow patterns that allow pilots to determine approximate attitude (pitch) quickly. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Veridian, Veda Operat, Dayton, OH USA. RP Reising, JM (reprint author), USAF, Res Lab, WL FIPA Bldg 146,2210 8th St,Suite 1, Wright Patterson AFB, OH 45433 USA. NR 15 TC 3 Z9 3 U1 2 U2 2 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 1999 VL 9 IS 1 BP 49 EP 71 DI 10.1207/s15327108ijap0901_4 PG 23 WC Psychology, Applied SC Psychology GA 155ZV UT WOS:000077977700004 ER PT J AU Previc, FH Ercoline, WR AF Previc, FH Ercoline, WR TI The "outside-in" attitude display concept revisited SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article ID STATES-AIR-FORCE; SPATIAL DISORIENTATION; VECTION; ORIENTATION; PERFORMANCE; SYMBOLOGY; MOTION; DEPTH; TASK AB The "outside-in" attitude display concept, which includes a moving-aircraft (as opposed to a moving-horizon) attitude reference, dates back to the early days of flying. The majority of the laboratory and in-flight studies that have evaluated the outside-in format over the years have found it to be superior at preventing roll-reversal errors during normal flying and in recovering from unusual attitudes. Although outside-in attitude displays have been, and continue to be, flown throughout the world, the majority of military and civilian aircraft have failed to adopt this format. This article reviews the purported advantages and disadvantages of outside-in displays, presents a neuropsychological explanation for their general superiority in maintaining spatial orientation, and describes 3 new situations (off-axis helmet-mounted display viewing, global situation displays, and control of uninhabited aerial vehicles) for which the outside-in concept appears to be ideally suited. C1 USAF, Res Lab, Brooks AFB, TX USA. Veridian Inc, Brooks AFB, TX USA. RP Previc, FH (reprint author), TASC Inc, 4241 Woodstock Dr,Suite B100, San Antonio, TX 78228 USA. NR 70 TC 23 Z9 24 U1 1 U2 3 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 1999 VL 9 IS 4 BP 377 EP 401 DI 10.1207/s15327108ijap0904_5 PG 25 WC Psychology, Applied SC Psychology GA 262ZJ UT WOS:000084097900005 ER PT J AU Gordnier, RE Visbal, MR AF Gordnier, RE Visbal, MR TI Numerical simulation of the impingement of a streamwise vortex on a plate SO INTERNATIONAL JOURNAL OF COMPUTATIONAL FLUID DYNAMICS LA English DT Article DE streamwise vortex impingement; vortex breakdown; tail buffet ID BOUNDARY-LAYER INTERACTIONS; BREAKDOWN ONSET; FLOW STRUCTURE; COMPUTATION; FLOWFIELD; SURFACE AB The flow field generated by the impingement of a delta-wing vortex on a plate is examined computationally. The flow is simulated by solving the unsteady, three-dimensional Navier-Stokes equations on an overset grid system using a time accurate, implicit Beam and Warming algorithm. Comparison of the computed solutions for two levels of mesh resolution indicates that no additional flow features appear with grid refinement. Both the mean and unsteady flow structures are examined. Over the delta wing the flow exhibits a spiral vortex breakdown induced by the plate. Underneath the plate a highly unsteady, large-scale (owl-type) stall region is formed and results in the shedding of hairpin-like vortical structures. On the top surface of the plate a shallow separation region also exists outboard of the vortex impingement location. These separated flow features result from the spanwise variation in effective angle of attack created by the incoming vortex system. Also present over the upper surface is a mean longitudinal vortical structure arising from the passage of segments of the spiral filament. The frequency of the surface pressure fluctuations at a point on the plate leading edge that corresponds to the spiral mode of breakdown is found to be in agreement with experimental measurements. The mutual interaction between the breakdown and the stalled how is explored. A pronounced sensitivity of breakdown location to the degree of obstruction created by the plate separation is found. This feedback effect might suggest possible flow control strategies. C1 USAF, Res Lab, VAAC, Computat Sci Branch,Aeronaut Sci Div, Wright Patterson AFB, OH 45433 USA. RP Gordnier, RE (reprint author), USAF, Res Lab, VAAC, Computat Sci Branch,Aeronaut Sci Div, Bldg 450,2645 5th St,Ste 7, Wright Patterson AFB, OH 45433 USA. NR 39 TC 7 Z9 7 U1 0 U2 4 PU GORDON BREACH SCI PUBL LTD PI READING PA C/O STBS LTD, PO BOX 90, READING RG1 8JL, BERKS, ENGLAND SN 1061-8562 J9 INT J COMPUT FLUID D JI Int. J. Comput. Fluid Dyn. PY 1999 VL 12 IS 1 BP 49 EP + DI 10.1080/10618569908940815 PG 24 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 237AE UT WOS:000082630800004 ER PT J AU Maudlin, PJ Bingert, JF House, JW Chen, SR AF Maudlin, PJ Bingert, JF House, JW Chen, SR TI On the modeling of the Taylor cylinder impact test for orthotropic textured materials: experiments and simulations SO INTERNATIONAL JOURNAL OF PLASTICITY LA English DT Article ID MULTISURFACE PLASTICITY; YIELD SURFACE; TANTALUM; DEFORMATION; BEHAVIOR AB Taylor impact tests using specimens cut from a rolled plate of tantalum were conducted. The tantalum was experimentally characterized in terms of flow stress and crystallographic texture. A piece-wise yield surface was interrogated from an ODF corresponding to this texture assuming two slip system modes, in conjunction with an elastic stiffness tensor computed from the same ODF and single crystal elastic properties. This constitutive information was used in EPIC-95 3D simulations of a Taylor impact test, and good agreement was realized between the calculational results and the experimental post-test geometries in terms of major and minor side profiles and impact-interface footprints. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. RP Maudlin, PJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 29 TC 56 Z9 56 U1 0 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0749-6419 J9 INT J PLASTICITY JI Int. J. Plast. PY 1999 VL 15 IS 2 BP 139 EP 166 DI 10.1016/S0749-6419(98)00058-8 PG 28 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 184EM UT WOS:000079597500002 ER PT J AU Buryachenko, V AF Buryachenko, V TI Elastic-plastic behavior of elastically homogeneous materials with a random field of inclusions SO INTERNATIONAL JOURNAL OF PLASTICITY LA English DT Article DE thermomechanical processes; elastic-plastic material; homogeneous material ID METAL-MATRIX COMPOSITES; EFFECTIVE ELASTOPLASTIC BEHAVIOR; MORI-TANAKA THEORY; RESIDUAL-STRESSES; PARTICULATE COMPOSITES; MICROMECHANICAL INVESTIGATIONS; REINFORCED COMPOSITES; 2-PHASE COMPOSITES; LOCAL THEORY; FLUCTUATIONS AB A multiphase material is considered, which consists of a homogeneous elastic-plastic matrix containing a homogeneous statistically uniform random set of ellipsoidal elastic-plastic inclusions. The elastic properties of the matrix and the inclusions are the same, but the so-called "stress-free strains", i.e. the strain contributions due to temperature loading, phase transformations, and the plastic strains, fluctuate. A general theory of the yielding for arbitrary loading (by the stress and by the temperature) is employed. The realization of an incremental plasticity scheme is based on averaging over each component of the nonlinear yield criterion. Usually, averaged stresses are used inside each component for this purpose. In distinction from this usual practice physically consistent assumptions about the dependence of these functions on the component's values of the second stress moments are applied. The application of the proposed theory to the prediction of the thermomechanical deformation behavior of a model material is shown. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Mat Directorate, AFRL MLBC, Wright Patterson AFB, OH 45433 USA. RP Buryachenko, V (reprint author), USAF, Res Lab, Mat Directorate, AFRL MLBC, Wright Patterson AFB, OH 45433 USA. EM buryach@aol.com NR 75 TC 12 Z9 12 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0749-6419 J9 INT J PLASTICITY JI Int. J. Plast. PY 1999 VL 15 IS 7 BP 687 EP 720 DI 10.1016/S0749-6419(99)00008-X PG 34 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics SC Engineering; Materials Science; Mechanics GA 220WK UT WOS:000081691000001 ER PT J AU Evans, DB O'Brien, WJ AF Evans, DB O'Brien, WJ TI Fracture strength of glass infiltrated-magnesia core porcelain SO INTERNATIONAL JOURNAL OF PROSTHODONTICS LA English DT Article ID CERAMIC RESTORATIONS; ALUMINA; CROWNS AB Purpose: This study determined the fracture strength of magnesia-core porcelain after using a glass infiltration firing technique. Materials and Methods: Eighty refractory dies were replicated from a stainless steel master die milled to the dimensions of a maxillary premolar that had been prepared for a porcelain crown. The core porcelain was applied to the refractory dies using traditional condensation methods, and then formed into standardized copings using a centrifugal sculpturing device. The copings were vacuum-fired from 593 degrees C to 1 of 8 high temperatures. Five copings per temperature were then coated with a glass-infiltrate and ground back to a standard thickness. The finished copings were bonded to a duplicate die with an adhesive resin luting system and placed in an Instron testing machine and loaded to fracture. Results: Analysis of variance and Student-Newman-Keuls tests demonstrated significant differences among treatments and temperatures (P < 0.05). A significant increase in fracture strength was observed after glass infiltration of the magnesia-core porcelain. Sintering the copings to 871 degrees C or 899 degrees C prior to glass infiltration gave the highest fracture load values. Conclusion: Class infiltration significantly increased the fracture strength of the magnesia-core porcelain. C1 USAF, Dent Corps, Area Dent Lab, Kadena Air Base, Okinawa, Japan. Univ Michigan, Sch Dent, Specialized Mat Res Ctr, Ann Arbor, MI USA. RP Evans, DB (reprint author), SGDA, Dent Squadron 18, Kadena Area Dent Lab, Unit 5270, APO, AP 96368 USA. NR 27 TC 2 Z9 3 U1 0 U2 0 PU QUINTESSENCE PUBL CO INC PI CAROL STREAM PA 551 NORTH KIMBERLY DR, CAROL STREAM, IL 60188-1881 USA SN 0893-2174 J9 INT J PROSTHODONT JI Int. J. Prosthodont. PD JAN-FEB PY 1999 VL 12 IS 1 BP 38 EP 44 PG 7 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 160UA UT WOS:000078248400005 PM 10196826 ER PT J AU Fournier, LR Wilson, GF Swain, CR AF Fournier, LR Wilson, GF Swain, CR TI Electrophysiological, behavioral, and subjective indexes of workload when performing multiple tasks: manipulations of task difficulty and training SO INTERNATIONAL JOURNAL OF PSYCHOPHYSIOLOGY LA English DT Article DE EEG; ERD; ERS; EGG; alpha; work load; theta; training ID EVENT-RELATED DESYNCHRONIZATION; ALPHA-DESYNCHRONIZATION; SEMANTIC MEMORY; EEG; ERD; SYNCHRONIZATION; DISSOCIATION; RESPIRATION; MOVEMENT AB This study examined whether alpha event-related desynchronization (ERD) and theta event-related synchronization (ERS) could successfully measure changes in cognitive workload and training while an operator was engaged in a continuous, interactive, control task(s). Alpha 1 (8-10 Hz) ERD, alpha 2 (10-12 Hz) ERD, and theta (3-7 Hz) ERS were determined for a communications event that occurred during multiple task workload conditions or as a single task. Other measures (alpha and theta EEG power, heart rate, respiration, eye blinks, behavioral performance, and subjective workload ratings) were also evaluated. Results showed that alpha 2 EEG, heart rate, behavioral, and subjective measures were sensitive to changes in workload in the multiple tasks. In addition, eye blink rate and behavioral measures were sensitive to training. Alpha ERD and theta ERS were not sensitive to workload and training in our interactive, multiple task environment. However, they we re effective indexes of cognitive/behavioral demands within an interactive single task. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Washington State Univ, Dept Psychol, Pullman, WA 99164 USA. USAF, Res Lab, Dayton, OH USA. Logicon Tech Serv Inc, Dayton, OH USA. RP Fournier, LR (reprint author), Washington State Univ, Dept Psychol, Pullman, WA 99164 USA. EM fournier@wsunix.wsu.edu NR 46 TC 51 Z9 54 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8760 J9 INT J PSYCHOPHYSIOL JI Int. J. Psychophysiol. PD JAN PY 1999 VL 31 IS 2 BP 129 EP 145 DI 10.1016/S0167-8760(98)00049-X PG 17 WC Psychology, Biological; Neurosciences; Physiology; Psychology; Psychology, Experimental SC Psychology; Neurosciences & Neurology; Physiology GA 162XF UT WOS:000078371900004 PM 9987059 ER PT J AU Roberts, RG Repperger, DW AF Roberts, RG Repperger, DW TI On closed form expressions for the singular-value decomposition of an orientational Jacobian and its application to a motion simulator SO INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH LA English DT Article ID KINEMATICALLY REDUNDANT MANIPULATORS; ROBOT; MANIPULABILITY; OPERATION AB This article presents some results on the closed-form, singular-value decomposition of the orientational Jacobian for three- and four-degree-of-freedom wristlike mechanisms. These results are used to study the kinematics of a centrifuge simulator and to determine the centrifuge's limitations in achieving maximum angular velocities. Also the issue of fault tolerance for a redundant wrist is addressed. C1 Florida State Univ, Coll Engn, FAMU, Dept Elect Engn, Tallahassee, FL 32310 USA. USAF, Res Lab, HECP, AFRL, Wright Patterson AFB, OH 45433 USA. RP Florida State Univ, Coll Engn, FAMU, Dept Elect Engn, 2525 Pottsdamer St, Tallahassee, FL 32310 USA. EM ee@eng.fsu.edu NR 14 TC 0 Z9 0 U1 0 U2 0 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0278-3649 EI 1741-3176 J9 INT J ROBOT RES JI Int. J. Robot. Res. PD JAN PY 1999 VL 18 IS 1 BP 109 EP 115 PG 7 WC Robotics SC Robotics GA 160AU UT WOS:000078208800007 ER PT S AU Fuller-Rowell, TJ Matsuo, T Codrescu, MV Marcos, FA AF Fuller-Rowell, TJ Matsuo, T Codrescu, MV Marcos, FA BE Burns, A Killeen, T Rees, D TI Modeling thermospheric neutral density waves and holes in response to high latitude forcing SO IONOSPHERIC/THERMOSPHERIC/MESOSPHERIC COUPLING SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT C1 1 and C1 2 Symposia of COSPAR Scientific Commission C Held at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP Comm Space Res, Int Union Geodesy & Geophys Int Assoc Geomagnetism & Aeron, Int Union Radio Sci, Sci Comm Solar Terr Phys, Int Union Geodesy & Geophys Int Assoc Meteorol & Atmospher Sci ID ELECTRIC-FIELDS; IONOSPHERIC ELECTRODYNAMICS; CURRENTS AB Numerical simulations have been performed to model the neutral density response to two substorms in March 1979. Observations of density from the Satellite Electrostatic Triaxial Accelerometer (SETA) during this interval revealed neutral density waves propagating from high latitudes in response to the substorms. For the first substorm, waves were seen on both the day and nightside in the Northern Hemisphere, and for the second, only strong nightside waves were detected. The data also revealed the formation of deep neutral density "holes" at high latitudes. To simulate the response, a coupled thermosphere ionosphere model was driven by an empirical substorm model designed to follow the various phases of the substorms. By tuning the magnitude of the energy injection and, in one case, rotating the spatial distribution of the sources, bath the wave features on the day and nightside, and the neutral density holes were reproduced. The neutral density waves were found to be consistent with the passage of atmospheric gravity waves with propagation speeds of 600 to 700 m/s. The neutral density holes are dynamically driven, created by the high velocity neutral winds from ion-drag. During strong geomagnetic activity momentum forcing resulting from ion-drag drives neutral winds of several hundreds of m/s. Inertial forces on the gas parcels cause a divergence in the vortex-like circulation. Backpressure induced by the divergent wind field does not completely balance the flow, and air rises within the vortex core, to maintain continuity, and cools adiabatically to produce a low temperature. Due to the cooling that takes place, in spite of the strong Joule heating that must accompany the ion-drag, the cold vortex core appears as a density hole. The physical model is able to reproduce the magnitude and location of the density holes. The study indicates that physical models, with well-defined magnetospheric inputs, will be able to improve neutral density specification for orbital tracking during period of high geomagnetic activity. (C) 1999 COSPAR. Published by Elsevier Science Ltd. C1 Univ Colorado, CIRES, Boulder, CO 80303 USA. NOAA, Space Environm Lab, Boulder, CO 80303 USA. SUNY Stony Brook, MSCR, Stony Brook, NY 11794 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Univ Colorado, CIRES, 325 Broadway, Boulder, CO 80303 USA. NR 21 TC 10 Z9 10 U1 0 U2 3 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES-SERIES PY 1999 VL 24 IS 11 BP 1447 EP 1458 DI 10.1016/S0273-1177(99)00705-X PG 12 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA BP27H UT WOS:000084544200004 ER PT S AU McMackin, L Zetocha, P Sparkman, C McIntire, H Fetrow, M Bishop, K AF McMackin, L Zetocha, P Sparkman, C McIntire, H Fetrow, M Bishop, K BE Perry, M TI Intelligent optical polarimetry development for space surveillance missions SO ISAIRAS '99: FIFTH INTERNATIONAL SYMPOSIUM ON ARTIFICIAL INTELLIGENCE, ROBOTICS AND AUTOMATION IN SPACE SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT 5th International Symposium on Artificial Intelligence, Robotics and Automation in Space (ISAIRAS 99) CY JUN 01-03, 1999 CL NOORDWIJK, NETHERLANDS SP European Space Agcy, Italian Space Agcy, Italy, French Natl Space Agcy, France, Inst Space & Astronaut Sci, Japan, Natl Aerosp Lab, Japan, NASA, US, Natl Space Dev Agcy, Japan, Netherlands Agcy Aerosp Programs, Netherlands AB The rapidly increasing numbers and complexity of earth-orbiting satellites in recent decades has placed heavy demands upon telemetry and ground support equipment and personnel to maintain and control the systems. A major thrust of current space program developments is the reduction of dependence upon ground control for normal satellite operations. This paper describes one such experiment currently under development at the Air Force Research Laboratory (AFRL) which addresses these needs. The experiment combines an optical polarimeter for measurement of multi-spectral polarization signals of orbiting objects and a system of intelligent software agents which will provide automated payload and bus control. We discuss the development of the optical system hardware, software agent development, and aspects of the processing and control of information from on-board data. C1 USAF, Res Lab, Space Sensing & Vehicle Control Branch, AFRL,VSSS, Kirtland AFB, NM 87117 USA. RP McMackin, L (reprint author), USAF, Res Lab, Space Sensing & Vehicle Control Branch, AFRL,VSSS, Kirtland AFB, NM 87117 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-760-7 J9 ESA SP PUBL PY 1999 VL 440 BP 199 EP 203 PG 5 WC Automation & Control Systems; Engineering, Aerospace; Computer Science, Artificial Intelligence; Computer Science, Interdisciplinary Applications SC Automation & Control Systems; Engineering; Computer Science GA BN59B UT WOS:000082313700027 ER PT B AU Tumbush, G Bhatia, D AF Tumbush, G Bhatia, D GP IEEE IEEE TI Clustering to improve bi-partition quality and run time SO ISCAS '99: PROCEEDINGS OF THE 1999 IEEE INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOL 6: CIRCUITS ANALYSIS, DESIGN METHODS, AND APPLICATIONS LA English DT Proceedings Paper CT 1999 IEEE International Symposium on Circuits and Systems (ISCAS 99) CY MAY 30-JUN 02, 1999 CL ORLANDO, FL SP IEEE AB Circuit partitioning is a very extensively studied problem. Traditional heuristic methods used to solve these problems degrade in performance when the problem size becomes large. Clustering has been proposed as a method to reduce the problem size, allowing the problem to be solved faster and with more accuracy. In [7] we propose a novel bi-partitioning method based on a mathematical formulation of the problem which can be solved using commercial combinatorial optimization (CO) tools. In this paper we continue to formulate the problem as a nonlinear program (NLP) but also apply clustering to determine if run-time and quality can be improved. C1 USAF, Res Labs, IFTA, Wright Patterson AFB, OH 45433 USA. RP Tumbush, G (reprint author), USAF, Res Labs, IFTA, 2241 Avion Circle STE 32, Wright Patterson AFB, OH 45433 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 0-7803-5472-9 PY 1999 BP 145 EP 148 PG 4 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BN36P UT WOS:000081715900037 ER PT S AU Bussjager, R Osman, J Chaiken, J Getbehead, M Hinkel, D McEwen, T AF Bussjager, R Osman, J Chaiken, J Getbehead, M Hinkel, D McEwen, T GP SOC PHOTOOPT INSTRUMENTAT ENGINEERS SOC PHOTOOPT INSTRUMENTAT ENGINEERS TI Examination of tungsten oxide based thin films for optical memory SO JOINT INTERNATIONAL SYMPOSIUM ON OPTICAL MEMORY AND OPTICAL DATA STORAGE 1999 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Joint International Symposium on Optical Memory and Optical Data Storage (ISOM/ODS 99) CY JUL 11-15, 1999 CL KOLOA, HI SP IEEE, Lasers & Electroopt Soc, Opt Soc Amer, SPIE, Int Soc Opt Engn, Japan Soc Appl Phys C1 USAF, Res Lab, SNDP, Griffiss AFB, NY 13441 USA. RP Bussjager, R (reprint author), USAF, Res Lab, SNDP, 25 Electron Pkwy, Griffiss AFB, NY 13441 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3458-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3864 BP 249 EP 251 PG 3 WC Computer Science, Hardware & Architecture; Optics; Physics, Applied SC Computer Science; Optics; Physics GA BN96P UT WOS:000083679500079 ER PT J AU McGrath, CM Bellville, ES Whisman, BA AF McGrath, CM Bellville, ES Whisman, BA TI The effect of asthma education on outcomes of asthma. SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JAN PY 1999 VL 103 IS 1 SU S MA 290 BP S76 EP S76 PN 2 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA 165FC UT WOS:000078509000297 ER PT J AU Tankersley, MS Walker, RL Hagan, LL Butler, WK Jacobs, JS Smart, SJ McGrath, CM Freeman, TM AF Tankersley, MS Walker, RL Hagan, LL Butler, WK Jacobs, JS Smart, SJ McGrath, CM Freeman, TM TI Safety and efficacy of an imported fire ant rush immunotherapy protocol with and without prophylactic treatment. SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JAN PY 1999 VL 103 IS 1 SU S MA 692 BP S181 EP S181 PN 2 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA 165FC UT WOS:000078509000695 ER PT J AU Walker, R Jacobs, J Tankersley, M Hagan, L Freeman, T AF Walker, R Jacobs, J Tankersley, M Hagan, L Freeman, T TI Rush immunotherapy (RIT) for the prevention of debilitating large local reactions (LLR) secondary to imported fire ant (IFA) stings. SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 7 Z9 7 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0091-6749 J9 J ALLERGY CLIN IMMUN JI J. Allergy Clin. Immunol. PD JAN PY 1999 VL 103 IS 1 SU S MA 691 BP S180 EP S181 PN 2 PG 2 WC Allergy; Immunology SC Allergy; Immunology GA 165FC UT WOS:000078509000694 ER PT J AU Roberson, SL Finello, D Davis, RF AF Roberson, SL Finello, D Davis, RF TI Electrochemical evaluation of molybdenum nitride electrodes in H2SO4 electrolyte SO JOURNAL OF APPLIED ELECTROCHEMISTRY LA English DT Article DE molybdenum nitride electrodes; capacitors; H2SO4 electrolytes ID SURFACE-AREA; THIN-FILMS AB The electrochemical stability of polycrystalline thin film MoxN (x = 1 and 2) electrodes deposited on previously nitrided polycrystalline Ti and bare Ti substrates and exposed to 4.4 M H2SO4 electrolyte has been investigated. The electrodes were prepared by a temperature programmed procedure involving the reaction of MoO3 films and NH3. Cyclic voltammetry and a.c. impedance spectroscopy indicated that the range of electrochemical voltage stability in the electrolyte of the MoxN films on nitrided Ti substrates, referenced to a standard hydrogen electrode to be -0.01 to + 0.69 V. These electrodes had a calculated capacitance of about 315 F cm(-3). The MoxN films on Ti substrates were electrochemically stable from -0.01 to + 0.67 V; however, they contained unconverted MoO2 which acted to reduce the calculated capacitance to about 210 F cm(-3). At and above + 0.70 V and + 0.68 V on nitrided Ti and Ti substrates, respectively, an electrochemical reaction occurred. The formation of an amorphous phase in the reacted MoxN films was indicated by X-ray diffraction (XRD). Secondary ion mass spectroscopy (SIMS) showed increases in the atomic concentrations of hydrogen, oxygen and sulfur in the reacted films. The voltage bias applied to the electrodes influenced the chemical composition of the reacted films. C1 N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA. RP Roberson, SL (reprint author), USAF, Res Labs, Munit Directorate, Bldg 432 Fuzes Branch,306 W Eglin Blvd, Eglin AFB, FL 32542 USA. RI Davis, Robert/A-9376-2011 OI Davis, Robert/0000-0002-4437-0885 NR 10 TC 14 Z9 14 U1 2 U2 20 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0021-891X J9 J APPL ELECTROCHEM JI J. Appl. Electrochem. PD JAN PY 1999 VL 29 IS 1 BP 75 EP 80 DI 10.1023/A:1003460529736 PG 6 WC Electrochemistry SC Electrochemistry GA 173GA UT WOS:000078971700011 ER PT J AU Bai, SJ Srinivasan, KR Tan, LS Spry, RJ Price, GE AF Bai, SJ Srinivasan, KR Tan, LS Spry, RJ Price, GE TI Enhanced electrical properties of rigid-rod polymer incorporated with electroactive triarylamino moieties SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID X-RAY-SCATTERING; NONLINEAR-OPTICAL-PROPERTIES; APROTIC ORGANIC-SOLVENTS; PARA-AROMATIC POLYMERS; MOLECULAR COMPOSITES; LADDER POLYMERS; MAIN-CHAIN; CONDUCTING POLYTRIPHENYLAMINES; PHENYLENE BENZOBISTHIAZOLE; THERMAL-PROPERTIES AB Oxidatively stable and electrically insulating rigid-rod polymer poly(p-phenylenebenzobisthiazole) (PBT), was incorporated with electroactive triarylamino (TPA) moieties, (R)TPA-PBT with R = NMe2 and Me. Copolymers or homopolymers were synthesized with various TPA fractions changing the polymers to segmentally rigid configuration, and fabricated into films. On cast films, x-ray scattering revealed that the copolymers were random copolymers, microscopy showed "template effect'' from the rigid segments. Iodine activation of the incorporated polymers led consistently to more than five order-of-magnitude increases in electrical conductivity. The activated conductivity also increased with TPA fraction. A conductivity value as high as 4.1 x 10(-4) S/cm was realized for the activated (NMe2)TPA-PBT homopolymer. However, temporal stabilities were observed for the conductivity, which seemed to depend on the polymer composition and film morphology. Spectroscopic examination detected no new electronic state generated by iodine doping. Instead, optical absorbance was drastically increased for h nu greater than 2 eV with a change in film color. Both enhanced conductivity and absorbance were not exhibited by the iodine-activated PBT polymer. (C) 1999 American Institute of Physics. [S0021-8979(99)04001-3]. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. SYSTRAN Corp, Dayton, OH 45432 USA. USAF, Res Lab, ML MLBP, Wright Patterson AFB, OH 45433 USA. RP Bai, SJ (reprint author), Natl Sun Yat Sen Univ, Inst Mat Sci & Engn, Kaohsiung 80424, Taiwan. RI Tan, Loon-Seng/F-6985-2012 OI Tan, Loon-Seng/0000-0002-2134-9290 NR 47 TC 6 Z9 6 U1 0 U2 0 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 1999 VL 85 IS 1 BP 280 EP 286 DI 10.1063/1.369442 PG 7 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200041 ER PT J AU Manasreh, MO von Bardeleben, HJ Mousalitin, AM Khokhlov, DR AF Manasreh, MO von Bardeleben, HJ Mousalitin, AM Khokhlov, DR TI Electron irradiation effects on the intersubband transitions in InGaAs/AlGaAs multiple quantum wells SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INFRARED-ABSORPTION; INDUCED DEFECTS; GAAS AB Intersubband transitions in InGaAs/AlGaAs multiple quantum wells were studied under the influence of electron irradiation using the optical absorption technique. The intensity of the intersubband transition was dramatically decreased in samples irradiated with 2 MeV electron beams and doses higher than 1 X 10(17) cm(-2). This reduction was interpreted as being due to the trapping of the two-dimensional electrons gas in the quantum wells by the irradiation-induced defects. The total integrated area of the intersubband transition in irradiated samples was studied as a function of temperature. The results show that two irradiation-induced traps are involved in capturing and then releasing the confined electrons as the temperature is lowered to 77 K and then increased to 300 K. (C) 1999 American Institute of Physics. [S0021-8979(99)06501-9]. C1 USAF, Res Lab AFRL VSSS, Kirtland AFB, NM 87117 USA. Univ Paris 06, Phys Solides Grp, F-75251 Paris 05, France. Univ Paris 07, Phys Solides Grp, F-75251 Paris 05, France. Moscow Steel & Alloys Inst, Moscow 117936, Russia. Moscow MV Lomonosov State Univ, Dept Phys, Moscow 119899, Russia. RP Manasreh, MO (reprint author), USAF, Res Lab AFRL VSSS, 3550 Aberdeen Ave SE,Bldg 426, Kirtland AFB, NM 87117 USA. RI Khokhlov, Dmitry/F-3370-2010 NR 17 TC 10 Z9 10 U1 1 U2 2 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 1999 VL 85 IS 1 BP 630 EP 632 DI 10.1063/1.369419 PG 3 WC Physics, Applied SC Physics GA 148DM UT WOS:000077489200102 ER PT J AU Byczkowski, JZ Channel, SR Miller, CR AF Byczkowski, JZ Channel, SR Miller, CR TI A biologically based pharmacodynamic model for lipid peroxidation stimulated by trichloroethylene in vitro SO JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY LA English DT Article DE trichloroethylene; lipid peroxidation; liver slices; mathematical model; free radicals ID MATHEMATICAL-MODEL; OXIDATIVE STRESS; PROLIFERATION; KERATINOCYTES; ANTIOXIDANTS; SIMULATION; SLICES; LIVER; ACID AB It is often necessary for chemical risk assessment to determine a quantitative relationship between the internal dose of a chemical and its biological effect. The tool best suited for this purpose is a biologically based pharmacodynamic (BBPD) model. Such a BBPD model was developed previously (10) to simulate chemically induced lipid peroxidation, and it was experimentally calibrated in precision-cut mouse liver slices in vitro. The BBPD model simulated formation of lipid hydroperoxides and thiobarbituric acid reactive substances (TEARS) over time and was originally calibrated with different concentrations of tert-butyl hydroperoxide and bromotrichloromethane. The objective of the present work is to refine this BBPD model so it can describe the kinetics and the dose response of lipid peroxidation induced by a weakly prooxidant chemical, trichloroethylene (TCE). The chemical-dependent model parameters were optimized to reflect the chemistry of TCE. Two basic algorithms, linear and square root, for the description of stoichiometric free radical production from TCE were tested. Predictions with the square root algorithm fit the experimental data employing TEARS as an end point better than those by the linear algorithm. The calibrated BBPD model will be used to support our future mathematical description of TCE pharmacodynamics in vivo. (C) 1999 John Wiley & Sons, Inc. C1 Mantech Environm Technol Inc, Dayton, OH 45437 USA. TN & Associates Inc, Cincinnati, OH 45256 USA. USAF, Res Lab, Operat Toxicol Branch, Wright Patterson AFB, OH 45433 USA. RP Byczkowski, JZ (reprint author), TN & Associates Inc, 270 Northland Blvd,Suite 208, Cincinnati, OH 45246 USA. NR 36 TC 3 Z9 3 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 1095-6670 J9 J BIOCHEM MOL TOXIC JI J. Biochem. Mol. Toxicol. PY 1999 VL 13 IS 3-4 BP 205 EP 214 PG 10 WC Biochemistry & Molecular Biology; Toxicology SC Biochemistry & Molecular Biology; Toxicology GA 231MM UT WOS:000082314400011 PM 10098906 ER PT J AU Lubin, B Fiedler, ER Van Whitlock, R AF Lubin, B Fiedler, ER Van Whitlock, R TI Predicting discharge from airforce basic training by pattern of affect SO JOURNAL OF CLINICAL PSYCHOLOGY LA English DT Article ID ADJECTIVE CHECK LIST; VALIDITY; MOOD AB We compared the efficacy of the state form of the MAACL-R (Zuckerman & Lubin. 1985) in predicting success in Air Force basic training. Results of discriminant functions analyses showed that the Anxiety. Depression. Hostility. Positive Affect, and Sensation Seeking scales of the state MAACL-R efficiently predicted success in basic training The need to incorporate state measures into studies of prediction is discussed. (C) 1999 John Wiley & Sons. Inc. C1 Univ Missouri, Kansas City, MO 64110 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. RP Lubin, B (reprint author), 5305 Holmes St, Kansas City, MO 64110 USA. NR 31 TC 12 Z9 12 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0021-9762 J9 J CLIN PSYCHOL JI J. Clin. Psychol. PD JAN PY 1999 VL 55 IS 1 BP 71 EP 78 DI 10.1002/(SICI)1097-4679(199901)55:1<71::AID-JCLP7>3.0.CO;2-I PG 8 WC Psychology, Clinical SC Psychology GA 157GY UT WOS:000078054300007 PM 10100833 ER PT J AU Meink, TE Huybrechts, S Ganley, J Shen, MHH AF Meink, TE Huybrechts, S Ganley, J Shen, MHH TI The effect of varying thickness on the buckling of orthotropic plates SO JOURNAL OF COMPOSITE MATERIALS LA English DT Article AB Although stability failure of constant thickness plates is a fairly well understood problem, buckling of plates with varying thickness has seen little research. This is not a common problem, but buckling of varying thickness plates does occur, as in the case of Advanced Grid Stiffened structures. These structures are characterized by lattices of rigidly connected rib stiffeners. While real-world Advanced Grid Stiffened structure ribs are modeled as orthotropic plates, they often have complex cross-sections (i.e., varying thickness). Unfortunately, failure analysis techniques for these ribs have been limited to rectangular cross-sections. To address this shortcoming, a buckling theory is presented for orthotropic plates of varying thickness. Orthotropic plates with both linear and hourglass thickness variations are considered. These are common grid structure cross-section geometries resulting from existing manufacturing processes. For both geometries, results are given that allow designers to predict how these plates will behave, relative to a constant thickness plate, for a variety of material properties and plate aspect ratios. C1 USAF, Space Vehicles Directorate, Res Lab, Kirtland AFB, NM 87117 USA. Ohio State Univ, Columbus, OH 43210 USA. RP Huybrechts, S (reprint author), USAF, Space Vehicles Directorate, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 10 TC 0 Z9 1 U1 0 U2 0 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 1999 VL 33 IS 11 BP 1048 EP 1061 PG 14 WC Materials Science, Composites SC Materials Science GA 217BF UT WOS:000081478900006 ER PT J AU Calcaterra, JR Mall, S Ruiz, A AF Calcaterra, JR Mall, S Ruiz, A TI Residual strength degradation of cross-ply titanium matrix composite due to elevated temperature SO JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH LA English DT Article DE titanium; composite; metal matrix composite; elevated temperature; fatigue; silicon carbide ID FATIGUE; MECHANISMS AB This study investigates the residual strength degradation of cross-ply, SCS-6/Ti-15-3 titanium matrix composite (TMC) due to elevated temperature fatigue. To accomplish this, several specimens were cycled at 427 degrees C to certain fractions of their expected fatigue lives, then monotonically loaded to failure. Fatigue tests were conducted in both load-control mode with a load ratio (R-sigma) of 0.05 and strain-control mode with a strain ratio (R-epsilon) of -1. Maximum stresses in the load-controlled tests were 300 and 450 MPa with frequencies of 5 and 10 Hz, respectively. The strain amplitudes ranged from 0.25 to 0.4% in the strain-controlled tests. Rather than being conducted at a constant frequency, these tests were performed at a strain rate of 0.1% per s. Various mechanical responses during cycling are discussed and compared fur the load-controlled and strain-controlled tests. After failure, specimens were sectioned and studied usings both optical and scanning electron microscopy. Residual strength data were then correlated to the amount and type of each damage mechanism. It was found that the residual strength degradation in cross-ply laminate, when exposed to different fatigue conditions, correlates together with the fraction of the cyclic life left in the composite. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, ENY, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, ENY, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Calcaterra, JR (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, ENY, Bldg 640,2950 P St, Wright Patterson AFB, OH 45433 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 PU AMER SOC TESTING MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DR, W CONSHOHOCKEN, PA 19428-2959 USA SN 0884-6804 J9 J COMPOS TECH RES JI J. Compos. Technol. Res. PD JAN PY 1999 VL 21 IS 1 BP 16 EP 24 PG 9 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 159EQ UT WOS:000078159200002 ER PT J AU Tomasic, B Cohen, E Sivaprasad, K AF Tomasic, B Cohen, E Sivaprasad, K TI Electric and magnetic current sources in infinite and semi-infinite spaces-expressions for the radiated fields in cylindrical coordinates SO JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS LA English DT Article AB Expressions are derived for the electromagnetic fields due to a circular cylindrical axially-directed electric current source, a radial electric ring source, and magnetic frill in free space and above an infinite ground plane. The expressions are valid everywhere in space including the source region. The fields are given in cylindrical coordinates, and the results are applicable, among others, to the analysis of coaxially-fed cylindrical antennas. C1 USAF, Res Lab, Sensors Directorate, Electromagnet Technol Div, Hanscom AFB, MA 01731 USA. RP Tomasic, B (reprint author), USAF, Res Lab, Sensors Directorate, Electromagnet Technol Div, 31 Grenier St, Hanscom AFB, MA 01731 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU VSP BV PI ZEIST PA PO BOX 346, 3700 AH ZEIST, NETHERLANDS SN 0920-5071 J9 J ELECTROMAGNET WAVE JI J. Electromagn. Waves Appl. PY 1999 VL 13 IS 5 BP 599 EP 627 DI 10.1163/156939399X01041 PG 29 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 204NE UT WOS:000080769800002 ER PT J AU Valtier, S Cody, JT AF Valtier, S Cody, JT TI Metabolic production of amphetamine following administration of clobenzorex SO JOURNAL OF FORENSIC SCIENCES LA English DT Article; Proceedings Paper CT 50th Annual Meeting of the American-Academy-of-Forensic-Sciences CY FEB 13, 1998 CL SAN FRANCISCO, CALIFORNIA SP Amer Acad Forens Sci DE forensic science; clobenzorex; GC/MS; enantiomer analysis; amphetamine; metabolism; anorectic drug; precursor drug; Asenlix ID CHROMATOGRAPHY MASS-SPECTROMETRY AB Many of the anorectic drugs that are metabolized to amphetamine and/or methamphetamine pose significant concerns in the interpretation of amphetamine-positive drug testing results. One of these drugs-clobenzorex-has been shown to produce amphetamine. Thirty milligrams of clobenzorex hydrochloride, in the from of a single Asenlix capsule (Roussel, Mexico), were administered orally to five human volunteers with no history of amphetamine, methamphetamine or clobenzorex use. Following administration, urine samples (total void volume) were collected an lib for seven days and pH, specific gravity and creatinine values were determined. To determine the excretion profile of amphetamine and parent drug, samples were extracted, derivatized, and analyzed by gas chromatography/mass spectrometry (GC/MS) using a standard amphetamine procedure with additional monitoring of ions at m/z 91, 118, 125 and 364 for the detection of clobenzorex. Peak concentrations of amphetamine were detected at 4 to 19 h postdose and ranged from approximately 715 to 2474 ng/mL amphetamine. Amphetamine could be detected (>5 ng/mL) in the urine in one subject for up to 116 h postdose. GC/MS was also used to determine the enantiomeric composition of the metabolite, amphetamine. This analysis revealed the metabolically derived amphetamine was only the d-enantiomer. This differs from previous literature which indicates clobenzorex is the racemic N-orthochlorobenzyl derivative of amphetamine. C1 Wilford Hall USAF Med Ctr, Clin Res Squadron, Lackland AFB, TX 78236 USA. RP Valtier, S (reprint author), Wilford Hall USAF Med Ctr, Clin Res Squadron, 1255 Wilford Hall Loop, Lackland AFB, TX 78236 USA. NR 6 TC 10 Z9 10 U1 0 U2 1 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 1999 VL 44 IS 1 BP 17 EP 22 PG 6 WC Medicine, Legal SC Legal Medicine GA 293AV UT WOS:000085830100003 PM 9987865 ER PT J AU Aguero, VM Burke, WJ Gilchrist, BE Stone, NH Gentile, LC Williams, SD Cooke, DL Thompson, DC Bonifazi, C Lebreton, JP AF Aguero, VM Burke, WJ Gilchrist, BE Stone, NH Gentile, LC Williams, SD Cooke, DL Thompson, DC Bonifazi, C Lebreton, JP TI Current collection at the shuttle orbiter during the tethered satellite system tether break SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID TSS-1 AB We present measurements of currents, orbiter potentials, and plasma spectra during high-voltage arcing coincident with the tether break event on the Tethered Satellite System reflight. In addition to the unexpectedly high tether currents observed, plasma spectra indicate the presence of ion and electron populations with broad energy ranges. These data were used, in combination with satellite and orbiter current collection models to investigate the circuit behavior of the system's components. We find that arcing at the lower end of,the tether supported the current flow in the tether during each phase of the break event, but with different mechanisms dominant depending on the location of the break paint. With the break point inside deployer control structures, current arced to the orbiter ground, charging it to high negative potentials and allowing secondary ionization of neutral molecules near orbiter conducting surfaces. The most likely source of these neutrals is air trapped inside the tether at I atm of pressure that escaped through the hole in the tether insulation. When the break point was exposed to the exterior environment the tether current arced directly to the plasma. As long as the break point remained near the orbiter, the collection of electrons by conducting surfaces caused it to float at a low level of negative charging. The source of the energetic elections detected in the payload bay remains uncertain. However, they can only have come from a region within the sheath that was more negatively charged than the orbiter's conducting surfaces. C1 SRI Int, Menlo Park, CA 94025 USA. Agenzia Spaziale Italiana, I-00198 Rome, Italy. USAF, Res Lab, Hanscom AFB, MA 01731 USA. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA. Space Phys Res Lab, Ann Arbor, MI 48109 USA. European Space Agcy, European Space Res & Technol Ctr, NL-2200 AG Noordwijk, Netherlands. NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35812 USA. Utah State Univ, Ctr Atmospher & Space Sci, SER218D, Logan, UT 84322 USA. Stanford Univ, Star Lab, Stanford, CA 94305 USA. RP Aguero, VM (reprint author), SRI Int, 333 Ravenswood Ave,MS-408-95, Menlo Park, CA 94025 USA. EM vaguero@unix.-sri.com; burke@plh.af.mil; gilchrst@eecs.-umich.edu; nobie.stone@-msfc.nasa.gov; gentile@plh.af.mil; scott@nova.stanford.edu; cooke@pepper.plh.af.mil; thompson@demise.cass.usu.edu; bonifazi@asirom.rm.asi.it; jlebreto@estec.esa.nl NR 18 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JAN 1 PY 1999 VL 104 IS A1 BP 105 EP 114 DI 10.1029/1998JA900008 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000009 ER PT J AU Papitashvili, VO Rich, FJ Heinemann, MA Hairston, MR AF Papitashvili, VO Rich, FJ Heinemann, MA Hairston, MR TI Parameterization of the Defense Meteorological Satellite Program ionospheric electrostatic potentials by the interplanetary magnetic field strength and direction SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID LATITUDE ELECTRIC POTENTIALS; CONVECTION PATTERN; MODEL; CURRENTS; WEATHER; SPACE; NORTHERN AB In this study we applied a linear regression analysis technique to the interplanetary magnetic field (IMF) data and the ionospheric electrostatic potentials obtained from thermal ion drift measurements made by the Defense Meteorological Satellite Program (DMSP) satellites F8 and F10-F13 in 1993-1996. The ionospheric potentials are binned by, every 1 degrees of the corrected geomagnetic latitude and 0.5 hour of magnetic local time over both the northern and southerh polar regions. The regression analyses are applied to the DMSP data in each bin in a Similar way to what was done with the ground magnetometer data in the IZMIRAN Electrodynamic Model (IZMEM). This allowed us to parameterize the DMSP ionospheric potentials by the IMF strength and direction, as well as to recalibrate the IZMEM model against experimental satellite data. From the analysis it is calculated that the "background" cross-polar potential drop estimated from DMSP data equals similar to 33 kV if IMF approximate to 0. The calculated ionospheric potential responses to changes in the southward and northward IMF components are 11.5 kV/nT and -5.0 kV/nT, respectively. C1 Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA. Univ Texas, William B Hanson Ctr Space Sci, Richardson, TX 75080 USA. USAF, Res Lab, Bedford, MA 01731 USA. Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA. RP Papitashvili, VO (reprint author), Univ Michigan, Space Phys Res Lab, 2455 Hayward St, Ann Arbor, MI 48109 USA. OI Papitashvili, Vladimir/0000-0001-6955-4894; Hairston, Marc/0000-0003-4524-4837 NR 38 TC 40 Z9 40 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JAN 1 PY 1999 VL 104 IS A1 BP 177 EP 184 DI 10.1029/1998JA900053 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000014 ER PT J AU Basu, B Coppi, B AF Basu, B Coppi, B TI Relevance of plasma and neutral wind velocities to the topology and the excitation of modes for the onset of the equatorial spread F SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID DRIFTS; IRREGULARITIES; INSTABILITY AB A theoretical model for the onset of the equatorial spread F (ESF) is introduced that considers all the effects of the electric fields that are present together with the effects of the neutral wind velocity, of gravity, and of the density gradient. These impose well-defined topological constraints on the modes that can be excited. The horizontal (east-west) ion velocity is shown to be one of the key factors for the intrinsic vertical localization of modes that are driven unstable by the effective vertical gravity (including the E field contribution). The thickness of the layer of localization is related to the Vertical gradient of the ion horizontal velocity, of the neutral wind velocity, and of the ion-neutral collision frequency. The "horizontal gravity" resulting from the difference between the horizontal ion and neutral velocities is shown to not be a driving factor for the instability, under realistic conditions when the eastward electric field is included in the analysis, but to have an important influence on the mode topology (vertical profile). An explicit analytical solution is found for the relevant dispersion equation, which includes, in particular, the contribution of a vertical ion velocity. The mode vertical profile under conditions that are shown to be realistic is found. It is suggested that the necessary conditions for the intrinsic localization of the modes determine the onset of the ESF. The mode ballooning structure, along the magnetic field, including the effect of the plasma finite resistivity is also described. C1 USAF, Res Lab, VSBP, Hanscom AFB, MA 01731 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. RP Basu, B (reprint author), USAF, Res Lab, VSBP, 29 Ransolph Rd, Hanscom AFB, MA 01731 USA. NR 15 TC 9 Z9 9 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD JAN 1 PY 1999 VL 104 IS A1 BP 225 EP 231 DI 10.1029/1998JA900069 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 158LB UT WOS:000078116000018 ER PT J AU Gilbreath, GC Schumacher, PW Davis, MA Lydick, ED Anderson, JM AF Gilbreath, GC Schumacher, PW Davis, MA Lydick, ED Anderson, JM TI Evaluation of the Naval Space surveillance fence performance using satellite laser ranging SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article AB An experiment is described in which the performance of the Naval Space Command Fence Receiver Suite is evaluated using satellite laser ranging. Fence measurement accuracy and precision is presently assessed based on cataloged orbits, which are not sufficiently accurate for rigorous calibration and trend identification. Satellite laser ranging is a well-known high-precision data type, which can provide submeter reference positions routinely. Two methods of sensor evaluation are investigated. One is an ephemeris-based approach, where a truth reference orbit is determined from laser ranging data from a number of different satellites at different altitudes. Fence-based residuals are then computed from this truth, The second is a geometric method, which computes satellite positions directly using ranging data and angle data from the telescope. A mathematical treatment of the geometric dilution of precision for both methods is included in the discussion, The overall experiment showed that the fence sensor suite is operating to within 14-17 times its noise floor of 10 mu rad at zenith, We believe that this is the most extensive measurement of the fence performance utilizing an external and independent data type, and due to the precision of the data type, its overall response and error trends are identified. C1 USN, Res Lab, Electroopt Technol Sect, Washington, DC 20375 USA. USN, Space Command, Informat Syst Div, Anal & Software Branch, Dahlgren, VA 22448 USA. Allied Signal Aerosp Co, Earth Sci & Laser Technol, Lanham, MD 20706 USA. USN, Space Command, Informat Syst Div, Anal & Software Branch, Dahlgren, VA 22448 USA. USAF, Res Lab, Starfire Opt Range, LIG, Albuquerque, NM 87177 USA. RP Gilbreath, GC (reprint author), USN, Res Lab, Electroopt Technol Sect, Code 8123, Washington, DC 20375 USA. NR 4 TC 5 Z9 5 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091-4344 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD JAN-FEB PY 1999 VL 22 IS 1 BP 149 EP 155 DI 10.2514/2.4361 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 157WB UT WOS:000078083700017 ER PT J AU Griffin, SF Denoyer, KK Das, A AF Griffin, SF Denoyer, KK Das, A TI Passive vibroacoustic isolation for payload containers SO JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES LA English DT Article AB This paper presents analysis and experimental results which examine key issues related to passive vibroacoustic isolation for container type structures. The key noise reduction principle examined is the passive application of a characteristic impedance mismatch in conjunction with a vibration isolation suspension system to limit structural transmission. The characteristic impedance mismatch is created by imposing a near vacuum condition between partitions of a container structure. Unlike active boundary control techniques, this approach is insensitive to the grazing angle of the source acoustics, is simple, and avoids technology challenges such as the need to develop efficient large stroke actuators. The analysis for this problem is performed by extending Fahy's double-leaf partition model. Using the extended model, numerical simulations are conducted to study the effect of various design parameters on acoustic transmission. Guidelines developed from this study are then used to construct an experiment to show the viability of the concept. The experiment demonstrates that at least a 19 dB reduction in sound pressure level (SPL) may be achieved, with a modest level of vacuum. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Griffin, SF (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 7 TC 9 Z9 10 U1 0 U2 0 PU TECHNOMIC PUBL CO INC PI LANCASTER PA 851 NEW HOLLAND AVE, BOX 3535, LANCASTER, PA 17604 USA SN 1045-389X J9 J INTEL MAT SYST STR JI J. Intell. Mater. Syst. Struct. PD JAN PY 1999 VL 10 IS 1 BP 83 EP 87 DI 10.1106/LPH9-RGUP-T2B3-VK4N PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 284XC UT WOS:000085357300008 ER PT J AU Premachandra, JK Kumudinie, C Mark, JE AF Premachandra, JK Kumudinie, C Mark, JE TI Preparation and properties of some hybrid aerogels from a sulfopolybenzobisthiazole-silica composite SO JOURNAL OF MACROMOLECULAR SCIENCE-PURE AND APPLIED CHEMISTRY LA English DT Article DE aerogels; organic-inorganic hybrid materials; polymer-modified ceramics; sulfopolybenzobisthiazole; high-temperature polymers ID MODIFIED SIO2 AEROGELS; ELASTIC PROPERTIES AB Aerogels were prepared so as to have a hybrid structure, by carrying out the supercritical drying process on composites consisting of an in situ generated silica network as the inorganic phase and a high-temperature polymer as the organic phase. The goal was to maintain the best properties of both components, for example, decreasing the brittleness of the ceramic phase by introducing a polymeric phase. A polybenzobisthiazole of very high thermal stability, with sulfonation to increase its reactivity, was chosen for the organic phase, and it was bonded to the silica phase by a silane coupling agent. A range of silica/polymer compositions were investigated, and the resulting materials were characterized in terms of their moduli and ultimate properties in compression. Increase in the amount of polymer present decreased the moduli but increased deformabilities, yielding relationships that should be useful in the design of aerogels of optimized properties. Values of Poisson's ratio were also determined and used to estimate longitudinal sound velocities, which can be important in some applications of aerogel materials in general. C1 Univ Cincinnati, Dept Chem, Cincinnati, OH 45221 USA. Univ Cincinnati, Polymer Res Ctr, Cincinnati, OH 45221 USA. USAF, Polymer Branch, RL, MLBP, Wright Patterson AFB, OH 45433 USA. RP Mark, JE (reprint author), Univ Cincinnati, Dept Chem, Cincinnati, OH 45221 USA. EM markje@email.uc.edu NR 35 TC 4 Z9 4 U1 0 U2 9 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 1060-1325 J9 J MACROMOL SCI PURE JI J. Macromol. Sci.-Pure Appl. Chem. PY 1999 VL A36 IS 1 BP 73 EP 83 DI 10.1081/MA-100101517 PG 11 WC Polymer Science SC Polymer Science GA 168EG UT WOS:000078678000004 ER PT J AU Lear, MH Sankar, BV AF Lear, MH Sankar, BV TI Optimizing energy absorption in multi-layered materials through controlled delamination SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID COMPOSITE; BEHAVIOR; DAMAGE AB The intent of this paper is to investigate the mechanics of delamination growth in an isotropic, ideally-brittle layered material under an impact load and to present guidelines for the design of more energy absorbent structures. Using a finite element model, both two- and three-layered configurations are considered. Prompted by the results from this model, closed-form solutions for the interlaminar shear strength and the interfacial fracture toughness corresponding to maximum energy absorption are derived for the two-layered laminate. These solutions were used to develop guidelines for the optimal design of two- and three-layered laminates. (C) 1999 Kluwer Academic Publishers. C1 Univ Florida, Gainesville, FL 32611 USA. RP Lear, MH (reprint author), 46th Test Wing, Eglin AFB, FL 32542 USA. OI Sankar, Bhavani/0000-0002-4556-1982 NR 11 TC 4 Z9 4 U1 0 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PY 1999 VL 34 IS 17 BP 4181 EP 4191 DI 10.1023/A:1004630230780 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 223DY UT WOS:000081826200011 ER PT J AU Miglionico, CJ Stein, C Trillo, EA Murr, LE AF Miglionico, CJ Stein, C Trillo, EA Murr, LE TI Microstructural evolution in polycrystalline silver used as a source of atomic oxygen SO JOURNAL OF MATERIALS SCIENCE LETTERS LA English DT Article C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. Univ Texas, Dept Met & Mat Engn, El Paso, TX 79968 USA. RP Miglionico, CJ (reprint author), USAF, Res Lab, Phillips Res Site, Kirtland AFB, NM 87117 USA. OI Murr, Lawrence/0000-0001-5942-8376 NR 16 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0261-8028 J9 J MATER SCI LETT JI J. Mater. Sci. Lett. PD JAN 1 PY 1999 VL 18 IS 1 BP 1 EP 7 DI 10.1023/A:1006600720958 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 173GH UT WOS:000078972400001 ER PT J AU Hughes, WG Houston, GD Savage, MG AF Hughes, WG Houston, GD Savage, MG TI Slow-growing midline submental mass SO JOURNAL OF ORAL AND MAXILLOFACIAL SURGERY LA English DT Article ID THYROGLOSSAL DUCT CYST; SUBMANDIBULAR-GLAND; PLUNGING RANULA; MUCOCELE C1 Wright Patterson Med Ctr, Dept Oral & Maxillofacial Surg, Wright Patterson AFB, OH USA. Univ Oklahoma, Hlth Sci Ctr, Coll Dent, Dept Oral & Maxillofacial Surg, Oklahoma City, OK USA. Univ Oklahoma, Hlth Sci Ctr, Coll Med, Dept Oral & Maxillofacial Surg, Oklahoma City, OK USA. Univ Colorado, Hlth Sci Ctr, Sch Dent, Div Oral & Maxillofacial Surg, Denver, CO USA. RP Hughes, WG (reprint author), 74 DS SGDDS,4881 Sugar Maple Dr, Wright Patterson AFB, OH 45433 USA. NR 21 TC 3 Z9 3 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0278-2391 J9 J ORAL MAXIL SURG JI J. Oral Maxillofac. Surg. PD JAN PY 1999 VL 57 IS 1 BP 61 EP 65 DI 10.1016/S0278-2391(99)90635-3 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 153NV UT WOS:000077839900018 PM 9915398 ER PT J AU Nadon, LJJP Kramer, SC King, PI AF Nadon, LJJP Kramer, SC King, PI TI Multidisciplinary optimization in conceptual design of mixed-stream turbofan engines SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB Conceptual engine design is currently done essentially using a trial-and-error process based on the experience of engineers. This paper presents an alternative approach using multidisciplinary optimization to automate the conceptual design phase and ensure that an optimal design is reached. A robust integrated computer program was created to find the values of eight basic engine parameters that minimized fuel usage over a given mission. Because of the character of the objective function, a new approach was devised incorporating a genetic algorithm with a switch to a gradient-based algorithm to refine the design. The new procedure was used to optimize the engine design for a conceptual short-range interceptor. The process is general, however, and can be applied to a wide variety of missions and aircraft. C1 Natl Def Headquarters, Directorate Tech Airworthiness 3 4 6, Ottawa, ON K1K 0K2, Canada. USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Nadon, LJJP (reprint author), Natl Def Headquarters, Directorate Tech Airworthiness 3 4 6, Major Gen George R Pearkes Bldg, Ottawa, ON K1K 0K2, Canada. NR 9 TC 2 Z9 2 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD JAN-FEB PY 1999 VL 15 IS 1 BP 17 EP 22 DI 10.2514/2.5412 PG 6 WC Engineering, Aerospace SC Engineering GA 159EU UT WOS:000078159500003 ER PT J AU Fabian, MK Jumper, EJ AF Fabian, MK Jumper, EJ TI Rearward forcing of an unsteady compressible cascade SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB Phase-locked, steady and unsteady, surface pressure measurements were made on the vanes of a compressible cascade, for inlet Mach numbers up to similar to 0.7. The cascade vanes were production hardware stator vanes from an AlliedSignal F109 turbofan engine. Data are presented from which it may be concluded that the cascade produces reasonably good two-dimensional flow through the vane row. Unsteady forcing within the cascade can be produced either upstream or downstream of the vane row. In the present paper, how unsteadiness in the cascade was produced using shedding from circular cylinders positioned at a distance equal to 80% vane chords downstream of the vane row This rearward forcing of the vane row resulted in unsteady surface pressures of the same order as those produced in similar experiments with forward forcing. Decomposition of the ensembled, phase-locked, pressure-response signals for rearward forcing provided insight into both the nature of the unsteady disturbance and the physics of its propagation within the vane row. C1 Univ Notre Dame, Hessert Ctr Aerosp Res, Dept Aerosp & Mech Engn, Notre Dame, IN 46556 USA. RP Fabian, MK (reprint author), USAF Acad, Dept Aeronaut, Colorado Springs, CO 80840 USA. RI Jumper, Eric/A-9856-2013 NR 17 TC 3 Z9 3 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD JAN-FEB PY 1999 VL 15 IS 1 BP 23 EP 30 DI 10.2514/2.5413 PG 8 WC Engineering, Aerospace SC Engineering GA 159EU UT WOS:000078159500004 ER PT J AU Baron, DT Miller, TC Liu, CT AF Baron, DT Miller, TC Liu, CT TI Subcritical crack growth in a composite solid propellant SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article DE linear elastic fracture mechanics; LEFM; plane stress; composite solid propellant; crack growth; crack growth rate; Mode 1 stress intensity factor; crack growth resistance curve; thickness effect AB Uniaxial tension tests using a strain rate of 0.04 in./in./min. are performed on rectangular smooth and single edge-notched specimens of varying thicknesses for a composite solid propellant. Stress-strain, crack growth, crack growth rate and crack growth resistance data are provided. Thickness effects and the mechanism of crack growth are described. Methods of calculation are explained for the crack growth rate and the Mode 1 stress intensity factor. A model is developed for the crack stable growth rate as a function of the stress intensity factor. C1 Raytheon STX Corp, Edwards AFB, CA 93524 USA. USAF, Res Lab, Edwards AFB, CA 93524 USA. RP Baron, DT (reprint author), Raytheon STX Corp, Edwards AFB, CA 93524 USA. NR 8 TC 2 Z9 3 U1 1 U2 3 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0731-6844 J9 J REINF PLAST COMP JI J. Reinf. Plast. Compos. PY 1999 VL 18 IS 3 BP 233 EP 250 PG 18 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 172ZF UT WOS:000078955700004 ER PT J AU Genidy, MS Madhukar, MS Russell, JD AF Genidy, MS Madhukar, MS Russell, JD TI An investigation of cure induced stresses in law cure temperature thermoset polymer composites SO JOURNAL OF REINFORCED PLASTICS AND COMPOSITES LA English DT Article DE cure cycle; low cure resins; optimization; residual stresses; stress relaxation; and thermosets AB Low temperature thermal curing resins (such as LTM-45 ELD and X343-59) are being considered by the aerospace industry for developing prototype parts. By curing at low temperatures, the parts can be cured outside of the autoclave. Therefore, expensive autoclave hardened tooling is not required. Tooling materials such as wood and foam can be used instead. This will dramatically reduce the cost of producing prototype parts. The effect. of the standard cure cycles on the cure induced stresses in composites containing such resins is not characterized yet. Most of the cure induced stresses are developed after the polymer reaches the gel point. Any subsequent polymer volume change produces fiber stresses. Stress relaxation acts to reduce stresses developed during cure. Relaxation time increases significantly after the polymer is gelled and thus stress relaxation becomes less effective to reduce cure induced fiber stresses. A closed loop feedback control system has been developed to monitor the cure induced fiber stresses and to determine cure cycles with less residual stresses. In this system, a polymer is cured along a given length of a pretensioned fiber. The cure induced stresses are determined by measuring the fiber tension change. This method was applied to LTM-45 ELD and X343-59 resins during standard two stage cure cycles and during a typical autoclave cure cycle used for 3501-6 epoxy. The cure induced fiber stresses were monitored during these cycles. In addition, the feedback control was used to determine modified cure cycles to reduce these stresses. C1 Univ Tennessee, Dept Aerosp Engn Mech & Engn Sci, Knoxville, TN 37996 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Madhukar, MS (reprint author), Univ Tennessee, Dept Aerosp Engn Mech & Engn Sci, Knoxville, TN 37996 USA. RI Madhukar, Madhu/P-4365-2015 NR 23 TC 6 Z9 6 U1 0 U2 2 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 1999 VL 18 IS 14 BP 1304 EP 1321 PG 18 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 247HV UT WOS:000083216100003 ER PT J AU Zuber, ME Towne, MC Chen, AJ Bertin, JJ Butler, RJ AF Zuber, ME Towne, MC Chen, AJ Bertin, JJ Butler, RJ TI Aerothermodynamic environment for a generic missile SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB There are a variety of computer codes of varying degrees of rigor that can be used by the designers of highspeed missile systems to define the aerothermodynamic environment at flight conditions, It is assumed that the how models and the numerical algorithms used in these codes have been validated by their developers. However, the users of such codes must exercise them against a quality database, gaining knowledge of the intricacies in the use of such codes and calibrating the range of conditions over which the code can be used to predict specific parameters that are important to the design objectives without necessarily verifying that all of the features of the flow are correctly modeled, Forces and moments, surface pressures, surface temperatures, and flow-visualization photographs have been obtained in the Tri-Sonic Wind Tunnel at the US. Air Force Academy at Mach 4.28, When comparing the flowfield parameters computed using state-of-the-art codes with the corresponding experimental parameters, streamwise oscillations were observed in the computed pressure distribution on the windward surface of the missile at angle of attack, These anomalous results were eliminated by modifying the grid to cluster points for capturing the bow shock wave. C1 USAF Acad, Dept Aeronaut, Colorado Springs, CO 80840 USA. RP Zuber, ME (reprint author), USAF Acad, Dept Aeronaut, Colorado Springs, CO 80840 USA. NR 21 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD JAN-FEB PY 1999 VL 36 IS 1 BP 44 EP 52 DI 10.2514/2.3431 PG 9 WC Engineering, Aerospace SC Engineering GA 166LJ UT WOS:000078577800003 ER PT J AU Josyula, E AF Josyula, E TI Computational simulation improvements of supersonic high-angle-of-attack missile flows SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA 36th Aerospace Sciences Meeting CY JAN 12-15, 1998 CL RENO, NEVADA SP Amer Inst Aeronaut & Astronaut ID NAVIER-STOKES EQUATIONS; 2-EQUATION MODEL; TURBULENCE; VORTEX AB A numerical simulation is presented for the steady-state flow over a missile body configuration for supersonic Mach number at incidence. The missile has a diameter d of 0.09398 m and a length of 13d, Flow conditions specified are Mach 2.5, angle of attack 14 deg, and Reynolds number 1.23 x 10(6) based on the diameter of afterbody to match experimental conditions. The three-dimensional Navier-Stokes equations in mass-averaged form were numerically integrated using both central and upwind difference methods, implicit Beam and Warming algorithm with the two-equation k-epsilon turbulence model to provide closure of the system of equations. The upwind method captured the crossflow shock better, and the central difference method predicted the vortex shape and strength better. Modifications to the two-equation turbulence model, which limited the production of eddy viscosity for vortical Bows, were implemented to assess the improvement in accuracy. The modifications improved prediction of the vortical shape and strength and showed improvements in the surface pressure predictions due to stronger primary and secondary vortices. A grid resolution study to examine the effects of the modifications to the k-epsilon turbulence model was conducted. The grid study indicated that the improvements in the shear layer resolution and vortex core predictions were better when refinement was made in the body normal and circumferential directions. C1 USAF, Res Lab, Computat Sci Branch, Wright Patterson AFB, OH 45433 USA. RP Josyula, E (reprint author), USAF, Res Lab, Computat Sci Branch, Wright Patterson AFB, OH 45433 USA. NR 19 TC 6 Z9 8 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD JAN-FEB PY 1999 VL 36 IS 1 BP 59 EP 66 DI 10.2514/2.3433 PG 8 WC Engineering, Aerospace SC Engineering GA 166LJ UT WOS:000078577800005 ER PT J AU Belue, LM Bauer, KW AF Belue, LM Bauer, KW TI Designing experiments for single output multilayer perceptrons SO JOURNAL OF STATISTICAL COMPUTATION AND SIMULATION LA English DT Article DE neural networks; experimental design; nonlinear regression; multilayer perceptron AB Where should a researcher conduct experiments to provide training data for a multilayer perceptron? This question is investigated and a statistical method for selecting optimal experimental design points for multilayer perceptrons is introduced. Two-class discrimination problems are examined in which the multilayer perceptron is viewed as a univariate nonlinear regression model. A selection criterion is developed based on thr volume of the joint confidence ellipsoid for the weights in a multilayer perceptron. The criterion is minimized to find optimal design points. Minimization is accomplished using Powell's algorithm when the feature space is continuous and a discrete exchange algorithm when the feature space is discrete. An example is used to demonstrate: the superiority of optimally selected design points over randomly chosen points and points chosen in a grid pattern. In addition, two measures are developed to rank the design points in terms of their relative importance. C1 USAF, Inst Technol, Dept Operat Sci, Wright Patterson AFB, OH 45433 USA. USAF, Personnel Operat Agcy, Wright Patterson AFB, OH 45433 USA. RP Bauer, KW (reprint author), USAF, Inst Technol, Dept Operat Sci, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 24 TC 0 Z9 0 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 0094-9655 J9 J STAT COMPUT SIM JI J. Stat. Comput. Simul. PY 1999 VL 64 IS 4 BP 301 EP 325 DI 10.1080/00949659908811983 PG 25 WC Computer Science, Interdisciplinary Applications; Statistics & Probability SC Computer Science; Mathematics GA 285JM UT WOS:000085386000002 ER PT J AU John, R Zawada, LP Kroupa, JL AF John, R Zawada, LP Kroupa, JL TI Stresses due to temperature gradients in ceramic-matrix-composite aerospace components SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID EXPANSION AB Ceramic-matrix composites (CMCs) are being considered as replacement materials for divergent flaps and seals in advanced aerospace turbine engines. During ser,ice, these components are subjected to severe temperature gradients across the width of the flaps. This paper discusses an analytical procedure to estimate the stresses generated in the CMC naps due to the temperature gradients. The analytical procedure can be used for a material with nonlinear temperature-dependent stress-strain behavior. This procedure mas used to predict the thermal stresses in four candidate CMC systems due to temperature gradients. The thermal stresses along the edges typically exceed the proportional limit, and sometimes the fatigue limit of the CMC. C1 USAF, Mat & Mfg Directorate, AFRL, MLLN, Wright Patterson AFB, OH 45433 USA. RP John, R (reprint author), USAF, Mat & Mfg Directorate, AFRL, MLLN, Wright Patterson AFB, OH 45433 USA. NR 29 TC 16 Z9 16 U1 0 U2 4 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JAN PY 1999 VL 82 IS 1 BP 161 EP 168 PG 8 WC Materials Science, Ceramics SC Materials Science GA 158UC UT WOS:000078134500021 ER PT J AU Matson, LE Hecht, N AF Matson, LE Hecht, N TI Microstructural stability and mechanical properties of directionally solidified alumina/YAG eutectic monofilaments SO JOURNAL OF THE EUROPEAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT Meeting on New Developments in High Temperature Materials CY AUG 12-15, 1998 CL ISTANBUL, TURKEY DE Al2O3; coarsening; creep; fibers; monofilaments; YAG ID YTTRIUM-ALUMINUM-GARNET; CERAMIC FIBERS; DEFORMATION; BEHAVIOR; SAPPHIRE; FRACTURE; YAG; TEMPERATURE AB Fiber strength retention and creep currently limit the use of polycrystalline oxide fibers in ceramic matrix composites making it necessary to develop single crystal fibers. Two-phase alumina/YAG single crystal structures in the form of monofilaments show that the room temperature tensile strength increases according to the inverse square root of the microstructure size. Therefore, microstructure stability will play a significant role in determining the 'use temperature' of these fibers along with its creep resistance. In this work, the effects of temperature on microstructural stability and the creep behavior of directionally solidified alumina/YAG eutectic monofilaments weve studied. Microstructural stability experiments were conducted in air from 1200 to 1500 degrees C and creep tests at temperatures of 1400 to 1700 degrees C. Inherent microstructure stability was found to be very good, however, extraneous impurity-induced heterogeneous coarsening was significant above 1400 degrees C. The creep strength of monofilaments with aligned microstructures were superior to ones with low aspect ratio morphologies. Mechanisms for microstructural coarsening and creep behavior ave discussed. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, AFRL,MLLN, WPAFB, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Dayton, OH 45469 USA. RP Matson, LE (reprint author), USAF, AFRL,MLLN, WPAFB, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 67 TC 37 Z9 42 U1 0 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0955-2219 J9 J EUR CERAM SOC JI J. European Ceram. Soc. PY 1999 VL 19 IS 13-14 BP 2487 EP 2501 DI 10.1016/S0955-2219(99)00125-9 PG 15 WC Materials Science, Ceramics SC Materials Science GA 243PE UT WOS:000083005800032 ER PT J AU Leland, QH Ponnappan, R Brown, JR AF Leland, QH Ponnappan, R Brown, JR TI Compatibility test and residual gas analysis on 4130 steel and methanol thermosyphons SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article; Proceedings Paper CT AIAA 32nd Thermophysics Conference CY JUN 23-25, 1997 CL ATLANTA, GEORGIA SP Amer Inst Aeronaut & Astronaut AB Testing has been carried out to determine the material compatibility of methanol and 4130 steel. This fluid/material combination is of interest for rotating heat-pipe applications associated with cooling of electrical generators. Thermal soaking at 150 degrees C of four methanol thermosyphons made of type 4130 steel was accomplished, Two of the thermosyphons have nickel-brazed joints and two have laser-welded joints, The temperature profiles indicated the generation of noncondensable gases (NCGs) in all four thermosyphons for a thermal soak test time exceeding 14,000 h. The analysis showed that the NCG-generation rate accelerated up to 7.4 mu l/h initially and then dropped to a nearly constant rate of 2.5 mu l/h. Three NCG-generating regions were identified: accelerating, decelerating, and stable. The qualitative residual gas analysis using a mass spectrometer after 4000, 8700, and 14,000 h of thermal soak indicated the existence of the NCGs: hydrogen, formaldehyde, methane, and carbon monoxide, The corrosion and oxidation theory-based passivating film growth model and methanol catalytic decomposition model were qualitatively supported by the decelerating and stable regions defined in this experiment. It was also shown that burping is not a viable option to prolong the contaminated heat-pipe's life, Data obtained will provide important information for determination of the life and reliability of a rotating methanol heat pipe made of 4130 steel, and also, for the evaluation of the assembly processes used for fabricating rotating heat pipes. C1 Universal Energy Syst Inc, Dept Mat, Dayton, OH 45432 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Leland, QH (reprint author), YSI Inc, 1700-1725 Brannum Lane, Yellow Springs, OH 45387 USA. NR 11 TC 0 Z9 0 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0887-8722 J9 J THERMOPHYS HEAT TR JI J. Thermophys. Heat Transf. PD JAN-MAR PY 1999 VL 13 IS 1 BP 146 EP 152 DI 10.2514/2.6413 PG 7 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 162TP UT WOS:000078363100019 ER PT J AU Bloch, GS Copenhaver, WW O'Brien, WF AF Bloch, GS Copenhaver, WW O'Brien, WF TI A shock loss model for supersonic compressor cascades SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article ID PREDICTION AB Loss models used in compression system performance prediction codes are often developed from the study of two-dimensional cascades. In this paper compressible fluid mechanics has been applied to the changes in shock geometry that are known to occur with back pressure for unstarted operation of supersonic compressor cascades. This physics-based engineering shock loss model is applicable to cascades with arbitrary airfoil shapes. Predictions from the present method have been compared to measurements and Navier-Stokes analyses of the L030-4 and L030-6 cascades, and very good agreement was demonstrated for unstarted operation. A clear improvement has been demonstrated over preciously published shock loss models for unstarted operation, both in the accuracy of the predictions and in the range of applicability. The dramatic increase in overall loss with increasing inlet flow angle is shown to be primarily the result of increased shock loss, and much of this increase is caused by the detached bow shock. For a given Mach number, the viscous profile loss is nearly constant over the entire unstarted operating range of the cascade, unless a shock-induced boundary layer separation occurs near stall. Shock loss is much more sensitive to inlet Mach number than is viscous profile loss. C1 USAF, Wright Lab, Aero Propuls & Power Directorate, Wright Patterson AFB, OH 45433 USA. Virginia Polytech Inst & State Univ, Dept Mech Engn, Blacksburg, VA 24061 USA. RP Bloch, GS (reprint author), USAF, Wright Lab, Aero Propuls & Power Directorate, Wright Patterson AFB, OH 45433 USA. NR 32 TC 8 Z9 8 U1 0 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD JAN PY 1999 VL 121 IS 1 BP 28 EP 35 PG 8 WC Engineering, Mechanical SC Engineering GA 158UH UT WOS:000078135100004 ER PT J AU Oefelein, MG AF Oefelein, MG TI Disease progression following radical prostatectomy in men with Gleason score 7 tumor - J. I. Epstein, C. R. Pound, A. W. Partin and P. C. Walsh - J. Urol., 160 : 97-101, 1998 SO JOURNAL OF UROLOGY LA English DT Letter C1 SGOSU, Med Grp 74, Wright Patterson AFB, OH 45433 USA. RP Oefelein, MG (reprint author), SGOSU, Med Grp 74, 4881 Sugar Maple Dr, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0022-5347 J9 J UROLOGY JI J. Urol. PD JAN PY 1999 VL 161 IS 1 BP 231 EP 231 DI 10.1016/S0022-5347(01)62114-1 PG 1 WC Urology & Nephrology SC Urology & Nephrology GA 145NL UT WOS:000077377800072 PM 10037411 ER PT J AU Loomer, DC Johnson, SP Diffin, DC DeMaioribus, CA AF Loomer, DC Johnson, SP Diffin, DC DeMaioribus, CA TI Superior mesenteric artery stent placement in a patient with acute mesenteric ischemia SO JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY LA English DT Article DE arteries, mesenteric; mesentery, ischemia ID TRANS-LUMINAL ANGIOPLASTY; PERCUTANEOUS TRANSLUMINAL ANGIOPLASTY; INTESTINAL ANGINA; OCCLUSION C1 Wilford Hall USAF Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Vasc Surg, Lackland AFB, TX 78236 USA. RP Loomer, DC (reprint author), 60 MDTS, SGXQ, 101 Bodin Circle, Travis AFB, CA 94535 USA. NR 15 TC 23 Z9 24 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1051-0443 J9 J VASC INTERV RADIOL JI J. Vasc. Interv. Radiol. PD JAN PY 1999 VL 10 IS 1 BP 29 EP 32 DI 10.1016/S1051-0443(99)70005-9 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging; Peripheral Vascular Disease SC Radiology, Nuclear Medicine & Medical Imaging; Cardiovascular System & Cardiology GA 159TT UT WOS:000078191100005 PM 10872486 ER PT J AU Delaney, DK Grubb, TG Beier, P Pater, LL Reiser, MH AF Delaney, DK Grubb, TG Beier, P Pater, LL Reiser, MH TI Effects of helicopter noise on Mexican spotted owls SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article DE chain saws; disturbance; flush response; helicopters; Mexican spotted owls; noise; response thresholds; sound measurements; Strix occidentalis lucida ID BREEDING BALD EAGLES; RESPONSES; BEHAVIOR; AIRCRAFT AB Military helicopter training over the Lincoln National Forest (LNF) in southcentral New Mexico has been severely limited to protect nesting Mexican spotted owls (Strix occidentalis lucida). To evaluate nesting and nonnesting spotted owl responses to helicopter noise, we measured flush frequency, flush distance, alert behavior, response duration, prey delivery rates, female trips from the nest, and nest attentiveness during manipulated and nonmanipulated periods, 1995-96. Chain saws were included in our manipulations to increase experimental options and to facilitate comparative results. We analyzed stimulus events by measuring noise levels as unweighted one-third-octave band levels, applying frequency weighting to the resultant spectra, and calculating the sound exposure level for total sound energy (SEL) and the 0.5-sec equivalent maximum energy level (LEQ(max 0.5-sec)) for helicopters, and the 10-sec equivalent average energy level (LEQ(avg. 10-sec)) for chain saws. An owl-weighting (dBO) curve was estimated to emphasize the middle frequency range where strigiform owls have the highest hearing sensitivity. Manipulated and nonmanipulated nest sites did not differ in reproductive success (P = 0.59) or the number of young fledged (P = 0.12). As stimulus distance decreased, spotted owl flush frequency increased, regardless of stimulus type or season. We recorded no spotted owl flushes when noise stimuli were >105 m away. Spotted owls returned to predisturbance behavior within 10-15 min after a stimulus event. All adult flushes during the nesting season occurred after juveniles had left the nest. Spotted owl flush rates in response to helicopters did not differ between nonnesting (13.3%) and nesting seasons (13.6%; P = 0.34). Spotted owls did not flush when the SEL noise level for helicopters was less than or equal to 102 dBO (92 dBA) and the LEQ level for chain saws was less than or equal to 59 dBO (46 dBA). Chain saws were more disturbing to spotted owls than helicopter flights at comparable distances. Our data indicate a 105-m buffer zone for helicopter overflights on the LNF would minimize spotted owl flush response and any potential effects on nesting activity. C1 US Forest Serv, Rocky Mt Res Stn, Flagstaff, AZ 86001 USA. No Arizona Univ, Sch Forestry, Flagstaff, AZ 86001 USA. USA, Construct Engn Res Labs, Champaign, IL 61826 USA. 49th Civil Engineer Squadron Environm Flight, Holloman AFB, NM 88330 USA. RP Delaney, DK (reprint author), USA, Construct Engn Res Labs, POB 9005, Champaign, IL 61826 USA. RI Beier, Paul/K-9294-2013 OI Beier, Paul/0000-0002-4297-4343 NR 43 TC 64 Z9 70 U1 3 U2 37 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 USA SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD JAN PY 1999 VL 63 IS 1 BP 60 EP 76 DI 10.2307/3802487 PG 17 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA 159WY UT WOS:000078199400006 ER PT J AU Brown, DK Cina, SJ Thompson, WC Titus, J Smialek, JE AF Brown, DK Cina, SJ Thompson, WC Titus, J Smialek, JE TI Concentrations of cardiac troponin I in postmortem body fluids: A laboratory marker for sudden cardiac death? SO LABORATORY INVESTIGATION 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 LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0023-6837 J9 LAB INVEST JI Lab. Invest. PD JAN PY 1999 VL 79 IS 1 MA 187 BP 35A EP 35A PG 1 WC Medicine, Research & Experimental; Pathology SC Research & Experimental Medicine; Pathology GA 162YZ UT WOS:000078376600195 ER PT J AU Askew, AW Zahn, CM Hall, KL AF Askew, AW Zahn, CM Hall, KL TI The significance of hyperkeratosis (HK) parakeratosis (PK) on otherwise normal Papanicolaou smears. SO LABORATORY INVESTIGATION LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Brooke Army Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0023-6837 J9 LAB INVEST JI Lab. Invest. PD JAN PY 1999 VL 79 IS 1 MA 216 BP 40A EP 40A PG 1 WC Medicine, Research & Experimental; Pathology SC Research & Experimental Medicine; Pathology GA 162YZ UT WOS:000078376600224 ER PT J AU Gill, S Kendall, B AF Gill, S Kendall, B TI Use of desmin immunohistochemistry distinguishes between mesothelial cells and carcinoma in serous fluid cell block preparations. SO LABORATORY INVESTIGATION 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 LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0023-6837 J9 LAB INVEST JI Lab. Invest. PD JAN PY 1999 VL 79 IS 1 MA 241 BP 44A EP 44A PG 1 WC Medicine, Research & Experimental; Pathology SC Research & Experimental Medicine; Pathology GA 162YZ UT WOS:000078376600249 ER PT J AU Kronz, JD Silberman, MA Allsbrook, WC Bastasky, S Burks, RT Cina, SJ Mills, SE Ross, JS Skar, WA Tomaszewski, JE True, LD Ulbright, TM Weinstein, MW Yantiss, RK Young, RH Epstein, JI AF Kronz, JD Silberman, MA Allsbrook, WC Bastasky, S Burks, RT Cina, SJ Mills, SE Ross, JS Skar, WA Tomaszewski, JE True, LD Ulbright, TM Weinstein, MW Yantiss, RK Young, RH Epstein, JI TI Pathology residents using a web-based tutorial improve Gleason grading of prostate carcinoma in needle biopsies. SO LABORATORY INVESTIGATION LA English DT Meeting Abstract C1 Med Coll Georgia, Augusta, GA 30912 USA. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Med Coll Virginia, Richmond, VA 23298 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Univ Virginia, Charlottesville, VA 22903 USA. Albany Med Ctr, Albany, NY USA. Wayne State Univ, Detroit, MI 48202 USA. Univ Penn, Philadelphia, PA 19104 USA. Univ Washington, Seattle, WA 98195 USA. Indiana Univ, Bloomington, IN 47405 USA. Univ Kentucky, Lexington, KY 40506 USA. Johns Hopkins Hosp, Baltimore, MD 21287 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0023-6837 J9 LAB INVEST JI Lab. Invest. PD JAN PY 1999 VL 79 IS 1 MA 576 BP 100A EP 100A PG 1 WC Medicine, Research & Experimental; Pathology SC Research & Experimental Medicine; Pathology GA 162YZ UT WOS:000078376600584 ER PT J AU Pack, DJ Kang, HS AF Pack, DJ Kang, HS TI Free gait control for a quadruped walking robot SO LABORATORY ROBOTICS AND AUTOMATION LA English DT Article AB Two major approaches exist for devising gait control for a legged machine: (2) finding a sequence of leg and body movements of a robot on the basis of kinematic and possibly dynamic considerations assuming all foot placements are valid and (2) selecting leg and body movements first on the basis of feasibility of foot placements (because the underlying terrain might render impossible certain foot placements) and then accepting those that also satisfy kinematic and possibly dynamic constraints. Consider now the problem of a legged robot pursuing a quarry. With the first approach, the robot will be limited to operating over a relatively flat terrain; over such a terrain, it might be able to synthesize a sequence of precomputed straight-line and turning gaits in order to match as closely as possible to the trajectory of the quarry. If the terrain is uneven, however, the robot will have no recourse but to take the second approach, even though it is computationally more demanding. The work done so far in the second approach is limited either by the constraint that the overall direction of ambulation of the robot is known in advance or by the constraint that the foot placements are limited to the points of ct grid superimposed on the topographic map of the terrain. This article presents how a free gait can be generated for folio wing a quarry with out invoking su ch constrain ts. The robot attempts to adapt constantly its direction of ambulation so that at each instant the quarry is pursued by the shortest path (although there is no guarantee that the path actually traversed by the robot is globally optimal in any sense). The directions generated by this "shortest path pursuit" prune away large segments of the search space for the discovery of appropriate foot placements. Simulated and experimental results are presented to validate the proposed gait control method. (C) 1999 John Wiley & Sons, Inc. C1 USAF Acad, Dept Elect Engn, Colorado Springs, CO 80840 USA. Purdue Univ, Robot Vis Lab, W Lafayette, IN 47906 USA. RP Pack, DJ (reprint author), USAF Acad, Dept Elect Engn, Colorado Springs, CO 80840 USA. NR 14 TC 10 Z9 10 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0895-7533 J9 LAB ROBOTICS AUTOMAT JI Lab. Robot. Autom. PY 1999 VL 11 IS 2 BP 71 EP 81 PG 11 WC Automation & Control Systems; Chemistry, Analytical; Robotics SC Automation & Control Systems; Chemistry; Robotics GA 187ET UT WOS:000079774500002 ER PT S AU Pachter, R AF Pachter, R BE Exarhos, GJ Guenther, AH Kozlowski, MR Lewis, KL Soileau, MJ TI New materials design for laser hardening applications SO LASER-INDUCED DAMAGE IN OPTICAL MATERIALS: 1998 SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Meeting Abstract CT 30th Annual Boulder Damage Symposium on Optical Materials for High-Power Lasers CY SEP 28-OCT 01, 1998 CL NATL INST STAND & TECHNOL, BOULDER, CO SP Univ Cent Florida, Ctr Res & Educ Opt & Lasers, Lawrence Livermore Natl Lab, Sandia Natl Lab, Defence Evaluat & Res Agcy, USAF Res Lab/Phillips Res Site, Univ New Mexico, Ctr High Technol Mat, Natl Inst Stand & Technol, Pacific NW Natl Lab, SPIE HO NATL INST STAND & TECHNOL C1 USAF, Res Lab, Mat Directorate, MLPJ,AFRL, Wright Patterson AFB, OH 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 0-8194-3045-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3578 BP 428 EP 430 DI 10.1117/12.344429 PG 3 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN06A UT WOS:000080520000049 ER PT J AU Collins, CB Davanloo, F Iosif, MC Dussart, R Hicks, JM Karamian, SA Ur, CA Kirischuk, VI Carroll, JJ Roberts, HE McDaniel, P Crist, CE AF Collins, CB Davanloo, F Iosif, MC Dussart, R Hicks, JM Karamian, SA Ur, CA Kirischuk, VI Carroll, JJ Roberts, HE McDaniel, P Crist, CE TI Evidence for the forced gamma emission from the 31-year isomer of hafnium-178 SO LASER PHYSICS LA English DT Article AB A sample containing 0.63 x 10(15) nuclei of the 4 quasiparticle isomer of Hf-178 having a half life of 31 years and excitation energy of 2.45 MeV was irradiated with X-ray pulses derived from a commercial X-ray unit typically used in dental medicine, it was operated at 15 mA to produce Bremsstrahlung radiation with an endpoint energy of 90 keV, With a high purity Ge detector the number of gamma photons collected from transitions between the lower members of the ground state band was found to increase by about 2% above that emitted by spontaneous decay of the isomer, Such an enhancement is consistent with an integrated cross section of 2 x 10(-21) cm(2) keV, a value in agreement with results scaled from comparable measurements for Ta-180. However, this is believed to be the first observation of photon initiated gamma emission, with a substantial gain in energy. This result has considerable significance to the development of a gamma-ray laser. C1 Univ Texas Dallas, Ctr Quantum Elect, Richardson, TX 75080 USA. Joint Inst Nucl Res, Dubna 141980, Russia. HH Natl Inst Phys & Nucl Engn, Bucharest, Romania. Nucl Res Inst, Ctr Sci, Kiev, Ukraine. Youngstown State Univ, Dept Phys & Astron, Ctr Photon Induced Proc, Youngstown, OH 44555 USA. SRS Technol, Syst Technol Grp, Huntsville, AL USA. DEPA, AF Res Lab, Kirtland AFB, Albuquerque, NM USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Univ Texas Dallas, Ctr Quantum Elect, Richardson, TX 75080 USA. EM cbc@utdallas.edu NR 5 TC 28 Z9 30 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 1054-660X EI 1555-6611 J9 LASER PHYS JI Laser Phys. PD JAN-FEB PY 1999 VL 9 IS 1 BP 8 EP 11 PG 4 WC Optics; Physics, Applied SC Optics; Physics GA 171DX UT WOS:000078848200003 ER PT S AU Senft, DC Fox, MJ Hamilton, CM Richter, DA Higdon, NS Kelly, BT AF Senft, DC Fox, MJ Hamilton, CM Richter, DA Higdon, NS Kelly, BT BE Kamerman, GW Werner, C TI Performance characterization and ground testing of an airborne CO2 differential absorption lidar system (Phase II) SO LASER RADAR TECHNOLOGY AND APPLICATIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Radar Technology and Applications IV CY JUN 16, 1999 CL MUNICH, GERMANY SP Soc Photo Opt Instrumentat Engineers, European Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev, Wissenschaftl Gesell Lasertech e V DE lidar; airborne lidar; laser radar; CO2 DIAL; laser remote sensing AB The Air Force Research Laboratory (AFRL) Active Remote Sensing Branch has developed the Laser Airborne Remote Sensing (LARS) system for chemical detection using the differential absorption lidar (DIAL) technique. The system is based on a high-power CO2 laser which can use either the standard (CO2)-C-12-O-16 Or the (CO2)-C-13-O-16 carbon dioxide isotopes as the lasing medium, and has output energies of up to 5 J on the stronger laser transitions. The lidar system is mounted on a flight-qualified optical breadboard designed for installation into the AFRL Argus C-135E optical testbed aircraft. The Phase I ground tests were conducted at Kirtland AFB in 1997, prior ro the LAPS flight tests performed in September 1997 at Kirtland AFB and the Idaho National Engineering and Environmental Laboratory (INEEL). The Phase II ground tests were conducted in 1998 to determine the optimum performance of the LARS system, after the incorporation of modifications and improvements suggested by the flight test results. This paper will present some of the chemical detection and radiometric results obtained during the Phase II ground tests. C1 USAF, Res Lab, Directed Energy Directorate, AFRL,DEBF, Kirtland AFB, NM 87117 USA. RP Senft, DC (reprint author), USAF, Res Lab, Directed Energy Directorate, AFRL,DEBF, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 3 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 0-8194-3181-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3707 BP 165 EP 176 DI 10.1117/12.351341 PG 12 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN20D UT WOS:000081059300016 ER PT S AU Pierrottet, DF Washer, CS Senft, DC AF Pierrottet, DF Washer, CS Senft, DC BE Kamerman, GW Werner, C TI Coherent remote optical sensor system overview SO LASER RADAR TECHNOLOGY AND APPLICATIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Radar Technology and Applications IV CY JUN 16, 1999 CL MUNICH, GERMANY SP Soc Photo Opt Instrumentat Engineers, European Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev, Wissenschaftl Gesell Lasertech e V DE LIDAR; heterodyne; acousto-optics; local oscillator; DIAL AB A wavelength agile coherent LIDAR system is under development at the Air Force Research Laboratory (AFRL). Coherent lidar has the potential of longer - range sensitivity than conventional direct detection systems. AFRL is conducting risk reduction experiments to address issues involved with coherent LIDAR. issues include speckle noise inherent to heterodyne detection, robust signal analysis algorithm development, and integration of a wavelength agile laser as the local oscillator to the receiver. The transmitter laser, developed for the LARS program, is a high energy TE CO2 laser hardened for airborne operations. Performance of the wavelength agile local oscillator laser is presented, and preliminary data from risk reduction experiments. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Pierrottet, DF (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 3 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 0-8194-3181-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3707 BP 197 EP 202 DI 10.1117/12.351343 PG 6 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN20D UT WOS:000081059300019 ER PT S AU Monson, TC Grantham, JW Childress, SW Sackos, JT Nellums, RO Lebien, SM AF Monson, TC Grantham, JW Childress, SW Sackos, JT Nellums, RO Lebien, SM BE Kamerman, GW Werner, C TI Characterization of scannerless LADAR SO LASER RADAR TECHNOLOGY AND APPLICATIONS IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Radar Technology and Applications IV CY JUN 16, 1999 CL MUNICH, GERMANY SP Soc Photo Opt Instrumentat Engineers, European Opt Soc, Commiss European Communities, Directorate Gen Sci Res & Dev, Wissenschaftl Gesell Lasertech e V DE laser radar; LADAR; scannerless LADAR; flash LADAR; image intensifier; microchannel plate ID RADAR AB Scannerless laser radar (LADAR) is the next revolutionary step in laser radar technology. It has the potential to dramatically increase the image frame rate over raster-scanned systems while eliminating mechanical moving parts. The system presented here uses a negative lens to diverge the light from a pulsed laser to floodlight illuminate a target. Return light is collected by a commercial camera lens, an image intensifier tube applies a modulated gain, and a relay lens focuses the resulting image onto a commercial CCD camera. To produce range data, a minimum of three snapshots is required while modulating the gain of the image intensifier tube's microchannel plate (MCP) at a MHz rate. Since November 1997 the scannerless LADAR designed by Sandia National Laboratories has undergone extensive testing. It has been taken on numerous field tests and has imaged calibrated panels up to a distance of 1 km on an outdoor range. Images have been taken at ranges over a kilometer and can be taken at much longer ranges with modified range gate settings. Sample imagery and potential applications are presented here. The accuracy of range imagery produced by this scannerless LADAR has been evaluated and the range resolution was found to be approximately 15 cm. Its sensitivity was also quantified and found to be many factors better than raster-scanned direct detection LADAR systems. Additionally, the effect of the number of snapshots and the phase spacing between them on the quality of the range data has been evaluated. Overall, the impressive results produced by scannerless LADAR are ideal for autonomous munitions guidance and various other applications. C1 USAF, Res Lab, Munit Directorate, Adv Guidance Div, Eglin AFB, FL 32542 USA. RP Monson, TC (reprint author), USAF, Res Lab, Munit Directorate, Adv Guidance Div, Eglin AFB, FL 32542 USA. NR 4 TC 11 Z9 11 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 0-8194-3181-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3707 BP 409 EP 420 DI 10.1117/12.351362 PG 12 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN20D UT WOS:000081059300039 ER PT S AU Paxton, AH AF Paxton, AH BE Kudryashov, AV TI Grating surface-emitting diode laser with lenslike medium SO LASER RESONATORS II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser Resonators II CY JAN 27-29, 1999 CL SAN JOSE, CA SP SPIE ID DFB AB A concept for a grating surface emitting (GSE) semiconductor laser with a lenslike medium that causes divergence along the lateral direction is described. In principle, the output beam can be diffraction limited. A second-order grating is fabricated with straight teeth which are perpendicular to the directions of propagation of the beams along the laser axis. The constant radius of curvature of the mode results in the matching of the reflected beam with the laser mode. The output beam will exhibit mild astigmatism which can easily be corrected. The astigmatism is the same for the waves traveling in both directions. The divergence of the mode discourages the breakup of the counterpropagating beams into filaments. Surface emission decreases the optical intensity of the laser mode and can essentially eliminate the output power through the facets. This type of laser is a candidate for high power operation. C1 USAF, Res Lab, VSSE, Kirtland AFB, NM 87117 USA. RP Paxton, AH (reprint author), USAF, Res Lab, VSSE, Kirtland AFB, NM 87117 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3081-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3611 BP 220 EP 227 DI 10.1117/12.349252 PG 8 WC Optics; Physics, Applied SC Optics; Physics GA BN13W UT WOS:000080851100024 ER PT S AU Rockwell, BA Toth, CA Roach, WP Payne, DJ Hopkins, RA Kennedy, PK Stolarski, DJ Noojin, GD Thomas, RJ Cain, CP AF Rockwell, BA Toth, CA Roach, WP Payne, DJ Hopkins, RA Kennedy, PK Stolarski, DJ Noojin, GD Thomas, RJ Cain, CP BE Jacques, SL Muller, GJ Roggan, A Sliney, DH TI Retinal damage mechanisms and safety for ultrashort laser exposure SO LASER-TISSUE INTERACTION X: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction X - Photochemical, Photothermal, and Photomechanical CY JAN 24-27, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc DE eye; safety; laser; nonlinear optics; retinal damage; nanosecond; picosecond; femtosecond ID PRIMATE EYE; AQUEOUS-MEDIA; PULSES; THRESHOLD; LESIONS AB For the past several years the US Air Force has led a research effort to investigate the thresholds and mechanisms for retinal damage from ultrashort laser pulses [i.e. nanosecond (10(-9) sec) to femtosecond (10(-15) sec) pulse widths]. The goal was to expand the biological database into the ultrashort pulse regime and thus to allow establishment of maximum permissible exposure limits for these lasers. We review the progress made in determining trends in retinal damage by ultrashort laser pulses in the visible and near infrared, including variations in spot size and number of pulses. We also discuss the most likely damage mechanisms operative in this pulse width regime and discuss relevance to laser safety. C1 USAF, Res Lab, Human Effectiveness Directorate, Directed Energy Bioeffects Div,Opt Radiat Branch, Brooks AFB, TX 78235 USA. RP Rockwell, BA (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Directed Energy Bioeffects Div,Opt Radiat Branch, 8111 18th St, Brooks AFB, TX 78235 USA. RI toth, cynthia/F-5614-2011 NR 20 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 0-8194-3071-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3601 BP 4 EP 10 DI 10.1117/12.349987 PG 7 WC Engineering, Biomedical; Immunology; Medicine, Research & Experimental; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Immunology; Research & Experimental Medicine; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN29E UT WOS:000081436500001 ER PT S AU Payne, DJ Jest, TR Elliott, JJ Eilert, BG Lott, L Lott, K Noojin, GD Hopkins, RA Lin, CP Rockwell, BA AF Payne, DJ Jest, TR Elliott, JJ Eilert, BG Lott, L Lott, K Noojin, GD Hopkins, RA Lin, CP Rockwell, BA BE Jacques, SL Muller, GJ Roggan, A Sliney, DH TI Cavitation thresholds in the rabbit retina pigmented epithelium SO LASER-TISSUE INTERACTION X: PHOTOCHEMICAL, PHOTOTHERMAL, AND PHOTOMECHANICAL, PROCEEDINGS OF SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Laser-Tissue Interaction X - Photochemical, Photothermal, and Photomechanical CY JAN 24-27, 1999 CL SAN JOSE, CA SP SPIE, Int Biomed Opt Soc AB We performed measurements to examine retinal injury from laser pulses in the sub-nanosecond time regime. Both ex-vivo porcine and Dutch belted rabbit retinal pigment epithelium (RPE)* models were used in conjunction with time reserved imaging to observe cavitation bubble formation. Included in this study are 3 ps, 300 fs, and 100 fs pulses at a wavelength of 580 nm, as well as 70 ps and 5 ns pulses at 532 nm. Threshold values varied between 37 mJ/cm(2) and 50 mJ/cm(2) across the range of pulse widths. Following laser irradiation cell viability was checked using a fluorescent dye marker(calcein). Our current results are compared to an earlier investigation using the artificial retina model. 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 3 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 0-8194-3071-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3601 BP 27 EP 31 DI 10.1117/12.350019 PG 5 WC Engineering, Biomedical; Immunology; Medicine, Research & Experimental; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Immunology; Research & Experimental Medicine; Ophthalmology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA BN29E UT WOS:000081436500004 ER PT J AU Ricci, RM AF Ricci, RM TI Untitled - Reply SO LASERS IN SURGERY AND MEDICINE LA English DT Letter C1 USAF, 374th Med Operat Squadron, Yokota Air Base, Japan. RP Ricci, RM (reprint author), USAF, 374th Med Operat Squadron, Yokota Air Base, Japan. NR 0 TC 6 Z9 6 U1 0 U2 0 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0196-8092 J9 LASER SURG MED JI Lasers Surg. Med. PY 1999 VL 24 IS 1 BP 2 EP 2 DI 10.1002/(SICI)1096-9101(1999)24:1<2::AID-LSM2>3.0.CO;2-T PG 1 WC Dermatology; Surgery SC Dermatology; Surgery GA 165CW UT WOS:000078502600002 ER PT S AU Mather, PT Barnes, W Hood, PJ Bunning, TJ AF Mather, PT Barnes, W Hood, PJ Bunning, TJ BE Bunning, TJ Chen, SH Chien, LC Kajiyama, T Koide, N Lien, SCA TI Rheo-optics studies in the development of hybrid liquid crystalline based MWIR polarizers SO LIQUID CRYSTAL MATERIALS AND DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Liquid Crystal Materials and Devices, at the 1999 MRS Spring Meeting CY APR 05-07, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, Everlight Chem Ind Corp, European Off Aerosp Res & Dev AB We present here a rheo-optical study of the flow behavior of two cholesteric liquid crystals, one with a large pitch and one with a small pitch. The large pitch compound has been investigated as a possible fixed wavelength polarizer in the mid-wavelength infra-red region (3-5 micron). The investigation of these compounds is driven by their low melt viscosity and ability to vitrify order, and thus functionality, into films with a wide range of thickness. In our attempts to obtain consistent thin films with reproducible contrast ratios, we explored the defect textures of both compounds under a polarizing optical microscope. These materials were sheared at various strain rates and at various temperatures in an attempt to determine the best processing window for defect free films. The pitch lengths of the two materials investigated were 160 and 1330 nm. The flow behavior of the large pitch material resembles a pure nematic with defect refinement taking place under flow. The short pitch material exhibited the typical Grandjean oily streaks upon shearing followed by coarsening. Observations made during this rheological study were used to identify a processing technique for the large pitch materials. Upon application of a conventional buffed alignment layer, films with consistent quality were routinely made. The measured polarization contrast of >70:1 exceeds the values obtained from state-of-the art commercial polarizers in this wavelength regime. C1 Mat & Mfg Directorate, MLBP, AFRL, Wright Patterson AFB, OH 45433 USA. RP Mather, PT (reprint author), Mat & Mfg Directorate, MLBP, AFRL, Wright Patterson AFB, OH 45433 USA. NR 9 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 1-55899-466-1 J9 MATER RES SOC SYMP P PY 1999 VL 559 BP 51 EP 56 PG 6 WC Crystallography; Materials Science, Multidisciplinary SC Crystallography; Materials Science GA BN69C UT WOS:000082590700006 ER PT S AU Klosterman, AM Pogue, RT Schmitt, MG Natarajan, LV Tondiglia, VP Tomlin, D Sutherland, RL Bunning, TJ AF Klosterman, AM Pogue, RT Schmitt, MG Natarajan, LV Tondiglia, VP Tomlin, D Sutherland, RL Bunning, TJ BE Bunning, TJ Chen, SH Chien, LC Kajiyama, T Koide, N Lien, SCA TI Voltage creep in holographic PDLC gratings SO LIQUID CRYSTAL MATERIALS AND DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Liquid Crystal Materials and Devices, at the 1999 MRS Spring Meeting CY APR 05-07, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, Everlight Chem Ind Corp, European Off Aerosp Res & Dev AB In holographic Bragg gratings formed by anisotropic photopolymerization of free-radical monomers, an electric field is required to switch the grating between a diffracting and a transmitting state. The voltage necessary to turn the grating completely off is defined as the switching voltage. In this work, we report on the gradual increase of this switching voltage with time after initial fabrication. The switching field increases approximately 60% over a seven-day period for a pentaacrylate/E7 material system. Using dielectric measurements, it is observed that the resistance of the cell does not change over time while the capacitance decreases. FT-IR spectroscopy was also used to explore the continued post-polymerization after fabrication of the gratings. Increases in switching field were observed for samples fully illuminated with light as well as those kept in the dark. We speculate that the rise in the switching voltage is caused by post polymerization of residual reactive moieties located near the polymer/nematic droplet interface. An increase in the amount of interfacial area generated by post-polymerization yields more surface area for the LC molecules to bind; thus a larger field is needed to switch. C1 MLPJ, AFRL, SOCHE, Wright Patterson AFB, OH 45433 USA. RP Klosterman, AM (reprint author), MLPJ, AFRL, SOCHE, Wright Patterson AFB, OH 45433 USA. NR 10 TC 10 Z9 10 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-466-1 J9 MATER RES SOC SYMP P PY 1999 VL 559 BP 129 EP 134 PG 6 WC Crystallography; Materials Science, Multidisciplinary SC Crystallography; Materials Science GA BN69C UT WOS:000082590700015 ER PT S AU Lincoln, DM Douglas, EP AF Lincoln, DM Douglas, EP BE Bunning, TJ Chen, SH Chien, LC Kajiyama, T Koide, N Lien, SCA TI Effect of processing variables on the magnetic field orientation of liquid crystalline thermosets SO LIQUID CRYSTAL MATERIALS AND DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Liquid Crystal Materials and Devices, at the 1999 MRS Spring Meeting CY APR 05-07, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, Everlight Chem Ind Corp, European Off Aerosp Res & Dev ID EPOXIDE THERMOSETS AB We have investigated the effect of various processing variables on the magnetic field orientation of a liquid crystalline epoxy. By using a modified fractional factorial design, we created an empirical model which can be used to predict the degree of orientation as a function of these variables. The model predicts the correct qualitative trends, namely that orientation increases with increasing magnetic field strength, increases with increasing time in the field, and decreases with increasing B-staging. The model also reveals some surprising effects of B-staging on the degree of orientation. C1 USAF, Res Lab, Mat Directorate, MLBP, Wright Patterson AFB, OH 45433 USA. RP Lincoln, DM (reprint author), USAF, Res Lab, Mat Directorate, MLBP, 2941 P St,Suite 1, Wright Patterson AFB, OH 45433 USA. NR 16 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 1-55899-466-1 J9 MATER RES SOC SYMP P PY 1999 VL 559 BP 183 EP 188 PG 6 WC Crystallography; Materials Science, Multidisciplinary SC Crystallography; Materials Science GA BN69C UT WOS:000082590700024 ER PT S AU Restaino, SR AF Restaino, SR BE Shashidhar, R TI Liquid crystal technology for adaptive optics SO LIQUID CRYSTAL MATERIALS, DEVICES, AND APPLICATIONS VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Liquid Crystal Materials, Devices, and Applications VII CY JAN 28-29, 1999 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, Soc Photo Opt Instrumentat Engineers DE liquid crystals; adaptive optics; wavefront compensation AB The ability to attain the highest possible resolution with any optical imaging system depends on maintaining the quality of the wavefront entering and passing through the system. Wavefront degradation can arise from errors in optical design and manufacture, random aberrators like the Earth's atmosphere, and the structure supporting the imaging system (this last contributor is especially troublesome for space-based systems). In the last two decades technology has been developed and tested to remove, in real-time, the effect of aberrators. This technology is commonly known as Adaptive Optics (AO). However, AO is expensive and very complicated. In an effort to reduce complexity and costs, alternative technologies are under study at various institutions. In this paper I will present the status of our effort in using liquid crystal devices as corrective elements for AO applications. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Restaino, SR (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 11 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 0-8194-3106-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3635 BP 74 EP 78 DI 10.1117/12.343857 PG 5 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BM84V UT WOS:000079917500010 ER PT J AU Tan, LS Burkett, JL Simko, SR Alexander, MD AF Tan, LS Burkett, JL Simko, SR Alexander, MD TI New aromatic benzazole polymers, 3 - Synthesis of rigid-rod benzobisazole polymers with main-chain 2,2 '-bipyridine-5,5 '-diyl units SO MACROMOLECULAR RAPID COMMUNICATIONS LA English DT Article ID BENZOBISTHIAZOLE; BENZOBISOXAZOLE; DERIVATIVES AB Rigid-rod benzobisthiazole (Bipy-PBZT), benzobisoxazole (Bipy-PBO) and benzobisimidazole (Bipy-PyBI) polymers containing 2,2'-bipyridine-5,5'-diyl moieties were synthesized from 2,2'-bipyridine-5,5'-dicarbonyl dichloride and one of the following monomers: 2,5-diamino-1,4-benzenedithiol, 4,6-diamino-1,3-benzenediol, and 2,3,5,6-tetraaminopyridine. Bipy-PyBI is the first rigid-rod benzobisimidazole polymer without any solubilizing pendants that exhibits lyotropic behavior. These polymers displayed thin-film electrical conductivity of approximate to 10(-10)-10(-8) S/cm in pristine state; 10(-5)-10(-4) S/cm upon infiltration with AgNO3; 25-42 S/cm after Ag+ --> Ag-0 reduction by NaBH4. C1 USAF, Polymer Branch, Mat & Mfg Technol Directorate, Res Lab,MLBP, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP Tan, LS (reprint author), USAF, Polymer Branch, Mat & Mfg Technol Directorate, Res Lab,MLBP, 2941 P St,Suite 1, Wright Patterson AFB, OH 45433 USA. OI Tan, Loon-Seng/0000-0002-2134-9290 NR 40 TC 12 Z9 14 U1 0 U2 3 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 1022-1336 J9 MACROMOL RAPID COMM JI Macromol. Rapid Commun. PD JAN PY 1999 VL 20 IS 1 BP 16 EP 20 DI 10.1002/(SICI)1521-3927(19990101)20:1<16::AID-MARC16>3.0.CO;2-4 PG 5 WC Polymer Science SC Polymer Science GA 159VH UT WOS:000078195400004 ER PT J AU Porta, S Thompson, E Otton, R Bacher, H Heidinger, D Smolle, KH Supanz, S Mitterhammer, H AF Porta, S Thompson, E Otton, R Bacher, H Heidinger, D Smolle, KH Supanz, S Mitterhammer, H TI Magnesium; electrolytes and blood gases during acute alcohol uptake at wine festivals SO MAGNESIUM-BULLETIN LA German DT Article AB The influence of chronic alcoholism upon magnesium state has already been shown by Siegenthaler (1987) or McCollister as early as 1963. Much less is known about magnesium reaction to acute ethanol intoxication in man. since determination of magnesium status during in vivo investigations in man must confine itself to (ionized) serum magnesium values, their correct interpretation is important. Interpretation however strongly depends upon the fact, whether dietetic alterations or stress are causing the magnesium changes. In a field experiment we therefore did not only measure electrolyte changes correlative with changes in blood ethanol content (BEC), but also changes in blood gases, pH and lactate for differential diagnosis of serum magnesium levels in 62 female and male probands at a "Klocher Traminer" wine festival. Regardless of their actual BEC, the probands were asked to return 30 minutes after their first blood sampling and were encouraged to keep on consuming alcohol or not, just to their liking. Most important results: 1. Ethanol uptake up to 0.5 promille leads to a clear fall in blood pH along with a slight fall in pO(2), which points i.a. towards an increased oxygen release into tissues. 2. With increasing ethanol consumption, pH and BE values increase by way of backregulation, which would explain the existence of pseudonormal pH or BE values at higher degrees of intoxication. 3. Electrolyte loss in the higher promille range hits Mg selectively hard, it increases along the ratio Na: Ca: Mg geometrically 1:2:4. C1 Graz Univ, Inst Allgemeine & Expt Pathol, A-8010 Graz, Austria. Inst Angew Stressforsch, Bad Radkersburg, Austria. USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. RP Porta, S (reprint author), Graz Univ, Inst Allgemeine & Expt Pathol, A-8010 Graz, Austria. NR 11 TC 1 Z9 1 U1 0 U2 1 PU KARL F HAUG VERLAG, HUTHIG GMBH PI HEIDELBERG PA IM WEIHER 10, 69121 HEIDELBERG, GERMANY SN 0172-908X J9 MAGNESIUM-B JI Magnes.-Bull. PY 1999 VL 21 IS 1 BP 14 EP 20 PG 7 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 179ZC UT WOS:000079359400003 ER PT J AU Porta, S Temmel, W Gifford, T Rand, J Westmoreland, D Sima, A Pfannhauser, W Bacher, H AF Porta, S Temmel, W Gifford, T Rand, J Westmoreland, D Sima, A Pfannhauser, W Bacher, H TI Human field experiments about the interrelationship of magnesium, electrolyte and blood gas changes proportional to the intensity of accumulated workload - a diagnostic approach SO MAGNESIUM-BULLETIN LA English DT Article ID STRESS AB Of 26 young volunteers on national service 50 mu l of capillary brood were taken just after light gymnastics and a 3 minutes jogging. Bicycle ergometry up to 200 watts (post stress provocation test, Poria ct al. 1993) was superimposed immediately, followed by a second blood sampling for determination of electrolytes, blood gases and lactate. A group of 20 more volunteers who did not undergo immediate previous stress, but sleep depriving night exercises followed by a field combat maneuver some hours beforehand, underwent the same procedure. The most important results: Ionized Mg was low in the first group and much higher in the second group, a feat not due to diet but to previous stress. Linear correlation between the parameters were the more plentiful, the higher the intensity of accumulated stress has been. Moreover, characteristic stress related interparameter correlation pattern (ICP) evolved, whereby Mg played an important role. Consequently, we formed 3 new subgroups, regardless of the previous workload, only characterized by the fact of an increasing or decreasing or stable reaction of ionized Mg to the ergometric test. Average values, correlation numbers and ICPs pointed to the fact, that the increasing Mg group consisted mainly of subjects in a significant better bodily shape than in the decreasing group. C1 Graz Univ, Inst Allgemeine & Expt Pathol, A-8010 Graz, Austria. Inst Appl Stress Res, Bad Radkersburg, Austria. USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. Graz Tech Univ, Inst Food Chem, A-8010 Graz, Austria. RP Porta, S (reprint author), Graz Univ, Inst Allgemeine & Expt Pathol, A-8010 Graz, Austria. NR 6 TC 16 Z9 16 U1 0 U2 1 PU KARL F HAUG VERLAG, HUTHIG GMBH PI HEIDELBERG PA IM WEIHER 10, 69121 HEIDELBERG, GERMANY SN 0172-908X J9 MAGNESIUM-B JI Magnes.-Bull. PY 1999 VL 21 IS 3 BP 61 EP 69 PG 9 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 237BK UT WOS:000082633600001 ER PT J AU Porta, S Temmel, W Gifford, T Rand, J Westmoreland, D Porta, G AF Porta, S Temmel, W Gifford, T Rand, J Westmoreland, D Porta, G TI Typical behavior of Mg, electrolyte, blood gas, and blood glucose in physically and psychically stressed individuals SO MAGNESIUM-BULLETIN LA English DT Article ID MAGNESIUM AB Blood gases (AVL compact 3), Mg, Na, Ca (AVL 988-4) and blood glucose (glocoseoxidase method) was measured out of 21 officer trainees before and after a cycle-ergometric workload of up to 250 watts for 12 minutes. The data were compared with the same parameters taken from 13 subjects shortly before accomplishing a bungee jump, thus having been subjected to hours of anxious waiting. Most important results: With the exception of 2 subjects, the bungee jumpers were able to respiratorily compensate their significantly lowered BE values without significant pH changes, which the ergometric group was unable to do. Furthermore, the psychologically stressed jumpers exhibited a marked and significant increase in blood glucose and Na, risk factors for ischemic heart disease. Those were absent in the ergometric group. Linear interparameter correlation patterns within the groups showed, that linear correlations evolved preferably within those groups, which were unable to compensate. In this context, correlations with Mg and pO(2) and pCO(2) in the group with high glucose and Na seem to mark already limited metabolic turnover, probably related to pre-jumping anxiety stress of longer duration. C1 Graz Tech Univ, Inst Allgemeine & Expt Pathol, A-8010 Graz, Austria. Inst Appl Stress Res Bad, Radkersburg, Austria. USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. RP Porta, S (reprint author), Graz Tech Univ, Inst Allgemeine & Expt Pathol, A-8010 Graz, Austria. NR 8 TC 1 Z9 1 U1 0 U2 1 PU KARL F HAUG VERLAG, HUTHIG GMBH PI HEIDELBERG PA IM WEIHER 10, 69121 HEIDELBERG, GERMANY SN 0172-908X J9 MAGNESIUM-B JI Magnes.-Bull. PY 1999 VL 21 IS 4 BP 109 EP 113 PG 5 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 269KR UT WOS:000084476400004 ER PT J AU Gummadi, LNB Palazotto, AN AF Gummadi, LNB Palazotto, AN TI Progressive failure analysis of laminated beams and arches undergoing large rotations SO MECHANICS OF COMPOSITE MATERIALS AND STRUCTURES LA English DT Article ID FINITE-ELEMENT ANALYSIS; COMPOSITE PLATES; DAMAGE; SHEAR AB A geometrically nonlinear finite-element formulation based on the total Lagrangian approach is used to predict the onset of various failure modes in laminated composite beams and arches. Some of the failure modes considered include matrix cracking, fiber breakage, and delamination. Numerical examples of beam and arch geometries are analyzed statically to observe the characteristics of large displacements and large rotations considering these failure modes. Large strain effects on load displacement characteristics are studied. Load-carrying capabilities of the composite beam and arch structures, after the first ply failure, are discussed. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. EM apalazot@afit.af.mil NR 19 TC 2 Z9 2 U1 0 U2 2 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA SN 1075-9417 J9 MECH COMPOS MATER ST JI Mech. Compos. Mater. Struct. PD JAN-MAR PY 1999 VL 6 IS 1 BP 69 EP 93 DI 10.1080/107594199305665 PG 25 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Composites SC Materials Science GA 165AH UT WOS:000078495900005 ER PT B AU Kent, BM AF Kent, BM GP NCSL/NIST NCSL/NIST NCSL/NIST TI Improvements in static Radar Cross Section calibration artifacts and procedures SO METROLOGY - AT THE THRESHOLD OF THE CENTURY ARE WE READY? LA English DT Proceedings Paper CT 1999 Workshop and Symposium on Metrology - At the Threshold of the Century are we Ready CY JUL 11-15, 1999 CL CHARLOTTE, NC AB The accurate measurement of Radar Cross Section (RCS) requires precise calibration "artifacts" as well as carefully executed measurement procedures. The Air Force Research Laboratory (AFRL) reviewed several existing common RCS calibration artifact standards and practices, and identified a number of improvements. Employing a modified "dual calibration" check procedure pioneered by AFRL, this paper will demonstrate improved RCS calibration fidelity for a wide variety of static RCS calibration measurement applications. Our calibration results are verified through an industrial inter-laboratory (range) measurement program employing selected calibration artifact standards. C1 USAF, Res Lab, AFRL, SNS, Wright Patterson AFB, OH 45433 USA. RP Kent, BM (reprint author), USAF, Res Lab, AFRL, SNS, Bldg 254,2591 K St, Wright Patterson AFB, OH 45433 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU NATL CONFERENCE STANDARDS LAB PI BOULDER PA 1800 30TH STREET, SUITE 305B, BOULDER, CO 80301 USA PY 1999 BP 249 EP 265 PG 17 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BP60M UT WOS:000085623700032 ER PT B AU Kent, BM AF Kent, BM GP NCSL/NIST NCSL/NIST NCSL/NIST TI The application of ANSI Z-540 to department of defense Radar Cross Section measurement facilities SO METROLOGY - AT THE THRESHOLD OF THE CENTURY ARE WE READY? LA English DT Proceedings Paper CT 1999 Workshop and Symposium on Metrology - At the Threshold of the Century are we Ready CY JUL 11-15, 1999 CL CHARLOTTE, NC AB The accurate measurement of static or dynamic Radar Cross Section (RCS) requires precision measurement equipment, clearly written and executed test procedures, and trained personnel. Three Department of Defense (DoD) RCS measurement facilities are currently participating in a demonstration program which attempts to formally centralize range documentation into an intranet electronic "range book", organized along ANSI-STD-Z540-1994-1((1,2)) as customized for RCS measurements((3)). This paper will review the background and progress to date on this important quality assurance effort, and discuss the process of reviewing the range books for compliance with the ANSI-Z540 standard. C1 USAF, Res Lab, AFRL, SNS, Wright Patterson AFB, OH 45433 USA. RP Kent, BM (reprint author), USAF, Res Lab, AFRL, SNS, Bldg 254,2591 K St, Wright Patterson AFB, OH 45433 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU NATL CONFERENCE STANDARDS LAB PI BOULDER PA 1800 30TH STREET, SUITE 305B, BOULDER, CO 80301 USA PY 1999 BP 279 EP 287 PG 9 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BP60M UT WOS:000085623700034 ER PT B AU Kent, BM AF Kent, BM GP NCSL/NIST NCSL/NIST NCSL/NIST TI The Department of Defense Certification Demonstration Project - An updated overview SO METROLOGY - AT THE THRESHOLD OF THE CENTURY ARE WE READY? LA English DT Proceedings Paper CT 1999 Workshop and Symposium on Metrology - At the Threshold of the Century are we Ready CY JUL 11-15, 1999 CL CHARLOTTE, NC C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Kent, BM (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU NATL CONFERENCE STANDARDS LAB PI BOULDER PA 1800 30TH STREET, SUITE 305B, BOULDER, CO 80301 USA PY 1999 BP 389 EP 389 PG 1 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA BP60M UT WOS:000085623700049 ER PT J AU Lavine, BK Moores, AJ Mayfield, H Faruque, A AF Lavine, BK Moores, AJ Mayfield, H Faruque, A TI Genetic algorithms applied to pattern recognition analysis of high-speed gas chromatograms of aviation turbine fuels using an integrated Jet-A/JP-8 database SO MICROCHEMICAL JOURNAL LA English DT Article DE genetic algorithms; fuel spill identification; feature selection; pattern recognition; chromatographic fingerprinting ID IDENTIFICATION; GROUNDWATER; COMPONENTS AB High-speed gas chromatography was used to develop a potential method to type civilian and military jet fuels. A database of 212 gas chromatograms of neat jet fuel samples representing common aviation turbine fuels found in the United States (Jet-A, JP-5, JP-7, JP-8, and JPTS) was mined using a genetic algorithm, which was necessary because of the similarities of the gas chromatograms in the database. Principal-component models developed from gas chromatography peaks identified by the genetic algorithm were able to correctly classify the gas chromatograms of neat jet fuels, and these models were also able to successfully classify the gas chromatograms of jet fuels that had undergone weathering in a subsurface environment. The present study, which is a logical extension of an earlier effort was undertaken because of the change from JP-4 to JP-8 as the principal U.S. Air Force fuel. (C) 1999 Academic Press. C1 Clarkson Univ, Dept Chem, Potsdam, NY 13699 USA. Armstrong Lab, Environics Directorate, Tyndall AFB, FL 32403 USA. Mississippi Valley State Univ, Dept Comp Sci, Mississippi State, MS 38941 USA. RP Lavine, BK (reprint author), Clarkson Univ, Dept Chem, POB 5810, Potsdam, NY 13699 USA. NR 20 TC 19 Z9 19 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0026-265X J9 MICROCHEM J JI Microchem J. PD JAN PY 1999 VL 61 IS 1 BP 69 EP 78 DI 10.1006/mchj.1998.1673 PG 10 WC Chemistry, Analytical SC Chemistry GA 168RR UT WOS:000078706900009 ER PT J AU Edwards, AH Fowler, WB AF Edwards, AH Fowler, WB TI Recent advances in the theory of oxide-semiconductor interfaces SO MICROELECTRONICS RELIABILITY LA English DT Article ID ELECTRON-SPIN-RESONANCE; 111 SI/SIO2 INTERFACE; CORE-LEVEL SHIFTS; SI-SIO2 INTERFACE; SI(001)-SIO2 INTERFACE; PB CENTER; MICROSCOPIC STRUCTURE; CRYSTALLINE SIO2; SILICON; DEFECTS AB We present a review of recent results of atomic scale modeling of the silicon-oxide interface, including near-interface dielectric properties. The results are segregated into static properties, including such diverse cases as geometric conformation and XPS spectra of the interface and hyperfine interactions at point defects, and dynamic processes, including recent oxidation studies. In each case, we compare the theory with available experiment. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab Space Vehicles, Kirkland AFB, NM 87108 USA. Lehigh Univ, Dept Phys, Bethlehem, PA 18015 USA. Lehigh Univ, Sherman Fairchild Lab, Bethlehem, PA 18015 USA. RP Edwards, AH (reprint author), Univ N Carolina, Charlotte, NC 28223 USA. EM edwards@unc-c.edu RI Fowler, W/A-8821-2009 NR 61 TC 9 Z9 9 U1 0 U2 5 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 1999 VL 39 IS 1 BP 3 EP 14 DI 10.1016/S0026-2714(98)00205-4 PG 12 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 180LL UT WOS:000079387400001 ER PT S AU John, R DeLuca, D Nicholas, T Porter, J AF John, R DeLuca, D Nicholas, T Porter, J BE Miller, KJ McDowell, DL TI Near-threshold crack growth behavior of a single crystal Ni-base superalloy subjected to mixed-mode loading SO MIXED-MODE CRACK BEHAVIOR SE American Society for Testing and Materials Selected Technical Papers LA English DT Proceedings Paper CT Symposium on Mixed-Mode Crack Behavior CY MAY 06-07, 1998 CL ATLANTA, GA SP ASTM Comm E8 Fatigue & Fracture, ASTM Subcomm E08 01 Res & Educ DE fatigue crack growth; high temperature; microstructure; mixed mode; Mode I; and Mode II; single crystal; superalloy; threshold ID HIGH-CYCLE FATIGUE; DISK TEST; FRACTURE; STRESS AB Ni-base single crystal superalloys, which are used in applications such as gas: turbine engine blades, are primarily loaded along the [001] direction. Mode II (crystallographic shear) type cracking along the (111) plane is frequently the mode of growth in the early stages of fatigue failure of these components. Disks with a middle crack were used to characterize crystallographic shear crack growth from machined flaws oriented parallel to a (111) plane of a single crystal alloy. Automated crack growth experiments were conducted at constant stress ratio in the near threshold regime. Various combinations of Mode I and Mode II loading were achieved by orienting the machined flaw at different angles (theta) to the lending axis. Loading angle theta = 0 degrees (pure Mode I lending) resulted in crystallographic crack extension along alternating (111) slip systems producing a zig-zag pattern. This orientation exhibited significant resistance to self-similar crack growth from the machined flaw. In contrast, self-similar crack growth was achieved with relative ease for loading angles, theta not equal 0 degrees (mixed mode). In the mixed mode tests with K-1 > 0, the crack growth rate was 10 to 50 times higher than that under Mode I loading. Preliminary results indicate that crack growth is non-crystallographic at 593 degrees C. C1 USAF, Res Lab, Met Ceram & NDE Div, MLLN,Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Met Ceram & NDE Div, MLLN,Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 26 TC 8 Z9 8 U1 1 U2 2 PU AMER SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 0066-0558 BN 0-8031-2602-6 J9 AM SOC TEST MATER PY 1999 VL 1359 BP 312 EP 328 DI 10.1520/STP14256S PG 17 WC Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BN49W UT WOS:000082038200017 ER PT S AU Gustafson, SC Learn, AW AF Gustafson, SC Learn, AW BE Faust, NL Kessinger, S TI Evolutionary data visualization SO MODELING, SIMULATION, AND VISUALIZATION FOR REAL AND VIRTUAL ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Modeling, Simulation, and Visualization for Real and Virtual Environments CY APR 07-08, 1999 CL ORLANDO, FL SP SPIE AB Given data points that sample an unknown function in one independent variable, techniques are described and illustrated that generate additional data points "similar to" the given points. These techniques are optimal in two key respects. First, each technique models the data using a continuous family of functions, where each function is the smoothest possible in that energy is minimized. Here energy is a linear combination of lack-of-smoothness (defined as integrated squared second derivative of the function) and lack-of-fit (defined as sum squared deviation of the function from either the given points or the given points displaced to intersect their least squares line). Second, many members of the family compete in a robust evolutionary process to acquire energy, and the result of this competition determines the relative contribution of each member function. The techniques model the given points in that they yield probability density functions of the dependent variable for any value of the independent variable. Thus they enable the implementation of many pattern recognition and data visualization procedures. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Gustafson, SC (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 11 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 0-8194-3168-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3694 BP 83 EP 92 DI 10.1117/12.354467 PG 8 WC Computer Science, Software Engineering SC Computer Science GA BN68T UT WOS:000082586700010 ER PT S AU Stytz, MR Banks, SB Engel, M Garrett, C Harrison, G Kerr, G AF Stytz, MR Banks, SB Engel, M Garrett, C Harrison, G Kerr, G BE Faust, NL Kessinger, S TI Design and implementation of a space weather capability for a virtual space environment SO MODELING, SIMULATION, AND VISUALIZATION FOR REAL AND VIRTUAL ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Modeling, Simulation, and Visualization for Real and Virtual Environments CY APR 07-08, 1999 CL ORLANDO, FL SP SPIE DE distributed training; distributed virtual environments; virtual environments; space weather; ionospheric electron density; static charge build-up on spacecraft; parameterized atmospheric model AB An important modeling shortfall in current virtual environments developed for space applications is the absence of space weather conditions even though these conditions can drastically affect the conduct of space operations. One of the most prominent of these weather conditions is the distortion of the Earth's magnetosphere and the resulting change in electron density charge due to the solar wind. The absence of space weather in virtual environments will become more of an issue as the US Air Force and nations around the world increase their activities in space. To address a portion of this capability shortfall, our work extended the capabilities of the Virtual SpacePlane by modeling electron density levels in the near-Earth space environment and providing a visualization capability. Knowledge about the locations in the near-Earth space environment where the areas of critical electron density are located assists the spaceplane crewmember in planning missions that minimize the risk of electrical charge accumulation within the SpacePlane. Knowledge about the areas of high electron density is important because when space operations take place in low earth orbits, free electrons present in the space environment can collect on the surface of the space vehicle. The accumulation of free electrons can result in significant but uneven surface charging that can result in a potential difference, which can result in a static discharge. Electrical charge accumulation and discharge is a crew safety hazard since it often leads to electrical arcing and equipment damage. The severity of the damage depends upon the strength of the discharge and the spacecraft systems involved in the discharge event. Damage to the spacecraft can include spurious electronic switching activity, vehicle thermal material breakdown, amplifier and solar cell degradation, optical sensor degradation, and physical damage to the space vehicle's structure. The visualization capability we developed provides a rendering of the shell around the Earth that indicates where the electron density exceeds a critical value that could result in a dangerous static charge buildup. We used the Parameterized Ionospheric Model (PIM) model to calculate electron density. In this paper we briefly describe the VSP project, describe the requirements, goals and objectives of our project, and discuss the design and implementation of the space weather capability. We also describe the changes that we made to the user interface and VSP software architecture to accommodate the space weather capability. The paper concludes with a presentation of our results and suggestions for future work. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45431 USA. RP Stytz, MR (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45431 USA. NR 13 TC 0 Z9 0 U1 0 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3168-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3694 BP 108 EP 117 DI 10.1117/12.354469 PG 2 WC Computer Science, Software Engineering SC Computer Science GA BN68T UT WOS:000082586700012 ER PT S AU Stytz, MR Banks, SB AF Stytz, MR Banks, SB BE Faust, NL Kessinger, S TI Issues in development of an Air Force distributed mission training capability SO MODELING, SIMULATION, AND VISUALIZATION FOR REAL AND VIRTUAL ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Modeling, Simulation, and Visualization for Real and Virtual Environments CY APR 07-08, 1999 CL ORLANDO, FL SP SPIE DE distributed mission training; high level architecture; computer-generated actors; aircrew training; distributed virtual environments; fidelity; interoperability; design patterns; virtual environments ID VIRTUAL ENVIRONMENTS; SENSE AB Achieving a realistic, scaleable, effective distributed mission training (DMT) capability poses a variety of technical challenges in the areas of fidelity, visual systems, the High Level Architecture, computer-generated actors, reconfigurability, software architectures, and interoperability. While some aspects of these issues have received sufficient research attention to adequately support the initial deployment of distributed mission training systems, for most of the technical challenges much remains to be learned to attain the potential of large-scale DMT. In this paper, we discuss and illuminate the most pressing research issues that must be addressed to achieve the potential of DMT. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45431 USA. RP Stytz, MR (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45431 USA. NR 23 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 0-8194-3168-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3694 BP 204 EP 214 DI 10.1117/12.354480 PG 3 WC Computer Science, Software Engineering SC Computer Science GA BN68T UT WOS:000082586700022 ER PT J AU Song, HH Han, JY Tan, LS Dean, D AF Song, HH Han, JY Tan, LS Dean, D TI Thermotropic liquid crystalline behavior of dihydroxyphenylene benzobisthiazole derivatives SO MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS LA English DT Article; Proceedings Paper CT Korea-Japan Joint Forum 1998 (KJF 98) CY JUN 30-JUL 01, 1998 CL SAPPORO, JAPAN DE dihydroxyphenylene benzobisthiazole derivatives; tilted smectic phases; thermal behavior; optical texture; X-ray scattering ID RIGID-ROD POLYMERS AB Thermotropic liquid crystalline behaviors of dihydoxyphenylene benzobisthiazole with alkyl moieties of three different lengths at both ends were studied by d.s.c. polarizing optical microscope. and X-ray scattering. All three samples showed tilted smectic phases. Higher transition temperature and wider Sc interval were noted in DiOH-PBT-Cn. The alkoxy chain length lowered the transition temperature and temperature interval. C1 Hannam Univ, Dept Macromol Sci, Taejon 300791, South Korea. Wright Lab, MLBP, Polymer Branch, Mat Directorate, Wright Patterson AFB, OH 45469 USA. RP Song, HH (reprint author), Hannam Univ, Dept Macromol Sci, 133 Ojung Dong, Taejon 300791, South Korea. RI Tan, Loon-Seng/F-6985-2012 OI Tan, Loon-Seng/0000-0002-2134-9290 NR 3 TC 0 Z9 0 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 1058-725X J9 MOL CRYST LIQ CRYS A JI Mol. Cryst. Liq. Cryst. Sci. Technol. Sect. A-Mol. Cryst. Liq. Cryst. PY 1999 VL 327 BP 161 EP 164 DI 10.1080/10587259908026804 PG 4 WC Crystallography SC Crystallography GA 232RV UT WOS:000082384500039 ER PT B AU Farmer, BL Podojil, GM Pachter, R Adams, WW AF Farmer, BL Podojil, GM Pachter, R Adams, WW BE Morishima, Y Norisuye, T Tashiro, K TI Modeling of side-chain liquid crystal polysiloxanes SO MOLECULAR INTERACTIONS AND TIME-SPACE ORGANIZATION IN MACROMOLECULAR SYSTEMS LA English DT Proceedings Paper CT 3rd Osaka-University Macromolecular Symposium on Molecular Interactions and Time-Space Organization in Macromolecular Systems (OUMS 98) CY JUN 03-06, 1998 CL OSAKA UNIV, CTR CONVENT, OSAKA, JAPAN SP Osaka Univ, Ctr Convent, Org Macromol Syst, Osaka Univ, Int Exchange Program Macromol Sci, Minist Educ Sci Sports & Culture, Soc Polymer Sci HO OSAKA UNIV, CTR CONVENT ID FIELD AB Molecular dynamics (MD) simulations of polysiloxanes having cholesterol and methoxynitrostilbene (MONS) substituents tethered to the siloxane backbone by an allyloxybenzoate spacer group demonstrated that ordering involving all of the substituents developed quite rapidly, even though only the cholesterol group is by itself inherently mesogenic. The observed ordering varied with the nature and arrangement of the substituents. Generally, strong interactions between cholesterol groups resulted in the longest-lived pair-wise associations. MONS substituents also showed orientation, arising primarily from their associations with cholesterol mesogens. The overall order parameter was typically unaffected by the incorporation of MONS at fractions of the order of 25%. The polymer having alternating MONS and cholesterol substituents did not develop any significant order. Association Lifetimes were not simply related to order parameter. Polymers which achieved the highest order parameters did not exhibit the longest association lifetimes. Cholesterol - cholesterol associations tended to be the longest, MONS MONS associations the shortest. C1 USAF, Res Lab, MLBP, Wright Patterson AFB, OH 45433 USA. RP Farmer, BL (reprint author), USAF, Res Lab, MLBP, 2941 P St,Suite 1, Wright Patterson AFB, OH 45433 USA. NR 6 TC 0 Z9 0 U1 0 U2 2 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY BN 3-540-66110-7 PY 1999 BP 39 EP 44 PG 6 WC Polymer Science SC Polymer Science GA BP90E UT WOS:000086547000004 ER PT J AU Ohmer, MC Pandey, R AF Ohmer, MC Pandey, R TI Additional information on emergence of chalcopyrites as nonlinear optical materials - Reply SO MRS BULLETIN LA English DT Letter ID POLARIZED-LIGHT INTERFERENCE; ZNGEP2 BIREFRINGENCE C1 USAF, Res Lab, Washington, DC 20330 USA. Michigan Technol Univ, Houghton, MI 49931 USA. RP Ohmer, MC (reprint author), USAF, Res Lab, Washington, DC 20330 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD JAN PY 1999 VL 24 IS 1 BP 4 EP 5 PG 2 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 158AF UT WOS:000078093300003 ER PT J AU Callahan, M Harris, M Suscavage, M Bliss, D Bailey, J AF Callahan, M Harris, M Suscavage, M Bliss, D Bailey, J TI Synthesis and growth of gallium nitride by the chemical vapor reaction process (CVRP) SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article ID GAN; SUBSTRATE; SAPPHIRE AB A new process for synthesis and bulk crystal growth of GaN is described. GaN single crystal c-plane platelets up to 9mm by 2mm by 100 mu m thick have been grown by the Chemical Vapor Reaction Process (CVRP). The reaction between gallium and a nitrogen precursor is produced by sublimation of solid ammonium chloride in a carrier gas, which passes over gallium at a temperature of approximately 900 degrees C at near atmospheric pressures. Growth rates far the platelets were 25-100 mu m/hr in the hexagonal plane. Seeded growth in the c-direction was also accomplished by re-growth on previously grown c-plane platelets. The crystals were characterized by X-ray diffractometry, atomic force microscopy, secondary ion mass spectrometry, inert gas fusion, and room temperature Hall effect and resistivity measurements. C1 USAF, Res Lab, Sensors Directorate, Electromagnet Mat SNHX, Washington, DC 20330 USA. RP Callahan, M (reprint author), USAF, Res Lab, Sensors Directorate, Electromagnet Mat SNHX, Washington, DC 20330 USA. NR 21 TC 9 Z9 10 U1 5 U2 6 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 1999 VL 4 IS 10 BP art. no. EP 10 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 241ZU UT WOS:000082914400001 ER PT J AU Suscavage, M Harris, M Bliss, D Yip, P Wang, SQ Schwall, D Bouthillette, L Bailey, J Callahan, M Look, DC Reynolds, DC Jones, RL Litton, CW AF Suscavage, M Harris, M Bliss, D Yip, P Wang, SQ Schwall, D Bouthillette, L Bailey, J Callahan, M Look, DC Reynolds, DC Jones, RL Litton, CW TI High quality hydrothermal ZnO crystals SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article AB Zinc Oxide crystals have historically been grown in hydrothermal autoclaves with a basic mineralizer; however, doubts have been raised about the quality of such crystals because they have often exhibited large x-ray rocking curve widths and low photoluminescence (PL) yield with large linewidths. Several ZnO crystals were grown hydrothermally and sliced parallel to the c-plane. This resulted in opposite surfaces (the C+ and C-) exhibiting pronounced chemical and mechanical differences. Different surface treatments were investigated and compared by PL both at room temperature and liquid helium temperatures, and by double axis X-ray rocking curve measurements. The high quality of hydrothermally-grown ZnO is substantiated by the narrow rocking curve widths and sharp PL peaks obtained. A critical factor in obtaining these results was found to be surface preparation. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. Solid State Sci Corp, Hollis, NH 03049 USA. Wright State Univ, Univ Res Ctr, Dayton, OH 45435 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Suscavage, M (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 4 TC 31 Z9 33 U1 0 U2 3 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 1999 VL 4 SU 1 BP art. no. EP G3.40 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200043 ER PT J AU Zhu, LD Maruska, PH Norris, PE Yip, PW Bouthillette, LO AF Zhu, LD Maruska, PH Norris, PE Yip, PW Bouthillette, LO TI Epitaxial growth and structural characterization of single crystalline ZnGeN2 SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article AB A new nitride semiconductor, single crystalline ZnGeN2 has been successfully grown by MOCVD for the first time. The epitaxial ZnGeN2 is found to be of hexagonal wurtzite lattice without ordering of the zinc and germanium atoms in the pseudomorphic Group III sublattice. Lattice constants of the ZnGeN2 are a = 3.186 +/- 0.007 A, c = 5.174 +/- 0.012 A, which gives c/a = 1.624. C1 NZ Appl Technol, Woburn, MA 01801 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Zhu, LD (reprint author), NZ Appl Technol, 8A Gill St, Woburn, MA 01801 USA. NR 7 TC 8 Z9 8 U1 4 U2 9 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 1999 VL 4 SU 1 BP art. no. EP G3.8 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200020 ER PT J AU Wu, SL Webster, RT Anwar, AFM AF Wu, SL Webster, RT Anwar, AFM TI Physics-based intrinsic model for AlGaN/GaN HEMTs SO MRS INTERNET JOURNAL OF NITRIDE SEMICONDUCTOR RESEARCH LA English DT Article AB DC and intrinsic small signal parameters are reported for AlGaN/GaN high electron mobility transistors. The calculations are based upon a self-consistent solution of Schrodinger and Poisson's equation to model the quantum well formed in GaN. Transport parameters are obtained from an ensemble Monte Carlo simulation. C1 Univ Connecticut, Dept Elect & Syst Engn, Storrs, CT 06269 USA. USAF, Res Lab, Div Electromagnet Technol, Hanscom AFV, MA 01730 USA. RP Wu, SL (reprint author), Univ Connecticut, Dept Elect & Syst Engn, Storrs, CT 06269 USA. NR 8 TC 0 Z9 0 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 1999 VL 4 SU 1 AR G6.58 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 185QC UT WOS:000079680200123 ER PT S AU Rao, S AF Rao, S BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Atomistic simulations of cross-slip structures and processes in model FCC L1(0) TiAl SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID STACKING-FAULT ENERGY; EMBEDDED-ATOM METHOD; SCREW DISLOCATIONS; SINGLE-CRYSTALS; PURE COPPER; STRESS; METALS; ALLOYS; FLOW; ENERGETICS AB Three dimensional (3D) cross-slipped core structures of a/2[110] screw dislocations in model FCC structures are simulated using lattice statics within the Embedded Atom Method (EAM) formalism using potentials fitted to the elastic and structural properties of FCC Ni as well as L1(0) TiAl. 2 and 3-D Green's function (GF) techniques are used to relax the boundary forces in the simulations. The core structure of the constrictions are diffuse. At large separation distances between Shockley partials in the unconstricted configuration, the two constrictions formed by cross-slip onto a cross (111)plane have significantly different energy profiles suggesting that selfstress forces dominate the energetics of the cross-slip process. The variation in cross-slip energy with stacking-fault energy is in reasonable agreement with continuum predictions, excepting at high fault energy Values as in L1(0) TiAl. Cross-slip energies estimated for Cu, Ni and gamma-TiAl from these calculations show reasonable agreement with experimental data. The cross-slip energy shows a significantly weaker dependence on Escaig stress as compared to elasticity calculations, with the activation volume for the cross-slip process being approximately 20b(3) at an applied Escaig stress of 10(-3)mu in Cu. C1 USAF, Wright Lab, Mat Directorate, MLLM, Wright Patterson AFB, OH 45433 USA. RP Rao, S (reprint author), USAF, Wright Lab, Mat Directorate, MLLM, Wright Patterson AFB, OH 45433 USA. NR 46 TC 3 Z9 3 U1 1 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DRIVE, WARRENDALE, PA 15088-7563 USA SN 0272-9172 BN 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 77 EP 85 PG 9 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000008 ER PT S AU Wang, ZQ Lupo, J Patnaik, SS McKenney, A Pachter, R AF Wang, ZQ Lupo, J Patnaik, SS McKenney, A Pachter, R BE Bulatov, VV DiazdelaRubia, T Phillips, R Kaxiras, E Ghoniem, N TI Large scale molecular dynamics simulations of a liquid crystalline droplet with fast multipole implementations SO MULTISCALE MODELLING OF MATERIALS SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Multiscale Modelling of Materials, at the 1998 MRS Fall Meeting CY NOV 30-DEC 03, 1998 CL BOSTON, MA SP Mat Res Soc ID ALGORITHM AB The Fast Multipole Method (FMM) offers an efficient way (order O(N)) to handle long range electrostatic interactions, thus enabling more realistic molecular dynamics simulations of large molecular systems. The performance of the fast molecular dynamics (FMD) code, a parallel MD code being developed in our group, using the three-dimensional fast multipole method, shows a good speedup. The application to the full atomic-scale molecular dynamics simulation of a liquid crystalline droplet of 4-n-pentyl-4'-cyanobiphenyl (5CB) molecules, of size 35,872 atoms, shows strong surface effects on various orientational order parameters. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLPJ, Wright Patterson AFB, OH 45433 USA. RP Wang, ZQ (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLPJ, Wright Patterson AFB, OH 45433 USA. NR 7 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 1-55899-444-0 J9 MATER RES SOC SYMP P PY 1999 VL 538 BP 191 EP 196 PG 6 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA BN10W UT WOS:000080728000023 ER PT S AU Clark, N Furth, P AF Clark, N Furth, P BE Lindblad, T Padgett, ML Kinser, J TI Intelligent vision systems using dynamic neural networks SO NINTH WORKSHOP ON VIRTUAL INTELLIGENCE/DYNAMIC NEURAL NETWORKS: ACADEMIC/INDUSTRIAL/NASA/DEFENSE TECHNICAL INTERCHANGE AND TUTORIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 9th Workshop on Virtual Intelligence/Dynamic Neural Networks CY JUN 22-28, 1998 CL ROYAL INST TECHNOL, STOCKHOLM, SWEDEN SP NASA, SPIE - Int Soc Opt Engn, IEEE Ind Applicat Soc HO ROYAL INST TECHNOL ID SQUARES AB The design of a silicon eye using dynamical neural networks. Our silicon eye is capable of not only able to compensate for defocus, but it can also compensate for other aberrations including astigmatism, coma, and spherical aberrations, in addition, the silicon retina acts as a reconfigurable dynamic neural network to enable real-time image processing. The silicon eye uses three key enabling technologies. First, high-speed active pixel photo-diodes are uses as photo-detectors for both imaging and for wavefront sensing. The design of the active pixel photo-detectors is described along with experimental results characterizing their performance. Second, the analog signals received from the photo-detectors and processed by the active pixel circuitry is fed into a smart vision chip. The smart vision chip is a reconfigurable neural network capable of real-time reconstruction of the phase information associated with the imaging system. The micro mirrors are active optic devices that can be used to compensate for optical aberrations. Experimental results obtained from the circuit implementation of the dynamical neural networks are presented The experimental results obtained from our intelligent vision system demonstrate that dynamical neural networks offer advantages in speed, cost, size, and power consumption. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Clark, N (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 0-8194-3202-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3728 BP 130 EP 139 DI 10.1117/12.343031 PG 10 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Optics SC Engineering; Computer Science; Optics GA BM94V UT WOS:000080215800012 ER PT S AU Hassan, W Nagy, PB AF Hassan, W Nagy, PB BE Green, RE TI Grain noise in interferometric detection of ultrasonic vibrations: Experimental study SO NONDESTRUCTIVE CHARACTERIZATION OF MATERIALS IX SE AIP Conference Proceedings LA English DT Proceedings Paper CT 9th International Symposium on Nondestructive Characterization of Materials CY JUN 28-JUL 02, 1999 CL SYDNEY, AUSTRALIA SP Amer Soc Nondestruct Testing, NASA, Langley Res Ctr, Natl Sci Fdn, USN, Off Res, USA, Res Off Far E, USAF, Asian Off Aerosp R&D, USN, Off Res Int Field Off Asia ID MICROSCOPE AB Beside their other obvious advantages over conventional ultrasonic sensors, laser interferometers offer optical diffraction limited apertures that are far smaller than the acoustic wavelength in the specimen under inspection In this paper experimental results are presented for the incoherent material noise in 2024 aluminum and Ti-6Al-4V titanium alloys at two different nominal frequencies of 5 and 10 MHz. It is shown that the incoherent grain noise significantly increases as the illuminated spot size decreases. C1 USAF, Res Lab, Mat Mfg Directorate, Met Ceram & NDE Div, Wright Patterson AFB, OH 45433 USA. RP Hassan, W (reprint author), USAF, Res Lab, Mat Mfg Directorate, Met Ceram & NDE Div, Wright Patterson AFB, OH 45433 USA. RI Nagy, Peter/O-5404-2016 OI Nagy, Peter/0000-0001-5715-2409 NR 13 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 1-56396-911-4 J9 AIP CONF PROC PY 1999 VL 497 BP 180 EP 185 PG 6 WC Materials Science, Characterization & Testing; Physics, Applied SC Materials Science; Physics GA BP29Z UT WOS:000084618600027 ER PT S AU Ha, JC Smith, B Bush, J AF Ha, JC Smith, B Bush, J BE Kim, BY Hotate, K TI Fiber Optic Rate Gyro development SO OFS-13: 13TH INTERNATIONAL CONFERENCE ON OPTICAL FIBER SENSORS & WORKSHOP ON DEVICE AND SYSTEM TECHNOLOGY TOWARD FUTURE OPTICAL FIBER COMMUNICATION AND SENSING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 13th International Conference on Optical Fiber Sensors and Workshop on Device and System Technology Toward Future Optical Fiber Communication and Sensing CY APR 12-16, 1999 CL KYONGJU, SOUTH KOREA SP SPIE, Opt Soc Korea, IEICE Electr Soc, Japan, Inst Electr Engineers Korea, Korea Inst Commun Sci, Korea Inst Elect Engineers, Korean Sensors Soc, Japan Soc Appl Phys, Inst Elect Engineers Japan, Soc Instrument & Control Engineers, Japan, Opt Soc Amer, IEEE Lasers & Electro Opt Soc AB The Fiber Optic Rate Gyro can be configured as a form-fit-function replacement for targeted systems. Key advantages include a lightweight solid state configuration with extended operating life and immunity from most forms of electromagnetic interference. C1 USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Ha, JC (reprint author), USAF, Res Lab, Sensors Directorate, 2241 Avion Circle, 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 0-8194-3228-8 J9 P SOC PHOTO-OPT INS PY 1999 VL 3746 BP 276 EP 279 PG 4 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics; Telecommunications SC Engineering; Instruments & Instrumentation; Optics; Telecommunications GA BN81U UT WOS:000083083000061 ER PT B AU Lillie, TH AF Lillie, TH BE Harmon, D TI Balancing operational and environmental requirements for military ranges and airspace SO ON THE FRONTIERS OF CONSERVATION: PROCEEDINGS OF THE TENTH CONFERENCE ON RESEARCH AND RESOURCE MANAGEMENT IN PARKS AND ON PUBLIC LANDS LA English DT Proceedings Paper CT 10th Conference on Research and Resource Management in Parks and on Public Lands/George-Wright-Society Biennial Conference CY MAR 22-26, 1999 CL ASHEVILLE, NC SP George Wright Soc, US Natl Pk Serv, US Geol Survey, Biol Resources Div C1 USAF, Mil Liaison Dept Interior, Washington, DC 20240 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU GEORGE WRIGHT SOCIETY, INC. PI HANCOCK PA PO BOX 65, HANCOCK, MI 49930-0065 USA PY 1999 BP 364 EP 366 PG 3 WC Environmental Studies; Public Administration SC Environmental Sciences & Ecology; Public Administration GA BP35H UT WOS:000084811100064 ER PT S AU Fernelius, NC Hopkins, FK Ohmer, MC AF Fernelius, NC Hopkins, FK Ohmer, MC BE Lal, RB Frazier, DO TI Nonlinear optical crystal development for laser wavelength shifting at AFRL Materials Directorate SO OPERATIONAL CHARACTERISTICS AND CRYSTAL GROWTH OF NONLINEAR OPTICAL MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Operational Characteristics and Crystal Growth of Nonlinear Optical Materials CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE non-linear optics; optical parametric oscillator; second harmonic generation; chalcopyrites; borates ID MATCHED 2ND-HARMONIC GENERATION; BONDED-STACKED GAAS; ALGAAS WAVE-GUIDES; FREQUENCY-CONVERSION; GROWTH; AGGASE2; CDGEAS2; BORATE; ZNGEP2 AB Our objective is to develop crystals that shift the light from well developed laser sources to application specific wavelengths which may be tunable. Military applications extend across the entire spectrum from ultraviolet through the far-infrared but our greatest interest has been in materials for the mid-IR (3-5 mu m) and far-IR (8-12 mu m) atmospheric windows. Our primary applications that drive crystal development are infrared countermeasures and remote sensing of chemical and biological warfare agents. To achieve these results we have pursued two tracks: birefringent bulk materials and quasi-phase-matched structures. Birefringent studies include the grey track problem in KTiOPO4 (KTP) plus growth of its isomorphs, KTiOAsO4 (KTA), RbTiOAsO4(RTA), CsTiOAsO4(CTA) and KxRbl-xTiOPO4 (KRTA); chalcopyrites: ZnGeP2, CdGeAs2, AgGaS2, AgGaSe2, AgGa(1-x)InxSe2, AgGaTe2; plus GaSe, and HgGa2S4. A small portion of the effort is pursuing UV materials, the foremost being the berates MM'(B3O5)(3) where M = Sr, Ba, Pb; M'= Li,Na. Previously, work was done on LiB3O5 (LBO), beta-BaB2O4 (BBO) and CsLiB6O10 (CLBO). Quasi-phase-matched (QPM) techniques include inverted segments by diffusion bonding (GaAs), by periodic poling (LiNbO3, LiTaO3, KTP, BaTiO3) and by periodic doping. To cover the 4.5-5.0 mu m band, work is being done on RTA and Pb{MgxNbyTi1-x-y}O-3 (PMNT). For periodic poling in the 8-12 mu m region studies are being made on CGC (CsGeCl3), CGB (CsGeBr3), Tl3PbBr5, Tl(4)Pbl(6) and Tl4HgI6. QPM can also be obtained using total internal reflection devices (GaAs, ZnSe). 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 42 TC 13 Z9 13 U1 1 U2 7 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3279-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3793 BP 2 EP 8 DI 10.1117/12.351399 PG 7 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN65Z UT WOS:000082519600001 ER PT S AU Guha, S Bartsch, M Hopkins, FK Eaton, MP Setzler, SD Schunemann, PG Pollak, TM AF Guha, S Bartsch, M Hopkins, FK Eaton, MP Setzler, SD Schunemann, PG Pollak, TM BE Lal, RB Frazier, DO TI Nonlinear absorption and laser damage threshold measurements of doped ZnGeP2 SO OPERATIONAL CHARACTERISTICS AND CRYSTAL GROWTH OF NONLINEAR OPTICAL MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Operational Characteristics and Crystal Growth of Nonlinear Optical Materials CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE ZnGeP2; nonlinear optical crystal; laser damage; nonlinear absorption AB Zinc germanium diphosphide (ZnGeP2) has proven to be an important nonlinear optical crystal for the generation of mid-wave infrared radiation, especially in an optical parametric oscillator configuration pumped by a Ho:YAG laser operating at 2.09 micrometers. Future applications will require higher intensity levels of the laser pump beam which are limited by the crystal's laser damage threshold and nonlinear absorption. These two quantities were measured for silver-doped ZnGeP2 samples of which one was uncoated, two had conventional anti-reflection coatings, and one had an AR coating with a quintic refractive index profile. Prominent nonlinear absorption was observed in some of the crystals; the nonlinear absorption coefficient was found to be anisotropic and a weak correlation between the values of the linear and the nonlinear absorption coefficient was observed. The values of the nonlinear optical coefficients measured in these crystals for ordinary and extraordinary polarizations of incident light are reported along with the measured values of the laser damage threshold of these newly grown crystals at 2.09 micrometers, both in the AR coated and uncoated forms. C1 USAF, Res Lab, Mat & Mfg Directorate, MLP, Wright Patterson AFB, OH 45433 USA. RP Guha, S (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLP, Wright Patterson AFB, OH 45433 USA. NR 8 TC 2 Z9 2 U1 1 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3279-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3793 BP 9 EP 12 DI 10.1117/12.351408 PG 4 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN65Z UT WOS:000082519600002 ER PT S AU Schepler, KL Missey, MJ O'Brien, N Powers, P AF Schepler, KL Missey, MJ O'Brien, N Powers, P BE Lal, RB Frazier, DO TI Power and energy scaling for quasi-phasematched OPOs SO OPERATIONAL CHARACTERISTICS AND CRYSTAL GROWTH OF NONLINEAR OPTICAL MATERIALS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Operational Characteristics and Crystal Growth of Nonlinear Optical Materials CY JUL 19-20, 1999 CL DENVER, CO SP SPIE DE optical parametric oscillator; periodically poled lithium niobate; quasi-phase-matching; infrared; laser ID OPTICAL PARAMETRIC OSCILLATOR; PERIODICALLY POLED LINBO3; LITHIUM-NIOBATE C1 USAF, Res Lab, AFRL, SNJT, Wright Patterson AFB, OH 45433 USA. RP Schepler, KL (reprint author), USAF, Res Lab, AFRL, SNJT, 3109 P St, Wright Patterson AFB, OH 45433 USA. OI Schepler, Kenneth/0000-0001-9658-2305 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 0-8194-3279-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3793 BP 187 EP 195 DI 10.1117/12.351414 PG 9 WC Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Materials Science, Coatings & Films; Optics SC Materials Science; Optics GA BN65Z UT WOS:000082519600023 ER PT J AU Leonard, DL Charlton, DG Hilton, TJ AF Leonard, DL Charlton, DG Hilton, TJ TI Effect of curing-tip diameter on the accuracy of dental radiometers SO OPERATIVE DENTISTRY LA English DT Article ID LIGHT-ACTIVATED COMPOSITES; UNITS; POLYMERIZATION; CURE; INTENSITY; OUTPUT; DEPTH AB The purpose of this study was to determine the accuracy of four commercially available radiometers when curing tips of different diameters were used. A visible-light curing unit (Optilux 500) with a new 80-watt quartz-halogen bulb (OptiBulb) was used as the light source for all measurements. The unit's irradiance value was measured using three hand-held radiometers (Demetron model #100, Cure-Rite model #644726, and Coltolux Light Meter) and a built-in visible-light curing unit radiometer (Optilux 500). Measurements were made with four curing tips of diameters 4 mm, 7.5 mm, 10.5 mm, and 12 mm. For each tip, trials were made with five radiometers of each model. Student's t-tests at the 0.05 level of significance were used to compare the mean irradiance measured by each model of radiometer to the irradiance value measured by a laboratory-grade power meter. A one-way analysis of variance at the 0.05 level of significance was used to compare the irradiance values among the five samples of each commercially available radiometer model. Except for the Optilux 500 built-in radiometer with the 10.5-mm tip, all the commercially available radiometers exhibited irradiance values significantly different from those of the laboratory-grade power meter. There were no statistically significant differences among the five samples of each commercially available radiometer model. C1 USAF, Dent Invest Serv, Brooks AFB, TX 78235 USA. RP Leonard, DL (reprint author), USAF, Dent Invest Serv, Brooks AFB, TX 78235 USA. NR 26 TC 33 Z9 33 U1 0 U2 1 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 1999 VL 24 IS 1 BP 31 EP 37 PG 7 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 152NQ UT WOS:000077784000007 PM 10337296 ER PT J AU Palmer, AE Davis, RD Murchison, DF Cohen, RB AF Palmer, AE Davis, RD Murchison, DF Cohen, RB TI Fracture strength of class 2 amalgams with various cavity-lining materials SO OPERATIVE DENTISTRY LA English DT Article ID PHYSICAL-PROPERTIES; CEMENT; BASE AB This in vitro study compared the fracture resistance of class 2 amalgam restorations placed over seven materials: three resin-modified glass-ionomer cements (Fuji II LC, Vitrebond, and Vitremer), one polyacid-modified composite resin (VariGlass VLC), two conventional glass-ionomer cements (Ketac-Bond and GlasIonomer Cement), and one calcium-hydroxide material (Dycal). Eighty maxillary molars with flattened occlusal surfaces were divided into 14 experimental groups and two control (no liner) groups. One standardized class 2 amalgam cavity preparation was completed per tooth. Lining materials standardized at a thickness of 0.5 mm were placed in the approximal box portion of 10 test specimens per experimental group. Spherical amalgam was hand condensed into each cavity preparation. At 1 hour and again at 7 days, five samples from each group were fractured in compression using an Instron Universal Testing Machine. The force was directed at 10 degrees to the long axis of the tooth, 2.0 mm inside the approximal portion of the restoration. Results were analyzed using a two-way ANOVA for time and material. No statistically significant differences were found among the materials and controls at either time interval tested (P > 0.05). A statistically significant difference was found (P < 0.05) when comparing 1-hour and 7-day strengths. The 7-day specimens were more resistant to fracture than the 1-hour specimens. Conclusion: the fracture resistance of amalgam restorations was not affected by the presence of a material 0.5 mm thick placed in the approximal box when 3 mm of bulk of amalgam remained over it. C1 81st Dent Squadron SGD, Keesler AFB, MS 39534 USA. RP Palmer, AE (reprint author), USAF, FE Warren AFB, WY 82005 USA. NR 13 TC 3 Z9 3 U1 0 U2 1 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 1999 VL 24 IS 1 BP 45 EP 50 PG 6 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 152NQ UT WOS:000077784000009 PM 10337298 ER PT S AU Gord, JR Tyler, C Grinstead, KD Fiechtner, GJ Cochran, MJ Frus, JR AF Gord, JR Tyler, C Grinstead, KD Fiechtner, GJ Cochran, MJ Frus, JR BE Cha, SS BryanstonCross, PJ Mercer, CR TI Imaging strategies for the study of gas turbine spark ignition SO OPTICAL DIAGNOSTICS FOR FLUIDS/HEAT/COMBUSTION AND PHOTOMECHANICS FOR SOLIDS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Diagnostics for Fluids Heat Combustion and Photomechanics for Solids CY JUL 21-23, 1999 CL DENVER, CO SP SPIE DE visualization; imaging; ultrafast lasers; CCD cameras; vortex-flame interactions; spark ignition AB Spark-ignition systems play a critical role in the performance of essentially all gas turbine engines. These devices are responsible for initiating the combustion process that sustains engine operation. Demanding applications such as cold start and high-altitude relight require continued enhancement of ignition systems. To characterize advanced ignition systems, we have developed a number of laser-based diagnostic techniques configured for ultrafast imaging of spark parameters including emission, density, temperature, and species concentration. These diagnostics have been designed to exploit an ultrafast-framing charge-coupled-device (CCD) camera and high-repetition-rate laser sources including modelocked Ti:sapphire oscillators and regenerative amplifiers. Spontaneous-emission and laser-schlieren measurements have been accomplished with this instrumentation and the results applied to the study of a novel Unison Industries spark igniter that shows great promise for improved cold-start and high-altitude-relight capability as compared to that of igniters currently in use throughout military and commercial fleets. Phase-locked and ultrafast real-time imaging strategies are explored, and details of the imaging instrumentation, particularly the CCD camera and laser sources, are discussed. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Gord, JR (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 14 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 0-8194-3269-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3783 BP 352 EP 361 DI 10.1117/12.365756 PG 10 WC Instruments & Instrumentation; Mechanics; Materials Science, Characterization & Testing; Optics SC Instruments & Instrumentation; Mechanics; Materials Science; Optics GA BN97Z UT WOS:000083741900039 ER PT J AU Horner, JL Javidi, B AF Horner, JL Javidi, B TI Optical security SO OPTICAL ENGINEERING LA English DT Editorial Material C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. Univ Connecticut, Dept Elect Engn, Storrs, CT 06269 USA. RP Horner, JL (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 0 TC 17 Z9 17 U1 0 U2 0 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, BELLINGHAM, WA 98225 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD JAN PY 1999 VL 38 IS 1 BP 8 EP 8 DI 10.1117/1.602039 PG 1 WC Optics SC Optics GA 157XY UT WOS:000078088000002 ER PT S AU Nichter, JE AF Nichter, JE BE Beiser, L Sagan, SF Marshall, GF TI Photonic implementation of Phased Array Antennas (RF scanning) SO OPTICAL SCANNING: DESIGN AND APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optical Scanning - Design and Application CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE photonics; fiber optics; squint; True Time Delay; wavelength division multiplexing (WDM); optical Rotman lens; Butler matrix AB Phased Array Antennas (PAA) provided angular scanning (beam steering) from fixed antenna structures. Photonics can accomplish the beam steering with improvements in size and weight along with the remoting benefits utilizing fiber optics. Photonic advantages include True Time Delay (TTD) beam steering eliminating the beam squint imposed by phase shifted signals produced in an electronic implementation. Another benefit of beam steering is the ability to position nulls in the spacial pattern to reduce the interference signals. Hybrid circuits utilizing both photonic and electronic components take advantages of the best aspects of each technology. Various types of photonic implementations are included. C1 USAF, Res Lab, SNDR, Rome, NY 13441 USA. RP Nichter, JE (reprint author), USAF, Res Lab, SNDR, Rome, NY 13441 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3273-3 J9 P SOC PHOTO-OPT INS PY 1999 VL 3787 BP 128 EP 137 DI 10.1117/12.351637 PG 10 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BN65X UT WOS:000082518800013 ER PT J AU Kovanis, V Erneux, T Gavrielides, A AF Kovanis, V Erneux, T Gavrielides, A TI Largely detuned injection-locked semiconductor lasers SO OPTICS COMMUNICATIONS LA English DT Article ID OPTICAL-INJECTION; LOCKING; SUBJECT; STABILITY; BANDWIDTH; DYNAMICS AB The equations for a semiconductor laser subject to injection are examined numerically and analytically for large values of the detuning parameter. Our analysis is motivated by recent experimental studies using either distributed feedback laser diodes or vertical-cavity surface-emitting lasers. For negative detuning, we show that a pulsating intensity regime may coexist with a stable steady state. Transitions between time-periodic and steady states as the injection rate is progressively increased or decreased appear through sudden jumps. Of particular interest is the fact that the upper locking point corresponds to a bifurcation point to quasiperiodic intensity oscillations. For positive detuning, the pulsating intensity regime is the only stable state until steady state locking smoothly occurs through a Hopf bifurcation point. Our analysis is based on a new asymptotic analysis of the semiconductor laser equations which allows analytical expressions for all bifurcation points. (C) 1999 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. RP Kovanis, V (reprint author), USAF, Res Lab, Nonlinear Opt Grp, 3350 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 15 TC 24 Z9 24 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD JAN 1 PY 1999 VL 159 IS 1-3 BP 177 EP 183 DI 10.1016/S0030-4018(98)00584-7 PG 7 WC Optics SC Optics GA 155DB UT WOS:000077929800027 ER PT S AU Anderson, GP Berk, A Acharya, PK Matthew, MW Bernstein, LS Chetwynd, JH Dothe, H Adler-Golden, SM Ratkowski, AJ Felde, GW Gardner, JA Hoke, ML Richtsmeier, SC Pukall, B Mello, J Jeong, LS AF Anderson, GP Berk, A Acharya, PK Matthew, MW Bernstein, LS Chetwynd, JH Dothe, H Adler-Golden, SM Ratkowski, AJ Felde, GW Gardner, JA Hoke, ML Richtsmeier, SC Pukall, B Mello, J Jeong, LS BE Kohnle, A Gonglewski, JD TI MODTRAN4: Radiative transfer modeling for remote sensing SO OPTICS IN ATMOSPHERIC PROPAGATION AND ADAPTIVE SYSTEMS III 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 III CY SEP 23-24, 1999 CL FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy DE MODTRAN; remote sensing; surface albedos; aerosols; multiple scattering ID MULTIPLE-SCATTERING; ATMOSPHERIC FLUXES; COOLING RATES; WATER-VAPOR; CLOUD; ALGORITHM; SURFACES; MODIS AB MODTRAN4, the newly released version of the U.S. Air Force atmospheric transmission, radiance and flux model is being developed jointly by the Air Force Research Laboratory / Space Vehicles Directorate (AFRL / VS) and Spectral Sciences, Inc. It is expected to provide the accuracy required for analyzing spectral data for both atmospheric and surface characterization. These two quantities are the subject of satellite and aircraft campaigns currently being developed and pursued by, for instance: NASA (Earth Observing System), NPOESS (National Polar Orbiting Environmental Satellite System), and the European Space Agency (GOME - Global Ozone Monitoring Experiment). Accuracy improvements in MODTRAN relate primarily to two major developments: (I) the multiple scattering algorithms have been made compatible with the spectroscopy by adopting a correlated-k approach to describe the statistically expected transmittance properties for each spectral bin and atmospheric layer, and (2) radiative transfer calculations can be conducted with a Beer-Lambert formulation that improves the treatment of path inhomogeneities. Other code enhancements include the incorporation of solar azimuth dependence in the DISORT-based multiple scattering model, the introduction of surface BRDF (Bidirectional Radiance Distribution Functions) models and a 15 cm(-1) band model for improved computational speed. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Anderson, GP (reprint author), USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. NR 24 TC 29 Z9 30 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 0-8194-3461-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3866 BP 2 EP 10 DI 10.1117/12.371318 PG 9 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BP46D UT WOS:000085206200001 ER PT S AU Ratkowski, AJ Anderson, GP Devir, AD AF Ratkowski, AJ Anderson, GP Devir, AD BE Kohnle, A Gonglewski, JD TI Comparison of atmospheric transmittance measurements in the 3-5 and 8-12 micron spectral regions with MODTRAN: considerations for long, near-horizontal, path geometries SO OPTICS IN ATMOSPHERIC PROPAGATION AND ADAPTIVE SYSTEMS III 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 III CY SEP 23-24, 1999 CL FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy DE infrared; atmospheric transmittance; long slant path; MODTRAN; sensitivity analysis AB Radiance measurements conducted from a high-altitude platform to retrieve surface properties will potentially 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. This paper compares experimental measurements in geometries of interest with calculations using the latest version of MODTRAN. Results indicate a strong dependence of the remotely sensed radiation on both the aerosol and water vapor content. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Ratkowski, AJ (reprint author), USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. NR 3 TC 2 Z9 2 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 0-8194-3461-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3866 BP 11 EP 22 DI 10.1117/12.371324 PG 12 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BP46D UT WOS:000085206200002 ER PT S AU Matson, CL Liu, HL Landesman, BT Christopher, R AF Matson, CL Liu, HL Landesman, BT Christopher, R BE Kohnle, A Gonglewski, JD TI Imaging and localization in turbid media SO OPTICS IN ATMOSPHERIC PROPAGATION AND ADAPTIVE SYSTEMS III 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 III CY SEP 23-24, 1999 CL FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy DE backpropagation; turbid media; optical diffusion tomography; diffraction tomography ID TISSUE AB We apply our previously-developed turbid-media backpropagation algorithm to imaging extended objects imbedded in turbid media such as clouds. Although the backpropagation algorithm was developed initially for biomedical applications, the underlying development is general enough to encompass imaging objects imbedded in any sort of turbid media whose scattering properties dominate their absorption properties. For non-biomedical applications, imaging data is usuary obtained only for a limited number of view angles. As a result, we look at the potential of the backpropagation algorithm to reconstruct an image of an object, imbedded in a cloud, from a single view. Using both computer-simulated data and laboratory data, we show that the backpropagation algorithm successfully increases resolution in these types of images. Because the backpropagation algorithm incorporates a depth-dependent deconvolution filter, it turns out that the optimal image quality obtained in the reconstruction occurs for the deconvolution filler which corresponds to the location of the object in the medium. This surprising result permits object localization in the range dimension even when the illuminating radiation is continuous-wave illumination, such as sunlight. C1 USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 USA. RP Matson, CL (reprint author), USAF, Res Lab, DEBS, Kirtland AFB, NM 87117 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3461-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3866 BP 74 EP 81 DI 10.1117/12.371336 PG 8 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BP46D UT WOS:000085206200008 ER PT S AU Grote, JG Drummond, JP AF Grote, JG Drummond, JP BE Feldman, MR Grote, JG HibbsBrenner, MK TI Nonlinear optic polymer core - conductive polymer clad optoelectronic device SO OPTOELETRONIC INTEGRATED CIRCUITS AND PACKAGING III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Optoelectronic Integrated Circuits and Packaging III CY JAN 28-29, 1999 CL SAN JOSE, CA SP SPIE, Def Adv Res Projects Agnecy DE nonlinear optic polymer; optoelectronic; electrooptic; modulator; mach Zehnder AB A scheme for a five volt V pi nonlinear optical (NLO) polymer optoelectronic (OE) device is presented with the potential to realize an interaction length that is about an order of magnitude shorter than conventional five volt V pi NLO polymer OE devices. It utilizes available NLO polymer materials for the core layer and a conductive polymer material for the cladding layers. Since the cladding layer material is more conductive than the core material, most of the applied poling and modulation voltages is dropped across the core layer, rendering a more efficient device. Using an NLO polymer material with electrooptic (EO) coefficients of say 22 pm/V, it is feasible to demonstrate < 2 mm OE devices operating at TTL voltage levels. These small device sizes could lead to use within electronic multichip modules (MCM's). In addition, since the majority of the poling voltage is dropped across the core layer, less voltage is required so that in-situ poling becomes possible. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Grote, JG (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 37 TC 14 Z9 14 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 0-8194-3101-X J9 PROC SPIE PY 1999 VL 3631 BP 86 EP 95 DI 10.1117/12.348299 PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN09U UT WOS:000080681700011 ER PT S AU Soref, RA Friedman, LR Noble, MJ Schwall, D Ram-Mohan, LR AF Soref, RA Friedman, LR Noble, MJ Schwall, D Ram-Mohan, LR BE Feldman, MR Grote, JG HibbsBrenner, MK TI Simulation of integrated silicon-based Ge Si quantum-well-and-superlattice infrared photodetectors SO OPTOELETRONIC INTEGRATED CIRCUITS AND PACKAGING III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Optoelectronic Integrated Circuits and Packaging III CY JAN 28-29, 1999 CL SAN JOSE, CA SP SPIE, Def Adv Res Projects Agnecy DE infrared detectors; germanium; silicon; quantum well; superlattice; imagers; optoelectronic integration; multispectral sensing; uncooled sensors ID INTERSUBBAND ABSORPTION; WAVELENGTH AB We have performed quantum-mechanical analyses of strain-symmetrized Ge/Si QWIPs grown upon a relaxed buffer layer of Si0.4Ge0.6 on Si. The multi-quantum-well (MQW) QWIP has 50 Angstrom-thick compressively strained p-doped Ge quantum wells and 200 Angstrom-thick tensile-strained Si-rich SiGe barriers. This MQW allows shorter-wavelength IR sensing than prior-art unbuffered Si0.64Ge0.36/Si asymmetrically strained QWIPs because the valence band offsets are similar to 3x larger. We predict normal-incidence higher-temperature operation (perhaps uncooled) over the 1.7-to-3.8-mu m wavelength band using the bound-to-bound and bound-to-continuum transitions HH1-SO1 and HH1-SO-C, respectively. We expect that the p-i-p Ge/Si MQW pixels analyzed here can be fashioned into 2D imaging arrays, and that the arrays can be integrated monolithically with Si readout circuitry. We also anticipate that multi-spectral IR imaging will be feasible by the technique of vertical epitaxial stacking of "sub-QWIPS" within each pixel- where each sub-QWIP has a narrowband spectral response that differs from its neighbor's, and each sub-QWIP's electrical readout current is independent of its neighbor's. C1 USAF, Res Lab, AFRL, SNHC,Sensors Directorate, Hanscom AFB, MA 01731 USA. RP Soref, RA (reprint author), USAF, Res Lab, AFRL, SNHC,Sensors Directorate, Hanscom AFB, MA 01731 USA. RI Ram-Mohan, Ramdas/C-5167-2012 NR 13 TC 1 Z9 1 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3101-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3631 BP 113 EP 121 DI 10.1117/12.348302 PG 5 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BN09U UT WOS:000080681700014 ER PT S AU Cooper, TM Fleitz, PA Sowards, LA Natarajan, LV Kirkpatrick, S Chandra, S Spangler, CW AF Cooper, TM Fleitz, PA Sowards, LA Natarajan, LV Kirkpatrick, S Chandra, S Spangler, CW BE Kippelen, B Lackritz, HS Claus, RO TI Two photon spectroscopy of dithienyl polyenes SO ORGANIC NONLINEAR OPTICAL MATERIALS AND DEVICES SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium F on Organic Nonlinear Optical Materials and Devices, at the 1999 MRS Spring Meeting CY APR 06-09, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc ID ABSORPTION AB To understand the properties of light-sensitive compounds used in optical limiters having photoinduced charge transfer mechanisms, we have investigated the photophysics of a series of di(2-thienyl-3,3'-butyl)polyenes, Spectroscopic measurements, including UV/Vis, fluorescence, fluorescence lifetimes, fluorescence quantum yields, triplet state lifetime, solvent effects and two-photon absorption coefficient were obtained as a function of the number of double bonds(n = 1-5). Trends in the data reflected the ordering, energy gap between and mixing of B-1(u)* and (1)A(g)* excited state configurations. C1 USAF, Res Lab, AFRL, MLPJ, Wright Patterson AFB, OH 45433 USA. RP Cooper, TM (reprint author), USAF, Res Lab, AFRL, MLPJ, 3005 P St Ste 1, Wright Patterson AFB, OH 45433 USA. NR 10 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 1-55899-468-8 J9 MATER RES SOC SYMP P PY 1999 VL 561 BP 51 EP 56 PG 6 WC Materials Science, Multidisciplinary; Optics; Polymer Science SC Materials Science; Optics; Polymer Science GA BN69D UT WOS:000082590800009 ER PT S AU Banach, MJ Alexander, MD Caracci, S Vaia, RA AF Banach, MJ Alexander, MD Caracci, S Vaia, RA BE Kippelen, B TI Enhancement of electro-optic coefficient of doped films through optimization of chromophore environment SO ORGANIC PHOTONIC MATERIALS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Organic Photonic Materials and Devices CY JAN 25-27, 1999 CL SAN JOSE, CA SP SPIE, Def Adv Res Projects Agency DE electro-optic; non-linear optical; r(33); guest-host; intermolecular interactions ID GUEST-HOST; POLED POLYMERS; SYSTEMS; SOLVENT; BLENDS AB Substantial (>70%) enhancement of the electro-optic (EO) coefficient of NLO films through optimization of host properties and local chromophore environment is discussed. The EO coefficient (r(33)) was determined for common electrooptic chromophores Disperse Red 1 (DR1) and 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostryl)-4H-pyran (DCM) doped in poly(styrene) (PS), poly(2-vinyl pyridine) (P2VP), poly(methyl methacrylate) (PMMA), poly(cyclohexyl methacrylate), and styrene-methyl methacrylate copolymers. The r(33) varied as much as two orders of magnitude in this series. Resonance enhancement and local field effects account for 20-25% of this variation. The remainder is attributed to intermolecular interactions. Electronic and infrared spectroscopy revealed the presence of specific secondary interactions (H-bonding) between chromophore-host and chromophore-chromophore. These influence the molecular miscibility and thus alter the effective chromophore concentration and therefore the EO coefficient. Additionally, synergy between the chromophore and a field-responsive host facilitates chromophore alignment. A combination of these effects observed in a DR1-P2VP system leads to an enhancement in r(33) by greater then 70% with respect to a comparable DR1-PMMA system. An ultimate EO coefficient of 15 pm/V for a 25wt% DR1-P2VP system was obtained. These results demonstrate the potential associated with modification of guest-host interactions for the development of highly nonlinear, stable EO polymer systems C1 Univ Cincinnati, Cincinnati, OH 45221 USA. RP Vaia, RA (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 29 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 0-8194-3093-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3623 BP 120 EP 129 DI 10.1117/12.348389 PG 10 WC Materials Science, Multidisciplinary; Optics SC Materials Science; Optics GA BN13X UT WOS:000080851500014 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 Radiometric one second camera (ROSCAM) airborne evaluation SO PASSIVE MILLIMETER-WAVE IMAGING TECHNOLOGY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Passive Millimeter-Wave Imaging Technology III CY APR 07, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers DE passive; millimeter wave; one-second camera; radiometric; imaging AB The rapidly developing market for passive millimeter-wave imaging cameras with a frame time of one second or less includes several commercial as well as military applications. A mechanical scanning antenna system has demonstrated the ability to meet a one second frame time for a 1000 pixel scene, using only one receiving channel. That camera has been updated to provide an airborne imaging capability, in both a raster scanning mode, and a cross-track in-flight mode. The results of a helicopter test program will be described. 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 4 TC 11 Z9 11 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 0-8194-3177-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3703 BP 2 EP 12 DI 10.1117/12.352993 PG 11 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN53H UT WOS:000082158200001 ER PT S AU Huddleston, D Savage, J Sundstrom, B Belcher, B Ewen, D AF Huddleston, D Savage, J Sundstrom, B Belcher, B Ewen, D BE Smith, RM TI Radarometer sensor: simultaneous active and passive imaging using a common antenna SO PASSIVE MILLIMETER-WAVE IMAGING TECHNOLOGY III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Passive Millimeter-Wave Imaging Technology III CY APR 07, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers DE passive; active; millimeter wave; camera; radiometer; radar; data fusion AB The ability to obtain simultaneous active and passive millimeter wave images using a common antenna has numerous DOD as well as commercial applications. Radiometric and radar images are not new, nor are simultaneous passive and active images of a common scene. The feature that is unique to the radarometer concept is simultaneous use of the same antenna by a radar and a radiometer, operating in the same frequency band at a nominal pixel scanning rate of 1,000 per second. The radarometer sensor is capable of operating in both the passive and active modes either individually, in time sequence, or simultaneously. The radarometer uses a common high-speed mechanically scanned antenna aperture capable of generating active and passive millimeter wave images simultaneously. The important feature of the radarometer design that allows simultaneous active and passive operation is the use of an RF diplexer which separates the signals associated with the radar and radiometer modes. The typical frequency separation displacement is 5 GHz, at a nominal operating frequency of 95 GHz. The results of measurements performed on an engineering test unit will be described. C1 USAF, Res Lab, Munit Directorate, Adv Guidance Div, Eglin AFB, FL 32542 USA. RP Huddleston, D (reprint author), USAF, Res Lab, Munit Directorate, Adv Guidance Div, Eglin AFB, FL 32542 USA. NR 1 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 0-8194-3177-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3703 BP 33 EP 44 DI 10.1117/12.353008 PG 12 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN53H UT WOS:000082158200005 ER PT J AU Keller, JG Rogers, SK Kabrisky, M Oxley, ME AF Keller, JG Rogers, SK Kabrisky, M Oxley, ME TI Object recognition based on human saccadic behaviour SO PATTERN ANALYSIS AND APPLICATIONS LA English DT Article DE computer vision; object recognition; saccadic behaviour ID EYE-MOVEMENTS; VISION; ARCHITECTURE; ATTENTION; MODEL AB The automated recognition of targets in complex backgrounds is a difficult problem, yet humans perform such tasks with ease. We therefore propose a recognition model based on behavioural and physiological aspects of the human visual system. Emulating saccadic behaviour, an object is First memorised as a sequence of fixations. At each fixation an artificial visual field is constructed using a multi resolution/orientation Gabor filterbank, edge features are extracted, and a new saccadic location is automatically selected. When a new image is scanned and a 'familiar' field of view encountered, the memorised saccadic sequence is executed over the new image. If the expected visual field is found around each fixation point, the memorised object is recognised. Results are presented from trials in which individual objects were first memorised and then searched for in collages of similar objects acting as distracters. In the different collages, entries of the memorised objects were subjected to various combinations of rotation, translation and noise corruption. The model successfully detected the memorised object in over 93% of the 'object present' trials, and correctly rejected collages in over 98% of the trials in which the object was not present in the collage. These results are compared with those obtained using a correlation-based recogniser, and the behavioural model is found to provide superior performance. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. Battelle Mem Inst, Columbus, OH 43201 USA. RP Keller, JG (reprint author), Qualia Comp Inc, 2372 Lakeview Dr,Ste G, Beavercreek, OH 45431 USA. NR 42 TC 3 Z9 3 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1433-7541 J9 PATTERN ANAL APPL JI Pattern Anal. Appl. PY 1999 VL 2 IS 3 BP 251 EP 263 DI 10.1007/s100440050033 PG 13 WC Computer Science, Artificial Intelligence SC Computer Science GA 256CF UT WOS:000083707500005 ER PT S AU Mayfield, HT Eastwood, D Burggraf, LW AF Mayfield, HT Eastwood, D Burggraf, LW BE Siddiqui, KJ Eastwood, D TI Classification of infrared spectra of organophosphorus compounds with artificial neural networks SO PATTERN RECOGNITION, CHEMOMETRICS, AND IMAGING FOR OPTICAL ENVIRONMENTAL MONITORING SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Pattern Recognition, Chemometrics, and Imaging for Optical Environmental Monitoring CY SEP 20-21, 1999 CL BOSTON, MA SP SPIE, Air & Waste Management Assoc, Opt Sci Div DE infrared spectroscopy; organophosphorus compounds; pesticides; classification; chemometrics; pattern recognition; artificial neural networks; radial basis function networks ID ALGORITHM AB We examine the use of artificial neural networks to classify infrared spectra of organophosphorus pesticides and chemically related compounds. The spectra used were contributed from commercial libraries, government agencies, and government contractors and include spectra of pesticides, industrial precursors, hydrolysis products and other organophosphorus compounds. The data were pretreated to reduce artifacts arising from the variety of collection sources. The treated spectra were divided into spectral "bins" of equal frequency width and transduced into data vectors whose elements consisted of the average absorbance value of the corresponding spectral bin, The spectral data vectors served as inputs to neural networks examined as spectral classifiers. Conventional feed-forward neural networks were constructed using the spectral data vectors as inputs and indicating the chemical class in the output nodes. Several training methods were compared for efficiency in setting the network weights and biases, from the standpoint of time needed to train the network and from the error frequencies obtained Network architecture was also examined in order to obtain the optimum number of nodes to place in the hidden layers of the networks. Radial basis function networks were also generated from spectral input data and used to classify the spectra. The final classification accuracies and training efficiencies from these networks were compared with those from the feed forward networks. The radial basis function networks could be trained rapidly and produced numerically stable networks, but the network generation technique tended to produce large numbers of hidden nodes. The radial basis function networks gave the best classification accuracy obtained with neural network classifiers. C1 USAF, Res Lab, Airbase & Environm Technol Div, Tyndall AFB, FL 32403 USA. RP Mayfield, HT (reprint author), USAF, Res Lab, Airbase & Environm Technol Div, 139 Barnes Dr,Suite 2, Tyndall AFB, FL 32403 USA. NR 18 TC 1 Z9 1 U1 1 U2 2 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3447-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3854 BP 56 EP 64 DI 10.1117/12.372886 PG 9 WC Computer Science, Artificial Intelligence; Environmental Sciences; Instruments & Instrumentation; Remote Sensing; Optics SC Computer Science; Environmental Sciences & Ecology; Instruments & Instrumentation; Remote Sensing; Optics GA BP39P UT WOS:000084986300007 ER PT J AU De Witt, CC Ascher, DP Winkelstein, J AF De Witt, CC Ascher, DP Winkelstein, J TI Group B streptococcal disease in a child beyond early infancy with a deficiency of the second component of complement (C2) SO PEDIATRIC INFECTIOUS DISEASE JOURNAL LA English DT Article DE group B Streptococcus; C2 deficiency; complement deficiency ID EPIDEMIOLOGY C1 Wilford Hall USAF Med Ctr, Dept Med, Div Infect Dis, Infect Dis Serv, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Pediat, Lackland AFB, TX 78236 USA. Johns Hopkins Hosp, Dept Pediat, Eudowood Div Immunol, Baltimore, MD 21287 USA. RP De Witt, CC (reprint author), Wilford Hall USAF Med Ctr, Dept Med, Div Infect Dis, Infect Dis Serv, 2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 9 TC 4 Z9 4 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0891-3668 J9 PEDIATR INFECT DIS J JI Pediatr. Infect. Dis. J. PD JAN PY 1999 VL 18 IS 1 BP 77 EP 78 DI 10.1097/00006454-199901000-00024 PG 2 WC Immunology; Infectious Diseases; Pediatrics SC Immunology; Infectious Diseases; Pediatrics GA 159QU UT WOS:000078185900023 PM 9951992 ER PT J AU Beer, J Previc, F Blakemore, C Liotti, M AF Beer, J. Previc, F. Blakemore, C. Liotti, M. TI Functional imaging of brain areas involved in the wide-field visual processing of continuous linear self-motion SO PERCEPTION LA English DT Meeting Abstract C1 [Beer, J.; Previc, F.] USAF, Flight Mot Effects, Veridian Inc, Res Lab, Brooks AFB, TX 78235 USA. [Blakemore, C.] Univ Oxford, Univ Lab Physiol, Oxford OX1 3PT, England. [Liotti, M.] Univ Texas Hlth Sci Ctr San Antonio, San Antonio, TX 78229 USA. EM Jeremy.Beer@afrlars.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 1999 VL 28 SU S BP 93 EP 93 PG 1 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA V17AQ UT WOS:000207910500296 ER PT J AU Hershenson, M Samuels, SM AF Hershenson, M Samuels, SM TI An airplane illusion: apparent velocity determined by apparent distance SO PERCEPTION LA English DT Article ID CONSTANCY AB When a small drone plane appears to be a normal-sized airplane, it appears to be very far away and moving too fast. This is the airplane illusion. In the illusory situation, familiar size determines the apparent size and distance of the plane. It sets the depth for the frontal-plane component of the perceived motion and the relative depth difference for the motion-in-depth component. Because these perceived distances are very large, the perceived velocities are very large in the respective directions. Cognition can override familiarity and produce a veridical perception of the drone. C1 Brandeis Univ, Dept Psychol, Waltham, MA 02254 USA. USAF Acad, HQ USAFA, DFBL, Colorado Springs, CO 80840 USA. RP Hershenson, M (reprint author), Brandeis Univ, Dept Psychol, Waltham, MA 02254 USA. NR 9 TC 5 Z9 5 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 1999 VL 28 IS 4 BP 433 EP 436 DI 10.1068/p2779 PG 4 WC Ophthalmology; Psychology; Psychology, Experimental SC Ophthalmology; Psychology GA 214DW UT WOS:000081313200003 PM 10664784 ER PT J AU Watson, SE Kramer, AF AF Watson, SE Kramer, AF TI Object-based visual selective attention and perceptual organization SO PERCEPTION & PSYCHOPHYSICS LA English DT Article ID SIDED EDGE ASSIGNMENT; HIERARCHICAL STRUCTURE; SPATIAL ATTENTION; GLOBAL FEATURES; LOCAL-LEVELS; LOCATIONS; RECOGNITION; NEGLECT; FIELD; TASK AB We report the results of four experiments that were conducted to examine both the representations that provide candidate entities available for object-based attentional selection and the influence of bottom-up factors (i.e., geometric and surface characteristics of objects) and top-down factors (i.e,, context and expectancies) on the selection process. Subjects performed the same task in each of the experiments. They were asked to determine whether two target properties, a bent end and an open end of a wrench, appeared in a brief display of two wrenches. In each experiment, Me target properties could occur on a single wrench or one property could occur on each of two wrenches. The question of central interest was whether a same-object effect (faster and/or more accurate performance when the target properties appeared on one vs. two wrenches) would be observed in different, experimental conditions. Several interesting results were obtained. First, depending on the geometric (i.e., concave discontinuities on object contours) and surface characteristics (i.e., homogeneous regions of color and texture) of the stimuli, attention was preferentially directed to one of three representational levels, as indicated by the presence or absence of the same-object effect. Second, although geometric and surface characteristics defined the candidate objects available for attentional selection, top-down factors were quite influential in determining which representational level would be selected. Third, the results suggest that uniform connectedness plays an important role in defining the entities available for attention selection. These results are discussed in terms of the manner in which attention selects objects in the visual environment. C1 Armstrong Lab, Brooks AFB, TX 78235 USA. Univ Illinois, Beckman Inst, Urbana, IL 61801 USA. RP Watson, SE (reprint author), Armstrong Lab, Brooks AFB, TX 78235 USA. EM watson@alhem.brooks.af.mil; akramer@s.psych.uiuc.edu NR 78 TC 124 Z9 127 U1 4 U2 13 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 USA SN 0031-5117 J9 PERCEPT PSYCHOPHYS JI Percept. Psychophys. PD JAN PY 1999 VL 61 IS 1 BP 31 EP 49 DI 10.3758/BF03211947 PG 19 WC Psychology; Psychology, Experimental SC Psychology GA 164HX UT WOS:000078458800004 PM 10070198 ER PT J AU Fowler, CB AF Fowler, CB TI Benign and malignant neoplasms of the periodontium SO PERIODONTOLOGY 2000 LA English DT Review ID SQUAMOUS-CELL CARCINOMA; PROLIFERATIVE VERRUCOUS LEUKOPLAKIA; CENTRAL ODONTOGENIC FIBROMA; NON-HODGKINS-LYMPHOMA; HUMAN PAPILLOMAVIRUS DNA; ACQUIRED IMMUNODEFICIENCY SYNDROME; SARCOMA-ASSOCIATED HERPESVIRUS; INSITU HYBRIDIZATION ANALYSIS; ACUTE LYMPHOBLASTIC-LEUKEMIA; JUVENILE OSSIFYING FIBROMA C1 Wilford Hall USAF Med Ctr, Oral Serv, San Antonio, TX 78236 USA. Wilford Hall USAF Med Ctr, Maxillofacial Pathol Serv, San Antonio, TX 78236 USA. RP Fowler, CB (reprint author), Wilford Hall USAF Med Ctr, Oral Serv, San Antonio, TX 78236 USA. NR 376 TC 4 Z9 4 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0906-6713 J9 PERIODONTOL 2000 JI Periodontol. 2000 PY 1999 VL 21 BP 33 EP 83 DI 10.1111/j.1600-0757.1999.tb00168.x PG 51 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 234ML UT WOS:000082488400003 PM 10551175 ER PT S AU Fiedler, CJ Wagner, JW AF Fiedler, CJ Wagner, JW BE Scudieri, F Bertolotti, M TI Thin film characterization using high frequency laser based ultrasound SO PHOTOACOUSTIC AND PHOTOTHERMAL PHENOMENA: TENTH INTERNATIONAL CONFERENCE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 10th International Conference on Photoacoustic and Photothermal Phenomena CY AUG 23-27, 1998 CL ROME, ITALY SP Univ Tor Vergata, Univ La Sapienza, Gruppo Nazl Elettronica Quantistica Plasmi, Gruppo Nazl Cibernetica Biofisica, Ist Nazl Fisica Mat, European Union, Soc Italiana Ottica Fotonica, Banca Roma, Tourist Off Rome AB A novel delay line based interferometer has been developed for detecting the high frequency pulses of ultrasound which are used to characterize thin films. Ultrafast pulses of laser light are used to generate high frequency pulses of ultrasound which are detected using the interferometer. Ultrasonic echoes in 30 nm thick gold films which are not detectable using piezoreflective detection are detectable using this interferometer. C1 USAF, Res Labs, Mat & Mfg Directorate, Div Met & Ceram, Wright Patterson AFB, OH 45433 USA. RP Fiedler, CJ (reprint author), USAF, Res Labs, Mat & Mfg Directorate, Div Met & Ceram, Wright Patterson AFB, OH 45433 USA. NR 3 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 1-56396-805-3 J9 AIP CONF PROC PY 1999 VL 463 BP 411 EP 414 DI 10.1063/1.58098 PG 4 WC Engineering, Biomedical; Food Science & Technology; Instruments & Instrumentation; Materials Science, Characterization & Testing; Microscopy; Multidisciplinary Sciences; Optics; Physics, Applied; Spectroscopy SC Engineering; Food Science & Technology; Instruments & Instrumentation; Materials Science; Microscopy; Science & Technology - Other Topics; Optics; Physics; Spectroscopy GA BM77V UT WOS:000079746800126 ER PT S AU Smith, G Estes, MJ Van Nostrand, J Dang, T Schreiber, PS Temkin, H Hoelscher, J AF Smith, G Estes, MJ Van Nostrand, J Dang, T Schreiber, PS Temkin, H Hoelscher, J BE Brown, GJ Razeghi, M TI UV Schottky-barrier detector development for possible air force applications SO PHOTODETECTORS: MATERIALS AND DEVICES IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Photodetectors - Materials and Devices IV CY JAN 27-29, 1999 CL SAN JOSE, CA SP SPIE, Denfense Adv Res Projects Agcy DE ultraviolet detectors; Schottky-barrier detectors; gallium nitride; palladium ID ULTRAVIOLET PHOTODETECTORS; GAN; NOISE; EPITAXY AB This paper discusses the collaborative optical and electrical characterization of the first photovoltaic (PV) m-nitride based detectors grown and fabricated by the Air Force Research Laboratory (AFRL). These 2.6 um thick, n-type GaN Schottky detector structures doped with Si were grown by molecular beam epitaxy (MBE) on (0001)-oriented sapphire substrates, and incorporated palladium (Pd) as the Schottky metal contact. Working Schottky-barrier detector sizes ranged from 50 mu m to 1600 mu m in diameter. Flood-illuminated spectral responsivities of these Schottky detectors were as high as 0.12 A/W (for a 1600 mu m diameter device biased at -1.5V) at a peak wavelength of 273nm. The typical measured frequency response of these detectors was flat from de to the chopper limit of 700Hz, and the 1/e response time of a 1600 mu m diameter Schottky-barrier GaN detector was found to be as low as 50 mu s at zero bias. Noise characterization of these detectors was also performed, and noise equivalent powers (NEPs) of sample GaN Schottky-barrier detectors are reported. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Smith, G (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 10 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 0-8194-3099-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3629 BP 184 EP 192 DI 10.1117/12.344588 PG 9 WC Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics; Physics, Applied SC Instruments & Instrumentation; Materials Science; Optics; Physics GA BN06E UT WOS:000080521800017 ER PT S AU Saxler, A Ahoujja, M Mitchel, WC Kung, P Walker, D Razeghi, M AF Saxler, A Ahoujja, M Mitchel, WC Kung, P Walker, D Razeghi, M BE Brown, GJ Razeghi, M TI Electrical characterization of AlxGa1-xN for UV photodetector applications SO PHOTODETECTORS: MATERIALS AND DEVICES IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Photodetectors - Materials and Devices IV CY JAN 27-29, 1999 CL SAN JOSE, CA SP SPIE, Denfense Adv Res Projects Agcy DE GaN; gallium nitride; AlGaN; aluminum gallium nitride; Hall effect; ultraviolet photodetectors; short-period superlattice; p-type doping; magnesium doping ID CHEMICAL-VAPOR-DEPOSITION; STRUCTURE LASER-DIODES; DOPED GAN; SAPPHIRE; GROWTH; FILMS; ALGAN AB Ultraviolet photodetectors have many military and commercial applications. However, for many of these applications, the photodetectors must be solar blind. This means that the photodetectors must have a cutoff wavelength of less than about 270 nm. Semiconductor based devices would then need energy gaps of over 4.6 eV. In the AlxGa1-xN system, the aluminum mole fraction, x, required is over 40%. As the energy gap is increased, doping becomes much more difficult, especially p-type doping. This report is a study of the electrical properties of AlxGa1-xN to enable better control of the doping. Magnesium doped p-type AlxGa1-xN has been studied using high-temperature Hall effect measurements. The acceptor ionization energy has been found to increase substantially with the aluminum content. Short-period superlattices consisting of alternating layers of GaN:Mg and AlGaN:Mg were also grown by low-pressure organometallic vapor phase epitaxy. The electrical properties of these superlattices were measured as a function of temperature and compared to conventional AlGaN:Mg layers. It is shown that the optical absorption edge can be shifted to shorter wavelengths while lowering the acceptor ionization energy by using short-period superlattice structures instead of bulk-like AlGaN:Mg. Silicon doped n-type films have also been studied. C1 USAF, Res Lab, Mat & Mfg Directorate, Sensor Mat Branch, Wright Patterson AFB, OH 45433 USA. RP Saxler, A (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Sensor Mat Branch, Wright Patterson AFB, OH 45433 USA. NR 21 TC 2 Z9 2 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 0-8194-3099-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3629 BP 211 EP 222 DI 10.1117/12.344558 PG 12 WC Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics; Physics, Applied SC Instruments & Instrumentation; Materials Science; Optics; Physics GA BN06E UT WOS:000080521800020 ER PT S AU Schreiber, P Dang, T Pickenpaugh, T Smith, G Gehred, P Litton, C AF Schreiber, P Dang, T Pickenpaugh, T Smith, G Gehred, P Litton, C BE Brown, GJ Razeghi, M TI Solar blind UV region and UV detector development objectives SO PHOTODETECTORS: MATERIALS AND DEVICES IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Photodetectors - Materials and Devices IV CY JAN 27-29, 1999 CL SAN JOSE, CA SP SPIE, Denfense Adv Res Projects Agcy DE solar-blind UV region; UV detector development objectives AB The vulnerability of aircraft to missile attacks is briefly sketched. Aircraft and helicopter defensive electronic self-protection systems against missile attacks including passive and active radar and IR countermeasures are summarized. Radar and IR missile threat warnings are outlined. The development of UV missile threat warning is recounted. UV missile warning coverage is defined. UV missile plume photon emission is addressed. Solar UV emission and atmospheric transmission is reviewed. An AF atmospheric computer program called PLEXUS is applied to the UV spectral region to obtain the atmospheric transmission along paths extending from the upper atmosphere to the lower atmosphere. These atmospheric transmission numbers are used to evaluate the number of solar photons propagating through the upper atmosphere to lower tactical altitudes and into an UV missile-warning sensor viewing the sun directly. These numerical evaluations are accomplished in one-nanometer wide wavelength bins. The results are presented in a number of figures, which then serve to define the solar blind UV region. Detector spectral development objectives are then presented based on the results shown in the figures. C1 USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Schreiber, P (reprint author), USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. NR 10 TC 53 Z9 54 U1 1 U2 11 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3099-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3629 BP 230 EP 248 DI 10.1117/12.344560 PG 19 WC Instruments & Instrumentation; Materials Science, Characterization & Testing; Optics; Physics, Applied SC Instruments & Instrumentation; Materials Science; Optics; Physics GA BN06E UT WOS:000080521800022 ER PT S AU Hayduk, MJ Bernstein, NP Haus, JW Taylor, EW AF Hayduk, MJ Bernstein, NP Haus, JW Taylor, EW BE Taylor, EW Berghmans, F TI Radiation effects in RF photonic components for space based applications SO PHOTONICS FOR SPACE AND RADIATION ENVIRONMENTS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 1st Conference on Photonics for Space and Enhanced Radiation Environments CY SEP 20-21, 1999 CL UNIV FLORENCE, FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy HO UNIV FLORENCE DE fiber laser; analog to digital converters; saturable absorber; pulse propagation; modelocking; space radiation environments ID DIGITAL CONVERTER; MODE-LOCKING; SOLITON AB This paper describes the development of compact, polarization insensitive mode-locked erbium-doped fiber lasers producing picosecond pulses for use as optical sampling sources in photonic analog to digital converters (ADCs). High-sampling rate and high resolution ADCs are required to convert the 'naturally occurring' received analog signals to digital signals suitable for on-board data processing. The laser was constructed in a linear cavity, Fabry-Perot configuration with the saturable absorber at one end of the cavity and a chirped fiber Bragg grating at the other end. Theoretical modeling of the pulse formation within the laser cavity is presented and is in close agreement with the experimental data. The influence of radiation effects on erbium-doped fiber and fiber Bragg gratings is also investigated. C1 USAF, Res Lab, Sensors Directorate, Rome, NY 13441 USA. RP Hayduk, MJ (reprint author), USAF, Res Lab, Sensors Directorate, 25 Electron Pkwy, Rome, NY 13441 USA. NR 10 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 0-8194-3467-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3872 BP 108 EP 117 DI 10.1117/12.373275 PG 10 WC Astronomy & Astrophysics; Optics SC Astronomy & Astrophysics; Optics GA BP46H UT WOS:000085207000012 ER PT J AU Takekoshi, T Patterson, BM Knize, RJ AF Takekoshi, T Patterson, BM Knize, RJ TI Observation of cold ground-state cesium molecules produced in a magneto-optical trap SO PHYSICAL REVIEW A LA English DT Article ID ATOMS AB We have observed translationally cold electronic ground-state cesium dimers produced directly in a magneto-optical trap and also by photoassociation of cold atoms in this trap. These neutral molecules were detected using photoionization and time-of-flight spectroscopy. Initial experiments indicated a cold molecular formation rate of about 600 s(-1), with no photoassociation laser present. The measured translational temperature of the neutral cesium dimers was approximately 100 mu K. [S1050-2947(99)50401-0]. C1 USAF Acad, Dept Phys, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. RP Takekoshi, T (reprint author), USAF Acad, Dept Phys, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. NR 12 TC 42 Z9 42 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JAN PY 1999 VL 59 IS 1 BP R5 EP R7 DI 10.1103/PhysRevA.59.R5 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 158JD UT WOS:000078111500002 ER PT J AU Ross, M AF Ross, M TI Delayed-onset muscle soreness - Work out now, pay later? SO PHYSICIAN AND SPORTSMEDICINE LA English DT Article C1 USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. RP Ross, M (reprint author), USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU MCGRAW HILL HEALTHCARE PUBLICATIONS PI MINNEAPOLIS PA 4530 WEST 77TH ST, MINNEAPOLIS, MN 55435-5000 USA SN 0091-3847 J9 PHYSICIAN SPORTSMED JI Physician Sportsmed. PD JAN PY 1999 VL 27 IS 1 BP 107 EP 108 PG 2 WC Primary Health Care; Orthopedics; Sport Sciences SC General & Internal Medicine; Orthopedics; Sport Sciences GA 156CM UT WOS:000077983900014 PM 20086674 ER PT S AU Noble, MJ Loehr, JP Lott, JA AF Noble, MJ Loehr, JP Lott, JA BE Blood, P Ishibashi, A Osinski, M TI Comparison of optical analysis methods for oxide-apertured VCSELs SO PHYSICS AND SIMULATION OF OPTOELECTRONIC DEVICES VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Physics and Simulation of Optoelectronic Devices VII CY JAN 25-29, 1999 CL SAN JOSE, CA SP SPIE, Def Adv Res Projects Agcy ID SURFACE-EMITTING LASERS; VERTICAL-CAVITY LASERS; MICROCAVITY LASERS; CONFINEMENT; MIRRORS AB We present a comparison between a semi-analytic parasitic mode weighted index method and a quasi-exact vector finite element method. We derive the parasitic mode weighted index method by augmenting the older weighted index method to capture diffraction. Diffraction is included by coupling the weighted index eigenmode to a set of resonant parasitic modes. We apply both techniques to an oxide-apertured, oxide-DBR VCSEL to compute the lasing mode wavelength, threshold gain, and transverse confinement factor. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. RP Noble, MJ (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 21 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 0-8194-3095-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3625 BP 359 EP 370 DI 10.1117/12.356895 PG 12 WC Optics SC Optics GA BN77L UT WOS:000082883300038 ER PT S AU Sukow, DW Heil, T Fischer, I Gavrielides, A Hohl, A Elsasser, W AF Sukow, DW Heil, T Fischer, I Gavrielides, A Hohl, A Elsasser, W BE Blood, P Ishibashi, A Osinski, M TI Statistical studies of semiconductor lasers with delayed optical feedback SO PHYSICS AND SIMULATION OF OPTOELECTRONIC DEVICES VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Physics and Simulation of Optoelectronic Devices VII CY JAN 25-29, 1999 CL SAN JOSE, CA SP SPIE, Def Adv Res Projects Agcy DE external cavity semiconductor lasers; low-frequency fluctuations ID POWER-DROPOUT EVENTS; COHERENCE COLLAPSE; CHAOTIC ITINERANCY; DYNAMICS AB We investigate the statistics of the irregular fast pulsing intensity dynamics of semiconductor lasers with delayed optical feedback operating in the low-frequency fluctuation and coherence collapse regimes. We demonstrate experimentally that the probability density distributions of the laser intensity on a picosecond timescale do not depend on the number of optical modes involved in the laser emission, using two complementary high-resolution experimental measurement systems: a high-bandwidth sampling digitizer and a single shot streak camera. The experimental. results are in agreement with numerical results based on the Lang-Kobayashi equations. C1 USAF, Res Lab, Nonlinear Opt Ctr, DELO, Kirtland AFB, NM 87117 USA. RP Sukow, DW (reprint author), USAF, Res Lab, Nonlinear Opt Ctr, DELO, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. RI Fischer, Ingo/C-2843-2011 OI Fischer, Ingo/0000-0003-1881-9842 NR 16 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 0-8194-3095-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3625 BP 668 EP 678 DI 10.1117/12.356926 PG 11 WC Optics SC Optics GA BN77L UT WOS:000082883300068 ER PT S AU Sukow, DW Kovanis, V Gavrielides, A AF Sukow, DW Kovanis, V Gavrielides, A BE Blood, P Ishibashi, A Osinski, M TI Investigation of coupled diode laser dynamics using an electronic analog SO PHYSICS AND SIMULATION OF OPTOELECTRONIC DEVICES VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Physics and Simulation of Optoelectronic Devices VII CY JAN 25-29, 1999 CL SAN JOSE, CA SP SPIE, Def Adv Res Projects Agcy DE coupled semiconductor lasers; nonlinear dynamics; phase-locked loops ID INJECTED SEMICONDUCTOR-LASER; PHASE-LOCKED LOOPS; SYNCHRONIZATION; STABILITY; CHAOS; NETWORKS; LOCKING; STATES AB We study the behavior of coupled semiconductor lasers using a reduced phase model that captures their essential dynamics yet remains analytically tractable. We design a simple electronic circuit analog, a phase-locked loop, to investigate the system. The circuit offers important experimental advantages, since it operates with slower speeds than a comparable laser system, and has easily tunable parameters. This study reveals new and unexpected period-three states, which we also consider theoretically. C1 USAF, Nonlinear Opt Ctr, Kirtland AFB, NM 87117 USA. RP Sukow, DW (reprint author), USAF, Nonlinear Opt Ctr, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 19 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 0-8194-3095-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3625 BP 778 EP 788 DI 10.1117/12.356939 PG 11 WC Optics SC Optics GA BN77L UT WOS:000082883300080 ER PT S AU Goldstein, DH Chenault, DB Pezzaniti, L AF Goldstein, DH Chenault, DB Pezzaniti, L BE Goldstein, DH Chenault, DB TI Polarimetric characterization of Spectralon SO POLARIZATION: MEASUREMENT, ANALYSIS, AND REMOTE SENSING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Polarization - Measurement, Analysis, and Remote Sensing II CY JUL 19-21, 1999 CL DENVER, CO SP SPIE DE polarimetry; spectropolarimeter; Mueller matrix; Spectralon; polarizance ID MUELLER MATRIX; REFLECTANCE; SPECTROPOLARIMETRY; CALIBRATION AB A polarimetric characterization of the reflective standard material Spectralon is presented. Samples of Spectralon with reflectances of 2%, 50%, 75% and 99% were examined. The characterization was accomplished using the Air Force Research Laboratory's spectropolarimeter in reflection mode. Data are presented for the spectral region .65 to 1.0 micrometers. Polarizance was measured for the four Spectralon samples at eight input beam incidence angles. All observations were made from normal to the Spectralon. It was found that as the incidence beam angle increases, the polarizance increases; and as the reflectance of the sample decreases, the polarizance increases. C1 USAF, Res Lab, Eglin AFB, FL 32542 USA. RP Goldstein, DH (reprint author), USAF, Res Lab, 101 W Eglin Blvd, Eglin AFB, FL 32542 USA. NR 13 TC 8 Z9 9 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 0-8194-3240-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3754 BP 126 EP 136 DI 10.1117/12.366323 PG 11 WC Instruments & Instrumentation; Remote Sensing; Optics SC Instruments & Instrumentation; Remote Sensing; Optics GA BP12A UT WOS:000084180100014 ER PT S AU Gamiz, VL Belsher, JF AF Gamiz, VL Belsher, JF BE Goldstein, DH Chenault, DB TI Performance limitations of a four channel polarimeter in the presence of detection SO POLARIZATION: MEASUREMENT, ANALYSIS, AND REMOTE SENSING II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Polarization - Measurement, Analysis, and Remote Sensing II CY JUL 19-21, 1999 CL DENVER, CO SP SPIE DE polarized light; polarimetry; Stokes parameters; Mueller calculus; statistical optics; low light level detection AB We examine the performance limitations of a four-channel polarimeter in the presence of detection noise for arbitrary light levels. We treat the case where the light exciting the polarimeter is detected by a photon counting sensor at each of the four channels. Specifically, we theoretically describe the propagation of detection noise through the polarimeter calibration matrix. The variances in the four estimated Stokes vector components, both orthogonal intensities and mutual phase delay are theoretically predicted for photon counting noise following Poison statistics, and additive Gaussian detection noise. The variances of these parameters depend on the average number of photons incident on the polarimeter, the root-mean-square read noise, and the polarimeter calibration matrix. This methodology allows for including fixed errors in the polarimeter calibration matrix. Various polarimeter designs, whose calibration matrices are known exactly, are examined for high, low and very low light levels. Theoretical performance curves are shown for various sensor parameters and light levels. The theoretically predicted values are compared to simulated results. Excellent agreement between theory and simulation is shown. The simulation also:validates the use of the Gaussian probability density function for the parallel (in-phase) and normal components of the phase fluctuations. and results in an accurate theoretical prediction of phase:delay fluctuations for arbitrary light levels. The phase;delay noise cloud is illustrated for several cases. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Gamiz, VL (reprint author), USAF, Res Lab, AFRL DEBS Bldg,3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 5 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 0-8194-3240-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3754 BP 204 EP 216 DI 10.1117/12.366356 PG 13 WC Instruments & Instrumentation; Remote Sensing; Optics SC Instruments & Instrumentation; Remote Sensing; Optics GA BP12A UT WOS:000084180100023 ER PT S AU Aranda, FJ Harris, MT Callahan, MJ Bailey, JS Suscavage, MJ Bliss, DF Kimball, BR Nakashima, M DeCristofano, B Rao, DVGLN AF Aranda, FJ Harris, MT Callahan, MJ Bailey, JS Suscavage, MJ Bliss, DF Kimball, BR Nakashima, M DeCristofano, B Rao, DVGLN BE Lawson, CM TI Optical power limiting in ZnO crystals SO POWER-LIMITING MATERIALS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Power-Limiting Materials and Devices CY JUL 21-22, 1999 CL DENVER, CO SP SPIE AB We report optical power limiting in undoped single crystals of the wide band-gap semiconductor Zinc Oxide (ZnO), The ZnO crystals were grown at the Sensors Directorate of the Air Force Research Laboratory using the hydrothermal method. The crystals are of high optical quality and are transparent in the visible part of the spectrum. The contributions of the real and imaginary parts of the third-order nonlinear optical susceptibility were studied using the Z-scan technique. The Z-scan experiments were carried out using picosecond pulses at 532 nm wavelength with the electric field polarization oriented orthogonal to the crystal c-axis. The nonlinear refractive index of the crystals is found to be negative. The ZnO samples exhibit two photon absorption and high damage thresholds. Our results indicate that the ZnO crystals may be good candidates for applications in optical power limiting and pulse stabilization. C1 USAF, Res Lab, SNHX, Bedford, MA 01731 USA. RP Aranda, FJ (reprint author), USAF, Res Lab, SNHX, 80 Scott Rd, Bedford, MA 01731 USA. NR 9 TC 6 Z9 6 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 0-8194-3284-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3798 BP 22 EP 31 DI 10.1117/12.363878 PG 10 WC Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BN98F UT WOS:000083742600003 ER PT S AU Cooper, TM Sowards, LA Natarajan, LV Kirkpatrick, SM Chandra, S McLean, DG Spangler, CW AF Cooper, TM Sowards, LA Natarajan, LV Kirkpatrick, SM Chandra, S McLean, DG Spangler, CW BE Lawson, CM TI Spectroscopic investigations of dithienyl polyenes SO POWER-LIMITING MATERIALS AND DEVICES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Power-Limiting Materials and Devices CY JUL 21-22, 1999 CL DENVER, CO SP SPIE DE dithienyl polyenes; two photon absorption; solvatochromism; fluorescence; triplet state ID LINEAR POLYENES; ABSORPTION AB To understand the photophysics of nonlinear absorbers, we have investigated the photophysics of a series of di(2-thienyl-3,3',4,4'-butyl)polyenes. Spectroscopic measurements, including UV/Vis, fluorescence, fluorescence lifetimes, fluorescence quantum yields, triplet state lifetime, solvent effects and two-photon absorption coefficient were obtained as a function of the number of double bonds(n = 1-5). Trends in the data reflected the ordering, energy gap between and mixing of B-1(u)* and (1)A(g)* excited state configurations. We investigated the solvatochromism of a series of alpha,omega-di(2-dithienyl 3,3',4,4'-butyl) polyenes. Absorption (n=1-5 double bonds) and emission spectra(n=1-4 double bands) were collected in a series of aprotic solvents. The absorption energy dispersion effect sensitivity increased smoothly with n, reaching asymptotic behavior as n approached 5. The emission energy had less solvent sensitivity, giving evidence for a polar B-1(u)* absorbing state and a nonpolar (1)A(g)* emitting state. We observed sensitivity of the absorbing and emitting states to solute-solvent dipole-dipole interactions, suggesting the dithienyl polyenes had a polar syn ground state conformation. C1 USAF, Res Lab, AFRL MLPJ, Wright Patterson AFB, OH 45433 USA. RP Cooper, TM (reprint author), USAF, Res Lab, AFRL MLPJ, 3005 P St Ste 1, Wright Patterson AFB, OH 45433 USA. NR 16 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3284-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3798 BP 166 EP 175 DI 10.1117/12.363877 PG 10 WC Materials Science, Characterization & Testing; Optics SC Materials Science; Optics GA BN98F UT WOS:000083742600020 ER PT B AU Griffin, S Huybrechts, S Lane, SA AF Griffin, S Huybrechts, S Lane, SA BE Douglas, S TI Coupled Helmholtz resonators for broadband acoustic attenuation SO PROCEEDINGS OF ACTIVE 99: THE INTERNATIONAL SYMPOSIUM ON ACTIVE CONTROL OF SOUND AND VIBRATION, VOLS 1 & 2 LA English DT Proceedings Paper CT 1999 International Symposium on Active Control of Sound and Vibration (ACTIVE 99) CY DEC 02-04, 1999 CL FT LAUDERDALE, FL SP Inst Noise Control Engn USA ID NOISE; DUCT C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Griffin, S (reprint author), USAF, Res Lab, 3550 Aberdeen Rd, Kirtland AFB, NM 87117 USA. NR 17 TC 0 Z9 0 U1 1 U2 3 PU INST NOISE CONTROL ENGINEERING PI POUGHKEEPSIE PA PO BOX 3206, ARLINGTON BRANCH, POUGHKEEPSIE, NY 12603 USA BN 0-9622072-2-5 PY 1999 BP 1225 EP 1232 PG 4 WC Acoustics SC Acoustics GA BQ99G UT WOS:000165304400107 ER PT S AU Davis, ME Tomlinson, PG Maloney, RP AF Davis, ME Tomlinson, PG Maloney, RP GP IEEE IEEE TI Technical challenges in ultra-wideband radar development for target detection and terrain mapping SO PROCEEDINGS OF THE 1999 IEEE RADAR CONFERENCE: RADAR INTO THE NEXT MILLENNIUM SE Radar Conference LA English DT Proceedings Paper CT 1999 IEEE Radar Conference on Radar Into the Next Millennium CY APR 20-22, 1999 CL WALTHAM, MA SP IEEE Boston Sect, IEEE Aerospace & Electr Syst Soc AB This paper describes two Ultra-Wideband Synthetic Aperture Radars (SAR) currently being developed, One, the Foliage Penetration Advanced Technology Demonstration, will be installed on an Army C-12 and eventually the Global Hawk Unmanned Aerial Vehicle. It is designed to detect stationary military vehicles, which are camouflaged or hidden in forests and tree-lines. It employs a VHF SAR for screening and a UHF SAR for rejections of false-alarms. The second is an interferometric SAR for topographic terrain mapping. It operates on a business Set simultaneously with an X-band SAR, Together the two obtain high-quality imagery and terrain height of the ground even under foliage, The paper describes the phenomenology of foliage penetration, Ultra-Wideband SAR, and the different design issues associated with target detection and terrain mapping. C1 USAF, Res Lab, Rome, NY 13440 USA. RP Davis, ME (reprint author), USAF, Res Lab, Rome, NY 13440 USA. NR 10 TC 14 Z9 14 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4977-6 J9 RADAR CONF PY 1999 BP 1 EP 6 DI 10.1109/NRC.1999.767192 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BN39H UT WOS:000081778900001 ER PT S AU Williams, R Westerkamp, J Gross, D Palomino, A Fister, T AF Williams, R Westerkamp, J Gross, D Palomino, A Fister, T GP IEEE IEEE TI Automatic target recognition of time critical moving targets using 1D high range resolution (HRR) radar SO PROCEEDINGS OF THE 1999 IEEE RADAR CONFERENCE: RADAR INTO THE NEXT MILLENNIUM SE Radar Conference LA English DT Proceedings Paper CT 1999 IEEE Radar Conference on Radar Into the Next Millennium CY APR 20-22, 1999 CL WALTHAM, MA SP IEEE Boston Sect, IEEE Aerospace & Electr Syst Soc AB Synthetic Aperture Radar (SAR) imaging and Automatic Target Recognition (ATR) of moving targets pose a significant challenge due to the inherent difficulty of focusing moving targets. As a result, ATR of moving targets has recently received increased interest. High Range Resolution (HRR) radar mode offers an approach for recognizing moving targets by forming focused HRR profiles with significantly enhanced target-to-(clutter+noise) (T/(C+N)) via Doppler filtering and/or clutter cancellation. A goal of HRR ATR transition is the implementation and evaluation of algorithms exhibiting robustness under extended operating conditions (EOC). A subset of the Moving and Stationary Target Acquisition and Recognition (MSTAR) data set was used to study 1D template-based ATR development and performance. Due to the unavailability of a statistically significant moving ground target data set, this approach was taken as an interim step in assessing the separability of ground targets when using range only discriminants. This report summarizes the data and algorithm methodology, performance results, and recommendations. C1 USAF, Res Lab, SNAA, Wright Patterson AFB, OH 45433 USA. RP Williams, R (reprint author), USAF, Res Lab, SNAA, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 3 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4977-6 J9 RADAR CONF PY 1999 BP 54 EP 59 DI 10.1109/NRC.1999.767267 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BN39H UT WOS:000081778900011 ER PT S AU Brown, RD Lynch, ED Mokry, DW VanDamme, JM Schneible, RA Wicks, MC AF Brown, RD Lynch, ED Mokry, DW VanDamme, JM Schneible, RA Wicks, MC GP IEEE IEEE TI Near field focusing algorithm for high frequency ground penetration imaging radar SO PROCEEDINGS OF THE 1999 IEEE RADAR CONFERENCE: RADAR INTO THE NEXT MILLENNIUM SE Radar Conference LA English DT Proceedings Paper CT 1999 IEEE Radar Conference on Radar Into the Next Millennium CY APR 20-22, 1999 CL WALTHAM, MA SP IEEE Boston Sect, IEEE Aerospace & Electr Syst Soc AB Ground penetrating radar has been successfully used for imaging stratigraphic structures. The goal of our ground penetrating radar program is to provide a capability for strategic subsurface target detection for military applications. This paper describes an experimental approach to high frequency (HF) radar sub-surface profiling, and the results obtained from signal and data processing for deep tunnel detection. Ongoing experiments employ a bistatic radar system designed to detect buried objects located in the near-field of the HF sensor. Data analysis requires the use of synthetic aperture radar (SAR) processing to focus the image. Currently, experiments are conducted using surface contact antennas as part of a larger effort with an ultimate goal of collecting data via airborne sensors. The immediate goal of this effort is to determine the resolution achievable at depths commensurate with buried structures of strategic importance. This paper also examines the trade-off between frequency and propagation in an attempt to effect the best resolution possible. C1 USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, Rome, NY 13441 USA. RP Brown, RD (reprint author), USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, 26 Elect Pkwy, Rome, NY 13441 USA. NR 4 TC 4 Z9 4 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4977-6 J9 RADAR CONF PY 1999 BP 66 EP 71 DI 10.1109/NRC.1999.767273 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BN39H UT WOS:000081778900013 ER PT S AU Sanyal, PK Brown, RD Little, MO Schneible, RA Wicks, MC AF Sanyal, PK Brown, RD Little, MO Schneible, RA Wicks, MC GP IEEE IEEE TI Space-time adaptive processing bistatic airborne radar SO PROCEEDINGS OF THE 1999 IEEE RADAR CONFERENCE: RADAR INTO THE NEXT MILLENNIUM SE Radar Conference LA English DT Proceedings Paper CT 1999 IEEE Radar Conference on Radar Into the Next Millennium CY APR 20-22, 1999 CL WALTHAM, MA SP IEEE Boston Sect, IEEE Aerospace & Electr Syst Soc C1 USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, Rome, NY 13441 USA. RP Schneible, RA (reprint author), USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, 26 Elect Pkwy, Rome, NY 13441 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 SN 1097-5764 BN 0-7803-4977-6 J9 RADAR CONF PY 1999 BP 114 EP 118 DI 10.1109/NRC.1999.767286 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA BN39H UT WOS:000081778900022 ER PT S AU Antonik, P Wicks, MC AF Antonik, P Wicks, MC GP IEEE IEEE TI Integrated end-to-end radar processing using knowledge-based control SO PROCEEDINGS OF THE 1999 IEEE RADAR CONFERENCE: RADAR INTO THE NEXT MILLENNIUM SE Radar Conference LA English DT Proceedings Paper CT 1999 IEEE Radar Conference on Radar Into the Next Millennium CY APR 20-22, 1999 CL WALTHAM, MA SP IEEE Boston Sect, IEEE Aerospace & Electr Syst Soc AB An integrated approach to radar processing provides the best opportunity for maximum overall system performance. This is because the results of one stage may impact the processing in subsequent stages. Feedback from the various radar stages provides important information on how the data should be processed. This paper describes a concept for integrated end-to-end radar processing under knowledge-based control. Specific attention is paid to the formulation of rules, which may be procedural, heuristic, or hybrid combination. C1 USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, Rome, NY 13441 USA. RP Antonik, P (reprint author), USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, 26 Elect Pkwy, Rome, NY 13441 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 SN 1097-5764 BN 0-7803-4977-6 J9 RADAR CONF PY 1999 BP 256 EP 261 DI 10.1109/NRC.1999.767334 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BN39H UT WOS:000081778900050 ER PT S AU Adve, RS Hale, TB Wicks, MC AF Adve, RS Hale, TB Wicks, MC GP IEEE IEEE TI A two stage hybrid space-time adaptive processing algorithm SO PROCEEDINGS OF THE 1999 IEEE RADAR CONFERENCE: RADAR INTO THE NEXT MILLENNIUM SE Radar Conference LA English DT Proceedings Paper CT 1999 IEEE Radar Conference on Radar Into the Next Millennium CY APR 20-22, 1999 CL WALTHAM, MA SP IEEE Boston Sect, IEEE Aerospace & Electr Syst Soc AB This research presents two new Space-Time Adaptive Processing (STAP) algorithms; a two-dimensional non-statistical method and a hybridization of this approach with statistically based methods. The non-statistical algorithm developed here allows filtering of uncorrelated interference, such as discrete interferers, within the range cell of interest. However, performance of these algorithms in homogeneous correlated interference scenarios is inherently inferior to traditional statistical STAP algorithms. The proposed hybrid algorithm alleviates this drawback by implementing a second stage of statistical adaptive processing. This paper illustrates the advantages of using a two stage adaptive process to combine the direct data domain and statistical algorithms. The work presented in this paper brings together two different aspects of STAP research: statistical and direct data domain processing. In doing so, this research fulfills an important need in the context of practical STAP processing. C1 USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, Rome, NY 13440 USA. RP Adve, RS (reprint author), USAF, Res Lab, Sensors Directorate, Radar Signal Proc Branch, Rome, NY 13440 USA. NR 12 TC 8 Z9 10 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4977-6 J9 RADAR CONF PY 1999 BP 279 EP 284 DI 10.1109/NRC.1999.767344 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA BN39H UT WOS:000081778900054 ER PT S AU Berger, SD Welsh, BM AF Berger, SD Welsh, BM GP IEEE IEEE TI Dual channel matched filter system - A performance analysis SO PROCEEDINGS OF THE 1999 IEEE RADAR CONFERENCE: RADAR INTO THE NEXT MILLENNIUM SE Radar Conference LA English DT Proceedings Paper CT 1999 IEEE Radar Conference on Radar Into the Next Millennium CY APR 20-22, 1999 CL WALTHAM, MA SP IEEE Boston Sect, IEEE Aerospace & Electr Syst Soc AB In this paper, we analyze the signal-to-interference plus noise ratio (SINR) performance of a dual channel matched filter system under the assumption that the input interference plus noise signal for one channel is uncorrelated with the input signal for the other channel. We present an exact expression for the normalized SINR as a function of random variables with known distributions and then, using a Taylor series expansion, we present approximate expressions for the mean and variance of the normalized SINR. We note that under the assumption of uncorrelated inputs and known correlation matrices that the dual channel matched filter system is equivalent to a single channel matched filter designed to process both input signals. Further, we show that when estimated correlation matrices are used in place of the true correlation matrices the dual channel matched filter system achieves nearly the same normalized SINR performance as the single channel matched filter system with half the secondary data. These results suggest that, with the proper preprocessing to decorrelate the input signal, a single channel matched filter system can be replaced by a dual channel matched filter system of smaller size, leading to a reduction in computational cost and secondary data requirements. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Berger, SD (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1097-5764 BN 0-7803-4977-6 J9 RADAR CONF PY 1999 BP 295 EP 299 DI 10.1109/NRC.1999.767349 PG 5 WC Engineering, Electrical & Electronic SC Engineering GA BN39H UT WOS:000081778900057 ER PT S AU Redfield, RC AF Redfield, RC BE Granda, JJ Cellier, FE TI Bond graphs in dynamic systems design: Concepts for a continuously variable transmission SO PROCEEDINGS OF THE 1999 INTERNATIONAL CONFERENCE ON BOND GRAPH MODELING AND SIMULATION (ICBGM'99) SE SIMULATION SERIES LA English DT Proceedings Paper CT 4th International Conference on Bond Graph Modeling and Simulation (ICBGM 99) CY JAN 17-20, 1999 CL SAN FRANCISCO, CA SP Soc Comp Simulat Int DE bond graphs; dynamic systems; design AB Dynamic systems design requires configurations of component parts to provide specified relationships between dynamic variables. In the case of the continuously variable transmission (CVT) the input-output speed ratio is desired to be continuously variable between an upper and lower limit. Current design of the CVT requires such requirements as meticulously designed and manufactured belts and conical gear sets. Limits on power transmission and reliability are large concerns. Here, concepts for CVT's are developed to produce variable speed ratios where Bond Graphs are a key tool in generating specified dynamic relationships and in gaining insight into the design possibilities and limitations. Designs generated include a serial gyrator configuration and a mechanical filter design that behaves as a high pass filter. Loopic designs are also examined as they give increased freedom in selecting the performance of the dynamic configuration concepts. C1 USAF Acad, Dept Engn Mech, Colorado Springs, CO 80919 USA. RP Redfield, RC (reprint author), USAF Acad, Dept Engn Mech, Colorado Springs, CO 80919 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU SOC COMPUTER SIMULATION PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92177 USA SN 0735-9276 BN 1-56555-155-9 J9 SIMUL SERIES PY 1999 VL 31 IS 1 BP 225 EP 230 PG 4 WC Computer Science, Interdisciplinary Applications; Engineering, Multidisciplinary SC Computer Science; Engineering GA BP99X UT WOS:000086847200034 ER PT S AU Hunn, BP Camacho, MJ AF Hunn, BP Camacho, MJ GP HFES HFES TI Pilot performance and anxiety in a high-risk flight test environment SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc AB Recent flight testing of an Automatic Ground Collision Avoidance System (AutoGCAS) provided the opportunity to test a variety of variables thought to influence pilot and aircraft performance under high-risk flight situations. Pilot anxiety ratings were compared to measures of elevation from the ground, airspeed, time-to-ground impact, bank angle, and heart rate during the accomplishment of dive recovery maneuvers. Pilot activation of an experimental AutoGCAS provided the chance to study pilot anxiety levels in situations not normally encountered during flight test. A multivariate statistical model was used to determine the contribution of each of the variables chosen on the outcome of flying a semi-automated aircraft control system under high-risk conditions. Results indicated that several flight variables with high face validity were not major contributors in terms of determining pilot performance, however a more complex model of interactive system effects may be indicated by this test. C1 USAF, Flight Test Ctr, Edwards AFB, CA USA. RP Hunn, BP (reprint author), USAF, Flight Test Ctr, Edwards AFB, CA 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 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 26 EP 30 PG 5 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400006 ER PT S AU Ottati, WL Hickox, JC Richter, J AF Ottati, WL Hickox, JC Richter, J GP HFES HFES TI Eye scan patterns of experienced and novice pilots during visual flight rules (VFR) navigation SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc AB Electronic 3-D maps are becoming more widely accepted as replacements for traditional maps in the cockpit. As this transition occurs, we must determine how these electronic maps can be most effectively configured for performance and safety. Inherent in the technology available in electronic maps is the ability to customize display features. The challenge to human factors engineers is to design map controls and displays that optimize navigation performance. In this study we compared the eye scanning patterns on different terrain features between experienced and novice pilots during a visual flight rules (VFR) simulation. Implications for pilot training and suggestions for the design of electronic maps are made as a result of these findings. C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Ottati, WL (reprint author), USAF Acad, 2Lt, Colorado Springs, CO 80840 USA. NR 5 TC 4 Z9 5 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 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 66 EP 70 PG 5 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400014 ER PT S AU McMillan, G Calhoun, G Masquelier, BL Grigsby, SS Quill, LL Kancler, DE Revels, AR AF McMillan, G Calhoun, G Masquelier, BL Grigsby, SS Quill, LL Kancler, DE Revels, AR GP HFES HFES TI Comparison of hands-free versus conventional wearable computer control for maintenance applications SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc AB Past research on wearable computers for maintenance applications has focused on developing displays and presentation formats. This study emphasized wearable computer control technologies. Alternative control technologies were compared with standard and voice controls. Twelve subjects performed a synthetic maintenance task using three control device combinations for three different types of input. Time and error data were collected. The results show that for pointer movement, standard controls took significantly longer than voice. For discrete input, standard controls required significantly more time than voice and alternative controls. However, there were no significant time differences among controllers for text entry fill-in. Error results showed no significant differences. This research suggests that alternative and voice controls provide similar performance levels and both are superior to standard controls. In environments with changing noise spectra and noise levels such as a flight line, the alternative control suite provides hands-free control that complements voice without sacrificing performance. C1 USAF, Res Lab, HECP, Wright Patterson AFB, OH 45433 USA. RP McMillan, G (reprint author), USAF, Res Lab, HECP, 255 H St,Bldg 33, Wright Patterson AFB, OH 45433 USA. NR 11 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 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 1036 EP 1040 PG 5 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400199 ER PT S AU Wilson, GF Russell, C AF Wilson, GF Russell, C GP HFES HFES TI Operator functional state classification using neural networks with combined physiological and performance features SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc ID EEG AB Operator functional state assessment is a critical component of adaptive aiding systems. A combination of physiological and performance variables were used with a neural network to determine operator functional state. A multiple task battery provided three levels of mental workload. The data were randomly divided into two data sets, one was used to train a neural net and the other to test the accuracy of the trained neural net. The results showed an overall correct classification of 86.8% for the test data set. For the three levels of task difficulty the correct classification was 90.5% for low, 81.7% for the medium and 88.3% for the high. These results support the use of combined physiological and performance data to obtain high levels of operator functional state classification accuracy. The optimal approach to utilizing this information during system operation will have to be developed. With current technology the development of small, wearable operator state classifiers is possible. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Wilson, GF (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 5 TC 11 Z9 11 U1 0 U2 2 PU HUMAN FACTORS AND ERGONOMICS SOC PI SANTA MONICA PA PO BOX 1369, SANTA MONICA, CA 90406-1369 USA SN 1071-1813 BN 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 1099 EP 1102 PG 4 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400211 ER PT S AU Geiselman, EE AF Geiselman, EE GP HFES HFES TI Practical considerations for fixed wing helmet-mounted display symbology design SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc AB Helmet-mounted displays (HMDs) may become a primary source of head-up information in future tactical aircraft. In evaluations, HMDs have produced improved situation awareness and mission performance. To realize this improved performance, HMD equipped pilots spend significantly more time looking off-axis, away from traditional displays. Accordingly, it is important that HMD information be designed so targeting and ownship status symbology is effective and safe. The U. S. Air Force Research Laboratory is working to develop an optimized HMD symbology set. Toward this end, symbol designs must accommodate the conditions of intended use, technology limitations, and integration with other displays. This paper discusses efforts to design target tracking/location and ownship status symbologies for the day/night all weather fixed-wing tactical aircraft application. Design principles derived from both laboratory and flight test are presented. These principles relate to symbology frame of reference, orientation, compression, and line of sight mechanization. Evaluation methodologies are also discussed. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 10 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 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 1187 EP 1191 PG 5 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400227 ER PT S AU Nelson, WT Bolia, RS Ericson, MA McKinley, RL AF Nelson, WT Bolia, RS Ericson, MA McKinley, RL GP HFES HFES TI Spatial audio displays for speech communications: A comparison of free field and virtual acoustic environments SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc ID COCKTAIL-PARTY; LOCALIZATION AB The ability of listeners to detect, identify, and monitor multiple simultaneous speech signals was measured in free field and virtual acoustic environments. Factorial combinations of four variables, including audio condition, spatial condition, the number of speech signals, and the sex of the talker were employed using a within-subjects design. Participants were required to detect the presentation of a critical speech signal among a background of non-signal speech events. Results indicated that spatial separation increased the percentage of correctly identified critical speech signals as the number of competing messages increased. These outcomes are discussed in the context of designing binaural speech displays to enhance speech communication in aviation environments. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 18 TC 10 Z9 10 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 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 1202 EP 1205 PG 4 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400230 ER PT S AU Ericson, MA Bolia, RS Nelson, WT McKinley, RL AF Ericson, MA Bolia, RS Nelson, WT McKinley, RL GP HFES HFES TI Operational constraints on the utility of virtual audio cueing SO PROCEEDINGS OF THE HUMAN FACTORS AND ERGONOMICS SOCIETY 43RD ANNUAL MEETING, VOLS 1 AND 2 SE HUMAN FACTORS AND ERGONOMICS SOCIETY ANNUAL MEETING PROCEEDINGS LA English DT Proceedings Paper CT 43rd Annual Meeting of the Human-Factors-and-Ergonomics-Society CY SEP 27-OCT 01, 1999 CL HOUSTON, TX SP Human Factors & Ergon Soc ID SOUND LOCALIZATION; SPEECH AB The potential of virtual audio display technology to provide operators with veridical spatial cues may be substantially constrained by factors that are common in many operational settings - i.e., high noise level, limitations in the bandwidth of the audio source and/or display. The purpose of this study was to examine the effects of varying the bandwidth of a virtual sound source in the presence of broadband noise in a reverberant environment. Specifically, the signal-to-noise ratio (SNR) was varied from +50 dB to -10 dB, and the signal was low pass filtered at 1.6 kHz, 4 kHz, 8 kHz, and 15 kHz. Correlational analyses comparing actual and perceived sound source location revealed that both signal bandwidth and signal-to-noise ratio influenced auditory localization acuity, and that even under optimal bandwidth and noise conditions (15 kHz and +50 dB) localization in elevation was extremely poor. These findings have numerous implications for the design of spatial audio displays, especially those meant to be used in noisy environments. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Ericson, MA (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 13 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 0-945289-12-X J9 HUM FAC ERG SOC P PY 1999 BP 1206 EP 1209 PG 4 WC Computer Science, Cybernetics; Ergonomics; Telecommunications; Transportation Science & Technology SC Computer Science; Engineering; Telecommunications; Transportation GA BS93U UT WOS:000171438400231 ER PT J AU Sweeting, MN Lawrence, T Leduc, J AF Sweeting, MN Lawrence, T Leduc, J TI Low-cost orbit manoeuvres for minisatellites using novel resistojet thrusters SO PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING LA English DT Article DE minisatellites; resistojet thrusters; propulsion AB Electric propulsion using resistojets operating at low power (similar to 100 W) and using liquid propellants have re-emerged as attractive propulsion options for small satellites. Compared to low-power pulsed plasma thrusters (PPT), the resistojet achieves 50 times the increase in thrust (similar to 1-50 mN), which is necessary to overcome drag at solar maximum for small satellites in high drag obits (similar to 200 km). Two resistojet thrusters have been developed at the Surrey Space Centre (SSC), which utilize a packed bed of silicon carbide (SiC) particles for the heat exchanger. A thermodynamic model has been developed to study and optimize the thruster design and a series of practical performance tests with both nitrous oxide and water as propellants has been completed at the USAF Research Lab (Edwards AFB) using the NASA-JPL inverted pendulum thrust stand. Endurance tests (similar to 300 h duration) were conducted to determine possible lifetime limitations or failure modes. The results are very encouraging and resistojet thrusters are now proposed as options for future USAF and SSC minisatellite missions. This paper describes the complete resistojet system, test results for the USAF Mighty Sat II. I and its flight performance, its performance and integration on the UoSAT-12 minisatellite and its launch in April 1999 where this novel technique was demonstrated for the first time in low Earth orbit on 26 July 1999. C1 Univ Surrey, Surrey Space Ctr, Guildford GU2 5XH, Surrey, England. USAF, AFRL, Elect Propuls Lab, Edwards AFB, CA USA. RP Lawrence, T (reprint author), Univ Surrey, Surrey Space Ctr, Guildford GU2 5XH, Surrey, England. NR 4 TC 4 Z9 4 U1 0 U2 11 PU PROFESSIONAL ENGINEERING PUBLISHING LTD PI BURY ST EDMUNDS PA NORTHGATE AVENUE,, BURY ST EDMUNDS IP32 6BW, SUFFOLK, ENGLAND SN 0954-4100 J9 P I MECH ENG G-J AER JI Proc. Inst. Mech. Eng. Part G-J. Aerosp. Eng. PY 1999 VL 213 IS G4 BP 223 EP 231 DI 10.1243/0954410991532972 PG 9 WC Engineering, Aerospace; Engineering, Mechanical SC Engineering GA 253JJ UT WOS:000083553100004 ER PT B AU Stytz, MR Banks, SB AF Stytz, MR Banks, SB BE Chinni, MJ TI Requirements and HLA considerations for computer-generated actors in distributed mission training SO PROCEEDINGS OF THE MILITARY, GOVERNMENT AND AEROSPACE SIMULATION LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE intelligent agents; computer-generated actors; high-level architecture; system architecture; fidelity; reasoning systems; distributed mission training ID VIRTUAL ENVIRONMENTS AB Computer-generated actors are crucial to attaining a realistic, high fidelity and affordable distributed virtual environment for next generation aircrew training since they will generally be the opponents that the aircrews train against. However, many aspects of a computer-generated actors such as dynamics models, sensor models, command and control, and human decision making models for computer-generated actors are not accurate enough to support next generation uses. One fundamental but generally ignored source of error in the performance of computer-generated actors is the improper or incomplete portrayal of the human component. The objective of our paper is to argue the need for better computer-generated actors that employ improved human behavior models and to discuss the requirements that the next generation of computer generated actors and human behavior models must satisfy. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Stytz, MR (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 21 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 1-56555-168-0 PY 1999 BP 33 EP 38 PG 6 WC Engineering, Aerospace; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic SC Engineering; Computer Science GA BN23Y UT WOS:000081223500006 ER PT B AU Stytz, MR Banks, SB Engel, M Garrett, C Harrison, G Kerr, G AF Stytz, MR Banks, SB Engel, M Garrett, C Harrison, G Kerr, G BE Chinni, MJ TI Space weather for immersive virtual space environments SO PROCEEDINGS OF THE MILITARY, GOVERNMENT AND AEROSPACE SIMULATION LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE distributed training; virtual environments; space weather; ionospheric electron density; static charge build-up on spacecraft; parameterized atmospheric model; CAVE AB The Virtual SpacePlane (VSP) is a prototype of the Manned SpacePlane (MSP). To increase the realism of the space environment, we inserted a portrayal of space weather into the VSP's virtual environment and ported the VSP into the CAVE. In this paper we present background on the VSP project, space weather, the Cave Automatic Virtual Environment (CAVE), and describe the requirements and goals for the research. We discuss the design and implementation of the software that we used to insert space weather into the virtual environment, describe the changes that we made to the user interface, and the changes we made to port the VSP into the CAVE. The paper concludes with a presentation of our results and suggestions for future work. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45431 USA. RP Stytz, MR (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45431 USA. NR 16 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 1-56555-168-0 PY 1999 BP 88 EP 93 PG 6 WC Engineering, Aerospace; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic SC Engineering; Computer Science GA BN23Y UT WOS:000081223500015 ER PT B AU Peppler, P Spaulding, B AF Peppler, P Spaulding, B BE Chinni, MJ TI Low-cost, PC-based, DIS & HLA simulator visualization system SO PROCEEDINGS OF THE MILITARY, GOVERNMENT AND AEROSPACE SIMULATION LA English DT Proceedings Paper CT 1999 Advanced Simulation Technologies Conference (ASTC 99) CY APR 11-15, 1999 CL SAN DIEGO, CA SP Soc Comp Simulat Int DE DIS; HLA; simulator visualization; image generator; personal computers AB The mission of the Warfighter Training Research Division of the Air Force Research Laboratory is to take the lead in the research and development of training techniques for aircrews. A component of this research has been to evaluate the current state-of-the-art of hardware and software development for flight simulator design. As part of this effort, one goal is to reduce overall system costs. Requirements calling for more realistic environments have necessitated more sophisticated hardware. However, the cost and size of these image generators are still prohibitive for training systems that require multi-ship, multi-channel, full-field-of-view visual displays. If total costs can be reduced, more simulators can be purchased, facilitating team and mission training rather than just focusing on the development of individual pilot skills. However, this reduction in cost must not come at the expense of reduced simulator fidelity. This paper presents a snapshot of a Phase II Small Business Innovation Research (SBIR) project which focuses on developing a low-cost, high-fidelity simulator visualization system by combining the current state-of-the-art of PC-based image generators (IGs) with a portable, HLA- and DIS-compatible software infrastructure developed by MaK. As part of this goal to reduce costs, Commercial-Off-The-Shelf (COTS) products were used where appropriate. The system design was driven by the recognition that current DIS or HLA stealth applications provide many of the capabilities for displaying out-the-window graphics required for simulator visuals. Reuse of stealth components reduces development costs and allows for portability across a wide range of hardware IG platforms. Finally, by defining a reconfigurable environment, the visualization system could be used to support a wide range of applications including physical and virtual simulators. Figure 1 provides a preview of capabilities of the system presented in this paper. C1 USAF, Res Lab, Warfighter Training Res Div, Mesa, AZ 85206 USA. RP Peppler, P (reprint author), USAF, Res Lab, Warfighter Training Res Div, Mesa, AZ 85206 USA. NR 1 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 1-56555-168-0 PY 1999 BP 175 EP 180 PG 6 WC Engineering, Aerospace; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic SC Engineering; Computer Science GA BN23Y UT WOS:000081223500029 ER PT B AU Karna, SP Pineda, AC Shedd, WM Singaraju, BK AF Karna, SP Pineda, AC Shedd, WM Singaraju, BK BE Hemment, PLF TI Electronic structure studies of the E '(delta) and the triplet centers in alpha-SiO2 SO PROCEEDINGS OF THE NINTH INTERNATIONAL SYMPOSIUM ON SILICON-ON-INSULATOR TECHNOLOGY AND DEVICES SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 9th International Symposium on Silicon-on-Insulator Technology and Devices, at the 195th Meeting of the Electrochemical-Society CY MAY 02-07, 1999 CL SEATTLE, WA SP Electrochem Soc, Electr Div ID AMORPHOUS SIO2; DEFECT CENTERS; BURIED SIO2; E' CENTERS; STATE; INTERFACE; GENERATION; TRAPS AB Ab initio Hartree-Fock calculations have been performed on the electronic structure and spin properties of model clusters representing E's and triplet-state centers observed in amorphous SiO2 (a-SiO2). The calculated results strongly suggest that E'(delta) centers involve a trapped hole, shared between two Si atoms adjacent to a mono-oxygen vacancy in a silicon dioxide network The calculated spin properties of the assumed models for the triplet-state center are too large in comparison with experiment. It is suggested that the two-Si atom mono-oxygen vacancy structure can not be responsible for the 134 G triplet splitting observed along with the E'(delta) center. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Karna, SP (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE,Bldg 914, Kirtland AFB, NM 87117 USA. NR 26 TC 8 Z9 8 U1 0 U2 0 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-225-7 J9 ELEC SOC S PY 1999 VL 99 IS 3 BP 161 EP 166 PG 6 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Materials Science, Characterization & Testing; Physics, Applied; Physics, Condensed Matter SC Electrochemistry; Engineering; Materials Science; Physics GA BM89N UT WOS:000080052300021 ER PT B AU LeVan, PD Brown, KW Singh, A AF LeVan, PD Brown, KW Singh, A BE Li, SS Liu, HC Tidrow, MZ Gunapala, SD TI Multi-waveband infrared focal plane arrays - Recent trends for lower-background operations SO PROCEEDINGS OF THE SIXTH INTERNATIONAL SYMPOSIUM ON LONG WAVELENGTH INFRARED DETECTORS AND ARRAYS: PHYSICS AND APPLICATIONS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 6th International Symposium on Long Wavelength Infrared Detectors and Arrays - Physics and Applications, at the Fall Meeting of the Electrochemical-Society CY NOV 05-06, 1998 CL BOSTON, MA SP Electrochem Soc AB The past several years have witnessed sizable investments by the Ballistic Missile Defense Organization, the Air Force and the Navy in dualband infrared focal plane array technology. Both quantum well photodetector and HgCdTe photovoltaic approaches have been taken along these lines. The fruits of these investments should be realized In the near-term in the form of focal plane arrays that approach levels of performance and maturity sufficiently high to meet a wide variety of system and user needs. We provide an overview of the current status in multi-waveband infrared focal plane arrays. We also present several interesting operational concepts for these detectors. Finally, we conclude with speculation on future developments in this area. C1 USAF, VSSS, Res Lab, Kirtland AFB, NM 87117 USA. RP LeVan, PD (reprint author), USAF, VSSS, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 5 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 1-56677-215-X J9 ELEC SOC S PY 1999 VL 98 IS 21 BP 12 EP 28 PG 17 WC Electrochemistry; Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Applied SC Electrochemistry; Engineering; Instruments & Instrumentation; Physics GA BM81T UT WOS:000079832100002 ER PT B AU Szmulowicz, F Liu, HC Brown, GJ Wasilewski, ZR Buchanan, M AF Szmulowicz, F Liu, HC Brown, GJ Wasilewski, ZR Buchanan, M BE Li, SS Liu, HC Tidrow, MZ Gunapala, SD TI Toward the design of optimized GaAs/AlGaAs p-type multiple-quantum wells for infrared detection at normal incidence: Model and experiment SO PROCEEDINGS OF THE SIXTH INTERNATIONAL SYMPOSIUM ON LONG WAVELENGTH INFRARED DETECTORS AND ARRAYS: PHYSICS AND APPLICATIONS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 6th International Symposium on Long Wavelength Infrared Detectors and Arrays - Physics and Applications, at the Fall Meeting of the Electrochemical-Society CY NOV 05-06, 1998 CL BOSTON, MA SP Electrochem Soc ID PHOTORESPONSE MEASUREMENT; ABSORPTION; PHOTODETECTORS AB The photoresponse of long-wavelength and mid-wavelength infrared p-QWIPs is investigated systematically as a function of well width, alloy concentration, polarization, and temperature. The responsivity and the dark current characteristics are also measured. The electronic structure and wave functions of the quantum wells are calculated using the 8x8 envelope-function model (EFA). Optimum designs were shown to correspond to structures with the LH2 (second light hole) state at the top of the well. The bound-to-continuum absorption curves were then calculated on an absolute scale as a function of photon energy, light polarization, and temperature. Using these theoretical designs, a number of LWIR and MWIR QWIP structures were grown by MBE and their characteristics measured and compared to theory. Four sets of p-type GaAs/AlGaAs QWIPs were grown to test the theory, comprising LWIR and MWIR p-QWIPS with different widths and alloy concentrations. Good experimental-theoretical agreement is found for the long-wavelength threshold, shape, polarization, and temperature dependence of the photoresponse. The calculated energy levels and Fermi energy are consistent with experiments. A complete optimization of the p-type QWIP awaits additional transport studies as well as response studies as a function of barrier width, doping concentration, and the number of quantum wells. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Szmulowicz, F (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 14 TC 0 Z9 0 U1 0 U2 1 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-215-X J9 ELEC SOC S PY 1999 VL 98 IS 21 BP 145 EP 157 PG 13 WC Electrochemistry; Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Applied SC Electrochemistry; Engineering; Instruments & Instrumentation; Physics GA BM81T UT WOS:000079832100012 ER PT B AU Brown, GJ Szmulowicz, F Lin, CH Linville, R Mahalingam, K Saxler, A Ahoujja, MA AF Brown, GJ Szmulowicz, F Lin, CH Linville, R Mahalingam, K Saxler, A Ahoujja, MA BE Li, SS Liu, HC Tidrow, MZ Gunapala, SD TI Characterization and modeling of InAs/InGaSb type II superlattices for infrared detection at long and very long wavelengths SO PROCEEDINGS OF THE SIXTH INTERNATIONAL SYMPOSIUM ON LONG WAVELENGTH INFRARED DETECTORS AND ARRAYS: PHYSICS AND APPLICATIONS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 6th International Symposium on Long Wavelength Infrared Detectors and Arrays - Physics and Applications, at the Fall Meeting of the Electrochemical-Society CY NOV 05-06, 1998 CL BOSTON, MA SP Electrochem Soc ID ENVELOPE-FUNCTION APPROXIMATION; INAS/INXGA1-XSB SUPERLATTICES; GENERAL EXPRESSION; SECULAR EQUATION; QUANTUM-WELLS AB We report on the growth and characterization of InAs/InxGa1-xSb strained-layer superlattices (SLS) designed with photoresponse cut-off wavelengths of 5 mu m, 10 mu m and 13 mu m. The structural parameters, layer thicknesses and compositions, were chosen to optimize the infrared absorption while maintaining a strain balance and lattice match with the (001) GaSb substrate. 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 InAs and In0.23Ga0.77Sb lattice-matched to the GaSb substrates. This set of superlattice materials was characterized using x-ray diffraction, cross-sectional TEM, photoresponse and Half measurements. The measured photoresponse cut-off energies were in good agreement with the predicted energy band gap for each of the superlattices as designed. The photoresponse spectra show a sharp transition energy at the band edge indicating the high quality and repeatability of the superlattice layer thicknesses and interfaces. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Brown, GJ (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 19 TC 0 Z9 0 U1 0 U2 2 PU ELECTROCHEMICAL SOCIETY INC PI PENNINGTON PA 65 S MAIN ST, PENNINGTON, NJ 08534-2839 USA BN 1-56677-215-X J9 ELEC SOC S PY 1999 VL 98 IS 21 BP 177 EP 187 PG 11 WC Electrochemistry; Engineering, Electrical & Electronic; Instruments & Instrumentation; Physics, Applied SC Electrochemistry; Engineering; Instruments & Instrumentation; Physics GA BM81T UT WOS:000079832100015 ER PT B AU Chamillard, AT Karolick, D AF Chamillard, AT Karolick, D BE Joyce, D TI Using learning style data in an introductory computer science course SO PROCEEDINGS OF THE THIRTIETH SIGCSE TECHNICAL SYMPOSIUM ON COMPUTER SCIENCE EDUCATION LA English DT Proceedings Paper CT 30th SIGCSE Technical Symposium on Computer Science Education CY MAR 24-28, 1999 CL NEW ORLEANS, LA SP Assoc Computing Machinery, Special Interest Grp Comp Sci Educ AB Because learning styles affect how students approach new material, a deeper comprehension of these styles san help professors enhance student learning experiences. in this paper we discuss how learning style data can be used to help guide student study habits and instructional strategies. Additionally, we examine whether or not there is a correlation between learning style and academic performance in an introductory computer science course. C1 USAF Acad, Dept Comp Sci, Colorado Springs, CO 80840 USA. RP Chamillard, AT (reprint author), USAF Acad, Dept Comp Sci, Colorado Springs, CO 80840 USA. NR 6 TC 6 Z9 6 U1 0 U2 0 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036-9998 USA BN 1-58113-085-6 PY 1999 BP 291 EP 295 DI 10.1145/299649.299790 PG 5 WC Computer Science, Interdisciplinary Applications; Education, Scientific Disciplines SC Computer Science; Education & Educational Research GA BM73Q UT WOS:000079628300062 ER PT B AU Nicholas, T Maxwell, DC AF Nicholas, T Maxwell, DC BE Ellyin, F Provan, JW TI Evolution and effects of damage in Ti-6Al-4V under high cycle fatigue SO PROGRESS IN MECHANICAL BEHAVIOUR OF MATERIALS (ICM8), VOL 3: ADVANCE MATERIALS AND MODELLING OF MECHANICAL BEHAVIOUR LA English DT Proceedings Paper CT 8th International Conference on the Mechanical Behaviour of Materials (ICM8) CY MAY 16-21, 1999 CL VICTORIA CONF CTR, VICTORIA, CANADA SP ICM Board Governors HO VICTORIA CONF CTR C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Nicholas, T (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU UNIV VICTORIA, DEPT MECH ENGN PI VICTORIA PA VICTORIA, BC V8W 3P6, CANADA BN 1-55058-165-1 PY 1999 BP 1161 EP 1166 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary; Mechanics; Metallurgy & Metallurgical Engineering SC Engineering; Materials Science; Mechanics; Metallurgy & Metallurgical Engineering GA BQ77F UT WOS:000089495600062 ER PT S AU Daniels, R AF Daniels, R BE Wu, MH TI Realizing the increased potential of an open system high definition digital projector design SO PROJECTION DISPLAYS V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Projection Displays V CY JAN 26-28, 1999 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, Soc Photo Opt Instrumentat Engineers DE electronic displays; display projector; Common Large Area Display Set (CLADS); Head up Display (HUD); head down display; direct view display; space plane; direct view head down instrument panel; synthetic vision large area display projection displays; solid state laser projector and helmet mounted cueing for displays AB Modern video projectors are becoming more compact and capable. Various display technologies are very competitive and are delivering higher performance and more compact projectors to market at an ever quickening pace. However the end users are often left with the daunting task of integrating the "off the self projectors" into a previously existing system. As the projectors become more digitally enhanced, there will be a series of designs, as the digital projector technology matures. The design solutions will be restricted by the state of the art at the time of manufacturing. In order to allow the most growth and performance for a given price, many design decisions will be made and revisited over a period of years or decades. A modular open digital system design concept is indeed a major challenge of the future high definition digital displays for all applications. C1 USAF, Res Lab, Visual Display Syst Branch, Wright Patterson AFB, OH 45433 USA. RP Daniels, R (reprint author), USAF, Res Lab, Visual Display Syst Branch, 2255 H St,Bldg 248,Rm 300, Wright Patterson AFB, OH 45433 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3105-2 J9 P SOC PHOTO-OPT INS PY 1999 VL 3634 BP 171 EP 179 DI 10.1117/12.349352 PG 9 WC Optics; Imaging Science & Photographic Technology SC Optics; Imaging Science & Photographic Technology GA BN13Y UT WOS:000080851800017 ER PT S AU Ryan, PT Lowrey, WH De La Rue, IA Fugate, RQ AF Ryan, PT Lowrey, WH De La Rue, IA Fugate, RQ BE Roggemann, MC Bissonnette, LR TI Scintillation characterization for multiple beams SO PROPAGATION AND IMAGING THROUGH THE ATMOSPHERE III 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 III CY JUL 22-23, 1999 CL DENVER, CO SP SPIE, Remote Sensing Soc DE atmospheric turbulence; scintillation AB The Starfire Optical Range (SOR) has measured atmospheric scintillation on 1.06 micron laser beams propagated from the ground to retroreflectors on satellites and back to the ground. The primary purpose of this experiment was to examine upward scintillation on laser beams, especially the results of varying the number of beams and their diameters. Separating the energy into beams that sample different portions of the atmosphere reduces the scintillation if the atmospheric turbulence each traverses is independent. How much the beam diameter affects scintillation is determined by diffraction and the size of the Fried parameter. If the beam is smaller than r(0), the beam remains largely intact but moves around. If the beam is much larger than r(0), the far field pattern consists of many speckles. The circular beam diameters were varied from 6 to 12 to 19 cm using a telescopic design. These diameters were chosen to be approximately 0.5, 1.0 and 1.5 times typical ro values. The number of mutually incoherent beams was 1, 2 or 4. These were pointed at the satellites using tracking of reflected sunlight. Laser light was collected with a 3.5m telescope with its pupil divided into four equal areas. The pupil was then re-imaged onto four InGaAs photodiodes operating at 10 kHz. Dividing the pupil allowed separation of the fluctuation sources. Upward scintillation has no aperture averaging at the satellite and appears simultaneously and identically in each subaperture at the 3.5m. Downward scintillation is small due to aperture averaging and is nearly independent for each of the subapertures. For satellites with arrays of corner cubes, a third source of fluctuations is the interference pattern of the array sweeping past the collecting telescope. These fluctuations have the same depth in each subaperture but they have a small phase delay. Experimental results show that increasing the number of beams does reduce the amount of fluctuations as predicted. Atmospheric dependence results were mixed. The amount of scintillation increased with decreasing theta(0); however no clear dependence on r(0) was seen. Measuring r(0) at a different location than the beam projector may be the reason. The cumulative probabilities of the fluctuations are close to being log normal for both single and multiple beams. C1 USAF, Res Lab, Starfire Opt Range, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Ryan, PT (reprint author), USAF, Res Lab, Starfire Opt Range, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 9 TC 8 Z9 8 U1 1 U2 5 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3249-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3763 BP 210 EP 217 DI 10.1117/12.363615 PG 8 WC Remote Sensing; Optics SC Remote Sensing; Optics GA BN95F UT WOS:000083637500021 ER PT S AU Yepez, J AF Yepez, J BE Williams, CP TI Quantum computation of fluid dynamics SO QUANTUM COMPUTING AND QUANTUM COMMUNICATIONS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 1st NASA International Conference on Quantum Computing and Quantum Communications (QCQC 98) CY FEB 17-20, 1998 CL PALM SPRINGS, CALIFORNIA SP NASA, Joint Propuls Lab, Ctr Integrated Space Microsyst, Ballist Missle Def Org, NASA, Joint Propuls Lab, Ctr Space Microelectr Technol, NASA, Auton & Informat Technol ID EQUATION AB Presented is a quantum lattice gas for Navier-Stokes fluid dynamics simulation. The quantum lattice-gas transport equation at the microscopic scale is presented as a generalization of the classical lattice-gas transport equation. A special type of quantum computer network is proposed that is suitable for implementing the quantum lattice gas. The quantum computer network undergoes a partial collapse of the wavefunction at every time step of the dynamical evolution. Each quantum computer in the network comprises only a few qubits, which are entangled for only a short time period. A Chapman-Enskog type analysis of the quantum computer network indicates that the total system of qubits behaves exactly like a viscous lattice-gas fluid at the macroscopic scale. Because of the quantum mechanical nature of the scattering process, superposition of outgoing collisional possibilities occurs. The quantum lattice gas obeys detail balance in its collisions and is therefore an unconditionally stable algorithm for fluid dynamics simulation. C1 USAF, Res Lab, Hanscom Field, MA 01731 USA. RP Yepez, J (reprint author), USAF, Res Lab, Hanscom Field, MA 01731 USA. NR 22 TC 8 Z9 8 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-65514-X J9 LECT NOTES COMPUT SC PY 1999 VL 1509 BP 34 EP 60 PG 27 WC Computer Science, Theory & Methods SC Computer Science GA BP13A UT WOS:000084208300003 ER PT S AU Bowden, CM Dowling, JP Hotaling, SP AF Bowden, CM Dowling, JP Hotaling, SP BE Williams, CP TI Quantum computing using Electron-Nuclear Double Resonances SO QUANTUM COMPUTING AND QUANTUM COMMUNICATIONS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 1st NASA International Conference on Quantum Computing and Quantum Communications (QCQC 98) CY FEB 17-20, 1998 CL PALM SPRINGS, CALIFORNIA SP NASA, Joint Propuls Lab, Ctr Integrated Space Microsyst, Ballist Missle Def Org, NASA, Joint Propuls Lab, Ctr Space Microelectr Technol, NASA, Auton & Informat Technol ID EARTH FLUORO-HALIDES; F-CENTERS; LOGIC AB We consider the use of Electron-Nuclear Double Resonance (ENDOR) techniques in quantum computing. ENDOR resolution as a possible limiting factor is discussed. It is found that ENDOR and double-ENDOR techniques have sufficient resolution for quantum computing applications. C1 USA, Missile Command, Weapons Sci Directorate, AMSMI RD WS ST,Missile Res Dev & Engn Ctr, Redstone Arsenal, AL 35898 USA. USAF, Rome Lab, Rome, NY 13441 USA. RP Bowden, CM (reprint author), USA, Missile Command, Weapons Sci Directorate, AMSMI RD WS ST,Missile Res Dev & Engn Ctr, Redstone Arsenal, AL 35898 USA. RI DOWLING, JONATHAN/L-2749-2013 NR 20 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 3-540-65514-X J9 LECT NOTES COMPUT SC PY 1999 VL 1509 BP 364 EP 372 PG 9 WC Computer Science, Theory & Methods SC Computer Science GA BP13A UT WOS:000084208300033 ER PT S AU Maher, J Zhang, YH Wang, H AF Maher, J Zhang, YH Wang, H BE Trebits, R Kurtz, JL TI Space-time adaptive processing with sum and multiple difference beams for airborne radars SO RADAR SENSOR TECHNOLOGY IV SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Radar Sensor Technology IV CY APR 08, 1999 CL ORLANDO, FL SP SPIE DE radar; signal processing; adaptive processing AB This paper describes some new results on a signal processing approach for airborne surveillance radars. This is a spacetime adaptive processing (STAP) technique that simultaneously processes temporal data from sum and difference (Sigma Delta) beams to suppress clutter returns. The approach also includes employing spatial adaptive pre-suppression (SAPS) to suppress wideband noise jammers in a two-stage processor. Previous work on Sigma Delta-STAP with SAPS has concentrated on the case with one difference beam. This has shown to be effective in suppressing strong clutter and jamming when the number of wideband noise jammers does not exceed the number of auxiliary channels used for SAPS. Additional difference beams, which are orthogonal to these two beams and to each other, can be available on most radar systems. This work analyzes the performance of the Sigma Delta-STAP with SAPS processor, which utilizes these additional difference beams. It is shown to be effective with either one or two additional beams when the number of jammers exceeds the number of auxiliary channels by one. This occurs even though the jammers are in the nulls of the additional beams. Additional results show that the performance can improve when the jammers move from the nulls and that the clutter entering through the auxiliary has little impact. C1 USAF, Res Lab, AFRL, SNRD, Rome, NY 13441 USA. RP USAF, Res Lab, AFRL, SNRD, Rome, NY 13441 USA. EM maherj@rl.af.mil NR 17 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3178-8 J9 PROC SPIE PY 1999 VL 3704 BP 160 EP 169 DI 10.1117/12.354593 PG 10 WC Engineering, Electrical & Electronic SC Engineering GA BN68U UT WOS:000082587000017 ER PT J AU Smirniotopoulos, JG Lonergan, GJ Abbott, RM Choyke, PL Czum, JM Dalrymple, NC DoDai, D Feigin, DS Ho, VB Leyendecker, JR Rovira, MJ AF Smirniotopoulos, JG Lonergan, GJ Abbott, RM Choyke, PL Czum, JM Dalrymple, NC DoDai, D Feigin, DS Ho, VB Leyendecker, JR Rovira, MJ TI Image interpretation session: 1998 SO RADIOGRAPHICS LA English DT Editorial Material DE arteriovenous malformations, pulmonary; emphysema, pulmonary; histiocytosis; melanoma; neurofibromatosis; sarcoidosis; sclerosis, tuberous; temporal bone, neoplasms; thymus, cysts; von Hippel-Landau disease ID LANGERHANS CELL HISTIOCYTOSIS; VONHIPPEL-LINDAU DISEASE; SWYER-JAMES SYNDROME; RADIOLOGIC-PATHOLOGICAL CORRELATION; THYROGLOSSAL DUCT CARCINOMA; ENDOLYMPHATIC SAC TUMORS; T1-WEIGHTED MR-IMAGES; TUBEROUS SCLEROSIS; CT FINDINGS; GASTROINTESTINAL SARCOIDOSIS C1 Uniformed Serv Univ Hlth Sci, Dept Radiol, Bethesda, MD 20814 USA. Armed Forces Inst Pathol, Dept Radiol, Washington, DC 20306 USA. Wilford Hall USAF Med Ctr, Dept Radiol, San Antonio, TX 78236 USA. NIH, Dept Radiol, Bethesda, MD 20892 USA. Henry M Jackson Fdn Advancement Mil Med, Dept Radiol, Bethesda, MD USA. Tripler Army Med Ctr, Dept Radiol, Honolulu, HI 96859 USA. Madigan Army Med Ctr, Tacoma, WA 98431 USA. RP Smirniotopoulos, JG (reprint author), Uniformed Serv Univ Hlth Sci, Dept Radiol, Bethesda, MD 20814 USA. RI Smirniotopoulos, James/D-3726-2011 NR 77 TC 5 Z9 5 U1 0 U2 0 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 USA SN 0271-5333 J9 RADIOGRAPHICS JI Radiographics PD JAN-FEB PY 1999 VL 19 IS 1 BP 205 EP 233 PG 29 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 158GB UT WOS:000078106700017 PM 10939917 ER PT S AU Wood, BE Green, BD Uy, OM Cain, RP Thorpe, J AF Wood, BE Green, BD Uy, OM Cain, RP Thorpe, J BE Chen, PTC Gu, ZH Maradudin, AA TI Satellite contamination and materials outgassing effects databases SO ROUGH SURFACE SCATTERING AND CONTAMINATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Rough Surface Scattering and Contamination CY JUL 21-23, 1999 CL DENVER, CO SP SPIE DE cryogenics; spacecraft; quartz crystal microbalance; QCM; TQCM; CQCM; MSX; satellite; telescope; contamination AB This paper describes a program for consolidating data from quartz crystal microbalances (QCMs) that will enable one to rapidly locate previous measurements on specific materials and data from past space flight experiments. When complete, the databases will contain information on materials outgassing obtained using the ASTM-E-1559 standard, and flight observations of mass accumulations. Once established, these databases will be available to the entire community and will provide a valuable source of material outgassing information. The data should be useful to those working in the Contamination area for mission design and materials specification. Data are being accumulated from both national and international sources. The space flight database will include data from past NASA missions, as well as DOD (including the BMDO-sponsored Mid-course Space Experiment (MSX) program), Canadian Space Agency, European Space Agency, Russian MIR space station, and eventually, the International Space Station. A website is being generated which will be the vehicle for storing the data that are accumulated. Once completed the databases will be managed by the NASA/Space and Environmental Effects (SEE) Program Office at the Marshall Space Flight Center in Huntsville, Alabama. 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 8 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3270-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3784 BP 16 EP 23 DI 10.1117/12.366696 PG 8 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BN98A UT WOS:000083742000002 ER PT J AU Frazier, JM Pachter, R Trohalaki, S Geiss, KT AF Frazier, JM Pachter, R Trohalaki, S Geiss, KT TI Computational methods in toxicology - April 20-22, 1998, Dayton, OH, USA - Preface SO SAR AND QSAR IN ENVIRONMENTAL RESEARCH LA English DT Editorial Material C1 USAF, Res Lab, Operat Toxicol Branch, AFRL,HEST, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Laser Hardened Mat Branch, AFRL,MLPJ, Wright Patterson AFB, OH 45433 USA. Major Shared Resource Ctr High Performance Comp, ASC, MSRC, Wright Patterson AFB, OH USA. Ohio Supercomp Ctr, Columbus, OH USA. RP Frazier, JM (reprint author), USAF, Res Lab, Operat Toxicol Branch, AFRL,HEST, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 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 1062-936X J9 SAR QSAR ENVIRON RES JI SAR QSAR Environ. Res. PY 1999 VL 10 IS 2-3 BP I EP V PG 5 WC Chemistry, Multidisciplinary; Computer Science, Interdisciplinary Applications; Environmental Sciences; Mathematical & Computational Biology; Toxicology SC Chemistry; Computer Science; Environmental Sciences & Ecology; Mathematical & Computational Biology; Toxicology GA 234JY UT WOS:000082482000001 ER PT S AU Vaughan, WW Owens, JK Niehuss, KO Shea, MA AF Vaughan, WW Owens, JK Niehuss, KO Shea, MA BE Dow, JM Beutler, G TI The NASA Marshall solar activity model for use in predicting satellite lifetime SO SATELLITE DYNAMICS, ORBIT ANALYSIS AND COMBINATION OF SPACE TECHNIQUES SE ADVANCES IN SPACE RESEARCH-SERIES LA English DT Article; Proceedings Paper CT PSD1 Symposium of COSPAR Technical Panel on Satellite Dynamics at the 32nd COSPAR Scientific Assembly CY JUL 12-19, 1998 CL NAGOYA, JAPAN SP European Space Agcy, Inst Space & Astronaut Sci, Int Union Geodesy & Geophys, Int Assoc Geodesy, Natl Space Agcy Japan, Comm Space Res AB A principal source of uncertainty in estimating future orbital altitude densities for predicting satellite orbital lifetimes is the solar extreme ultraviolet (EUV) heat input values to use in the atmospheric model. The observed 10.7-cm solar radio flux (not adjusted to 1 AU) is used as a proxy for this most significant input, which is not otherwise available. A statistical technique was developed to estimate the future 13-month Zurich smoothed solar radio flux and geomagnetic index values. A principal application of this model is as an input to thermospheric density models used for satellite lifetime predictions. (C) 1999 COSPAR. Published by Elsevier Science Ltd. C1 Univ Alabama, Huntsville, AL 35899 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. USAF, Res Lab, Bedford, MA 01731 USA. RP Vaughan, WW (reprint author), Univ Alabama, Huntsville, AL 35899 USA. NR 13 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON PRESS LTD PI OXFORD PA THE BOULEVARD LANGFORD LANE KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0273-1177 J9 ADV SPACE RES-SERIES PY 1999 VL 23 IS 4 BP 715 EP 719 DI 10.1016/S0273-1177(99)00140-4 PG 5 WC Engineering, Aerospace; Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences; Remote Sensing SC Engineering; Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences; Remote Sensing GA BN17G UT WOS:000080929200012 ER PT J AU Boinard, P Boinard, E Pethrick, RA Banks, WM Crane, RL AF Boinard, P Boinard, E Pethrick, RA Banks, WM Crane, RL TI Dielectric spectroscopy as a non-destructive technique to assess water sorption in composite materials SO SCIENCE AND ENGINEERING OF COMPOSITE MATERIALS LA English DT Article ID THERMOSETS AB Over the last ten years, the application of high frequency dielectric spectroscopy techniques for the assessment of composite structures has been investigated. Novel approaches to assess non-destructively the evolution during ageing of adhesively bonded carbon fibre reinforced plastic (CFRP) structures and bulk glass fibre reinforced plastic (GRP) structures are presented in this paper and the results are critically assessed. The applicability and limitations of dielectric measurements, in both frequency and time domain, to the monitoring of water ingress at 30 degrees C and 60 degrees C are examined. The correlation between gravimetric and high frequency dielectric spectroscopy data demonstrates the suitability of the techniques regarding the assessment of water uptake in composites structures and illustrates its potential as a non-destructive evaluation (NDE) technique. The dielectric time domain response (TDR) study of adhesively bonded structures indicates a new way to assess such structures. The approach for frequency domain analysis of bulk GRP using a coaxial probe technique indicates the potential portability of the technique for in-situ measurements. C1 Univ Strathclyde, Dept Pure & Appl Chem, Glasgow G1 1XL, Lanark, Scotland. Univ Strathclyde, Dept Mech Engn, Glasgow G1 1XJ, Lanark, Scotland. USAF, Non Destruct Evaluat Branch, Mat Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Boinard, P (reprint author), Univ Strathclyde, Dept Pure & Appl Chem, Thomas Graham Bldg,295 Cathedral St, Glasgow G1 1XL, Lanark, Scotland. NR 8 TC 5 Z9 5 U1 3 U2 7 PU FREUND PUBLISHING HOUSE LTD PI LONDON PA STE 500, CHESHAM HOUSE, 150 REGENT ST, LONDON W1R 5FA, ENGLAND SN 0334-181X J9 SCI ENG COMPOS MATER JI Sci. Eng. Compos. Mater. PY 1999 VL 8 IS 4 BP 175 EP 179 PG 5 WC Materials Science, Composites SC Materials Science GA 342EM UT WOS:000088632300001 ER PT B AU Schumacher, CJ Yeh, HH Banda, S AF Schumacher, CJ Yeh, HH Banda, S BE Sivasundaram, S TI Dynamic inversion and feedback linearization for missile autopilot design SO SECOND INTERNATIONAL CONFERENCE ON NONLINEAR PROBLEMS IN AVIATION & AEROSPACE VOL 1 AND 2 LA English DT Proceedings Paper CT 2nd International Conference on Nonlinear Problems in Aviation and Aerospace CY APR 29-MAY 01, 1998 CL EMBRY RIDDLE AERONAUT UNIV, DAYTONA BEACH, FL SP Int Fed Nonlinear Analysts, Int Fed Informat Proc, Inst Elect & Electr Engineers Inc, Apollo Aerosp Int Inc, Embry Riddle Aeronaut Univ HO EMBRY RIDDLE AERONAUT UNIV AB In the flight control community, feedback linearization has found widespread applications, and is better known by a different name: dynamic inversion. From a mathematical standpoint, one may say that dynamic inversion is a special case of feedback linearization where all elements of the relative degree vector are zero. This paper discusses the differences betweeen feedback linearization and dynamic inversion, and compares these two designs on a bank-to-turn air-to-air missile autopilot system. Both designs are based on the six degree-of-freedom rigid body nonlinear dynamics of the missile. Performance analysis is conducted on a complete simulation model with detailed aerodynamic data. The dynamic inversion approach is easier to implement and is more robust, but the feedback linearization controller has superior nominal performance in some areas, particularly sideslip attentuation. C1 USAF, Res Lab, VACC, Wright Patterson AFB, OH 45433 USA. RP Schumacher, CJ (reprint author), USAF, Res Lab, VACC, Wright Patterson AFB, OH 45433 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU EUROPEAN CONFERENCE PUBLICATIONS PI CAMBRIDGE CB4 4RT PA PO BOX 806 COTTENHAM, CAMBRIDGE CB4 4RT, ENGLAND BN 0-9526643-1-3 PY 1999 BP 665 EP 672 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Electrical & Electronic; Mathematics, Applied SC Automation & Control Systems; Engineering; Mathematics GA BP59J UT WOS:000085602700076 ER PT B AU Wolfe, HF Camden, MP Wentz, KR Simmons, LW AF Wolfe, HF Camden, MP Wentz, KR Simmons, LW BE Sivasundaram, S TI Determining the peak probability distribution function of the nonlinear random response of a clamped plate SO SECOND INTERNATIONAL CONFERENCE ON NONLINEAR PROBLEMS IN AVIATION & AEROSPACE VOL 1 AND 2 LA English DT Proceedings Paper CT 2nd International Conference on Nonlinear Problems in Aviation and Aerospace CY APR 29-MAY 01, 1998 CL EMBRY RIDDLE AERONAUT UNIV, DAYTONA BEACH, FL SP Int Fed Nonlinear Analysts, Int Fed Informat Proc, Inst Elect & Electr Engineers Inc, Apollo Aerosp Int Inc, Embry Riddle Aeronaut Univ HO EMBRY RIDDLE AERONAUT UNIV AB The peak probability distribution function used in acoustic fatigue modeling has been typically a Rayleigh distribution. The assumption made when using the Rayleigh distribution is that the response of the structure is single mode. While the single mode acoustic fatigue theory is satisfactory for sound pressure levels around 158 dB overall and below, there is evidence in the literature that as levels increase above this level the accuracy of the single mode assumption decreases accordingly. The purpose of the paper is to determine an appropriate peak probability function for a full range of excitation levels for the response of a clamped plate. The dynamic response of a clamped aluminum plate was determined experimentally. The peak probability density functions are compared with known probability density functions. A promising shape was determined for the response peak probability distribution over a full range of high excitation levels for a clamped plate. C1 USAF, Res Lab, VAS, Wright Patterson AFB, OH 45433 USA. RP Wolfe, HF (reprint author), USAF, Res Lab, VAS, Bldg 24C 2145 5th St,Ste 2, Wright Patterson AFB, OH 45433 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU EUROPEAN CONFERENCE PUBLICATIONS PI CAMBRIDGE CB4 4RT PA PO BOX 806 COTTENHAM, CAMBRIDGE CB4 4RT, ENGLAND BN 0-9526643-1-3 PY 1999 BP 787 EP 796 PG 4 WC Automation & Control Systems; Engineering, Aerospace; Engineering, Electrical & Electronic; Mathematics, Applied SC Automation & Control Systems; Engineering; Mathematics GA BP59J UT WOS:000085602700090 ER PT J AU Ledentsov, NN Bimberg, D Ustinov, VM Maximov, MV Alferov, ZI Kalosha, VP Lott, JA AF Ledentsov, NN Bimberg, D Ustinov, VM Maximov, MV Alferov, ZI Kalosha, VP Lott, JA TI Interconnection between gain spectrum and cavity mode in a quantum-dot vertical-cavity laser SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Article ID SURFACE-EMITTING LASERS; ROOM-TEMPERATURE; LOW-THRESHOLD; ZNSE MATRIX; GAAS; REFLECTORS; ARRAYS; GROWTH AB The effect of self-adjustment of the cavity mode in vertical cavity surface-emitting lasers containing three-period InGaAs-GaAs vertically-coupled quantum dots has been observed. The effect originates from a strong modulation of the refractive index near the gain peak, caused by excitons in quantum dots. The possibility of single quantum dot lasing is demonstrated. C1 AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. Tech Univ Berlin, Inst Festkorperphys, D-10623 Berlin, Germany. Belarussian State Univ, Inst Nucl Problems, Minsk 220050, Byelarus. USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Ledentsov, NN (reprint author), AF Ioffe Phys Tech Inst, 26 Polytekhnicheskaya St, St Petersburg 194021, Russia. RI Ustinov, Viktor/J-3545-2013; Maximov, Mikhail/A-8562-2014 NR 21 TC 12 Z9 12 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0268-1242 J9 SEMICOND SCI TECH JI Semicond. Sci. Technol. PD JAN PY 1999 VL 14 IS 1 BP 99 EP 102 DI 10.1088/0268-1242/14/1/016 PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA 158FN UT WOS:000078105500016 ER PT J AU Lin, DY Huang, YS Tiong, KK Pollak, FH Evans, KR AF Lin, DY Huang, YS Tiong, KK Pollak, FH Evans, KR TI Room-temperature phototransmittance and photoluminescence characterization of the AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor structures with varied quantum well compositional profiles SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Article ID MOLECULAR-BEAM EPITAXY; SURFACE SEGREGATION; MODULATION SPECTROSCOPY; MONOLAYER-SCALE; ENERGY-LEVELS; LINE-SHAPE; PHOTOREFLECTANCE; HETEROSTRUCTURES; SPECTRA; GAAS AB We have studied the effects of the two-dimensional electron gas (2DEG) rind indium surface segregation in four pseudomorphic AlGaAs/InGaAs/GaAs high electron mobility transistor structures using room-temperature phototransmittance (PT) and photoluminescence (PL) measurements. The PT spectra from the InGaAs modulation-doped quantum well channel can be accounted for by a lineshape function which is the first-derivative of a step-like two-dimensional density of states and a Fermi level filling factor. A detailed lineshape fit makes it possible to evaluate the Fermi energy, and hence the concentration of 2DEG in addition to the energies of the intersubband transitions. The lowest-lying intersubband transition has been confirmed by a comparison of the PT and PL spectra. From the difference of intersubband transition energies, the surface segregation effects of indium atoms are demonstrated. C1 Natl Taiwan Univ Sci & Technol, Dept Elect Engn, Taipei 106, Taiwan. Natl Taiwan Ocean Univ, Dept Elect Engn, Keelung 202, Taiwan. CUNY Brooklyn Coll, Dept Phys, Brooklyn, NY 11210 USA. CUNY Brooklyn Coll, New York State Ctr Adv Technol Ultrafast Photon M, Brooklyn, NY 11210 USA. USAF, Wright Lab, Solid State Elect Directorate, EDLM, Wright Patterson AFB, OH 45433 USA. RP Huang, YS (reprint author), Natl Taiwan Univ Sci & Technol, Dept Elect Engn, Taipei 106, Taiwan. OI Tiong, Kwong-Kau/0000-0002-4424-3552 NR 31 TC 7 Z9 7 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0268-1242 J9 SEMICOND SCI TECH JI Semicond. Sci. Technol. PD JAN PY 1999 VL 14 IS 1 BP 103 EP 109 DI 10.1088/0268-1242/14/1/017 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA 158FN UT WOS:000078105500017 ER PT S AU Malhotra, RP Yufik, YM AF Malhotra, RP Yufik, YM BE Dasarathy, BV TI Virtual Associative Networks: A new paradigm for Sensor Fusion SO SENSOR FUSION: ARCHITECTURES, ALGORITHMS, AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensor Fusion - Architectures, Algorithms, and Applications III CY APR 07-09, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers DE neurocomputation; cognitive science; Sensor Fusion; Sensor Management; neural networks AB We discuss Virtual Associative Networks (VANs) emd their relevance for addressing computationally prohibitive Sensor Fusion problems (with results in Dynamic Sensor Management). To our knowledge, this discussion of VAN technology for Sensor Fusion is unique and our current result involving VANs for Dynamic Sensor Management is the first of its kind. The following provides methodology, results, and extensions. C1 USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Malhotra, RP (reprint author), USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. NR 6 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 0-8194-3193-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3719 BP 43 EP 50 DI 10.1117/12.341369 PG 8 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Optics SC Engineering; Computer Science; Optics GA BM94A UT WOS:000080193800005 ER PT S AU Gainey, J Blasch, E AF Gainey, J Blasch, E BE Dasarathy, BV TI Development of emergent processing loops as a system of systems concept SO SENSOR FUSION: ARCHITECTURES, ALGORITHMS, AND APPLICATIONS III SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Sensor Fusion - Architectures, Algorithms, and Applications III CY APR 07-09, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers AB This paper describes an engineering approach toward implementing the current neuroscientific understanding of how the primate brain fuses, or integrates, "'information" in the decision-making process. We describe a System of Systems (SoS) design far improving the overall performance, capabilities, operational robustness, and user confidence in Identification (ID) systems and show how it could be applied to biometrics security. We use the physio-associative temporal sensor integration algorithm (PATSIA) which is motivated by observed functions and interactions of the thalamus, hippocampus, and cortical structures in the brain. PATSIA utilizes signal theory mathematics to model how the human efficiently perceives and uses information from the environment. The hybrid architecture implements a possible SoS-level description of the Joint Directors of US Laboratories (JDL) for Fusion Working Group's functional description involving 5 levels of fusion (i.e., Preprocessing, kinematic, situation, threat, and process refinement) and their associated definitions. This SoS architecture proposes dynamic sensor and knowledge-source integration by implementing multiple Emergent Processing Loops (EPL) for Predicting, feature Extracting, Matching, and Searching both static and dynamic databases like MSTAR's PEMS loops. Biologically, this effort demonstrates these objectives by modeling similar processes from the eyes, ears. and somatosensory channels, through the thalamus, and to the cortices as appropriate while using the hippocampus for short-term memory search and storage as necessary. The particular approach demonstrated incorporates commercially available speaker verification (simulating 1D audio/signal inputs) and face recognition (simulating 2D video/image inputs) software and hardware to collect data and extract features to the PATSIA. The PATSIA maximizes the confidence levels for target identification or verification in dynamic situations using a belief filter. The proof of concept described here is easily adaptable and scaleable to other military and nonmilitary sensor fusion applications. C1 USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Sensors Directorate, 2241 Avon Circles, Wright Patterson AFB, OH 45433 USA. EM James.Gainey@sensors.wpafb.af.mil; Erik.Blasch@sensors.wpafb.af.mil NR 12 TC 0 Z9 0 U1 0 U2 4 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3193-1 J9 PROC SPIE PY 1999 VL 3719 BP 186 EP 195 PG 10 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Optics SC Engineering; Computer Science; Optics GA BM94A UT WOS:000080193800018 ER PT S AU Blasch, E Hong, L AF Blasch, E Hong, L BE Dasarathy, BV TI Sensor fusion cognition using belief filtering for tracking and identification SO SENSOR FUSION: ARCHITECTURES, ALGORITHMS, AND APPLICATIONS III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensor Fusion - Architectures, Algorithms, and Applications III CY APR 07-09, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers DE sensor fusion; target recognition; classification; & identification; tracking; cognitive belief filter; HRR AB Humans exhibit remarkable abilities to estimate, filter, predict, and fuse information in target tracking tasks. To improve track quality, we extend previous tracking approaches by investigating human cognitive-level fusion for constraining the set of plausible targets where the number of targets is not known a priori. The target track algorithm predicts a belief in the position and pose for a set of targets and an automatic target recognition algorithm uses the pose estimate to calculate an accumulated target-belief classification confidence measure. The human integrates the target track information and classification confidence measures to determine the number and identification of targets. This paper implements the cognitive belief filtering approach for sensor fusion and resolves target identify through a set-theory approach by determining a plausible set of targets being tracked. C1 SNAT, AFRL, Wright Patterson AFB, OH 45433 USA. RP Blasch, E (reprint author), SNAT, AFRL, 2241 Avion Cir, Wright Patterson AFB, OH 45433 USA. NR 15 TC 6 Z9 7 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 0-8194-3193-1 J9 P SOC PHOTO-OPT INS PY 1999 VL 3719 BP 250 EP 259 DI 10.1117/12.341347 PG 10 WC Engineering, Aerospace; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic; Optics SC Engineering; Computer Science; Optics GA BM94A UT WOS:000080193800024 ER PT J AU Butler, JT Bright, VM Saia, RJ AF Butler, JT Bright, VM Saia, RJ TI Investigation of MEMS packaging using multichip module foundries SO SENSORS AND MATERIALS LA English DT Article DE multichip modules; micro-electromechanical systems; packaging ID POLYSILICON; POLYIMIDE; ABLATION AB An investigation of the feasibility of packaging micro-electromechanical systems (MEMS) using advanced multichip module (MCM) foundry processes has been conducted. MCM packaging provides an efficient solution for the integration of MEMS with other microelectronic technologies. The MCM foundries investigated for MEMS packaging were the General Electric high-density interconnect (HDI) and chip-on-flex (COF) as well as the Micro Module Systems (MMS) MCM-D process. Bulk and surface micromachined test dies were packaged with CMOS electronics using these MCM foundries. Procedures were developed to successfully release and assemble the MEMS devices without degrading the MCM package or other die in the module. The use of MCM foundries enables the cost-effective development of microsystems in situations where monolithic integration of MEMS and microelectronics is not suitable. C1 USAF, Inst Technol, Dept Elect Engn, Wright Patterson AFB, OH 45433 USA. Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. GE Co, Corp Res & Dev, Schenectady, NY 12301 USA. NR 24 TC 2 Z9 2 U1 0 U2 1 PU MYU, SCIENTIFIC PUBLISHING DIVISION PI TOKYO PA 1-23-3-303 SENDAGI, TOKYO, 113-0022, JAPAN SN 0914-4935 J9 SENSOR MATER JI Sens. Mater. PY 1999 VL 11 IS 2 BP 87 EP 104 PG 18 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA 190XJ UT WOS:000079990300002 ER PT S AU Ferris, DD Currie, NC AF Ferris, DD Currie, NC BE Carapezza, EM Law, DB TI A survey of current technologies for through-the-wall surveillance (TWS) SO SENSORS, C31, INFORMATION, AND TRAINING TECHNOLOGIES FOR LAW ENFORCEMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensors, C31, Information, and Training Technologies for Law Enforcement CY NOV 03-05, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, Battelle, Pacific NW Natl Lab DE through-the-wall surveillance; millimeter wave radar; millimeter wave radiometry; microwave radar AB Recently, a survey was conducted for the Joint Project Steering Group (JPSG) of the National Institute of Justice (NIJ) and Defense Advanced Project Research Agency (DARPA) in to determine the state-of-the-art at the present time in through-the-wall surveillance (TWS) technology and the expected advances within the next 10 years. The applicable technologies for TWS include: impulse radar, UHF/microwave radar, millimeter wave radar, millimeter wave radiometry, X-ray transmission and reflectance, and acoustics. Proposed sensors include: monostatic radar, bistatic (or multistatic) radar, radiometers, fixed antenna systems, scanning systems, and focal plane array systems. The ability to penetrate walls leads to a natural conflict between the desired to successfully penetrate walls which implies lower frequencies and the desire to obtain maximum resolution which implies higher frequencies. Another conflict involves sophistication of the sensor versus unit cost. These issues and the approaches taken by various developers to find workable solutions are discussed. C1 USAF, Res Lab, AFRL, IFEA, Rome, NY 13441 USA. RP Ferris, DD (reprint author), USAF, Res Lab, AFRL, IFEA, Rome, NY 13441 USA. NR 5 TC 12 Z9 12 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 0-8194-3043-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3577 BP 62 EP 72 PG 11 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BM46J UT WOS:000078815100007 ER PT S AU Walter, SM Amodio, M Ratley, RJ AF Walter, SM Amodio, M Ratley, RJ BE Carapezza, EM Law, DB TI Audio processing technology for law enforcement SO SENSORS, C31, INFORMATION, AND TRAINING TECHNOLOGIES FOR LAW ENFORCEMENT SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Sensors, C31, Information, and Training Technologies for Law Enforcement CY NOV 03-05, 1998 CL BOSTON, MA SP Soc Photo Opt Instrumentat Engineers, Battelle, Pacific NW Natl Lab DE audio processing; speech enhancement; speaker recognition; speaker verification; speaker identification; language translation; language identification; dialect identification; gisting; co-channel separation AB The Air Force Research Laboratory Multi-Sensor Exploitation Branch (AFRL/IFEC) has been a Department of Defense leader in research and development (R&D) in speech and audio processing for over 25 years. Their primary thrust in these R&D areas has focused on developing technology to improve the collection, handling, identification, and intelligibility of military communication signals. The National Law Enforcement and Corrections Technology Center for the Northeast (NLECTC-NE), is co-located with the AFRL Rome Research Site(d) at the Griffiss Technology Park in upstate New York. The NLECTC-NE supports sixteen (16) states in the northeast sector of the United States and is funded and supported by the National Institute of Justice(NIJ). Since the inception of the NLECTC-NE in 1995, the AFRL Rome Research Site has expanded its military applications of their expertise to address law enforcement and corrections requirements. AFRL/IFEC's speech and audio processing technology is unique and particularly appropriate for application to law enforcement requirements. It addresses the similar, military need for time-critical decisions and actions, operation within noisy environments, and use by uncooperative speakers in tactical, real-time applications. Audio and speech processing technology for both application domains must also often deal with short utterance communications (less than five seconds of speech) and transmission-to-transmission channel variability. C1 IFEC, AFRL, Informat Directorate, AF Res Lab, Rome, NY 13441 USA. RP Walter, SM (reprint author), IFEC, AFRL, Informat Directorate, AF Res Lab, 32 Brooks Rd, Rome, NY 13441 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3043-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3577 BP 182 EP 187 DI 10.1117/12.336963 PG 6 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BM46J UT WOS:000078815100018 ER PT S AU Gamiz, VL Belsher, JF AF Gamiz, VL Belsher, JF BE Fujisada, H Lurie, JB TI Performance limitations of a four channel polarimeter in the presence of detection noise SO SENSORS, SYSTEMS, AND NEXT-GENERATION SATELLITES III 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 III CY SEP 20-23, 1999 CL FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy DE polarized light; polarimetry; Stokes parameters; Mueller calculus; statistical optics; low light level detection AB We examine the performance limitations of a four-channel polarimeter in the presence of detection noise for arbitrary light levels. We treat the case where the light exiting the polarimeter is detected by a photon counting sensor at each of the four channels. Specifically, we theoretically describe the propagation of detection noise through the polarimeter calibration matrix. The variances in the four estimated Stokes vector components, both orthogonal intensities and mutual phase delay are theoretically predicted for photon counting noise following Poison statistics, and additive Gaussian detection noise. The variances of these parameters depend on the average number of photons incident on the polarimeter, the root-mean-square read noise; and the polarimeter calibration matrix. This methodology allows for including fixed errors in the polarimeter calibration matrix. Various polarimeter designs, whose calibration matrices are known exactly, are examined for high, low and very low light levels. Theoretical performance curves are shown for various sensor parameters and light levels. The theoretically predicted values are compared to simulated results. Excellent agreement between theory and simulation is shown. The simulation also validates the use of the Gaussian probability density function for the parallel (in-phase) and normal components of the phase fluctuations, and results in an accurate theoretical prediction of phase delay fluctuations for arbitrary light levels. The phase delay noise cloud is illustrated for several cases. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Gamiz, VL (reprint author), USAF, Res Lab, AFRL DEBS Bldg 422,3550 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 0-8194-3465-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3870 BP 87 EP 99 DI 10.1117/12.373167 PG 13 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BP56D UT WOS:000085492800010 ER PT S AU O'Connor, L Lawrence, RB AF O'Connor, L Lawrence, RB BE Fujisada, H Lurie, JB TI National Polar-orbiting Operational Environmental Satellite System (NPOESS) Interface Data Processing Segment (IDPS) SO SENSORS, SYSTEMS, AND NEXT-GENERATION SATELLITES III 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 III CY SEP 20-23, 1999 CL FLORENCE, ITALY SP Univ Florence, Dept Earth Sci, European Opt Soc, SPIE, CNR, NASA, Italian Soc Opt & Photon, Italian Space Agcy DE NPOESS; DMSP; FOES; DoD; DOG; polar-orbiting; environmental satellites; data processing; IDPS AB On May 5, 1994, President Clinton made the landmark decision to merge the United States' (US') military and civil operational meteorological satellite systems into a single, national system capable of satisfying both civil and national security requirements for space-based remotely sensed environmental data. For the first time, the US government is taking an integrated approach to identifying and meeting the operational satellite needs of both the civil and national security communities. The joint program formed as a result of President Clinton's direction is known as the National Polar-orbiting Operational Environmental Satellite System (NPOESS). Key to the success of the convergence process are continuing efforts to achieve commonality in the ground data processing segment across US government organizations, in particular within the Departments of Defense (DoD) and Commerce (DOC). The current plans are that five environmental data processing centers, as well as numerous globally-deployed remote field terminals will process the huge volume of satellite data expected to flow from the NPOESS converged satellite system. C1 USAF, Natl Polar Orbiting Operat Environm Satellite Sys, Integrated Program Off, Silver Spring, MD 20910 USA. RP Lawrence, RB (reprint author), NOAA, NESDIS, Natl Polar Orbiting Operat Environm Satellite Sys, Integrated Program Off, Silver Spring, MD 20910 USA. NR 11 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 0-8194-3465-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3870 BP 562 EP 574 DI 10.1117/12.373164 PG 13 WC Engineering, Aerospace; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BP56D UT WOS:000085492800059 ER PT S AU Flanders, L Hartnett, M Vannicola, V AF Flanders, L Hartnett, M Vannicola, V BE Drummond, OE TI Generic evaluation tracker database for OTH radar SO SIGNAL AND DATA PROCESSING OF SMALL TARGETS 1999 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 1999 CY JUL 20-22, 1999 CL DENVER, CO SP SPIE DE radar; OTH; tracker; detection; clutter; database; equalization; superposition AB This paper provides a real world target and clutter model for evaluation of radar signal processing algorithms. The procedure is given for target and clutter data collection which is then followed by the equalization and superposition method. We show how the model allows one to vary the target signal to clutter noise ratio so that system performance may be assessed over a wide range of target amplitudes, i.e. detection probability versus target signal to noise ratio. Three candidate pre-track algorithms are evaluated and compared using this model as input in conjunction with an advanced tracker algorithm as a post processor. Data used for the model represents airborne traffic operating over the body of water bounded by North, Central, and South America. The processors relate to the deployment of Over the Horizon Radar for drug interdiction. All the components of this work, model as well as the processors, are in software. C1 USAF, Res Lab, Surveillance Radar Technol Branch, Griffiss AFB, NY 13441 USA. RP Flanders, L (reprint author), USAF, Res Lab, Surveillance Radar Technol Branch, Griffiss AFB, NY 13441 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3295-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3809 BP 164 EP 173 DI 10.1117/12.364017 PG 10 WC Engineering, Aerospace SC Engineering GA BN96H UT WOS:000083674300015 ER PT S AU Wright, CHG de Graaf, PW Barrett, SF Ferguson, RD AF Wright, CHG de Graaf, PW Barrett, SF Ferguson, RD BE Drummond, OE TI Signal processing for robotically assisted laser photocoagulation of the retina SO SIGNAL AND DATA PROCESSING OF SMALL TARGETS 1999 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 1999 CY JUL 20-22, 1999 CL DENVER, CO SP SPIE DE retina; retinal tracking; photocoagulation; retinal surgery; diabetic retinopathy; reflectance ID REFLECTANCE FEEDBACK-CONTROL; DIABETIC-RETINOPATHY; COAGULATION AB A new system for robotically assisted retinal surgery requires real-time signal processing of the reflectance signal from small targets on the retina. Laser photocoagulation is used extensively by ophthalmologists to treat retinal disorders such as diabetic retinopathy and retinal breaks. Currently, the procedure is performed manually and suffers from several drawbacks which a computer-assisted system,could alleviate. Such a system is under development that will rapidly and safely place multiple therapeutic lesions at desired locations on the retina in a matter of seconds. This system provides real-time, motion-stabilized lesion placement for typical clinical irradiation times (100 ms). A reflectance signal from a small target on the retina is used to derive high-speed tracking corrections to compensate for patient eye movement by adjusting the laser pointing angles. Another reflectance signal from a different small target on the retina is used to derive information to control the laser irradiation time which allows consistent lesion formation over any part of the retina. This paper describes the electrooptical system which dynamically measures the two reflectance signals, determines the appropriate reflectance parameters in realtime, and controls laser pointing and irradiation time to meet the stated requirements. 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 27 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 0-8194-3295-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3809 BP 184 EP 195 DI 10.1117/12.364020 PG 12 WC Engineering, Aerospace SC Engineering GA BN96H UT WOS:000083674300017 ER PT S AU Diemunsch, J Doria, D Chao, A AF Diemunsch, J Doria, D Chao, A BE Kadar, I TI Sensor to Shooter Information Fusion for Rapid Targeting (SSIFRT) SO SIGNAL PROCESSING, SENSOR FUSION, AND TARGET RECOGNITION VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Signal Processing, Sensor Fusion, and Target Recognition VIII CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE AB This paper describes the Sensor to Shooter Information Fusion for Rapid Targeting (SSIFRT) program. The objective of this program is to design, develop, test, and demonstrate the fusion of intelligence, surveillance, and reconnaissance (ISR) data with on-board sensor data. This decentralized information fusion system will take advantage of both on-board tactical platform and off-board sensor data to generate a high performance identification capability. The algorithm development will address Automatic Target Recognition (ATR), ground target tracking, target cueing, and registration of imagery residing on both ground station (off-board) and tactical aircraft (on-board) systems. Analysis of data link and processing requirements/capabilities will be performed to determine an on-board and off-board fusion architecture. The off-board component would be targeted for ground station applications where multiple sources of information will come together. The off-board fusion algorithm employs a Bayesian approach to integrate information from multiple image sources such as SAR, EO, and FLIR as well as non-image based intelligence sources such as Ground Moving Target Indicators (GMTI). Model-based ATR technology will be an important module of this off-board fusion system for the extraction of target information from image data sources. Compression techniques and innovative representations of information will be investigated so that information can be transferred to the shooter platform using existing or planned communication channels. Finally, the tactical platform's on-board system will incorporate a fused feature methodology that utilizes off-board cues and on-board SAR and FLIR imagery for final on-board target identification. C1 SNAA, AFRL, Wright Patterson AFB, OH 45433 USA. RP Diemunsch, J (reprint author), SNAA, AFRL, Wright Patterson AFB, OH 45433 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3194-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3720 BP 320 EP 329 DI 10.1117/12.357172 PG 4 WC Mathematics, Applied; Imaging Science & Photographic Technology SC Mathematics; Imaging Science & Photographic Technology GA BN77R UT WOS:000082902100031 ER PT S AU Keller, JG Matechik, S Rogers, SK Kabrisky, M AF Keller, JG Matechik, S Rogers, SK Kabrisky, M BE Kadar, I TI A model of human vision to register and fuse video imagery SO SIGNAL PROCESSING, SENSOR FUSION, AND TARGET RECOGNITION VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Signal Processing, Sensor Fusion, and Target Recognition VIII CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE human vision; video mosaic; saccadic behavior; Gabor; frame fusion; object recognition AB Modern capture and storage of digital information have given rise to tremendous repositories of data, but the ability to efficiently and effectively use this data has lagged. A prominent example is the generation of video imagery by Unmanned Aerial Vehicles. This imagery currently must be analyzed by a human observer either in real-time or playback mode (dynamic or frame-by-frame), These manpower-intensive activities become increasingly unpalatable as personnel resources shrink, so an automated system is desired that will assist in transforming the large data sets into vastly smaller sets that still retain the pertinent information. We propose a computational vision model based on physiological and behavioral characteristics of the human visual system to perform the registration of multiple video frames, followed by a fusion process that produces a video mosaic preserving the 'important' features (those the human observer would deem important) from each individual frame. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Keller, JG (reprint author), USAF, Inst Technol, 2950 P st, Wright Patterson AFB, OH 45433 USA. NR 20 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 0-8194-3194-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3720 BP 366 EP 375 DI 10.1117/12.357177 PG 4 WC Mathematics, Applied; Imaging Science & Photographic Technology SC Mathematics; Imaging Science & Photographic Technology GA BN77R UT WOS:000082902100036 ER PT B AU Soref, RA AF Soref, RA BE Bisi, O Campisano, SU Pavesi, L Priolo, F TI Microphotonics in-and-on silicon (state of the art and perspectives) SO SILICON-BASED MICROPHOTONICS: FROM BASICS TO APPLICATIONS SE PROCEEDINGS OF THE INTERNATIONAL SCHOOL OF PHYSICS ENRICO FERMI LA English DT Proceedings Paper CT International School of Physics Enrico Fermi on Silicon-Based Microphotonics - From Basics to Applications CY JUL 21-31, 1998 CL VARENNA LAKE COMO, ITALY SP Italian Phys Soc ID INTERSUBBAND LASERS; WAVE-GUIDES; LOW-COST; OPTOELECTRONICS; CIRCUITS; MODULATION; UNIPOLAR; PROGRESS; SYSTEMS; CHIP C1 SNHC, AFRL, Sensors Directorate, Air Force Res Lab, Hanscom AFB, MA 01731 USA. RP Soref, RA (reprint author), SNHC, AFRL, Sensors Directorate, Air Force Res Lab, Hanscom AFB, MA 01731 USA. NR 78 TC 5 Z9 5 U1 0 U2 0 PU I O S PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS BN 90-5199-502-4 J9 P INT SCH PHYS PY 1999 VL 141 BP 1 EP 20 PG 20 WC Optics; Physics, Condensed Matter SC Optics; Physics GA BN75N UT WOS:000082822200001 ER PT B AU Edwards, AH AF Edwards, AH BE Sundaram, KB Deen, MJ Brown, WD Sah, RE Poindexter, E Misra, D TI Theory of dangling orbital defects at the [100] Si-SiO(2) interface SO SILICON NITRIDE AND SILICON DIOXIDE THIN INSULATING FILMS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 5th International Symposium on Silicon Nitride and Silicon Dioxide Thin Insulating Films CY MAY 02-07, 1999 CL SEATTLE, WA SP Electrochem Soc, Dielect Sci & Technol Div, Electrochem Soc, Electr & High Temp Mat Div ID ELECTRON-SPIN-RESONANCE; SILICON DIOXIDE; PB CENTER; STATES; MODEL; MINDO-3; BOND AB We review the current theoretical understanding of several models for the dangling orbital defects at the [100] Si-SiO(2) interface in the context of recent (29)Si hyperfine data. We find that the Poindexter's original model for the P(b0) defect is in excellent agreement with experiment. However, the dimer model proposed by Edwards is in much better agreement with experiment than the model put forward by Poindexter. C1 USAF, Res Lab, Spave Vehicles Directorate, Washington, DC 20330 USA. RP Edwards, AH (reprint author), USAF, Res Lab, Spave Vehicles Directorate, Washington, DC 20330 USA. NR 34 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 1-56677-228-1 J9 ELEC SOC S PY 1999 VL 99 IS 6 BP 109 EP 119 PG 11 WC Computer Science, Hardware & Architecture; Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Coatings & Films SC Computer Science; Electrochemistry; Engineering; Materials Science GA BN99X UT WOS:000083811800010 ER PT B AU Larsen, JM John, R Russ, SM Maxwell, DC Worth, BD Rosenberger, AH Li, K Porter, WJ AF Larsen, JM John, R Russ, SM Maxwell, DC Worth, BD Rosenberger, AH Li, K Porter, WJ BE Ravichandran, KS Ritchie, RO Murakami, Y TI The role of near-threshold small-crack behavior in life prediction of titanium alloys for use in advanced turbine engines SO SMALL FATIGUE CRACKS: MECHANICS, MECHANISMS, AND APPLICATIONS LA English DT Proceedings Paper CT 3rd Engineering Foundation International Conference on Small Fatigue Cracks CY DEC 06-11, 1998 CL OAHU, HI SP Engn Fdn DE microstructure; small crack; titanium alloy; gamma titanium aluminide; turbine engine ID HIGH-CYCLE-FATIGUE AB Increasingly accurate life prediction models are required to utilize safely the full capability of current and future structural materials in advanced gas turbine engines. As an aid to understanding the role of crack size and threshold crack growth in these life predictions, two classes of material are examined: a conventional high strength titanium alloy and a gamma TiAl intermetallic alloy. Residual life calculations and fatigue life maps are used to illustrate the significance of crack size under realistic loading. Using weight function analyses, it is shown that surface residual stresses can greatly increase the threshold crack size for propagation of surface cracks. In the conventional titanium alloy, large-crack fracture mechanics data appear to be applicable to small fatigue cracks of practical, or inspectable, sizes. In a coarse microstructure of the gamma alloy, however, the scale of small cracks and initial damage can be of the order of microstructural dimensions, leading to rapid crack propagation. Local anisotropy in this material is shown to explain this behavior, leading to guidance for optimizing microstructure to improve durability and useful lifetime under realistic loading conditions. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RP Larsen, JM (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. NR 17 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-08-043011-2 PY 1999 BP 131 EP 142 DI 10.1016/B978-008043011-9/50013-2 PG 12 WC Engineering, Mechanical SC Engineering GA BP92Z UT WOS:000086647400012 ER PT B AU Sensmeier, MD Tibbals, TF AF Sensmeier, MD Tibbals, TF BE Ravichandran, KS Ritchie, RO Murakami, Y TI The role of multiaxial stresses in the development of small fatigue cracks in turbine engine blades SO SMALL FATIGUE CRACKS: MECHANICS, MECHANISMS, AND APPLICATIONS LA English DT Proceedings Paper CT 3rd Engineering Foundation International Conference on Small Fatigue Cracks CY DEC 06-11, 1998 CL OAHU, HI SP Engn Fdn DE multiaxial stress; turbine engine; blade life; fatigue testing; critical plane; strain energy density; von Mises AB The observation that many small fatigue cracks in turbine engine blades originate in regions of multiaxial stress makes it clear that accounting for this multiaxiality in the fatigue assessment process is critical. This paper discusses the results of an ongoing program involving the selection of appropriate fatigue methodologies, the generation of multiaxial fatigue data on a titanium alloy, and the implementation of the selected methodologies and pertinent data to an online blade fatigue test monitoring capability. Several fatigue theories were chosen for further study, including the critical plane approach, strain energy density, and the constant-life diagram (using a multiaxial stress parameter rather than uniaxial stress). Multiaxial fatigue tests have been tailored to evaluate the selected theories critically and provide parameters to calibrate the online monitoring system. Preliminary data from this testing are presented, as well as sample results from the demonstration of the prototype fatigue monitoring system to engine test data. C1 Sverdrup Technol Inc, AEDC Grp, Arnold Engn Dev Ctr, Arnold AFB, TN 37389 USA. RP Sensmeier, MD (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold Engn Dev Ctr, Arnold AFB, TN 37389 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS BN 0-08-043011-2 PY 1999 BP 413 EP 420 DI 10.1016/B978-008043011-9/50038-7 PG 8 WC Engineering, Mechanical SC Engineering GA BP92Z UT WOS:000086647400037 ER PT S AU Sciulli, D Griffin, SF AF Sciulli, D Griffin, SF BE Jacobs, JH TI Hybrid launch isolation system SO SMART STRUCTURES AND MATERIALS 1999: INDUSTRIAL AND COMMERCIAL APPLICATIONS OF SMART STRUCTURES TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 1999 Conference CY MAR 01-04, 1999 CL NEWPORT BEACH, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp, Def Adv Res Projects Agcy, US Army Res Off, USAF Res Lab, Ceram Soc Japan, Intelligent Mat Forum, Japan DE passive isolation; active isolation; hybrid (active/passive) isolation; whole-spacecraft launch vibration isolation AB An innovative new hybrid isolation system has been developed to significantly increase the performance over a passive whole-spacecraft isolation design. The design builds upon the passive design and incorporates active components in parallel to the passive design. This means that if the active system fails, the passive system would be able to handle the isolation requirements. Preliminary results show that significant attenuation can occur using the hybrid isolation system over the passive isolation system. Also, it has been determined that the performance gained by the hybrid isolation system will be dependent on the stiffness of the launch vehicle. As, this stiffness increases compared to the isolator stiffness, the amount of force that can be generated at the resonant isolator mode increases. The launch vehicle stiffness now becomes an important design parameter when developing a whole-spacecraft launch isolation system. 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 5 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 0-8194-3148-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3674 BP 352 EP 359 DI 10.1117/12.351572 PG 8 WC Engineering, Aerospace; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BN39R UT WOS:000081784200034 ER PT S AU Karahalis, GG Agnes, GS AF Karahalis, GG Agnes, GS BE Jacobs, JH TI Preliminary analysis of hybrid launch isolation for spacecraft SO SMART STRUCTURES AND MATERIALS 1999: INDUSTRIAL AND COMMERCIAL APPLICATIONS OF SMART STRUCTURES TECHNOLOGIES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 1999 Conference CY MAR 01-04, 1999 CL NEWPORT BEACH, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp, Def Adv Res Projects Agcy, US Army Res Off, USAF Res Lab, Ceram Soc Japan, Intelligent Mat Forum, Japan DE launch vehicle; vibration; isolation; satellite AB As commercial and government space applications shift to smaller satellites there is an increased need to control the environment loads the satellite must experience during launch. Recently, a passive vibration isolation system was successfully deployed. Seeking to enhance the passive isolator's effects research has shifted to active isolation techniques. This paper summarizes the results of recent research to develop a launch vehicle flight model and suitable environmental conditions to analyze the effectiveness of various passive and hybrid isolation techniques. Results include comparisons of the isolators' performance. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Karahalis, GG (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 9 TC 2 Z9 3 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3148-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3674 BP 360 EP 370 DI 10.1117/12.351573 PG 11 WC Engineering, Aerospace; Engineering, Mechanical; Mechanics; Optics SC Engineering; Mechanics; Optics GA BN39R UT WOS:000081784200035 ER PT S AU Khot, NS AF Khot, NS BE Varadan, VV TI Design of an optimum smart wing to enhance roll performance SO SMART STRUCTURES AND MATERIALS 1999: MATHEMATICS AND CONTROL IN SMART STRUCTURES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 1999 Conference CY MAR 01-04, 1999 CL NEWPORT BEACH, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp, Def Adv Res Projects Agcy, US Army Res Off, USAF Res Lab, Ceram Soc Japan, Intelligent Mat Forum, Japan AB This paper is concerned with designing an optimum flexible wing structure to enhance roll maneuver capability at high dynamic pressures using embedded actuating system. A wing optimized to minimize the weight with constraints on strength for symmetric pull up maneuver and constraints on the frequency distribution was used for this study. Elastic twist and camber is achieved by providing a system of actuating elements distributed within the internal substructure of the wing to provide control forces. The equilibrium equations were developed for the steady roll maneuver of a wing subjected to aerodynamic loads and actuating forces. Optimal control design approach was used to determine the distribution of actuating forces. The total straing energy was calculated as a measure of power requirement to produce twist and camber, to achieve specified flexible roll rate at different Mach numbers. C1 USAF, Res Lab, AFRL, VASD, Wright Patterson AFB, OH 45433 USA. RP Khot, NS (reprint author), USAF, Res Lab, AFRL, VASD, Wright Patterson AFB, OH 45433 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3141-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3667 BP 59 EP 67 DI 10.1117/12.350112 PG 7 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Mathematics, Applied; Mechanics; Optics SC Acoustics; Engineering; Mathematics; Mechanics; Optics GA BN32R UT WOS:000081632600006 ER PT S AU Waters, DP AF Waters, DP BE Varadan, VV TI Comparing direct model reference adaptive control with traditional feedback control in the area of damage mitigation SO SMART STRUCTURES AND MATERIALS 1999: MATHEMATICS AND CONTROL IN SMART STRUCTURES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 1999 Conference CY MAR 01-04, 1999 CL NEWPORT BEACH, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp, Def Adv Res Projects Agcy, US Army Res Off, USAF Res Lab, Ceram Soc Japan, Intelligent Mat Forum, Japan DE adaptive control; damage mitigation; active structures; controller performance AB The incorporation of an active control system into an aerospace structure as part of-a smart structure has raised the issue of: How does the controller respond when the structure is damaged? The answer is usually dependent on the answer to numerous: other questions regarding the type of controller, the type of damage, the application of the smart structure, etc. However, previous research has indicated that the Direct Model Reference Adaptive Control (DMRAC) algorithm has potential in preventing the damaged smart structure from becoming unstable. Maintaining stability following an impact damage is of minimal usefulness if the controller can not also provide satisfactory performance before the damage event. This paper presents the simulation results of research comparing a velocity and position feedback controller with a DMRAC controller. The primary areas of concern were the undamaged performance (damping augmentation) and the damaged performance (stability and steady state response). The traditional controller design performed better before the damage occurred, but the DMRAC controller was significantly better after the damage occurred. C1 USAF Acad, Dept Mech Engn, Colorado Springs, CO 80840 USA. RP Waters, DP (reprint author), USAF Acad, Dept Mech Engn, Colorado Springs, CO 80840 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 0-8194-3141-9 J9 P SOC PHOTO-OPT INS PY 1999 VL 3667 BP 670 EP 678 DI 10.1117/12.350126 PG 3 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Mathematics, Applied; Mechanics; Optics SC Acoustics; Engineering; Mathematics; Mechanics; Optics GA BN32R UT WOS:000081632600062 ER PT S AU Agnes, GS AF Agnes, GS BE Hyde, TT TI Piezoelectric coupling of bladed-disk assemblies SO SMART STRUCTURES AND MATERIALS 1999: PASSIVE DAMPING AND ISOLATION SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Smart Structures and Materials 1999 Conference CY MAR 01-04, 1999 CL NEWPORT BEACH, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp, Def Adv Res Projects Agcy, US Army Res Off, USAF Res Lab, Ceram Soc Japan, Intelligent Mat Forum, Japan DE turbomachinery; vibration absorber; vibration; piezoelectric AB A novel approach for reducing mode localization of bladed-disk assemblies in turbomachinery is presented. A virutal shroud is created with piezoelectric coupling to reduce the sensitivity of the compressor disks to model localization. Both direct and resonant shunts are evaluated using a simple lumped-mass model. Resonant shunts are shown to be effective in reducing localization of certain structural modes. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Agnes, GS (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 9 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 0-8194-3146-X J9 P SOC PHOTO-OPT INS PY 1999 VL 3672 BP 94 EP 103 DI 10.1117/12.349772 PG 10 WC Engineering, Aerospace; Engineering, Mechanical; Mechanics; Materials Science, Composites; Optics SC Engineering; Mechanics; Materials Science; Optics GA BN29Q UT WOS:000081456300009 ER PT S AU Mall, S Hsu, TL AF Mall, S Hsu, TL BE Wereley, NM TI Electromechanical fatigue behavior of graphite/epoxy laminate embedded with piezoelectric actuator SO SMART STRUCTURES AND MATERIALS 1999: 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 Smart Structures and Materials 1999 Conference CY MAR 01-04, 1999 CL NEWPORT BEACH, CA SP SPIE, Soc Exptl Mech, Amer Soc Mech Engineers, BFGoodrich Aerosp, Def Adv Res Projects Agcy, US Army Res Off, USAF Res Lab, Ceram Soc Japan, Intelligent Mat Forum, Japan DE adaptive structure; embedded PZT; electromechanical fatigue; structural integrity; fatigue behavior; fatigue life AB Fatigue behavior of graphite/epoxy laminate, having [0/+/-45/90]s lay-up and embedded with piezoelectric (lead zirconate-titanate, PZT) actuator, was investigated under combined mechanical and electrical cycling loading condition. The PZT was inserted into a cutout area in the two middle 90-degrees plies. Experiments involved cycling of specimens at various maximum stress levels along with the excitation of the embedded actuator from -10 V to -100 V or 10 V to 100 V, which resulted in either in-phase or out-of-phase electrically induced strain relative to the applied mechanical loading or strain. In general, PZT performed better in the out-of phase than in the in-phase electromechanical fatigue condition. The fatigue life of the embedded PZT was more than one million cycles, for the applied maximum stress levels well above its design limit in the out-of phase electromechanical and in only mechanical fatigue conditions. The PZT failed before one million cycles during the in-phase test at the applied maximum stress equal to its design limit. Above this stress level, a sharp drop-off occurred in the fatigue life during the in-phase electromechanical cycling condition. C1 USAF, Inst Technol, ENY, Mat & Mfg Directorate,Res Lab, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, Inst Technol, ENY, Mat & Mfg Directorate,Res Lab, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 8 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 0-8194-3142-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3668 BP 770 EP 778 DI 10.1117/12.350753 PG 9 WC Acoustics; Engineering, Aerospace; Engineering, Mechanical; Optics SC Acoustics; Engineering; Optics GA BN32S UT WOS:000081632900068 ER PT S AU Naclerio, AL Gardner, JW Pollack, MM AF Naclerio, AL Gardner, JW Pollack, MM BE Adler, NE Marmot, M McEwen, B Stewart, J TI Socioeconomic factors and emergency pediatric ICU admissions SO SOCIOECONOMIC STATUS AND HEALTH IN INDUSTRIAL NATIONS: SOCIAL, PSYCHOLOGICAL, AND BIOLOGICAL PATHWAYS SE ANNALS OF THE NEW YORK ACADEMY OF SCIENCES LA English DT Article; Proceedings Paper CT Conference on Socioeconomic Status and Health in Industrial Nations - Social, Psychological, and Biological Pathways CY MAY 10-12, 1999 CL NIH, BETHESDA, MARYLAND SP John D & Catherine T MacArthur Fdn Res Network Socioecon Statius & Hlth, New York Acad Sci HO NIH ID CHILDREN C1 George Washington Univ, Dept Pediat, Lackland AFB, TX 78236 USA. Childrens Natl Med Ctr, Lackland AFB, TX 78236 USA. George Washington Univ, Sch Med, Dept Pediat, Washington, DC 20052 USA. Childrens Natl Med Ctr, Dept Crit Care, Washington, DC 20010 USA. Uniformed Serv Univ Hlth Sci, Dept Epidemiol & Biostat, Bethesda, MD 20814 USA. RP Naclerio, AL (reprint author), Wilford Hall USAF Med Ctr, 2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 8 TC 4 Z9 4 U1 0 U2 2 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 EAST 63RD ST, NEW YORK, NY 10021 USA SN 0077-8923 BN 1-57331-211-8 J9 ANN NY ACAD SCI JI Ann.NY Acad.Sci. PY 1999 VL 896 BP 379 EP 382 DI 10.1111/j.1749-6632.1999.tb08147.x PG 4 WC Health Care Sciences & Services; Health Policy & Services; Public, Environmental & Occupational Health; Social Sciences, Biomedical SC Health Care Sciences & Services; Public, Environmental & Occupational Health; Biomedical Social Sciences GA BP47L UT WOS:000085238100048 PM 10681928 ER PT S AU Heinemann, M AF Heinemann, M BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Solar wind heating by Fermi acceleration SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys AB Heating by Fermi acceleration offers a unifying explanation of several disparate properties of solar wind ions. Inside 1 AU, undamped Alfven wave amplitudes, delta B, decrease less rapidly than the field magnitude, maintaining \delta B\/B greater than or similar to 1 and forming wave fronts about a proton gyroradius thick. Fermi acceleration in the compressible medium heats ions to a thermal speed about equal to the Alfven wave amplitude, \delta V-A\; the heating mechanism is ion reflection from the wave fronts. Because \delta V-A\ similar to rho(1/4), the heating results in a proton polytropic index of 3/2 (while the adiabatic index is 5/3 for a fully ionised gas with three degrees of freedom), consistent with observational results and the observed entropy increase of protons in fast wind between 0.3 and 1 AU. Because ions are heated to a thermal speed that is independent of mass, ion temperature is proportional to mass in accord with observations. Helium and heavy ions, with larger gyroradii than protons, are more efficiently reflected by the wave fronts and cross them with difficulty; they are therefore carried by the wave and have differential velocities with respect to protons of about the Alfven velocity, also in agreement with observations. The Fermi acceleration mechanism is inapplicable to the inner corona where \delta B\/B much less than 1 but offers a plausible explanation of an inference by S. Olbert of a temperature maximum in the outer corona near the Alfven critical point where the wave amplitude is maximum. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Heinemann, M (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 9 TC 4 Z9 4 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 453 EP 456 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700094 ER PT S AU Kahler, SW Crooker, NU Gosling, JT AF Kahler, SW Crooker, NU Gosling, JT BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Exploring ISEE-3 magnetic cloud polarities with electron heat fluxes SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID SECTOR BOUNDARIES; FIELD AB We have used solar wind electron heat fluxes to determine the magnetic polarities of the interplanetary magnetic fields (IMF) during the ISEE-3 observations in 1978-1982. That period included 14 magnetic clouds (MCs) identified by Zhang and Burlaga. The MCs have been modeled as single magnetic flux ropes, and it is generally assumed that they are magnetically closed structures with each end of the flux rope connected to the Sun. The flux rope model is valid only if the magnetic polarity of each MC does not change during the passage of ISEE-3 through the MC. We test this model with the heat flux data, using the dominant heat flux in bidirectional electron heat fluxes to determine the MC polarities. The polarity changes within at least 2, and possibly 6, of the 14 MCs, meaning that those MCs can not fit the model of a single flux rope. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Kahler, SW (reprint author), USAF, Res Lab, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 19 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 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 681 EP 684 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700151 ER PT S AU Kahler, SW Raymond, JC Laming, JM AF Kahler, SW Raymond, JC Laming, JM BE Habbal, SR Esser, R Hollweg, JV Isenberg, PA TI Spectroscopic diagnostics for remote detection of particle acceleration regions at coronal shocks SO SOLAR WIND NINE SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 9th International Solar Wind Conference CY OCT 05-09, 1998 CL NANTUCKET, MA SP Amer Inst Phys ID INTERPLANETARY DISTURBANCES; MASS EJECTIONS; SOLAR; POLARIZATION; EVENTS AB We suggest a possible technique for remotely observing the acceleration of solar energetic ions to E > 1 MeV at coronal shock fronts. It involves the observation of the wings of line emission from ions accelerated in shocks, which could be done with the UVCS experiment on the SOHO spacecraft. UVCS has two UV channels producing stigmatic spectra from 42 are min slits that can observe the Ly alpha and O VI lines, both of which could be broadened with the passage of a shock. In that case, the Ly alpha line formation results from proton charge exchange and collisional excitation of hydrogen atoms, while the broadened O VI lines are due to directly accelerated O5+ ions. The search criterion for candidate SOHO events consists of UVCS observations of coronal regions flanking or ahead of fast (v > 400 km/s) white light CMEs observed with the LASCO coronagraph. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Raymond, JC (reprint author), USAF, Res Lab, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 23 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-865-7 J9 AIP CONF PROC PY 1999 VL 471 BP 685 EP 688 PG 4 WC Astronomy & Astrophysics; Geochemistry & Geophysics SC Astronomy & Astrophysics; Geochemistry & Geophysics GA BN29A UT WOS:000081435700152 ER PT J AU Reynolds, DC Look, DC Wille, T Bajaj, KK Collins, TC Molnar, RJ AF Reynolds, DC Look, DC Wille, T Bajaj, KK Collins, TC Molnar, RJ TI Annealing studies on GaN hydride vapor phase epitaxial layers SO SOLID STATE COMMUNICATIONS LA English DT Article DE disordered systems; crystal growth; impurities in semiconductors AB A dramatic change is observed in the photoluminescence spectrum of a GaN sample after annealing at a temperature of similar to 835 degrees C. The as-grown sample, and the same sample annealed at 830 degrees C, show a single dominant donor-bound-exciton (D-0, X) emission line. After annealing at similar to 835 degrees C, the emission evolves into at least four broader emission lines. increasing the annealing temperature to 840 degrees C reverses the emission spectrum back to the single D-0, X line. Repeating the 835 degrees C anneal again produces the evolved spectrum. We propose a model that can account for all of the spectral lines that are generated by the 835 degrees C anneal. We also suggest some possible explanations for the dramatic changes that occur in the emission spectrum when the annealing is carried out over small temperature intervals. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Wright State Univ, Res Ctr, Dayton, OH 45435 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Emory Univ, Atlanta, GA 30322 USA. Oklahoma State Univ, Stillwater, OK 74078 USA. MIT, Lincoln Lab, Lexington, MA 02173 USA. RP Reynolds, DC (reprint author), Wright State Univ, Res Ctr, Dayton, OH 45435 USA. NR 6 TC 0 Z9 1 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PY 1999 VL 109 IS 11 BP 683 EP 686 DI 10.1016/S0038-1098(99)00016-2 PG 4 WC Physics, Condensed Matter SC Physics GA 176VG UT WOS:000079172100002 ER PT S AU Bochove, EJ Denman, CA Ewart, RM AF Bochove, EJ Denman, CA Ewart, RM BE ElGenk, MS TI Theoretical modeling of nonlinear light scattering in Er-doped fiber amplifiers SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc ID BRILLOUIN-SCATTERING AB The effect of stimulated light scattering on the gain of a three-level, step-index, doubly-clad fiber amplifier is modeled at arbitrary pump - and signal - levels. Spatial population dependence is included by assuming the guide transverse mode structure for signal and Stokes fields. This investigation uses the 1550 nm transition of Er3+ in SiO2 as example The stimulated Brillouin scattering (SBS) threshold is found to be low, in agreement with previous experimental findings. Further calculations support the possibility of employing slightly tilted (at alpha congruent to 0.1 - 02 rad) 2 mm length DFB gratings, spaced at 1-2 m intervals, for the control of SBS based on the principle of backward tunneling-mode ( I = 2) coupling of Stokes radiation. C1 DELO, Air Force Res Lab, Albuquerque, NM 87117 USA. RP Bochove, EJ (reprint author), DELO, Air Force Res Lab, 3550 Aberdeen Ave SE, Albuquerque, NM 87117 USA. NR 12 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 575 EP 581 PG 7 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200091 ER PT S AU Taylor, EW Ewart, R AF Taylor, EW Ewart, R BE ElGenk, MS TI Radiation effects in photonic technologies destined for space applications SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB The widespread application of photonic technologies into new satellite architectures is considered to be imminent. Next generation satellite and space platforms have requirements for increased signal bandwidths, reduced power budgets, electromagnetic compatibility and smaller and lighter payloads. Optical sources, processors, interconnects, switches, routers, modulators, amplifiers and other optically manipulative components and systems are expected to provide improved and reliable performance to existing satellite wired-architectures. Recent advances in identifying, quantifying and differentiating the extent and nature of radiation induced damage for a variety of photonic technologies deemed important for potential and planned space applications and demonstrations are presented. Brief examples and discussions of radiation induced crosstalk in inorganic integrated optic devices, attenuation and conductance changes in organic based SLMs, spatial intensity shifts and depolarization in AO Bragg cells, permanent damage in GaN light emitting diodes, shifts of current thresholds in VCSELs, and permanent damage to the gain in Er - doped fiber optic amplifiers will be presented. The paper will also identify new areas of concern in emerging photonics that will require radiation effects studies. C1 Air Force Res Lab, Kirtland AFB, NM 87117 USA. RP Taylor, EW (reprint author), Air Force Res Lab, 3550 Aberdeen Ave,SE, Kirtland AFB, NM 87117 USA. NR 19 TC 4 Z9 4 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 582 EP 596 PG 15 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200092 ER PT S AU Herbelin, JM Henshaw, TL Rafferty, BD Anderson, BT Tate, RF Madden, TJ Manke, GC Hager, GD AF Herbelin, JM Henshaw, TL Rafferty, BD Anderson, BT Tate, RF Madden, TJ Manke, GC Hager, GD BE ElGenk, MS TI The direct observation of gain on the 1.315 mu m transition of atomic iodine produced by the energy transfer from NCl(a(1)Delta) to I(P-2 (3/2)) SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc ID I(2P1/2); I(2P3/2) AB Gain between the I (P-2(3/2)) and I*(P-2(1/2)) states of atomic iodine at 1.315 mu m was detected in a transverse subsonic flow reactor that produced electronically excited I*(P-2(1/2)) atoms from the efficient energy transfer reaction between NCI (a(1)Delta) metastables and ground state I (P-2(3/2)) atoms. The population inversion was directly observed using a 1.315 mu m tunable diode laser that scanned across the entire I (P-2(3/2)) - I*(P-2(1/2)) hyperfine transition with complete resolution. C1 DELC, Air Force Res Lab, Kirtland AFB, NM 87117 USA. RP Herbelin, JM (reprint author), DELC, Air Force Res Lab, 3550 Aberdeen Ave,SE, Kirtland AFB, NM 87117 USA. NR 11 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 597 EP 601 PG 5 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200093 ER PT S AU Denoyer, KK Ninneman, RR AF Denoyer, KK Ninneman, RR BE ElGenk, MS TI Increasing autonomy of precision spacecraft using neural network adaptive control SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB In recent years, there has been a significant interest in the use of adaptive methods for controlling structures in high precision aerospace applications. This is because adaptive methods offer the potential to autonomously adjust to system characteristics different from those modeled or seen in qualification testing. This is especially true of spacecraft, which are generally tested in a l-g environment. Despite extensive research, it remains extremely difficult to predict on-orbit 0-g behavior. In addition, system dynamics often tend to be time varying. This can take the form of slow changes due to degradation of materials and aging of the spacecraft or sudden failures such as the loss of a sensor or actuator. These events become increasingly likely as spacecraft become more and more complex. By decreasing modeling and testing requirements, lowering operations and maintenance activities that require human intervention, and increasing reliability, adaptive methods have the potential to significantly reduce cost and increase performance of these systems. One class of adaptive control methods are those which utilize artificial neural networks. The use of neural networks has become increasingly mature in a number of areas such as image processing and speech recognition. However, despite a number of publications on the subject, very few instances exist where neural networks have actually been used in control and in particular, structural control applications. The United States Air Force Research Laboratory (AFRL) is currently engaged in advancing adaptive neural control technologies for application to precision space systems. This paper gives an overview of several past and current ground and space based adaptive neural control experiments. C1 Air Force Res Lab, Kirtland AFB, NM 87117 USA. RP Denoyer, KK (reprint author), Air Force Res Lab, Kirtland AFB, NM 87117 USA. NR 11 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 636 EP 641 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200100 ER PT S AU Madison, RW AF Madison, RW BE ElGenk, MS TI A concept for cost-effective, satellite servicing SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB Air, land, and sea vehicles are routinely serviced to increase their availability, flexibility, capability, and life span. Servicing could extend the same benefits to satellites, but is rarely employed because current methods are cost effective only for very expensive satellites. This paper presents a concept to minimize the cost of satellite servicing. It combines requirements for a next-generation of serviceable satellites, with an infrastructure whose cost can be amortized over many servicing missions. This should make servicing cost effective for a wider range of spacecraft. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Madison, RW (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 13 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 642 EP 647 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200101 ER PT S AU Lyke, JC AF Lyke, JC BE ElGenk, MS TI Recent progress in cutting edge packaging technology at AFRL SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB A number of bold initiatives in advanced electronics packaging and processing are providing new ways to build the electronics functions of spacecraft, such as computers and communications functions, over 90% smaller and lighter than present systems. Such technologies will uniquely make possible the vision of "system on a chip", "spacecraft on a chip", and "plug-and-play spacecraft". The initiatives are broken down along the lines of: improved density, lower cost, improved robustness, and smart interfaces. The improved density initiatives include the Highly Integrated Packaging and Processing (HIPP) and Ultra-High Density Interconnect (UHDI) programs. Initiatives to lower cost are also underway at AFRL. The investigation of plastic substrates, developed for space use in the high density interconnect (HDI) process in AFRL programs, has resulted in a technology 50% lower in weight and potentially one-fifth the cost of the previous technology. C1 USAF, Res Lab, Washington, DC 20330 USA. RP Lyke, JC (reprint author), USAF, Res Lab, Washington, DC 20330 USA. NR 6 TC 3 Z9 3 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 709 EP 714 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200112 ER PT S AU Gordon, C King, D Byington, L Lanza, D AF Gordon, C King, D Byington, L Lanza, D BE ElGenk, MS TI Technology transfer of military space microprocessor developments SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB Over the past 13 years the Air Force Research Laboratory (AFRL) has led the development of microprocessors and computers for USAF space and strategic missile applications. As a result of these Air Force development programs, advanced computer technology is available for use by civil and commercial space customers as well. The Generic VHSIC Spaceborne Computer (GVSC) program began in 1985 at AFRL to fulfill a deficiency in the availability of space-qualified data and control processors. GVSC developed a radiation hardened multi-chip version of the 16-bit, Mil-Std- 1750A microprocessor. The follow-to GVSC, the Advanced Spaceborne Computer Module (ASCM) program, was initiated by AFRL to establish two industrial sources for complete: radiation-hardened 16-bit and 32-bit computers and microelectronic components. Development of the Control Processor Module (CPM), the first of two ASCM contract phases, concluded in 1994 with the availability of two sources for space-qualified, 16-bit Mil-Std-1750A computers, cards, multi-chip modules, and integrated circuits. The second phase of the program, the Advanced Technology Insertion Module (ATIM), was completed in December 1997. ATIM developed two single board computers based on 32-bit reduced instruction set computer (RISC) processors. GVSC, CPM, and ATIM technologies are flying or baselined into the majority of today's DoD, NASA, and commercial satellite systems. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Gordon, C (reprint author), USAF, Res Lab, Space Vehicles 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 715 EP 720 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200113 ER PT S AU O'Neil, RR Gardiner, HAB Gibson, JJ AF O'Neil, RR Gardiner, HAB Gibson, JJ BE ElGenk, MS TI The Midcourse Space Experiment (MSX): Selected MWIR terrestrial and earth limb background measurements SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc ID SATELLITE AB The characterization of infrared terrestrial and earth limb backgrounds was a primary objective of MSX (the Midcourse Space Experiment), a BMDO (Ballistic Missile Defense Organization) program to support the requirements for the design and operation of proposed and conceptual infrared surveillance systems. The cryogenic phase of the MSX mission, April 24, 1996 to February 25, 1997, has provided definitive and unique measurements of infrared terrestrial and earth limb backgrounds. The mission provided precise radiometric measures at high spatial resolution in two MWIR (mid wavelength infrared) and four LWIR (long wavelength infrared) bands and characterized the mean radiance and spatial structure in 233 data collection events, nominally 20 to 30 minutes in duration, representing;a wide range of terrestrial and limb phenomena. In this paper we present several examples of terrestrial and limb backgrounds for the two MWIR bands with full width half maximum band widths of 4.22 - 4.36 and 4.24 - 4.45 mu m. C1 USAF, Res Lab, Space Vehicles Directorate, Bedford, MA 01731 USA. RP O'Neil, RR (reprint author), USAF, Res Lab, Space Vehicles Directorate, Bedford, MA 01731 USA. NR 8 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 729 EP 734 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200115 ER PT S AU Dichter, BK McGarity, JO Oberhardt, MR Jordanov, VT Sperry, DJ Huber, AC Pantazis, JA Mullen, EG Ginet, G Gussenhoven, MS AF Dichter, BK McGarity, JO Oberhardt, MR Jordanov, VT Sperry, DJ Huber, AC Pantazis, JA Mullen, EG Ginet, G Gussenhoven, MS BE ElGenk, MS TI Compact Environmental Anomaly SEnsor (CEASE): A new spacecraft instrument for the measurement of the local space environment SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc ID ELECTROSTATIC DISCHARGES; DOSE MEASUREMENTS; CRRES; SATELLITE AB A small, lightweight, and low power, spacecraft instrument, CEASE, has been designed to measure the local space radiation environment. The instrument's on-board processing algorithms use the collected data to generate real-time warnings of the space environment hazards of radiation damage, dielectric charging and single event effects. In addition, CEASE can provide detailed space environment data to aid in analysis of anomalies that may occur on the host spacecraft. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Dichter, BK (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 10 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 735 EP 740 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200116 ER PT S AU Serna, PJ Liechty, GH AF Serna, PJ Liechty, GH BE ElGenk, MS TI Electromagnetic shielding effectiveness of composite material SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB The purpose of this paper is to present an engineering study of the electromagnetic shielding effectiveness bf composite materials used in space applications. The objective of the study is to identify and quantify the important electrical characteristics of composite materials proposed as substitutes for conventional metal-based structural elements of spacecraft. Current design practices utilized by various developers of spacecraft, particularly those with survivability and endurability requirements, employ variations of design constraints which rely on quantifiable and testable control of electromagnetic topology. These design practices are based on extensive knowledge and experience gained through analyses and tests of configurations on metallic structures and metal-enclosed electronics boxes. The purpose of this study is to determine, analytically and experimentally, the relevant electromagnetic characteristics of selected classes of composite material being recommended for inclusion in designs of new spacecraft systems. This study surveyed existing electromagnetic databases to determine known electrical characteristics of various advanced composite materials proposed as substitutes for spacecraft metal-based structures and enclosure materials. Particular attention was focused on determining the utility of this data in quantifying the electromagnetic shielding effectiveness through nominal bulk properties such as resistivity/conductivity and electrical connectivity through bonds/joints. For a select set of composite material, an experimental approach to evaluate the important electromagnetic characteristics of sample configurations was used. Primary material focus of this study is on carbon/epoxy, graphite/epoxy, and carbon/cyanate ester materials. C1 USAF, Res Lab, Space Vehicles Directorate, VSSE, Kirtland AFB, NM 87117 USA. RP Serna, PJ (reprint author), USAF, Res Lab, Space Vehicles Directorate, VSSE, Kirtland AFB, NM 87117 USA. NR 20 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 741 EP 746 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200117 ER PT S AU Cooley, T Seigel, G Thorsos, I AF Cooley, T Seigel, G Thorsos, I BE ElGenk, MS TI Hyperspectral imaging from space: Warfighter-1 SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB The Air Force Research Laboratory Integrated Space Technology Demonstrations (ISTD) Program Office has partnered with Orbital Sciences Corporation (OSC) to complement the commercial satellite's high-resolution panchromatic imaging and Multispectral imaging (MSI) systems with a moderate resolution Hyperspectral imaging (HSI) spectrometer camera. The program is an advanced technology demonstration utilizing a commercially based space capability to provide unique functionality in remote sensing technology. This leveraging of commercial industry to enhance the value of the Warfighter-1 program utilizes the precepts of acquisition reform and is a significant departure from the old-school method of contracting for government managed large demonstration satellites with long development times and technology obsolescence concerns. The HSI system will be able to detect targets from the spectral signature measured by the hyperspectral camera. The Warfighter-1 program will also demonstrate the utility of the spectral information to theater military commanders and intelligence analysts by transmitting HSI data directly to a mobile ground station that receives and processes the data. After a brief history of the project origins, this paper will present the details of the Warfighter-1 system and expected results from exploitation of HSI data as well as the benefits realized by this collaboration between the Air Force and commercial industry. C1 USAF, Res Lab, Space Vehicles Directorate, Albuquerque, NM 87108 USA. RP Cooley, T (reprint author), USAF, Res Lab, Space Vehicles Directorate, 3550 Aberdeen Ave SE, Albuquerque, NM 87108 USA. NR 5 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 747 EP 752 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200118 ER PT S AU Jonas, FM AF Jonas, FM BE ElGenk, MS TI A quick look at the expected thermal environment extremes for SBR LEO concepts SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB The management and distribution of thermal energy is a critical aspect of any satellite design. Incorporation of thermal management concepts early in the system concept development is necessary in order to avoid costly redesigns as the system matures. This paper looks at the expected thermal extremes (full sun and eclipse) for a typical SBR LEO concept with a large planar phased array antenna in order to bound and begin definition of applicable thermal management concepts for these designs. The approach involves application of the energy equation (radiation only) using typical ranges of absorptivity and emissivity for spacecraft materials in order to determine the resulting antenna temperatures (steady state). Radiated power (RF) and power conversion efficiencies (input to RF) were also varied. The results show that the antennas are good thermal radiators as expected, and that the issue with thermal management on the antenna will not necessarily be cooling the antenna electronics but keeping them warm enough to operate, especially in power off conditions. Recommended approaches for addressing these issues are presented in order to initiate inclusion of these preliminary concepts in the design and research process as SBR and related antenna concepts mature. C1 USAF, Res Lab, Space Vehicles Directorate, Nichols Res, Kirtland AFB, NM 87117 USA. RP Jonas, FM (reprint author), USAF, Res Lab, Space Vehicles Directorate, Nichols Res, Phillops Res Site, Kirtland AFB, NM 87117 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 753 EP 758 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200119 ER PT S AU Gerhart, C Gluck, DF Stanley, S AF Gerhart, C Gluck, DF Stanley, S BE ElGenk, MS TI Initial characterization results of metal wick capillary pumps SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB In the past 5 years considerable effort has been invested in understanding and improving capillary pumped loop (CPL) technology and many advances have been made, particularly with respect to evaporator designs. With the development of looped heat pipe (LHP) manufacturing capability and expertise outside the former Soviet Union there has been a push to incorporate LHP technology in CPLs to improve their performance. Of particular interest has been the application of sintered metal wicks in the evaporators. Conventional CPL evaporators used polyethene wicks that are generally limited to a minimum pore size of 10 to lj microns, which severely limited the wicking height of a system against gravity. Metal wicks allow pore sizes to 1 micron and sometimes even less, potentially increasing the wicking height by orders of magnitude. Not only can metal wicks increase the wicking height of the CPL, easing the ground testing restrictions, but thy can also theoretically increase the heat flux density of an evaporator, and the maximum allowable temperature for manufacturability and survival. In addition to the possible benefits stated, there are also disadvantages including heaver evaporators and the higher thermal conductivity of the wick itself, possibly leading to deprime with low power loads acid/or power cycling. In this paper the test results of seven metal wick CPL evaporators will be discussed. including two evaporators built by DTX: and five built by the institute of Thermal Physics in Ekaterinburg, Russia. Initial testing shows very promising results with respect to robustness in power cycling and heat flux capability. C1 USAF, Res Lab, AFRL, VSDV, Kirtland AFB, NM 87117 USA. RP Gerhart, C (reprint author), USAF, Res Lab, AFRL, VSDV, 3550 Aberdeen Ave SE,Bldg 472, Kirtland AFB, NM 87117 USA. NR 2 TC 2 Z9 2 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 938 EP 942 PG 5 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200147 ER PT S AU Croop, HC Leger, KB Lowndes, HB Hahn, SE Barthel, CA AF Croop, HC Leger, KB Lowndes, HB Hahn, SE Barthel, CA BE ElGenk, MS TI Thermo-mechanical cyclic testing of carbon-carbon primary structure for an SSTO vehicle SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB An advanced carbon-carbon structural component is being experimentally evaluated for use as primary load carrying structure for future single-stage-to-orbit (SSTO) vehicles. The component is a wing torque box section featuring an advanced, three-spar design. This design features 3D-woven, angle-interlock skins, 3D integrally woven spar webs and caps, oxidation inhibited matrix, chemical vapor deposited (CVD) oxidation protection coating, and ceramic matrix composite fasteners. The box spar caps are nested into the skins which, when processed together through the carbon-carbon processing cycle, resulted in monolithic box halves. The box half sections were then joined at the spar web intersections using ceramic matrix composite fasteners. This method of fabrication eliminated fasteners through both the upper and lower skins. Development of the carbon-carbon wing box structure was accomplished in a four phase design and fabrication effort, conducted by Boeing, Information, Space and Defense Systems, Seattle: WA, under contract to the Air Force Research Laboratory (AFRL). The box is now set up for testing and will soon begin cyclic loads testing in the AFRL Structural Test Facility at Wright-Patterson Air Force Base (WPAFB), OH. This paper discusses the latest test setup accomplishments and the results of the pre-cyclic loads testing performed to date. C1 USAF, Res Lab, Air Vehicles Directorate, Div Struct, Wright Patterson AFB, OH 45433 USA. RP Croop, HC (reprint author), USAF, Res Lab, Air Vehicles Directorate, Div Struct, 2790 D St,Bldg 65, Wright Patterson AFB, OH 45433 USA. NR 2 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 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 1175 EP 1180 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200179 ER PT S AU Kimmel, RL AF Kimmel, RL BE ElGenk, MS TI Trends in hypersonic boundary layer stability and transition research SO SPACE TECHNOLOGY AND APPLICATIONS INTERNATIONAL FORUM - 1999, PTS ONE AND TWO SE AIP CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT 1999 Space Technology and Applications International Forum (STAIF-99) - Opportunities and Challenges for the New Millennium CY JAN 31-FEB 04, 1999 CL ALBUQUERQUE, NM SP Boeing Co, Lockheed Martin Astronaut, NASA, USAF, Air Force Res Lab, US DOE, IAF 99, Amsterdam, Amer Inst Chem Engineers, AIAA, Amer Astronaut Soc, ASME Int, Amer Inst Aeronaut & Astronaut, Amer Inst Chem Engineers, Heat Transfer & Energ Convers Div, Amer Nucl Soc, Trin Sect, Amer Soc Mech Engineers, Nucl Engn Div & Heat Transfer Div, Inst Elect & Electr Engineers Inc, Nucl & Plasma Sci Soc, NASA Natl Space Grant Coll & Fellowship Program, New Mexico Space Grant Consortium, Profess Aerosp Contractors Assoc AB Boundary layer transition impacts hypersonic vehicle performance more profoundly than low speed vehicle performance. Accurate prediction is difficult due to the sensitivity of transition to initial conditions. Computational tools continue to improve, but their use is limited largely to specialists. Ground testing continues to be a valuable tool, but new facility development is slow. Emphasis on transition control methods will increase as our understanding of the physics of hypersonic transition improves. C1 USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. RP Kimmel, RL (reprint author), USAF, Res Lab, Air Vehicles Directorate, 2645 5th St,Suite 7, Wright Patterson AFB, OH 45433 USA. NR 28 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-243X BN 1-56396-846-0 J9 AIP CONF PROC PY 1999 VL 458 BP 1181 EP 1186 PG 6 WC Engineering, Aerospace; Thermodynamics; Engineering, Multidisciplinary; Geosciences, Multidisciplinary; Multidisciplinary Sciences; Nuclear Science & Technology; Remote Sensing; Physics, Applied; Physics, Multidisciplinary SC Engineering; Thermodynamics; Geology; Science & Technology - Other Topics; Nuclear Science & Technology; Remote Sensing; Physics GA BM78K UT WOS:000079755200180 ER PT S AU Vallado, DA Alfano, S AF Vallado, DA Alfano, S BE Bishop, RH Mackison, DL Culp, RD Evans, MJ TI A future look at space surveillance and operations SO SPACEFLIGHT MECHANICS 1999, VOL 102, PTS I AND II SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 9th Annual Space Flight Mechanics Meeting CY FEB 07-10, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB This paper introduces a concept that could support future space surveillance needs, while meeting fiscal constraint during the development. A brief history is included to provide an introduction into the development of some current systems. In particular, we trace the events of the late 20th century that first compelled nations to devote resources to developing space surveillance capabilities. Because space surveillance ultimately relies on the processing of observational data to determine current and future positions for satellites, we include a summary of the major differential correction techniques. The goal is to introduce some of the more common differential correction techniques in use today with an emphasis on the computational requirements for each technique. The computational aspect is a key area to investigate for any future system. The Orbit Determination Interactive Network (ODIN) concept is then explored as a candidate technique that embraces proven military structure (centralized control and decentralized execution), and combines robust survivability, redundancy, accuracy, scaleability, and fiscal conservatism to provide maximum capability to the military and civilian space users of today and tomorrow. Our focus is on a military solution and use, but we recognize the importance, and foresee the ultimate solution being a combined international resource that will operate much as the Federal Aviation Administration (FAA) operates today. A discussion is presented to give the advantages of this type of system and some tough questions that may be asked. We conclude with a brief discussion of how to implement this type of strategy. C1 USAF, USSPACECOMAN, Peterson AFB, CO 80914 USA. RP Vallado, DA (reprint author), USAF, USSPACECOMAN, 250 S Peterson Blvd,Suite 116, Peterson AFB, CO 80914 USA. NR 19 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 0-87703-458-3 J9 ADV ASTRONAUT SCI PY 1999 VL 102 BP 139 EP 157 PN 1&2 PG 19 WC Engineering, Aerospace SC Engineering GA BN45R UT WOS:000081956900011 ER PT S AU Sabol, C Burns, R McLaughlin, CA AF Sabol, C Burns, R McLaughlin, CA BE Bishop, RH Mackison, DL Culp, RD Evans, MJ TI Satellite formation flying design and evolution SO SPACEFLIGHT MECHANICS 1999, VOL 102, PTS I AND II SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 9th Annual Space Flight Mechanics Meeting CY FEB 07-10, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB This study investigates several satellite formation flying designs and their evolution through time. Satellite formation flying designs are derived from the linearized equations of relative motion under two body dynamics better known as Hill's equations. The formations are then propagated forward in time in the presence of realistic perturbations to determine the stability of each design. Formations considered include in-plane, in-track, circular, and projected circular designs. The Draper Semianalytic Satellite Theory (DSST) is used to propagate mean elements of the satellites. When perturbations disrupt the satellite formations, an effort is made to quantify the cost of formation-keeping maneuvers. The goal of this effort is to provide physical insight into satellite formation flying design and outline the effects of realistic dynamics on those designs. C1 USAF, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Sabol, C (reprint author), USAF, Space Vehicles Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 18 TC 2 Z9 2 U1 0 U2 4 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-458-3 J9 ADV ASTRONAUT SCI PY 1999 VL 102 BP 265 EP 284 PN 1&2 PG 20 WC Engineering, Aerospace SC Engineering GA BN45R UT WOS:000081956900018 ER PT S AU Gallagher, K AF Gallagher, K BE Bishop, RH Mackison, DL Culp, RD Evans, MJ TI Optimization of ascent trajectory and related design issues for an aerial propellant transfer Rocketplane SO SPACEFLIGHT MECHANICS 1999, VOL 102, PTS I AND II SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 9th Annual Space Flight Mechanics Meeting CY FEB 07-10, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB Pioneer Rocketplane is designing and building a new reusable launch vehicle, to begin commercial operations in 2001. The "Pathfinder" rocketplane uses the technique of "aerial propellant transfer" to enable lower costs for reaching orbit without using unproven technologies. The optimum trajectory and design-tradeoffs for this concept are very different from pure rocket vehicles or others using highly advanced propulsion technology. Design trades showed that a lower altitude for beginning rocket-powered flight produced higher performance by reducing dry weight of wings and air-breathing engines. Staging conditions were constrained by payload environmental requirements, first stage reentry limits, and second stage trajectory optimization, limiting staging to a narrow range of conditions. C1 Pioneer Rocketplane, Vandenberg AFB, CA 93437 USA. RP Gallagher, K (reprint author), Pioneer Rocketplane, POB 5236, 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 0-87703-458-3 J9 ADV ASTRONAUT SCI PY 1999 VL 102 BP 397 EP 406 PN 1&2 PG 10 WC Engineering, Aerospace SC Engineering GA BN45R UT WOS:000081956900025 ER PT S AU Vallado, DA AF Vallado, DA BE Bishop, RH Mackison, DL Culp, RD Evans, MJ TI Software for astrodynamics SO SPACEFLIGHT MECHANICS 1999, VOL 102, PTS I AND II SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 9th Annual Space Flight Mechanics Meeting CY FEB 07-10, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The technological growth in computers over the past decade or two has been un-paralled in history. In fact we now possess the capability to perform calculations that were only theoretical due to their extreme computational requirements. Much of the work in astrodynamics requires these type of extensive mathematical calculations and. the demands placed on computing software are rapidly rising. Most computer code is closely guarded-a fact that preserves job security, but also introduces significant re-invention and cost to new engineers. This paper introduces a concept of programming to introduce the young engineer to the complex world of computer programming for astrodynamics. It also provides a baseline of programs for the seasoned veteran to extend his repertoire. Specifically, I present algorithms to perform most of the rudimentary calculations for simple astrodynamic analyses. These codes are designed to produce technically correct answers on any computer platform, in PASCAL, FORTRAN, and C. The goal is to have a library of routines that can be tested, modified, expanded, and used for analytical work. The paper does not list all the source code as it would take significant space to do so. Rather, the formal parameters are given, and an example is shown to illustrate how to combine the routines into a working program. Sophisticated graphical and text menu programs are not included as they quickly limit the software to a particular hardware/software configuration. C1 USAF, USSPACECOM AN, Peterson AFB, CO 80914 USA. RP Vallado, DA (reprint author), USAF, USSPACECOM AN, 250 S Peterson Blvd,Suite 116, Peterson AFB, CO 80914 USA. NR 11 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 0-87703-458-3 J9 ADV ASTRONAUT SCI PY 1999 VL 102 BP 811 EP 834 PN 1&2 PG 24 WC Engineering, Aerospace SC Engineering GA BN45R UT WOS:000081956900052 ER PT S AU Luu, K Sabol, C Culp, RD AF Luu, K Sabol, C Culp, RD BE Bishop, RH Mackison, DL Culp, RD Evans, MJ TI Study of perturbation effects on space debris in supersynchronous orbits SO SPACEFLIGHT MECHANICS 1999, VOL 102, PTS I AND II SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 9th Annual Space Flight Mechanics Meeting CY FEB 07-10, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The current debris mitigation measure supported and voluntarily practiced in the geosynchronous (GEO) region is to boost satellites into supersynchronous orbits (SSO) before stationkeeping fuel is expected to be exhausted. Because this solution does not remove mass from space, debris generation by fragmentation events remains a possibility. One concern is the collision hazard between inactive satellites in the SSO region which raises issues regarding the consequences of collisions in this regime and possible interaction with GEO. This paper summarizes the methodology and results of an analytical study of perturbation effects, including solar and lunar third body gravitation, Earth oblateness through degree and order four, and solar radiation pressure, and its application to the analysis of collisions in SSO. In particular, the perturbation analysis seeks to evaluate the altitude variations of the fragmentation debris. Validation of these results by numerical analysis using proven numerical and semianalytical orbit propagators is discussed. Preliminary results show that currently practiced reorbiting distances above GEO do not isolate debris from GEO after the occurrence of collisions in the storage orbit. C1 USAF, Res Lab, AFRL, VSSS, Kirtland AFB, NM 87117 USA. RP Luu, K (reprint author), USAF, Res Lab, AFRL, VSSS, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 19 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 0-87703-458-3 J9 ADV ASTRONAUT SCI PY 1999 VL 102 BP 1053 EP 1072 PN 1&2 PG 20 WC Engineering, Aerospace SC Engineering GA BN45R UT WOS:000081956900066 ER PT S AU Rezzonico, WM Krinsky, CT AF Rezzonico, WM Krinsky, CT BE Bishop, RH Mackison, DL Culp, RD Evans, MJ TI Satellite Tracking using Ambient RF (STAR): Overview SO SPACEFLIGHT MECHANICS 1999, VOL 102, PTS I AND II SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT 9th Annual Space Flight Mechanics Meeting CY FEB 07-10, 1999 CL BRECKENRIDGE, CO SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The Satellite Tracking using Ambient RF (STAR) concept involves a new space surveillance methodology. STAR uses non-cooperative, commercial television transmissions to obtain satellite state vectors and thus may augment the Air Force Space Surveillance Network (SSN). With the number of objects in space increasing, the requirements for space tracking capability are more challenging. However, decreasing budgets make the construction of additional conventional radar sensors unlikely. Existing television transmitters provide a free source of radio frequency (RF) energy for detecting and tracking Low Earth Orbiting (LEO) satellites. Since this technique relies on passive collection, it is relatively inexpensive to operate and maintain. The STAR demonstration had four basic objectives: (1) characterize the environment to determine the availability of RF energy and determine performance limiting constraints (2) detect and track space objects using existing element sets as basis for initial position determination and sensor track initialization (3) detect and track space objects assuming no a-priori knowledge of the element set to demonstrate a capability to detect and track unknown objects, (4) investigate the capabilities, limitations, and cost of the proposed equipment needed for the STAR system. The results indicate that the STAR concept represents a potentially feasible and inexpensive supplement to the current capabilities of the SSN. C1 USAF, Space Battlelab, Space Warfare Ctr, Schriever AFB, CO 80912 USA. RP Rezzonico, WM (reprint author), USAF, Space Battlelab, Space Warfare Ctr, 730 Irwin Ave,Suite 83, Schriever AFB, CO 80912 USA. NR 3 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 0-87703-458-3 J9 ADV ASTRONAUT SCI PY 1999 VL 102 BP 1421 EP 1440 PN 1&2 PG 20 WC Engineering, Aerospace SC Engineering GA BN45R UT WOS:000081956900087 ER PT B AU Liu, CT AF Liu, CT BE Chang, FK TI Application of real-time x-ray technique to monitor damage process in a particulate filled elastomer SO STRUCTURAL HEALTH MONTORING 2000 LA English DT Proceedings Paper CT 2nd International Workshop on Structural Health Monitoring CY SEP 08-10, 1999 CL STANFORD UNIV, STANFORD, CA SP USAF Off Sci Res, USA Res Off, Fed Highway Adm, Natl Sci Fdn HO STANFORD UNIV AB The damage initiation and evolution processes in an edge-cracked sheet specimen subjected to a constant strain rate were investigated using real-time x-ray techniques. The specimens were made of a particulate composite material containing hard particles embedded in a rubber matrix. The x-ray data were analyzed and the results are discussed. C1 USAF, Res Lab, PRSM, Edwards AFB, CA 93524 USA. RP Liu, CT (reprint author), USAF, Res Lab, PRSM, 10 E Saturn Blvd, Edwards AFB, CA 93524 USA. NR 6 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 BN 1-56676-881-0 PY 1999 BP 170 EP 178 PG 9 WC Engineering, Aerospace; Engineering, Civil; Instruments & Instrumentation; Materials Science, Characterization & Testing SC Engineering; Instruments & Instrumentation; Materials Science GA BP03P UT WOS:000083947300016 ER PT B AU Zabinski, JS Voevodin, AA Nainaparampil, JJ Prasad, SV Pierce, NA AF Zabinski, JS Voevodin, AA Nainaparampil, JJ Prasad, SV Pierce, NA BE Kumar, A Chung, YW Moore, JJ Smugeresky, JE TI Novel thin film solid lubricants and hard coatings by pulsed laser based techniques SO SURFACE ENGINEERING: SCIENCE AND TECHNOLOGY I LA English DT Proceedings Paper CT Symposium on Surface Engineering - Science and Technology I held at the 1999 TMS Annual Meeting CY FEB 28-MAR 04, 1999 CL SAN DIEGO, CA SP Minerals Met & Mat Soc, Mat Proc & Mfg Div ID DIAMOND-LIKE CARBON; ZINC-OXIDE FILMS; TRIBOLOGICAL BEHAVIOR; DEPOSITION; MOS2 AB Pulsed laser deposition (PLD) based techniques can be used to grow solid lubricant and hard coatings with chemistry and microstructure optimized for controlling friction and wear in extreme environments such as elevated temperature, high humidity, and outer space. By strategically controlling energy to the growing interface, coating chemistry and microstructure are adjusted in a predictable fashion. In this manuscript, different hybrid PLD configurations and how they permit design and growth of unique coatings (e.g., functional gradients, multilayers, nanostructures, and novel chemistries) are discussed. A review of tribological coatings which includes low friction nanostructured oxides, and composite hard coatings with hard and lubricious phases is provided to illustrate the coating designs attainable. C1 USAF, RL, MLBT, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Zabinski, JS (reprint author), USAF, RL, MLBT, Mat & Mfg Directorate, Bldg 654,2941 P St Ste 1, Wright Patterson AFB, OH 45433 USA. RI Voevodin, Andrey/I-6684-2013 NR 32 TC 1 Z9 1 U1 0 U2 2 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-427-5 PY 1999 BP 127 EP 142 PG 16 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing; Materials Science, Coatings & Films SC Materials Science; Metallurgy & Metallurgical Engineering GA BM95J UT WOS:000080238600012 ER PT S AU Lowry, HS Holt, LL Steely, SL Dalbey, RZ Tonucci, RJ AF Lowry, HS Holt, LL Steely, SL Dalbey, RZ Tonucci, RJ BE Watkins, WR Clement, D Reynolds, WR TI Use of AEDC's laser-based direct write scene generator to drive NAWC's fiber array projector SO TARGETS AND BACKGROUNDS: CHARACTERIZATION AND REPRESENTATION V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Targets and Backgrounds - Characterization and Representation V CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE acousto-optic; scene projection; infrared; radiometric; fiber-optic arrays; crosstalk AB The operation of the Direct Write Scene Generator (DWSG) to drive a fiber array projection system is reported in this paper. The fiber array absorbs the input radiation from the laser-based system and produces broadband infrared output through blackbody cavities fabricated on the ends of the optical fibers. A test program was begun to quantify the performance of the fiber array with respect to input laser, power, temporal response, spatial uniformity, IR output, and fiber-to-fiber crosstalk. Static and dynamic scenes will also be projected with the device and captured with a camera system. Preliminary projection of a simple scene has been accomplished. C1 Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN USA. RP Lowry, HS (reprint author), Sverdrup Technol Inc, AEDC Grp, Arnold AFB, TN USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-3173-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3699 BP 240 EP 248 DI 10.1117/12.352952 PG 9 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BN52F UT WOS:000082112100024 ER PT S AU Murrer, RL Thompson, RA Coker, CF AF Murrer, RL Thompson, RA Coker, CF BE Murrer, RL TI Developments at the Kinetic-Kill Vehicle Hardware-in-the-Loop Simulator (KHILS) facility SO TECHNOLOGIES FOR SYNTHETIC ENVIRONMENTS: HARDWARE-IN-THE-LOOP TESTING IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Technologies for Synthetic Environments - Hardware-in-the-Loop Testing IV CY APR 05-07, 1999 CL ORLANDO, FL SP SPIE DE BMDO; Hardware-in-the-Loop; infrared; LADAR; multi-spectral; projection; resistor array; scene generation; simulation; testing ID INFRARED SCENE PROJECTOR; STEERABLE LASER PROJECTOR; REAL-TIME; RESISTOR ARRAY; GENERATION; INTEGRATION; CAPABILITY AB The Ballistic Missile Defense Organization (BMDO) sponsored the development of the Kinetic Kill Vehicle Hardware-in-the-Loop Simulator (KHILS) to provide a comprehensive ground test capability for end game performance evaluation of BMDO interceptor concepts. Since its inception in 1986, the KHILS facility has been on the forefront of HWIL test technology development. This development has culminated in closed-loop testing involving large format resistive element projection arrays, 3-D scene rendering systems, and real-time high fidelity phenomenology codes. Each of these components has been integrated into a real-time environment that allows KHILS to perform dynamic closed-loop testing of BMDO interceptor systems or subsystems. Ongoing activities include the integration of multiple resistor arrays into both a cold chamber and night motion simulator environment, increasing the update speed of existing arrays to 180 Hz, development of newer 200 Hz snapshot resistor arrays, design of next generation 1024 x 1024 resistor arrays, development of a 1000 Hz seeker motion stage, integration of a resistor array into an RF chamber, and development of advanced real-time plume flow-field codes. This paper describes these activities and test results of the major facility components. C1 USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. RP Murrer, RL (reprint author), USAF, Res Lab, Munit Directorate, 101 W Eglin Blvd, Eglin AFB, FL 32542 USA. NR 30 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 0-8194-3171-0 J9 P SOC PHOTO-OPT INS PY 1999 VL 3697 BP 31 EP 48 PG 18 WC Engineering, Aerospace; Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic; Optics SC Engineering; Computer Science; Optics GA BN65U UT WOS:000082494700004 ER PT S AU Spenny, CH Glassco, RG Green, R AF Spenny, CH Glassco, RG Green, R BE Stein, MR TI Closely supervised control of a target-steered UAV SO TELEMANIPULATOR AND TELEPRESENCE TECHNOLOGIES VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 6th Telemanipulation and Telepresence Technology Conference CY SEP 19-20, 1999 CL BOSTON, MA SP SPIE DE uninhabited aerial vehicle; remotely piloted vehicle; telerobotics; traded control; reactive control; shared control; manual control; supervisory control; man-machine interface AB Orientation of a camera onboard an uninhabited aerial vehicle (UAV) that is used for reconnaissance is performed manually by an operator using a two degree-of-freedom joystick that commands camera azimuth and elevation. The flight path of the UAV is accomplished autonomously by an autopilot that transforms camera orientation into guidance commands that cause the UAV to fly to a destination, loiter or track a target as instructed by the operator. This control mode permits single-person operation of the UAV mission. In a manual mode, the aircraft circles the target at a fixed standoff distance from the UAV that is determined by instantaneous camera orientation and if available, ranging information to the target. The operator must continually track the target in this mode. In a shared control mode, the target location in an earth-fixed frame is determined from the camera orientation at a single point in time, in conjunction with the concurrent UAV position, the latter assumed to be available from GPS or an onboard inertial guidance system. This leaves the operator free to pan for other targets or perform other tasks. He can update target location or switch between the manual and shared modes at any time. This method also provides the added benefit that if the feed from the remote operator is lost, the aircraft will continue on its current heading or loiter similar to current UAV operation. This teleoperation concept is being validated in Wright State University's CAVE automated virtual environment located at Wright Patterson bir Force Base. C1 USAF, Dept Aeronaut & Astronaut, Washington, DC 20330 USA. RP Spenny, CH (reprint author), USAF, Dept Aeronaut & Astronaut, Washington, DC 20330 USA. NR 10 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 0-8194-3433-7 J9 P SOC PHOTO-OPT INS PY 1999 VL 3840 BP 179 EP 190 DI 10.1117/12.369279 PG 12 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Optics SC Automation & Control Systems; Computer Science; Optics GA BP12J UT WOS:000084182600018 ER PT S AU Soref, RA Friedman, L Sun, G Noble, MJ Ram-Mohan, LR AF Soref, RA Friedman, L Sun, G Noble, MJ Ram-Mohan, LR BE Hwu, RJ Wu, K TI Quantum well intersubband THz lasers and detectors SO TERAHERTZ AND GIGAHERTZ PHOTONICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Terahertz and Gigahertz Photonics CY JUL 19-23, 1999 CL DENVER, CO SP SPIE DE terahertz; silicon; germanium; quantum well; detector; laser ID ELECTRON-PHONON SCATTERING; TERAHERTZ LASER; CASCADE LASERS; MU-M; SILICON; EMISSION; MASS AB This paper presents modeling and simulation results on Si-based quantum-well intersubband THz detectors and THz lasers (tasers) in the 3 to 10 THz range where the intersubband transition energy is 12 to 41 meV. The incoherent cryogenically cooled (4K to 20K) quantum well terahertz detector (QWTD) consists of p-type Si0.9Ge0.1 QWs with Si barriers on an Si substrate, or of p-Si0.85Ge0.15/Si on a relaxed Si0.97Ge0.03 buffer on Si. The QWTD senses THz radiation at normal incidence (the XY polarization on the HH1 to LH1 transition) or at edge-illumination (the Z polarization on the HH1 to HH2 transition). Resonant-cavity enhancement, coupling to Si THz waveguides, and integration with SiGe transistor preamplifiers appear feasible for QWTDs. The quantum staircase taser is a simplified far-infrared version of the quantum cascade laser in which each superlattice transfer region is replaced by a thin tunnel-barrier layer. We have adapted to group IV the m-V idea of Sun, Lu, and Khurgin; the "inverted mass taser". On a Si0.81Ge0.19 substrate, we find that an inverted effective mass exists in LH1 at k(x) = 0.013 Angstrom(-1) in 9-nm single-wells of Si0.7Ge0.3 with 5-nm Si barriers. Selective electrical injection of holes into LH1 at T = 77K is postulated. This offers local-in-k-space LH1-HH1 population inversion and tasing at 7.2 THz. Since the taser emission is XY-polarized, the active MQW staircase (a set of identical square QWs) is suitable for insertion into a vertical cavity surface-emitting taser. The VCSET would have resonator thickness of lambda/2n = 6 mu m, and Bragg mirrors constructed from SiO2/Si multilayers. C1 USAF, Res Lab, Sensors Directorate, AFRL,SNHC, Hanscom AFB, MA 01731 USA. RP Soref, RA (reprint author), USAF, Res Lab, Sensors Directorate, AFRL,SNHC, Hanscom AFB, MA 01731 USA. RI Ram-Mohan, Ramdas/C-5167-2012 NR 26 TC 6 Z9 6 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 0-8194-3281-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3795 BP 516 EP 527 DI 10.1117/12.370202 PG 12 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BP33W UT WOS:000084753700056 ER PT S AU Allred, LG AF Allred, LG BE LeMieux, DH Snell, JR TI Minimal entropy reconstructions of thermal images for emissivity correction SO THERMOSENSE XXI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Thermosense XXI CY APR 06-08, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers AB Low emissivity with corresponding low thermal emission is a problem which has long afflicted infrared thermography. The problem is aggravated by reflected thermal energy which increases as the emissivity decreases, thus reducing the net signal-to-noise ratio, which degrades the resulting temperature reconstructions. Additional errors are introduced from the traditional emissivity-correction approaches, wherein one attempts to correct for emissivity either using thermocouples or using one or more baseline images, collected at known temperatures. These corrections are numerically equivalent to image differencing. Errors in the baseline images are therefore additive, causing the resulting measurement error to either double or triple. The practical application of thermal imagery usually entails coating the objective surface to increase the emissivity to a uniform and repeatable value. While the author recommends that the thermographer still adhere to this practice, he has devised a minimal entropy reconstructions which not only correct for emissivity variations, but also corrects for variations in sensor response, using the baseline images at known temperatures to correct for these values. The minimal energy reconstruction is actually based on a modified Hopfield neural network which finds the resulting image which best explains the observed data and baseline data, having minimal entropy change between adjacent pixels. The autocorrelation of temperatures between adjacent pixels is a feature of most close-up thermal images. A suprising result from transient heating data indicates that the resulting corrected thermal images have less measurement error sand are closer to the situational truth than the original data. 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 8 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 0-8194-3174-5 J9 P SOC PHOTO-OPT INS PY 1999 VL 3700 BP 417 EP 424 DI 10.1117/12.342310 PG 8 WC Engineering, Mechanical; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BM93Z UT WOS:000080193300050 ER PT S AU Ghosh, AK Bae, DH Semiatin, SL AF Ghosh, AK Bae, DH Semiatin, SL BE Sakuma, T Aizawa, T Higashi, K TI Initiation and early stages of cavity growth during superplastic and hot deformation SO TOWARDS INNOVATION IN SUPERPLASTICITY II SE MATERIALS SCIENCE FORUM LA English DT Article; Proceedings Paper CT 2nd International Conference on Towards Innovation in Superplasticity CY SEP 21-24, 1998 CL KOBE, JAPAN DE flow incompatibility; interface defect; interface-constrained growth; Ti-6Al-4V alloy; 5083 Al; continuous cavity nucleation AB The formation and growth of internal voids in metallic alloys are of considerable concern in components produced by superplastic and hot forming processes. Grain boundary cavitation, observed under conditions where boundaries are weaker than grain interior, results from concentration of strain around non-deformable particles and hard second phases located at grain boundaries. Careful examination of microstructures of aluminum and titanium alloys show that most voids are "nucleated" due to incompatible deformation between phases, although a few cavities might preexist in certain alloys. Increased levels of local hydrostatic stress arising from plastic constraints can activate growth of interfacial defects leading to rapid dilatation, followed by a slower growth rate due to reduced constraint as voids expand. An interface-constrained plasticity growth model described in this work explains why cavity growth rate is enhanced by increased strain rate, larger particle size, decreasing forming temperature and lower m value (strain rate sensitivity parameter) in metals, not by the diffusional growth mechanism. Experimental studies, utilizing image analysis revealed how the population of cavity nuclei also increase with increasing strain, strain rate and decreasing temperature, supporting the predictions of this new model. C1 Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. USAF, Res Lab, AFRL, MLLM, Wright Patterson AFB, OH 45433 USA. RP Ghosh, AK (reprint author), Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. RI Juhyun, Oh/H-9185-2012; SEMIATIN, SHELDON/E-7264-2017 NR 15 TC 26 Z9 26 U1 0 U2 4 PU TRANSTEC PUBLICATIONS LTD PI ZURICH-UETIKON PA BRANDRAIN 6, CH-8707 ZURICH-UETIKON, SWITZERLAND SN 0255-5476 BN 0-87849-828-1 J9 MATER SCI FORUM PY 1999 VL 304-3 BP 609 EP 616 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Materials Science, Composites SC Materials Science GA BN52G UT WOS:000082112300092 ER PT J AU John, PJ Zabinski, JS AF John, PJ Zabinski, JS TI Sulfate based coatings for use as high temperature lubricants SO TRIBOLOGY LETTERS LA English DT Article DE high temperature lubrication; CaSO4; CaF2; lubricant coating AB Films of CaSO4, BaSO4, and SrSO4 were grown with the pulsed laser deposition technique. The high temperature lubricious properties of these films were evaluated and it was found that all three sulfates exhibited a low coefficient of friction (mu approximate to 0.15) at 600 degrees C. X-ray diffraction studies showed the presence of carbonate crystal structures along with the sulfate crystal structures after testing. The carbonate crystal structure is composed of alternating planes of alkali earth atoms and carbonate ions. The layered structure of the carbonates may be important to the lubricating mechanism as the layered structure of the dichalcogenides contributes to their tribological properties. Various observations of the wear region suggest that the starting surface finish of the metal coupon plays a significant role in the tribological mechanism of these materials. Additional composite films containing CaSO4 were grown with the plasma spray technique. The high temperature friction properties of these films were measured and compared to those of similar films containing CaF2/BaF2. Although both types of films exhibited low coefficients of friction at 600 degrees C, analysis of the wear regions did not show the presence of CaSO4 and CaF2/BaF2, respectively. Ca and/or Ba were present, though, suggesting that a new compound is formed in the wear track and that the sulfate and fluoride phases may not be providing the low friction in these composites. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. USAF, Wright Lab, MLBT, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP John, PJ (reprint author), Univ Dayton, Res Inst, 300 Coll Pk, Dayton, OH 45469 USA. NR 13 TC 27 Z9 28 U1 3 U2 14 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 1023-8883 J9 TRIBOL LETT JI Tribol. Lett. PY 1999 VL 7 IS 1 BP 31 EP 37 DI 10.1023/A:1019140530037 PG 7 WC Engineering, Chemical; Engineering, Mechanical SC Engineering GA 242KW UT WOS:000082940800005 ER PT J AU Waltman, RJ Tyndall, GW Pacansky, J Berry, RJ AF Waltman, RJ Tyndall, GW Pacansky, J Berry, RJ TI Impact of polymer structure and confinement on the kinetics of Zdol 4000 bonding to amorphous-hydrogenated carbon SO TRIBOLOGY LETTERS LA English DT Article DE perfluoropolyether; hard-disk drives; bonding kinetics; film confinement; ab initio; molecular mechanics; chain flexibility ID MOLECULARLY THIN-LAYERS; SIMPLE LIQUIDS; PHASE-TRANSITIONS; SOLVATION FORCES; DYNAMICS; FILMS; FRICTION; GEOMETRY; METHYL-ETHER); SEGREGATION AB The bonding of molecularly-thin (10 Angstrom) Zdol 4000 films to amorphous, hydrogenated carbon (CHx) was investigated as a function of the Zdol structure, i.e., the ratio of the perfluoromethylene oxide (C-1) to perfluoroethylene oxide (C-2) monomer units in the backbone. The influence of the C-1/C-2 ratio on the intrinsic mobility of the Zdol polymer was also investigated by computing the energetic barriers to internal rotation about the C-O and C-C bonds in model compounds by both ab initio and molecular mechanics methods. The calculations indicate that increasing the C-1/C-2 ratio increases the relative flexibility of the Zdol polymer. The kinetic results demonstrate that the rate at which submonolayer Zdol films bond to CHx is non-classical (time-dependent) regardless of the Zdol chain stiffness. The Zdol bonding rate can best be described by a kinetic equation of the form, dB/dt = k(t)A, where the rate coefficient, k(t) can be expressed as a power function in time: k(t) = k(B) t(-h). The values of the initial bonding rate constant, k(B), and the functional form of the time dependence, t(-h), are both strongly dependent on the Zdol backbone flexibility. The magnitude of the initial bonding rate constants generally increase with increasing Zdol chain mobility. A discontinuous change in both the magnitude of k(B) and the functional form of the time dependence is, however, observed at 64(degrees)C when the C-1/C-2 ratio is increased from 0.97 to 1.08. The bonding rate coefficient scales as t(-0.5) for the relatively rigid Zdol backbone structures with C-1/C-2 < 1, while a t(-1.0) time-dependent bonding rate is observed for the more flexible Zdol backbones with C-1/C-2 > 1. The initial rate constant, k(B), also changes abruptly near C-1/C-2 approximate to 1, with k(B) of the flexible Zdol chains (samples with C-1/C-2 > 1) being approximately an order of magnitude greater than the more rigid chains (C-1/C-2 < 1). These results indicate that the physical state of the confined Zdol film can be either liquidlike or solidlike depending upon the molecular stiffness of the backbone employed. The t(-0.5) time-dependent bonding rate is shown to be consistent with a one-dimensional, diffusion-limited reaction from a solidlike Zdol structure, whereas the t(-1.0) bonding rate results when bonding occurs from a liquidlike Zdol film structure. The temperature dependence of the Zdol 4000 bonding rate coefficient for the Zdol backbone characterized by C-1/C-2 = 0.97 (solidlike at T = 64(degrees)C) was found to undergo a transition from a t(-0.5) time dependence for T < 150(degrees)C, to a t(-1.0) time dependence at T > 180. This transition occurs over relatively narrow temperature range (150 < T < 180(degrees)C) and is attributed to a 2D melting of the confined Zdol film. C1 IBM Corp, Storage Syst, San Jose, CA 95193 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Waltman, RJ (reprint author), IBM Corp, Storage Syst, 5600 Cottle Rd, San Jose, CA 95193 USA. NR 56 TC 31 Z9 31 U1 1 U2 2 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 1023-8883 J9 TRIBOL LETT JI Tribol. Lett. PY 1999 VL 7 IS 2-3 BP 91 EP 102 DI 10.1023/A:1019181606355 PG 12 WC Engineering, Chemical; Engineering, Mechanical SC Engineering GA 265ZV UT WOS:000084276900005 ER PT J AU Voevodin, AA O'Neill, JP Zabinski, JS AF Voevodin, AA O'Neill, JP Zabinski, JS TI WC/DLC/WS2 nanocomposite coatings for aerospace tribology SO TRIBOLOGY LETTERS LA English DT Article DE nanocomposite; coating; tribology; aerospace ID DIAMOND-LIKE CARBON; TUNGSTEN DISULFIDE FILMS; PULSED-LASER DEPOSITION; BEHAVIOR; LOAD AB Tribological properties of three-phase composite coatings consisting of nanocrystalline WC, amorphous diamond-like carbon (DLC), and nanocrystalline WS2 are evaluated. The WC/DLC/WS2 coatings have 0.5 mu m thickness, 7-8 GPa hardness, excellent wear resistance, and low friction coefficients: 0.03 in vacuum, and 0.15 in air; with unique friction recovery in cycling between dry and moist environments. The benefits of carbide/dichalcogenide/DLC nanocomposites for aerospace tribology are highlighted. C1 USAF, Res Lab, MLBT, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Voevodin, AA (reprint author), USAF, Res Lab, MLBT, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM voevodaa@ml.wpafb.af.mil RI Voevodin, Andrey/I-6684-2013 NR 25 TC 44 Z9 48 U1 2 U2 16 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 1023-8883 J9 TRIBOL LETT JI Tribol. Lett. PY 1999 VL 6 IS 2 BP 75 EP 78 DI 10.1023/A:1019163707747 PG 4 WC Engineering, Chemical; Engineering, Mechanical SC Engineering GA 183ZM UT WOS:000079584900002 ER PT J AU Helmick, LS Sharma, SK AF Helmick, LS Sharma, SK TI Effect of humidity on wear of M-50 steel with a branched perfluoropolyalkylether lubricant SO TRIBOLOGY LETTERS LA English DT Article DE perfluoropolyalkylether; polyether; PFPAE; relative humidity; friction; wear; Krytox ID FLUID; PERFLUOROPOLYETHERS; SURFACES AB Humidity is an uncontrolled variable in many tribology tests. This report shows that changes in relative humidity can affect wear for all perfluoropolyalkylethers regardless of their molecular structure. Using a Cameron-Plint tribometer under controlled environmental conditions, wear of M-50 steel with a Krytox (a branched perfluoropolyalkylether) lubricant was studied under boundary lubrication conditions at 150(degrees)C in air with relative humidity ranging from 1 to 95%. Both wear and friction decreased sharply as humidity was increased from 1 to 20%, then were constant as the humidity was increased to 95%. Thus, wear is highly dependent on humidity when relative humidity is less than 20%. The similar effect of humidity on wear previously observed for Fomblin Z, a linear perfluoropolyalkylether containing difluoroacetal groups, and Demnum S, a linear perfluoropolyalkylether which does not contain difluoroacetal groups, indicates that this may be a general property of all commercially available perfluoropolyalkylethers, branched as well as linear ones. C1 Cedarville Coll, Cedarville, OH 45314 USA. USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Helmick, LS (reprint author), Cedarville Coll, Cedarville, OH 45314 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 1023-8883 J9 TRIBOL LETT JI Tribol. Lett. PY 1999 VL 6 IS 2 BP 123 EP 127 DI 10.1023/A:1019103521859 PG 5 WC Engineering, Chemical; Engineering, Mechanical SC Engineering GA 183ZM UT WOS:000079584900007 ER PT J AU Canning, GW Fuller, MLS Bancroft, GM Kasrai, M Cutler, JN De Stasio, G Gilbert, B AF Canning, GW Fuller, MLS Bancroft, GM Kasrai, M Cutler, JN De Stasio, G Gilbert, B TI Spectromicroscopy of tribological films from engine oil additives. Part I. Films from ZDDP's SO TRIBOLOGY LETTERS LA English DT Article DE XANES; microscopy; X-ray absorption; antiwear film ID RAY-ABSORPTION-SPECTROSCOPY; CHEMICAL CHARACTERIZATION; ANTIWEAR FILMS; FLUORESCENCE MEASUREMENTS; WEAR; PERFORMANCE; ELECTRON; CONTACT; STEEL; EDGE AB Antiwear films formed from pure neutral alkyl- and aryl-ZDDP's, and a commercial ZDDP, have been studied with high resolution synchrotron-based photoemission spectromicroscopy with a new instrument, MEPHISTO. Good P L-edge XANES spectra have been taken on areas between 12 and 400 mu m(2), and good images of phosphates and ZDDP have been obtained at similar to 1 mu m resolution on both smooth and rough steel. These spectra, and corresponding images, show immediately that both the chemistry and the morphology of the alkyl and aryl films are very different. The alkyl film contains a range of smaller and larger protective polyphosphate pads from a few to similar to 25 mu m(2) in area. We have shown that the chemistry of small and large pads are different. The large pads contain very long chain polyphosphate; while the smaller pads contain short chain polyphosphate. The aryl films contain ortho- or pyro-phosphates, are much thinner and more uniform, with obviously more streaking from initial wear, and no obvious protective pad formation. Antiwear films generated from the commercial ZDDP, rubbed in base oil, show that the long chain polyphosphate is converted to ortho- or pyro-phosphate, but the amount and distribution of phosphate does not change noticeably. The antiwear films are remarkably stable physically. C1 Univ Western Ontario, Dept Chem, London, ON N6A 5B7, Canada. Wright Lab, Wright Patterson AFB, OH 45433 USA. CNR, Inst Struttura Mat, I-00133 Rome, Italy. Ecole Polytech Fed Lausanne, Inst Phys Appl, CH-1015 Lausanne, Switzerland. RP Bancroft, GM (reprint author), Univ Western Ontario, Dept Chem, London, ON N6A 5B7, Canada. RI Gilbert, Benjamin/E-3182-2010; Gilbert, Pupa/A-6299-2010 OI Gilbert, Pupa/0000-0002-0139-2099 NR 40 TC 38 Z9 38 U1 1 U2 9 PU BALTZER SCI PUBL BV PI BUSSUM PA PO BOX 221, 1400 AE BUSSUM, NETHERLANDS SN 1023-8883 J9 TRIBOL LETT JI Tribol. Lett. PY 1999 VL 6 IS 3-4 BP 159 EP 169 DI 10.1023/A:1019176110473 PG 11 WC Engineering, Chemical; Engineering, Mechanical SC Engineering GA 208CW UT WOS:000080973500002 ER PT J AU Forster, NH AF Forster, NH TI Rolling contact testing of vapor phase lubricants - Part III: Surface analysis SO TRIBOLOGY TRANSACTIONS LA English DT Article; Proceedings Paper CT 51st Annual Meeting of the Society-of-Tribologists-and-Lubrication-Engineers CY MAY 19-23, 1996 CL CINCINNATI, OHIO SP Soc Tribologists & Lubricat Engineers DE vapor phase lubrication; lubricants, vapor phase lubricants; surface analytical techniques, chemical; Auger electron spectroscopy; Fourier transform infrared spectroscopy; Raman spectroscopy; energy dispersive X-ray fluorescence ID RAMAN; FILMS; SPECTROSCOPY; TEMPERATURE; DEPOSITION AB Infrared microscopy (mu-FTIR), Raman spectroscopy, Auger electron spectroscopy (AES), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to characterize bearing surfaces lubricated fr om the vapor phase. Results are presented for surface films generated with a tertiary-butyl phenyl phosphate (TBPP) and a polyphenylether (5P4E). Infrared bands consistent with inorganic poly-phosphates and phosphites were detected in deposition films generated with the TBPP lubricant. Raman shifts consistent with graphite of short phosphites were detected in films deposited by both lubricants. However; specimens lubricated by the 5P4E had several Raman shifts consistent with Fe2O3 and Fe3O4. Iron oxides were not detected in deposition films generated with the TBPP lubricant. AES depth profiles indicate a predominant mixture of iron and car-bon in the TBPP deposition film; whereas, the 5P4E film predominantly consists of iron and oxygen. Localized corrosion pitting generated with the TBPP lubricant was analyzed wing AES, SEM, and EDS. The results indicate that a modified matrix rich in phosphorus, oxygen and carbon, with a corresponding depletion of iron, transcends to depths of at least 10 microns in the substrate in damaged regions. Lubrication and failure mechanisms of vapor lubricated bearings are proposed based on the results. C1 AF Res Lab, Wright Patterson AFB, OH 45433 USA. RP Forster, NH (reprint author), AF Res Lab, Wright Patterson AFB, OH 45433 USA. NR 35 TC 23 Z9 23 U1 0 U2 2 PU SOC TRIBOLOGISTS & LUBRICATION ENGINEERS PI PARK RIDGE PA 840 BUSSE HIGHWAY, PARK RIDGE, IL 60068 USA SN 1040-2004 J9 TRIBOL T JI Tribol. Trans. PD JAN PY 1999 VL 42 IS 1 BP 1 EP 9 DI 10.1080/10402009908982183 PG 9 WC Engineering, Mechanical SC Engineering GA 168HT UT WOS:000078686700001 ER PT J AU Forster, NH AF Forster, NH TI Rolling contact testing of vapor phase lubricants - Part IV: Diffusion mechanisms SO TRIBOLOGY TRANSACTIONS LA English DT Article; Proceedings Paper CT 53rd Annual Meeting of the Society-of-Tribologists-and-Lubrication-Engineers CY MAY 17-21, 1998 CL DETROIT, MICHIGAN SP Soc Tribologists & Lubricat Engineers DE vapor phase lubrication; lubricants, vapor phase lubricants; surface analytical techniques, chemical, Auger election spectroscopy; ionic diffusion ID COATINGS; FILMS AB Auger depth profile data, obtained from vapor-lubricated T15 bearing steel, were modeled using the solution for diffusion in a semiinfinite pair A tertiary-butyl phenyl phosphate was used as the vapor lubricant. The primary species undergoing diffusion are iron and carbon. The objective of the experiment was to determine the order of magnitude of the diffusion coefficient and to qualitatively assess what types of diffusion mechanisms are involved. The experimental results indicate that the diffusion profile travels at a velocity equal to the bearing wear rate under dynamic conditions. This is possible if iron diffusions at a: faster rate than carbon, i.e., the Kirkendall effect. Analyses of the data were performed using Darken's equations. The results indicate that the diffusion coefficient of iron is of the order of 1 x 10(-14) cm(2)/s at test temperatures of 370 degrees and 430 degrees C. Diffusion is thought to occur via the migration of iron cations through an anionic lattice of polyphosphate and phosphite, i.e., cation diffusion. The diffusion mechanism provides a satisfactory explanation of how several hundred monolayers containing iron can exist in vapor deposition film grown from organophosphorus lubricants. The chemical gradient, ionic attraction, and the extreme stress gradients of the Hertzian contact are thought to contribute to diffusion under dynamic conditions. C1 AF Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. RP Forster, NH (reprint author), AF Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. NR 23 TC 6 Z9 6 U1 0 U2 1 PU SOC TRIBOLOGISTS & LUBRICATION ENGINEERS PI PARK RIDGE PA 840 BUSSE HIGHWAY, PARK RIDGE, IL 60068 USA SN 1040-2004 J9 TRIBOL T JI Tribol. Trans. PD JAN PY 1999 VL 42 IS 1 BP 10 EP 20 DI 10.1080/10402009908982184 PG 11 WC Engineering, Mechanical SC Engineering GA 168HT UT WOS:000078686700002 ER PT B AU Lehr, JM Baum, CE Prather, WD Torres, RJ AF Lehr, JM Baum, CE Prather, WD Torres, RJ BE Heyman, E Mnadelbaum, B Shiloh, J TI Fundamental physical considerations for ultrafast spark gap switching SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL AB A problem of interest concerns compact, high power ultra-wideband systems which minimize the volume of high pressure gas. Thus, single channel spark gaps are considered because the volume of gas under pressure is much less than that needed for sources containing ring gap switches. However, the intrinsic inductance of single channel spark gaps is prohibitively high to achieve large rates of voltage rise. For future applications, the limit of spark gap technology for ultrafast switching is explored. Specifically, an estimate of the fastest risetime achievable with a single channel spark gap has been investigated using three approaches. The first examines the growth of the electron avalanche in gases to estimate its growth rate. The avalanche growth rate determines the fastest possible risetime of the resultant pulse. The second approach uses the components of the velocity of electromagnetic propagation to estimate the achievable risetime. The third uses an equivalent circuit of a single channel spark gap to calculate the maximum achievable rate of voltage rise. The first two estimates indicate that risetimes on the order of 1-10 ps are achievable. The last treatment, however, illustrates the dependence of the pulse risetime on the peak voltage and calculates the maximum rate of voltage rise to be on the order of 10(16) V/s. To reduce the effect of the intrinsic inductance of the channel, a simple geometrical alteration to the spark gap geometry has been devised which effectively reduces the inductance per unit length of the spark gap to that of its transmission line feed. This simple change alleviates the constraint imposes by the maximum rate of voltage rise and is anticipated to permit the realization of picosecond risetime high power electromagnetic sources. C1 USAF, Res Lab, Phillips Site, High Power Syst Branch, Kirtland AFB, NM 87117 USA. RP Lehr, JM (reprint author), USAF, Res Lab, Phillips Site, High Power Syst Branch, Kirtland AFB, NM 87117 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 11 EP 20 DI 10.1109/UWBSP.1998.818934 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500002 ER PT B AU Yaghjian, AD Hansen, TB AF Yaghjian, AD Hansen, TB BE Heyman, E Mnadelbaum, B Shiloh, J TI Wave equations and transmission formulas for the output of a receiving antenna SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL ID TIME-DOMAIN; FIELD C1 USAF, RL, SNHE, Bedford, MA 01731 USA. RP Yaghjian, AD (reprint author), USAF, RL, SNHE, Bedford, MA 01731 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 57 EP 63 DI 10.1109/UWBSP.1998.818940 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500008 ER PT B AU Baum, CE AF Baum, CE BE Heyman, E Mnadelbaum, B Shiloh, J TI Intermediate field of an impulse-radiating antenna SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL C1 USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. RP Baum, CE (reprint author), USAF, Res Lab, DEHP, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 24 TC 0 Z9 0 U1 1 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 77 EP 89 DI 10.1109/UWBSP.1998.818942 PG 13 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500010 ER PT B AU Buchenauer, CJ Tyo, JS Schoenberg, JSH AF Buchenauer, CJ Tyo, JS Schoenberg, JSH BE Heyman, E Mnadelbaum, B Shiloh, J TI Aperture efficiencies of impulse radiating antennas SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL AB A concept of aperture efficiency is introduced for the purpose of comparing and optimizing the performance of impulse radiating antennas (IRAs). The aperture efficiencies of popular lens and reflector IRAs are computed as the ratios of peak radiated power densities on boresight compared with that produced by an ideal IRA with an aperture of equal area and equal total input power. Loss of aperture efficiency occurs through two distinct mechanisms: from power that falls outside the aperture and is lost; and from nonuniform power and polarization distributions within the aperture. Both loss mechanisms are addressed, and means for increasing efficiencies are identified. Aperture efficiencies approaching 100 % are feasible in TEM-horn arrays and similar structures. C1 USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. RP Buchenauer, CJ (reprint author), USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 91 EP 108 DI 10.1109/UWBSP.1998.818943 PG 18 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500011 ER PT B AU Baum, CE Farr, EG Frost, CA AF Baum, CE Farr, EG Frost, CA BE Heyman, E Mnadelbaum, B Shiloh, J TI Transient gain of antennas related to the traditional continuous-wave (cw) definition of gain SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL C1 USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. RP Baum, CE (reprint author), USAF, Res Lab, DEHP, Bldg 909,3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 109 EP 118 DI 10.1109/UWBSP.1998.818944 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500012 ER PT B AU Prather, WD Agee, FJ Baum, CE Lehr, JM O'Loughlin, JP Burger, JW Schoenberg, JSH Scholfield, DW Torres, RJ Hull, JP Gaudet, JA AF Prather, WD Agee, FJ Baum, CE Lehr, JM O'Loughlin, JP Burger, JW Schoenberg, JSH Scholfield, DW Torres, RJ Hull, JP Gaudet, JA BE Heyman, E Mnadelbaum, B Shiloh, J TI Ultra-wideband sources and antennas SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Prather, WD (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 51 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 119 EP 130 DI 10.1109/UWBSP.1998.818945 PG 12 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500013 ER PT B AU Baum, CE Stone, AP AF Baum, CE Stone, AP BE Heyman, E Mnadelbaum, B Shiloh, J TI Synthesis of purely dielectric transient lenses SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL C1 USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. RP Baum, CE (reprint author), USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 203 EP 212 DI 10.1109/UWBSP.1998.818954 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500022 ER PT B AU Baum, CE AF Baum, CE BE Heyman, E Mnadelbaum, B Shiloh, J TI Direct construction of a xi-pulse from natural frequencies and evaluation of the late-time residuals SO ULTRA-WIDEBAND SHORT-PULSE ELECTROMAGNETICS 4 LA English DT Proceedings Paper CT 4th International Conference on Ultra-Wideband Short-Pulse Electromagnetics CY JUN 14-19, 1998 CL TEL AVIV, ISRAEL SP Summa Fdn, HPEM Permanent Comm, Yuma Proving Ground, IEEE, URSI, Los Almos Natl Lab, USAF, European Off Aerosp Res & Dev, Maxwell Technologies, Maxwell Phis Int, Minist Sci, Minist Defense, Minist Tourism, RAFAEL C1 USAF, Res Lab, DEHP, Kirtland AFB, NM 87117 USA. RP Baum, CE (reprint author), USAF, Res Lab, DEHP, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46206-0 PY 1999 BP 349 EP 360 DI 10.1109/UWBSP.1998.818968 PG 12 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA BP38L UT WOS:000084929500036 ER PT S AU Shipman, RF Heras, AM Price, SD de Graauw, T Walker, HJ de Muizon, MJ Kessler, MF Prusti, T AF Shipman, RF Heras, AM Price, SD de Graauw, T Walker, HJ de Muizon, MJ Kessler, MF Prusti, T BE Cox, P Kessler, MF TI Classification of silicate emission sources observed with SWS SO UNIVERSE AS SEEN BY ISO, VOLS I AND II SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT Conference on the Universe as Seen by ISO CY OCT 20-23, 1998 CL PARIS, FRANCE SP European Spacy Agcy, Univ Paris, Inst Astrophysique Spatiale, Ctr Nat Etude Spatiale, Alcatel, Arianespace, IPAC, Despa, Observatoire Meudon, REOSC, SAP CEA Saclay DE ISO-SWS; AGBs; CO2 AB We present preliminary results from our effort to classify sources with silicate dust shells observed for the STARTYP1/2 and ZZSTARTY programs. To characterize our silicate sources, we calculate the silicate emission index, SE, developed by Sloan & Price (1995). This index is a quantative description of the shape of the 10 mu m silicate emission feature as seen in the IRAS Low Resolution Spectrometer data of AGE stars. With the larger wavelength coverage and the higher spectral resolution of SWS, we can provide added details to the SE index. In particular, we detect correlations in the strength of the 4.27 mu m CO2 band with the SE classification. The objective of the STARTYP1/2 and ZZSTARTY programs is to construct an ESO database for the spectral classification of the brightest representative sources. The final database will include all sources with full SWS grating scans or PHOT-S observations. C1 USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. RP Shipman, RF (reprint author), USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-708-9 J9 ESA SP PUBL PY 1999 VL 427 BP 401 EP 404 PN 1&2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN74P UT WOS:000082780900084 ER PT S AU Egan, MP Carey, SJ Price, SD Shipman, RF Feldman, P Redman, R AF Egan, MP Carey, SJ Price, SD Shipman, RF Feldman, P Redman, R BE Cox, P Kessler, MF TI The distribution of Galactic IR dark clouds from MSX survey maps SO UNIVERSE AS SEEN BY ISO, VOLS I AND II SE ESA SPECIAL PUBLICATIONS LA English DT Proceedings Paper CT Conference on the Universe as Seen by ISO CY OCT 20-23, 1998 CL PARIS, FRANCE SP European Spacy Agcy, Univ Paris, Inst Astrophysique Spatiale, Ctr Nat Etude Spatiale, Alcatel, Arianespace, IPAC, Despa, Observatoire Meudon, REOSC, SAP CEA Saclay DE ISM : clouds; IR : surveys AB In quadrants I and IV of the Milky Way we have detected > 5000 Infrared Dark Clouds (IRDCs) using the MSX Galactic Plane Survey images at 8 mu m. Follow-up observations of a sample of the IRDCs in the millimeter-wave and sub-millimeter regions of the spectrum confirm initial estimates of the high density (> 10(5) cm(-3)) and low temperature (similar to 10 K) of the clouds. The distribution of the clouds maps known structures in the Galaxy (spiral arm tangents, the molecular ring). C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Egan, MP (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 4 TC 6 Z9 6 U1 0 U2 0 PU EUROPEAN SPACE AGENCY PI PARIS PA 8-10 RUE MARIO NIKIS, 75738 PARIS, FRANCE SN 0379-6566 BN 92-9092-708-9 J9 ESA SP PUBL PY 1999 VL 427 BP 671 EP 674 PN 1&2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA BN74P UT WOS:000082780900135 ER PT S AU Lindsey, AR Suter, BW AF Lindsey, AR Suter, BW BE Szu, HH TI Convolution theorems: Partitioning the space of integral transforms SO WAVELET APPLICATIONS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Wavelet Applications VI CY APR 06-08, 1999 CL ORLANDO, FL SP Soc Photo Opt Instrumentat Engineers AB Investigating a number of different integral transforms uncovers distinct patterns in the type of translation convolution theorems afforded by each. It is shown that transforms based on separable kernels (aka Fourier, Laplace and their relatives) have a form of the convolution theorem providing for a transform domain product of the convolved functions. :However, transforms based on kernels not separable in the function and transform variables mandate a convolution theorem of a different type; namely in the transform domain the convolution becomes another convolution - one function with the transform of the other. C1 USAF, Res Lab, IFGC, Griffiss AFB, NY 13441 USA. RP Lindsey, AR (reprint author), USAF, Res Lab, IFGC, 525 Brooks Rd, Griffiss AFB, NY 13441 USA. NR 10 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 0-8194-3197-4 J9 P SOC PHOTO-OPT INS PY 1999 VL 3723 BP 277 EP 285 DI 10.1117/12.342937 PG 9 WC Engineering, Electrical & Electronic; Remote Sensing; Optics SC Engineering; Remote Sensing; Optics GA BM94B UT WOS:000080194100027 ER PT S AU Evwaraye, AO Smith, SR Mitchel, WC AF Evwaraye, AO Smith, SR Mitchel, WC BE Binari, SC Burk, AA Melloch, MR Nguyen, C TI The comparative studies of chemical vapor deposition grown epitaxial layers and of sublimation sandwich method grown 4H-SiC samples SO WIDE-BANDGAP SEMICONDUCTORS FOR HIGH-POWER, HIGH-FREQUENCY AND HIGH-TEMPERATURE APPLICATIONS-1999 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Wide-Bandgap Semiconductors for High-Power, High-Frequency and High-Temperature Applications-1999 at the 1999 MRS Spring Meeting CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Air Force Res Labs, DARPA, ODDR&E(R), Army Res Off ID ADMITTANCE SPECTROSCOPY; SHALLOW; CARBIDE AB Thermal admittance spectroscopy was used to characterize the shallow dopants in chemical vapor deposition( CVD) grown thin films and in sublimation sandwich method (SIM) grown 4H-SiC layers. The values of the activation energy levels of E-C - 0.054 eV for Nitrogen at the hexagonal site and of E-C - 0.10 eV for Nitrogen at the cubic site were indices of comparison. The net carrier concentrations ( N-D - N-V) of the films were determined by capacitance-voltage measurements. The net carrier concentrations for the SSM films ranged from 2 x 10(17) to 7 x 10(17) cm(-3). The two Nitrogen levels were observed in the CVD films. Hopping conduction with an activation energy of E-C - 0.0058 eV was observed in one SSM sample having N-D - N-V = 7 x 10(17) cm(-3). C1 USAF, Res Lab, MLPO, Mat Directorate, Wright Patterson AFB, OH 45422 USA. RP Evwaraye, AO (reprint author), USAF, Res Lab, MLPO, Mat Directorate, Wright Patterson AFB, OH 45422 USA. NR 7 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 1-55899-479-3 J9 MATER RES SOC SYMP P PY 1999 VL 572 BP 237 EP 242 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA BN81E UT WOS:000083014400037 ER PT S AU Smith, SR Evwaraye, AO Mitchel, WC Solomon, JS Goldstein, J AF Smith, SR Evwaraye, AO Mitchel, WC Solomon, JS Goldstein, J BE Binari, SC Burk, AA Melloch, MR Nguyen, C TI Characterization of vanadium-doped 4H-SiC using optical admittance spectroscopy SO WIDE-BANDGAP SEMICONDUCTORS FOR HIGH-POWER, HIGH-FREQUENCY AND HIGH-TEMPERATURE APPLICATIONS-1999 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Wide-Bandgap Semiconductors for High-Power, High-Frequency and High-Temperature Applications-1999 at the 1999 MRS Spring Meeting CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Air Force Res Labs, DARPA, ODDR&E(R), Army Res Off ID SILICON-CARBIDE; DEFECTS AB Vanadium is an important dopant in SiC because it fives rise to donor levels near the middle of the bandgap which can be used to make the material semi-insulating, and semiinsulating material has many applications as a substrate material for high-power electronics. However, conventional means of characterizing electronic levels in the bandgap of the material require very high temperatures, in the neighborhood of 650-800 degrees C, in order to move the Fermi level to midgap and cause ionization of the V donors. The technique of Optical Admittance Spectroscopy permits the ionization of the midgap donors using light of the appropriate energy, and thus avoids the need for high temperatures. Using this technique we have examined several specimens of V-doped and high-resistivity 4H-SiC. We have identified levels previously associated with V, and new levels we attribute to Ti. Pinning of the Fermi level in some specimens was verified by high-temperature Hall effect measurements. SIMS measurements were used to determine impurity concentrations. IR absorption measurements were correlated with the Ti, V, and Cr concentrations determined by SIMS. C1 USAF, Res Lab, MLPO, Mat Directorate, Wright Patterson AFB, OH 45422 USA. RP Smith, SR (reprint author), USAF, Res Lab, MLPO, Mat Directorate, Wright Patterson AFB, OH 45422 USA. NR 7 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 1-55899-479-3 J9 MATER RES SOC SYMP P PY 1999 VL 572 BP 253 EP 258 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA BN81E UT WOS:000083014400039 ER PT S AU Linville, RJ Brown, GJ Mitchell, WC Saxler, A Perrin, R AF Linville, RJ Brown, GJ Mitchell, WC Saxler, A Perrin, R BE Binari, SC Burk, AA Melloch, MR Nguyen, C TI Mid infrared photoconductivity spectra of donor impurities in hexagonal silicon carbide SO WIDE-BANDGAP SEMICONDUCTORS FOR HIGH-POWER, HIGH-FREQUENCY AND HIGH-TEMPERATURE APPLICATIONS-1999 SE MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS LA English DT Proceedings Paper CT Symposium on Wide-Bandgap Semiconductors for High-Power, High-Frequency and High-Temperature Applications-1999 at the 1999 MRS Spring Meeting CY APR 05-08, 1999 CL SAN FRANCISCO, CA SP Mat Res Soc, Air Force Res Labs, DARPA, ODDR&E(R), Army Res Off AB Mid-infrared photoconductivity (PC) is a useful technique for identifying and investigating donor and acceptor centers in many semiconductors. This is especially true when the PC results are combined with other measurements such as Hall Effect and DLTS. We report on the first Fourier Transform Infrared (FTIR) photoconductivity spectra for n-type 6H and 4H-SiC. The samples studied had temperature dependent Hall activation energies around 45 meV and 85 meV in the 4H samples, and a single activation energy of 106 meV in the 6H. For the 4H samples, the PC spectra showed an increase in photoresponse between 40 and 47 meV, with another sharp increase at 120 meV. In the 6H-SiC, the photoresponse also had a rapid increase at 120 meV, and at 77 meV in one sample. The photoresponse spectra of the n-type 4H and 6H-SiC samples were distinctly different in the mid-infrared. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL MLPO, Wright Patterson AFB, OH USA. RP Linville, RJ (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL MLPO, 3005 P ST, Wright Patterson AFB, OH USA. NR 5 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 1-55899-479-3 J9 MATER RES SOC SYMP P PY 1999 VL 572 BP 281 EP 286 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA BN81E UT WOS:000083014400044 ER PT B AU Pettit, CL Jones, NP Ghanem, R AF Pettit, CL Jones, NP Ghanem, R BE Larsen, A Larose, GL Livesey, FM TI Detection, analysis and simulation of roof-corner pressure transients SO WIND ENGINEERING INTO THE 21ST CENTURY, VOLS 1-3 LA English DT Proceedings Paper CT 10th International Conference on Wind Engineering (10ICWE) CY JUN 21-24, 1999 CL COPENHAGEN, DENMARK SP Danish Maritime Inst, COWI Consulting Engineers & Planners, Monberg & Thorsen A S, Kobenhavns Kommune, Scandinavian Airlines Syst, Danish Tech Res Council, Dantec A S, MSC Nordic, COWI Fdn AB Many practical time series, including some pressure signals measured on roof-corners of low-rise buildings in quartering winds, consist of relatively quiescent periods interrupted by transients. In this paper, the dyadic wavelet transform is used to detect these transients in pressure time series. A relatively simple pattern classification scheme is then used detect the underlying structure in these transients. Statistical analysis of the resulting pattern classes yielded a library of signal "building blocks", which are useful for detailed characterization of transients inherent to the signals being analyzed. Nonparametric probability density functions computed for various pattern features and arrival intervals were sampled to generate synthetic time series that mimic the intermittency and transient magnitudes of the original time series. C1 USAF, RL, VASD, Wright Patterson AFB, OH 45433 USA. RP Pettit, CL (reprint author), USAF, RL, VASD, Wright Patterson AFB, OH 45433 USA. RI Jones, Nicholas/A-2328-2010 NR 10 TC 0 Z9 0 U1 0 U2 0 PU A A BALKEMA PUBLISHERS PI LEIDEN PA SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS BN 90-5809-059-0 PY 1999 BP 1831 EP 1838 PG 8 WC Construction & Building Technology; Energy & Fuels; Engineering, Civil SC Construction & Building Technology; Energy & Fuels; Engineering GA BN41H UT WOS:000081857400254 ER PT S AU Ondercin, RJ Goldman, LM Harker, AB AF Ondercin, RJ Goldman, LM Harker, AB BE Tustison, RW TI Development of a repairable IR composite window SO WINDOW AND DOME TECHNOLOGIES AND MATERIALS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 6th Conference on Window and Dome Technologies and Materials CY APR 05-06, 1999 CL ORLANDO, FL SP SPIE AB Infrared (IR) imaging systems are a critical component of military aircraft operations for navigation, surveillance, and target acquisition. A limiting feature in the readiness and life-cycle costs for such IR systems is the durability of the exposed optical window in the harsh land and sea environments associated with military operations. The Air Force Research Laboratory, Materials Directorate, has been conducting a program to develop a high durability, repairable IR window to both extend the operation life-cycle of the transparencies and to permit the reuse of the optical materials for significant cost reductions. The development effort is focused on a composite IR window composed of a highly IR transparent base material with a removable durable bonded cladding for erosion and abrasion protection. The development activities have included evaluation and selection of the optical materials, assessment of high durability coatings, refinement of the optical adhesive and bonding process, as well as laboratory and flight testing. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Ondercin, RJ (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 7 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 0-8194-3179-6 J9 P SOC PHOTO-OPT INS PY 1999 VL 3705 BP 238 EP 249 DI 10.1117/12.354628 PG 12 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Optics SC Engineering; Materials Science; Optics GA BN69W UT WOS:000082635600027 ER PT J AU Elston, DM AF Elston, DM TI Perinatal transmission of human granulocytic ehrlichiosis SO NEW ENGLAND JOURNAL OF MEDICINE LA English DT Letter ID LYME-DISEASE; PREVENTION C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78148 USA. RP Elston, DM (reprint author), Wilford Hall USAF Med Ctr, Lackland AFB, TX 78148 USA. NR 7 TC 6 Z9 6 U1 0 U2 0 PU MASSACHUSETTS MEDICAL SOC PI WALTHAM PA WALTHAM WOODS CENTER, 860 WINTER ST,, WALTHAM, MA 02451-1413 USA SN 0028-4793 J9 NEW ENGL J MED JI N. Engl. J. Med. PD DEC 24 PY 1998 VL 339 IS 26 BP 1941 EP 1942 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 150ZN UT WOS:000077696600018 PM 9874610 ER PT J AU Fuchs, F Ahlswede, E Weimar, U Pletschen, W Schmitz, J Hartung, M Jager, B Szmulowicz, F AF Fuchs, F Ahlswede, E Weimar, U Pletschen, W Schmitz, J Hartung, M Jager, B Szmulowicz, F TI Magneto-optics of InAs/Ga1-xInxSb infrared superlattice diodes SO APPLIED PHYSICS LETTERS LA English DT Article ID ENVELOPE-FUNCTION APPROXIMATION; PHOTODIODES AB Spectrally resolved measurements of the responsivity of infrared photodiodes based on InAs/(GaIn)Sb superlattices (SL) were performed in applied magnetic fields. For the field oriented parallel to the growth axis, interband Landau transitions related to both the center and the edge of the SL Brillouin zone in the growth direction were observed, in accordance with the parity selection rules that are expected for the type II system under consideration. For the field oriented perpendicular to the growth axis, the interband Landau resonances are broadened and the widening of the band gap is smaller. (C) 1998 American Institute of Physics. [S0003-6951(98)04751-2]. C1 Fraunhofer Inst Angew Festkorperphys, D-79108 Freiburg, Germany. Univ Munich, Sekt Phys, D-80539 Munich, Germany. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Fuchs, F (reprint author), Fraunhofer Inst Angew Festkorperphys, Tullastr 72, D-79108 Freiburg, Germany. NR 16 TC 17 Z9 17 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 21 PY 1998 VL 73 IS 25 BP 3760 EP 3762 DI 10.1063/1.122886 PG 3 WC Physics, Applied SC Physics GA 146XH UT WOS:000077458200045 ER PT J AU Varangis, PM Gavrielides, A Kovanis, V Lester, LF AF Varangis, PM Gavrielides, A Kovanis, V Lester, LF TI Linewidth broadening across a dynamical instability SO PHYSICS LETTERS A LA English DT Article DE semiconductor laser; noise; linewidth; bifurcation ID MODE SEMICONDUCTOR-LASERS; COHERENCE COLLAPSE; OPTICAL-INJECTION; FREQUENCY; NOISE; FEEDBACK AB We investigate experimentally and theoretically the variation of the emission linewidth of an optically-injected semiconductor laser across a resonant period-doubling bifurcation. Close to the dynamical instability, the intrinsic and external phase fluctuations are amplified, resulting in a spectral linewidth in excess of that accounted for by the spontaneous-emission process alone. (C) 1998 Elsevier Science B.V. C1 USAF, Res Lab, DELO, Kirtland AFB, NM 87117 USA. Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. RP Varangis, PM (reprint author), USAF, Res Lab, DELO, Kirtland AFB, NM 87117 USA. NR 26 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD DEC 21 PY 1998 VL 250 IS 1-3 BP 117 EP 122 DI 10.1016/S0375-9601(98)00830-5 PG 6 WC Physics, Multidisciplinary SC Physics GA 152ZH UT WOS:000077807800020 ER PT J AU Whiteley, MR Welsh, BM Roggemann, MC AF Whiteley, MR Welsh, BM Roggemann, MC TI Incorporating higher-order modal measurements in tilt estimation: natural and laser guide star applications SO APPLIED OPTICS LA English DT Article ID FULL APERTURE TILT; PHASE-EXPANSION COEFFICIENTS; ATMOSPHERIC-TURBULENCE; ZERNIKE POLYNOMIALS; ADAPTIVE OPTICS; SPATIAL CORRELATION; COMPENSATION; TELESCOPES; DISTORTION; ANISOPLANATISM 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. We apply optimal compensation theory to tilt correction for the case of an off-axis beacon. Because 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, although tilt information cannot be measured directly because of 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 the relative aperture diameter D/r(o) = 4 and the relative turbulence outer scale L-o/D = 10. (C) 1998 Optical Society of America. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. Michigan Technol Univ, Dept Elect Engn, Houghton, MI 49931 USA. RP Whiteley, MR (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 38 TC 6 Z9 6 U1 1 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 20 PY 1998 VL 37 IS 36 BP 8287 EP 8296 DI 10.1364/AO.37.008287 PG 10 WC Optics SC Optics GA 150XA UT WOS:000077690300001 PM 18301651 ER PT J AU Smith, PR Gambone, ML Williams, DS Garner, DI AF Smith, PR Gambone, ML Williams, DS Garner, DI TI Heat treatment effects on SiC fiber SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID MICROSTRUCTURE; COMPOSITES AB The Wright Laboratory Materials Directorate at Wright-Patterson AFB has been spearheading the development and evaluation of a new class of metal matrix composites based upon continuous SIC fiber reinforcement of orthorhombic phase containing titanium aluminide matrices. These composites (O TMCs) will be subjected to thermal exposures during primary and secondary component processing, and possibly also during heat treatments to optimize matrix-dominated mechanical performance. Such thermal excursions must not degrade the SIC fiber reinforcement, hence compromising resulting composite properties. Therefore, the effects of heat treatment on the room temperature tensile strength of continuous SIC fibers were studied. The fibers examined included: Trimarc 1(R), SCS-6, Ultra SCS and an experimental large diameter version of Ultra SCS. The fibers were heat treated below and above the beta solvus temperature of the orthorhombic matrix alloy utilized for this study, Ti-22Al-23Nb (at %). The fibers were evaluated for ambient temperature tensile strength in the following conditions: (1) as-received: (2) heat treated in vacuum; and (3) consolidated into Ti-22Al-23Nb, heat treated in vacuum, and chemically extracted. Fiber microstructure and fracture analysis was accomplished via secondary scanning electron microscopy (SEM). Chemical reactions between fiber core and the SiC, and between the SiC fiber and the Ti-22Al-23Nb matrix, were also studied by SEM. (C) 1998 Kluwer Academic Publishers. C1 WL MLLM, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. SOCHE, Dayton, OH 45420 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP WL MLLM, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 20 TC 19 Z9 21 U1 0 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2461 EI 1573-4803 J9 J MATER SCI JI J. Mater. Sci. PD DEC 15 PY 1998 VL 33 IS 24 BP 5855 EP 5872 DI 10.1023/A:1004478804694 PG 18 WC Materials Science, Multidisciplinary SC Materials Science GA 170YG UT WOS:000078834300018 ER PT J AU Feng, L Tang, J Zabinski, JS AF Feng, L Tang, J Zabinski, JS TI Tribological properties of magnetron-sputtered TiC coatings SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE coatings; multilayers; titanium carbide; tribology ID PULSED-LASER DEPOSITION; TITANIUM CARBIDE; PARAMETERS; WEAR AB Tribological properties, including friction, wear, and hardness, as well as microstructure, have been investigated using a pin-on-disk configuration for TIC coatings with different kinds of interlayers (Ti, Cr and Mo) of different thicknesses. Both stainless steel and alumina pins were alternately used. The wear tracks and cross-section microstructure of the TiC coatings with different interlayers were further characterized by optical microscopy or scanning electron microscopy (SEM). It is found that inserting a Cr or Ti interlayer between the coatings and substrates improves the friction, wear, hardness, and elastic modulus of the coatings, but inserting a Mo interlayer had the opposite effect. The influence of different kinds of interlayers, their thickness, as well as the TiC coating thickness on the tribological properties of the coatings are discussed. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ New Orleans, Dept Phys, New Orleans, LA 70148 USA. USAF, Wright Lab, MLBT, Wright Patterson AFB, OH 45433 USA. RP Tang, J (reprint author), Univ New Orleans, Dept Phys, New Orleans, LA 70148 USA. EM jtang@uno.edu NR 14 TC 6 Z9 6 U1 1 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 15 PY 1998 VL 257 IS 2 BP 240 EP 249 DI 10.1016/S0921-5093(98)00859-4 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 149ZC UT WOS:000077636200004 ER PT J AU Shahriar, MS Hemmer, PR AF Shahriar, MS Hemmer, PR TI Generation of squeezed states and twin beams via non-degenerate four-wave mixing in a Lambda system SO OPTICS COMMUNICATIONS LA English DT Article DE Lambda system; non-degenerate four-wave mixing; quantum phase noise ID OPTICAL-PHASE CONJUGATION; NOISE; EFFICIENT; SODIUM; VAPOR; LIGHT; LIMIT AB We show that non-degenerate four-wave mixing in a Lambda system yields strong suppression of quantum phase noise when the probe and conjugate beams are monitored via balanced homodyne detection. Unlike previous calculations performed on similar system, we include situations where the pump beams become resonant with the corresponding two-level transitions. As a result, we find conditions wherein strong squeezing can be achieved with relatively low pump powers. Furthermore, we show explicitly, via numerical integration, that the probe and the conjugate beams, each starting from the vacuum, are twin beams, containing matching number of photons. The low-power, high gain phase conjugation observed experimentally by us in rubidium vapor under similar conditions indicate the feasibility of realizing a spatially broad band source of squeezed light, with applications to fast detection of faint images, as well as to high-density optical interconnects. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 MIT, Elect Res Lab, Cambridge, MA 02139 USA. USAF, Res Lab, Hanscom Air Force Base, Bedford, MA 01731 USA. RP Shahriar, MS (reprint author), MIT, Elect Res Lab, Cambridge, MA 02139 USA. RI Shahriar, Selim/B-7270-2009 NR 22 TC 13 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD DEC 15 PY 1998 VL 158 IS 1-6 BP 273 EP 286 DI 10.1016/S0030-4018(98)00528-8 PG 14 WC Optics SC Optics GA 152AH UT WOS:000077752700038 ER PT J AU Chu, J Li, SS Singh, A AF Chu, J Li, SS Singh, A TI Investigation of broadband p-type quantum-well infrared photodetectors SO APPLIED PHYSICS LETTERS LA English DT Article ID EPITAXIAL MULTILAYERS; DEFECTS; DISLOCATIONS AB Typical quantum-well infrared photodetectors (QWIPs) exhibit rather narrow spectral bandwidths of 1-2 mu m. For certain applications, such as spectroscopy, sensing of a broad range of infrared photons is necessary. In this letter, we report on the design of two p-type broadband (BB) QWIPs for detection in the 7-14 mu m long-wavelength infrared band. Two different QWIP structures were designed: QWIP-A with three wells of different InxGa1-xAs(x = 0.2, 0.25, 0.3) compositions and QWIP-B with three wells of In0.25Ga0.75As of different thicknesses (4.5, 5.5, and 6.2 nm) and an undoped GaAs barrier (40 nm thick) to form a unit cell, which are then repeated 20 times to create the BB-QWIPs. The spectral response for QWIP-A covers the wavelengths from the 7 to 11 mu m range, while QWIP-B has a broader spectral response bandwidth from 7 to 14 mu m. A maximum responsivity of 25 mA/W was obtained for QWIP-B at V-b = 1.1 V, lambda(p) = 10.2 mu m, and T = 40 K with a spectral bandwidth of Delta lambda/lambda = 63%, a cut-on wavelength at 6.2 mu m, and a cut-off wavelength around 14 mu m. (C) 1998 American Institute of Physics. [S0003-6951(98)04249-1]. C1 Univ Florida, Dept Elect & Comp Engn, Gainesville, FL 32611 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Chu, J (reprint author), Univ Florida, Dept Elect & Comp Engn, Gainesville, FL 32611 USA. NR 13 TC 3 Z9 3 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 7 PY 1998 VL 73 IS 23 BP 3414 EP 3416 DI 10.1063/1.122782 PG 3 WC Physics, Applied SC Physics GA 146MJ UT WOS:000077432600032 ER PT J AU Takekoshi, T Patterson, BM Knize, RJ AF Takekoshi, T Patterson, BM Knize, RJ TI Observation of optically trapped cold cesium molecules SO PHYSICAL REVIEW LETTERS LA English DT Article ID STARK SHIFT; ATOMS; IONIZATION; CO2-LASER AB We report the first observation of optically trapped cold neutral molecules. Cesium dimers in the electronic ground state are produced directly in a magneto-optical trap and transferred to a dipole trap formed at the focus of a CO2 laser beam (lambda - 10.6 mu m). These neutral molecules were detected using photoionization and time-of-flight spectroscopy. Initial experiments indicate a cold molecule trap lifetime on the order of half a second. [S0031-9007(98)07817-X]. C1 USAF Acad, Dept Phys, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. RP Takekoshi, T (reprint author), USAF Acad, Dept Phys, Laser & Opt Res Ctr, Colorado Springs, CO 80840 USA. NR 25 TC 196 Z9 198 U1 2 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 7 PY 1998 VL 81 IS 23 BP 5105 EP 5108 DI 10.1103/PhysRevLett.81.5105 PG 4 WC Physics, Multidisciplinary SC Physics GA 145GH UT WOS:000077362300017 ER PT J AU Day, PN Wang, ZQ Pachter, R AF Day, PN Wang, ZQ Pachter, R TI Calculation of the structure and absorption spectra of phthalocyanines in the gas-phase and in solution SO THEOCHEM-JOURNAL OF MOLECULAR STRUCTURE LA English DT Article DE phthalocyanines; visible spectra; vibrational spectra; solvation effects ID MOLECULAR-ORBITAL METHODS; REVERSE SATURABLE ABSORPTION; COMPACT EFFECTIVE POTENTIALS; REACTION-FIELD METHOD; EXPONENT BASIS-SETS; GAUSSIAN-TYPE BASIS; ELECTRONIC-STRUCTURE; ORGANIC-MOLECULES; SPECTROSCOPY; EFFICIENT AB Ab initio calculations have been carried out on both gas-phase and solvated phthalocyanines in order to determine equilibrium structures, vibrational spectra, and electronic spectra. Density functional theory (DFT) optimized geometries have the expected symmetries of D-2h for free-base phthalocyanine, D-4h for copper phthalocyanine, and C-4v for tin phthalocyanine, whereas Hartree-Fock optimized geometries, which also include lead phthalocyanine, are slightly displaced from the expected symmetries. Both sets of optimized geometries agree reasonably well with the available experimental structures. Vibrational spectra, calculated by the Hartree-Fock method, are in partial agreement with measured spectra, whereas visible absorption spectra calculated using molecular geometries obtained at three different levels of theory (DFT, HF, and PM3) showed good agreement with the measured vapor-phase spectra in the Q-band, and using the DFT optimized geometry resulted in very good agreement with measurements in the B-band. The self-consistent reaction held method for including bulk solvent effects in HF calculations had a small, nearly negligible, effect on the molecular structure of SnPc, whereas the DFT/COSMO solvation model yielded the predictable result of increasing the Sn-N bond length by pulling the Sn atom further out of the molecular plane. (C) 1998 Elsevier Science B.V. All rights reserved. C1 USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Pachter, R (reprint author), USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 37 TC 74 Z9 74 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 THEOCHEM-J MOL STRUC JI Theochem-J. Mol. Struct. PD DEC 4 PY 1998 VL 455 IS 1 BP 33 EP 50 DI 10.1016/S0166-1280(98)00238-3 PG 18 WC Chemistry, Physical SC Chemistry GA 146PP UT WOS:000077439800004 ER PT J AU Schwartz, M Marshall, P Berry, RJ Ehlers, CJ Petersson, GA AF Schwartz, M Marshall, P Berry, RJ Ehlers, CJ Petersson, GA TI Computational study of the kinetics of hydrogen abstraction from fluoromethanes by the hydroxyl radical SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID TRANSITION-STATE THEORY; GAUSSIAN-2 THEORY; RATE CONSTANTS; TUNNELING CALCULATIONS; SUBSTITUTED METHANES; RATE COEFFICIENTS; OH; ABINITIO; CH4; ENERGIES AB One of the fastest steps in the initial decomposition of HFCs under combustion conditions is hydrogen atom abstraction by hydroxyl radicals. We have utilized ab initio quantum mechanics and transition-state theory (TST) to calculate the temperature dependence of rate constants for the reactions of OH with CH4, CH3F, CH2F2, and CHF3. Rate constants calculated using HF/6-31G(d) frequencies and MP2(full)/6-31G(d) structures to evaluate reactant and transition-state partition functions and the Hartree-Fock imaginary frequency, wi, to compute Eckart tunneling factors, Gamma, yielded rate constants that were substantially greater than experiment. Adjustment of the energy barrier to effect agreement between experimental and calculated rate constants at 298 K gave Arrhenius plots that exhibited markedly greater curvature than measured rate constants. When the imaginary frequency and barrier height were calculated by fitting high-level (G2) energies along the reaction path with a semiempirical Eckart function, it was found that the calculated imaginary frequency is a factor of 2.5 lower than the HF/6-31G(d) value, indicating that the energy barrier is considerably broader than predicted by the latter frequency. When the new imaginary frequencies and barrier heights were used to calculate rate constants, it was found that k(TST) < k(expt) but that lowering the barrier height (by an average of 4.7 kJ/mol for the four reactions) yields calculated rate constants that are in excellent agreement with experiment at all temperatures. C1 Univ N Texas, Dept Chem, Denton, TX 76203 USA. USAF, Ctr Computat Modeling Res Nonstruct Mat, Res Lab, Wright Patterson AFB, OH 45433 USA. Wesleyan Univ, Hall Atwater Labs Chem, Middletown, CT 06459 USA. RP Schwartz, M (reprint author), Univ N Texas, Dept Chem, Denton, TX 76203 USA. NR 41 TC 69 Z9 71 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD DEC 3 PY 1998 VL 102 IS 49 BP 10074 EP 10081 DI 10.1021/jp9822891 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 146ZX UT WOS:000077464700011 ER PT J AU Baur, JW Kim, S Balanda, PB Reynolds, JR Rubner, MF AF Baur, JW Kim, S Balanda, PB Reynolds, JR Rubner, MF TI Thin-film light-emitting devices based on sequentially adsorbed multilayers of water-soluble poly(p-phenylene)s SO ADVANCED MATERIALS LA English DT Article ID ULTRATHIN FILMS; POLYMERS; DIODES; HETEROSTRUCTURES; POLYELECTROLYTES C1 MIT, Dept Mat Sci & Engn, Cambridge, MA 02145 USA. AFRL, MLBP, Polymer Res Branch, Wright Patterson AFB, OH 45433 USA. Univ Florida, Dept Chem, Ctr Macromol Sci & Engn, Gainesville, FL 32611 USA. RP Rubner, MF (reprint author), MIT, Dept Mat Sci & Engn, Cambridge, MA 02145 USA. NR 28 TC 119 Z9 121 U1 1 U2 9 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0935-9648 J9 ADV MATER JI Adv. Mater. PD DEC 1 PY 1998 VL 10 IS 17 BP 1452 EP 1455 DI 10.1002/(SICI)1521-4095(199812)10:17<1452::AID-ADMA1452>3.0.CO;2-V PG 4 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 147CN UT WOS:000077470500008 ER PT J AU Turcotte, JS Hollkamp, JJ Gordon, RW AF Turcotte, JS Hollkamp, JJ Gordon, RW TI Vibration of a mistimed bladed-disk assembly using structurally damped beams SO AIAA JOURNAL LA English DT Article AB A model of a mistuned bladed disk is created and then analyzed for both free and forced vibrations. The model consists of structurally damped, Euler-Bernoulli beams connected at one end using springs, The model is useful in the prediction of the response of a turbine engine bladed disk in which only some of the blades have added damping. (This situation arises in the experimental analysis of damping treatments.) The natural frequencies and eigenfunction sets are obtained by assuming harmonic motion and imposing the boundary conditions. The eigensolution was verified using a small NASTRAN model. The forced response due to phased, harmonic tip loads is obtained by modalizing the equations using a technique recently developed by Turcotte (Turcotte, J, S., "An Analytical Model for the Forced Response of Cyclic Structures," Journal of Sound and Vibration, Vol, 209, No. 3, 1.998, pp, 531-536), The physical response is obtained as a function of forcing frequency by truncation and summation of the modal responses. The results are in general agreement with those of existing discrete models but have much greater detail. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Air Vehicle Directorate, Wright Patterson AFB, OH 45433 USA. RP Turcotte, JS (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 4 TC 7 Z9 8 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1998 VL 36 IS 12 BP 2225 EP 2228 DI 10.2514/2.330 PG 4 WC Engineering, Aerospace SC Engineering GA 148KK UT WOS:000077503900010 ER PT J AU Cina, SJ Li, DJ Chan, DW Boitnott, JK Hruban, RH Smialek, JE AF Cina, SJ Li, DJ Chan, DW Boitnott, JK Hruban, RH Smialek, JE TI Serum concentrations of cardiac troponin I in sudden death - A pilot study SO AMERICAN JOURNAL OF FORENSIC MEDICINE AND PATHOLOGY LA English DT Article DE death; troponin; ischemia; autopsy; sudden death; cardiac troponin I; creatine kinase MB; heart; infarct ID ACUTE MYOCARDIAL-INFARCTION; PROGNOSTIC VALUE; DIAGNOSIS; IMMUNOASSAY AB Sudden cardiac death due to lethal arrhythmia may be the initial presenting symptom of ischemic heart disease. In many cases, in the absence of trauma, a majority of these deaths will be visually inspected by a medical examiner and released with death being ascribed to atherosclerotic cardiovascular disease, coronary artery disease, arrhythmia, myocardial infarction, or a similar diagnosis. When an autopsy is performed, there may be significant cardiovascular disease but no gross or histologic evidence of an acute myocardial infarct unless the patient survived for several hours following the event. Biochemical assays of creatine kinase MB fraction (CKMB) performed on serum have been used to document myocardial injury in the absence of morphologic changes. Newly developed assays for cardiac troponin I (cTnI) may detect myocardial injury with a greater sensitivity than CKMB. A prospective study was performed on 28 autopsied patients at the Office of the Chief Medical Examiner of the state of Maryland. Subclavian blood was sampled for subsequent analysis of serum CKMB and cTnI. In 3 cases of cardiac-related death, there was insufficient plasma for analysis of both CKMB and cTnI, and only CKMB was quantitated. In 12 cases, hemolysis rendered interpretation questionable. Of the remaining 16 cases, the mean serum CKMB level was 857.9 ng/ml (n = 7) and the cTnI level was 93.4 ng/ml (n = 3) for cardiac-related deaths, compared with mean CKMB levels of 116.3 ng/ml (n = 9) and mean cTnI levels of 16.6 ng/ml (n = 9) for non-cardiac-related deaths. The differences in serum elevation of both CKMB and cTnI noted between the cardiac- and non-cardiac-related deaths were statistically significant. Serum cTnI concentrations >40 ng/ml were only noted in cardiac-related deaths. These data suggest that an elevated postmortem serum concentration of cTnI reflects ischemic heart disease and supports its use in determining cause of death. Quantitation of this analyte may prove useful when death may be due to an arrhythmia following a morphologically undetectable microinfarct. C1 Wilford Hall USAF Med Ctr, Dept Pathol, Lackland AFB, TX 78236 USA. RP Cina, SJ (reprint author), Wilford Hall USAF Med Ctr, Dept Pathol, Lackland AFB, TX 78236 USA. NR 17 TC 24 Z9 26 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-7910 J9 AM J FOREN MED PATH JI Am. J. Forensic Med. Pathol. PD DEC PY 1998 VL 19 IS 4 BP 324 EP 328 DI 10.1097/00000433-199812000-00006 PG 5 WC Medicine, Legal; Pathology SC Legal Medicine; Pathology GA 154RF UT WOS:000077902000006 PM 9885925 ER PT J AU De Jong, MJ AF De Jong, MJ TI Hyponatremia - A life-threatening complication of the widely used thiazide diuretics. SO AMERICAN JOURNAL OF NURSING LA English DT Article C1 Wilford Hall USAF Med Ctr, Coronary Care Unit, San Antonio, TX 78236 USA. RP De Jong, MJ (reprint author), Wilford Hall USAF Med Ctr, Coronary Care Unit, 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 0002-936X J9 AM J NURS JI Am. J. Nurs. PD DEC PY 1998 VL 98 IS 12 BP 36 EP 36 PG 1 WC Nursing SC Nursing GA 145QB UT WOS:000077381900022 PM 9875180 ER PT J AU Steele, A Mallipeddi, P Welgoss, J Soled, S Kohli, N Karram, M AF Steele, A Mallipeddi, P Welgoss, J Soled, S Kohli, N Karram, M TI Teaching the pelvic organ prolapse quantitation system SO AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY LA English DT Article; Proceedings Paper CT 24th Scientific Meeting of the Society-of-Gynecologic-Surgeons CY MAR 02-04, 1998 CL LAKE BUENA VISTA, FLORIDA SP Soc Gynecol Surgeons DE education; prolapse; quantitation ID RESIDENTS; SKILLS AB OBJECTIVE: The objective of this study was to determine the ease with which the new Pelvic Organ Prolapse Quantitation system could be teamed by residents and medical students. STUDY DESIGN: Standardized multiple-choice tests were administered to 51 obstetric and gynecology residents and medical students from 4 community-based and university-based programs. Parallel pretests and posttests were administered in conjunction with a 17-minute video demonstration of the Pelvic Organ Prolapse Quantitation system and with the addition of a visual memory aid. The posttest was repeated 3 months after the video presentation. RESULTS: The use of a 17-minute video significantly enhanced participants' ability to interpret examination findings when expressed in the terminology of the system (mean improvement in scores 33%, P <.0001). Posttest scores were similar regardless of the type of program or exposure to urogynecology faculty. These scores were maintained at the 3-month retesting. CONCLUSION: The Pelvic Organ Prolapse Quantitation system can be effectively taught by means of a public-domain video presentation. C1 Good Samaritan Hosp, Seton Ctr Adv Obstet & Gynecol, Div Urogynecol, Cincinnati, OH 45220 USA. Good Samaritan Hosp, Seton Ctr Adv Obstet & Gynecol, Div Reconstruct Pelv Surg, Cincinnati, OH 45220 USA. Ohio State Univ, Columbus, OH 43210 USA. USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. Univ Cincinnati, Coll Educ, Cincinnati, OH 45221 USA. RP Steele, A (reprint author), Good Samaritan Hosp, Seton Ctr Adv Obstet & Gynecol, Div Urogynecol, Cincinnati, OH 45220 USA. NR 13 TC 18 Z9 20 U1 0 U2 0 PU MOSBY-YEAR BOOK INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0002-9378 J9 AM J OBSTET GYNECOL JI Am. J. Obstet. Gynecol. PD DEC PY 1998 VL 179 IS 6 BP 1458 EP 1463 DI 10.1016/S0002-9378(98)70010-9 PN 1 PG 6 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 151CD UT WOS:000077702500023 PM 9855581 ER PT J AU Convertino, VA AF Convertino, VA TI Gender differences in autonomic functions associated with blood pressure regulation SO AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY LA English DT Article DE barorelfex; orthostasis; orthostatic hypotension; vasoconstriction ID BODY NEGATIVE-PRESSURE; DOWN BED REST; ORTHOSTATIC INTOLERANCE; BAROREFLEX RESPONSES; VAGAL BAROREFLEX; TOLERANCE; WOMEN; VOLUME; FITNESS; HUMANS AB Functions of carotid and aortic baroreflex control of heart rate (HR), cardiopulmonary baroreflex control of vascular resistance, adrenoreceptor responsiveness, indexes of baseline vagal and sympathetic tone, circulating blood volume, and venous compliance were compared in men and women to test the hypothesis that lower orthostatic tolerance in women would be associated with lower responsiveness of specific mechanisms of blood pressure regulation. HR, stroke volume (SV), cardiac output (Q), mean arterial blood pressure (MAP), central venous pressure, forearm (FVR) and leg (LVR) vascular resistance, catecholamines, and changes in leg volume (%Delta LV) were measured during various protocols of lower body negative pressure (LBNP), carotid stimulation, and infusions of adrenoreceptor agonists in 7 females and 10 males matched for age and fitness. LBNP tolerance for the women (797 +/- 63 mmHg/min) was 35% lower (P = 0.002) than 1,235 +/- 101 mmHg/min for the men. At presyacope, SV, Q, MAP, and %Delta LV were lower (P < 0.05) in females compared with males, whereas HR, FVR, and total peripheral resistance were similar in both groups. Lower LBNP tolerance in females was associated with reduced HR response to carotid baroreceptor stimulation, lower baseline cardiac vagal activity, greater decline in Q induced by LBNP, increased beta(1)-adrenoreceptor responsiveness, greater vasoconstriction under equal LBNP, lower levels of circulating NE at presyncope, and lower relative blood volume. The results of this investigation support the hypothesis that women have less responsiveness in mechanisms that underlie blood pressure regulation under orthostatic challenge. C1 USAF, Res Lab, Physiol Res Sect, Brooks AFB, TX 78235 USA. RP Convertino, VA (reprint author), USA, Inst Surg Res, 3400 Rawley E Chambers Ave,Bldg 3611, Ft Sam Houston, TX 78234 USA. NR 38 TC 145 Z9 145 U1 1 U2 10 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0363-6119 J9 AM J PHYSIOL-REG I JI Am. J. Physiol.-Regul. Integr. Comp. Physiol. PD DEC PY 1998 VL 275 IS 6 BP R1909 EP R1920 PG 12 WC Physiology SC Physiology GA 155YA UT WOS:000077973200020 PM 9843880 ER PT J AU Fisher, AR Mason, PH Wagenhals, KS AF Fisher, AR Mason, PH Wagenhals, KS TI Ruptured plantar epidermal inclusion cyst SO AMERICAN JOURNAL OF ROENTGENOLOGY LA English DT Article C1 Scott AFB Med Ctr, Scott AFB, IL 62225 USA. Med Diagnost Lab, Swansea, IL 62226 USA. RP Fisher, AR (reprint author), Scott AFB Med Ctr, Scott AFB, IL 62225 USA. NR 4 TC 14 Z9 14 U1 0 U2 0 PU AMER ROENTGEN RAY SOC PI RESTON PA 1891 PRESTON WHITE DR, SUBSCRIPTION FULFILLMENT, RESTON, VA 22091 USA SN 0361-803X J9 AM J ROENTGENOL JI Am. J. Roentgenol. PD DEC PY 1998 VL 171 IS 6 BP 1709 EP 1710 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 140XB UT WOS:000077114000059 PM 9843324 ER PT J AU Donahue, PE Smith, DL Yellin, AE Mintz, SJ Bur, F Luke, DR AF Donahue, PE Smith, DL Yellin, AE Mintz, SJ Bur, F Luke, DR CA Trovafloxacin Surg Grp TI Trovafloxacin in the treatment of intra-abdominal infections: Results of a double blind, multicenter comparison with imipenem/cilastatin SO AMERICAN JOURNAL OF SURGERY LA English DT Article ID IN-VITRO ACTIVITIES; INTRAABDOMINAL INFECTIONS; IMIPENEM-CILASTATIN; PIPERACILLIN-TAZOBACTAM; BACTERIAL-INFECTIONS; METRONIDAZOLE; CIPROFLOXACIN; CP-99,219; FLUOROQUINOLONE; TRIAL AB BACKGROUND: Trovafloxacin, a new broad-spectrum fourth-generation quinolone, has in vitro activity against most gram-negative and grampositive anaerobes and aerobes. Trovafloxiacin is available as both an intravenous formulation, alatrofloxacin, and a single daily oral tablet. Excellent tissue pharmacokinetics and oral bioavailability suggest usefulness in the treatment of complicated intra-abdominal infections. Thus, the efficacy of alatrofloxacin followed by oral trovafloxacin was compared with the standard regimen of intravenous imipenem/cilastatin followed by oral amoxicillin/clavulanic acid in this prospective, multicenter, double-blind trial. METHODS: Patients were randomized to receive either 300 mg alatrofloxacin daily followed by 200 mg oral trovafloxacin daily or 1 g imipenem/cilastatin intravenously thrice daily followed by 500 mg oral amoxicillin/clavulanic acid thrice daily for up to 14 days following surgical intervention of a documented intra-abdominal infection. Efficacy was assessed at the end of therapy and at follow-up (day 30). RESULTS: At the end of the study, cure or improvement occurred in 83% (129/156) and 84% (127/152) of clinically evaluable patients in the trovafloxacin and comparative groups, respectively. Pathogen eradication rates, adverse-event profiles, and significant laboratory abnormalities were comparable between groups. CONCLUSION: Intravenous alatrofloxacin with or without oral trovafloxacin was as effective as intravenous imipenem/cilastatin followed by oral amoxicillin/clavulanic acid in complicated intraabdominal infections. (C) 1998 by Excerpta Medica, Inc. C1 Cook Cty Hosp, Chicago, IL 60612 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Los Angeles Cty & Univ So Calif, Med Ctr, Los Angeles, CA USA. Salt Lake Reg Med Ctr, Salt Lake City, UT USA. Hop Notre Dame de Bon Secours, Metz, France. Pfizer Inc, Dept Clin Res, Groton, CT 06340 USA. RP Donahue, PE (reprint author), Cook Cty Hosp, 1835 W Harrison St,Room 6428 Main Bldg, Chicago, IL 60612 USA. NR 39 TC 23 Z9 24 U1 0 U2 1 PU CAHNERS PUBL CO PI NEW YORK PA 249 WEST 17 STREET, NEW YORK, NY 10011 USA SN 0002-9610 J9 AM J SURG JI Am. J. Surg. PD DEC PY 1998 VL 176 IS 6 SU S BP 53S EP 61S DI 10.1016/S0002-9610(98)00221-9 PG 9 WC Surgery SC Surgery GA 163TZ UT WOS:000078423100011 PM 9935258 ER PT J AU Nadeau, LJ Sayler, GS Spain, JC AF Nadeau, LJ Sayler, GS Spain, JC TI Oxidation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) by Alcaligenes eutrophus A5 SO ARCHIVES OF MICROBIOLOGY LA English DT Article DE DDT dioxygenation; Alcaligenes eutrophus A5; dioxygenase; DDT-2,3-dihydrodiol; polychlorinated aromatic compound ID CHROMATOGRAPHY MASS-SPECTROMETRY; SP STRAIN LB400; POLYCHLORINATED-BIPHENYLS; PSEUDOMONAS SP; CHLORINE SUBSTITUTION; ESCHERICHIA-COLI; SUBSTRATE RANGE; DEGRADATION; NAPHTHALENE; EXPRESSION AB Previous studies demonstrated that Alcaligenes eutrophus A5 transforms 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) to 4-chlorobenzoate via a meta-ring fission product. The initial reactions could be catalyzed by either monooxygenase or dioxygenase enzymes. In the present study, a transient intermediate that accumulated during the transformation of DDT by the biphenyl-grown cells was identified as 1,1,1-trichloro-2-(4-chlorophenyl-2,3-dihydro-4,6-cyclohexadiene)-2-(4'-chlorophenyl)ethane (DDT-2,3-dihydrodiol) on the basis of mass spectral analysis after n-butylboronic acid derivatization. The dihydrodiol undergoes a characteristic acid-catalyzed dehydration to produce phenols. H-1-NMR indicated a cis-relative stereochemistry. The results indicate that the biphenyl dioxygenase from A. eutrophus A5 catalyzes the dihydroxylation of DDT at the unsubstituted carbons on the aromatic ring to produce DDT-2,3-dihydrodiol. C1 USAF, Armstrong Lab, AFRL, MLQR, Tyndall AFB, FL 32403 USA. Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37996 USA. RP Spain, JC (reprint author), USAF, Armstrong Lab, AFRL, MLQR, 139 Barnes Dr,Suite 2, Tyndall AFB, FL 32403 USA. EM jspain@ccmail.alcq.tyndall.af.mil NR 35 TC 18 Z9 18 U1 3 U2 14 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0302-8933 J9 ARCH MICROBIOL JI Arch. Microbiol. PD DEC PY 1998 VL 171 IS 1 BP 44 EP 49 DI 10.1007/s002030050676 PG 6 WC Microbiology SC Microbiology GA 150FC UT WOS:000077652200007 PM 9871018 ER PT J AU Carey, SJ Clark, FO Egan, MP Price, SD Shipman, RF Kuchar, TA AF Carey, SJ Clark, FO Egan, MP Price, SD Shipman, RF Kuchar, TA TI The physical properties of the Midcourse Space Experiment galactic infrared-dark clouds SO ASTROPHYSICAL JOURNAL LA English DT Article DE dust, extinction; infrared : ISM : continuum; ISM : clouds; ISM : molecules ID CENTER MOLECULAR CLOUDS; FORMALDEHYDE; GRAINS; TEMPERATURE; EXCITATION; DEPLETION; NGC-2024; REGIONS; MODELS; CORES AB The SPIRIT III infrared telescope on the Midcourse Space Experiment (MSX) satellite has provided an unprecedented view of the mid-infrared emission (8-25 mu m) of the Galactic plane. An initial analysis of images from MSX Galactic plane survey data reveals dark clouds seen in silhouette against the bright emission from the Galactic plane (Egan et al.). These clouds have mid-infrared extinctions in excess of 2 mag at 8 mu m. We probed the physical properties of 10 of these MSX dark clouds using millimeter-wave molecular rotational lines as an indicator of dense molecular gas. All 10 clouds were detected in millimeter spectral lines of H(2)CO, which confirms the presence of dense gas. The distances to these clouds range from 1 to 8 kiloparsecs and their diameters from 0.4 to 15.0 pc. Excitation analysis of the observed lines indicates that the clouds are cold (T < 20 K) and dense [n(H(2)) > 10(5) cm(-3)]. Some of the clouds have nearby H II regions, H(2)O masers, and other tracers of star formation at comparable spectral line velocities; however, only one cloud contains embedded centimeter or infrared sources. The lack of mid- to far-infrared emission associated with these clouds suggests that they are not currently forming high-mass stars. If star formation is present in these clouds, it is clearly protostellar class 0 or earlier. C1 Boston Coll, Inst Sci Res, Chestnut Hill, MA 02167 USA. USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. RP Carey, SJ (reprint author), Boston Coll, Inst Sci Res, Chestnut Hill, MA 02167 USA. EM carey@pldac.plh.af.mil; fclark@plh.af.mil; egan@plh.af.mil; price@plh.af.mil; shipman@plh.af.mil; kuchar@pldac.plh.af.mil NR 42 TC 176 Z9 177 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 721 EP 728 DI 10.1086/306438 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500028 ER PT J AU Hearon, CM Fischer, MD Dooley, JW AF Hearon, CM Fischer, MD Dooley, JW TI Male/Female SACM endurance comparison: Support for the armstrong laboratory modifications to the CSU-13B/P anti-G suit SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID PREDICTING BODY DENSITY; GENERALIZED EQUATIONS AB Background: The standard anti-G suit (CSU-13B/P) was designed based on male body structure. Females differ from males with respect to body proportionality. In Armstrong Laboratory (AL) studies, females have terminated centrifuge simulated air combat maneuvers (SACM) because of anti-G suit (CSU-13B/P modified according to original T.O. 14P3-6-121)(OTO) discomfort. AL modifications to the suit have since been adopted in the OTO in an attempt to provide females a best-fit suit (AL Mod). The study examined male/female SACM endurance with females wearing both the OTO and the AL Mod suits. Methods: There were 6 females and 8 males who performed a +5.0 to +9.0 Gz SACM to fatigue using the anti-G straining maneuver with anti-G suit inflation. The females performed in both the OTO and AL Mod suits while the males performed in the OTO suit only (OTO was their best-fit suit). Results: Wearing the OTO, males performed the SACM significantly longer than the females, three of whom reported severe suit discomfort. However, when the females wore the AL Mod suit, their SACM endurance almost doubled over their OTO performance and none reported suit discomfort. When wearing their best-fit suits, there was no significant gender difference in SACM endurance. Conclusions: These data support the efficacy of the AL modifications to the CSU-13B/P anti-G suit through greatly improved performance during the +5.0 to +9.0 SACM in females. These data also suggest that, in the small sample examined, when fitted with a best-fit anti-G suit, females can endure the +5.0 to +9.0 SACM to the same degree as males. C1 USAF, Res Lab, Crew Technol Div, Flight Mot Effects Branch, Brooks AFB, TX USA. Wyle Life Sci, Brooks AFB, TX USA. RP Hearon, CM (reprint author), NE Illinois Univ, Dept Biol & Exercise Sci, 5500 N St Louis Ave, Chicago, IL 60625 USA. NR 15 TC 1 Z9 2 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD DEC PY 1998 VL 69 IS 12 BP 1141 EP 1145 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 142DF UT WOS:000077184100003 PM 9856537 ER PT J AU Peterson, AL Halstead, TS AF Peterson, AL Halstead, TS TI Group cognitive behavior therapy for depression in a community setting: A clinical replication series SO BEHAVIOR THERAPY LA English DT Article ID PSYCHODYNAMIC-INTERPERSONAL PSYCHOTHERAPY; PROBLEM-SOLVING THERAPY; UNIPOLAR DEPRESSION; TREATMENT DURATION; MAJOR DEPRESSION; PROGRAM; PHARMACOTHERAPY; SEVERITY; WOMEN AB Several controlled treatment-outcome studies have demonstrated the clinical efficacy of group behavioral and cognitive behavioral treatments for depression. However, there is a significant lack of evidence on mental health outcome evaluation studies for depression conducted in nonresearch clinical settings. Subjects in research settings may represent only about 20% of the clinical population because of stringent inclusion criteria, requirements to accept random assignment to conditions, etc. The present study is a clinical replication series of the effectiveness of group cognitive behavior therapy for depression administered in a nonresearch community setting. The subjects included 138 adult patients referred by mental health clinic providers for participation in a six-session (12-hour) depression management group. Outcome measures using the Beck Depression Inventory indicated that the level of depression was decreased for 84% of the participants, the average reduction in depression as measured by the BDI was 38%, and 43% of the patients had a greater than 50% reduction in their BDI score. The results indicated that group cognitive behavior therapy can be effectively applied in a clinical setting with a heterogeneous patient population, although the magnitude of the treatment effect was somewhat less than found in research settings (38% reduction on the BDI as compared to 57%). Group cognitive behavior therapy is a cost-effective treatment approach and the potential for benefits significantly outweighs the cost. In this era of managed care initiatives, group cognitive behavior therapy for depression should be considered as a first-line treatment intervention for many patients with depression as part of a stepped-care treatment approach to provide "the best treatment at the best value.". RP Peterson, AL (reprint author), Wilford Hall USAF Med Ctr, MMPBB, Behav Hlth Psychol Serv, 2200 Bergquist Dr,Suite 1, San Antonio, TX 78236 USA. NR 52 TC 35 Z9 35 U1 1 U2 6 PU ASSOC ADV BEHAVIOR THERAPY PI NEW YORK PA 305 7TH AVE #16A, NEW YORK, NY 10001-6008 USA SN 0005-7894 J9 BEHAV THER JI Behav. Therapy PD WIN PY 1998 VL 29 IS 1 BP 3 EP 18 DI 10.1016/S0005-7894(98)80015-4 PG 16 WC Psychology, Clinical SC Psychology GA ZX789 UT WOS:000074555600002 ER PT J AU Kiel, JL Alls, JL Holwitt, EA Stribling, LJV Parker, JE AF Kiel, JL Alls, JL Holwitt, EA Stribling, LJV Parker, JE TI Thermochemiluminescence as a technique for radio frequency radiation dosimetry SO BIOELECTROCHEMISTRY AND BIOENERGETICS LA English DT Article; Proceedings Paper CT International Scientific Meeting on Electromagnetics in Medicine and Biology CY NOV 03-05, 1997 CL CHICAGO, ILLINOIS DE radio frequency radiation; specific absorption rate; diazoluminomelanin; thermochemiluminescence; delayed fluorescence; computational chemistry AB Radio frequency radiation (RFR) dosimetry is based on the rate of absorbed energy (specific absorption rate: SAR) per unit mass. It is most conveniently measured by acquiring changes in temperature per unit time and converting the results to joules per second (watts) per kilogram, based on the specific heat of the biological material interacting with the RFR. To date, SAR has been predicted by modeling based on the dielectric properties of tissues, or measured by infrared (IR) thermography or with macroscopic high-resistance thermistors or thermofluorescent macroscopic point probes. Thermochemiluminescence (TCL) was invented to provide a high degree of continuous spatial and temporal thermal resolution in phantoms. It is defined as the steady-state emission of visible light from a peroxidizing mixture based on the temperature of the mixture. The best material for this purpose, to date, is diazoluminomelanin (DALM). Unfortunately, standardization of the synthesis (chemical composition) of this polymer and its thermal response constant (thermal quantum efficiency) has been difficult. This paper presents a biosynthetic method for the large-scale production of the polymer and a computational method far directly determining the SAR from the luminescence. Published by Elsevier Science S.A. C1 USAF, Res Lab, Directed Energy Bioeffects Div, HEDB, Brooks AFB, TX 78235 USA. RP Kiel, JL (reprint author), USAF, Res Lab, Directed Energy Bioeffects Div, HEDB, 2503 Gillingham Dr,Bldg 175E, Brooks AFB, TX 78235 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0302-4598 J9 BIOELECTROCH BIOENER JI Bioelectrochem. Bioenerg. PD DEC PY 1998 VL 47 IS 2 BP 253 EP 257 DI 10.1016/S0302-4598(98)00196-2 PG 5 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 158JV UT WOS:000078113000010 ER PT J AU Lincks, J Boyan, BD Blanchard, CR Lohmann, CH Liu, Y Cochran, DL Dean, DD Schwartz, Z AF Lincks, J Boyan, BD Blanchard, CR Lohmann, CH Liu, Y Cochran, DL Dean, DD Schwartz, Z TI Response of MG63 osteoblast-like cells to titanium and titanium alloy is dependent on surface roughness and composition SO BIOMATERIALS LA English DT Article DE osteoblasts; titanium; titanium alloy; surface roughness; PGE(2); TGF-beta; in vitro ID GROWTH-FACTOR-BETA; EXTRACELLULAR-MATRIX; ALKALINE-PHOSPHATASE; CARTILAGE CELLS; TGF-BETA; BONE; DIFFERENTIATION; INVITRO; PROLIFERATION; IMPLANTS AB The success of an implant is determined by its integration into the tissue surrounding the biomaterial. Surface roughness and composition are considered to influence the properties of adherent cells. The aim of this study was to determine the effect of chemical composition and surface roughness of commercially pure titanium (Ti) and Ti-6Al-4V alloy (Ti-A) on MG63 osteoblast-like cells. Unalloyed and alloyed Ti disks were machined and either fine-polished or wet-ground, resulting in smooth (S) and rough (R) finishes, respectively. Standard tissue culture plastic was used as a control. Surface topography and profile were evaluated by cold field emission scanning electron microscopy and profilometry, while chemical composition was determined using Auger electron spectroscopy and Fourier transform infrared spectroscopy. The effect on the cells was evaluated 24 h postconfluence by measuring cell number, [H-3]-thymidine incorporation into DNA, cell and cell layer alkaline phosphatase specific activity (ALPase), osteocalcin and collagen production, [S-35]-sulfate incorporation into proteoglycan, and prostaglandin E-2 (PGE(2)) and transforming growth factor-beta (TGF-beta) production. When compared to plastic, the number of cells was reduced on the pure Ti surfaces, while it was equivalent on the Ti-A surfaces; [H-3]-thymidine incorporation was reduced on all surfaces. The stimulatory effect of surface roughness on ALPase in isolated cells and the cell layer was more pronounced on the rougher surfaces, with enzyme activity on TI-R being greater than on TfA-R. Osteocalcin production was increased only on the TI-R surface. Collagen production was decreased on Ti surfaces except Ti-R; [S-35]-sulfate incorporation was reduced on all surfaces. Surface roughness affected local factor production (TGF-beta, PGE(2)). The stimulatory effect of the rougher surfaces on PGE(2) and TGF-beta was greater on Ti than Ti-A. In summary, cell proliferation, differentiation, protein synthesis and local factor production were affected by surface roughness and composition. Enhanced differentiation of cells grown on rough vs. smooth surfaces for both Ti and Ti-A surfaces was indicated by decreased proliferation and increased ALPase and osteocalcin production. Local factor production was also enhanced on rough surfaces, supporting the contention that these cells are more differentiated. Surface composition also played a role in cell differentiation, since cells cultured on Ti-R surfaces produced more ALPase than those cultured on Ti-A-R. While it is still unknown which material properties induce which cellular responses, this study suggests that surface roughness and composition may play a major role and that the best design for an orthopaedic implant is a pure titanium surface with a rough microtopography. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Texas, Hlth Sci Ctr, Dept Periodont, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Univ Texas, Hlth Sci Ctr, Dept Orthopaed, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Biochem, San Antonio, TX 78284 USA. SW Res Inst, San Antonio, TX USA. Hebrew Univ Jerusalem, Hadassah Fac Dent Med, Dept Periodont, Jerusalem, Israel. RP Boyan, BD (reprint author), Univ Texas, Hlth Sci Ctr, Dept Periodont, San Antonio, TX 78284 USA. EM BoyanB@uthscsa.edu OI Dean, David/0000-0002-4512-9065 NR 57 TC 454 Z9 459 U1 8 U2 84 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-9612 J9 BIOMATERIALS JI Biomaterials PD DEC PY 1998 VL 19 IS 23 BP 2219 EP 2232 DI 10.1016/S0142-9612(98)00144-6 PG 14 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA 146QE UT WOS:000077441200012 PM 9884063 ER PT J AU Palazotto, AN Gummadi, LNB Vaidya, UK Herup, EJ AF Palazotto, AN Gummadi, LNB Vaidya, UK Herup, EJ TI Low velocity impact damage characteristics of Z-fiber reinforced sandwich panels - an experimental study SO COMPOSITE STRUCTURES LA English DT Article DE Z-fiber reinforced sandwich panels; low velocity impact testing; nondestructive evaluation AB Experimental results related to the initiation of damage in Z-fiber truss-reinforced sandwich panels are presented. Two different orientations of Fin angles are considered. A pendulum-type impactor is used to impart very low levels of impact energy. Threshold energy levels at which the observable damage initiation occurs are determined. Nondestructive evaluation studies conducted prior to the impact are compared with the post-impact status of the panels for assessing the type and magnitude of the damage. These studies include ultrasonic inspection, microscopic inspection and acoustic emission tests. Damage is also evaluated by carrying out vibration tests before and after impact. Static indentation tests are carried out to compare with low velocity impact tests. Effects specific to the impact phenomena are studied by comparing the load displacement characteristics. Compression after impact characteristics are also evaluated. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Palazotto, AN (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 8 TC 8 Z9 12 U1 0 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0263-8223 J9 COMPOS STRUCT JI Compos. Struct. PD DEC PY 1998 VL 43 IS 4 BP 275 EP 288 DI 10.1016/S0263-8223(98)00110-X PG 14 WC Materials Science, Composites SC Materials Science GA 175DP UT WOS:000079077800002 ER PT J AU Jones, SE Rule, WK Jerome, DM Klug, RT AF Jones, SE Rule, WK Jerome, DM Klug, RT TI On the optimal nose geometry for a rigid penetrator SO COMPUTATIONAL MECHANICS LA English DT Article ID TARGETS; RODS AB A variational formulation for the net force on the nose of a rigid projectile normally penetrating a compliant target is given. Frictional effects are negligible in this formulation. The variational problem is solved and the result compared to several popular nose geometries. For blunt tipped projectiles, the optimal geometry can significantly enhance penetration by reducing the net force of resistance. For long penetrator noses, the effect has much less value. The most interesting conclusion is that all the optimal geometries have blunt tips. C1 USAF, Eglin AFB, FL 32542 USA. Univ Alabama, Dept Aerosp Engn & Mech, Tuscaloosa, AL 35487 USA. RP Jones, SE (reprint author), USAF, Eglin AFB, FL 32542 USA. NR 16 TC 19 Z9 23 U1 2 U2 5 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0178-7675 J9 COMPUT MECH JI Comput. Mech. PD DEC PY 1998 VL 22 IS 5 BP 413 EP 417 DI 10.1007/s004660050373 PG 5 WC Mathematics, Interdisciplinary Applications; Mechanics SC Mathematics; Mechanics GA 154TA UT WOS:000077903800006 ER PT J AU Josephs, JD Farmer, JC AF Josephs, JD Farmer, JC TI Hypothermia and extracorporeal rewarming: The journey toward a less invasive, more accessible methodology SO CRITICAL CARE MEDICINE LA English DT Editorial Material DE hypothermia; extracorporeal rewarming; venovenous rewarming circuit; cardiopulmonary bypass ID ACCIDENTAL HYPOTHERMIA C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA. RP Josephs, JD (reprint author), Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0090-3493 J9 CRIT CARE MED JI Crit. Care Med. PD DEC PY 1998 VL 26 IS 12 BP 1944 EP 1945 DI 10.1097/00003246-199812000-00009 PG 2 WC Critical Care Medicine SC General & Internal Medicine GA 151RA UT WOS:000077733400008 PM 9875894 ER PT J AU Fiser, RT Torres, A Butch, AW Valentine, JL AF Fiser, RT Torres, A Butch, AW Valentine, JL TI Ionized magnesium concentrations in critically ill children SO CRITICAL CARE MEDICINE LA English DT Article DE ionized magnesium; critical care; pediatrics; ion selective electrodes; ionized calcium; intensive care unit; magnesium deficiency; sepsis; cardiac surgery; head injury ID DEPENDENT DIABETES-MELLITUS; WHOLE-BLOOD; CARDIOPULMONARY BYPASS; PEDIATRIC-PATIENTS; INTENSIVE-CARE; HEAD TRAUMA; SERUM; HYPOMAGNESEMIA; DEFICIENCY; MORTALITY AB Objective: To test the hypothesis that many critically ill children exhibit ionized hypomagnesemia despite having normal total magnesium (TMg) concentrations. Design: A prospective, observational study with convenience sampling. Setting: Pediatric and cardiovascular intensive care units of a large children's hospital. Patients: Patients aged 1 day to 21 yrs admitted from January 1 to October 31, 1996, Patients with chronic renal failure or weight <3 kg were excluded. A group of healthy children involved in a school-based nutritional assessment study were also studied. Interventions: None. Measurements and Main Results: Sixty seven patients (5.4 +/- 5.7 [SD] yrs) and 24 healthy children (10.84 +/- 0.93 yrs, p < .001) were studied. Plasma was assayed for ionized magnesium (IMg) using a blood analyzer. Forty (59%)/67 critically ill subjects had IMg concentrations <0.40 mmol/L, the lowest published normal value and the lowest value observed in our group of healthy children. Of these, 24 (60%)/40 had normal TMg concentrations, IMg was significantly (p = .00) lower in critically ill subjects than in the group of healthy children (0.37 +/- 0.10 mmol/L vs, 0.46 +/- 0.03 mmol/L), IMg did not correlate strongly with ionized calcium (r(2) = 0.49), albumin (r(2) = 0.09), or pH (r(2) = 0.18). Conclusion: Many critically ill children exhibit ionized hypomagnesemia with normal TMg concentrations, These children would not be recognized as magnesium deficient based on routine TMg testing. Critically ill children exhibited significantly lower concentrations of IMg than a group of healthy children. C1 USAF, Med Ctr, WHMC, MNP, Lackland AFB, TX 78236 USA. Univ Illinois, Coll Med, Peoria, IL 61656 USA. Univ Arkansas Med Sci, Dept Pediat, Little Rock, AR 72205 USA. Univ Arkansas Med Sci, Dept Pathol, Little Rock, AR 72205 USA. RP Fiser, RT (reprint author), USAF, Med Ctr, WHMC, MNP, 2200 Bergquist Suite 1, Lackland AFB, TX 78236 USA. NR 39 TC 21 Z9 23 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0090-3493 J9 CRIT CARE MED JI Crit. Care Med. PD DEC PY 1998 VL 26 IS 12 BP 2048 EP 2052 DI 10.1097/00003246-199812000-00039 PG 5 WC Critical Care Medicine SC General & Internal Medicine GA 151RA UT WOS:000077733400033 PM 9875919 ER PT J AU McCarthy, DM AF McCarthy, DM TI H-pylori infection in non-ulcer patients - To treat or not to treat. The case against treatment SO EUROPEAN JOURNAL OF SURGERY LA English DT Article DE H-pylori; pathogen; amphibiote; eradication; esophagus; adenocarcinoma; reflux; antibiotic resistance ID GASTROESOPHAGEAL REFLUX DISEASE; HELICOBACTER-PYLORI; PEPTIC-ULCER; HOSPITAL ADMISSIONS; GASTRIC CARDIA; UNITED-STATES; ADENOCARCINOMA; ERADICATION; THERAPY; RESISTANCE AB Heretofore regarded as a strict pathogen, recent identification of multiple mutants of H. pylori, varying in pathogenicity, genomic composition, antigenic structure and other characteristics, has led to speculation that not all strains of the organism merit elimination. Affecting half the world's population, H. pylori appears to cause clinically significant disease in <20% of cases. The costs of eradicating harmless infection in over 2 billion people are prohibitive, particularly in countries lacking resources, and are questionable even in advanced countries where infection, gastritis and related diseases are declining as social conditions improve. Major controversies surround empiric eradication of helicobacter infection in patients with asymptomatic gastritis or non-specific dyspepsia. Apart from cost, and feasibility, there are concerns that widespread campaigns to eradicate H. pylori might cause major increases in esophageal reflux disease and esophageal adenocarcinoma, while causing some serious iatrogenic illness and increasing antibiotic resistance, with uncertain consequences to affected populations. C1 USAF, VA, Med Ctr, Gastroenterol Sect, Albuquerque, NM 87108 USA. Univ New Mexico, Div Gastroenterol & Hepatol, Albuquerque, NM 87131 USA. RP McCarthy, DM (reprint author), USAF, VA, Med Ctr, Gastroenterol Sect, 111F,2100 Ridgecrest Dr SE, Albuquerque, NM 87108 USA. EM mccarthy.denis@albuquerque.va.gov NR 47 TC 4 Z9 4 U1 0 U2 0 PU SCANDINAVIAN UNIVERSITY PRESS PI OSLO PA PO BOX 2959 TOYEN, JOURNAL DIVISION CUSTOMER SERVICE, N-0608 OSLO, NORWAY SN 1102-4151 J9 EUR J SURG JI Eur. J. Surg. PD DEC PY 1998 VL 164 SU 582 BP 11 EP 15 DI 10.1080/11024159850191382 PG 5 WC Surgery SC Surgery GA 162HN UT WOS:000078340200003 ER PT J AU McCarthy, DM AF McCarthy, DM TI Future aspects of functional gastrointestinal disease: How should treatments be evaluated SO EUROPEAN JOURNAL OF SURGERY LA English DT Article DE strategy; clinical trials; symptom clusters; overlap syndromes; definitions; psychiatric diagnoses; study design; patient selection ID IRRITABLE-BOWEL-SYNDROME; DYSPEPSIA SUBGROUPS; NONULCER DYSPEPSIA AB Evaluation can only be approached when groups to receive any form of therapy are well defined. To make progress in an area now confused, the best strategy would seem to involve separating from the mass of FGD patients, sub-groups which are well defined by tight diagnostic criteria, and initially Limiting all research, including clinical trials, to such groups. Overlapping syndromes can be studied later. Clearly defined psychiatric illnesses should be diagnosed by DSM criteria and excluded from study. While research and long-term clinical trials should be limited to tightly defined groups, short-term responses to specific therapies could be used to define the groups, following which clinical clusters for that group could be re-evaluated. In broad terms, across-the-board attention to visceral sensitivity, nervous function and psychosocial factors seem more likely to yield insights in IBS than in NUD, but at present no confident statements can be made about pathogenesis in either group. Further clinical trials performed as in the past, are largely inappropriate at this time. C1 Univ New Mexico, Div Gastroenterol & Hepatol, Albuquerque, NM 87131 USA. USAF, VA New Mexico Reg Fed Med Ctr, Gastroenterol Sect, Albuquerque, NM USA. RP McCarthy, DM (reprint author), VA Med Ctr, 111F,1501 San Pedro SE, Albuquerque, NM 87108 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU SCANDINAVIAN UNIVERSITY PRESS PI OSLO PA PO BOX 2959 TOYEN, JOURNAL DIVISION CUSTOMER SERVICE, N-0608 OSLO, NORWAY SN 1102-4151 J9 EUR J SURG JI Eur. J. Surg. PD DEC PY 1998 VL 164 SU 583 BP 98 EP 103 DI 10.1080/11024159850191337 PG 6 WC Surgery SC Surgery GA 162HQ UT WOS:000078340400018 ER PT J AU Gavrielides, A Kottos, T Kovanis, V Tsironis, GP AF Gavrielides, A Kottos, T Kovanis, V Tsironis, GP TI Self-organisation of coupled nonlinear oscillators through impurities SO EUROPHYSICS LETTERS LA English DT Article ID DISORDER AB The effects of impurities introduced into a lattice of strongly coupled oscillators are studied. Contrary to our expectations, a single impurity can control the chaotic behavior of a long array of chaotic oscillators and bring about complete synchronization. This effect appears to be independent of the length of the chain, obtaining self-organization for chains as long as 512 lattice sites. By appropriately introducing more that one impurity, if needed, longer chains of oscillators can be tamed. C1 USAF, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. Weizmann Inst Sci, Dept Phys Complex Syst, IL-76100 Rehovot, Israel. Univ Crete, Dept Phys, GR-71003 Heraklion, Crete, Greece. Fdn Res & Technol Hellas, GR-71003 Heraklion, Crete, Greece. RP Gavrielides, A (reprint author), USAF, Nonlinear Opt Grp, 3550 Aberdeen Ave, Kirtland AFB, NM 87117 USA. RI Tsironis, George/C-2683-2011 NR 5 TC 8 Z9 8 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD DEC 1 PY 1998 VL 44 IS 5 BP 559 EP 564 DI 10.1209/epl/i1998-00509-0 PG 6 WC Physics, Multidisciplinary SC Physics GA 145CK UT WOS:000077353300004 ER PT J AU Wood, EF Lettenmaier, DP Liang, X Lohmann, D Boone, A Chang, S Chen, F Dai, YJ Dickinson, RE Duan, QY Ek, M Gusev, YM Habets, F Irannejad, P Koster, R Mitchel, KE Nasonova, ON Noilhan, J Schaake, J Schlosser, A Shao, YP Shmakin, AB Verseghy, D Warrach, K Wetzel, P Xue, YK Yang, ZL Zeng, QC AF Wood, EF Lettenmaier, DP Liang, X Lohmann, D Boone, A Chang, S Chen, F Dai, YJ Dickinson, RE Duan, QY Ek, M Gusev, YM Habets, F Irannejad, P Koster, R Mitchel, KE Nasonova, ON Noilhan, J Schaake, J Schlosser, A Shao, YP Shmakin, AB Verseghy, D Warrach, K Wetzel, P Xue, YK Yang, ZL Zeng, QC TI The Project for Intercomparison of Land-surface Parameterization Schemes (PILPS) phase 2(c) Red-Arkansas River basin experiment: 1. Experiment description and summary intercomparisons SO GLOBAL AND PLANETARY CHANGE LA English DT Article; Proceedings Paper CT Project for Intercomparison of Landsurface Parameterization Schemes Workshop (PILPS) CY JUN, 1997 CL MELBOURNE, AUSTRALIA DE PILPS; land-surface parameterization; continental river basin modeling; energy/water balance; calibration of land-surface schemes; Red-Arkansas River basin AB 0Sixteen land-surface schemes participating in the Project for the Intercomparison of Land-surface Schemes (PILPS) Phase 2(c) were run using 10 years (1979-1988) of forcing data for the Red-Arkansas River basins in the Southern Great Plains region of the United States. Forcing data (precipitation, incoming radiation and surface meteorology) and land-surface characteristics (soil and vegetation parameters) were provided to each of the participating schemes. Two groups of runs are presented. (1) Calibration-validation runs, using data from six small catchments distributed across the modeling domain. These runs were designed to test the ability of the schemes to transfer information about model parameters to other catchments and to the computational grid boxes. (2) Base-runs, using data for 1979-1988, designed to evaluate the ability of the schemes to reproduce measured energy and water fluxes over multiple seasonal cycles across a climatically diverse, continental-scale basin. All schemes completed the base-runs but five schemes chose not to calibrate. Observational data (from 1980-1986) including daily river flows and monthly basin total evaporation estimated through an atmospheric budget analysis, were used to evaluate model performance. In general, the results are consistent with earlier PILPS experiments in terms of differences among models in predicted water and energy fluxes. The mean annual net radiation varied between 80 and 105 W m(-2) (excluding one model). The mean annual Bowen ratio varied from 0.52 to 1.73 (also excluding one model) as compared to the data-estimated value of 0.92. The run-off ratios varied from a low of 0.02 to a high of 0.41, as compared to an observed value of 0.15. In general, those schemes that did not calibrate performed worse, not only on the validation catchments, but also at the scale of the entire modeling domain. This suggests that further PILPS experiments on the value of calibration need to be carried out. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Dept Civil Engn & Operat Res, Princeton, NJ 08544 USA. Univ Washington, Dept Civil Engn, Seattle, WA 98195 USA. NASA, Goddard Space Flight Ctr, Mesoscale Dynam & Precipitat Branch, Greenbelt, MD 20771 USA. USAF, Res Lab, Hanscom AFB, MA USA. NOAA, NCEP, Environm Modeling Ctr, Camp Springs, MD USA. Chinese Acad Sci, Inst Atmospher Phys, Beijing, Peoples R China. Univ Arizona, Inst Atmospher Phys, Tucson, AZ USA. NOAA, Natl Weather Serv, Off Hydrol, Silver Spring, MD 20910 USA. Oregon State Univ, Corvallis, OR 97331 USA. Russian Acad Sci, Inst Water Problems, Moscow, Russia. Meteo France, CNRM, Toulouse, France. Univ New S Wales, Ctr Adv Numer Computat Engn & Sci, Sydney, NSW 2052, Australia. NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. NOAA, GFDL, Princeton, NJ USA. Russian Acad Sci, Inst Geog, Moscow, Russia. Climate Res Branch, Atmospher Environm Serv, Toronto, ON, Canada. GKSS Forschungszentrum Geesthacht GmbH, Res Ctr, D-2054 Geesthacht, Germany. Ctr Ocean Land Atmosphere Studies, Calverton, MD USA. RP Wood, EF (reprint author), Princeton Univ, Dept Civil Engn & Operat Res, Princeton, NJ 08544 USA. RI Dai, Yongjiu/D-1070-2010; Yang, Zong-Liang/B-4916-2011; Koster, Randal/F-5881-2012; Chen, Fei/B-1747-2009; lettenmaier, dennis/F-8780-2011; Nasonova, Olga/B-6093-2014; Duan, Qingyun/C-7652-2011; gusev, yugeniy/G-4711-2014; Shao, Yaping/G-3606-2013; Dai, Yongjiu/D-6261-2014; OI Habets, Florence/0000-0003-1950-0921; Koster, Randal/0000-0001-6418-6383; lettenmaier, dennis/0000-0003-3317-1327; Duan, Qingyun/0000-0001-9955-1512; gusev, yugeniy/0000-0003-3886-2143; Shao, Yaping/0000-0002-2041-5479; Dai, Yongjiu/0000-0002-3588-6644; Wood, Eric/0000-0001-7037-9675 NR 17 TC 208 Z9 228 U1 1 U2 25 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 EI 1872-6364 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD DEC PY 1998 VL 19 IS 1-4 BP 115 EP 135 DI 10.1016/S0921-8181(98)00044-7 PG 21 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 139GF UT WOS:000077019100008 ER PT J AU Liang, X Wood, EF Lettenmaier, DP Lohmann, D Boone, A Chang, S Chen, F Dai, YJ Desborough, C Dickinson, RE Duan, QY Ek, M Gusev, YM Habets, F Irannejad, P Koster, R Mitchell, KE Nasonova, ON Noilhan, J Schaake, J Schlosser, A Shao, YP Shmakin, AB Verseghy, D Warrach, K Wetzel, P Xue, YK Yang, ZL Zeng, QC AF Liang, X Wood, EF Lettenmaier, DP Lohmann, D Boone, A Chang, S Chen, F Dai, YJ Desborough, C Dickinson, RE Duan, QY Ek, M Gusev, YM Habets, F Irannejad, P Koster, R Mitchell, KE Nasonova, ON Noilhan, J Schaake, J Schlosser, A Shao, YP Shmakin, AB Verseghy, D Warrach, K Wetzel, P Xue, YK Yang, ZL Zeng, QC TI The Project for Intercomparison of Land-surface Parameterization Schemes (PILPS) phase 2(c) Red-Arkansas River basin experiment: 2. Spatial and temporal analysis of energy fluxes SO GLOBAL AND PLANETARY CHANGE LA English DT Article; Proceedings Paper CT Project for Intercomparison of Landsurface Parameterization Schemes Workshop (PILPS) CY JUN, 1997 CL MELBOURNE, AUSTRALIA DE PILPS; energy balance; land-surface models; Red-Arkansas River basin ID SOIL HEAT-FLUX; MODEL AB The energy components of sixteen Soil-Vegetation Atmospheric Transfer (SVAT) schemes were analyzed and intercompared using 10 years of surface meteorological and radiative forcing data from the Red-Arkansas River basin in the Southern Great Plains of the United States. Comparisons of simulated surface energy fluxes among models showed that the net radiation and surface temperature generally had the best agreement among the schemes. On an average (annual and monthly) basis, the estimated latent heat fluxes agreed (to within approximate estimation errors) with the latent heat fluxes derived from a radiosonde-based atmospheric budget method for slightly more than half of the schemes. The sensible heat fluxes had larger differences among the schemes than did the latent heat fluxes, and the model-simulated ground heat fluxes had large variations among the schemes. The spatial patterns of the model-computed net radiation and surface temperature were generally similar among the schemes, and appear reasonable and consistent with observations of related variables, such as surface air temperature. The spatial mean patterns of latent and sensible heat fluxes were less similar than for net radiation, and the spatial patterns of the ground heat flux vary greatly among the 16 schemes. Generally, there is less similarity among the models in the temporal (interannual) variability of surface fluxes and temperature than there is in the mean fields, even for schemes with similar mean fields. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Dept Civil Engn & Operat Res, Princeton, NJ 08544 USA. Univ Washington, Dept Civil Engn, Seattle, WA 98195 USA. NASA, Goddard Space Flight Ctr, Mesoscale Dynam & Precipitat Branch, Greenbelt, MD 20771 USA. USAF, Res Lab, Hanscom, MA USA. NOAA, NCEP, Environm Modeling Ctr, Camp Springs, MD USA. Chinese Acad Sci, Inst Atmospher Phys, Beijing, Peoples R China. Macquarie Univ, Climat Impacts Ctr, Sydney, NSW 2109, Australia. Univ Arizona, Inst Atmospher Phys, Tucson, AZ USA. NOAA, Natl Weather Serv, Off Hydrol, Silver Spring, MD 20910 USA. Oregon State Univ, Corvallis, OR 97331 USA. Russian Acad Sci, Inst Water Problems, Moscow, Russia. Meteo France, CNRM, Toulouse, France. Univ New S Wales, Ctr Adv Numer Computat Eng & Sci, Sydney, NSW 2052, Australia. NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. NOAA, GFDL, Princeton, NJ USA. Russian Acad Sci, Inst Geog, Moscow, Russia. Climate Res Branch, Atmospher Environm Serv, Toronto, ON, Canada. RP Liang, X (reprint author), Princeton Univ, Dept Civil Engn & Operat Res, Princeton, NJ 08544 USA. RI Dai, Yongjiu/D-1070-2010; Yang, Zong-Liang/B-4916-2011; Koster, Randal/F-5881-2012; Chen, Fei/B-1747-2009; lettenmaier, dennis/F-8780-2011; Nasonova, Olga/B-6093-2014; Duan, Qingyun/C-7652-2011; gusev, yugeniy/G-4711-2014; Shao, Yaping/G-3606-2013; Dai, Yongjiu/D-6261-2014 OI Wood, Eric/0000-0001-7037-9675; Habets, Florence/0000-0003-1950-0921; Koster, Randal/0000-0001-6418-6383; lettenmaier, dennis/0000-0003-3317-1327; Duan, Qingyun/0000-0001-9955-1512; gusev, yugeniy/0000-0003-3886-2143; Shao, Yaping/0000-0002-2041-5479; Dai, Yongjiu/0000-0002-3588-6644 NR 13 TC 73 Z9 82 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD DEC PY 1998 VL 19 IS 1-4 BP 137 EP 159 DI 10.1016/S0921-8181(98)00045-9 PG 23 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 139GF UT WOS:000077019100009 ER PT J AU Lohmann, D Lettenmaier, DP Liang, X Wood, EF Boone, A Chang, S Chen, F Dai, YJ Desborough, C Dickinson, RE Duan, QY Ek, M Gusev, YM Habets, F Irannejad, P Koster, R Mitchell, KE Nasonova, ON Noilhan, J Schaake, J Schlosser, A Shao, YP Shmakin, AB Verseghy, D Warrach, K Wetzel, P Xue, YK Yang, ZL Zeng, QC AF Lohmann, D Lettenmaier, DP Liang, X Wood, EF Boone, A Chang, S Chen, F Dai, YJ Desborough, C Dickinson, RE Duan, QY Ek, M Gusev, YM Habets, F Irannejad, P Koster, R Mitchell, KE Nasonova, ON Noilhan, J Schaake, J Schlosser, A Shao, YP Shmakin, AB Verseghy, D Warrach, K Wetzel, P Xue, YK Yang, ZL Zeng, QC TI The Project for Intercomparison of Land-surface Parameterization Schemes (PILPS) phase 2(c) Red-Arkansas River basin experiment: 3. Spatial and temporal analysis of water fluxes SO GLOBAL AND PLANETARY CHANGE LA English DT Article; Proceedings Paper CT Project for Intercomparison of Landsurface Parameterization Schemes Workshop (PILPS) CY JUN, 1997 CL MELBOURNE, AUSTRALIA DE PILPS; water balance; routing model; continental river basin modeling; Red-Arkansas River basin ID MODELS AB The water-balance components of 16 Soil-Vegetation Atmospheric Transfer (SVAT) schemes were evaluated by comparing predicted and observed streamflow, predicted evapotranspiration and evapotranspiration inferred from an atmospheric moisture budget analysis, and soil moisture storage changes for a seven-year period (1980-1986) using data from the Red-Arkansas River basins of the Southern Great Plains of the USA. The evaluations support the following suggestions: (a) The mean annual runoff of all models follows, at least generally, the strong climatic East-West gradient of precipitation, although most models predict too much runoff in the dry part of the basin. (b) The mean monthly storage change tends to be underestimated, even though all models capture reasonably well the seasonality of the evapotranspiration. (c) The wide range of conceptualizations used for generation of surface and subsurface runoff strongly affect runoff generation on seasonal, and shorter, time scales. Model responses to summer precipitation ranged from almost no summer runoff tone model) to the (more common) situation of persistent overprediction of summer runoff, especially in the driest part of the basin. (d) All models tended to underpredict evapotranspiration in summer and overpredict in winter. (e) Model-derived mean seasonal cycles of changes in soil moisture storage are qualitatively similar to those inferred from observations, but most models do not predict the decrease in April soil moisture storage and the increase in October that is inferred from observations. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Dept Civil Engn & Operat Res, Princeton, NJ 08544 USA. Univ Washington, Dept Civil Engn, Seattle, WA 98195 USA. NASA, Goddard Space Flight Ctr, Mesoscale Dynam & Precipitat Branch, Greenbelt, MD 20771 USA. USAF, Res Lab, Hanscom AFB, MA USA. NOAA, NCEP, Environm Modeling Ctr, Camp Springs, MD USA. Chinese Acad Sci, Inst Atmospher Phys, Beijing, Peoples R China. Macquarie Univ, Climat Impacts Ctr, Sydney, NSW 2109, Australia. Univ Arizona, Inst Atmospher Phys, Tucson, AZ USA. NOAA, Natl Weather Serv, Off Hydrol, Silver Spring, MD 20910 USA. Oregon State Univ, Corvallis, OR 97331 USA. Russian Acad Sci, Inst Water Problems, Moscow, Russia. Meteo France, CNRM, Toulouse, France. Univ New S Wales, Ctr Adv Numer Computat Engn & Sci, Sydney, NSW 2052, Australia. NASA, Goddard Space Flight Ctr, Hydrol Sci Branch, Greenbelt, MD 20771 USA. NOAA, GFDL, Princeton, NJ USA. Russian Acad Sci, Inst Geog, Moscow, Russia. Climate Res Branch, Atmospher Environm Serv, Toronto, ON, Canada. GKSS Forschungszentrum Geesthacht GmbH, Res Ctr, D-2054 Geesthacht, Germany. Ctr Ocean Land Atmospher Studies, Calverton, MD USA. RP Lohmann, D (reprint author), Princeton Univ, Dept Civil Engn & Operat Res, Princeton, NJ 08544 USA. RI Dai, Yongjiu/D-1070-2010; Dai, Yongjiu/D-6261-2014; Yang, Zong-Liang/B-4916-2011; Koster, Randal/F-5881-2012; Chen, Fei/B-1747-2009; lettenmaier, dennis/F-8780-2011; Nasonova, Olga/B-6093-2014; Duan, Qingyun/C-7652-2011; gusev, yugeniy/G-4711-2014; Shao, Yaping/G-3606-2013; OI Dai, Yongjiu/0000-0002-3588-6644; Habets, Florence/0000-0003-1950-0921; Koster, Randal/0000-0001-6418-6383; lettenmaier, dennis/0000-0003-3317-1327; Duan, Qingyun/0000-0001-9955-1512; gusev, yugeniy/0000-0003-3886-2143; Shao, Yaping/0000-0002-2041-5479; Wood, Eric/0000-0001-7037-9675 NR 25 TC 135 Z9 144 U1 0 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 EI 1872-6364 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD DEC PY 1998 VL 19 IS 1-4 BP 161 EP 179 DI 10.1016/S0921-8181(98)00046-0 PG 19 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 139GF UT WOS:000077019100010 ER PT J AU Heidler, JT AF Heidler, JT TI Women of the far right: The Mother's Movement and World War II. SO HISTORIAN LA English DT Book Review C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Heidler, JT (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU PHI ALPHA THETA PI ALLENTOWN PA THE HISTORIAN 50 COLLEGE DR, ALLENTOWN, PA 18104-6100 USA SN 0018-2370 J9 HISTORIAN JI Historian PD WIN PY 1998 VL 60 IS 2 BP 391 EP 392 PG 2 WC History SC History GA YY650 UT WOS:000072169800030 ER PT J AU Shebilske, WL Jordan, JA Goettl, BP Paulus, LE AF Shebilske, WL Jordan, JA Goettl, BP Paulus, LE TI Observation versus hands-on practice of complex skills in dyadic, triadic, and tetradic training-teams SO HUMAN FACTORS LA English DT Article ID INDIVIDUAL-DIFFERENCES; ACQUISITION; ABILITIES; PROTOCOLS; GAME AB We saved trainer time and resources by reducing hands-on practice in training-team protocols without reducing computer-based learning. During 1-h sessions, young adults learned Space Fortress, a video task that has been employed during pilot training. Observers (Experiment 1) learned more in 3 sessions than did test-only trainees. Individuals, dyads, triads, and tetrads (Experiment 2) learned in 3 sessions with no differences in learning or interaction between learning and protocol. Individuals, dyads, and tetrads (Experiment 3) learned in 10 sessions with no differences in learning or interaction between learning and protocol. As predicted by social learning theory, observational learning seems to compensate for hands-on practice efficiently and effectively. Applications of this research have been developed for computer-based group training of airline and air force pilots. C1 Texas A&M Univ, College Stn, TX 77843 USA. USAF, Res Lab, Brooks AFB, TX USA. RP Shebilske, WL (reprint author), Texas A&M Univ, College Stn, TX 77843 USA. NR 36 TC 11 Z9 11 U1 5 U2 5 PU HUMAN FACTORS SOC PI SANTA MONICA PA BOX 1369, SANTA MONICA, CA 90406 USA SN 0018-7208 J9 HUM FACTORS JI Hum. Factors PD DEC PY 1998 VL 40 IS 4 BP 525 EP 540 DI 10.1518/001872098779649319 PG 16 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 161KK UT WOS:000078287700001 ER PT J AU Colle, HA Reid, GB AF Colle, HA Reid, GB TI Context effects in subjective mental workload ratings SO HUMAN FACTORS LA English DT Article ID PERFORMANCE; SCALES AB The impact of performance context on subjective mental workload ratings was assessed with the Subjective Workload Assessment Technique (SWAT) and the NASA Task Load Index (TLX). In Experiment 1, a strong context effect was demonstrated. A low range of task difficulty produced considerably higher ratings on a common set of difficulty levels than did a high range of task difficulty. In Experiment 2, increasing the participants' range of experiences during practice eliminated the context effect. We recommend that methods for standardizing context, such as providing experience with the complete difficulty range, be developed for subjective mental workload evaluations. Actual or potential applications of this research include providing methodologies for controlling context effects in practical assessments of mental workload to increase the validity of subjective measures. C1 Wright State Univ, Dept Psychol, Dayton, OH 45435 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Colle, HA (reprint author), Wright State Univ, Dept Psychol, Dayton, OH 45435 USA. NR 16 TC 7 Z9 7 U1 2 U2 4 PU HUMAN FACTORS SOC PI SANTA MONICA PA BOX 1369, SANTA MONICA, CA 90406 USA SN 0018-7208 J9 HUM FACTORS JI Hum. Factors PD DEC PY 1998 VL 40 IS 4 BP 591 EP 600 DI 10.1518/001872098779649283 PG 10 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 161KK UT WOS:000078287700006 PM 9974231 ER PT J AU Noble, MJ Lott, JA Loehr, JP AF Noble, MJ Lott, JA Loehr, JP TI Quasi-exact optical analysis of oxide-apertured microcavity VCSEL's using vector finite elements SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE finite-element methods; laser modes; optical diffraction; semiconductor lasers; surface-emitting lasers ID DISTRIBUTED BRAGG REFLECTORS; FABRY-PEROT MICROCAVITY; SURFACE-EMITTING LASERS; VERTICAL-CAVITY LASERS; CONFINEMENT; EIGENMODE AB We report a new full vector finite element model for analyzing the optical properties of azimuthally symmetric oxide-apertured vertical-cavity surface-emitting lasers (VCSEL's), Our model allows for quasi-exact calculation of the lasing mode blueshift, threshold gain, and field profile. Through a detailed analysis of a sample VCSEL, we ascertain the physical effects which determine diffractive or parasitic mode loss. They are: 1) the background density of parasitic modes and 2) the coupling strength between the lasing mode and the parasitic mode continuum. The coupling strength is in turn determined by the relative alignment between the lasing and parasitic mode propagation vectors and the lasing mode penetration into the oxide region. This analysis improves our understanding of the optical physics of apertured VCSEL's and should enable the next leap down in lasing threshold. C1 USAF, Res Lab Sensors Directorate, AFRL, SNHC, Hanscom AFB, MA 01731 USA. USAF, Inst Technol, AFIT, ENG, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab Sensors Directorate, AFRL, SNDD, Wright Patterson AFB, OH 45433 USA. RP Noble, MJ (reprint author), USAF, Res Lab Sensors Directorate, AFRL, SNHC, Hanscom AFB, MA 01731 USA. NR 31 TC 21 Z9 21 U1 1 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD DEC PY 1998 VL 34 IS 12 BP 2327 EP 2339 DI 10.1109/3.736102 PG 13 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 140XG UT WOS:000077114500010 ER PT J AU Friedman, L Soref, RA Sun, G Lu, Y AF Friedman, L Soref, RA Sun, G Lu, Y TI Asymmetric strain-symmetrized Ge-Si interminiband laser SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article DE germanium; semiconductor lasers; silicon; superlattice AB We present analysis of a proposed Si-based GeSi superlattice p-i-p laser diode grown on a relaxed Si-0.25 Ge-0.75 buffer layer. Local-in-k-space population inversion between HH2 injector and HH1 minibands at the superlattice minizone boundary is predicted at the 4.6-mu m lasing wavelength. The 2.94-nm Ge well width is three times the 0.98-nm Si barrier width so there is no net strain. A dipole element \z(21)\ = 5.7 Angstrom is calculated, leading to an expected gain of 238 cm(-1) at an injection current density of 3 kA/cm(2), Issues such as the waveguide design, critical thicknesses, doping levels, and expected threhold current density are addressed. Further optimization of the design is required. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. Univ Massachusetts, Dept Phys, Boston, MA 02125 USA. RP Friedman, L (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 7 TC 6 Z9 6 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 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD DEC PY 1998 VL 10 IS 12 BP 1715 EP 1717 DI 10.1109/68.730479 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 140EL UT WOS:000077074100015 ER PT J AU Lehr, JM Agee, FJ Copeland, R Prather, WD AF Lehr, JM Agee, FJ Copeland, R Prather, WD TI Measurement of the electric breakdown strength of transformer oil in the sub-nanosecond regime SO IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION LA English DT Article ID DIELECTRIC LIQUIDS AB The dielectric strength of highly purified insulating transformer oil has been measured in the sub-nanosecond regime under single pulse and repetitive burst conditions. Single pulse breakdown fields have been measured to be 11 MV/cm. Repetitive bursts to 1 kHz reduce the threshold field value by a factor of two, with lower breakdown fields recorded at a 1.2 kHz repetition rate. The high-pressure hydrogen source provides a 130 ps risetime and al MV peak amplitude at repetition frequencies to 1.2 Hz. An experimental setup was used which permits the breakdown of the oil spark gap while protecting the high power source in case of total wave reflection, at the cost of excitation source fidelity. The breakdown electric fields are measured with self-integrating electric field sensors and an advanced diagnostic system which uses Fourier compensation to measure the fast risetime of the ultra-wideband pulse accurately. The anomalously high breakdown voltages measured with high power ultra-wideband sources compare favorably with Zheltov's prediction of the breakdown strength for sub-nanosecond pulse duration. The anomalously high field strengths permit the design of ultra wide band (UWB) high power microwave (HPM) sources with a reduced geometrical inductance which can result in significantly faster HPM UWB sources. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Lehr, JM (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 28 TC 24 Z9 32 U1 1 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1070-9878 J9 IEEE T DIELECT EL IN JI IEEE Trns. Dielectr. Electr. Insul. PD DEC PY 1998 VL 5 IS 6 BP 857 EP 861 DI 10.1109/94.740767 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 160AM UT WOS:000078208200007 ER PT J AU Vanheusden, K Fleetwood, DM Shaneyfelt, MR Draper, BL Schwank, JR AF Vanheusden, K Fleetwood, DM Shaneyfelt, MR Draper, BL Schwank, JR TI The effects of irradiation and proton implantation on the density of mobile protons in SiO2 thin films SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID MEMORY DEVICE; CENTERS; DEFECTS; WAFERS; CHARGE AB The radiation response of mobile protons introduced into thermal oxides capped with poly-Si is investigated. Total dose irradiation data show that the cross section for capture of radiation-induced electrons by mobile protons is two orders of magnitude smaller than for electron capture by trapped holes. A consistent model is proposed to explain the weak temperature dependence of the capture process observed in this study as opposed to the strong increase in proton neutralization with increasing temperature observed in an earlier UV exposure study. In contrast with the behavior of SOI material, no post-irradiation trapping of mobile protons could be observed in the thermal SiO2 layer of the Si/SiO2/Si structures studied in this work. In the second part of this work it is shown that, unlike the effect of annealing in a hydrogen containing ambient, proton implantation does not yield a significant number of mobile protons in the buried oxide of Si/SiO2/Si structures. C1 USAF, Res Lab, Space Elect & Protect Branch VSSE, Kirtland AFB, NM 87117 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vanheusden, K (reprint author), USAF, Res Lab, Space Elect & Protect Branch VSSE, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 25 TC 9 Z9 9 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2391 EP 2397 DI 10.1109/23.736459 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200011 ER PT J AU Karna, SP Pugh, RD Chavez, JR Shedd, W Brothers, CP Singaraju, BK Vitiello, M Pacchioni, G Devine, RA AF Karna, SP Pugh, RD Chavez, JR Shedd, W Brothers, CP Singaraju, BK Vitiello, M Pacchioni, G Devine, RA TI Microscopic mechanisms of radiation-induced proton density decay in SiO2 films SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID THIN-FILMS AB In order to understand the physics of radiation-induced proton density decay in thin SiO2 films, we performed ab initio Hartree-Fock calculations of the potential energy curves for the interaction between model oxide clusters and H in two charge states. The calculated results led to two separate proposed mechanisms for proton density decay in thin SiO2 films: (1) electronic excitation involving hot phonon levels of the ground electronic state at low photon-energy radiation and (2) electron capture by protons at high photon-energy radiation. The proposed mechanisms qualitatively explain recent experimental observations. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. Univ Milan, Dipartimento Sci Mat, I-20126 Milan, Italy. France Telecom, Ctr Natl Etud Telecommun, F-38243 Meylan, France. RP Karna, SP (reprint author), USAF, Res Lab, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. RI Pacchioni, Gianfranco/C-8529-2011 OI Pacchioni, Gianfranco/0000-0002-4749-0751 NR 14 TC 13 Z9 13 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2408 EP 2412 DI 10.1109/23.736479 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200013 ER PT J AU Schone, H Walsh, DS Sexton, FW Doyle, BL Dodd, PE Aurand, JF Flores, RS Wing, N AF Schone, H Walsh, DS Sexton, FW Doyle, BL Dodd, PE Aurand, JF Flores, RS Wing, N TI Time-resolved ion beam induced charge collection (TRIBICC) in micro-electronics SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID TRANSIENTS; DAMAGE AB The entire current transient induced by single 12-MeV Carbon ions was measured at a 5GHz analog bandwidth. A focused ion micro-beam was used to acquire multiple single ion transients at multiple locations of a single CMOS transistor. The current transients reveal clear and discernible contributions of drift and diffusive charge collection. Transients measured for drain and off-drain ion strikes compare well to 3D DAVINCI calculations. The simulations match the drift charge collection measurements within experimental errors. Estimates are presented for the drift assisted funneling charge collection depth. C1 USAF, Res Lab, VSSE, Albuquerque, NM 87117 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Schone, H (reprint author), USAF, Res Lab, VSSE, 3550 Aberdeen Ave, Albuquerque, NM 87117 USA. NR 12 TC 29 Z9 29 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2544 EP 2549 DI 10.1109/23.736496 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200030 ER PT J AU Turinetti, JR Kemp, WT Chavez, JR AF Turinetti, JR Kemp, WT Chavez, JR TI Spectrum determination and modification of the AFRL Co-60 cell SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID CODE AB The spectrum of a Co-60 facility includes more than the two photopeaks of gamma ray emission. If there is a large low energy contribution from scattering, dose enhancement might be a problem. It is important to know the spectrum of a Co-60 facility and understand how experimental modifications can change that spectrum. The AFRL Co-60 cell spectrum is found to be a clean spectrum with small low energy contributions and dominant Co-60 photopeaks. Experimental modifications to reduce dose enhancement such as the use of a Pb/Al box and even better a Pb/Sn/Cu/Al box are found to decrease the low energy contributions. Experimental modifications to reduce dose rate such as using lead attenuators in front of the experiment and/or raising the source partially are found to significantly alter the spectrum, sometimes creating large low energy contributions. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Turinetti, JR (reprint author), USAF, Res Lab, 3550 Aberdeen Ave, Kirtland AFB, NM 87117 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2720 EP 2726 DI 10.1109/23.736520 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200053 ER PT J AU Spieth, BD Qassim, KS Pittman, RN Russell, DA AF Spieth, BD Qassim, KS Pittman, RN Russell, DA TI Shielding electronics behind composite structures SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm AB The increasing use of composite structures and composite electronics boxes in space can result in a several-fold increase in electronics radiation total dose, as compared to using aluminum structures and aluminum electronics boxes. There are also desires to use Multi-Function Structures. (MFS), where electronics are integral with composite structures (no electronics boxes). MFS approaches can result in an order of magnitude increase in radiation dose to electronics over conventional aluminum structures and boxes. The designer must either use rad-hard parts which are becoming more difficult to obtain since the end of the Cold War, increase spot shielding, use RADPAK(TM) [1] solutions, or add shielding to composite boxes and structures. With the increasing use of low hardness commercial parts to reduce costs, a brute force solution of adding shielding to composite boxes is frequently the lowest cost solution. Analyses, test data, and a flight experiment are described to assess these shielding options. C1 ITN Energy Syst 303 4201141, Wheat Ridge, CO 80033 USA. USAF, Res Lab, VSDV, Kirtland AFB, NM 87117 USA. Boeing Informat Space & Def Syst, Seattle, WA 98108 USA. RP Spieth, BD (reprint author), ITN Energy Syst 303 4201141, 12401 W 49th Ave, Wheat Ridge, CO 80033 USA. NR 11 TC 3 Z9 3 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2752 EP 2757 DI 10.1109/23.736524 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200057 ER PT J AU Dichter, BK McGarity, JO Oberhardt, MR Jordanov, VT Sperry, DJ Huber, AC Pantazis, JA Mullen, EG Ginet, G Gussenhoven, MS AF Dichter, BK McGarity, JO Oberhardt, MR Jordanov, VT Sperry, DJ Huber, AC Pantazis, JA Mullen, EG Ginet, G Gussenhoven, MS TI Compact Environmental Anomaly Sensor (CEASE): A novel spacecraft instrument for in situ measurements of environmental conditions SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID ELECTROSTATIC DISCHARGES; DOSE MEASUREMENTS; CRRES; SATELLITE AB A small. lightweight, and low power, spacecraft instrument, CEASE, has been designed to measure the local space radiation environment. The instrument's on-board processing algorithms use the collected data to generate warnings of the space environment hazards of radiation damage. dielectric charging and single event effects (SEE). Ln addition. CEASE can provide detailed space environment data to aid in analysis of anomalies that may occur on the host spacecraft. C1 Amptek Inc, Bedford, MA 01730 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Dichter, BK (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 10 TC 19 Z9 19 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 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2758 EP 2764 DI 10.1109/23.736525 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200058 ER PT J AU Mullen, EG Ginet, G Gussenhoven, MS Madden, D AF Mullen, EG Ginet, G Gussenhoven, MS Madden, D TI SEE relative probability maps for space operations SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID RADIATION BELT PARTICLES; CRRES AB Normalized flux and dose data for protons with energies >50 MeV are used to produce contour maps of relative probabilities of experiencing Single Event Effects (SEEs) in the Earth's inner radiation belt. The data were taken on the APEX and CRRES satellites. To make the maps, the data are averaged in 3 degrees by 3 degrees bins in geographic latitude and longitude, and in 50 km steps in altitude. All geographic longitudes, and latitudes between less than or equal to 70 degrees are covered. The altitude range extends from 350 km to 14,000 km. This geographic range includes the complete region of inner belt >50 MeV protons, except in the area of the South Atlantic Anomaly below 350 km. The maps easily locate regions of high risk for SEEs and are designed primarily for use in space mission planning and operations. The data base includes the added proton peak following the March 1991 magnetic storm, but does not include SEE probabilities in the polar cap regions associated with high energy solar particle events. C1 Assurance Technol Corp, Carlisle, MA 01741 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. Boston Coll, Inst Sci Res, Newton, MA 02159 USA. RP Mullen, EG (reprint author), Assurance Technol Corp, Carlisle, MA 01741 USA. NR 25 TC 4 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2954 EP 2963 DI 10.1109/23.736552 PN 1 PG 10 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200085 ER PT J AU Narayanan, S Malu, PG Ashili, KPB Di Pasquale, J Carrico, TM AF Narayanan, S Malu, PG Ashili, KPB Di Pasquale, J Carrico, TM TI A web-based interactive simulation architecture for airbase logistics systems analysis SO INTERNATIONAL JOURNAL OF INDUSTRIAL ENGINEERING-THEORY APPLICATIONS AND PRACTICE LA English DT Article DE interactive simulation; Internet; distributed computing; logistics modeling; CORBA ID OBJECT-ORIENTED SIMULATION; MANUFACTURING SYSTEMS AB Portable interactive simulations that support concurrent multi-user interaction are useful in the analysis of large and semistructured problems especially those in which human interaction are of important consideration. Emerging concepts in distributed computing provide enabling technologies for the development of flexible and portable interactive simulation infrastructure. This article describes an object-based interactive simulation architecture, through which multiple users can interact concurrently with an executing simulation from distributed locations. The simulation executes on a server and users can connect in to the simulation and provide user commands through interfaces implemented as separate processes. This article describes the architectural components and demonstrates application in a real-world problem in the domain of airbase logistics. This paper also presents an evaluation of the effectiveness of various means of facilitating communication between interfaces and the simulation process including the use of Java application programming through sockets, Java programs integrated with Common Object Request Broker Architecture technology, and Java's remote method invocation protocol. C1 Wright State Univ, Coll Engn & Comp Sci, Russ Engn Ctr 207, Dayton, OH 45435 USA. USAF, Res Lab, HESR, Wright Patterson AFB, OH 45433 USA. Def Adv Res Projects Agcy, Arlington, VA USA. RP Narayanan, S (reprint author), Wright State Univ, Coll Engn & Comp Sci, Russ Engn Ctr 207, Dayton, OH 45435 USA. NR 27 TC 2 Z9 2 U1 1 U2 1 PU UNIV CINCINNATI INDUSTRIAL ENGINEERING PI CINCINNATI PA UNIV CINCINNATI, CINCINNATI, OH 45221-0116 USA SN 1072-4761 J9 INT J IND ENG-THEORY JI Int. J. Ind. Eng.-Theory Appl. Pract. PD DEC PY 1998 VL 5 IS 4 BP 324 EP 335 PG 12 WC Engineering, Industrial; Engineering, Manufacturing SC Engineering GA 160VB UT WOS:000078251100008 ER PT J AU Yepez, J AF Yepez, J TI Lattice-gas quantum computation SO INTERNATIONAL JOURNAL OF MODERN PHYSICS C LA English DT Article; Proceedings Paper CT 7th International Conference on the Discrete Simulation of Fluids CY JUL 14-18, 1998 CL UNIV OXFORD, OXFORD, ENGLAND HO UNIV OXFORD DE quantum lattice-gas; quantum computing; lattice-gas automata; Navier-Stokes fluids; computational fluid dynamics; parallel computing ID NAVIER-STOKES EQUATION; SCHRODINGER-EQUATION; AUTOMATA; MODELS AB We present a quantum lattice-gas model for a quantum computer operating with continual wavefunction collapse; entanglement of the wavefunction occurs locally over small spatial regions between nearby qubits for only a short time period. The quantum lattice-gas is a noiseless method that directly models the lattice-gas particle dynamics at the mesoscopic scale. The system behaves like a viscous Navier-Stokes fluid. Numerical simulations indicate the viscosity of the quantum lattice-gas fluid is lower than its classical lattice-gas counterpart's. C1 USAF, Res Lab, Hanscom Field, MA 01731 USA. RP Yepez, J (reprint author), USAF, Res Lab, Hanscom Field, MA 01731 USA. NR 13 TC 33 Z9 33 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0129-1831 J9 INT J MOD PHYS C JI Int. J. Mod. Phys. C PD DEC PY 1998 VL 9 IS 8 BP 1587 EP 1596 DI 10.1142/S0129183198001436 PG 10 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 199BL UT WOS:000080459500041 ER PT J AU Kokoska, ER Stapleton, DR Virgo, KS Johnson, FE Wade, TP AF Kokoska, ER Stapleton, DR Virgo, KS Johnson, FE Wade, TP TI Quality of life measurements do not support palliative pancreatic cancer treatments SO INTERNATIONAL JOURNAL OF ONCOLOGY LA English DT Article DE pancreatic cancer; quality of life; palliation; surgery; radiation therapy; chemotherapy ID KARNOFSKY PERFORMANCE STATUS; OF-LIFE; STATUS SCALE; SURVIVAL; RESECTION; ADENOCARCINOMA; PANCREATICODUODENECTOMY; CARCINOMA; RELIABILITY; VALIDITY AB Although resection for pancreatic cancer is occasionally curative, its major value lies in restoring patients to a more normal life. The objective of this study was to evaluate the functional quality of life (QoL) of patients undergoing various treatments for pancreatic cancer using a nationwide, multi-institutional, non-referral patient population. From 822 pancreatic cancer patients treated from 1989 to 1995, and listed in the Department of Defense (DoD) hospital central computerized tumor registry, we selected 781 with evaluable survival information. Local tumor registrars had contacted patients at least yearly and prospectively compiled a QoL index using a self-reported Karnofsky performance status (KPS); values were obtained for patients alive in March of 1995 and/or 1996. Survival duration and KPS scores were then compared by stage and treatment using analysis of variance (F-test). Resection significantly increased KPS and mean survival time with stage I-II cancers and improved mean survival time, but not KPS, in patients with node positive (stage III) disease. The projected five-year survival rate after resection in stages I-II was 24% but zero for stage III. Patients receiving combined chemo- and radiation therapies, whether given as adjuvant or primary treatment, had significantly longer mean survival duration. However, KPS scores were not higher in treated patients. These data indicate that patients live longer and better lives after resection of localized pancreatic cancers, but QoL measurements do not support resection for pancreatic cancer involving lymph nodes. Unresected patients selected for combined chemo- and radiation therapy live longer, but not better, lives. C1 St Louis Univ, Hlth Sci Ctr, Dept Surg, St Louis, MO 63110 USA. USAF, Med Ctr, Canc Comm & Tumor Registry, Scott AFB, IL USA. RP Johnson, FE (reprint author), St Louis Univ, Hlth Sci Ctr, Dept Surg, POB 15250,3635 Vista Ave & Grand Blvd, St Louis, MO 63110 USA. NR 33 TC 9 Z9 9 U1 0 U2 0 PU PROFESSOR D A SPANDIDOS PI ATHENS PA 1, S MERKOURI ST, EDITORIAL OFFICE,, ATHENS 116 35, GREECE SN 1019-6439 J9 INT J ONCOL JI Int. J. Oncol. PD DEC PY 1998 VL 13 IS 6 BP 1323 EP 1329 PG 7 WC Oncology SC Oncology GA 143YF UT WOS:000077284600036 PM 9824652 ER PT J AU Carpenter, MT Hugler, R Enzenauer, RJ Des Rosier, KF Kirk, JM Brehm, WT AF Carpenter, MT Hugler, R Enzenauer, RJ Des Rosier, KF Kirk, JM Brehm, WT TI Physical and sexual abuse in female patients with fibromyalgia SO JCR-JOURNAL OF CLINICAL RHEUMATOLOGY LA English DT Article DE physical abuse; sexual abuse; fibromyalgia ID WOMEN; HEALTH; INPATIENTS; PREVALENCE; DISORDERS; VIOLENCE; HISTORY; LIFE AB Sexual and physical abuse during childhood seem to be common. The purpose of this study was to determine the prevalence of sexual and physical abuse reported by female fibromyalgia (FM) patients in a referral-based rheumatology practice, and whether patients with FM report greater frequencies of abuse than do patients with rheumatoid arthritis (RA). Patients from two tertiary care centers, 205 with FM and 84 with RA, were mailed a self-administered questionnaire requesting information about demographics, mental health care use, and history of sexual and/or physical abuse. There were responses from 105 FM and 44 RA patients. A history of sexual or physical abuse was reported by 54% of the sample. Any type of abuse was significantly more prevalent among patients with FM (62%) compared with those with RA (34%, p = 0.02). FM patients had a significantly increased prevalence of both sexual abuse (51% vs. 32%, p = 0.028) and physical abuse (39 vs. 16%, p = 0.006) compared with RA patients. FM patients were more likely than RA patients to report a history of multiple sexual abusers, increased duration of sexual abuse, and more violent physical abuse. Irritable bowel syndrome was more common in FM (44%) than RA patients (9%, p < 0.001), and 57% of FM patients had seen a mental health professional compared with 30% of RA patients (p = 0.002). These data suggest that sexual or physical abuse is a frequently reported experience in FM patients. An inquiry about sexual or physical abuse should be considered in female patients with FM. Prospective studies are needed to determine whether psychological treatment of sexually abused FM patients will decrease symptoms and healthcare use. C1 Wilford Hall USAF Med Ctr, Dept Rheumatol, Lackland AFB, TX 78236 USA. Fitzsimons Army Med Ctr, Rheumatol Serv, Aurora, CO 80045 USA. USA, Psychiat Serv, White Sands Missile Rang, NM USA. 81st Med Grp, Clin Res Lab, Keesler AFB, MS USA. RP Carpenter, MT (reprint author), SGOM, MDOS 81, 301 Fisher St,Room 1A132, Keesler AFB, MS 39534 USA. NR 28 TC 10 Z9 10 U1 1 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1076-1608 J9 JCR-J CLIN RHEUMATOL JI JCR-J. Clin. Rheumatol. PD DEC PY 1998 VL 4 IS 6 BP 301 EP 306 DI 10.1097/00124743-199812000-00002 PG 6 WC Rheumatology SC Rheumatology GA 151LN UT WOS:000077721700002 PM 19078326 ER PT J AU Knighton, WB Miller, TM Viggiano, AA Morris, RA Van Doren, VM AF Knighton, WB Miller, TM Viggiano, AA Morris, RA Van Doren, VM TI Gas-phase reactions of oxide and superoxide radical anions with C6F6 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ION C1 Montana State Univ, Dept Chem & Biochem, Bozeman, MT 59717 USA. USAF, Res Lab, Space Vehicles Directorate VSBP, Bedford, MA 01731 USA. Coll Holy Cross, Dept Chem, Worcester, MA 01610 USA. RP Knighton, WB (reprint author), Montana State Univ, Dept Chem & Biochem, Bozeman, MT 59717 USA. NR 12 TC 3 Z9 3 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1998 VL 109 IS 21 BP 9632 EP 9633 DI 10.1063/1.477625 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 141MN UT WOS:000077147900047 ER PT J AU Clements-Thompson, M Klesges, RC Haddock, K Lando, H Talcott, W AF Clements-Thompson, M Klesges, RC Haddock, K Lando, H Talcott, W TI Relationships between stages of change in cigarette smokers and healthy lifestyle behaviors in a population of young military personnel during forced smoking abstinence SO JOURNAL OF CONSULTING AND CLINICAL PSYCHOLOGY LA English DT Article ID TRANSTHEORETICAL MODEL; CESSATION AB This study evaluated the relationships between stages of change and related health behaviors in a population of smokers forced to quit smoking. Participants were 10,136 Air Force recruits who were in basic military training (BMT) and who were not allowed to smoke because of a ban on smoking during BMT. Participants were surveyed about their smoking history, their motivation and readiness to remain smoke free after BMT, and their behavior on 5 target health areas. Results indicated that smoking history best predicted stage of change. Though there were few gender differences, several ethnic differences emerged. These results suggest that, although stages of change involve both a cognitive and behavioral component, removing the behavioral component (smoking) through a smoking ban does not reduce the construct validity of the transtheoretical model. C1 Univ Memphis, Prevent Ctr, Dept Psychol, Memphis, TN 38119 USA. Univ Missouri, Dept Psychol, Kansas City, MO 64110 USA. Univ Minnesota, Sch Publ Hlth, Minneapolis, MN 55455 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Klesges, RC (reprint author), Univ Memphis, Prevent Ctr, Dept Psychol, Memphis, TN 38119 USA. FU NHLBI NIH HHS [HL-53478] NR 12 TC 14 Z9 14 U1 0 U2 1 PU AMER PSYCHOLOGICAL ASSOC PI WASHINGTON PA 750 FIRST ST NE, WASHINGTON, DC 20002-4242 USA SN 0022-006X J9 J CONSULT CLIN PSYCH JI J. Consult. Clin. Psychol. PD DEC PY 1998 VL 66 IS 6 BP 1005 EP 1011 DI 10.1037//0022-006X.66.6.1005 PG 7 WC Psychology, Clinical SC Psychology GA 151DU UT WOS:000077706100014 PM 9874914 ER PT J AU Stutz, CE AF Stutz, CE TI Photoelectrochemical capacitance-voltage measurements of 4H-SiC SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Letter DE 4H-SiC; photoelectrochemical capacitance-voltage (PC-V) measurements; secondary ion mass spectroscopy (SIMS) AB Photoelectrochemical capacitance-voltage (PC-V) measurements have been successfully made on 4H-SiC material. The 0.05 MKOH solution used as a Schottky contact etches the material with an average roughness of about one percent of the total average etch depth at an etch rate of 1 mu m/h. This capability allows the carrier concentration profile of thicker layers with different doping levels to be analyzed. The PC-V measurements are compared with secondary ion mass spectroscopy. The results show agreement with nitrogen doping in the top epitaxial layer and in the substrate. The PC-V measurement also sees an unknown species diffusing out of the substrate into the nominally undoped buffer layer. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Stutz, CE (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 7 TC 11 Z9 11 U1 1 U2 7 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD DEC PY 1998 VL 27 IS 12 BP L81 EP L83 DI 10.1007/s11664-998-0101-8 PG 3 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 146PW UT WOS:000077440400017 ER PT J AU Graham, CW Lynch, SC Muskat, PC Mokulis, JA AF Graham, CW Lynch, SC Muskat, PC Mokulis, JA TI Laparoscopic evacuation of a subcapsular renal hematoma causing symptomatic hypertension SO JOURNAL OF ENDOUROLOGY LA English DT Article ID SHOCK-WAVE LITHOTRIPSY; RENIN AB We report the case of a subcapsular hematoma following extracorporeal shockwave lithotripsy which presented as symptomatic hypertension. When medical therapy proved ineffective, laparoscopic decompression of the hematoma corrected the hypertension. C1 Wilford Hall USAF Med Ctr, Dept Urol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Gen Surg, Lackland AFB, TX 78236 USA. RP Graham, CW (reprint author), NE Med Ctr, 8711 Village Dr,312, San Antonio, TX 78217 USA. NR 5 TC 4 Z9 4 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0892-7790 J9 J ENDOUROL JI J. Endourol. PD DEC PY 1998 VL 12 IS 6 BP 551 EP 553 DI 10.1089/end.1998.12.551 PG 3 WC Urology & Nephrology SC Urology & Nephrology GA 155LN UT WOS:000077948600013 PM 9895261 ER PT J AU Baldwin, TD Stinson, J Ham, RK AF Baldwin, TD Stinson, J Ham, RK TI Decomposition of specific materials buried within sanitary landfills SO JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE LA English DT Article AB Eleven samples of typical solid waste components, ranging from high to low predicted degradability, were analyzed prior to burial within three landfills representing different climates. Sets of these samples were retrieved periodically over 6 years and analyzed for changes in moisture content, dry weight, cellulose (holocellulose), and lignin. Results were that carbohydrates such as cellulose (holocellulose) and starch were the quickest degrading portions of the waste, and the samples with high lignin contents degraded more slowly than those samples with lower lignin contents. Finally, degradation was found to increase with higher moisture contents and higher temperatures. The uniqueness of this research is that it was performed in full-scale landfills, yet having baseline values for the samples. C1 NC Dept Envir & Nat Resour, Raleigh, NC 27609 USA. USAF, AL EQW OL, Tyndall AFB, FL 32403 USA. Univ Wisconsin, Dept Civ & Envir Engrg, Madison, WI 53706 USA. RP Baldwin, TD (reprint author), NC Dept Envir & Nat Resour, 3800 Barrett Dr, Raleigh, NC 27609 USA. NR 5 TC 16 Z9 17 U1 2 U2 6 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 USA SN 0733-9372 J9 J ENVIRON ENG-ASCE JI J. Environ. Eng.-ASCE PD DEC PY 1998 VL 124 IS 12 BP 1193 EP 1202 DI 10.1061/(ASCE)0733-9372(1998)124:12(1193) PG 10 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 139AX UT WOS:000077006200009 ER PT J AU Ma, N Walker, J Bliss, D Bryant, G AF Ma, N Walker, J Bliss, D Bryant, G TI Forced convection during liquid encapsulated crystal growth with an axial magnetic field SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID CZOCHRALSKI PROCESS; OXYGEN SEGREGATION; BUOYANT CONVECTION; ISOTHERMAL MOTION; MELT MOTION; LEC GAAS; SILICON; PULLER; TEMPERATURE; SIMULATION AB This paper treats the forced convection, which is produced by the rotation of the crystal about its vertical centerline during the liquid-encapsulated Czochralski or Kyropoulos growth of compound semiconductor crystals, with a uniform vertical magnetic field. The model assumes that the magnetic field strength is sufficiently large that convective heat transfer and all inertial effects except the centripetal acceleration are negligible. With the liquid encapsulant in the radial gap between the outside surface of the crystal and the vertical wall of the crucible, the forced convection is fundamentally different from that with a free surface between the crystal and crucible for the Czochralski growth of silicon crystals. Again unlike the case for silicon growth, the forced convection for the actual nonzero electrical conductivity of an indium-phosphide crystal is virtually identical to that for an electrically insulating crystal. The electromagnetic damping of the forced convection is stronger than that of the buoyant convection In order to maintain a given balance between the forced and buoyant convections, the angular velocity of the crystal must be increased as the magnetic field strength is increased. C1 Univ Missouri, Dept Mech & Aerosp Engn & Engn Mech, Rolla, MO 65409 USA. Univ Illinois, Dept Mech & Ind Engn, Urbana, IL 61801 USA. USAF, Rome Lab, Hanscom AFB, MA 01731 USA. RP Ma, N (reprint author), Univ Missouri, Dept Mech & Aerosp Engn & Engn Mech, Rolla, MO 65409 USA. NR 19 TC 8 Z9 8 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD DEC PY 1998 VL 120 IS 4 BP 844 EP 850 DI 10.1115/1.2820749 PG 7 WC Engineering, Mechanical SC Engineering GA 151ZB UT WOS:000077749700032 ER PT J AU Hofstraat, H Eastwood, D AF Hofstraat, H Eastwood, D TI Special topic: Selected papers from the Luminescence Symposium, 24th Annual Conference of the Federation of Analytical Chemistry and Spectroscopy Studies, Providence, Rhode Island, October 29-30, 1997 - Introduction SO JOURNAL OF FLUORESCENCE LA English DT Editorial Material C1 Philips Res, Eindhoven, Netherlands. USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Hofstraat, H (reprint author), Philips Res, Eindhoven, Netherlands. NR 0 TC 0 Z9 0 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1053-0509 J9 J FLUORESC JI J. Fluoresc. PD DEC PY 1998 VL 8 IS 4 BP 281 EP 281 DI 10.1023/A:1020504011170 PG 1 WC Biochemical Research Methods; Chemistry, Analytical; Chemistry, Physical SC Biochemistry & Molecular Biology; Chemistry GA 242DM UT WOS:000082923000001 ER PT J AU Burke, WJ Maynard, NC Hagan, MP Wolf, RA Wilson, GR Gentile, LC Gussenhoven, MS Huang, CY Garner, TW Rich, FJ AF Burke, WJ Maynard, NC Hagan, MP Wolf, RA Wilson, GR Gentile, LC Gussenhoven, MS Huang, CY Garner, TW Rich, FJ TI Electrodynamics of the inner magnetosphere observed in the dusk sector by CRRES and DMSP during the magnetic storm of June 4-6, 1991 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ZONAL ELECTRIC-FIELDS; TIME RING CURRENT; QUANTITATIVE SIMULATION; CONVECTION PATTERNS; DISTURBANCE DYNAMO; EMPIRICAL-MODELS; SUBSTORM; MAGNETOPAUSE; PENETRATION; INSTRUMENT AB We compare equatorward/earthward boundaries of convection electric fields and auroral/plasma sheet electrons detected by the DMSP F8 and CRRES satellites during the June 1991 magnetic storm. Measurements come from the dusk magnetic local time sector where the ring current penetrates closest to the Earth. The storm was triggered by a rapid increase in the solar wind dynamic pressure accompanied by a southward turning of the interplanetary magnetic field (IMF). Satellite data show the following: (1) All particle and field boundaries moved equatorward/earthward during the initial phase, probably in response to the strong southward IMF turning. (2) Electric field boundaries were either at lower magnetic L shells or close to the inner edge of ring current ions throughout the main and early recovery phases. Penetration earthward of the ring current occurred twice as the polar cap potential increased rapidly. (3) Electric potentials at subauroral latitudes were large fractions of the total potentials in the afternoon cell, twice exceeding 60 kV. (4) The boundaries of auroral electron precipitation were more variable than those of electric fields and mapped to lower I; shells than where CRRES encountered plasma sheet electrons. Observations qualitatvely agree with predictions of empirical models for auroral electron and electric field boundaries. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA. Mission Res Corp, Nashua, NH 03062 USA. Rice Univ, Dept Space Phys & Astron, Houston, TX 77005 USA. RP Burke, WJ (reprint author), USAF, Res Lab, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 46 TC 72 Z9 73 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1998 VL 103 IS A12 BP 29399 EP 29418 DI 10.1029/98JA02197 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 149MD UT WOS:000077608400023 ER PT J AU Heppard, KA Miles, RE AF Heppard, KA Miles, RE TI High expectations, supportiveness, and the management hall of fame - A conversation with Raymond E. Miles SO JOURNAL OF MANAGEMENT INQUIRY LA English DT Editorial Material ID NETWORK ORGANIZATIONS; FAILURE; FORMS; FIT C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Heppard, KA (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 21 TC 0 Z9 0 U1 0 U2 1 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1056-4926 J9 J MANAGE INQUIRY JI J. Manage. Inq. PD DEC PY 1998 VL 7 IS 4 BP 294 EP 304 DI 10.1177/105649269874003 PG 11 WC Management SC Business & Economics GA 142XM UT WOS:000077225800003 ER PT J AU Lowe, DT AF Lowe, DT TI Comment on recent symposium overview: Does excess dietary protein adversely affect bone SO JOURNAL OF NUTRITION LA English DT Letter ID L-ARGININE; NITRIC-OXIDE; PATHWAY C1 USAF, 375th Med Grp, Scott AFB, IL 62225 USA. RP Lowe, DT (reprint author), USAF, 375th Med Grp, Scott AFB, IL 62225 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU AMER INST NUTRITION PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-3166 J9 J NUTR JI J. Nutr. PD DEC PY 1998 VL 128 IS 12 BP 2529 EP 2529 PG 1 WC Nutrition & Dietetics SC Nutrition & Dietetics GA 148UV UT WOS:000077552500034 PM 9868205 ER PT J AU Hendrix, WH Robbins, T Miller, J Summers, TP AF Hendrix, WH Robbins, T Miller, J Summers, TP TI Effects of procedural and distributive justice on factors predictive of turnover SO JOURNAL OF SOCIAL BEHAVIOR AND PERSONALITY LA English DT Article ID GROUP-VALUE MODEL; ORGANIZATIONAL COMMITMENT; PERCEIVED FAIRNESS; EMPLOYEE TURNOVER; JOB-SATISFACTION; PERFORMANCE EVALUATION; CITIZENSHIP BEHAVIOR; OUTCOMES; ANTECEDENTS; PAY AB The purpose of this research was to develop and test a model linking justice perceptions to a series of variables leading to turnover. Confirmatory and exploratory path analyses were performed to identify primary paths from procedural and distributive justice perceptions to job satisfaction, organizational commitment, work group performance, attendance motivation, turnover intentions, and in turn, turnover. Results indicated that positive procedural and distributive justice perceptions were associated with increased intrinsic and extrinsic job satisfaction, and organizational commitment. Procedural justice perceptions were positively related to perceptions of work group performance. Distributive justice perceptions were negatively related to turnover intentions. Actual turnover was directly influenced by only one factor, turnover intentions, and indirectly by all variables in the model except for work group performance perceptions and extrinsic job satisfaction. C1 USAF Acad, Dept Behav Sci & Leadership, HQ USAFA, DFBL, Colorado Springs, CO 80840 USA. Clemson Univ, Clemson, SC 29631 USA. RP Hendrix, WH (reprint author), USAF Acad, Dept Behav Sci & Leadership, HQ USAFA, DFBL, 2354 Fairchild Dr,Suite 6L47, Colorado Springs, CO 80840 USA. NR 77 TC 45 Z9 45 U1 1 U2 19 PU SELECT PRESS PI CORTE MADERA PA PO BOX 37, CORTE MADERA, CA 94976 USA SN 0886-1641 J9 J SOC BEHAV PERS JI J. Soc. Behav. Pers. PD DEC PY 1998 VL 13 IS 4 BP 611 EP 632 PG 22 WC Psychology, Social SC Psychology GA 191WU UT WOS:000080045200004 ER PT J AU Corum, JS AF Corum, JS TI The German campaign in Norway 1940 as a joint operation SO JOURNAL OF STRATEGIC STUDIES LA English DT Article AB The German invasion in Norway in April 1940 was unique in that it was the first major 'triphibious' campaign. It was an operation that was equally dependent upon naval, air and ground forces for success. Norway had long been of interest to German strategists, especially naval thinkers. However, no serious Wehrmacht plans for occupying Norway were even started until December 1939. A small group of staff officers of the three services put together a comprehensive plan in a matter of weeks. The article examines the effectiveness of the German interservice co-operation and OKW leadership in a very tough and close run campaign. Although there were numerous problems, interservice co-operation was fairly effective at the tactical and operational levels. Indeed, the Germans won the campaign largely because their services worked together much better than their Allied opponents. C1 USAF, Sch Adv Airpower Studies, Maxwell AFB, AL USA. RP Corum, JS (reprint author), USAF, Sch Adv Airpower Studies, Maxwell AFB, AL USA. NR 36 TC 1 Z9 1 U1 0 U2 0 PU FRANK CASS CO LTD PI ESSEX PA NEWBURY HOUSE, 900 EASTERN AVE, NEWBURY PARK, ILFORD, ESSEX IG2 7HH, ENGLAND SN 0140-2390 J9 J STRATEGIC STUD JI J. Strateg. Stud. PD DEC PY 1998 VL 21 IS 4 BP 50 EP 77 DI 10.1080/01402399808437735 PG 28 WC International Relations; Political Science SC International Relations; Government & Law GA 183YX UT WOS:000079583500003 ER PT J AU Allen, RW AF Allen, RW TI Britain revives the Belgian Army 1940-45 SO JOURNAL OF STRATEGIC STUDIES LA English DT Article AB The British provided unprecedented shelter, training and supplies that made possible the revival of a new and better Belgian Army after the crushing German victories in 1940. Starting in Wales in 1940 as a small and disunited group, the Belgians improved more than any of the Allied exile ground forces. By 1944, their independent brigade fought well in Normandy and Belgium, restoring national pride and proving the worth of British help. The parallel and interdependent processes between the British and their Continental guests allows this analysis of the Anglo-Belgian experience to be useful in considering British Army interactions with the other exiles as well. C1 USAF, Lackland AFB, TX 78236 USA. NR 39 TC 2 Z9 2 U1 0 U2 0 PU FRANK CASS CO LTD PI ESSEX PA NEWBURY HOUSE, 900 EASTERN AVE, NEWBURY PARK, ILFORD, ESSEX IG2 7HH, ENGLAND SN 0140-2390 J9 J STRATEGIC STUD JI J. Strateg. Stud. PD DEC PY 1998 VL 21 IS 4 BP 78 EP 96 DI 10.1080/01402399808437736 PG 19 WC International Relations; Political Science SC International Relations; Government & Law GA 183YX UT WOS:000079583500004 ER PT J AU Cinibulk, MK AF Cinibulk, MK TI Effect of precursors and dopants on the synthesis and grain growth of calcium hexaluminate SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID BOEHMITE-DERIVED ALUMINA; LIQUID-PHASE; BOUNDARY SEGREGATION; SINTERED ALUMINA; SOLID-SOLUTIONS; AL2O3; OXIDE; TRANSFORMATION; KINETICS; POWDERS AB A variety of colloidal and polymeric sols, some doped with transition-metal oxides, were investigated as potential precursors to calcium hexaluminate (CaAl12O19) in an attempt to enhance reactivity and lower the formation and texturing temperatures of phase-pyre powders and films. One undoped polymeric sol was found to yield CaAl12O19, free of any intermediate phases, at temperatures as low as 1300 degrees C in 1 h, Doping the same mixed-metal, citrate-based precursor with a variety of transition-metal cations was found either to enhance the gamma- --> alpha-Al2O3 phase transformation or to enhance the formation of CaAl12O19. Incorporation of MnO, Fe2O3, CoO, NiO, CuO, ZnO, or SiO2 into the citrate precursor resulted in significant hexaluminate formation within 1 h at 1100 degrees C, compared with negligible formation using the undoped precursor. Fe2O3-doped precursors gave the highest hexaluminate yields at 1100 degrees C, Phase-pure hibonite was obtained at temperatures as low as 1000 degrees C with 25 at,% Fe substituting for Al in the hexaluminate structure. Textured CaAl11.5Fe0.5O19 films with (0001) planes parallel to the substrate surface were obtained on YAG substrates in 1 h at 1200 degrees C. In comparison, undoped citrate-derived films first textured at 1300 degrees C, Enhanced CaAl12O19 formation was attributed to rapid reaction of the constituents, due to the uniform dispersion of cations on an atomistic scale throughout the citrate-based precursor, prior to completion of the gamma- --> alpha-Al2O3 phase transformation, Solid-solution dopants were believed to further enhance reactivity and grain growth by increasing diffusive mass transport. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Cinibulk, MK (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 75 TC 28 Z9 28 U1 4 U2 11 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1998 VL 81 IS 12 BP 3157 EP 3168 DI 10.1111/j.1151-2916.1998.tb02751.x PG 12 WC Materials Science, Ceramics SC Materials Science GA 149CR UT WOS:000077588000013 ER PT J AU Burkett, DA Carlson, DA Kline, DL AF Burkett, DA Carlson, DA Kline, DL TI Analysis of composition of sugar meals of wild mosquitoes by gas chromatography SO JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION LA English DT Article DE mosquito; nectar feeding; sugar feeding; honeydew; gas chromatography; melezitose; quantitation ID PERFORMANCE LIQUID-CHROMATOGRAPHY; AEDES-AEGYPTI; NATURAL-POPULATIONS; HONEYDEW SUGARS; BEMISIA-TABACI; CULEX-TARSALIS; NECTAR SOURCES; DIPTERA; CULICIDAE; PATTERNS AB Gas chromatography (GC) was successfully used for the first time to determine the components of natural sugar meals in individual mosquitoes and to determine whether carbohydrases are present in the crops of these insects. Crops of wild mosquitoes collected from a 2-ha cypress swamp north of Gainesville, FL, contained fructose, glucose, sucrose, maltose, turanose, melibiose,. erlose, melezitose, raffinose, and a few unidentified carbohydrates. Time course studies with male and female Aedes albopictus showed rapid hydrolysis (>90%) of sucrose occurring within 2 h of ingestion, whereas melezitose remained relatively unchanged even 8 h after ingestion. The crop extraction/GC analysis technique is an improvement over the cold anthrone test traditionally used for sugar analysis. This procedure is a rapid one-step process used to determine natural sugar sources, hydrolysis, occurrence, and preferences for individual wild sugar-feeding Diptera. C1 Univ Florida, Inst Food & Agr Sci, Dept Entomol & Nematol, Gainesville, FL 32611 USA. USAF, Biomed Serv Corp, Med Entomol Branch, Okinawa, Japan. USDA ARS, Ctr Med Agr & Vet Entomol, Gainesville, FL 33608 USA. RP Burkett, DA (reprint author), Univ Florida, Inst Food & Agr Sci, Dept Entomol & Nematol, POB 110620, Gainesville, FL 32611 USA. NR 55 TC 6 Z9 6 U1 1 U2 8 PU AMER MOSQUITO CONTROL ASSN INC PI LAKE CHARLES PA 2200 E PRIEN LAKE RD, LAKE CHARLES, LA 70601 USA SN 8756-971X J9 J AM MOSQUITO CONTR JI J. Am. Mosq. Control Assoc. PD DEC PY 1998 VL 14 IS 4 BP 373 EP 379 PG 7 WC Entomology SC Entomology GA 174BE UT WOS:000079013600004 PM 10084129 ER PT J AU Harney, MME AF Harney, MME TI The quiet revolution: Downsizing, outsourcing, and best value SO MILITARY LAW REVIEW LA English DT Article AB In the process of governing, the government should not compete with its citizens. The competitive enterprise system, characterized by individual freedom and initiative, is the primary source of national economic growth. In recognition of this principle, it has been and continues to be the general policy of the government to rely on commercial sources to supply the products and services the government needs.(2) We are today engaged in a quiet revolution that extends across the range of our activities.(3). C1 USAF, Judge Advocate Gen Dept, Washington, DC 20330 USA. RP Harney, MME (reprint author), USA, Judge Advocate Gen Sch, Contract & Fiscal Law Dept, Charlottesville, VA 22901 USA. NR 52 TC 1 Z9 1 U1 0 U2 1 PU JUDGE ADVOCATE GENERALS SCHOOL PI CHARLOTTESVILLE PA US ARMY, CHARLOTTESVILLE, VA 22903-1781 USA SN 0026-4040 J9 MIL LAW REV JI Milit. Law Rev. PD DEC PY 1998 VL 158 BP 48 EP 108 PG 61 WC Law SC Government & Law GA 151KQ UT WOS:000077719600002 ER PT J AU Stanczak, DE AF Stanczak, DE TI Methodological considerations in the neuropsychological study of central nervous system underarousal with a specific emphasis on coma SO NEUROPSYCHOLOGY REVIEW LA English DT Article DE central nervous system; underarousal; stupor; coma; pathology; methodology; behavior; medicine; neurobehavior ID REACTION-LEVEL-SCALE; GLASGOW; RLS85; CONSCIOUSNESS; GUIDELINES; DISORDERS; ATTENTION; AROUSAL; STATES; TOOL AB Several obstacles exist that impede the scientific study of pathological underarousal (stupor and coma). For instance, there is a lack of a clear, rational, standardized taxonomy with which to describe the phenomenon. Moreover, there is considerable confusion of the construct of arousal with other neurobehavioral constructs. The field also suffers from a general lack of acceptably reliable and valid instruments, especially measures of long-term outcome. Additionally, current treatments for chronic pathological underarousal are frequently presumptive and applied haphazardly, and thus do little to elucidate the process of recovery. It is suggested that biomedical and neuropsychological approaches to the study and treatment of pathological underarousal are complementary and that it is useful to view pathological underarousal as a behavioral, as well as a medical, phenomenon. C1 Wilford Hall USAF Med Ctr, Psychol Res Serv, Lackland AFB, TX 78236 USA. RP Stanczak, DE (reprint author), MMCNB, 59th Med Wing,2200 Bergquist Dr,Suite 1, Lackland AFB, TX USA. NR 55 TC 1 Z9 2 U1 0 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA CONSULTANTS BUREAU, 233 SPRING ST, NEW YORK, NY 10013 USA SN 1040-7308 J9 NEUROPSYCHOL REV JI Neuropsychol. Rev. PD DEC PY 1998 VL 8 IS 4 BP 191 EP 201 DI 10.1023/A:1021670203013 PG 11 WC Psychology, Clinical; Neurosciences SC Psychology; Neurosciences & Neurology GA 162MC UT WOS:000078349800002 PM 9951710 ER PT J AU Cowan, WD Lee, MK Welsh, BM Bright, VM Roggemann, MC AF Cowan, WD Lee, MK Welsh, BM Bright, VM Roggemann, MC TI Optical phase modulation using a refractive lenslet array and microelectromechanical deformable mirror SO OPTICAL ENGINEERING LA English DT Article DE microoptoelectromechanical systems; deformable mirrors; micro-mirrors; aberration control; beam steering ID MICROMIRROR ARRAYS; ADAPTIVE OPTICS; PERFORMANCE; ACTUATORS AB Microelectromechanical deformable mirrors (MEM-DMs) are attractive for optical phase modulation applications primarily because of their inherently low cost and low drive voltages. Two problems limiting widespread use of segmented piston MEM-DMs are low optical efficiency (fill factor) and undesired amplitude modulation resulting from interference with the static background structure. Using a lenslet array to focus the incident light onto only the reflective surface of the MEM-DM greatly improves the effective fill factor with a corresponding decrease in interference effects. A refractive lenslet array is used with a very low fill factor MEM-DM (similar to 7%) to comprise a correcting element that behaves like a 70 to 80% fill factor device. The MEM-DM has 128 active piston micromirror elements. Experiments employing the hybrid correcting element demonstrate single beam steering, dual beam steering, and optical aberration correction. A comprehensive model of the lenslet/MEM-DM geometry is developed. Measured data shows goad agreement with model predictions. A thermal circuit model is developed to estimate optical power handling capability of the MEM-DM. A conservative estimate of maximum optical power for this particular MEM-DM is 4 W/element when operated in a helium ambient, suggesting that relatively high power laser control applications are feasible, (C) 1998 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(98)01812-1]. C1 USAF, Res Lab, MLP, AFRL, Wright Patterson AFB, OH 45433 USA. Univ Colorado, Dept Mech Engn, Boulder, CO 80309 USA. Michigan Technol Univ, Dept Elect Engn, Houghton, MI 49931 USA. RP Cowan, WD (reprint author), USAF, Res Lab, MLP, AFRL, Bldg 651,Room 252,3005 P St, Wright Patterson AFB, OH 45433 USA. EM cowanwd@ml.wpafb.af.mil NR 26 TC 15 Z9 15 U1 0 U2 2 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 DEC PY 1998 VL 37 IS 12 BP 3237 EP 3247 DI 10.1117/1.601998 PG 11 WC Optics SC Optics GA 147VN UT WOS:000077518300020 ER PT J AU Swiatkiewicz, J Prasad, PN Reinhardt, BA AF Swiatkiewicz, J Prasad, PN Reinhardt, BA TI Probing two-photon excitation dynamics using ultrafast laser pulses SO OPTICS COMMUNICATIONS LA English DT Article DE two-photon excitation dynamics; excited-state absorption ID 2-PHOTON AB We probe the two-photon excitation dynamics of two new dyes, N, N-diphenyl-7-[2-(4-piridinyl) ethenyl]-9,9-di-n-decylfluoren-2-amine (AF50) and (7-(7-benzothiazol-2-yl-9,9-diethylfluoren-2-yl)-9,9-diethylfluoren-2-yl) diphenylamine (AF250) using femtosecond excitation pulses by Z-scan and time-resolved pump-probe absorption measurements. Irradiance dependence of the induced absorption cross section is linked to linear absorption of the two-photon excited state. The excited state linear absorption cross-section are 1.0 X 10(-17) cm(2) for AF250 and 2.7 x 10(-17) cm(2) for AF250. Relaxation of the two-photon excited state follows a complicated path with three distinct relaxation times. The longest ones, 1.6 ns for the AF50 and 1.9 ns for the AF250, are associated with the respective lowest singlet life-times: 2.23 ns and 2.15 ns. (C) 1998 Elsevier Science B.V. All rights reserved. C1 SUNY Buffalo, Dept Chem, Photon Res Lab, Buffalo, NY 14260 USA. SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. USAF, Polymer Branch, WL MLBP Mat Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Prasad, PN (reprint author), SUNY Buffalo, Dept Chem, Photon Res Lab, Buffalo, NY 14260 USA. NR 10 TC 112 Z9 112 U1 3 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD DEC 1 PY 1998 VL 157 IS 1-6 BP 135 EP 138 DI 10.1016/S0030-4018(98)00474-X PG 4 WC Optics SC Optics GA 148PU UT WOS:000077541700025 ER PT J AU Choudhury, DP Srikanth, H Sridhar, S Canfield, PC AF Choudhury, DP Srikanth, H Sridhar, S Canfield, PC TI Magnetoelectrodynamics at high frequencies in the antiferromagnetic and superconducting states of DyNi2B2C SO PHYSICAL REVIEW B LA English DT Article ID SINGLE-CRYSTAL; MICROWAVE RESPONSE; PENETRATION DEPTH; CRITICAL FIELDS; MAGNETISM; ORDER; TRANSITIONS; DEPENDENCE; ANISOTROPY; INTERPLAY AB We report our observation of the behavior of the radio frequency (rf) and microwave response of DyNi2B2C over a wide range of temperature (T) and magnetic field (H) in the antiferromagnetic (AFM) and superconducting (SC) states. At microwave frequencies of 10 GHz, the T dependence of the surface impedance Z(s) = R-s+ iX(s) was measured which yields the T dependence of the complex conductivity sigma(1) - i sigma(2) in the SC and AFM states. At radio frequencies (4 MHz), the H and T dependence of the penetration depth lambda(T,H) were measured. The establishment of antiferromagnetic order at T-N = 10.3 K results in a marked decrease in the scattering of charge carriers, leading to sharp decreases in R-s and X-s. However, R-s and X-s differ from each other in the AFM state. We show that the results are consistent with relaxation processes whence the scattering rate becomes comparable to the microwave frequency. The rf measurements yield a rich dependence of the scattering on the magnetic field near and below T-N. Anomalous decrease of scattering at moderate applied fields is observed at temperatures near and above T-N, and arises due to a crossover from a negative magnetoresistance state, possibly associated with a loss of spin disorder scattering at low fields, to a positive magnetoresistance state associated with the metallic nature. The normal state magnetoresistance is positive at all temperatures for mu(0)H>2 T and at all fields for T> 15 K. Several characteristic field scales associated with metamagnetic: transitions [H-M1(T),H-M2(T)], the onset of spin disorder H-D(T) and The upper critical field H-c2(T) are observed in the rf measurements. [S0163-1829 (98)04342-2]. C1 Northeastern Univ, Dept Phys, Boston, MA 02115 USA. USAF, Res Lab, Bedford, MA 01730 USA. Iowa State Univ Sci & Technol, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. RP Choudhury, DP (reprint author), Northeastern Univ, Dept Phys, Boston, MA 02115 USA. RI Sridhar, Srinivas/A-3688-2012; Canfield, Paul/H-2698-2014 NR 50 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 1 PY 1998 VL 58 IS 21 BP 14490 EP 14497 DI 10.1103/PhysRevB.58.14490 PG 8 WC Physics, Condensed Matter SC Physics GA 144RC UT WOS:000077328000069 ER PT J AU Weyburne, DW AF Weyburne, DW TI Variable property similarity transform: Application to axisymmetric fluid flow against a heated disk SO PHYSICAL REVIEW E LA English DT Article ID VAPOR-DEPOSITION REACTOR; DESIGN AB A variable property stream function is combined with a similarity variable transform to create a new class of variable property similarity transforms. The exact fluid flow solutions that are obtained with the new similarity transforms will be identical to the normally formulated similarity solutions. The utility of the new transforms will be for developing approximate analytical solutions. This is because the reformulation splits the normal transform into a slowly varying temperature functional and the rapidly temperature varying mass density. By assuming the functional is temperature invariant, approximate analytical solutions can be obtained by combining this approximate functional with a mass density profile approximation. The new approximate velocity solutions show the spatial variation behavior one would expect for a system with a temperature gradient present, in contrast to existing approximate methods that are based on average-property approximations. The new approximate analytical solutions, therefore, provide valuable insights into the expected thermal behavior and dependencies of the fluid system that cannot be obtained with exact numerical solutions or existing approximate methods. In addition, the approximate analytical solutions provide a straightforward path to the development of approximate thermal flow stability criteria. To demonstrate the utility of the new transform, the present study applies the new variable property similarity transform to the case of axisymmetric fluid flow against a heated disk. [S1063-651X(98)12112-8]. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Weyburne, DW (reprint author), USAF, Res Lab, 80 Scott Dr, Hanscom AFB, MA 01731 USA. NR 10 TC 1 Z9 1 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD DEC PY 1998 VL 58 IS 6 BP 7402 EP 7409 DI 10.1103/PhysRevE.58.7402 PN A PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 148PV UT WOS:000077541800073 ER PT J AU Freeman, TM AF Freeman, TM TI Anaphylaxis - Diagnosis and treatment SO PRIMARY CARE LA English DT Article ID EXERCISE-INDUCED ANAPHYLAXIS; SYSTEMIC-ANAPHYLAXIS; HYPERSENSITIVITY AB Anaphylaxis is a clinical syndrome and is caused by many different agents. Acute therapy is epinephrine. Chronic therapy depends on the agent causing the anaphylaxis, but usually consists of avoidance of the agent only. Individuals who suffer from this problem should be issued epinephrine and wear or carry medical alert bracelets. C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. RP Freeman, TM (reprint author), Wilford Hall USAF Med Ctr, 59th Med Wing,PSMA,2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 19 TC 8 Z9 9 U1 0 U2 1 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0095-4543 J9 PRIMARY CARE JI Primary Care PD DEC PY 1998 VL 25 IS 4 BP 809 EP + DI 10.1016/S0095-4543(05)70089-0 PG 10 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 146RN UT WOS:000077444400007 PM 9735120 ER PT J AU Graetz, KA Boyle, ES Kimble, CE Thompson, P Garloch, JL AF Graetz, KA Boyle, ES Kimble, CE Thompson, P Garloch, JL TI Information sharing face-to-face teleconferencing, and electronic chat groups SO SMALL GROUP RESEARCH LA English DT Article ID COMPUTER-MEDIATED COMMUNICATION; DECISION-MAKING GROUPS; UNSHARED INFORMATION; PERFORMANCE; TASK; RICHNESS; JUDGMENT AB Laboratory groups attempted to reach consensus on a simulated business problem. Members of 4-person groups received information on whether three proposed systems met each of 10 desired criteria. Cast as a hidden profile problem the information was distributed unevenly within the group. Groups communicated using one of three formats:face-to-face, teleconference, or electronic chat. As predicted, cognitive workload was significantly higher and fewer correct decisions were obtained in the electronic chat condition versus the other two formats. The electronic chat medium limited participants' ability to coordinate and verify information. Electronic char should be combined with collaboration technology or groupware that facilitates information storage, organization, and processing. C1 Univ Dayton, Dayton, OH 45469 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Graetz, KA (reprint author), Univ Dayton, Dayton, OH 45469 USA. NR 45 TC 60 Z9 61 U1 1 U2 10 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1046-4964 J9 SMALL GR RES JI Small Group Res. PD DEC PY 1998 VL 29 IS 6 BP 714 EP 743 DI 10.1177/1046496498296003 PG 30 WC Psychology, Applied; Management; Psychology, Social SC Psychology; Business & Economics GA 142TR UT WOS:000077216900003 ER PT J AU de Blonk, BJ Lagoudas, DC AF de Blonk, BJ Lagoudas, DC TI Actuation of elastomeric rods with embedded two-way shape memory alloy actuators SO SMART MATERIALS & STRUCTURES LA English DT Article ID ACTIVE FLEXIBLE RODS; CONSTITUTIVE MODEL; BEHAVIOR; DEFORMATIONS; COMPOSITES AB The modelling and experimental results of deformations of elastomeric rods with embedded two-way shape memory effect actuators is presented in this work. A procedure is established to train Nitinol shape memory alloy (SMA) wires to exhibit the two-way shape memory effect, a hysteretic behaviour involving a thermally induced, zero-stress, kinematically reversible transformation strain. A flexible silicone elastomer rod is embedded with two of these SMA actuators at an offset from the neutral axis. Resistive heating of an SMA actuator causes SMA transformation strain recovery and hence induces bending strain in the rod; cooling of the SMA actuator back to room temperature relaxes the rod to its initial position. The inclusion of two opposing actuators provides the ability to actuate the rod in two opposing directions. The deflection of a flexible rod with embedded two-way SMA actuators is modelled with both a general theory of flexible rods and an approximate formula. The experiments and modelling demonstrate the feasibility of using SMA actuators for large shape change in active flexible structures. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. Texas A&M Univ, Dept Aerosp Engn, College Stn, TX 77843 USA. OI Lagoudas, Dimitris/0000-0002-0194-5933 NR 40 TC 36 Z9 36 U1 1 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0964-1726 J9 SMART MATER STRUCT JI Smart Mater. Struct. PD DEC PY 1998 VL 7 IS 6 BP 771 EP 783 PG 13 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA 158FQ UT WOS:000078105700005 ER PT J AU Mall, S Coleman, JM AF Mall, S Coleman, JM TI Monotonic and fatigue loading behavior of quasi-isotropic graphite/epoxy laminate embedded with piezoelectric sensor SO SMART MATERIALS & STRUCTURES LA English DT Article ID PERFORMANCE; COMPOSITE AB This study investigated the effects of embedding piezoelectric lead zirconate-titanate (PZT) sensors on the tensile strength and fatigue behavior of a quasi-isotropic graphite/epoxy laminate as well as the embedded sensor's voltage degradation under these loading conditions. For this, AS4/3501-6 laminates were fabricated with a [0/+/-45/90](S) lay-up where PZT was inserted into a cut-out area in the two middle 90 degrees plies. Monotonic tensile tests showed that both the average ultimate strength and Young's modulus of the tested laminate with or without PZT were within 4% of each other. The fatigue lives with and without PZT were very close to each other as well. Overall, the sequence of damage in this study agreed with previous investigations of the damage mechanisms for [0/+/-45/90](S) quasi-isotropic laminates. The ranges of modulus reduction in both cases, with and without PZT, were within 5 to 15% of each other during fatigue loading. Delamination growths in both cases during most of the fatigue life were also very comparable to each other. Further, this study showed that the embedded PZT would maintain a steady voltage output indefinitely when mechanically cycled within its operational strain limit. It thus appears that the embedment of PZTs in a cut-out area of 90 degrees plies of quasi-isotropic graphite/epoxy laminates would not affect their monotonic tensile and fatigue behavior. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 11 TC 54 Z9 55 U1 0 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0964-1726 J9 SMART MATER STRUCT JI Smart Mater. Struct. PD DEC PY 1998 VL 7 IS 6 BP 822 EP 832 DI 10.1088/0964-1726/7/6/010 PG 11 WC Instruments & Instrumentation; Materials Science, Multidisciplinary SC Instruments & Instrumentation; Materials Science GA 158FQ UT WOS:000078105700010 ER PT J AU Wimmer, AP Bouffard, JP Storms, PR Pilcher, JA Liang, CY DeGuide, JJ AF Wimmer, AP Bouffard, JP Storms, PR Pilcher, JA Liang, CY DeGuide, JJ TI Primary colon cancer without gross mucosal tumor: Unusual presentation of a common malignancy SO SOUTHERN MEDICAL JOURNAL LA English DT Article ID COLORECTAL-CANCER; ADENOMAS; ADENOCARCINOMAS; POLYPECTOMY; PREVENTION; ANTIGEN AB Colon cancer typically arises in the colonic lumen, allowing for endoscopic detection of cancerous and premalignant lesions. In the case presented, a 73-year-old man with iron deficiency anemia had two colonoscopies showing only diverticula and internal hemorrhoids. Three years later, when the patient complained of dull, intermittent lower abdominal pain, a third colonoscopy identified diverticula, three adenomatous polyps, and no other abnormality. Computed tomography (CT) of the abdomen revealed a 5 cm x 6 cm pericolic fluid collection, which was later found to communicate with the sigmoid colon. The surgical specimen from a partial colectomy contained a distal sigmoid perforation with a 2.5 cm moderately differentiated adenocarcinoma in the underlying submucosal tissue, There was no gross intraluminal tumor. Histopathology, including immunohistochemistry, was consistent with colonic adenocarcinoma. Primary colon cancer grossly sparing the mucosa is an unusual presentation for this common malignancy. C1 Wilford Hall USAF Med Ctr, Dept Med, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Pathol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Surg, Lackland AFB, TX 78236 USA. RP Wimmer, AP (reprint author), Wilford Hall USAF Med Ctr, Dept Med, 2200 Bergquist Dr,59th MWMM-R, Lackland AFB, TX 78236 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU SOUTHERN MEDICAL ASSN PI BIRMINGHAM PA 35 LAKESHORE DR PO BOX 190088, BIRMINGHAM, AL 35219 USA SN 0038-4348 J9 SOUTHERN MED J JI South.Med.J. PD DEC PY 1998 VL 91 IS 12 BP 1173 EP 1176 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 146DR UT WOS:000077413200017 PM 9853735 ER PT J AU Hedrick, A AF Hedrick, A TI Dumbbell training for football at the US Air Force Academy SO STRENGTH AND CONDITIONING LA English DT Article C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Hedrick, A (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 7 TC 4 Z9 4 U1 0 U2 0 PU HUMAN KINETICS PUBL INC PI CHAMPAIGN PA 1607 N MARKET ST, CHAMPAIGN, IL 61820-2200 USA SN 1073-6840 J9 STRENGTH COND JI Strength Cond. PD DEC PY 1998 VL 20 IS 6 BP 34 EP 39 DI 10.1519/1073-6840(1998)020<0034:DTFFAT>2.3.CO;2 PG 6 WC Sport Sciences SC Sport Sciences GA 148MA UT WOS:000077508000007 ER PT J AU Triantafillou, SA Schwendeman, DW Cole, JD AF Triantafillou, SA Schwendeman, DW Cole, JD TI Optimization of conical wings in hypersonic flow SO THEORETICAL AND COMPUTATIONAL FLUID DYNAMICS LA English DT Article AB A method of calculation is presented to determine conical wing shapes that minimize the coefficient of (wave) drag, C-D, for a fixed coefficient of lift, C-L, in steady, hypersonic flow. An optimization problem is considered for the compressive flow underneath wings at a small angle of attack delta and at a high free-stream Mach number M-infinity so that hypersonic small-disturbance (HSD) theory applies. A figure of merit, F = C-D/C-L(3/2), is computed for each wing using a finite volume discretization of the HSD equations. A set of design variables that determine the shape of the wing is defined and adjusted iteratively to find a shape that minimizes F for a given value of the hypersonic similarity parameter, H = (M(infinity)delta)(-2), and planform area. Wings with both attached and detached bow shocks are considered. Optimal wings are found for flat delta wings and for a family of caret wings. In the flat-wing case, the optima have detached how shocks while in the caret-wing case, the optimum has an attached bow shock. An improved drag-to-lift performance is found using the optimization procedure for curved wing shapes. Several optimal designs are found, all with attached bow shocks. Numerical experiments are performed and suggest that these optima are unique. C1 Rensselaer Polytech Inst, Dept Math Sci, Troy, NY 12180 USA. RP Triantafillou, SA (reprint author), USAF, VSBE, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0935-4964 J9 THEOR COMP FLUID DYN JI Theor. Comput. Fluid Dyn. PD DEC PY 1998 VL 12 IS 4 BP 219 EP 232 DI 10.1007/s001620050107 PG 14 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 154BP UT WOS:000077868400002 ER PT J AU Nixon, B Murphy, RJ AF Nixon, B Murphy, RJ TI Untitled - Response SO WASTE MANAGEMENT & RESEARCH LA English DT Letter C1 USAF, Inst Technol, Grad Sch Engn, Wright Patterson AFB, OH 45433 USA. Univ S Florida, Coll Engn, Tampa, FL 33620 USA. RP Nixon, B (reprint author), USAF, Inst Technol, Grad Sch Engn, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0734-242X J9 WASTE MANAGE RES JI Waste Manage. Res. PD DEC PY 1998 VL 16 IS 6 BP 595 EP 596 DI 10.1177/0734242X9801600611 PG 2 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 144FB UT WOS:000077302400011 ER PT J AU Eckel, FA Walters, MK AF Eckel, FA Walters, MK TI Calibrated probabilistic quantitative precipitation forecasts based on the MRF ensemble SO WEATHER AND FORECASTING LA English DT Article ID PREDICTION AB Probabilistic quantitative precipitation forecasts (PQPFs) based on the National Centers for Environmental Prediction Medium-Range Forecast (MRF) ensemble currently perform below their full potential quality (i.e., accuracy and reliability). This unfulfilled potential is due to the MRF ensemble being adversely affected by systematic errors that arise from an imperfect forecast model and less than optimum ensemble initial perturbations. This research sought to construct a calibration to account for these systematic errors and thus produce higher quality PQPFs. The main tool of the calibration was the verification rank histogram, which can be used to interpret and adjust an ensemble forecast. Using a large training dataset, many histograms were created, each characterized by a different forecast lead time and level of ensemble variability. These results were processed into probability surfaces, providing detailed information on performance of the ensemble as part of the calibration scheme. Improvement of the calibrated PQPF over the current uncalibrated PQPF was examined using a separate, large forecasting dataset, with climatological PQPF as the baseline. While the calibration technique noticeably improved the quality of PQPF and extended predictability by about 1 day, its usefulness was bounded by the intrinsic predictability limits of cumulative precipitation. Predictability was found to be dependent upon the precipitation category. For significant levels of precipitation (high thresholds), the calibration designed in this research was found to be useful only for short-range PQPFs. For low precipitation thresholds, the calibrated PQPF did prove to be of value in the medium range. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Eckel, FA (reprint author), 8373 Andrus Dr, Colorado Springs, CO 80920 USA. NR 15 TC 64 Z9 66 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0882-8156 J9 WEATHER FORECAST JI Weather Forecast. PD DEC PY 1998 VL 13 IS 4 BP 1132 EP 1147 DI 10.1175/1520-0434(1998)013<1132:CPQPFB>2.0.CO;2 PG 16 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 150KC UT WOS:000077663200015 ER PT J AU Mann, RW AF Mann, RW TI Use of bone trabeculae to establish positive identification SO FORENSIC SCIENCE INTERNATIONAL LA English DT Article DE physical anthropology; positive identification; X-rays; musculoskeletal system ID REMAINS AB Radiographic examination of 42 adult distal left femora and 38 proximal left tibiae revealed that no two bones were identical in the pattern and appearance of the trabeculae. In each case, a minimum of four distinct osseous features was easily visible on radiograph. The results indicate that radiolucencies and radiodensities in the distal femur and proximal tibia are valid individualizing features for establishing a positive personal identification in human remains. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 USA, Cent Identificat Lab, Hickam AFB, HI 96853 USA. RP Mann, RW (reprint author), USA, Cent Identificat Lab, 310 Worchester Ave, Hickam AFB, HI 96853 USA. NR 19 TC 18 Z9 20 U1 0 U2 3 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0379-0738 J9 FORENSIC SCI INT JI Forensic Sci.Int. PD NOV 30 PY 1998 VL 98 IS 1-2 BP 91 EP 99 DI 10.1016/S0379-0738(98)00138-8 PG 9 WC Medicine, Legal SC Legal Medicine GA 155DX UT WOS:000077931900009 PM 10036762 ER PT J AU Dean, D Husband, M Trimmer, M AF Dean, D Husband, M Trimmer, M TI Time-temperature-dependent behavior of a substituted poly(paraphenylene): Tensile, creep, and dynamic mechanical properties in the glassy state SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE poly(paraphenylenes); viscoelastic; creep; physical aging ID SOLUBLE POLY(PARA-PHENYLENE)S; SIDE-CHAINS AB The linear viscoelastic behavior of a poly(paraphenylene) with a benzoyl substituent has been examined using tensile, dynamic mechanical, and creep experiments. This amorphous polymer was shown to have a tensile modulus of 1-1.5 Msi, nearly twice that of most common engineering thermoplastics. The relaxation behavior, which is similar to that of common thermoplastics, can be described by the WLF equation. Outstanding creep resistance was observed at low temperatures, with rubbery-like behavior being exhibited as the temperature approached T-g. Physical aging was shown to interact with long-term creep, rendering time-temperature superposition invalid for predicting the long-term properties. The effect of physical aging on the creep behavior was characterized by the shift rate mu. (C) 1998 John Wiley & Sons, Inc. C1 USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Maxdem Inc, San Dimas, CA 91773 USA. RP Dean, D (reprint author), BF Goodrich Co, Adv Technol Grp, 9921 Brecksville Rd, Brecksville, OH 44141 USA. NR 32 TC 12 Z9 12 U1 0 U2 7 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD NOV 30 PY 1998 VL 36 IS 16 BP 2971 EP 2979 DI 10.1002/(SICI)1099-0488(19981130)36:16<2971::AID-POLB12>3.3.CO;2-I PG 9 WC Polymer Science SC Polymer Science GA 136BC UT WOS:000076837000012 ER PT J AU Jata, KV Vasudevan, AK Bales, TT AF Jata, KV Vasudevan, AK Bales, TT TI International Conference on Crystallographic Texture and Mechanical Anisotropy - 1-5 September 1997 - Hyannis, Masschusetts - Preface SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Editorial Material C1 USAF, Res Lab, Mat Directorate, Washington, DC 20330 USA. Off Naval Res, Arlington, VA 22217 USA. NASA, Langley Res Ctr, Hampton, VA 23665 USA. RP Jata, KV (reprint author), USAF, Res Lab, Mat Directorate, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 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 NOV 30 PY 1998 VL 257 IS 1 BP XI EP XI PG 1 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 147LZ UT WOS:000077570400002 ER PT J AU Jata, KV Panchanadeeswaran, S Vasudevan, AK AF Jata, KV Panchanadeeswaran, S Vasudevan, AK TI Evolution of texture, microstructure and mechanical property anisotropy in an Al-Li-Cu alloy SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Crystallographic Texture and Mechanical Anisotropy CY SEP 01-05, 1997 CL CAPE COD, MASSACHUSETTS SP USAF, Res Lab Adv Metall, NASA, Off Naval Res, Engn Fdn DE Al-Li-Cu alloy; texture; microstructure; anisotropy ID ROLLING TEXTURES; RECRYSTALLIZATION; DEFORMATION AB The evolution of hot deformation texture, microstructure and yield strength anisotropy in an Al-Li-Cu alloy AF/C489 was studied in the as-extruded, solution heat treated and peak-aged condition. Cast AF/C489 alloy with a random texture was extruded at six temperatures ranging from 260 to 538 degrees C and immediately quenched to capture texture and microstructure at the extrusion temperature. In the as-extruded condition, significant amounts of the major rolling texture components, namely, Br {112}[110], S {123}[634] and Cu {112}[111] were observed at all extrusion temperatures. However, at extrusion temperatures above 480 degrees C there was a sharp rise in the intensity of Br component. When the extruded alloy was solution treated the Br intensity remained stable for the two highest extrusion temperatures. However, solution heat treatment (SHT) following extrusion at lower temperatures resulted in the loss of all the rolling texture components including Br. Furthermore, the solution heat treatment following extrusion at temperatures below 330 degrees C showed presence of significant amount of ND rotated cube ({100}[130]). It is suggested that formation of Br texture may be due to the development of shear bands. Increase in dynamic recovery at high extrusion temperature enhances the shear banding tendency and consequently increased presence of Br. This is consistent with negligible recrystallization during solution treatment following elevated temperature extrusion as observed by optical microscopy. Significant recrystallization during SHT following low temperature extrusion results in the presence of rotated cube components. This is consistent with the presence of more particles at low temperature as observed by transmission electron microscopy. The yield stress anisotropy in the SHT material is attributed to crystallographic texture in the SHT material whereas in the extruded case the anisotropy is due to the combined effect of particles and texture. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. Alumax Tech Ctr, Golden, CO 80403 USA. Off Naval Res, Arlington, VA 22217 USA. RP Jata, KV (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Mat Dev & Proc Branch, Wright Patterson AFB, OH 45433 USA. EM jatakv@ml.wpafb.af.mil NR 18 TC 22 Z9 27 U1 3 U2 10 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 NOV 30 PY 1998 VL 257 IS 1 BP 37 EP 46 DI 10.1016/S0921-5093(98)00822-3 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 147LZ UT WOS:000077570400006 ER PT J AU Rollett, AD Smith, PR James, MR AF Rollett, AD Smith, PR James, MR TI Texture and anisotropy of Ti-22Al-23Nb foil SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Crystallographic Texture and Mechanical Anisotropy CY SEP 01-05, 1997 CL CAPE COD, MASSACHUSETTS SP USAF, Res Lab Adv Metall, NASA, Off Naval Res, Engn Fdn DE texture; anisotropy; Ti-22Al-23Nb foil ID DEFORMATION; ALLOY; BEHAVIOR; PHASE AB The texture and anisotropy of as-rolled and rolled and annealed Ti-22Al-23Nb foil have been investigated. The texture of the b.c.c. phase was analyzed and used to calculate the anisotropy of the foil. The predicted variation in yield stress is in good agreement with the experimental results. The texture of the b.c.c, phase is similar to textures observed in conventional b.c.c. alloys. The texture of the orthorhombic and hexagonal phases has also been analyzed. Although limited data exist for the single crystal properties of the alpha phase, prediction of the anisotropy of the orthorhombic phase is hindered by the absence of such data. The results to date indicate that the texture of the cubic phase predicts the anisotropy of the intermetallic foil reasonably well. Theoretical analysis of the single crystal yield surface of the orthorhombic phase shows that a deformation mode map can be constructed for this material. Comparison of simulated with experimental textures suggest limits on the variation of critical resolved sheer stress among the four different slip systems. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. USAF, Mat Directorate, Wright Lab, Wright Patterson AFB, OH 45433 USA. Rockwell Int Corp, Ctr Sci, Thousand Oaks, CA 91358 USA. RP Rollett, AD (reprint author), Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. EM rol-lett@andrew.cmu.edu RI Rollett, Anthony/A-4096-2012 OI Rollett, Anthony/0000-0003-4445-2191 NR 21 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD NOV 30 PY 1998 VL 257 IS 1 BP 77 EP 86 DI 10.1016/S0921-5093(98)00825-9 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 147LZ UT WOS:000077570400009 ER PT J AU Ari-Gur, P Semiatin, SL AF Ari-Gur, P Semiatin, SL TI Evolution of microstructure, macrotexture and microtexture during hot rolling of Ti-6Al-4V SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Conference on Crystallographic Texture and Mechanical Anisotropy CY SEP 01-05, 1997 CL CAPE COD, MASSACHUSETTS SP USAF, Res Lab Adv Metall, NASA, Off Naval Res, Engn Fdn DE Ti-6Al-4V; annealing; globularization ID TI-6AL-2SN-4ZR-2MO-0.1SI; DEFORMATION; MICROSCOPY AB The evolution of microstructure. macrotexture and microtexture during subtransus hot working of Ti-6Al-4V with two different types of transformed beta starting microstructures (lamellar colony, acicular/martensitic alpha) was investigated. Globularization of the transformed microstructures required heavy rolling reductions or moderate reductions coupled with near transus post-rolling heat treatment. Despite the sluggish dynamic globularization kinetics, noticeable macrotexture changes were noted after low reductions. an effect ascribed to the rotations associated with kinking and bending of the lamellar/acicular plates. Noticeable microtextures, noted in samples with an initial lamellar colony microstructure, persisted through hot rolling suggesting that dynamic globularization does not involve recrystallization. In contrast, hot rolled material with a starting acicular alpha microstructure exhibited weak microtextures and strong macrotextures. The absence of microtexture in these latter cases was explained on the basis of multiple transformation variants within each colony/prior beta grain following the beta-annealing-and-water-quenching process used to obtain the microstructure. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Western Michigan Univ, Mat Sci & Engn Program, Kalamazoo, MI 49008 USA. USAF, Mat & Mfg Directorate, Res Lab, MLLM, Wright Patterson AFB, OH 45433 USA. RP Ari-Gur, P (reprint author), Western Michigan Univ, Mat Sci & Engn Program, Kalamazoo, MI 49008 USA. EM arig-urp@wmich.edu RI SEMIATIN, SHELDON/E-7264-2017 NR 21 TC 35 Z9 36 U1 5 U2 23 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 NOV 30 PY 1998 VL 257 IS 1 BP 118 EP 127 DI 10.1016/S0921-5093(98)00829-6 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 147LZ UT WOS:000077570400013 ER PT J AU Boyes, CPE AF Boyes, CPE TI USAF continued wargames SO AVIATION WEEK & SPACE TECHNOLOGY LA English DT Letter C1 USAF, Rancho Murieta, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL INC PI NEW YORK PA 1221 AVENUE OF THE AMERICAS, NEW YORK, NY 10020 USA SN 0005-2175 J9 AVIAT WEEK SPACE TEC JI Aviat. Week Space Technol. PD NOV 23 PY 1998 VL 149 IS 21 BP 6 EP 6 PG 1 WC Engineering, Aerospace SC Engineering GA 140XF UT WOS:000077114400004 ER PT J AU Arnold, ST Thomas, JM Viggiano, AA AF Arnold, ST Thomas, JM Viggiano, AA TI Reactions of H3O+(H2O)(n) and H+(H2O)(n)(CH3COCH3)(m) with CH3SCH3 SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE ion molecule; rate constants; proton hydrates; dimethylsulfide; chemical ionization mass spectrometry ID RATE CONSTANTS; TRAJECTORY CALCULATIONS; MASS-SPECTROMETRY; TEMPERATURE AB We have measured the rate constants and product branching fractions for the reactions of water clusters and mixed water/acetone clusters, H3O+(H2O)(n) and H+(H2O)(n)(CH3COCH3)(m), reacting with dimethylsulfide, CH3SCH3. The proton hydrates react rapidly. For n = 0-2, the reactions proceed at the collision rate within experimental error, while the reaction efficiency decreases slightly for n = 3 and further for n = 4 and n 5. The product distributions for the higher clusters are mainly switching one H2O for the CH3SCH3. The product distributions appear to be affected by thermal dissociation at higher temperatures. The reactions of H+(H2O)(n)(CH3COCH3)(m) with CH3SCH3 are also rapid and proceed by switching both a CH3COCH3 and a H2O out of the primary ion. The rate constant for H+(CH3COCH3)(2) is very slow, although the addition of two H2O ligands increases reaction by a factor of 13 and 21, respectively. The reactivity of H+(H2O)(CH3COCH3)(3) decreases to a value close to that of H+(CH3COCH3)(2). These results indicate that H3O+(H2O)(n) ions can be used as chemical ionization agents for CH3SCH3 detection in the atmosphere and that use of the mixed cluster ions, H+(H2O)(n) (CH3COCH3)(m), would be problematic. (C) 1998 Elsevier Science B.V. C1 USAF, Res Lab, Space Vehicles Directorate, Space Phys Models Branch,VSBP, Hanscom AFB, MA 01731 USA. RP Viggiano, AA (reprint author), USAF, Res Lab, Space Vehicles Directorate, Space Phys Models Branch,VSBP, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 19 TC 8 Z9 8 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 EI 1873-2798 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD NOV 23 PY 1998 VL 179 BP 243 EP 251 DI 10.1016/S1387-3806(98)14143-X PG 9 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 140RD UT WOS:000077101400025 ER PT J AU Simpson, JP Witteborn, FC Price, SD Cohen, M AF Simpson, JP Witteborn, FC Price, SD Cohen, M TI Midcourse Space Experiment spectra of the Orion Nebula and the implications for abundances in the interstellar medium SO ASTROPHYSICAL JOURNAL LA English DT Article DE infrared : ISM : continuum; infrared : ISM : lines and bands; ISM : individual (Orion Nebula) ID INFRARED-EMISSION BANDS; EFFECTIVE COLLISION STRENGTHS; AROMATIC HYDROCARBON CATIONS; FINE-STRUCTURE TRANSITION; PURE-ROTATIONAL EMISSION; LOW-DENSITY PLASMAS; I LINE-INTENSITIES; ATOMIC DATA; IRON PROJECT; CHEMICAL-COMPOSITION AB Spectra of the Orion Nebula were obtained with the Midcourse Space Experiment Spirit III interferometer from 370 to 2000 cm(-1) with 2 cm(-1) resolution in a 6' x 9' held of view (FOV) in 1996 November. Lines were detected of [S III] 534.4 cm(-1), [Ne III] 642.9 cm(-1), [Ne II] 780.4 cm(-1), [S IV] 951.4 cm(-1), [Ar III] 1112.2 cm(-1), [Ar II] 1431.6 cm(-1), H (7-6) 808.3 cm(-1), H (8-6) 1332.9 cm(-1), H (6-5) 1340.5 cm(-1), H-2(S1) 587.0 cm(-1), H-2(S2) 814.4 cm(-1), H-2(S3) 1034.7 cm(-1), H-2(S4) 1246.1 cm(-1), and H-2(S5) 1447.3 cm(-1). The following abundances were determined from these lines: Ne/H = 9.9 +/- 1.1 x 10(-5), S/H = 8.1 +/- 1.1 x 10(-6), and Ar/H = 2.5 +/- 0.2 x 10(-6). These abundances are all less than solar and confirm that the Sun is overabundant in heavy elements without the need for correction for the composition of interstellar dust. The low sulfur abundance compared with solar is an indication that a significant amount of the sulfur in Orion is in dust grains. The FOV-averaged molecular hydrogen column density is similar to 1.6 x 10(20) cm(-2) for an excitation temperature of similar to 670 K and an extinction correction corresponding to an optical depth of 1.5 at 9.7 mu m. The unidentified infrared emission features at 6.2, 7.7, 8.6, 11.3, and 12.7 mu m, attributable to polycyclic aromatic hydrocarbons, were also detected. A prominent, broad silicate feature centered near 18 mu m and additional weak features were detected and are discussed. C1 NASA, Ames Res Ctr, Astrophys Branch, Moffett Field, CA 94035 USA. SETI Inst, Moffett Field, CA 94035 USA. USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA. RP Simpson, JP (reprint author), NASA, Ames Res Ctr, Astrophys Branch, MS 245-6, Moffett Field, CA 94035 USA. NR 51 TC 25 Z9 25 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD NOV 20 PY 1998 VL 508 IS 1 BP 268 EP 274 DI 10.1086/306388 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152LX UT WOS:000077780000021 ER PT J AU MacLachlan, MJ Weeks, DE AF MacLachlan, MJ Weeks, DE TI A new application of the interaction picture to calculate reactive scattering matrix elements SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID DEPENDENT SCHRODINGER-EQUATION; ABSORBING BOUNDARY-CONDITIONS; INTERACTION REPRESENTATION; QUANTUM-MECHANICS; TIME; FORMULATION; DYNAMICS; PREDISSOCIATION; PROPAGATION; REFLECTION AB The interaction picture is used together with the channel-packet method in a new time-dependent approach to compute reactive scattering matrix elements. The channel-packet method employs the correlation function between two Moller states to compute scattering matrix elements. The interaction picture reduces wavepacket spreading when computing the Moller states. The details of this new approach are illustrated using a simple one-dimensional example where the size of the grid required for computing the Mailer state in the interaction picture is reduced by a factor of 2 when compared with required grid size in the Schrodinger picture. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Weeks, DE (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 37 TC 4 Z9 4 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD NOV 19 PY 1998 VL 102 IS 47 BP 9489 EP 9493 DI 10.1021/jp981991u PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 165GY UT WOS:000078514000023 ER PT J AU Cooley, WT Hengehold, RL Yeo, YK Turner, GW Loehr, JP AF Cooley, WT Hengehold, RL Yeo, YK Turner, GW Loehr, JP TI Recombination dynamics in InAsSb quantum-well diode lasers measured using photoluminescence upconversion SO APPLIED PHYSICS LETTERS LA English DT Article ID 3.5 MU-M; AUGER RECOMBINATION; UP-CONVERSION; LIFETIME; INGAASP; POWER AB We report Shockley-Read-Hall (SRH), radiative, and Auger recombination rates in midinfrared laser structures from time-resolved photoluminescence using frequency upconversion. The devices studied were actual InAsSb/InAlAsSb multiple-quantum-well (MQW) diode lasers emitting near 3.3 mm, which have been previously characterized for laser performance. We extend the initial studies and report on the carrier recombination dynamics. The importance of carrier density motivates a careful examination of carrier density and quantum-well effects. SRH, radiative, and Auger recombination rates (A(SRH), B-rad, and C-Auger, respectively) were measured at 77 K and found to be A(SRH)(-1)approximate to 10 ns, B-rad approximate to 2 x 10(-10) cm(3) s(-1), and C-Auger less than or equal to 1.0 x 10(-29) cm(6) s(-1), respectively. At 150 K the nonradiative recombination coefficients increased to A(SRH)(-1) approximate to 1.7 ns, B-rad approximate to 0.78 x 10(-10) cm(3) s(-1) and C-Auger approximate to 7.0 x 10(-28) cm(6) s(-1), respectively. This study suggests InAsSb/InAlAsSb MQW diode laser performance may be limited by SRH nonradiative recombination mechanisms rather than Auger recombination. (C) 1998 American Institute of Physics. [S0003-6951(98)04846-3]. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. MIT, Lincoln Lab, Lexington, MA 02173 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Cooley, WT (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 28 TC 10 Z9 10 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD NOV 16 PY 1998 VL 73 IS 20 BP 2890 EP 2892 DI 10.1063/1.122620 PG 3 WC Physics, Applied SC Physics GA 136FW UT WOS:000076848700012 ER PT J AU Armstrong, T AF Armstrong, T TI Kincheloe crash detailed SO AVIATION WEEK & SPACE TECHNOLOGY LA English DT Letter C1 USAF, Long Beach, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL INC PI NEW YORK PA 1221 AVENUE OF THE AMERICAS, NEW YORK, NY 10020 USA SN 0005-2175 J9 AVIAT WEEK SPACE TEC JI Aviat. Week Space Technol. PD NOV 16 PY 1998 VL 149 IS 20 BP 6 EP 6 PG 1 WC Engineering, Aerospace SC Engineering GA 139TH UT WOS:000077045400003 ER PT J AU Shaughnessy, P Ririe, D Osswald, M Lewis, S AF Shaughnessy, P Ririe, D Osswald, M Lewis, S TI High dose chemotherapy with BICE (BCNU, ifosfamide, carboplatin, and etoposide) and autologous bone marrow transplantation for patients with Ewings Sarcoma (ES) SO BLOOD LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Dept Bone Marrow Transplant, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0006-4971 J9 BLOOD JI Blood PD NOV 15 PY 1998 VL 92 IS 10 SU 1 MA 4602 BP 372B EP 372B PN 2 PG 1 WC Hematology SC Hematology GA 141AX UT WOS:000077121401628 ER PT J AU Karna, SP AF Karna, SP TI Theory and calculations of electric field effects on hyperfine interactions SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article; Proceedings Paper CT International Symposium on Atomic, Molecular, and Condensed Matter Theory at the 38th Annual Sanibel Symposium CY FEB 21-27, 1998 CL ST AUGUSTINE, FLORIDA SP IBM Corp, HyperCube Inc, Q-Chem Inc, Univ Florida DE electric field effects; hyperfine interactions AB A recently published theory of electric field effects on electron spin resonance hyperfine couplings [Phys. Ref. Lett. 79, 379, (1997)] is extended to nuclear quadrupole coupling. With the use of the ab initio coupled Hartree-Fock approach and augmented Sadlej basis set, results are obtained for the first-order corrections to the isotropic and anisotropic parts of hyperfine coupling tensor and the electronic part of the electric field gradient tensor for O-17 and H-2 nuclei in OH radical. The first-order coefficients exhibit a number of interesting features. The calculated results, in general, appear to be insensitive to the bond-centered polarization functions used in the calculation. (C) 1998 John Wiley & Sons, Inc. C1 USAF, Res Lab, Space Elect & Protect Branch, Kirtland AFB, NM 87117 USA. RP Karna, SP (reprint author), USAF, Res Lab, Space Elect & Protect Branch, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. EM karnas@plk.af.mil NR 29 TC 3 Z9 3 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD NOV 15 PY 1998 VL 70 IS 4-5 BP 771 EP 778 DI 10.1002/(SICI)1097-461X(1998)70:4/5<771::AID-QUA23>3.3.CO;2-P PG 8 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 139CN UT WOS:000077010200023 ER PT J AU Amer, M Barsoum, MW El-Raghy, T Weiss, I Leclair, S Liptak, D AF Amer, M Barsoum, MW El-Raghy, T Weiss, I Leclair, S Liptak, D TI The Raman spectrum of Ti3SiC2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GRAPHITE AB In this paper, the Raman spectrum of Ti3SiC2 is reported and compared with that of TiC0.67. All the TiC0.67 first order Raman disorder-induced modes are active, but shifted, in Ti3SiC2. Two additional peaks at 150 and 372 cm(-1) are observed in Ti3SiC2. The former is ascribed to a shear mode between the Si and Ti planes; the origin of the latter is unknown. No second order Raman bands are detected. Micro-Raman spectroscopy also reveal the presence of approximate to 50 Angstrom graphite crystallites in samples hot pressed in graphite dies-these crystallites are not detected in samples processed by hot isostatic pressing in molten glass containers. (C) 1998 American Institute of Physics. [S0021-8979(98)06622- 5]. C1 Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. Drexel Univ, Dept Mat Engn, Philadelphia, PA 19104 USA. USAF, Res Lab, Mat Proc Design Branch, Dayton, OH 45435 USA. RP Amer, M (reprint author), Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. EM barsoumw@post.drexel.edu RI Amer, Maher/A-1802-2009 NR 19 TC 77 Z9 79 U1 2 U2 15 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 NOV 15 PY 1998 VL 84 IS 10 BP 5817 EP 5819 DI 10.1063/1.368849 PG 3 WC Physics, Applied SC Physics GA 133CP UT WOS:000076669100074 ER PT J AU Semiatin, SL Seetharaman, V Ghosh, AK Shell, EB Simon, MP Fagin, PN AF Semiatin, SL Seetharaman, V Ghosh, AK Shell, EB Simon, MP Fagin, PN TI Cavitation during hot tension testing of Ti-6A1-4V SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE hot tension; cavitation; coalescence ID SUPERPLASTIC DEFORMATION; TITANIUM-ALLOYS; CAVITY GROWTH; COALESCENCE AB Cavity initiation, growth, and coalescence phenomena during the hot tension testing of Ti-6Al-4V with several different transformed beta-microstructures were established to obtain an understanding of the failure process during subtransus hot working. Samples with either a colony-type microstructure (containing grain-boundary alpha) or a martensitic, acicular alpha-microstructure were pulled to failure at strain rates between 0.01 and 3 s(-1) and various subtransus temperatures ranging from 540 to 955 degrees C. Metallographic analysis of sectioned tension samples with colony microstructures revealed that cavity initiation occurred at very low strains (less than or similar to 0.2) irrespective of strain rate at temperatures below 900 degrees C due to an apparent incompatibility of deformation between the grain-boundary alpha-layer and the Widmanstatten side plates. Initiation strains were somewhat higher (similar to 0.2-0.5) for samples with the acicular alpha-microstructure tested at temperatures below 900 degrees C; however, failure was still intergranular. Subsequent cavity growth was more rapid for colony microstructures than that for the martensitic alpha-microstructure at these temperatures. Above 900 degrees C, however, substantially higher cavity initiation strains and lower cavity growth rates were obtained for both microstructures. These latter behaviors were ascribed to the presence of a large volume fraction of ductile beta-phase and moderate values of the strain-rate sensitivity of the flow stress, respectively. (C) 1998 Elsevier Science S.A. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, ARFL,MLLM, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Dayton, Dayton, OH 45469 USA. RP Semiatin, SL (reprint author), USAF, Res Lab, Mat & Mfg Directorate, ARFL,MLLM, Bldg 655,Suite 1,2230 10th St, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 22 TC 50 Z9 53 U1 0 U2 10 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 NOV 15 PY 1998 VL 256 IS 1-2 BP 92 EP 110 DI 10.1016/S0921-5093(98)00814-4 PG 19 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 142RF UT WOS:000077213600011 ER PT J AU Joshi, MP Swiatkiewicz, J Xu, FM Prasad, PN AF Joshi, MP Swiatkiewicz, J Xu, FM Prasad, PN TI Energy transfer coupling of two-photon absorption and reverse saturable absorption for enhanced optical power limiting SO OPTICS LETTERS LA English DT Article ID C60; C-60 AB We introduce a new approach to enhancing the optical power-limiting function at near-IR wavelength (similar to 800 nm) by coupling effective two-photon absorption in one molecule with excited-state absorption in another molecule. We experimentally demonstrate this approach by using a strong two-photon absorbing dye, AF-380, and a strong reverse saturable absorber, C(60). A nanosecond time-resolved experiment is used to show that energy transfer from AF-380 to C(60) generates triplet excitation in C(60) that further absorbs the pump beam to enhance the power-limiting function. (C) 1998 Optical Society of America. C1 SUNY Buffalo, Dept Phys, Photon Res Lab, Buffalo, NY 14260 USA. SUNY Buffalo, Dept Chem, Buffalo, NY 14260 USA. USAF, Wright Lab, Polymer Branch, WL MLBP Mat Directorate, Wright Patterson AFB, OH 45433 USA. Systran Corp, Dayton, OH 45432 USA. RP Joshi, MP (reprint author), SUNY Buffalo, Dept Phys, Photon Res Lab, Buffalo, NY 14260 USA. NR 14 TC 77 Z9 80 U1 3 U2 8 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD NOV 15 PY 1998 VL 23 IS 22 BP 1742 EP 1744 DI 10.1364/OL.23.001742 PG 3 WC Optics SC Optics GA 137GL UT WOS:000076906300006 PM 18091900 ER PT J AU Mailloux, RJ AF Mailloux, RJ TI Constrained feed technique for subarrays of large phased arrays SO ELECTRONICS LETTERS LA English DT Article AB A technique is presented which combines the subarraying qualities of constrained dual transform beamforming sections and partial overlapping networks to produce arrays of contiguous subarrays. This approach is shown to facilitate wideband scanning or limited field of view coverage with a minimum number of controls and low sidelobes. C1 USAF, Res Lab, Sensors Directorate, Bedford, MA 01731 USA. RP Mailloux, RJ (reprint author), USAF, Res Lab, Sensors Directorate, 31 Grenier St, Bedford, MA 01731 USA. NR 3 TC 3 Z9 4 U1 0 U2 0 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD NOV 12 PY 1998 VL 34 IS 23 BP 2191 EP 2193 DI 10.1049/el:19981584 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 143NW UT WOS:000077263100009 ER PT J AU Taverna, PJ Mayfield, O Andrews, ARJ AF Taverna, PJ Mayfield, O Andrews, ARJ TI Determination of cadmium ions in water by a novel electrochemiluminescence method SO ANALYTICA CHIMICA ACTA LA English DT Article ID ATOMIC-ABSORPTION SPECTROMETRY; ELECTROGENERATED CHEMILUMINESCENCE; STRIPPING VOLTAMMETRY; COMPLEXES; LEAD; TUNICATE; COPPER; CD; PB AB A new electrochemiluminescence (ECL) reaction in aqueous solution, involving cadmium(II) ions, is reported. The ECL reaction occurs in the presence of a common co-reactant, tripropylamine (TPA), and an organic ligand, 1,10-phenanthroline. The reaction is presumed to arise from the metal-ligand complex and co-reactant. Conditions for ECL emission were optimised and a calibration graph constructed. Emission was linear over the 50-1000 ppb range. The calculated limit of detection (LOD) was 5 ppb. The interference of other metal ions with the ECL reaction was also examined. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Tulane Univ, Dept BME, New Orleans, LA 70118 USA. AL EQ, Tyndall AFB, FL 32403 USA. Ohio Univ, Ctr Intelligent Chem Instrumentat, Dept Chem, Athens, OH 45701 USA. RP Andrews, ARJ (reprint author), Tulane Univ, Dept BME, 500 Lindy Boggs, New Orleans, LA 70118 USA. NR 17 TC 13 Z9 13 U1 3 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0003-2670 J9 ANAL CHIM ACTA JI Anal. Chim. Acta PD NOV 11 PY 1998 VL 373 IS 2-3 BP 111 EP 117 DI 10.1016/S0003-2670(98)00405-X PG 7 WC Chemistry, Analytical SC Chemistry GA 129QZ UT WOS:000076475600001 ER PT J AU Wang, FL Li, KWK Fuflyigin, V Jiang, H Zhao, J Norris, P Goldstein, D AF Wang, FL Li, KWK Fuflyigin, V Jiang, H Zhao, J Norris, P Goldstein, D TI Thin ferroelectric interferometer for spatial light modulations SO APPLIED OPTICS LA English DT Article ID PLZT; SILICON AB Thin ferroelectric interferometers (TFI's) for use as light-modulating devices were fabricated entirely with thin-film techniques on sapphire substrates. The ferroelectric layer in the TFI devices was a lead lanthanum zirconated titanate thin-film material, which can be formed from a chemical solution on highly reflective dielectric mirror surfaces. Light intensity modulation in both transmission and reflection modes was demonstrated with the fabricated devices. Experimental data and simulations show that TFI devices possess tremendous potential in spatial light modulators because of their fast-switching, low-driving voltage and readiness for integration with a variety of substrates, including silicon. (C) 1998 Optical Society of America. C1 NZ Appl Technol, Woburn, MA 01801 USA. USAF, Wright Lab, Eglin AFB, FL 32542 USA. RP Wang, FL (reprint author), NZ Appl Technol, 8A Gill St, Woburn, MA 01801 USA. NR 15 TC 16 Z9 16 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD NOV 10 PY 1998 VL 37 IS 32 BP 7490 EP 7495 DI 10.1364/AO.37.007490 PG 6 WC Optics SC Optics GA 137LK UT WOS:000076916100004 PM 18301583 ER PT J AU Cooper, TM Stone, MO AF Cooper, TM Stone, MO TI Investigation of self-assembly upon formation of an electrostatic complex of congo red and a helical peptide SO LANGMUIR LA English DT Article ID POLYPEPTIDE-DYE MULTILAYERS; CIBACRON BLUE; AZO DYES; CIRCULAR-DICHROISM; AMYLOID FIBRILS; BINDING; PROTEINS; DEHYDROGENASES; SPECTROSCOPY; CONFORMATION AB We have performed a detailed investigation of the solution-phase properties of the electrostatic complex formed between the sulfonated azo dye congo red (CR) and the peptide acetyl-YAAAKAAAAKAAAAKA-amide (YAK123). In contrast to amyloid, this complex had good solubility. Aqueous solutions of mixtures of YAK123 and CR at varying molar ratios n(YAK123)/n(CR) = R were prepared and characterized by UV/vis, CD, fluorescence, Raman, and CE techniques. End points in spectroscopic titrations of YAK123 into CR solutions identified two stoichiometries: YAX123*CR2 and YAK123*CR, designated as "1-2" and "1-1", respectively. When YAK123 was added to a CR solution, the UV/vis spectrum of CR underwent hypochromism and a blue shift characteristic of H aggregate formation. The UV/vis end point identified a 1-2 complex. In contrast, the fluorescence intensity of CR increased to an end point characteristic of a 1-1 complex. The Raman spectrum of CR had small decreases in the -C-N= and -N=N- stretch frequencies with increasing R with an end point characteristic of a 1-1 complex. From the CD spectrum of YAK123, the end point of the titration identified a 1-2 complex and an increase in helix content from 36% to 67% was observed. The induced CD spectrum of CR in the presence of YAK123 had four bands whose variation with R gave evidence for 1-2 and 1-1 complexes. When R < 0.5, two of the CD bands lacked an isosbestic point and the variation in their ellipticity ma;dma suggested aggregation of the 1-2 complex. The other two bands had an isosbestic point, and their behavior suggested the formation of an aggregated 1-1 complex. CE measurements of these mixtures showed a single band whose retention time varied with R. When R much less than 1, a 1-2 complex was identified. when R = 1, a 1-1 complex was observed. When R much greater than 1, there was predominantly free YAK123. From the spectroscopic data, the following equilibria were inferred. When R much less than 1, the 1-2 complex was in equilibrium With free CR. When 0 < R < 0.5, self-assembly to the aggregate (1-2), occurred. As R approached 0.5, free CR was consumed and bound CR formed cross-links between YAK123 molecules, leading to the multimer (1-2),(1-1),. As R approached 1, m approached 0 and the self-assembled complex became (1-1),. When R much greater than 1, there was mostly free YAK123. The results suggest peptides can be used as templates for dye aggregation, seeds for growth of large single crystals, or a component in a dipping solution used in preparing polyion multilayer films. C1 USAF, Res Lab, MLPJ, Wright Patterson AFB, OH 45433 USA. RP Cooper, TM (reprint author), USAF, Res Lab, MLPJ, 3005 P St Suite 1, Wright Patterson AFB, OH 45433 USA. NR 54 TC 47 Z9 47 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD NOV 10 PY 1998 VL 14 IS 23 BP 6662 EP 6668 DI 10.1021/la9806911 PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 138RY UT WOS:000076987600011 ER PT J AU Mann, RW Feather, ME Tumosa, CS Holland, TD Schneider, KN AF Mann, RW Feather, ME Tumosa, CS Holland, TD Schneider, KN TI A blue encrustation found on skeletal remains of Americans missing in action in Vietnam SO FORENSIC SCIENCE INTERNATIONAL LA English DT Article DE vivianite; bone; iron II phosphate; blue encrustation; MIA; taphonomy AB A blue encrustation was found on the repatriated remains of three U.S. Servicemen listed as missing in action (MIA) from Vietnam after 28 years. The identification and origin of the blue material was determined. Scanning electron microscopy with energy dispersive analysis and powder X-ray diffraction identified the material as the mineral vivianite, Fe-3(PO4)(2). 8H(2)O. Vivianite has been found often associated with fossilized bone and teeth, but this example is unusual in that it is only the second published forensic example of vivianite growing from human bone after such a short period of time. The presence of vivianite provides information leading to a more complete and accurate understanding of the taphonomic process associated with American MIA remains. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 USA, Cent Identificat Lab, Hickam AFB, HI 96853 USA. Smithsonian Inst, Conservat Analyt Lab, Washington, DC 20560 USA. RP Mann, RW (reprint author), USA, Cent Identificat Lab, 310 Worchester Ave, Hickam AFB, HI 96853 USA. NR 11 TC 13 Z9 14 U1 1 U2 2 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0379-0738 J9 FORENSIC SCI INT JI Forensic Sci.Int. PD NOV 9 PY 1998 VL 97 IS 2-3 BP 79 EP 86 DI 10.1016/S0379-0738(98)00026-7 PG 8 WC Medicine, Legal SC Legal Medicine GA 147NY UT WOS:000077574400001 PM 9871987 ER PT J AU Arnold, ST Viggiano, AA Morris, RA AF Arnold, ST Viggiano, AA Morris, RA TI Rate constants and product branching fractions for the reactions of H3O+ and NO+ with C-2-C-12 alkanes SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID TRACE GAS-ANALYSIS; ION; AIR; BREATH AB Gas-phase ion molecule reactions of H3O+ and NO+ with a number of C-2-C-12 alkanes have been studied using a variable temperature-selected ion flow tube instrument. Reaction rate constants and product branching fractions were measured at 300 K, and temperature dependences of the rate constants and product branching fractions for reactions of C-7 and C-8 alkanes were examined from 300 to 500 K. The threshold size for H3O+ reaction occurs at hexane, with the reaction rate constants increasing steadily with alkane size. Association is the predominant reaction channel at 300 K for C-3-C-12 alkanes, although these products thermally dissociate back into initial reactants between 300 and 400 K. The proton-transfer reaction channel is expected to be exothermic for large alkanes; however, this reaction channel does not proceed at the collision rate, nor are any direct proton-transfer product ions observed. The presence of smaller alkyl product ions suggests proton-transfer product ions may dissociate into smaller alkyl fragment ions and neutral alkanes. The threshold size for NO+ reaction with n-alkanes also occurs at hexane, and the reaction proceeds primarily via hydride transfer as previous experiments have indicated. However, a number of smaller product ions are also observed for the reactions of NO+ with all n-alkanes larger than butane, with the branching fraction of the nonhydride transfer product ions increasing with increasing alkane size. Together with our previously reported results regarding the reactions of various atmospheric ions with octane isomers, the present results indicate that H3O+, NO+, and O-2(+) are not suitable chemical ionization agents for analysis of hydrocarbon emissions. C1 USAF, Res Lab, Space Vehicles Directorate VSBP, Hanscom AFB, MA 01731 USA. RP Morris, RA (reprint author), USAF, Res Lab, Space Vehicles Directorate VSBP, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 19 TC 38 Z9 38 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD NOV 5 PY 1998 VL 102 IS 45 BP 8881 EP 8887 DI 10.1021/jp9815457 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 137VQ UT WOS:000076937700035 ER PT J AU John, R Buchanan, DJ Larsen, JM AF John, R Buchanan, DJ Larsen, JM TI Prediction of transverse fatigue behavior of unidirectionally reinforced metal matrix composites SO SCRIPTA MATERIALIA LA English DT Article C1 Univ Dayton, Res Inst, Struct Integr Div, Dayton, OH 45469 USA. USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RP John, R (reprint author), Univ Dayton, Res Inst, Struct Integr Div, Dayton, OH 45469 USA. NR 19 TC 1 Z9 1 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD NOV 3 PY 1998 VL 39 IS 11 BP 1529 EP 1536 DI 10.1016/S1359-6462(98)00342-X PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 139RC UT WOS:000077042300007 ER PT J AU Convertino, VA AF Convertino, VA TI Changes in peak oxygen uptake and plasma volume in fit and unfit subjects following exposure to a simulation of microgravity SO ACTA PHYSIOLOGICA SCANDINAVICA LA English DT Article DE bedrest; blood volume; fitness; fluid intake; microgravity; peak oxygen uptake; urine output ID BED REST; CARDIOVASCULAR-RESPONSES; BLOOD-VOLUME; EXERCISE; REDUCTION; CAPACITY AB To test the hypothesis that the magnitude of reduction in plasma volume and work capacity following exposure to simulated microgravity is dependent on the initial level of aerobic fitness, peak oxygen uptake ((V) over dot O-2peak) was measured in a group of physically fit subjects and compared with (V) over dot O-2peak in a group of relatively unfit subjects before and after 10 days of continuous 6 degrees head-down tilt (HDT). Ten fit subjects (40 +/- 2 year) with mean +/- SE (V) over dot O-2peak = 48.9 +/- 1.7 mL kg(-1) min(-1) were matched for age, height, and lean body weight with 10 unfit subjects ((V) over dot O-2peak = 37.7 +/- 1.6 mt kg(-1) min(-1)). Before and after HDT, plasma, blood. and red cell volumes and body composition were measured and all subjects underwent a graded supine cycle ergometer test to determine (V) over dot O-2peak period needed. Reduced (V) over dot O-2peak in fit subjects (-16.2%) was greater than that of unfit subjects (-6.1%). Similarly, reductions in plasma (-18.3%) and blood volumes (-16.0%) in fit subjects were larger than those of unfit subjects (blood volume = -5.6%; plasma volume = -6.6%). Reduced plasma volume was associated with greater negative body fluid balance during the initial 24 h of HDT in the fit group (912 +/- 154 mL) compared with unfit subjects (453 +/- 200 mL). The percentage change for (V) over dot O-2peak correlated with percentage change in plasma volume (r = +0.79). Following exposure to simulated microgravity, fit subjects demonstrated larger reductions in (V) over dot O-2peak than unfit subjects which was associated with larger reductions in plasma and blood volume. These data suggest that the magnitude of physical deconditioning induced by exposure to microgravity without intervention of countermeasures was influenced by the initial fitness of the subjects. C1 Armstrong Lab, Div Clin Sci, Physiol Res Branch, Brooks AFB, TX 78235 USA. RP Convertino, VA (reprint author), AOCY, AL, Phys Res Branch, 2507 Kennedy Circle, Brooks AFB, TX 78235 USA. NR 23 TC 3 Z9 3 U1 0 U2 2 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0001-6772 J9 ACTA PHYSIOL SCAND JI Acta Physiol. Scand. PD NOV PY 1998 VL 164 IS 3 BP 251 EP 257 PG 7 WC Physiology SC Physiology GA 143AY UT WOS:000077234000003 PM 9853012 ER PT J AU Katta, VR Roquemore, WM AF Katta, VR Roquemore, WM TI Simulation of dynamic methane jet diffusion flames using finite rate chemistry models SO AIAA JOURNAL LA English DT Article; Proceedings Paper CT AIAA 35th Aerospace Science Meeting / Nonlinear Dynamical Systems Symposium CY JAN 06-10, 1997 CL RENO, NEVADA SP Amer Inst Aeronaut & Astronaut, USAF, Off Sci Res, Sandia Natl Labs ID PREFERENTIAL DIFFUSION; HEAT AB Detailed calculations for methane jet diffusion flames under laminar and transitional conditions are made using an axisymmetric, time-dependent computational fluid dynamics code and different chemical kinetics models. Comparisons are made with experimental data for a steady-state flame and for two dynamic flames that are dominated by buoyancy-driven instabilities. The ability of the three chemistry models-namely, 1) the modified Peters mechanism without C-2 chemistry, 2) the modified Peters mechanism with C(2)chemistry, and 3) the Gas Research Institute's Version 1.2 mechanism-in predicting the structure of coaxial jet diffusion flames under different operating conditions is investigated. It is found that the modified Peters mechanisms with and without C-2 chemistry are sufficient for the simulation of jet diffusion flames for a wide range of fuel-jet velocities. Detailed images of the vortical structures associated with the low- and transitional-speed methane jet flames are obtained using the reactive-Mie-scattering technique. These images suggest that a counter rotating vortex is established upstream of the buoyancy-induced toroidal vortex in the low-speed-flame case and that the shear-layer vortices that develop in the transitional-speed flame are dissipated as they are convected downstream. The time dependent calculations made using the modified Peters chemistry model have captured these unique features of the buoyancy-influenced jet flames. Finally, the unsteady flame structures obtained at a given height are compared with the steady state flame structures. C1 Innovat Sci Solut Inc, Dayton, OH 45440 USA. USAF, Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. RP Katta, VR (reprint author), Innovat Sci Solut Inc, 2766 Indian Ripple Rd, Dayton, OH 45440 USA. EM vrkatta@anake.appl.wpafb.af.mil NR 33 TC 32 Z9 33 U1 1 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD NOV PY 1998 VL 36 IS 11 BP 2044 EP 2054 DI 10.2514/2.305 PG 11 WC Engineering, Aerospace SC Engineering GA 139EB UT WOS:000077014000014 ER PT J AU Meffert, JJ AF Meffert, JJ TI All thumbs SO AMERICAN FAMILY PHYSICIAN LA English DT Article C1 Brooke Army Med Ctr, Wilford Hall USAF Med Ctr, San Antonio, TX 78259 USA. RP Meffert, JJ (reprint author), Brooke Army Med Ctr, Wilford Hall USAF Med Ctr, San Antonio, TX 78259 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER ACAD FAMILY PHYSICIANS PI KANSAS CITY PA 8880 WARD PARKWAY, KANSAS CITY, MO 64114-2797 USA SN 0002-838X J9 AM FAM PHYSICIAN JI Am. Fam. Physician PD NOV 1 PY 1998 VL 58 IS 7 BP 1647 EP 1648 PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 139YB UT WOS:000077057900012 PM 9824961 ER PT J AU Danielson, DR Reinhard, KJ AF Danielson, DR Reinhard, KJ TI Human dental microwear caused by calcium oxalate phytoliths in prehistoric diet of the lower Pecos region, Texas SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Article DE phytolith; dental wear; Texas AB Recent research demonstrates that silica phytoliths of dietary origin are associated with microwear of human teeth. Previous research has shown that severe enamel microwear and dental wear characterizes Archaic hunter-gatherers in the lower Pecos region of west Texas. Calcium oxalate crystals are especially common in Archaic coprolites. The vast majority are derived from prickly pear and agave, which were the dietary staples in west Texas for 6,000 years. The calcium oxalate phytoliths are harder than enamel. Therefore, calcium oxalate crystals are the most likely source of previously documented dental microwear and wear in the lower Pecos region. (C) 1998 Wiley-Liss, Inc. C1 Univ Nebraska, Dept Anthropol, Lincoln, NE 68588 USA. Care Of Holland T, USA, Cent ID Lab, Hickman AFB, HI USA. RP Reinhard, KJ (reprint author), Univ Nebraska, Dept Anthropol, 126 Bessey Hall, Lincoln, NE 68588 USA. NR 29 TC 37 Z9 40 U1 0 U2 5 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PD NOV PY 1998 VL 107 IS 3 BP 297 EP 304 DI 10.1002/(SICI)1096-8644(199811)107:3<297::AID-AJPA6>3.0.CO;2-M PG 8 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 136HG UT WOS:000076852900006 PM 9821494 ER PT J AU van der Meer, JR Werlen, C Nishino, SF Spain, JC AF van der Meer, JR Werlen, C Nishino, SF Spain, JC TI Evolution of a pathway for chlorobenzene metabolism leads to natural attenuation in contaminated groundwater SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SP STRAIN P51; ACID-DEGRADING BACTERIA; PSEUDOMONAS-PUTIDA F1; MICROBIAL-DEGRADATION; XENOBIOTIC COMPOUNDS; NUCLEOTIDE-SEQUENCE; TOLUENE DEGRADATION; GENE-CLUSTER; BIODEGRADATION; 1,4-DICHLOROBENZENE AB Complete metabolism of chlorinated benzenes is not a feature that is generally found in aerobic bacteria but is thought to be due to a novel recombination of two separate gene clusters. Such a recombination could be responsible for adaptation of a natural microbial community in response to contamination with synthetic chemicals. This hypothesis was tested in a chlorobenzene (CB)-contaminated aquifer. CB-degrading bacteria from a contaminated site were characterized for a number of years by examining a combination of growth characteristics and DNA-DNA hybridization, PCR, and DNA sequence data. The genetic information obtained for the CB pathway of the predominant microorganism, Ralstonia sp. strain JS705, revealed a unique combination of (partially duplicated) genes for chlorocatechol degradation and genes for a benzene-toluene type of aromatic ring dioxygenase. The organism was detected in CB-polluted groundwater by hybridizing colonies cultivated on low-strength heterotrophic media with probes for the CB pathway. Southern hybridizations performed to determine the organization of the CB pathway genes and the 16S ribosomal DNA indicated that CB-degrading organisms isolated from different wells at the site were identical to JS705. Physiological characterization by the Biolog test system revealed some differences. The genes for the aromatic ring dioxygenase and dihydrodiol dehydrogenase of JS705 were detected in toluene and benzene degraders from the same site. Our results suggest that recent horizontal gene transfer and genetic recombination of existing genes between indigenous microorganisms were the mechanisms for evolution of the catabolic pathway. Evolution of the CB pathway seems to have created the capacity for natural attenuation of CB at the contaminated site. C1 USAF, Res Lab, MLQR, Tyndall AFB, FL 32403 USA. Swiss Fed Inst Environm Sci & Technol, EAWAG, CH-8600 Dubendorf, Switzerland. RP Spain, JC (reprint author), USAF, Res Lab, MLQR, 139 Barnes Dr,Ste 2, Tyndall AFB, FL 32403 USA. RI van der Meer, Jan Roelof/G-6610-2012 NR 52 TC 97 Z9 102 U1 2 U2 17 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD NOV PY 1998 VL 64 IS 11 BP 4185 EP 4193 PG 9 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 133PD UT WOS:000076694200010 ER PT J AU Clayton, AS Elston, DM Kennard, CD AF Clayton, AS Elston, DM Kennard, CD TI Slowly expanding abdominal plaque SO ARCHIVES OF DERMATOLOGY LA English DT Article ID DERMATOFIBROSARCOMA PROTUBERANS; SARCOMAS C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Clayton, AS (reprint author), Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0003-987X J9 ARCH DERMATOL JI Arch. Dermatol. PD NOV PY 1998 VL 134 IS 11 BP 1478 EP + PG 2 WC Dermatology SC Dermatology GA 139XZ UT WOS:000077057700028 PM 9828889 ER PT J AU Geeze, DS AF Geeze, DS TI Pregnancy and in-flight cosmic radiation SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID COMMERCIAL AVIATION; IONIZING-RADIATION; HEALTH-PHYSICS; MORTALITY; EXPOSURE; PILOTS; LEUKEMIA AB Cosmic radiation is an occupational hazard to commercial and military flight crews. Aside from the direct risk to aviators, this ionizing radiation is a hazard to the fetuses of pregnant crewmembers and passengers. Animal studies of low dose ionizing radiation exposures, and human studies following high dose exposures, suggest that pregnant aviators may inadvertently subject their fetuses to a risk of decreased cognitive capacity or frank mental retardation, as well as childhood leukemia. Flight attendants sometimes unknowingly exceed recommended maximum cosmic radiation doses to their fetuses, raising social, ethical, and legal issues. C1 USAF, Inspect Agcy, Kirtland AFB, NM USA. RP Geeze, DS (reprint author), USAF, 3938 Stockton Loop SE, Albuquerque, NM 87118 USA. NR 23 TC 6 Z9 6 U1 0 U2 2 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD NOV PY 1998 VL 69 IS 11 BP 1061 EP 1064 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 133PA UT WOS:000076693900006 PM 9819162 ER PT J AU Michaud, VJ Lyons, TJ Hansen, CM AF Michaud, VJ Lyons, TJ Hansen, CM TI Frequency of the "push-pull effect" in US Air force fighter operations SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article AB Background: Recent investigation into the push-pull effect (PPE), the reduction of +Gz tolerance when preceded by less than +1 Gz, has focused on centrifuge studies to demonstrate the presence of adverse cardiovascular responses. Maneuvers found to cause the Push-Pull Effect (PPEM) have not been studied previously in U.S. Air Force (USAF) fighter aircraft. The frequency of and extent to which PPEMs are performed in fighter aircraft are unknown. Methods: Head-up display (HUD) videotapes from F-15 and F-16 air combat training missions were reviewed for the presence of PPEMs. The frequency of engagements containing PPEMs and the magnitude of the Gz profiles were noted. Results: PPEMs were found in 11 to 67% of engagements reviewed, depending on the nature of the training mission, with an overall average of 32%. The PPEMs that were observed contained segments of less than +1 Ct, ranging on average from 0.0 to 0.5 Gz for an average of 3.5 to 5 s duration. Conclusions: PPEMs are present in air combat training missions performed by today's USAF fighter aircraft and represent an operationally significant source of risk for accidents. These findings support continued research into the physiologic response to PPE and the development of countermeasures. C1 USAF, Sch Aerosp Med, Brooks AFB, TX 78235 USA. RP Michaud, VJ (reprint author), USAF, Sch Aerosp Med, RAM 98,2602 W Gate Rd, Brooks AFB, TX 78235 USA. NR 10 TC 11 Z9 17 U1 1 U2 1 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 NOV PY 1998 VL 69 IS 11 BP 1083 EP 1086 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 133PA UT WOS:000076693900010 PM 9819166 ER PT J AU Glickman-Weiss, EL Hearon, CM Nelson, AG Day, R AF Glickman-Weiss, EL Hearon, CM Nelson, AG Day, R TI Does capsaicin affect physiologic and thermal responses of males during immersion in 22 degrees C? SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID COLD WATER; EXERCISE; THERMOREGULATION; 27-DEGREES-C; EXPOSURE AB Background: Capsaicin alters thermoregulation in adult rats by producing a dose-dependent fall in body temperature and metabolism. The present investigation examined the thermal and metabolic responses in males who were fed capsaicin (CAP: 2 mg.kg(-1) body weight) vs. a placebo (PL: a maltodextrin capsule) prior to immersion in cold water. Methods: Seven Caucasian males aged 20-28 yr were immersed in 22 degrees C twice (PL vs. CAP), for 120 min. The following were examined: metabolism (M; W.m(-2)), rectal temperature (Tre; degrees C), mean skin temperature ((T) over bar sk; degrees C), tissue insulation (I; degrees C.m(-2).W-1) and proportion of energy derived from carbohydrate (%CHO). Results: For M, Tre, I, and fsk there was no significant differences between treatments (PL vs. CAP) when the variables were pooled jointly over time. However, significant differences across time was detected for Tre (p = 0.0003), (T) over bar sk (p = 0.0147), and M (p = 0.0036). Values for %CHO demonstrate a main effect for treatment (p = 0.0210) suggesting the CAP (46.7 +/- 25.9%) treatment demonstrated a decreased reliance on carbohydrate utilization for energy provision as compared to the PL (75.0 +/- 21.9%) treatment. Additionally, the treatment x time interaction was significant (p = 0.0096) whereby, PL differed from CAP at 5 min only. Conclusion: From these data it appears that while M, Tre, and (T) over bar sk differed across time, a CAP (which differentially affected percent of energy derived from carbohydrate) feeding did not differentially affect the thermal and metabolic responses of males during acute cold water immersion. C1 Kent State Univ, Exercise Sci Lab, Kent, OH 44242 USA. Armstrong Lab, KRUG Life Sci, Brooks AFB, TX 78235 USA. Louisiana State Univ, Dept Kinesiol, Baton Rouge, LA 70803 USA. Brigham Young Univ, Div Math & Sci, Laie, HI USA. RP Glickman-Weiss, EL (reprint author), Kent State Univ, Exercise Sci Lab, 163E MACC Annex, Kent, OH 44242 USA. NR 27 TC 5 Z9 5 U1 1 U2 1 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 NOV PY 1998 VL 69 IS 11 BP 1095 EP 1099 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 133PA UT WOS:000076693900012 PM 9819168 ER PT J AU Lang, KA Pickard, JS AF Lang, KA Pickard, JS TI Peptic ulcer disease in the military aviator: A management approach SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article ID HELICOBACTER-PYLORI INFECTION; ERADICATION AB The recognition of Helicobacter pylori as etiologic for most cases of peptic ulcer disease requires a reevaluation of policies for flying eligibility and waiver status in affected aviators. We present a suggested algorithm for managing military aviators with ulcer disease. C1 Human Syst Ctr, Armstrong Lab, Div Clin Sci, Brooks AFB, TX USA. Wilford Hall USAF Med Ctr, Dept Gastroenterol, Lackland AFB, TX 78236 USA. RP Pickard, JS (reprint author), USAF, Internal Med Branch, 2507 Kennedy Circle, Brooks AFB, TX 78235 USA. NR 14 TC 1 Z9 1 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 NOV PY 1998 VL 69 IS 11 BP 1100 EP 1103 PG 4 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 133PA UT WOS:000076693900013 PM 9819169 ER PT J AU Michaud, VJ Lyons, TJ AF Michaud, VJ Lyons, TJ TI The "push-pull effect" and G-induced loss of consciousness accidents in the US Air Force SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article AB Background: A recent Canadian Forces CF-18 Hornet aircraft accident has focused interest on the push-pull effect (PPE). PPE has not previously been identified in U.S. Air Force (USAF) G-Induced Loss of Consciousness (G-LOC) Accidents. The presence of maneuvers known to cause the push-pull effect (PPEMs) that lead to G-LOC accidents suggests that PPE is operationally significant and is a potential cause of G-LOC accidents. Methods: USAF accident reports where G-LOC was found to be causal were reviewed for indications of a PPEM immediately prior to the G-LOC. Terminology in the narratives was used to indicate a PPEM in the accident sequences. Results: In 3 of 24 mishaps, the presence of a PPEM was highly probable, while another 4 mishaps were found to have a probable association with PPEMs. The probable presence of PPEMs represents a significant percentage (12.5-29%) of USAF G-LOC accidents. Conclusion: USAF G-LOC accident reports contained descriptions that indicated the presence of PPEMs in accident sequences. This finding suggests that the PPE is an operationally significant source of risk for accidents in USAF high-performance aircraft. C1 USAF, Sch Aerosp Med, Brooks AFB, TX 78235 USA. RP Michaud, VJ (reprint author), USAF, Sch Aerosp Med, RAM 98,2602 W Gate Rd, Brooks AFB, TX 78235 USA. NR 4 TC 18 Z9 32 U1 0 U2 1 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 NOV PY 1998 VL 69 IS 11 BP 1104 EP 1106 PG 3 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 133PA UT WOS:000076693900014 PM 9819170 ER PT J AU Pokorny, RA AF Pokorny, RA TI Using maximum-likelihood adaptive methods to estimate difference thresholds and points of subjective equality SO BEHAVIOR RESEARCH METHODS INSTRUMENTS & COMPUTERS LA English DT Article ID FORCED-CHOICE; PEST; PSYCHOPHYSICS; EFFICIENT; QUEST AB In studying perception, psychologists must sometimes estimate perceivers' difference thresholds and points of subjective equality (PSEs). To quickly estimate a threshold, one adaptive procedure that has been claimed to find thresholds with maximal efficiency is Pentland's Best PEST. Descriptions of Best PEST report its implementation in the finding of one point along the perceiver's psychometric function. To find a difference threshold (also called difference limen, or DL) and the PSE, two thresholds must be found (as two points are required to estimate the slope and intercept of the perceiver's psychometric function). This paper describes how to modify Best PEST so as to estimate any threshold along the perceiver's psychometric function and reports the results of simulations in which both the DL and the PSE are estimated. C1 USAF, Res Lab, HEAB, Brooks AFB, TX 78235 USA. RP Pokorny, RA (reprint author), USAF, Res Lab, HEAB, 7909 Lindbergh Dr, Brooks AFB, TX 78235 USA. EM pokorny@alhrm.brooks.af.mil NR 20 TC 2 Z9 2 U1 1 U2 2 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 USA SN 0743-3808 J9 BEHAV RES METH INS C JI Behav. Res. Methods Instr. Comput. PD NOV PY 1998 VL 30 IS 4 BP 624 EP 636 DI 10.3758/BF03209480 PG 13 WC Psychology, Mathematical; Psychology, Experimental SC Psychology GA 152MK UT WOS:000077781200009 ER PT J AU Kong, X Wilson, GF AF Kong, X Wilson, GF TI A new EOG-based eyeblink detection algorithm SO BEHAVIOR RESEARCH METHODS INSTRUMENTS & COMPUTERS LA English DT Article ID WORKLOAD AB Accurate and efficient operator functional state classification and assessment based on physiological data have many important applications ranging from operator monitoring to interaction and control of human/machine systems. Eyeblink characteristics are frequently used as physiological indicators for this purpose. In this paper, we describe an efficient and robust eyeblink detection algorithm based on, nonlinear analysis of the electrooculogram (EOG) signal. The performance of the algorithm was evaluated via data analysis results of several benchmark test sets in comparison with another eyeblink detection algorithm. C1 No Illinois Univ, Dept Elect Engn, De Kalb, IL 60115 USA. USAF, Res Labs, Wright Patterson AFB, OH 45433 USA. RP Kong, X (reprint author), No Illinois Univ, Dept Elect Engn, De Kalb, IL 60115 USA. NR 9 TC 14 Z9 14 U1 0 U2 0 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 USA SN 0743-3808 J9 BEHAV RES METH INS C JI Behav. Res. Methods Instr. Comput. PD NOV PY 1998 VL 30 IS 4 BP 713 EP 719 DI 10.3758/BF03209491 PG 7 WC Psychology, Mathematical; Psychology, Experimental SC Psychology GA 152MK UT WOS:000077781200020 ER PT J AU O'Keefe, KP Sanson, TG AF O'Keefe, KP Sanson, TG TI Elderly patients with altered mental status SO EMERGENCY MEDICINE CLINICS OF NORTH AMERICA LA English DT Article ID DEMENTIA; DELIRIUM; DISEASE; DEPRESSION; ROTTERDAM; DIAGNOSIS; EMERGENCY AB Mental status changes in the elderly are a source of concern and a challenge for the emergency physician. A variety of medical conditions and psychiatric disturbances are potential causes of those symptoms. Acute changes must be differentiated from mental status alterations occurring as a result of chronic conditions. This article focuses on the emergency evaluation, treatment, and differential diagnosis of this symptom complex. C1 Spring Hill Reg Hosp, Emergency Dept, Spring Hill, FL USA. 6th Med Grp, Med Serv Flight & Emergency Serv, MacDill AFB, FL USA. RP O'Keefe, KP (reprint author), 812 Lorena Rd, Lutz, FL 33549 USA. NR 41 TC 5 Z9 6 U1 0 U2 1 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0733-8627 J9 EMERG MED CLIN N AM JI Emerg. Med. Clin. N. Am. PD NOV PY 1998 VL 16 IS 4 BP 701 EP + DI 10.1016/S0733-8627(05)70029-8 PG 16 WC Emergency Medicine SC Emergency Medicine GA 147LQ UT WOS:000077569800003 PM 9889736 ER PT J AU Lawrence, LL AF Lawrence, LL TI The limping child SO EMERGENCY MEDICINE CLINICS OF NORTH AMERICA LA English DT Article ID SEPTIC ARTHRITIS; ABUSE SYNDROME; OSTEOMYELITIS; MANAGEMENT; PAIN; HIP AB A child who limps or complains of limb pain presents a diagnostic challenge for the emergency physician. Fortunately, only a few causes require emergency treatment. This article provides the physician with a systematic approach for evaluating these patients. Detailed discussion is provided for some of the more prevalent, urgent, and age-specific diagnoses of limb pain and limping. C1 Uniformed Serv Univ Hlth Sci, Dept Mil & Emergency Med, Bethesda, MD USA. RP Lawrence, LL (reprint author), Malcolm Grow Med Ctr, Dept Emergency Med, Andrews AFB, MD 20762 USA. NR 31 TC 9 Z9 9 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0733-8627 J9 EMERG MED CLIN N AM JI Emerg. Med. Clin. N. Am. PD NOV PY 1998 VL 16 IS 4 BP 911 EP + DI 10.1016/S0733-8627(05)70039-0 PG 20 WC Emergency Medicine SC Emergency Medicine GA 147LQ UT WOS:000077569800013 PM 9889746 ER PT J AU Robar, CA Poremba, JA Pelton, JJ Hudson, L Higby, K AF Robar, CA Poremba, JA Pelton, JJ Hudson, L Higby, K TI Current diagnosis and management of aldosterone-producing adenomas during pregnancy SO ENDOCRINOLOGIST LA English DT Review ID PRIMARY HYPER-ALDOSTERONISM AB Aldosterone-producing adenomas account for ap proximately 0.5% of all cases of hypertension, The incidence of aldosterone producing adenomas during pregnancy is much lower, as reflected by a total of 15 biochemically and pathologically confirmed case reports in the English literature. We report the diagnosis, surgical management, and outcome of a patient with an aldosterone producing adenoma suspected at 20 weeks gestation Uniquely, we document the biochemical profiles of aldosterone, plasma renin activity, and 18 hydroxycorticosterone before and after surgical resection of the aldosterone;producing adenoma and 6 weeks postpartum, Our case and compilation of the English literature demonstrate an historic trend toward enhanced confidence in diagnostic testing during pregnancy and, subsequently, early surgical referral. C1 Wilford Hall USAF Med Ctr, Dept Endocrinol & Metab, San Antonio, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Surg, San Antonio, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Obstet & Gynecol, San Antonio, TX 78236 USA. USAF Acad, Dept Obstet & Gynecol, Colorado Springs, CO 80840 USA. RP Robar, CA (reprint author), 81 MDOS SGOMM, 301 Fisher St,Room 1F118, Keesler AFB, MS 39534 USA. NR 18 TC 4 Z9 4 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 1051-2144 J9 ENDOCRINOLOGIST JI Endocrinologist PD NOV-DEC PY 1998 VL 8 IS 6 BP 403 EP 408 DI 10.1097/00019616-199811000-00003 PG 6 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA 148BL UT WOS:000077488300003 ER PT J AU Weiss, BL Soref, RA AF Weiss, BL Soref, RA TI Introduction to the issue on silicon-based optoelectronics SO IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS LA English DT Editorial Material C1 Univ Surrey, Sch Elect Engn Informat Technol & Math, Guildford GU2 5XH, Surrey, England. USAF, Res Lab, Sensors Directorate, AFRL SNHC, Hanscom AF Base, MA 01731 USA. RP Weiss, BL (reprint author), Univ Surrey, Sch Elect Engn Informat Technol & Math, Guildford GU2 5XH, Surrey, England. NR 0 TC 2 Z9 2 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 1077-260X J9 IEEE J SEL TOP QUANT JI IEEE J. Sel. Top. Quantum Electron. PD NOV-DEC PY 1998 VL 4 IS 6 BP 897 EP 898 DI 10.1109/JSTQE.1998.736072 PG 2 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 154RV UT WOS:000077903300001 ER PT J AU Friedman, L Soref, RA Sun, G Lu, YW AF Friedman, L Soref, RA Sun, G Lu, YW TI Theory of the strain-symmetrized silicon-based Ge-Si superlattice laser SO IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS LA English DT Article DE Ge; mid-infrared lasers; semiconductor lasers; Si; superlattices ID QUANTUM-WELLS AB A unipolar p-i-p silicon-based intersubband laser consisting of a symmetrically strained Ge-Si superlattice on a relaxed Si0.5Ge0.5 buffer layer is modeled and analyzed, The strain-symmetrization removes the limitation on the size of the superlattice. The procedure for calculating the in-plane energy dispersion is extended to a superlattice. Analysis of the inplane energy dispersion shows that the population inversion is local-in-k-space. For an 11 ML/11 ML superlattice (15.4 Angstrom/15.4 Angstrom), interminiband lasing between HH2 and HH1 is predicted at lambda = 2.2 mu m. From the envelope functions and material properties, the miniband lifetimes and laser gain are calculated. For a current density of 10 kA/cm(2), a gain of G(L) = 96/cm is calculated. Alternate structures with larger expected gains are considered, Quantum-parallel, quantum-cascade, and quantum-staircase lasing are examined. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. Univ Massachusetts, Dept Phys, Boston, MA 02125 USA. RP Friedman, L (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 9 TC 19 Z9 19 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 1077-260X J9 IEEE J SEL TOP QUANT JI IEEE J. Sel. Top. Quantum Electron. PD NOV-DEC PY 1998 VL 4 IS 6 BP 1029 EP 1034 DI 10.1109/2944.736106 PG 6 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 154RV UT WOS:000077903300018 ER PT J AU Cash, MA Habetler, TG Kliman, GB AF Cash, MA Habetler, TG Kliman, GB TI Insulation failure prediction in AC machines using line-neutral voltages SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article; Proceedings Paper CT Annual Meeting of the Industry-Applications-Society CY OCT 05-09, 1997 CL NEW ORLEANS, LA SP Ind Applicat Soc DE condition monitoring; insulation failure; predictive maintenance; turn-fault detection ID INDUCTION-MOTORS; STATOR AB This paper presents a novel technique to detect insulation failure in polyphase ac machines. The machine must be star connected and have the neutral accessible. The mathematical theory of the technique is provided and supported by an experimental validation-turn faults in the stator of an induction machine are detected from the algebraic sum of the three, instantaneous, line-neutral voltages. However, this voltage sum contains undesirable frequencies that decrease the sensitivity of the scheme. Bandpass filtering the voltage sum (around the fundamental) optimizes sensitivity by removing the harmonics that arise from core saturation, slot harmonics, etc. The design of the scheme makes it practically immune to false alarms attributable to varying load conditions, operating temperatures, and source voltage perturbations. It is shown that this technique is simpler in both theory and practice than other techniques based upon accurate calculations of sequence voltages and currents. The simplicity of this technique permits a low-cost implementation to flag a turn fault within a few cycles of the fundamental machine excitation. C1 Georgia Inst Technol, Sch Elect & Comp Engn, Atlanta, GA 30332 USA. GE Co, Corp Res & Dev, Controls Syst & Power Elect Lab, Schenectady, NY 12301 USA. RP Cash, MA (reprint author), USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. EM thabetler@ee.gatech.edu NR 16 TC 90 Z9 90 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD NOV-DEC PY 1998 VL 34 IS 6 BP 1234 EP 1239 DI 10.1109/28.738983 PG 6 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA 143LW UT WOS:000077258000006 ER PT J AU Rouse, WB Boff, KR AF Rouse, WB Boff, KR TI R & D/technology management: A framework for putting technology to work SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART C-APPLICATIONS AND REVIEWS LA English DT Article DE information systems; knowledge management; R & D management; technology management ID INNOVATION; PERFORMANCE; INFORMATION; SUCCESS; MARKET; DESIGN; MODEL AB This article summarizes and integrates the state of knowledge of R&D/technology management, The goal is to clarify what is known and discuss how this knowledge can be leveraged, The overall conclusion is that understanding at multiple levels is key to deeply understanding R&D/technology management, Further, these multiple levels of understanding can be integrated by considering information access and utilization throughout these processes. Specific conclusions are summarized in terms of key issues, central questions, and tradeoffs. C1 Enterprise Support Syst, Norcross, GA 30092 USA. USAF, Res Lab, Human Effectiveness Directorate, Materiel Command, Wright Patterson AFB, OH 45433 USA. RP Rouse, WB (reprint author), Enterprise Support Syst, Norcross, GA 30092 USA. EM rouse@mindspring.com NR 79 TC 6 Z9 7 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 1094-6977 J9 IEEE T SYST MAN CY C JI IEEE Trans. Syst. Man Cybern. Part C-Appl. Rev. PD NOV PY 1998 VL 28 IS 4 BP 501 EP 515 DI 10.1109/5326.725337 PG 15 WC Computer Science, Artificial Intelligence; Computer Science, Cybernetics; Computer Science, Interdisciplinary Applications SC Computer Science GA 131TE UT WOS:000076590700001 ER PT J AU Dimiduk, DM AF Dimiduk, DM TI Systems engineering of gamma titanium aluminides: impact of fundamentals on development strategy SO INTERMETALLICS LA English DT Article; Proceedings Paper CT Kyoto Workshop on High Temperature Intermetallic Compounds CY MAY 10-13, 1998 CL KYOTO, JAPAN SP Japan Soc Promot Sci, Res Future Program DE titanium aluminides; based on TiAl; compositional variations : effects; ductility; electronic structure; fatigue resistance and crack growth; mechanical properties; defects : point defects and dislocations; defect : theory; mechanical properties theory ID DISLOCATION MECHANISMS; TIAL ALLOYS; 1/2<110> DISLOCATIONS; DEFORMATION-BEHAVIOR; FAULT ENERGIES; YIELD STRESS; FRACTURE; CREEP; TRANSFORMATIONS; LAMELLAE AB In the late 1980's, research on gamma titanium aluminides focused on processing-structure-properties relationships. By the early 1990's, this research raised challenges to the 'conventional wisdom' regarding these materials. It was during this time period that the Structural Materials research group at the Materials Directorate constructed a research approach to these materials based upon a systems engineering analysis of alloy technology development. This approach contributed to the emergent successes of these materials and will play an important part in our development of new alloy systems. The approach incorporates analytical, computational and experimental research, over numerous material length and time scales, in parallel efforts. In so doing, the approach intrinsically couples science and engineering, lending insight into 'best paths' for engineering development. The integration of such knowledge forms the basis for the most relevant scientific inquiry, and efficient alloy technology development. This manuscript briefly summarizes some impacts of fundamental research on gamma alloys within our systems approach. A variety of scientific and engineering challenges remain to be solved, some of which are discussed. The findings may serve as a framework for future development efforts for other intermetallic systems. (C) 1998 Elsevier Science Limited. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLM,AFRL, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Mat & Mfg Directorate, MLLM,AFRL, Bldg 655,2230 10th St, Wright Patterson AFB, OH 45433 USA. NR 64 TC 19 Z9 20 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 EI 1879-0216 J9 INTERMETALLICS JI Intermetallics PD NOV-DEC PY 1998 VL 6 IS 7-8 BP 613 EP 621 DI 10.1016/S0966-9795(98)00038-7 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 139HH UT WOS:000077022100011 ER PT J AU Kim, YW AF Kim, YW TI Strength and ductility in TiAl alloys SO INTERMETALLICS LA English DT Article; Proceedings Paper CT Kyoto Workshop on High Temperature Intermetallic Compounds CY MAY 10-13, 1998 CL KYOTO, JAPAN SP Japan Soc Promot Sci, Res Future Program DE titanium aluminides; based on TiAl; mechanical properties at ambient temperature; fracture toughness; microstructure; mechanical testing ID GAMMA-TITANIUM ALUMINIDES; FRACTURE; CRYSTALS AB Tensile behavior of two-phase TiAl alloys at room temperature (RT) is analyzed for duplex and lamellar microstructural forms. The Hall-Fetch relationship with high constants in fully-lamellar material is explained as a combined function of grain-size and deformation-anisotropy. The low ductility and its inverse relationship with grain size are explained using the anisotropic tensile properties of lamellar structures and assuming that the fracture is controlled by the crack nucleation process involving the pile-ups of dislocations under shear stress. The crack initiation toughness and associated strains near the crack tip are used to explain the inverse relationship between ductility and toughness. (C) 1998 Published by Elsevier Science Limited. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Kim, YW (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 25 TC 116 Z9 127 U1 0 U2 28 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 J9 INTERMETALLICS JI Intermetallics PD NOV-DEC PY 1998 VL 6 IS 7-8 BP 623 EP 628 DI 10.1016/S0966-9795(98)00037-5 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 139HH UT WOS:000077022100012 ER PT J AU Hazzledine, PM AF Hazzledine, PM TI Coherency and loss of coherency in lamellar Ti-Al SO INTERMETALLICS LA English DT Article; Proceedings Paper CT Kyoto Workshop on High Temperature Intermetallic Compounds CY MAY 10-13, 1998 CL KYOTO, JAPAN SP Japan Soc Promot Sci, Res Future Program DE titanium aluminides; based on TiAl; elastic properties; yield stress; phase interfaces; mechanical properties; theory ID BEHAVIOR AB A grain of fully lamellar Ti-Al is modeled as a periodic multilayer which may contain any number of layers, each with different lattice parameters, different (isotropic) elastic constants and different thicknesses. Formulae are given for the coherence (plane) stress and strain tensors in any layer. The gamma layers all have inplane shears and a biaxial tension whereas the alpha(2) layers have principally a biaxial compression. The coherence stresses expected in various forms of fully coherent Ti-Al are tabulated. Estimates are made of the lamellar thicknesses at which the material becomes semi- or partially- coherent and of the residual coherence stresses in these materials. (C) 1998 Published by Elsevier Science Limited. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Hazzledine, PM (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 9 TC 28 Z9 28 U1 1 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 J9 INTERMETALLICS JI Intermetallics PD NOV-DEC PY 1998 VL 6 IS 7-8 BP 673 EP 677 DI 10.1016/S0966-9795(98)00034-X PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 139HH UT WOS:000077022100020 ER PT J AU Lin, MT Sy-Munoz, J Munoz, CA Goodacre, CJ Naylor, WP AF Lin, MT Sy-Munoz, J Munoz, CA Goodacre, CJ Naylor, WP TI The effect of tooth preparation form on the fit of procera copings SO INTERNATIONAL JOURNAL OF PROSTHODONTICS LA English DT Article ID TITANIUM RESTORATIONS; CROWN; ACCURACY; MARGINS; SYSTEMS; METAL AB Purpose: This study evaluated the marginal and internal adaptation of Procera copings using different tooth preparations. The variations comprised 4 finish line forms, 3 occlusal forms, 3 occlusocervical undulation forms to the proximal finish line, and 3 proximal auxiliary retention forms. Materials and Methods: One hundred twenty preparations were made and copings were fabricated, cemented, embedded in an epoxy resin, sectioned, and measured at 14 sites. Results: The feather-edge finish line had the highest mean external marginal opening (135 +/- 79 mu m), compared with the chamfer finish line (64 +/- 38 mu m), the 0.8-mm rounded shoulder (51 +/- 34 mu m), and the 0.5-mm rounded shoulder (68 +/- 56 mu m) All 3 forms of occlusal reduction produced comparable internal adaptation at the axial wall. Specimens with normal occlusal reduction had the best occlusal adaptation at the cusp tip but not to a statistically different degree from the exaggerated form. Variations in the vertical height of interproximal finish lines did not significantly affect marginal opening. However, proximal retentive features less than 2.5 mm wide and more than 0.5 mm deep cannot be accurately reproduced with the present Procera scanner tip. Conclusion: Feather-edge finish-fine forms, deep retentive grooves, and deep occlusal morphology are not well reproduced using this system, but all other finish-line forms and design variations are accurately and clinically acceptably reproduced using this system. C1 Loma Linda Univ, Sch Dent, Dept Restorat Dent, Loma Linda, CA 92350 USA. USAF, Dent Corps, Scott AFB, IL USA. RP Sy-Munoz, J (reprint author), Loma Linda Univ, Sch Dent, Dept Restorat Dent, Loma Linda, CA 92350 USA. NR 27 TC 32 Z9 32 U1 0 U2 1 PU QUINTESSENCE PUBL CO INC PI CAROL STREAM PA 551 NORTH KIMBERLY DR, CAROL STREAM, IL 60188-1881 USA SN 0893-2174 J9 INT J PROSTHODONT JI Int. J. Prosthodont. PD NOV-DEC PY 1998 VL 11 IS 6 BP 580 EP 590 PG 11 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 143YV UT WOS:000077285900007 PM 10023221 ER PT J AU Davidson, DF Bates, R Petersen, EL Hanson, RK AF Davidson, DF Bates, R Petersen, EL Hanson, RK TI Shock tube measurements of the equation of state of argon SO INTERNATIONAL JOURNAL OF THERMOPHYSICS LA English DT Article; Proceedings Paper CT 13th Symposium on Thermophysical Properties CY JUN 22-27, 1997 CL UNIV COLORADO, BOULDER, COLORADO SP Amer Soc Mech Engineers, Heat Transfer Div, Standing Comm Thermophys Properties, Natl Inst Stand & Technol, Chem Sci & Technol Lab, Phys & Chem Properties Div HO UNIV COLORADO DE argon; density; equation of state; high pressure; high temperature; infrared emission; P-p-T data; shock tube ID PRESSURES; GASES AB We have investigated the equation of state of argon at elevated temperatures and pressures using a new shock tube method. Temperatures in the range of 1280 to 1830 K, and pressures from 6 to 50 MPa were generated behind reflected shock waves in test gas mixtures of argon with trace amounts of CO and H-2 added. Density was determined from reflected shock pressure and incident shock speed measurements using the shock-jump relations. Temperature was determined From the modeling of the 4.7 sum infrared emission of the fundamental vibrational band of thermally-equilibrated CO. The experimentally determined argon P-rho-T data points are in good agreement with the static-cell data of LeCocq and an extrapolation of the equation of state of Stewart and Jacobsen. C1 Stanford Univ, Dept Mech Engn, Thermosci Div, High Temp Gasdynam Lab, Stanford, CA 94305 USA. USAF, Philips Labs, Edwards AFB, CA 93524 USA. RP Davidson, DF (reprint author), Stanford Univ, Dept Mech Engn, Thermosci Div, High Temp Gasdynam Lab, Stanford, CA 94305 USA. RI Petersen, Eric/M-3609-2014 OI Petersen, Eric/0000-0002-4572-5916 NR 10 TC 7 Z9 7 U1 0 U2 5 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0195-928X J9 INT J THERMOPHYS JI Int. J. Thermophys. PD NOV PY 1998 VL 19 IS 6 BP 1585 EP 1594 PG 10 WC Thermodynamics; Chemistry, Physical; Mechanics; Physics, Applied SC Thermodynamics; Chemistry; Mechanics; Physics GA 158ZR UT WOS:000078147800009 ER PT J AU Zha, GC Knight, D Smith, D AF Zha, GC Knight, D Smith, D TI Investigations of high-speed civil transport inlet unstart at angle of attack SO JOURNAL OF AIRCRAFT LA English DT Article ID BOUNDARY-CONDITIONS; BLEED AB The unstart transient of a high-speed civil transport mixed compression axisymmetric inlet at Mach 2 and 2-deg angle of attack was investigated numerically by using a three-dimensional time-accurate Navier-Stokes solver. The Baldwin-Lomax algebraic turbulence model and an extrapolation uniform mass bleed boundary condition for the slot bleed were employed. It is observed that, when an angle of attack is imposed, the how on the leeward side has a stronger compression than that at zero angle of attack. The strong compression reduces the Mach number upstream of the terminal shock and therefore makes the shock move upstream first on the leeward side. Tbe initial shock motion starts with the bifurcation of the terminal shock. The lower part of the split shock is stable because of the centerbody bleed, whereas the top part of the shock continues to travel upstream. When the terminal shock on the leeward side passes the bleed region, a separation is induced by the shock/boundary-layer interaction on the shoulder of the inlet centerbody, and the entire inlet is brought to unstart. The overall computed flowfield phenomena agree qualitatively with the experimental observations. C1 Rutgers State Univ, Dept Mech & Aerosp Engn, Ctr Computat Design, Piscataway, NJ 08854 USA. Rutgers State Univ, Dept Comp Sci, Ctr Computat Design, Piscataway, NJ 08854 USA. RP Zha, GC (reprint author), USAF, Res Lab, CFD Res Sect, Air Vehicle Directorate, Wright Patterson AFB, OH 45433 USA. NR 23 TC 11 Z9 16 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 NOV-DEC PY 1998 VL 35 IS 6 BP 851 EP 856 DI 10.2514/2.2404 PG 6 WC Engineering, Aerospace SC Engineering GA 148PX UT WOS:000077542000003 ER PT J AU Barnes, PN Kushner, MJ AF Barnes, PN Kushner, MJ TI Reactions in the afterglow of time modulated inductive discharges of Xe and I-2 mixtures SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ION-ION NEUTRALIZATION; SYSTEMS; IODINE; RATES AB An investigation was conducted using absorption and emission spectroscopy of the afterglow from rf inductive discharges in Xe/I-2 mixtures. RF power at 11.5 MHz was supplied to coils surrounding a cylindrical discharge cell. Total pressures were between 0.8 and 5.3 Torr. Measurements were made as a function of radius and time following the termination of the discharge. Results presented here indicate that in the afterglow the XeI* excimer is formed by highly excited It and ground state Xe. Evidence is also presented that ion-ion neutralization is a major precursor reaction for the formation of other excited species in the afterglow. (C) 1998 American Institute of Physics. [S0021-8979(98)03120-X]. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. RP Barnes, PN (reprint author), USAF, Res Lab, 2645 5th St Ste 13, Wright Patterson AFB, OH 45433 USA. RI Kushner, Mark/A-7362-2008; Kushner, Mark/D-4547-2015 NR 18 TC 4 Z9 4 U1 0 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 NOV 1 PY 1998 VL 84 IS 9 BP 4727 EP 4730 DI 10.1063/1.368799 PG 4 WC Physics, Applied SC Physics GA 128VF UT WOS:000076428500011 ER PT J AU Williams, S Chiu, YH Levandier, DJ Dressler, RA AF Williams, S Chiu, YH Levandier, DJ Dressler, RA TI Determination of photofragment ion translational energy and angular distributions in an octopole ion guide: A case study of the Ar-2(+) and (N2O center dot H2O)(+) cluster ions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CHARGE-TRANSFER COLLISIONS; ABSORPTION CROSS-SECTIONS; PHOTODISSOCIATION DYNAMICS; PHOTO-DISSOCIATION; MOLECULE REACTIONS; BEAM MEASUREMENTS; VECTOR CORRELATIONS; SPECTROSCOPY; EXCITATION; FRAGMENT AB The first measurement of ion photodissociation product recoil velocity and angular anisotropy in an octopole ion guide are presented. The experimental and numerical procedures required to obtain photofragment ion translational energy and angular distributions are discussed. Cluster ions are photodissociated in an octopole ion guide, and photofragment ion velocity distributions are measured using time-of-flight (TOF). The instrumental discrimination function is determined using guiding held variation (VAR). A validation study using the (2)Sigma(g)(+)<--(2)Sigma(u)(+) transition of Ar-2(+) probed at 300 nm and a photodissociation dynamics study of (N2O . H2O)(+) to form N2OH++OH, N2O++H2O, and H2O++N2O in the 458-657 nm range are presented. The H2O+ and N2O+ photofragment translational energy and angular distributions are derived, and new information regarding the photodissociation of the (N2O . H2O)(+) cluster ion is obtained. (C) 1998 American Institute of Physics. [S0021-9606(98)00541-8]. C1 USAF, Res Lab, VSBM, Hanscom AFB, MA 01731 USA. RP USAF, Res Lab, VSBM, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 57 TC 12 Z9 12 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD NOV 1 PY 1998 VL 109 IS 17 BP 7450 EP 7461 DI 10.1063/1.477367 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 132KY UT WOS:000076630100043 ER PT J AU Knipp, DJ Emery, BA Engebretson, M Li, X McAllister, AH Mukai, T Kokubun, S Reeves, GD Evans, D Obara, T Pi, X Rosenberg, T Weatherwax, A McHarg, MG Chun, F Mosely, K Codrescu, M Lanzerotti, L Rich, FJ Sharber, J Wilkinson, P AF Knipp, DJ Emery, BA Engebretson, M Li, X McAllister, AH Mukai, T Kokubun, S Reeves, GD Evans, D Obara, T Pi, X Rosenberg, T Weatherwax, A McHarg, MG Chun, F Mosely, K Codrescu, M Lanzerotti, L Rich, FJ Sharber, J Wilkinson, P TI An overview of the early November 1993 geomagnetic storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID EQUATORIAL SPREAD-F; SOLAR-WIND; IONOSPHERIC ELECTRODYNAMICS; MAGNETIC STORMS; POLAR-CAP; PHASE FLUCTUATIONS; PLASMA SHEET; MARCH 28-29; FIELD; THERMOSPHERE AB This paper describes the development of a major space storm during November 2-11, 1993. We discuss the history of the contributing high-speed stream, the powerful combination of solar wind transients and a corotating interaction region which initiated the storm, the high-speed flow which prolonged the storm and the near-Earth manifestations of the storm. The 8-day storm period was unusually long; the result of a high-speed stream (maximum speed 800 km/s) emanating from st distended coronal hole. Storm onset was accompanied by a compression of the entire dayside magnetopause to within geosynchronous Earth orbit(GEO). For nearly 12 hours the near-Earth environment was in a state of tumult. A super-dense plasma sheet was observed at GEO, and severe spacecraft charging was reported. The effects of electrons precipitating into the atmosphere penetrated into the stratosphere. Subauroral electron content varied by 100% and F layer heights oscillated by 200 km. Equatorial plasma irregularities extended in plumes to heights of 1400 km. Later, energetic particle fluxes at GEO recovered and rose by more than an order of magnitude. A satellite anomaly was reported during the interval of high energetic electron flux. Model results indicate an upper atmospheric temperature increase of 200 degrees K within 24 hours of storm onset. Joule heating for the first 24 hours of the storm was more than 3 times that for typical active geomagnetic conditions. We estimate that total global ionospheric heating for the full storm interval was similar to 190 PJ, with 30% of that generated within 24 hours of storm onset. C1 USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. NOAA, Space Environm Ctr, Boulder, CO 80303 USA. Natl Ctr Atmospher Res, High Altitude Observ, Boulder, CO 80307 USA. Augsburg Coll, Dept Phys, Minneapolis, MN 55454 USA. Nagoya Univ, Solar Terr Environm Lab, Aichi, Japan. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 229, Japan. Hiraiso Solar Terr Res Ctr, Ibaraki, Osaka, Japan. CALTECH, Jet Prop Lab, Pasadena, CA USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USAF, Res Lab, Space Vehicles Dirctorate, Hanscom AFB, MA 01731 USA. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. SW Res Inst, San Antonio, TX 78228 USA. IPS Radio & Space Serv, Haymarket, NSW, Australia. RP Knipp, DJ (reprint author), USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. EM knippdj.dfp@usafa.af.mil; emery@ncar.ucar.edu; engebret@augsburg.edu; lix@kitron.Colorado.edu; ahm@ncar.ucar.edu; mukai@fujitubo.gtl.isas.ac.jp; reeves@lanl.gov; T.Obara@crl.go.jp; xqp@cobra.jpl.nasa.gov; rosenberg@uap.umd.edu; allanw@polar.umd.edu; mchargmg.dfp@usafa.af.mil; chunflc.dfp@usafa.af.mil; codrescu@sec.noaa.gov; ljl@physics.belllabs.com; rich@plh.af.mil; sharb@broccoli.space.swri.edu; phil@ips.gov.au RI Reeves, Geoffrey/E-8101-2011 OI Reeves, Geoffrey/0000-0002-7985-8098 NR 92 TC 66 Z9 68 U1 0 U2 2 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 NOV 1 PY 1998 VL 103 IS A11 BP 26197 EP 26220 DI 10.1029/98JA00762 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500002 ER PT J AU McAllister, AH Knipp, DJ Crooker, NU Mukai, T Kokubun, S AF McAllister, AH Knipp, DJ Crooker, NU Mukai, T Kokubun, S TI Identification of solar drivers: The November 3-4, 1993, geomagnetic storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CORONAL MASS EJECTIONS; X-RAY TELESCOPE; MAGNETIC RECONNECTION; H-ALPHA; WIND; FILAMENT; TRANSIENTS; ULYSSES; PLASMA; FLARE AB Solar wind data at Earth and coronal soft X ray images are used to identify the probable solar sources for the November 3-4, 1993, geomagnetic storm. This storm falls in a recurrent sequence associated with the leading edge of a high speed stream from a large coronal hole. We have found convincing, though not certain, evidence that there were also two coronal mass ejections (CMEs) that contributed to the storm. The solar wind transients to which they gave rise arrived at Earth after passage of the heliospheric current sheet and in association with the corotating interaction region (CIR) at the leading edge of the high-speed stream. This combination of transients with a CIR at the leading edge of a new sector is an example of the dominant pattern for significant geomagnetic storms in the declining phase of the solar cycle. We suggest that global analysis, as used in this paper, can contribute to understanding the relative geoeffectiveness of different CMEs. C1 Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. Nagoya Univ, Solar Terr Environm Lab, Aichi 442, Japan. USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. Inst Space & Astronaut Sci, Sagamihara, Kanagawa 229, Japan. NCAR, High Altitude Observ, Boulder, CO USA. RP Helio Res, La Cresenta, CA 91214 USA. NR 69 TC 5 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9380 EI 2169-9402 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 1998 VL 103 IS A11 BP 26221 EP 26233 DI 10.1029/98JA01036 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500003 ER PT J AU Lui, ATY Williams, DJ McEntire, RW Christon, SP Galvin, AB Knipp, DJ AF Lui, ATY Williams, DJ McEntire, RW Christon, SP Galvin, AB Knipp, DJ TI Energetic ion composition and charge state of solar wind plasma during November 3, 1993, magnetic storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PARTICLES AB Measurements from the energetic particles and ion composition instrument on Geotail are used to investigate at high time resolution the ion composition and charge state of solar wind plasma (sampled in the magnetosheath) impacting the Earth during the geomagnetic storm which commenced on November 3, 1993. This storm is one in a series of recurrent storms associated with a high-speed stream from a large coronal hole. Significant changes in the ion composition were found to start at similar to 0300 UT on November 4, 1993, near the leading edge of the high-speed stream, becoming very conspicuous near similar to 0500 UT when the solar wind speed reached similar to 700 km/s. Changes noted include a large transient enhancement of He++ relative to Kf, a transient decrease in the temperatures of both H+ and He++ populations, an apparent enhancement of magnesium-silicon ions relative to iron ions, and a possible shift of iron ions to higher charge states. These changes may be associated with a coronal mass ejection embedded within the arrival of a new interplanetary sector. The time of these changes coincides well with the start of the second plunge in the Dsr index which ultimately leads to the minimum Dst for this geomagnetic storm, suggesting that these changes in composition and possibly charge state of the solar wind ions may be associated with factors which enhance the storm intensity at Earth. These results suggest that this magnetic storm may be exceptional for being a recurrent storm and yet being associated with CME activities for its intensity enhancement. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. USAF Acad, Dept Phys, Dept AF, Colorado Springs, CO 80840 USA. RP Lui, ATY (reprint author), Johns Hopkins Univ, Appl Phys Lab, 11100 Johns Hopkins Rd, Laurel, MD 20723 USA. RI Galvin, Antoinette/A-6114-2013; OI Christon, Stephen/0000-0003-1770-2458 NR 13 TC 0 Z9 0 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 NOV 1 PY 1998 VL 103 IS A11 BP 26235 EP 26242 DI 10.1029/97JA03730 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500004 ER PT J AU Kozyra, JU Jordanova, VK Borovsky, JE Thomsen, MF Knipp, DJ Evans, DS McComas, DJ Cayton, TE AF Kozyra, JU Jordanova, VK Borovsky, JE Thomsen, MF Knipp, DJ Evans, DS McComas, DJ Cayton, TE TI Effects of a high-density plasma sheet on ring current development during the November 2-6, 1993, magnetic storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOLAR-WIND; GEOSYNCHRONOUS ORBIT; GEOMAGNETIC STORMS; MODEL; MAGNETOSPHERE; PROTON; IONS; DYNAMICS; REGIONS; FIELDS AB The growth and recovery of the November 2-6, 1993 magnetic storm was simulated using a drift-loss ring current model that was driven by dynamic fluxes at geosynchronous orbit as an outer boundary condition. During the storm main phase, a high-density plasma sheet was observed by the Los Alamos National Laboratory geosynchronous satellites to move into and flow around the inner magnetosphere over a period of similar to 12 hours [Borovsky et al., 1997; this issue] during the storm main phase. Densities at the leading edge of this structure reached 3 cm(-3) as compared with more typical values <1 cm-3. The factor of 3 change in the plasma sheet density from quiet to active times produced a factor of 3 enhancement in the strength of the simulated ring current. In addition, a short-timescale recovery in the Dst index at 1600 UT on November 4 was driven by changes in the outer boundary condition and appeared even in the absence of collisional losses. An overshoot in the minimum Dst* occurred in the simulated ring current compared with observed values at similar to 0200 UT on November 4 and is taken as evidence of a loss process not included in the ring current-atmosphere interaction model (RAM). The storm onset was associated with a compression of the entire dayside magnetopause to within geostationary orbit starting at 2307 UT and continuing for a half hour. It is suggested that a possible additional loss may have resulted as ions drifted to the compressed dayside magnetopause. In fact such losses were found in another simulation of the inner magnetosphere for the same storm by Freeman et al. [1996]. The energy supplied to the inner magnetosphere, relative to the total energy input during this magnetic storm, was examined by comparing two widely used energy input functions, the epsilon parameter [Akasofu, 1981] and the F parameter [Burton et al., 1975] against energy input to the ring current model based on geosynchronous plasma observations at the outer boundary. It is found that the epsilon parameter [Akasofu,1981] overestimates the ring current energy input compared to the drift-loss model by almost an order of magnitude during the main phase. However, the integrated energy input from epsilon, over the 4 day interval of the storm, is in very good agreement with the total energy input inferred from observations. On the other hand, F more closely approximates the magnitude of the ring current energy input alone as calculated in the drift-loss model. An energy budget is constructed for the storm that shows energy inputs from the solar wind and energy dissipation due to ring current buildup and decay, auroral electron precipitation, Joule heating, ion precipitation, and energy storage in the magnetotail in reasonable balance. The ring current energy input accounts for only 15% of the total dissipated energy in this storm interval. A more complete energy budget that extends to November 11,1993, was compiled by Knipp et al. [this issue]. C1 Univ Michigan, Dept Atmospher Ocean & Space Sci, Space Phys Lab, Ann Arbor, MI 48109 USA. Univ Calif Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Astrophys & Radiat Measurements Grp, Los Alamos, NM 87545 USA. NOAA, Natl Ctr Environm Predict, Space Environm Ctr, Boulder, CO 80303 USA. Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. RP Kozyra, JU (reprint author), Univ Michigan, Dept Atmospher Ocean & Space Sci, Space Phys Lab, 2455 Hayward St, Ann Arbor, MI 48109 USA. OI Jordanova, Vania/0000-0003-0475-8743 NR 39 TC 94 Z9 93 U1 0 U2 2 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 NOV 1 PY 1998 VL 103 IS A11 BP 26285 EP 26305 DI 10.1029/98JA01964 PG 21 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500009 ER PT J AU Hairston, MR Heelis, RA Rich, FJ AF Hairston, MR Heelis, RA Rich, FJ TI Analysis of the ionospheric cross polar cap potential drop using DMSP data during the National Space Weather Program study period SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID CONVECTION; FIELD AB During the National Space Weather Program (NSWP) event study period of November 2-11, 1993 there were three operational DMSP meteorological satellites (F8, F10, and F11) in orbit, each carrying the Special Sensor for Ions, Electrons, and Scintillation (SSIES) plasma instrument package. Ion flow data from these instruments are used to determine the electrostatic potential drop across both the northern and southern polar caps. The magnitude and distribution of the potential are used to characterize the convection patterns present in the polar ionospheres. The results from all three satellites are presented to show an overall observational history of the potential drop and the convection pattern during the study period. These observational parameters provide crucial inputs and checks to several ionospheric and magnetospheric models being used in this study. Evidence is presented of an unambiguous difference in the cross polar cap potential drop between the two hemispheres for an extended period of time. C1 Univ Texas, William B Hanson Ctr Space Sci, Richardson, TX 75083 USA. USAF, Res Lab, VSBP, Space Vehicle Directorate, Hanscom AFB, MA 01731 USA. RP Hairston, MR (reprint author), Univ Texas, William B Hanson Ctr Space Sci, POB 830688, Richardson, TX 75083 USA. OI Hairston, Marc/0000-0003-4524-4837 NR 11 TC 28 Z9 28 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 NOV 1 PY 1998 VL 103 IS A11 BP 26337 EP 26347 DI 10.1029/97JA03241 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500012 ER PT J AU Borovsky, JE Thomsen, MF McComas, DJ Cayton, TE Knipp, DJ AF Borovsky, JE Thomsen, MF McComas, DJ Cayton, TE Knipp, DJ TI Magnetospheric dynamics and mass flow during the November 1993 storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID GEOSYNCHRONOUS ORBIT; MAGNETOPAUSE CROSSINGS; OUTER PLASMASPHERE; SYNCHRONOUS ORBIT; 6.6 RE; SPACE; PREDICTION; ANALYZER; GEOS-2; SHEET AB The National Space Weather Program (NSWP) Storm that occurred in November 1993 is examined with the use of plasma and energetic-particle measurements on three satellites in geosynchronous orbit. Geosynchronous orbit affords a powerful perspective on magnetospheric dynamics since both tail and dipole processes can be regularly seen, as well as nightside and dayside processes. The major magnetospheric regions analyzed before, during, and after this storm are the outer plasmasphere, the ion plasma sheet, the electron plasma sheet, and the outer electron radiation belt. Ionospheric outflows into the magnetosphere are also observed, and during the storm the magnetosheath and the low-latitude boundary layer are both seen briefly. The geosynchronous observations indicate that prior to the storm the magnetosphere was very quiet and the outer plasmasphere was filled out to beyond geosynchronous orbit. Extremely large anisotropies were seen in the ion plasma sheet during a compression phase just prior to storm onset. During the storm's main phase the drainage of the outer plasmasphere to the dayside magnetopause was observed, a superdense ion plasma sheet was tracked moving around the dipole, and a superdense electron plasma sheet was seen. The anomalousIy large plasma pressure on the nightside led to a beta > 1 situation at geosynchronous orbit. The beta > 1 region spread around the dipole with the superdense ion plasma sheet. The magnetic-field tilt angle at geosynchronous orbit indicated that strong cross-tail currents were present very near the Earth. These currents appear to be associated with plasma diamagnetism. Geosynchronous observations indicate that magnetospheric convection was extremely strong. In the electron plasma sheet, severe spacecraft charging occurred. The density of relativistic electrons was observed to peak very early in the storm, whereas the flux of these relativistic electrons peaked much later in the aftermath of the storm. C1 Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. USAF Acad, Dept Phys, Colorado Springs, CO 80840 USA. Los Alamos Natl Lab, Astrophys & Radiat Measurements Grp, Los Alamos, NM 87545 USA. RP Borovsky, JE (reprint author), Los Alamos Natl Lab, Space & Atmospher Sci Grp, Mail Stop D466, Los Alamos, NM 87545 USA. EM jborousky@lanl.gov NR 40 TC 43 Z9 43 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD NOV 1 PY 1998 VL 103 IS A11 BP 26373 EP 26394 DI 10.1029/97JA03051 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 133UX UT WOS:000076705500016 ER PT J AU Alam, MK Semiatin, SL Ali, Z AF Alam, MK Semiatin, SL Ali, Z TI Thermal stress development during vacuum arc remelting and permanent mold casting of ingots SO JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB The development of thermal stresses in ingots during the vacuum are remelting (VAR) as well as specialized permanent mold casting (PMC) process was modeled via numerical solution of the two-dimensional, nonsteady-state head conduction and stress equilibrium equations. The numerical analysis was carried out in conjunction with experimental studies of the mechanical properties and microstructure of a cracked VAR titanium aluminide ingot. Numerical solutions were obtained for different values of ingot diameter, crucible-ingot interface heat transfer coefficients, and lengths of the melted-and-resolidified ingot. For both VAR and PMC, model predictions revealed that the maximum tensile thermal stresses are developed at the bottom of the ingot; the magnitude of such stresses increases with ingot diameter and the magnitude of the interface heat transfer coefficients. The microstructural analysis of a cracked ingot indicated that the thermal cracking occurred in the temperature range where the alloy has very little ductility. The predicted development of large tensile stresses correlates well with observations of thermal cracking during VAR of near-gamma titanium aluminide alloy ingots. By contrast, the predicted thermal stresses developed during PMC are lower, thus suggesting an attractive alternative to VAR to obtain sound, crack-free ingots. C1 Ohio Univ, Dept Engn Mech, Athens, OH 45701 USA. AFRL, MLLM, Wright Patterson AFB, OH USA. Ohio Univ, Dept Engn Mech, Athens, OH 45701 USA. RP Alam, MK (reprint author), Ohio Univ, Dept Engn Mech, Athens, OH 45701 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 11 TC 1 Z9 2 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1087-1357 J9 J MANUF SCI E-T ASME JI J. Manuf. Sci. Eng.-Trans. ASME PD NOV PY 1998 VL 120 IS 4 BP 755 EP 763 DI 10.1115/1.2830216 PG 9 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 144VU UT WOS:000077336700012 ER PT J AU Dutton, RE Goetz, RL Shamasundar, S Semiatin, SL AF Dutton, RE Goetz, RL Shamasundar, S Semiatin, SL TI The ring test for P/M materials SO JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID CONSOLIDATION; POWDER AB The application of the ring test to assess die-workpiece interface friction during forging of powder metallurgical materials has been investigated. As for fully dense materials, the change in internal diameter as a function of height reduction was used to quantify friction. To this end calibration curves were generated by conducting finite element method (FEM) simulations of ring forging with different friction factors. The method was validated by conducting isothermal, hot compression tests on rings of an alpha-two titanium aluminide alloy with starting densities of 75, 85, dr 100 percent of full theoretical density. Comparison of the test data to the calibration curves revealed somewhat higher friction factors for the porous materials (as compared to the fully dense material) for both lubricated and unlubricated interface conditions. Furthermore, the accuracy of the FEM simulations of the ring test was confirmed by, good agreement between measured and predicted density distributions and load-stroke curves for tests on the porous titanium aluminide material. C1 Wright Lab, WL, MLLM, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Dutton, RE (reprint author), Wright Lab, WL, MLLM, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 18 TC 14 Z9 14 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1087-1357 J9 J MANUF SCI E-T ASME JI J. Manuf. Sci. Eng.-Trans. ASME PD NOV PY 1998 VL 120 IS 4 BP 764 EP 769 DI 10.1115/1.2830217 PG 6 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 144VU UT WOS:000077336700013 ER PT J AU Berg, JM Frazier, WG Chaudhary, A Banda, SS AF Berg, JM Frazier, WG Chaudhary, A Banda, SS TI Optimal open-loop ram velocity profiles for isothermal forging: A variational approach SO JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID DEFORMATION AB This paper considers the problem of selecting the ram velocity profile in an isothermal forging, to best obtain a desired material microstructure. This is to be accomplished by tracking a prescribed strain rate profile. A weighting function, reflecting the rate at which the microstructure is transforming, describes the relative importance of different parts of the billet, Finding the optimal solution generally requires a search over an infinite-dimensional function space. However, for a certain class of forgings the task reduces to solving a single ordinary differential equation. The result is a globally optimal and unique ram velocity profile. The method is demonstrated for the simulated forging of a TiAl turbine disk. C1 Texas Tech Univ, Dept Mech Engn, Lubbock, TX 79409 USA. USAF, Wright Lab, WL, MLIM, Wright Patterson AFB, OH 45433 USA. Appl Optimizat, Centerville, OH 45458 USA. USAF, Wright Lab, WL, FIGC, Wright Patterson AFB, OH 45433 USA. RP Berg, JM (reprint author), Texas Tech Univ, Dept Mech Engn, Lubbock, TX 79409 USA. EM jberg@ttu.edu NR 24 TC 5 Z9 5 U1 1 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1087-1357 J9 J MANUF SCI E-T ASME JI J. Manuf. Sci. Eng.-Trans. ASME PD NOV PY 1998 VL 120 IS 4 BP 774 EP 780 DI 10.1115/1.2830220 PG 7 WC Engineering, Manufacturing; Engineering, Mechanical SC Engineering GA 144VU UT WOS:000077336700015 ER PT J AU Powers, DB Morrison, JW AF Powers, DB Morrison, JW TI Middle cerebral artery aneurysm misdiagnosed as a temporomandibular disorder: Report of a case SO JOURNAL OF ORAL AND MAXILLOFACIAL SURGERY LA English DT Article C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. David Grant Med Ctr, Dept Oral & Maxillofacial Surg, Travis AFB, CA USA. RP Powers, DB (reprint author), Wilford Hall USAF Med Ctr, 59 Med Wing MRDO,2200 Berquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 4 TC 0 Z9 0 U1 0 U2 1 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0278-2391 J9 J ORAL MAXIL SURG JI J. Oral Maxillofac. Surg. PD NOV PY 1998 VL 56 IS 11 BP 1346 EP 1349 DI 10.1016/S0278-2391(98)90620-6 PG 4 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 136JN UT WOS:000076855800027 PM 9820224 ER PT J AU Ogawa, AM Shikora, SA Burke, LM Heetderks-Cox, JE Bergren, CT Muskat, PC AF Ogawa, AM Shikora, SA Burke, LM Heetderks-Cox, JE Bergren, CT Muskat, PC TI The thermodilution technique for measuring resting energy expenditure does not agree with indirect calorimetry for the critically ill patient SO JOURNAL OF PARENTERAL AND ENTERAL NUTRITION LA English DT Article ID TOTAL PARENTERAL-NUTRITION; GAS-EXCHANGE; GLUCOSE; SYSTEM AB Background: The complications associated with overfeeding critically ill patients are well documented. Indirect calorimetry is touted as the gold standard for measuring resting energy expenditure (REE). Unfortunately, the device is expensive, and many centers do not have this technology. The thermodilution technique for measuring cardiac output and calculating REE using the Fick equation has been reported to be an acceptable alternative. This study compared these techniques in a critically ill population. Methods: Forty consecutive patients with indwelling Swan-Ganz catheters in the surgical intensive care unit were prospectively studied while under the consultative care of the nutrition support service. REE was determined in all patients by both techniques within a 2-hour period. An error of 5% (approximately +/-100 kcal/d) between the two methods was deemed acceptable for clinical use. Results: Mean values for REE were 1928 +/- 558 vs 1898 +/- 518 kcal/d for the indirect calorimetry and thermodilution methods, respectively, and were not significantly different. However, there was great variation between the two techniques for the majority of patients such that REE determinations did not agree (t = 6.8; p <.0005). In 70% of the patients, REE determinations differed by greater than or equal to 20% and in 10% of the patients by 50%: Additionally, the greater the difference between the two methods, the more the thermodilution method tended to overestimate REE. Conclusions: When compared with indirect calorimetry in a critically ill population, the thermodilution method demonstrated an intersubject variability that is unacceptable for clinical use. C1 Wilford Hall USAF Med Ctr, Nutr Med Div, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Surg, Lackland AFB, TX 78236 USA. RP Ogawa, AM (reprint author), CNSD, Hlth & Wellness Ctr, 11th Wing,238 Brookley Ave, Washington, DC 20332 USA. NR 23 TC 7 Z9 7 U1 0 U2 0 PU AMER SOC PARENTERAL & ENTERAL NUTRITION PI SILVER SPRING PA 8630 FENTON STREET SUITE 412, SILVER SPRING, MD 20910 USA SN 0148-6071 J9 JPEN-PARENTER ENTER JI J. Parenter. Enter. Nutr. PD NOV-DEC PY 1998 VL 22 IS 6 BP 347 EP 351 DI 10.1177/0148607198022006347 PG 5 WC Nutrition & Dietetics SC Nutrition & Dietetics GA 136AZ UT WOS:000076836600003 PM 9829606 ER PT J AU Horwitz, JR Cofer, BR Warner, BW Cheu, HW Lally, KP AF Horwitz, JR Cofer, BR Warner, BW Cheu, HW Lally, KP TI A multicenter trial of 6-aminocaproic acid (Amicar) in the prevention of bleeding in infants on ECMO SO JOURNAL OF PEDIATRIC SURGERY LA English DT Article; Proceedings Paper CT 31st Annual Meeting of the Pacific-Association-of-Pediatric-Surgeons CY JUN 09-13, 1998 CL MAUI, HAWAII SP Pacific Assoc Pediat Surgeons DE epsilon-aminocaproic acid; extracorporeal membrane oxygenation; intracranial hemorrhage; thrombosis ID EXTRACORPOREAL MEMBRANE-OXYGENATION; NEONATAL RESPIRATORY-FAILURE; EPSILON-AMINOCAPROIC ACID; LIFE-SUPPORT ORGANIZATION; INTRACRANIAL HEMORRHAGE; CARDIAC-SURGERY; NEWBORNS; COMPLICATIONS; FIBRINOLYSIS; EXPERIENCE AB Background/Purpose: Intracranial hemorrhage (ICH), is a major source of morbidity and the leading cause of death in neonates treated with extracorporeal membrane oxygenation [ECMO). Anecdotal reports have suggested that epsilon-aminocaproic acid (EACA) can decrease the risk of ICH. The purpose of this study was to evaluate, in a multiinstitutional, prospective, randomized, blinded fashion, the effect of EACA on the incidence of hemorrhagic complications in neonates receiving ECMO. Methods: All neonates (except congenital diaphragmatic hernia) who met criteria for ECMO at three institutions were eligible for enrollment. EACA (100 mg/kg) or placebo was given at the time of cannulation followed by 25 mg/kg/h for 72 hours. Bleeding complications, transfusion requirements, and thrombotic complications were recorded. Post-ECMO imaging included head ultrasound scan computed tomography (CT) scan, and duplex ultrasound scan of the inferior vena cava and renal vessels. Results: Twenty-nine neonates were enrolled (EACA, 13 and placebo, 16). Five (17.2%) patients had a significant (grade 3 or larger) ICH. There was no statistical difference in the incidence of significant ICH in patients who received EACA (23%] versus placebo (12.5%). Septic patients accounted for all of the ICH in the EACA group. Thrombotic complications (aortic thrombus and SVC syndrome) developed in two patients from the placebo group. There was no difference in thrombotic circuit complications between groups. Conclusions: Our results suggest that the use of EACA in neonates receiving ECMO is safe but may not decrease the overall incidence of hemorrhagic complications. Copyright (C) 1998 by W.B. Saunders Company. C1 Univ Texas, Sch Med, Houston, TX USA. Hermann Childrens Hosp, Houston, TX USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Childrens Hosp, Med Ctr, Cincinnati, OH 45229 USA. RP Lally, KP (reprint author), Div Pediat Surg, 6431 Fannin,Suite 5-258, Houston, TX 77030 USA. FU NCRR NIH HHS [MO1 RR 02558, MO1 RR 00997] NR 24 TC 27 Z9 27 U1 1 U2 2 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0022-3468 J9 J PEDIATR SURG JI J. Pediatr. Surg. PD NOV PY 1998 VL 33 IS 11 BP 1610 EP 1613 DI 10.1016/S0022-3468(98)90591-7 PG 4 WC Pediatrics; Surgery SC Pediatrics; Surgery GA 141FF UT WOS:000077131500006 PM 9856877 ER PT J AU Frye, PE Kennedy, FG AF Frye, PE Kennedy, FG TI Reusable orbital transfer vehicle applications of an integrated solar upper stage SO JOURNAL OF PROPULSION AND POWER LA English DT Article; Proceedings Paper CT AIAA/ASME/SAE/ASEE 33rd Joint Propulsion Conference CY JUL 06-09, 1997 CL SEATTLE, WASHINGTON SP Amer Inst Aeronaut & Astronaut, ASME, SAE, ASEE AB There has been resurgent interest in the development of a reusable orbit transfer vehicle, based in low-Earth-orbit, for satellite placement, repositioning, recovery and control. An integrated solar upper-stage system is examined for several near-Earth applications, including low-Earth to geosynchronous to low-Earth orbit ferrying, An integrated solar upper stage (a solar thermal power and propulsion system) permits rapid access to high orbits because of its moderate thrust levels (tens to hundreds of pounds) at specific impulses approaching 900 s, intermediate between high-performance chemical propulsion and electrical propulsion systems. An integrated solar upper-stage reusable orbit transfer vehicle can be used in two novel modes: 1) Drag return, in which large, rigid solar concentrators provide an aeroassist capability lowering total delta-V requirements; and 2) a hybridized integrated solar upper stage, coupled with and providing power to a xenon ion thruster, allowing more efficient maneuvers in nontime critical applications. C1 Boeing Co, Rocketdyne Prop & Power, Canoga Park, CA 91309 USA. USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Frye, PE (reprint author), Boeing Co, Rocketdyne Prop & Power, POB 7922, Canoga Park, CA 91309 USA. NR 7 TC 0 Z9 0 U1 1 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD NOV-DEC PY 1998 VL 14 IS 6 BP 1059 EP 1064 DI 10.2514/2.5374 PG 6 WC Engineering, Aerospace SC Engineering GA 139HK UT WOS:000077022300025 ER PT J AU Rothman, LS Rinsland, CP Goldman, A Massie, ST Edwards, DP Flaud, JM Perrin, A Camy-Peyret, C Dana, V Mandin, JY Schroeder, J McCann, A 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, JY Schroeder, J McCann, A Gamache, RR Wattson, RB Yoshino, K Chance, KV Jucks, KW Brown, LR Nemtchinov, V Varanasi, P TI The HITRAN molecular spectroscopic database and HAWKS (HITRAN Atmospheric Workstation): 1996 edition SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Review ID ABSORPTION CROSS-SECTIONS; COLLISION-INDUCED ABSORPTION; FAR-INFRARED SPECTRUM; SCHUMANN-RUNGE BANDS; NONLOCAL THERMODYNAMIC-EQUILIBRIUM; FOURIER-TRANSFORM SPECTROSCOPY; HIGH-RESOLUTION SPECTROSCOPY; AIR-BROADENING COEFFICIENTS; 720-NM WAVELENGTH REGION; DIODE-LASER SPECTROSCOPY AB Since its first publication in 1973, the HITRAN molecular spectroscopic database has been recognized as the international standard for providing the necessary 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 are forthcoming. Published by Elsevier Science Ltd. C1 VSBM, AF Res Lab, Bedford, MA 01731 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. NASA, Langley Res Ctr, Div Atmospher Sci, Hampton, VA 23681 USA. Univ Denver, Dept Phys, Denver, CO 80208 USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Univ Paris 11, Photophys Mol Lab, CNRS, F-91405 Orsay, France. Univ Paris 06, LPMA, F-75252 Paris 05, France. Ontar Corp, N Andover, MA 01845 USA. Univ Lowell, Dept Environm Earth & Atmospher Sci, Lowell, MA 01854 USA. Utah State Univ, Stewart Radiance Lab, Bedford, MA 01730 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. RP Rothman, LS (reprint author), VSBM, AF Res Lab, 29 Randolph Rd, Bedford, MA 01731 USA. OI Chance, Kelly/0000-0002-7339-7577; Rothman, Laurence/0000-0002-3837-4847 NR 291 TC 1553 Z9 1594 U1 9 U2 81 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD NOV PY 1998 VL 60 IS 5 BP 665 EP 710 DI 10.1016/S0022-4073(98)00078-8 PG 46 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 129YR UT WOS:000076492100002 ER PT J AU Tashkun, SA Perevalov, VI Teffo, JL Rothman, LS Tyuterev, VG AF Tashkun, SA Perevalov, VI Teffo, JL Rothman, LS Tyuterev, VG TI Global fitting of (CO2)-C-12-O-16 vibrational-rotational line positions using the effective Hamiltonian approach SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID CARBON-DIOXIDE BANDS; DIRECT NUMERICAL DIAGONALIZATION; ABSOLUTE INTENSITY MEASUREMENTS; POTENTIAL-ENERGY SURFACE; 5.2 MU-M; MOLECULAR-CONSTANTS; INFRARED-SPECTRUM; 4.5-MU-M REGION; NITROUS-OXIDE; CO2 BANDS AB About 13 000 experimental lines of the principal isotopic species of CO2 selected from the literature have been used to derive about 100 parameters of a reduced effective Hamiltonian built up to sixth order in the Amat-Nielsen ordering scheme. This Hamiltonian has been obtained from an effective Hamiltonian describing all vibrational-rotational energy levels in the ground electronic state and containing in explicit form all resonance interaction terms due to the approximate relations between harmonic frequencies omega(1)approximate to 2 omega(2), and omega(3) approximate to omega(1) + omega(2). An RMS deviation of 0.001 cm(-1) has been achieved in the fitting. In order to test its predictive capabilities, the model has been used to calculate the line positions of six bands: 05511 <-- 05501, 1005(1, 2) <-- 1004(1, 2), 1006(1, 2) <-- 1005(1, 2), and 20033 <-- 00001, which are compared with experimental lines not included in the data set. The results are discussed and compared with the predictions of the Direct Numerical Diagonalization technique. Published by Elsevier Science Ltd. C1 Univ Paris 06, Lab Phys Mol & Applicat, CNRS, F-75252 Paris 05, France. Russian Acad Sci, Inst Atmospher Opt, Tomsk 634055, Russia. VSBM, AF Res Lab, Bedford, MA 01731 USA. Univ Reims, Fac Sci, Grp Spect Mol & Atmospher, F-51687 Reims 2, France. RP Teffo, JL (reprint author), Univ Paris 06, Lab Phys Mol & Applicat, CNRS, Boite 76,4 Pl Jussieu, F-75252 Paris 05, France. RI Tashkun, Sergey/E-8682-2014; OI Rothman, Laurence/0000-0002-3837-4847 NR 54 TC 86 Z9 90 U1 0 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD NOV PY 1998 VL 60 IS 5 BP 785 EP 801 DI 10.1016/S0022-4073(98)00082-X PG 17 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 129YR UT WOS:000076492100006 ER PT J AU Jenkins, CH Marker, DK AF Jenkins, CH Marker, DK TI Surface precision of inflatable membrane reflectors SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB Space-based inflatable technology is of current interest to NASA and DOD, and in particular to the Air Force and Phillips Laboratory. Potentially large gains in lowering launch costs, through reductions in structure mass and volume, are driving this activity. Diverse groups are researching and developing this technology for radio and radar antennae, optical telescopes, and solar power and propulsion applications. Regardless of the use, one common requirement for successful application is the accuracy of the inflated surface shape. The work reported here concerns the shape control of an inflated thin circular disk through use of a nonlinear finite element analysis. First, a review of the important associated Hencky problem is given. Then we discuss a shape modification, achieved through enforced boundary displacements, which resulted in moving the inflated shape towards a desired parabolic profile. Minimization of the figure error is discussed and conclusions are drawn. C1 S Dakota Sch Mines & Technol, Dept Mech Engn, Compliant Struct Lab, Rapid City, SD 57701 USA. USAF, Phillips Lab, Albuquerque, NM 87117 USA. RP Jenkins, CH (reprint author), S Dakota Sch Mines & Technol, Dept Mech Engn, Compliant Struct Lab, Rapid City, SD 57701 USA. NR 39 TC 21 Z9 22 U1 1 U2 5 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD NOV PY 1998 VL 120 IS 4 BP 298 EP 305 DI 10.1115/1.2888134 PG 8 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA 141ND UT WOS:000077149300010 ER PT J AU McIntyre, TC Bowersox, RDW Goss, LP AF McIntyre, TC Bowersox, RDW Goss, LP TI Effects of Mach number on supersonic wraparound fin aerodynamics SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB An experimental Mach number parametric (M is an element of [2.15, 3.83]) study was conducted to investigate the apparent rolling-moment reduction with increasing Mach number noted in flight-test experiments. The aerodynamic loading and the surface flow in the fin region of wraparound fin missiles in high-Reynolds-number (Re-C is an element of 0.3 x 10(6) to 0.9 x 10(6)) supersonic cross streams were investigated using photoluminescent pressure-sensitive paint and surface oil-how visualizations with fluorescent pigment as the seeding medium, Schlieren photography was used to characterize the fin-generated shock structures. Two curved-fin missiles were tested, one having a solid fin and the other a slotted fin. The fin pressures were integrated for rolling moments; these data confirm the solid-fin missile reduction in rolling moment with increasing Mach number. The slotted-fin missile exhibited a similar rolling-moment Mach number dependence, Analysis of the pressure distributions, surface streamlines, and shock structures indicated that the flowfields experienced very strong and complicated inviscid-viscous interactions and that these interactions had a significant impact on the aerodynamic loading of the fins. Finally, the slotted-fin missile demonstrated the potential for increased roll stability and reduced wave drag. C1 USAF, Inst Technol, Launch Programs,Space & Missile Syst Ctr, Medium Launch Vehicle Off Delta 2, Wright Patterson AFB, OH 45433 USA. Univ Alabama, Dept Aerosp Engn & Mech, Tuscaloosa, AL 35487 USA. Innovat Sci Solut Inc, Dayton, OH 45440 USA. RP McIntyre, TC (reprint author), USAF, Inst Technol, Launch Programs,Space & Missile Syst Ctr, Medium Launch Vehicle Off Delta 2, Wright Patterson AFB, OH 45433 USA. NR 11 TC 3 Z9 3 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD NOV-DEC PY 1998 VL 35 IS 6 BP 742 EP 748 DI 10.2514/2.3410 PG 7 WC Engineering, Aerospace SC Engineering GA 156HZ UT WOS:000077996700003 ER PT J AU Reinhardt, KC Mayberry, CS Glaister, DS AF Reinhardt, KC Mayberry, CS Glaister, DS TI Space power technology in power management and distribution electronics SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article AB Significant advancements in the development of lightweight, compact, reliable, and cost-effective electrical power system components are required to enable high-power designs of future generations of satellites. The goal of the U.S. Air Force Phillips Laboratory is to minimize the cost impact of high-power missions by reducing electrical power system mass to 10% of the satellite mass, thereby allowing the use of smaller launch vehicles. By designing payload power converters to operate at higher frequencies and incorporating state-of-the-art packaging techniques, the specific power of payload power converters will reach greater than 100 W/kg and 3 W/cm(3), with substantially increased radiation hardness, Operating these converters at higher input voltage (120 V) will significantly reduce harness mass for higher power missions. This same technology has also benefitted battery charging and discharging units, solar array power regulation devices, and switching and fault protection devices. Finally, high-temperature wide band gap devices were found to reduce the overall satellite mass by eliminating heaters for worst-case cold environment and by reducing the size of radiator components for hot environments. C1 USAF, Res Lab, Power & Thermal Grp, Kirtland AFB, NM 87117 USA. Aerospace Corp, Albuquerque, NM 87119 USA. RP Reinhardt, KC (reprint author), USAF, Res Lab, Power & Thermal Grp, Phillips Res Site, Kirtland AFB, NM 87117 USA. EM reinhark@plk.af.mil; mayberry@plk.af.mil; glaister@kafb.aero.org NR 6 TC 2 Z9 2 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0022-4650 J9 J SPACECRAFT ROCKETS JI J. Spacecr. Rockets PD NOV-DEC PY 1998 VL 35 IS 6 BP 837 EP 844 DI 10.2514/2.3407 PG 8 WC Engineering, Aerospace SC Engineering GA 156HZ UT WOS:000077996700017 ER PT J AU Hassan, W Nagy, PB AF Hassan, W Nagy, PB TI Simplified expressions for the displacements and stresses produced by the Rayleigh wave SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Letter ID RODS AB In many cases involving Rayleigh wave propagation along the free surface of a solid, the ratio between the normal and transverse displacement components, i.e., the aspect ratio of the elliptical particle trajectory on the surface, is of great importance. Surprisingly, this aspect ratio is exactly the same as the ratio between the vector and scalar displacement potential amplitudes. More importantly, the aspect ratio is also identically the same as the ratio between the shear and normal stresses in any plane parallel to the surface at any depth, i.e., exactly the same ratio also shows up between two fundamental physical quantities. It is shown that the identical amplitude ratio, which apparently has not been pointed out in the otherwise very comprehensive literature on Rayleigh wave propagation, is a direct result of the requirement that just below the surface even the oscillating power, i.e., the imaginary component of the Poynting vector, be parallel to the surface (of course, the average power, i.e., the real component of the Poynting vector is everywhere parallel to the surface). (C) 1998 Acoustical Society of America. [S0001-4966(98)06211-0]. C1 Univ Cincinnati, Dept Aerosp Engn & Engn Mech, Cincinnati, OH 45221 USA. RP Hassan, W (reprint author), Wright Lab, Met Ceram & NDE Div, Wright Patterson AFB, Dayton, OH 45432 USA. RI Nagy, Peter/O-5404-2016 OI Nagy, Peter/0000-0001-5715-2409 NR 18 TC 6 Z9 6 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD NOV PY 1998 VL 104 IS 5 BP 3107 EP 3110 DI 10.1121/1.423901 PG 4 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 136RM UT WOS:000076873000059 ER PT J AU Cinibulk, MK AF Cinibulk, MK TI Reactions between hot-pressed calcium hexaluminate and silicon carbide in the presence of oxygen SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID ALUMINOSILICATE GLASSES; OXIDATION-KINETICS; ALUMINA; CERAMICS; DIAGRAMS; NITRIDE AB The reactions between hot-pressed calcium hexaluminate (CaAl12O19, hibonite) and silicon carbide (SiC) at 1100 degrees-1400 degrees C in air and nominal argon atmospheres were investigated. In inert atmospheres, there was no evidence of reaction at temperatures up to at least 1400 degrees C. In air, the oxidation of SIC produced a layer of silica or a multicomponent amorphous silicate (depending on impurities) that reacted with CaAl12O19. At temperatures below 1300 degrees C, the reaction resulted in the stratification of two distinct interfacial layers: a partially devitrified CaO-Al2O3-SiO2 glass adjacent to SiC and a CaAl2Si2O8 (anorthite) layer adjacent to hibonite, At 1400 degrees C, a large amount of liquid was formed, the majority of which was squeezed out from between the reaction couple. No distinct layer of anorthite was present; instead, the anorthite was replaced by a layer of alumina between the glass-rich layer and hibonite, An activation energy of 290 kJ/mol was determined for the reaction, which is consistant with oxygen diffusion through a calcium aluminosilicate glass, The reaction between rare-earth hexaluminates and SiO2 was predicted to produce a more-viscous glass than CaAl12O19 and SiO2 and, therefore, have slower reaction kinetics, because of lower mass transport in the glass. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Cinibulk, MK (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 41 TC 6 Z9 6 U1 0 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD NOV PY 1998 VL 81 IS 11 BP 2789 EP 2798 PG 10 WC Materials Science, Ceramics SC Materials Science GA 137BV UT WOS:000076895000004 ER PT J AU Imbery, TA AF Imbery, TA TI Simplifying dual-arch impressions SO JOURNAL OF THE AMERICAN DENTAL ASSOCIATION LA English DT Article C1 USA Dent Corps, Langley AFB, VA USA. RP Imbery, TA (reprint author), 105 Chestnut Court, Grafton, VA 23692 USA. NR 1 TC 3 Z9 3 U1 0 U2 0 PU AMER DENTAL ASSN PI CHICAGO PA 211 E CHICAGO AVE, CHICAGO, IL 60611 USA SN 0002-8177 J9 J AM DENT ASSOC JI J. Am. Dent. Assoc. PD NOV PY 1998 VL 129 IS 11 BP 1599 EP 1600 PG 2 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 137DC UT WOS:000076898700018 PM 9818578 ER PT J AU Idle, MK Cobb, RG Sullivan, JM Goodding, JC AF Idle, MK Cobb, RG Sullivan, JM Goodding, JC TI Use of a zero-gravity suspension system for testing a vibration isolation system SO JOURNAL OF THE IEST LA English DT Article DE gravity off-load system; vibration isolation; VISS AB The Air Force Research Laboratory team has been confronted with many unique testing challenges in the Ballistic Missile Defense Organization-sponsored Vibration Isolation and Suppression System (VISS) performance test program. VISS incorporates a combination passive/active vibration mitigation technology in a Stewart platform configuration to provide a mechanically quiet platform for a medium-wavelength, infrared camera. VISS actuator stiffnesses, insufficient to support the payload in a 1-g field, require a gravity off-load system to simulate the free boundary conditions of space. A performance test series characterized the test fixture dynamics, VISS payload dynamics, and the open-loop, control system plant. Passive performance has been characterized, and the active performance measured in the laboratory will be verified when VISS is on-orbit. VISS goals include demonstrating good passive-based vibration isolation at high frequencies, augmenting low-frequency isolation with closed-loop control, suppressing an on-board disturbance due to a cryocooler, and demonstrating steering capabilities of the payload with a prescribed amplitude and spectral content. C1 USAF, Res Lab, VISS Program, Albuquerque, NM USA. USAF Acad, Appl Mech Lab, Colorado Springs, CO 80840 USA. CSA Engn Inc, Palo Alto, CA USA. RP Idle, MK (reprint author), USAF, Res Lab, VISS Program, Albuquerque, NM USA. NR 1 TC 0 Z9 0 U1 1 U2 6 PU INST ENVIRONMENTAL SCI TECHNOLOGY PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 USA SN 1052-2883 J9 J IEST JI J. IEST PD NOV-DEC PY 1998 VL 41 IS 6 BP 42 EP 46 PG 5 WC Engineering, Environmental; Environmental Sciences; Instruments & Instrumentation SC Engineering; Environmental Sciences & Ecology; Instruments & Instrumentation GA 151XU UT WOS:000077746600008 ER PT J AU Foltz, TM Welsh, BM AF Foltz, TM Welsh, BM TI Image reconstruction using symmetric convolution and discrete trigonometric transforms SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID COSINE TRANSFORM; SINE AB We demonstrate how the symmetric convolution-multiplication property of the discrete trigonometric transforms can be applied to problems in image reconstruction. This property allows for linear filtering of degraded images by means of point-by-point multiplication in the transform domain of trigonometric transforms. Specifically, in the transform domain of a type II discrete cosine transform, there is an asymptotically optimum energy compaction near d.c. for highly correlated images, which has advantages in reconstructing images with high-frequency noise. The symmetric convolution-multiplication property allows for scalar representations in the transform-domain space of discrete trigonometric transforms for linear reconstruction filters such as the Wiener filter. An analysis of the scalar Wiener filter's performance in the trigonometric transform domain is given. (C) 1998 Optical Society of America. [S0740-3232(98)00511-0]. OCIS codes: 100.0100, 100.1830, 100.2000, 100.2960, 100.2980, 100.3020. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Foltz, TM (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 26 TC 3 Z9 3 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 NOV PY 1998 VL 15 IS 11 BP 2827 EP 2840 DI 10.1364/JOSAA.15.002827 PG 14 WC Optics SC Optics GA 132PL UT WOS:000076638700004 ER PT J AU Ding, Y Nolte, DD Zheng, Z Kanan, A Weiner, AM Brost, GA AF Ding, Y Nolte, DD Zheng, Z Kanan, A Weiner, AM Brost, GA TI Bandwidth study of volume holography in photorefractive InP : Fe for femtosecond pulse readout at 1.5 mu m SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID QUANTUM-WELLS; TRANSFORM CORRELATOR; GAIN ENHANCEMENT; CRYSTAL; RESONANCE; LASER AB The Bragg selectivity of volume holograms makes them not well suited for many Fourier imaging processing applications in the space domain because they perform the function of a spatial filter and limit the field of view. Similarly, for femtosecond pulse holography they reduce the spectral bandwidth of the diffracted signal. However, we show both theoretically and experimentally that it is much easier in the frequency domain than in the space domain to achieve a large enough diffraction bandwidth of volume holograms for the bandwidth of 100-fs pulses to be used for frequency-domain femtosecond pulse shaping. The experiments were performed by nondegenerate four-wave mixing in photorefractive InP:Fe with femtosecond readout at 1.5 mu m. (C) 1998 Optical Society of America [S0740-3224(98)02010-4]. C1 Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Purdue Univ, Sch Elect & Comp Engn, W Lafayette, IN 47907 USA. USAF, Res Lab, SNDR, Rome, NY 13441 USA. RP Ding, Y (reprint author), Purdue Univ, Dept Phys, 1396 Phys Bldg, W Lafayette, IN 47907 USA. RI Zheng, Zheng/D-9726-2012 OI Zheng, Zheng/0000-0001-7661-6846 NR 29 TC 30 Z9 36 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD NOV PY 1998 VL 15 IS 11 BP 2763 EP 2768 DI 10.1364/JOSAB.15.002763 PG 6 WC Optics SC Optics GA 136NF UT WOS:000076865100019 ER PT J AU Hornig, CA AF Hornig, CA TI Consistent results through consistent sampling SO LC GC-MAGAZINE OF SEPARATION SCIENCE LA English DT Letter C1 USAF, Elmendorf AFB, AK 99506 USA. RP Hornig, CA (reprint author), USAF, Elmendorf AFB, AK 99506 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ADVANSTAR COMMUNICATIONS PI DULUTH PA 131 W FIRST ST, DULUTH, MN 55802 USA SN 0888-9090 J9 LC GC-MAG SEP SCI JI LC GC-Mag. Sep. Sci. PD NOV PY 1998 VL 16 IS 11 BP 978 EP 978 PG 1 WC Chemistry, Analytical SC Chemistry GA 139HP UT WOS:000077022700001 ER PT J AU Neale, DH Ellicks, D AF Neale, DH Ellicks, D TI Corrosion protection of munitions using metal arc spray technology SO MATERIALS PERFORMANCE LA English DT Article ID PERFORMANCE; SERVICE AB The design, development, plant integration, and operation of an automated wire arc spray system to implement metallizing technology for corrosion protection of U.S. Ail Force general purpose bombs are described. The zinc/aluminum metallized coating sealed with waterborne acrylic latex direct to metal replaced the original solvent-borne primer-topcoat system to yield an environmentally compliant lifetime corrosion protection coating that eliminates the current requirement for stripping and re-coating munitions every 5 years. Conservative 20-year life cycle analyses predicted substantial cost savings for the Air Force ns well as the achievement of environmental compliance at the Kadena AB Bomb Renovation Plant in Okinawa, Japan. C1 Sci Applicat Int Corp, Marietta, GA 30067 USA. USAF, Corros Program Off, Warner Robins Air Logist Ctr, Warner Robins, GA 31098 USA. RP Neale, DH (reprint author), Sci Applicat Int Corp, 2220 NW Pkwy,Suite 200, Marietta, GA 30067 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0094-1492 J9 MATER PERFORMANCE JI Mater. Perform. PD NOV PY 1998 VL 37 IS 11 BP 32 EP 38 PG 7 WC Materials Science, Characterization & Testing SC Materials Science GA 135YJ UT WOS:000076830200008 ER PT J AU Ash, DL Solomon, CJ Loos, G AF Ash, DL Solomon, CJ Loos, G TI Optimal Hartmann sensing at low light levels SO OPTICS COMMUNICATIONS LA English DT Article ID ATMOSPHERIC-TURBULENCE; ZERNIKE POLYNOMIALS; MODAL COMPENSATION AB A computer model has been used to investigate the performance of a Shack-Hartmann sensor operating under low light level conditions. The trade-off between sub-aperture size and slope noise is examined in detail and optimal sizes are determined for a number of imaging scenarios. Our results are discussed in relation to related literature. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Kent, Sch Phys Sci, Canterbury CT2 7NR, Kent, England. USAF, Res Labs, Kirtland AFB, NM 87117 USA. RP Ash, DL (reprint author), Univ Kent, Sch Phys Sci, Canterbury CT2 7NR, Kent, England. NR 22 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD NOV 1 PY 1998 VL 156 IS 1-3 BP 10 EP 15 DI 10.1016/S0030-4018(98)00398-8 PG 6 WC Optics SC Optics GA 138FH UT WOS:000076960300003 ER PT J AU Tompkins, PK AF Tompkins, PK TI The challenger launch decision: Risky technology, culture, and deviance at NASA SO ORGANIZATION LA English DT Book Review C1 Univ Colorado, Dept Commun, Sch Business, Boulder, CO 80309 USA. USAF Acad, Colorado Springs, CO 80840 USA. RP Tompkins, PK (reprint author), Univ Colorado, Dept Commun, Sch Business, Campus Box 270, Boulder, CO 80309 USA. NR 1 TC 0 Z9 0 U1 1 U2 2 PU SAGE PUBLICATIONS LTD PI LONDON PA 6 BONHILL STREET, LONDON, ENGLAND EC2A 4PU SN 1350-5084 J9 ORGANIZATION JI Organization PD NOV PY 1998 VL 5 IS 4 BP 620 EP 629 DI 10.1177/135050849854010 PG 10 WC Management SC Business & Economics GA 140HC UT WOS:000077081100013 ER PT J AU Tompkins, PK AF Tompkins, PK TI No downlink: A dramatic narrative about the challenger accident and our time SO ORGANIZATION LA English DT Book Review C1 Univ Colorado, Dept Commun, Sch Business, Boulder, CO 80309 USA. USAF Acad, Colorado Springs, CO 80840 USA. RP Tompkins, PK (reprint author), Univ Colorado, Dept Commun, Sch Business, Campus Box 270, Boulder, CO 80309 USA. NR 1 TC 0 Z9 0 U1 1 U2 2 PU SAGE PUBLICATIONS LTD PI LONDON PA 6 BONHILL STREET, LONDON, ENGLAND EC2A 4PU SN 1350-5084 J9 ORGANIZATION JI Organization PD NOV PY 1998 VL 5 IS 4 BP 620 EP 629 DI 10.1177/135050849854010 PG 10 WC Management SC Business & Economics GA 140HC UT WOS:000077081100012 ER PT J AU Ham, BS Shahriar, MS Kim, MK Hemmer, PR AF Ham, BS Shahriar, MS Kim, MK Hemmer, PR TI Spin coherence excitation and rephasing with optically shelved atoms SO PHYSICAL REVIEW B LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; HYPERFINE-STRUCTURE; TRANSITIONS; CRYSTAL; RESONANCE; PULSES; ECHOES AB We investigate the use of resonant optical Raman pulses to excite and rephase ground state spin coherences via the partial storage or shelving of atoms. Unlike direct-rf-excited spin echoes or off-resonant Raman echoes, the resonant Raman optical field efficiently excites and rephases the spin coherence using pi and 2 pi pulses, respectively. In a crystal of Pr3+ doped Y2SiO5, we experimentally observe spin echo efficiency as high as 46% of the free induction decay signal. [S0163-1829(98)50142-7]. C1 MIT, Elect Res Lab, Cambridge, MA 02139 USA. Univ S Florida, Dept Phys, Tampa, FL 33620 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP MIT, Elect Res Lab, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Shahriar, Selim/B-7270-2009; Kim, Myung/L-3575-2014 OI Kim, Myung/0000-0002-2818-8928 NR 20 TC 7 Z9 7 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 1998 VL 58 IS 18 BP R11825 EP R11828 DI 10.1103/PhysRevB.58.R11825 PG 4 WC Physics, Condensed Matter SC Physics GA 141PV UT WOS:000077153400006 ER PT J AU Gavrielides, A Kottos, T Kovanis, V Tsironis, GP AF Gavrielides, A Kottos, T Kovanis, V Tsironis, GP TI Spatiotemporal organization of coupled nonlinear pendula through impurities SO PHYSICAL REVIEW E LA English DT Article ID SYNCHRONIZATION; DISORDER; CHAOS AB We study the effect of impurities introduced into a lattice and their ability to control the dynamical behavior of arrays of coupled nonlinear chaotic oscillators. In particular we show that under certain conditions a single impurity can produce simple spatiotemporal patterns in place of complex chaotic behavior for very long chains of oscillators. Under the same conditions we also examine the effect of disorder in the lengths of the pendula and explain the observed patterns and periodic behavior to be the result of inadvertent impurities. [S1063-651X(98)07311-5]. C1 USAF, Res Lab, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. Weizmann Inst Sci, Dept Phys Complex Syst, IL-76100 Rehovot, Israel. Univ Crete, Dept Phys, Heraklion 71003, Crete, Greece. Fdn Res & Technol Hellas, Heraklion 71003, Crete, Greece. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. RP Gavrielides, A (reprint author), USAF, Res Lab, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. RI Tsironis, George/C-2683-2011 NR 12 TC 37 Z9 39 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD NOV PY 1998 VL 58 IS 5 BP 5529 EP 5534 DI 10.1103/PhysRevE.58.5529 PN A PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 139VU UT WOS:000077052100044 ER PT J AU Rogers, JS Witt, PL Gross, MT Hacke, JD Genova, PA AF Rogers, JS Witt, PL Gross, MT Hacke, JD Genova, PA TI Simultaneous palpation of the craniosacral rate at the head and feet: Intrarater and interrater reliability and rate comparisons SO PHYSICAL THERAPY LA English DT Article DE craniosacral rate; craniosacral therapy ID INTRACLASS CORRELATIONS AB Background and Purpose. The main purpose of this study was to determine the interrater and intrarater reliability of measurements obtained during palpation of the craniosacral rate at the head and feet. Palpated craniosacral rates of head and feet measured simultaneously were also compared, Subjects. Twenty-eight adult subjects and 2 craniosacral examiners participated in the study. Methods. a within-subjects repeated-measures design was used. A standard cubicle privacy curtain, hung over the subject's waist, was used to pr-event the examiners from seeing each other. Results. Interrater intraclass correlation coefficients (ICCs) were .08 at the head and .19 at the feet. Intrarater ICCs ranged from .18 to .30. Craniosacral rates simultaneously palpated at the head and feet were different. Conclusion and Discussion. The results did not support the theories that underlie craniosacral therapy or claims that craniosacral motion can be palpated reliably. C1 USAF Acad, Phys Therapy Clin, Colorado Springs, CO 80840 USA. Univ N Carolina, Div Phys Therapy, Chapel Hill, NC USA. RP Rogers, JS (reprint author), USAF Acad, Phys Therapy Clin, 10 MDGSGPY, Colorado Springs, CO 80840 USA. NR 19 TC 16 Z9 16 U1 0 U2 1 PU AMER PHYSICAL THERAPY ASSOC PI ALEXANDRIA PA 1111 N FAIRFAX ST, ALEXANDRIA, VA 22314 USA SN 0031-9023 J9 PHYS THER JI Phys. Ther. PD NOV PY 1998 VL 78 IS 11 BP 1175 EP 1185 PG 11 WC Orthopedics; Rehabilitation SC Orthopedics; Rehabilitation GA 134WF UT WOS:000076766200003 PM 9806622 ER PT J AU Pessa, JE Zadoo, VP Adrian, EK Yuan, CH Aydelotte, J Garza, JR AF Pessa, JE Zadoo, VP Adrian, EK Yuan, CH Aydelotte, J Garza, JR TI Variability of the midfacial muscles: Analysis of 50 hemifacial cadaver dissections SO PLASTIC AND RECONSTRUCTIVE SURGERY LA English DT Article; Proceedings Paper CT 30th Annual Meeting of the American-Society-for-Aesthetic-Plastic-Surgery CY MAY 02-07, 1997 CL NEW YORK, NEW YORK SP Amer Soc Aesthet Plast Surg ID NASOLABIAL FOLD; SMAS AB The region of the midface represents a challenging area to both reconstructive and aesthetic surgeons.;An anatomic study was performed that attempted to identify patterns and variations of the muscular anatomy. The goals of this study were twofold: to identify patterns and variability of the midfacial muscles that might impact on reconstructive efforts and to attempt to correlate this anatomy with features of the overlying soft tissues, specifically the nasolabial crease. Fifty hemifacial cadaver dissections were performed. The information collected was assembled into a large data base, and statistical significance was analyzed using Fisher's exact probability test. Results demonstrated that, although a great degree of variability exists with respect to the midfacial muscles, seven distinct patterns of these muscles did emerge. The most common pattern was the presence of a levator alae nasi, levator labii superioris, and zygomaticus major, which occurred in 44 percent of specimens. Specimens that possessed a risorius, zygomaticus minor, or both, were relatively uncommon. The consistent presence of the levators suggests adding a superior vector to recreate a smile in facial reanimation surgery. Two important anatomic variations were noted. A bifid zygomaticus major was found to be present in 34 percent of individuals. Because the inferior bundle had a dermocutaneous insertion, this anomaly may represent the anatomic correlate of a cheek "dimple." A second anomaly noted was the lateral check crease, which appeared to be associated with a cutaneous attachment from the underlying platysma muscle. However, no correlation could be found for facial muscle pattern and the overlying nasolabial crease structure. This lack of correlation may indicate that the facial muscles alone do not dictate th; structure of the nasolabial crease and that other dynamic factors are involved in deter mining this feature of the aging face. C1 Univ Texas, Hlth Sci Ctr, Dept Plast Surg, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Struct & Cellular Biol, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Dept Biostat, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Zadoo, VP (reprint author), Univ Texas, Hlth Sci Ctr, Dept Plast Surg, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. NR 17 TC 44 Z9 46 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0032-1052 J9 PLAST RECONSTR SURG JI Plast. Reconstr. Surg. PD NOV PY 1998 VL 102 IS 6 BP 1888 EP 1893 DI 10.1097/00006534-199811000-00013 PG 6 WC Surgery SC Surgery GA 137PK UT WOS:000076924100013 PM 9810983 ER PT J AU Dotrong, M Dotrong, MH Song, HH Santhosh, U Lee, CYC Evers, RC AF Dotrong, M Dotrong, MH Song, HH Santhosh, U Lee, CYC Evers, RC TI Rigid-rod benzobisthiazole polymer with reactive 2,6-dimethylphenoxy pendent groups SO POLYMER LA English DT Article DE rigid-rod polymers; compressive strength; axial registration ID FIBERS AB Polycondensation in polyphosphoric acid of 2,5-diamino-1,4-benzenedithiol dihydrochloride with 2-(2,6-dimethylphenoxy)terephthaloyl chloride led to rigid-rod benzobisthiazole polymers with thermally reactive dimethylphenoxy pendants. Soluble polymers with intrinsic viscosities as high as 15.5 dl/g (methanesulphonic acid, 30 degrees C) were obtained. The polymers became insoluble after heat-treatment at approximately 400 degrees C, possibly indicative of a crosslinking reaction between the polymer chains at the pendant sites. Fibres spun from a lyotropic polyphosphoric acid solution and heat treated at 425 degrees C exhibited a tensile modulus of 91 GPa, a tensile strength of 1.10 GPa, and a compressive strength of 400 MPa. Wide-angle X-ray scattering patterns of the polymer fibres indicated that the bulky pendants significantly enhanced the axial registration between the neighbouring rigid-rod polymer backbones. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. AdTech Syst Res Inc, Dayton, OH 45424 USA. Hannam Univ, Dept Macromol Sci, Taejon, South Korea. Univ Dayton, Res Inst, Nonmet Mat Div, Dayton, OH 45469 USA. RP Evers, RC (reprint author), USAF, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 12 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD NOV PY 1998 VL 39 IS 23 BP 5799 EP 5807 DI 10.1016/S0032-3861(98)00085-8 PG 9 WC Polymer Science SC Polymer Science GA 111LZ UT WOS:000075440000028 ER PT J AU Vaia, RA Dudis, D Henes, J AF Vaia, RA Dudis, D Henes, J TI Chain conformation and flexibility of thorny rod polymers SO POLYMER LA English DT Article DE thorny rod polymers; polyparaphenylenes; chain conformation and flexibility ID MOLECULAR-DYNAMICS SIMULATIONS; REGIOIRREGULAR POLY(P-PHENYLENE)S; SUBSTITUTED HYDROQUINONES; THERMOPLASTIC POLYIMIDE; COMPUTER-SIMULATION; AMORPHOUS STARCH; SIDE-CHAINS; POLYPHENYLENES; WATER; POLY(PARA-PHENYLENE)S AB Molecular dynamics simulations and rotational isomeric state (RIS) theory are used to systematically examine the effect of the regioregularity of monomer linkages and the size of the pendant on the rotational barriers, flexibility and chain conformation of substituted polyparaphenylenes including hydrogen, methyl, tert-butyl, phenyl, methoyl and benzoyl pendants (R=H, CH3, C(CH3)(3), C6H5, COCH3, and COC6H5, respectively). The influence of the substituents on chain structure and properties can be broadly distinguished based on the degree of cooperativity for rotation about the paraphenylene linkage necessitated by the steric demands of the pendant. For some substituents (R=C6H5, COCH3, and COC6H5), backbone and pendant motion are intimately coupled leading to thorny rod polymers. In general, the conformation of these polymers depends on the relative ratio of regiospecific linkages and on the distortions of the backbone bond angles necessary to accommodate the pendants. For example, the persistence length of the chain decreases by almost an order-of-magnitude when the ortho-hydrogen of paraphenylene is replaced by a benzoyl pendant. Furthermore, chain flexibility is restricted to specific regioregular linkages and dynamic distortions of the backbone phenyl linkages. The relatively large intramolecular barriers to rotational motion will result in long relaxation times, frustrating chain packing and potentially leading to kinetically limited metastable states in the solid and melt. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP Vaia, RA (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 48 TC 11 Z9 11 U1 0 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD NOV PY 1998 VL 39 IS 24 BP 6021 EP 6036 DI 10.1016/S0032-3861(98)00113-X PG 16 WC Polymer Science SC Polymer Science GA 114UJ UT WOS:000075627300017 ER PT J AU Haverluk, TW AF Haverluk, TW TI Hispanic community types and assimilation in Mex-America SO PROFESSIONAL GEOGRAPHER LA English DT Article DE assimilation; Hispanic; community type; Mex-America ID SPATIAL ASSIMILATION; MEXICAN AB I argue that discrepancies among Hispanic assimilation models can be interpreted through three distinct types of Hispanic communities-continuous, discontinuous, and new Continuous communities were founded by Hispanics and Hispanics have always been the majority population. As a result, Hispanics have not assimilated as predicted by traditional models. Discontinuous communities were originally serried by Hispanics, but eventually were filled by a minority population. Since WWII, many of these communities have experienced a Hispanic demographic resurgence making assimilation more problematic. Hispanics in new communities are recent immigrants to Angle dominant communities and are more apr to follow the traditional assimilation model. C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Haverluk, TW (reprint author), USAF Acad, 2354 Fairchild Dr,Suite 6K12, Colorado Springs, CO 80840 USA. NR 43 TC 14 Z9 14 U1 0 U2 0 PU BLACKWELL PUBLISHERS PI MALDEN PA 350 MAIN STREET, STE 6, MALDEN, MA 02148 USA SN 0033-0124 J9 PROF GEOGR JI Prof. Geogr. PD NOV PY 1998 VL 50 IS 4 BP 465 EP 480 DI 10.1111/0033-0124.00133 PG 16 WC Geography SC Geography GA 216MK UT WOS:000081446300005 ER PT J AU Frei, MR Jauchem, JR Dusch, SJ Merritt, JH Berger, RE Stedham, MA AF Frei, MR Jauchem, JR Dusch, SJ Merritt, JH Berger, RE Stedham, MA TI Chronic, low-level (1.0 W/kg) exposure of mice prone to mammary cancer to 2450 MHz microwaves SO RADIATION RESEARCH LA English DT Article ID RADIOFREQUENCY RADIATION; ELECTROMAGNETIC-FIELDS; LONG-TERM; TUMORS; RATS AB In a previous study (Frei et al., Bioelectromagnetics 19, 20-31, 1998), we showed that low-level (0.3 W/kg), long-term exposure of mice prone to mammary tumors to 2450 MHz radiofrequency (RF) radiation did not affect the incidence of mammary tumors, latency to tumor onset, tumor growth rate or animal survival when compared to sham-irradiated animals. In the current study, the specific absorption rate (SAR) was increased from 0.3 W/kg to 1.0 W/kg. The same biological end points were used. One hundred C3H/HeJ mice were exposed in circularly polarized waveguides for 78 weeks (20 h/day, 7 days/week) to continuous-wave, 2450 MHz RF radiation; 100 mice were sham-exposed. There was no significant difference between exposed and sham-exposed groups with respect to the incidence of palpated mammary tumors (sham-exposed = 30%; irradiated = 38%), latency to tumor onset (sham-exposed = 62.0 +/- 2.3 weeks; irradiated = 62.5 +/- 2.2 weeks) and rate of tumor growth. Histopathological evaluations revealed no significant difference in numbers of malignant, metastatic or benign neoplasms between the two groups. Thus long-term exposures of mice prone to mammary tumors to 2450 MHz RF radiation at SARs of 0.3 and 1.0 W/kg had no significant effects when compared to sham-irradiated animals. (C) 1998 by Radiation Research Society. C1 USAF, Res Lab,Radio Frequency Radiat Branch, Directed Energy Bioeffects Div, Human Effect Directorate, Brooks AFB, TX 78235 USA. Trinity Univ, Dept Biol, San Antonio, TX 78284 USA. Operat Technol Corp, San Antonio, TX 78284 USA. Pathol Associates Int, Frederick, MD 21701 USA. RP Jauchem, JR (reprint author), USAF, Res Lab,Radio Frequency Radiat Branch, Directed Energy Bioeffects Div, Human Effect Directorate, Armstrong Res Site, Brooks AFB, TX 78235 USA. NR 29 TC 31 Z9 35 U1 0 U2 1 PU RADIATION RESEARCH SOC PI LAWRENCE PA 810 E TENTH STREET, LAWRENCE, KS 66044 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD NOV PY 1998 VL 150 IS 5 BP 568 EP 576 DI 10.2307/3579874 PG 9 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 164ZN UT WOS:000078493600010 PM 9806599 ER PT J AU Valladares, CE Fukui, K Sheehan, R Carlson, HC Bullett, T AF Valladares, CE Fukui, K Sheehan, R Carlson, HC Bullett, T TI Simultaneous observations of polar cap patches and Sun-aligned arcs during transitions of the IMF SO RADIO SCIENCE LA English DT Article; Proceedings Paper CT HLPS/GAPS Peaceful Valley III Workshop CY JUN 15-17, 1997 CL LYONS, COLORADO SP Natl Sci Fdn, CEDAR Program, Utah State Univ, Ctr Atmospher & Space Sci ID F-LAYER PATCHES; MAGNETIC-FIELD; CONVECTION; REGION; TIME; MAGNETOPAUSE; IONOSPHERE; DIRECTION; DYNAMICS; PATTERN AB This paper presents the first observations of simultaneous polar cap patches and polar cap arcs in a single common 1000-km field of view, and identifies a model that explains the interplanetary magnetic field (IMF) dependencies of the observed phenomenology. To study the characteristics of the polar cap optical emissions in the 630.0 nm line during transitions of the IMF B-z, we have scanned images taken at Qaanaaq, Greeland, between 1989 and 1994. We found that on a few occasions, when B-z changed from a south to a north orientation, a particular pattern of polar cap patches and Sun-aligned arcs coexisted. No similar pattern of coexisting arcs and patches was found during north-to-south IMF transitions. The detailed analyses of three of these events are presented here in which patches and polar cap arcs are clearly identified to reside simultaneously within the Qaanaaq imager field of view. The digisonde located also at Qaanaaq is used to confirm that the optical patches correspond to enhancements in the number density and a simultaneous decrease of the h(m)F(2) value. These two factors increase the capability of the imager to differentiate between patches and the background airglow. Data collected by the DMSP F8 satellite during one of the events reaffirm the appearance of polar cap precipitation during the B-z positive period. The J4 sensor on board DMSP F8 detected typical electron fluxes commonly associated with polar cap arcs. The coexistence of patches and arcs is due to a slower response of the patches in exiting the polar cap, and then the relatively sudden appearance of polar cap arcs presumably driven by dayside reconnection between the IMF and open flux drawn initially equatorward toward the cusp. This model, of dayside reconnection switching from equatorward of the cusp for B-z south to poleward of the cusp for B-z north, likewise explains why arcs and patches are seen by the imager to coexist for rapid B-z reversals only from south to north and not from north to south. C1 Boston Coll, Inst Sci Res, Chestnut Hill, MA 02167 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Valladares, CE (reprint author), Boston Coll, Inst Sci Res, Chestnut Hill, MA 02167 USA. NR 27 TC 3 Z9 3 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD NOV-DEC PY 1998 VL 33 IS 6 BP 1829 EP 1845 DI 10.1029/98RS02187 PG 17 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 145HR UT WOS:000077365500027 ER PT J AU Pedersen, TR Fejer, BG Doe, RA Weber, EJ AF Pedersen, TR Fejer, BG Doe, RA Weber, EJ TI Incoherent scatter radar observations of horizontal F region plasma structure over Sondrestrom, Greenland, during polar cap patch events SO RADIO SCIENCE LA English DT Article; Proceedings Paper CT HLPS/GAPS Peaceful Valley III Workshop CY JUN 15-17, 1997 CL LYONS, COLORADO SP Natl Sci Fdn, CEDAR Program, Utah State Univ, Ctr Atmospher & Space Sci ID ELECTRON-DENSITY PATCHES; LAYER PATCHES; MAGNETOSPHERIC CONVECTION; IONIZATION PATCHES; IONOSPHERE; IDENTIFICATION; IRREGULARITIES; DYNAMICS; ORIGIN AB Horizontal profiles of F region plasma density from the Sondrestrom incoherent scatter radar facility (66.99 degrees N latitude, 50.95 degrees W longitude) are used to determine the large-scale structure and statistical distribution of ionospheric plasma during polar cap patch events. Large-scale latitudinal gradients in average electron density were observed coincident with primarily meridional flow, suggesting the plasma decayed with time constants of the order of 1 hour. Plasma density distributions for each of the five nights in the data set were characterized by peaks at low plasma densities representing the background plasma, with the presence of patches typically resulting in a "tail" in the high-density regime of the distribution. Observed patch sizes averaged similar to 400 km, with a most probable value in the 200- to 300-km range. Patch edges were found to be characterized by gradient scale lengths of similar to 100 km, significantly smaller than the typical 400-km scale length of background gradients. Gradients interior to patches were intermediate in magnitude, with average scale lengths of similar to 275 lan. The general characteristics of the patches in these data, including their occurrence in latitude and local time, are consistent with an origin in a tongue of ionization. The observed distributions of patch scale sizes and density enhancement ratios verify the general features of earlier results from satellite measurements. The relatively short decay time constants inferred from this data set suggest that patches do not survive long enough to make multiple passes through the convection pattern and that their impact as a source of auroral zone blobs may be mostly limited to the nightside ionosphere. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. SRI Int, Radio Sci & Engn Div, Menlo Park, CA 94025 USA. Utah State Univ, Ctr Atmospher & Space Sci, Logan, UT 84322 USA. RP Pedersen, TR (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 35 TC 17 Z9 17 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD NOV-DEC PY 1998 VL 33 IS 6 BP 1847 EP 1866 DI 10.1029/98RS01702 PG 20 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 145HR UT WOS:000077365500028 ER PT J AU Basu, S Weber, EJ Bullett, TW Keskinen, MJ MacKenzie, E Doherty, P Sheehan, R Kuenzler, H Ning, P Bongiolatti, J AF Basu, S Weber, EJ Bullett, TW Keskinen, MJ MacKenzie, E Doherty, P Sheehan, R Kuenzler, H Ning, P Bongiolatti, J TI Characteristics of plasma structuring in the cusp/cleft region at Svalbard SO RADIO SCIENCE LA English DT Article; Proceedings Paper CT HLPS/GAPS Peaceful Valley III Workshop CY JUN 15-17, 1997 CL LYONS, CO SP Natl Sci Fdn, CEDAR Program, Utah State Univ, Ctr Atmospher & Space Sci ID F-LAYER PATCHES; POLAR-CAP; PHASE FLUCTUATIONS; AURORAL OVAL; LOW-ALTITUDE; CUSP; IONOSPHERE; IRREGULARITIES; DYNAMICS; SCINTILLATION AB Satellite scintillation, all-sky optical imager, and digisonde observations were coordinated during a cusp campaign conducted at Ny Alesund, Svalbard (78.9 degrees N, 11.8 degrees E; 75.7 degrees N corrected geomagnetic latitude, over the period January 4-15, 1997. This paper is focused on a study of the distribution and dynamics of mesoscale (tens of kilometers to tens of meters) electron density irregularities in the dayside auroral region. This study has been performed at Ny Alesund, Svalbard, by measuring the effects of these irregularities on the amplitude scintillation of 250-MHz transmissions from a quasi-stationary polar satellite as well as the amplitude and phase scintillation of 1.6-GHz signals from Global Positioning System (GPS) satellites. These GPS scintillation measurements were augmented by the use of dual-frequency (1.2 and 1.6 GHz) GPS phase data acquired at the same station by the Jet Propulsion Laboratory for the International GPS Geodynamic Service (IGS). The continuous 250-MHz scintillation observations explored the daytime auroral ionosphere 2 degrees poleward of Ny Alesund and showed that the scintillation spectra are often broad, as may be expected for irregularities in a turbulent flow region. Such irregularity dynamics were detected poleward of the nominal cusp region over the interval of 0600-1500 magnetic local time. The period of observations included the magnetic storm of January 10-11, 1997, when GPS observations of the IGS detected polar cap patches with total electron contents of 3 x 10(16) m(-2) and large-scale (tens of kilometers) phase variations at the GPS frequency of 1.6 GHz that corresponded to temporal gradients of 2 x 10(16) m(-2) min(-1). However, amplitude scintillations at the GPS frequency of 1.6 GHz could not be detected in association with these large-scale phase variations, indicating that the irregularities with wavelengths less than the Fresnel dimension of 400 m were below the detectable limit. This is shown to be consistent in the context of enhanced ionospheric convection determined by digisonde and scintillation spectra. C1 USAF, Res Lab, AFRL, VSBI, Hanscom AFB, MA 01731 USA. Boston Coll, Inst Sci Res, Newton, MA 02159 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. KEO Consultants, Brookline, MA 02146 USA. RP USAF, Res Lab, AFRL, VSBI, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. EM santimay@aol.com; webere@plh.af.mil; bullett@plh.af.mil; keskinen@ppd.nrl.navy.mil NR 32 TC 51 Z9 51 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 EI 1944-799X J9 RADIO SCI JI Radio Sci. PD NOV-DEC PY 1998 VL 33 IS 6 BP 1885 EP 1899 DI 10.1029/98RS01597 PG 15 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 145HR UT WOS:000077365500031 ER PT J AU Guzdar, PN Gondarenko, NA Chaturvedi, PK Basu, S AF Guzdar, PN Gondarenko, NA Chaturvedi, PK Basu, S TI Three-dimensional nonlinear simulations of the gradient drift instability in the high-latitude ionosphere SO RADIO SCIENCE LA English DT Article; Proceedings Paper CT HLPS/GAPS Peaceful Valley III Workshop CY JUN 15-17, 1997 CL LYONS, COLORADO SP Natl Sci Fdn, CEDAR Program, Utah State Univ, Ctr Atmospher & Space Sci ID POLAR-CAP; DENSITY STRUCTURES; VELOCITY SHEAR; PATCHES AB Nonlinear three-dimensional (3-D) simulations of the gradient drift instability (GDI) are presented for a two-dimensional equilibrium density gradient representing a polar cap plasma patch. The overall evolution of structuring of the plasma patch is influenced markedly by the effects caused by dynamics parallel to the geomagnetic field. The long wavelengths (kL(n)less than or equal to 1) are strongly stabilized in the 3-D case, and the nonlinear state is dominated by smaller mesoscales (kL(n)much greater than 1) (where k and L-n are the, mode number and density gradient scale length, respectively). The results provide an interpretation to the observations at the high-latitude ionosphere indicating a generation of mesoscale irregularities associated with the polar cap patches when the interplanetary magnetic field (IMF) B-z is southward and antisunward convection prevails over the polar cap. The polar cap patches are observed to convect to large:distances (similar to 3000 km) undergoing structuring while maintaining their distinct identity. Thus we suggest here that the inclusion of three-dimensional effects is key to a successful interpretation of high-latitude irregularities, as well as a prerequisite for a credible simulation of these processes. C1 Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. USAF, Res Lab, Hanscom, MA 01731 USA. RP Guzdar, PN (reprint author), Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. NR 14 TC 17 Z9 17 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD NOV-DEC PY 1998 VL 33 IS 6 BP 1901 EP 1913 DI 10.1029/98RS01703 PG 13 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 145HR UT WOS:000077365500032 ER PT J AU Anwar, AFM Webster, RT AF Anwar, AFM Webster, RT TI Energy bandgap of AlxGa1-xAs1-ySby and conduction band discontinuity of AlxGa1-xAs1-ySby/InAs and AlxGa1-xAs1-ySby/InGaAs heterostructures SO SOLID-STATE ELECTRONICS LA English DT Letter ID ALGAASSB AB A technique to determine the conduction band discontinuity in any heterostructure and the resulting band alignment is presented. Energy bandgaps of the quaternary AlGaAsSb and conduction band discontinuity for lattice matched AlxGa1-xAs1-ySby/InAs, AlxGa1-xAs1-ySby/In0.8Ga0.2As and AlxGa1-xAs1-ySby/In0.52Ga0.48As heterostructures are reported for varying Al and Sb mole fractions to demonstrate the method. AlxGa1-xAs1-ySby/InAs changes from a type-II broken-gap alignment to type-ii staggered alignment near an Al mole fraction of 0.15 followed by a change from type II to type-I near an Al mole fraction of 0.9. No type-II broken-band alignments are observed in the other two lattice matched systems. The minimum Al mole fraction required for type-I band alignment increases with increasing In mole fraction. It is shown that the quaternary bandgap becomes indirect for Al mole fractions greater than approximately 0.4 and the conduction band discontinuity is a linear function of the Al mole fraction for the lattice-matched systems. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Connecticut, Dept Elect & Syst Engn, Storrs, CT 06269 USA. USAF, Res Lab, Div Electromagnet Technol, Sensors Directorate, Hanscom AFB, MA 01731 USA. RP Anwar, AFM (reprint author), Univ Connecticut, Dept Elect & Syst Engn, Storrs, CT 06269 USA. NR 11 TC 16 Z9 16 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD NOV PY 1998 VL 42 IS 11 BP 2101 EP 2104 DI 10.1016/S0038-1101(98)00157-9 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 138WC UT WOS:000076995500031 ER PT J AU Newton, HN Barnhart, C Vance, PH AF Newton, HN Barnhart, C Vance, PH TI Constructing railroad blocking plans to minimize handling costs SO TRANSPORTATION SCIENCE LA English DT Article ID NETWORK DESIGN; TRANSPORTATION; ALGORITHMS; MODELS AB On major domestic railroads, a typical general merchandise shipment may pass through many classification yards on its route from origin to destination. At these yards, the incoming traffic, which may consist of a number of individual shipments, is reclassified (sorted and grouped together) to be placed on outgoing trains. Each reclassification incurs costs due to handling and delay. To prevent shipments from being reclassified at every yard they pass through, several shipments may be grouped together to form a block. A block has associated with an origin-destination pair that may or may not be the origin or destination of any of the individual cars contained in the block. The objective of the railroad blocking problem is to choose which blocks to build at each yard and to assign sequences of blocks to deliver each shipment to minimize total mileage, handling, and delay costs. We model the railroad blocking problem as a network design problem in which yards are represented by nodes and blocks by arcs. Our model is intended as a strategic decision-making tool. We develop a column generation, branch-and-bound algorithm in which attractive paths for each shipment are generated by solving a shortest path problem. Our solution approach is unique in constraining the classification resources of each yard and simultaneously solving for different priority classes of shipments. We implement our algorithm and find near-optimal solutions in about one hour for the blocking problem of a large domestic railroad, in which the paths that shipments may take in the physical network are restricted The resulting network design problem has 150 nodes, 1300 commodities, and 6800 possible arcs (blocks). We test the robustness of our solution on 19 test instances that are variations of the data for the real-world problems. If shipments are restricted to following one of a limited number of paths in the rail network, then, in four hours or less, our algorithm finds solutions within 0.4% of optimal for all test cases. Furthermore, the solutions obtained are no more than 3.9% from optimal even if all possible paths are allowed. C1 USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. MIT, Dept Civil & Environm Engn, Cambridge, MA 02139 USA. Emory Univ, Goizueta Business Sch, Atlanta, GA 30322 USA. RP Newton, HN (reprint author), USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. NR 21 TC 47 Z9 51 U1 1 U2 2 PU OPERATIONS RESEARCH SOC AMER PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2920 USA SN 0041-1655 J9 TRANSPORT SCI JI Transp. Sci. PD NOV PY 1998 VL 32 IS 4 BP 330 EP 345 DI 10.1287/trsc.32.4.330 PG 16 WC Operations Research & Management Science; Transportation; Transportation Science & Technology SC Operations Research & Management Science; Transportation GA 141KD UT WOS:000077142100002 ER PT J AU Dawson, DL Beebe, HG Davidson, MH Chinoy, DA Herd, JA Hiatt, WR Heckman, JD Bortey, EB Forbes, WP AF Dawson, DL Beebe, HG Davidson, MH Chinoy, DA Herd, JA Hiatt, WR Heckman, JD Bortey, EB Forbes, WP TI Cilostazol or pentoxifylline for claudication? SO CIRCULATION LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Jobst Vasc Ctr, Toledo, OH USA. Chicago Ctr Clin Res, Chicago, IL USA. Jacksonville CV Ctr, Jacksonville, FL USA. Baylor Coll Med, Houston, TX 77030 USA. Univ Colorado, Denver, CO 80202 USA. Otsuka Amer Pharmaceut Inc, Rockville, MD USA. NR 0 TC 6 Z9 6 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 27 PY 1998 VL 98 IS 17 SU S MA 58 BP 12 EP 12 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 131UV UT WOS:000076594400107 ER PT J AU Downs, JR Clearfield, M Weis, S Whitney, EJ Shapiro, DR Beere, PA Gotto, AM AF Downs, JR Clearfield, M Weis, S Whitney, EJ Shapiro, DR Beere, PA Gotto, AM TI Air Force Texas Coronary Atherosclerosis Prevention Study: Primary prevention of coronary heart disease in women SO CIRCULATION LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Univ N Texas, HSC, Ft Worth, TX USA. Heart & Vasc Inst Texas, San Antonio, TX USA. Merck & Co Inc, W Point, PA USA. Cornell Univ, New York, NY USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 27 PY 1998 VL 98 IS 17 SU S MA 225 BP 46 EP 46 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 131UV UT WOS:000076594400273 ER PT J AU Whitney, EJ Downs, JR Clearfield, M Weis, S Stein, EA Shapiro, DR Beere, PA Gotto, AM AF Whitney, EJ Downs, JR Clearfield, M Weis, S Stein, EA Shapiro, DR Beere, PA Gotto, AM TI Air Force Texas Coronary Atherosclerosis Prevention Study: Extending the benefit of primary prevention to healthy elderly men and women SO CIRCULATION LA English DT Meeting Abstract C1 Heart & Vasc Inst Texas, San Antonio, TX USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Univ N Texas, HSC, Ft Worth, TX USA. MARC, Highland Heights, KY USA. Merck & Co Inc, W Point, PA USA. Cornell Univ, New York, NY USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 27 PY 1998 VL 98 IS 17 SU S MA 226 BP 46 EP 46 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 131UV UT WOS:000076594400274 ER PT J AU Personius, BE Brown, BG Gotto, A Little, OM AF Personius, BE Brown, BG Gotto, A Little, OM TI Effects of increasing HDL-C, lowering triglyceride and lowering LDL-C on "fixed" atherosclerotic coronary artery disease. AFREGS (The Armed Forces Regression Study). SO CIRCULATION LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Univ Washington, Seattle, WA 98195 USA. Cornell Univ, New York, NY USA. OML Associates, Dripping Spring, TX USA. Heart & Vasc Inst Texas, San Antonio, TX USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 27 PY 1998 VL 98 IS 17 SU S MA 2369 BP 450 EP 451 PG 2 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 131UV UT WOS:000076594402394 ER PT J AU Steckl, AJ Garter, M Birkhahn, R Scofield, J AF Steckl, AJ Garter, M Birkhahn, R Scofield, J TI Green electroluminescence from Er-doped GaN Schottky barrier diodes SO APPLIED PHYSICS LETTERS LA English DT Article ID ERBIUM; LUMINESCENCE; SILICON; SEMICONDUCTORS; EPITAXY AB Visible light electroluminescence (EL) has been obtained from Er-doped GaN Schottky barrier diodes. The GaN was grown by molecular beam epitaxy on Si substrates using solid sources (for Ga, and Er) and a plasma source for N-2. Al was utilized for both the Schottky (small-area) and ground (large-area) electrodes. Strong green light emission was observed under reverse bias, with weaker emission present under forward bias. The emission spectrum consists of two narrow green lines at 537 and 558 nm and minor peaks at 413 and at 666/672 nm. The green emission lines have been identified as Er transitions from the H-2(11/12) and S-4(3/2) levels to the I-4(15/2) ground state and the blue and red peaks as the H-2(9/2) and F-4(9/2) Er transitions to the same ground state. The reverse bias EL intensity was found to increase linearly with bias current. (C) 1998 American Institute of Physics. [S0003-6951(98)00343-X]. C1 Univ Cincinnati, Nanoelect Lab, Cincinnati, OH 45221 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Steckl, AJ (reprint author), Univ Cincinnati, Nanoelect Lab, Cincinnati, OH 45221 USA. OI Steckl, Andrew/0000-0002-1868-4442 NR 17 TC 82 Z9 83 U1 2 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 26 PY 1998 VL 73 IS 17 BP 2450 EP 2452 DI 10.1063/1.122478 PG 3 WC Physics, Applied SC Physics GA 129LN UT WOS:000076465200020 ER PT J AU Turk, W AF Turk, W TI Antarctic airlift recalled SO AVIATION WEEK & SPACE TECHNOLOGY LA English DT Letter C1 USAF, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MCGRAW HILL INC PI NEW YORK PA 1221 AVENUE OF THE AMERICAS, NEW YORK, NY 10020 USA SN 0005-2175 J9 AVIAT WEEK SPACE TEC JI Aviat. Week Space Technol. PD OCT 26 PY 1998 VL 149 IS 17 BP 6 EP 6 PG 1 WC Engineering, Aerospace SC Engineering GA 132DB UT WOS:000076614000005 ER PT J AU Moinpour, CM Savage, MJ Troxel, A Lovato, LC Eisenberger, M Veith, RW Higgins, B Skeel, R Yee, M Blumenstein, BA Crawford, ED Meyskens, FL AF Moinpour, CM Savage, MJ Troxel, A Lovato, LC Eisenberger, M Veith, RW Higgins, B Skeel, R Yee, M Blumenstein, BA Crawford, ED Meyskens, FL TI Quality of life in advanced prostate cancer: Results of a randomized therapeutic trial SO JOURNAL OF THE NATIONAL CANCER INSTITUTE LA English DT Article ID HEALTH SURVEY SF-36; INTERMITTENT ANDROGEN SUPPRESSION; OF-LIFE; CLINICAL-TRIALS; NORMAL MEN; FLUTAMIDE; ONCOLOGY; ANTIANDROGEN; TESTOSTERONE; RELIABILITY AB Background: For patients with metastatic prostate cancer, treatment is primarily palliative, relying mainly on the suppression of systemic androgen hormone levels. To help document the achievement of palliation and to characterize positive and negative effects of treatment, we evaluated quality-of-life (QOL) parameters in patients with metastatic prostate cancer who were randomly assigned to two methods of androgen deprivation. Methods: Patients (n = 739) with stage M-1 (bone or soft tissue metastasis) prostate cancer were enrolled in a QOL protocol that was a companion to Southwest Oncology Group INT-0105, a randomized double-blind trial comparing treatment with bilateral orchiectomy (surgical castration) plus either flutamide or placebo. Patients completed a comprehensive battery of QOL questionnaires at random assignment to treatment and at 1, 3, and 6 months later. Data were collected on three treatment-specific symptoms (diarrhea, gas pain, and body image), on physical functioning, and on emotional functioning. All P values are two-sided. Results: Questionnaire return rates for this study never dropped below 80%; only 2% of the patients did not submit baseline QOL assessments. Cross-sectional analyses (corrected for multiple testing) identified statistically significant differences that favored orchiectomy plus placebo for two of the five primary QOL parameters as follows: patients receiving flutamide reported more diarrhea at 3 months (P =.001) and worse emotional functioning at 3 and 6 months (both P<.003), Longitudinal analyses replicated these findings. Other analyzed QOL parameters favored the group receiving placebo but were not statistically significant after adjustment for multiple testing. Conclusions: We found a consistent pattern of better QOL outcomes at each follow-up assessment during the first 6 months of treatment for orchiectomized patients with metastatic prostate cancer who received placebo versus flutamide, Improvement over time was evident in both treatment groups but more so for patients receiving placebo. C1 Fred Hutchinson Canc Res Ctr, SW Oncol Grp S9039, Ctr Stat, Operat Off, San Antonio, TX 78245 USA. Mercy Med Ctr, Baltimore, MD USA. Columbia Presbyterian Canc Ctr, New York, NY USA. Johns Hopkins Univ, Sch Med, Baltimore, MD USA. Louisiana State Univ, Med Ctr, New Orleans, LA USA. Wilford Hall USAF Med Ctr, Brooke Army Med Ctr, San Antonio, TX USA. Med Coll Ohio, Toledo, OH 43699 USA. Univ Colorado, Denver, CO 80202 USA. Univ Calif Irvine, Chao Family Comprehens Canc Ctr, Irvine, CA 92717 USA. RP Moinpour, CM (reprint author), Fred Hutchinson Canc Res Ctr, SW Oncol Grp S9039, Ctr Stat, Operat Off, 14980 Omicron Dr, San Antonio, TX 78245 USA. FU NCI NIH HHS [CA13612, CA37429, CA37981] NR 51 TC 91 Z9 94 U1 0 U2 4 PU NATL CANCER INSTITUTE PI BETHESDA PA 9030 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0027-8874 J9 J NATL CANCER I JI J. Natl. Cancer Inst. PD OCT 21 PY 1998 VL 90 IS 20 BP 1537 EP 1544 DI 10.1093/jnci/90.20.1537 PG 8 WC Oncology SC Oncology GA 131KN UT WOS:000076575300012 PM 9790546 ER PT J AU Ryan, PT Fugate, RQ Angel, JRP McCarthy, DW Mohanty, S Sandler, DG AF Ryan, PT Fugate, RQ Angel, JRP McCarthy, DW Mohanty, S Sandler, DG TI Halo characteristics and their influence on companion searches at the Starfire Optical Range SO APPLIED OPTICS LA English DT Article ID ADAPTIVE OPTICS; EXTRASOLAR PLANETS; PERFORMANCE; RESOLUTION; TELESCOPES AB To image extrasolar planets at their large contrast, high-resolution adaptive optics (AO) is needed to correct atmospheric seeing. The 1.5-m AO system at the Starfire Optical Range was used to confirm theoretical models. Halo levels were reduced by a factor of 4, on average, from 0.5 to 3.0 arc sec radius, which when combined with the increased Strehl ratio improved the gain by a factor of 80. Speckle lifetimes ranged from 5 to 30 ms at 0.3 are sec, which is much longer than the 0.6-ms AO update time. These results show good agreement with predictions for current technology and reveal no limitations, in principle, to the detection of planets by use of AO systems with higher speeds and resolutions. (C) 1998 Optical Society of America. C1 USAF, Phillips Lab, Starfire Opt Range, Kirtland AFB, NM 87117 USA. Univ Arizona, Steward Observ, Ctr Astron Adapt Opt, Tucson, AZ 85721 USA. ThermoTrex Corp, San Diego, CA 92121 USA. RP Ryan, PT (reprint author), USAF, Phillips Lab, Starfire Opt Range, Kirtland AFB, NM 87117 USA. NR 26 TC 4 Z9 4 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD OCT 20 PY 1998 VL 37 IS 30 BP 7035 EP 7043 DI 10.1364/AO.37.007035 PG 9 WC Optics SC Optics GA 130ZE UT WOS:000076549900004 PM 18301521 ER PT J AU Venner, MJ Bruce, CW AF Venner, MJ Bruce, CW TI Absorption cross section of moderately conducting disks at 35 GHz SO APPLIED OPTICS LA English DT Article ID SCATTERING AB Absorption cross-sectional measurements and model predictions of 25 disks with moderate electrical conductivity were made. The disk radii span part of the resonance region, and their thicknesses are an order of magnitude less than the skin depth. A photoacoustic apparatus, with a 35-GHz microwave source, was used to measure the absorption cross sections. The disks tend to be more absorbing when they are edge-on rather than broadside to the incident microwaves. Also they absorb most efficiently near a size parameter of 1. Model predictions generally agree with the measured magnitudes and trends in the data. (C) 1998 Optical Society of America. C1 USAF, Res Lab, Propuls Sci Div, Edwards AFB, CA 93524 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. RP Venner, MJ (reprint author), USAF, Res Lab, Propuls Sci Div, 10 E Saturn Blvd, Edwards AFB, CA 93524 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD OCT 20 PY 1998 VL 37 IS 30 BP 7143 EP 7150 DI 10.1364/AO.37.007143 PG 8 WC Optics SC Optics GA 130ZE UT WOS:000076549900023 PM 18301540 ER PT J AU Michalek, JE Ketchum, NS Akhtar, FZ AF Michalek, JE Ketchum, NS Akhtar, FZ TI Postservice mortality of US Air Force veterans occupationally exposed to herbicides in Vietnam: 15-year follow-up SO AMERICAN JOURNAL OF EPIDEMIOLOGY LA English DT Article DE dioxins; herbicides; mortality ID OPERATION RANCH HAND; SERUM DIOXIN; PROPORTIONATE MORTALITY; CANCER MORTALITY; HEALTH-STATUS; WORKERS; COHORT; GONADOTROPINS; TESTOSTERONE; EXPERIENCE AB The US Air Force continues to assess the mortality of veterans of Operation Ranch Hand, the unit responsible for aerially spraying herbicides in Vietnam. The authors of this study found that the cumulative all-cause mortality experience of these veterans was not different from that expected (standardized mortality ratio (SMR) = 1.0). Overall, cause-specific mortality did not differ from that expected regarding deaths from accidents, cancer, or circulatory system diseases, but the authors found that there was an increased number of deaths due to digestive diseases (SMR = 1.7, 95% confidence interval (CI) 0.9-3.2). When analyzing by military occupation, they found an increase in the number of deaths caused by circulatory system diseases (SMR = 1.5, 95% CI 1.0-2.2) among enlisted ground personnel, the subgroup with the highest dioxin levels. Most of the increase in the number of deaths from digestive diseases was caused by chronic liver disease and cirrhosis, and more than half of the increase in the number of deaths from circulatory system diseases was a result of atherosclerotic heart disease. In the subgroup of Ranch Hand veterans who had survived more than 20 years since their military service in Southeast Asia, the authors found no significant increase in the risk of death due to cancer at all sites (SMR = 1.1) and a nonsignificant increase in the number of deaths due to cancers of the bronchus and lung (SMR = 1.3). C1 USAF, Res Lab, HEDB, Brooks AFB, TX 78235 USA. Vista Technol, San Antonio, TX USA. RP Michalek, JE (reprint author), USAF, Res Lab, HEDB, 2606 Doolittle Rd,Bldg 807, Brooks AFB, TX 78235 USA. NR 25 TC 37 Z9 37 U1 1 U2 2 PU JOHNS HOPKINS UNIV SCHOOL HYGIENE PUB HEALTH PI BALTIMORE PA 111 MARKET PLACE, STE 840, BALTIMORE, MD 21202-6709 USA SN 0002-9262 J9 AM J EPIDEMIOL JI Am. J. Epidemiol. PD OCT 15 PY 1998 VL 148 IS 8 BP 786 EP 792 PG 7 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 128VW UT WOS:000076429900009 PM 9786233 ER PT J AU Carlson, JL AF Carlson, JL TI The fearless flier's handbook: The internationally recognized method for overcoming the fear of flying. SO LIBRARY JOURNAL LA English DT Book Review C1 Vandenberg AF Base Lib, Vandenberg AFB, CA 93437 USA. RP Carlson, JL (reprint author), Vandenberg AF Base Lib, Vandenberg AFB, CA 93437 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD OCT 15 PY 1998 VL 123 IS 17 BP 88 EP 88 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 128JX UT WOS:000076403600156 ER PT J AU Hohl, A Gavrielides, A AF Hohl, A Gavrielides, A TI Experimental control of a chaotic semiconductor laser SO OPTICS LETTERS LA English DT Article ID EXTERNAL OPTICAL FEEDBACK; DIODE-LASERS; STABILITY AB We have experimentally controlled the chaotic output of a single-mode semiconductor laser pumped near threshold and subject to optical feedback. We used a novel technique called dynamic targeting, which was theoretically proposed by Wieland et al. [Opt. Lett. 22, 469 (1997)]. Optical feedback causes the semiconductor laser to undergo a bifurcation cascade that exhibits regions of stability, periodicity, chaos, and coherence collapse. By adjusting the feedback phase simultaneously as the feedback strength was varied we steered the laser into the stable maximum gain mode, and thus we stabilized the system at maximum intensity. (C) 1998 Optical Society of America. C1 USAF, Res Lab DELO, Nonlinear Opt Grp, Kirtland AFB, NM 87117 USA. RP Hohl, A (reprint author), USAF, Res Lab DELO, Nonlinear Opt Grp, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 13 TC 11 Z9 12 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD OCT 15 PY 1998 VL 23 IS 20 BP 1606 EP 1608 DI 10.1364/OL.23.001606 PG 3 WC Optics SC Optics GA 131NU UT WOS:000076582800014 PM 18091859 ER PT J AU Liebst, BS AF Liebst, BS TI The dynamics, prediction, and control of wing rock in high-performance aircraft SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE wing rock; aircraft dynamics; aircraft controls; nonlinear dynamics; flight mechanics; aircraft stability and control AB This study is an investigation of the nonlinear aircraft behaviour known as wing rock. An eight-state F-15 model is analysed by using bifurcation theory and root-locus techniques. The wing-rock onset point is identified, and small perturbation analysis is used to linearize the equations of motion about this point. The eigenstructure of the model is analysed and is used to identify the stability modes involved in this motion. A procedure is developed to predict wing-rock onset, and the critical stability derivatives involved in this behaviour are identified. The developed procedure is applied to existing F-15 data. The results show that wing rock is an unstable Dutch-roll motion and the developed wing-rock prediction parameter is accurate to within 1 degrees of onset angle of attack (AOA). Various simple feedback control schemes are evaluated to determine how to delay the onset of wing rock. The most effective control scheme is found to be a combination of roll rate and sideslip fixed gain feedback to the ailerons yielding a 6 degrees improvement in the onset AOA of wing rock. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Liebst, BS (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 22 TC 7 Z9 8 U1 1 U2 7 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X J9 PHILOS T R SOC A JI Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci. PD OCT 15 PY 1998 VL 356 IS 1745 BP 2257 EP 2276 DI 10.1098/rsta.1998.0273 PG 20 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 136DT UT WOS:000076843800007 ER PT J AU Habib, YM Oates, DE Dresselhaus, G Dresselhaus, MS Vale, LR Ono, RH AF Habib, YM Oates, DE Dresselhaus, G Dresselhaus, MS Vale, LR Ono, RH TI Microwave power handling in engineered YBa2Cu3O7-delta grain boundaries SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; SUPERCONDUCTORS AB Microwave-frequency (rf) power-dependence measurements performed on thin-film YBa2Cu3O7-delta grain boundaries engineered on sapphire bicrystal substrates with misorientation angles of theta=2 degrees, 5 degrees, 10 degrees, and 24 degrees are presented. The data are compared to measurements on films grown on single-crystal substrates. A stripline-resonator measurement technique is employed. The rf results are compared to dc measurements performed on a four-point test structure on the same substrate as the resonator. The measurements demonstrate that low-angle grain boundaries (theta less than or equal to 10 degrees) have little effect on the rf power handling, while the high-angle grain boundaries (theta=24 degrees) cause large nonlinear losses due to Josephson vortices created by rf currents. (C) 1998 American Institute of Physics. [S0003-6951(98)04541-0]. C1 MIT, Dept Phys, Cambridge, MA 02139 USA. Natl Inst Stand & Technol, Boulder, CO 80303 USA. Lincoln Lab, Lexington, MA 02420 USA. USAF, Res Lab, Bedford, MA 01731 USA. RP Habib, YM (reprint author), MIT, Dept Phys, Cambridge, MA 02139 USA. EM habib@ll.mit.edu NR 14 TC 15 Z9 15 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 12 PY 1998 VL 73 IS 15 BP 2200 EP 2202 DI 10.1063/1.122422 PG 3 WC Physics, Applied SC Physics GA 128UX UT WOS:000076427700045 ER PT J AU Eisenberger, MA Blumenstein, BA Crawford, ED Miller, G McLeod, DG Loehrer, PJ Wilding, G Sears, K Culkin, DJ Thompson, IM Bueschen, AJ Lowe, BA AF Eisenberger, MA Blumenstein, BA Crawford, ED Miller, G McLeod, DG Loehrer, PJ Wilding, G Sears, K Culkin, DJ Thompson, IM Bueschen, AJ Lowe, BA TI Bilateral orchiectomy with or without flutamide for metastatic prostate cancer SO NEW ENGLAND JOURNAL OF MEDICINE LA English DT Article ID PHASE-III; PROGNOSTIC FACTORS; CLINICAL-TRIAL; CARCINOMA; DIETHYLSTILBESTROL; CASTRATION; NILUTAMIDE; THERAPY; ACETATE AB Background Combined androgen blockade for the treatment of metastatic prostate cancer consists of an antiandrogen drug plus castration. In a previous trial, we found that adding the antiandrogen flutamide to leuprolide acetate (a synthetic gonadotropin-releasing hormone that results in medical ablation of testicular function) significantly improved survival as compared with that achieved with placebo plus leuprolide acetate. In the current trial, we compared flutamide plus bilateral orchiectomy with placebo plus orchiectomy. Methods We randomly assigned patients who had never received antiandrogen therapy and who had distant metastases from adenocarcinoma of the prostate to treatment with bilateral orchiectomy and either flutamide or placebo. Patients were stratified according to the extent of disease and according to performance status. Results Of the 1387 patients who were enrolled in the trial, 700 were randomly assigned to the flutamide group and 687 to the placebo group. Overall, the incidence of toxic effects was minimal; the only notable differences between the groups were the greater rates of diarrhea and anemia with flutamide. There was no significant difference between the two groups in overall survival (P=0.14). The estimated risk of death (hazard ratio) for flutamide as compared with placebo was 0.91 (90 percent confidence interval, 0.81 to 1.01). Flutamide was not associated with enhanced benefit in patients with minimal disease. Conclusions The addition of flutamide to bilateral orchiectomy does not result in a clinically meaningful improvement in survival among patients with metastatic prostate cancer. (N Engl J Med 1998;339: 1036-42.) (C) 1998, Massachusetts Medical Society. C1 SW Oncol Grp SWOG 8894, Operat Off, Ctr Stat, San Antonio, TX 78245 USA. Johns Hopkins Hosp, Baltimore, MD 21287 USA. Univ Colorado, Denver, CO 80202 USA. Walter Reed Army Med Ctr, Washington, DC 20307 USA. Indiana Univ, Med Ctr, Indianapolis, IN USA. Univ Wisconsin, Ctr Clin Canc, Madison, WI USA. Univ Oklahoma, Hlth Sci Ctr, Oklahoma City, OK USA. Brooke Army Med Ctr, Wilford Hall USAF Med Ctr, San Antonio, TX USA. Oregon Hlth Sci Univ, Portland, OR 97201 USA. RP Eisenberger, MA (reprint author), SW Oncol Grp SWOG 8894, Operat Off, Ctr Stat, 14980 Omicron Dr, San Antonio, TX 78245 USA. FU NCI NIH HHS [CA32102, CA42777, CA38926] NR 25 TC 558 Z9 576 U1 2 U2 13 PU MASS MEDICAL SOC PI BOSTON PA 10 SHATTUCK, BOSTON, MA 02115 USA SN 0028-4793 J9 NEW ENGL J MED JI N. Engl. J. Med. PD OCT 8 PY 1998 VL 339 IS 15 BP 1036 EP 1042 DI 10.1056/NEJM199810083391504 PG 7 WC Medicine, General & Internal SC General & Internal Medicine GA 126LL UT WOS:000076294800004 PM 9761805 ER PT J AU Curliss, DB Cowans, BA Caruthers, JM AF Curliss, DB Cowans, BA Caruthers, JM TI Cure reaction pathways of bismaleimide polymers: A solid-state N-15 NMR investigation SO MACROMOLECULES LA English DT Article ID CURING KINETICS; POLYIMIDES; BEHAVIOR; RESINS; C-13 AB The cure reaction pathways of a bismaleimide resin with a diamine are investigated using solid-state N-15 NMR spectroscopic techniques with specifically labeled monomers. These techniques provide clear identification of at least three different reaction pathways in the curing resin, one of which has previously been only postulated. In the homopolymerized bismaleimide resin system, maleimide ring addition has previously been shown to be the only observable reaction. When co-reacted with an amine, Michael addition of the amine to the maleimide ring has also been observed. Furthermore, a ring-opening aminolysis reaction, which has been observed in solution with specific reagents and conditions, has been suggested to occur under cure conditions. We show conclusively that this aminolysis reaction occurs to a significant extent during the cure of the neat resin and that this product can remain in the network structure even after a high-temperature postcure treatment. The existence of the amide product is demonstrated using bismaleimide resin formulations selectively labeled with C-13 and N-15 at specific sites. The N-15 chemical shifts and the C-13-N-15 scalar couplings are consistent with and confirm the amide product formation. Furthermore, under certain cure and postcure conditions, the aminolysis reaction is reversible which may significantly affect the final network structure. C1 USAF, Res Lab, MLBC, Wright Patterson AFB, OH 45433 USA. Purdue Univ, Sch Chem Engn, W Lafayette, IN 47907 USA. RP Curliss, DB (reprint author), USAF, Res Lab, MLBC, Wright Patterson AFB, OH 45433 USA. NR 25 TC 29 Z9 31 U1 1 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 6 PY 1998 VL 31 IS 20 BP 6776 EP 6782 DI 10.1021/ma9718255 PG 7 WC Polymer Science SC Polymer Science GA 128DE UT WOS:000076389300006 ER EF