FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Carmack, DB Kaylor, KL Yaszemski, MJ AF Carmack, DB Kaylor, KL Yaszemski, MJ TI Structural stiffness and reducibility of external fixators placed in malalignment and malrotation SO JOURNAL OF ORTHOPAEDIC TRAUMA LA English DT Article DE external fixator; tibia fracture ID COMPARATIVE BIOMECHANICAL EVALUATION; FIXATION FRAME AB Objective: To determine the structural stiffness and reducibility of various external fixators placed in malalignment and malrotation. Design: Uniform testing of all external fixator configurations. Setting: Orthopaedic biomechanical laboratory. Methods: Thirteen external fixators from different manufacturers, in a total of fifteen configurations, were studied. All external fixators were applied to a malreduction jig initially, and a subsequent anatomic reduction was then attempted. If an anatomic reduction was possible, the structural stiffness of those fixators was determined. If anatomic reduction was not possible, the external fixator was removed and reapplied to an anatomically reduced model, and then structural stiffness was determined. Results: Six of the thirteen external fixator configurations allowed an anatomic reduction after placement on a malreduction model. The other nine external fixator configurations would not allow for an anatomic reduction. All the external fixator configurations were biomechanically tested in anteroposterior bending, lateral bending, axial load, and torsion. Each fixator had its own structural stiffness and is reported. Conclusions: Some external fixators will not allow for an anatomic reduction once placed in malalignment and malrotation without repositioning of the fixator pins. External fixator configurations (i.e., single-pin, dual-pin, and multipin barclamps) affect structural stiffness. Structural stiffness widely varied among the external fixators. Propel external fixator selection will enable early fracture immobilization in malalignment and malrotation in suboptimal conditions (e.g., wartime conditions or a civilian disaster), with subsequent external fixator adjustment for an anatomic reduction. C1 Wilford Hall USAF Med Ctr, Dept Orthopaed Surg, Lackland AFB, TX 78236 USA. Duluth Clin, Dept Orthopaed Surg, Duluth, MN USA. Mayo Clin, Dept Orthopaed Surg, Rochester, MN USA. Mayo Med Sch, Dept Orthopaed Surg, Rochester, MN USA. RP Carmack, DB (reprint author), Wilford Hall USAF Med Ctr, Dept Orthopaed Surg, Lackland AFB, TX 78236 USA. NR 23 TC 2 Z9 2 U1 1 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0890-5339 J9 J ORTHOP TRAUMA JI J. Orthop. Trauma PD MAY PY 2001 VL 15 IS 4 BP 247 EP 253 DI 10.1097/00005131-200105000-00003 PG 7 WC Orthopedics; Sport Sciences SC Orthopedics; Sport Sciences GA 434JV UT WOS:000168812100003 PM 11371789 ER PT J AU Manke, GC Hager, GD AF Manke, GC Hager, GD TI A review of recent experiments and calculations relevant to the kinetics of the HF laser SO JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA LA English DT Review DE energy transfer; fluorine atom recombination; HF kinetics; HF laser modeling; molecular relaxation; rotational nonequilibrium ID DOUBLE-RESONANCE MEASUREMENTS; ROTATIONAL ENERGY-TRANSFER; HIGHLY EXCITED DIATOMICS; VIBRATIONAL-RELAXATION; MOLECULAR-BEAM; ATMOSPHERIC CHEMISTRY; IUPAC SUBCOMMITTEE; CROSS-SECTIONS; EINSTEIN COEFFICIENTS; PHOTOCHEMICAL DATA AB A review of rate coefficients relevant to HF laser kinetics modeling is presented. The literature has been surveyed from the last published review in 1983 to the present. Updated HF Einstein emission coefficients are tabulated. Rate coefficients are categorized according to their role in the HF laser model: HF generation, reactive quenching, self-relaxation, V-V energy transfer, vibrational relaxation by atoms and molecules, F-2 dissociation, and F atom recombination. In addition, a review of recent experiments and theoretical calculations relevant to the role of rotational nonequilibrium in HF lasers is presented. A list of recommended temperature dependent expressions for critical reaction rate coefficients is given. (C) 2001 American Institute of Physics. C1 Air Force Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Manke, GC (reprint author), Air Force Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 141 TC 24 Z9 26 U1 3 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0047-2689 J9 J PHYS CHEM REF DATA JI J. Phys. Chem. Ref. Data PD MAY-JUN PY 2001 VL 30 IS 3 BP 713 EP 733 DI 10.1063/1.1376723 PG 21 WC Chemistry, Multidisciplinary; Chemistry, Physical; Physics, Multidisciplinary SC Chemistry; Physics GA 475AG UT WOS:000171139000002 ER PT J AU Gaitonde, DV Visbal, MR Shang, JS Zheltovodov, AA Maksimov, AI AF Gaitonde, DV Visbal, MR Shang, JS Zheltovodov, AA Maksimov, AI TI Sidewall interaction in an asymmetric simulated scramjet inlet configuration SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID TURBULENT INTERACTION; FIN; FLOWS AB The complex three-dimensional flowfield arising from the interaction of a shock-induced turbulent vortical structure with a sidewall boundary layer is examined by numerically solving the Reynolds-averaged compressible Navier-Stokes equations closed with a two-equation k-epsilon turbulence model. The configuration considered is representative of a scramjet inlet compression system and comprises two opposed sharp fins mounted on a Rat plate at 7 and 15 deg to the incoming Row. The flowfield arising from the impingement of a primary vortical structure on the 7 deg fin is found to be strongly dependent on the state of the boundary layer on this sidewall, An elegant turbulent kinetic energy production-limiting technique is employed to reproduce the complicated saddle-spiral topology observed in the experimental sidewall oil Row pattern. Detailed analysis of the computed flow field shows that the main consequence of the interaction is characterized by the ejection of the vortex formed at the fin-plate junction (corner vortex in the terminology of single-fin Rows) in a direction along the sidewall and normal to the plate. The flowfield asymptotes to the classic two-dimensional shock-turbulent boundary-layer interaction at large distances from the plate. C1 USAF, Res Lab, Air Vehicle Directorate, VAAC, Wright Patterson AFB, OH 45433 USA. Russian Acad Sci, Inst Theoret & Appl Mech, Novosibirsk 630090, Russia. RP Gaitonde, DV (reprint author), USAF, Res Lab, Air Vehicle Directorate, VAAC, Bldg 146,Room 225,2210 8th St, Wright Patterson AFB, OH 45433 USA. NR 24 TC 5 Z9 5 U1 4 U2 6 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 MAY-JUN PY 2001 VL 17 IS 3 BP 579 EP 584 DI 10.2514/2.5780 PG 6 WC Engineering, Aerospace SC Engineering GA 434FN UT WOS:000168804600013 ER PT J AU Ashgriz, N Brocklehurst, W Talley, D AF Ashgriz, N Brocklehurst, W Talley, D TI Mixing mechanisms in a pair of impinging jets SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID ATOMIZATION CHARACTERISTICS; WATER JETS AB An experimental investigation of mixing in impinging jet atomizers is conducted. Both miscible and immiscible liquid jets are tested. In the miscible liquid jet experiments, two water jets are impacted on each other. One of the jets is colored and traced across the spray. The liquid is sampled at different locations in the spray using a linear patternator. The volume fraction of each jet in the sampled volume is determined through the measurement of the color intensity. In the immiscible liquid jet experiments, a water-kerosene combination is used. The local volume fractions are determined by direct measurement of the volume of each component in the sampled volume. The volume fraction profiles are used to characterize the mixing processes and determine the quality (or extent) of mixing in such atomizers, Results show that two distinct processes control mixing: 1) the ability of the two jets to redirect each other on impact and before atomization (preatomization process) and 2) the turbulent dispersion in the spray region (postatomization process). The preatomization process can result in two types of atomizations: reflective and transmitive atomization, In the reflective atomization, the jets basically bounce on of each other, causing the fluid of each jet to remain on the same side of the jet. In the transmitive atomization, the direction of the momentum does not change completely, and the fluid of each jet Rows to the side of the other jet. The results show that in this type of atomization, the higher the jet momentum in the plane of jet centerlines, the higher the degree of stream crossing and, therefore, the lower the extent of mixing. The directional momentum increases by increasing jet velocity and diameter and the impingement angle. On the other hand, the turbulent dispersion in the postatomization region improves the mixing. Consequently, the extent of mixing increases downstream of the impingement point. C1 SUNY Buffalo, Dept Mech & Aerosp Engn, Buffalo, NY 14260 USA. SPARTA Inc, El Segundo, CA 90245 USA. USAF, Res Lab, Propuls Directorate, Edwards AFB, CA 93524 USA. RP Ashgriz, N (reprint author), SUNY Buffalo, Dept Mech & Aerosp Engn, Buffalo, NY 14260 USA. NR 38 TC 19 Z9 19 U1 1 U2 13 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 MAY-JUN PY 2001 VL 17 IS 3 BP 736 EP 749 DI 10.2514/2.5803 PG 14 WC Engineering, Aerospace SC Engineering GA 434FN UT WOS:000168804600034 ER PT J AU Miller, HC McCord, JE Choy, J Hager, GD AF Miller, HC McCord, JE Choy, J Hager, GD TI Measurement of the radiative lifetime of O-2(a(1)Delta(g)) using cavity ring down spectroscopy SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE cavity ring down spectroscopy; singlet delta oxygen; COIL ID ABSORPTION-MEASUREMENTS; DOWN SPECTROSCOPY; OXYGEN; LASER; TRANSITION; LINES AB Cavity ring down spectroscopy has been used to detect the weak a(1)Delta (g) - X(3)Sigma (-)(g) electronic transition in oxygen and to obtain a measurement of the radiative lifetime of the a(1)Delta (g) state. (0,0) band transitions near 1274 nm were scanned using the frequency-doubled output of a tunable OPO system. Pressure-broadened linewidths were measured, and a FWHM-broadening coefficient of 5.5(5) MHz/Torr was obtained. Analysis of the ring down traces provided a measurement of the line strength of an individual rovibronic transition. The Einstein A-coefficient of the a(1)Delta (g) state was calculated using branching ratios determined from the Honl-London factors. The A-coefficient obtained is 2.3(3) x 10(-4) s(-1), corresponding to a radiative lifetime of 4300(500) s ( similar to 72 min). This value is in agreement with those reported by Badger et al. (2.58 x 10(-4) s(-1)) and Spalek et al, (2.24(40) x 10(-4) s(-1)). In addition, a value of 2.77(8) x 10(-45) cm(5)/molecule was obtained for the background collisional absorption coefficient for oxygen at 1274 nm. Published by Elsevier Science Ltd. C1 USAF, Res Lab, AFMC, Dept Air Force, Kirtland AFB, NM 87117 USA. RP USAF, Res Lab, AFMC, Dept Air Force, Bldg 619,Room 1,3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. EM john.mccord@kirtland.af.mil NR 38 TC 39 Z9 40 U1 1 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 EI 1879-1352 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD MAY 1 PY 2001 VL 69 IS 3 BP 305 EP 325 DI 10.1016/S0022-4073(00)00086-8 PG 21 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 414ZU UT WOS:000167696700004 ER PT J AU Wise, JO Smith, DR Wheeler, NB Ahmadjian, M Nadile, RM Sullivan, BF AF Wise, JO Smith, DR Wheeler, NB Ahmadjian, M Nadile, RM Sullivan, BF TI Overview and summary of results and significant findings from the CIRRIS-1A experiment SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Review ID INFRARED RADIANCE INSTRUMENTATION; SPACE-SHUTTLE EXPERIMENT; NIGHTTIME TERRESTRIAL THERMOSPHERE; ATMOSPHERIC LIFETIME EXPERIMENT; LIMB SPECTRAL MEASUREMENTS; ROTATIONALLY EXCITED NO+; NITRIC-OXIDE; EMISSION-SPECTRA; OPTICAL CONTAMINATION; MIDDLE ATMOSPHERE AB The cryogenic infrared radiance instrumentation for shuttle (CIRRIS) experiment was flown onboard STS-39 from 29 April to 1 May 1991. A comprehensive set of spectral and spatial infrared data of atmospheric and Earth terrain data was collected by an interferometer and radiometer. The mission occurred during a major geomagnetic storm (K-P greater than or equal to 5) and as a result, a substantial amount of spectral data on bright auroral backgrounds were collected in the midnight sector of the auroral oval. The coincidental timing of the CIRRIS mission, only a few weeks before the eruption of Mount Pinatubo (June 1991.), substantially increased the value of the stratospheric data from CIRRIS, which now serves as a clean atmosphere baseline against which various post-Pinatubo observations can be compared to assess the short- and long-term effects of a major volcanic eruption on the stratosphere. In addition, there were a number of unexpected and important scientific discoveries that resulted from analysis of the CIRRIS high-resolution Earthlimb emission spectra including the identification of an important new class of non-local thermodynamic equilibrium emissions resulting from highly rotationally excited diatomic species (OH, NO and NO+) in the mesosphere and thermosphere. These nonthermal rotational emissions were observed for both day and nighttime conditions and were not included in or predicted by existing atmospheric models before the CIRRIS Eight. A brief overview of the instrumentation and data collection methods is presented. A general review of the CIRRIS data and a summary of the most significant findings previously reported by various groups are also presented. C1 USAF, Res Lab, Space Vehicles Directorate, VSBP,Space Phys Models Branch, Hanscom AFB, MA 01731 USA. USAF, Res Lab, Space Vehicles Directorate, VSBP,Backgrounds Characterizat Branch, Hanscom AFB, MA 01731 USA. USAF, Res Lab, Inst Sci Res, Hanscom AFB, MA 01731 USA. Boston Coll, Chestnut Hill, MA 02467 USA. RP Wise, JO (reprint author), USAF, Res Lab, Space Vehicles Directorate, VSBP,Space Phys Models Branch, Hanscom AFB, MA 01731 USA. NR 125 TC 5 Z9 7 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 MAY-JUN PY 2001 VL 38 IS 3 BP 297 EP 322 DI 10.2514/2.3694 PG 26 WC Engineering, Aerospace SC Engineering GA 442XF UT WOS:000169309700001 ER PT J AU Ketsdever, AD AF Ketsdever, AD TI Design considerations for cryogenic pumping arrays in spacecraft-thruster interaction facilities SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AIAA 38th Aerospace Sciences Meeting and Exhibit CY JAN 10-15, 2000 CL RENO, NEVADA SP Amer Inst Aeronatu & Astronaut AB In general, the simulation of the space environment in ground-based facilities poses many challenges, and the study of propulsion-system-induced effects on spacecraft poses additional challenges to a facility's design due to the complex nature of thruster flows. Low facility background pressures at high mass flow rates are required to obtain meaningful interaction data. Although there is some history to draw from for the design of space simulation chambers, there are very few design philosophies for thruster-spacecraft interaction facilities. This study explores some of the more interesting design philosophies for spacecraft-thruster interaction facilities and offers general guidelines for future designs. C1 USAF, Res Lab, Adv Concept & Prop Sci Div, Prop Directorate, Edwards AFB, CA 93524 USA. RP Ketsdever, AD (reprint author), USAF, Res Lab, Adv Concept & Prop Sci Div, Prop Directorate, 10 E Satum Blvd, Edwards AFB, CA 93524 USA. NR 32 TC 6 Z9 6 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 MAY-JUN PY 2001 VL 38 IS 3 BP 400 EP 410 DI 10.2514/2.3698 PG 11 WC Engineering, Aerospace SC Engineering GA 442XF UT WOS:000169309700013 ER PT J AU Brungart, DS AF Brungart, DS TI Evaluation of speech intelligibility with the coordinate response measure SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The sentences in the coordinate response measure (CRM) corpus described in a recent letter to this journal [Bolia er al., J. Acoust. Sec. Am. 107, 1065-1066 (2000)] have been used to measure speech intelligibility as a function of signal-to-noise ratio with a speech-spectrum-shaped noise masker. The data from this experiment, along with those of an earlier experiment comparing intelligibility with the CRM and the well-known modified rhyme test (MRT), have also been used to estimate performance with the CRM as a function of the articulation index (AI) for a variety of different masking signals. The results provide a normative evaluation of the CRM for potential users of the CRM corpus, and can be used to compare the CRM with other measures of speech intelligibility. C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Brungart, DS (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. NR 5 TC 34 Z9 36 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 2001 VL 109 IS 5 BP 2276 EP 2279 DI 10.1121/1.1357812 PN 1 PG 4 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 431AC UT WOS:000168608700053 PM 11386582 ER PT J AU Hagino, RT Rossi, PJ Rossi, MB Valentine, RJ Clagett, GP AF Hagino, RT Rossi, PJ Rossi, MB Valentine, RJ Clagett, GP TI Asymptomatic carotid stenosis and unrelated operations: Should we be more aggressive? SO JOURNAL OF THE AMERICAN COLLEGE OF SURGEONS LA English DT Article ID STROKE; RISK; ENDARTERECTOMY; DISEASE; SURGERY; ARTERY AB BACKGROUND: Carotid lesions will often remain asymptomatic during the perioperative period, so prophylactic carotid endarterectomy (CEA) has not been advocated before other operations. The purpose of this study was to characterize the clinical manifestations of new neurologic symptoms occurring in patients with previously asymptomatic carotid occlusive disease who have undergone recent operations. STUDY DESIGN: We performed a retrospective review of patients developing neurologic symptoms attributable to carotid occlusive disease after unrelated operations. RESULTS: Eleven patients (mean age 68 +/- 6.4 years, 8 men, 3 women) developed new neurologic symptoms from previously asymptomatic extracranial carotid stenoses after 11 unrelated procedures. Neurologic events included hemispheric stroke (n = 10) and amaurosis fugax (n = 1). Two intraoperative strokes occurred (one mastectomy, one prostatectomy). Other events occurred a mean of 5.8 +/- 5 (range 1 to 16) days after aortic surgery (n = 2), infrainguinal bypass (n = 3), contralateral CEA for symptomatic disease (n = 2), incisional herniorrhaphy (n = 1), and prostate surgery (n = 1). Responsible internal carotid artery lesions were all stenoses greater than 80%; seven were dearly greater than 90%. Those suffering intraoperative stroke or stroke within 24 hours of operation (n = 3) were not receiving antithrombotic therapy. All other events (n = 8) occurred despite the use of antiplatelet or anticoagulant agents. Four underwent emergent CEA. Four had elective CEA performed after reaching a neurological recovery plateau. CONCLUSIONS: Critical, asymptomatic internal carotid artery stenoses may cause neurologic symptoms after unrelated surgical procedures. (J Am Coll Surg 2001;192:608-613. (C) 2001 by the American College of Surgeons). C1 Univ Texas, SW Med Ctr, Div Vasc Surg, Dallas, TX 75390 USA. Midwestern Vasc Inst, Hopeland, IL USA. Wilford Hall USAF Med Ctr, Vasc Surg Sect, Lackland AFB, TX 78236 USA. RP Clagett, GP (reprint author), Univ Texas, SW Med Ctr, Div Vasc Surg, 5323 Harry Hines Blvd, Dallas, TX 75390 USA. NR 17 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1072-7515 J9 J AM COLL SURGEONS JI J. Am. Coll. Surg. PD MAY PY 2001 VL 192 IS 5 BP 608 EP 613 DI 10.1016/S1072-7515(01)00848-1 PG 6 WC Surgery SC Surgery GA 425MM UT WOS:000168294600010 PM 11333098 ER PT J AU Liou, JJ Huang, CI AF Liou, JJ Huang, CI TI AlGaAs/GaAs heterojunction bipolar transistors for power applications: issues of thermal effect and reliability SO MICROELECTRONICS JOURNAL LA English DT Article; Proceedings Paper CT 5th International Seminar on Power Semiconductors CY AUG 31-SEP 02, 2000 CL PRAGUE, CZECH REPUBLIC DE heterojunction bipolar transistor; thermal effect; semiconductor ID HBTS AB AlGaAs/GaAs heterojunction bipolar transistor (HBT) has the advantages of superior switching speed, wide linearity, and high current handling capability. As a result, the device has gained popularity in designing power amplifiers for RF and microwave applications. However, the high power in the HBT, together with the poor thermal conductivity of GaAs, gives rise to significant thermal effect and reduced reliability in such a device. This paper presents an overview on the simulation, modeling, and reliability of AlGaAs/GaAs HBTs. Emphasis will be placed on the effects of thermal-electrical interacting behavior on the de and ac performance of the HBT. The thermal-induced degradation process in the HBT will also be addressed and analyzed. (C) 2001 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Cent Florida, Sch Elect Engn & Comp Sci, Orlando, FL 32816 USA. USAF, Res Lab, Wright Lab, Wright Patterson AFB, OH 45433 USA. RP Liou, JJ (reprint author), Univ Cent Florida, Sch Elect Engn & Comp Sci, Orlando, FL 32816 USA. NR 20 TC 1 Z9 2 U1 0 U2 0 PU ELSEVIER ADVANCED TECHNOLOGY PI OXFORD PA OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0026-2692 J9 MICROELECTR J JI Microelectron. J. PD MAY-JUN PY 2001 VL 32 IS 5-6 BP 419 EP 431 DI 10.1016/S0026-2692(01)00012-X PG 13 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology SC Engineering; Science & Technology - Other Topics GA 443DJ UT WOS:000169324600004 ER PT J AU Robbins, AS Chao, SY Fonseca, VP AF Robbins, AS Chao, SY Fonseca, VP TI Body mass index and adiposity in active duty military members SO MILITARY MEDICINE LA English DT Letter C1 USAF, Populat Hlth Support Div, Med Operat Agcy, Brooks AFB, TX 78235 USA. RP Robbins, AS (reprint author), USAF, Populat Hlth Support Div, Med Operat Agcy, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD MAY PY 2001 VL 166 IS 5 BP IV EP V PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 653DA UT WOS:000181418900002 PM 11370214 ER PT J AU Bourgeois, JA Chozinski, JP Walker, DM Orr, K Wisniewski, W AF Bourgeois, JA Chozinski, JP Walker, DM Orr, K Wisniewski, W TI Psychiatric treatment and operational readiness: Clinical guidelines for air force practice SO MILITARY MEDICINE LA English DT Article; Proceedings Paper CT Military Psychiatry Update Meeting CY APR 04, 2000 CL SAN ANTONIO, TEXAS ID PERSONALITY-DISORDERS; AXIS-I; COGNITIVE THERAPY; MAJOR DEPRESSION; PHARMACOTHERAPY; EFFICACY AB Clinical criteria for psychiatric illnesses that are career limiting to active duty Air Force personnel are defined in Air Force Instruction (AFI) 48-123. The terms used in the AFI are not sufficiently specific to the standards of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). The authors review AFI 48-123 for conditions commonly seen in Air Force mental health practice and offer clinical interpretation of this AFI to bring it into line with DSM-IV. As a result of this synthesis, decisions regarding which mental health conditions warrant medical evaluation board disposition are clearer and more uniform. Clinicians and administrators are encouraged to refer to this paper for assistance in making decisions on mental health patients. C1 Univ Calif Davis, Dept Psychiat, Sacramento, CA 95817 USA. Wilford Hall USAF Med Ctr, Med Operat Squadron 59, Med Wing 59, Hosp Psychiat Serv, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Med Operat Squadron 59, Med Wing 59, Integrated Mental Hlth Clin, Lackland AFB, TX 78236 USA. RP Bourgeois, JA (reprint author), Univ Calif Davis, Dept Psychiat, Sacramento, CA 95817 USA. NR 19 TC 1 Z9 1 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD MAY PY 2001 VL 166 IS 5 BP 378 EP 381 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 653DA UT WOS:000181418900006 PM 11370197 ER PT J AU Sylvia, BM McMullen, P Levine, E Cruz, FB Gagnon, DA Malavakis, TL Williams, LA Schmelz, J Runzel, A Stevens, V Wootten, A AF Sylvia, BM McMullen, P Levine, E Cruz, FB Gagnon, DA Malavakis, TL Williams, LA Schmelz, J Runzel, A Stevens, V Wootten, A TI Prenatal care needs, availability, accessibility, use, and satisfaction: A comparison of military women within and outside the continental United States SO MILITARY MEDICINE LA English DT Article; Proceedings Paper CT Uniformed-Services-University-of-the-Health-Sciences-Research Day Meeting CY APR, 1999 CL BETHESDA, MARYLAND SP Uniformed Services Univ Hlth Sci Res ID LOW-BIRTH-WEIGHT; RACIAL DISPARITIES; PREGNANCY OUTCOMES; COST-EFFECTIVENESS; RISK; POPULATION; COHORT AB This article presents the results of a survey distributed to military women within and outside the continental United States (CONUS and OCONUS) who had received prenatal care and delivered at one of six Army, Navy, or Air Force military facilities. This comparative descriptive study was undertaken to determine from the mothers' perspective (1) their needs, availability, accessibility, use, satisfaction, and preferences for prenatal care services, and (2) if prenatal care and birth outcomes were significantly different for CONUS versus OCONUS women. Both groups reported a high degree of satisfaction with services, clinics/offices, and health care staff. Significant group differences were reported in transportation, length of travel time, and cost of traveling, with the CONUS group reporting greater problems with each. For both groups, quality and consistency of health care were the two most important factors in their preference of provider. More than 20% of the mothers reported receiving no information on some of the common concerns of pregnancy. There were no significant group differences with regard to infant birth weight or length of hospital stay. C1 Uniformed Serv Univ Hlth Sci, Grad Sch Nursing, Bethesda, MD 20814 USA. Naval Hosp, Nursing Serv, Camp Lejeune, NC 28547 USA. Womack Army Med Ctr, Ft Bragg, NC 28310 USA. Wilford Hall USAF Med Ctr, Clin Res Squadron 59, Lackland AFB, TX 78236 USA. USN Hosp, FPO, AP 96362 USA. Malcolm Grow Med Ctr, Womens Hlth Clin, Andrews AFB, MD 20762 USA. RP Sylvia, BM (reprint author), Uniformed Serv Univ Hlth Sci, Grad Sch Nursing, 4301 Jones Bridge Rd, Bethesda, MD 20814 USA. RI Sandall, Jane/D-4146-2009 OI Sandall, Jane/0000-0003-2000-743X NR 26 TC 2 Z9 2 U1 0 U2 1 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD MAY PY 2001 VL 166 IS 5 BP 443 EP 448 PG 6 WC Medicine, General & Internal SC General & Internal Medicine GA 653DA UT WOS:000181418900020 PM 11370210 ER PT J AU Shea, KJ Loy, DA AF Shea, KJ Loy, DA TI Bridged polysilsesquioxanes: Molecular engineering of hybrid organic-inorganic materials SO MRS BULLETIN LA English DT Review ID SOL-GEL PROCESS; INTRAMOLECULAR CONDENSATION-REACTIONS; SUPPORTED ORGANOMETALLIC COMPLEXES; PERIODIC MESOPOROUS ORGANOSILICAS; NONLINEAR-OPTICAL MATERIALS; DIFFERENT SPACER LENGTHS; SILYLATED COUMARIN DYES; INTERNAL DOPING METHOD; MODIFIED ELECTRODES; CYCLIC DISILSESQUIOXANES C1 Univ New Mexico, Albuquerque, NM 87131 USA. RP Shea, KJ (reprint author), AFRL, Wright Patterson AFB, OH USA. RI Loy, Douglas/D-4847-2009 OI Loy, Douglas/0000-0001-7635-9958 NR 131 TC 60 Z9 61 U1 2 U2 16 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 2001 VL 26 IS 5 BP 368 EP 376 DI 10.1557/mrs2001.90 PG 9 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 432UP UT WOS:000168714300012 ER PT J AU Vaia, RA Giannelis, EP AF Vaia, RA Giannelis, EP TI Polymer nanocomposites: Status and opportunities SO MRS BULLETIN LA English DT Article ID LAYERED-SILICATE NANOCOMPOSITES; MOLECULAR-DYNAMICS SIMULATIONS; POLYIMIDE-CLAY HYBRID; MELT INTERCALATION; EPOXY NANOCOMPOSITES; EPSILON-CAPROLACTAM; PHASE-BEHAVIOR; MONTMORILLONITE; COMPOSITES; MODEL C1 AFRL, ML, Wright Patterson AFB, OH USA. Cornell Univ, Dept Polymer Chem, Ithaca, NY 14853 USA. RP Vaia, RA (reprint author), AFRL, ML, Wright Patterson AFB, OH USA. NR 56 TC 262 Z9 267 U1 0 U2 44 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 2001 VL 26 IS 5 BP 394 EP 401 DI 10.1557/mrs2001.93 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 432UP UT WOS:000168714300015 ER PT J AU Brennan, CR Miller, RL Mathews, KA AF Brennan, CR Miller, RL Mathews, KA TI Split-cell exponential characteristic transport method for unstructured tetrahedral meshes SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID CHARACTERISTIC SPATIAL QUADRATURE; ORDINATES RADIATION TRANSPORT AB The nonlinear, exponential characteristic (EC) method is extended to unstructured meshes of tetrahedral cells in three-dimensional Cartesian coordinates. The split-cell approach developed for the linear characteristic (LC) method on such meshes is used. Exponential distributions of the source within a cell and of the inflow flux on upstream faces of the cell are assumed. The coefficients of these distributions are determined by nonlinear root solving so as to match the zeroth and first moments of the source or entering flux Good conditioning is achieved by casting the formulas for the moments of the source, inflow flux, and solution flux as stems of positive functions and by using accurate and robust algorithms for evaluation of those functions. Various test problems are used to compare the performance of the EC and LC methods. The EC method is somewhat less accurate than the LC method in regions of net out leakage brit is strictly positive and retains good accuracy with optically thick cells, as in shielding problems, unlike the LC method. The computational cost per cell is greater for the EC method bur the use of substantially coarser meshes can make the EC method less expensive in total cost. The EC method, unlike the LC method, may fail if negative cross sections or angular quadrature weights are used. It is concluded that the EC and LC methods should be practical, reliable, and complimentary schemes for these meshes. C1 USAF, Inst Technol, AFIT, ENP, Wright Patterson AFB, OH 45433 USA. RP Mathews, KA (reprint author), USAF, Inst Technol, AFIT, ENP, 2950 P St Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 19 TC 5 Z9 5 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 2001 VL 138 IS 1 BP 26 EP 44 PG 19 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 416ZR UT WOS:000167811000002 ER PT J AU Roberts, HW Charlton, DG Murchison, DF AF Roberts, HW Charlton, DG Murchison, DF TI Repair of non-carious amalgam margin defects SO OPERATIVE DENTISTRY LA English DT Article ID CARIES; RESTORATIONS AB This study investigated the microleakage associated with the repair of non-carious amalgam defects using flowable resin composite. Occlusal amalgam preparations were accomplished on 36 non-carious mandibular molars, A standardized 40-micron marginal defect was made by condensing amalgam against a mylar matrix strip, Specimens then underwent a corrosion protocol designed to simulate intraoral corrosion seen with amalgam restorations. The resultant specimens were divided into three treatment groups: 1) No treatment (control); 2) Air abrasion of the amalgam defect surface, acid etching of both amalgam and enamel surfaces, then placement of a flowable composite and 3) Air abrasion of the amalgam defect, application of a fifth-generation dentin bonding agent and placement of the flowable composite. Specimens were thermocycled, sealed with glass ionomer and fingernail polish to within 1 mm of repaired margins, then immersed in basic fuchsin for 24 hours. Specimens were sectioned and microleakage assessed. Results indicated that a flowable resin composite significantly reduced marginal microleakage compared to the control (p <0.05), There was no difference in microleakage between flowable resin composite repairs done with or without the use of a dentin-bonding agent. C1 USAF, Sch Aerosp Med, Dent Invest Serv, Great Lakes, IL 60088 USA. 35 Dent Squadron, Misawa AB, Japan. RP Roberts, HW (reprint author), USAF, Sch Aerosp Med, Dent Invest Serv, 310C B St,Bldg H, Great Lakes, IL 60088 USA. NR 9 TC 10 Z9 10 U1 0 U2 0 PU OPERATIVE DENTISTRY INC PI INDIANAPOLIS PA INDIANA UNIV SCHOOL DENTISTRY, ROOM S411, 1121 WEST MICHIGAN ST, INDIANAPOLIS, IN 46202-5186 USA SN 0361-7734 J9 OPER DENT JI Oper. Dent. PD MAY-JUN PY 2001 VL 26 IS 3 BP 273 EP 276 PG 4 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 430GY UT WOS:000168567200010 PM 11357570 ER PT J AU Gigantelli, JW Kincaid, MC Soparkar, CNS Lee, AG Carter, SR Yeatts, RP Holck, DEE Hartstein, ME Kennerdell, JS AF Gigantelli, JW Kincaid, MC Soparkar, CNS Lee, AG Carter, SR Yeatts, RP Holck, DEE Hartstein, ME Kennerdell, JS TI Orbital solitary fibrous tumor: Radiographic and histopathologic correlations SO OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY LA English DT Article; Proceedings Paper CT Annual Meeting of the North-American-Neuro-Ophthalmology-Society CY MAR, 1999 CL ASPEN, COLORADO SP N Amer Neuro Ophthalmol Soc ID GIANT-CELL ANGIOFIBROMA; UPPER RESPIRATORY-TRACT; PARANASAL SINUSES; SOFT-TISSUE; PATHOLOGICAL CORRELATION; NASAL CAVITY; PLEURA; MESOTHELIOMA; BENIGN; EXPRESSION AB Objective: To correlate the clinicopathologic and radiographic features characteristic of orbital solitary fibrous tumor (SFT). Methods: The diagnostic features and clinical outcome of seven adults with orbital SFT are retrospectively outlined. Orbital imaging was performed by ultrasonography, computed tomography, or magnetic resonance imaging. Some cases were imaged by multiple modalities. Histopathologic examination of each tumor specimen included standard light and immunohistochemical stains. Results: Heterogeneous internal composition was better appreciated on magnetic resonance imaging than on computed tomography. All cases undergoing magnetic resonance imaging showed T1 isointensity and T2 hypointensity relative to gray matter. Strong, generalized immunohistochemical reactivity to vimentin and CD34 validated the diagnosis of SFT and differentiated the specimens from other spindle cell neoplasms. After complete tumor resection, our patients remain tumor free with postoperative intervals of 15 to 45 months. Conclusions: Solitary fibrous tumor has now been reported in 26 orbits. No physical finding is pathognomonic, but several imaging traits are highly characteristic. Intralesional image heterogeneity and a predominantly low T2 signal intensity are distinctive of SFT. Complete tumor resection and immunohistologic specimen evaluation are emphasized. Clinicians should consider the diagnosis of SFT when confronted with an adult patient having an orbital soft tissue mass demonstrating the distinctive magnetic resonance imaging findings. C1 Univ Missouri, Dept Ophthalmol, Columbia, MO 65212 USA. St Louis Univ, Dept Ophthalmol, St Louis, MO 63103 USA. St Louis Univ, Dept Pathol, St Louis, MO 63103 USA. Plast Eye Surg Associates, PLLC, Houston, TX USA. Univ Texas, MD Anderson Canc Ctr, Dept Plast Surg, Houston, TX 77030 USA. Baylor Coll Med, Dept Ophthalmol, Houston, TX 77030 USA. Baylor Coll Med, Dept Neurol, Houston, TX 77030 USA. Baylor Coll Med, Dept Neurosurg, Houston, TX 77030 USA. Univ Calif San Francisco, Dept Ophthalmol, San Francisco, CA 94143 USA. Wake Forest Univ, Dept Ophthalmol, Winston Salem, NC 27109 USA. Wilford Hall USAF Med Ctr, Dept Ophthalmol, Lackland AFB, TX 78236 USA. Allegheny Ophthalm & Orbital Associates, PC, Pittsburgh, PA USA. RP Gigantelli, JW (reprint author), Nebraska Med Ctr, Dept Ophthalmol, 985540, Omaha, NE 68198 USA. NR 59 TC 20 Z9 24 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0740-9303 J9 OPHTHALMIC PLAST REC JI Ophthalmic Plast. Reconstr. Surg. PD MAY PY 2001 VL 17 IS 3 BP 207 EP 214 DI 10.1097/00002341-200105000-00011 PG 8 WC Ophthalmology; Surgery SC Ophthalmology; Surgery GA 435EA UT WOS:000168863400011 PM 11388388 ER PT J AU Kozlowski, SWJ Gully, SM Brown, KG Salas, E Smith, EM Nason, ER AF Kozlowski, SWJ Gully, SM Brown, KG Salas, E Smith, EM Nason, ER TI Effects of training goals and goal orientation traits on multidimensional training outcomes and performance adaptability SO ORGANIZATIONAL BEHAVIOR AND HUMAN DECISION PROCESSES LA English DT Article ID SELF-EFFICACY; LEARNING OUTCOMES; KNOWLEDGE STRUCTURES; SKILL GENERALIZATION; ACHIEVEMENT GOALS; FIT INDEXES; MOTIVATION; ABILITY; TASK; ACQUISITION AB This research examined the effects of mastery vs. performance training goals and learning and performance goal orientation traits on multidimensional outcomes of training. Training outcomes included declarative knowledge, knowledge structure coherence, training performance, and self-efficacy. We also examined the unique impact of the training outcomes on performance adaptability by predicting generalization to a more difficult and complex version of the task. The experiment involved 60 trainees learning a complex computer simulation over 2 days. The research model posited independent effects for training goals relative to goal orientation traits and independent contributions of training outcomes to the performance adaptability of trainees. The findings were consistent with the proposed model. In particular, self-efficacy and knowledge structure coherence made unique contributions to the prediction of performance adaptability after controlling for prior training performance and declarative knowledge. Implications and extensions are discussed. (C) 2001 Academic Press. C1 Michigan State Univ, Dept Psychol, E Lansing, MI 48824 USA. Rutgers State Univ, Dept Human Resource Management, Piscataway, NJ 08855 USA. Univ Iowa, Dept Management & Org, Iowa City, IA 52242 USA. Univ Cent Florida, Orlando, FL 32816 USA. Personnel Decis Res Inst, Minneapolis, MN 55402 USA. USAF, Mission Support Squadron 5, Washington, DC 20330 USA. RP Kozlowski, SWJ (reprint author), Michigan State Univ, Dept Psychol, 129 Psychol Res Bldg, E Lansing, MI 48824 USA. RI Brown, Kenneth/A-5844-2008; Gully, Stanley/D-1302-2012; KOZLOWSKI, STEVE/G-4614-2012; OI Brown, Kenneth/0000-0001-9428-9420; KOZLOWSKI, STEVE/0000-0002-5123-3424; Gully, Stanley/0000-0003-4037-3883 NR 78 TC 164 Z9 164 U1 2 U2 44 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0749-5978 J9 ORGAN BEHAV HUM DEC JI Organ. Behav. Hum. Decis. Process. PD MAY PY 2001 VL 85 IS 1 BP 1 EP 31 DI 10.1006/obhd.2000.2930 PG 31 WC Psychology, Applied; Management; Psychology, Social SC Psychology; Business & Economics GA 431VP UT WOS:000168652700001 ER PT J AU Brennan, J Moore, EJ Shuler, KJ AF Brennan, J Moore, EJ Shuler, KJ TI Prospective analysis of the efficacy of continuous intraoperative nerve monitoring during thyroidectomy, parathyroidectomy, and parotidectomy SO OTOLARYNGOLOGY-HEAD AND NECK SURGERY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Academy-of-Otolaryngology-Head-and-Neck-Surgery CY SEP 24-27, 2000 CL WASHINGTON, D.C. SP Amer Acad Otolaryngol Head & Neck Surg ID RECURRENT LARYNGEAL NERVE; SURGERY; EXPERIENCE; ELECTROMYOGRAPHY; MORBIDITY; PARALYSIS; PALSY AB OBJECTIVE: Continuous intraoperative electromyographic monitoring was prospectively performed in ail parotidectomies, thyroidectomies, and parathyroidectomies over approximately 5 years to assess the efficacy of this technology. STUDY DESIGN AND SETTING: Continuous intraoperative nerve monitoring with perioperative nerve assessment was performed, The postresection minimal stimulation level of the nerves was determined to evaluate if this level would predict nerve function postoperatively, RESULTS: Forty-four parotidectomies and 70 thyroid/parathyroid operations were performed with 140 nerves at risk (44 facial, 96 recurrent laryngeal). The incidence of temporary facial paralysis was 15.9% (7 of 44) and the incidence of permanent paralysis was 0%. The incidence of temporary recurrent laryngeal nerve paralysis in terms of nerves at risk was 1.0% (1 of 96), and the incidence of permanent recurrent laryngeal nerve paralysis was 0%. All patients with normally functioning facial and recurrent laryngeal nerves postoperatively had minimal stimulation levels less than or equal to 0.4 mA, CONCLUSION: Continuous Intraoperative nerve monitoring was associated with extremely low rates of temporary and permanent nerve paralysis in our series of 140 nerves at risk as compared to the rates documented in the literature. C1 Wilford Hall USAF Med Ctr, Dept Otolaryngol Head & Neck Surg, Lackland AFB, TX 78236 USA. David Grant Med Ctr, Dept Otolaryngol Head & Neck Surg, Travis AFB, CA USA. RP Brennan, J (reprint author), Wilford Hall USAF Med Ctr, Dept Otolaryngol Head & Neck Surg, 59th MDW-MMKR,2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 20 TC 49 Z9 51 U1 0 U2 0 PU MOSBY, INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0194-5998 J9 OTOLARYNG HEAD NECK JI Otolaryngol. Head Neck Surg. PD MAY PY 2001 VL 124 IS 5 BP 537 EP 543 DI 10.1067/mhn.2001.115402 PG 7 WC Otorhinolaryngology; Surgery SC Otorhinolaryngology; Surgery GA 432FV UT WOS:000168682300011 PM 11337659 ER PT J AU Lustig, LR Arts, HA Brackmann, DE Francis, HF Molony, T Megerian, CA Moore, GF Moore, KM Morrow, T Potsic, W Rubenstein, JT Srireddy, S Syms, CA Takahashi, G Vernick, D Wackym, PA Niparko, JK AF Lustig, LR Arts, HA Brackmann, DE Francis, HF Molony, T Megerian, CA Moore, GF Moore, KM Morrow, T Potsic, W Rubenstein, JT Srireddy, S Syms, CA Takahashi, G Vernick, D Wackym, PA Niparko, JK TI Hearing rehabilitation using the BAHA bone-anchored hearing aid: Results in 40 patients SO OTOLOGY & NEUROTOLOGY LA English DT Article DE conductive hearing loss; hearing aid; otosclerosis; otitis media; hearing implant; congenital aural atresia; bone conduction; skull base ID IMPLANTS AB Objective: This study evaluates the U.S. experience with the first 40 patients who have undergone audiologic rehabilitation using the BAHA bone-anchored hearing aid. Study Design: This study is a multicenter, nonblinded. retrospective case series. Setting: Twelve tertiary referral medical centers in the United States. Patients: Eligibility for BAHA implantation included patients with a hearing loss and an inability to tolerate a conventional hearing aid, with bone-conduction pure tone average levels at 60 dB or less at 0.5, 1, 2, and 4 kHz. Intervention: Patients who met audiologic and clinical criteria were implanted with the Pone-Anchored Hearing Aid (BAHA, Entific Corp.. Gothenburg. Sweden). Main Outcome Measures: Preoperative air- and bone-conduction thresholds and air-bone gap: postoperative BAHA-aided thresholds: hearing improvement as a result of implantation; implantation complications: and patient satisfaction. Results: The most common indications for implantation included chronic otitis media or draining ears (18 patients) and external auditory canal stenosis or aural atresia (7 patients). Overall. each patient had an average improvement of 32 +/- 19 dB with the use of the BAHA. Closure of the air-bone gap to within 10 dB of the preoperative bone-conduction thresholds (postoperative BAHA-aided threshold vs. preoperative bone-conduction threshold) occurred in 32 patients (80%), whereas closure to within 5 dB occurred in 24 patients (60%). Twelve patients (30%) demonstrated 'overclosure' of the preoperative bone-conduction threshold of the better hearing ear. Complications were limited to local infection and inflammation at the implant site in three patients. and failure to osseointegrate in one patient. Patient response to the implant was uniformly satisfactory. Only one patient reported dissatisfaction with the device. Conclusions: The BAHA bone-anchored hearing aid provides a reliable and predictable adjunct for auditory rehabilitation in appropriately selected patients, offering a means of dramatically improving hearing thresholds in patients with conductive or mixed hearing loss who are otherwise unable to benefit from traditional hearing aids. C1 Johns Hopkins Univ, Sch Med, Dept Otolaryngol Head & Neck Surg, Div Otol Neurotol & Skull Base Surg, Baltimore, MD 21287 USA. Univ Michigan, Med Ctr, Dept Otolaryngol Head & Neck Surg, Ann Arbor, MI 48109 USA. Ochsner Clin, Dept Otolaryngol Head & Neck Surg, New Orleans, LA USA. House Ear Clin, Los Angeles, CA USA. Univ Massachusetts, Med Ctr, Dept Otolaryngol Head & Neck Surg, Worcester, MA USA. Univ Nebraska, Med Ctr, Omaha, NE USA. Charleston ENT Associated LLC, Charleston, SC USA. Childrens Hosp Philadelphia, Dept Otolaryngol, Philadelphia, PA 19104 USA. Univ Iowa Hosp & Clin, Dept Otolaryngol Head & Neck Surg, Iowa City, IA 52242 USA. Wilford Hall USAF Med Ctr, Dept Otolaryngol Head & NeEck Surg, San Antonio, TX 78236 USA. Harvard Med Sch, Dept Otolaryngol Head & Neck Surg, Boston, MA USA. Med Coll Wisconsin, Dept Otolaryngol Head & Neck Surg, Milwaukee, WI 53226 USA. Johns Hopkins Univ, Dept Otolaryngol Head & Neck Surg, Baltimore, MD USA. RP Lustig, LR (reprint author), Johns Hopkins Univ, Sch Med, Dept Otolaryngol Head & Neck Surg, Div Otol Neurotol & Skull Base Surg, JHOC 6th Floor,601 N Caroline St, Baltimore, MD 21287 USA. RI Molony, Timothy/A-6047-2011 NR 21 TC 70 Z9 75 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1531-7129 J9 OTOL NEUROTOL JI Otol. Neurotol. PD MAY PY 2001 VL 22 IS 3 BP 328 EP 334 DI 10.1097/00129492-200105000-00010 PG 7 WC Clinical Neurology; Otorhinolaryngology SC Neurosciences & Neurology; Otorhinolaryngology GA 428DP UT WOS:000168446300011 PM 11347635 ER PT J AU Woodward, C Rao, SI AF Woodward, C Rao, SI TI Ab-initio simulation of isolated screw dislocations in bcc Mo and Ta SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID TRANSITION-METALS; DEFORMATION; ALLOYS AB The equilibrium core structure of isolated. (a/2) [111] screw dislocations are calculated using a first-principles pseudopotential plane-wave method within the local-density approximation of density functional theory. The long-range strain field of the dislocation is treated using a variation of the recently developed lattice Green's function boundary condition method. This flexible boundary method allows the dislocation to be contained in a very small simulation cell without compromising the fidelity of the final core configuration. Supercells of 168, 270 and 504 atoms are used to evaluate the local screw and edge displacements of the (a/2) [111] screw dislocation in Mo and Ta. These results are contrasted with previous results from atomistic and dipole array calculations. We rnd that the isolated screw dislocations are evenly spread on three conjugate (110) planes for both Mo and Ta. The twinning-antitwinning anisotropy is calculated in Mo by applying a pure glide stress on the (112) plane. In these simulations the dislocation always moves on a {110} plane. The lattice frictional stress to move a straight screw dislocation on the (112) plane in the antitwinning and twinning sense is estimated at 0.025 mu and 0.0125 mu respectively. This is in good agreement with parallel atomistic simulations and experimental measurements of the slip asymmetry. C1 USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, Dayton, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Woodward, C (reprint author), USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, Dayton, OH 45433 USA. NR 23 TC 90 Z9 90 U1 3 U2 23 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2001 VL 81 IS 5 BP 1305 EP 1316 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 433KC UT WOS:000168757700017 ER PT J AU Rao, SI Woodward, C AF Rao, SI Woodward, C TI Atomistic simulations of (a/2)< 111 > screw dislocations in bcc Mo using a modified generalized pseudopotential theory potential SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID TRANSITION-METALS; INTERATOMIC POTENTIALS AB Atomistic simulations using a modified generalized pseudopotential theory potential and Green's function boundary conditions were employed to determine the Peierls stress of rigid straight (a/2) [111] screw dislocations for the application of shear stresses on {110}- and {112}-type planes in bcc Mo. It is found that the Peierls stress of (a/2) [111] screw dislocations for the application of shear stress on the {110} planes is (0.0175-0.020)mu. Large twinning-antitwinning asymmetry is found for the application of pure shear stress on the {112} planes with the Peierls stress along the twinning direction being (0.0125-0.020)mu and along the antitwinning direction to be (0.050-0.0562)mu. The Peierls stress of screw dislocations for the application of tensile and compressive stresses along {001}, {110}, {111} and {201} directions were also determined. A large tension-compression asymmetry is observed for the {001}, {110} and {111} directions. This is a manifestation of the twinning-antitwinning asymmetry observed in the pure shear stress calculations. A tension-compression asymmetry is also observed for the {201} direction, indicating that non-glide stress effects are also important in determining the Peierls stress. To facilitate an understanding of (a/2) [111] screw dislocation motion by the kink pair mechanism, the core structure and energetics of six possible kinks and two antiphase defects on (a/2) [111] screw dislocations were also determined. It is found that the kink pair formation energy at infinite separation distance varies between 1.46 and 2.10 eV, which is in reasonable accord with the experimental value of 1.27 eV. C1 USAF, Mat Directorate, Wright Lab, Wright Patterson AFB, Dayton, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Rao, SI (reprint author), USAF, Mat Directorate, Wright Lab, Wright Patterson AFB, Dayton, OH 45433 USA. NR 13 TC 48 Z9 49 U1 1 U2 5 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD MAY PY 2001 VL 81 IS 5 BP 1317 EP 1327 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 433KC UT WOS:000168757700018 ER PT J AU Davidchack, RL Lai, YC Gavrielides, A Kovanis, V AF Davidchack, RL Lai, YC Gavrielides, A Kovanis, V TI Regular dynamics of low-frequency fluctuations in external cavity semiconductor lasers SO PHYSICAL REVIEW E LA English DT Article ID UNSTABLE PERIODIC-ORBITS; POWER-DROPOUT EVENTS; OPTICAL FEEDBACK; CHAOTIC ATTRACTORS; STATISTICS; BIFURCATION; INSTABILITY; TURBULENCE; SUBJECT; SYSTEM AB It is commonly believed that the dynamics responsible for low-frequency fluctuations (LFF's) in external cavity semiconductor lasers is stochastic or chaotic. A common approach to address the origin of LFF's is to investigate the dynamical behavior of, and the interaction among, various external cavity modes in the Lang-Kobayashi (LK) paradigm. In this paper, we propose a framework for understanding of the LFFs based on a different set of fundamental solutions of the LK equations, which are periodic or quasiperiodic, and which are characterized by a sequence of time-locked pulses with slowly varying magnitude. We present numerical evidence and heuristic arguments, indicating that the dynamics of LFF's emerges as a result of quasiperiodic bifurcations from these solutions as the pumping current increases. Regular periodic solutions can actually be observed when (1) the feedback level is moderate, (2) pumping current is below solitary threshold, and (3) the linewidth enhancement factor is relatively large. C1 Univ Leicester, Dept Math & Comp Sci, Leicester LE1 7RH, Leics, England. Arizona State Univ, Ctr Syst Sci & Engn, Dept Math, Tempe, AZ 85287 USA. Arizona State Univ, Ctr Syst Sci & Engn, Dept Elect Engn, Tempe, AZ 85287 USA. Arizona State Univ, Ctr Syst Sci & Engn, Dept Phys, Tempe, AZ 85287 USA. USAF, Res Lab, DELO, Nonlinear Opt Grp, Albuquerque, NM 87117 USA. Univ New Mexico, Dept Elect & Comp Engn, Albuquerque, NM 87131 USA. RP Davidchack, RL (reprint author), Univ Leicester, Dept Math & Comp Sci, Leicester LE1 7RH, Leics, England. RI Davidchack, Ruslan/D-8030-2011 OI Davidchack, Ruslan/0000-0001-9418-5322 NR 42 TC 13 Z9 13 U1 0 U2 2 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 MAY PY 2001 VL 63 IS 5 AR 056206 DI 10.1103/PhysRevE.63.056206 PN 2 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 432ZL UT WOS:000168730800044 PM 11414989 ER PT J AU Mitchell, AM Delery, J AF Mitchell, AM Delery, J TI Research into vortex breakdown control SO PROGRESS IN AEROSPACE SCIENCES LA English DT Review ID LEADING-EDGE VORTICES; DELTA; FLAPS AB Vortex breakdown remains a significant and intriguing phenomenon that can have detrimental or beneficial effects, depending on the application. Thus there is a strong need to both better understand the phenomenon and to control it, either to prevent breakdown or to promote it. For the past 50 years, multiple Row control techniques have demonstrated the ability to manipulate the vortex breakdown location over slender delta wings at high angles of attack. An extensive historical review of these diverse control methods, mechanical and pneumatic, steady or periodic., is presented and discussed; however, none of these techniques has clearly demonstrated a superior efficiency or effectiveness in controlling either the vortical flow structure or the vortex breakdown location. Each technique, does, on the other hand, provide a unique approach to the control of the vortex breakdown depending on the desired outcome. There are still major obstacles to overcome before the control of vortex breakdown is implemented in flight. For example, oscillations of the vortex breakdown locations are difficult to quantify and to identify. The often poor effectiveness of control techniques can be in great part attributed to insufficient knowledge of breakdown and in an inability to accurately predict breakdown. When considering the large quantity of studies aimed at vortex breakdown control and their relative success, it is clear that decisive progress in this domain will require further basic investigations to clearly elucidate the physics of the phenomenon and to improve the predictive capability. (C) 2001 Elsevier Science Ltd All rights reserved. C1 Ctr Chalais Meudon, Off Natl Etud & Rech Aerosp, Fundamental & Expt Aerodynam Dept, F-92190 Meudon, France. USAF Acad, Dept Aeronaut, Colorado Springs, CO 80840 USA. RP Delery, J (reprint author), Ctr Chalais Meudon, Off Natl Etud & Rech Aerosp, Fundamental & Expt Aerodynam Dept, 8 Rue de Vertugadins, F-92190 Meudon, France. NR 94 TC 52 Z9 54 U1 2 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0376-0421 J9 PROG AEROSP SCI JI Prog. Aeosp. Sci. PD MAY PY 2001 VL 37 IS 4 BP 385 EP 418 DI 10.1016/S0376-0421(01)00010-0 PG 34 WC Engineering, Aerospace SC Engineering GA 467UB UT WOS:000170721200002 ER PT J AU Osborne, JH Blohowiak, KY Taylor, SR Hunter, C Bierwagon, G Carlson, B Bernard, D Donley, MS AF Osborne, JH Blohowiak, KY Taylor, SR Hunter, C Bierwagon, G Carlson, B Bernard, D Donley, MS TI Testing and evaluation of nonchromated coating systems for aerospace applications SO PROGRESS IN ORGANIC COATINGS LA English DT Article DE chromated; coatings; primer; sol-gel process; electrochemical impendance spectroscopy (EIS); electrochemical noise method (ENM); corrosion; corrosion inhibitors AB The advanced corrosion resistant aircraft coatings program (ACRAC) is part of the Air Force strategy to improve performance and reduce environmental impact of coatings used on Air Force weapon systems. The program addresses the Air Force near and mid-term strategies to eliminate chromate corrosion inhibitors and reduce steps in the outer mold line coating process. Evaluation of the coating process (surface preparation, conversion coating, primer, topcoat) as a system is a key feature of the ACRAC program. Results to date indicate that the current-state-of-the-are nonchromated coating systems are significantly less effective than those with chromate. A chromate conversion coating is required for the nonchromate primer system to meet minimum requirements. Sol-gel-process based conversion coatings can replace chromate conversion coatings provided a chromated primer is used. Several approaches to incorporating inhibitors into sol-gel coatings are discussed. Electrochemical methods for testing coating performance are discussed and a new procedure based on impedance spectroscopy for evaluating active damage repair is presented. (C) 2001 Published by Elsevier Science B.V. C1 Boeing Co, Seattle, WA 98124 USA. Univ Virginia, Dept Mat Sci, Charlottesville, VA 22903 USA. N Dakota State Univ, Dept Polymers & Coatings, Fargo, ND 58105 USA. Deft Inc, Ind Div, Irvine, CA 92714 USA. USAF, Res Lab, Nonmetall Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Osborne, JH (reprint author), Boeing Co, POB 3999,M-S 73-09, Seattle, WA 98124 USA. NR 18 TC 83 Z9 88 U1 2 U2 19 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0300-9440 J9 PROG ORG COAT JI Prog. Org. Coat. PD MAY PY 2001 VL 41 IS 4 BP 217 EP 225 DI 10.1016/S0300-9440(01)00132-1 PG 9 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 449YT UT WOS:000169715300002 ER PT J AU Vreugdenhil, AJ Donley, MS Grebasch, NT Passinault, RJ AF Vreugdenhil, AJ Donley, MS Grebasch, NT Passinault, RJ TI Applications of vibrational spectroscopy to the analysis of novel coatings SO PROGRESS IN ORGANIC COATINGS LA English DT Article DE step scan; digital signal processing; photoacoustic spectroscopy; novel coatings ID QUANTITATIVE-ANALYSIS; FILMS; POLYURETHANES; SURFACE AB Precise analysis is essential to the development of novel coating technologies and to the systematic modification of metal surfaces. Ideally, these analysis techniques will provide molecular information and will be sensitive to changes in the chemical environment of interfacial species. Many of the techniques available in the field of vibrational spectroscopy demonstrate some of these characteristics. Examples of the ways in which FT-IR spectroscopy are applied to the investigation of coatings at AFRL will be described. Attenuated total reflectance (ATR), specular reflectance and photoacoustic spectroscopy (PAS) are important techniques for the analysis of surfaces. Both ATR and PAS can be used to provide depth-profiling information crucial for the study of coatings. Recent developments in digital signal processing (DSP) and step scan interferometry which have dramatically improved the reliability and ease of use of PAS for depth analysis will be discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. WL MLBT, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Mat & Mfg Directorate, Dayton, OH 45433 USA. RP Vreugdenhil, AJ (reprint author), Univ Dayton, Res Inst, 300 Coll Pk, Dayton, OH 45469 USA. NR 19 TC 10 Z9 10 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0300-9440 J9 PROG ORG COAT JI Prog. Org. Coat. PD MAY PY 2001 VL 41 IS 4 BP 254 EP 260 DI 10.1016/S0300-9440(01)00136-9 PG 7 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 449YT UT WOS:000169715300007 ER PT J AU Khobaib, M Rensi, A Matikas, T Donley, MS AF Khobaib, M Rensi, A Matikas, T Donley, MS TI Real time mapping of corrosion activity under coatings SO PROGRESS IN ORGANIC COATINGS LA English DT Article DE corrosion activity; real time mapping; electrochemical impedance spectroscopy; electrochemical noise methods; scanning vibrating electrode technique; sol-gel based coating systems AB Current accelerated testing of aircraft coating systems for corrosion protection relies heavily on salt spray methods. Electrochemical techniques such as electrochemical impedance spectroscopy GETS) and electrochemical noise methods (ENM) provide insight into the global properties of a coating system, and bath techniques are being used on a limited basis. However, there is a need to investigate corrosion events with greater spatial resolution under coatings at the metal/coating interface. Such corrosion activity may be related to coating defects and variations in the surface chemistry of the underlying metal. The scanning vibrating electrode technique (SVET) has, been developed to allow high spatial resolution investigation of localized corrosion activity that may be associated with coating defects or galvanic coupled regions of the metal surface. The SVET offers high resolution in current measurements of the order of 0.5 muA/cm(2) and is able to detect in-situ initiation and progress of corrosion activity under a protective coating. Using the SVET, minute variations in d.c. current associated with localized corrosion activity are detected and used to map both anodic and cathodic corrosion activities in a localized area. The difference in initial corrosion activity under various coatings can be correlated to the performance Life of the coatings. The application of SVET to aircraft coatings and corrosion is reported to demonstrate the utility of this important new electrochemical tool. In the current study, the SVET was used to discriminate the corrosion protection performance of selected sol-gel based coating systems. Sol-gel based surface treatments are being developed as part of an environmentally compliant coating system alternative to the currently used chromate-based systems, The SVET results are compared with data obtained from chromium inhibition coating systems. The SVET analyses are compared with electrochemical impedance measurements. The comparison of such data will provide the basis to adopt SVET measurements as an early performance discriminator for newly developed coating systems. (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Res Labs, Mat & Mfg Directorate, Nonmetall Mat Div,Coatings Res Grp, Wright Patterson AFB, OH 45433 USA. RP Khobaib, M (reprint author), Univ Dayton, Res Inst, 300 Coll Pk, Dayton, OH 45469 USA. EM mohammad.khobaib@afrl.af.mil RI Matikas, Theodore/I-2803-2012 NR 6 TC 26 Z9 29 U1 3 U2 11 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0300-9440 J9 PROG ORG COAT JI Prog. Org. Coat. PD MAY PY 2001 VL 41 IS 4 BP 266 EP 272 DI 10.1016/S0300-9440(01)00141-2 PG 7 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 449YT UT WOS:000169715300009 ER PT J AU Voevodin, NN Grebasch, NT Soto, WS Kasten, LS Grant, JT Arnold, FE Donley, MS AF Voevodin, NN Grebasch, NT Soto, WS Kasten, LS Grant, JT Arnold, FE Donley, MS TI An organically modified zirconate film as a corrosion-resistant treatment for aluminum 2024-T3 SO PROGRESS IN ORGANIC COATINGS LA English DT Article DE aluminum alloy; corrosion; sol-gel; FTIR; XPS AB Current coating systems for aircraft corrosion protection are based on a traditional chromate surface treatment, primer, and topcoat. The Air Force is seeking environmentally benign corrosion-resistant surface treatments for aluminum-skinned aircraft as a replacement for environmentally hazardous surface treatments involving chromates. Performance of replacement treatments must be able to satisfy the durability needed for dramatically extended lifetimes, be compatible with present and future environmental requirements, and be easily integrated into current primer/topcoat paint systems. Organically modified zirconate sol-gel films were investigated as an environmentally compliant replacement for chromated surface treatments, which included functionalized components to tailor the chemistry at both the aluminum oxide substrate/surface treatment interface and the surface treatment/topcoat interface. Sol-gel films were applied to aluminum 2024-T3 alloy coupons, and the resulting film chemistry was investigated. FTIR was used to identify organic components in the film and X-ray photoelectron spectroscopy was used to investigate the interface chemistry. The result of the chemically modified sol-gel synthesis was a coating in which a concentration gradient was formed at the surface, which is discussed. The corrosion protection attributes of these films was also studied and the electrochemical evaluation of sol-gel films will be discussed, both as stand-alone coatings and as part of a full coating system. Organically modified sol-gels exhibited significantly better protection in terms of barrier properties in comparison to a typical chromate-based processes. The resulting data from evaluations of sol-gel produced coatings show promise towards the goal of producing a robust chemical interaction/bonding of such corrosion-resistant coatings on the surface of aluminum-skinned aircraft without the use of environmentally hazardous chromate agents. (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Nonstruct Mat Branch, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Inst Res, Dayton, OH 45469 USA. Systran Corp, Dayton, OH USA. So Ohio Council Higher Educ, Dayton, OH USA. RP Voevodin, NN (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Nonstruct Mat Branch, Bldg 654, Wright Patterson AFB, OH 45433 USA. NR 7 TC 67 Z9 72 U1 1 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0300-9440 J9 PROG ORG COAT JI Prog. Org. Coat. PD MAY PY 2001 VL 41 IS 4 BP 287 EP 293 DI 10.1016/S0300-9440(01)00156-4 PG 7 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 449YT UT WOS:000169715300012 ER PT J AU Scholfield, DW Borovina, JL Copeland, RP AF Scholfield, DW Borovina, JL Copeland, RP TI A novel primary inductor for a dual tuned resonant transformer SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB A primary inductor for a dual tuned resonant transformer of some limited utility has been developed which merges the capacitance utilized for energy storage into the inductor, creating a composite electrical component. The resulting device, and the mathematical treatment to predict performance, are described. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Univ New Mexico, Dept Elect & Comp Engn, Albuquerque, NM 87131 USA. ITT Syst, Kaman Sci Div, Albuquerque, NM 87110 USA. RP Scholfield, DW (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 6 TC 0 Z9 0 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 2001 VL 72 IS 5 BP 2438 EP 2442 DI 10.1063/1.1367354 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 424VH UT WOS:000168254300033 ER PT J AU Crowley, JD Shelton, J Iverson, AJ Burton, MP Dalrymple, NC Bishoff, JT AF Crowley, JD Shelton, J Iverson, AJ Burton, MP Dalrymple, NC Bishoff, JT TI Laparoscopic and computed tomography-guided percutaneous radiofrequency ablation of renal tissue: Acute and chronic effects in an animal model SO UROLOGY LA English DT Article ID INTERSTITIAL THERMAL ABLATION; CATHETER ABLATION; CLINICAL-TRIAL; TUMORS; CANCER; FEASIBILITY; CARCINOMA; SAFETY; ENERGY; VIVO AB Objectives. To evaluate the laparoscopic and percutaneous delivery of impedance-based radiofrequency ablation (RFA) of the kidney by studying the acute and chronic clinical, radiographic, and histopathologic effects in the porcine model. Methods. Eight kidneys from 4 pigs underwent laparoscopic RFA. Six kidneys from 3 additional pigs received computed tomography (CT)-guided, percutaneous RFA. CT scans were performed immediately after RFA and before harvest at 2 hours, 24 hours, 3 weeks, and 13 weeks. The gross, radiographic, and histopathologic changes were recorded for each period. Results, Grossly, the RFA lesions were sharply demarcated, measuring 3 to 5 cm. Two major complications (14%) occurred (one urinoma, one psoas muscle injury) in 14 ablations. No deaths or significant blood loss occurred as a result of RFA. Radiographically, the immediate CT scanning demonstrated small perinephric hematomas and wedge-shaped defects. Delayed CT showed nonenhancing defects up to 5 cm. Color-flow and power Doppler were unable to distinguish significant tissue changes during RFA. The histopathologic evaluation revealed marked inflammation surrounding the necrotic regions in the early lesions; chronic lesions were characterized by dense fibrosis. The tissue temperatures ranged from 62 degrees to 118 degreesC in the area of ablation. Conclusions, RFA is readily delivered laparoscopically or percutaneously with minimal morbidity. Impedance-based application of radiofrequency energy allows monitoring and control of ablation. Using a multiantenna probe, areas of tissue up to 5 cm can be completely destroyed. The RFA lesion can be monitored as a nonenhancing cortical defect on CT. UROLOGY 57: 976-980, 2001. (C) 2001, Elsevier Science Inc. C1 Wilford Hall USAF Med Ctr, Dept Urol, MMKU, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Dept Pathol, Lackland AFB, TX 78236 USA. RP Bishoff, JT (reprint author), Wilford Hall USAF Med Ctr, Dept Urol, MMKU, Suite 1,2200 Berquist Dr, Lackland AFB, TX 78236 USA. NR 24 TC 72 Z9 80 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0090-4295 J9 UROLOGY JI UROLOGY PD MAY PY 2001 VL 57 IS 5 BP 976 EP 980 DI 10.1016/S0090-4295(00)01129-8 PG 5 WC Urology & Nephrology SC Urology & Nephrology GA 431RL UT WOS:000168644300029 PM 11337311 ER PT J AU Ranatunga, V Gunasekera, JS Frazier, WG Hur, KD AF Ranatunga, V Gunasekera, JS Frazier, WG Hur, KD TI Use of UBET for design of flash gap in closed-die forging SO JOURNAL OF MATERIALS PROCESSING TECHNOLOGY LA English DT Article; Proceedings Paper CT International Symposium on Advanced Forming and Die Manufacturing Technology (AFDM 99) CY SEP 07-09, 1999 CL HAEUNDAE, SOUTH KOREA DE flash gap; closed-die forging; UBET; axisymmetric dies AB An upper bound elemental technique (UBET) has been proposed for the design of the flash gay in closed-die forging operations of axisymmetric shapes. The developed method has been applied to analyze the forging load, die-cavity filling, and effective strain and strain rate distributions in axisymmetric closed-die forging with a rib-web type of cavity. The forging process has been superimposed with two sub-stages called the extrusion and the back-fill stages. The total die load required for extrusion and back fill are calculated separately and a maximum allowable extrusion gap is proposed for a given percentage die-fill. FEM simulations have been carried out with different die geometries and the results are in good agreement with UBET predictions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Dong Eui Univ, Dept Mech Engn, Pusanjin Ku, Pusan 614714, South Korea. Ohio Univ, Dept Mech Engn, Athens, OH 45701 USA. USAF, Res Lab, Dayton, OH USA. RP Hur, KD (reprint author), Dong Eui Univ, Dept Mech Engn, Pusanjin Ku, Kaya Dong San24, Pusan 614714, South Korea. NR 6 TC 10 Z9 10 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-0136 J9 J MATER PROCESS TECH JI J. Mater. Process. Technol. PD APR 25 PY 2001 VL 111 IS 1-3 BP 107 EP 112 DI 10.1016/S0924-0136(01)00491-5 PG 6 WC Engineering, Industrial; Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 428KZ UT WOS:000168462000020 ER PT J AU Gonzalez, E Dhanda, R Bamshad, M Mummidi, S Geevarghese, R Catano, G Anderson, SA Walter, EA Stephan, KT Hammer, MF Mangano, A Sen, L Clark, RA Ahuja, SS Dolan, MJ Ahuja, SK AF Gonzalez, E Dhanda, R Bamshad, M Mummidi, S Geevarghese, R Catano, G Anderson, SA Walter, EA Stephan, KT Hammer, MF Mangano, A Sen, L Clark, RA Ahuja, SS Dolan, MJ Ahuja, SK TI Global survey of genetic variation in CCR5, RANTES, and MIP-1 alpha: Impact on the epidemiology of the HIV-1 pandemic SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID IMMUNODEFICIENCY-VIRUS TYPE-1; CHEMOKINE RECEPTOR-5 GENE; DISEASE PROGRESSION; INFECTION; AIDS; POLYMORPHISM; TRANSMISSION; RESISTANCE; PATHOGENESIS; DETERMINANTS AB Expression of CC chemokine receptor 5 (CCR5), the major coreceptor for HIV-1 cell entry, and its ligands (e.g., RANTES and MIP-1 alpha) is widely regarded as central to the pathogenesis of HIV-1 infection. By surveying nearly 3,000 HIV+ and HIV- individuals from worldwide populations for polymorphisms in the genes encoding RANTES, MIP-1 alpha: and CCR5, we show that the evolutionary histories of human populations have had a significant impact on the distribution of variation in these genes, and that this may be responsible, in part, for the heterogeneous nature of the epidemiology of the HIV-1 pandemic, The varied distribution of RANTES haplotypes (AC, GC, and AC) associated with population-specific HIV-I transmission- and disease-modifying effects is a striking example. Homozygosity for the AC haplotype was associated with an increased risk of acquiring HIV-1 as well as accelerated disease progression in European Americans, but not in African Americans. Yet. the prevalence of the ancestral AC haplotype is high in individuals of African origin, but substantially lower in non-Africans. In a Japanese cohort, AG-containing RANTES haplotype pairs were associated with a delay in disease progression; however, we now show that their contribution to HIV-1 pathogenesis and epidemiology in other parts of the world is negligible because the AG haplotype is infrequent in non-far East Asians. Thus, the varied distribution of RANTES, MIP-1 alpha, and CCR5 haplotype pairs and their population-specific phenotypic effects on HIV-1 susceptibility and disease progression results in a complex pattern of biological determinants of HIV-1 epidemiology. These findings have important implications for the design, assessment, and implementation of effective HIV-I intervention and prevention strategies. C1 S Texas Vet Hlth Care Syst, San Antonio, TX 78229 USA. Univ Texas, Hlth Sci Ctr, San Antonio, TX 78229 USA. Purdue Pharmaceut, Norwalk, CT 06901 USA. Univ Utah, Dept Pediat, Salt Lake City, UT 84112 USA. Wilford Hall USAF Med Ctr, Henry M Jackson Fdn, San Antonio, TX 78236 USA. Wilford Hall USAF Med Ctr, Infect Dis Serv, San Antonio, TX 78236 USA. Univ Arizona, Tucson, AZ 85721 USA. Hosp Pediat JP Garrahan, Buenos Aires, DF, Argentina. RP Dolan, MJ (reprint author), S Texas Vet Hlth Care Syst, 7703 Floyd Curl Dr, San Antonio, TX 78229 USA. RI Mummidi, Srinivas/C-1004-2008 OI Mummidi, Srinivas/0000-0002-4068-6380 FU NIAID NIH HHS [R37 AI046326, AI43279, AI46326, R21 AI046326, R01 AI043279, R01 AI046326] NR 32 TC 185 Z9 192 U1 0 U2 5 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD APR 24 PY 2001 VL 98 IS 9 BP 5199 EP 5204 DI 10.1073/pnas.091056898 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 425VC UT WOS:000168311500072 PM 11320252 ER PT J AU Xie, QH Brown, JL Van Nostrand, JE AF Xie, QH Brown, JL Van Nostrand, JE TI Cooperative nucleation and evolution in InGaAs quantum dots in multiply stacked structures SO APPLIED PHYSICS LETTERS LA English DT Article ID ISLANDS; GROWTH; ARRAYS AB We report a type of vertical self-organization of In0.6Ga0.4As quantum dots (QDs) wherein the dot density for the top layer (N-T) doubles that of the seed layer (N-S). The experimental observation fits well with a scheme of QD vertical self-organization accompanied by additional cooperative dot nucleation at the face centers of an approximate two-dimensional array defined by the embedded seed dots. The dots in the top layer undergo a shape transition from {023} to {011} and a simultaneous shape stabilization and size equalization. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. RP Brown, JL (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 14 TC 5 Z9 5 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 23 PY 2001 VL 78 IS 17 BP 2491 EP 2493 DI 10.1063/1.1365102 PG 3 WC Physics, Applied SC Physics GA 425RC UT WOS:000168304600026 ER PT J AU Fang, ZQ Kim, JW Yu, PW AF Fang, ZQ Kim, JW Yu, PW TI Metastability of defects in p-GaAs grown from a Ga-rich melt SO APPLIED PHYSICS LETTERS LA English DT Article ID DOUBLE ACCEPTOR; BULK GAAS; PHOTOLUMINESCENCE AB We report the observation of metastability for defects in Si-doped p-GaAs grown from a Ga-rich melt. A configuration change occurs suddenly at a critical temperature (near 120 K) during cooldown scans, giving rise to discontinuous deep-level transient spectra. A similar phenomenon was observed on electron-irradiated float-zone-refined Si and explained in terms of entropy variations in the configurational space. We believe that the metastability found in the p-GaAs sample is also due to a barrierless transformation of defect configuration, driven by variations in both entropy and the charge state of Ga-As. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Kwang Ju Inst Sci & Technol, Dept Informat & Commun, Kwangju 500712, South Korea. RP Fang, ZQ (reprint author), Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. NR 14 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 23 PY 2001 VL 78 IS 17 BP 2506 EP 2508 DI 10.1063/1.1365100 PG 3 WC Physics, Applied SC Physics GA 425RC UT WOS:000168304600031 ER PT J AU Cliver, EW Ling, AG AF Cliver, EW Ling, AG TI 22 year patterns in the relationship of sunspot number and tilt angle to cosmic-ray intensity SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic rays; solar-terrestrial relations ID HELIOSPHERIC CURRENT SHEET; MAGNETIC-FIELD; MODULATION; TRANSPORT; REGIONS; DRIFT; SUN AB A comparison of 27 day averages of the sunspot number with the Galactic cosmic-ray intensity observed at Climax reveals a 22 yr pattern. The 11 yr cosmic-ray cycle appears to lag the sunspot cycle by similar to1 yr for odd-numbered cycles such as 19 and 21. During even-numbered cycles the sunspot number and cosmic-ray intensity curves are essentially in phase. A similar pattern is apparent in a comparison of the tilt angle of the heliospheric current sheet (HCS) with cosmic-ray intensity for the last three solar cycles (21-23). The tilt angle evolution on the rise of the last three cycles was remarkably similar, while the decline of the tilt angle from high values at the maximum of cycle 21 (similar to 1980) was more gradual than that observed following the maximum of cycle 22 (similar to 1990) or that inferred from coronal hole areas for cycle 20 (similar to 1970). The reduced responsiveness of cosmic rays to sunspot or tilt angle increases on the rise of odd-numbered solar cycles is consistent with a drift effect. A difference in the evolution of large-scale fields on the decay of even- and odd-numbered cycles may contribute to more gradual recovery of cosmic-ray intensity following the maxima of odd-numbered cycles. The onset of modulation in odd-numbered cycles, and of diffusion/convection-dominated modulation in even- numbered cycles, appears to begin when the tilt angle of the HCS exceeds similar to 50 degrees. C1 USAF, Res Lab, Space Vehicles Directorate VSBXS, Hanscom AFB, MA 01731 USA. Radex Inc, Bedford, MA 01730 USA. RP Cliver, EW (reprint author), USAF, Res Lab, Space Vehicles Directorate VSBXS, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 28 TC 41 Z9 41 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 2001 VL 551 IS 2 BP L189 EP L192 DI 10.1086/320022 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 427BJ UT WOS:000168384700016 ER PT J AU Heim, LJ AF Heim, LJ TI Evaluation and differential diagnosis of dyspareunia SO AMERICAN FAMILY PHYSICIAN LA English DT Article ID VULVAR VESTIBULITIS SYNDROME; SEXUAL DYSFUNCTION; PELVIC PAIN; WOMEN; PREVALENCE; ABUSE AB Dyspareunia is genital pain associated with sexual intercourse. Although this condition has historically been defined by psychologic theories, the current treatment approach favors an integrated pain model. Identification of the initiating and promulgating factors is essential to reaching a successful diagnosis. The differential diagnoses include vaginismus, inadequate lubrication, atrophy and vulvodynia (vulvar vestibulitis). Less common etiologies are endometriosis, pelvic congestion, adhesions or infections, and adnexal pathology. Urethral disorders, cystitis and interstitial cystitis may also cause painful intercourse. The location of the pain may be described as entry or deep. Vulvodynia, atrophy, inadequate lubrication and vaginismus are associated with painful entry. Deep pain occurs with the other conditions previously noted, The physical examination may reproduce the pain, such as localized pain with vulvar vestibulitis, when the vagina is touched with a cotton swab. The involuntary spasm of vaginismus may be noted with insertion of an examining finger or speculum. Palpation of the lateral vaginal walls, uterus, adnexa and urethral structures helps identify the cause. An understanding of the present organic etiology must be integrated with an appreciation of the ongoing psychologic factors and negative expectations and attitudes that perpetuate the pain cycle, C1 USAF, MC, Eglin AFB, FL 32542 USA. RP Heim, LJ (reprint author), SGOL, MDOS 96, 307 Boatner Rd,Ste 114, Eglin AFB, FL 32542 USA. NR 31 TC 32 Z9 34 U1 1 U2 5 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 APR 15 PY 2001 VL 63 IS 8 BP 1535 EP 1544 PG 10 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 424KM UT WOS:000168231500007 PM 11327429 ER PT J AU Huang, DH Singh, A Cardimona, DA Morath, C AF Huang, DH Singh, A Cardimona, DA Morath, C TI Compensation of charge fluctuations in quantum wells with dual tunneling and photon-assisted escape paths SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID INFRARED PHOTODETECTORS; DARK CURRENT; FIELD AB In our previous article [D. H. Huang, A. Singh, and D. A. Cardimona, J. Appl. Phys. 87, 2427 (2000)], we explained the experimentally observed zero-bias residual tunneling current [A. Singh and D. A. Cardimona, Opt. Eng. 38, 1424 (1999)] in quantum-well photodetectors biased by an ac voltage. In this article, we extend our theory to include the photoemission current and reproduce our recent findings on the dynamical drop of photoresponsivity R-ph(t) from its static value R-ph(0) in quantum-well photodetectors as a function of the chopping frequency of the incident optical flux. In this theory, we derive a dynamical equation for a nonadiabatic space-charge field E-na(t) in the presence of an applied electric field E-b(t) and an incident optical flux Phi (op)(t). From it, a compensation of the charge fluctuations in quantum wells is predicted as a result of dual tunneling and photon-assisted escaping paths. We also find a suppression of the nonadiabatic deviation of R-ph(t) from R-ph(0) due to a charge-depletion effect in the quantum wells. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, AFRL, VSSS, Kirtland AFB, NM 87117 USA. JDS Uniphase Corp, Monmouth Execut Ctr, Freehold, NJ 07728 USA. RP USAF, Res Lab, AFRL, VSSS, 3550 Aberdeen Ave SE,Bldg 426, Kirtland AFB, NM 87117 USA. EM danhong.huang@kirtland.af.mil RI Morath, Christian/B-9147-2008 OI Morath, Christian/0000-0001-5838-9301 NR 9 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 2001 VL 89 IS 8 BP 4429 EP 4437 DI 10.1063/1.1351867 PG 9 WC Physics, Applied SC Physics GA 417HB UT WOS:000167828500034 ER PT J AU Villars, P Brandenburg, K Berndt, M LeClair, S Jackson, A Pao, YH Igelnik, B Oxley, M Bakshi, B Chen, P Iwata, S AF Villars, P Brandenburg, K Berndt, M LeClair, S Jackson, A Pao, YH Igelnik, B Oxley, M Bakshi, B Chen, P Iwata, S TI Binary, ternary and quaternary compound former/nonformer prediction via Mendeleev number SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article; Proceedings Paper CT 13th InTernational Conference on Solid Compounds of Transition Elements CY APR 04-07, 2000 CL STRESA, ITALY DE materials design; neural networks; compound prediction; materials databases AB A significant breakthrough has been achieved in the design of new materials by using materials databases! semiempirical approaches and neural networks. It was found in the present work that a nonlinear expression involving one elemental property parameter can be used to predict, with an overall accuracy exceeding 99%, the occurrence of a compound for any binary, ternary or. quaternary system. This elemental property parameter, referred to as the Mendeleev number, was conceived by D.G. Pettifor in 1983 to group binary compounds by crystal structures. The immediate profit of this discovery is the obvious savings, in time and resources, relative to the investigation of yet-to-be-studied, materials systems. In the longer term the relation found here will make it possible to better define the search space for the development of new materials and encourage attempts to predict more specific information such as stoichiometries, crystal structures and physical properties. (C) 2001 Elsevier Science B.V. All rights reserved. C1 MPDS, CH-6354 Vitznau, Switzerland. Crystal Impact, Bonn, Germany. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Case Western Reserve Univ, Cleveland, OH 44106 USA. USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. Ohio State Univ, Columbus, OH 43210 USA. Wright State Univ, Fairborn, OH USA. Univ Tokyo, RACE, Tokyo, Japan. RP Villars, P (reprint author), MPDS, CH-6354 Vitznau, Switzerland. OI Bakshi, Bhavik/0000-0002-6604-8408 NR 23 TC 29 Z9 29 U1 1 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD APR 12 PY 2001 VL 317 BP 26 EP 38 DI 10.1016/S0925-8388(00)01410-9 PG 13 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 423CE UT WOS:000168157200006 ER PT J AU Arnold, ST Viggiano, AA AF Arnold, ST Viggiano, AA TI Turbulent ion flow tube study of the cluster-mediated reactions of SF6- with H2O, CH3OH, and C2H5OH from 50 to 500 torr SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID GAS-PHASE REACTION; TRAJECTORY CALCULATIONS; SULFUR-HEXAFLUORIDE; MOLECULE; WATER; PRESSURE; TEMPERATURE; PRODUCTS; VAPOR; SO3 AB Reactions of SF6- with H2O, CH3OH, and C2H5OH were studied at 298 K from 50 to 500 Torr in a newly constructed turbulent ion flow tube (TIFT). These reactions were found to be cluster-mediated reactions, where the reactants are in equilibrium with a stable association complex and then products are formed via a bimolecular reaction of the complex with a second neutral reactant. By use of known equilibrium constants, rate constants were derived for the reaction of the complex with the second solvent molecule. The rate constants for these reactions, which are essentially pressure-independent, are 3.2 x 10(-14) cm(3) s(-1), 1.8 x 10(-13) cm(3) s(-1) and 2.2 x 10(-13) cm(3) s(-1) for H2O, CH3OH, and C2H5OH, respectively. Primary product ions for the H2O reaction include SOE4- and F-(HF)(2), and primary products for the CH3OH and C2H5OH reactions include F-(HF)(ROH) and F-(HF)(2). The observed ions are frequently solvated. The product distributions for the alcohol reactions show pressure dependencies from 50 to 500 Torr. These results have implications for the modeling of low-temperature corona or glow-type discharges, as well as for the use of SF6- as a chemical ionization mass spectrometry agent in humid environments. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Arnold, ST (reprint author), USAF, Res Lab, Space Vehicles Directorate, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 22 TC 23 Z9 24 U1 3 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 APR 12 PY 2001 VL 105 IS 14 BP 3527 EP 3531 DI 10.1021/jp003967y PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 423LN UT WOS:000168177900014 ER PT J AU Yoo, HY Boatz, JA Helms, V McCammon, JA Langhoff, PW AF Yoo, HY Boatz, JA Helms, V McCammon, JA Langhoff, PW TI Chromophore protonation states and the proton shuttle mechanism in green fluorescent protein: Inferences drawn from ab initio theoretical studies of chemical structures and vibrational spectra SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID PHOTOACTIVE YELLOW PROTEIN; ELECTRONIC-STRUCTURE; CRYSTAL-STRUCTURE; SPECTROSCOPY; DYNAMICS; BEHAVIOR; LIGHT; GFP AB Assignments are provided of prominent features in the recently measured Fourier transform infrared (FTIR) difference spect ra of green fluorescent and photoactive yellow proteins (GFP, PYP) employing ab initio calculations of the ground electronic state structures and vibrational spectra of their chromophores in selected protonation states. Particular attention is addressed to inferring the protonation states of wild-type GFP chromophore and to reconciling the measured FTIR difference spectrum with a proposed proton shuttle mechanism in which protonated and deprotonated forms of the chromophore are paired with corresponding charge states of a Glu222 residue shuttle terminus. The calculated GFP IR difference spectrum obtained from the neutral-anionic pair of chromophores is found to be in general accord with the FTIR measurements on wild-type GFP in its protonated and deprotonated farms, whereas the spectrum obtained from the zwitterionic-cationic pair of chromophores provides a less satisfactory simulation of the data. The apparent absence of a carbonyl band in the measured GFP FTIR difference spectrum, a feature expected upon protonation of the carboxylic Glu222 residue, is reconciled by the presence of a carbonyl mode in the imidazole ring of the neutral chromophore which partially obscures the anticipated R-COOH Glu222 feature in the calculated spectrum. By contrast, the corresponding carbonyl mode in the PYP chromophore is predicted to be significantly weaker and at lower frequency than in GFP, accounting in part for the presence of an unobscured prominent R-COOH Glu46. residue carbonyl mode in the measured PYP FTIR difference spectrum. Accordingly, the present ab initio theoretical study supports the predominance of neutral and anionic forms of wild-type GFP chromophore, and it argueably reconciles the available FTIR data with a probable Glu222 terminus of the proposed proton shuttle mechanism in the protein. Additional experimental studies of IR and Raman difference spectra in GFP and PYP, including particularly isotopic substitutions, are suggested to complement additional theoretical studies in progress. C1 Univ Calif San Diego, San Diego Supercomp Ctr, La Jolla, CA 92093 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92619 USA. USAF, Res Lab, PRS, AFRL, Edwards AFB, CA 93524 USA. Max Planck Inst Biophys, D-60596 Frankfurt, Germany. Univ Calif San Diego, Dept Chem & Biochem, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Pharmacol, La Jolla, CA 92093 USA. Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. RP Langhoff, PW (reprint author), Univ Calif San Diego, San Diego Supercomp Ctr, 9500 Gilman Dr, La Jolla, CA 92093 USA. OI Helms, Volkhard/0000-0002-2180-9154 NR 39 TC 24 Z9 24 U1 2 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 12 PY 2001 VL 105 IS 14 BP 2850 EP 2857 DI 10.1021/jp003683d PG 8 WC Chemistry, Physical SC Chemistry GA 423LQ UT WOS:000168178100027 ER PT J AU Kirkpatrick, SM Naik, RR Stone, MO AF Kirkpatrick, SM Naik, RR Stone, MO TI Nonlinear saturation and determination of the two-photon absorption cross section of green fluorescent protein SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID 2-PHOTON; PHOTOPOLYMERIZATION; MICROFABRICATION; MICROSCOPY; EXCITATION; DYNAMICS; BEAM AB Two-photon absorption is a nonlinear phenomenon that is observed in materials irradiated with the combined energy of two photons, which matches the transition energy between the ground state and the excited state. Molecules exhibiting strong two-photon absorption have great potential in a wide range of applications such as three-dimensional fluorescence imaging, optical data storage, and microfabrication.(9.6) Green fluorescent protein (GFP) can be excited by a two-photon mechanism and exhibits a nonlinear behavior of the effective two-photon absorption coefficient. Here we present the quantitative determination of the two-photon absorption saturation of GFP in both a homogeneously broadened and inhomogeneously broadened system. We further show that, dominated by strong nonlinear saturation, GFP has a large intrinsic two-photon absorption cross section (sigma (TPA)) value that is several orders of magnitude larger than that of chemically synthesized compounds. C1 USAF, MLPJ, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Tech Management Concepts Inc, Beavercreek, OH 44543 USA. RP Stone, MO (reprint author), USAF, MLPJ, Mat & Mfg Directorate, 3005 P St,Bldg 651, Wright Patterson AFB, OH 45433 USA. NR 19 TC 39 Z9 39 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 12 PY 2001 VL 105 IS 14 BP 2867 EP 2873 DI 10.1021/jp0041609 PG 7 WC Chemistry, Physical SC Chemistry GA 423LQ UT WOS:000168178100030 ER PT J AU Khoury, J Gianino, PD Woods, CL AF Khoury, J Gianino, PD Woods, CL TI Speckle velocimetry by means of holographic time-integrative correlation SO APPLIED OPTICS LA English DT Article ID PATTERN INTERFEROMETER; DIFFUSE OBJECT; DISPLACEMENT; DETECTOR; VELOCITY; MOTION; LIGHT AB We develop the theory of the speckle velocimeter that is based on use of a photorefractive real-time hologram in four-wave mixing as a time-integrative correlator. The theory of the speckle velocimeter has been developed for the time correlation between the far-field spectrum of light scattered from the diffuser and the reference wave that, is Doppler shifted. Our theoretical derivation shows that it is possible to extract the velocity with minor processing of the output correlation, (C) 2001 Optical Society of America. C1 Lartec Inc, Sudbury, MA 01776 USA. SNHC, USAF, Res Lab, Bedford, MA 01731 USA. RP Khoury, J (reprint author), Lartec Inc, Sudbury, MA 01776 USA. EM peter.gianino@hanscom.af.mil NR 21 TC 3 Z9 3 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD APR 10 PY 2001 VL 40 IS 11 BP 1814 EP 1818 DI 10.1364/AO.40.001814 PG 5 WC Optics SC Optics GA 420NE UT WOS:000168010400008 PM 18357180 ER PT J AU Fitzgerald, PJ Takagi, A Moore, P Hayase, M Kolodgie, FD Corl, D Nassi, M Virmani, R Yock, P AF Fitzgerald, PJ Takagi, A Moore, P Hayase, M Kolodgie, FD Corl, D Nassi, M Virmani, R Yock, P TI Intravascular sonotherapy decreases neointimal hyperplasia after stent implantation in swine SO CIRCULATION LA English DT Article DE ultrasonics; stents; restenosis; hyperplasia ID CELLS IN-VITRO; ARTERY DISEASE; ULTRASOUND; ANGIOPLASTY; RESTENOSIS; RADIATION; THROMBI; INVITRO AB Background-Intimal hyperplasia and subsequent in-stent restenosis remain a major limitation after stent implantation. In vitro cell culture studies show that low-frequency, noncavitational ultrasound energy may impact smooth muscle cell proliferation. Accordingly, we assessed the efficacy of intravascular sonotherapy treatment on intimal hyperplasia in a swine stent model, Methods and Results-After balloon injury, biliary stents (Johnson & Johnson) were implanted in the femoral arteries of 14 swine. A total of 48 stented sites were randomized to sonotherapy or sham treatment using a custom-built, X-French catheter intravascular sonotherapy system (URX, PharmaSonics Inc). After stent deployment, ultrasound energy (700 KHz) was applied to the treatment group for lip to 5 minutes. Smooth muscle cell proliferation was assessed using bromodeoxyuridine histology preparation (BrdU) at 7 days in 28 stented sites. At 28 days, the neointimal thickness and the ratio of neointimal/stent area (percent stenosis) was calculated by histomorphometric quantification in 20 stented sites. At 7 days, percent of BrdU staining was significantly reduced in the sonotherapy group compared with the sham group (24.1 +/-7.0% versus 31.2 +/-3.0%, P<0.05). At 28 days, percent stenosis was significantly less in the sonotherapy group than in the sham group (3624% versus 44 +/- 27%, P<0.05), and the mean neointimal thickness in the sonotherapy group was less than in the sham group (417461 mum versus 643 +/- 869 mum, P=0.06). Conclusions-In this swine peripheral model, intravascular sonotherapy seemed to decelerate cellular proliferation and decrease in-stent hyperplasia. Therefore, intravascular sonotherapy may be an effective form of nonionizing energy to reduce in-stent restenosis. C1 Stanford Univ, Med Ctr, Ctr Res Cardiovasc Intervent, Div Cardiovasc Med, Stanford, CA 94305 USA. PharmaSon Inc, Sunnyvale, CA USA. USAF, Inst Pathol, Washington, DC 20330 USA. RP Fitzgerald, PJ (reprint author), Stanford Univ, Med Ctr, Ctr Res Cardiovasc Intervent, Div Cardiovasc Med, 300 Pasteur Dr,H3554, Stanford, CA 94305 USA. NR 20 TC 34 Z9 45 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD APR 10 PY 2001 VL 103 IS 14 BP 1828 EP 1831 PG 4 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 422MK UT WOS:000168122300010 PM 11294798 ER PT J AU Mohseni, H Razeghi, M Brown, GJ Park, YS AF Mohseni, H Razeghi, M Brown, GJ Park, YS TI High-performance InAs/GaSb superlattice photodiodes for the very long wavelength infrared range SO APPLIED PHYSICS LETTERS LA English DT Article ID INAS/GA1-XINXSB SUPERLATTICE; DETECTORS; GROWTH; PHOTOCONDUCTORS AB We report on the demonstration of high-performance p-i-n photodiodes based on type-II InAs/GaSb superlattices with 50% cut-off wavelength lambda (c)=16 mum operating at 80 K. Material is grown by molecular beam epitaxy on GaSb substrates with excellent crystal quality as evidenced by x-ray diffraction and atomic force microscopy. The processed devices show a current responsivity of 3.5 A/W at 80 K leading to a detectivity of similar to1.51x10(10) cmHz(1/2)/W. The quantum efficiency of these devices is about 35% which is comparable to HgCdTe detectors with a similar active layer thickness. (C) 2001 American Institute of Physics. C1 Northwestern Univ, Dept Elect & Comp Engn, Ctr Quantum Devices, Evanston, IL 60208 USA. USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Off Naval Res, Arlington, VA 22217 USA. RP Mohseni, H (reprint author), Northwestern Univ, Dept Elect & Comp Engn, Ctr Quantum Devices, Evanston, IL 60208 USA. RI Mohseni, Hooman/B-7253-2009; Razeghi, Manijeh/B-7265-2009 NR 16 TC 74 Z9 76 U1 1 U2 16 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 9 PY 2001 VL 78 IS 15 BP 2107 EP 2109 DI 10.1063/1.1362179 PG 3 WC Physics, Applied SC Physics GA 418GA UT WOS:000167881500005 ER PT J AU Fang, ZQ Look, DC Visconti, P Wang, DF Lu, CZ Yun, F Morkoc, H Park, SS Lee, KY AF Fang, ZQ Look, DC Visconti, P Wang, DF Lu, CZ Yun, F Morkoc, H Park, SS Lee, KY TI Deep centers in a free-standing GaN layer SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTRON AB Schottky barrier diodes, on both Ga and N faces of a similar to 300-mum-thick free-standing GaN layer, grown by hydride vapor phase epitaxy (HVPE) on Al2O3 followed by laser separation, were studied by capacitance-voltage and deep level transient spectroscopy (DLTS) measurements. From a 1/C-2 vs V analysis, the barrier heights of Ni/Au Schottky contacts were determined to be different for the two polar faces: 1.27 eV for the Ga face, and 0.75 eV for the N face. In addition to the four common DLTS traps observed previously in other epitaxial GaN including HVPE-grown GaN a new trap B-' with activation energy E-T=0.53 eV was found in the Ga-face sample. Also, trap E-1 (E-T=0.18 eV), believed to be related to the N vacancy, was found in the N-face sample, and trap C (E-T=0.35 eV) was in the Ga-face sample. Trap C may have arisen from reactive-ion-etching damage. (C) 2001 American Institute of Physics. C1 Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Virginia Commonwealth Univ, Dept Elect Engn, Richmond, VA 23284 USA. Virginia Commonwealth Univ, Dept Phys, Richmond, VA 23284 USA. Samsung Adv Inst Technol, Suwon 440600, South Korea. RP Fang, ZQ (reprint author), Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. RI VISCONTI, PAOLO/L-7214-2015 OI VISCONTI, PAOLO/0000-0002-4058-4042 NR 12 TC 69 Z9 71 U1 0 U2 19 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 9 PY 2001 VL 78 IS 15 BP 2178 EP 2180 DI 10.1063/1.1361273 PG 3 WC Physics, Applied SC Physics GA 418GA UT WOS:000167881500029 ER PT J AU Midey, AJ Viggiano, AA AF Midey, AJ Viggiano, AA TI Mobilities of NH4+(NH3)(n) clusters in helium from 100 K to 298 K SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID NU(3) INFRARED-SPECTRUM; KINETIC-ENERGY; IONS; TEMPERATURE; COMPLEX; GAS AB A variable temperature-selected ion flow drift tube (VT-SIFDT) has been used to measure the mobilities of NH4+(NH3)(n) clusters drifting in He. The mobilities have been measured for n=0-2 at 298 K, n=0-3 at 200 K, and n=0-5 at 100 K, marking the first mobilities experiments for these clusters below room temperature. The reduced mobilities measured at 298 K are compared to the previous SIFDT results of Krishnamurthy [J. Chem. Phys. 106, 530 (1997)] for n=0-2. While the current results compare quite favorably for n=0-2, there is a discrepancy for n=3 which is addressed by current 100 K and 200 K data where these species are thermally stable. The trends in the mobilities from 100 K to 298 K as a function of E/N and effective temperature reveal that the repulsive part of the He-NH4+(NH3)(n) interaction potential is sampled predominantly for n=1-5. However, the attractive part of the potential is accessed at the lowest temperatures for He-NH4+. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Viggiano, AA (reprint author), USAF, Res Lab, Space Vehicles Directorate, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 14 TC 3 Z9 3 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 8 PY 2001 VL 114 IS 14 BP 6072 EP 6076 DI 10.1063/1.1354136 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 415WA UT WOS:000167745500013 ER PT J AU Dotan, I Viggiano, AA AF Dotan, I Viggiano, AA TI Kinetics of the reaction of O-2(+) with CH4 from 500 to 1400 K: A case for state specific chemistry SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ION-MOLECULE REACTIONS; LASER-INDUCED FLUORESCENCE; RATE CONSTANTS; INTERNAL ENERGY; CH3O2+ PRODUCT; FLOW TUBE; TEMPERATURE; O-2+; O2+; DEPENDENCE AB Rate constants and branching ratios have been measured for the reaction of O-2(+) with CH4 over the temperature range from 500 to 1400 K. The rate constants increase dramatically over this temperature range, in good agreement with a previous study from our laboratory. A complex chemistry was found. The main product at low temperature, CH2O2H+, disappears almost completely at high temperature, in part due to thermal dissociation. The main products at high temperature are CH4+ and HCO+; the latter ion has not been observed previously. Also prominent at high temperature are H3O+ and CH3+. A small amount of CH3O+ is observed at all temperatures. H2O+ is observed in small quantities at high temperature. Branching ratios for the reaction of O-2(+) with CD4 are also reported, confirming the ion assignments. Comparison to drift tube and beam results indicates that vibrational excitation of the CH4 promotes several of these channels more than other forms of energy. Channels which proceed through the t-CH3OOH+ (2)A(') intermediate (described in the accompanying paper) are probably not strongly dependent on the form of energy, although uncertainties prevent a definitive conclusion. The charge-transfer channel and the channels requiring substantial rearrangement are greatly enhanced by vibrational excitation. Thus, specific channels do appear to be governed by vibrational excitation. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Space Vehicles Directorate, Bedford, MA 01731 USA. Open Univ Israel, Tel Aviv, Israel. RP Viggiano, AA (reprint author), USAF, Res Lab, Space Vehicles Directorate, 29 Randolph Rd, Bedford, MA 01731 USA. NR 38 TC 8 Z9 8 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 8 PY 2001 VL 114 IS 14 BP 6112 EP 6118 DI 10.1063/1.1352033 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 415WA UT WOS:000167745500018 ER PT J AU Baek, JB Mather, PT Tan, LS AF Baek, JB Mather, PT Tan, LS TI Synthesis and chain-end functionalization of a new hyperbranched poly(arylene-ethere-ketone-imide). SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Dayton, Res Inst, Polymer Grp, Dayton, OH 45469 USA. Univ Connecticut, Inst Mat Sci, Storrs, CT 06269 USA. USAF, Res Lab, AFRL MLBP, Polymer Branch, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 407-PMSE BP U419 EP U419 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824802537 ER PT J AU Baek, JB Ferguson, JB Mather, PT Tan, LS AF Baek, JB Ferguson, JB Mather, PT Tan, LS TI Hyperbranched aromatic polyamides containing ether and quinoxaline units and their blends with BMI. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Dayton, Res Inst, Polymer Grp, Dayton, OH 45469 USA. USAF, Res Lab, Polymer Branch, AFRL,MLBP, Washington, DC 20330 USA. Univ Connecticut, Inst Mat Sci, Polymer Program, Storrs, CT 06269 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 397-PMSE BP U418 EP U418 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824802527 ER PT J AU Blanski, RL Phillips, SH Lee, A AF Blanski, RL Phillips, SH Lee, A TI Preparation and properties of polyhedral oligosilsesquioxanes/polymer blends. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, PRSM, Edwards AFB, CA 93524 USA. Michigan State Univ, Dept Mat Sci & Mech, E Lansing, MI 48824 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 266-POLY BP U334 EP U334 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801987 ER PT J AU Brott, LL Naik, RR Kirkpatrick, SM Pikas, DJ Stone, MO AF Brott, LL Naik, RR Kirkpatrick, SM Pikas, DJ Stone, MO TI Near-IR two-photon induced polymerizations using either benzophenone or thioxanthone-based photoinitiators. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Air Force Res Lab, MLPJ, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 342-POLY BP U345 EP U345 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824802063 ER PT J AU Burk, S Johnson, JEB Balaich, GJ Chamberlin, R Abney, K AF Burk, S Johnson, JEB Balaich, GJ Chamberlin, R Abney, K TI Synthesis and ring opening metathesis polymerization of norbornene functionalized cobalt dicarbollide compounds. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, USAF Acad, CO 80840 USA. Los Alamos Natl Lab, Nucl & Radiochem Grp, Los Alamos, NM USA. EM gary.balaich@usafa.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 407-CHED BP U164 EP U164 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824701375 ER PT J AU Cunningham, MZ Gold, L Golden, MC AF Cunningham, MZ Gold, L Golden, MC TI PhotoSELEX employing 5-(4-benzoylphenyl)-DUTP and 5-(4-azidophenyl)-DUTP for the BFGF target. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, USAF Acad, CO 80840 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 625-CHED BP U195 EP U195 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824701592 ER PT J AU Curliss, D Chen, CG Rice, BP AF Curliss, D Chen, CG Rice, BP TI High performance fiber reinforced composites with polymer-silicate nanocomposite matrix. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM david.curliss@afrl.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 99-IEC BP U569 EP U569 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703709 ER PT J AU Dang, TD Johnson, JA Arnold, FE AF Dang, TD Johnson, JA Arnold, FE TI Post-functionalized 1H-pyrazole based benzoxazoles for high performance coatings applications. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 AFRL, MLBP, Mat & Mfg Technol Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 321-PMSE BP U406 EP U407 PN 2 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824802451 ER PT J AU Dang, TD Venkatasubramanian, N Baum, EW Feld, WA Arnold, FE AF Dang, TD Venkatasubramanian, N Baum, EW Feld, WA Arnold, FE TI Aromatic benzobisazole polymers containing 4-hydroxypyridine-2,6-diyl unit. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 AFRL, MLBP, Mat & Mfg Technol Directorate, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. Wright State Univ, Dept Chem, Dayton, OH 45435 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 260-PMSE BP U398 EP U398 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824802390 ER PT J AU Day, PN Nguyen, KA Pachter, R AF Day, PN Nguyen, KA Pachter, R TI Prediction of two-photon absorption using time-dependent density functional theory. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM paul.day@afrl.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 118-IEC BP U572 EP U572 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703728 ER PT J AU Fong, H Vaia, RA Sanders, JH Lincoln, DM John, PJ Vreugdenhil, AJ Bultman, J Cerbus, CA Jeon, HG AF Fong, H Vaia, RA Sanders, JH Lincoln, DM John, PJ Vreugdenhil, AJ Bultman, J Cerbus, CA Jeon, HG TI Formation of self generating, inorganic passivation layer on Nylon 6/layered silicate nanocomposite. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Nonmetall Mat Div, Polymer Branch, Wright Patterson AFB, OH 45433 USA. AFRL, MLBP, Mat & Mfg Technol Directorate, Wright Patterson AFB, OH USA. USAF, Mat & Mfg Directorate, Washington, DC 20330 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. MLBP, AFRL, Systran Corp, Wright Patterson AFB, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 239-POLY BP U330 EP U330 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801960 ER PT J AU Gilman, JW VanderHart, D Asano, A Sutto, TE Awad, W Trulove, PC DeLong, H Davis, RD AF Gilman, JW VanderHart, D Asano, A Sutto, TE Awad, W Trulove, PC DeLong, H Davis, RD TI Recent advances in characterization and processing of flame retardant polymer nanocomposites. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Natl Inst Stand & Technol, Div Fire Sci, Mat Fire Res Grp, Gaithersburg, MD 20899 USA. NIST, Div Polymers, Gaithersburg, MD 20899 USA. USN, Res Lab, Div Chem, Washington, DC 20375 USA. USAF, Off Sci Res, Washington, DC USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. EM jeffrey.gilman@nist.gov NR 0 TC 0 Z9 0 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 291-IEC BP U612 EP U612 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703904 ER PT J AU Haddad, TS Lee, A Phillips, SH AF Haddad, TS Lee, A Phillips, SH TI Poly(dimethylsiloxanes) modified with inorganic polyhedra. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 ERC, Edwards AFB, CA 93524 USA. USAF, Res Lab, Edwards AFB, CA 93524 USA. Michigan State Univ, Dept Mat Sci & Mech, E Lansing, MI 48824 USA. USAF, Res Lab, AFRL, PRSM, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 159-POLY BP U317 EP U317 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801881 ER PT J AU Henley, MV Bradley, WR Wyatt, SE Graziano, GM Wells, JR AF Henley, MV Bradley, WR Wyatt, SE Graziano, GM Wells, JR TI Gas-phase reactions of cyclohexanol with the hydroxyl radical. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Air Expedit Forces Technol Div, MLQL, Tyndall AFB, FL 32403 USA. NIOSH, Resp Branch, Cincinnati, OH USA. EM mike.henley@tyndall.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 260-ENVR BP U486 EP U486 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703277 ER PT J AU Hicks, B Grabow, W Gardner, KA AF Hicks, B Grabow, W Gardner, KA TI EPR binding studies of a spin-labelled cisplatin analogue. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, USAF Acad, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 590-CHED BP U189 EP U189 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824701557 ER PT J AU Hicks, BW AF Hicks, BW TI Research projects to prepare undergraduate biochemistry majors for graduate-level research. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Academy, CO 80840 USA. EM barry.hicks@usafa.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 1078-CHED BP U265 EP U265 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824702046 ER PT J AU Karna, SP Pati, R AF Karna, SP Pati, R TI Molecular electronics: A quantum mechanical approach. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Air Force Res Lab, Space Vehicles Directorate, VSSE, Kirtland AFB, NM USA. Univ New Mexico, Ctr High Performance Comp, Albuquerque, NM 87131 USA. EM karnas@plk.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 354-IEC BP U622 EP U622 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703962 ER PT J AU Langhoff, PW Boatz, JA Hinde, RJ Sheehy, JA AF Langhoff, PW Boatz, JA Hinde, RJ Sheehy, JA TI Spectral theory of chemical bonding: New methods for calculating potential energy surfaces. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. USAF, Res Lab, AFRL, PRSP, Washington, DC 20330 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 395-PHYS BP U293 EP U293 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801716 ER PT J AU Langhoff, PW Yoo, HY Boatz, JA Helms, V McCammon, JA AF Langhoff, PW Yoo, HY Boatz, JA Helms, V McCammon, JA TI Chromophore charge states and the proton shuttle mechanism in green fluorescent protein: Inferences drawn from calculated vibronic spectra. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. USAF, Res Lab, AFRL, PRS, Washington, DC 20330 USA. Max Planck Inst Biophys, D-6000 Frankfurt, Germany. Univ Calif San Diego, Dept Chem & Biochem, San Diego, CA 92103 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 341-PHYS BP U285 EP U285 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801663 ER PT J AU Langhoff, PW Arce, JC Sheehy, JA Hemmers, OA Wang, H Focke, P Sellin, IA Lindle, DW AF Langhoff, PW Arce, JC Sheehy, JA Hemmers, OA Wang, H Focke, P Sellin, IA Lindle, DW TI On the angular distributions of electrons photoejected from fixed-in-space and randomly oriented molecules. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. Univ Valle, Dept Quim, Cali, Colombia. USAF, Res Lab, PRS, Washington, DC USA. Univ Nevada, Dept Chem, Reno, NV 89557 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 22-PHYS BP U231 EP U231 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801349 ER PT J AU McGill, RJ Koch, TH Golden, MC AF McGill, RJ Koch, TH Golden, MC TI Thermoselex employing 5-modified dUTPs for the bFGF target. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. EM robert.mcgill@usafa.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 651-CHED BP U199 EP U199 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824701617 ER PT J AU Miller, JS Dressler, RA Chiu, YH Levandier, DJ AF Miller, JS Dressler, RA Chiu, YH Levandier, DJ TI Vibrational effects in collision-induced dissociation dynamics of diatomic ions. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MI USA. Boston Coll, Inst Sci Res, Chestnut Hill, MA 02167 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 226-PHYS BP U268 EP U268 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801548 ER PT J AU Moore, BM Haddad, TS Phillips, S AF Moore, BM Haddad, TS Phillips, S TI Synthesis and characterization of a new (tetrasilanol)cyclosiloxane. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, ERC Corp, Edwards AFB, CA 93536 USA. USAF, Res Lab, Prop Directorate, Edwards AFB, CA 93536 USA. AFRL, PRSM, ERC, Edwards AFB, CA 93536 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 278-POLY BP U336 EP U336 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801999 ER PT J AU Morgan, ME Bales, JRT Rueter, BA AF Morgan, ME Bales, JRT Rueter, BA TI Controlling the LabWorks interface with palm PCs. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. EM matt.morgan@usafa.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 687-CHED BP U204 EP U204 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824701653 ER PT J AU Nguyen, KA Day, PN Kennel, J Pachter, R AF Nguyen, KA Day, PN Kennel, J Pachter, R TI On the prediction of nonlinear absorption for two-photon and reverse saturable absorption dyes using time-dependent density functional theory. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Laser Hardened Mat Branch, MLPJ, Wright Patterson AFB, OH 45433 USA. EM kiet.nguyen@afrl.af.mil; daypaul@biotech.ml.wpafb.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 132-COMP BP U411 EP U411 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824702896 ER PT J AU Nguyen, KA Pachter, R AF Nguyen, KA Pachter, R TI Ground and excited states of zinc complexes of porphyrin, tetraazaporphyrin, tetrabenzporphyrin, and phthalocyanine: A density functional theory study. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, MLPJ, Wright Patterson AFB, OH 45433 USA. EM kiet.nguyen@afrl.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 133-COMP BP U411 EP U411 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824702897 ER PT J AU Park, SY Zhang, T Interrante, LV Farmer, BL AF Park, SY Zhang, T Interrante, LV Farmer, BL TI Structures of side chain liquid crystalline poly(silylenemethylene)s. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Rensselaer Polytech Inst, Dept Chem, Troy, NY USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 275-POLY BP U335 EP U335 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801996 ER PT J AU Phillips, SH Blanski, RL Haddad, TS Steve, S Viers, B Feher, FJ Lee, A Gonzalez, R AF Phillips, SH Blanski, RL Haddad, TS Steve, S Viers, B Feher, FJ Lee, A Gonzalez, R TI New multi-functional materials using versatile hybrid (inorganic/organic) POSS nanotechnology. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, PRSM, Edwards AFB, CA 93542 USA. USAF, Res Lab, PRSM, ERC, Edwards AFB, CA 93542 USA. Michigan State Univ, Dept Mat Sci & Mech, E Lansing, MI 48824 USA. EM shawn.phillips@edwards.af.mil NR 0 TC 0 Z9 0 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 287-IEC BP U611 EP U611 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703900 ER PT J AU Saba, CS Forster, NH AF Saba, CS Forster, NH TI Reactions of aromatic phosphate esters with Fe, Cu and their oxides. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. AFRL, Propuls Directorate, Wright Patterson AFB, OH USA. EM costandy.saba@wpafb.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 407-COLL BP U370 EP U370 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824702653 ER PT J AU Sankaran, B Vaia, RA Tan, LS AF Sankaran, B Vaia, RA Tan, LS TI Thiophene-based branched conjugated polymers. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Universal Technol Corp, Beavercreek, OH 45432 USA. USAF, Res Lab, AFRL MLBP, Polymer Branch, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 112-POLY BP U310 EP U310 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801834 ER PT J AU Sinsawat, A Putthanarat, S Zarkoob, S Magoshi, Y Magoshi, J Pachter, R Stone, MO Eby, RK AF Sinsawat, A Putthanarat, S Zarkoob, S Magoshi, Y Magoshi, J Pachter, R Stone, MO Eby, RK TI Crystal modulus of silk. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Akron, Dept Polymer Sci, Akron, OH 44325 USA. USAF, Res Lab, Mat & Mfg Directorate, Washington, DC 20330 USA. WPAFB, MLPJ, Wright Patterson AFB, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 152-POLY BP U316 EP U316 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824801874 ER PT J AU Sowards, LA Whitlock, PW Brott, LL Naik, RR Stone, MO AF Sowards, LA Whitlock, PW Brott, LL Naik, RR Stone, MO TI Ordered silica nanostructure created by reaction of tetrahydroxysilane solution with peptide isolated from the diatom C-fusiformis. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 AFRL, MLPJ, Biotechnol Grp, Wright Patterson AFB, OH USA. Univ Cincinnati, Polymer Res Grp, Cincinnati, OH 45221 USA. Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH USA. Air Force Res Labs, MLPJ, Biotechnol Grp, Wright Patterson AFB, OH USA. EM laura.sowards@afrl.af.mil NR 0 TC 1 Z9 1 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 232-BIOT BP U145 EP U145 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824700704 ER PT J AU Spencer, K Utermoehlen, CM Killpack, MO AF Spencer, K Utermoehlen, CM Killpack, MO TI Kinetic study of esterification reactions using Horizontal Attenuated Total Reflectance. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 227-CHED BP U139 EP U139 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824701196 ER PT J AU Trohalaki, S Pachter, R AF Trohalaki, S Pachter, R TI Predictive toxicology using quantum qsar descriptors from excited states. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM Steven.Trohalaki@wpafb.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 147-COMP BP U413 EP U413 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824702911 ER PT J AU Vaia, RA AF Vaia, RA TI Nanostructured materials for aerospace: Opportunities and issues. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM richard.vaia@afrl.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 290-IEC BP U612 EP U612 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703903 ER PT J AU Venkatasubramanian, N Dang, TD Vance, TA Arnold, FE AF Venkatasubramanian, N Dang, TD Vance, TA Arnold, FE TI Rigid-chain benzobisazole polymers with two sulfonic acid pendants. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. AFRL, MLBP, Mat & Mfg Technol Directorate, Wright Patterson AFB, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 330-PMSE BP U408 EP U408 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824802460 ER PT J AU Wang, ZQ Pachter, R Adkim, B Blaudeu, J AF Wang, ZQ Pachter, R Adkim, B Blaudeu, J TI Structural and mechanical properties of single wall carbon nanotubes: A density functional theory study. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Air Force Res Lab, MLPJ, Wright Patterson AFB, OH 45433 USA. EM wangz@biotech.ml.wpafb.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 356-IEC BP U622 EP U622 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703964 ER PT J AU Whitlock, PW Clarson, SJ Brott, LL Naik, RR Stone, MO AF Whitlock, PW Clarson, SJ Brott, LL Naik, RR Stone, MO TI Silicon biocatalysis. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Univ Cincinnati, Air Force Res Labs, Mat & Mfg Directorate, Dept Mat Sci & Engn, Cincinnati, OH 45221 USA. USAF, Res Labs, Mfg & Mat Directorate, Wright Patterson AFB, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 389-POLY BP U352 EP U352 PN 2 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PJ UT WOS:000168824802110 ER PT J AU Whitlock, PW Brott, LL Clarson, SJ Naik, RR Stone, MO AF Whitlock, PW Brott, LL Clarson, SJ Naik, RR Stone, MO TI Biocatalysis of silica nanostructures. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 Polymer Res Grp, Cincinnati, OH 45221 USA. Univ Cincinnati, Mat & Mfg Directorate, Cincinnati, OH 45221 USA. USAF, Res Lab, Coll Engn, Cincinnati, OH 45221 USA. AFRL MLPJ, Cincinnati, OH 45221 USA. USAF, Res Lab, Mat & Mfg Directorate, Washington, DC 20330 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. EM whitlopw@email.uc.edu NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 321-IEC BP U617 EP U617 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703934 ER PT J AU Wilkes, JS AF Wilkes, JS TI Ionic liquids in perspective: The past with an eye toward the industrial future. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF Acad, Dept Chem, Colorado Springs, CO 80840 USA. EM john.wilkes@usafa.af.mil NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 246-IEC BP U591 EP U591 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703852 ER PT J AU Wilson, WH Kramer, MP Armstrong, RW AF Wilson, WH Kramer, MP Armstrong, RW TI Air force research in nanoenergetics: Potential advantages and challenges. SO ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY LA English DT Meeting Abstract C1 USAF, Res Lab, AFRL MNME, Munit Directorate,Energet Mat Branch, Eglin AFB, FL 32542 USA. EM wilsonwh@eglin.af.mil NR 0 TC 4 Z9 4 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0065-7727 J9 ABSTR PAP AM CHEM S JI Abstr. Pap. Am. Chem. Soc. PD APR 1 PY 2001 VL 221 MA 264-IEC BP U608 EP U608 PN 1 PG 1 WC Chemistry, Multidisciplinary SC Chemistry GA 434PH UT WOS:000168824703877 ER PT J AU Gooden, A AF Gooden, A TI Out of Africa SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Editorial Material DE head trauma; aeromedical evacuation RP Gooden, A (reprint author), USAF, NC, 107 Thornell St, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD APR PY 2001 VL 72 IS 4 BP 405 EP 406 PG 2 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 415HM UT WOS:000167715400013 PM 11318023 ER PT J AU Schwartz, Z Lohmann, CH Sisk, M Cochran, DL Sylvia, VL Simpson, J Dean, DD Boyan, BD AF Schwartz, Z Lohmann, CH Sisk, M Cochran, DL Sylvia, VL Simpson, J Dean, DD Boyan, BD TI Local factor production by MG63 osteoblast-like cells in response to surface roughness and 1,25-(OH)(2)D-3 is mediated via protein kinase C- and protein kinase A-dependent pathways SO BIOMATERIALS LA English DT Article DE titanium surface roughness; 1,25-(OH)(2)D-3; TGF-beta 1; PGE(2); MG63 cells ID GROWTH-PLATE CHONDROCYTES; ACID-ETCHED SURFACE; 1,25-DIHYDROXYVITAMIN D-3; MEMBRANE-RECEPTOR; TITANIUM IMPLANTS; ACTIVATION; DIFFERENTIATION; MECHANISMS; MG-63; MATRIX AB Titanium (Ti) surface roughness affects bone formation in vivo and osteoblast attachment, proliferation and differentiation in vitro. MG63 cells exhibit decreased proliferation and increased differentiation when cultured on rough Ti surfaces (R-a > 2 mum) and response to 1,25-(OH)(2)D-3 is enhanced, resulting in synergistic increases in TGF-beta1 and PGE(2). To examine the hypothesis that surface roughness and 1,25-(OH)(2)D-3 exert their effects on local factor production through independent, but convergent, signaling pathways, MG63 cells were cultured on tissue culture plastic or on smooth (PT, R-a = 0.60 mum) and rough (SLA, R-a = 3.97 mum; TPS, R-a = 5.21 mum) Ti disks. At confluence (5 days), cultures were treated for 24h with 10(-8)M 1 alpha ,25-(OH)(2)D-3 and active and latent TGF-beta1 in the conditioned media measured by ELISA. Cell layers were digested with plasmin and released TGF-beta1 was also measured. 1,25-(OH)(2)D-3 regulated the distribution of TGF-beta1 between the media and the matrix in a surface-dependent manner; the effect was greatest in the matrix of cells cultured on SLA and TPS. Inhibition of PKA with H8 for the last 24h of culture increased PGE(2) on SLA and TPS, but when present throughout the entire culture period H8 caused an increase in PGE(2) on all surfaces. 1,25-(OH)(2)D-3 reduced the effect of H8 on PGE(2) production in cultures treated for 24 h. H8 had no effect on TGF-beta1 in the media by itself but caused a complete inhibition of the 1,25-(OH)(2)D-3 dependent increase. Inhibition of PKC with chelerythrine increased PGE(2) in a surface-dependent manner and 1,25-(OH)(2)D-3 reduced the effect of the PKC inhibitor. Chelerythrine also increased TGF-beta1 but the effect was not surface dependent; however, 1,25-(OH)(2)D-3 reduced the effects of chelerythrine with the greatest effects on the smooth surface. Thus, the distribution of TGF-beta1 between the media and the matrix is regulated by 1,25-(OH)(2)D-3 in a surface-dependent manner. Surface roughness exerts its effects on TGF-beta1 production via PKC but not PKA. The effect of 1,25-(OH)(2)D-3 on TGF-beta1 production is not via PKC. PKA is involved in the surface-dependent regulation of PGE(2) but not in the regulation of PGE(2) by 1,25-(OH)(2)D-3 on rough surfaces. Regulation of PKC affects PGE(2) production but it is not involved in the surface roughness dependent response to 1,25-(OH)(2)D-3. These results suggest two independent but interconnected pathways are involved. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Texas, Hlth Sci Ctr, Dept Orthopaed, San Antonio, TX 78229 USA. Univ Texas, Hlth Sci Ctr, Dept Periodont, San Antonio, TX 78229 USA. Univ Texas, Hlth Sci Ctr, Dept Biochem, San Antonio, TX 78229 USA. Hebrew Univ Jerusalem, Hadassah Fac Dent Med, Dept Periodont, Jerusalem, Israel. Univ Gottingen, Dept Orthopaed, D-3400 Gottingen, Germany. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Inst Straumann, Waldenburg, Switzerland. RP Boyan, BD (reprint author), Univ Texas, Hlth Sci Ctr, Dept Orthopaed, Mail Code 7774,7703 Floyd Curl Dr, San Antonio, TX 78229 USA. EM boyanb@uthscsa.edu OI Dean, David/0000-0002-4512-9065 FU NIDCR NIH HHS [DE-05937, DE-08603] NR 38 TC 69 Z9 70 U1 0 U2 9 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 APR PY 2001 VL 22 IS 7 BP 731 EP 741 DI 10.1016/S0142-9612(00)00241-6 PG 11 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA 403UJ UT WOS:000167060600013 PM 11246968 ER PT J AU Loredo, R Sanders, TG AF Loredo, R Sanders, TG TI Imaging of osteochondral injuries SO CLINICS IN SPORTS MEDICINE LA English DT Article ID CARTILAGE DEFECTS; FEMORAL CONDYLE; MR; DISSECANS; KNEE; STABILITY; PSEUDODEFECT; PITFALL AB Detecting articular cartilage defects in the knee is important because the signs and symptoms associated with such defects can be confused clinically with meniscal tears, synovial problems, and extensor mechanism dysfunction.(19) Unfortunately, cartilage is not visualized on conventional radiodraphs. Therefore, purely chondral lesions require standard arthrography, computed arthrotomography, magnetic resonance (MR) arthrography, or arthroscopy for accurate diagnosis. Unless there is a large free fragment, standard arthrography and computed arthrotomography are often nondiagnostic. MR imaging has been used to evaluate articular cartilage, although adequate imaging of articular cartilage remains difficult owing to the nonuniform composition of its structural architecture. In the past, many MR imaging techniques have been applied to the assessment of articular cartilage. A standard spin-echo MR imaging technique alone is generally inadequate to evaluate articular cartilage. Standard spin-echo technique combined with fat suppression has the added advantage of improving contrast between cartilage and fluid; however, it too is inadequate. Most simple gradient echo sequences do not allow detection of superficial or minor lesions of articular cartilage. A more advanced gradient echo technique has been developed, which has been advocated as the optimal technique for evaluation of cartilage; it is a spoiled gradient echo sequence using fat suppression and three-dimensional (3D) acquisition (SPGR) (Fig. 1). With this sequence, spatial resolution is high owing to the ability to obtain thin contiguous slices; the images can be reformatted in multiple planes; and there are high contrast-to-noise ratios between cartilage and fluid and between cartilage and bone(17) (Fig.2). Using SPCR MR imaging, the trilaminar appearance of the articular cartilage can be seen. The technique can be used to evaluate cartilage degeneration, demonstrating loss of signal in a superficial bright layer and varying degrees of loss of signal in intermediate and deep layers within the cartilage. Other MR imaging techniques used for cartilage analysis are subtraction magnetization-transfer contrast in-caging, short echo time projec-evidence of cartilage abnormality on MR images relates to the identification of fluid at the interface between the fragment and the parent bone. The MR imaging technique influences dramatically whether such fluid is identified. MR arthrography employing the intra-articular injection of gadolinium compounds can be advantageous in the delineation of the chondral surface and in the detection of intraarticular bodies. Optimally, MR imaging would allow direct analysis of the cartilage surface, and specific imaging sequences that are most suited to this analysis are still evolving. C1 Univ Texas, Hlth Sci Ctr, Dept Radiol, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. RP Loredo, R (reprint author), Univ Texas, Hlth Sci Ctr, Dept Radiol, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. NR 24 TC 32 Z9 33 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0278-5919 J9 CLIN SPORT MED JI Clin. Sports Med. PD APR PY 2001 VL 20 IS 2 BP 249 EP + DI 10.1016/S0278-5919(05)70305-7 PG 31 WC Sport Sciences SC Sport Sciences GA 445FH UT WOS:000169447100003 PM 11398357 ER PT J AU Pados, DA Medley, MJ Batalama, SN AF Pados, DA Medley, MJ Batalama, SN TI Adaptive antenna array receivers for spread-spectrum signals in non-Gaussian noise SO DIGITAL SIGNAL PROCESSING LA English DT Article DE antenna arrays; auxiliary-vector filters; CDMA; impulsive noise; interference suppression; space-time adaptive processing; spread-spectrum communications ID INTERFERENCE ENVIRONMENT; LOCALLY OPTIMUM; PERFORMANCE; CHANNELS; DESIGN; FILTER AB We consider the problem of recovering a spread-spectrum (SS) signal in the presence of unknown highly correlated spread-spectrum interference and impulsive noise. In terms of basic system and signal model considerations, we assume availability of a narrowband adaptive antenna array that experiences additive white Gaussian noise in time and across elements, as well as impulsive disturbance with direction-of-arrival (DOA) that changes at the chip rate. The space-time receiver design developed in this work is characterized by the following attributes: (i) Adaptive interference suppression is pursued in the joint space-time domain. (ii) An adaptive parametric nonlinear front end offers effective suppression of impulsive disturbances at low computational cost. (iii) An adaptive auxiliary-vector linear filter postprocessor offers effective, low-complexity suppression of SS interferers and leads to superior bit-error-rate (BER) performance under rapid, short-data-record system adaptation. Numerical and simulation comparisons with plain and outlier resistant space-time minimum-variance-distortionless-response (MVDR) filtering procedures are included to illustrate and support the theoretical developments. (C) 2001 academic Press. C1 SUNY Buffalo, Dept Elect Engn, Buffalo, NY 14260 USA. USAF, Res Lab, IFGC, Rome, NY 13441 USA. RP SUNY Buffalo, Dept Elect Engn, Buffalo, NY 14260 USA. EM pados@eng.buffalo.edu; medleym@rl.af.mil; batalama@eng.buffalo.edu NR 34 TC 2 Z9 2 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1051-2004 EI 1095-4333 J9 DIGIT SIGNAL PROCESS JI Digit. Signal Prog. PD APR PY 2001 VL 11 IS 2 BP 144 EP 158 DI 10.1006/dspr.2001.0392 PG 15 WC Engineering, Electrical & Electronic SC Engineering GA 425QG UT WOS:000168302200006 ER PT J AU Alder, FA Dill, JC Lindsey, AR AF Alder, FA Dill, JC Lindsey, AR TI Performance of simplex signaling in circular trellis-coded modulation SO DIGITAL SIGNAL PROCESSING LA English DT Article AB This paper presents measures of performance of simplex signaling in a circular trellis-coded modulation (CTCM) scheme. Background is given on both CTCM and simplex signaling. The CTCM system is shown to give substantial coding gain when compared to conventional BPSK. Performance is also shown to improve as trellis size increases. (C) 2001 Academic Press. C1 Ohio Univ, Russ Coll Engn & Technol, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. USAF, Res Lab, Rome, NY 13441 USA. RP Alder, FA (reprint author), Ohio Univ, Russ Coll Engn & Technol, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1051-2004 J9 DIGIT SIGNAL PROCESS JI Digit. Signal Prog. PD APR PY 2001 VL 11 IS 2 BP 159 EP 167 DI 10.1006/dspr.2001.0393 PG 9 WC Engineering, Electrical & Electronic SC Engineering GA 425QG UT WOS:000168302200007 ER PT J AU Lawitz, EJ Kadakia, SC Jeffries, M Aggarwal, A Bilir, B Galen, EA Diamond, K James, D Jolley, J Matossian, H Nguyen, T Warfield, P AF Lawitz, EJ Kadakia, SC Jeffries, M Aggarwal, A Bilir, B Galen, EA Diamond, K James, D Jolley, J Matossian, H Nguyen, T Warfield, P TI Continuous combination therapy has superior viral clearance compared to standard combination therapy - A multicenter, randomized trial SO GASTROENTEROLOGY LA English DT Meeting Abstract C1 Brooke Army Med Ctr, San Antonio, TX USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0016-5085 J9 GASTROENTEROLOGY JI Gastroenterology PD APR PY 2001 VL 120 IS 5 SU 1 MA 1954 BP A381 EP A381 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 429KA UT WOS:000168514701889 ER PT J AU Connor, P Vaughan, J Schutz, S Jowell, P Leung, J Nickl, N Libby, E Barkun, ANG Cotton, PB AF Connor, P Vaughan, J Schutz, S Jowell, P Leung, J Nickl, N Libby, E Barkun, ANG Cotton, PB TI Towards benchmarking in endoscopy; A multi-center database analysis. SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Med Univ S Carolina, Charleston, SC 29425 USA. USAF, Med Ctr, Travis AFB, CA USA. Duke Univ, Med Ctr, Durham, NC USA. Univ Calif Davis, Sacramento, CA 95817 USA. Univ Kentucky, Lexington, KY USA. McGill Univ, Montreal, PQ, Canada. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY, INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 2001 VL 53 IS 5 SU S MA 4310 BP AB198 EP AB198 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 429XG UT WOS:000168542800498 ER PT J AU Patel, RS Mulcahy, HE Connor, P Schutz, S Grant, D Jowell, P Leung, J Nickl, N Libby, E Barkun, ANG Cotton, PB AF Patel, RS Mulcahy, HE Connor, P Schutz, S Grant, D Jowell, P Leung, J Nickl, N Libby, E Barkun, ANG Cotton, PB TI Clinical features and distal endoscopic findings associated with proximal colonic neoplasia in symptomatic patients: An anaylysis of 7,607 patients undergoing colonoscopy in clinical practice SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Med Univ S Carolina, Charleston, SC 29425 USA. USAF, David Grant Med Ctr, Travis AFB, CA USA. Duke Univ, Med Ctr, Durham, NC USA. USC Davis, Sacramento, CA USA. Univ Kentucky, Lexington, KY USA. Tufts Univ, New England Med Ctr, Boston, MA 02111 USA. McGill Univ, Montreal, PQ, Canada. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY, INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 2001 VL 53 IS 5 SU S MA 4277 BP AB190 EP AB190 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 429XG UT WOS:000168542800465 ER PT J AU Patel, RS Mulcahy, HE Conner, P Schutz, S Jowell, PS Leung, J Nickl, N Libby, E Barkun, ANG Cotton, PB AF Patel, RS Mulcahy, HE Conner, P Schutz, S Jowell, PS Leung, J Nickl, N Libby, E Barkun, ANG Cotton, PB TI The association between diverticulosis and lower gastrointestinal neoplasia: A study of 7,544 patients undergoing colonoscopy SO GASTROINTESTINAL ENDOSCOPY LA English DT Meeting Abstract C1 Med Univ S Carolina, Charleston, SC 29425 USA. USAF, Med Ctr, Travis AFB, CA USA. Duke Univ, Med Ctr, Durham, NC USA. Univ Calif Davis, Sacramento, CA 95817 USA. Univ Kentucky, Lexington, KY USA. Tufts Univ, New England Med Ctr, Boston, MA 02111 USA. McGill Univ, Montreal, PQ, Canada. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY, INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0016-5107 J9 GASTROINTEST ENDOSC JI Gastrointest. Endosc. PD APR PY 2001 VL 53 IS 5 SU S MA 4270 BP AB188 EP AB188 PG 1 WC Gastroenterology & Hepatology SC Gastroenterology & Hepatology GA 429XG UT WOS:000168542800458 ER PT J AU Kane, T Grime, B Franke, S Kudeki, E Urbina, J Kelley, M Collins, S AF Kane, T Grime, B Franke, S Kudeki, E Urbina, J Kelley, M Collins, S TI Joint observations of sodium enhancements and field-aligned ionospheric irregularities SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID E-REGION; RADAR OBSERVATIONS; PUERTO-RICO; SPORADIC-E; WAVE; TURBULENCE; LAYERS; LIDAR AB Resonance Lidar observations of neutral sodium Instrumentation and VHF coherent scatter radar observations of field-aligned 3-meter irregularities were obtained during the Coqui II rocket campaign in Puerto Rico. The Lidar, a facility instrument at the Arecibo Observatory (18.3 degrees N, 66.8 degrees W), and the University of Illinois Radar, located near Salinas on the south of the island, both monitored volumes near where the uplegs of the nominal rocket trajectories intersected the E-region. The Observatory's Incoherent Scatter Radar was also used to characterize the plasma layers. Preliminary investigation of the data sets has shown a potential correspondence between VHF backscatter from plasma layers and a new class of characteristic enhancements in the neutral sodium. C1 Penn State Univ, Dept Elect Engn, University Pk, PA 16802 USA. USAF, Res Lab, Starfire Opt Range, Kirtland AFB, NM 87117 USA. Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. Cornell Univ, Sch Elect & Comp Engn, Ithaca, NY 14853 USA. RP Kane, T (reprint author), Penn State Univ, Dept Elect Engn, 121 Elect Engn E, University Pk, PA 16802 USA. NR 16 TC 17 Z9 18 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 1 PY 2001 VL 28 IS 7 BP 1375 EP 1378 DI 10.1029/2000GL012176 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 415GZ UT WOS:000167714000052 ER PT J AU Mertens, CJ Mlynczak, MG Lopez-Puertas, M Wintersteiner, PP Picard, RH Winick, JR Gordley, LL Russell, JM AF Mertens, CJ Mlynczak, MG Lopez-Puertas, M Wintersteiner, PP Picard, RH Winick, JR Gordley, LL Russell, JM TI Retrieval of mesospheric and lower thermospheric kinetic temperature from measurements of CO2 15 mu m Earth limb emission under non-LTE conditions SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID NONLOCAL THERMODYNAMIC-EQUILIBRIUM; ATMOSPHERE; EXCITATION; RADIANCE; MODEL AB We present a new algorithm for the retrieval of kinetic temperature in the terrestrial mesosphere and lower thermosphere from measurements of CO2 15 mum earth limb emission. Non-local-thermodynamic-equilibrium (non-LTE) processes are rigorously included in the new algorithm, necessitated by the prospect of satellite-based limb radiance measurements to be made from the TIMED/SABER platform in the near future between 15 km and 120 km tangent altitude. The algorithm requires 20 seconds to retrieve temperature to better than 3 K accuracy on a desktop computer, easily enabling its use in operational processing of satellite data. We conclude this letter with a study of the sensitivity of the retrieved temperatures to parameters used in the non-LTE models, including sensitivity to the rate constant for physical quenching of CO2 bending mode vibrations by atomic oxygen. C1 NASA, Langley Res Ctr, Hampton, VA 23681 USA. ARCON Corp, Waltham, MA USA. CSIC, Inst Astrofis Andalucia, Granada, Spain. USAF, Res Labs, Space Vehicles Directorate, Hanscom AFB, MA USA. Hampton Univ, Hampton, VA 23668 USA. RP Mertens, CJ (reprint author), NASA, Langley Res Ctr, 21 Langley Blvd,Mail Stop 401B, Hampton, VA 23681 USA. RI Mlynczak, Martin/K-3396-2012; Lopez Puertas, Manuel/M-8219-2013 OI Lopez Puertas, Manuel/0000-0003-2941-7734 NR 16 TC 163 Z9 166 U1 1 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD APR 1 PY 2001 VL 28 IS 7 BP 1391 EP 1394 DI 10.1029/2000GL012189 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 415GZ UT WOS:000167714000056 ER PT J AU Kastle, T Toussaint, J Robertson, RS AF Kastle, T Toussaint, J Robertson, RS TI Continuous transverse stub technology SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB Military and civil radar and communication systems utilize phased array antennas that require hundreds or, in some cases, thousands of transmit/receive (T/R) modules. T/R modules, even when low cost, drive the total RF system cost to an undesirable level, resulting in fewer systems being purchased. This paper will review the application of continuous transverse stub (CTS) antenna technology to reduce the number of T/R modules required and, thus, the overall RF system cost, and military and civil applications and their respective cost savings. C1 AFRL, SNRR, Sensor Directorate, Wright Patterson AFB, OH 45433 USA. RP Kastle, T (reprint author), AFRL, SNRR, Sensor Directorate, Bldg 620,Area B,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD APR PY 2001 VL 16 IS 4 BP 29 EP 31 DI 10.1109/62.918025 PG 3 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 424LM UT WOS:000168233800006 ER PT J AU Haworth, MD Luginsland, JW Lemke, RW AF Haworth, MD Luginsland, JW Lemke, RW TI Improved cathode design for long-pulse MILO operation SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE bipolar flow; high-power microwaves; magnetically insulated transmission line oscillator; MILO; pulse shortening ID TRANSMISSION-LINE OSCILLATOR; B ION DIODES; EMISSION AB An improved cathode design fur a magnetically insulated transmission line oscillator (MILO) has resulted in extending the radiated microwave pulse duration from 200 ns to over 400 ns, This was accomplished by maximizing the emission uniformity in the launch-point region of the cathode which, in turn, minimized anode plasma formation. The extended RF pulse duration has allowed us to find evidence of a new pulse-shortening mechanism late in the beam pulse: anode plasma formation in the load region. C1 Directed Energy Directorate, AF Res Lab, Kirtland AFB, NM 87117 USA. Sandia Natl Labs, Z Pinch & Target Theory Dept, Albuquerque, NM 87185 USA. RP Haworth, MD (reprint author), Directed Energy Directorate, AF Res Lab, Kirtland AFB, NM 87117 USA. NR 16 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 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD APR PY 2001 VL 29 IS 2 BP 388 EP 392 DI 10.1109/27.922751 PN 2 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 431ZR UT WOS:000168662100012 ER PT J AU Kapila, V Sparks, AG Pan, HZ AF Kapila, V Sparks, AG Pan, HZ TI Control of systems with actuator saturation non-linearities: an LMI approach SO INTERNATIONAL JOURNAL OF CONTROL LA English DT Article ID LYAPUNOV FUNCTIONS; DESIGN AB In this paper, we develop a static, full-state feedback and a dynamic, output feedback control design framework for continuous-time, multivariable, linear, time-invariant systems subject to time-invariant, sector-bounded, input non-linearities. The proposed framework directly accounts for robust stability and robust performance over the class of input non-linearities. Specifically, the problem of feedback control design in the presence of time-invariant, sector-bounded, input non-linearities is embedded within a Lure-Postnikov Lyapunov function framework by constructing a set of linear-matrix-inequality conditions whose solution guarantees closed-loop asymptotic stability with guaranteed domains of attraction in the face of time-invariant, sector-bounded, actuator non-linearities. A detailed numerical algorithm is provided for solving the linear-matrix-inequality conditions arising in actuator saturation control. Three illustrative numerical examples are presented to demonstrate the effectiveness of the proposed approach. C1 Polytech Univ, Dept Mech Aerosp & Mfg Engn, Brooklyn, NY 11201 USA. USAF, Res Lab, AFRL VAAD, Wright Patterson AFB, OH 45433 USA. RP Kapila, V (reprint author), Polytech Univ, Dept Mech Aerosp & Mfg Engn, 6 Metrotech Ctr, Brooklyn, NY 11201 USA. EM vkapila@duke.poly.edu NR 18 TC 18 Z9 19 U1 2 U2 3 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0020-7179 J9 INT J CONTROL JI Int. J. Control PD APR PY 2001 VL 74 IS 6 BP 586 EP 599 DI 10.1080/00207170010023151 PG 14 WC Automation & Control Systems SC Automation & Control Systems GA 423MG UT WOS:000168179600006 ER PT J AU Young, RJ Gilson, RT Yanase, D Elston, DM AF Young, RJ Gilson, RT Yanase, D Elston, DM TI Cutaneous sarcoidosis SO INTERNATIONAL JOURNAL OF DERMATOLOGY LA English DT Review ID SCAR SARCOIDOSIS; THALIDOMIDE; GRANULOMAS; DISEASE; THERAPY C1 Brooke Army Med Ctr, Dept Dermatol, Ft Sam Houston, TX 78234 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. RP Elston, DM (reprint author), Brooke Army Med Ctr, Dept Dermatol, Ft Sam Houston, TX 78234 USA. NR 27 TC 25 Z9 26 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0011-9059 J9 INT J DERMATOL JI Int. J. Dermatol. PD APR PY 2001 VL 40 IS 4 BP 249 EP 253 DI 10.1046/j.1365-4362.2001.01151.x PG 5 WC Dermatology SC Dermatology GA 452ZQ UT WOS:000169890100002 PM 11454079 ER PT J AU Sendeckyj, GP AF Sendeckyj, GP TI Constant life diagrams - a historical review SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Review DE constant life diagrams; fatigue; history AB A historical review of the early development of constant life diagrams (variously referred to as Goodman. Smith, Haigh, etc. diagrams) is presented. It is shown that there were two distinct approaches to the formulation of constant life diagrams for fatigue design purposes. The first one was based on Wohler's fatigue experiments and involved engineering curve fits of the fatigue endurance data. The Launhardt-Weyrauch, Gerber and Johnson formulae art: the main representatives of this approach. The second approach is based on the dynamic theory used for bridge design. The Fidler-Goodman formula is an example of this approach. The early proponents of the second approach questioned Wohler's test results and did not believe that they could be used for design purposes. Finally, the first books on fatigue of metals introduced citation inaccuracies, which were propagated by subsequent authors. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Mat & Mfg Directorate, Res Lab, MLLM,Met Branch, Wright Patterson AFB, OH 45433 USA. RP Sendeckyj, GP (reprint author), USAF, Mat & Mfg Directorate, Res Lab, MLLM,Met Branch, Wright Patterson AFB, OH 45433 USA. NR 47 TC 33 Z9 34 U1 1 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD APR PY 2001 VL 23 IS 4 BP 347 EP 353 DI 10.1016/S0142-1123(00)00077-3 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 411QR UT WOS:000167511200007 ER PT J AU Butler, RJ Byerley, AR VanTreuren, K Baughn, JW AF Butler, RJ Byerley, AR VanTreuren, K Baughn, JW TI The effect of turbulence intensity and length scale on low-pressure turbine blade aerodynamics SO INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW LA English DT Article ID HEAT-TRANSFER MEASUREMENTS; STATOR ROTOR INTERACTIONS; REYNOLDS-NUMBER; DOWNSTREAM; AIRFOIL; CASCADE; REGION AB Unpredicted losses have been observed in low-pressure gas turbine stages during high altitude operation. These losses have been attributed to aerodynamic separation on the turbine blade suction surfaces. To gain insight into boundary layer transition and separation for these low Reynolds number conditions, the heat transfer distribution on a Langston turbine blade shape was measured in a linear cascade wind tunnel for turbulence levels of 0.8% and 10% and Reynolds numbers of 40-80k. Turbulence levels of 10% were generated using three passive biplanar lattice grids with square-bar widths of 1.27, 2.54 and 6.03 cm to investigate the effect of turbulence length scale. The heat transfer was measured using a uniform heat flux (UHF) liquid crystal technique. As turbulence levels increased, stagnation heat transfer increased and the location of the suction-side boundary layer transition moved upstream toward the blade leading edge, For this turbine blade shape the transition location did not depend on turbulence length scale, the location is more dependent on pressure distribution, Reynolds number and turbulence intensity. For the 10% turbulence cases, the smaller length scales had a larger affect on heat transfer at the stagnation point. A laser tuft method was used to differentiate between boundary layer transition and separation on the suction surface of the blade. Separation was observed for all of the low turbulence (clean tunnel) cases while transition was observed for all of the 10% turbulence cases. Separation and transition locations corresponded to local minimums in heat transfer. Reattachment points did not correspond to local maximums in heat transfer, but instead, the heat transfer coefficient continued to rise downstream of the reattachment point. For the clean tunnel cases, streamwise streaks of varying heat transfer were recorded on the concave pressure side of the turbine blade. These streaks are characteristic of either Gortler vortices or a three-dimensional transition process. For the 10% turbulence cases, these streaks were not present. The results presented in this paper show that turbulence length scale, in addition to intensity have an important contribution to turbine blade aerodynamics and are important to CFD modelers who seek to predict boundary layer behavior in support of turbine blade design optimization efforts. (C) 2001 Elsevier Science Inc. All rights reserved. C1 USAF, Aeronaut Syst Ctr, Propuls Dev Syst Off, Wright Patterson AFB, OH 45433 USA. USAF Acad, Dept Aeronaut, Colorado Springs, CO 80840 USA. Baylor Univ, Dept Engn, Waco, TX 76798 USA. Univ Calif Davis, Davis, CA 95616 USA. RP Butler, RJ (reprint author), USAF, Aeronaut Syst Ctr, Propuls Dev Syst Off, Bldg 28,Room 201,2145 Mohahan Way, Wright Patterson AFB, OH 45433 USA. NR 34 TC 24 Z9 24 U1 0 U2 10 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0142-727X J9 INT J HEAT FLUID FL JI Int. J. Heat Fluid Flow PD APR PY 2001 VL 22 IS 2 BP 123 EP 133 DI 10.1016/S0142-727X(00)00081-3 PG 11 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA 413TA UT WOS:000167627000002 ER PT J AU Miracle, D AF Miracle, D TI Metallic composites in space: A status report SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Editorial Material C1 USAF, Res Lab, Wright Patterson Air Force Base, Metall Composites Res Grp, Dayton, OH 45433 USA. RP Miracle, D (reprint author), USAF, Res Lab, Wright Patterson Air Force Base, Metall Composites Res Grp, Dayton, OH 45433 USA. NR 1 TC 2 Z9 2 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD APR PY 2001 VL 53 IS 4 BP 12 EP 12 DI 10.1007/s11837-001-0138-0 PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 419XP UT WOS:000167974500001 ER PT J AU Vreugdenhil, AJ Balbyshev, VN Donley, MS AF Vreugdenhil, AJ Balbyshev, VN Donley, MS TI Nanostructured silicon sol-gel surface treatments for Al 2024-T3 protection SO JOURNAL OF COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 78th Annual Meeting of the Federation-of-Societies-for-Coatings-Technology CY OCT 18, 2000 CL CHICAGO, ILLINOIS SP Federat Soc Coatings Technol ID COATINGS AB Current coatings for aircraft corrosion protection are based on chromate surface treatments, primers, and topcoats. One approach to developing a chromate-free surface treatment is through the use of sol-gel materials that interact strongly with both the substrate and the subsequent polymer layers. Results are reported here on a new sol-gel technique using a pre-forming, self-assembled, non-phase particle (SNAP) sol-gel system. SNAP films have been investigated by infrared spectroscopy atomic force microscopy, and electrochemical methods. Potentiodynamic polarization and electrochemical impedance spectroscopy demonstrated that the SNAP system generates high quality defect-free, durable films. Formulation parameters, including crosslink density and coupling agent application, were optimized based on experimental results. C1 USAF, Res Labs, Washington, DC 20330 USA. RP Vreugdenhil, AJ (reprint author), Univ Dayton, Res Inst, 300 Coll Pk, Dayton, OH 45469 USA. NR 26 TC 68 Z9 76 U1 2 U2 8 PU FEDERATION SOC COATING TECH PI BLUE BELL PA 492 NORRISTOWN ROAD, BLUE BELL, PA 19422 USA SN 0361-8773 J9 J COATING TECHNOL JI J. Coat. Technol. PD APR PY 2001 VL 73 IS 915 BP 35 EP 43 DI 10.1007/BF02730029 PG 9 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 422XT UT WOS:000168145100012 ER PT J AU John, R Buchanan, DJ AF John, R Buchanan, DJ TI Bridging stress distributions during fatigue crack growth in continuously reinforced [0] metal matrix composites SO JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH LA English DT Article DE bridging stress; bridging stress intensity factor; crack growth; fatigue; fiber bridging; metal matrix composite; shear lag; titanium matrix composite ID OPENING DISPLACEMENT; FIBER COMPOSITES; SCS-6/TIMETAL(R)21S; INTERFACE; MECHANICS; FRACTURE AB An optimization procedure was developed to deduce the fiber bridging stresses from crack opening displacements measured in situ during crack growth. This procedure was used to determine the bridging stress distribution during fatigue crack growth in a unidirectionally reinforced metal matrix composite (SCS-6/TIMETAL(R)21S). The bridging stress is non-zero at the crack tip contrary to predictions from conventionally used shear lag models. The bridging stress at the crack tip is proportional to the applied far-field stress. The deduced bridging law is similar to the new shear lag models with non-zero bridging stresses at the crack tip. Any bridging model can be used to predict the crack growth behavior by choosing appropriate values of the frictional shear stress (tau). Consequently, the magnitude of the stresses in the fibers bridging the crack will depend on the fiber bridging model. Hence, the fiber tensile strength required to predict the onset of fiber failure will also depend on the fiber bridging model. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP John, R (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, Wright Patterson AFB, OH 45433 USA. NR 36 TC 0 Z9 0 U1 0 U2 4 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 APR PY 2001 VL 23 IS 2 BP 69 EP 81 PG 13 WC Materials Science, Composites; Polymer Science SC Materials Science; Polymer Science GA 490KW UT WOS:000172051900002 ER PT J AU Fang, R Gu, H O'Keefe, MJ O'Keefe, TJ Shih, WS Leedy, KD Cortez, R AF Fang, R Gu, H O'Keefe, MJ O'Keefe, TJ Shih, WS Leedy, KD Cortez, R TI Spontaneous, non-aqueous electrochemical deposition of copper and palladium on Al and Al(Cu) thin films SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT Symposium on Advances in Interconnect and Packaging Materials at the TMS Fall Meeting CY OCT 08-12, 2000 CL ST LOUIS, MISSOURI SP TMS DE copper; palladium; non-aqueous; selective; electrochemical deposition; solder AB Copper and palladium seed layers have been successfully deposited from organic solutions onto patterned and unpatterned pure aluminum and Al(0.5%Cu) thin films using an immersion displacement process. The reaction occurs at ambient temperature and pressure by a spontaneous electrochemical mechanism. Copper and palladium deposition using the organic solution was studied as a function of reaction time and Cu or Pd concentration in the solution. It was found that both time and the initial ionic metal concentration significantly influence deposit morphology, particle size and shape, and adherence. Nucleation of Cu or Pd sub-micron particles on both Al and Al(Cu) surfaces occurred in less than one minute while nucleation density and particle size increased with longer deposition times. Increasing the copper or palladium concentration in the organic solution resulted in an increase in the final particle size of the seed crystals. However, an increase in deposition time and metal concentration in the organic solution caused more extensive dissolution and pitting of the aluminum thin films. The Cu and Pd deposits were effectively used as catalytic sites for subsequent electroless or electrolytic copper deposition using conventional aqueous processes. C1 Univ Missouri, Dept Met Engn, Rolla, MO 65409 USA. Univ Missouri, Mat Res Ctr, Rolla, MO 65409 USA. Brewer Sci Inc, Rolla, MO 65401 USA. USAF, Res Lab, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Fang, R (reprint author), Univ Missouri, Dept Met Engn, Rolla, MO 65409 USA. NR 6 TC 4 Z9 4 U1 1 U2 8 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 2001 VL 30 IS 4 BP 349 EP 354 DI 10.1007/s11664-001-0042-y PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 422XK UT WOS:000168144400012 ER PT J AU Pallamraju, D Baumgardner, J Chakrabarti, S Pedersen, TR AF Pallamraju, D Baumgardner, J Chakrabarti, S Pedersen, TR TI Simultaneous ground based observations of an auroral arc in daytime/twilighttime OI 630.0 nm emission and by incoherent scatter radar SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID DAYGLOW PHOTOMETRY; CLEFT AURORA; POLAR-CAP; LAYER; ANTARCTICA; SPECTRUM; AIRGLOW; PATCHES AB We present the ground-based oxygen 630.0 nm daytime optical measurements of a discrete auroral are from Sondre Stromfjord, Greenland. The optical measurements were made using an imaging echelle spectrograph built at Boston University. We show that the auroral optical signature extracted from the blue-sky background agrees closely in both space and time with the aurorally enhanced electron densities at 200 km altitude obtained simultaneously by the incoherent scatter radar. The dayglow measurements are also in good agreement with the integrated emission rates modeled using the measured N-e, T-e, and T-i profiles from the radar. The results reported in this paper demonstrate the potential of this spectrograph to observe aurora during daytime, and it promises to be a valuable complement to the existing tools for the investigation of upper atmospheric phenomena. C1 Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Pallamraju, D (reprint author), Boston Univ, Ctr Space Phys, 725 Commonwealth Ave, Boston, MA 02215 USA. NR 28 TC 17 Z9 17 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 2001 VL 106 IS A4 BP 5543 EP 5549 DI 10.1029/2000JA000244 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 418MC UT WOS:000167895100002 ER PT J AU Starks, MJ Lee, MC Jastrzebski, P AF Starks, MJ Lee, MC Jastrzebski, P TI Interhemispheric propagation of VLF transmissions in the presence of ionospheric HF heating SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID WHISTLER-MODE SIGNALS; ELECTRON-DENSITY; GROUP DELAYS; GENERATION; DUCTS AB Recent experiments carried out at the Arecibo Observatory in Puerto Rico and the magnetically conjugate location in Argentina suggest a connection between the Prevalence and intensity of the interhemispheric propagation of VLF transmissions and HF heating of the ionosphere. During several nights of the study the O-mode CW heater appeared to enhance the coupling of VLF transmissions into the affected region of plasma. These signals presumably then entered plasmaspheric ducts more efficiently and led to conjugate measurements of relatively high amplitude. No such effects were seen with pulsed or X-mode heating. Short time resolution measurements of fading transmissions were marked by transit delays and amplitudes that remained nearly constant as the interhemispheric VLF signals diminished, consistent with the model of a plasmaspheric duct complemented by favorable plasma structures extending well into the F region but producing the majority of the total transit delay at plasmaspheric altitudes. It is also suggested that weak long-delay receptions often observed in these data are most probably prolongitudinal whistlers that are not ducted but which represent a potential contaminant in ducted VLF experiments of all types. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RP Starks, MJ (reprint author), USAF, Res Lab, Space vehicles Directorate, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 35 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 2001 VL 106 IS A4 BP 5579 EP 5591 DI 10.1029/2000JA000090 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 418MC UT WOS:000167895100005 ER PT J AU Ober, DM Maynard, NC Burke, WJ Peterson, WK Sigwarth, JB Frank, LA Scudder, JD Hughes, WJ Russell, CT AF Ober, DM Maynard, NC Burke, WJ Peterson, WK Sigwarth, JB Frank, LA Scudder, JD Hughes, WJ Russell, CT TI Electrodynamics of the poleward auroral border observed by Polar during a substorm on April 22, 1998 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SUBAURORAL ION DRIFTS; SHEET BOUNDARY-LAYER; ELECTRIC-FIELDS; PLASMA SHEET; MAGNETOTAIL RECONNECTION; IONOSPHERIC SIGNATURES; CURRENT SYSTEMS; MAGNETIC-FIELD; SPACECRAFT; INSTRUMENT AB Observations from Polar during a substorm on April 22, 1998, are used to specify electrodynamic characteristics of the high-latitude auroral boundary on the nightside. Polar was moving equatorward near invariant latitude 72 degrees, 2305 magnetic local time as it crossed the auroral boundary near the end of the substorm's expansion phase. This boundary was marked by severe east-west plasma flow shears, a reversal of the in-track electric field component, and multiple field-aligned currents. Harmonizing ground measurements with auroral images and in situ particle and field data from Polar reveals five electrodynamic features of the boundary. (1) A 20-min delay occurred between substorm onset and when the total magnetic flux in the polar cap began to decrease. This represents the time that elapsed before reconnection of open lobe flux began along a near-Earth X-line. (2) The reconnection electric field at the ionospheric projection of the X-line ranged between 20 and 70 mV m(-1) Reconnection was intermittent, turning on and off at different locations. (3) Electric and magnetic field structures observed by Polar suggest that Alfven waves propagating along the auroral boundary carried a double-layer current. Downward Poynting flux was observed at the poleward auroral boundary associated with these currents. (4) Magnetic and electric field oscillations with periods of similar to 90 s were detected on open field lines beginning similar to4 min before Polar entered the auroral oval. Oscillations with similar frequencies were observed both on the ground near Polar's magnetic footprint and at geosynchronous orbit. This indicates that the oscillations represent a large-scale phenomenon occurring over a large portion of the nightside magnetosphere. Coupling on open field lines derives from fringing fields associated with ionospheric closure of DP 1 currents. (5) Upward flowing hydrogen and oxygen ions were detected at and equatorward of the auroral boundary. Perpendicularly accelerated O+ ions detected in the immediate vicinity of the boundary can be explained by direct acceleration by the ambient electric field perpendicular to the local magnetic field. Equatorward of the boundary, O+ distributions were typical of ion conics. C1 Mission Res Corp, Nashua, NH 03062 USA. USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. Lockheed Martin, Space Phys Lab, Palo Alto, CA 94304 USA. Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA. RP Ober, DM (reprint author), Mission Res Corp, 1 Tara Blvd,Suite 302, Nashua, NH 03062 USA. RI Scudder, Jack/D-8417-2013; Peterson, WK/A-8706-2009; OI Scudder, Jack/0000-0001-7975-5630; Peterson, WK/0000-0002-1513-6096; Russell, Christopher/0000-0003-1639-8298 NR 47 TC 16 Z9 16 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 2001 VL 106 IS A4 BP 5927 EP 5943 DI 10.1029/2000JA003024 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 418MC UT WOS:000167895100032 ER PT J AU Pinto, LA Blazevic, V Anderson, SA Venzon, DJ Mac Trubey, C Rowe, T Katz, JM Liewehr, D Dolan, MJ Shearer, GM AF Pinto, LA Blazevic, V Anderson, SA Venzon, DJ Mac Trubey, C Rowe, T Katz, JM Liewehr, D Dolan, MJ Shearer, GM TI Influenza virus-stimulated generation of anti-human immunodeficiency virus (HIV) activity after influenza vaccination in HIV-infected individuals and healthy control subjects SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID BLOOD MONONUCLEAR-CELLS; CD8(+) T-CELLS; PERIPHERAL-BLOOD; REVERSE TRANSCRIPTION; IFN-GAMMA; SEROPOSITIVE PATIENTS; SUPPRESSIVE FACTORS; CYTOKINE PRODUCTION; INTERFERON-GAMMA; DENDRITIC CELLS AB Influenza virus stimulation of leukocytes induces factors that suppress human immunodeficiency virus (HIV). The effect of influenza vaccination on influenza-induced anti-HIV activity was investigated. Influenza vaccine was administered to 25 control subjects and 20 HIV-infected patients. Antiviral activity, cytokine production, and influenza antibodies were assessed before and 2 and 6 weeks after vaccination. Immunization induced a statistically significant increase in antiviral activity in control subjects but not in HIV patients, although the number of patients who generated this activity increased. Pre- and postvaccination levels of anti-HIV activity were significantly lower in HIV patients. Vaccination of control subjects and HIV patients induced increases in production of interleukin-2 and interferon (IFN)-gamma, but not of IFN-alpha. Virus load and CD4 cell counts were not significantly altered. This study demonstrates impairment of antiviral activity in HIV patients, in addition to deficiencies in antibody responses and cytokine production. In summary, influenza vaccination can induce an increase in multiple immunologic components that remained impaired in HIV patients. C1 NCI, Expt Immunol Branch, NIH, Bethesda, MD 20892 USA. NCI, Biostat & Data Management Sect, Bethesda, MD 20892 USA. NCI, Intramural Res Support Program, Sci Applicat Int Corp Frederick, Frederick Canc Res & Dev Ctr, Frederick, MD 21701 USA. Henry M Jackson Fdn, San Antonio, TX USA. Wilford Hall USAF Med Ctr, Infect Dis Serv, Lackland AFB, San Antonio, TX 78236 USA. Ctr Dis Control & Prevent, Influenza Branch, Atlanta, GA USA. RP Shearer, GM (reprint author), NCI, Expt Immunol Branch, NIH, Bldg 10,Rm 4B36, Bethesda, MD 20892 USA. RI Venzon, David/B-3078-2008 FU NCI NIH HHS [N01-CA-56000] NR 39 TC 14 Z9 14 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD APR 1 PY 2001 VL 183 IS 7 BP 1000 EP 1008 DI 10.1086/319277 PG 9 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 409CL UT WOS:000167366900002 PM 11237823 ER PT J AU Tamirisakandala, S Medeiros, SC Frazier, WG Prasad, YVRK AF Tamirisakandala, S Medeiros, SC Frazier, WG Prasad, YVRK TI Strain-induced porosity during cogging of extra-low interstitial grade Ti-6AI-4V SO JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE LA English DT Article DE cogging; FEM analysis; hot working; strain-induced porosity; Ti-6Al-4V ID HOT DEFORMATION; TI-6AL-4V; MECHANISMS; CAVITATION AB The phenomenon of strain-induced porosity (SIP) in extra-low interstitial (ELI) grade Ti-6Al-4V with a transformed beta starting microstructure is investigated to understand its origin during alpha-beta cogging. For this purpose, the constitutive behavior of the material is coupled with finite-element method (FEM) simulations of the cogging process. Two distinct types of SIP relevant to cogging speeds and temperatures, viz., shear cracking and void nucleation, are identified, While the former occurs at the prior beta grain boundaries below 825 degreesC, the latter occurs at the prior colony boundaries when the deformation temperature is close to the beta transus. The FEM simulations have shown that deformation conditions existing in the midregion of the billet are favorable for void nucleation. The mechanism of void growth in the presence of tensile residual stress and temperature during resoaking is modeled using the Cocks-Ashby coupled growth model. Repeated cogging and resoaking steps cause multiplication of void population in large numbers. To avoid both types of defects in any region of the billet, a practical solution has been developed by introducing a differential temperature profile from the surface to the center, and the validity of the proposed scheme is verified with FEM heat-transfer simulations. C1 USAF, Res Lab, Mat & Mfg Directorate, MLMR,Mat Proc Design Branch, Wright Patterson AFB, OH 45433 USA. RP Tamirisakandala, S (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLMR,Mat Proc Design Branch, Wright Patterson AFB, OH 45433 USA. NR 15 TC 1 Z9 1 U1 0 U2 2 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9495 J9 J MATER ENG PERFORM JI J. Mater. Eng. Perform. PD APR PY 2001 VL 10 IS 2 BP 125 EP 130 DI 10.1361/105994901770345114 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 425MX UT WOS:000168295700002 ER PT J AU O'Reilly, JM Papadopoulos, K AF O'Reilly, JM Papadopoulos, K TI Novel organic-inorganic glasses SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB The preparation and properties of novel organic-inorganic glasses with phenyl groups covalently bonded to phosphorus in an inorganic glass are presented. Phenyl phosphonic acid (PPA) can be incorporated into tin and zinc fluorophosphate glasses (MO/MF2/PO(2.5)PPA) at levels up to 72 mol%. The T-g's of these glasses range from below room temperature to near 200 degreesC depending on glass composition. For low melt glasses, these glasses have low moisture absorption and may solubilize dyes, organic photoconductors, NLO molecules, and pharmaceuticals. Several applications have been considered. (C) 2001 Kluwer Academic Publishers. C1 Eastman Kodak Co, Res & Dev, Imaging Mat & Media, Rochester, NY 14650 USA. RP O'Reilly, JM (reprint author), USAF, Mat Lab, Polymer Branch, 2941 P St Rm 136, Wright Patterson AFB, OH 45433 USA. NR 20 TC 6 Z9 6 U1 0 U2 2 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. PD APR PY 2001 VL 36 IS 7 BP 1595 EP 1600 DI 10.1023/A:1017571130002 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 418VF UT WOS:000167914300003 ER PT J AU Karney, MY Cassidy, MS Zahn, CM Snyder, RR AF Karney, MY Cassidy, MS Zahn, CM Snyder, RR TI Melanosis of the vagina - A case report SO JOURNAL OF REPRODUCTIVE MEDICINE LA English DT Article DE melanosis; vaginal diseases; vaginal neoplasms ID MALIGNANT-MELANOMA AB BACKGROUND: Melanosis is a term given to lesions in which melanin pigment is confined to tire basal layer of squamous epithelium and on visual inspection may have an appearance similar to that of malignant melanoma. Although relatively common in the oral and gastrointestinal tract, melanosis is an uncommon finding in the female genital tract and especially rare in the vagina; most reported cases have been vulvar. CASE: A 43-year-old, nulliparous woman was rioted to have a pigmented lesion at the vaginal cuff during a routine annual examination one year after a hysterectomy. On physical examination, the lesion appeared as a coalescence of several small, pigmented areas at the cuff. Or? palpation the lesion was flat, having tire contour of normal vaginal mucosa, and was not indurated or tender. A biopsy revealed vaginal melanosis. Tire patient was followed conservatively, with annual examinations, which documented no change in color, size or contour of the lesion. At this writing tire patient is six years from presentation and doing well. CONCLUSION: Vaginal melanosis may be difficult to distinguish clinically from malignant,melanoma but carries a much different prognosis. A biopsy of any pigmented lesion is always indicated prior to determining the need for therapy versus observation. (J Reprod Med 2001;46:389-391). C1 Uniformed Serv Univ Hlth Sci, Dept Obstet & Gynecol, Bethesda, MD 20814 USA. David Grant US Air Force Med Ctr, Dept Obstet & Gynecol, Travis AFB, CA USA. USAF, Acad Hosp, Dept Obstet & Gynecol, Colorado Springs, CO USA. Univ Texas, Med Branch, Dept Obstet & Gynecol, Galveston, TX 77550 USA. Univ Texas, Med Branch, Gynecol Serv, Galveston, TX 77550 USA. RP Zahn, CM (reprint author), Uniformed Serv Univ Hlth Sci, Dept Obstet & Gynecol, 4301 Jones Bridge Rd, Bethesda, MD 20814 USA. NR 13 TC 6 Z9 6 U1 0 U2 0 PU SCI PRINTERS & PUBL INC PI ST LOUIS PA PO DRAWER 12425 8342 OLIVE BLVD, ST LOUIS, MO 63132 USA SN 0024-7758 J9 J REPROD MED JI J. Reprod. Med. PD APR PY 2001 VL 46 IS 4 BP 389 EP 391 PG 3 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 430KC UT WOS:000168572200010 PM 11354842 ER PT J AU Born, GH Goldstein, DB Thompson, B AF Born, GH Goldstein, DB Thompson, B TI An analytical theory for orbit determination SO JOURNAL OF THE ASTRONAUTICAL SCIENCES LA English DT Article; Proceedings Paper CT Astrodynamics Symposium CY MAR 21, 2000 CL COLLEGE STN, TEXAS AB The QuikScat spacecraft was launched in June 1999 and is currently measuring vector winds over the global oceans with a spatial resolution of 25 km and a temporal resolution of one day. The University of Colorado is responsible for mission operations, including production of the ephemeris used to produce the science data records. The navigation solutions from the onboard Motorola Vice Roy receiver are smoothed in a post-processing mode to produce the operational ephemeris. The objective of this study is to develop a simple yet effective method of smoothing the navigation solutions from the onboard GPS receiver in a post-processing mode to provide a medium accuracy continuous ephemeris. The navigation solutions prior to Selective Availability being turned off in May, 2000 had noise at the 100 ra level. Currently the noise level is around 10 in. However, this noise is high frequency relative to the dominant orbit perturbations periods. Hence, orbit determination accuracy with SA off is not significantly different from that presented here. The approach used is to augment a J(2) analytical theory for near-circular orbits to include additional frequencies due primarily to tesseral harmonics. Accuracy of the theory was tested through fits to simulated and actual QuikScat GPS receiver data. C1 Univ Colorado, Colorado Ctr Astrodynam Res, Boulder, CO 80309 USA. USAF, GPS Joint Program Off, Los Angeles, CA USA. RP Born, GH (reprint author), Univ Colorado, Colorado Ctr Astrodynam Res, Boulder, CO 80309 USA. NR 4 TC 7 Z9 7 U1 0 U2 1 PU AMER ASTRONAUTICAL SOC PI SPRINGFIELD PA 6352 ROLLING MILL PLACE SUITE 102, SPRINGFIELD, VA 22152 USA SN 0021-9142 J9 J ASTRONAUT SCI JI J. Astronaut. Sci. PD APR-JUN PY 2001 VL 49 IS 2 BP 345 EP 361 PG 17 WC Engineering, Aerospace SC Engineering GA 510AE UT WOS:000173185900008 ER PT J AU Josyula, E Bailey, WE AF Josyula, E Bailey, WE TI Vibration-dissociation coupling using master equations in nonequilibrium hypersonic blunt-body flow SO JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER LA English DT Article; Proceedings Paper CT AIAA 31st Plasmadynamics and Lasers Conference CY JUN 19-22, 2000 CL DENVER, COLORADO ID REENTRY CONDITIONS; NITROGEN; COLLISIONS; MODEL; VV AB Numerical simulations are presented of a steady-state hypersonic flow past a hemisphere cylinder. Two types of models, one a lumped Landau-Teller vibrational relaxation model (Landau, L., and Teller, E., "Zur Theorie der Schalldispersion," Physikalalische Zeitschrift der Sowjetunion, Vol. 10, No. 1, 1936, pp. 34-43) and the other a discrete state kinetic relaxation model (DSKR), were used to study effects of vibration-dissociation coupling on the flow physics. The widely used Park's dissociation model was used as baseline for coupling vibration and dissociation processes (Park, C., Nonequilibrium Hypersonic Aerothermodynamics, Wiley, New York, 1990, p. 114). For a Mach 8.6 flow both relaxation models matched experimental data. At Mach 11.18, however, the underprediction of shock-standoff distance by both relaxation models using Park's model for dissociation coupling provided the motivation to implement a new master equation-based (DSKR) depletion model. The new model was used to study the effect of dissociation on population depletion in the vibrational states of the nitrogen molecule. The new model helps explain the restricted success of Park's dissociation model in certain temperature ranges of hypersonic how past a blunt body. In the range of 5000-15,000 K, the new model yielded a substantial rate reduction relative to Park's equilibrium rate at lower temperatures and a consistent value at the high end. Application of the new model to a Mach 19.83 flow at reentry conditions resulted in an increase in the shock-standoff distance. C1 USAF, Res Lab, Air Vehicles Directorate, AFRL VAAC, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Dept Engn Phys, AFIT ENP, Wright Patterson AFB, OH 45433 USA. RP Josyula, E (reprint author), USAF, Res Lab, Air Vehicles Directorate, AFRL VAAC, 2210 8th St, Wright Patterson AFB, OH 45433 USA. NR 33 TC 29 Z9 29 U1 2 U2 6 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 APR-JUN PY 2001 VL 15 IS 2 BP 157 EP 167 DI 10.2514/2.6604 PG 11 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 424ZX UT WOS:000168264800004 ER PT J AU Bons, JP Sondergaard, R Rivir, RB AF Bons, JP Sondergaard, R Rivir, RB TI Turbine separation control using pulsed vortex generator jets SO JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 45th International Gas Turbine and Aeroengine Congress and Exhibition CY MAY 08-11, 2000 CL MUNICH, GERMANY DE separation; control; VGJ; turbine ID FLOW AB The application of pulsed vortex generator jets to control separation on the suction surface of a low-pressure turbine blade is reported. Blade Reynolds numbers in the experimental, linear turbine cascade match those Sor high-altitude aircraft engines and aft stages of industrial turbine engines with elevated turbine inlet temperatures. The vortex generator jets have a 30 deg pitch and a 90 deg skew to the free-stream direction. Jet flow oscillations up to 100 Hz are produced using a high-frequency solenoid feed valve. Results are compared to steady blowing at jet blowing ratios less than 4 and at two chordwise positions upstream of the nominal separation zone. Results show that pulsed vortex generator jets produce a bulk flow effect comparable to that of steady jets with an order of magnitude less massflow. Boundary layer traverses and blade static pressure distributions show that separation is almost completely eliminated with the application of unsteady blowing. Reductions of aver 50 percent in the wake loss profile of the controlled blade were measured. Experimental evidence suggests thai the mechanism for unsteady control lies in the starting and ending transitions of the pulsing cycle rather than the injected jet stream itself: Boundary layer spectra support this conclusion and highlight significant differences between the steady and unsteady control techniques. The pulsed vortex generator jets are effective nt both chordwise injection locations tested (45 and 63 percent axial chord) covering a substantial portion of the blade suction surface. This insensitivity to injection location bodes,well for practical application of pulsed VGJ control where the separation location may not be accurately known a priori. C1 USAF, Inst Technol, Wright Patterson AFB, OH 44135 USA. RP Bons, JP (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 44135 USA. RI Bons, Jeffrey/N-9854-2014 NR 18 TC 92 Z9 95 U1 1 U2 11 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0889-504X J9 J TURBOMACH JI J. Turbomach.-Trans. ASME PD APR PY 2001 VL 123 IS 2 BP 198 EP 206 DI 10.1115/1.1350410 PG 9 WC Engineering, Mechanical SC Engineering GA 439XG UT WOS:000169142400003 ER PT J AU Beutner, TJ Elliott, GS Williams, GW Baust, HD Crafton, J Carter, CD AF Beutner, TJ Elliott, GS Williams, GW Baust, HD Crafton, J Carter, CD TI Forebody and leading edge vortex measurement using planar Doppler velocimetry SO MEASUREMENT SCIENCE AND TECHNOLOGY LA English DT Article DE planar Doppler velocimetry; Doppler global velocimetry; vortex; laser; wind tunnel ID SPECTRAL-RESOLUTION LIDAR; HIGH-SPEED FLOWS AB The planar Doppler velocimetry (PDV) technique has been demonstrated by employing it in a large-scale wind tunnel to record velocity fields surrounding a model of a generic fighter plane. The PDV instrument employed here included the following: (i) a frequency monitoring system for measuring the laser frequency corresponding to each set of scattering images, (ii) two detector systems (each composed of two 16-bit CCD cameras), one viewing the model from the top of the wind tunnel and the second from the side; (iii) iodine vapour cells based on the starved-cell design, which eliminated the need for separate temperature control of the iodine reservoir; iv) a vibration-isolated, injection-seeded, Q-switched Nd:YAG laser and (v) custom data acquisition software for linking the four cameras, the laser and the frequency monitor The PDV instrument was validated by comparing the PDV-derived velocity to the known value in the empty wind tunnel. An error of about 1 m s(-1) out of an 18.9 m s(-1) velocity component was found; the image noise component (resulting primarily from the speckle effect) was found to be about 1 m s(-1). In addition, as a result of laser-sheet impingement on the model surface, velocities near the model surfaces are biased by background scattering effects. Nonetheless, it has been shown that PDV can be used effectively to map velocity fields with high spatial resolution over complex model geometries. Frame-averaged velocity images recorded at four axial stations along the model have shown the formation of forebody and leading-edge vortices and their complex interaction in the presence of the wing flow field. C1 USAF, Off Sci Res, NA, Arlington, VA 22203 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. Innovat Sci Solut Inc, Dayton, OH 45440 USA. RP USAF, Off Sci Res, NA, 801 N Randolph St, Arlington, VA 22203 USA. EM tom.beutner@afosr.af.mil NR 41 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0957-0233 EI 1361-6501 J9 MEAS SCI TECHNOL JI Meas. Sci. Technol. PD APR PY 2001 VL 12 IS 4 BP 378 EP 394 DI 10.1088/0957-0233/12/4/303 PG 17 WC Engineering, Multidisciplinary; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 425KV UT WOS:000168290500005 ER PT J AU Lagarde, D Chappuis, B Billaud, PF Ramont, L Chauffard, F French, J AF Lagarde, D Chappuis, B Billaud, PF Ramont, L Chauffard, F French, J TI Evaluation of pharmacological aids on physical performance after a transmeridian flight SO MEDICINE AND SCIENCE IN SPORTS AND EXERCISE LA English DT Article DE caffeine; melatonin; jet-lag; static exercises; dynamic exercises ID CIRCADIAN-RHYTHM DISORDERS; JET-LAG; TIME ZONES; EXERCISE PERFORMANCE; CAFFEINE INGESTION; PHASE-SHIFTS; MELATONIN; TEMPERATURE; TRAVEL; CATECHOLAMINE AB Purpose: The purpose of this study was to evaluate physical performance (static and dynamic) of U.S. Air Force reservists after an eastbound air travel across seven time zones and to estimate the pharmacological aids slow-release caffeine and melatonin versus placebo in attempt to overcome the decline in performance. Methods: 27 American volunteers were randomly divided into three groups: caffeine 300 mg, melatonin 5 mg, and placebo (lactose, capsules). Two days before the flight and 10 d after, three tests were performed: hand grip strength test (static performance), squat jump test (maximal height), and multiple jump test (power and endurance). All measures were repeated twice a day: morning and afternoon. Results: Zn placebo conditions, the static performance of the dominant hand decreased significantly during the first three mornings and tended to decrease the fourth morning. Simultaneously, the caffeine group's static performance increased significantly, whereas the melatonin group maintained its levers. No significant differences were observed the afternoons. No statistical differences appeared for the nondominant hand in the mornings or afternoons. Dynamic capacities presented no significant degradation after the travel. In the placebo group, for the squat jump test, performance increased from the fourth day. No real explanation can be given about this result. Conclusions: We demonstrated that slow-release caffeine and melatonin might be used to compensate for jet-lag troubles and particularly for the static physical performance decrease. The slow-release caffeine seems to be the best treatment, but its effects are only demonstrated on previously damaged performance. These preliminary results need further investigation, but we are the first to report a beneficial effect of slow-release caffeine and melatonin on physical performances after jet-lag. C1 Inst Med Aerosp, Serv Sante Armees, F-91223 Bretigny Sur Orge, France. NESTEC SA, Ctr Rech Nestle, CH-1000 Lausanne 26, Switzerland. USAF, Res Lab, Brooks AFB, TX 78235 USA. RP Lagarde, D (reprint author), Inst Med Aerosp, Serv Sante Armees, BP 73, F-91223 Bretigny Sur Orge, France. NR 43 TC 24 Z9 24 U1 1 U2 5 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0195-9131 J9 MED SCI SPORT EXER JI Med. Sci. Sports Exerc. PD APR PY 2001 VL 33 IS 4 BP 628 EP 634 PG 7 WC Sport Sciences SC Sport Sciences GA 419UN UT WOS:000167967200018 PM 11283440 ER PT J AU Cation, LJ Lenihan, DJ Gutierrez-Nunez, JJ AF Cation, LJ Lenihan, DJ Gutierrez-Nunez, JJ TI Military graduate medical education in internal medicine: An outcomes study SO MILITARY MEDICINE LA English DT Article ID CARE; PHYSICIANS AB Military graduate medical education has come under increasing scrutiny in recent years as the size of the military medical force declines. To document the outcomes of military graduate medical education in internal medicine, a cohort of Air Force internal medicine residency graduates from Wright-Patterson Medical Center were studied and their residency performance, staff performance, and active duty retention recorded. The study cohort had an outstanding residency performance, as measured by research experience and board certification rate. They also performed well as military staff physicians, receiving numerous individual military medals while holding important administrative and supervisory positions in the military. Finally, the study cohort had a higher than expected active duty retention rate. These findings support the notion that military graduate medical education in internal medicine produces outstanding military internists. C1 Univ Illinois, Coll Med, Dept Med, Peoria, IL 61637 USA. Univ Texas, Med Branch, Galveston, TX 77555 USA. Uniformed Serv Univ Hlth Sci, Dept Med, Andrews AFB, MD 20762 USA. RP Cation, LJ (reprint author), Univ Illinois, Coll Med, Dept Med, 530 NE Glen Oak Ave, Peoria, IL 61637 USA. NR 23 TC 4 Z9 4 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD APR PY 2001 VL 166 IS 4 BP 314 EP 317 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 653CZ UT WOS:000181418800007 PM 11315470 ER PT J AU Clark, N AF Clark, N TI A "silicon eye" using MEMS micromirrors SO MRS BULLETIN LA English DT Article ID SQUARES C1 USAF, Res Lab, Smart Adapt Vis Program, Kirtland AFB, NM 87117 USA. RP Clark, N (reprint author), USAF, Res Lab, Smart Adapt Vis Program, Kirtland AFB, NM 87117 USA. NR 13 TC 4 Z9 4 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 APR PY 2001 VL 26 IS 4 BP 320 EP 324 DI 10.1557/mrs2001.71 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 424MU UT WOS:000168236700024 ER PT J AU Previc, FH Naegele, PD AF Previc, FH Naegele, PD TI Target-tilt and vertical-hemifield asymmetries in free-scan search for 3-D targets SO PERCEPTION & PSYCHOPHYSICS LA English DT Article ID VISUAL-SEARCH; PERFORMANCE; PERCEPTION; ATTENTION; SELECTION; MOVEMENTS; SHAPES; SPACE AB In this study, asymmetries in finding pictorial 3-D targets defined by their tilt and rotation in space were investigated by means of a free-scan search task. In Experiment 1, feature search for cube tilt and rotation, as assessed by a spatial forced-choice task, was slow but still exhibited a characteristic "flat" slope; it was also much faster to upward-tilted cubes and to targets located in the upper half of the search field. Faster search times for cubes and rectangular solids in the upper field, an advantage for upward-tilted cubes, and a strong interaction between target tilt and direction of lighting (upward or downward) for the rectangular solids were all demonstrated in Experiment 2. Finally, an advantage in searching for tilted cubes located in the upper half of the display was shown in Experiment 3, which used a present-absent search task. The results of this study confirm that the upper-field bias in visual search is due mainly to a biased search mechanism and not to the features of the target stimulus or to specific ecological factors. C1 USAF, Res Lab, Brooks AFB, TX 78235 USA. Res & Dev Labs, Culver City, CA USA. RP Previc, FH (reprint author), TASC Inc, 4241 Woodcock Dr,Ste B100, San Antonio, TX 78228 USA. NR 20 TC 19 Z9 20 U1 0 U2 1 PU PSYCHONOMIC SOC INC PI AUSTIN PA 1710 FORTVIEW RD, AUSTIN, TX 78704 USA SN 0031-5117 J9 PERCEPT PSYCHOPHYS JI Percept. Psychophys. PD APR PY 2001 VL 63 IS 3 BP 445 EP 457 DI 10.3758/BF03194411 PG 13 WC Psychology; Psychology, Experimental SC Psychology GA 437LU UT WOS:000168993800006 PM 11414132 ER PT J AU Bimberg, D Grundmann, M Ledentsov, NN Mao, MH Ribbat, C Sellin, R Ustinov, VM Zhukov, AE Alferov, ZI Lott, JA AF Bimberg, D Grundmann, M Ledentsov, NN Mao, MH Ribbat, C Sellin, R Ustinov, VM Zhukov, AE Alferov, ZI Lott, JA TI Novel infrared quantum dot lasers: Theory and reality SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT International Conference on Semiconductor Quantum Dots (QD2000) CY JUL 31-AUG 03, 2000 CL TECHN UNIV MUNICH, MUNICH, GERMANY HO TECHN UNIV MUNICH ID THRESHOLD CURRENT-DENSITY; SURFACE-EMITTING LASER; MU-M EMISSION; OPTICAL-PROPERTIES; ROOM-TEMPERATURE; DIFFERENTIAL GAIN; GAAS SUBSTRATE; ZNSE MATRIX; DIODE-LASER; ISLANDS AB Semiconductor heterostructures a with size quantization of carriers in all three directions, or quantum dots (QDs), open a new era in device engineering. An important breakthrough occurred when the self-organised growth approach had been refined to such an extent, that defect-free QDs made with these technique exhibited properties predicted for zero-dimensional structures. Their practical application in devices, first of all lasers, became possible. When used for active layers in injection lasers differential gain is strongly increased potentially providing improved dynamic properties. The cut-off frequencies larger than 10 GHz are presently demonstrated The saturation material gain is as high as 15 x 10(4) cm(-1) as compared to QW values of about 3 x 10(3) cm(-1). The wavelength dependence of gain is best described by Master equations of microstates. High internal (> 96%) and differential (70%) efficiencies at 300 K and output power up to 3 W are realized now for QD lasers emitting in the 0.94-1.15 mum range. Transparency current density of 18 A/cm(2) has been recently demonstrated at 1.15 mum. GaAs-based QD lasers emit near 1.3 mum with J(th) = 70 A/cm(2) (L = 1.9 mm, 300 K) and CW output power of similar to3 W In narrow (7 mum) stripes almost chirp-free operation and relaxation oscillations at 2.4 GHz (L = 300 mum) are manifested. Differential efficiency is 55% and internal losses are 1.5 cm(-1). 1.3 mum GaAs-based QD VCSELs (300 K, I-th = 1.8 mA, eta (diff) > 40%) are realized. C1 Tech Univ Berlin, Inst Festkorperphys, D-10623 Berlin, Germany. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Bimberg, D (reprint author), Tech Univ Berlin, Inst Festkorperphys, Hardenbergstr 36, D-10623 Berlin, Germany. EM bimberg@physik.tu-berlin.de RI Zhukov, Alexey/A-5523-2014; Ustinov, Viktor/J-3545-2013; Grundmann, Marius/D-4229-2012 OI MAO, MING-HUA/0000-0002-3972-5039; Zhukov, Alexey/0000-0002-4579-0718; Grundmann, Marius/0000-0001-7554-182X NR 59 TC 36 Z9 36 U1 1 U2 8 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD APR PY 2001 VL 224 IS 3 BP 787 EP 796 DI 10.1002/(SICI)1521-3951(200104)224:3<787::AID-PSSB787>3.0.CO;2-M PG 10 WC Physics, Condensed Matter SC Physics GA 427XU UT WOS:000168432100034 ER PT J AU Yepez, J AF Yepez, J TI Quantum lattice-gas model for computational fluid dynamics SO PHYSICAL REVIEW E LA English DT Article ID SCHRODINGER-EQUATION; CELLULAR-AUTOMATA; HYDRODYNAMICS; MECHANICS AB Quantum-computing ideas are applied to the practical and ubiquitous problem of fluid dynamics simulation. Hence, this paper addresses two separate areas of physics: quantum mechanics and fluid dynamics (or specifically, the computational simulation of fluid dynamics). The quantum algorithm is called a quantum lattice gas. An analytical treatment of the microscopic quantum lattice-gas system is carried out to predict its behavior at the mesoscopic scale. At the mesoscopic scale, a lattice Boltzmann equation with a nonlocal collision term that depends on the entire system wave function, governs the dynamical system. Numerical results obtained from an exact simulation of a one-dimensional quantum lattice model are included to illustrate the formalism. A symbolic mathematical method is used to implement the quantum mechanical model on a conventional workstation. The numerical simulation indicates that classical viscous damping is not present in the one-dimensional quantum lattice-gas system. C1 USAF, Res Lab, Bedford, MA 01731 USA. RP Yepez, J (reprint author), USAF, Res Lab, Bedford, MA 01731 USA. NR 22 TC 35 Z9 35 U1 0 U2 4 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 APR PY 2001 VL 63 IS 4 AR 046702 DI 10.1103/PhysRevE.63.046702 PN 2 PG 18 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 424CT UT WOS:000168215100083 PM 11308976 ER PT J AU Park, SY Interrante, LV Farmer, BL AF Park, SY Interrante, LV Farmer, BL TI The structure of poly(di-n-propylsilylenemethylene) SO POLYMER LA English DT Article DE poly(di-n-propylsilylenemethylene); X-ray diffraction; conformation ID SOLID-STATE; CONFORMATION; POLYMER AB The structure of poly(di-n-propylsilylenene thylene) (PDPrSM) has been studied by X- ray diffraction, electron diffraction and molecular modeling. The fiber X-ray data and the electron diffraction pattern of single crystals show that PDPrSM has triclinic symmetry with unit cell parameters a = 10.52 Angstrom, b = 8.66 Angstrom. c = 4.86 Angstrom,= 78.4 degrees, beta = 100.0 degrees and gamma = 98.2 degrees .The fiber repeat, 4.86 Angstrom, indicates an all-gauche conformation in the main chain, giving a 4(1) helical structure. Ab initio and semi-empirical energy calculations show that with attachment of n-alkyl side chains an all-gauche conformation for the main chain gives the lowest energy. This is in contrast to the unsubstituted polymer. poly(silaethylene), which has a minimum energy for the all-trans conformation. The all-gauche conformation of the main chain of PDPrSM relieves the steric hindrance between side chains found in the all-trans conformation. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. Rensselaer Polytech Inst, Dept Chem, Troy, NY 12180 USA. RP Farmer, BL (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 14 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD APR PY 2001 VL 42 IS 9 BP 4253 EP 4260 DI 10.1016/S0032-3861(00)00766-7 PG 8 WC Polymer Science SC Polymer Science GA 403NY UT WOS:000167050400033 ER PT J AU Park, SY Interrante, LV Farmer, BL AF Park, SY Interrante, LV Farmer, BL TI The structures of poly(di-n-alkylsilylenemethylene)s SO POLYMER LA English DT Article DE electron diffraction; poly(di-n-alkylsilylenemethylene)s; conformation ID CONFORMATION; POLYMER AB The structure of poly(diethylsilylenemethylene) (PDESM), poly(di-n-butylsilylenemethylene) (PDESM), poly(di-n-pentylsilylenemethyl- ene) (PDPeSM) and poly(di-n-hexylsilylenemethylene) (PDHSM) have been studied using X-ray and electron diffraction methods. The structure of poly(di-n-propylsilylenemethylene) (PDPrSM) has been studied and reported in a separate paper. PDBSM, PDPrSM, PDPeSM and PDHSM all have similar packing with a two dimensional monoclinic ab-projection of the unit cell. PDESM with the shortest alkyl side chain, has a nearly orthorhombic unit cell (gamma* = similar to 88 degrees) containing two chains (four repeat units), one at the corner and the second nearly in the center of the ab-projection of the unit cell. The backbone conformation of each of these polysilylenemethylenes (PSMs) is all-gauche, giving them a 4(1) helical structure. The length of the alkyl side chains affects the packing without changing the backbone conformation. (C) 2001 Published by Elsevier Science Ltd. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. Rensselaer Polytech Inst, Dept Chem, Troy, NY 12180 USA. RP Farmer, BL (reprint author), USAF, Res Lab, Mat & Mfg Directorate, 2941 P St,Suite I, Wright Patterson AFB, OH 45433 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 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 APR PY 2001 VL 42 IS 9 BP 4261 EP 4269 DI 10.1016/S0032-3861(00)00772-2 PG 9 WC Polymer Science SC Polymer Science GA 403NY UT WOS:000167050400034 ER PT J AU Pirzada, M Grimes, RW Minervini, L Maguire, JF Sickafus, KE AF Pirzada, M Grimes, RW Minervini, L Maguire, JF Sickafus, KE TI Oxygen migration in A(2)B(2)O(7) pyrochlores SO SOLID STATE IONICS LA English DT Article DE pyrochlore; oxygen transport; defect energies; atomistic simulation; activation energies ID GADOLINIUM ZIRCONATE; OXIDE PYROCHLORES; SOLID-SOLUTIONS; CONDUCTIVITY; DISORDER; FLUORITE; ION; STABILITY AB Atomic scale computer simulation has been used to predict activation energies for oxygen migration. In total, 54 compounds with the A(2)B(2)O(7) pyrochlore structure were simulated. In each case, oxygen migration was assumed to proceed via an oxygen vacancy mechanism with oxygen ions hopping between 48f sites. For some compounds the unoccupied 8a interstitial position played an important role in the migration mechanism. The results were analyzed using a contour map of activation energy versus A cation radius along the ordinate and B cation radius along the abscissa. This identified areas of similar cation radii, which exhibit lower activation energy. Results compare favourably with available experimental data. (C) 2001 Elsevier Science B.V, All rights reserved. C1 Imperial Coll, Dept Mat, London SW7 2BP, England. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USAF, Res Lab, MLMR, AFRL, Wright Patterson AFB, OH 45433 USA. RP Imperial Coll, Dept Mat, London SW7 2BP, England. EM r.grimes@ic.ac.uk NR 29 TC 139 Z9 140 U1 3 U2 44 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 EI 1872-7689 J9 SOLID STATE IONICS JI Solid State Ion. PD APR PY 2001 VL 140 IS 3-4 BP 201 EP 208 DI 10.1016/S0167-2738(00)00836-5 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 439EU UT WOS:000169098500002 ER PT J AU Hedrick, A Barbarino, R Roll, F Reeve, E AF Hedrick, A Barbarino, R Roll, F Reeve, E TI Learning from each other: Adjusting nutritional supplements based on new NCAA guidelines SO STRENGTH AND CONDITIONING JOURNAL LA English DT Editorial Material C1 USAF Acad, Colorado Springs, CO 80840 USA. Univ Delaware Athlet, Newark, DE 19716 USA. Kansas State Univ, Manhattan, KS 66506 USA. Ohio Univ, Athens, OH 45701 USA. RP Hedrick, A (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ALLEN PRESS INC PI LAWRENCE PA 810 E 10TH ST, LAWRENCE, KS 66044 USA SN 1073-6840 J9 STRENGTH COND J JI Strength Cond. J. PD APR PY 2001 VL 23 IS 2 BP 53 EP 54 PG 2 WC Sport Sciences SC Sport Sciences GA 423GM UT WOS:000168167100010 ER PT J AU Steiner, NK Gans, CP Kosman, C Bradshaw, D Koester, R Menchaca, EM Mitton, W Ng, J Hartzman, RJ Hurley, CK AF Steiner, NK Gans, CP Kosman, C Bradshaw, D Koester, R Menchaca, EM Mitton, W Ng, J Hartzman, RJ Hurley, CK TI New alleles in the B44 family including B*44022, B*44032, B*4411, B*4420, B*4421, B*4424, and B*8301 SO TISSUE ANTIGENS LA English DT Article DE DNA sequencing; HLA-B ID HLA-B ALLELES; DIVERSITY; ANTIGENS AB Seven new HLA-B locus alleles have been described. B*44022 and B*44032 are silent substitutions altering known alleles. B*4411 carries a unique Bw4-like epitope. B*4420, B*4421, and B*4424 carry new combinations of motifs previously observed in other alleles. B*8301 appears to be the result of the replacement of exon 2 from B*4402 with exon 2 from B*5603. C1 Georgetown Univ, Med Ctr, Dept Oncol Microbiol & Immunol, Washington, DC 20007 USA. Georgetown Univ, Med Ctr, Dept Pediat, Washington, DC 20007 USA. USN, Med Res Ctr, CW Bill Young Marrow Donor Program, Kensington, MD USA. Lab Corp Amer, Burlington, NC USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Hurley, CK (reprint author), Georgetown Univ, Med Ctr, Dept Oncol Microbiol & Immunol, E404 Res Bldg,3970 Reservoir Rd NW, Washington, DC 20007 USA. NR 12 TC 8 Z9 8 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0001-2815 J9 TISSUE ANTIGENS JI Tissue Antigens PD APR PY 2001 VL 57 IS 4 BP 376 EP 379 DI 10.1034/j.1399-0039.2001.057004376.x PG 4 WC Cell Biology; Immunology; Pathology SC Cell Biology; Immunology; Pathology GA 440RG UT WOS:000169187600016 PM 11380952 ER PT J AU Toth, DK Saba, CS Klenke, CJ AF Toth, DK Saba, CS Klenke, CJ TI Minisimulator for evaluating high-temperature candidate lubricants: part I - Method development SO TRIBOLOGY TRANSACTIONS LA English DT Article DE turbine engines; polyphenyl ether (PPE); bearings AB A new turbine engine lubrication system simulator was developed for assessing coking performance of high-temperature fluids of limited quantity. The system, constructed from corrosion-resistant material, can use less than one liter of fluid to lubricate two 30-mm bore, angular contact ball bearings under a 100-ksi Hertz stress. Testing has been done at bearing speed's of 10,000 rpm with bearing temperatures as high as 360 degreesC for polyphenyl ether fluids. Oil samples are periodically drawn from the heated lubricant sump to measure viscosity changes. A demerit system was used to rate the severity of deposits formed on test head components. To help ensure repeatable test results, modifications were made to the test head assembly to improve temperature control of all critical sections. Initial tests of polyphenyl ether at 300 degreesC bulk oil and 360 degreesC bearing temperatures have shown that their deposit tendency could be characterized under dynamic conditions. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. AF Mat Command, Wright Lab, Aero Porp & Power Directorate, Wright Patterson AFB, OH 45433 USA. RP Toth, DK (reprint author), Univ Dayton, Res Inst, Dayton, OH 45469 USA. NR 4 TC 1 Z9 1 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 APR PY 2001 VL 44 IS 2 BP 277 EP 283 DI 10.1080/10402000108982459 PG 7 WC Engineering, Mechanical SC Engineering GA 417NL UT WOS:000167841000022 ER PT J AU Loraine, GA AF Loraine, GA TI Effects of alcohols, anionic and nonionic surfactants on the reduction of PCE and TCE by zero-valent iron SO WATER RESEARCH LA English DT Article DE zero-valent iron; surfactants; TCE; PCE; cosolvents ID ORGANIC CONTAMINANTS; CATIONIC SURFACTANT; TETRACHLOROETHYLENE; TRICHLOROETHYLENE; SOLUBILIZATION; SORPTION; AQUIFER; COMPLEX; SYSTEM; SOIL AB The effects of surfactants, sodium dodecyl sulfate (SDS) and Triton X-a00 (TX), and alcohols (methanol, ethanol, and propanol) on the dehalogenation of TCE and PCE by zero-valent iron were examined. Surface concentrations of PCE and TCE on the iron were dependent on aqueous surfactant concentrations. At concentrations above the CMC, sorbed halocarbon concentrations declined and concentrations associated with solution phase micelles increased. The anionic surfactant SDS ([SDS] 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, AFRL, LMQR, Tyndall AFB, FL 32403 USA. RP Loraine, GA (reprint author), San Diego State Univ, Dept Civil & Environm Engn, 5500 Campanile Dr, San Diego, CA 92182 USA. NR 25 TC 53 Z9 59 U1 6 U2 26 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0043-1354 J9 WATER RES JI Water Res. PD APR PY 2001 VL 35 IS 6 BP 1453 EP 1460 DI 10.1016/S0043-1354(00)00422-X PG 8 WC Engineering, Environmental; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA 413NH UT WOS:000167617900010 PM 11317892 ER PT J AU Schwartz, M Berry, RJ AF Schwartz, M Berry, RJ TI Ab initio investigation of substituent effects on bond dissociation enthalpies in siloxanes and silanols SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE siloxane; silanol; bond dissociation enthalpy; quantum mechanics; Gaussian-2 ID H BOND; DISILOXANE; DENSITY; ENERGY; MOLECULES AB Silicon-oxygen Bond Dissociation Enthalpies (BDEs) were computed at the Gaussian-2 level of theory (using isodesmic reactions) for a series of substituted siloxanes and silanols, SiRnH3-nOSiH3 and SiRnH3-nOH, R = F, Cl, Br, OH, CH3. If was found that all substituents induce substantial increases in the bond strengths of the adjacent Si-O bonds. The magnitude of the effect roughly parallels the substituent electronegativity, and can be explained on the basis of an inductive increase of the bond polarity. Three of the substituents, fluorine, chlorine and hydroxyl groups, also cause relatively large increases in the dissociation enthalpies of the remote silicon-oxygen bond in the siloxanes. This latter effect was found to correlate negatively with SiO . bond length variations in the siloxy radicals. This correlation provides evidence that the bond enthalpy increases of the remote silicon-oxygen bonds arises from either inductive effects or pi -backbonding, either of which would destabilize the radical center. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ N Texas, Dept Chem, Denton, TX 76203 USA. USAF, Res Lab, Mat & Mfg Directorate, MLBP, Wright Patterson AFB, OH 45433 USA. RP Schwartz, M (reprint author), Univ N Texas, Dept Chem, Denton, TX 76203 USA. NR 27 TC 10 Z9 11 U1 2 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD MAR 30 PY 2001 VL 538 BP 9 EP 17 DI 10.1016/S0166-1280(00)00643-6 PG 9 WC Chemistry, Physical SC Chemistry GA 408UW UT WOS:000167346700002 ER PT J AU Zhou, W Mark, JE Unroe, MR Arnold, FE AF Zhou, W Mark, JE Unroe, MR Arnold, FE TI Toughening of a high-temperature polymer by the sol-gel, in situ generation of a rubbery silica-siloxane phase SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE high-temperature polymers; poly(biphenyl ether triphenyl phosphate); sol-gel process; sulfonation; elongation; ultimate properties; toughening; N,N-diethyl-aminopropyltrimethoxysilane AB A phenyl ether phenyl phosphate polymer, specifically poly(biphenyl ether triphenyl phosphate), was modified to increase its tractability and to improve its toughness. The first goal was achieved by increasing its solubility by sulfonation of the chain, and the second, by the in situ generation of a rubbery phase. This phase was generated by a modification of the usual sol-gel reaction (which usually generates a hard silicalike material by the hydrolysis of a tetrafunctional organosilicate). In this case, a difunctional silicate was included, thus introducing some softening organic groups into the dispersed phase. A bonding agent, N,N-diethylaminopropyltrimethoxysilane, was also included to improve the bonding between the two phases in this organic-inorganic composite. As expected, the glass transition temperatures generally increased slightly upon sulfonation, but decreased significantly upon introduction of the rubbery phase. Most important, the toughness of the polymer was successfully increased with, for example, only 8 wt % of the rubbery phase, quadrupling extensibility to 20 % and markedly increasing the toughness. (C) 2001 John Wiley & Sons, Inc. C1 Univ Cincinnati, Dept Chem, Cincinnati, OH 45221 USA. Univ Cincinnati, Polymer Res Ctr, Cincinnati, OH 45221 USA. USAF, Polymer Branch, AFRL, MLBP, Wright Patterson AFB, OH 45433 USA. RP Mark, JE (reprint author), Univ Cincinnati, Dept Chem, Cincinnati, OH 45221 USA. NR 19 TC 11 Z9 11 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD MAR 28 PY 2001 VL 79 IS 13 BP 2326 EP 2330 DI 10.1002/1097-4628(20010328)79:13<2326::AID-APP1040>3.0.CO;2-A PG 5 WC Polymer Science SC Polymer Science GA 397LY UT WOS:000166698200002 ER PT J AU Saxler, A Look, DC Elhamri, S Sizelove, J Mitchel, WC Sung, CM Park, SS Lee, KY AF Saxler, A Look, DC Elhamri, S Sizelove, J Mitchel, WC Sung, CM Park, SS Lee, KY TI High mobility in n-type GaN substrates SO APPLIED PHYSICS LETTERS LA English DT Article ID SEMICONDUCTORS; DIODES AB High peak electron mobilities were observed in freestanding c-plane GaN layers. Two well-defined electrical layers, a low mobility degenerate interface layer, and a high mobility nondegenerate bulk layer, were present in these samples. The carrier concentrations and mobilities for the layers were extracted using two methods: (1) magnetic field dependent Hall effect analysis; and (2) a simple two layer Hall model with the assumption that one of the layers is degenerate. The electron Hall mobility of the bulk layer is found to peak at nearly 8000 cm(2)/V s at low temperature using the magnetic field dependent Hall effect analysis. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Univ Massachusetts, Ctr Adv Mat, Lowell, MA 01854 USA. Samsung Adv Inst Technol, Suwon, South Korea. Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. Univ Dayton, Dept Phys, Dayton, OH 45469 USA. RP Saxler, A (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 9 TC 18 Z9 18 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 26 PY 2001 VL 78 IS 13 BP 1873 EP 1875 DI 10.1063/1.1348304 PG 3 WC Physics, Applied SC Physics GA 415VJ UT WOS:000167744000024 ER PT J AU Zhang, H Wang, XM Zelmon, DE Teo, BK AF Zhang, H Wang, XM Zelmon, DE Teo, BK TI Synthesis and structure of [(DB24C8)Na][Cd(SCN)(3)]. Formation of a novel linear Cd center dot center dot center dot Cd center dot center dot center dot Cd chain with a mer-CdN3S3 coordination configuration and a new coiled [(DB24C8)Na](+) cation SO INORGANIC CHEMISTRY LA English DT Article ID ORGANIC SPACERS; CRYSTAL; DESIGN; COMPLEXES; TRIS(THIOCYANATO)CADMATES(II); <(12C4)(2)CD>; CHEMISTRY; POLYMERS; CRITERIA AB We report herein a novel coordination solid, [(DB24C8)Na] [Cd(SCN)(3)] (6) (DB24C8) denotes dibenzo-24-crown-8, which exhibits a new type of [Cd(SCN)3(-)](infinity) chain with two unusual stereochemical characteristics: (1) a mer-CdN3S3 coordination and (2) a linear Cd chain with a Cd . . . Cd . . . Cd angle of 180 degrees. In addition, the [(DB24C8)Na](+) monocation adopts a new structural type-a coiled structure-for the combination of crown ether DB24C8 and alkali metal Na+. The title compound crystallizes in a monoclinic unit cell of C2/e space group symmetry with lattice parameters a = 16.110(8) Angstrom, b = 20.380(5) Angstrom, 11.01(1) Angstrom, beta = 119.87(3)degrees, and Z = 4. The arrangement of the [Cd(SCN)(3)(-)](infinity) chains in the crystal lattice in the title compound is approximately hexagonal, creating triangular channels which are filled with [(DB23C8)Na](+) monocations. It was previously reasoned by us that the coiled [(DB24C8)Na](+) monocation, which lacks inversion or mirror symmetries, should enhance the tendency for the formation of the noncentrosymmetric space group of the title crystal, making it a potential second-order nonlinear optical crystal. Interestingly, however: the title compound crystallizes in a centrosymmetric space group (C2/c) and gives rise to no second harmonic generation (SHG). Previously known [Cd(SCN)(3)(-)](infinity) chains adopt fac-CdN3S3 coordination and a zigzag Cd chain configuration with a Cd . . . Cd . . Cd angle of 165 degrees. The zigzag chains can align in either parallel or antiparallel fashion, resulting in efficient or no SHG effects, respectively. The linear Cd . . . Cd . . . Cd chain configuration observed in the title compound, on the other hand, makes it indistinguishable between parallel and antiparallel alignments. It is concluded that, to ensure the formation of noncentrosymmetric space groups, it is necessary to employ optically pure chiral cations as spacers and/or controllers. Furthermore, to enhance the nonlinear optical responses, [Cd(SCN)(3)(-)](infinity) chains with fac-CdN3S3 coordination and parallel alignments of the zigzag Cd chains should be used. C1 USAF, Res Lab, MLPO, Mat Directorate, Wright Patterson AFB, OH 45433 USA. Univ Illinois, Dept Chem MC 111, Chicago, IL 60607 USA. RP Zhang, H (reprint author), USAF, Res Lab, MLPO, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 35 TC 27 Z9 28 U1 3 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAR 26 PY 2001 VL 40 IS 7 BP 1501 EP 1507 DI 10.1021/ic0001762 PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 413AT UT WOS:000167588300016 PM 11261957 ER PT J AU Jones, BS Lynn, WF Stone, MO AF Jones, BS Lynn, WF Stone, MO TI Thermal modeling of snake infrared reception: Evidence for limited detection range SO JOURNAL OF THEORETICAL BIOLOGY LA English DT Article ID ULTRASTRUCTURE; PREY AB For more than 40 years, information has circulated with regard to the sensitivity of infrared pit organs in both bold and crotaline snakes (pythons and pit vipers, respectively). The most often quoted sensitivity is 0.003 degreesC and this value is based on the work of Bullock and co-workers (1956). Missing from previous work was a quantitative model of radiation transfer that would report sensitivity not in terms of degrees Celsius, but rather sensing distance. Since prey detection is often cited as the function of the infrared pit organ, quantification of this sensing distance seemed to be an important value that was missing from the literature. In this paper, we model the radiation transfer process from a 37 degreesC object, i.e. warm-blooded prey, to an infrared pit organ. The model tries to answer a very basic question-at what distance does the thermal signature of a 37 degreesC object blend into the background for a non-imaging biological infrared sensor? The output of the model, the sensing distance, is of particular interest in comparing biological infrared sensors to current semiconductor-based infrared (IR) detectors-largely because of inappropriate comparisons between the temperature sensitivity of IR snake reception and imaging IR cameras. The purpose of the presented work to make more appropriate comparisons, i.e. sensing distance. This sensing distance output indicates an extremely short detection distance (<5 cm)-contradictory to what is observed experimentally. This dichotomy raises further questions regarding how the biological system amplifies this weak signal. <(c)> 2001 Academic Press. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Veridian Engn, Dayton, OH 45431 USA. Wright State Univ, Dept Biomed Engn, Dayton, OH 45435 USA. RP Stone, MO (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 21 TC 9 Z9 10 U1 0 U2 9 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-5193 J9 J THEOR BIOL JI J. Theor. Biol. PD MAR 21 PY 2001 VL 209 IS 2 BP 201 EP 211 DI 10.1006/jtbi.2000.2256 PG 11 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 419HT UT WOS:000167943800008 PM 11401462 ER PT J AU Tyo, JS Turner, TS AF Tyo, JS Turner, TS TI Variable-retardance, Fourier-transform imaging spectropolarimeters for visible spectrum remote sensing SO APPLIED OPTICS LA English DT Article ID SCATTERING MEDIA; TARGET DETECTION; SPECTROMETER; IMAGER AB An imaging, variable-retardance, Fourier-transform spectropolarimeter is presented that is capable of creating spectropolarimetric images of scenes with independent characterization of spatial, spectral, and polarimetric information. The device has a spectral resolution of similar to 225 cm(-1), making it truly hyperspectral in nature. Images of canonical targets such as spheres and cylinders obtained in a laboratory setup are presented. The results demonstrate the capability of developing systems to collect spectropolarimetric data of field images by use of the concept of pushbroom scanning and serial collection of polarimetric information. Further development of a parallelized collection strategy would allow the collection of near-real-time images of real-world targets. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Tyo, JS (reprint author), USN, Postgrad Sch, Dept Elect & Comp Engn, 589 Dyer Rd, Monterey, CA 93943 USA. EM tyo@ieee.org NR 16 TC 44 Z9 45 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD MAR 20 PY 2001 VL 40 IS 9 BP 1450 EP 1458 DI 10.1364/AO.40.001450 PG 9 WC Optics SC Optics GA 413RX UT WOS:000167626700022 PM 18357136 ER PT J AU Semiatin, SL Jata, KV Uchic, MD Berbon, PB Matejczyk, DE Bampton, CC AF Semiatin, SL Jata, KV Uchic, MD Berbon, PB Matejczyk, DE Bampton, CC TI Plastic flow and fracture behavior of an Al-Ti-Cu nanocomposite SO SCRIPTA MATERIALIA LA English DT Article DE nanocomposite; plasticity; brittle fracture ID SUPERPLASTICITY; DEFORMATION C1 USAF, Res Lab, MLLM, Wright Patterson AFB, OH 45433 USA. Rockwell Int Sci Ctr, Thousand Oaks, CA 91358 USA. Rocketdyne Div, Canoga Park, CA 91309 USA. RP Semiatin, SL (reprint author), USAF, Res Lab, MLLM, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 12 TC 29 Z9 31 U1 0 U2 8 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 MAR 16 PY 2001 VL 44 IS 3 BP 395 EP 400 DI 10.1016/S1359-6462(00)00612-6 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 416GD UT WOS:000167771200002 ER PT J AU Kumar, B Scanlon, L Marsh, R Mason, R Higgins, R Baldwin, R AF Kumar, B Scanlon, L Marsh, R Mason, R Higgins, R Baldwin, R TI Structural evolution and conductivity of PEO : LiBF4-MgO composite electrolytes SO ELECTROCHIMICA ACTA LA English DT Article; Proceedings Paper CT 7th International Symposium on Polymer Electrolytes (ISPE-7) CY AUG 06-11, 2000 CL NOOSA, AUSTRALIA DE polymer-ceramic; electrolyte; lithium-ion; conductivity; structure ID POLYMER ELECTROLYTES; BATTERIES AB This paper explores and proposes a structure-conductivity correlation in the PEO:LiBF4-MgO composite electrolyte system. The proposed correlation is derived from interpretations of DSC and conductivity measurements. Thermal cycling in the 0-100 degreesC range yields an amorphous polymer structure believed to be beneficial for enhanced conductivity. The proposed roles of MgO are to depress the PEO melting temperature and retard the kinetics of its crystallization. A resistivity relaxation or conductivity enhancement below the melting temperature of PEO (68 degreesC) occurs, which appears to be a characteristic of these electrolytes and related to an interaction of dipoles associated with polymer chains and MgO. A higher concentration (similar or equal to 30%) of MgO leads to its segregation and reduction in conductivity resulting from crystallization of PEG. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. USAF, Res Lab, Prop Directorate, Wright Patterson AFB, OH 45433 USA. Eagle Picher Technol LLC, Joplin, MO 64802 USA. NASA, Glenn Res Ctr, Cleveland, OH 44135 USA. RP Kumar, B (reprint author), Univ Dayton, Res Inst, 300 Coll Pk,KL 501, Dayton, OH 45469 USA. NR 7 TC 67 Z9 71 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD MAR 15 PY 2001 VL 46 IS 10-11 BP 1515 EP 1521 DI 10.1016/S0013-4686(00)00747-7 PG 7 WC Electrochemistry SC Electrochemistry GA 418ZB UT WOS:000167924000017 ER PT J AU Gustafson, SC Hale, TB Claypoole, RL AF Gustafson, SC Hale, TB Claypoole, RL TI Competitively evolved probability densities for signal interpolation SO ELECTRONICS LETTERS LA English DT Article AB A procedure is described and illustrated enabling efficient estimation of the relative probabilities of unknown signal values located between given signal values. A simple competition among the smoothest possibly interpolating functions evolves the probability densities governing this estimation. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Gustafson, SC (reprint author), USAF, Inst Technol, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 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 MAR 15 PY 2001 VL 37 IS 6 BP 396 EP 398 DI 10.1049/el:20010223 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA 418WH UT WOS:000167916800047 ER PT J AU Baldwin, JB Tutt, RC LoRusso, FJ Hiers, PL Ivan, DJ Johnson, DA Smith, RE Thompson, B AF Baldwin, JB Tutt, RC LoRusso, FJ Hiers, PL Ivan, DJ Johnson, DA Smith, RE Thompson, B TI A prospective evaluation of the effect of high altitude exposure after PRK. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 USAF, Sch Aerosp Med, Aeromed Consultat Svc, Brooks AFB, TX 78235 USA. USAF, Res Lab, Brooks AFB, TX USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Conceptual Mindworks, San Antonio, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 2001 VL 42 IS 4 SU S MA 2647 BP S490 EP S490 PG 1 WC Ophthalmology SC Ophthalmology GA 427EP UT WOS:000168392102616 ER PT J AU Glickman, RD Howell, RM Rockwell, BA Kumar, N Noojin, G AF Glickman, RD Howell, RM Rockwell, BA Kumar, N Noojin, G TI DNA damage in cultured RPE cells produced by laser-induced multiphoton absorption. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Univ Texas, Hlth Sci Ctr, Dept Ophthalmol, San Antonio, TX 78284 USA. Univ Texas, Hlth Sci Ctr, Div Radiol Sci, San Antonio, TX 78284 USA. USAF, Res Lab, Brooks AFB, TX USA. Litton TASC Inc, San Antonio, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 2001 VL 42 IS 4 SU S MA 4039 BP S754 EP S754 PG 1 WC Ophthalmology SC Ophthalmology GA 427EP UT WOS:000168392104002 ER PT J AU Goodman, RL Holck, DE Ng, JD Kikkawa, DO Piest, KL Otto, R Soparkar, CN Patrinely, JR AF Goodman, RL Holck, DE Ng, JD Kikkawa, DO Piest, KL Otto, R Soparkar, CN Patrinely, JR TI Orbital reconstruction using custom-made orbital alloplastic porous polyethylene implants. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Dept Ophthalmol, San Antonio, TX 78236 USA. Oregon Hlth Sci Ctr, Casey Eye Inst, Oculoplast Serv, Portland, OR 97201 USA. Univ Calif San Diego, Dept Ophthalmol, San Diego, CA USA. Ophthalm Past Surg, San Antonio, TX USA. Univ Texas, Dept Otolarhinol, San Antonio, TX USA. Plast Eye Surg Associates, Houston, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 2001 VL 42 IS 4 SU S MA 1851 BP S342 EP S342 PG 1 WC Ophthalmology SC Ophthalmology GA 427EP UT WOS:000168392101821 ER PT J AU Holck, DE Ng, JD Foster, JA Dutton, JJ DeBacker, CM Cho, R Goodman, R AF Holck, DE Ng, JD Foster, JA Dutton, JJ DeBacker, CM Cho, R Goodman, R TI Temporalis muscle transfer flaps in the treatment of the contracted orbit. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, Dept Ophthalmol, San Antonio, TX 78236 USA. Brooke Army Med Ctr, San Antonio, TX USA. Cleveland Clin Fdn, Cleveland, OH 44195 USA. Atlantic Eye & Face Ctr, Cary, NC USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 2001 VL 42 IS 4 SU S MA 1842 BP S341 EP S341 PG 1 WC Ophthalmology SC Ophthalmology GA 427EP UT WOS:000168392101812 ER PT J AU Kugler, L Foster, JA Perry, JD Sputh, E Holck, DEE AF Kugler, L Foster, JA Perry, JD Sputh, E Holck, DEE TI Professed human pricardium barrier for gold weight implantation. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Cleveland Clin Fdn, Cole Eye Inst, Cleveland, OH 44195 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 2001 VL 42 IS 4 SU S MA 1822 BP S337 EP S337 PG 1 WC Ophthalmology SC Ophthalmology GA 427EP UT WOS:000168392101792 ER PT J AU Lane, RG Kerrison, JB Lounsbury, D Schatz, M Engler, RM AF Lane, RG Kerrison, JB Lounsbury, D Schatz, M Engler, RM TI Optic neuritis following anthrax vaccination. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Walter Reed Army Med Ctr, Washington, DC 20307 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 2001 VL 42 IS 4 SU S MA 1757 BP S326 EP S326 PG 1 WC Ophthalmology SC Ophthalmology GA 427EP UT WOS:000168392101727 ER PT J AU Toth, CA McCall, MN Winter, KP Stolarski, DJ Cain, CP Noojin, GD Thomas, R Rockwell, BA AF Toth, CA McCall, MN Winter, KP Stolarski, DJ Cain, CP Noojin, GD Thomas, R Rockwell, BA TI Histopathology of sub-50 femtosecond near-infrared pulsed laser retinal lesions. SO INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE LA English DT Meeting Abstract C1 Duke Univ, Med Ctr, Dept Ophthalmol, Durham, NC 27710 USA. Duke Univ, Dept Biomed Engn, Durham, NC 27706 USA. TASC Inc, San Antonio, TX USA. USAF, Res Lab, Brooks AFB, TX USA. RI toth, cynthia/F-5614-2011 NR 0 TC 0 Z9 0 U1 0 U2 0 PU ASSOC RESEARCH VISION OPHTHALMOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0146-0404 J9 INVEST OPHTH VIS SCI JI Invest. Ophthalmol. Vis. Sci. PD MAR 15 PY 2001 VL 42 IS 4 SU S MA 3751 BP S696 EP S696 PG 1 WC Ophthalmology SC Ophthalmology GA 427EP UT WOS:000168392103714 ER PT J AU Hemmer, PR Turukhin, AV Shahriar, MS Musser, JA AF Hemmer, PR Turukhin, AV Shahriar, MS Musser, JA TI Raman-excited spin coherences in nitrogen-vacancy color centers in diamond SO OPTICS LETTERS LA English DT Article ID ELECTROMAGNETICALLY INDUCED TRANSPARENCY; N-V CENTER; GROUND-STATE; STORAGE AB Raman-excited spin coherences were experimentally observed in nitrogen-vacancy (N-V) diamond color centers by means of nondegenerate four-wave mixing and electromagnetically induced transparency. The maximal absorption suppression was found to be 17%, which corresponds to 70% of what is possible given the random geometric orientation of the N-V center in diamond. In the context of quantum computing in solids, this level of transparency represents efficient preparation of quantum bits, as well as the ability to perform arbitrary single-quantum-bit rotations. (C) 2001 Optical Society of America. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. MIT, Elect Res Lab, Cambridge, MA 02139 USA. Texas A&M Univ, College Stn, TX 77843 USA. RP Hemmer, PR (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. RI Shahriar, Selim/B-7270-2009 NR 17 TC 82 Z9 83 U1 0 U2 9 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 MAR 15 PY 2001 VL 26 IS 6 BP 361 EP 363 DI 10.1364/OL.26.000361 PG 3 WC Optics SC Optics GA 412BC UT WOS:000167533300015 PM 18040324 ER PT J AU Baur, JW Durstock, MF Taylor, BE Spry, RJ Reulbach, S Chiang, LY AF Baur, JW Durstock, MF Taylor, BE Spry, RJ Reulbach, S Chiang, LY TI Photovoltaic interface modification via electrostatic self-assembly SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 16th International Conference on Science and Technology of Synthetic Metals (ICSM 2000) CY JUL 15-21, 2000 CL GASTEIN, AUSTRIA DE photovoltaics; solar cells; self-assembly; charge transfer; poly(p-phenylene vinylene); C-60 ID CONJUGATED POLYMERS; HETEROJUNCTIONS; LAYERS; DIODES; CELLS AB The device efficiency of PPV-C-60 based photovoltaic devices has been substantially increased by increasing the interfacial area between the electron donor and acceptor layers. Electrostatic Self-Assembly (ESA) provides a means to deposit thin films of electroactive materials with a very controlled thickness and has shown usefulness in modifying physical and electrical interfaces. in this study, we attempt to control the effective interfacial area by modifying the interface between the PPV electron donor and C-60-based electron acceptor with molecularly blended ESA bilayers of PPV and derivatized C-60 If is observed that with only 2 bilayers of (PPV/C-60(-)) a 3-fold increase in device efficiency is obtained. Thus, ESA films offer promise for the nanoscaled modification of interfaces in organic-based photocells. C1 USAF, Res Lab, Polymer Branch, MLBP, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Nonmet Mat Div, Dayton, OH 45469 USA. Natl Taiwan Univ, Ctr Condensed Matter Sci, Taipei 10764, Taiwan. RP Baur, JW (reprint author), USAF, Res Lab, Polymer Branch, MLBP, 2941 P St,Bldg 654, Wright Patterson AFB, OH 45433 USA. NR 10 TC 23 Z9 24 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAR 15 PY 2001 VL 121 IS 1-3 SI SI BP 1547 EP 1548 DI 10.1016/S0379-6779(00)01231-5 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 434TD UT WOS:000168831200211 ER PT J AU Steinhubl, SR Ellis, SG Wolski, K Lincoff, AM Topol, EJ AF Steinhubl, SR Ellis, SG Wolski, K Lincoff, AM Topol, EJ CA EPISTENT Investigators TI Ticlopidine pretreatment before coronary stenting is associated with sustained decrease in adverse cardiac events - Data from the Evaluation of Platelet IIb/IIIa Inhibitor for Stenting (EPISTENT) trial SO CIRCULATION LA English DT Article DE stents; restenosis; platelets ID EXPERIMENTAL ARTERIAL THROMBOGENESIS; ANTIPLATELET THERAPY; COMBINED ASPIRIN; ANGIOPLASTY; IMPLANTATION; RESTENOSIS; ANTICOAGULATION; PROLIFERATION; DIPYRIDAMOLE; CLOPIDOGREL AB Background-Platelet inhibition at the time of a percutaneous coronary intervention has consistently been shown to decrease the risk of thrombotic adverse events but not restenosis. The role of enhanced antiplatelet protection through pretreatment with the platelet ADP-receptor antagonist ticlopidine in preventing both the early and late complications of coronary stenting has not previously been explored. Methods and Results-In the Evaluation of Platelet Ilb/IIIa Inhibitor for Stenting (EPISTENT) trial, approximate to 1600 patients were randomized to stenting with either placebo or abciximab in addition to aspirin and heparin. All stented patients also received ticlopidine after the procedure, but 58% of these patients were given ticlopidine before stenting at the discretion of the investigating physician. Among patients randomized to placebo, ticlopidine pretreatment was associated with a significant decrease in the incidence of the composite end point of death, myocardial infarction, or target Vessel revascularization (TVR) at 1 year (adjusted hazard ratio, 0.73; 95% CI, 0.54 to 0.98; P=0.036). Ticlopidine pretreatment did not significantly influence the risk of death or myocardial infarction in patients randomized to abciximab. Controlling for patient characteristics and for the propensity of being on ticlopidine, Cox proportional hazards regression identified ticlopidine pretreatment as an independent predictor of the need for TVR at 1 year (hazard ratio, 0.62; 95% CI, 0.43 to 0.89; P=0.010) in both placebo-treated and abciximab-treated patients. Conclusions-In the EPISTENT trial, among patients randomized to stenting, starting ticlopidine before the percutaneous coronary intervention was associated with a significant decrease in the incidence of the 12-month composite end point for patients not receiving abciximab and the need for TVR among all patients. C1 Wilford Hall USAF Med Ctr, Dept Cardiol, Lackland AFB, TX 78236 USA. Cleveland Clin Fdn, Dept Cardiol, Cleveland, OH 44195 USA. Cleveland Clin Fdn, Joseph J Jacobs Ctr Thrombosis & Vasc Biol, Cleveland, OH 44195 USA. Cleveland Clin Fdn, Dept Biostat & Epidemiol, Cleveland, OH 44195 USA. RP Steinhubl, SR (reprint author), Wilford Hall USAF Med Ctr, Dept Cardiol, 2200 Bergquist Dr, Lackland AFB, TX 78236 USA. OI Topol, Eric/0000-0002-1478-4729 NR 31 TC 91 Z9 94 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD MAR 13 PY 2001 VL 103 IS 10 BP 1403 EP 1409 PG 7 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 413XJ UT WOS:000167636600018 PM 11245644 ER PT J AU Lork, E Mews, R Viets, D Watson, PG Borrmann, T Vij, A Boatz, JA Christe, KO AF Lork, E Mews, R Viets, D Watson, PG Borrmann, T Vij, A Boatz, JA Christe, KO TI Structure of the SO2F- anion, a problem case SO INORGANIC CHEMISTRY LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; GAUSSIAN-BASIS SETS; WAVE-FUNCTIONS; SPECTRA AB Recently, room-temperature crystal structures of SO2F- in its K+ and Rb+ salts were published in Z. Anorg. Allg. Chem. 1999, 625, 385 and claimed to represent the first reliable geometries for SO2F-. However, their almost identical S-O and S-F bond lengths and O-S-O and O-S-F bond angles are in sharp contrast to the results from theoretical calculations. To clarify this discrepancy, the new [(CH3)(2)N](3)SO+ and the known [N(CH3)(4)(+)], [(CH3)(2)N](3)S+, and K+ salts of SO2F- were prepared and their crystal structures studied at low temperatures. Furthermore, the results from previous RHF and MP2 calculations were confirmed at the RHF, B3LYP, and CCSD(T) levels of theory using different basis sets. It is shown that all the SO2F- salts studied so far exhibit varying degrees of oxygen/fluorine and, in some cases, oxygen-site disorders, with [(CH3)(2)N](3)SO+SO2F- at 113 K showing the least disorder with r(S-F) - r(S-O) = 17 pm and angle (O-S-O) angle (F-S-O) = 6 degrees. Refinement of the disorder occupancy factors and extrapolation of the observed bond distances for zero disorder resulted in a geometry very close to that predicted by theory. The correctness of the theoretical predictions for SO2F- is further supported by the good agreement between the calculated and the experimentally observed vibrational frequencies and their comparison with those of isoelectronic ClO2F. A normal coordinate analysis of SO2F- confirms the weakness of the S-F bond with a stretching force constant of only 1.63 mdyn/Angstrom and shows that there is no highly characteristic S-F stretching mode. The S-F stretch strongly couples with the SO2 deformation modes and is concentrated in the two lowest a' frequencies. C1 Univ Bremen, Dept Chem, D-28334 Bremen, Germany. USAF, Res Lab, Edwards AFB, CA 93524 USA. Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. RP Mews, R (reprint author), Univ Bremen, Dept Chem, Leobener Str NW2,POB 330440, D-28334 Bremen, Germany. RI Vij, Ashwani/A-2836-2012; Christe, Karl/O-4885-2014 OI Vij, Ashwani/0000-0003-1144-4080; Christe, Karl/0000-0003-0661-5519 NR 41 TC 13 Z9 13 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAR 12 PY 2001 VL 40 IS 6 BP 1303 EP 1311 DI 10.1021/ic000616p PG 9 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 409PT UT WOS:000167392600032 PM 11300833 ER PT J AU Adair, ER Mylacraine, KS Cobb, BL AF Adair, ER Mylacraine, KS Cobb, BL TI Human exposure to strong microwave fields (2450 MHz) does not increase core temperature SO FASEB JOURNAL LA English DT Meeting Abstract C1 USAF, Res Lab, HEDR, Brooks AFB, TX 78235 USA. Veridian Inc, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 8 PY 2001 VL 15 IS 5 BP A1109 EP A1109 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 410TA UT WOS:000167454202284 ER PT J AU Midey, AJ Williams, S Viggiano, AA AF Midey, AJ Williams, S Viggiano, AA TI Reactions of NO+ with isomeric butenes from 225 to 500 K SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ION FLOW TUBE; RATE CONSTANTS; TRAJECTORY CALCULATIONS; STATE; 1-BUTENE; ENERGY; CATIONS; ALKANES; O-2(+); H3O+ AB The rate constants and branching fractions have been measured for the reaction of NO+ with the four butene isomers of C4H8 from 225 to 500 K in a variable temperature-selected ion flow tube. The cis- and trans-2-butene isomers react at the collision rate via charge transfer over the entire temperature range. Isobutene also reacts at the collision rate at all temperatures, primarily through charge transfer; however, an association channel also competes effectively at the lowest temperatures studied because the charge transfer reaction is only 0.02 eV exothermic. The reaction of NO+ with 1-butene is much slower than observed for the other butenes and has a negative temperature dependence. The negative temperature dependence is consistent with the predominant product channel being association. Other products are also observed with 1-butene, including C4H7+ from hydride transfer, C4H8+ from charge transfer at higher temperatures, and several other products involving significant rearrangement and chemical bond formation. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Viggiano, AA (reprint author), USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. NR 42 TC 8 Z9 8 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 MAR 8 PY 2001 VL 105 IS 9 BP 1574 EP 1578 DI 10.1021/jp0019005 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 407JN UT WOS:000167268600021 ER PT J AU Boghosian, BM Yepez, J Coveney, PV Wager, A AF Boghosian, BM Yepez, J Coveney, PV Wager, A TI Entropic lattice Boltzmann methods SO PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE computational fluid dynamics; thermodynamics; hydrodynamics; entropy; numerical stability; lattice Boltzmann equation ID NAVIER-STOKES EQUATION; GAS MODEL; FLUID-DYNAMICS; H-THEOREM; SIMULATIONS; SYSTEMS AB We present a general methodology for constructing lattice Boltzmann models of hydrodynamics with certain desired features of statistical physics and kinetic theory. We show how a methodology of linear programming theory, known as Fourier-Motzkin elimination, provides an important tool for visualizing the state-space of lattice Boltzmann algorithms that conserve a given set of moments of the distribution function. We show how such models can be endowed with a Lyapunov functional, analogous to Boltzmann's H, resulting in unconditional numerical stability. Using the Chapman-Enskog analysis and numerical simulation, we demonstrate that such entropically stabilized lattice Boltzmann algorithms, while fully explicit and perfectly conservative, may achieve remarkably low values for transport coefficients, such as viscosity. Indeed, the lowest such attainable values are limited only by considerations of accuracy, rather than stability. The method thus holds promise for high-Reynolds-number simulations of the Navier-Stokes equations. C1 Tufts Univ, Dept Math, Medford, MA 02155 USA. USAF, Bedford, MA 01731 USA. Univ London, Ctr Computat Sci, London E1 4NS, England. RP Boghosian, BM (reprint author), Tufts Univ, Dept Math, Bromfield Pearson Hall, Medford, MA 02155 USA. EM bruce.boghosian@tufts.edu; yepez@plh.af.mil; p.v.coveney@qmw.ac.uk; awagner@mit.edu NR 34 TC 92 Z9 93 U1 1 U2 11 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-5021 EI 1471-2946 J9 P ROY SOC A-MATH PHY JI Proc. R. Soc. A-Math. Phys. Eng. Sci. PD MAR 8 PY 2001 VL 457 IS 2007 BP 717 EP 766 PG 50 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 410GK UT WOS:000167432100011 ER PT J AU Xie, W Gao, ZM Liu, KL Pan, WP Vaia, R Hunter, D Singh, A AF Xie, W Gao, ZM Liu, KL Pan, WP Vaia, R Hunter, D Singh, A TI Thermal characterization of organically modified montmorillonite SO THERMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 27th North-American-Thermal-Analysis-Society Conference CY SEP 20-22, 1999 CL SAVANNAH, GEORGIA SP N Amer Thermal Anal Soc DE organically modified layered silicate; thermogravimetric analysis; nanocomposites; thermal stability AB Polymer/organically modified layered silicate (PLS) nanocomposites are a new class of filled polymers with ultrafine phase dimensions, They offer an outstanding combination of stiffness, strength and weight that is difficult to attain separately from the individual components. Additionally, the nanoscopic phase distribution as well as synergism between polymer and the layered silicate result in additional properties, such as flame retardency, enhanced barrier properties and ablation resistance, which are not observed in either component. These nanocomposites are synthesized by blending the organically modified layered silicate (OLS) into the polymer melt. Thus, understanding the relationship between the molecular structure and the thermal stability (decomposition temperature. rate, and the degradation products) of the organic modification of the layered silicate is critical, During this study, modern thermal analysis techniques combined with infrared spectroscopy and mass spectrometry (TGA-FTIR-MS) were used to obtain information on the thermal stability and degradation products. The effect of chemical variation (alkyl chain length, number of alkyls, and unsaturation) of organic modifiers on the thermal stability of the organically exchanged montmorillonite are discussed. A range of interesting results is observed, however, not all are currently understandable. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Western Kentucky Univ, Dept Chem, Thermal Anal Lab, Ctr Mat Characterizat, Bowling Green, KY 42101 USA. AFRL, MLBP, Wright Patterson AFB, OH 45433 USA. So Clay Prod Inc, Gonzales, TX 78629 USA. Triton Syst Inc, Chelmsford, MA 01824 USA. RP Xie, W (reprint author), Western Kentucky Univ, Dept Chem, Thermal Anal Lab, Ctr Mat Characterizat, Bowling Green, KY 42101 USA. NR 20 TC 212 Z9 227 U1 1 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD MAR 8 PY 2001 VL 367 BP 339 EP 350 DI 10.1016/S0040-6031(00)00690-0 PG 12 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 414FU UT WOS:000167656100041 ER PT J AU Ahuja, SK Gonzalez, E Dhanda, R Mumnudi, S Bamshad, M Telles, V Anderson, S Walter, EA Stephan, KT Ahuja, SS Dolan, MJ AF Ahuja, SK Gonzalez, E Dhanda, R Mumnudi, S Bamshad, M Telles, V Anderson, S Walter, EA Stephan, KT Ahuja, SS Dolan, MJ TI A mutant MCP-1 haplotype alters risks of HIV-1 infection and HIV-associated dementia SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Texas, Hlth Sci Ctr, Dept Med, San Antonio, TX 78229 USA. Pudue Pharma LP, BCDM, Stamford, CT USA. Univ Utah, Dept Pediat, Eccles Inst Human Genet, Salt Lake City, UT USA. Wilford Hall USAF Med Ctr, Henry M Jackson Fdn, Lackland AFB, TX 78236 USA. Wilford Hall USAF Med Ctr, Infect Dis Serv, Lackland AFB, TX 78236 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 7 PY 2001 VL 15 IS 4 BP A359 EP A359 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 410KA UT WOS:000167438102057 ER PT J AU Pechenick, A Chen, IW AF Pechenick, A Chen, IW TI Advanced silicon nih ide ceramics SO ADVANCED MATERIALS & PROCESSES LA English DT Article C1 USAF, Res Lab, Off Sci Res, Arlington, VA USA. Univ Penn, Philadelphia, PA 19104 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 0882-7958 J9 ADV MATER PROCESS JI Adv. Mater. Process. PD MAR PY 2001 VL 159 IS 3 BP 37 EP 37 PG 1 WC Materials Science, Multidisciplinary SC Materials Science GA 408AJ UT WOS:000167304100005 ER PT J AU Manke, GC Henshaw, TL Madden, TJ Herbelin, JM Rafferty, BD Hager, GD AF Manke, GC Henshaw, TL Madden, TJ Herbelin, JM Rafferty, BD Hager, GD TI Characterizing fluorine and chlorine atom flow rates using iodine atom spectrometry SO AIAA JOURNAL LA English DT Article ID 1.315 MU-M; ENERGY-TRANSFER; CHEMICAL-LASER; RATE CONSTANTS; NCL(A(1)DELTA); TRANSITION; I(2P1/2); I(2P3/2); 2P1/2); F2 AB The production of F and Cl atoms in an electrical discharge of F-2 or Cl-2 has been examined in a flow reactor. A tunable diode laser was used to probe the concentration and translational temperature of I atoms produced by F and Cl atom reactions with HI. Kinetic modeling codes were used to determine the discharge efficiencies from the titration plots and the observed trends fur atom concentration as a function of F-2 or Cl-2 and pressure. These calculations indicate that the de discharge used in these experiments is 100% efficient for F-2 flow rates less than or equal to0.5 mmol s(-1) and reactor pressure less than or equal to 20 torr. The highest F-2-free F atom Row rate that we can generate is 1.0 mmol s(-1). Preliminary data for the Cl-2 discharge indicate that this is a much less efficient source of Cl atoms with yields of less than 50%. C1 USAF, Res Lab, High Power Gas Lasers Branch, Kirtland AFB, NM 87117 USA. RP Manke, GC (reprint author), USAF, Res Lab, High Power Gas Lasers Branch, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 36 TC 18 Z9 19 U1 0 U2 1 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 MAR PY 2001 VL 39 IS 3 BP 447 EP 454 DI 10.2514/2.1325 PG 8 WC Engineering, Aerospace SC Engineering GA 409JQ UT WOS:000167380900011 ER PT J AU Ahrendt, DM AF Ahrendt, DM TI Ergogenic aids: Counseling the athlete SO AMERICAN FAMILY PHYSICIAN LA English DT Article ID CREATINE SUPPLEMENTATION; ORAL ANDROSTENEDIONE; PROTEIN-REQUIREMENTS; CYCLING PERFORMANCE; PROLONGED EXERCISE; SERUM TESTOSTERONE; BODY-COMPOSITION; MUSCLE GLYCOGEN; GLYCEMIC INDEX; YOUNG MEN AB Numerous ergogenic aids that claim to enhance sports performance are used by amateur and professional athletes. Approximately 50 percent of the general population have reported taking some form of dietary supplements, while 76 to 100 percent of athletes in some sports are reported to use them. Physicians can evaluate these products by examining four factors (method of action, available research, adverse effects, legality) that will help them counsel patients. Common ergogenic aids include anabolic steroids, which increase muscle mass. These illegal supplements are associated with a number of serious adverse effects, some irreversible. Creatine modestly improves athletic performance and appears to be relatively safe. Dehydroepiandrosterone and androstenedione do not improve athletic performance but apparently have similar adverse effects as testosterone and are also banned by some sports organizations. Caffeine has mild benefits and side effects and is banned above certain revels. Products that combine caffeine with other stimulants (e.g., ephedrine) have been linked to fatal events. Protein and carbohydrate supplementation provides modest benefits with no major adverse effects. C1 San Antonio Mil Pediat Ctr, Div Adolescent Med, San Antonio, TX USA. RP Ahrendt, DM (reprint author), Dept Pediat, 2200 Berquist Dr,Ste 1, Lackland AFB, TX 78236 USA. NR 40 TC 33 Z9 35 U1 0 U2 8 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 MAR 1 PY 2001 VL 63 IS 5 BP 913 EP 922 PG 10 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 409CX UT WOS:000167367900010 PM 11261867 ER PT J AU Pluntze, SC AF Pluntze, SC TI Answer to Question #71. Birds and bombers - Why the V-formation? SO AMERICAN JOURNAL OF PHYSICS LA English DT Letter C1 USAF Acad, Dept Aeronaut Engn, Colorado Springs, CO 80840 USA. RP Pluntze, SC (reprint author), USAF Acad, Dept Aeronaut Engn, Colorado Springs, CO 80840 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 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD MAR PY 2001 VL 69 IS 3 BP 247 EP 247 DI 10.1119/1.1343860 PG 1 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 404RD UT WOS:000167113700006 ER PT J AU Ladeinde, F Cai, XD Visbal, MR Gaitonde, DV AF Ladeinde, F Cai, XD Visbal, MR Gaitonde, DV TI Turbulence spectra characteristics of high order schemes for direct and large eddy simulation SO APPLIED NUMERICAL MATHEMATICS LA English DT Article DE turbulence spectra; essentially nonoscillatory schemes; compact schemes; high-order schemes; filters; direct numerical simulation; large eddy simulation ID ESSENTIALLY NONOSCILLATORY SCHEMES; SHOCK-CAPTURING SCHEMES; EFFICIENT IMPLEMENTATION; ENO SCHEMES AB The comparative resolution of the high wavenumber portion of compressible turbulence energy spectrum by some high order numerical schemes is presented in this paper, included in this are the essentially nonoscillatory (ENO) schemes, the weighted essentially nonoscillatory schemes (WENO), and the compact differencing schemes. The governing equations are the Navier-Stokes equations and the objective is to identify the numerical scheme that best represents the physics of compressible turbulence. Mach numbers MI values of 0.1, 0.5 and 0.7 are studied. The compact differencing schemes need filters for numerical stability. It is found in this work that a parameter in the filter scheme provides some flexibility for controlling the physical turbulence energy transfer rate at high wavenumbers, vis-a-vis the numerical dissipation at those scales. Although the ENO schemes do not require filters for numerical stability, the present study shows that the addition of filters improves the energy transfer process at high wavenumbers. Without filtering, with relatively coarse grids, numerical turbulence caused by stencil adaptation persists. This limits the useful wavenumber resolution range of the ENO schemes. The WENO schemes do not require the stabilizing filters but the results tend to he slightly more dissipative. Finally, at low Mach numbers, the current compact differencing and filter scheme formulation gives better results but as the Mach number increases the relative suitability of the ENO method increases. (C) 2001 IMACS. Published by Elsevier Science B.V. All rights reserved. C1 Aerosp Res Corp, LI, Long Isl, NY 11790 USA. USAF, Res Lab, Air Vehicles Directorate, Wright Patterson AFB, OH 45433 USA. RP Ladeinde, F (reprint author), Aerosp Res Corp, LI, POB 1527, Long Isl, NY 11790 USA. NR 23 TC 15 Z9 15 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9274 J9 APPL NUMER MATH JI Appl. Numer. Math. PD MAR PY 2001 VL 36 IS 4 BP 447 EP 474 DI 10.1016/S0168-9274(00)00019-2 PG 28 WC Mathematics, Applied SC Mathematics GA 404FM UT WOS:000167086800005 ER PT J AU Neuhauser, TS Derringer, GA Thompson, LDR Fanburg-Smith, JC Aguilera, NSI Andriko, J Chu, WS Abbondanzo, SL AF Neuhauser, TS Derringer, GA Thompson, LDR Fanburg-Smith, JC Aguilera, NSI Andriko, J Chu, WS Abbondanzo, SL TI Splenic inflammatory myofibroblastic tumor (inflammatory pseudotumor) - A clinicopathologic and immunophenotypic study of 12 cases SO ARCHIVES OF PATHOLOGY & LABORATORY MEDICINE LA English DT Article ID EPSTEIN-BARR-VIRUS; PLASMA-CELL GRANULOMA; XIII F-XIIIA; IMMUNOHISTOCHEMICAL DEMONSTRATION; RETICULUM CELLS; SPLEEN; INTERLEUKIN-1; HAMARTOMA; PROLIFERATION; FIBROSARCOMA AB Context.-Inflammatory pseudotumor is an uncommon and enigmatic lesion. The spindle cells found in this tumor have features of myofibroblasts. Because of the indefinite relationship of these lesions with inflammatory fibrosarcoma and their indefinite biologic behavior, inflammatory pseudotumor is currently classified as inflammatory myo fibroblastic tumor (IMT). To date, only case reports or small series have been published on these tumors, which are primary in the spleen. Design.-In this study, we describe the clinical, morphologic, and immunophenotypic findings of 12 cases of splenic IMT and examine their relationship to Epstein-Barr virus (EBV). Results.-The patients included 8 women and 3 men, ranging from 19 to 77 years of age (mean, 53 years; median, 60 years). Demographic data were unavailable for 1 patient. Patients generally presented with abdominal pain (n = 5) and fever (n = 4). Associated lesions included renal cell carcinoma (n = 2), colonic adenocarcinoma (n = 1), and cholecystitis (n = 1). All tumors were composed of a bland spindle cell proliferation in association with a variable mixed inflammatory component. There were 2 growth patterns, namely, a cellular spindle cell pattern and a hypocellular fibrous pattern. An immunohistochemical panel confirmed the myofibroblastic nature of the spindle cells. The spindle cells of 2 cases were immunoreactive for EBV latent membrane protein 1, whereas 6 of 10 cases were positive for EBV-encoded RNA using in situ hybridization. Follow-up was available for 8 patients; 6 were alive with no evidence df recurrence and 2 were dead of other causes. Conclusion.-Splenic IMTs are uncommon lesions that can be distinguished from other conditions using a combination of clinical, histologic, and immunophenotypic findings. Epstein-Barr virus may play a role in the pathogenesis of splenic IMT, and there may be an association of splenic IMT with concomitant disease or malignancy. Most splenic IMTs have an excellent long-term prognosis. C1 Armed Forces Inst Pathol, Dept Hematopathol, Washington, DC 20306 USA. Armed Forces Inst Pathol, Dept Endocrine & Otorhinolaryng Head & Neck Patho, Washington, DC 20306 USA. Armed Forces Inst Pathol, Dept Soft Tissue Pathol, Washington, DC 20306 USA. RP Neuhauser, TS (reprint author), Wilford Hall USAF Med Ctr, Dept Pathol, MTLP, 2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. RI Thompson, Lester/J-8404-2016 OI Thompson, Lester/0000-0003-3714-1432 NR 51 TC 67 Z9 68 U1 0 U2 1 PU COLLEGE AMER PATHOLOGISTS PI NORTHFIELD PA C/O KIMBERLY GACKI, 325 WAUKEGAN RD, NORTHFIELD, IL 60093-2750 USA SN 0003-9985 J9 ARCH PATHOL LAB MED JI Arch. Pathol. Lab. Med. PD MAR PY 2001 VL 125 IS 3 BP 379 EP 385 PG 7 WC Medical Laboratory Technology; Medicine, Research & Experimental; Pathology SC Medical Laboratory Technology; Research & Experimental Medicine; Pathology GA 409UX UT WOS:000167405000015 PM 11231487 ER PT J AU Colette, D AF Colette, D TI Economic strategy and national security: A next generation approach. SO ARMED FORCES & SOCIETY LA English DT Book Review C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Colette, D (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU TRANSACTION PERIOD CONSORTIUM PI PISCATAWAY PA DEPT 4010, RUTGERS UNIV, 35 BERRUE CIRCLE, PISCATAWAY, NJ 08854-8042 USA SN 0095-327X J9 ARMED FORCES SOC JI Armed Forces Soc. PD SPR PY 2001 VL 27 IS 3 BP 494 EP 497 DI 10.1177/0095327X0102700311 PG 4 WC Political Science; Sociology SC Government & Law; Sociology GA 445VC UT WOS:000169478400014 ER PT J AU Cohen, D Otakeno, S Previc, FH Ercoline, WR AF Cohen, D Otakeno, S Previc, FH Ercoline, WR TI Effect of "inside-out" and "outside-in attitude displays on off-axis tracking in pilots and nonpilots SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE spatial disorientation; situation awareness; attitude displays; helmet-mounted displays; tracking; control-display compatibility ID AVIATION SPATIAL ORIENTATION; HEAD POSITION; PERFORMANCE; SYMBOLOGY; ILLUSION AB Background: Pilots employing helmet-mounted displays spend sustained periods of time locking off-axis, necessitating the inclusion of attitude symbology on the helmet to maintain spatial awareness. We examined how fundamentally different altitude references, a moving-horizon ("inside-out") or a moving-aircraft ("outside-in"), affected pilot and nonpilot attitude control when looking on- or off-axis. Both a rear-view and a side-view outside-in perspective were depicted to investigate the effect of control-display compatibility. Methods: Subjects performed a compensatory pitch-roil tracking task either looking on-axis or 90 degrees off-axis using three symbologies: 1) a compressed pitch ladder with horizon line; 2) a 3-D aircraft representation Viewed from the rear; and 3) a 3-D aircraft representation viewed from the side. Tracking error in roll and pitch, control bias, and subjective ratings were collected and analyzed. Results: There was no significant difference in the tracking performance of U.S. Air Force pilots in pitch and roll using the inside-out or outside-in rear-view formats on- and off-axis, although they preferred the inside-out format. Nonpilots tracked significantly better using the outside-in rear-view format, which they also preferred. Both groups tracked poorly using the outside-in side-view format and control-display compatibility had no important effect. Conclusions: Pilots are equally adept using outside-in and inside-out displays. Given that an outside-in display may better reflect a person's inherent frame of reference for orientation las evidenced by the nonpilots' superior performance with ill, the results seem to indicate that pilots, through experience, have adapted to an inside-out frame of reference. C1 USAF, Res Lab, Biodynam & Protect Div, Brooks AFB, TX USA. Veridian, Brooks AFB, TX USA. RP Cohen, D (reprint author), 1582C Eglin Way, Bolling AFB, DC 20332 USA. NR 23 TC 7 Z9 7 U1 0 U2 2 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2001 VL 72 IS 3 BP 170 EP 176 PG 7 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 406LF UT WOS:000167217100003 PM 11277281 ER PT J AU Hilton, AD Hursh, TA AF Hilton, AD Hursh, TA TI Type 2 diabetes in an aviator, protein diet vs. traditional diet: Case report SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE aviator; diabetes mellitis; protein diet; insulin resistance AB An experienced helicopter pilot with hypertension, hyper-triglyceridemia, elevated cholesterol, obesity, and diabetes is treated with a high-protein, low-carbohydrate diet. In 3 months, he loses 35 lbs, is normotensive without medication, cholesterol and triglycerides show significant reduction, fasting blood glucose and 2-h post glucose load are normal. At follow-up 1 yr later he has maintained hemoglobin A1C in the low 5 range. The protein diet is discussed and compared with the traditional dietary approach for type 2 diabetes. C1 28th Aeromed Dent Squadron, SGGF, Ellsworth AFB, SD 57706 USA. RP Hilton, AD (reprint author), 28th Aeromed Dent Squadron, SGGF, 2900 Doolittle Dr, Ellsworth AFB, SD 57706 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2001 VL 72 IS 3 BP 219 EP 220 PG 2 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 406LF UT WOS:000167217100010 PM 11277288 ER PT J AU Carretta, TR AF Carretta, TR TI USAF pilot selection and training - Response SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Letter C1 USAF, Res Lab, Crew Syst Dev Branch, Wright Patterson AFB, OH 45433 USA. RP Carretta, TR (reprint author), USAF, Res Lab, Crew Syst Dev Branch, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2001 VL 72 IS 3 BP 228 EP 228 PG 1 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 406LF UT WOS:000167217100013 ER PT J AU Johnson, LM AF Johnson, LM TI USAF pilot selection and training SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Letter C1 USAF Acad, Off Command Surgeon, Colorado Springs, CO 80840 USA. RP Johnson, LM (reprint author), USAF Acad, Off Command Surgeon, Colorado Springs, CO 80840 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD MAR PY 2001 VL 72 IS 3 BP 228 EP 228 PG 1 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 406LF UT WOS:000167217100012 PM 11277290 ER PT J AU Hazel, J Fuchigami, N Gorbunov, V Schmitz, H Stone, M Tsukruk, VV AF Hazel, J Fuchigami, N Gorbunov, V Schmitz, H Stone, M Tsukruk, VV TI Ultramicrostructure and microthermomechanics of biological IR detectors: Materials properties from a biomimetic perspective SO BIOMACROMOLECULES LA English DT Article ID SCANNING PROBE MICROSCOPY; MICROMECHANICAL PROPERTIES; POLYMERIC MATERIALS; INFRARED RECEPTOR; BUPRESTIDAE; COLEOPTERA; BEETLE; FILMS AB Microstructural organization of the biological infrared (IR) receptors was studied to elucidate their materials properties useful for prospective biomimetic design of artificial IR sensors from organic/polymeric materials. The IR receptors in Melanophila acuminata beetles were studied with ultrahigh-resolution scanning probe microscopy (SPM) in a range of temperatures. By application of micromechanical mapping and thermal stage, we made attempts to reveal the micromechanical and thermomechanical properties of the cuticular apparatus of the LR sensillum. The main component of the cuticular apparatus is an internal endocuticular sphere with a diameter of about 15-20 mum. Highly ordered multilayered organization of the lamellated peripheral mantle of the sphere was confirmed and characterized. We observed that the interlayer spacing of this microstructure varied along the circumference and decreased to 300 nm in the vertex of the sphere. We demonstrated that the microlayered structure is composed of nanolayers with very different micromechanical properties and thermal behaviors. Thermal expansion of the outer mantle was observed, and the local thermal expansion coefficient under given preparation conditions was estimated to be below 1.5 x 10(-4) grad(-1). C1 Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Western Michigan Univ, Mat Sci & Engn Program, Kalamazoo, MI 49008 USA. Univ Bonn, Inst Zool, D-53115 Bonn, Germany. USAF, Res Lab, MLPJ, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Tsukruk, VV (reprint author), Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. NR 23 TC 16 Z9 16 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1525-7797 J9 BIOMACROMOLECULES JI Biomacromolecules PD SPR PY 2001 VL 2 IS 1 BP 304 EP 312 DI 10.1021/bm005648i PG 9 WC Biochemistry & Molecular Biology; Chemistry, Organic; Polymer Science SC Biochemistry & Molecular Biology; Chemistry; Polymer Science GA 433JG UT WOS:000168755800041 PM 11749187 ER PT J AU Walters, MK AF Walters, MK TI A simple example of Galilean invariance in the omega equation SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article AB This paper is pedagogically motivated to qualitatively demonstrate basic concepts related to Galilean invariance and partial cancellation in the individual forcing terms in the traditional form of the omega equation. The analysis provides examples of the vertical distribution of the primary quasigeostrophic (QG) forcing, showing how the individual forcing terms vary in different coordinate systems while their sum remains constant. The QG forcing is described analytically using an unstable Eady wave solution, which allows depictions of QG forcing similar to those in basic atmospheric dynamics texts. The perturbation streamfunction, temperature, and vertical velocity are seen to be invariant under change of horizontal coordinate system, while the individual magnitudes of the QG vertical motion forcing are not. The total QG forcing remains invariant in all cases and is equal to the QG forcing found from the divergence of the Q vector. The figures provided can supplement those used for traditional study and may be useful to provoke classroom discussion of related QG concepts. C1 USAF, Inst Technol, Dept Engn Phys, Wright Patterson AFB, OH 45433 USA. RP Walters, MK (reprint author), USAF, Inst Technol, Dept Engn Phys, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 10 TC 4 Z9 4 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAR PY 2001 VL 82 IS 3 BP 463 EP 472 DI 10.1175/1520-0477(2001)082<0463:ASEOGI>2.3.CO;2 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 406RG UT WOS:000167228500004 ER PT J AU Chen, JK Beraun, JE Jih, CJ AF Chen, JK Beraun, JE Jih, CJ TI A corrective smoothed particle method for transient elastoplastic dynamics SO COMPUTATIONAL MECHANICS LA English DT Article ID FREE GALERKIN METHOD; COMPUTATIONAL MECHANICS; HYDRODYNAMICS; SPH; COMPLETENESS AB An incremental approach is presented to model transient, elastoplastic dynamic problems using the corrective smoothed particle method. It uses the corrective first- and second-derivative approximations to solve the nonlinear momentum equations, which is described in terms of displacement increments entirely. This algorithm not only satisfies the nodal completeness condition but also exhibits no integrablity problem. Several 2D examples, including forced vibration, stress wave propagation, and rigid wall impact, are investigated to demonstrate the numerical stability and accuracy of the proposed method. C1 USAF, Res Lab, Laser Effects Res Branch, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Ford Res Lab, Vehicle Elect Syst Dept, Dearborn, MI 48121 USA. RP Chen, JK (reprint author), USAF, Res Lab, Laser Effects Res Branch, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 33 TC 9 Z9 10 U1 0 U2 4 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 MAR PY 2001 VL 27 IS 3 BP 177 EP 187 DI 10.1007/s004660100236 PG 11 WC Mathematics, Interdisciplinary Applications; Mechanics SC Mathematics; Mechanics GA 421LK UT WOS:000168065700001 ER PT J AU Cassady, CR Murdock, WP Pohl, EA AF Cassady, CR Murdock, WP Pohl, EA TI Selective maintenance for support equipment involving multiple maintenance actions SO EUROPEAN JOURNAL OF OPERATIONAL RESEARCH LA English DT Article DE maintenance; minimal repair; preventive maintenance; reliability; optimization ID MODELS; SYSTEMS AB Selective maintenance is the process of identifying a subset among sets of desirable maintenance actions. Previous works use mathematical programming models for making selective maintenance decisions for production equipment and military vehicles, which perform sequences of missions and are repaired only between missions. In this paper, extensions of these models are proposed. First, system component life is assumed to follow Weibull distributions. Second, the decision-maker is given multiple maintenance options: minimal repair on failed components, replacement of failed components, and replacement of functioning components (preventive maintenance). (C) 2001 Published by Elsevier Science B.V. C1 USAF, Inst Technol, Dept Operat Sci, Wright Patterson AFB, OH 45433 USA. Univ Arkansas, Dept Ind Engn, Fayetteville, AR 72701 USA. USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Murdock, WP (reprint author), USAF, Inst Technol, Dept Operat Sci, Wright Patterson AFB, OH 45433 USA. NR 6 TC 42 Z9 50 U1 2 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-2217 J9 EUR J OPER RES JI Eur. J. Oper. Res. PD MAR 1 PY 2001 VL 129 IS 2 BP 252 EP 258 PG 7 WC Management; Operations Research & Management Science SC Business & Economics; Operations Research & Management Science GA 387CV UT WOS:000166103300004 ER PT J AU Bolia, RS D'Angelo, WR Mishler, PJ Morris, LJ AF Bolia, RS D'Angelo, WR Mishler, PJ Morris, LJ TI Effects of hearing protectors an auditory localization in azimuth and elevation SO HUMAN FACTORS LA English DT Article ID SOUND LOCALIZATION; SPECTRAL CUES; TOPOGRAPHY; ACUITY; SPACE; PLANE AB An experiment was conducted to determine the effects of two types of hearing protectors on auditory localization performance. Six listeners localized a 750-ms broadband noise from loudspeakers ranging in azimuth from -180 degrees to +180 degrees and in elevation from -75 degrees to +90 degrees. Independent variables included the type of hearing protector and the elevation of the source. Dependent measures included azimuth error, elevation error, and the percentage of trials resulting in a front-back confusion. Performance on each of the dependent measures was found to be mediated by one or more of the independent variables. Actual or potential applications include the generation of improved design guidelines fur hearing protectors and workplace alarms. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Univ Connecticut, Ctr Hlth, Farmington, CT USA. Dayton Vet Affairs Med Ctr, Dayton, OH USA. Wright Patterson AF Base Med Ctr, Wright Patterson AFB, OH USA. RP Bolia, RS (reprint author), USAF, Res Lab, AFRL HECP,2255 H St, Wright Patterson AFB, OH 45433 USA. NR 21 TC 11 Z9 11 U1 0 U2 1 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 SPR PY 2001 VL 43 IS 1 BP 122 EP 128 DI 10.1518/001872001775992499 PG 7 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 453KM UT WOS:000169915100010 PM 11474758 ER PT J AU Draper, MH Viirre, ES Furness, TA Gawron, VJ AF Draper, MH Viirre, ES Furness, TA Gawron, VJ TI Effects of image scale and system time delay on simulator sickness within head-coupled virtual environments SO HUMAN FACTORS LA English DT Article ID MOTION SICKNESS; HYPOTHESIS AB Novel patterns of visual-vestibular intersensory stimulation often result in symptoms of simulator sickness, raising health and safety concerns regarding virtual environment exposure. Two experiments investigated the effect of conflicting visual-vestibular cues on subjective reports of simulator sickness during and after a 30-min exposure to a head-coupled virtual interface. Virtual image scale factors (0.5, 1.0, 2.0 magnification, generated by varying geometric field of view angle) were investigated in Experiment 1, and additional system time delays (125, 250 ms) were investigated in Experiment 2. Simulator sickness metrics included spoken self-reports during exposure and simulator sickness questionnaires (pre-exposure. immediate postexposure, and 20 min postexposure). Head yaw angular position data were also recorded. Reports of simulator sickness symptoms were significantly greater in the minification (0.5) and magnification (2.0) image scale factor conditions than in the neutral condition (1.0). Simulator sickness did not vary with changes in time delay, however. Furthermore, a comparison across experiments suggests no appreciable increase in simulator sickness with increasing time delays above the nominal value (48 ms). Head angular position data exhibited certain systematic variations across conditions. Actual or potential applications of this research include virtual environment training, simulation, and entertainment systems. C1 USAF, Res Lab, HECP, Wright Patterson AFB, OH 45433 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Univ Washington, Seattle, WA 98195 USA. Veridian Engn, Buffalo, NY USA. RP Draper, MH (reprint author), USAF, Res Lab, HECP, 2255 H St, Wright Patterson AFB, OH 45433 USA. EM mark.draper@wpafb.af.mil NR 31 TC 64 Z9 64 U1 3 U2 11 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 0018-7208 J9 HUM FACTORS JI Hum. Factors PD SPR PY 2001 VL 43 IS 1 BP 129 EP 146 DI 10.1518/001872001775992552 PG 18 WC Behavioral Sciences; Engineering, Industrial; Ergonomics; Psychology, Applied; Psychology SC Behavioral Sciences; Engineering; Psychology GA 453KM UT WOS:000169915100011 PM 11474759 ER PT J AU Stytz, MR Banks, SB Johnson, TD Lewis, JM Rothermel, SA AF Stytz, MR Banks, SB Johnson, TD Lewis, JM Rothermel, SA TI The Virtual SpacePlane SO IEEE COMPUTER GRAPHICS AND APPLICATIONS LA English DT Article ID ENVIRONMENTS C1 USAF, Res Lab, Wright Patterson AFB, OH 45431 USA. RP Stytz, MR (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45431 USA. NR 17 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 90720-1314 USA SN 0272-1716 J9 IEEE COMPUT GRAPH JI IEEE Comput. Graph. Appl. PD MAR-APR PY 2001 VL 21 IS 2 BP 42 EP 52 DI 10.1109/38.909014 PG 11 WC Computer Science, Software Engineering SC Computer Science GA 404WR UT WOS:000167125500007 ER PT J AU Sun, G Soref, RA Khurgin, JB AF Sun, G Soref, RA Khurgin, JB TI Phonon-pumped SiGe-Si interminiband terahertz laser SO IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS LA English DT Article DE phonon engineering; semiconductor laser; SiGe; superlattice AB The first phononpumped semiconductor laser has been proposed and theoretically investigated. The active region is an unbiased boron-doped Si0.94Ge0.06/Si superlattice with Si0.97Ge0.03 buffer layers embedded in a surface-plasmon strip waveguide. Warm and cool heat sinks create a temperature gradient across the waveguide. A heat buffer layer adjacent to the cool sink reflects optical phonons and transmits acoustic phonons. Within the resonator, the difference in effective temperatures of optical and acoustic phonons provides hole pumping for the lasing transition between the heavy-hole 2 (HH2) and heavy-hole 1 (HH1) minibands. A gain of 280/cm at the 5 THz emission frequency is predicted for 6 x 10(17)/cm(3) doping at temperatures of 300 K and 77 K for optical and acoustic phonons, respectively. A range of operating conditions in phonon-pumped IV-IV, III-V, and II-VI materials appears feasible. C1 Univ Massachusetts, Dept Phys, Boston, MA 02125 USA. USAF, Res Lab, Sensors Directorate, Bedford, MA 01731 USA. Johns Hopkins Univ, Dept Elect & Comp Engn, Baltimore, MD 21218 USA. RP Sun, G (reprint author), Univ Massachusetts, Dept Phys, Boston, MA 02125 USA. RI khurgin, Jacob/A-3278-2010 NR 4 TC 3 Z9 3 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1077-260X J9 IEEE J SEL TOP QUANT JI IEEE J. Sel. Top. Quantum Electron. PD MAR-APR PY 2001 VL 7 IS 2 BP 376 EP 380 DI 10.1109/2944.954153 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 479YW UT WOS:000171432800038 ER PT J AU Fikioris, G Wu, TT AF Fikioris, G Wu, TT TI On the application of numerical methods to Hallen's equation SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE Galerkin's method; integral equation methods; wire antennas ID WIRE AB The so-failed Hallen integral equation for the current on a finite linear antenna center-driven by a delta-function generator takes two forms depending on the choice of kernel. The two kernels are usually referred to as the exact and the approximate or reduced kernel. With the approximate kernel, the integral equation has no solution, Nevertheless, the same numerical method is often applied to both forms of the integral equation. In this paper, the behavior of the numerical solutions thus obtained is investigated, and the similarities and differences between the two numerical solutions are discussed. The numerical method is Galerkin's method with pulse functions, We first apply this method to the two corresponding forms of the integral equation for the current on a linear antenna of infinite length. In this case, the method yields an infinite Toeplitz system of algebraic equations in which the width of the pulse basis functions enters as a parameter. The infinite system is solved exactly for nonzero pulse width; the exact solution is then developed asymptotically for the case where the pulse width is small. When the asymptotic expressions for the case of the infinite antenna are used as a guide for the behavior of the solutions of the finite antenna, the latter problem is greatly facilitated, For the approximate kernel, the main results of this paper carry over to a certain numerical method applied to the corresponding equation of the Pocklington type. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01730 USA. Harvard Univ, Gordon Mckay Lab, Cambridge, MA 02138 USA. RP Fikioris, G (reprint author), Natl Tech Univ Athens, Dept Elect & Comp Engn, Inst Commun & Comp Syst, Athens, Greece. NR 27 TC 51 Z9 51 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD MAR PY 2001 VL 49 IS 3 BP 383 EP 392 DI 10.1109/8.918612 PG 10 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 426PT UT WOS:000168358100009 ER PT J AU Weinstock, H Osofsky, M AF Weinstock, H Osofsky, M TI The 2000 Applied Superconductivity Conference - Pavilion Convention Center, Virginia Beach, VA, September 17-22, 2000 - Chairmen's Introduction to the ASC 2000 proceedings SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Editorial Material C1 USAF, Off Sci Res, Washington, DC 20330 USA. USN, Res Lab, Washington, DC USA. RP Weinstock, H (reprint author), USAF, Off Sci Res, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 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 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 29 EP 29 PN 1 PG 1 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400001 ER PT J AU Fleet, E Gilbertson, A Chatraphorn, S Tralshawala, N Weinstock, H Wellstood, FC AF Fleet, E Gilbertson, A Chatraphorn, S Tralshawala, N Weinstock, H Wellstood, FC TI Imaging defects in Cu-clad NbTi wire using a high-T-c scanning SQUID microscope SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE non-destructive evaluation; SQUID; superconducting; wires ID QUANTUM INTERFERENCE DEVICE AB We have used a sensitive magnetic microscope based on the de Superconducting Quantum Interference Device (SQUID) to examine room-temperature samples of Cu-cladNbTi wire, Our SQUID microscope allows the wire (in air at room temperature) to be brought to within about 0.05 mm of the SQUID, although typically the separation is 0.3-0.4 mm, The wires have round or rectangular cross-sections and are about 2 mm across, With the wire aligned parallel to the x-direction in the x-y scanning plane we apply currents of a few mA through the wire at a frequency of a few hundred Hz, and image the x-component of the magnetic field. Defects cause a redistribution of current and corresponding features in the magnetic field image. We show images of wires, and discuss the advantages of using the parallel component of the field. C1 Univ Maryland, Ctr Superconduct Res, Dept Phys, College Pk, MD 20742 USA. Raytheon ITSS, Lanham, MD USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. USAF, Off Sci Res, Arlington, VA 22203 USA. RP Fleet, E (reprint author), Univ Maryland, Ctr Superconduct Res, Dept Phys, College Pk, MD 20742 USA. RI Joint Quantum Institute, NIST/UMD/H-4494-2011 NR 9 TC 3 Z9 4 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 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 215 EP 218 DI 10.1109/77.919322 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400041 ER PT J AU Caputo, P Ustinov, AV Yukon, SP AF Caputo, P Ustinov, AV Yukon, SP TI Enhanced microwave power from triangular arrays of small Josephson junctions SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE superconducting devices; Josephson devices; Josephson arrays; millimeter wave devices AB We report on high frequency measurements of underdamped Josephson junction arrays consisting of two rows of parallel biased cells. The rf voltage generated on the junctions transverse to the bias current (horizontal junctions) is detected by a room temperature receiver in the W-band. In order to enhance the emitted power, it has been proposed (S.P.Y.) that the single horizontal junction in each cell be replaced by two (or more) horizontal junctions. This geometry has been proven to have better high frequency performance, Here we present comparative measurements of the output power from two row arrays of different geometries. Among the studied configurations, larger power is obtained from an array with square cells and two horizontal junctions. In this array, the measured output power is up to about 2 times larger than that in the array with only one horizontal junction, and up to 20 times larger with respect to the array with conventional triangular cells. Experimental data are in good qualitative agreement with numerical simulations. C1 Univ Salerno, Dipartimento Fis, I-84081 Baronissi, Italy. Univ Erlangen Nurnberg, Inst Phys 3, D-91058 Erlangen, Germany. USAF, Res Lab, SNHE, Hanscom AFB, MA 01731 USA. RP Caputo, P (reprint author), Univ Salerno, Dipartimento Fis, I-84081 Baronissi, Italy. NR 10 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 454 EP 458 DI 10.1109/77.919381 PN 1 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400100 ER PT J AU Yukon, SP Lin, FC AF Yukon, SP Lin, FC TI Phase shifting in a Josephson junction active antenna array SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Josephson devices; antenna arrays AB We present a design for an active antenna array employing triangular Josephson junction (JJ) sub-arrays as rf oscillator sources. The sub-arrays are kept in sync by coupling to a closed serpentine discrete JJ ladder. Phase shifts are introduced by adding external magnetic flux into the JJ ladders between sub-arrays, Phase shifting distortions are minimized by allowing only two contiguous sub-arrays on any row segment. C1 USAF, Res Lab, SNHE, Hanscom AFB, MA 01731 USA. ARCON Corp, Waltham, MA 02451 USA. RP Yukon, SP (reprint author), USAF, Res Lab, SNHE, Hanscom AFB, MA 01731 USA. NR 4 TC 0 Z9 0 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 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 459 EP 462 DI 10.1109/77.919382 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HP UT WOS:000168285400101 ER PT J AU Haugan, T Wong-Ng, W Cook, LP Geyer, RG Brown, HJ Swartzendruber, L Kaduk, J AF Haugan, T Wong-Ng, W Cook, LP Geyer, RG Brown, HJ Swartzendruber, L Kaduk, J TI Development of low cost (Sr,Ca)(3)Al2O6 dielectrics for Bi2Sr2CaCu2O8+delta applications SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE Bi2Sr2CaCu2O8+delta; dielectric constant and loss tangent; (Sr,Ca)(3)Al2O6; tie-line phase equilibrium ID CU-O SYSTEM; CRYOGENIC TEMPERATURES; SINGLE-CRYSTALS; THICK-FILMS; T-C; ALUMINA; SUPERCONDUCTOR; ADDITIONS; AL2O3; POLARIZABILITIES AB Aspects of the development of low-cost (Sr,Ca)(3)Al2O6 dielectrics for Bi2Sr2CaCu2O8+delta superconductor applications were investigated. A tie-line phase equilibrium relationship between Bi2Sr2CaCu2O8+delta and Sr2CaAl2O6 compositions was observed at 860 degreesC. When the Bi-2212 and (Sr,Ca)(3)Al2O6 solid-solution compositions were changed slightly, the tie-line relationship was not preserved, and a new phase was observed to form with composition similar to BiSr1.5Ca0.5Al2Ox. Composites of (0 to 24) volume fraction % Sr2CaAl2O6 + Bi2Sr2CaCu2O8+delta equilibrated at 860 degreesC slightly reduced the T-c (by 2 g to 4 K) and superconducting volume percentage of the 2212 phase. The dielectric properties of (Sr = 1.0 to 2.5) members of solid-solution (Sr,Ca)(3)Al2O6 were measured at 77 K and 297 K in the range of (10 to 11) GHz for cylindrical samples using resonant system methods. The dielectric constant epsilon (r) varied from 9.7 to 13.2, and the loss tangent tan delta was from 3 x 10(-4) to 8 x 10(-4). C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. BP Amoco Chem, Naperville, IL 60566 USA. RP Haugan, T (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 26 TC 2 Z9 2 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 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3305 EP 3308 DI 10.1109/77.919769 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900153 ER PT J AU Nekkanti, RM Seetharaman, V Brunke, L Maartense, I Dempsey, D Kozlowski, G Tomich, D Biggers, R Peterson, T Barnes, P Oberly, CE AF Nekkanti, RM Seetharaman, V Brunke, L Maartense, I Dempsey, D Kozlowski, G Tomich, D Biggers, R Peterson, T Barnes, P Oberly, CE TI Development of nickel alloy substrates for Y-Ba-Cu-O coated conductor applications SO IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY LA English DT Article; Proceedings Paper CT 2000 Applied Superconductivity Conference CY SEP 17-22, 2000 CL VIRGINIA BEACH, VIRGINIA DE HTS; nickel alloy substrates; Ni-Cr; Orientation Imaging Microscopy (OIM); YBCO ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; FILMS AB Fabrication of long-length, textured substrates constitute a critical step in the successful application of coated High Temperature Superconductors (HTS). Substrate materials stronger than nickel are needed for robust applications, while substrates with non-magnetic characteristics are preferred for AC applications The present work is thus focused on development of texture in high strength, non-magnetic substrate materials As the development of cube texture is easier in medium to high stacking fault energy materials, binary alloys based on nickel were evaluated for the present application. High purity alloys were melted and hot/cold worked to obtain thin tapes. The development of texture in these alloys as a function of processing parameters was studied by x-ray diffraction and metallographic technique. Orientation Imaging Microscopy (OIM) was used to quantify the extent of texture development in these substrates. Results to date on the development of texture by thermo-mechanical processing of these alloys are presented. C1 UES Inc, Dayton, OH 45432 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. Wright State Univ, Fairbom, OH 45324 USA. USAF, Res Labs, Wright Patterson AFB, OH 45433 USA. RP Nekkanti, RM (reprint author), UES Inc, Dayton, OH 45432 USA. NR 8 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 1051-8223 J9 IEEE T APPL SUPERCON JI IEEE Trans. Appl. Supercond. PD MAR PY 2001 VL 11 IS 1 BP 3321 EP 3324 DI 10.1109/77.919773 PN 3 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 425HV UT WOS:000168285900157 ER PT J AU Anwar, AFM Wu, SL Webster, RT AF Anwar, AFM Wu, SL Webster, RT TI Temperature dependent transport properties in GaN, A1(x)Ga(1-x)N, and InxGa1-xN semiconductors SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE AlGaN; electron transport; InGaN ID MONTE-CARLO CALCULATION; ELECTRON-TRANSPORT; GALLIUM NITRIDE; BAND-STRUCTURE; ZINCBLENDE AB Ensemble Monte Carlo simulation is used to determine the electron saturation velocity and low-field mobility for AlxGa1-xN and InxGa1-xN. Acoustic phonon, optical phonon, intervalley, ionized impurity, alloy, and piezoelectric scattering are included in the simulation. Doping concentration ranging from 10(17) cm(-3) to 10(19) cm(-3) is considered in the temperature range of 50 K to 500 K, Theoretical calculation shows excellent agreement with low-field mobility experimental data. Empirical expressions for low field mobility and saturation velocity are provided as functions of temperature, doping concentration and mole fraction. C1 Univ Connecticut, Dept Elect & Comp Engn, Storrs, CT 06269 USA. USAF, Div Electromagnet Technol, Sensors Directorate, Res Lab, Hanscom AFB, MA 01730 USA. RP Anwar, AFM (reprint author), Univ Connecticut, Dept Elect & Comp Engn, Storrs, CT 06269 USA. NR 15 TC 47 Z9 48 U1 0 U2 13 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD MAR PY 2001 VL 48 IS 3 BP 567 EP 572 DI 10.1109/16.906452 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 407CC UT WOS:000167253000027 ER PT J AU Igelnik, B Tabib-Azar, M LeClair, SR AF Igelnik, B Tabib-Azar, M LeClair, SR TI A net with complex weights SO IEEE TRANSACTIONS ON NEURAL NETWORKS LA English DT Article DE adaptive stochastic optimization; basis functions; complex weights; ensemble of nets; recursive linear regression ID FUNCTION APPROXIMATION; NEURAL NETWORKS; BACKPROPAGATION; SUPERPOSITIONS; REGRESSION AB In this article a new neural-network architecture suitable for learning and generalization is discussed and developed, Although similar to the radial basis function (RBF) net, our computational model called the net with complex weights (CWN) has demonstrated a considerable gain in performance and efficiency in number of applications compared to REP net. Its better performance in classification tasks is explained by the cross-product terms in internal representation of its basis function introduced parsimoniously. Implementation of CWN by the ensemble approach is described. A number of examples, solved using CWN and other networks, are used to illustrate the desirable characteristics of CWN. C1 Pegasus Technol Inc, Mentor, OH 44060 USA. Case Western Reserve Univ, Elect Engn & Comp Sci Dept, Cleveland, OH 44106 USA. MLIM, Wright Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Igelnik, B (reprint author), Pegasus Technol Inc, Mentor, OH 44060 USA. NR 30 TC 13 Z9 13 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 1045-9227 J9 IEEE T NEURAL NETWOR JI IEEE Trans. Neural Netw. PD MAR PY 2001 VL 12 IS 2 BP 236 EP 249 DI 10.1109/72.914521 PG 14 WC Computer Science, Artificial Intelligence; Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 418JG UT WOS:000167886700005 PM 18244381 ER PT J AU Boinard, P Pethrick, RA Banks, WM Crane, RL AF Boinard, P Pethrick, RA Banks, WM Crane, RL TI Novel non-destructive technique to assess the degradation of adhesively bonded composite structures SO INSIGHT LA English DT Article AB This paper describes how; dielectric spectroscopy, techniques can be successfully applied to the study, of carbon fibre reinforced plastics (CFRP) adhesively, bonded structures. Carbon fibre is less conductive than aluminium. It is, however, sufficiently conductive to sustain the propagation of low- and high-frequency dielectric signals. The use of dielectric spectroscopy to monitor non-destructively the ingress of water into adhesively bonded CFRP composite structures will be explained and the correlation between the degradation of the adhesive properties of the joint during ageing due ro water absorption and the dielectric sperm spectroscopy measurements will be presented. Furthermore, the potential of th is NDE method to assess the quality of joint structures will be shown. C1 Univ Strathclyde, Glasgow G1 1XL, Lanark, Scotland. USAF, Nondestruct Evaluat Branch, Mat Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Boinard, P (reprint author), Univ Strathclyde, Thomas Graham Bldg,295 Cathedral St, Glasgow G1 1XL, Lanark, Scotland. NR 11 TC 4 Z9 4 U1 2 U2 5 PU BRITISH INST NON-DESTRUCTIVE TESTING PI NORTHAMPTON PA 1 SPENCER PARADE, NORTHAMPTON NN1 5AA, NORTHANTS, ENGLAND SN 1354-2575 J9 INSIGHT JI Insight PD MAR PY 2001 VL 43 IS 3 BP 159 EP 162 PG 4 WC Instruments & Instrumentation; Materials Science, Characterization & Testing SC Instruments & Instrumentation; Materials Science GA 410FT UT WOS:000167430500014 ER PT J AU Iyer, K AF Iyer, K TI Peak contact pressure, cyclic stress amplitudes, contact semi-width and slip amplitude: relative effects on fretting fatigue life SO INTERNATIONAL JOURNAL OF FATIGUE LA English DT Article DE fatigue; fretting; life-production AB Using Hertzian relationships and a finite element model of a cylinder-on-flat contact configuration, a set of critical fretting fatigue experiments have been conducted to determine the relative effects of six local mechanistic parameters on fretting fatigue life. The six parameters evaluated are: (i) the peak contact pressure, p(0); (ii) the maximum local cyclic bulk stress range, Delta sigma (L,max); (iii) the maximum, local cyclic shear stress, tau (L,max); (iv) the maximum, local cyclic shear stress range, Delta tau (L,max); (v) the maximum slip amplitude, delta (max); and (vi) the contact semi-width, a. The findings are significant. Only the peak contact pressure and the local, maximum bulk stress range have direct effects on fretting fatigue life. The fretting fatigue life is found to have a previously unknown positive, exponential dependence on the peak contact pressure, which enables an elegant recovery of a standard ('plain') fatigue life equation. Additionally, interfacial shear tractions appear to have no effect on the life. Although some of the remaining four parameters can be correlated to fretting fatigue life, it is likely through their relationships to either the peak contact pressure or the local, maximum bulk stress range. These inter-relationships have been outlined for a cylinder-on-flat geometry and a general, physically based fretting fatigue life equation has been developed. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Iyer, K (reprint author), USAF, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RI Iyer, Kaushik/H-1411-2016 NR 17 TC 21 Z9 23 U1 1 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-1123 J9 INT J FATIGUE JI Int. J. Fatigue PD MAR PY 2001 VL 23 IS 3 BP 193 EP 206 DI 10.1016/S0142-1123(00)00092-X PG 14 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 403UX UT WOS:000167061800002 ER PT J AU Ruschau, JJ Nicholas, T Thompson, SR AF Ruschau, JJ Nicholas, T Thompson, SR TI Influence of foreign object damage (FOD) on the fatigue life of simulated Ti-6Al-4V airfoils SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article AB The fatigue behavior of Ti-6Al-4 V samples that have undergone foreign object damage (FOD) was investigated. A unique test specimen configuration that replicates the leading edge of a typical fan blade was ballistically shot with 1.0 mm diameter glass spheres to simulate actual FOD. Samples were shot at various incident angles to investigate the influence of impact angle on fatigue strength. Two stress ratios were examined: R = 0.1 and 0.5. Attempts were made to correlate the measured damage (macro-/microscopic) to the debit in fatigue strength. The FOD impact sites of fatigue samples were examined prior to testing via a scanning electron microscope (SEM); post-test examinations of the fatigue initiation sites were also performed on selected test samples. Subsurface or internal damage resulting from the FOD was also investigated from precision micro-sectioning of selected samples. Oh-angle impacts were found to be more detrimental than head-on (0 degrees) impacts. Fatigue strength losses, some as high as 50%, showed little or no correlation with leading edge thickness or depth of notch. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Ruschau, JJ (reprint author), Univ Dayton, Res Inst, 300 Coll Pk, Dayton, OH 45469 USA. NR 15 TC 28 Z9 32 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD MAR PY 2001 VL 25 IS 3 BP 233 EP 250 DI 10.1016/S0734-743X(00)00044-0 PG 18 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 396GF UT WOS:000166627400002 ER PT J AU Bolt, PJ AF Bolt, PJ TI Economic ties across the Taiwan Strait: Buying time for compromise SO ISSUES & STUDIES LA English DT Article DE China; Taiwan; investment; trade; electronics industry AB This work explores the way in which Taiwan's extensive economic interactions with the mainland affect cross-Strait relations. These economic interactions occur not only within a context of mainland-Taiwan political tension, but also within a broader environment of economic globalization wherein the international community is dependent on economic output from both sides of the Taiwan Strait. The paper begins by examining Beijing's and Taipei's views and policies toward cross-Strait economic exchanges. While Beijing sees economic exchanges as beneficial for both reunification with Taiwan and economic growth, Taipei worries that the pace of economic exchange reduces the island's security and political flexibility. The second section lays out the details of increasing trade and investment across the Taiwan Strait, while the third part looks at Taiwanese investments in the electronic sector The final section assesses the impact of economic exchange on cross-Strait relations. This work argues that a web of investment and trade is increasingly tying Taiwan and the mainland to each other and the international division of labor. These links make disruptive political action on the part of the mainland or Taiwan increasingly costly for both primary players, as well os the international economy, and thus serve to reinforce the political status quo. RP Bolt, PJ (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 81 TC 7 Z9 7 U1 0 U2 2 PU INST INTERNAT RELATIONS PI MUCHA PA 64 WAN SHOU ROAD, MUCHA, TAIPEI, TAIWAN SN 1013-2511 J9 ISSUES STUD JI Issues Stud. PD MAR-APR PY 2001 VL 37 IS 2 BP 80 EP 105 PG 26 WC Area Studies; International Relations; Political Science SC Area Studies; International Relations; Government & Law GA 443FA UT WOS:000169329000003 ER PT J AU Thompson, W AF Thompson, W TI American airpower strategy in Korea, 1950-1953. SO JOURNAL OF AMERICAN HISTORY LA English DT Book Review C1 AF Hist Support Off, Bolling AFB, DC USA. RP Thompson, W (reprint author), AF Hist Support Off, Bolling AFB, DC USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ORGANIZATION AMER HISTORIANS PI BLOOMINGTON PA 112 N BRYAN ST, BLOOMINGTON, IN 47408 USA SN 0021-8723 J9 J AM HIST JI J. Am. Hist. PD MAR PY 2001 VL 87 IS 4 BP 1565 EP 1565 DI 10.2307/2674872 PG 1 WC History SC History GA 416RK UT WOS:000167793800150 ER PT J AU Ryan, KL Tehrany, MR Jauchem, JR AF Ryan, KL Tehrany, MR Jauchem, JR TI Nitric oxide does not contribute to the hypotension of heatstroke SO JOURNAL OF APPLIED PHYSIOLOGY LA English DT Article DE environmental heating.; hyperthermia; heat stress; blood pressure ID ARGININE METHYL-ESTER; RAT MESENTERIC-ARTERIES; SEPTIC SHOCK; HEAT-STRESS; CIRCULATORY FAILURE; L-NAME; SYNTHESIS INHIBITION; HEMORRHAGIC-SHOCK; BLOOD-FLOW; HYPERTHERMIA AB The purpose of this study was to determine whether nitric oxide (NO) contributes to the hypotensive state induced by prolonged environmental heat (EW) stress. Ketamine-anesthetized rats were instrumented for the measurement of arterial blood pressure, electrocardiogram, and temperature at four sites. Rats were exposed to EH (ambient temperature, 40 +/- 1 degreesC) until mean arterial blood pressure (MAP) decreased to 75 mmHg, which was arbitrarily defined as the induction of heatstroke. In addition to cardiovascular and temperature measurements, the time required to reach this MAP end point and the subsequent survival time were measured. In three separate experimental series, the competitive NO synthesis inhibitor N-omega-nitro-L-arginine methyl ester (L-NAME) was administered (0, 10, or 100 mg/kg) either before, during (30 min after initiation of EH), or immediately after EH. L-NAME administered at any of these times transiently increased MAP. L-NAME infusion either before or during EH did not alter the EH time required to decrease MAP to 75 mmHg, but L-NAME pretreatment did decrease the colonic temperature at which this MAP end point was reached. L-NAME infusion before or after EH did not affect subsequent survival time, but L-NAME administered during EH significantly decreased survival time. The administration of L-NAME at any time point, therefore, did not prove beneficial in either preventing or reversing heatstroke. Taken together, these data suggest that NO does not mediate the hypotension associated with heatstroke. C1 USAF, Res Lab, Human Effectiveness Directorate, Directed Energy Bioeffects Div, Brooks AFB, TX 78235 USA. Trinity Univ, Dept Biol, San Antonio, TX 78212 USA. RP Jauchem, JR (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Directed Energy Bioeffects Div, 8315 Hawks Rd, Brooks AFB, TX 78235 USA. NR 54 TC 12 Z9 16 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 8750-7587 J9 J APPL PHYSIOL JI J. Appl. Physiol. PD MAR PY 2001 VL 90 IS 3 BP 961 EP 970 PG 10 WC Physiology; Sport Sciences SC Physiology; Sport Sciences GA 403PJ UT WOS:000167051400028 PM 11181607 ER PT J AU Bronk, BV Li, ZZ Czege, J AF Bronk, BV Li, ZZ Czege, J TI Polarized light scattering as a rapid and sensitive assay for metal toxicity to bacteria SO JOURNAL OF APPLIED TOXICOLOGY LA English DT Article DE toxicity to bacteria; polarized light scattering; E. coli; heavy metals; rapid detection; metal toxicity; growth inhibition ID SIZE AB A new method that utilizes the scattering of polarized light from a suspension of bacteria to assay the effect of toxins is evaluated. The method compares the time dependence of changes in an angular scattering pattern obtained from a suspension of Escherichia coli bacteria with no toxin exposure to the corresponding, but reduced, changes that occur when there is exposure to a small concentration of certain toxicants. The changes are due to growth of a specially prepared population of these bacteria. The changes in the pattern normally reflect a change in average bacterial size due to growth, whereas the reduction of the change in pattern occurs when there is rapid cessation of bacterial growth. The method was tested with varying concentrations of the ions of five different heavy metals. The results using this method during the first few minutes after exposure to the toxicant were compared to the relative survival of colony-forming units of the bacteria. The graphs for the two methods were found to he approximately parallel for each of the five metals examined. This result indicates that the toxic effect of these metals takes place relatively quickly for these bacteria. These results were compared with results available from the literature for the same metals but using other methods for measuring the toxicity to bacteria. C1 USA ECBC, USAF, Res Lab, AMSSB RRT, Aberdeen Proving Ground, MD 21010 USA. Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA. RP Bronk, BV (reprint author), USA ECBC, USAF, Res Lab, AMSSB RRT, Bldg E5951, Aberdeen Proving Ground, MD 21010 USA. NR 17 TC 14 Z9 16 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0260-437X J9 J APPL TOXICOL JI J. Appl. Toxicol. PD MAR-APR PY 2001 VL 21 IS 2 BP 107 EP 113 DI 10.1002/jat.730 PG 7 WC Toxicology SC Toxicology GA 418WE UT WOS:000167916500004 PM 11288133 ER PT J AU Silverman, SM Cliver, EW AF Silverman, SM Cliver, EW TI Low-latitude auroras: the magnetic storm of 14-15 May 1921 SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article; Proceedings Paper CT Meeting of the International-Union-of-Geodesy-and-Geophysics (IUGG) CY JUL 27-28, 1999 CL UNIV BIRMINGHAM, BIRMINGHAM, ENGLAND SP Int Union Geodesy & Geophys HO UNIV BIRMINGHAM DE aurora; magnetic storm AB We review solar/geophysical data relating to the great magnetic storm of 14-15 May 1921, with emphasis on observations of the low-latitude visual aurora. From the reports we have gathered for this event, the lowest geomagnetic latitude of definite overhead aurora (coronal form) was 40 degrees and the lowest geomagnetic latitude from which auroras were observed on the poleward horizon in the northern hemisphere was 30 degrees. For comparison, corresponding overhead low-latitude values of 48 degrees /32 degrees and 41 degrees /20 degrees were reported for the great auroras on 28-29 August and 1-2 September 1859, respectively. However, for the 1921 event, there is a report of aurora from Apia, Samoa, in the southern hemisphere, within 13 degrees of the geomagnetic equator. This report by professional observers appears to be credible, based on the aurora description and timing, but is puzzling because of the discrepancy with the lowest latitude of observation in the northern hemisphere and the great implied auroral height (similar to 2000 km, assuming overhead aurora at Auckland, New Zealand). We discuss various possibilities that might account for this observation. (C) 2001 Published by Elsevier Science Ltd. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Silverman, SM (reprint author), 18 Ingleside Rd, Lexington, MA 02420 USA. NR 38 TC 25 Z9 25 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD MAR PY 2001 VL 63 IS 5 BP 523 EP 535 DI 10.1016/S1364-6826(00)00174-7 PG 13 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 422HV UT WOS:000168113200016 ER PT J AU Langhoff, PW Arce, JC Sheehy, JA Hemmers, O Wang, H Focke, P Sellin, IA Lindle, DW AF Langhoff, PW Arce, JC Sheehy, JA Hemmers, O Wang, H Focke, P Sellin, IA Lindle, DW TI On the angular distributions of electrons photoejected from fixed-in-space and randomly oriented molecules SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article; Proceedings Paper CT 8th International Conference on Electronic Spectroscopy and Structure CY AUG 08-12, 2000 CL UNIV CALIF, CLARK KERR CAMPUS, BERKELEY, CALIFORNIA HO UNIV CALIF, CLARK KERR CAMPUS ID K-SHELL PHOTOIONIZATION; X-RAY PHOTOEMISSION; DIPOLE APPROXIMATION; MULTIPOLE CORRECTIONS; 1S PHOTOELECTRONS; N-2 MOLECULES; CO MOLECULES; LOW ENERGIES; NITROGEN; PHOTOABSORPTION AB New theoretical expressions are devised from a dynamical perspective for molecular photoionization cross sections differential in electron ejection angles which facilitate comparisons between theory and experiment and provide a convenient basis for ab initio calculations. The cross sections obtained for fixed-in-space molecules, including the lowest-order (nondipole) effects of retardation, are given in terms of invariant molecular body-frame transition moments and related normalized angular-distribution amplitudes which can be calculated employing interaction-prepared states without reference to specific scattering boundary conditions. Corresponding expressions for molecular dipole and nondipole anisotropy factors appropriate for randomly oriented molecules are obtained in closed forms involving expectation values of harmonic polynomials over the fixed-in-space body-frame angular-distribution amplitudes. The expressions are seen to be in the spirit of corresponding results for atomic photoionization anisotropy factors, to which they reduce in appropriate limits. Interpretations of recently measured angular distributions of photoelectrons from the K-shell of molecular nitrogen illustrate how the development relates measurements on randomly oriented molecules to those performed on fixed-in-space molecules. The theoretical formalism provides results in excellent accord with measurements of the molecular nitrogen K-shell dipole anisotropy factor, and accounts for the origins of large nondipole effects observed at relatively low photon energies ((h) over bar omega 5000 less than or equal to eV) in the measured angular distributions. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, San Diego Supercomp Ctr, La Jolla, CA 92093 USA. Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. USAF, Res Lab, AFRL, PRS, Edwards AFB, CA 93524 USA. Univ Valle, Dept Quim, Cali 25360AA, Colombia. Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. Univ Lund, MAX Lab, S-22100 Lund, Sweden. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. RP Langhoff, PW (reprint author), Univ Calif San Diego, San Diego Supercomp Ctr, 9500 Gilman Dr, La Jolla, CA 92093 USA. NR 44 TC 24 Z9 24 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD MAR PY 2001 VL 114 BP 23 EP 32 DI 10.1016/S0368-2048(00)00418-7 PG 10 WC Spectroscopy SC Spectroscopy GA 417JW UT WOS:000167832700005 ER PT J AU Adesida, I Redwing, J Rea, L Zetterling, CM AF Adesida, I Redwing, J Rea, L Zetterling, CM TI Special issue on III-V nitrides and silicon carbide - Foreword SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Editorial Material C1 Univ Illinois, Urbana, IL 61801 USA. Penn State Univ, University Pk, PA 16802 USA. USAF, Res Lab, Wright Patterson AFB, OH USA. KTH Royal Inst Technol, Trondheim, Norway. RP Adesida, I (reprint author), Univ Illinois, Urbana, IL 61801 USA. RI Zetterling, Carl-Mikael/E-5764-2015 OI Zetterling, Carl-Mikael/0000-0001-8108-2631 NR 0 TC 0 Z9 0 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAR PY 2001 VL 30 IS 3 BP 109 EP 109 DI 10.1007/s11664-001-0001-7 PG 1 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 408BR UT WOS:000167307100001 ER PT J AU Lee, CD Ramachandran, V Sagar, A Feenstra, RM Greve, DW Sarney, WL Salamanca-Riba, L Look, DC Bai, S Choyke, WJ Devaty, RP AF Lee, CD Ramachandran, V Sagar, A Feenstra, RM Greve, DW Sarney, WL Salamanca-Riba, L Look, DC Bai, S Choyke, WJ Devaty, RP TI Properties of GaN epitaxial layers grown on 6H-SiC(0001) by plasma-assisted molecular beam epitaxy SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE GaN; SiC; molecular beam epitaxy; dislocation density; scanning tunneling microscopy ID VAPOR-PHASE EPITAXY; OPTICAL-TRANSITIONS; DOPED GAN; SIC(0001); SURFACE; PHOTOLUMINESCENCE; FILMS AB The structural, electrical, and optical properties of GaN grown on 6H-SiC(0001) substrates by molecular beam epitaxy are studied. Suitable substrate preparation and growth conditions are found to greatly improve the structural quality of the films. Threading dislocation densities of about 3 x 10(9) cm(-2) for edge dislocations and < 1 x 10(6) cm(-2) for screw dislocations are achieved in GaN films of 0.8 m thickness. Mechanisms of dislocation generation and annihilation are discussed. Increasing the Ga to N flux ratio used during growth is found to improve the surface morphology, An unintentional electron concentration in the films of about 5 x 10(17) cm(-3) is observed, and is attributed to excess Si in the films due to a Si-cleaning step used in the substrate preparation, Results from optical characterization are correlated with the structural and electronic studies. C1 Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Carnegie Mellon Univ, Dept Elect & Comp Engn, Pittsburgh, PA 15213 USA. Univ Maryland, Mat & Nucl Engn Dept, College Pk, MD 20742 USA. Wright State Univ, Dayton, OH 45435 USA. USAF, Res Lab, Dayton, OH 45435 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. IBM Microelect, Essex Junction, VT 05452 USA. RP Lee, CD (reprint author), Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. RI Salamanca-Riba, Lourdes/B-3785-2009; Feenstra, Randall/P-2530-2014 OI Salamanca-Riba, Lourdes/0000-0001-8155-6403; Feenstra, Randall/0000-0001-7120-5685 NR 26 TC 19 Z9 19 U1 1 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAR PY 2001 VL 30 IS 3 BP 162 EP 169 DI 10.1007/s11664-001-0010-6 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 408BR UT WOS:000167307100010 ER PT J AU Saddow, SE Schattner, TE Brown, J Grazulis, L Mahalingam, K Landis, G Bertke, R Mitchel, WC AF Saddow, SE Schattner, TE Brown, J Grazulis, L Mahalingam, K Landis, G Bertke, R Mitchel, WC TI Effects of substrate surface preparation on chemical vapor deposition growth of 4H-SiC epitaxial layers SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE chemical mechanical polishing; silicon carbide; atomic force microscopy; surface morphology ID SILICON-CARBIDE; OHMIC CONTACTS AB The effects of chemical mechanical polish (CMP) and pre-growth oxidation and etching of vicinal 4H-SiC substrates on the quality of epitaxial films have been investigated. Samples with and without a collodial silica CMP and oxidation/etch treatment were studied with optical microscopy, cross section transmission electron microscopy (TEM) and atomic force microscopy (AFM) before and after chemical vapor deposition. Evidence of polishing damage was evident prior to growth in all samples without CMP treatment. Oxidation and etching appeared to generate defects by preferential etching of bulk defects such as dislocations and low angle grain boundaries. Evidence of the polishing damage remained after chemical vapor deposition (CVD) growth on the samples without CMP and the defect density was worse for the oxidized samples compared to the unoxidized ones. The unoxidized CMP wafer had the lowest defect density and rms roughness of the samples studied. C1 Mississippi State Univ, Emerging Mat Res Lab, Mississippi State, MS 39726 USA. USAF, Res Lab, MLP, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Dayton, OH 45469 USA. RP Saddow, SE (reprint author), Mississippi State Univ, Emerging Mat Res Lab, Mississippi State, MS 39726 USA. NR 14 TC 26 Z9 27 U1 1 U2 9 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAR PY 2001 VL 30 IS 3 BP 228 EP 234 DI 10.1007/s11664-001-0021-3 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 408BR UT WOS:000167307100021 ER PT J AU Chen, JK Beraun, JE Tzou, DY AF Chen, JK Beraun, JE Tzou, DY TI A dual-phase-lag diffusion model for predicting intermetallic compound layer growth in solder joints SO JOURNAL OF ELECTRONIC PACKAGING LA English DT Article ID TIN-RICH SOLDERS; INTERFACIAL REACTIONS; TEMPERATURE; COPPER AB A dual-phase-lag diffusion (DPLD) model is presented for predicting the intermetallic compound (IMC) layer growth in solder joints. It extends from Fick's law by taking into account the delayed response between the interdiffusion of two dissimilar materials and the chemical reaction that forms the IMC. The merit of this model is that it uniquely represents four different types of IMC growth kinetics, all of which are found in the literature. Comparison between the model and experimental results for 100Sn/Cu and Ag/Zn systems demonstrates that the proposed DPLD model captures the growth history of IMC layers quite well. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Univ Missouri, Dept Mech & Aerosp Engn, Columbia, MO 65211 USA. RP Chen, JK (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 19 TC 14 Z9 14 U1 1 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 1043-7398 J9 J ELECTRON PACKAGING JI J. Electron. Packag. PD MAR PY 2001 VL 123 IS 1 BP 52 EP 57 DI 10.1115/1.1326438 PG 6 WC Engineering, Electrical & Electronic; Engineering, Mechanical SC Engineering GA 412RK UT WOS:000167568000008 ER PT J AU Pachter, M D'Azzo, JJ Proud, AW AF Pachter, M D'Azzo, JJ Proud, AW TI Tight formation flight control SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article AB The tight formation flight control problem is addressed. The formation consists of a lead and wing aircraft, where the wing flies in tight formation with the lead, such that the lead's trailing vortices aerodynamically couple the lead and the wing, and a reduction in the formation's induced drag is achieved. A controller (i.e., a formation-hold autopilot for the wing aircraft) is designed such that the formation's geometry is maintained in the fate of lead aircraft maneuvers. In the formation flight central system, the wing and lead aircraft dynamics are coupled due to kinematic effects, and, in the case of tight formations, additional aerodynamic coupling effects are introduced. These additional aerodynamic coupling effects are properly modeled. The most significant aerodynamic coupling effect introduced by tight formation flight entails the coupling of the lateral/directional channel into the altitude-hold autopilot channel. It is shown that formation-hold autopilots designed ignoring the aerodynamic coupling effect yield satisfactory performance in tight formation flight. C1 USAF, Inst Technol, Dept Elect Engn, Wright Patterson AFB, OH 45433 USA. USAF, Inst Technol, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Pachter, M (reprint author), USAF, Inst Technol, Dept Elect Engn, Wright Patterson AFB, OH 45433 USA. NR 10 TC 74 Z9 80 U1 0 U2 5 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAR-APR PY 2001 VL 24 IS 2 BP 246 EP 254 DI 10.2514/2.4735 PG 9 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 410WA UT WOS:000167463000008 ER PT J AU Kang, W Sparks, A Banda, S AF Kang, W Sparks, A Banda, S TI Coordinated control of multisatellite systems SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article ID SATELLITES AB The problem of formation and reconfiguration of multiple microsatellite systems is addressed. A control scheme called the perceptive frame is adopted that integrates the decentralized feedback of each satellite with online sensor information to achieve the goal of formation keeping and intersatellite coordination. The proposed design algorithm has the advantage of relative position keeping and easy formation reconfiguration. C1 USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. USAF, Res Lab, Control Sci Div, Wright Patterson AFB, OH 45433 USA. RP Kang, W (reprint author), USN, Postgrad Sch, Dept Math, Monterey, CA 93943 USA. NR 15 TC 43 Z9 45 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD MAR-APR PY 2001 VL 24 IS 2 BP 360 EP 368 DI 10.2514/2.4720 PG 9 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 410WA UT WOS:000167463000021 ER PT J AU Ender, PT Phares, J Gerson, G Taylor, SE Regnery, R Challener, RC Dolan, MJ AF Ender, PT Phares, J Gerson, G Taylor, SE Regnery, R Challener, RC Dolan, MJ TI Association of Bartonella species and Coxiella burnetii infection with coronary artery disease SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID ROCHALIMAEA-HENSELAE; HEART-DISEASE; COHORT; CELLS; MEN AB Coronary artery disease is an inflammatory condition associated with several infections. We prospectively evaluated 155 consecutive patients undergoing coronary angiography for evidence of Bartonella species and Coxiella burnetii infection. All Bartonella cultures were found to be negative. Multivariable logistic regression analysis that controlled for potential confounding factors revealed no association between coronary artery disease and seropositivity to Bartonella henselae (odds ratio [OR], 0.852; 95% confidence interval [CI], 0.293-2.476), Bartonella quintana (OR, 0.425; 95% CI, 0.127-1.479), C. burnetii phase 1 (OR, undefined), and C. burnetii phase 2 (OR, 0.731; 95% CI, 0.199-2.680). The geometric mean titer (GMT) for C. burnetii phase 1 assay was slightly higher in persons with coronary artery disease than in those without such disease (P < .02). B. henselae, B. quintana, and C. burnetii seropositivity was not strongly associated with coronary artery disease. On the basis of GMTs, C. burnetii infection may have a modest association with coronary artery disease. C1 Wright Patterson Med Ctr, Div Infect Dis, Wright Patterson AFB, OH 45433 USA. Wright Patterson Med Ctr, Div Cardiol, Wright Patterson AFB, OH 45433 USA. Wright Patterson Med Ctr, Dept Internal Med, Wright Patterson AFB, OH 45433 USA. Wright State Univ, Dayton, OH 45435 USA. Ctr Dis Control & Prevent, Atlanta, GA USA. Wilford Hall USAF Med Ctr, Div Infect Dis, Lackland AFB, TX 78236 USA. RP Ender, PT (reprint author), Wright Patterson Med Ctr, Div Infect Dis, 74th MDOS SGOMB,4881 Sugar Maple Dr, Wright Patterson AFB, OH 45433 USA. NR 15 TC 3 Z9 3 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD MAR 1 PY 2001 VL 183 IS 5 BP 831 EP 834 DI 10.1086/318831 PG 4 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA 399WD UT WOS:000166836500022 PM 11181164 ER PT J AU McHugh, CP Ostrander, BF Raymond, RW Kerr, SF AF McHugh, CP Ostrander, BF Raymond, RW Kerr, SF TI Population dynamics of sand flies (Diptera : Psychodidae) at two foci of leishmaniasis in Texas SO JOURNAL OF MEDICAL ENTOMOLOGY LA English DT Article DE Lutzomyia; temporal abundance; population ecology; Texas; leishmaniasis ID LUTZOMYIA-ANTHOPHORA DIPTERA; NEOTOMA-MICROPUS; MEXICANA; TRANSMISSION AB Sand flies were collected at a focus of leishmaniasis in Medina County, TX, from April through October 1997 and at a focus in Bexar County, TX, from April 1988 through December 1999. Lutzomyia diabolica (Hall) were collected from April through November with peak abundance in July. The male:female ratio of Lu, diabolica was 1:6.2. Almost all female Lu, diabolica in the collections were unfed. One gravid Lu. diabolica contained 49 ova. Female Lu. anthophora (Addis) were active from February through December with, three peaks in abundance suggestive of successive generations. Unfed and gravid u. anthophora were collected in about equal numbers. Gravid females contained from Ito 64 ova per female, The male:female ratio was 1:1.8, with male Lu, anthophora collected in all months. One female Ltd. anthophora was found infected with Leishmania in July 1999. Lutzomyia texana (Dampf) were collected from April through October with peak abundance in April during 1997. The male:female ratio was 1:1.4, with most females unfed. Two gravid Lu. texana contained 32 and 102 ova. An undescribed species of Lutzomyia was found only at the Medina County site from May through September 1997. Trapping sites four times per month versus two times per month in 1999 did not appear to adversely affect the abundance of Lu, diabolica or Lu, anthophora. There were marked differences in the species composition and relative abundance at the different sites, indicating that the spatial distribution of sand flies is patchy in nature. C1 Univ Incarnate Word, Dept Biol, San Antonio, TX 78209 USA. RP McHugh, CP (reprint author), USAF, Inst Environm Safety & Occupat Hlth Risk Anal, AFIERA RSRH, 2513 Kennedy Circle, Brooks AFB, TX 78235 USA. FU NIAID NIH HHS [AI 39725]; NIGMS NIH HHS [GM 55337, GM 50089] NR 26 TC 8 Z9 9 U1 0 U2 2 PU ENTOMOL SOC AMER PI LANHAM PA 9301 ANNAPOLIS RD, LANHAM, MD 20706 USA SN 0022-2585 J9 J MED ENTOMOL JI J. Med. Entomol. PD MAR PY 2001 VL 38 IS 2 BP 268 EP 277 DI 10.1603/0022-2585-38.2.268 PG 10 WC Entomology; Veterinary Sciences SC Entomology; Veterinary Sciences GA 414CV UT WOS:000167649100023 PM 11296834 ER PT J AU Eaves, RH Flagg, AJ AF Eaves, RH Flagg, AJ TI The US Air Force Pilot Simulated Medical Unit: A teaching strategy with multiple applications SO JOURNAL OF NURSING EDUCATION LA English DT Article ID COMPREHENSIVE ANESTHESIA SIMULATION AB Historically, Air Force military hospitals have provided excellent training platforms for students and nurses to remain proficient and ready to deliver competent care in a war-time environment. Because of a decrease in the number of admissions, the opportunity to maintain competence is diminishing. The concept of a Simulated Medical Unit (SMU) is being developed at Sheppard Air Force Base, Wichita Falls, Texas to assist in the training and evaluation of such skills. The SMU is a simulation of an actual enactment of an inpatient unit that begins with shift report to the oncoming nursing team. The instructor can then guide the student and team through a series of complex situations using specialized mannequins and live actors as "patients." The student is expected to carry out physicians' orders, perform nursing assessments, document nursing care, as well as administer medications and IV fluids. Scenarios can be made to be as simple or as complex as the situation demands and can be adapted to any specialty. The student can practice technical know-how, sharpen critical thinking abilities, and exercise delegation skills. Should an error occur, the instructor can freeze the moment and assist the student in developing more appropriate choices in their delivery of care. The use of algorithms, performance checklists, and videotaping can be used to evaluate the student's performance. Other adaptations for the SMU can include orientation, cross training into different specialties, competency assessment, and upgrade training. C1 USAF, NC, San Antonio, TX USA. USAF, Sheppard AFB, TX USA. RP Flagg, AJ (reprint author), USAF, NC, 1110 CR 3820, San Antonio, TX USA. NR 13 TC 11 Z9 11 U1 0 U2 0 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 0148-4834 J9 J NURS EDUC JI J. Nurs. Educ. PD MAR PY 2001 VL 40 IS 3 BP 110 EP 115 PG 6 WC Nursing SC Nursing GA 408LM UT WOS:000167327700003 PM 11302538 ER PT J AU Oates, TW Mumford, JH Carnes, DL Cochran, DL AF Oates, TW Mumford, JH Carnes, DL Cochran, DL TI Characterization of proliferation and cellular wound fill in periodontal cells using an in vitro wound model SO JOURNAL OF PERIODONTOLOGY LA English DT Article DE cell division; fibroblasts, gingival/physiology; periodontal ligament/physiology; models, biological; wound healing ID GUIDED TISSUE REGENERATION; ATTACHMENT FORMATION; GROWTH; LIGAMENT; FIBROBLASTS; REPAIR AB Background: The therapeutic success of periodontal regenerative therapy may be compromised by our limited understanding of the wound healing process. Wound healing requires the coordination of complex cellular and molecular interactions. Recently, using an in vitro wound model, our laboratory has shown that gingival fibroblasts (GF) fill an in vitro wound more rapidly than periodontal ligament cells (PDL). This suggests that there may be differences in the levels of proliferation for these 2 cell types during the wound healing process. Such specific cell type differences may be significant in clinical outcomes of regenerative therapy. Therefore, the aim of this research was to characterize and compare the levels of both proliferation and cellular wound fill between GF and PDL using our in vitro wound model. Methods: Primary cultures of human PDL and GF cells were established from explanted tissue, and passaged to 12-well tissue culture plates. Triplicate cultures of both cell types were grown to confluence and in vitro wounds were mechanically created, removing a 3 mm wide band of the cell layer across the diameter of the wells. The wells were then incubated for 2, 6, or 9 days in media containing either 0.1% or 10% fetal bovine serum (FBS). At each time point, cells were pulsed with 5-bromo, 2-deoxyuridine (BrdU), fixed, and nuclei stained to measure DNA synthesis (as a measure for proliferation). Cells were counter stained with cytoplasmic stain to measure cell number. Quantitative analysis distant from (area of interest [AOI 1]), next to (AOI 2), and within the wound boundaries (AOI 3 and 4) was accomplished using computer-assisted histomorphometry. Results: The levels of proliferation and cellular fill for each cell type were assessed relative to time and AOI. Overall, the PDL displayed greater (P <0.01) levels of proliferation than the GF For both cell types, proliferation was found to be significantly (P<0.001) greater at day 2 compared to other time points. PDL displayed greater levels of proliferation than GF in all AOI, with this difference reaching significance (P<0.02) within the cell layer (AOI 1 and 2). When comparing levels of cellular fill in 10% FBS, GF displayed greater wound fill than the PDL. This difference was significant at day 6 (P <0.05) for both the marginal (AOI 3) and central (AOI 4) portions of the wound. Conclusions: These findings, demonstrating unique differences between PDL and GF with respect to proliferation and wound fill in an in vitro model, suggest that there may be cell-specific differences in cellular activity critical to periodontal wound healing. In addition, the results of this study show that the cellular proliferation response may not accurately reflect the overall wound healing response. C1 Univ Texas, Hlth Sci Ctr, Dept Periodont, San Antonio, TX 78229 USA. Wilford Hall USAF Med Ctr, Dept Periodont, San Antonio, TX 78236 USA. RP Oates, TW (reprint author), Univ Texas, Hlth Sci Ctr, Dept Periodont, 7703 Floyd Curl Dr, San Antonio, TX 78229 USA. NR 16 TC 15 Z9 17 U1 1 U2 1 PU AMER ACAD PERIODONTOLOGY PI CHICAGO PA 737 NORTH MICHIGAN AVENUE, SUITE 800, CHICAGO, IL 60611-2690 USA SN 0022-3492 J9 J PERIODONTOL JI J. Periodont. PD MAR PY 2001 VL 72 IS 3 BP 324 EP 330 DI 10.1902/jop.2001.72.3.324 PG 7 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 419KN UT WOS:000167948100006 PM 11327059 ER PT J AU Song, HH Cho, TY Heberer, DP Dang, TD Arnold, FE Tan, LS AF Song, HH Cho, TY Heberer, DP Dang, TD Arnold, FE Tan, LS TI Poly(2,5-dihydroxy-1,4-phenylene benzobisthiazole)/poly(1,4-phenylene benzobisthiazole) copolymers: Chain packing and properties SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE poly(2,5-dihydroxy-1,4-phenylene benzobisthiazole)/poly(1,4-phenylene benzothiazole) copolymers; intramolecular hydrogen bond; pseudoladder chain conformation; chain packing; electrical conductivity ID RIGID-ROD POLYMERS; CONFORMATIONS; TEXTURE AB Crystal-packing, optical, and electrical properties of poly(2,5-dihydroxy-1,4-phenylene benzobisthiazole) (DiOH-PBZT) and copolymers of DiOH-PBZT/poly(1,4-phenylene-benzobisthiazole) (PBZT) were examined. Intramolecular hydrogen bonds between the hydroxyl units and the neighboring nitrogen atoms, as evidenced by the IR spectra, led to the formation of a pseudoladder chain structure and changed the chain packing. The (200) and (010) planes were both affected by the copolymer composition, with the (200) plane spacing increasing from 5.895 to 6.482 Angstrom and the (010) plane spacing decreasing from 3.539 to 3.404 Angstrom with the transition from the unsubstituted PBZT homopolymer to the DiOH-PBZT homopolymer. The cell dimensions of the copolymers were simple averages of those of the individual homopolymers, suggesting the isomorphic crystal structure formation of the two units. The c-axis spacing, how ever, remained unchanged. The increase in the conjugation length of the copolymers as the dihydroxy content increased was confirmed by the bathochromic shift of the absorption band in the ultraviolet-visible spectra. The intrinsic conductivities of the copolymers were 3 orders of magnitude higher than that of the unsubstituted PBZT. (C) 2001 John Wiley & Sons, Inc. C1 Hannam Univ, Dept Polymer Sci & Engn, Daejon, South Korea. Systran Corp, Dayton, OH 45432 USA. USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Song, HH (reprint author), Hannam Univ, Dept Polymer Sci & Engn, 133 Ojung Dong, Daejon, South Korea. RI Tan, Loon-Seng/F-6985-2012 OI Tan, Loon-Seng/0000-0002-2134-9290 NR 25 TC 1 Z9 1 U1 0 U2 2 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 MAR 1 PY 2001 VL 39 IS 5 BP 559 EP 565 DI 10.1002/1099-0488(20010301)39:5<559::AID-POLB1029>3.0.CO;2-S PG 7 WC Polymer Science SC Polymer Science GA 400ZC UT WOS:000166901700010 ER PT J AU Fabian, MK Falk, EA Jumper, EJ AF Fabian, MK Falk, EA Jumper, EJ TI Upstream-propagating potential disturbances interacting with a compressible cascade SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB Phase-locked, unsteady surface-pressure measurements were made at eight suction-side and six pressure-side chord locations on the turning vanes of a compressible cascade. Cascade inlet Mach numbers ranged from 0.427 to 0.500, resulting in a maximum local Mach number through the cascade vane row of 0.730. Unsteady forcing of the cascade Has obtained by von Karman vortex shedding from a row of five circular cylinders positioned 0.80 vane chords downstream of the cascade trailing edge. The resulting measured surface pressures were found to be on the same order of magnitude as those measured previously in forward-forcing studies, in which the circular cylinders were placed 0.80 vane chords upstream of the vane-row leading edge, Frequency decomposition of the rearward-forced surface-pressure signals provided for the construction of disturbance position-vs-phase maps, allowing the measured disturbances to be unambiguously interpreted as potential in nature, originating at the forcing cylinders, and propagating upstream through the vane row at acoustic speeds. The effect of these potential disturbances on the vane-row pressure response was to elicit two, previously unexpected amplification mechanisms: a large-magnitude pressure rise near the vane-row trailing edge and a Mach-number-related, midchord pressure increase known as acoustic blockage. C1 USAF Acad, Dept Aerosp & Mech Engn, Hessert Ctr Aerosp Res, Colorado Springs, CO 80840 USA. Univ Notre Dame, Dept Aerosp & Mech Engn, Hessert Ctr Aerosp Res, South Bend, IN 46556 USA. RP Fabian, MK (reprint author), USAF Acad, Dept Aerosp & Mech Engn, Hessert Ctr Aerosp Res, Colorado Springs, CO 80840 USA. RI Jumper, Eric/A-9856-2013 NR 17 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2001 VL 17 IS 2 BP 240 EP 247 DI 10.2514/2.5762 PG 8 WC Engineering, Aerospace SC Engineering GA 411TZ UT WOS:000167516500003 ER PT J AU Falk, EA Jumper, EJ Fabian, MK Stermer, J AF Falk, EA Jumper, EJ Fabian, MK Stermer, J TI Upstream-propagating potential disturbances in the F109 turbofan engine inlet flow SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB An experimental investigation of the unsteady-velocity field upstream of the single-stage axial fan in a F109 turbofan engine was performed. Phase-locked, three-component velocity measurements were collected at multiple axial, radial, and azimuthal locations directly forward of the fan, out to 1.0 fan-blade chords upstream. The measured velocity data were ensemble averaged and resolved into mean and unsteady components, where the unsteady components were further decomposed into elements of amplitude, frequency, and phase for the primary and first-harmonic frequencies. Analysis of the primary-frequency phase information demonstrated the measured unsteady velocities to be potential in nature, generated by the fan, and to propagate upstream at acoustic speeds into the engine inlet flow. Furthermore, the axial component of the unsteady velocity data was found to exhibit peak-to-peak fluctuations of nearly 20% of the mean-axial velocity very near the fan, whereas the azimuthal (swirl) component exhibited fluctuations reaching nearly 50% of the mean-axial velocity at the same measurement locations, A computational simulation of the velocity field upstream of the F109 fan demonstrated good quantitative agreement with the measured unsteady velocity amplitudes. C1 Univ Notre Dame, Dept Aerosp & Mech Engn, Hessert Ctr Aerosp Res, Notre Dame, IN 46556 USA. USAF Acad Headquarters, Colorado Springs, CO 80840 USA. USAF Acad, Dept Aeronaut, Colorado Springs, CO 80840 USA. RP Falk, EA (reprint author), Univ Notre Dame, Dept Aerosp & Mech Engn, Hessert Ctr Aerosp Res, Notre Dame, IN 46556 USA. RI Jumper, Eric/A-9856-2013 NR 14 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2001 VL 17 IS 2 BP 262 EP 269 DI 10.2514/2.5772 PG 8 WC Engineering, Aerospace SC Engineering GA 411TZ UT WOS:000167516500006 ER PT J AU Strakey, PA Talley, DG Hutt, JJ AF Strakey, PA Talley, DG Hutt, JJ TI Mixing characteristics of coaxial injectors at high gas/liquid momentum ratios SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB A study of the spray of a swirl coaxial gas-liquid injector operating at high gas/liquid momentum ratios is reported, Mixing and droplet size characteristics of the swirl injector are also compared to a shear coaxial injector, currently being used in the space shuttle main engine fuel preburner, The injectors were tested at elevated chamber pressures using water as a liquid oxygen simulant and nitrogen and helium as gaseous hydrogen simulants. The elevated chamber pressure allowed for matching of several of the preburner injector conditions including gas/liquid momentum ratio, density ratio, and Mach number. Diagnostic techniques used to characterize the spray included strobe backlight imaging, laser-sheet spray imaging, mechanical patternation, and phase Doppler interferometry. The results indicate that thr radial spreading of the swirl coaxial spray is much less than was reported in previous studies of swirl injectors operating at atmospheric backpressure, The swirl coaxial spray did, however, exhibit a smaller overall droplet size. C1 USAF, Res Lab, Space & Missile Propuls Div, Aerophys Branch PRSA, Edwards AFB, CA 93524 USA. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Strakey, PA (reprint author), USAF, Res Lab, Space & Missile Propuls Div, Aerophys Branch PRSA, 10 E Saturn Blvd, Edwards AFB, CA 93524 USA. NR 22 TC 12 Z9 13 U1 0 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2001 VL 17 IS 2 BP 402 EP 410 DI 10.2514/2.5756 PG 9 WC Engineering, Aerospace SC Engineering GA 411TZ UT WOS:000167516500024 ER PT J AU Edwards, T Maurice, LQ AF Edwards, T Maurice, LQ TI Surrogate mixtures to represent complex aviation and rocket fuels SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID KINETIC-MODEL; COMBUSTION; TOLUENE AB Surrogate mixtures of one to 10 hydrocarbons that have similar properties to aviation fuels are desirable for experimental and computational tractability and reproducibility, However, aviation fuels, such as Jet A, JP-8, and JP-5, contain hundreds of hydrocarbons, This paper describes appropriate "surrogate" mixtures to reproduce the behavior of multicomponent aviation fuels. Surrogate mixtures from the literature and their applicability to various situations are summarized. C1 USAF, Res Lab, Propuls Directorate, AFRL PRTG, Wright Patterson AFB, OH 45433 USA. USAF, Off Assistant Secretary Acquisit, Div Sci & Technol, SAF AQRT, Washington, DC 20330 USA. RP Edwards, T (reprint author), USAF, Res Lab, Propuls Directorate, AFRL PRTG, 1790 Loop Rd N, Wright Patterson AFB, OH 45433 USA. NR 44 TC 201 Z9 223 U1 6 U2 35 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAR-APR PY 2001 VL 17 IS 2 BP 461 EP 466 DI 10.2514/2.5765 PG 6 WC Engineering, Aerospace SC Engineering GA 411TZ UT WOS:000167516500032 ER PT J AU Koch, PJ Probasco, DP Wolff, JM Copenhaver, WW AF Koch, PJ Probasco, DP Wolff, JM Copenhaver, WW TI Transonic compressor influences on upstream surface pressures with axial spacing SO JOURNAL OF PROPULSION AND POWER LA English DT Article C1 Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. USAF, Res Lab, Propuls Directorate, Turbine Engine Div, Wright Patterson AFB, OH 45433 USA. NASA, Lewis Res Ctr, Res & Technol Directorate, Turbomachinery & Propuls Syst Div, Cleveland, OH 44135 USA. RP Koch, PJ (reprint author), Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. NR 1 TC 2 Z9 2 U1 0 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 MAR-APR PY 2001 VL 17 IS 2 BP 474 EP 476 DI 10.2514/2.5768 PG 3 WC Engineering, Aerospace SC Engineering GA 411TZ UT WOS:000167516500035 ER PT J AU Fiechtner, GJ Gord, JR AF Fiechtner, GJ Gord, JR TI Absorption and the dimensionless overlap integral for two-photon excitation SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE spectral overlap; laser-induced fluorescence; two-photon spectroscopy ID LASER-INDUCED FLUORESCENCE; POWER-SQUARED SENSOR; 2-PHOTON ABSORPTION; CROSS-SECTIONS; ATOMIC OXYGEN; NITRIC-OXIDE; IONIZATION SPECTROSCOPY; PROFILE MEASUREMENTS; STIMULATED-EMISSION; SPECIES DETECTION AB The interaction of an absorption line and a resonant laser is often modeled using a spectral overlap integral. Previous investigators have modified the traditional overlap integral to obtain a dimensionless overlay integral that affords a more practical interpretation. Unique to the derivation of the modified integral is the treatment of the laser-spectral-irradiance profile - its area is normalized to equal the spectral full-width at half-maximum. In this paper, the modified laser spectral irradiance is applied to obtain a dimensionless overlay integral for multi-photon absorption, including the case of two-photon absorption. Close attention is given to the units applied to the calculation of absorption rate coefficients, including those for the laser flux, laser irradiance, interaction cross sections, and distribution functions. The results are tabulated for two cases - frequency expressed in units of wave numbers and frequency expressed in units of Hertz. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Propuls Directorate, Wright Patterson AFB, OH 45433 USA. RP Fiechtner, GJ (reprint author), Innovat Sci Solut Inc, 2766 Indian Ripple Rd, Dayton, OH 45440 USA. NR 75 TC 6 Z9 6 U1 0 U2 7 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 MAR 1 PY 2001 VL 68 IS 5 BP 543 EP 557 DI 10.1016/S0022-4073(00)00044-3 PG 15 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 394YB UT WOS:000166551000006 ER PT J AU Al-qahtani, JM McLean, IW Weiblinger, RP Ediger, MN AF Al-qahtani, JM McLean, IW Weiblinger, RP Ediger, MN TI Preliminary in vitro study of the histological effects of low fluence 193-nm excimer laser irradiation of corneal tissue SO JOURNAL OF REFRACTIVE SURGERY LA English DT Article ID ABLATION; LIGHT; INCISIONS; SURFACE; LENS; NM AB PURPOSE: To determine if moderate numbers of low fluence, 193-nm excimer laser pulses modify or damage the corneal stroma. METHODS: The corneal epithelium of fresh bovine eyes was scraped off and the exposed stroma was irradiated with 200 low fluence laser pulses from an argon fluoride excimer laser. This process was performed on five eyes each at two laser fluences, 10 mJ/cm(2) and 30 mJ/cm(2). The ten irradiated and three control (unirradiated) corneas were sectioned and studied by electron microscopy. The maximum and minimum thickness of the anterior layer of randomly oriented collagen fibers was measured using electron microscopy. RESULTS: The mean maximum thickness of the anterior randomly oriented layer of collagen was 1.23 +/- 0.45 mum in the control corneas, 0.67 +/- 0.32 mum in the corneas irradiated at 10 mJ/cm(2), and 0.10 +/- 0.12 mum in the corneas irradiated at 30 mJ/cm(2). The mean thickness of corneal stroma removed was 0.7 mum at a fluence of 10 mJ/cm(2) and 1.1 mum at a fluence of 30 mJ/cm(2). A thin, electron-dense pseudomembrane was present at both fluences. CONCLUSION: We report removal of bovine corneal stroma at 10 mJ/cm(2)-below the previously reported ablation threshold of 20 mJ/cm(2). C1 US FDA, Ctr Devices & Radiol Hlth, Rockville, MD 20857 USA. King Fahd Hosp Univ, Alkhobar, Saudi Arabia. USAF, Inst Pathol, Dept Ophthalm Pathol, Washington, DC 20330 USA. RP Ediger, MN (reprint author), US FDA, Ctr Devices & Radiol Hlth, 12725 Twinbrook Pkwy,Rm 200,HFZ-134, Rockville, MD 20857 USA. NR 17 TC 1 Z9 1 U1 0 U2 2 PU SLACK INC PI THOROFARE PA 6900 GROVE RD, THOROFARE, NJ 08086 USA SN 1081-597X J9 J REFRACT SURG JI J. Refractive Surg. PD MAR-APR PY 2001 VL 17 IS 2 BP 105 EP 109 PG 5 WC Ophthalmology; Surgery SC Ophthalmology; Surgery GA 413WT UT WOS:000167635100003 PM 11310758 ER PT J AU Griffin, S Lane, SA Hansen, C Cazzolato, B AF Griffin, S Lane, SA Hansen, C Cazzolato, B TI Active structural-acoustic control of a rocket fairing using proof-mass actuators SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article ID VIBRATION; ABSORBERS; SOUND AB The feasibility of using proof-mass actuators to control noise transmission actively into a small rocket fairing, given practical constraints on actuator power and mass, is explored. The modal-interaction approach was used to develop a fully coupled structural-acoustic state-space model that relates the out-of-plane structural modal velocities to the spatially varying pressure response in the cavity, The dynamics of the proof-mass actuators were included in the structural-acoustic model. The modal-interaction approach also allowed the decomposition of the acoustic response into radiation modes, which proved essential for determining the optimal locations for sensors and actuators, Numerical simulations using linear quadratic Gaussian controllers with collocated proof-mass actuators and displacement sensors demonstrated approximately 4.2 dB of attenuation over the 300-Hz bandwidth for the given actuator constraints. However, this was only slightly more than the attenuation provided by the passive effects of the proof-mass actuators, which was approximately 3.5 dB. C1 USAF, Res Lab, Spacecraft Component Technol Branch, Kirtland AFB, NM 87117 USA. Jackson & Tull Engn, Space & Aeronaut Technol Div, Albuquerque, NM 87106 USA. Univ Adelaide, Dept Mech Engn, Adelaide, SA 5001, Australia. RP Griffin, S (reprint author), USAF, Res Lab, Spacecraft Component Technol Branch, Kirtland AFB, NM 87117 USA. RI Cazzolato, Benjamin/A-8330-2008; Hansen, Colin/A-8327-2008; OI Hansen, Colin/0000-0002-1444-4716; Cazzolato, Benjamin/0000-0003-2308-799X NR 17 TC 19 Z9 20 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 MAR-APR PY 2001 VL 38 IS 2 BP 219 EP 225 DI 10.2514/2.3673 PG 7 WC Engineering, Aerospace SC Engineering GA 421VA UT WOS:000168083200013 ER PT J AU Sabol, C Burns, R McLaughlin, CA AF Sabol, C Burns, R McLaughlin, CA TI Satellite formation flying design and evolution SO JOURNAL OF SPACECRAFT AND ROCKETS LA English DT Article; Proceedings Paper CT AAIA 39th Aerospace Sciences Meeting CY JAN 08-11, 2001 CL RENO, NEVADA SP AIAA ID DYNAMO AB Several satellite formation flying designs and their evolution through time are investigated. Satellite formation dying designs are derived from the linearized equations of relative motion under two-body dynamics better known as Hill's equations (Hill, G, W., "Researches in the Lunar Theory," American Journal of Mathematics, Vol. 1, No. 1, 1878, pp. 5-26), 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 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 dying design and outline the effects of realistic dynamics on those designs. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Sabol, C (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. NR 22 TC 157 Z9 181 U1 6 U2 19 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 MAR-APR PY 2001 VL 38 IS 2 BP 270 EP 278 DI 10.2514/2.3681 PG 9 WC Engineering, Aerospace SC Engineering GA 421VA UT WOS:000168083200020 ER PT J AU Steinwolf, A White, RG Wolfe, HF AF Steinwolf, A White, RG Wolfe, HF TI Simulation of jet-noise excitation in an acoustic progressive wave tube facility SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB Acoustic excitation produced by jet-engine effluxes was simulated in a progressive wave tube (APWT) facility with a computer-based control system. The APWT siren is driven by a signal generated numerically in a PC and then converted into analog farm. Characteristics of the acoustic pressure measured by a microphone are analyzed in digital form and compared with those prescribed for simulation. Divergence is compensated by immediate modification of the driving signal and this action is repeated in the form of iterative process until the test specification is attained. Typical power spectral density (PSD) shapes with maxima at low and high frequencies were simulated. A "tailoring" approach has been also achieved when a test specification was determined directly from field measurements for the particular aircraft under consideration. Since acoustic pressure signals of high level differ fi-om the Gaussian random process model, particularly in terms of asymmetric probability density function, a method has been developed to make the driving signal also non-Gaussian by simulating skewness and kurtosis parameters of the APWT acoustic excitation simultaneously with PSD control. Experimental results with Gaussian and non-Gaussian characteristics obtained for various PSD specifications including sharp and narrow peaks are presented in the paper. (C) 2001 Acoustical Society of America. C1 Univ Sheffield, Dept Engn Mech, Sheffield S1 3JD, S Yorkshire, England. Univ Southampton, Dept Aeronaut & Astronaut, Southampton SO17 1BJ, Hants, England. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Steinwolf, A (reprint author), Univ Sheffield, Dept Engn Mech, Sheffield S1 3JD, S Yorkshire, England. NR 16 TC 1 Z9 1 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAR PY 2001 VL 109 IS 3 BP 1043 EP 1052 DI 10.1121/1.1344159 PG 10 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 409DM UT WOS:000167369300017 PM 11303918 ER PT J AU Brungart, DS AF Brungart, DS TI Informational and energetic masking effects in the perception of two simultaneous talkers SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID SPEECH-RECEPTION THRESHOLD; SPATIAL SEPARATION; COCKTAIL PARTY; NORMAL-HEARING; INTELLIGIBILITY; NOISE; IDENTIFICATION; PATTERNS AB Although most recent multitalker research has emphasized the importance of binaural cues, monaural cues can play an equally important role in the perception of multiple simultaneous speech signals. In this experiment, the intelligibility of a target phrase masked by a single competing masker phrase was measured as a function of signal-to-noise ratio (SNR) with same-talker, same-sex, and different-sex target and masker voices. The results indicate that informational masking, rather than energetic masking, dominated performance in this experiment. The amount of masking was highly dependent on the similarity of the target and masker voices: performance was best when different-sex talkers were used and worst when the same talker was used for target and masker. Performance did not, however, improve monotonically with increasing SNR. Intelligibility generally plateaued at SNRs below 0 dB and, in some cases, intensity differences between the target and masking voices produced substantial improvements in performance with decreasing SNR. The results indicate that informational and energetic masking play substantially different roles in the perception of competing speech messages. C1 USAF, Res Lab, Human Effect Directorate, Wright Patterson AFB, OH 45433 USA. RP Brungart, DS (reprint author), USAF, Res Lab, Human Effect Directorate, Wright Patterson AFB, OH 45433 USA. NR 25 TC 317 Z9 330 U1 0 U2 41 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAR PY 2001 VL 109 IS 3 BP 1101 EP 1109 DI 10.1121/1.1345696 PG 9 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 409DM UT WOS:000167369300023 PM 11303924 ER PT J AU Parthasarathy, TA AF Parthasarathy, TA TI Extraction of Weibull parameters of fiber strength from means and standard deviations of failure loads and fiber diameters SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CERAMIC-MATRIX COMPOSITES; ESTIMATORS; VALIDITY AB The errors in using an average fiber diameter to calculate the mean strength (sigma (m)), Weibull reference strength (sigma (0)), and Weibull modulus (m) from failure loads of fibers were examined experimental. Although the use of an average diameter gave very good estimates of sigma (m), the error in the Weibull parameters (sigma (0) and m) was significant, which supported the recent simulation results. Computational approaches to reduce these errors have been considered, and a numerical procedure to extract the Weibull parameters from the means and standard deviations of the load and fiber diameter has been proven feasible, provided the sample population is large. parametric studies hare shown that sample populations of similar to 175 are required to obtain results within an error of 10%. The recommended sample populations for commercial fibers are 75-200, depending on the scatter in the fiber diameter and the acceptable error. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RP Parthasarathy, TA (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLN, Wright Patterson AFB, OH 45433 USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 12 TC 10 Z9 10 U1 1 U2 5 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAR PY 2001 VL 84 IS 3 BP 588 EP 592 PG 5 WC Materials Science, Ceramics SC Materials Science GA 410YN UT WOS:000167468800018 ER PT J AU Suter, BW Hedges, RA AF Suter, BW Hedges, RA TI Understanding fast Hankel transforms SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID NUMERICAL EVALUATION; ALGORITHM AB Recently Ferrari et al. [J. Opt. Soc. Am. A 16, 2581 (1999)] presented an algorithm for the numerical evaluation of the Hankel transform of nth order. We demonstrate that this formulation can be interpreted as an application of the projection slice theorem. (C) 2001 Optical Society of America. C1 USAF, Res Lab, Rome, NY 13441 USA. RP USAF, Res Lab, Rome, NY 13441 USA. NR 15 TC 9 Z9 9 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1084-7529 EI 1520-8532 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD MAR PY 2001 VL 18 IS 3 BP 717 EP 720 DI 10.1364/JOSAA.18.000717 PG 4 WC Optics SC Optics GA 405JK UT WOS:000167156100029 ER PT J AU Staal, MA AF Staal, MA TI The assessment and prevention of suicide for the 21st century: The Air Force's community awareness training model SO MILITARY MEDICINE LA English DT Article ID HOPELESSNESS; IDEATION; BEHAVIOR; SCALE AB Professional practice standards and ethical obligations in the realm of suicide and risk management have been discussed for the last several decades. In the civilian sector, this discussion has taken the form of malpractice case law, the development of numerous assessment tools and practice guidelines for clinicians, and some attempts to describe possible models of prevention. In the Air Force, concern regarding suicide and risk management has evolved into a formalized program of community awareness and education that has been testing the boundaries of suicidal risk detection, assessment, and support facilitation. This article briefly describes this program, its success, and its implications for both active duty and civilian populations. Guidelines for mental health practice standards in risk management and suicide assessment are also discussed. C1 USAF Acad, Dept Behav Sci & Leadership, Colorado Springs, CO 80840 USA. RP Staal, MA (reprint author), USAF Acad, Dept Behav Sci & Leadership, Colorado Springs, CO 80840 USA. NR 37 TC 11 Z9 12 U1 1 U2 2 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD MAR PY 2001 VL 166 IS 3 BP 195 EP 198 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 411ML UT WOS:000167503800001 PM 11263015 ER PT J AU Ornstein, DL Mortara, KL Smith, MB Ririe, DW Shaughnessy, PJ Bickford, DJ Kissack, BL AF Ornstein, DL Mortara, KL Smith, MB Ririe, DW Shaughnessy, PJ Bickford, DJ Kissack, BL TI Treatment of severe thrombocytopenia in alloimmunized, transfusion-refractory patients SO MILITARY MEDICINE LA English DT Article ID INTRAVENOUS GAMMA-GLOBULIN; HLA-IMMUNIZED PATIENTS; ACUTE MYELOID-LEUKEMIA; PLATELET TRANSFUSIONS; IMMUNOGLOBULIN; THERAPY; MANAGEMENT; THRESHOLD AB A significant proportion of patients with hematologic malignancies who are exposed to multiple transfusions will develop alloantibodies to platelet human leukocyte antigens (HLA], resulting in poor responses to subsequent platelet transfusions. Transfusion of HLA-identical platelets is an effective method of platelet support in these patients, but perfectly HLA-matched platelets are often not available. in this paper, me review the recent literature on platelet transfusion support in alloimmunized individuals and illustrate alternative management strategies with cases from our own practice. C1 Wilford Hall USAF Med Ctr, Bone Marrow Transplantat Serv, San Antonio, TX 78236 USA. RP Ornstein, DL (reprint author), Wilford Hall USAF Med Ctr, Bone Marrow Transplantat Serv, 59 MDW,Lackland AFB, San Antonio, TX 78236 USA. NR 22 TC 1 Z9 1 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD MAR PY 2001 VL 166 IS 3 BP 269 EP 274 PG 6 WC Medicine, General & Internal SC General & Internal Medicine GA 411ML UT WOS:000167503800022 PM 11263033 ER PT J AU Saperstein, DS Katz, JS Amato, AA Barohn, RJ AF Saperstein, DS Katz, JS Amato, AA Barohn, RJ TI Clinical spectrum of chronic acquired demyelinating polyneuropathies SO MUSCLE & NERVE LA English DT Review DE chronic inflammatory demyelinating polyneuropathy (CIDP); distal acquired demyelinating symmetric (DADS) neuropathy; Lewis-Sumner syndrome; multifocal acquired demyelinaling sensory and motor (MADSAM) neuropathy; multifocal motor neuropathy (MMN) ID MULTIFOCAL MOTOR NEUROPATHY; PERSISTENT CONDUCTION BLOCK; LEWIS-SUMNER-SYNDROME; INTRAVENOUS IMMUNOGLOBULIN TREATMENT; MYELIN-ASSOCIATED GLYCOPROTEIN; ANTI-MAG ANTIBODIES; RELAPSING AXONAL NEUROPATHY; IGM MONOCLONAL GAMMOPATHY; GUILLAIN-BARRE-SYNDROME; INTERFERON-ALPHA 2A AB A number of presentations of chronic demyelinating polyneuropathy have been identified, each distinguished by its phenotypic pattern. In addition to classic chronic inflammatory demyelinating polyneuropathy (CIDP), which is characterized clinically by symmetric proximal and distal weakness and sensory loss, several regional variants can be recognized: multifocal motor neuropathy (MMN: asymmetric and pure motor), multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy (asymmetric, sensory, and motor), and distal acquired demyelinating symmetric (DADS) neuropathy (symmetric, distal, sensory, and motor). There are also temporal, pathological, and disease-associated variants. This review describes a clinical scheme for approaching the chronic acquired demyelinating polyneuropathies that leads to a rational use of supportive laboratory studies and treatment options. In addition, we propose new diagnostic criteria for CIDP that more accurately reflect current clinical practice. (C) 2001 John Wiley & Sons, Inc. C1 Wilford Hall USAF Med Ctr, Dept Neurol, San Antonio, TX 78236 USA. Stanford Univ, Dept Neurol & Neurosci, Palo Alto, CA 94304 USA. Harvard Univ, Brigham & Womens Hosp, Sch Med, Dept Neurol, Boston, MA 02115 USA. Univ Kansas, Med Ctr, Dept Neurol, Kansas City, KS 66103 USA. RP Saperstein, DS (reprint author), Wilford Hall USAF Med Ctr, Dept Neurol, 2200 Bergquist Dr,Suite 1 MMCN, San Antonio, TX 78236 USA. NR 140 TC 265 Z9 277 U1 2 U2 8 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0148-639X J9 MUSCLE NERVE JI Muscle Nerve PD MAR PY 2001 VL 24 IS 3 BP 311 EP 324 DI 10.1002/1097-4598(200103)24:3<311::AID-MUS1001>3.0.CO;2-A PG 14 WC Clinical Neurology; Neurosciences SC Neurosciences & Neurology GA 404TN UT WOS:000167117100002 PM 11353415 ER PT J AU Leonard, DL Charlton, DG Roberts, HR Hilton, TJ Zionic, A AF Leonard, DL Charlton, DG Roberts, HR Hilton, TJ Zionic, A TI Determination of the minimum irradiance required for adequate polymerization of a hybrid and a microfill composite SO OPERATIVE DENTISTRY LA English DT Article ID CURE; RESINS; DEPTH; INTENSITY; OUTPUT; UNITS AB This in vitro study determines the minimum irradiance values required for adequate polymerization of a microfill and a hybrid resin composite when cured for 40 and 60 seconds, A curing light (Optilux 401) with an 8-mm-diameter tip (SaniCure) was used as the light source, The irradiance output of the light unit, measured with a laser power meter, was varied by altering the input voltage using a variable power supply, Two-mm-thick hardness test specimens were made with a microfill composite (Silux Plus) and a hybrid composite (Z-100) for each combination of exposure time (40, 60 seconds) and irradiance value (100 mW/cm(2) to 700 mW/cm(2) in 25-mW/cm(2) increments), After 24 hours, Knoop hardness (KH) measurements were made for each side of each specimen, means were calculated and a top/bottom KH percentage was determined. A value of at least 80% was used to indicate satisfactory polymerization, A linear regression of irradiance versus KH percentage was performed and the resulting equation used to predict the irradiance value required to produce a IM value of 80% for the test conditions. Results showed that the hybrid composite, Z-100, required 260.1 mW/cm(2) @ 40 seconds or 185.0 mW/cm(2)@ 60 seconds for satisfactory polymerization. The microfill, Silux Plus, required 542.9 mW/cm(2) @ 40 seconds or 449.0 mW/cm(2) @ 60 seconds. These findings indicate that previously stated minimum irradiance values may be insufficient for adequate polymerization of microfill resin composites. C1 USAF, Dent Invest Serv, USAFSAM, Great Lakes, IL 60088 USA. RP Leonard, DL (reprint author), USAF, Dent Invest Serv, USAFSAM, Detachment 1,310C B St,Bldg 1H, Great Lakes, IL 60088 USA. NR 19 TC 13 Z9 15 U1 0 U2 0 PU OPERATIVE DENTISTRY INC PI INDIANAPOLIS PA INDIANA UNIV SCHOOL DENTISTRY, ROOM S411, 1121 WEST MICHIGAN ST, INDIANAPOLIS, IN 46202-5186 USA SN 0361-7734 J9 OPER DENT JI Oper. Dent. PD MAR-APR PY 2001 VL 26 IS 2 BP 176 EP 180 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 408JW UT WOS:000167323900012 ER PT J AU Vydyanath, HR Nathan, V AF Vydyanath, HR Nathan, V TI Materials and process issues in the fabrication of high performance VLWIR HgCdTe infrared detectors SO OPTO-ELECTRONICS REVIEW LA English DT Article DE HgCdTe photodiodes; R(o)A product; heterostructures; lateral collection ID (HG,CD)TE; MODE AB Issues relating to fabrication of VLWIR HgCdTe detectors with high performance and uniformity are reviewed. The primary mechanism operative in the activation of p type dopants in HgCdTe is discussed along with implications for fabrication of high performance detectors. Origin of native defect related deep centres in limiting the minority carrier lifetime is explored. C1 Avyd Devices Inc, Costa Mesa, CA 92626 USA. USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Vydyanath, HR (reprint author), Avyd Devices Inc, 2925 Coll Ave,Unit A-1, Costa Mesa, CA 92626 USA. NR 12 TC 7 Z9 7 U1 0 U2 0 PU ASSOC POLISH ELECTRICAL ENGINEERS (S E P) PI WARSAW PA 2 KALISKIEGO STR, 00-908 WARSAW, POLAND SN 1230-3402 J9 OPTO-ELECTRON REV JI Opto-Electron. Rev. PD MAR PY 2001 VL 9 IS 1 BP 1 EP 5 PG 5 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 422XD UT WOS:000168143800001 ER PT J AU Harville, DL AF Harville, DL TI Motivation management: Fueling performance by discovering what people believe about themselves and their organizations. SO PERSONNEL PSYCHOLOGY LA English DT Book Review C1 USAF, Res Lab, Brooks AFB, TX USA. RP Harville, DL (reprint author), USAF, Res Lab, Brooks AFB, TX USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU PERSONNEL PSYCHOLOGY INC PI BOWLING GREEN PA 745 HASKINS ROAD, SUITE A, BOWLING GREEN, OH 43402 USA SN 0031-5826 J9 PERS PSYCHOL JI Pers. Psychol. PD SPR PY 2001 VL 54 IS 1 BP 216 EP 219 PG 4 WC Psychology, Applied; Management SC Psychology; Business & Economics GA 411NH UT WOS:000167505800016 ER PT J AU Woodward, C Asta, M Kresse, G Hafner, J AF Woodward, C Asta, M Kresse, G Hafner, J TI Density of constitutional and thermal point defects in L1(2) Al3Sc SO PHYSICAL REVIEW B LA English DT Article ID AB-INITIO; TI-AL; ATOMISTIC SIMULATION; ELECTRONIC-STRUCTURE; MOLECULAR-DYNAMICS; ORDERED ALLOYS; SC ALLOYS; TRANSITION; DIFFUSION; PSEUDOPOTENTIALS AB The energy of constitutional and thermal point defects in Ll(2) Al3Sc are calculated within a first principles, local density functional theory framework. Relaxed structures and energies for vacancies and antisites are calculated using a plane-wave pseudopotential method. The resulting energies are used within a dilute-solution thermodynamic formalism to estimate the equilibrium point defect densities as functions of temperature and alloy composition. The first-principles-based thermodynamic calculations predict that Al3Sc forms antisite constitutional defects fur both Al- and Sc-rich alloys. Also, the density of thermal vacancies is found to be very sensitive to the underlying stoichiometry. At 1000 K the Sc-sublattice vacancy concentration increases by ten orders of magnitude as the alloy goes from Sc to Al rich. At this temperature, the density of Sc-sublattice vacancies is predicted to be comparable to the concentration of Al antisite defects for Al-rich alloys. C1 USAF, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Univ Vienna, Inst Mat Phys, Vienna, Austria. RP Woodward, C (reprint author), Universal Energy Syst Inc, Mat & Proc Div, 4401 Dayton Xenia Rd, Dayton, OH 45432 USA. NR 42 TC 38 Z9 40 U1 0 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 1 PY 2001 VL 63 IS 9 AR 094103 DI 10.1103/PhysRevB.63.094103 PG 6 WC Physics, Condensed Matter SC Physics GA 408DV UT WOS:000167312000026 ER PT J AU Haddock, CK Vander Weg, M DeBon, M Klesges, RC Talcott, GW Lando, H Peterson, A AF Haddock, CK Vander Weg, M DeBon, M Klesges, RC Talcott, GW Lando, H Peterson, A TI Evidence that smokeless tobacco use is a gateway for smoking initiation in young adult males SO PREVENTIVE MEDICINE LA English DT Article DE smokeless tobacco; smoking initiation; gateway drug; young adults; military recruits ID NICOTINE ADDICTION; PATTERNS; STATES AB Background. This study was designed to test the hypothesis that smokeless tobacco (SLT) serves as a gateway drug for smoking among young adult males. Methods. A cohort (n = 7,865) of U.S. Air Force recruits who claimed to have never smoked cigarettes was followed prospectively for 1 year. The participants were male, 32.9% were ethnic minorities, and their average age was 19.84 years (SD = 2.29). Among recruits entering basic military training, 403 (5.1%) reported current SLT use and 198 (2.5%) reported a past history of SLT use. Results. At the 1-year follow-up current SLT users were 233% more likely to have initiated smoking than nonusers (odds ratio = 2.33, 95% CI = 1.84-2.94). Similarly, recruits who reported past SLT use were 227% more likely to begin smoking than participants who had never used SLT (odds ratio = 2.27, 95% CI = 1.64-3.15). SLT use remained a potent predictor of smoking initiation in a multivariate logistic model that included demographic factors and other risk factors for initiation. Conclusions. SLT use appears to be an important predictor of smoking initiation among young adult males. This study suggests that smoking prevention and cessation programs should also include strategies related to SLT use. (C) 2001 American Health Foundation and Academic Press. C1 Univ Missouri, Hlth Res Grp, Kansas City, MO 64110 USA. St Lukes Hosp, Mid Amer Heart Inst, Kansas City, MO 64110 USA. Univ Memphis, Memphis, TN 38119 USA. Off Air Force Surg Gen, Bolling AFB, MD 20332 USA. Univ Minnesota, Minneapolis, MN 55454 USA. Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. RP Haddock, CK (reprint author), Univ Missouri, Hlth Res Grp, 4825 Troost,Suite 124, Kansas City, MO 64110 USA. OI Vander Weg, Mark/0000-0003-3631-0812 FU NHLBI NIH HHS [HL53478] NR 26 TC 91 Z9 92 U1 0 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0091-7435 J9 PREV MED JI Prev. Med. PD MAR PY 2001 VL 32 IS 3 BP 262 EP 267 DI 10.1006/pmed.2000.0802 PG 6 WC Public, Environmental & Occupational Health; Medicine, General & Internal SC Public, Environmental & Occupational Health; General & Internal Medicine GA 409VQ UT WOS:000167406700010 PM 11277684 ER PT J AU Bennett, JM AF Bennett, JM TI Ignition of combustible fluids by heated surfaces SO PROCESS SAFETY PROGRESS LA English DT Article AB Industrial machinery fires are commonly caused bq,flammable operating fluids leaking onto hot machinery surfaces. This paper discusses doctoral research currently underway, to identify the dominant fundamental mechanisms controlling the overall ignition process of combustible liquid stream;fed pools impinging on heated surfaces. Experiments are now underway to characterize these processes, via modeling and the use of dimensional analysis, to be able to predict the minimum surface ignition temperature for a given set of lu id and surface properties, more accurately define safe operating boundaries of equipment to mitigate fire events, and suggest optimal designs to widen the safe operating envelope. As a result of recent analyses, a surface modification technique has been proposed to use a pattern of micro-cavities, sired to prevent fluid seepage, on the exterior of the heated surface to reduce the heat transfer from surface to liquid (due to reduced direct contact), and inhibit the formation of superheated vapor films. This behavior could increase the temperatures necessary for ignition, permitting! a wider range of safe operating conditions. C1 USAF, Wright Patterson AFB, OH 45433 USA. RP Bennett, JM (reprint author), USAF, 46 OG-OGM-OL-AC,2700 D St,Bldg 22-B, Wright Patterson AFB, OH 45433 USA. NR 10 TC 8 Z9 10 U1 0 U2 0 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 3 PARK AVE, NEW YORK, NY 10016-5901 USA SN 1066-8527 J9 PROCESS SAF PROG JI Process Saf. Prog. PD MAR PY 2001 VL 20 IS 1 BP 29 EP 36 PG 8 WC Engineering, Chemical SC Engineering GA 419EB UT WOS:000167935400008 ER PT J AU Bourgeois, JA Chozinski, JP Walker, DM AF Bourgeois, JA Chozinski, JP Walker, DM TI Psychiatric residents as CME presenters SO PSYCHIATRIC SERVICES LA English DT Letter C1 Univ Calif Davis, Dept Psychiat, Davis, CA 95616 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Bourgeois, JA (reprint author), Univ Calif Davis, Dept Psychiat, Davis, CA 95616 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER PSYCHIATRIC PRESS, INC PI WASHINGTON PA 1400 K ST, N W, STE 1101, WASHINGTON, DC 20005 USA SN 1075-2730 J9 PSYCHIATR SERV JI Psychiatr. Serv. PD MAR PY 2001 VL 52 IS 3 BP 389 EP 389 DI 10.1176/appi.ps.52.3.389 PG 1 WC Health Policy & Services; Public, Environmental & Occupational Health; Psychiatry SC Health Care Sciences & Services; Public, Environmental & Occupational Health; Psychiatry GA 408MG UT WOS:000167329500028 PM 11239118 ER PT J AU Kofford, KR Wakefield, CW Murchison, DF AF Kofford, KR Wakefield, CW Murchison, DF TI Aluminum oxide air abrasion particles: A bacteriologic and SEM study SO QUINTESSENCE INTERNATIONAL LA English DT Article DE air abrasion; aluminum oxide powder; mean particle size; microbial contamination; microdentistry ID MICROBIAL-CONTAMINATION; ENAMEL; DENTIN; BRANDS AB Objective: The objective is to determine if aerobic and anaerobic sampling yields Viable biologic contaminants in the aluminum oxide air abrasion powder as delivered by the manufacturer and to determine mean particle size for comparison with the published size from manufacturers and the range of sizes in the powders. Method and materials: Samples from 15 unopened aluminum oxide powder containers from 9 different manufacturers were plated on aerobic and anaerobic culture media. The cultures were incubated at 35 degreesC and observed at 24-hour intervals. Samples of each of the 15 groups were subjected to scanning electron microscope (SEM) examination. Photomicrographs were obtained and a range and mean particle size determined. Results: Aerobic and anaerobic cultures demonstrated no growth in any of the samples. Mean particle size determined by SEM for 25- to 27.5-mum particles ranged from 27.3 mum to 32.0 mum with standard deviations from 1.06 mum to 7.70 mum. Mean particle size for 50 mum particles ranged from 51.6 mum to 59.7 mum with standard deviations of 5.48 mum to 14.80 mum. Conclusion: Aluminum oxide powders as delivered by manufacturers appeared to be free from viable microorganisms. The powder mean particle sizes approximate the labeled sizes closely enough such that they should perform properly in air abrasion tooth preparation. C1 Texas A&M Univ, Hlth Sci Ctr, Adv Educ Gen Dent Program, Baylor Coll Dent, Dallas, TX 75246 USA. USA, 2 Year Program, Ft Hood, TX USA. Wilford Hall USAF Med Ctr, Dept Gen Dent, San Antonio, TX 78236 USA. RP Wakefield, CW (reprint author), Texas A&M Univ, Hlth Sci Ctr, Adv Educ Gen Dent Program, Baylor Coll Dent, Dallas, TX 75246 USA. NR 14 TC 0 Z9 1 U1 0 U2 0 PU QUINTESSENCE PUBL CO INC PI CAROL STREAM PA 551 NORTH KIMBERLY DR, CAROL STREAM, IL 60188-1881 USA SN 0033-6572 J9 QUINTESSENCE INT JI Quintessence Int. PD MAR PY 2001 VL 32 IS 3 BP 243 EP 248 PG 6 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 413DY UT WOS:000167595700011 PM 12066666 ER PT J AU Sojka, JJ Thompson, DC Schunk, RW Bullett, TW Makela, JJ AF Sojka, JJ Thompson, DC Schunk, RW Bullett, TW Makela, JJ TI Assimilation ionosphere model: Development and testing with combined ionospheric campaign caribbean measurements SO RADIO SCIENCE LA English DT Article; Proceedings Paper CT Ionospheric Effect Symposium (IES 99) CY MAY 04-06, 1999 CL ALEXANDRIA, VIRGINIA SP Air Force Off Sci Res, Fed Aviat Adm, Off Naval Res, Air Force Res Lab, Air Force Space & Missile Syst Ctr, Fed Communicat Commiss, Natl Ocean & Atmospher Adm, Naval Res Lab, Univ Massachusetts Lowell, NW Res Associates, USA, Communicat Electr Command, Innovat Solut Int Inc ID MERIDIONAL WINDS; NEUTRAL WINDS; HEIGHT AB Assimilation Ionosphere Model (AIM) is a physics-based, global, ionospheric specification model that is currently under development. It assimilates a diverse set of real-time (or near-real-time) measurements, such as ionograms, GPS slant total electron content (TEC), and in situ plasma measurements. This study focuses on a middle latitude ionosonde assimilation capability in both local and regional forms. The models described are capable of using the f(0)F(2) and h(m)F(2) from ionograms to generate either a local or a regional distribution of the induced plasma drift. This induced drift is usually caused by the meridional neutral wind. Results from a local model (AIM1.03L) and a regional model (AIM1.03R) are presented and compared with the international reference ionosphere (IRI) climatological predictions as well as GPS slant TEC measurements. Results from year-long studies during solar maximum show that the accuracy of the AIM1.03L model is about a factor of 2 better than that of IRI. An initial month-long regional study is also presented, and the results are almost as good. A study is also carried out using observations taken during the Combined Ionospheric Campaign (CIC) held in November, 1997, in the Caribbean. The digisonde located at Ramey Solar Observatory is used to drive the AIM1.03L model, and the predicted GPS slant TECs are compared to those observed by a GPS receiver located at St. Croix. This study confirms that this first step in preparing a weather-sensitive ionospheric representation is superior to a climatological representation. This sets the stage for the development of full assimilation of GPS TEC, in situ density measurements, etc., and it is anticipated that the AIM1.03LR ionospheric representation will provide an accurate ionospheric specification. C1 Space Environm Corp, Logan, UT 84321 USA. USAF, Res Lab, Battlespace Environm Div, Hanscom AFB, MA 01731 USA. Cornell Univ, Dept Elect & Comp Engn, Ithaca, NY 14853 USA. RP Sojka, JJ (reprint author), Space Environm Corp, 399 North Main,Suite 325, Logan, UT 84321 USA. NR 16 TC 19 Z9 24 U1 0 U2 2 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 MAR-APR PY 2001 VL 36 IS 2 BP 247 EP 259 DI 10.1029/1999RS002411 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 415VR UT WOS:000167744700008 ER PT J AU Klesges, RC Haddock, CK Chang, CF Talcott, GW Lando, HA AF Klesges, RC Haddock, CK Chang, CF Talcott, GW Lando, HA TI The association of smoking and the cost of military training SO TOBACCO CONTROL LA English DT Article DE military; smoking ban; training costs ID CESSATION; TOBACCO AB Objective-To determine if premature discharge from the US Air Force was associated with the smoking status of recruits. Design and setting-A total of 29 044 US Air Force personnel recruited from August 1995 to August 1996 were administered baseline behavioural risk assessment surveys during basic military training. They were tracked over a 12 month period to determine those who were prematurely discharged. Main outcome measures-Excess training costs as a result of premature discharge. Results- In this 12 month period, 14.0% of those entering the US Air Force were discharged at a one year follow up. In both univariate and multivariate models, the best single predictor of early discharge was smoking status. Overall, 11.8% of non-smokers versus 19.4% of smokers were prematurely discharged (relative risk 1.795). Conclusions-Using US Department of Defense data on the cost of military training, recruits who smoke in the US Air Force are associated with $18 million per year in excess training costs. Applied to all service branches, smoking status, which represents a constellation of underlying behaviours and attitudes that can contribute to early discharge, is associated with over $130 million per year in excess training costs. C1 Univ Memphis, Ctr Community Hlth, Memphis, TN 38119 USA. Univ Missouri, Kansas City, MO 64110 USA. USAF, Surg Gen Off, Washington, DC 20330 USA. Univ Minnesota, Minneapolis, MN 55455 USA. RP Klesges, RC (reprint author), Univ Memphis, Ctr Community Hlth, Suite 675,5350 Poplar Ave, Memphis, TN 38119 USA. FU NHLBI NIH HHS [HL-53478] NR 19 TC 43 Z9 43 U1 0 U2 1 PU BRITISH MED JOURNAL PUBL GROUP PI LONDON PA BRITISH MED ASSOC HOUSE, TAVISTOCK SQUARE, LONDON WC1H 9JR, ENGLAND SN 0964-4563 J9 TOB CONTROL JI Tob. Control PD MAR PY 2001 VL 10 IS 1 BP 43 EP 47 DI 10.1136/tc.10.1.43 PG 5 WC Public, Environmental & Occupational Health SC Public, Environmental & Occupational Health GA 409HP UT WOS:000167378500016 PM 11226360 ER PT J AU Diffin, DC Kandarpa, K AF Diffin, DC Kandarpa, K TI Percutaneous recanalization of peripheral arterial occlusions SO WORLD JOURNAL OF SURGERY LA English DT Article ID LOWER-LIMB ISCHEMIA; TISSUE-PLASMINOGEN-ACTIVATOR; LOWER-EXTREMITY ISCHEMIA; LOW-DOSE STREPTOKINASE; THROMBOLYTIC THERAPY; RANDOMIZED TRIAL; ASPIRATION THROMBOEMBOLECTOMY; INTRAARTERIAL THROMBOLYSIS; EMBOLIC OCCLUSIONS; INITIAL TREATMENT AB The aim of this paper is to summarize the current status of percutaneous methods for recanalizing peripheral arterial occlusions. Emphasis is placed on the role of peripheral intraarterial thrombolysis (PIAT) in the treatment of acute lower limb ischemia. Results of three prospective, randomized trials comparing PIAT with surgical revascularization are analyzed in the context of the existing, largely retrospective literature. The technique and recommendations for the application of PUT are reviewed. Percutaneous aspiration thromboembolectomy, a technique that may be used alone or in conjunction with PIAT, is described in detail. We conclude with a brief description of various percutaneous mechanical thrombectomy devices, which may potentially see application in peripheral arterial occlusions. C1 Wilford Hall USAF Med Ctr, Dept Radiol, Div Vasc & Intervent Radiol, MTDS MTRD 759, Lackland AFB, TX 78236 USA. Cornell Univ, Sch Med, New York Presbyterian Hosp, Dept Cardiovasc & Intervent Radiol, New York, NY 10021 USA. RP Diffin, DC (reprint author), Westerly Radiol Associates, 81 Beach St, Westerly, RI 02891 USA. NR 40 TC 3 Z9 4 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0364-2313 J9 WORLD J SURG JI World J.Surg. PD MAR PY 2001 VL 25 IS 3 BP 312 EP 318 PG 7 WC Surgery SC Surgery GA 426PP UT WOS:000168357800012 PM 11343183 ER PT J AU Schneider, S Vij, A Sheehy, JA Tham, FS Schroer, T Christe, KO AF Schneider, S Vij, A Sheehy, JA Tham, FS Schroer, T Christe, KO TI In pursuit of the PO2+ cation. The reaction of KPO2F2 and SbF5 leads to an eight-membered antimony-oxygen-phosphorus-bridged ring SO ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE LA English DT Article DE phosphorus; vibrational spectroscopy; NMR spectroscopy; crystal structure; ab initio calculations ID GAUSSIAN-BASIS SETS; TRENDS AB The reaction of KPO2F2 with the strong Lewis acid SbF5 was studied as a potential pathway to the unknown PO2+ cation. The resulting product has the desired PO2SbF6 composition but consists of an eight-membered, antimony-oxygen-phosphorus-bridged ring that was characterized by vibrational and NMR spectroscopy, ab initio methods, and a Institute. University of Southern California. University Park single crystal x-ray diffraction study. The preferred formation of the ring and its mechanism are discussed. C1 Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. USAF, Res Lab, Edwards, CA USA. Univ Calif Riverside, Riverside, CA 92521 USA. RP Christe, KO (reprint author), Univ So Calif, Loker Hydrocarbon Res Inst, Univ Pk, Los Angeles, CA 90089 USA. RI Vij, Ashwani/A-2836-2012; Christe, Karl/O-4885-2014 OI Vij, Ashwani/0000-0003-1144-4080; Christe, Karl/0000-0003-0661-5519 NR 25 TC 3 Z9 3 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0044-2313 J9 Z ANORG ALLG CHEM JI Z. Anorg. Allg. Chem. PD MAR PY 2001 VL 627 IS 4 BP 631 EP 637 DI 10.1002/1521-3749(200104)627:4<631::AID-ZAAC631>3.0.CO;2-C PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 420TE UT WOS:000168020700010 ER PT J AU Poggie, J Smits, AJ AF Poggie, J Smits, AJ TI Shock unsteadiness in a reattaching shear layer SO JOURNAL OF FLUID MECHANICS LA English DT Article ID TURBULENT BOUNDARY-LAYER; WALL-PRESSURE-FLUCTUATIONS; ORGANIZED STRUCTURES; FLOWS; PHYSICS AB The origin of shock unsteadiness in a Mach 2.9 turbulent reattaching shear layer was investigated experimentally using temporally resolved flow visualization and measurements of wall pressure fluctuations. In this how, the separation point of a turbulent boundary layer is essentially fixed at a backward-facing step, and the reattachment point is free to move along a ramp. In order to examine the influence of disturbances originating in the incoming shear layer, artificial disturbances were introduced into the flow through steady air injection in the vicinity of separation. The effect on the reattachment shock system was dramatic: the intensity of the pressure fluctuations and the amplitude of the shock motion increased substantially, and power spectra of the pressure fluctuations showed a distinct shift to lower frequency. The spectra collapsed, onto a common curve in non-dimensional coordinates based on a length scale derived from two-point cross-correlations of the flow visualization data and a convection velocity derived from cross-correlations of the pressure measurements. The data were compared to a theory developed by Plotkin (1975), which is based on perturbation of a shock by random fluctuations in the incoming turbulent flow. Plotkin's model mimics the manner in which relatively broad-band perturbations in the incoming turbulent flow lead to relatively low-frequency motion of the separation bubble and its associated shock system. It is an excellent fit to separation shock motion, such as that generated in a blunt fin flow (briefly illustrated here). In the present shear layer flow, this low-frequency motion was detectable in the spectra near reattachment, but contained considerably less energy relative to the shock motions caused by direct perturbations by the incoming turbulent structures. These results indicate that the shock motion in the reattaching shear layer is primarily caused by organized structures in the incoming turbulent how. C1 USAF, Res Lab, AFRL, VAAC, Wright Patterson AFB, OH 45433 USA. Princeton Univ, Dept Mech & Aerosp Engn, Princeton, NJ 08544 USA. RP Poggie, J (reprint author), USAF, Res Lab, AFRL, VAAC, 2210 8th St, Wright Patterson AFB, OH 45433 USA. RI Smits, Alexander/B-4083-2016 OI Smits, Alexander/0000-0002-3883-8648 NR 44 TC 14 Z9 14 U1 0 U2 5 PU CAMBRIDGE UNIV PRESS PI PORT CHESTER PA 110 MIDLAND AVE, PORT CHESTER, NY 10573-4930 USA SN 0022-1120 J9 J FLUID MECH JI J. Fluid Mech. PD FEB 25 PY 2001 VL 429 BP 155 EP 185 DI 10.1017/S002211200000269X PG 31 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 411KW UT WOS:000167500100006 ER PT J AU Shen, YZ Swiatkiewicz, J Jakubczyk, D Xu, FM Prasad, PN Vaia, RA Reinhardt, BA AF Shen, YZ Swiatkiewicz, J Jakubczyk, D Xu, FM Prasad, PN Vaia, RA Reinhardt, BA TI High-density optical data storage with one-photon and two-photon near-field fluorescence microscopy SO APPLIED OPTICS LA English DT Article ID FORCE AB A spatially localized photochemical reaction induced by near-field femtosecond laser pulses is demonstrated on a nanometer scale and used for high-density optical data storage. Recorded domains down to 120 and 70 nm are obtained with one-photon and two-photon excitation, respectively. It is shown that the local-field confinement that is due to the quadratic dependence of two-photon excitation on light intensity has the potential to increase the near-field optical storage density. (C) 2001 Optical Society of America. OCIS codes: 210.0210, 350.3450, 180.2520. C1 SUNY Buffalo, Dept Chem, Photon Res Lab, Buffalo, NY 14260 USA. SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA. USAF, Res Lab, Mat Directorate, Polymer Branch, Wright Patterson AFB, OH 45433 USA. RP Shen, YZ (reprint author), SUNY Buffalo, Dept Chem, Photon Res Lab, Buffalo, NY 14260 USA. EM ys5@acsu.buffalo.edu RI Jakubczyk, Daniel/K-8932-2016 OI Jakubczyk, Daniel/0000-0002-2144-3228 NR 13 TC 23 Z9 24 U1 0 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD FEB 20 PY 2001 VL 40 IS 6 BP 938 EP 940 DI 10.1364/AO.40.000938 PG 3 WC Optics SC Optics GA 400ZA UT WOS:000166901500026 PM 18357076 ER PT J AU Miller, TM Van Doren, JM Morris, RA Viggiano, AA AF Miller, TM Van Doren, JM Morris, RA Viggiano, AA TI Calculation of the anion and neutral thermochemistry of c-C5F6Cl2 and c-C6F8Cl2 SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE density functional theory; 1,2-dichlorohexafluorocyclopentene; 1,2-dichlorooctafluorocyclohexene; negative ions; electron attachment; electron affinity ID ELECTRON-ATTACHMENT; MOLECULES; SF6 AB Density functional calculations have been carried out to determine the energetics related to nondissociative and dissociative electron attachment to c-C5F6Cl2 (1,2-dichlorohexafluorocyclopentene) and c-C6F8Cl2 (1,2-dichlorooctafluorocyclohexene). Becke's three-parameter functional B3PW91 was used with the 6-311+G(3df) basis set to determine total energies of the parent neutrals and anions, and Of dissociation fragments, at 0 and 298 K. From these total energies, electron affinities, bond enthalpies, and electron attachment reaction enthalpies were determined. The electron affinities of c-C5F6Cl2 and c-C6FCl2 were found to be 1.17 and 1.46 eV, respectively. Implications for the experimental results are discussed, notably that dissociative electron attachment to c-C5F6Cl2 (and probably to c-C5F6Cl2 as well) is endothermic, (Int J Mass Spectrom 205 (2001) 271-276) (C) 2001 Elsevier Science B.V. C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. Coll Holy Cross, Dept Chem, Worcester, MA 01610 USA. RP Miller, TM (reprint author), USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. NR 18 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD FEB 20 PY 2001 VL 205 IS 1-3 SI SI BP 271 EP 276 DI 10.1016/S1387-3806(00)00295-5 PG 6 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 402YQ UT WOS:000167016100026 ER PT J AU Dewan, EM Picard, RH AF Dewan, EM Picard, RH TI On the origin of mesospheric bores SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GRAVITY-WAVE BREAKING; TEMPERATURE-INVERSION; ATMOSPHERE; REGION; LIDAR; LAYER AB A dramatic front of airglow radiance and wave structure reported by Taylor et al. [1995] was attributed, in a previous paper of ours [Dewan and Picard, 1998], to a manifestation of an internal undular bore in the mesosphere. In the current paper we address the question of what physical process could be responsible for generating such a bore at that altitude. While it is relatively easy to find sources of internal tropospheric bores, including the dramatic "morning glory," the same cannot be said for mesospheric bores. It will be argued here that a likely candidate for the generator of such bores is the interaction of gravity waves with the mean flow at a critical layer. This interaction could take place within an already existing inversion layer, the latter playing the role of the "channel" in which the bore propagates. As Huang et al. [1998] have shown, a similar wave/critical-level interaction may be responsible for the inversion layer in question. Hence we are proposing that the physical process producing the channel is the same as the one responsible for subsequently generating the bore. C1 USAF, Res Lab, VSBM, Hanscom AFB, MA 01731 USA. RP Dewan, EM (reprint author), USAF, Res Lab, VSBM, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 30 TC 43 Z9 43 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD FEB 16 PY 2001 VL 106 IS D3 BP 2921 EP 2927 DI 10.1029/2000JD900697 PG 7 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 401TW UT WOS:000166945200001 ER PT J AU Shenberger, JS Dixon, PS Choate, J Helal, K Shew, RL Barth, W AF Shenberger, JS Dixon, PS Choate, J Helal, K Shew, RL Barth, W TI Pregnancy and labor increase the capacity of human myometrial cells to secrete parathyroid hormone-related protein SO LIFE SCIENCES LA English DT Article DE parathyroid hormone-related protein; uterus; smooth muscle; pregnancy ID TRANSFORMING GROWTH-FACTOR-BETA-1 TGF-BETA-1; MESSENGER-RIBONUCLEIC-ACID; SMOOTH-MUSCLE CELLS; GROWTH-FACTOR-BETA; RAT UTERUS; IN-VITRO; GENE-EXPRESSION; PEPTIDE GENE; RNA; RECEPTOR AB Parathyroid hormone-related protein (PTHrP), a oncofetal gene product possessing smooth muscle relaxant properties, has been found in rat and human uterine smooth muscle cells (USMC) where it is postulated to regulate myometrial tone and/or blood flow. Studies investigating the gestational regulation of PTHrP in human USMC have not been performed. This study was conducted to determine if pregnancy alters the capacity of USMC to secrete or respond to PTHrP. USMC cultures were established from 8 hysterectomy specimens (H) and 7 non-laboring (NP) and 5 laboring term pregnant uterine biopsies (LP). PTHrP secretion was measured at baseline and in response to TGF-beta, using a immunoradiometric assay. The USMC response to PTHrP was assessed by incubating cultures with human (1-34)PTHrP and measuring cellular cAMP by radioimmunoassay. We found that cultures from the groups did not differ with respect to basal PTHrP secretion. TGF-beta (1), on the other hand, produced dose-dependent increases in secreted PTHrP in each group such that LP>NP>H at 12 hrs and LP>NP and H 24 hrs. Maximal responses were found at 24 hrs in cells treated with 10 ng/ml TGF-beta (1) (LP: 2034+/-366 vs NP: 1485+/-427; H: 1250+/-202 fmol/mg). Incubation of cultures with PTHrP produced dose-dependent increases in cAMP production, with 10(-7)M increasing levels by 64%. Neither pregnancy nor labor significantly affected the cAMP response. These findings indicate that the human myometrium has the capacity to increase PTHrP secretion during pregnancy and labor through a TGF-beta -dependent pathway. Such findings are consistent with a role of PTHrP in enhancing uterine blood flow. rights reserved. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Univ Kentucky, Dept Pediat, Lexington, KY 40536 USA. Wilford Hall USAF Med Ctr, Dept Obstet & Gynecol, Lackland AFB, TX 78236 USA. Indiana Univ, Med Ctr, Dept Anat & Cell Biol, Indianapolis, IN 46202 USA. RP Shenberger, JS (reprint author), Univ Kentucky, Dept Pediat Neonatol, Chandler Med Ctr, MS-473,800 Rose St, Lexington, KY 40536 USA. NR 31 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0024-3205 J9 LIFE SCI JI Life Sci. PD FEB 16 PY 2001 VL 68 IS 13 BP 1557 EP 1566 DI 10.1016/S0024-3205(01)00949-3 PG 10 WC Medicine, Research & Experimental; Pharmacology & Pharmacy SC Research & Experimental Medicine; Pharmacology & Pharmacy GA 403XB UT WOS:000167067500011 PM 11253172 ER PT J AU Ma, HZ O'Loughlin, EJ Burris, DR AF Ma, HZ O'Loughlin, EJ Burris, DR TI Factors affecting humic-nickel complex mediated seduction of trichloroethene in homogeneous aqueous solution SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID REDUCTIVE DECHLORINATION; CARBON-TETRACHLORIDE; ORGANIC-MATTER; IRON PORPHYRIN; ION-BINDING; SUBSTANCES; DEHALOGENATION; KINETICS; ACID; METHANES AB The kinetics of trichloroethene (TCE) reductive dechlorination mediated by humic-Ni complexes in homogeneous aqueous solution using titanium(III) citrate as the bulk reductant was examined under various environmental conditions (e.g., pH and ionic compositions). Using Ca2+ Zn2+, and Hg2+ ions to vary Aldrich humic acid (HA)-Ni complex concentrations, pseudo-first-order rate constants for TCE reduction were observed to be proportional to HA-NI levels (as calculated by speciation modeling), confirming HA-Ni complexes as the probable active mediator species. TCE reduction by HA-NI was observed to be strongly pH dependent and could be due to both the variations of HA-Ni concentration and E-h With pH. Evidence is presented which suggests that quinone moieties may not be crucial for the humic-Ni mediated reduction of TCE. A variety of natural soil and aqueous humic material and Ni systems were examined, and some showed reactivity toward TCE. Humic-metal complexes may be important electron-transfer mediators in natural systems. C1 USAF, Res Lab, MLQL, Tyndall AFB, FL 32403 USA. RP Burris, DR (reprint author), USAF, Res Lab, MLQL, 139 Barnes Dr,Suite 2, Tyndall AFB, FL 32403 USA. RI O'Loughlin, Edward/C-9565-2013 OI O'Loughlin, Edward/0000-0003-1607-9529 NR 44 TC 16 Z9 18 U1 1 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD FEB 15 PY 2001 VL 35 IS 4 BP 717 EP 724 DI 10.1021/es001314p PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 402MB UT WOS:000166990800012 PM 11349283 ER PT J AU Kalasinsky, KS Bosy, TZ Schmunk, GA Reiber, G Anthony, RM Furukawa, Y Guttman, M Kish, SJ AF Kalasinsky, KS Bosy, TZ Schmunk, GA Reiber, G Anthony, RM Furukawa, Y Guttman, M Kish, SJ TI Regional distribution of methamphetamine in autopsied brain of chronic human methamphetamine users SO FORENSIC SCIENCE INTERNATIONAL LA English DT Article DE methamphetamine; amphetamine; dopamine; dopamine transporter; caudate; putamen; brain ID POSITRON-EMISSION-TOMOGRAPHY; DOPAMINE; REDISTRIBUTION; PET AB We measured levels of methamphetamine and those of its metabolite amphetamine in 15 autopsied brain regions of 14 human methamphetamine users. Only slight regional differences were observed in drug concentrations among the brain areas. Although, some redistribution of the drugs probably occurred postmortem, these data suggest that methamphetamine might not be preferentially retained in dopamine-rich brain areas but is heterogenously distributed in brain of chronic human users of the drug. The possible pharmacological actions of methamphetamine in both dopamine-rich and poor brain areas of chronic drug users need to be considered. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved. C1 Ctr Addict & Mental Hlth, Human Neurochem Pathol Lab, Clarke Div, Toronto, ON M5T 1R8, Canada. USAF, Inst Pathol, Div Forens Toxicol, Off AF Med Examiner, Washington, DC USA. Stanford Univ, Palo Alto, CA 94304 USA. No Calif Forens Pathol, Sacramento, CA USA. RP Kish, SJ (reprint author), Ctr Addict & Mental Hlth, Human Neurochem Pathol Lab, Clarke Div, 250 Coll St, Toronto, ON M5T 1R8, Canada. FU NIDA NIH HHS [DA 07182] NR 14 TC 43 Z9 44 U1 0 U2 4 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 FEB 15 PY 2001 VL 116 IS 2-3 BP 163 EP 169 DI 10.1016/S0379-0738(00)00368-6 PG 7 WC Medicine, Legal SC Legal Medicine GA 407LY UT WOS:000167274100009 PM 11182268 ER PT J AU Ongstad, AP Kaspi, R Moeller, CE Tilton, ML Gianardi, DM Chavez, JR Dente, GC AF Ongstad, AP Kaspi, R Moeller, CE Tilton, ML Gianardi, DM Chavez, JR Dente, GC TI Spectral blueshift and improved luminescent properties with increasing GaSb layer thickness in InAs-GaSb type-II superlattices SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID LASERS AB We describe the photoluminescence spectroscopy (PL) and Fourier transform infrared absorbance spectroscopy characterization of a large set of InAs/GaSb type-II strained layer superlattice (SLS) samples. The samples are designed to probe the effect of GaSb layer thickness on the optical properties of the SLS, while the InAs-layer thickness is held fixed. As the GaSb layer thickness is increased, we observe a spectral blue shift of the PL peaks that is accompanied by an increase in intensity, narrower linewidths, and a large reduction in the temperature sensitivity of the luminescence. These effects occur despite a significant reduction in the electron-hole wave function overlap as the GaSb layer thickness is increased. In addition, we compare the results of empirical pseudopotential model (EPM) calculations to the observed blueshift of the primary band gap. The EPM calculations are found to be in very good agreement with the observed data. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Directed Energy Directorate, AFRL DELS, Kirtland AFB, NM 87117 USA. Boeing Co, Def & Space Grp, Albuquerque, NM 87185 USA. GCD Associates, Albuquerque, NM 87110 USA. RP Ongstad, AP (reprint author), USAF, Res Lab, Directed Energy Directorate, AFRL DELS, Kirtland AFB, NM 87117 USA. NR 8 TC 36 Z9 36 U1 2 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD FEB 15 PY 2001 VL 89 IS 4 BP 2185 EP 2188 DI 10.1063/1.1337918 PG 4 WC Physics, Applied SC Physics GA 397HY UT WOS:000166688300029 ER PT J AU Seetharaman, V Semiatin, SL AF Seetharaman, V Semiatin, SL TI Microstructures and tensile properties of Ti-45.5Al-2Nb-2Cr rolled sheets SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE gamma titanium aluminides; heat treatments; mechanical properties; microstructure; thermechanical processing ID GAMMA-TITANIUM ALUMINIDE; TIAL-BASE ALLOYS; TEMPERATURE; DEFORMATION; DUCTILITY; CRYSTALS; FRACTURE; PST; AL AB Tension tests were carried out at 20, 704, 760, and 815 degreesC on sheet specimens machined from pack rolled and heat-treated sheets of a multi-phase gamma titanium aluminide alloy, Ti-45.5Al-2Nb-2Cr. The microstructures of the heat-treated sheets ranged from equiaxed, (recrystallized) primary gamma structure obtained by annealing at 1200 degreesC to the fine-grained, fully lamellar structure obtained by a short-term solution treatment at 1320 degreesC followed by air cooling to 900 degreesC. The yield strength and the tensile strength of specimens containing the equiaxed, primary gamma microstructure were consistently low at all test temperatures, while the strength properties of duplex and fully lamellar structures were comparatively quite high. The tensile ductility values showed a complex dependence on the microstructure and the test temperature. Fully lamellar structures exhibited poor ductility at all temperatures up to 815 degreesC. Fractography and metallography of the tensile test specimens revealed evidence of a mixture of failure mechanisms: cleavage cracking, ductile failure by microvoid coalescence, and intergranular fracture by cavitation and wedge cracking. The relative contributions of these mechanisms varied with the initial microstructure and the test temperature. Both the lamellar grains and the gamma grains became significantly elongated near the fracture zone, particularly in specimens deformed at 760 and 815 degreesC. The yield and tensile strength of Ti-45.5Al-2Nb-2Cr alloy sheets in all microstructural conditions were significantly higher than those reported for a majority of alloys containing 47-49% aluminum. However, the ductile-to-brittle transition temperatures of the Ti-45.5Al-2Nb-2Cr alloy were somewhat higher than those obtained for the majority of gamma titanium aluminides. (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, MLLM, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Mat & Proc Div, Dayton, OH 45432 USA. RP Seetharaman, V (reprint author), USAF, Res Lab, MLLM, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM venkat.seetharaman@afrl.af.mil RI SEMIATIN, SHELDON/E-7264-2017 NR 35 TC 17 Z9 19 U1 2 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 EI 1873-4936 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD FEB 15 PY 2001 VL 299 IS 1-2 BP 195 EP 209 DI 10.1016/S0921-5093(00)01396-4 PG 15 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 395BW UT WOS:000166559700022 ER PT J AU Semiatin, SL Fagin, PN Glavicic, MG Sukonnik, IM Ivasishin, OM AF Semiatin, SL Fagin, PN Glavicic, MG Sukonnik, IM Ivasishin, OM TI Influence on texture on beta grain growth during continuous annealing of Ti-6Al-4V SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE annealing; titanium; grain growth; texture ID CONVENTIONAL TITANIUM-ALLOY; HEAT-TREATMENT AB The kinetics of grain growth during continuous beta annealing of two different lots of Ti-6Al-4V bar stock with an equiaxed-alpha preform microstructure were determined using an induction-heating technique. Heating rates of 1.4, 5.6, and 18 degreesC s(-1) and peak temperatures between 1020 and 1260 degreesC were utilized. Noticeable differences were found in the grain-growth behaviors of the two lots of material with one exhibiting much smaller grain sizes than the other for a given set of processing conditions. A semi-quantitative analysis of the results revealed that the two batches of alloy had similar grain-growth exponents and activation energies but different rate constants. These trends were explained in terms of the beta-phase textures in the as-received materials which persisted during beta annealing. The former material had a moderate strength, cube-like texture, whereas the latter lot of material exhibited a very strong and sharper fiber texture. The grain-growth results were thus explained in terms of the effect of texture on grain-boundary surface energy/mobility. (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, MLLM, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. Lambda Res, Cincinnati, OH 45227 USA. Texas Instruments, Attleboro, MA 02703 USA. Natl Acad Sci Ukraine, Inst Met Phys, UA-252142 Kiev, Ukraine. RP Semiatin, SL (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLLM, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 16 TC 39 Z9 41 U1 1 U2 13 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 FEB 15 PY 2001 VL 299 IS 1-2 BP 225 EP 234 DI 10.1016/S0921-5093(00)01371-X PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 395BW UT WOS:000166559700025 ER PT J AU Russell, TH Roh, WB AF Russell, TH Roh, WB TI Incoherent beam combining using stimulated Brillouin scattering in multimode fibers SO OPTICS EXPRESS LA English DT Article ID LASER C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, DELO, Kirtland AFB, NM 87117 USA. RP Russell, TH (reprint author), USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. NR 7 TC 19 Z9 22 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD FEB 12 PY 2001 VL 8 IS 4 BP 246 EP 254 PG 9 WC Optics SC Optics GA 400XW UT WOS:000166898800003 PM 19417811 ER PT J AU Pandey, AB Majumbar, BS Miracle, DB AF Pandey, AB Majumbar, BS Miracle, DB TI Laminated particulate-reinforced aluminum composites with improved toughness SO ACTA MATERIALIA LA English DT Article DE discontinuously reinforced aluminum (DPA) composites; powder processing; fracture & fracture toughness ID FRACTURE-TOUGHNESS; MATRIX COMPOSITES; LAYER THICKNESS; DUCTILITY; ALLOYS AB An architectural approach for toughening discontinuously reinforced aluminum (DRA) alloys is described. It is based upon exploiting the higher apparent toughness of thin DRA lamina to obtain a laminate of higher thickness and toughness. The laminated composite consisted of alternate layers of a 7093/SiC/15p DRA, and an unreinforced aluminum-manganese alloy, 3003. Fracture toughness tests in the crack divider configuration showed a toughness improvement of 79% in an underaged condition and an improvement of 53% in the peak-aged condition compared to the monolithic DRA. Fractographic observations of the primary void size, and its close correspondence with the fracture surface of thin specimens, provided evidence that the individual DRA lamina indeed experienced sufficient loss of constraint in the thickness direction. This was further confirmed by observations of delamination in the fast fracture domain. However. the bond strength was quite good, as evidenced by very little delamination in the fatigue crack growth region, and by a lack of such damage in tension specimens. In essence, the laminate behaved as a smart structure, being resistant to failure under normal conditions, but allowing full loss of constraint in the severe stress-strain field ahead of a loaded crack. Modeling efforts were consistent with a reduction of hydrostatic stress, through the loss of out-of-plane constraint for the laminas, although the predicted level of toughness improvement was lower than observed. Overall, this study clearly demonstrates that the fracture toughness of laminated composites can be engineered based on the understanding of constraint effects associated with specimen thickness in the DRA composite. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Pratt & Whitney, Liquid Space Prop, W Palm Beach, FL 33410 USA. USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLLM, Wright Patterson AFB, OH 45433 USA. New Mexico Inst Min & Technol, Dept Met & Mat Sci, Socorro, NM 87801 USA. RP Pandey, AB (reprint author), Pratt & Whitney, Liquid Space Prop, W Palm Beach, FL 33410 USA. NR 25 TC 32 Z9 34 U1 9 U2 26 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD FEB 8 PY 2001 VL 49 IS 3 BP 405 EP 417 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 400KQ UT WOS:000166871100004 ER PT J AU Romaides, AJ Battis, JC Sands, RW Zorn, A Benson, DO DiFrancesco, DJ AF Romaides, AJ Battis, JC Sands, RW Zorn, A Benson, DO DiFrancesco, DJ TI A comparison of gravimetric techniques for measuring subsurface void signals SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article AB To demonstrate the potential of gravity gradiometry in the detection of underground structures or voids, an experiment was carried out at an underground missile launch facility at Vandenberg Air Force Base, California. Gravity data were collected using a LaCoste-Romberg Model G gravimeter and gravity gradient measurements were made using a vertical spin-axis Lockheed Martin developed arms control verification gravity gradiometer. After performing all necessary corrections, the data were compared to modelled signatures of the launch facility. Peak gravity and gravity gradient anomalies of approximately -75 mu Gal (1 mu Gal = 10(-8) m s(-1)) and 30 E(1 E = 10(-9) s(-2)) respectively were measured over the centreline of the largest capsule. The presence of the buried launch facility was apparent in both the observed gravity and gravity gradient data. The gravity gradients were unambiguous in resolving the underground facility's signature and thus revealing its location. In contrast, identifying the launch complex solely from the gravity anomaly data would have proven difficult due to a strong regional trend across the target area. C1 USAF, Res Lab, Hanscom AFB, MA 01731 USA. Dynam Res Corp, Andover, MA 01810 USA. Lockheed Martin Bell Aerosp Operat, Buffalo, NY 14240 USA. RP Romaides, AJ (reprint author), USAF, Res Lab, Hanscom AFB, MA 01731 USA. NR 7 TC 10 Z9 10 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD FEB 7 PY 2001 VL 34 IS 3 BP 433 EP 443 DI 10.1088/0022-3727/34/3/331 PG 11 WC Physics, Applied SC Physics GA 403ZE UT WOS:000167072300036 ER PT J AU Voevodin, AA Jones, JG Zabinski, JS AF Voevodin, AA Jones, JG Zabinski, JS TI Structural modification of single-axis-oriented yttria-stabilized-zirconia films under zirconium ion bombardment SO APPLIED PHYSICS LETTERS LA English DT Article ID PULSED-LASER DEPOSITION; BEAM-ASSISTED DEPOSITION; GROWTH; MICROSTRUCTURE; LAYERS; WEAR AB Crystal size and orientation control of yttria-stabilized-zirconia (YSZ) films produced by pulsed-laser deposition under zirconium-ion bombardment are reported. A structure development mechanism is proposed based on the correlation between ablated plasma chemistry, velocity distributions of atomic and molecular species in the plasma, bombardment energy, time, incidence angle, film crystal size, and orientation. A near-room-temperature growth of single-axis-oriented YSZ films with (002) texture on randomly oriented polycrystalline substrates is demonstrated. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, MLBT MLMR, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Voevodin, AA (reprint author), USAF, Res Lab, MLBT MLMR, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RI Voevodin, Andrey/I-6684-2013 NR 16 TC 12 Z9 12 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD FEB 5 PY 2001 VL 78 IS 6 BP 730 EP 732 DI 10.1063/1.1345823 PG 3 WC Physics, Applied SC Physics GA 398CF UT WOS:000166737800016 ER PT J AU Brannon, BC Carlton, PK AF Brannon, BC Carlton, PK TI AFNC clarifies stance SO AMERICAN JOURNAL OF NURSING LA English DT Letter C1 USAF, Off Surgeon Gen, Nursing Serv, Washington, DC 20330 USA. USAF, CFS, MC, Washington, DC 20330 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0002-936X J9 AM J NURS JI Am. J. Nurs. PD FEB PY 2001 VL 101 IS 2 BP 13 EP 14 PG 2 WC Nursing SC Nursing GA 442EV UT WOS:000169273000008 PM 11227222 ER PT J AU Gonzalez, DI Zahn, CM Retzloff, MG Moore, WF Kost, ER Snyder, RR AF Gonzalez, DI Zahn, CM Retzloff, MG Moore, WF Kost, ER Snyder, RR TI Recurrence of dysplasia after loop electrosurgical excision procedures with long-term follow-up SO AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY LA English DT Article DE loop electrosurgical excision procedure; positive margins; negative margins ID CERVICAL INTRAEPITHELIAL NEOPLASIA; TRANSFORMATION ZONE LLETZ; COLD-KNIFE CONIZATION; DIATHERMY EXCISION; POSITIVE MARGINS; MANAGEMENT; DIAGNOSIS; ABLATION; CYTOLOGY; BIOPSY AB OBJECTIVE: The aim of this study was to determine the rates of recurrent dysplasia with longer follow-up durations and to determine whether margin status and other variables were associated with recurrence. STUDY DESIGN: A retrospective chart review was performed for all women who underwent a loop electrosurgical excision procedure at Wilford Hall Medical Center, Lackland Air Force Base, Texas, between January 1993 and December 1994. Extracted information included age, parity, indication for the loop electrosurgical excision procedure, histologic classification of the loop electrosurgical excision procedure specimen, margin status, and whether a "deep" (endocervical) pass had been performed. Follow-up data included findings of repeated cytologic examination, colposcopy, and biopsy ii performed. RESULTS: The mean duration of follow-up for all women was 24 months. Margins were positive in 28%, with 73% of these being endocervical. The overall recurrent dysplasia rate was 31%, with a mean time to recurrence of 11.9 months. Participants with any positive margins had a higher recurrence rate than did those with negative margins (47% vs 26%; P = .009). High-grade lesions at the margin were more commonly associated with recurrence than were low-grade lesions relative to those with clear margins thigh-grade lesion vs negative margins, 55% vs 26%; P = .003; low-grade lesion vs negative margins, 36% vs 26%; P = .34). Recurrence was not associated either with the performance of an endocervical pass or with the histologic diagnosis of the loop electrosurgical excision procedure specimen. CONCLUSION: With comprehensive long-term follow-up, positive margins on loop electrosurgical excision procedure specimens were shown to be a risk factor for recurrence of cervical dysplasia, particularly when high-grade lesions were seen at the margin. Recurrence was also considerable among women with negative margins. Women should be counseled regarding this risk, and the importance of follow-up should be emphasized. C1 Wilford Hall USAF Med Ctr, Dept Obstet & Gynecol, Lackland AFB, TX 78236 USA. Brooke Army Med Ctr, Ft Sam Houston, TX 78234 USA. RP Gonzalez, DI (reprint author), Wilford Hall USAF Med Ctr, Dept Obstet & Gynecol, 2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 25 TC 37 Z9 39 U1 0 U2 0 PU MOSBY, 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 FEB PY 2001 VL 184 IS 3 BP 315 EP 321 PG 7 WC Obstetrics & Gynecology SC Obstetrics & Gynecology GA 408BF UT WOS:000167306100011 PM 11228480 ER PT J AU Robbins, AS Chao, SY Fonseca, VP Snedecor, MR Knapik, JJ AF Robbins, AS Chao, SY Fonseca, VP Snedecor, MR Knapik, JJ TI Predictors of low physical fitness in a cohort of active-duty US Air Force members SO AMERICAN JOURNAL OF PREVENTIVE MEDICINE LA English DT Article DE epidemiology; military personnel; physical fitness ID HERITAGE FAMILY; UNITED-STATES; BODY-FAT; EXERCISE; SMOKING; VO2MAX; ADULTS; MEN AB Background: Each branch of the U.S. armed forces has standards for physical fitness as well as programs for ensuring compliance with these standards. In the U.S. Air Force (USAF), physical fitness is assessed using submaximal cycle ergometry to estimate maximal oxygen uptake (VO2max). The purpose of this study was to identify the independent effects of demographic and behavioral factors on risk of failure to meet USAF fitness standards (hereafter called low fitness). Methods: A retrospective cohort study (N=38,837) was conducted using self-reported health risk assessment data and cycle ergometry data from active-duty Air Force (ADAF) members. Poisson regression techniques were used to estimate the associations between the factors studied and low fitness. Results: The factors studied had different effects depending on whether members passed or failed fitness testing in the previous year. All predictors had weaker effects among those with previous failure. Among those with a previous pass, demographic groups at increased risk were toward the upper end of the ADAF age distribution, senior enlisted men, and blacks. Overweight/obesity was the behavioral factor with the largest effect among men, with aerobic exercise frequency ranked second; among women, the order of these two factors was reversed. Cigarette smoking only had an adverse effect among men. For a hypothetical ADAF man who was sedentary, obese, and smoked, the results suggested that aggressive behavioral risk factor modification would produce a 77% relative decrease in risk of low fitness. Conclusions: Among ADAF members, both demographic and behavioral factors play important roles in physical fitness. Behavioral risk factors are prevalent and potentially modifiable. These data suggest that, depending on a member's risk factor profile, behavioral risk factor modification may produce impressive reductions in risk of low fitness among ADAF personnel. C1 USAF Med Operat Agcy, Hlth Innovat & Res Branch, Off Prevent & Hlth Serv Assessment, Brooks AFB, TX 78235 USA. USA, Ctr Hlth Promot & Prevent Med, Directorate Epidemiol & Dis Surveillance, Aberdeen Proving Ground, MD USA. RP Robbins, AS (reprint author), USAF Med Operat Agcy, Hlth Innovat & Res Branch, Off Prevent & Hlth Serv Assessment, 2602 Doolittle Rd,Bldg 804, Brooks AFB, TX 78235 USA. NR 32 TC 90 Z9 92 U1 1 U2 5 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0749-3797 J9 AM J PREV MED JI Am. J. Prev. Med. PD FEB PY 2001 VL 20 IS 2 BP 90 EP 96 DI 10.1016/S0749-3797(00)00280-4 PG 7 WC Public, Environmental & Occupational Health; Medicine, General & Internal SC Public, Environmental & Occupational Health; General & Internal Medicine GA 400JR UT WOS:000166868900002 PM 11165448 ER PT J AU Grayson, DE Wettlaufer, JR Dalrymple, NC Keesling, CA AF Grayson, DE Wettlaufer, JR Dalrymple, NC Keesling, CA TI Appendiceal CT in pediatric patients: Relationship of visualization to amount of peritoneal fat SO AMERICAN JOURNAL OF ROENTGENOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Roentgen-Ray-Society CY MAY 08, 2000 CL WASHINGTON, D.C. SP Amer Roentgen Ray Soc ID HELICAL CT AB OBJECTIVE. This study was performed to determine the rate of visualization of the nor mal pediatric appendix on CT and to evaluate the relationship of the appendix to parameters such as amount of intraperitoneal fat, use of contrast material, patient age, and slice thickness. MATERIALS AND METHODS. Three board-certified radiologists retrospectively reviewed 248 successive pediatric abdominal and pelvic CT examinations performed from 1995 to 1999. Each radiologist independently assessed the degree of intraperitoneal fat (minimal, moderate, or marked compared with a standard slice), appendiceal visualization (definite, unsure, not seen), cecal and terminal ileal opacification, and the outer diameter of visualized appendixes. The age and sex of the patient, collimation thickness (3-10 mm), and use of enteric or IV contrast material was also recorded. RESULTS. A normal appendix was identified in 120 (48.4%) of 248 examinations. The only individual variable with statistically significant correlation was the degree of intraperitoneal fat. This was determined using the Pearson chi-square test, the likelihood ratio, and logistic regression. The appendix was seen in 68.8% (n = 93) of patients with moderate or marked intraperitoneal fat versus 36.1% in = 155) with minimal fat (p < 0.001). A trend toward decreased visualization in children younger than 10 years old with minimal peritoneal fat was identified and confirmed with a 95% confidence limit. The outer diameter of the visualized appendix varied from 3 to 10 mm, with a mean value of 6 mm. CONCLUSION. Increased peritoneal fat significantly increases the rate of identification of the normal appendix in pediatric patients. Although less fat is generally seen in younger patients, there is significant overlap of appendix visualization among age groups. C1 Wilford Hall USAF Med Ctr, Dept Radiol, Lackland AFB, TX 78236 USA. RP Grayson, DE (reprint author), Wilford Hall USAF Med Ctr, Dept Radiol, 759th MDTS MTRD,2200 Bergquist Dr,ST 1, Lackland AFB, TX 78236 USA. NR 7 TC 31 Z9 31 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 FEB PY 2001 VL 176 IS 2 BP 497 EP 500 PG 4 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 395RB UT WOS:000166594100041 PM 11159103 ER PT J AU Marsh, CM Hannum, WH Trotman, CA Proffit, WR AF Marsh, CM Hannum, WH Trotman, CA Proffit, WR TI Design and effectiveness of a computer-based continuing education program for orthodontists SO ANGLE ORTHODONTIST LA English DT Article DE orthodontic continuing education; Internet delivery AB The design of computer-based continuing education for health professionals is an important consideration for Internet delivery because the size of graphic files greatly affects the speed with which information is delivered. Orthodontists who had indicated an interest in computer-based continuing education were shown via CD-ROM either a dynamic version of a computer continuing education program (with transitions and animations to liven up the content) or a plain version (identical content except that the transitions and animations were omitted). The program provided new information about superelastic arch wires for the initial stage of orthodontic treatment. For both versions, over 90% of the viewers thought the program was well done and provided useful information. Six of the orthodontists who received the dynamic version felt that the animations were distracting rather than helpful; only one who received the plain version felt that it was lifeless, A follow-up questionnaire showed that two-thirds of those who viewed the program had subsequently reviewed the performance data for the initial wire they were using and 20% had changed it, so the computer program was effective in changing clinical behavior. Those who saw the plain version also were more likely to have changed their clinical procedures. For Internet delivery of information to highly motivated professionals, it appears that transitions and animations are not necessary and may be more likely to decrease than increase the effectiveness of the teaching material. C1 Univ N Carolina, Sch Dent, Dept Orthodont, Chapel Hill, NC 27599 USA. USAF, Washington, DC 20330 USA. Univ N Carolina, Sch Educ, Chapel Hill, NC 27599 USA. RP Proffit, WR (reprint author), Univ N Carolina, Sch Dent, Dept Orthodont, Chapel Hill, NC 27599 USA. NR 10 TC 6 Z9 6 U1 0 U2 0 PU ANGLE ORTHODONTISTS RES EDUC FOUNDATION INC PI APPLETON PA 100 W LAWRENCE ST, SUITE 406,, APPLETON, WI 54911 USA SN 0003-3219 J9 ANGLE ORTHOD JI Angle Orthod. PD FEB PY 2001 VL 71 IS 1 BP 71 EP 75 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 398VP UT WOS:000166777400015 PM 11211301 ER PT J AU Stanczak, DE Stanczak, EM Awadalla, AW AF Stanczak, DE Stanczak, EM Awadalla, AW TI Development and initial validation of an Arabic version of the Expanded Trail Making Test: Implications for cross-cultural assessment SO ARCHIVES OF CLINICAL NEUROPSYCHOLOGY LA English DT Article AB The performances of Sudanese subjects, both normal and brain damaged, on an Arabic version of the Expanded Trail Making Test were compared to those of normal and brain-damaged subjects from. the United States, who completed the standard English version of this test. Preliminary psychometric properties of the Arabic version of the Expanded Trail Making Test were defined. Significant intergroup differences in performance were observed. Interestingly, the performances of Sudanese normals were found to be similar to those of U.S. brain-damaged subjects. The results are discussed in terms of reducing neuropsychological diagnostic errors attributable to ethnocultural factors. (C) 2001 National Academy of Neuropsychology. Published by Elsevier Science Ltd. C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Childrens Hosp Philadelphia, Philadelphia, PA 19104 USA. RP Stanczak, DE (reprint author), Psychol Res Serv, 59th Med Wing,MMCB,2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 13 TC 16 Z9 17 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0887-6177 J9 ARCH CLIN NEUROPSYCH JI Arch. Clin. Neuropsychol. PD FEB PY 2001 VL 16 IS 2 BP 141 EP 149 DI 10.1016/S0887-6177(99)00060-8 PG 9 WC Psychology, Clinical; Psychology SC Psychology GA 415JB UT WOS:000167716900003 PM 14590182 ER PT J AU Iwasaki, LR Haack, JE Nickel, JC Reinhardt, RA Petro, TM AF Iwasaki, LR Haack, JE Nickel, JC Reinhardt, RA Petro, TM TI Human interleukin-1 beta and interleukin-1 receptor antagonist secretion and velocity of tooth movement SO ARCHIVES OF ORAL BIOLOGY LA English DT Article DE cytokines; tooth movement; IL-1 beta; IL-1RA; gingival crevicular fluid ID GINGIVAL CREVICULAR FLUID; TUMOR-NECROSIS-FACTOR; PROSTAGLANDIN-E; GROWTH-FACTOR; CELLS; RELEASE; BONE AB The cytokines interleukin-1 beta (IL-1 beta) and IL-1 receptor antagonist (IL-1RA) probably play a part in orthodontic tooth movement. Here, the force magnitudes and the area of force application in the compressed periodontal ligament (PDL) were controlled and the velocity of tooth movement correlated with concentrations of IL-IB and IL-IRA in the gingival crevicular fluid (GCF). Seven individuals undergoing orthodontic treatment involving maxillary first premolar extractions and distal movement (bodily retraction) of the maxillary canines participated in the 84-day study. For each participant, continuous retraction forces were applied so that they received equivalent PDL stresses of 13 kPa for one canine and 4 kPa for the other. GCF cytokine concentrations from experimental and control teeth were expressed relative to total protein in the GCF and compared using an 'Activity Index' (AI) = Experimental (IL-1 beta /IL-1RA)/Control (IL-1 beta /IL-1RA). The results showed that the velocity of tooth movement in an individual was related to their At. The correlation between AI and tooth movement was stronger from the distal (R-d = 0.78) than from the mesial (R-m = 0.65) of retracted teeth. The results demonstrate that equivalent force systems produce individual differences in cytokine production, which correlate with interindividual differences in the velocity of canine retraction. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Nebraska, Med Ctr, Coll Dent, Dept Growth & Dev, Lincoln, NE 68583 USA. USAF, Dent Squadron 3, Elmendorf AFB, AK 99506 USA. Univ Nebraska, Med Ctr, Coll Dent, Dept Oral Biol, Lincoln, NE 68583 USA. Univ Nebraska, Med Ctr, Coll Dent, Dept Surg Specialities, Lincoln, NE 68583 USA. RP Iwasaki, LR (reprint author), Univ Nebraska, Med Ctr, Coll Dent, Dept Growth & Dev, POB 830740, Lincoln, NE 68583 USA. NR 22 TC 51 Z9 52 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0003-9969 J9 ARCH ORAL BIOL JI Arch. Oral Biol. PD FEB PY 2001 VL 46 IS 2 BP 185 EP 189 DI 10.1016/S0003-9969(00)00088-1 PG 5 WC Dentistry, Oral Surgery & Medicine SC Dentistry, Oral Surgery & Medicine GA 398WZ UT WOS:000166780600010 PM 11163326 ER PT J AU Cohen, M Walker, RG Jayaraman, S Barker, E Price, SD AF Cohen, M Walker, RG Jayaraman, S Barker, E Price, SD TI Spectral irradiance calibration in the infrared. XII. Radiometric measurements from the Midcourse Space Experiment SO ASTRONOMICAL JOURNAL LA English DT Article DE astronomical databases : miscellaneous; infrared radiation; methods : analytical; stars : late-type; techniques : spectroscopic AB We describe the series of absolute stellar irradiance calibration experiments conducted by the Mid-course Space Experiment (MSX). These experiments validate the published absolute irradiances of our primary and secondary standards, namely, alpha CMa and a set of bright K-M giant stars, and confirm their radiometric "closure" (relative irradiances). We also validate the absolute spectra of 29 of the fainter calibrators that have been previously published using MSX data. This work underpins the absolute calibrators provided for DIRBE, IRTS, ISO, our all-sky network of 422 fainter calibration stars (Paper X), and the MSX Point Source Catalog, and it is now being extended to accommodate calibrators for SIRTF. C1 Vanguard Res Inc, Scotts Valley, CA 95066 USA. USAF, Res Lab, VSBC, Hanscom AFB, MA 01731 USA. RP Cohen, M (reprint author), Vanguard Res Inc, Suite 204,5321 Scotts Valley Dr, Scotts Valley, CA 95066 USA. NR 15 TC 15 Z9 15 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD FEB PY 2001 VL 121 IS 2 BP 1180 EP 1191 DI 10.1086/318751 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 401QL UT WOS:000166939700048 ER PT J AU Jones, DR Marsh, RW AF Jones, DR Marsh, RW TI Psychiatric considerations in military aerospace medicine SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE aerospace psychiatry; aerospace medicine; health maintenance; military medicine; occupational medicine; performance; preventive medicine; safety; selection ID SENSITIVITY; AVIATORS AB Military aerospace medicine requires a psychiatric selection and certification process that determines not only the absence of significant mental disorders, but also the presence of positive qualities in the realms of motivation, ability and stability: not ail normal people are fit to fly. Other issues of aerospace psychiatry involve maintenance of mental resilience and hardiness during a flying career, aeromedical decisions about when to remove from flight duties and when to return, criteria for waivers for psychiatric conditions, use of medications for treatment of psychiatric symptoms, questions of substance abuse, and research in such areas as genetics. This report reviews the basis for military aerospace psychiatry, primarily as practiced in the United States Air Force (USAF), and presents some of its underlying principles as they apply to clinical situations. C1 USAF, Sch Aerosp Med, Neuropsychiat Branch, Div Aerosp Med, Brooks AFB, TX 78235 USA. RP Jones, DR (reprint author), 3558 Southview Ave, Montgomery, AL 36111 USA. NR 18 TC 7 Z9 8 U1 1 U2 3 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD FEB PY 2001 VL 72 IS 2 BP 129 EP 135 PG 7 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 398EJ UT WOS:000166743600007 PM 11211042 ER PT J AU Stansell, MJ Winters, WD Doe, RH Dart, BK AF Stansell, MJ Winters, WD Doe, RH Dart, BK TI Increased antibiotic resistance of E-coli exposed to static magnetic fields SO BIOELECTROMAGNETICS LA English DT Article DE permanent magnet; DC fields; antibiotic sensitivity; bacterial resistance; piperacillin ID BACILLUS-SUBTILIS; IN-VITRO; GROWTH AB The present study demonstrates that exposure of bacteria to medium strength static magnetic fields can significantly alter antibiotic sensitivity. Cultures of Escherichia coli were exposed to fields produced by permanent magnets. Samples of bacterial cultures continuously growing in the presence and in the absence of static magnetic fields were left untreated or were treated with an antibiotic and measured at 45 min intervals for cell growth and survival. It was found that exposure of E. coli to the static fields significantly increased antibiotic resistance. Bioelectromagnetics 22:129-137, 2001. Published 2001 Wiley-Liss, Inc.(dagger). C1 Wilford Hall USAF Med Ctr, Clin Res Squadron, CRES MSRL 59, Lackland AFB, TX 78236 USA. Univ Texas, Hlth Sci Ctr, Dept Microbiol, San Antonio, TX 78284 USA. RP Stansell, MJ (reprint author), Wilford Hall USAF Med Ctr, Clin Res Squadron, CRES MSRL 59, 1255 Wilford Hall Loop, Lackland AFB, TX 78236 USA. NR 18 TC 12 Z9 13 U1 2 U2 5 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0197-8462 J9 BIOELECTROMAGNETICS JI Bioelectromagnetics PD FEB PY 2001 VL 22 IS 2 BP 129 EP 137 DI 10.1002/1521-186X(200102)22:2<129::AID-BEM1016>3.3.CO;2-C PG 9 WC Biology; Biophysics SC Life Sciences & Biomedicine - Other Topics; Biophysics GA 396TP UT WOS:000166652900009 PM 11180259 ER PT J AU Muschinski, A Frehich, R Jensen, M Hugo, R Hoff, A Eaton, F Balsley, B AF Muschinski, A Frehich, R Jensen, M Hugo, R Hoff, A Eaton, F Balsley, B TI Fine-scale measurements of turbulence in the lower troposphere: An intercomparison between a kite- and balloon-borne, and a helicopter-borne measurement system SO BOUNDARY-LAYER METEOROLOGY LA English DT Article DE airborne turbulence measurements; energy dissipation rate; fine-wire anemometry; fine-wire thermometry; HELIPOD; structure parameters; Tethered Lifting System ID HOT-WIRE CALIBRATION; BOUNDARY-LAYER; COLD-WIRE; TEMPERATURE; FLOWS AB Two state-of-the-art, high-resolution, in situ turbulence measurement systems, which can be deployed at altitudes well above the atmospheric surface layer, are compared: the Tethered Lifting System (TLS) of the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado, Boulder, Colorado, and the helicopter-borne turbulence measurement system HELIPOD of the Technical University Braunschweig, Germany, and the University of Hanover, Germany. While the CIRES TLS is a fixed-point platform, HELIPOD is a moving platform. On the basis of data taken with the two systems in separate field campaigns, the system capabilities are quantified and discussed. Criteria for instrumental requirements are presented. It is shown that both the CIRES TLS and HELIPOD are well suited for measuring fine-scale turbulence that is characterized by very small temperature structure parameters 10(6) K-2 m(-2/3) and smaller) and very small energy dissipation rates (10(-7) m(2) s(-3) and smaller). The authors are not aware of any other turbulence measurement systems that have similar capabilities and can be deployed at altitudes of up to several kilometres. The HELIPOD is ideal for high-resolution horizontal measurements while the TLS is ideal for high-resolution vertical measurements using multiple sensors attached to a suspended line. C1 Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80305 USA. NOAA, Environm Technol Lab, Boulder, CO 80305 USA. USAF, Res Lab, DEBA, Kirtland AFB, NM 87117 USA. Aerodata Flugmesstech GmbH, D-38108 Braunschweig, Germany. RP Muschinski, A (reprint author), Univ Colorado, Cooperat Inst Res Environm Sci, Boulder, CO 80305 USA. NR 35 TC 26 Z9 26 U1 1 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0006-8314 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD FEB PY 2001 VL 98 IS 2 BP 219 EP 250 DI 10.1023/A:1026520618624 PG 32 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 382GG UT WOS:000165814200002 ER PT J AU Birman, V Byrd, LW AF Birman, V Byrd, LW TI Selected issues of mechanics of ceramic matrix composites SO COMPOSITE STRUCTURES LA English DT Article DE ceramic matrix composites; matrix cracks; vibrations; thermography ID CRACKING AB This paper presents four different problems of ceramic matrix composites (CMC) with matrix cracks. They include an evaluation of material constants and the stiffness matrix of a unidirectional lamina with bridging cracks. A nonlinear stress-strain relationship for a lamina subjected to an increasing uniaxial tension is derived accounting for the process of a continuous crack density change. Forced and free vibrations of woven ceramic matrix beams with matrix cracks are also considered by assumption that the dynamic stresses are sufficiently small to neglect their effect on the stiffness. Finally, theoretical foundations of thermography for a woven ceramic matrix beam are discussed and a closed-form solution for the surface temperature presented as a function of the matrix crack spacing and other parameters, (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Missouri, Engn Educ Ctr, St Louis, MO 63121 USA. USAF, Res Lab, VAST, Wright Patterson AFB, OH 45433 USA. RP Birman, V (reprint author), Univ Missouri, Engn Educ Ctr, 8001 Nat Bridge Rd, St Louis, MO 63121 USA. NR 16 TC 2 Z9 2 U1 2 U2 3 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 FEB PY 2001 VL 51 IS 2 BP 181 EP 190 DI 10.1016/S0263-8223(00)00140-9 PG 10 WC Materials Science, Composites SC Materials Science GA 402WL UT WOS:000167011100006 ER PT J AU Oberly, CE Long, L Rhoads, GL Carr, WJ AF Oberly, CE Long, L Rhoads, GL Carr, WJ TI ac loss analysis for superconducting generator armatures wound with subdivided Y-Ba-Cu-O coated tape SO CRYOGENICS LA English DT Article; Proceedings Paper CT Workshop on AC Losses CY OCT 18-19, 2000 CL YOKOHAMA, JAPAN DE fully penetrated ac loss; YBCO tape; superconducting armature ID THICK-FILMS; CONDUCTORS AB Advances in Y-Ba-Cu-O coated thin film tape may allow narrow filaments with very high current density on a thin metal alloy substrate which is separated from the superconductor by a dielectric buffer. These tapes will exhibit minimized ac loss by subdividing the Y-Ba-Cu-O layer with barriers which exhibit high electrical resistance. Assuming a fully penetrated magnetic field, low loss conductor concepts were incorporated into 1 MW armature designs for various configurations of Y-Ba-Cu-O conductors over the frequency range 50-1000 Hz. Low ac loss armature conductor designs are developed for megawatt class generators loss for both a 50-60 Hz utility application and a higher frequency aircraft application. Conductor design tradeoffs are discussed and ac loss minimization techniques compatible with realistic Y-Ba-Cu-O coated conductor processing are considered, The ac loss in Y-Ba-Cu-O armature windings of a synchronous alternator may for the first time permit practical, lightweight all-cryogenic generators which can deliver greater than or equal to megawatt at frequencies much greater than 50-60 Hz. (C) 2001 Published by Elsevier Science Ltd. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Heston Consulting, W Mifflin, PA 15122 USA. RP Oberly, CE (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 20 TC 32 Z9 33 U1 0 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD FEB PY 2001 VL 41 IS 2 BP 117 EP 124 DI 10.1016/S0011-2275(01)00057-1 PG 8 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 449BL UT WOS:000169664400008 ER PT J AU Elston, DM AF Elston, DM TI Who has time to teach these days? SO CUTIS LA English DT Editorial Material C1 USA, Brooke Army Med Ctr, Dept Dermatol, MCHE DD, Ft Sam Houston, TX 78234 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Elston, DM (reprint author), USA, Brooke Army Med Ctr, Dept Dermatol, MCHE DD, 3851 Roger Brooke Dr, Ft Sam Houston, TX 78234 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 650 AVENUE OF THE AMERICAS, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD FEB PY 2001 VL 67 IS 2 BP 104 EP 105 PG 2 WC Dermatology SC Dermatology GA 402ZR UT WOS:000167018500001 PM 11236215 ER PT J AU Elston, DM Hivnor, C AF Elston, DM Hivnor, C TI What's eating you? Dermacentor andersoni SO CUTIS LA English DT Article ID IN-VITRO C1 USA, Brooke Army Med Ctr, Dept Dermatol, MCHE,DD, Ft Sam Houston, TX 78234 USA. Wilford Hall USAF Med Ctr, Dept Dermatol, San Antonio, TX 78236 USA. RP Elston, DM (reprint author), USA, Brooke Army Med Ctr, Dept Dermatol, MCHE,DD, 3851 Roger Brook Dr, Ft Sam Houston, TX 78234 USA. NR 8 TC 0 Z9 0 U1 0 U2 3 PU EXCERPTA MEDICA INC PI NEW YORK PA 650 AVENUE OF THE AMERICAS, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD FEB PY 2001 VL 67 IS 2 BP 113 EP 115 PG 3 WC Dermatology SC Dermatology GA 402ZR UT WOS:000167018500005 PM 11236219 ER PT J AU Ritter, SE Elston, DM AF Ritter, SE Elston, DM TI Cutaneous schwannoma of the foot SO CUTIS LA English DT Article ID BENIGN; NEUROFIBROMATOSIS; NEURILEMOMA AB Schwannomas usually present as solitary subcutaneous tumors adherent to a peripheral nerve. A solitary cutaneous schwannoma presenting as a solitary cutaneous nodule on the foot of a 19-year-old male is described. This is an unusual presentation of schwannoma, Saucerized excision produced an excellent result with no adverse effect on function or cutaneous sensation. C1 USA, Brooke Army Med Ctr, Dept Dermatol, MCHE,DD, Ft Sam Houston, TX 78234 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Univ Texas, Hlth Sci Ctr, San Antonio, TX USA. RP Elston, DM (reprint author), USA, Brooke Army Med Ctr, Dept Dermatol, MCHE,DD, 3851 Roger Brooke Dr, Ft Sam Houston, TX 78234 USA. NR 18 TC 7 Z9 8 U1 0 U2 1 PU EXCERPTA MEDICA INC PI NEW YORK PA 650 AVENUE OF THE AMERICAS, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD FEB PY 2001 VL 67 IS 2 BP 127 EP 129 PG 3 WC Dermatology SC Dermatology GA 402ZR UT WOS:000167018500008 PM 11236222 ER PT J AU Velappan, N Snodgrass, JL Hakovirta, JR Marrone, BL Burde, S AF Velappan, N Snodgrass, JL Hakovirta, JR Marrone, BL Burde, S TI Rapid identification of pathogenic bacteria by single-enzyme amplified fragment length polymorphism analysis SO DIAGNOSTIC MICROBIOLOGY AND INFECTIOUS DISEASE LA English DT Article ID MARKERS AB Despite major progress in their treatment and prevention, bacterial infections remain a significant cause of morbidity and mortality worldwide. In responding to a disease outbreak, rapid and accurate identification of the bacterial species involved is of paramount importance. Strain level discrimination is desirable to allow selection of treatment modalities, and in the case of a deliberate release, for identification of the source. Single-enzyme amplified fragment length polymorphism (SE-AFLP) analysis was used to perform species and strain identification of subgroup I Bacilli, Yersinia, Staphylococci and Escherichia coli. By careful selection of AFLP primers, it was possible to obtain reproducible and sensitive identification to strain level, even within the highly monomorphic species Bacillus anthracis. SE-AFLP fragments can be analyzed using standard gel electrophoresis, and can be easily scored by visual inspection, due to the low complexity of the fingerprint obtained by this method. These features make SE-AFLP suitable for use in either field or laboratory applications. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. USAF Acad, Colorado Springs, CO 80840 USA. RP Marrone, BL (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, POB 1663,MS M888, Los Alamos, NM 87545 USA. NR 6 TC 13 Z9 24 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0732-8893 J9 DIAGN MICR INFEC DIS JI Diagn. Microbiol. Infect. Dis. PD FEB PY 2001 VL 39 IS 2 BP 77 EP 83 DI 10.1016/S0732-8893(00)00235-2 PG 7 WC Infectious Diseases; Microbiology SC Infectious Diseases; Microbiology GA 413LE UT WOS:000167613000002 PM 11248519 ER PT J AU Grene, H Pinto, LA Landay, AL Kessler, HA Anderson, SA Dolan, MJ Shearer, GM AF Grene, H Pinto, LA Landay, AL Kessler, HA Anderson, SA Dolan, MJ Shearer, GM TI Anti-CCR5 antibodies in sera of HIV-positive individuals SO HUMAN IMMUNOLOGY LA English DT Article DE HIV infection; chemokines; CCR5 ID CHEMOKINE RECEPTOR; CCR5; INDUCTION; INFECTION AB One Of the proposed mechanisms for resistance to human immunodeficiency virus-1 (HIV-1) injection is the presence of antibodies against receptor for CC-chemokines (CCR5). These antibodies, detected in sera of uninfected individuals exposed to HIV, have been shown to downmodulate surface CCR5 in vivo and are able co neutralize thr infectivity of CCR5 strains in vitro. To address the potential rt,le of anti-CCR5 antibodies in HN infection, we analyzed anti-CCR5 antibody levels in plasma from HIV-infected patients who present a wide range of CD4(+) T-cell counts and viral load. Increased levels of anti-CCR5 antibodies were found in plasma from 13/46 HIV-positive donors compared with healthy controls (0/36). However, antibody levels were not associated with disease stage evaluated by CD4(+) T-cell counts and viral load. (C) American Society for Histocompatibility and Immunogenetics, 2001. Published by Elsevier Science Inc. C1 NCI, Expt Immunol Branch, NIH, Bethesda, MD 20892 USA. Rush Presbyterian St Lukes Med Ctr, Dept Immunol Microbiol, Chicago, IL 60612 USA. Rush Presbyterian St Lukes Med Ctr, Dept Med, Chicago, IL 60612 USA. Henry M Jackson Fdn, San Antonio, TX USA. Wilford Hall USAF Med Ctr, Infect Dis Serv, San Antonio, TX 78236 USA. RP Shearer, GM (reprint author), NCI, Expt Immunol Branch, NIH, Bldg 10,Room 4B36, Bethesda, MD 20892 USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0198-8859 J9 HUM IMMUNOL JI Hum. Immunol. PD FEB PY 2001 VL 62 IS 2 BP 143 EP 145 PG 3 WC Immunology SC Immunology GA 405CZ UT WOS:000167141200007 ER PT J AU Alford, LD AF Alford, LD TI The problem with aviation COTS SO IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE LA English DT Article AB Commercial Off the Shelf (COTS) has become a byword for acquisition reform, but there are significant risks associated with the use of COTS products in military systems. These risks are especially acute for aviation systems. This paper explains how COTS can negatively affect military acquisitions and gives ideas on how to plan and resolve COTS caused problems. C1 USAF, HQ AFMC, DOP, Wright Patterson AFB, OH 45433 USA. RP Alford, LD (reprint author), USAF, HQ AFMC, DOP, Area A,Bldg 262,Room S143,4375 Chidlaw Rd, Wright Patterson AFB, OH 45433 USA. NR 0 TC 6 Z9 7 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 0885-8985 J9 IEEE AERO EL SYS MAG JI IEEE Aerosp. Electron. Syst. Mag. PD FEB PY 2001 VL 16 IS 2 BP 33 EP 37 DI 10.1109/62.904242 PG 5 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA 403YT UT WOS:000167067200005 ER PT J AU Shore, RA Yaghjian, AD AF Shore, RA Yaghjian, AD TI Shadow boundary incremental length diffraction coefficients applied to scattering from 3-D bodies SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE high-frequency scattering; incremental length diffraction coefficients (ILDC); physical optics (PO); shadow boundary ID EQUIVALENT EDGE CURRENTS; ELECTROMAGNETIC SCATTERING; REVOLUTION AB Shadow boundary incremental length diffraction coefficients (SBILDCs) are high-frequency fields designed to correct the physical optics (PO) field of a three-dimensional (3-D) perfectly electrically conducting scatterer. The SBILDCs are integrated along the shadow boundary of the 3-D object to approximate the field radiated by the nonuniform shadow boundary current (the difference between the exact and PO currents near the shadow boundary), This integral is added to the PO field to give an approximation to the exact scattered field that takes into account both PO and nonuniform shadow boundary currents on the scatterer. Like other incremental length diffraction coefficients, any SBILDC is based on the use of a 2-D canonical scatterer to locally approximate the surface of the 3-D scatterer to which it is applied. Circular cylinder SBILDCs are, to date, the only SBILDCs that have been obtained in closed form. In this paper, these closed-form expressions are validated by applying them for the first time to a 3-D scatterer with varying radius of curvature-the prolate spheroid. The results obtained clearly demonstrate that for bistatic scattering the combined PO-SBILDC approximation is considerably more accurate than the PO held approximation alone. C1 USAF, Bedford, MA 01731 USA. RP Shore, RA (reprint author), USAF, Bedford, MA 01731 USA. NR 17 TC 11 Z9 12 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-926X J9 IEEE T ANTENN PROPAG JI IEEE Trans. Antennas Propag. PD FEB PY 2001 VL 49 IS 2 BP 200 EP 210 DI 10.1109/8.914277 PG 11 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 417EN UT WOS:000167822600008 ER PT J AU Mailloux, RJ AF Mailloux, RJ TI A low-sidelobe partially overlapped constrained feed network for time-delayed subarrays SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE antenna feeds; beamsteering; phased arrays ID ARRAYS AB Completely overlapped space-fed subarrays have been shown to provide sufficient pattern control to enable (modestly) wide-band arrays using time delays at the input to each subarray and phase shifters at the array face. These configurations are bulky, but have been proposed for space-based use as well as for certain ground-based applications that do not have severe volume constraints, Other applications for space-based and airborne radar require much more compact, constrained array feed networks, but until now there have been few appropriate constrained networks for inserting time delay at the subarray ports without causing high sidelobes, This paper describes one such network that, at the outset, provided far lower sidelobes than the usual contiguous subarrays, but retained closely spaced high lobes near the main beam. This paper presents a synthesis procedure that alters the subarray patterns and reduces nearly all array sidelobes to levels determined by tolerance errors. Several examples are presented that synthesize sidelobes at -40 dB, The resulting network operates over 70% to 80% of the maximum theoretical bandwidth. C1 USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. RP Mailloux, RJ (reprint author), USAF, Res Lab, Sensors Directorate, Hanscom AFB, MA 01731 USA. NR 9 TC 17 Z9 17 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 FEB PY 2001 VL 49 IS 2 BP 280 EP 291 DI 10.1109/8.914295 PG 12 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 417EN UT WOS:000167822600016 ER PT J AU Davidovitz, M AF Davidovitz, M TI An approach to analysis of waveguide arrays with shaped dielectric inserts and protrusions SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE matching; phased array; waveguide AB The classical moment method solution of the waveguide-array problem is extended to allow for generally shaped dielectric matching inserts in the waveguide-to-free-space transition region. The aperture electric field is represented in terms of waveguide modes. To account for the presence of the matching inserts, the aperture fields are numerically propagated through the dielectric regions. Novel matching configurations, which extend the scanning range of waveguide elements or can be used to shape the element pattern in limited-scan applications, are proposed and analyzed. C1 USAF, Res Lab, SNHA, Hanscom AFB, MA 01731 USA. RP Davidovitz, M (reprint author), USAF, Res Lab, SNHA, Hanscom AFB, MA 01731 USA. NR 8 TC 5 Z9 6 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 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD FEB PY 2001 VL 49 IS 2 BP 355 EP 361 DI 10.1109/22.903097 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 402ZT UT WOS:000167018600014 ER PT J AU Degnan, JH Taccetti, JM Cavazos, T Clark, D Coffey, SK Faehl, RJ Frese, MH Fulton, D Gueits, JC Gale, D Hussey, TW Intrator, TP Kirpatrick, RC Kiuttu, GH Lehr, FM Letterio, JD Lindemuth, I McCullough, WF Moses, R Peterkin, RE Reinovsky, RE Roderick, NF Ruden, EL Shlachter, JS Schoenberg, KF Siemon, RE Sommars, W Turchi, PJ Wurden, GA Wysocki, F AF Degnan, JH Taccetti, JM Cavazos, T Clark, D Coffey, SK Faehl, RJ Frese, MH Fulton, D Gueits, JC Gale, D Hussey, TW Intrator, TP Kirpatrick, RC Kiuttu, GH Lehr, FM Letterio, JD Lindemuth, I McCullough, WF Moses, R Peterkin, RE Reinovsky, RE Roderick, NF Ruden, EL Shlachter, JS Schoenberg, KF Siemon, RE Sommars, W Turchi, PJ Wurden, GA Wysocki, F TI Implosion of solid liner for compression of field reversed configuration SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE capacitor bank; Field reversed configuration; FRC; implosion; magnetized target fusion; megamp; MTF; radiography; solid liner ID ELECTROMAGNETIC IMPLOSION; FUSION AB The design and first successful demonstration of an imploding solid liner with height to diameter ratio, radial convergence, and uniformity suitable for compressing a field reversed configuration is discussed. Radiographs indicated a very symmetric implosion with no instability growth, with similar to 13 x radial compression of thp inner liner surface prior to impacting a central measurement unit. The implosion kinetic energy was 1.5 megajoules, 34% of the capacitor stored energy of 4.4 megajoules, C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Maxwell Technol Inc, Albuquerque, NM 87106 USA. NumerEx, Albuquerque, NM 87106 USA. Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. RP Degnan, JH (reprint author), USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 25 TC 26 Z9 26 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD FEB PY 2001 VL 29 IS 1 BP 93 EP 98 DI 10.1109/27.912947 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 416DT UT WOS:000167765500014 ER PT J AU Bradley, WR Wyatt, SE Wells, JR Henley, MV Graziano, GM AF Bradley, WR Wyatt, SE Wells, JR Henley, MV Graziano, GM TI The hydroxyl radical reaction rate constant and products of cyclohexanol SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID ATMOSPHERIC TRANSFORMATION PRODUCTS; RELATIVE RATE-CONSTANT; GAS-PHASE REACTIONS; METHYL NITRITE; OH RADICALS; KINETICS; ETHER; MECHANISM; OXIDATION; NITRATE AB The gas phase reaction of the hydroxyl radical (OH) with cyclohexanol (COL) has been studied. The rate coefficient was determined to be (19.0 +/- 4.8) X 10(-12) cm(3) molecule(-1) s(-1) (at 297 +/- 3 K and 1 atmosphere total pressure) using the relative rate technique with pentanal, decane, and tridecane as the reference compounds. Assuming an average OH concentration of 1 x 10(6) molecules cm(-3), an atmospheric lifetime of 15 h is calculated for cyclohexanol. Products of the OH + COL reaction were determined to more clearly define COL's atmospheric degradation mechanism. The observed products and their Formation yields were: cyclohexanone (0.55 +/- 0.06), hexanedial (0.32 +/- 0.15), 3-hydroxycyclohexanone (0.31 +/- 0.14), and 4-hydroxycyclohexanone (0.08 +/- 0.04). Consideration of the potential reaction pathways suggests that each of these products is formed via hydrogen abstraction at a different site on the COL ring. The products and their relative amounts are discussed in light of the predicted yields For each reaction channel. (C) 2001 lohn Wiley C Sons, Inc. C1 Appl Res Associates, Gulf Coast Div, Tyndall AFB, FL 32403 USA. USAF, Res Lab, Airbase & Environm Technol Div, AFRL,MLQE, Tyndall AFB, FL 32403 USA. RP Wyatt, SE (reprint author), Appl Res Associates, Gulf Coast Div, POB 40128,Bldg 1142,Mississippi Rd, Tyndall AFB, FL 32403 USA. NR 24 TC 10 Z9 10 U1 1 U2 11 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD FEB PY 2001 VL 33 IS 2 BP 108 EP 117 DI 10.1002/1097-4601(200102)33:2<108::AID-KIN1002>3.0.CO;2-# PG 10 WC Chemistry, Physical SC Chemistry GA 394CH UT WOS:000166506100003 ER PT J AU Ornstein, DL Zacharski, LR AF Ornstein, DL Zacharski, LR TI Treatment of cancer with anticoagulants: Rationale in the treatment of melanoma SO INTERNATIONAL JOURNAL OF HEMATOLOGY LA English DT Article DE anticoagulant tissue factor; thrombin; cancer; melanoma ID CELL LUNG-CANCER; TISSUE FACTOR; THROMBIN GENERATION; MALIGNANT-MELANOMA; RANDOMIZED TRIAL; TUMOR-CELLS; WARFARIN; HEPARIN; COAGULATION; METASTASIS AB The blood coagulation mechanism regulates the growth and dissemination of malignancy by multiple mechanisms, and anticoagulant drugs have been shown to inhibit the progression of certain cancers. Although progress has been slow, there is ample information on the effects of anticoagulants in various tumors that suggests that the use of anticoagulants has considerable potential in the treatment of some cancers. For example, melanoma is one of a small number of human tumor types in which the tumor is associated with an intact coagulation pathway leading to thrombin generation and conversion of fibrinogen to fibrin in situ immediately adjacent to viable tumor cells. Observations in experimental models combined with the limited clinical trial data on this subject suggest that inhibition of tumor cell thrombin generation may improve outcomes in melanoma cases. Thus, we postulate that pharmacological interruption of the tumor cell-associated coagulation pathway at any one step or even at multiple levels might constitute effective therapy for this disease. Drugs that block the activity of tissue factor. factor Xa, or thrombin are available for clinical testing and, if effective, offer the prospect of a relatively nontoxic, novel treatment for this aggressive tumor. (C) 2001 The Japanese Society of Hematology. C1 Wilford Hall USAF Med Ctr, MMIH, MDW, Dept Hematol Oncol, Lackland AFB, TX 78236 USA. Dartmouth Coll, Hitchcock Med Ctr, Dartmouth Med Sch, Hanover, NH 03756 USA. Vet Adm Med Ctr, White River Junction, VT USA. RP Ornstein, DL (reprint author), Wilford Hall USAF Med Ctr, MMIH, MDW, Dept Hematol Oncol, 2200 Berquist Dr, Lackland AFB, TX 78236 USA. NR 33 TC 22 Z9 22 U1 0 U2 0 PU CARDEN JENNINGS PUBL CO LTD PI CHARLOTTESVILLE PA BLAKE CTR, STE 200, 1224 W MAIN ST, CHARLOTTESVILLE, VA 22903 USA SN 0925-5710 J9 INT J HEMATOL JI Int. J. Hematol. PD FEB PY 2001 VL 73 IS 2 BP 157 EP 161 DI 10.1007/BF02981932 PG 5 WC Hematology SC Hematology GA 444LK UT WOS:000169400800004 PM 11372726 ER PT J AU Gao, XL Mall, S AF Gao, XL Mall, S TI Variational solution for a cracked mosaic model of woven fabric composites SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article DE woven fabric composites; mosaic model; variational solution; principle of minimum complementary energy; cross-ply laminates; theory of elasticity; damage modeling ID LAMINATE AB A variational solution for a cracked mosaic laminate model of woven fabric composites is presented using the principle of minimum complementary energy. The solution is derived for the woven laminate in either the plane strain or the plane stress state, with the warp/fill yarn materials being either orthotropic or transversely isotropic, unlike other existing solutions in the literature of laminate elasticity. The stress components are given in closed-form expressions in terms of a perturbation function, which is governed by two (uncoupled) fourth-order inhomogeneous ordinary differential equations (i.e., Euler-Lagrange equations) when the thermal effects are included. All possible expressions of this perturbation function are obtained in closed forms. Young's modulus of the cracked laminate is calculated using the determined minimum complementary energy. The present closed-form solution can account for different yam materials, applied loads (crack densities), geometrical dimensions, or their combinations. To demonstrate the solution, a total of 60 sample cases are analyzed using three different composite systems (i.e., glass fiber/epoxy, graphite fiber/ epoxy and ceramic fiber/ceramic) and ten different crack densities. The obtained numerical results are also compared to two existing elasticity solutions for cross-ply laminates. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, ENY, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, MLLN, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Gao, XL (reprint author), Michigan Technol Univ, Dept Engn Mech, 1400 Townsend Dr, Houghton, MI 49931 USA. NR 19 TC 22 Z9 22 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD FEB PY 2001 VL 38 IS 5 BP 855 EP 874 DI 10.1016/S0020-7683(00)00047-0 PG 20 WC Mechanics SC Mechanics GA 391YX UT WOS:000166384800007 ER PT J AU Bernstein, JA Garramone, SM Lower, EE AF Bernstein, JA Garramone, SM Lower, EE TI Successful treatment of autoimmune chronic idiopathic urticaria with intravenous cyclophosphamide SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 Univ Cincinnati, Cincinnati, OH 45221 USA. Wright Patterson Air Force Base, Dayton, OH USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY, 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 FEB PY 2001 VL 107 IS 2 SU S MA 184 BP S53 EP S53 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA 405RE UT WOS:000167172300184 ER PT J AU Loesevitz, AW Cossentino, MJ Benson, PM Hoangxuan, TA Haga, LL Hoffman, K Grabenstein, JD Engler, RJM AF Loesevitz, AW Cossentino, MJ Benson, PM Hoangxuan, TA Haga, LL Hoffman, K Grabenstein, JD Engler, RJM TI Anthrax vaccine related adverse events: Non-localized cutaneous reactions SO JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY LA English DT Meeting Abstract C1 Walter Reed Army Med Ctr, Washington, DC 20307 USA. Madigan Army Med Ctr, Tacoma, WA 98431 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Mil & Vet Hlth Coordinating Board, Washington, DC USA. US Army Med Command, Falls Church, VA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MOSBY, 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 FEB PY 2001 VL 107 IS 2 SU S MA 25 BP S8 EP S8 PG 1 WC Allergy; Immunology SC Allergy; Immunology GA 405RE UT WOS:000167172300026 ER PT J AU Jackson, A Newton, B Hahn, D Bussey, A AF Jackson, A Newton, B Hahn, D Bussey, A TI Statistical contrail forecasting SO JOURNAL OF APPLIED METEOROLOGY LA English DT Article AB The current operational Air Force Weather Agency condensation trail (contrail) forecast technique is based on the Appleman algorithm, developed in the 1950s, with minor modifications. The Appleman algorithm requires accurate measurements or forecasts of ambient flight-level temperature, relative humidity, and pressure, as well as the amount of heat and water vapor added by an aircraft to its exhaust to determine accurately the critical temperature for contrail formation. Several factors contribute to the relatively poor contrail forecasts produced by the Air Force Weather Agency contrail forecast technique, including insufficiently accurate atmospheric measurements and numerical weather prediction forecasts of temperature and humidity at flight level, as well as some of the procedures used in the Air Force Weather Agency's implementation of the Appleman algorithm. The Contrail Field Program was conducted in eastern Massachusetts during a 10-day period in September 1995. Radiosonde data and aircraft observations were collected from a five-station network. Radiosondes were launched every 3 h, and aircraft observations included aircraft type, aircraft speed, aircraft altitude, and whether the aircraft produced a contrail. This dataset of nearly coincident (in time and space) radiosonde and aircraft observations was used to develop a new statistical regression contrail prediction model and to compare the results of the new statistical model with nowcasts produced by the Schrader algorithm, which is very similar to the Air Force Weather Agency contrail prediction technique, known as "JETRAX." The Statistical Contrail Forecast Model makes use of logistic regression techniques to relate the presence or absence of observed contrails with nearly coincident radiosonde measurements. The statistical model produced a correct diagnosis of contrail occurrence or nonoccurrence for 85% of the observations, as compared with 58% correct for the Schrader technique, for this particular dataset. C1 USAF, Res Lab, VSBE, Hanscom AFB, Bedford, MA 01731 USA. RP Jackson, A (reprint author), USAF, Res Lab, VSBE, Hanscom AFB, Bedford, MA 01731 USA. OI Hahn, Douglas/0000-0003-0755-7904 NR 17 TC 10 Z9 10 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8763 J9 J APPL METEOROL JI J. Appl. Meteorol. PD FEB PY 2001 VL 40 IS 2 BP 269 EP 279 DI 10.1175/1520-0450(2001)040<0269:SCF>2.0.CO;2 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 401VH UT WOS:000166948900011 ER PT J AU Jiao, CQ DeJoseph, CA Garscadden, A AF Jiao, CQ DeJoseph, CA Garscadden, A TI A mass spectrometry study of n-octane: Electron impact ionization and ion-molecule reactions SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SPARK-IGNITION; RATE CONSTANTS; PROPAGATION; BREAKDOWN; SIMULATION; EXCITATION AB Electron impact ionization of n-octane over an energy range of 10-70 eV and the subsequent ion-molecule reactions with the parent molecule have been studied using Fourier-transform mass spectrometry. Molecular ion and fragment ions C-1(+)-C-6(+) are produced from the electron impact with a total ionization cross section of 1.4 +/-0.2x10(-15) cm(2) between 60 and 70 eV. C3H7+ is the most abundant ion at most of the ionizing energies with the exception for E less than or equal to 16 eV where C6H13+ and C6H12+ are the most abundant. Among the fragment ions only C4H7+ and smaller ions react readily with the parent molecule, primarily producing C5H11+ and C4H9+, with rate coefficients of 0.32-2.4x10(-9) cm(3) s(-1). Essentially all of the ions, including the molecular ion and the large fragment ions, undergo decomposition upon collision with neutral molecules after they are kinetically excited to an energy range of 1-5 eV, forming a variety of small hydrocarbon ions. Many of the decomposition product ions in turn are capable of further reacting with n-octane. Isotope reagents have been utilized in experiments to probe the type of the ion-molecule reactions studied. (C) 2001 American Institute of Physics. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Mobium Enterprises Inc, Dayton, OH 45431 USA. RP Garscadden, A (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 38 TC 12 Z9 12 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD FEB 1 PY 2001 VL 114 IS 5 BP 2166 EP 2172 DI 10.1063/1.1334898 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 397CQ UT WOS:000166676100028 ER PT J AU Huang, CY Burke, WJ Hardy, DA Gough, MP James, HG Villalon, E Gentile, LC AF Huang, CY Burke, WJ Hardy, DA Gough, MP James, HG Villalon, E Gentile, LC TI Electron acceleration by megahertz waves during OEDIPUS C SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article AB Observations of Electric Field Distributions in the Ionospheric Plasma - A Unique Strategy (OEDIPUS C) was a tethered mother-son experiment that was launched northward from the Poker Flat rocket range at 0638 UT on November 7, 1995, across a sequence of auroral structures. During the flight's upleg the magnetically aligned tet;her was deployed to a separation of similar to1.2 km and then cut at both ends. The forward payload contained a 50-kHz to 8-MHz stepped-frequency transmitter. Receivers were carried on both forward and aft payloads. The transmitter swept through the frequency range every 0.5 s. During each of the 3-ms steps the transmitter emitted only for the first 0.3 ms. The scientific complement also included multiangular electrostatic analyzers on both payloads that; were sensitive to fluxes of electrons with energies from 20 eV to 20 keV. The durations of sampling and frequency steps were matched. During the flight the electron gyrofrequency was approximately twice the plasma frequency. When the transmitter swept through the local gyrofrequency, the particle detectors on both payloads detected sounder-accelerated electrons (SAEs) independent of the energy stops being sampled. In addition, SAEs were detected at the aft payload out to separations of several hundred meters for wave emissions at harmonics of the electron gyrofrequency as well as in the upper hybrid and whistler bands. As the vehicle separation increased, significant lime differences developed between the wa ire-emission pulses and the onsets/durations of SAE detections. The data indicate that electrons were heated through strong wave-particle interactions. However, a simple resonant-interaction explanation appears inadequate. We outline requirements for any models purporting to explain OEDIPUS C:measurements. C1 Boston Coll, Inst Sci Res, Chestnut Hill, MA 02467 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. Univ Sussex, Ctr Space Sci, Brighton BN1 9QT, E Sussex, England. Ctr Commun Res, Dept Commun, Ottawa, ON K2H 8S7, Canada. Northeastern Univ, Ctr Electromagnet Res, Boston, MA 02115 USA. RP Huang, CY (reprint author), Boston Coll, Inst Sci Res, 402 St Clements Hall,140 Commonwealth Ave, Chestnut Hill, MA 02467 USA. NR 11 TC 8 Z9 8 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD FEB 1 PY 2001 VL 106 IS A2 BP 1835 EP 1847 DI 10.1029/1999JA000286 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 395HV UT WOS:000166575700009 ER PT J AU Castle, RM Thomas, SK Yerkes, KL AF Castle, RM Thomas, SK Yerkes, KL TI The effect of working fluid inventory on the performance of revolving helically grooved heat pipes SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article DE experimental; heat transfer; heat pipes; porous media; two-phase AB The results of a recently completed experimental and analytical study showed that the capillary limit of a helically-grooved heat pipe (HGHP) was increased significantly when the transverse body force field was increased. This was due to the geometry of the helical groove wick structure. The objective of the present research was to experimentally determine the performance of revolving helically-grooved heat pipes when the working fluid inventory was varied. This report describes the measurement of the geometry of the heat pipe wick structure and the construction and testing of a heat pipe filling station. In addition, an extensive analysis of the uncertainty involved in the filling procedure and working fluid inventory has been outlined. Experimental measurements include the maximum heat transport, thermal resistance and evaporative heat transfer coefficient of the revolving helically grooved heat pipe for radial accelerations of \(a) over right arrow (r)\ = 0.0, 2.0, 4.0, 6.0, 8.0, and 10.0-g and working fluid fills of G = 0.5, 1.0, and 1.5. An existing capillary limit model was updated and comparisons were made to the present experimental data. C1 Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. USAF, Res Lab, PRPG, Wright Patterson AFB, OH 45433 USA. RP Castle, RM (reprint author), Wright State Univ, Dept Mech & Mat Engn, Dayton, OH 45435 USA. NR 17 TC 1 Z9 2 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD FEB PY 2001 VL 123 IS 1 BP 120 EP 129 DI 10.1115/1.1339982 PG 10 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA 409DE UT WOS:000167368600015 ER PT J AU Gazitt, Y Shaughnessy, P Liu, Q AF Gazitt, Y Shaughnessy, P Liu, Q TI Differential mobilization of CD34(+) cells and lymphoma cells in non-Hodgkin's lymphoma patients mobilized with different growth factors SO JOURNAL OF HEMATOTHERAPY & STEM CELL RESEARCH LA English DT Article ID COLONY-STIMULATING FACTOR; BLOOD STEM-CELLS; HEMATOPOIETIC PROGENITOR CELLS; FACTOR G-CSF; HIGH-DOSE CHEMOTHERAPY; BCL-2 PROTEIN EXPRESSION; CLONAL MYELOMA CELLS; PERIPHERAL-BLOOD; PROGNOSTIC-SIGNIFICANCE; MULTIPLE-MYELOMA AB Co-mobilization of CD34(+) cells and tumor has been documented in patients with different types of cancer undergoing peripheral blood stem cell transplantation (PBSCT). Conflicting reports were published regarding the role of various growth factors in tumor cells mobilization, hence we studied the extent of CD34(+) cells and lymphoma cell mobilization in 35 non-Hodgkin's (NHL) patients primed by cyclophosphamide (Cy) in combination with granulocyte colony-stimulating factor (GCSF) (A, 13 patients), granulocyte-macrophage (GM)-CSF (B, 10 patients), or GM-CSF followed by G-CSF (C, 12 patients). CD34(+) cells were quantitated by flow cytometry and lymphoma cells by the TaqMan Real Time PCR for bcl-2 gene rearrangement. Successful collection in 4 days of greater than or equal to2 x 10(6) CD34(+) cells/kg needed for prompt engraftment was obtained in 76%, 60%, and 58% of patients in arms A, B, and C, respectively. Lymphoma cell mobilization was detected in 35% patients tested, 78% of which had follicular lymphoma. Lymphoma cell mobilization was similar in the three arms of the study, however, presence of lymphoma cells was prevalent in patients who failed to mobilize the amount of 0.4 x 10(6) CD34(+) cells/kg in 2 days ("poor mobilizers") and reached 42%, compared to 17% in the "successful mobilizers" group of patients. Lymphoma cell contamination in PBSCs was detected proportionately in the peripheral blood and in the bone marrow. We conclude that bcl-2 gene rearrangement is prevalent in patients with follicular histology, and, in these patients, an inverse relationship was observed between mobilization of CD34(+) cells and lymphoma cells. Our results explain the high relative risk (1.98) for mobilization in patients with follicular histology. C1 Univ Texas, Hlth Sci Ctr, San Antonio, TX 78284 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78284 USA. RP Gazitt, Y (reprint author), Univ Texas, Hlth Sci Ctr, 7703 Floyd Curl Dr, San Antonio, TX 78284 USA. NR 41 TC 18 Z9 18 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1525-8165 J9 J HEMATOTH STEM CELL JI J. Hematother. Stem Cell Res. PD FEB PY 2001 VL 10 IS 1 BP 167 EP 176 DI 10.1089/152581601750098453 PG 10 WC Hematology; Medicine, Research & Experimental; Transplantation SC Hematology; Research & Experimental Medicine; Transplantation GA 415UW UT WOS:000167742800020 PM 11276370 ER PT J AU Gazitt, Y Shaughnessy, P Devore, P AF Gazitt, Y Shaughnessy, P Devore, P TI Mobilization of dendritic cells and NK cells in non-Hodgkin's lymphoma patients mobilized with different growth factors SO JOURNAL OF HEMATOTHERAPY & STEM CELL RESEARCH LA English DT Article ID COLONY-STIMULATING FACTOR; BLOOD PROGENITOR CELLS; HIGH-DOSE CHEMOTHERAPY; FACTOR G-CSF; HEMATOPOIETIC STEM-CELLS; NATURAL-KILLER-CELLS; PERIPHERAL-BLOOD; BONE-MARROW; LANGERHANS CELLS; CD34(+) CELLS AB Conflicting results have been reported regarding the effect of various growth factors on the mobilization of natural killer (NK) cells and dendritic cells in patients undergoing stem cell mobilization for autotransplantation. We compared the extent of mobilization of NK cells and dendritic cells in non-Hodgkin's (NHL) patients undergoing mobilization with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage (GM)-CSF, or GM-CSF followed by G-CSF. Overall, 35 patients were studied. NK cells and dendritic were quantitated by flow cytometry. NK cells were defined as the sum of CD56(+) cells and CD56/CD16(+) cells. Dendritic cells were defined as the sum of CD80(+) and CD80(+)/CD14(+) cells. NK activity was determined by by microcytotoxicity assay. NK activity correlated well with the total amount of CD56(+) cells mobilized to the peripheral blood. Patients in the three arms of the study mobilized similar amounts of NK cells and NK activity, and patients who lacked NK activity in the peripheral blood, before mobilization, lacked NK activity in their apheresis collections. In contrast to NK cell mobilization, mobilization of dendritic cells/kg was three- to five-fold higher in patients mobilized with GM-CSF-containing regimens compared to patients mobilized with G-CSF alone. We conclude that GM-CSF-containing mobilization regimens are superior for dendritic cell mobilization but similar in the mobilization of NK cells. Therefore, we recommend using GM-CSF-containing regimens for patients undergoing ex vivo or in vivo manipulation of dendritic cells. C1 Univ Texas, Hlth Sci Ctr, San Antonio, TX 78286 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78286 USA. RP Gazitt, Y (reprint author), Univ Texas, Hlth Sci Ctr, San Antonio, TX 78286 USA. NR 42 TC 20 Z9 20 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 1525-8165 J9 J HEMATOTH STEM CELL JI J. Hematother. Stem Cell Res. PD FEB PY 2001 VL 10 IS 1 BP 177 EP 186 DI 10.1089/152581601750098471 PG 10 WC Hematology; Medicine, Research & Experimental; Transplantation SC Hematology; Research & Experimental Medicine; Transplantation GA 415UW UT WOS:000167742800021 PM 11276371 ER PT J AU Tam, S Fajardo, ME AF Tam, S Fajardo, ME TI CO/pH(2): A molecular thermometer SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT 3rd International Conference on Cryocrystals and Quantum Crystals (CC 2000) CY JUL 28-AUG 04, 2000 CL SZKLARSKA, POLAND ID MATRIX-ISOLATION SPECTROSCOPY; HIGH-RESOLUTION SPECTROSCOPY; SOLID PARAHYDROGEN; ROVIBRATIONAL STATES; PHOTOINDUCED REACTIONS; THERMAL-CONDUCTIVITY; HEAT-TRANSFER; CLUSTERS; NEON; IMPURITY AB We utilize reversible temperature dependent changes in the IR absorption spectrum of Co molecules isolated in solid parahydrogen (pH(2)) to probe bulk temperature changes during rapid vapor deposition. The intensity of a well resolved feature near 2135 cm(-1) increases monotonically with temperature over the 2 to 5 K range. The thermally populated initial state of this transition lies approximate to 12 K above the CO/pH(2) ground state. During the deposition of similar to 100 ppm Co/pH(2) samples, we detect temperature gradients similar to 10 K/cm in similar to 0.1 cm-thick samples subjected to heat loads similar to 10 mW/cm(2). The resulting estimated thermal conductivity (TC) is 3(+/-2) mW/cm-K, averaged over the 2 to 5 K region. This values is similar to 1000 times lower than the TC of single crystal solid pH(2), and similar to 10 times lower than previously measured for pH(2) solids doped with 100 ppm concentrations of heavy impurities [Manzhelii, Gorodilov, and Krivchikov, Low Temp. Phys. 22, 131 (1996)]. We attribute this abnormally low TC to the known mixed fcc/hcp structure of the rapid vapor deposited solids. C1 USAF, Res Lab, Propuls Directorate, AFRL,PRSP, Edwards AFB, CA 93524 USA. RP Tam, S (reprint author), USAF, Res Lab, Propuls Directorate, AFRL,PRSP, Bldg 8451, Edwards AFB, CA 93524 USA. NR 43 TC 11 Z9 11 U1 1 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD FEB PY 2001 VL 122 IS 3-4 BP 345 EP 357 DI 10.1023/A:1004805018743 PG 13 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 426JF UT WOS:000168345500026 ER PT J AU Palm-Leis, A Arevelo, TV Pickard, JS Kruyer, WB AF Palm-Leis, A Arevelo, TV Pickard, JS Kruyer, WB TI Natural history of lone atrial fibrillation in 234 males: Follow-up of 22 years SO JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY LA English DT Meeting Abstract C1 USAF, Sch Med, Brooks AFB, TX USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0735-1097 J9 J AM COLL CARDIOL JI J. Am. Coll. Cardiol. PD FEB PY 2001 VL 37 IS 2 SU A BP 112A EP 113A PG 2 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 401EM UT WOS:000166914400517 ER PT J AU Fitzsimmons, PJ Thompson, WT Barnett, S Kruyer, WB AF Fitzsimmons, PJ Thompson, WT Barnett, S Kruyer, WB TI Natural history of asymptomatic angiographic coronary artery disease in 575 young men: Long-term study of 15 years SO JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY LA English DT Meeting Abstract C1 USAF, Sch Aerosp Med, Brooks AFB, TX 78235 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0735-1097 J9 J AM COLL CARDIOL JI J. Am. Coll. Cardiol. PD FEB PY 2001 VL 37 IS 2 SU A BP 235A EP 236A PG 2 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 401EM UT WOS:000166914401078 ER PT J AU O'Bryan, CL White, DS Guidera, S Saad, RM AF O'Bryan, CL White, DS Guidera, S Saad, RM TI The use of mitral valve resistance in the evaluation of native mitral valve stenosis SO JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY 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 ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0735-1097 J9 J AM COLL CARDIOL JI J. Am. Coll. Cardiol. PD FEB PY 2001 VL 37 IS 2 SU A BP 487A EP 488A PG 2 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA 401EM UT WOS:000166914402216 ER PT J AU Barchers, JD Ellerbroek, BL AF Barchers, JD Ellerbroek, BL TI Improved compensation of turbulence-induced amplitude and phase distortions by means of multiple near-field phase adjustments SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID MULTICONJUGATE ADAPTIVE OPTICS; LASER-BEAM PROJECTION; OF-VIEW; SCINTILLATION; RETRIEVAL; SYSTEM; DESIGN AB An approach for compensation of turbulence-induced amplitude and phase distortions is described. Two deformable mirrors are placed optically conjugate to the collecting aperture and to a finite range from this aperture. Two control algorithms are presented. The first is a sequential generalized projection algorithm (SGPA) that is similar to the Gerchberg-Saxton phase retrieval algorithm. The second is a parallel generalized projection algorithm (PGPA) that introduces constraints that minimize the number of branch points in the control commands for the deformable mirrors. These approaches are compared with the approach of placing the second deformable mirror conjugate to the far field of the collecting aperture and using the Gerchberg-Saxton algorithm to determine the optimal mirror commands. Simulation results show that placing the second deformable mirror at a finite range can achieve near-unity Strehl ratio regardless of the strength of the scintillation induced by propagation through extended paths, while the maximum Strehl ratio of the far-field approach drops off with increasing scintillation. The feasibility of the solutions is evaluated by counting the branch points contained in the deformable mirror commands. There are large numbers of branch points contained in the control commands that are generated by the Gerchberg-Saxton SGPA-based algorithms, irrespective of where the second deformable mirror is located. However, the control commands generated by the PGPA with branch point constraints achieves excellent Strehl ratio and minimizes the number of branch points. (C) 2001 Optical Society of America OCIS codes: 010.1080, 010.1300, 010.1330. C1 USAF, Res Lab, Directed Energy Directorate, Starfire Opt Range, Kirtland AFB, NM 87117 USA. Gemini Observ, Hilo, HI 96720 USA. RP Barchers, JD (reprint author), USAF, Res Lab, Directed Energy Directorate, Starfire Opt Range, Kirtland AFB, NM 87117 USA. NR 20 TC 27 Z9 28 U1 0 U2 5 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 FEB PY 2001 VL 18 IS 2 BP 399 EP 411 DI 10.1364/JOSAA.18.000399 PG 13 WC Optics SC Optics GA 396JU UT WOS:000166633400019 PM 11205987 ER PT J AU Aultman, CJ Soares, G Grayson, DE AF Aultman, CJ Soares, G Grayson, DE TI Transnasal removal of a biliary endoprosthesis with percutaneous transhepatic biliary catheter replacement SO JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY LA English DT Article DE bile ducts, stenosis or obstruction; bile ducts, stents and prostheses ID STENT AB The authors describe a novel fluoroscopically guided transnasal technique for removal of an endoscopically placed endobiliary prosthesis (EBP). A case in which the approach was applied is used to demonstrate its indications, clinical utility and possible benefits. The procedure entails simultaneous percutaneous replacement of the EBP with an internal/external biliary catheter over a through-and-through transhepatic/transnasal access wire. A comparison of the technique's limitations with those of traditional approaches for endoscopic or percutaneous EBP removal and replacement is presented. C1 Wilford Hall USAF Med Ctr, Dept Radiol, Div Vasc & Intervent Radiol, Lackland AFB, TX 78236 USA. RP Soares, G (reprint author), Wilford Hall USAF Med Ctr, Dept Radiol, Div Vasc & Intervent Radiol, 759th MDTS-MTRD,2200 Bergquist Dr,ST 1, Lackland AFB, TX 78236 USA. NR 12 TC 3 Z9 3 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 1051-0443 J9 J VASC INTERV RADIOL JI J. Vasc. Interv. Radiol. PD FEB PY 2001 VL 12 IS 2 BP 257 EP 260 DI 10.1016/S1051-0443(07)61834-X PG 4 WC Radiology, Nuclear Medicine & Medical Imaging; Peripheral Vascular Disease SC Radiology, Nuclear Medicine & Medical Imaging; Cardiovascular System & Cardiology GA 402QE UT WOS:000166999000017 PM 11265892 ER PT J AU Chozinski, JP Bourgeois, JA AF Chozinski, JP Bourgeois, JA TI Psychiatric profiles in the US Air Force: A clinical interpretation of Air Force Instruction 48-123 SO MILITARY MEDICINE LA English DT Article ID MILITARY AB The foundations of our current system for profiling military psychiatric patients were laid during World War II, well before the development of the first version of the Diagnostic and Statistical Manual of Mental Disorders. The general principles and terminology remain in use today through Air Force Instruction 48-123, Medical Examination and Standards. The terminology used is clearly outdated, making it difficult to use and risking misuse, deploying the wrong person or denying deployment to an appropriate person. Our objective is to review the current standards for making psychiatric profiles in the U.S. Air Force and propose a practical interpretation of the current Air Force Instruction. Considerable research remains to be done to improve our profile system, especially in light of the development of effective treatments for many psychiatric illnesses. Although prognostic data are available for some illnesses, little research has been done on military populations and essentially none of it considers the rigors of military deployment. Diagnosis, prognosis, duty environments, and demands-of duties all must be considered in making profile decisions. Reductionistic approaches more simple than this will serve neither the commander nor the airman. C1 Wilford Hall USAF Med Ctr, Med Wing 59, Neurobehav Sci Flight, Lackland AFB, TX 78236 USA. RP Chozinski, JP (reprint author), Wilford Hall USAF Med Ctr, Med Wing 59, Neurobehav Sci Flight, Lackland AFB, TX 78236 USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD FEB PY 2001 VL 166 IS 2 BP 112 EP 115 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 403XN UT WOS:000167068600004 PM 11272706 ER PT J AU Loomis, GA Connolly, KP Clinch, CR Djuric, DA AF Loomis, GA Connolly, KP Clinch, CR Djuric, DA TI Attitudes and practices of military family physicians regarding obesity SO MILITARY MEDICINE LA English DT Article; Proceedings Paper CT Scientific Assembly of the Uniformed-Services-Academy-of-Family-Physicians CY MAR 01-05, 1998 CL LAS VEGAS, NEVADA SP Uniform Serv Acad Family Phsician ID UNITED-STATES AB This study's objective was to define the current attitudes and practices of military family physicians regarding obesity. The authors mailed a cross-sectional survey to 267 military family physicians selected randomly from the 1997 Uniformed Services Academy of Family Physicians membership database. A total of 214 surveys (80%) were returned. Most respondents believed that they should be role models to patients (93%) and felt obligated to counsel patients regarding obesity (90%). Fifty-six percent did not consider counseling obese patients professionally satisfying. Most correctly identified obesity as a risk factor for several diseases, except colon cancer (35%). Fifty-four percent correctly identified the current World Health Organization definition of obesity. A notable minority ascribed negative attributes of sadness (18%) and lack of self-control (25%) to obese individuals. The results of this survey indicate knowledge gaps and professional ambivalence regarding obesity in the study group. Methods of increasing family physician effectiveness in modifying this important risk factor deserve further study. C1 Malcolm Grow Med Ctr, Family Practice Residency, Andrews AFB, MD 20762 USA. RP Loomis, GA (reprint author), Malcolm Grow Med Ctr, Family Practice Residency, 1075 W Perimeter Rd, Andrews AFB, MD 20762 USA. NR 23 TC 15 Z9 15 U1 1 U2 3 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD FEB PY 2001 VL 166 IS 2 BP 121 EP 125 PG 5 WC Medicine, General & Internal SC General & Internal Medicine GA 403XN UT WOS:000167068600006 PM 11272708 ER PT J AU Hutchison, BG All, AC Loving, GL Nishikawa, HA AF Hutchison, BG All, AC Loving, GL Nishikawa, HA TI Values identified in different groups of Air Force nurses SO MILITARY MEDICINE LA English DT Article ID JOB AB Fundamental personal values are reflected in the choices and decisions made in every aspect of our lives. This descriptive study identified values held by a convenience sample of 224 Air Force nurses stationed at four U.S. Air Force medical facilities. Study participants identified seven of eight literature-supported values in the categories "important" or "very important" across the demographic factors of age, gender, educational level, military rank, marital status, and years of Air Force or civilian nursing experience. These seven values were ability utilization, achievement, altruism, autonomy, economic reward, economic security, and personal development. Personnel using this information may ease the transition process to military nursing, facilitate job placement to positions reflecting personally held values, and provide valuable insight for Air Force nurse recruiters who have limited knowledge of the nursing profession. In all, this would promote job satisfaction and Air Force nurse retention. C1 SGGP, Med Grp 72, Tinker AFB, OK 73145 USA. RP Hutchison, BG (reprint author), SGGP, Med Grp 72, 5700 Arnold,Bldg 5801, Tinker AFB, OK 73145 USA. NR 21 TC 6 Z9 6 U1 0 U2 2 PU ASSN MILITARY SURG US PI BETHESDA PA 9320 OLD GEORGETOWN RD, BETHESDA, MD 20814 USA SN 0026-4075 J9 MIL MED JI Milit. Med. PD FEB PY 2001 VL 166 IS 2 BP 139 EP 145 PG 7 WC Medicine, General & Internal SC General & Internal Medicine GA 403XN UT WOS:000167068600010 PM 11272712 ER PT J AU Nizette, M Erneux, T Gavrielides, A Kovanis, V AF Nizette, M Erneux, T Gavrielides, A Kovanis, V TI Stability and bifurcations of periodically modulated, optically injected laser diodes SO PHYSICAL REVIEW E LA English DT Article ID SEMICONDUCTOR-LASER; PERTURBED BIFURCATION; NONLINEAR DYNAMICS; HOPF-BIFURCATION; GENERATION; SUBJECT AB Recent experiments using lasers subject to external injection [T. B. Simpson, Opt. Commun., 170, 93 (1999)] have shown remarkable locking performances when a small reference current modulation is added to the de-bias current. The locking problem is studied analytically by using a multiple scale perturbation method. We derive a slow time amplitude equation for the laser rapid limit-cycle oscillations. The solution of this equation is then investigated both analytically and numerically using a continuation method. We find that the intensity of the laser field can be time periodic (locking) or quasiperiodic (unlocking) and that there exist two distinct bifurcation mechanisms leading to locking. Finally, we compare bifurcation diagrams based on our amplitude equation with diagrams obtained from the laser original equations and find a good quantitative agreement. C1 Free Univ Brussels, B-1050 Brussels, Belgium. USAF, Res Lab, Nonlinear Opt Ctr, Kirtland AFB, NM 87117 USA. RP Nizette, M (reprint author), Free Univ Brussels, Campus Plaine,Code Postal Interne 231, B-1050 Brussels, Belgium. NR 25 TC 12 Z9 12 U1 0 U2 2 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 FEB PY 2001 VL 63 IS 2 AR 026212 DI 10.1103/PhysRevE.63.026212 PN 2 PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 403BK UT WOS:000167022500037 PM 11308563 ER PT J AU Yoder, TI Zheng, HQ Todd, P Staehelin, LA AF Yoder, TI Zheng, HQ Todd, P Staehelin, LA TI Amyloplast sedimentation dynamics in maize columella cells support a new model for the gravity-sensing apparatus of roots SO PLANT PHYSIOLOGY LA English DT Article ID CELLULAR TENSEGRITY; GRAVITROPISM; CYTOSKELETON; ACTIN; ARABIDOPSIS; MICROGRAVITY; PERCEPTION; STATOLITHS; POLARITY; PATTERN AB Quantitative analysis of statolith sedimentation behavior was accomplished using videomicroscopy of living columella cells of corn (Zen mays) roots, which displayed no systematic cytoplasmic streaming. Following 90 degrees rotation of the root, the statoliths moved downward along the distal wall and then spread out along the bottom with an average velocity of 1.7 mum min(-1). When statolith trajectories traversed the complete width or length of the cell, they initially moved horizontally toward channel-initiation sites and then moved vertically through the channels to the lower side of the reoriented cell where they again dispersed. These statoliths exhibited a significantly lower average velocity than those sedimenting on distal-to-side trajectories. In addition, although statoliths undergoing distal-to-side sedimentation began at their highest velocity and slowed monotonically as they approached the lower cell membrane, statoliths crossing the cell's central region remained slow initially and accelerated to maximum speed once they reached a channel. The statoliths accelerated sooner, and the channeling effect was less pronounced in roots treated with cytochalasin D. Parallel ultrastructural studies of high-pressure frozen-freeze-substituted columella cells suggest that the low-resistance statolith pathway in the cell periphery corresponds to the sharp interface between the endoplasmic reticulum (ER)-rich cortical and the ER-devoid central region of these cells. The central region is also shown to contain an actin-based cytoskeletal network in which the individual, straight, actin-like filaments are randomly distributed. To explain these findings as well as the results of physical simulation experiments, we have formulated a new, tensegrity-based model of gravity sensing in columella cells. This model envisages the cytoplasm as pervaded by an actin-based cytoskeletal network that is denser in the ER-devoid central region than in the ER-rich cell cortex and is linked to stretch receptors in the plasma membrane. Sedimenting statoliths are postulated to produce a directional signal by locally disrupting the network and thereby altering the balance of forces acting on the receptors in different plasma membrane regions. C1 Univ Colorado, MCD Biol, Boulder, CO 80309 USA. USAF Acad, Dept Astronaut Engn, Colorado Springs, CO 80840 USA. Univ Colorado, Dept Aerosp Engn Sci, BioServe Space Technol Ctr, Boulder, CO 80309 USA. RP Staehelin, LA (reprint author), Univ Colorado, MCD Biol, Boulder, CO 80309 USA. NR 47 TC 86 Z9 93 U1 0 U2 13 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 USA SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD FEB PY 2001 VL 125 IS 2 BP 1045 EP 1060 DI 10.1104/pp.125.2.1045 PG 16 WC Plant Sciences SC Plant Sciences GA 412FQ UT WOS:000167544700055 PM 11161060 ER PT J AU Guo, W DeJoseph, CA AF Guo, W DeJoseph, CA TI Time-resolved current and voltage measurements on a pulsed rf inductively coupled plasma SO PLASMA SOURCES SCIENCE & TECHNOLOGY LA English DT Article ID ENERGY-DISTRIBUTIONS; REFERENCE CELL; ARGON PLASMAS; DISCHARGES; DENSITY AB Time resolved current and voltage measurements have been made on a pulsed radio frequency (rf) inductively coupled plasma (ICP) at 13.56 MHz in argon. Measurements were made on the rf coil using a high-voltage probe, a Rogowski current probe, and a high-performance digital oscilloscope. Relative phase information was also obtained so that time resolved rf power measurements could be made. Due to the inductive nature of the load, measurement of the phase had to be: better than 0.6 mrad at 13.56 MHz in order that the power measurements were accurate to 10%. This accuracy in phase measurement was achieved by careful positioning of the probes and by establishing accurate phase calibration procedures. The power was calculated by three methods: discrete Fourier transform, integral of the current voltage product over N periods, and least-squares fits of a sine wave to the measured data. Time-resolved measurements of the system complex impedance, power loss in the ICP planar coil, and the actual amount of rf power delivered to the plasma were made, These measurements give details during plasma breakdown and show the transition from capacitive to inductive discharge, The results are compared with both time-resolved plasma emission and time-resolved Langmuir probe measurements. C1 Innovat Sci Solut Inc, Dayton, OH 45440 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Guo, W (reprint author), Innovat Sci Solut Inc, 2766 Indian Ripple Rd, Dayton, OH 45440 USA. NR 18 TC 26 Z9 26 U1 0 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0963-0252 J9 PLASMA SOURCES SCI T JI Plasma Sources Sci. Technol. PD FEB PY 2001 VL 10 IS 1 BP 43 EP 51 DI 10.1088/0963-0252/10/1/307 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 408DU UT WOS:000167311900007 ER PT J AU Vaia, RA Tomlin, DW Schulte, MD Bunning, TJ AF Vaia, RA Tomlin, DW Schulte, MD Bunning, TJ TI Two-phase nanoscale morphology of polymer/LC composites SO POLYMER LA English DT Article DE polymer dispersed liquid crystal; polymerization-induced phase separation; small angle X-ray scattering ID DISPERSED LIQUID-CRYSTALS; SCATTERING; SEPARATION; GRATINGS AB Small-angle X-ray scattering and high-resolution scanning electron microscopy (SAXS/KRSEM) were utilized to examine the nano(1-100 nm) and meso (100-1000 nm) scale morphology of polymer dispersed liquid crystal (PDLC) films of varying liquid crystal (LC) concentration. In contrast to the conventional PDLCs derived from photo-initiated step-growth polymerizations, these PDLC films were formed using photo-irradiation of initially homogeneous syrup comprised of highly functional free-radical monomer and liquid crystal, resulting in rapid molecular weight increase and network formation prior to or in conjunction with phase separation. Two-phase morphology observable with HRSEM was absent below 20% LC, although fine, small modulation features existed on the fracture surface. In contrast, SAXS reveals increasing nanoscale heterogeneity with increasing LC content. The scattering behavior is consistent with a structure factor derived from an Omstein-Zernicke model indicating that composition fluctuations frozen by network formation exist at the lowest LC concentrations. At higher LC concentrations, a discontinuous LC phase is observed which coalesce into a co-continuous polymer/LC phase between 35 and 40% LC. Above this regime, aggregated beads of polymer form whose size and uniformity steadily increase with concentration. These morphological observations are consistent with analysis of the SAXS data via a two component Debye-Bueche model at low q. The nanoscale features of the PDLCs formed from highly functional free-radical monomers underscore the importance of the polymerization mechanism in controlling the two-phase morphology in PDLCs. (C) 2000 Published by Elsevier Science Ltd. C1 USAF, Res Lab, Mat & Mfg Directorate, MLPJ, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, MLBP, Wright Patterson AFB, OH 45433 USA. RP Bunning, TJ (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLPJ, 3005 P St,Bldg 651, Wright Patterson AFB, OH 45433 USA. NR 20 TC 37 Z9 39 U1 2 U2 14 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 FEB PY 2001 VL 42 IS 3 BP 1055 EP 1065 DI 10.1016/S0032-3861(00)00462-6 PG 11 WC Polymer Science SC Polymer Science GA 365QT UT WOS:000089962500023 ER PT J AU Vaia, RA Giannelis, EP AF Vaia, RA Giannelis, EP TI Liquid crystal polymer nanocomposites: direct intercalation of thermotropic liquid crystalline polymers into layered silicates SO POLYMER LA English DT Article DE nanocomposites; nematic state; liquid crystalline polymers ID POLY(ETHYLENE OXIDE); MELT INTERCALATION; INCLUSION-COMPOUNDS; MODEL; DYNAMICS AB Reversible intercalation between two ordered media such as organically modified layered silicates (OLS) and thermotropic liquid crystalline polymers (LCP) in the nematic state is demonstrated. These results indicate that the decreased diffusivities and intermolecular interactions of an ordered polymeric guest do not preclude intercalation, potentially enabling fabrication of ultra-high performance polymer nanocomposites. Fundamentally, the polymer-polymer interactions that lead to a preferred orientation director in the bulk LCP nematic state are suppressed when the chains are confined to the pseudo two-dimensional environment of the OLS interlayer, resulting in a loss of liquid crystallinity. This demonstrates a finite-size effect on the nematic state of thermotropic liquid crystalline polymers. (C) 2000 Published by Elsevier Science Ltd. C1 USAF, Res Lab, Mat & Mfg Directorate, MLBP, Wright Patterson AFB, OH 45433 USA. Cornell Univ, Dept Mat Sci & Engn, Ithaca, NY 14853 USA. RP Vaia, RA (reprint author), USAF, Res Lab, Mat & Mfg Directorate, MLBP, Bldg 654,2941 P St, Wright Patterson AFB, OH 45433 USA. NR 23 TC 67 Z9 70 U1 1 U2 9 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 FEB PY 2001 VL 42 IS 3 BP 1281 EP 1285 DI 10.1016/S0032-3861(00)00508-5 PG 5 WC Polymer Science SC Polymer Science GA 365QT UT WOS:000089962500047 ER PT J AU Lincoln, DM Vaia, RA Wang, ZG Hsiao, BS AF Lincoln, DM Vaia, RA Wang, ZG Hsiao, BS TI Secondary structure and elevated temperature crystallite morphology of nylon-6/layered silicate nanocomposites SO POLYMER LA English DT Article DE nylon-6/layered silicate nanocomposites; mesoscale structure; crystallite morphology ID NYLON 6-CLAY HYBRID; X-RAY-SCATTERING; MODIFIED LAYERED SILICATES; LAMELLAR 2-PHASE SYSTEMS; MECHANICAL-PROPERTIES; CLAY NANOCOMPOSITES; MELT-INTERCALATION; POLYMER BRUSHES; ANGLE; POLYSTYRENE AB Mesoscale (secondary) structure arising from association of layered silicates is quantified and its impact, along with constituent interactions, on elevated temperature crystallite morphology in nylon-6/montmorillonite nanocomposites is examined. Simultaneous small- and wide-angle X-ray scattering and diffraction methods are developed to provide detailed information on the secondary structure of the layered silicate and the structure of the crystalline polymer in the presence of the layered silicate. Ultra-long range order (20-60 nm) of the inorganic layers is observed at low-volume fractions (0.8 vol%). Elevated temperature (205 degreesC) crystallite morphology of the nylon-6 matrix depends on the secondary structure and interfacial interactions. Smaller, more disordered lamellae are observed in the in situ polymerized nanocomposites whereas larger, more ordered lamellae are observed in melt-processed nanocomposites. (C) 2000 Elsevier Science Ltd. AU rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RP Vaia, RA (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RI Wang, Zhigang/F-6136-2010 NR 58 TC 266 Z9 285 U1 4 U2 28 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 FEB PY 2001 VL 42 IS 4 BP 1621 EP 1631 DI 10.1016/S0032-3861(00)00414-6 PG 11 WC Polymer Science SC Polymer Science GA 373RU UT WOS:000165303300035 ER PT J AU Jauchem, JR Ryan, KL Frei, MR Dusch, SJ Lehnert, HM Kovatch, RM AF Jauchem, JR Ryan, KL Frei, MR Dusch, SJ Lehnert, HM Kovatch, RM TI Repeated exposure of C3H/HeJ mice to ultra-wideband electromagnetic pulses: lack of effects on mammary tumors SO RADIATION RESEARCH LA English DT Article ID RADIOFREQUENCY RADIATION; MICROWAVE-RADIATION; BLOOD-PRESSURE; HEART-RATE; CANCER; LEVEL; PRONE; PROPAGATION AB It has been suggested that chronic, low-level exposure to radiofrequency (RF) radiation may promote the formation of tumors. Previous studies, however, showed that low-level, longterm exposure of mammary tumor-prone mice to 435 MHz or 2450 MHz RF radiation did not affect the incidence of mammary tumors. In this study, we investigated the effects of exposure to a unique type of electromagnetic energy: pulses composed of an ultra-wideband (UWB) of frequencies, including those in the RF range. One hundred C3H/HeJ mice were exposed to UWB pulses (rise time 176 ps, fall time 3.5 ns, pulse width 1.9 ns, peak E-field 40 kV/m, repetition rate 1 kHz). Each animal was exposed for 2 min once a week for 12 weeks. One hundred mice were used as sham controls. There were no significant differences between groups with respect to incidence of palpated mammary tumors, latency to tumor onset, rate of tumor growth, or animal survival. Histopathological evaluations revealed no significant differences between the two groups in numbers of neoplasms in all tissues studied (lymphoreticular tissue, thymus, respiratory, digestive and urinary tracts, reproductive, mammary and endocrine systems, and skin). Our major finding was the lack of effects of UWB-pulse exposure on promotion of mammary tumors in a well-established animal model of mammary cancer. (C) 2001 by Radiation Research Society. C1 USAF, Res Lab, Radio Frequency Radiat Branch, Directed Energy Bioeffects Div,HEDR, Brooks AFB, TX 78235 USA. Pathol Associates Int, Frederick, MD USA. Trinity Univ, Dept Biol, San Antonio, TX 78212 USA. RP Jauchem, JR (reprint author), USAF, Res Lab, Radio Frequency Radiat Branch, Directed Energy Bioeffects Div,HEDR, 8315 Hawks Rd, Brooks AFB, TX 78235 USA. NR 44 TC 19 Z9 21 U1 0 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD FEB PY 2001 VL 155 IS 2 BP 369 EP 377 DI 10.1667/0033-7587(2001)155[0369:REOCHM]2.0.CO;2 PG 9 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 397RF UT WOS:000166708800013 PM 11175673 ER PT J AU Parnell, GS Frimpon, M Barnes, J Kloeber, JM Deckro, RF Jackson, JA AF Parnell, GS Frimpon, M Barnes, J Kloeber, JM Deckro, RF Jackson, JA TI Safety risk analysis of an innovative environmental technology SO RISK ANALYSIS LA English DT Article DE risk analysis; decision analysis; CERCLA; superfund; environmental remediation; nuclear waste; innovative technologies AB The authors describe a decision and risk analysis performed for the cleanup of a large Department of Energy mixed-waste subsurface disposal area governed by the Comprehensive Environmental Response, Compensation. and Liability Act (CERCLA). In a previous study, the authors worked with the site decision makers, state regulators, and U.S. Environmental Protection Agency regional regulators to develop a CERCLA-based multiobjective decision analysis value model and used the model to perform a screening analysis of 28 remedial alternatives. The analysis results identified an innovative technology, in situ vitrification, with high effectiveness versus cost. Since this technology had not been used on this scale before, the major uncertainties were contaminant migration and pressure buildup. Pressure buildup was a safety concern due to the potential risks to worker safety. With the help of environmental technology experts remedial alternative changes were identified to mitigate the concerns about contaminant migration and pressure buildup. The analysis results showed that the probability of an event with a risk to worker safety had been significantly reduced. Based on these results, site decision makers have refocused their test program to examine in situ vitrification and have continued the use of the CERCLA-based decision analysis methodology to analyze remedial alternatives. C1 US Mil Acad, Dept Syst Engn, W Point, NY 10996 USA. Toffler Associates, Manchester, MA USA. Virginia Commonwealth Univ, Dept Math Sci, Richmond, VA 23284 USA. USAF, Inst Technol, Ctr Modeling Simulat & Anal, Wright Patterson AFB, OH 45433 USA. RP Parnell, GS (reprint author), US Mil Acad, Dept Syst Engn, W Point, NY 10996 USA. NR 14 TC 12 Z9 13 U1 4 U2 5 PU BLACKWELL PUBL LTD PI OXFORD PA 108 COWLEY RD, OXFORD OX4 1JF, OXON, ENGLAND SN 0272-4332 J9 RISK ANAL JI Risk Anal. PD FEB PY 2001 VL 21 IS 1 BP 143 EP 155 DI 10.1111/0272-4332.211097 PG 13 WC Public, Environmental & Occupational Health; Mathematics, Interdisciplinary Applications; Social Sciences, Mathematical Methods SC Public, Environmental & Occupational Health; Mathematics; Mathematical Methods In Social Sciences GA 424BY UT WOS:000168213300013 PM 11332543 ER PT J AU McQuay, WK AF McQuay, WK TI Distributed collaborative environments for 21st century modeling & simulation SO SIMULATION LA English DT Article C1 USAF, RL, IFSD, Wright Patterson AFB, OH 45433 USA. RP McQuay, WK (reprint author), USAF, RL, IFSD, 2241 Avion Circle,Rm S1Z19, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 3 U1 0 U2 0 PU SIMULATION COUNCILS INC PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92117 USA SN 0037-5497 J9 SIMULATION JI Simulation PD FEB PY 2001 VL 76 IS 2 BP 94 EP 95 DI 10.1177/003754970107600210 PG 2 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering SC Computer Science GA 434MG UT WOS:000168819000010 ER PT J AU Beninati, W Sanders, MH AF Beninati, W Sanders, MH TI Optimal continuous positive airway pressure for the treatment of obstructive sleep apnea/hypopnea SO SLEEP MEDICINE REVIEWS LA English DT Review DE obstructive sleep; apnea-hypopnea syndrome; continuous positive airway; pressure; polysomnogram ID EXCESSIVE DAYTIME SLEEPINESS; SPLIT-NIGHT POLYSOMNOGRAPHY; APNEA SYNDROME PATIENTS; CPAP THERAPY; APNOEA/HYPOPNOEA SYNDROME; FLOW LIMITATION; NASAL CPAP; AUTO-CPAP; TITRATION; MASK AB The obstructive sleep apnea/hypopnea syndrome (OSA/H) is characterised by repetitive obstruction of the upper airway during sleep. The consequences of OSA/H include excessive daytime sleepiness, reduced perceived health quality and an increased risk of driving accidents. There is evidence that treatment with nasal continuous positive airway pressure (CPAP) is effective in eliminating these consequences. In addition, OSA/H may also be associated with hypertension and an increased risk of vascular disease, acid although there is no clear evidence in this regard, CPAP may be effective alleviating these consequences as well. Nasal CPAP is considered the treatment of choice for clinically significant OSA/H. The optimal CPAP prescription is that which is most effective in eliminating the adverse consequences of OSA/H. Patients should be initially treated with standard CPAP. For those in whom standard CPAP is unsuccessful or intolerable bi-level or self-adjusting modes may be attempted. The nasal CPAP pressure level can be titrated to eliminate apnea, hypopnea, snoring, respiratory arousal and inspiratory flow limitation as a means of predicting successful long-term therapy. The reliability of these physiologic parameters in predicting the optimal long-term CPAP pressure is eroded by the tendency of CPAP pressure-level requirement to decrease with chronic CPAP use, and by other factors that may increase the CPAP pressure requirement. The split-night polysomnogram and unattended auto-CPAP titration have been proposed as efficient means of determining the optimal CPAP pressure, but for patients with subtle OSA/H, underlying cardiopulmonary disease or other forms of sleep-disordered breathing a full-night polysomnogram may be required. The CPAP prescription must include a comfortable well-fitting interface. When CPAP is prescribed it is essential that the patient undergo clinical re-evaluation to ensure that treatment goals are being met. (C) 2001 Harcourt Publishers Ltd. C1 Wilford Hall USAF Med Ctr, Pulm Crit Care Med Div, Lackland AFB, TX 78236 USA. Univ Pittsburgh, Div Pulm Allergy & Crit Care Med, Vet Affairs Hlth Care Syst Pittsburgh, Pulm Sleep Disorders Program,Pulm Serv, Pittsburgh, PA 15260 USA. Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA. RP Beninati, W (reprint author), Wilford Hall USAF Med Ctr, Pulm Crit Care Med Div, 2200 Berquist Dr, Lackland AFB, TX 78236 USA. NR 69 TC 12 Z9 12 U1 0 U2 1 PU W B SAUNDERS CO LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 1087-0792 J9 SLEEP MED REV JI Sleep Med. Rev. PD FEB PY 2001 VL 5 IS 1 BP 7 EP 23 DI 10.1053/smrv.2000.0131 PG 17 WC Clinical Neurology; Neurosciences SC Neurosciences & Neurology GA 406AD UT WOS:000167192000003 ER PT J AU Cocks, FH Watkins, SA Walker, MJ Lutz, TA Sussingham, JC AF Cocks, FH Watkins, SA Walker, MJ Lutz, TA Sussingham, JC TI A high-resolution solar telescope using dark-lens diffractive optics SO SOLAR PHYSICS LA English DT Article ID OPAQUE SPHERE; MISSION; LIGHT AB A telescope based upon dark-lens diffractive optics would be a uniquely new instrument for solar astronomy. The image formation process in such a telescope gives an intrinsically higher resolving power and a greatly reduced image intensity compared tit that of refracting or reflecting optical systems of similar lens dimension. This low image intensity would be an advantage for solar observations made using a very large imaging element. After a brief overview of the history of solar instrument development, a quantitative evaluation of the dark-lens diffracting solar telescope concept is presented, showing the potential of this imaging method to meet or even to exceed the most demanding resolution goals currently being considered for future space-borne solar telescopes. C1 Duke Univ, Sch Engn, Durham, NC 27708 USA. USAF, Ogden Air Logist Ctr, Hill AFB, UT 84056 USA. RP Cocks, FH (reprint author), Duke Univ, Sch Engn, Durham, NC 27708 USA. NR 40 TC 0 Z9 0 U1 2 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD FEB PY 2001 VL 198 IS 2 BP 211 EP 222 DI 10.1023/A:1005221126857 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 427AM UT WOS:000168382700001 ER PT J AU Gidvani, VK Tyree, MM Bhowmick, SK AF Gidvani, VK Tyree, MM Bhowmick, SK TI Castleman's disease: Atypical manifestation in an 11-year-old girl SO SOUTHERN MEDICAL JOURNAL LA English DT Article ID LYMPH-NODE HYPERPLASIA; HYALINE VASCULAR TYPE; SYSTEMIC MANIFESTATIONS AB Castleman's disease (angiofollicular lymphoid hyperplasia) is a rare lymphoproliferative disorder that can be found in both nodal and extranodal sites, It is classified histologically as the more common hyaline vascular variant, a plasma cell variant, or a mixed form. The hyaline vascular variant is typically characterized by a benign clinical course with no constitutional symptoms other than localized pressure from the mass. We report an atypical case of the hyaline vascular variant with constitutional symptoms that have been clinically associated with the aggressive plasma cell variant. Diagnosis was confirmed histopathologically after surgical resection, which was curative and resulted in resolution of all symptoms. This case broadens our understanding of Castleman's disease as a part of the Spectrum of lymphoproliferative and inflammatory diseases. Furthermore, it supports recent studies suggesting that systemic pathogenicity is related to associated cytokine dysregulation and highlights the need to include Castleman's disease in the differential diagnosis of pediatric lymphoproliferative disorders. C1 Dept Pediat, Keesler AFB, MS USA. RP Tyree, MM (reprint author), SGOC, Med Grp 81, 301 Fisher St,Room 1A132, Keesler AFB, MS 39531 USA. NR 13 TC 9 Z9 10 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 FEB PY 2001 VL 94 IS 2 BP 250 EP 253 PG 4 WC Medicine, General & Internal SC General & Internal Medicine GA 406CH UT WOS:000167197000017 PM 11235046 ER PT J AU Hedrick, A AF Hedrick, A TI Using unorthodox training methods to achieve superior results SO STRENGTH AND CONDITIONING JOURNAL LA English DT Editorial Material DE determining training weight; straps; trunk training; speed-strength; dumbells; manual resistence; dynamic stretching C1 USAF Acad, Colorado Springs, CO 80840 USA. RP Hedrick, A (reprint author), USAF Acad, Colorado Springs, CO 80840 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ALLEN PRESS INC PI LAWRENCE PA 810 E 10TH ST, LAWRENCE, KS 66044 USA SN 1073-6840 J9 STRENGTH COND J JI Strength Cond. J. PD FEB PY 2001 VL 23 IS 1 BP 62 EP 65 PG 4 WC Sport Sciences SC Sport Sciences GA 401BV UT WOS:000166907800015 ER PT J AU Chen, MY Kramer, DJ AF Chen, MY Kramer, DJ TI Properties of carbon nitride films deposited with and without electron cyclotron resonance plasma assistance SO THIN SOLID FILMS LA English DT Article DE carbon nitride films; electron cyclotron resonance plasma; friction; hardness ID RAY PHOTOELECTRON-SPECTROSCOPY; THIN-FILMS; ION-BEAM; LASER-ABLATION; GRAPHITE; DIAMOND; SOLIDS; RAMAN; RATIO AB Research on carbon nitride has received considerable attention since beta -C3N4 offers high technological potential for protective, wear, and optical applications. Deposition of carbon nitride by various techniques has mostly resulted in nitrogen deficient amorphous CN, films. In this research, reactive magnetron sputtering with and without the assistance of an electron cyclotron resonance (ECR) source was used to deposit CN, thin films at ambient temperature. The process variables include power level, nitrogen partial pressure, and substrate bias. X-Ray photoelectron spectroscopy and Auger analysis were used to determine the composition and chemical bonding of the films. Ball-on-disc experiments were performed between 440C stainless steel balls and CNx-coated 440C substrates at 0.1 m/s sliding velocity and 1 N load. The effects of process variables and interface modification on friction and wear rate were examined. Mechanical properties including hardness, modulus, and elastic response were obtained from nanoindentation. CN, films with hardness in the range of 12-16 GPa demonstrated better wear performance than the hardest diamond-like carbon (24 GPa) deposited by the same technique. ECR assisted magnetron sputtering provided films with the lowest wear rates. (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, AFRL,MLBT, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, AFRL,MLBT, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. EM mingchen@wpafb.af.mil NR 28 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD FEB 1 PY 2001 VL 382 IS 1-2 BP 4 EP 12 DI 10.1016/S0040-6090(00)01779-X PG 9 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 407JP UT WOS:000167268700002 ER PT J AU Pillard, DA Cornell, JS Dufresne, DL Hernandez, MT AF Pillard, DA Cornell, JS Dufresne, DL Hernandez, MT TI Toxicity of benzotriazole and benzotriazole derivatives to three aquatic species SO WATER RESEARCH LA English DT Article DE benzotriazole; deicers; glycol; toxicity ID INTERNATIONAL AIRPORT; WATER AB Benzotriazole and its derivatives comprise an important class of corrosion inhibitors, typically used as trace additives in industrial chemical mixtures such as coolants, deicers, surface coatings, cutting fluids, and hydraulic fluids. Recent studies have shown that benzotriazole derivatives are a major component of aircraft deicing fluids (ADFs) responsible for toxicity to bacteria (Microtox(R)). Our current research compared the toxicity of benzotriazole (BT), two methylbenzotriazole (MeBT) isomers, and butylbenzotriazole (BBT). Acute toxicity assays were used to model the response of three common test organisms: Microtox(R) bacteria (Vibrio f ischeri), fathead minnow (Pimephales promelas) and water flea (Ceriodaphnia dubia). The response of all the three organisms varied over two orders of magnitude among all compounds. Vibrio fischeri was more sensitive than either C. dubia or P. promelas to all the test materials, while C. dubia was less sensitive than P. promelas. The response of test organisms to unmethylated benzotriazole and 4-methytbenzotriazole was similar, whereas 5-methylbenzotriazole was more toxic than either of these two compounds. BET was the most toxic benzotriazole derivative tested, inducing acute toxicity at a concentration of less than or equal to 3.3 mg/l to all organisms. (C) 2000 Elsevier Science Ltd. All rights reserved C1 ENSR, Ft Collins, CO 80521 USA. USAF, Ctr Environm Excellence, HQ AFCEE ERT, Brooks AFB, TX 78235 USA. Univ Colorado, Dept Civil Environm & Architectural Engn, Boulder, CO 80309 USA. RP Pillard, DA (reprint author), ENSR, 4303 W LaPorte Ave, Ft Collins, CO 80521 USA. NR 10 TC 90 Z9 95 U1 8 U2 43 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0043-1354 J9 WATER RES JI Water Res. PD FEB PY 2001 VL 35 IS 2 BP 557 EP 560 DI 10.1016/S0043-1354(00)00268-2 PG 4 WC Engineering, Environmental; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA 393KA UT WOS:000166466700027 PM 11229011 ER PT J AU Vij, A Zhang, XZ Christe, KO AF Vij, A Zhang, XZ Christe, KO TI Crystal structure of F2NO+AsF6- and method for extracting meaningful geometries from oxygen/fluorine disordered crystal structures SO INORGANIC CHEMISTRY LA English DT Article AB A method is outlined for extracting meaningful geometries from certain oxygen/fluorine disordered crystal structures. The validity of the approach is demonstrated for F2NO+AsF6-. C1 USAF, Res Lab, Propuls Sci & Adv Concepts Div, Edwards AFB, CA 93524 USA. Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. RP Christe, KO (reprint author), USAF, Res Lab, Propuls Sci & Adv Concepts Div, Edwards AFB, CA 93524 USA. RI Vij, Ashwani/A-2836-2012; Christe, Karl/O-4885-2014 OI Vij, Ashwani/0000-0003-1144-4080; Christe, Karl/0000-0003-0661-5519 NR 3 TC 8 Z9 8 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD JAN 29 PY 2001 VL 40 IS 3 BP 416 EP + DI 10.1021/ic0007613 PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 396ZZ UT WOS:000166669400001 PM 11209595 ER PT J AU Friedman, L Sun, G Soref, RA AF Friedman, L Sun, G Soref, RA TI SiGe/Si THz laser based on transitions between inverted mass light-hole and heavy-hole subbands SO APPLIED PHYSICS LETTERS LA English DT Article ID INTERSUBBAND LASERS; SILICON AB We have investigated a SiGe/Si quantum-well laser based on transitions between the light-hole and heavy-hole subbands. The lasing occurs in the region of k space where the dispersion of ground-state light-hole subband is so nonparabolic that its effective mass is inverted. This kind of lasing mechanism makes total population inversion between the two subbands unnecessary. The laser structure can be electrically pumped through tunneling in a quantum cascade scheme. Optical gain as high as 172/cm at the wavelength of 50 mum can be achieved at the temperature of liquid nitrogen, even when the population of the upper laser subband is 15% less than that of the lower subband. (C) 2001 American Institute of Physics. 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 13 TC 50 Z9 54 U1 1 U2 10 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 22 PY 2001 VL 78 IS 4 BP 401 EP 403 DI 10.1063/1.1341221 PG 3 WC Physics, Applied SC Physics GA 393NV UT WOS:000166477300004 ER PT J AU Semiatin, SL Berbon, PB Langdon, TG AF Semiatin, SL Berbon, PB Langdon, TG TI Deformation heating and its effect on grain size evolution during equal channel angular extrusion SO SCRIPTA MATERIALIA LA English DT Article DE equal channel angular extrusion; cold working; deformation heating; grain size ID TEMPERATURES; ALUMINUM C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLLM, Wright Patterson AFB, OH 45433 USA. Rockwell Int Sci Ctr, Thousand Oaks, CA 91360 USA. Univ So Calif, Dept Mat Sci, Los Angeles, CA 90089 USA. Univ So Calif, Dept Engn Mech, Los Angeles, CA 90089 USA. RP Semiatin, SL (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLLM, 2230 10th St, Wright Patterson AFB, OH 45433 USA. RI Langdon, Terence/B-1487-2008; SEMIATIN, SHELDON/E-7264-2017 NR 26 TC 54 Z9 57 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD JAN 19 PY 2001 VL 44 IS 1 BP 135 EP 140 DI 10.1016/S1359-6462(00)00565-0 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 399JP UT WOS:000166808100022 ER PT J AU Kessler, C Kim, J AF Kessler, C Kim, J TI Concept of directional natural mode for vibration analysis of rotors using complex variable descriptions SO JOURNAL OF SOUND AND VIBRATION LA English DT Letter ID FREQUENCY-RESPONSE FUNCTIONS; ROTATING MACHINERY C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Univ Cincinnati, Struct Dynam Res Lab, Cincinnati, OH 45221 USA. RP Kessler, C (reprint author), USAF, Res Lab, AFRL PRPG Bldg 18A Rm 231,1950 5th st, Wright Patterson AFB, OH 45433 USA. NR 10 TC 2 Z9 2 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD JAN 18 PY 2001 VL 239 IS 3 BP 545 EP 555 DI 10.1006/jsvi.2000.3063 PG 11 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA 397FG UT WOS:000166682200011 ER PT J AU O'Brien, KE O'Bryan, CL Saad, R AF O'Brien, KE O'Bryan, CL Saad, R TI Predictors of outcome in asymptomatic aortic stenosis. SO NEW ENGLAND JOURNAL OF MEDICINE LA English DT Letter C1 Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP O'Brien, KE (reprint author), Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. NR 2 TC 1 Z9 1 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 JAN 18 PY 2001 VL 344 IS 3 BP 227 EP 228 PG 2 WC Medicine, General & Internal SC General & Internal Medicine GA 392GF UT WOS:000166402800013 PM 11188838 ER PT J AU Prasad, YVRK Seshacharyulu, T Medeiros, SC Frazier, WG AF Prasad, YVRK Seshacharyulu, T Medeiros, SC Frazier, WG TI Influence of oxygen content on the forging response of equiaxed (alpha+beta) preform of Ti-6Al-4V: commercial vs. ELI grade SO JOURNAL OF MATERIALS PROCESSING TECHNOLOGY LA English DT Article DE Ti-6Al-4V; equiaxed preform; hot working; microstructural control; oxygen effect; processing maps ID DEFORMATION AB The hot deformation characteristics of equiaxed (alpha + beta) preform of Ti-6Al-4V have been evaluated in two oxygen grades viz., commercial grade and extra-low interstitial (ELI) grade. Constant strain rate hot compression tests were conducted on cylindrical specimens in the temperature range 750-1100 degreesC and strain rate range 10(-3)-100 s(-1) up to a true strain of about 0.5. The shapes of stress-strain curves in the alpha-beta region and beta -region, the kinetic parameters, and the processing maps obtained on the two grades have been compared with a view to evaluate the effect of oxygen on the processing of Ti-6Al-4V with equiaxed (alpha + beta) preform. The shapes of the stress-strain curves are similar in the two oxygen grades although the Row stress of the commercial grade is slightly higher than that of the ELI grade. While the values of the stress exponent are similar in both grades, the apparent activation energy for hot deformation of commercial grade is higher than that of the ELI grade in bath alpha-beta and beta ranges. The processing maps revealed that superplasticity occurs in the alpha-beta range while dynamic recrystallization (DRX) occurs in the beta range. In the commercial grade, the superplasticity domain is spread over a wider temperature range and occurs at lower strain rates than that in the ELI grade. On the other hand, the ductility peak in the ELI grade is narrow and may require closer temperature control during processing. The DRY of beta occurs at 1100 degreesC in both grades but at a higher strain rate in the commercial grade than in the ELI grade. Unlike the commercial grade, deformation of the ELI grade close to the beta transus has to he avoided since a possibility of void nucleation or wedge crack formation exists at slow strain rates. Both grades exhibit flow instabilities manifested as adiabatic shear bands and flow localization when deformed at strain rates higher than about l s(-1). (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Res Lab, MLMR, Mat Proc Design Branch, Wright Patterson AFB, OH 45433 USA. RP Frazier, WG (reprint author), USAF, Res Lab, MLMR, Mat Proc Design Branch, Wright Patterson AFB, OH 45433 USA. NR 15 TC 47 Z9 55 U1 1 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-0136 J9 J MATER PROCESS TECH JI J. Mater. Process. Technol. PD JAN 17 PY 2001 VL 108 IS 3 BP 320 EP 327 DI 10.1016/S0924-0136(00)00832-3 PG 8 WC Engineering, Industrial; Engineering, Manufacturing; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 394PL UT WOS:000166532400008 ER PT J AU Fang, ZQ Look, DC Jasinski, J Benamara, M Liliental-Weber, Z Molnar, RJ AF Fang, ZQ Look, DC Jasinski, J Benamara, M Liliental-Weber, Z Molnar, RJ TI Evolution of deep centers in GaN grown by hydride vapor phase epitaxy SO APPLIED PHYSICS LETTERS LA English DT Article ID STOICHIOMETRY; DISLOCATION AB Deep centers and dislocation densities in undoped n GaN, grown by hydride vapor phase epitaxy (HVPE), were characterized as a function of the layer thickness by deep level transient spectroscopy and transmission electron microscopy, respectively. As the layer thickness decreases, the variety and concentration of deep centers increase, in conjunction with the increase of dislocation density. Based on comparison with electron-irradiation induced centers, some dominant centers in HVPE GaN are identified as possible point defects. (C) 2001 American Institute of Physics. C1 Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Lincoln Lab, Lexington, MA 02173 USA. USAF, Mat & Mfg Directorate, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Fang, ZQ (reprint author), Wright State Univ, Semicond Res Ctr, Dayton, OH 45435 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 15 TC 81 Z9 81 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JAN 15 PY 2001 VL 78 IS 3 BP 332 EP 334 DI 10.1063/1.1338970 PG 3 WC Physics, Applied SC Physics GA 389YY UT WOS:000166267300025 ER PT J AU Sylvia, VL Schwartz, Z Del Toro, F DeVeau, P Whetstone, R Hardin, RR Dean, DD Boyan, BD AF Sylvia, VL Schwartz, Z Del Toro, F DeVeau, P Whetstone, R Hardin, RR Dean, DD Boyan, BD TI Regulation of phospholipase D (PLD) in growth plate chondrocytes by 24R,25-(OH)(2)D-3 is dependent on cell maturation state (resting zone cells) and is specific to the PLD2 isoform SO BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH LA English DT Article DE chondrocyte culture; phospholipase D; 24R,25-dihydroxycholecalciferol; protein kinase C; alkaline phosphatase; signal transduction; cell maturation ID PROTEIN-KINASE-C; ADP-RIBOSYLATION-FACTOR; VITAMIN-D METABOLITES; ARACHIDONIC-ACID TURNOVER; MEMBRANE-RECEPTOR; RAT-BRAIN; PHOSPHATIDYLINOSITOL 3-KINASE; NONGENOMIC REGULATION; D ACTIVATION; MECHANISMS AB Many of the effects of 1 alpha ,25-(OH)(2)D-3 and 24R,25-(OH)(2)D-3 on costochondral chondrocytes are mediated by the protein kinase C (PKC) signal transduction pathway. 1 alpha ,25-(OH)(2)D-3 activates PKC in costochondral growth zone chondrocytes through a specific membrane receptor (1 alpha ,25-mVDR), involving rapid increases in diacylglycerol via a phospholipase C (PLC)-dependent mechanism. 24R,25-(OH)(2)D-3 activates PKC in resting zone chondrocytes. Although diacylglycerol is increased by 24R,25-(OH)(2)D-3, PLC is not involved, suggesting a phospholipase D (PLD)-dependent mechanism. Here, we show that resting zone and growth zone cells express mRNAs for PLD1a, PLD1b, and PLD2. Both cell types have PLD activity, but levels are higher in resting zone cells. 24R,25-(OH)(2)D-3, but not 24S,25-(OH)(2)D-3 or 1 alpha ,25-(OH)(2)D-3, stimulates PLD activity in resting zone cells within 3 min via nongenomic mechanisms. Neither la,25-(OH)(2)D-3 nor 24R,25-(OH)(2)D-3 affected PLD in growth zone cells. Basal and 24R,25-(OH)(2)D-3-stimulated PLD were inhibited by the PLD inhibitors wortmannin and EDS. Inhibition of phosphatidylinositol S-kinase (PI 3-kinase), PKC, phosphatidylinositol-specific PLC (PI-PLC), and phosphatidylcholine-specific PLC (PC-PLC) had no effect on PLD activity. Thus, 24R,25-(OH)(2)D-3 stimulates PLD, and PI 3-kinase, PI-PLC and PKC are not involved, whereas PLD is required for stimulation of PKC by 24R,25(OH)(2)D-3 Pertussis toxin, GDP betaS, and GTP gammaS had no effect on 24R,25-(OH)(2)D-3-dependent PLD when added to cell cultures, indicating that G-proteins are not involved. These data show that PKC activation in resting zone cells is mediated by PLD and suggest that a functional 24R,25-(OH)(2)D-3-mVDR is required. The results also support the conclusion that the 24R,25-(OH)(2)D-3-responsive PLD is PLD2, since this PLD isoform is G-protein-independent. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Texas, Hlth Sci Ctr, Dept Orthopaed, San Antonio, TX 78229 USA. Univ Texas, Hlth Sci Ctr, Dept Periodont, San Antonio, TX 78229 USA. Hebrew Univ Jerusalem, Fac Med Dent, Dept Periodont, IL-91010 Jerusalem, Israel. Univ Texas, Hlth Sci Ctr, Dept Orthodont, San Antonio, TX 78229 USA. Wilford Hall USAF Med Ctr, Dept Periodont, San Antonio, TX 78236 USA. Univ Texas, Hlth Sci Ctr, Dept Biochem, San Antonio, TX 78229 USA. RP Univ Texas, Hlth Sci Ctr, Dept Orthopaed, Mail Code 7774,7703 Floyd Curl Dr, San Antonio, TX 78229 USA. EM boyanb@uthscsa.edu FU NIDCR NIH HHS [DE-08603, DE-05937] NR 61 TC 26 Z9 27 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-4889 EI 0006-3002 J9 BBA-MOL CELL RES JI Biochim. Biophys. Acta-Mol. Cell Res. PD JAN 15 PY 2001 VL 1499 IS 3 BP 209 EP 221 DI 10.1016/S0167-4889(00)00120-8 PG 13 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 396QN UT WOS:000166648200005 PM 11341968 ER PT J AU Kayasit, P Joshi, RP Islam, NE Schamiloglu, E Gaudet, J AF Kayasit, P Joshi, RP Islam, NE Schamiloglu, E Gaudet, J TI Transient and steady state simulations of internal temperature profiles in high-power semi-insulating GaAs photoconductive switches SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SEMICONDUCTOR SWITCHES; CURRENT FILAMENTS; GALLIUM-ARSENIDE; HIGH-VOLTAGE; RELAXATION SEMICONDUCTORS; LOCK-ON; MODEL; IONIZATION; DEVICES; GROWTH AB Simulations have been performed to determine the internal temperature profiles of high-power GaAs photoconductive switches in the presence of a current filament. No thermal instability is predicted below a power generation density level of about 1.3x10(14) W/m(3). This prediction is in keeping with recent experimental data on photoconductive semiconductor switch devices. It is shown that this power dissipation density threshold for stability exists under both dc and transient conditions. A simple model provides qualitative support for the power density threshold, and an explanation of the filamentary current radii that have been observed experimentally. (C) 2001 American Institute of Physics. C1 Old Dominion Univ, Dept Elect & Comp Engn, Norfolk, VA 23529 USA. Univ New Mexico, Dept Elect & Comp Engn, Albuquerque, NM 87131 USA. USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Kayasit, P (reprint author), Old Dominion Univ, Dept Elect & Comp Engn, Norfolk, VA 23529 USA. NR 49 TC 5 Z9 9 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JAN 15 PY 2001 VL 89 IS 2 BP 1411 EP 1417 DI 10.1063/1.1335824 PG 7 WC Physics, Applied SC Physics GA 387WG UT WOS:000166144400083 ER PT J AU Ruckstuhl, AF Jacobson, MP Field, RW Dodd, JA AF Ruckstuhl, AF Jacobson, MP Field, RW Dodd, JA TI Baseline subtraction using robust local regression estimation SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE baseline removal; LOWESS; robust fitting; smoothing ID FT NMR-SPECTRA; BACKGROUND SUBTRACTION; LINE CORRECTION; SPECTROSCOPY; ALGORITHM AB A technique entitled robust baseline estimation is introduced, which uses techniques of robust local regression to estimate baselines in spectra that consist of sharp features superimposed upon a continuous, slowly varying baseline. The technique is applied to synthetic spectra, to evaluate its capabilities, and to laser-induced fluorescence spectra of OH (produced from the reaction of ozone with hydrogen atoms). The latter example is a particularly challenging case for baseline estimation because the experimental noise Varies as a function of frequency. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Zurich Univ Appl Sci, Zucher Hsch Winterthur, Dept P, CH-8401 Winterthur, Switzerland. MIT, Dept Chem, Cambridge, MA 02139 USA. MIT, GR Harrison Spect Lab, Cambridge, MA 02139 USA. USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Ruckstuhl, AF (reprint author), Zurich Univ Appl Sci, Zucher Hsch Winterthur, Dept P, Postfach 805, CH-8401 Winterthur, Switzerland. OI Jacobson, Matthew/0000-0001-6262-655X NR 22 TC 63 Z9 71 U1 3 U2 20 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 JAN 15 PY 2001 VL 68 IS 2 BP 179 EP 193 DI 10.1016/S0022-4073(00)00021-2 PG 15 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 364ZF UT WOS:000089923400004 ER PT J AU Leedy, KD Stubbins, JF AF Leedy, KD Stubbins, JF TI Copper alloy-stainless steel bonded laminates for fusion reactor applications: tensile strength and microstructure SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE copper; microstructure; tensile strength; CuNiBe; Cu-Al2O3; stainless steel AB The tensile strength of copper alloy-stainless steel bi-layer panels joined by hot isostatic pressing or explosive bonding was tested over a temperature range 25-350 degreesC. The bonding processes caused changes in interfacial microstructures which affected the interfacial mechanical properties. Hot isostatic pressed materials studied included: precipitation strengthened CuNiBe or dispersion strengthened Cu-Al2O3 bonded to 316L stainless steel plates and Cu-Al2O3 bonded to Cu-Al2O3. An explosive bonded panel of Cu-Al2O3-316L stainless steel was also examined. Hot isostatic pressed panels showed similar decreasing shear strengths with increasing temperature, while the explosive bonded panel displayed substantially higher strength at 25 degreesC but declined rapidly as the test temperature increased. Tensile strengths of all panels were nominally lower than the constituent bulk material strengths and delamination near the copper ahoy-stainless steel interface was the dominate failure mode in the bi-metallic panels. The joining processes were found to alter the microstructure of the bond interfacial regions in the form of microporosity and Fe-Cr-B precipitate formation, NiBe precipitate morphology changes and interdiffusion of constituent elements. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Univ Illinois, Dept Nucl Engn, Urbana, IL 61801 USA. RP Leedy, KD (reprint author), USAF, Sensors Directorate, AFRL, SNDI, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 22 TC 16 Z9 20 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 15 PY 2001 VL 297 IS 1-2 BP 10 EP 18 DI 10.1016/S0921-5093(00)01273-9 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 389MG UT WOS:000166241400002 ER PT J AU Leedy, KD Stubbins, JF AF Leedy, KD Stubbins, JF TI Copper alloy-stainless steel bonded laminates for fusion reactor applications: crack growth and fatigue SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE copper; crack growth; fatigue; CuNiBe; Cu-Al2O3; stainless steer AB Fatigue and crack growth in copper alloy-stainless steel bi-layer panels joined by hot isostatic pressing or explosive bonding were tested over the temperature range 25-225 degreesC. Several material combinations under consideration for fusion reactor first wall applications were studied: solid plates of precipitation strengthened CuNiBe or dispersion strengthened CuAl2O3 bonded to a 316L stainless steel plate and Cu-Al2O3 in a powder form consolidated and bonded concurrently to a 316L stainless steel plate. Fatigue and crack growth were measured perpendicular to the interface through the copper alloy. Crack growth was also measured parallel to the interface along the bond line. The solid Cu-Al2O3-stainless steel laminate exhibited the best perpendicular crack growth resistance and fatigue performance of the bonded panels due primarily to the elongated Cu-Al2O3 grains oriented perpendicular to the crack propagation direction. Before reaching the interface cracks propagating perpendicular to the interface caused delamination in most panels near the copper alloy-stainless steel bond line within the copper alloy. All bi-layer panels displayed minimal resistance to parallel crack growth. (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Sensors Directorate, AFRL, SNDI, Wright Patterson AFB, OH 45433 USA. RP Leedy, KD (reprint author), USAF, Sensors Directorate, AFRL, SNDI, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 12 TC 15 Z9 15 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 15 PY 2001 VL 297 IS 1-2 BP 19 EP 25 DI 10.1016/S0921-5093(00)01274-0 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 389MG UT WOS:000166241400003 ER PT J AU Sankaran, KK Perez, R Jata, KV AF Sankaran, KK Perez, R Jata, KV TI Effects of pitting corrosion on the fatigue behavior of aluminum alloy 7075-T6: modeling and experimental studies SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE fatigue life prediction; corrosion fatigue; accelerated corrosion tests; pitting corrosion; corrosion metrics ID PREDICTION; 2024-T3; GROWTH AB The effects of pitting corrosion on the fatigue behavior of bare 7075-T6 aluminum alloy were investigated. Fitting corrosion decreased the fatigue lives by a factor of about 6 to 8. The fatigue lives were also calculated assuming an equivalent initial flaw corresponding to pits of average and maximum dimensions. The measured fatigue lives generally agreed with the predictions using the average rather than the maximum pit size as the initial crack size. This result could be explained by the pit size distributions offering a significantly larger population of pits near the average size. This work has demonstrated the promise of standardized spray tests for obtaining quantitative measures of corrosion that can be used as inputs in analytical models for fatigue life prediction for evaluating integrity of aircraft structures. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Boeing Co, St Louis, MO 63166 USA. USAF, Res Lab, Mat & Mfg Directorate, MLLM, Wright Patterson AFB, OH 45433 USA. RP Sankaran, KK (reprint author), Boeing Co, Mail Code S111 1041,POB 516, St Louis, MO 63166 USA. NR 11 TC 96 Z9 112 U1 1 U2 31 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JAN 15 PY 2001 VL 297 IS 1-2 BP 223 EP 229 DI 10.1016/S0921-5093(00)01216-8 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 389MG UT WOS:000166241400029 ER PT J AU Golovnin, IV Paraschuk, DY Pan, XY Chigarev, NV Knize, RJ Zhdanov, BV Kobryanskii, VM AF Golovnin, IV Paraschuk, DY Pan, XY Chigarev, NV Knize, RJ Zhdanov, BV Kobryanskii, VM TI Probing of the 2A(g) state in nanopolyacetylene on the time scale from femtoseconds to milliseconds SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 4th International Topical Conference on Optical Probes on Pi-Conjugated Polymers and Photonic Crystals CY FEB 15-19, 2000 CL SALT LAKE CITY, UTAH SP Univ Utah, Dept Energy, Univ Utah, Dept Phys, Honeywell, Elsevier, Los Alamos Natl Lab DE polyacetylene; photoinduced absorption spectroscopy; time-resolved spectroscopy; polarimetry ID GAP STATES; POLYACETYLENE; DYNAMICS AB The dynamic properties of the 2A(g) stare in films of nanopolyacetylene have been measured using photoinduced spectroscopy and photoinduced polarimetry methods both in the transient and cw regime. The excitation density per polyacetylene nanoparticle was no more than one absorbed pump photon. Using femtosecond pulses, we evaluated the rise time (less than or equal to0.2 ps) and the decay time (approximate to1 ps) of the photoinduced response from the 2A(g) state of ruans-nanopolyacetylene. The longest relaxation time approximate to7 mus was measured at room temperature. Using picosecond pulses and a novel photoinduced polarimetry method, we have done the first measurements of the transient polarization response of a conjugated material. The observed polarization signal is associated with a small photoinduced dichroism and birefringence in the 2A(g) state. The decay time of the polarization signal was approximate to0.3 ns. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Moscow MV Lomonosov State Univ, Dept Phys, Moscow 119899, Russia. USAF Acad, Dept Phys, Laser Opt & Res Ctr, Colorado Springs, CO 80840 USA. Russian Acad Sci, Inst Chem Phys, Moscow 117977, Russia. RP Golovnin, IV (reprint author), Moscow MV Lomonosov State Univ, Dept Phys, Moscow 119899, Russia. RI Kobryanskii, Valerii/M-3720-2015; Golovnin, Ilya/N-4187-2015; Paraschuk, Dmitry/H-4684-2011 OI Kobryanskii, Valerii/0000-0003-3613-8135; Paraschuk, Dmitry/0000-0002-9156-0657 NR 9 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN 15 PY 2001 VL 116 IS 1-3 BP 53 EP 56 DI 10.1016/S0379-6779(00)00514-2 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 393JL UT WOS:000166465400015 ER PT J AU McClain, MD Dudis, DS AF McClain, MD Dudis, DS TI Electronic and structural consequences of n-doping: bithiazole oligomers and partially reduced bithiazolium cations SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 4th International Topical Conference on Optical Probes on Pi-Conjugated Polymers and Photonic Crystals CY FEB 15-19, 2000 CL SALT LAKE CITY, UTAH SP Univ Utah, Dept Energy, Univ Utah, Dept Phys, Honeywell, Elsevier, Los Alamos Natl Lab DE semi-empirical; conducting polymer; n-doping; bithiazole; configuration; interaction ID PI-CONJUGATED POLYMERS; 5-MEMBERED RINGS; POLY(NONYLBITHIAZOLE); STACKING AB N-methylated-poly(diakyl-bithiazoles), NPABTs, can be reduced to give reasonably stable n-doped polymers. In order to understand the changes in the electronic structure and polymer conformations upon reductive doping of NPABTs, a series of oligomers of increasing length was studied by self-consistent field (AMI) and configuration interaction (ZINDO/S) calculations. Large red shifts in the optical transitions are predicted upon n-doping, along with significant planarization of chain segments. Full planarization was not realized for n-doped materials, however, as a variety of localized units were observed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Cedarville Univ, Dept Sci & Math, Cedarville, OH 45314 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP McClain, MD (reprint author), Cedarville Univ, Dept Sci & Math, Cedarville, OH 45314 USA. NR 19 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN 15 PY 2001 VL 116 IS 1-3 BP 199 EP 202 DI 10.1016/S0379-6779(00)00486-0 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 393JL UT WOS:000166465400045 ER PT J AU Das, GP Vaia, R Yeates, AT Dudis, DS AF Das, GP Vaia, R Yeates, AT Dudis, DS TI A theoretical model for excited state absorption SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 4th International Topical Conference on Optical Probes on Pi-Conjugated Polymers and Photonic Crystals CY FEB 15-19, 2000 CL SALT LAKE CITY, UTAH SP Univ Utah, Dept Energy, Univ Utah, Dept Phys, Honeywell, Elsevier, Los Alamos Natl Lab DE two-photon absorption; excited state absorption spectroscopy; transition probability ID 2-PHOTON ABSORPTION AB For long incident pulses, one-photon absorption in the excited stare formed following a two-photon absorption can play a very significant role in some organic materials. We develop here a quantitative model to determine the contribution of excited state absorption in the interpretation of the two-photon absorption data for such materials. We present representative calculations of this effect for some selected systems. (C) 2001 Elsevier Science B.V. All rights reserved. C1 MLBP, AFRL, Wright Patterson AFB, OH 45433 USA. RP Das, GP (reprint author), MLBP, AFRL, Wright Patterson AFB, OH 45433 USA. NR 8 TC 8 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN 15 PY 2001 VL 116 IS 1-3 BP 281 EP 283 DI 10.1016/S0379-6779(00)00467-7 PG 3 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 393JL UT WOS:000166465400060 ER PT J AU Duan, XF Dudis, DS Yeates, AT AF Duan, XF Dudis, DS Yeates, AT TI Electronic structure and energy band gap studies for poly(1,3-thienyl-squaraine) and its dianion SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 4th International Topical Conference on Optical Probes on Pi-Conjugated Polymers and Photonic Crystals CY FEB 15-19, 2000 CL SALT LAKE CITY, UTAH SP Univ Utah, Dept Energy, Univ Utah, Dept Phys, Honeywell, Elsevier, Los Alamos Natl Lab DE poly(1,3-thienyl-squaraine); oligomers; electron affinity ID CONDUCTING POLYMERS; POLYTHIOPHENE; SYSTEMS AB Poly(1,3-thienyl-squaraine) has been studied by means of semi-empirical and ab initio quantum theories. It has been found to have a very large electron affinity (>9 eV) and thus, would be unstable in the environment. The band gap of the polymer was found to be as low as 0.3-0.6 eV. A distinct transition from a zwitterionic to a quinoidal structure was observed in the progression of increasingly longer oligomers. (C) 2001 Published by Elsevier Science B.V. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLBP, Wright Patterson AFB, OH 45433 USA. RP Dudis, DS (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLBP, Bldg 654,2941 P St,Ste 1, Wright Patterson AFB, OH 45433 USA. NR 20 TC 3 Z9 3 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN 15 PY 2001 VL 116 IS 1-3 BP 285 EP 288 DI 10.1016/S0379-6779(00)00468-9 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 393JL UT WOS:000166465400061 ER PT J AU Yeates, AT Dudis, DS Connolly, JW AF Yeates, AT Dudis, DS Connolly, JW TI Triplet excitons in BBL SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 4th International Topical Conference on Optical Probes on Pi-Conjugated Polymers and Photonic Crystals CY FEB 15-19, 2000 CL SALT LAKE CITY, UTAH SP Univ Utah, Dept Energy, Univ Utah, Dept Phys, Honeywell, Elsevier, Los Alamos Natl Lab DE BBL; triplet state; conductivity; thermal excitations; excitons ID ELECTRICAL-CONDUCTIVITY; LADDER POLYMERS AB Electronic transitions in poly-benzimidazobenzophenanthroline (BBL) have been modelled by applying ab initio Hartree-Fock techniques to the ground and triplet states of various molecular analogues. We find that the triplet states are strongly localized to a single unit cell, leading to a Frenkel exciton picture of the excited state. (C) 2001 Published by Elsevier Science B.V. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLBP, Wright Patterson AFB, OH 45433 USA. Univ Missouri, Dept Chem, Kansas City, MO 64110 USA. RP Yeates, AT (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL,MLBP, 2941 P St,Ste 1, Wright Patterson AFB, OH 45433 USA. NR 17 TC 0 Z9 0 U1 3 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN 15 PY 2001 VL 116 IS 1-3 BP 289 EP 291 DI 10.1016/S0379-6779(00)00469-0 PG 3 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 393JL UT WOS:000166465400062 ER PT J AU Durstock, MF Taylor, B Spry, RJ Chiang, L Reulbach, S Heitfeld, K Baur, JW AF Durstock, MF Taylor, B Spry, RJ Chiang, L Reulbach, S Heitfeld, K Baur, JW TI Electrostatic self-assembly as a means to create organic photovoltaic devices SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT 4th International Topical Conference on Optical Probes on Pi-Conjugated Polymers and Photonic Crystals CY FEB 15-19, 2000 CL SALT LAKE CITY, UTAH SP Univ Utah, Dept Energy, Univ Utah, Dept Phys, Honeywell, Elsevier, Los Alamos Natl Lab DE photovoltaics; solar cells; self-assembly; charge transfer; poly(p-phenylene vinylene); fullerene ID DONOR-ACCEPTOR HETEROJUNCTIONS; SEMICONDUCTING POLYMERS; CONDUCTING-POLYMER; BUCKMINSTERFULLERENE; LUMINESCENCE; MULTILAYERS; PHOTODIODES; DIODES; CELLS AB Recently, there has been a significant amount of work done on making photovoltaic devices (solar cells) from thin films of conjugated polymers and other organic systems. The advantages over conventional inorganic systems include the potential to create lightweight, flexible, and inexpensive structures. The challenge, however, has been to create more highly efficient devices. To date, the primary photovoltaic device mechanism that has been utilized is that of photoinduced charge transfer between an electron donor and acceptor. In this study, similar photovoltaic devices are fabricated using a water-based electrostatic self-assembly procedure, as opposed to the more conventional spin-coating and/or vacuum evaporation techniques. In this process, layers of oppositely charged species are sequentially adsorbed onto a substrate from an aqueous solution and a film is built up due to the electrostatic attraction between the layers. The technique affords molecular level control over the architecture and gives bilayer thickness values of the order of tens of angstroms. By repeating this process a desired number of times and utilizing different cations and anions, complex architectures can be created with very accurate control over the thickness and the interfaces. We have examined a number of systems built from a variety of components including a cationic PPV precursor, functionalized Co,, and numerous other polyelectrolytes. We report on the device characteristics of these films and on the overall applicability of this technique to the fabrication of photovoltaic devices. Published by Elsevier Science B.V. C1 USAF, Res Lab, MLBP, Polymer Branch, Wright Patterson AFB, OH 45433 USA. Univ Dayton, Res Inst, Nonmet Mat Div, Dayton, OH 45469 USA. Natl Taiwan Univ, Taipei 10764, Taiwan. RP Durstock, MF (reprint author), USAF, Res Lab, MLBP, Polymer Branch, 2941 P St,Bldg 654, Wright Patterson AFB, OH 45433 USA. NR 19 TC 42 Z9 46 U1 1 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD JAN 15 PY 2001 VL 116 IS 1-3 BP 373 EP 377 DI 10.1016/S0379-6779(00)00440-9 PG 5 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 393JL UT WOS:000166465400079 ER PT J AU McHugh, CP AF McHugh, CP TI Garlic as a tick repellent SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Letter ID PERSONAL PROTECTION; INSECT REPELLENTS; PERMETHRIN; DEET; SAFETY; ACARI C1 USAF, Inst Environm Safety & Occupat Hlth Risk Anal, Brooks AFB, TX 78235 USA. RP McHugh, CP (reprint author), USAF, Inst Environm Safety & Occupat Hlth Risk Anal, Brooks AFB, TX 78235 USA. NR 6 TC 2 Z9 2 U1 0 U2 2 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD JAN 3 PY 2001 VL 285 IS 1 BP 41 EP 41 DI 10.1001/jama.285.1.41 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA 387GH UT WOS:000166114500015 PM 11150100 ER PT B AU Roeder, WP Vavrek, RJ Brody, FC Madura, JT Harms, DE AF Roeder, WP Vavrek, RJ Brody, FC Madura, JT Harms, DE GP AMS AMS TI Lightning safety for schools SO 10TH SYMPOSIUM ON EDUCATION LA English DT Proceedings Paper CT 10th Symposium on Education CY JAN 14-18, 2001 CL ALBUQUERQUE, NM SP Amer Meteorol Soc C1 45th Weather Squadron, SYR, Patrick AFB, FL 32925 USA. RP Roeder, WP (reprint author), 45th Weather Squadron, SYR, 1210 Edward H White 2, Patrick AFB, FL 32925 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2001 BP 89 EP 92 PG 4 WC Education, Scientific Disciplines SC Education & Educational Research GA BU98X UT WOS:000177563800033 ER PT B AU Harms, DE Boyd, BF Gremillion, MS Fitzpatrick, ME Hollis, TD AF Harms, DE Boyd, BF Gremillion, MS Fitzpatrick, ME Hollis, TD GP AMS AMS TI Weather support to space launch: A quarter-century look at weather instrumentation improvements SO 11TH SYMPOSIUM ON METEOROLOGICAL OBSERVATIONS AND INSTRUMENTATION LA English DT Proceedings Paper CT 11th Symposium on Meteorological Observations and Instrumentation CY JAN 14-18, 2001 CL ALBUQUERQUE, NM SP Amer Meteorol Soc C1 Weather Squadron 45th, Patrick AFB, FL 32925 USA. RP Boyd, BF (reprint author), 45 WS-SYA,1201 Edward H White II St,MS 7302, Patrick AFB, FL 32925 USA. NR 44 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2001 BP 259 EP 264 PG 6 WC Instruments & Instrumentation; Meteorology & Atmospheric Sciences SC Instruments & Instrumentation; Meteorology & Atmospheric Sciences GA BV01N UT WOS:000177602400059 ER PT B AU Johnson, MW AF Johnson, MW GP AMS AMS TI Weather support to USAF airborne laser SO 17TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY, AND HYDROLOGY LA English DT Proceedings Paper CT 17th International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography and Hydrology CY JAN 14-19, 2001 CL ALBUQUERQUE, NM SP Amer Meteorol Soc ID CIRRUS C1 USAF, Space & Missile Syst Ctr, Airborne Laser Syst Program Off, Kirtland AFB, NM 87117 USA. RP Johnson, MW (reprint author), USAF, Space & Missile Syst Ctr, Airborne Laser Syst Program Off, Kirtland AFB, NM 87117 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU AMER METEOROLOGICAL SOCIETY PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108 USA PY 2001 BP 57 EP 59 PG 3 WC Meteorology & Atmospheric Sciences; Oceanography; Water Resources SC Meteorology & Atmospheric Sciences; Oceanography; Water Resources GA BV02Z UT WOS:000177651500016 ER PT S AU Schoeppner, GA Mollenhauer, DH Iarve, E AF Schoeppner, GA Mollenhauer, DH Iarve, E BE Repecka, L Saremi, FF TI 3D spline variational analysis of a composite double-lap shear joint SO 2001: A MATERIALS AND PROCESSES ODYSSEY, BOOKS 1 AND 2 SE INTERNATIONAL SAMPE TECHNICAL CONFERENCE SERIES LA English DT Proceedings Paper CT 46th International SAMPE Symposium and Exhibition CY MAY 06-10, 2001 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE composite materials; joining; analysis; Moire interferometry AB Adhesive bonding has been used to join or repair metallic and/or composite structural components to achieve or restore their designed structural stiffness and strengths. It has been demonstrated in numerous programs over many years that the critical interlaminar adhesive stresses govern the lifetime performance and durability of adhesively bonded joints and repairs. Current design tools for composite bonded joints and repairs typically use laminate level analyzes in which the properties of the laminate are homogenized and the residual ply level stresses are neglected. This study uses the BSAM spline variational three dimensional ply level stress analysis method to model a double-lap shear specimen. Moire interferometry was used to measure the surface strains on the edge of the specimen in the bondline end region. A comparison of the predicted and experimentally measured strains shows excellent agreement. C1 USAF, Res Lab, AFRL, MLBC, Wright Patterson AFB, OH 45433 USA. RP Schoeppner, GA (reprint author), USAF, Res Lab, AFRL, MLBC, Wright Patterson AFB, OH 45433 USA. NR 12 TC 0 Z9 0 U1 0 U2 2 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA SN 0892-2624 BN 0-938994-90-5 J9 INT SAMPE TECH CONF PY 2001 VL 46 BP 72 EP 83 PG 8 WC Engineering, Chemical; Materials Science, Characterization & Testing; Materials Science, Composites SC Engineering; Materials Science GA BS96V UT WOS:000171526800008 ER PT S AU Watts, R Price, LJ Daniels, D Vrable, D Klosterman, E AF Watts, R Price, LJ Daniels, D Vrable, D Klosterman, E BE Repecka, L Saremi, FF TI Joint attachment of carbon-carbon aircraft HX core SO 2001: A MATERIALS AND PROCESSES ODYSSEY, BOOKS 1 AND 2 SE INTERNATIONAL SAMPE TECHNICAL CONFERENCE SERIES LA English DT Proceedings Paper CT 46th International SAMPE Symposium and Exhibition CY MAY 06-10, 2001 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE carbon-carbon composites; joining; analysis AB Because current high temperature (650 degreesC), metallic heat exchangers are heavy and typically made from metals possessing a low thermal conductivity, alternative high temperature materials are being investigated. An effort has been underway to develop a high temperature, carbon-carbon composite, aircraft heat exchanger. The heat exchanger core is a plate fin design and fabricated from a carbon-carbon composite and called an integral core process. This process involves co-processing the conductive fins and structural plates and then brazing together the plates of these structures. The effort to be discussed determined how to braze the carbon-carbon structures together to provide the required structural and thermal joint. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Watts, R (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA SN 0892-2624 BN 0-938994-90-5 J9 INT SAMPE TECH CONF PY 2001 VL 46 BP 658 EP 670 PG 3 WC Engineering, Chemical; Materials Science, Characterization & Testing; Materials Science, Composites SC Engineering; Materials Science GA BS96V UT WOS:000171526800058 ER PT S AU Banaszak, D Dale, GA Baust, HD AF Banaszak, D Dale, GA Baust, HD BE Repecka, L Saremi, FF TI Effectiveness of damped fiberglass patches on vibrating 2024-T3 plates SO 2001: A MATERIALS AND PROCESSES ODYSSEY, BOOKS 1 AND 2 SE INTERNATIONAL SAMPE TECHNICAL CONFERENCE SERIES LA English DT Proceedings Paper CT 46th International SAMPE Symposium and Exhibition CY MAY 06-10, 2001 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE fatigue crack measurement; temperature sensitive paint; damped repair patch AB The Air Force Research Laboratory (AFRL) completed experiments to determine the effectiveness of damped fiberglass bonded patches in reducing fatigue crack growth in secondary aircraft structures. Aircraft experience cracking in secondary structures such as wing trailing edge skins, fairings, and exhaust washed skin panels subjected to high cycle fatigue induced by out-of-plane excitation. Aerospace industries investigated extensively bonded composite repairs to, arrest and prevent fatigue cracks in primary structural components. Few studies focused on secondary structures. AFRL vibrated 2024-T3 aluminum plates (two thicknesses and two areas) on an electrodynamics shaker at resonance to accelerate out-of-plane fatigue. AFRL cracked eight plates to full width with no patch. Next AFRL cracked twelve plates to a length of 25mm by sinusoidal resonance and then installed damped fiberglass patches. A visual crack measurement system (VCMS) using temperature sensitive paint (TSP) measured the crack growth while vibrating the plates. Results include crack length versus cycle curves and an analysis of variance (ANOVA) to determine the statistical significance of the thickness, area and patching on the number of cycles to reach a 50mm crack length. The patch is successful in slowing crack growth for small thin aluminum plates with holes drilled in the center. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Banaszak, D (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA SN 0892-2624 BN 0-938994-90-5 J9 INT SAMPE TECH CONF PY 2001 VL 46 BP 1148 EP 1159 PG 8 WC Engineering, Chemical; Materials Science, Characterization & Testing; Materials Science, Composites SC Engineering; Materials Science GA BS96V UT WOS:000171526800101 ER PT S AU Donaldson, SL Kim, RY AF Donaldson, SL Kim, RY BE Repecka, L Saremi, FF TI Mode I fracture of a carbon fiber-reinforced bismaleimide composite at cryogenic temperatures SO 2001: A MATERIALS AND PROCESSES ODYSSEY, BOOKS 1 AND 2 SE INTERNATIONAL SAMPE TECHNICAL CONFERENCE SERIES LA English DT Proceedings Paper CT 46th International SAMPE Symposium and Exhibition CY MAY 06-10, 2001 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE cryogenic testing; interlaminar fracture; double cantilever beam test; compact tension test; energy release rate; Mode I AB Polymer matrix composites are being considered as the primary structural materials in cryogenic storage tanks. Potential uses of composite cryotanks include next generation reusable launch vehicles. A preliminary study was made to assess the opening Mode I interlaminar fracture performance of a carbon/bismaleimide composite material (Cytec IM7/5250-4) at both room temperature and while submersed in liquid nitrogen (-321 degrees F). Both the Double Cantilever Beam (DCB) and Compact Tension (CT) test specimens were utilized. A comparison of the DCB and CT test results is presented. C1 USAF, Res Lab, MLBC, Wright Patterson AFB, OH 45433 USA. RP Donaldson, SL (reprint author), USAF, Res Lab, MLBC, 2941 P St,Rm 136, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 1 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA SN 0892-2624 BN 0-938994-90-5 J9 INT SAMPE TECH CONF PY 2001 VL 46 BP 1557 EP 1563 PG 3 WC Engineering, Chemical; Materials Science, Characterization & Testing; Materials Science, Composites SC Engineering; Materials Science GA BS96V UT WOS:000171526800140 ER PT S AU Wood, BE Green, BD Uy, OM Cain, RP Yung, SK AF Wood, BE Green, BD Uy, OM Cain, RP Yung, SK BE Repecka, L Saremi, FF TI Satellite materials outgassing effects knowledgebase SO 2001: A MATERIALS AND PROCESSES ODYSSEY, BOOKS 1 AND 2 SE INTERNATIONAL SAMPE TECHNICAL CONFERENCE SERIES LA English DT Proceedings Paper CT 46th International SAMPE Symposium and Exhibition CY MAY 06-10, 2001 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE outgassing; satellite; QCM; materials; cryogenics AB Quartz crystal microbalances (QCMs) have been used extensively in the past for measuring contaminant mass deposition on surfaces either in ground test facilities or on satellites for space experiments. An American Standard Test Method (ASTM E1559) has been developed that uses QCMs for detailed evaluations of satellite materials outgassing properties. A knowledgebase has now been assembled which consolidates much of this type of data that has been previously generated. This effort was funded by the NASA Research Announcement (NRA820) out of the NASA Space and Environments Effects (SEE) Program Office. This paper describes the program that enables one to rapidly locate previous measurements on specific satellite materials. Data from past space flight experiments have been collected and are a part of the database. The database contains information on materials (similar to 225) outgassing obtained using the ASTM E1559 standard, and also space flight observations of contaminant mass deposition. This knowledgebase, provides a valuable source of material outgassing information. The data should be useful to. those working in the contamination technical area for satellite mission design and materials specification. Data have been accumulated from both national and international sources with NASA/GSFC, NASA/JSC, OSI, and ESTEC/ESA being contributors. The space flight database includes data from past NASA missions as well as DoD (including the BMDO-sponsored Midcourse Space Experiment (MSX) program), Canadian Space Agency, European Space Agency, Russian MIR space station, and eventually the International Space Station. A website has been established which is the vehicle for storing and accessing the data that have been accumulated. The website/database is managed by the NASA/SEE Program Office located at the Marshall Space Flight Center in Huntsville, Alabama. It became operational September 2000. C1 Sverdrup Technol Inc, Arnold AFB, TN USA. RP Wood, BE (reprint author), Sverdrup Technol Inc, Arnold AFB, TN USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA SN 0892-2624 BN 0-938994-90-5 J9 INT SAMPE TECH CONF PY 2001 VL 46 BP 1875 EP 1884 PG 4 WC Engineering, Chemical; Materials Science, Characterization & Testing; Materials Science, Composites SC Engineering; Materials Science GA BS96V UT WOS:000171526800167 ER PT S AU Bechel, V Janke, C Wilenski, M Tandon, GP AF Bechel, V Janke, C Wilenski, M Tandon, GP BE Repecka, L Saremi, FF TI Constituent level examination of an ebeam cured graphite/epoxy composite SO 2001: A MATERIALS AND PROCESSES ODYSSEY, BOOKS 1 AND 2 SE INTERNATIONAL SAMPE TECHNICAL CONFERENCE SERIES LA English DT Proceedings Paper CT 46th International SAMPE Symposium and Exhibition CY MAY 06-10, 2001 CL LONG BEACH, CA SP Soc Advancement Mat & Process Engn DE ebeam processing; polymer matrix composites; mechanical properties AB The relationships between the mechanical properties of the resin, interface, and composite laminate were investigated for an ebeam cured composite consisting of graphite fibers (IM7) in a toughened cationic epoxy resin (ORNL 3K). The goal was to gain insight into the relative contributions of the resin and interface characteristics to the poor transverse strength of this composite. Resin and composite properties were compared with two thermally cured graphite/epoxies and one thermally cured graphite/bismaleimide - AS4/3501-6, IM7/977-3, and IM7/5250-4, respectively. The tensile strength and strain-to-failure of 3K were significantly lower than the average for the three thermal cure resins while the fracture toughness and tensile modulus were nearly equivalent. Differences between the ebeam and thermally cured composites were also observed with respect to the mode of failure and the amount of fiber pullout on fractured laminates. To partially isolate the contribution of the resin a thermal postcure was used that significantly modified the resin mechanical properties while only slightly altering the resin cure shrinkage. The results indicate that it is unlikely that improvements to the resin mechanical properties alone would be sufficient to reach the laminate transverse strength of the thermally cured composites used as a baseline. C1 USAF, Res Lab, MLBC, Wright Patterson AFB, OH 45433 USA. RP Bechel, V (reprint author), USAF, Res Lab, MLBC, Rm 136,2941 P St, Wright Patterson AFB, OH 45433 USA. NR 13 TC 0 Z9 0 U1 0 U2 4 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA SN 0892-2624 BN 0-938994-90-5 J9 INT SAMPE TECH CONF PY 2001 VL 46 BP 2115 EP 2126 PG 6 WC Engineering, Chemical; Materials Science, Characterization & Testing; Materials Science, Composites SC Engineering; Materials Science GA BS96V UT WOS:000171526800187 ER PT B AU Hart, G Basinger, L AF Hart, G Basinger, L GP AESF AESF TI Technology use at tinker AFB SO 2001 AEROSPACE/AIRLINE PLATING & METAL FINISHING FORUM & EXPOSITION LA English DT Proceedings Paper CT Annual Aerospace/Airline Plating and Metal Finishing Forum CY MAR 27-29, 2001 CL PORTLAND, OR SP Amer Electroplaters & Surface Finishers Soc AB At the onset of toxic release reporting in 1994, Tinker AFB generated 1.8M pounds of toxic releases to the environment. This was enough to make TAFB the largest emitter of toxics in the Department of Defense (DoD). Today, Tinker has reduced its emissions by more than 84 percent through aggressive pollution prevention actions. This paper addresses technologies used to reduce the Toxic Release Inventory (TRI) emissions for the base while allowing production needs of this aerospace maintenance facility. C1 OC ALC EMV, Tinker AFB, OK 73145 USA. RP Hart, G (reprint author), OC ALC EMV, Bldg 1,7701 Arnold St, Tinker AFB, OK 73145 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ELECTROPLATERS SURFACE FINISHERS SOC INC PI ORLANDO PA 12644 RESEARCH PKWY, ORLANDO, FL 32826 USA PY 2001 BP 85 EP 88 PG 4 WC Engineering, Aerospace; Engineering, Mechanical; Metallurgy & Metallurgical Engineering SC Engineering; Metallurgy & Metallurgical Engineering GA BW96U UT WOS:000183794300012 ER PT S AU Zetocha, P Brito, M AF Zetocha, P Brito, M GP IEEE IEEE TI Development of a testbed for distributed satellite command and control SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB At the Air Force Research Laboratory's Space Vehicles Directorate we are investigating and developing architectures for commanding and controlling a cluster of cooperating satellites through prototype development for the TechSat-21 program. The objective of this paper is to describe a distributed satellite testbed that is currently under development and to summarize near term prototypes being implemented for cluster command and control. To design, develop, and test our architecture we are using eight PowerPC750 VME-based single board computers, representing eight satellites. Each of these computers is hosting the OSE (TM) real-time operating system from Enea Systems. At the core of our on-board cluster mana er is ObjectAgent. Object-Agent is an agent-based object-oriented framework for flight systems which is particularly suitable for distributed applications. In order to handle communication with the ground as well as to assist with cluster management we are using the Spacecraft Command Language (SCL). SCL is also at the centerpiece of our ground control station and handles cluster commanding, telemetry decommutation, state-of-health monitoring, and Fault Detection, Isolation, and Resolution (FDIR). For planning and scheduling activities we are currently using ASPEN from NASA/JPL. This paper will describe each of the above components in detail and then present the prototypes being implemented. C1 USAF, Res Lab, Space Vehicles Directorate, Washington, DC 20330 USA. RP Zetocha, P (reprint author), USAF, Res Lab, Space Vehicles Directorate, Washington, DC 20330 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 609 EP 614 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700062 ER PT S AU Steyskal, H Schindler, JK Franchi, P Mailloux, RJ AF Steyskal, H Schindler, JK Franchi, P Mailloux, RJ GP IEEE IEEE TI Pattern synthesis for TechSat21 - A distributed space-based radar system SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB The TechSat21 space-based radar employs a cluster of free-floating satellites, each of which transmits its own orthogonal signal and receives all reflected signals. The satellites operate coherently at X-band. The cluster forms essentially a multi-element interferometer with a concomitant large number of grating lobes and significant ground clutter. A novel technique for pattern synthesis in angle-frequency space is proposed, which exploits the double periodicities of the grating lobes in the angular domain and of the radar pulses in the frequency domain, and allows substantial gains in clutter suppression. Gains from 7 to 17 dB relative to the normal random, sparse array appear feasible. C1 AF Res Lab, SNH, Hanscom AFB, MA 01730 USA. RP Steyskal, H (reprint author), AF Res Lab, SNH, 80 Scott Dr, Hanscom AFB, MA 01730 USA. NR 4 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 725 EP 732 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700075 ER PT S AU Morton, TE AF Morton, TE GP IEEE IEEE TI Techniques to screen for moving and large stationary discretes in space-time adaptive estimation data SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE Aerospace Conference Proceedings LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc ID PERFORMANCE AB When the data samples used to estimate the interference covariance matrix in Space-Time Adaptive Processing (STAP) are assumed to be independent and identically distributed, an estimation loss indirectly proportional to the number of samples will occur. Measured data has shown that data samples are often nonhomogeneous and that these nonhomogeneities can cause losses beyond that from the estimation alone. Nonhomogeneities are of various types; here we have focused on moving and large stationary discretes. Numerical examples are presented that give a rationale for a screening technique. Then we present related screening techniques and performance simulations for the detection of moving and large stationary discretes in the estimation data. The screening techniques consist of pre-processing the samples by transforming them from the space-time domain to the angle-Doppler domain and exploiting the resulting interference characteristics. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. EM thomas.morton@sn.wpafb.af.mil NR 15 TC 0 Z9 0 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 853 EP 863 PG 11 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700089 ER PT S AU Salisbury, MS McManamon, PF Petrovich, D Barnes, LJ Schmoll, J AF Salisbury, MS McManamon, PF Petrovich, D Barnes, LJ Schmoll, J GP IEEE IEEE TI Cloud penetration laser radar experiments SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB This paper describes the modification of an Air Force Research Labs laboratory at WPAFB to allow testing and verification of the impact of clouds on EO sensors. A cloud of particles seventy-five feet in length can be created and characterized, including particle size distributions, uniformity measurements and overall optical depth. At the output of the cloud tube a hemispherical scanner can direct the beam to either a 2-4 kin test range or another laboratory for detailed measurements of the transmitted light. The detailed measurements include scattering profile measurements, polarization characterizations and temporal profiling which are all necessary to develop and verify theoretical models of system performance. A review of the cloud particle sizes and distributions that can be generated with the facility will be presented. An evaluation comparing the generated clouds to the clouds typically encountered operationally will be presented with an assessment of the facility limitations. The results from initial laser imaging experiments made at 1.54 microns with an InGaAs camera will be presented and evaluated. A detailed overview of experiments planned for the future will be given. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Salisbury, MS (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 1507 EP 1512 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700156 ER PT S AU McManamon, PF Watson, EA AF McManamon, PF Watson, EA GP IEEE IEEE TI Design of optical phased array beam steering with limited dispersion SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB This paper shows how the dispersion associated with optical phased array beam steering can be limited to moderate values of 20 to 80 times the diffraction limit even for very large angle beam steering. Much of the remaining factor of 20 - 80 may be correctable using digital techniques.(1) A significant obstacle associated with widespread implementation of optical phased array beam steering is the wavelength dispersion associated with resets.(2) In this paper we will discuss optical phased array beam steering using resets of greater than one wavelength. By using larger resets the unfolded phase front for wavelengths other than the design wavelength can be maintained closer to a prism, thus limiting dispersion. This technique can be implemented with the variable period beam steering approach and the variable blaze beam steering approach. One way to implement the variable blaze beam steering approach is using moveable lenslets.(3) This method of implementation is amenable to large value resets, so it is an attractive method of implementation for this multiple wavelength reset, limited dispersion, beam steering technique. By using resets of multiple wavelengths and limiting the dispersion we will be able to steer passive, broadband, electrooptical sensors over wide angles using optical phased array technology for the first time. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP McManamon, PF (reprint author), USAF, Res Lab, 2224 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 6 TC 2 Z9 2 U1 0 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 1583 EP 1591 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700165 ER PT S AU Watson, EA AF Watson, EA GP IEEE IEEE TI New imaging modalities for laser-based systems SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc ID FOCAL-PLANE ARRAY; RADAR AB Laser-based electro-optical sensors can gather spatial information (imagery) as well as a variety of other types of information. These include motion detection (including vibration), color sensing, and sensing of the effects of the illuminated object on the polarization of the incident illumination. Such systems can have several advantages over sensors that rely on reflected or emitted light. Laser-based systems can gather a full three dimensional image of an object on a single pulse. The sensors can gather this information in a covert manner because of the high directionality of the laser illumination. Also, a laser-based sensor can gather information with high resolution. In addition, the ability to control the illumination source, the receiver, and the optical aperture can lead to new sensing modalities. In this paper we describe various spatial and non-spatial sensing concepts and discuss hardware implementations. In particular we highlight the ability of laser-based systems to produce imagery at very low light levels. The utility of low light level imagery in two dimensions will be discussed and the potential benefits of three-dimensional low light level imagery will be assessed. The effect of intervening obscurants on low light level systems will be considered. Characteristics of systems that can implement such concepts will also be described. C1 USAF, Res Lab, ElectroOpt Technol Div, Wright Patterson AFB, OH 45433 USA. RP Watson, EA (reprint author), USAF, Res Lab, ElectroOpt Technol Div, AFRL-SNJ Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 16 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 1593 EP 1599 PG 7 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700166 ER PT S AU LeVan, P Lyke, J Waterman, JR Duffey, JR Paulsen, B AF LeVan, P Lyke, J Waterman, JR Duffey, JR Paulsen, B GP IEEE IEEE TI The passive sensor subsystem for DITP - Current status and projected performance SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB The passive sensor subsystem (PSS) is under development by the Air Force Research Laboratory as part of the DITP. which is a BMDO and tri-service flight demonstration of advanced interceptor technologies. We describe the PSS in terms of its three basic constituents the LWIR focal plane array (FPA), the flight cryostat assembly (FCA), and the malleable signal processor (MSP). We first review each of these basic constituents. We then describe how these constituents relate in the overall system, including the FPA in the operating environment provided by the Right cryostat assembly; the operation of, and data acquisition from. the FPA by the malleable signal processor; and the optical configuration used to achieve the desired pixel and FPA fields of view in both flight and ground-test embodiments. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP LeVan, P (reprint author), USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 2113 EP 2120 DI 10.1109/AERO.2001.931167 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700215 ER PT S AU Tomlinson, BJ AF Tomlinson, BJ GP IEEE IEEE TI Advanced cryogenic technology for space based infrared surveillance and stored cryogens SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB Current space cryocooler developments have achieved performance and capability that have made the use of active refrigeration in space missions feasible. Space Right demonstrations such as the Sandia National Laboratory Cobra Brass and Multispectral Thermal Imager missions, the National Aeronautics and Space Administration SABER, Hyperion, and AIRS missions baselined and implemented active refrigeration to achieve mission goals. The NASA retrofit of the NICMOS cooling system on the Hubble Space Telescope, due to be installed during a 2001 servicing mission, will use a reverse Brayton cycle cryocooler to provide cooling for the NICMOS sensor due to a prematurely depleted cryogen dewar. These applications of cryocooler technology validate the improved mission capabilities and reliability and lifetime confidence in active refrigeration in space. Current cryogenic integration and cryocooler development programs address the negative impacts of the cryogenic system on optical space systems including: induced line of sight vibration, longevity, power consumption, mass, thermal transport, thermal storage, and thermal switching. However, the cryogenic cooling requirements for future Air Force systems may require large capacity cryogenic cooling, extremely mass and power efficient mechanical refrigerators, and significant improvements in long term on orbit cryogen storage. The technical efforts at AFRL concentrate on exploratory and advanced development programs that focus on the development of technology from concept and breadboard engineering models to protoflight models that are geared to experimental characterization and technology transition for flight demonstrations and, potentially, operational programs. This paper will focus on mid term and out year cooling requirements for the Air Force Space Based Infrared System Low, Space Based Laser, Advanced Space Based Infrared System, and other Department of Defense space missions. In addition, current and planned Air Force programs to address these requirements will be outlined. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Tomlinson, BJ (reprint author), USAF, Res Lab, Space Vehicles Directorate, 3550 Aberdeen Blvd SE, Kirtland AFB, NM 87117 USA. NR 10 TC 0 Z9 0 U1 1 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 2121 EP 2136 DI 10.1109/AERO.2001.931168 PG 16 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700216 ER PT S AU Roush, FM Kalma, AH Kasai, I Venzor, GM Estrada, DA de Lyon, TJ Jensen, JE Kinch, MA Robinson, JE AF Roush, FM Kalma, AH Kasai, I Venzor, GM Estrada, DA de Lyon, TJ Jensen, JE Kinch, MA Robinson, JE GP IEEE IEEE TI High operating temperature FPAs for lighter, lower power satellite surveillance in the infrared SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB The Air Force Research Laboratory (AFRL) has pursued high temperature Infrared (IR) Focal Plane Arrays (FPAs) for three years. A 10K increase has been obtained to date under a contract with the Raytheon Infrared Operations (RIO) by thinning the HgCdTe base-layer. A contract has recently been let to DRS Infrared Technologies (DRS) to further increase operating temperature by 15K utilizing their gold doped High Density Vertically Integrated Photodiode (HDVIP (TM)) technology. The increased operating temperatures of these devices will reduce power, weight, and Costa as well as extend the lifetime of space surveillance satellites, satisfying a critical 21(st) century device technology need. C1 USAF, Res Lab, Lab VSSS, Kirtland AFB, NM 87117 USA. RP Roush, FM (reprint author), USAF, Res Lab, Lab VSSS, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 2137 EP 2148 DI 10.1109/AERO.2001.931169 PG 12 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700217 ER PT S AU Wegner, PM Ganley, J Maly, JR AF Wegner, PM Ganley, J Maly, JR GP IEEE IEEE TI EELV Secondary Payload Adapter (ESPA): Providing increased access to space SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB There currently exist few options for small satellites and space experiments needing access to space. Therefore, many small satellites wait years for access to space. At the same time, many expendable launch vehicles are flown every year with unused payload margin. The EELV Secondary Payload Adapter (ESPA) is designed to take advantage of this unused payload margin to deploy up to six 181 kg (400 lb) secondary payloads. ESPA consists of an aluminum cylinder with six standardized secondary payload (SPL) mounting locations. The fore and aft flanges on the ESPA ring duplicate the 157.5 cm (62.01 in) EELV Standard Interface Plane, making ESPA transparent to the primary payload. By taking advantage of existing unused payload margin, ESPA will increase access to space for small satellites and space experiments. C1 USAF, Res Lab, Space Vehicles Directorate, VS, Kirtland AFB, NM 87117 USA. RP Wegner, PM (reprint author), USAF, Res Lab, Space Vehicles Directorate, VS, 3550 Aberdeen Ave SE,Bldg 472, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 2563 EP 2568 DI 10.1109/AERO.2001.931218 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700263 ER PT S AU Ngo, AD Doman, DB AF Ngo, AD Doman, DB GP IEEE IEEE TI Dynamic inversion-based adaptive/reconfigurable control of the X-33 on ascent SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB A quaternion-based attitude control system is developed for the X-33 in the ascent flight phase. A non-linear control law commands body-axis rotation rates that align the angular velocity vector with an Euler-axis defining the axis of rotation that takes the body-axis system into a desired-axis system. The magnitudes of the commanded body rates are determined by the magnitude of the rotation error. The commanded body rates form the input to a dynamic inversion-based adaptive/reconfigurable control law. The indirect adaptive control portion uses on-line system identification to estimate the current control effectiveness matrix to update a control allocation module. The control allocation nominally operates in a minimum deflection mode; however, if a fault is detected, it can operate in a null-space injection mode that excites and decorrelates the effectors without degrading the vehicle response in order to enable on-line system identification. The overall system is designed to provide fault and damage tolerance for the X-33 on ascent. The baseline control law supports full envelope operation and eliminates trajectory dependent gain-scheduling that is typically found on this type of vehicle. Preliminary results are shown to demonstrate the feasibility of the approach. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Ngo, AD (reprint author), USAF, Res Lab, 2210 8th St,Suite 21, Wright Patterson AFB, OH 45433 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 2683 EP 2697 PG 15 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700273 ER PT S AU Cord, TJ Newbern, S AF Cord, TJ Newbern, S GP IEEE IEEE TI Unmanned air vehicles: New challenges in design SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB The last ten years have seen a gradual shift in emphasis on future aeronautical technologies towards autonomous operation. This is most evident in the extended planning and development of Unmanned Air Vehicles (UAVs). UAVs have grown from being target drones to Unmanned Combat Air Vehicles that will perform the Suppression of Enemy Air Defenses mission. Following generations may even include air-to-air combat. This presentation will briefly discuss some of the differences between manned and unmanned vehicles, will give two examples of tasks best performed autonomously and will end with a few thoughts on why members of IEEE should be interested. There are many reasons why UAVs are better suited to certain tasks. Certainly lower risk to operators and crew, lower cost and the removal of man-centered operational limitations are all on the positive side of the UAV choice. Eventually, they may be designed to overcome the deficiencies that UAVs currently show; lack of human intelligence for decision making in the face of unexpected events, added time delays for those cases where human intervention is required, reaction to failures of various sorts and others. Two projects serve as examples of the innovation with which the UAV is being considered. The first. Skytote, shows how UAVs are being considered for existing missions while reducing the risk to operators. This is a Small Business Innovative Research (SBIR) Phase II effort being conducted by AeroVironment Inc of Monrovia CA for the Air Force Research Laboratory's Air Vehicle Directorate. The primary mission of this autonomous vehicle is to precisely deliver a four-hundred-pound payload to a point within a 300-mile range in under two hours. The design is a Vertical Takeoff and Landing aircraft with a hover capability. Propulsion is provided by counter-rotating propellers with individual cyclic control. The major technical challenges in this effort are in the areas of propulsion and transition from wing-borne to propeller-borne flight. System challenges can be seen in the setting of the requirements to do a wide variety of jobs. The second, Sensorcraft, is a platform for active X-band and VHF radar systems to observe activity both on the ground and in the air. Several concepts are now under consideration by the major airframers. Autonomous operation at long range and long endurance at high altitude are the prime requirements for the vehicle. Every aspect of the design is pushed to the limit in order to achieve the goals. A point-design solution has been developed for the task, but traditional aircraft design methods and existing technology are not capable of providing any flexibility in the operational usage of the system. This is where innovation in development and application of, and interaction among, technologies may produce significant payoffs. Traditional design of aircraft obviously involves many disciplines covered by IEEE membership; power generation and distribution, flight control computers, instrumentation, and communications just to name a few. These have evolved to fit the specialized needs of the aerospace community: however, the needs of the future are not the same as the past. A new and revolutionary generation of air vehicles is just around the corner, one that has new uses, new flight envelopes and new requirements for interaction among many of the traditional technical disciplines. This also means new opportunities for advancement in system capability which is brought about by improvements in individual aspects of air vehicle design. This is not just a change for the aerodynamicist or structural engineer, but for all those involved with the definition of the air vehicle system. C1 USAF, RL, VAAA, Wright Patterson AFB, OH 45433 USA. RP Cord, TJ (reprint author), USAF, RL, VAAA, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 2 U2 18 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 2699 EP 2704 PG 6 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700274 ER PT S AU Friend, R AF Friend, R GP IEEE IEEE TI Turbine engine research in the United States air force SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB Propulsion technology has always been a key to the successful development of aeronautics and has enabled new air vehicles throughout the aerospace industry. Yet advancements in propulsion have been dependent upon advancements in aerodynamics, thermodynamics and especially materials technologies. These advancements have required careful guidance in their application to propulsion through detailed technology development, a transition path and linkage to future systems. Since the late Thirties, the gas turbine engine has provided an enormous step forward in operational capability but with it has come an equal step in cost. The Air Force Research Laboratory (AFRL) Propulsion Directorate (PR) has the mission to create and transition advanced air breathing, rocket propulsion and power technologies for military dominance of air and space. Its vision is to continue to be the world leader in military propulsion and power technology. This vision has been realized through coordinated research programs like the Integrated High Performance Turbine Engine Technology (IHPTET) and should be secured for the future with the follow-on Versatile Affordable Advanced Turbine Engines, VAATE. VAATE encompasses 3 research focus areas: Intelligent Engines, Versatile Core and Durability. Intelligent Engines will be high performance and be extremely damage tolerant. They will feature adaptive component performance. integrated propulsion and power generation, real time life tracking and proactive health management; these last 2 features are instrumental in reducing the cost of ownership. Why? Because 70% of affordability improvement is attributable to reduced cost of ownership. Engine Health Management (EHM) will enable the transition to on-condition based maintenance to provide the right support at the right time for the right reasons. Zn This paper covers the Propulsion Directorate's mission and vision, IHPTET, advanced turbine engines, VAATE, and Intelligent Engines. It provides the definition about the intelligence being sought for the Joint Strike Fighter (JSF), the concept and the vision for the maturing of comprehensive EHM systems being developed by AFRL, and underpins that what we develop today must be affordable. C1 Components Branch, Turbine Engine Div, Prop Directorate, Air Force Res Lab, Wright Patterson AFB, OH 45432 USA. RP Friend, R (reprint author), Components Branch, Turbine Engine Div, Prop Directorate, Air Force Res Lab, 1950 5th St,Bldg 18D, Wright Patterson AFB, OH 45432 USA. NR 10 TC 0 Z9 0 U1 1 U2 3 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 3165 EP 3178 PG 14 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700317 ER PT S AU Stanton, C Sellers, J AF Stanton, C Sellers, J GP IEEE IEEE TI Modeling and simulation tools for rapid space system analysis and design: FalconSat-2 applications SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB The FalconSat Program at the United States Air Force Academy is a small satellite organization in which participating undergraduate cadets design, build, test, and operate small satellites to carry Air Force or DoD scientific payloads. The team is currently designing FalconSat-2 to conduct measurements of plasma depletions in the ionosphere. Necessary to the design process is the development of requirements and behavioral models to analyze and simulate basic operational scenarios and their effects on the major satellite subsystems. This modeling can be used to preview the impact of potential design changes, reduce development time (especially during hardware and software integration and testing), and aid in training by providing operators with realistic simulations prior to launch. Modeling and simulation for the FalconSat Program uses commercial off-the-shelf software tools such as Excel and Matlab/Simulink environments. The paper describes some basic background on the program, followed by detailed discussion of models being developed and their effect on the evolution of the design. The current status of the design is presented as part of the conclusions. C1 USAF Acad, Small Satellite Res Ctr, Colorado Springs, CO 80841 USA. RP Stanton, C (reprint author), USAF Acad, Small Satellite Res Ctr, Colorado Springs, CO 80841 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 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 3479 EP 3487 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700348 ER PT S AU McQuay, WK AF McQuay, WK GP IEEE IEEE TI Distributed collaborative environments for the 21st century laboratory SO 2001 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOLS 1-7 SE IEEE AEROSPACE CONFERENCE PROCEEDINGS LA English DT Proceedings Paper CT IEEE Aerospace Conference CY MAR 10-17, 2001 CL BIG SKY, MT SP IEEE Aerosp & Electr Syst Soc AB Distributed collaboration is an emerging technology that will significantly change how business and research is conducted in 21(st) century. As down-sizing trends continue in both government and industry, organizations increasingly require more efficient. effective collaboration and knowledge sharing for geographically dispersed personnel across multiple application domains in order to solve complex problems and accomplish difficult tasks. Past research has treated knowledge sharing as an information technology problem and has ignored an organization's culture and related process changes needed for successful collaboration. This paper reviews the application of distributed collaborative environments employing an agent-based framework with emphasis on product and process modeling to enable information and knowledge sharing for Air Force acquisition and technology development. This research is a significant benchmark in the evolution of collaboration in that information technology, process change, and the sociology of human interaction are woven into a fabric of knowledge sharing - the knowledge focused organization. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP McQuay, WK (reprint author), USAF, Res Lab, 2241 Avion Cir,RM N3F22, Wright Patterson AFB, OH 45433 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1095-323X BN 0-7803-6599-2 J9 AEROSP CONF PROC PY 2001 BP 3557 EP 3565 PG 9 WC Engineering, Aerospace; Engineering, Electrical & Electronic SC Engineering GA BT34X UT WOS:000172696700356 ER PT S AU Lin, DM Tsui, JBY AF Lin, DM Tsui, JBY BE Sigmon, B TI A software GPS receiver for weak signals SO 2001 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-3 SE IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST LA English DT Proceedings Paper CT IEEE MTT-S International Microwave Symposium CY MAY 20-25, 2001 CL PHOENIX, AZ SP IEEE, MTTS AB The paper reports the approach and results of a stand alone software global positioning system (GPS) receiver. The receiver is specially designed to receive weak signals without aids from other information sources. The approaches for the acquisition, first navigation phase detection, and tracking are discussed. The different kinds of thresholds with different signal-to-noise ratio (S/N) are developed. Under the best operating condition a signal can be 15 dB below the normal noise level and still be processed. C1 USAF, Sensors Directorate, RF Technol Div, Wright Patterson AFB, OH 45433 USA. RP Lin, DM (reprint author), USAF, Sensors Directorate, RF Technol Div, Wright Patterson AFB, OH 45433 USA. NR 5 TC 2 Z9 6 U1 0 U2 1 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0149-645X BN 0-7803-6713-8 J9 IEEE MTT-S PY 2001 BP 2139 EP 2142 PG 4 WC Engineering, Electrical & Electronic; Optics; Physics, Applied; Telecommunications SC Engineering; Optics; Physics; Telecommunications GA BU13J UT WOS:000175125500502 ER PT B AU Duggan, P Sampson, S Burnell, R Koga, R Yu, P Crain, S McEndree, S Tausch, J Sleeter, D Alexander, D AF Duggan, P Sampson, S Burnell, R Koga, R Yu, P Crain, S McEndree, S Tausch, J Sleeter, D Alexander, D GP IEEE IEEE TI Comparative testing of ADSP-21020 digital signal processors from multiple vendors SO 2001 IEEE RADIATION EFFECTS DATA WORKSHOP, WORKSHOP RECORD LA English DT Proceedings Paper CT 10th IEEE Radiation Effects Data Workshop (REDW) held in conjunction with the 38th Annual IEEE Nuclear and Space Radiation Effects Conference CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE Nucl & Plasma Sci Soc, IEEE AB Total ionizing dose, ionizing dose rate, and single event effects test results are reported on the ADSP-21020 by Analog Devices Inc., the RH21020 by BAE Systems/Manassas, and the TSC21020F by Atmel Wireless and Microcontrollers. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Duggan, P (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7199-2 PY 2001 BP 19 EP 25 DI 10.1109/REDW.2001.960443 PG 7 WC Engineering, Electrical & Electronic; Physics, Nuclear SC Engineering; Physics GA BT43B UT WOS:000172972300004 ER PT B AU Bryant, ML Gostin, LL Soumekh, M AF Bryant, ML Gostin, LL Soumekh, M GP IEEE IEEE TI Three-dimensional E-CSAR imaging of a T-72 tank and synthesis of its spotlight, stripmap and interferometric SAR reconstructions SO 2001 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING, VOL III, PROCEEDINGS LA English DT Proceedings Paper CT International Conference on Image Processing (ICIP 2001) CY OCT 07-10, 2001 CL THESSALONIKI, GREECE SP IEEE Signal Processing Soc, IEEE AB This paper presents the results of three-dimensional imaging of a T-72 tank using its angular azimuthal (turntable) and linear elevation synthetic aperture data at X band This is achieved using an accurate and computationally-efficient wavefront (Fourier-based) reconstruction algorithm for elevation and circular (E-CSAR) data The E-CSAR 3-D images are then used to synthesize 2-D spotlight and stripmap slant plane SAR images of the target at a desired range and squint angle For this purpose, a procedure is introduced that incorporates the spatially-varying azimuthal and elevation Doppler signatures of individual reflectors on the target as well as the mean range, azimuth and elevation of the flight path Results using the E-CSAR images of the T-72 tank are provided. C1 USAF, Res Lab, Sensors Directorate Target Recognit Branch, Wright Patterson AFB, OH 45433 USA. RP Bryant, ML (reprint author), USAF, Res Lab, Sensors Directorate Target Recognit Branch, Wright Patterson AFB, OH 45433 USA. NR 5 TC 2 Z9 2 U1 1 U2 2 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-6725-1 PY 2001 BP 628 EP 631 PG 4 WC Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA BV17H UT WOS:000178056400162 ER PT S AU Quach, T Okamura, W Gutierrez-Aitken, A Jenkins, T Kaneshiro, E Kehias, L Oki, A Sawdai, D Watson, P Welch, R Worley, R Yen, HC AF Quach, T Okamura, W Gutierrez-Aitken, A Jenkins, T Kaneshiro, E Kehias, L Oki, A Sawdai, D Watson, P Welch, R Worley, R Yen, HC GP IEEE IEEE TI Ultra-efficient X-Band and linear-efficient Ka-Band power amplifiers using indium phosphide double heterojunction bipolar transistors SO 2001 INTERNATIONAL CONFERENCE ON INDIUM PHOSPHIDE AND RELATED MATERIALS, CONFERENCE PROCEEDINGS SE CONFERENCE PROCEEDINGS - INDIUM PHOSPHIDE AND RELATED MATERIALS LA English DT Proceedings Paper CT 13th International Conference on Indium Phosphide and Related Materials (IPRM) CY MAY 14-18, 2001 CL NARA, JAPAN SP Japan Soc Appl Phys, IEEE Lasers & Electro Opt Soc, IEEE Electron Devices Soc, Inst Electr, Informat & Commun Engineers, Optoelectr Ind & Technol Dec Assoc, Res & Dev Assoc Future Electron Devices AB We report on an ultra-efficient circuit at X-Band and a linear-efficient circuit at Ka-Band using InP double heterojunction bipolar transistors (DHBTs). The high efficiency circuit employs a transmission line Class-E topology to achieve 61.1 % PAE, 20.1-dBm output power, and 9.8-dB gain at 10 GHz. The linear efficient circuit combines four unit cells of 1.5 mum X 30 mum X 2 fingers that yielded 25.2 dBm output power, 8.4-dB linear gain, and 35.2 % PAE at 28 GHz. This circuit also achieved 31 to 34 dBm output IP3. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Quach, T (reprint author), USAF, Res Lab, 2241 Avion Circle,Bldg 620, 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 1092-8669 BN 0-7803-6700-6 J9 CONF P INDIUM PHOSPH PY 2001 BP 501 EP 504 DI 10.1109/ICIPRM.2001.929189 PG 4 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT18Y UT WOS:000172226900128 ER PT B AU Bonser, W AF Bonser, W GP IEEE IEEE TI "Engineering design steps for fast, simple and economical waveform development" SO 2001 MILCOM, VOLS 1 AND 2, PROCEEDINGS: COMMUNICATIONS FOR NETWORK-CENTRIC OPERATIONS: CREATING THE INFORMATION FORCE LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 2001) CY OCT 28-31, 2001 CL MCLEAN, VA SP IEEE, ComSoc, AFCEA, EDS, MITRE AB The software defined radio (SDR) has the potential to drastically reduce the types of radios in the inventory since a single hardware pack-age can be programmed to replicate the coding, modulation and other signaling features now used in legacy networks, plus adapt to next generation developments. Future Department of Defense (DoD) radios can benefit from this software programmability and thus simplify interoperability, maintenance, and life cycle cost concerns. Methods for the rapid development and distribution of waveform software must be created in order to realize the full potential of a communications system that can change parameters such as waveform, operating frequency, protocols, and error correction. There needs to be a standard SDR waveform development process addressing all of the engineering design steps for faster, simpler and more economical waveform development. This paper discusses the following issues and provides clear answers to these questions: Why do we want (or need) a Waveform Development Environment(WDE)? Can HW/SW decisions be pushed down to the lowest appropriate decomposition level? Should the language be standardized so that it has the widest potential applicability? Could the environment build upon the latest multimedia developments, so that they could be both more affordable and supportable? Should there be a definitive migration path towards future upgrades (e.g. Internet and web-based technologies)?. C1 USAF, Res Lab, Informat Directorate, Rome, NY USA. RP Bonser, W (reprint author), USAF, Res Lab, Informat Directorate, Rome, NY USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7225-5 PY 2001 BP 195 EP 201 PG 7 WC Computer Science, Information Systems; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BV22G UT WOS:000178199600037 ER PT B AU Klein, RW Temple, MA Claypoole, RL Raines, RA Stephens, JP AF Klein, RW Temple, MA Claypoole, RL Raines, RA Stephens, JP GP IEEE IEEE TI Wavelet domain communication system (WDCS) interference avoidance capability: Analytic, modeling and simulation results SO 2001 MILCOM, VOLS 1 AND 2, PROCEEDINGS: COMMUNICATIONS FOR NETWORK-CENTRIC OPERATIONS: CREATING THE INFORMATION FORCE LA English DT Proceedings Paper CT IEEE Military Communications Conference (MILCOM 2001) CY OCT 28-31, 2001 CL MCLEAN, VA SP IEEE, ComSoc, AFCEA, EDS, MITRE AB A recently proposed wavelet domain communication system (WDCS) using transform domain processing is demonstrated as having enhanced interference avoidance capability under adverse environmental conditions. The proposed WDCS and its response to various interference scenarios are modeled and simulation results obtained using MATLAB((R)). Relative to a system without suppression capability and a developmental, Fourier-based transform domain communication system (TDCS), the WDCS provides improved/comparable bit error performance in several interference scenarios - single-tone, multiple-tone, swept-tone, and partial-band interference is considered. The system was evaluated using an E-b/N-o of 4.0 dB and interference energy-to-signal energy (I/E) ratios ranging from 0 dB to 16.0 dB. For antipodal data modulation cases, the average WDCS bit error performance improvement was 12.4 dB relative to a system without suppression capability, approximately, equaling TDCS results. For orthogonal data modulation, average WDCS improvement was 5.7 dB versus 6.8 dB for the TDCS. Collectively, these results indicate the proposed WDCS is a viable option for interference avoidance communications. C1 USAF, Inst Technol, Wright Patterson AFB, OH 45433 USA. RP Klein, RW (reprint author), USAF, Inst Technol, 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 0-7803-7225-5 PY 2001 BP 1034 EP 1038 PG 5 WC Computer Science, Information Systems; Computer Science, Software Engineering; Engineering, Electrical & Electronic; Telecommunications SC Computer Science; Engineering; Telecommunications GA BV22G UT WOS:000178199600189 ER PT S AU Kwiat, K AF Kwiat, K GP IEEE COMPUTER SOCIETY IEEE COMPUTER SOCIETY TI Can reliability and security be joined reliably and securely? SO 20TH IEEE SYMPOSIUM ON RELIABLE DISTRIBUTED SYSTEMS, PROCEEDINGS SE SYMPOSIUM ON RELIABLE DISTRIBUTED SYSTEMS, PROCEEDINGS LA English DT Proceedings Paper CT 20th IEEE Symposium on Reliable Distributed Systems (SRDS 2001) CY OCT 28-31, 2001 CL NEW ORLEANS, LA SP IEEE Comp Soc Tech Comm Distributed Proc AB The combined topics of reliability and security are briefly traced in relation to the past and present endeavors of the Air Force Research Laboratory's Information Directorate. C1 USAF, Res Lab, AFRL, IFGA, Rome, NY USA. RP Kwiat, K (reprint author), USAF, Res Lab, AFRL, IFGA, Rome, NY USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1264 USA SN 1060-9857 BN 0-7695-1367-0 J9 SYM REL DIST SYST PY 2001 BP 72 EP 73 PG 2 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA BT60B UT WOS:000173448100009 ER PT S AU Snyder, DR Sierakowski, RL Chenette, ER Aus, JW AF Snyder, DR Sierakowski, RL Chenette, ER Aus, JW BE Takayama, K Saito, T Kleine, H Timofeev, E TI Preliminary assessment of electrothermomagnetically loaded composite panel impact resistance/crack propagation with high-speed digital laser photography SO 24TH INTERNATIONAL CONGRESS ON HIGH-SPEED PHOTOGRAPHY AND PHOTONICS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 24th International Congress on High-Speed Photography and Photonics CY SEP 24-29, 2000 CL SENDAI, JAPAN SP Tohoku Univ, Inst Fluid Sci, Shock Wave Res Ctr, Iwate Med Univ, Natl Inst Mat & Chem Res DE composite; ballistic; impact; terminal ballistics; crack propagation; electromagnetic response of materials; laser photography; high speed photography; million frame per second; CCD; multipulse laser ID CCD CAMERA AB This reports documents the baseline development of high-speed laser photography based assessment technique to determine effects of material resistance to puncture or fracture. A series of ballistic experiments were performed to at the Dynamic Event Imaging Laboratory at the Munitions Directorate, Air Force Research Laboratory site at Eglin, AFB, Florida. These experiments were performed, to assess the effectiveness of laser photography to document the formation and propagation,of cracks in composite materials with and without electromagnetic loading. These experiments were the first fully operational use of a novel and unique experimental capability for high-speed digital laser photography. This paper details the development of the experimental procedures and initial results of this exciting new tool. This report documents the experiments performed and the instrumentation developed along with recommendations for additional research. C1 USAF, Res Lab, Eglin AFB, FL 32542 USA. RP Snyder, DR (reprint author), USAF, Res Lab, Eglin AFB, FL 32542 USA. NR 19 TC 3 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 0-8194-3846-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4183 BP 488 EP 513 DI 10.1117/12.424316 PG 26 WC Engineering, Biomedical; Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology SC Engineering; Instruments & Instrumentation; Optics; Imaging Science & Photographic Technology GA BS87W UT WOS:000171311700056 ER PT S AU Cinibulk, MK Keller, KA Mah, TI Parthasarathy, TA AF Cinibulk, MK Keller, KA Mah, TI Parthasarathy, TA BE Singh, M Jessen, T TI Nextel 610 and 650 fiber reinforced porous alumina-YAG matrix composites SO 25TH ANNUAL CONFERENCE ON COMPOSITES, ADVANCED CERAMICS, MATERIALS, AND STRUCTURES: A SE CERAMIC ENGINEERING AND SCIENCE PROCEEDINGS LA English DT Proceedings Paper CT 25th Annual Conference on Composites, Advanced Ceramics, Materials and Structures CY JAN 21-27, 2001 CL COCOA BEACH, FL SP Amer Ceram Soc ID TRANSMISSION ELECTRON-MICROSCOPY; CERAMIC COMPOSITE; COATINGS AB A two-phase matrix consisting of alumina particles bonded with YAG was reinforced with Nextell(TM) 610 cloth or Nextel(TM) 650 tows. The use of a solution-derived YAG as a second phase in the matrix was intended to coat fibers as well. However, due to the small amount of YAG allowed in the matrix during composite processing, YAG was not homogeneously distributed throughout the matrix and filled only a small fraction of the porosity. Segregation of yttrium was observed at all alumina grain boundaries in the matrix. The stress-strain behavior of the composites was compared to that of composites that did not contain the YAG second phase. In all cases the YAG-containing composites gave higher ultimate stresses and greater strains to failure than the all-alumina composites when processed at 1200degreesC. Composite strength of the alumina-YAG matrix composites was likely increased by minimizing either fiber degradation or matrix densification. Nextel 650 fiber-reinforced composites heat treated at 1200degreesC for 100 h had the same reduced strength, due to severe fiber degradation. C1 Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Cinibulk, MK (reprint author), Air Force Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RI Parthasarathy, Triplicane/B-7146-2011 OI Parthasarathy, Triplicane/0000-0002-5449-9754 NR 14 TC 3 Z9 3 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 0196-6219 J9 CERAM ENG SCI PROC PY 2001 VL 22 IS 3 BP 677 EP 686 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Ceramics; Materials Science, Composites SC Engineering; Materials Science GA BW85N UT WOS:000183407900078 ER PT S AU Steel, SG Zawada, LP Mall, S AF Steel, SG Zawada, LP Mall, S BE Singh, M Jessen, T TI Fatigue behavior of a Nextel (TM) 720/alumina (N720/A) composite at room and elevated temperature SO 25TH ANNUAL CONFERENCE ON COMPOSITES, ADVANCED CERAMICS, MATERIALS, AND STRUCTURES: A SE CERAMIC ENGINEERING AND SCIENCE PROCEEDINGS LA English DT Proceedings Paper CT 25th Annual Conference on Composites, Advanced Ceramics, Materials and Structures CY JAN 21-27, 2001 CL COCOA BEACH, FL SP Amer Ceram Soc ID CERAMIC-MATRIX-COMPOSITE; PERFORMANCE AB An oxide/oxide ceramic matrix composite (CMC) with no interphase at the fiber-matrix interface was characterized under monotonic tensile testing and cyclic tensile loading at 23degreesC and 1200degreesC. The effect of room temperature moisture exposure on fatigue behavior was also examined at 1200degreesC. The composite consisted of 10 plies of 8HSW Nextel (TM) 720 fabric in a porous all alumina matrix. At 23degreesC the average ultimate tensile strength was 144 MPa and the maximum fatigue stress to achieve run Out (10(5) cycles and 1 Hz) was 102 MPa. At 1200degreesC average ultimate strength was 140 MPa and the maximum fatigue stress to achieve run out was 122 MPa. Periodic exposure to moisture did not degrade fatigue strength at 1200degreesC. Test specimens that achieved run out were tension tested at 23degreesC and exhibited retained tensile strength equal to or greater than the as-received test specimens. C1 USAF, Res Lab, Mat & Mfg Directorate, Met Ceram & NDE Div, Wright Patterson AFB, OH 45433 USA. RP Steel, SG (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Met Ceram & NDE Div, 2230 10th St,Suite 1, Wright Patterson AFB, OH 45433 USA. NR 7 TC 19 Z9 19 U1 1 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 0196-6219 J9 CERAM ENG SCI PROC PY 2001 VL 22 IS 3 BP 695 EP 702 PG 8 WC Engineering, Electrical & Electronic; Materials Science, Ceramics; Materials Science, Composites SC Engineering; Materials Science GA BW85N UT WOS:000183407900080 ER PT S AU Mall, S AF Mall, S BE Singh, M Jessen, T TI Response of graphite/epoxy laminates embedded with piezoelectric sensor under fatigue loading SO 25TH ANNUAL CONFERENCE ON COMPOSITES, ADVANCED CERAMICS, MATERIALS, AND STRUCTURES: B SE CERAMIC ENGINEERING AND SCIENCE PROCEEDINGS LA English DT Proceedings Paper CT 25th Annual Conference on Composites, Advanced Ceramics, Materials and Structures CY JAN 21-27, 2001 CL COCOA BEACH, FL SP Amer Ceram Soc AB Effects of embedding the active PZT sensor/actuator on the fatigue behavior of the quasi-isotropic graphite/epoxy laminate were investigated. Also, degradation in voltage output of embedded piezo device was monitored to assess its health (i.e. sensing or actuation capability) under the real loading environment. Graphite/epoxy (AS4/3501-6) laminates were fabricated with either [0/+/-45/90](s) or [0/0/+/-45/0/0/90](s) lay-ups. A commercially available piezo device in the prepackaged form was inserted in the laminate in two manners, one method involved placing them into a cut-out area in the two middle 90 plies, and the second method involved insertion between the two middle 90 plies without any cut-out. The fatigue lives with and without piezo device for each laminate lay-up were similar. Further, these were not affected by the embedment method of piezo device. Thus, the embedment of piezo device by cut-out or simple insertion method in the 90 plies appears to have no effect on degradation of structural fatigue strength. Also, the embedded piezo device maintained a steady voltage output indefinitely when mechanically cycled within their operational design limits. C1 USAF, Res Lab, MLLMN, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, Res Lab, MLLMN, Mat & Mfg Directorate, 2950 P St Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, WESTERVILLE, OH 43081-8720 USA SN 0196-6219 J9 CERAM ENG SCI PROC PY 2001 VL 22 IS 4 BP 521 EP 529 PG 9 WC Engineering, Electrical & Electronic; Materials Science, Ceramics; Materials Science, Composites SC Engineering; Materials Science GA BW85P UT WOS:000183408400060 ER PT S AU Barchers, JD AF Barchers, JD BE Tyson, RK Bonaccini, D Roggemann, MC TI Increase in point spread function uniformity over the compensated field of view in strong scintillation using two deformable mirrors SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology II CY JUL 30-AUG 01, 2001 CL SAN DIEGO, CA SP SPIE DE multi-conjugate adaptive optics; propagation; turbulence ID MULTICONJUGATE ADAPTIVE OPTICS; LASER-BEAM PROJECTION; PERFORMANCE AB The weighted parallel generalized projection algorithm is applied in two steps to the control of two deformable mirrors using multiple wavefront sensing beacons to simultaneously increase the compensated field of view while maximizing point spread function uniformity. Wave optical simulation results are presented that indicate that, even in strong scintillation, not only can the size of the compensated field of view be increased, but also the uniformity of the point spread function over the compensated field of view can be improved by augmentation of constraints enforcing point spread function uniformity. C1 USAF, Res Lab, DES, Starfire Opt Range,Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Barchers, JD (reprint author), USAF, Res Lab, DES, Starfire Opt Range,Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 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 0-8194-4208-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4494 BP 121 EP 131 AR UNSP 4494-16 PG 11 WC Instruments & Instrumentation; Remote Sensing; Optics; Physics, Applied SC Instruments & Instrumentation; Remote Sensing; Optics; Physics GA BU15M UT WOS:000175163000013 ER PT S AU Barchers, JD Rhoadarmer, TA Lee, DJ AF Barchers, JD Rhoadarmer, TA Lee, DJ BE Tyson, RK Bonaccini, D Roggemann, MC TI Identification of the registration of a deformable mirror to a Schack Hartmann wavefront sensor in an adaptive optical system SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology II CY JUL 30-AUG 01, 2001 CL SAN DIEGO, CA SP SPIE DE adaptive optics; alignment; registration AB A method for determining the registration of an adaptive optical system is presented. Three deformable mirror actuators are sinusoidally driven at a high rate and the resulting gradients are measured using a Hartmann sensor. The gradient measurements are used to determine the translational, rotational, and magnificational registration of the deformable mirror relative to the Hartmann wavefront sensor. Two configurations are presented. The first is not effected by the compensation system but requires the use of auxiliary beams outside the clear aperture of the adaptive optical system. In the second configuration, the dithering actuators are within the clear aperture of the adaptive optical system. Simulation results are presented that show that the method can be used reliably in either configuration. In the second configuration, the method can be used reliably even in the presence of residual amplitude and phase aberrations. C1 Air Force Res Lab, DES, Starfire Opt Range, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Barchers, JD (reprint author), Air Force Res Lab, DES, Starfire Opt Range, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 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 0-8194-4208-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4494 BP 188 EP 201 AR UNSP 4494-22 PG 14 WC Instruments & Instrumentation; Remote Sensing; Optics; Physics, Applied SC Instruments & Instrumentation; Remote Sensing; Optics; Physics GA BU15M UT WOS:000175163000019 ER PT S AU Whiteley, MR Washburn, DC Wright, LA AF Whiteley, MR Washburn, DC Wright, LA BE Tyson, RK Bonaccini, D Roggemann, MC TI Differential-tilt technique for saturation-resistant profiling of atmospheric turbulence SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology II CY JUL 30-AUG 01, 2001 CL SAN DIEGO, CA SP SPIE DE differential tilt; turbulence profiling; atmospheric characterization ID SANDS-MISSILE-RANGE; ADAPTIVE OPTICS; NEW-MEXICO; SCINTILLATION; RADAR; ANISOPLANATISM; COMPENSATION AB A technique for profiling of C-n(2) over an atmospheric propagation path is proposed, developed and analyzed. The technique employs differential-tilt measurements to arrive at statistics which have unique weighting functions over the propagation path. These weighting functions are computed theoretically and used to derive a reconstructor matrix for C-n(2) values throughout the path to be applied to an appropriate set of differential-tilt statistics. A candidate optical system is presented, and the performance of the profile reconstructor is analyzed. This study indicates that the relative error in the C,2 estimates is approximately 5%. The relative error in estimating key atmospheric parameters such as the Fried parameter, isoplanatic angle, and the Rytov parameter from the reconstructed profiles is approximately 3%. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Whiteley, MR (reprint author), USAF, Res Lab, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 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 0-8194-4208-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4494 BP 221 EP 232 AR UNSP 4494-28 PG 12 WC Instruments & Instrumentation; Remote Sensing; Optics; Physics, Applied SC Instruments & Instrumentation; Remote Sensing; Optics; Physics GA BU15M UT WOS:000175163000022 ER PT S AU Rhoadarmer, TA Barchers, JD Spillar, EJ AF Rhoadarmer, TA Barchers, JD Spillar, EJ BE Tyson, RK Bonaccini, D Roggemann, MC TI Complex field reconstruction using gradient and intensity measurements from a Shack-Hartmann wave front sensor SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology II CY JUL 30-AUG 01, 2001 CL SAN DIEGO, CA SP SPIE DE adaptive optics; wave front sensors; wave front reconstruction; scintillation ID ADAPTIVE-OPTICS; COMPENSATION; DISTORTION; PHASE; TURBULENCE; SYSTEMS; PERFORMANCE; TELESCOPE AB In many adaptive optical systems the standard wave front sensing and reconstruction process involves a conventional least squares reconstruction of gradient measurements obtained from a Shack-Hartman wave front sensor (WFS). This reconstruction algorithm assumes the WFS measurements are equal to the average phase gradient within each subaperture. However, this assumption does not account for the effects of scintillation in the wave front. As scintillation increases, intensity fluctuations in the wave front increase the disparity between the output of the WFS and what the reconstruction algorithm expects, which in turn causes a degradation in the performance of the reconstructor. We present an algorithm that attempts to mitigate the scintillation problem by reconstructing the real and imaginary components of the wave front using gradient and intensity information obtained from a Shack-Hartmann WFS. This algorithm estimates the wave front by inverting a more precise model of the WFS measurement process. Wave optics simulations over a variety of atmospheric conditions are used to compare the performance of our algorithm against a least squares reconstructor and a complex exponential reconstructor. C1 USAF, Res Lab, Directed Energy Directorate, Starfire Opt Range, Kirtland AFB, NM 87117 USA. RP Rhoadarmer, TA (reprint author), USAF, Res Lab, Directed Energy Directorate, Starfire Opt Range, Kirtland AFB, NM 87117 USA. NR 25 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 0-8194-4208-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4494 BP 233 EP 244 AR UNSP 4494-29 PG 12 WC Instruments & Instrumentation; Remote Sensing; Optics; Physics, Applied SC Instruments & Instrumentation; Remote Sensing; Optics; Physics GA BU15M UT WOS:000175163000023 ER PT S AU De La Rue, IA Ellerbroek, BL AF De La Rue, IA Ellerbroek, BL BE Tyson, RK Bonaccini, D Roggemann, MC TI Multi-conjugate adaptive optics with hybrid laser beacon systems SO ADAPTIVE OPTICS SYSTEMS AND TECHNOLOGY II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Adaptive Optics Systems and Technology II CY JUL 30-AUG 01, 2001 CL SAN DIEGO, CA SP SPIE DE multi-conjugate adaptive optics; adaptive optics; multiple laser guide stars; laser guide stars; anisoplanatism ID PERFORMANCE; TELESCOPES AB Results for a multi-conjugate adaptive optical (MCAO) system with multiple laser beacons at multiple altitudes are presented in this paper. The use of multi-conjugate deformable mirrors (DM's) increases the corrected field of view of an adaptive optical telescope system. This improves the imaging capability for extended astronomical objects such as planets, galaxies, and nebulae. Multiple laser beacons, as opposed to multiple natural guide stars, are needed to achieve a useful degree of sky coverage. The use of laser beacons at multiple altitudes in a hybrid laser beacon configuration has been shown in previous papers to reduce both focus and tilt anisoplanatism. In this study we combine all three of these aspects. The hybrid beacon scenarios used in this study consists of multiple high altitude sodium beacons at 90 km and/or multiple low altitude Rayleigh beacons at 10 to 20 km. We present results for an 8-m class telescope for 2 and 3 different DM conjugate altitudes. For each of these MCAO configurations the following parameters are varied: number of Rayleigh beacons, number of Rayleigh beacon wavefront sensor (WFS) subapertures, Rayleigh beacon altitudes for the Rayleigh/sodium configuration, number of natural beacons for tip/tilt correction. and number of natural beacon WFS subapertures. When the WFS subaperture for the natural beacon is greater than 1 x I it contributes to the higher order correction in addition to being used for tip/tilt correction. Results are compared in terms of Strehl Ratio for the J. H, and K band. C1 Air Force Res Lab, Starfire Opt Range, Directed Energy Directorate DES, Kirtland AFB, NM 87117 USA. RP De La Rue, IA (reprint author), Air Force Res Lab, Starfire Opt Range, Directed Energy Directorate DES, 3550 Aberdeen Ave, Kirtland AFB, NM 87117 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4208-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4494 BP 290 EP 301 AR UNSP 4494-37 PG 12 WC Instruments & Instrumentation; Remote Sensing; Optics; Physics, Applied SC Instruments & Instrumentation; Remote Sensing; Optics; Physics GA BU15M UT WOS:000175163000029 ER PT J AU Al-Hussien, M Mall, S Calcaterra, JR AF Al-Hussien, M Mall, S Calcaterra, JR TI Fatigue behavior of Nextel (TM) 312/Blackglas (TM) ceramic matrix composite with tensile and zero mean load SO ADVANCED COMPOSITE MATERIALS LA English DT Article DE ceramic matrix composites; 2D woven composite; monotonic loading; fatigue loading; tension-compression cycling; room and elevated temperatures ID HIGH-TEMPERATURE; FREQUENCY; CREEP AB This study characterized a woven fabric reinforced ceramic matrix composite, Nextel(TM) 312/Blackglas(TM), under monotonic and fatigue loading conditions at room and elevated (760 degreesC) temperatures in order: (1) to investigate monotonic tensile and compressive loading behavior at room and elevated temperatures, (2) to establish the fatigue life diagrams (S-N curves) with tensile and zero mean load under low frequency (0.1 Hz) cycling condition at room and elevated temperatures, and (3) to investigate damage mechanisms and failure modes under monotonic and fatigue loading conditions. Fatigue lives under tension-compression cycling were much longer than those under tension-tension cycling at a given stress range for both room and elevated temperatures. However, fatigue lives under tension-compression cycling were much shorter than those under tension-tension cycling for a given maximum stress level at room temperature, but lives were about equal under these two loading conditions for a given maximum stress level at elevated temperatures. Further, fatigue lives were much shorter at elevated temperature than their counterparts at room temperature for a given stress range or for a given maximum stress level under the both tension-tension and tension-compression cycling conditions. C1 USAF, Res Lab, Mat & Mfg Directorate, AFIT ENY, Wright Patterson AFB, OH 45433 USA. USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Mall, S (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFIT ENY, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 17 TC 1 Z9 1 U1 0 U2 3 PU VSP BV PI ZEIST PA PO BOX 346, 3700 AH ZEIST, NETHERLANDS SN 0924-3046 J9 ADV COMPOS MATER JI Adv. Compos. Mater. PY 2001 VL 10 IS 1 BP 1 EP 15 DI 10.1163/15685510152546321 PG 15 WC Materials Science, Composites SC Materials Science GA 474QN UT WOS:000171118500001 ER PT J AU Crasto, AS Kim, RY Mistretta, JP AF Crasto, AS Kim, RY Mistretta, JP TI The application of composites for the rehabilitation of concrete bridge infrastructure SO ADVANCED COMPOSITE MATERIALS LA English DT Article; Proceedings Paper CT 9th United State/Japan Conference on Composite Materials CY JUL 03-04, 2000 CL MISHIMA, JAPAN SP Japan Soc Composite Mat, Amer Soc Composite DE concrete beam; rehabilitation; composite plate and rod; stiffening; strengthening; bending moment; deflection AB This paper describes recent efforts at the Materials & Manufacturing Directorate of the US Air Force Research Laboratory (AFRL) to demonstrate the feasibility of rehabilitating concrete beams in bridge decks with fiber-reinforced composites. Early work in this program built on the success in Europe in repairing bridge beams by bonding thin composite plates to their lower surfaces, Materials and processes were appropriately selected, validated with flexural tests on scaled-down and full-sized concrete beams and implemented in a vehicular bridge in the field. The durability of this rehabilitation scheme was evaluated from actual exposure in service. From the results emerged a novel concept: the use of composite rods (instead of plates), embedded in longitudinal grooves in the lower face of the beam to improve flexural strength and stiffness. In addition to improved affordability, convenience and performance, this approach provides the unique ability to rehabilitate deteriorated concrete beams, in service, without the necessity of strengthening or otherwise preparing the concrete. The results demonstrate the viability of this repair scheme. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Kim, RY (reprint author), Univ Dayton, Res Inst, Dayton, OH 45469 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU VSP BV PI ZEIST PA PO BOX 346, 3700 AH ZEIST, NETHERLANDS SN 0924-3046 J9 ADV COMPOS MATER JI Adv. Compos. Mater. PY 2001 VL 10 IS 2-3 BP 147 EP 157 DI 10.1163/156855101753396627 PG 11 WC Materials Science, Composites SC Materials Science GA 522AL UT WOS:000173873500007 ER PT S AU Hughes, DH Hedges, RA Suter, BW AF Hughes, DH Hedges, RA Suter, BW BE Luk, FT TI Equilibria in transition SO ADVANCED SIGNAL PROCESSING ALGORITHMS, ARCHITECTURES, AND IMPLEMENTATIONS XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Signal Processing Algorithms, Architectures, and Implementations XI CY AUG 01-03, 2001 CL SAN DIEGO, CA SP SPIE DE nonstationary signals; catastrophe theory; nonlinear forces; time-frequency densities; transient motion; instantaneous equilibrium AB We investigate the motion of a single particle in transition from one equilibrium state to another via time-frequency analysis. Between quasi-stationary regimes a sudden change of state occurs, and we show that the Cohen-Lee local variance tracks well this highly nonstationary, sudden transient motion. In the quasi-stationary regime, instantaneous equilibria yield simple harmonic motion when the amplitude of oscillation is sufficiently small. Nonlinear effects induce harmonic generation for larger amplitude oscillations. C1 USAF, Res Lab, Ctr Integrated Transmiss & Exploitat, Rome, NY 13441 USA. RP Hughes, DH (reprint author), USAF, Res Lab, Ctr Integrated Transmiss & Exploitat, 525 Brooks Rd, Rome, NY 13441 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4188-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4474 BP 77 EP 85 AR UNSP 4474-61 DI 10.1117/12.448689 PG 9 WC Engineering, Electrical & Electronic; Mathematics, Applied; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Mathematics; Imaging Science & Photographic Technology; Telecommunications GA BU13T UT WOS:000175127100009 ER PT S AU Bonneau, RJ AF Bonneau, RJ BE Luk, FT TI Two dimensional phase integration for radar image formation SO ADVANCED SIGNAL PROCESSING ALGORITHMS, ARCHITECTURES, AND IMPLEMENTATIONS XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Advanced Signal Processing Algorithms, Architectures, and Implementations XI CY AUG 01-03, 2001 CL SAN DIEGO, CA SP SPIE DE radar; image; phase integration; wavelet; detection AB Radar imaging traditionally requires extremely large computational resources in order to coherently process data into an image due to the large number of data samples in high bandwidth radars. We propose a methodology to achieve high range and cross range resolution by pre-detection followed by phase integration in the wavelet domain in order to significantly reduce the bandwidth necessary and the computational load of the coherent phase processing. We will then compare this process to FFT based phase integration in terms of computational complexity and show simulated results. C1 USAF, Res Lab, SNRT, Washington, DC 20330 USA. RP Bonneau, RJ (reprint author), USAF, Res Lab, SNRT, Washington, DC 20330 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 0-8194-4188-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4474 BP 306 EP 310 AR UNSP 4474-37 DI 10.1117/12.448662 PG 5 WC Engineering, Electrical & Electronic; Mathematics, Applied; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Mathematics; Imaging Science & Photographic Technology; Telecommunications GA BU13T UT WOS:000175127100033 ER PT S AU Voevodin, NN Balbyshev, VN Vreugdenhil, AJ Johnson, JA Donley, MS AF Voevodin, NN Balbyshev, VN Vreugdenhil, AJ Johnson, JA Donley, MS BE Falcone, A Nelson, KM Albers, R Avery, WB TI Evaluation of corrosion protection performance of sol-gel surface treatments on AA2024-T3 SO ADVANCING AFFORDABLE MATERIALS TECHNOLOGY SE INTERNATIONAL SAMPE TECHNICAL CONFERENCE SERIES LA English DT Proceedings Paper CT 33rd International SAMPE Technical Conference CY NOV 05-08, 2001 CL SEATTLE, WA SP Soc Advancement Mat & Process Engn, Seattle Chapter DE corrosion; sol gel processing; coatings ID ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY AB The Air Force requires development of environmentally compliant aircraft coating systems that perform adequately in terms of corrosion protection. Current Air Force corrosion inhibitor paint chemistry relies heavily on the use of Cr(VI) compounds in the form of strontium or barium chromate, which are incorporated into both the surface pretreatment and the primers, These corrosion inhibitor systems are very effective, but are known carcinogens and therefore must be eliminated, To address this problem, sol-gel based surface treatments are being investigated as a potential replacement for the current chromate-based approach. Surface modifications based on the conventional epoxy-zirconate sol-gel and the newly developed self-assembled nanophase particle (SNAP) silicon sol-gel coatings have been investigated. The formation of SNAP sol-gel relies on aqueous solution processes to generate nanoscale particles with an inorganic core and an organic exterior. SNAP coatings provide functionality for bonding to appropriate substrates and tailorable chemistry for interaction with subsequent polymer layers. Adhesion and barrier properties of the SNAP sol-gel surface treatment have been compared to the corrosion protection afforded by conventional coating systems. It has been demonstrated in a 2000 hr salt spray test that coating systems with SNAP surface treatment perform as well as systems with Alodine(TM) pretreatment and a chromated primer. Superior adhesion and corrosion protection characteristics make SNAP surface treatment a promising environmentally benign alternative to chromate pretreatments. C1 USAF, Res Lab, Mat & Mfg Directorate, Nonstruct Mat Branch, Wright Patterson AFB, OH 45433 USA. RP Voevodin, NN (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Nonstruct Mat Branch, Bldg 654, Wright Patterson AFB, OH 45433 USA. NR 15 TC 0 Z9 0 U1 1 U2 3 PU SOC ADVANCEMENT MATERIAL & PROCESS ENGINEERING PI COVINA PA 1161 PARKVIEW DR,, COVINA, CA 91724-3748 USA SN 0892-2624 BN 0-938994-91-3 J9 INT SAMPE TECH CONF PY 2001 VL 33 BP 983 EP 997 PG 15 WC Materials Science, Characterization & Testing; Materials Science, Composites SC Materials Science GA BT76Y UT WOS:000173976200087 ER PT J AU Naboulsi, SK Palazotto, AN AF Naboulsi, SK Palazotto, AN TI Thermomicromechanical damage in composites SO AIAA JOURNAL LA English DT Article ID MECHANICS; FAILURE AB A thermomicromechanical model of failure is presented based on thermodynamic principles, that is, using the balancing laws: the conservation of momentum and the first and second laws of thermodynamics. The model is oriented toward damage initiation and damage progression in a composite structure under an intense pressure shock wave, A micromechanical damage approach is considered where three damage modes are modeled tensile damage, shear damage, and interphase or material mismatch discontinuity between the composite's matrix and fiber. A homogenization technique is incorporated in the development to simplify the representation of the nonhomogeneous material. A summary of the equations for the thermomicromechanical model of failure is presented where a damage parameter D is defined to characterize the lamina's damage based on energy dissipation. Numerical analyses are presented to demonstrate the model characterization to damage. C1 USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. RP Naboulsi, SK (reprint author), USAF, Inst Technol, Dept Aeronaut & Astronaut, Wright Patterson AFB, OH 45433 USA. NR 42 TC 5 Z9 5 U1 0 U2 1 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 JAN PY 2001 VL 39 IS 1 BP 141 EP 152 PG 12 WC Engineering, Aerospace SC Engineering GA 390XX UT WOS:000166326000018 ER PT J AU Birman, V Byrd, LW AF Birman, V Byrd, LW TI Natural frequencies of cross-ply laminated panels with matrix cracks SO AIAA JOURNAL LA English DT Article ID COMPOSITES; PLATES C1 Univ Missouri, Engn Educ Ctr, St Louis, MO 63121 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Birman, V (reprint author), Univ Missouri, Engn Educ Ctr, 8001 Nat Bridge Rd, St Louis, MO 63121 USA. NR 12 TC 1 Z9 1 U1 1 U2 2 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD JAN PY 2001 VL 39 IS 1 BP 190 EP 193 DI 10.2514/2.1291 PG 4 WC Engineering, Aerospace SC Engineering GA 390XX UT WOS:000166326000026 ER PT J AU Nelson, TJ Wheeler, TH Mustard, TS AF Nelson, TJ Wheeler, TH Mustard, TS TI Workplace protection factors-supplied air hood SO AIHAJ LA English DT Article DE ANSI Z88.2; respirators; strontium chromate; workplace protection factor ID PURIFYING RESPIRATORS AB Several organizations list assigned protection factors. For supplied air hoods, the value of the assigned protection factors varies from <10 to 2000 depending on the organization. Workplace protection factors (WPFs) of a supplied air hood were measured during aircraft sanding and painting operations on several types of aircraft to evaluate whether the American National Standard Z88.2 (1992) assigned protection factor of 1000 was realistic. The primary contaminant during these activities is strontium chromate. Samples collected inside the hood show that employees during sanding and painting operations were not exposed to strontium. The respirator performed adequately. This study is consistent with other simulated and WPF studies in that the ANSI Z88.2 WPF of 1000 is supported. C1 NIHS Inc, Ardentown, DE USA. 72 AMDS SGPB, Tinker AFB, OK 73145 USA. Parsons Engn Sci Inc, Denver, CO 80290 USA. RP Nelson, TJ (reprint author), NIHS Inc, 2401 E Mall, Ardentown, DE USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU AMER INDUSTRIAL HYGIENE ASSOC PI FAIRFAX PA 2700 PROSPERITY AVE #250, FAIRFAX, VA 22031-4307 USA SN 1529-8663 J9 AIHAJ JI AIHAJ PD JAN-FEB PY 2001 VL 62 IS 1 BP 96 EP 99 DI 10.1080/15298660108984615 PG 4 WC Environmental Sciences; Public, Environmental & Occupational Health SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health GA 404DU UT WOS:000167082800013 PM 11258874 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 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 Jeong, LS BE Shen, SS Descour, MR TI MODTRAN4, version 2: Radiative transfer modeling SO ALGORITHMS FOR MULTISPECTRAL, HYPERSPECTRAL AND ULTRASPECTRAL IMAGERY VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Multispectral, Hyperspectral, and Ultraspectral Imagery VII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE MODTRAN; remote sensing; surface albedos; aerosols; multiple scattering; HITRAN ID MULTIPLE-SCATTERING; ALGORITHM; FASCODE AB MODTRAN4, version 2, will soon be released by the U.S. Air Force Geophysics Laboratory; it is an extension of the MODTRAN4, vl, atmospheric transmission, radiance and flux model developed jointly by the Air Force Research Laboratory/Space Vehicles Directorate (AFRL/VS) and Spectral Sciences, Inc. The primary accuracy improvements in MODTRAN4 remain those previously published: (1) the multiple scattering correlated-k approach to describe the statistically expected transmittance properties for each spectral bin and atmospheric layer, and (2) the Beer-Lambert formulation that improves the treatment of path inhomogeneities. Version 2 code enhancements are expected to include: pressure-dependent atmospheric profile input, as an auxiliary where the hydrostatic equation is integrated explicitly to compute the altitudes, CFC cross-sections with band model parameters derived from pseudo lines, additional pressure-induced absorption features from O-2, and a new 5 cm(-1) band model option. Prior code enhancements include the incorporation of solar azimuth dependence in the DISORT-based multiple scattering model, the introduction of surface BRDF (Bi-directional Radiance Distribution Functions) models and a 15 cm(-1) band model for improved computational speed. Last year's changes to the HITRAN database, relevant to the 0.94 and 1.13 um. bands of water vapor, have been maintained in the MODTRAN4, v2 databases. C1 USAF, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Anderson, GP (reprint author), USAF, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. NR 16 TC 13 Z9 13 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 0-8194-4076-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4381 BP 455 EP 459 DI 10.1117/12.437035 PG 5 WC Engineering, Electrical & Electronic; Optics; Imaging Science & Photographic Technology; Spectroscopy SC Engineering; Optics; Imaging Science & Photographic Technology; Spectroscopy GA BT24W UT WOS:000172421200045 ER PT S AU Wilson, KS Ryan, PA Minardi, MJ AF Wilson, KS Ryan, PA Minardi, MJ BE Zelnio, EG TI Phase-history data collection for synthetic scene modeling applications SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE synthetic aperture radar; SAR; phase history; calibration AB Development of phase history calibration techniques is important for improving Synthetic Aperture Radar (SAR) scene modeling capabilities. Image data of complex scene settings is used for clutter database construction, and the resulting databases are used in conjunction with synthetic radar predictions of complex targets to predict synthetic SAR imagery. The current method of trihedral calibration is typically performed after image formation, using a ratiometric technique, which is highly dependent on calibration target position and orientation and ground truth accuracy. As part of a recent SAR research data collection, measurements were made on a calibration-grade, 6-meter diameter top hat in both a homogeneous scene and with controlled obscuration and layover conditions. This paper will discuss phase-history calibration target design and scenario design to support obscuration and layover studies. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Wilson, KS (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 112 EP 119 DI 10.1117/12.438201 PG 8 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500012 ER PT S AU Diemunsch, J AF Diemunsch, J BE Zelnio, EG TI Continuous identification technology SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE AB The Air Force Research Laboratory's Sensor Directorate is developing the next step in target recognition, a continuous identification capability. This capability consists of a wide range of algorithms, sensor modes and technologies that work in concert to contribute to the overall goal of identification of moving as well as stationary targets. Three major pieces of this emerging capability are stationary identification, correlation of this information with tracks and the moving target recognition technologies. Although a brief discussion of each of these pieces will be provided in this paper, the concentration will be on the actual algorithms and technologies of the moving target recognition exploiting High Range Resolution (HRR) radar mode and how this complements Ground Moving Target Indication (GMTI) tracking and Synthetic Aperture Radar (SAR) Automatic Target Recognition (ATR). This paper will expand on the overall continuous ID vision, work performed under several efforts, new sources of HRR data, and how this data will push the state of the art. The advantages of continuous ID should be obvious to the warfighter in many dimensions. As a command and control structure it is very difficult to identify and target time critical targets especially when the identification process is limited to stationary targets. These technologies will provide a wider range of targeting options so the enemy has no sanctuary in moving, setting up and in hiding. C1 AFRL, SNAA, Wright Patterson AFB, OH 45433 USA. RP Diemunsch, J (reprint author), AFRL, SNAA, Wright Patterson AFB, OH 45433 USA. NR 4 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 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 153 EP 163 DI 10.1117/12.438206 PG 11 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500016 ER PT S AU Mitra, AK Lewis, TL AF Mitra, AK Lewis, TL BE Zelnio, EG TI Spectral analysis of high frequency SAR data SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE SAR; target detection; spectral analysis; phase spectrum; bispectrum AB A number of spectral feature computations for purposes of discriminating military targets from clutter are currently under investigation within the Radar Branch at the Air Force Research Laboratory. Results from a comparative performance analysis of these features are reported. The development and analysis of spectral phase computations are of particular interest since, for some "hard clutter" environments, the use of amplitude-based discriminants does not generate a sufficiently low false alarm rate. These phase computations are based on the analysis of the Fourier phase function. analysis of the phase spectral density, and analysis of the bispectrum. Additional spectral features, such as features based on angular diversity, are also included within the scope of this investigation. The data for this investigation is comprised of some SAR images and image chips that were collected and generated under the DARPA/Air Force Moving and Stationary Target Acquisition and Recognition (MSTAR) Program. C1 ARFL, SNRR, Wright Patterson AFB, OH 45433 USA. RP Mitra, AK (reprint author), ARFL, SNRR, Bldg 620,2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 212 EP 220 DI 10.1117/12.438213 PG 9 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500023 ER PT S AU Ross, TD AF Ross, TD BE Zelnio, EG TI Confidence intervals for ATR performance metrics SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE confidence intervals; binomial; Poisson; minimum length; ATR metrics; classifier evaluation ID LIMITS AB This paper describes confidence interval (CI) estimators (CIEs) for the metrics used to assess sensor exploitation algorithm (or ATR) performance. For the discrete distributions, small sample sizes and extreme outcomes encountered within ATR testing, the commonly used CIEs have limited accuracy. This paper makes available CIEs that are accurate over all conditions of interest to the ATR community. The approach is to search for CIs using an integration of the Bayesian posterior (IBP) to measure alpha (chance of the CI not containing the true value). The CIEs provided include proportion estimates based on Binomial distributions and rate estimates based on Poisson distributions. One or two-sided CIs may be selected. For two-sided CIEs, either minimal length, balanced tail probabilities, or balanced width may be selected. The CIEs' accuracies are reported based on a Monte Carlo validated integration of the posterior probability distribution and compared to the Normal approximation and "exact" (Clopper-Pearson) methods. While the IBP methods are accurate throughout, the conventional methods may realize alphas with substantial error (up to 50%). This translates to 10 to 15% error in the CI widths or to requiring 10 to 15% more samples for a given confidence level. C1 USAF, Res Lab, COMPASE Ctr, AFRL SNAT, Wright Patterson AFB, OH 45433 USA. RP Ross, TD (reprint author), USAF, Res Lab, COMPASE Ctr, AFRL SNAT, Wright Patterson AFB, OH 45433 USA. NR 11 TC 5 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 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 318 EP 329 DI 10.1117/12.438225 PG 12 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500033 ER PT S AU Power, GJ AF Power, GJ BE Zelnio, EG TI Inter-algorithmic evaluation of SAR image segmentation algorithms using multiple measures SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE segmentation; evaluation; recognition; edge detection; synthetic aperture radar; metrics; measures; segmentation quality; quality metric AB To ensure that the best possible image segmentation algorithm transitions into a real world recognition system, the segmentation algorithm must be properly evaluated. A novel approach is introduced for evaluating image segmentation algorithms. Part of the approach is to use a system of multiple measures. Using intra-algorithmic comparisons, three measures are tested on a small suite of segmented image test cases. The results from using three measures on the test suite demonstrate significant differences in the ability of the measures to distinguish segmentation quality. Another part of the novel approach is the use of an inter-algorithmic comparison which is shown to assist the evaluation of segmentation algorithms where exact edge truth is unknown such as is the case with Synthetic Aperture Radar (SAR) imagery. Results are demonstrated by using segmentation on a SAR target chip provided by the Moving and Stationary Target Acquisition and Recognition (MSTAR) program. C1 USAF, Res Lab, Target Recognit Branch, AFRL SNAT, Wright Patterson AFB, OH 45433 USA. RP Power, GJ (reprint author), USAF, Res Lab, Target Recognit Branch, AFRL SNAT, Bldg 620,2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 9 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 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 330 EP 337 DI 10.1117/12.438226 PG 8 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500034 ER PT S AU Meyer, GJ Gustafson, SC Arnold, GD AF Meyer, GJ Gustafson, SC Arnold, GD BE Zelnio, EG TI The effect of SAR resolution on target identification SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE SAR; resolution; template matching; target identification; spatial domain interpolation; MSE AB Synthetic Aperture Radar (SAR) sensors are being developed with better resolution to improve target identification, but this improvement has a significant cost. Furthermore, higher resolution corresponds to more pixels per image and, consequently, more data to process. Here, the effect of resolution on a many class target identification problem is determined using high resolution SAR data with artificially reduced resolution, a Mean-Squared Error (MSE) criterion, and template matching. It is found each increase in resolution by a factor of two increases the average MSE between a target and possible confusers by five to ten percent. Interpolating SAR images in the spatial domain to obtain artificially higher resolution images results in an average MSE that is actually much worse than the original SAR images. Increasing resolution significantly improves target identification performance while interpolating low-resolution images degrades target identification performance. C1 USAF, Res Lab, AFRL SNAT, Wright Patterson AFB, OH 45433 USA. RP Meyer, GJ (reprint author), USAF, Res Lab, AFRL SNAT, Bldg 620,2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 338 EP 345 DI 10.1117/12.438227 PG 8 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500035 ER PT S AU Velten, VJ AF Velten, VJ BE Zelnio, EG TI SAR image invariants from 3D scattering centers SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE synthetic aperture radar; scattering centers; geometric invariance; model-based vision ID ATR AB Synthetic Aperture Radar (SAR) sensors have many advantages over electro-optical sensors (EO) for target recognition applications, such as range-independent resolution and superior poor weather performance. However, the relative unavailability of SAR data to the basic research community has retarded analysis of the fundamental invariant properties of SAR sensors relative to the extensive invariant literature for EO, and in particular photographic sensors. Prior work that was reported at this conference has developed the theory of SAR invariants based on the radar scattering center concept and provided several examples of invariant configurations of SAR scatterers from measured and synthetic SAR image data. This paper will show that invariant scattering configurations can be extracted from predicted 3D data scatterer data and used to predict invariant features in measured SAR image data. C1 USAF, Res Lab, AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. RP Velten, VJ (reprint author), USAF, Res Lab, AFRL, SNAT, 2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 30 TC 4 Z9 4 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 367 EP 378 DI 10.1117/12.438230 PG 12 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500038 ER PT S AU Bryant, ML AF Bryant, ML BE Zelnio, EG TI Target signature manifold methods applied to the MSTAR dataset: Preliminary results SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE FIR; FFT; Kalman smoothing; signature manifold estimation; GLRT; Bayes; hypothesis tests AB The primary contribution of this paper is to demonstrate the application of signature manifold methods on the MSTAR data. Three manifold estimation methods (FIR, FFT, and Kalman smoothing) are compared to a baseline algorithm, MSE. The preliminary results show the manifold methods perform just as well as the baseline algorithm and have the potential for increased performance. In addition, both GLRT and Bayes hypothesis test algorithms are demonstrated for all of the manifold estimation algorithms. C1 AFRL, SNA, Wright Patterson AFB, OH 45433 USA. RP Bryant, ML (reprint author), AFRL, SNA, 2241 Av Cr, Wright Patterson AFB, OH 45433 USA. NR 6 TC 5 Z9 5 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 389 EP 394 DI 10.1117/12.438232 PG 6 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500040 ER PT S AU Arnold, DG Claypool, R Velten, V Sturtz, K AF Arnold, DG Claypool, R Velten, V Sturtz, K BE Zelnio, EG TI Synthesizing invariant 3-D rigid scattering centers SO ALGORITHMS FOR SYNTHETIC APERTURE RADAR IMAGERY VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Algorithms for Synthetic Aperture Radar Imagery VIII CY APR 16-19, 2001 CL ORLANDO, FL SP SPIE DE RADAR; ATR; invariants; recognition; reconstruction; feature extraction; scattering center ID BOUNCING RAY TECHNIQUE; CENTER REPRESENTATION AB Automatic Target Recognition (ATR) is difficult in general., but especially with RADAR. However, the problem can be greatly simplified by using the 3-D reconstruction techniques presented at SPIE1,2 the previous 2 years. Now, instead of matching seemingly random signals in I-D or 2-D, one must match scattering centers in 3-D. This method tracks scattering centers through an image collection sequence that would typically be used for SAR image formation. A major difference is that this approach naturally allows object motion (in fact the more the object moves, the better) and the resulting 'image' is a 3-D set of scattering centers! This paper discusses a preliminary study into extracting the scattering centers directly from synthetic data to build a database in anticipation of comparing the relative separability of these reconstructed scattering centers against more traditional approaches for doing ATR. C1 USAF, Res Lab, AFRL, SNAT, Wright Patterson AFB, OH 45433 USA. RP Arnold, DG (reprint author), USAF, Res Lab, AFRL, SNAT, Bldg 620,2241 Av Circle, Wright Patterson AFB, OH 45433 USA. NR 11 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 0-8194-4077-9 J9 P SOC PHOTO-OPT INS PY 2001 VL 4382 BP 395 EP 403 PG 9 WC Engineering, Electrical & Electronic; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Telecommunications GA BT21S UT WOS:000172292500041 ER PT J AU Sumrall, RW AF Sumrall, RW TI Family physicians and end-of-life care SO AMERICAN FAMILY PHYSICIAN LA English DT Letter RP Sumrall, RW (reprint author), 347 ADS SGGF, Moody AFB, GA 31699 USA. NR 2 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 JAN 1 PY 2001 VL 63 IS 1 BP 42 EP + PG 2 WC Primary Health Care; Medicine, General & Internal SC General & Internal Medicine GA 392MF UT WOS:000166414400005 PM 11195771 ER PT J AU Duch, JM Yee, J AF Duch, JM Yee, J TI Successful use of recombinant tissue plasminogen activator in a patient with relapsing peritonitis SO AMERICAN JOURNAL OF KIDNEY DISEASES LA English DT Article DE continuous ambulatory peritoneal dialysis (CAPD); peritonitis; tissue plasminogen activator (tPA) ID POSTSURGICAL ADHESIONS; DIALYSIS CATHETERS; MODEL; PREVENTION; UROKINASE; BIOFILMS; THERAPY; AGENTS; STREPTOKINASE; INFUSION AB Intraperitoneal (IP) administration of either streptokinase (SK) or urokinase (UK) has assumed an adjunctive role to antibiotic therapy in selected patients with relapsing peritonitis. In these circumstances, bacteria may be protected from antibiotics through sequestration in either fibrinous structures or biofilms within the lumen of the peritoneal dialysis (PD) catheter or the peritoneal cavity. In some cases, it appears that disruption of these sheltered microenvironments by thrombolytic agents facilitated eradication of the offending organism and obviated the need for catheter removal, replacement, or interim hemodialysis, Although IP SK has been generally well tolerated as additive therapy in relapsing peritonitis, sporadic reports of significant complications, such as abdominal pain, fever, and severe hypotension, have precluded its more widespread acceptance. The only other thrombolytic agent used in this setting, UK, is presently unavailable because of a manufacturing shortfall, Therefore, adjunctive thrombolytic therapy for relapsing peritonitis is currently restricted. To circumvent these limitations, we devised an IP tissue plasminogen activator (tPA) protocol to eliminate recurring infection in a patient undergoing chronic ambulatory PD. After a third episode of peritonitis caused by Enterobacter cloacae, treated twice previously with an adequate antibiotic regimen, we instilled 6 mt of tPA(1 mg/mL) into the PD catheter for a 2-hour dwell time. The treatment was well tolerated and, in conjunction with a third course of antibiotic therapy, has produced an infection-free interval of 8 months. (C) 2001 by the National Kidney Foundation, Inc. C1 Wright Patterson Med Ctr, Dept Med, Wright Patterson AFB, OH USA. Henry Ford Hosp, Dept Med, Detroit, MI 48202 USA. RP Duch, JM (reprint author), 74 MDOS-SGOMK,4881 Sugar Maple Dr, Wright Patterson AFB, OH 45433 USA. NR 39 TC 19 Z9 19 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 0272-6386 J9 AM J KIDNEY DIS JI Am. J. Kidney Dis. PD JAN PY 2001 VL 37 IS 1 BP 149 EP 153 DI 10.1016/S0272-6386(01)80069-X PG 5 WC Urology & Nephrology SC Urology & Nephrology GA 392QG UT WOS:000166422400021 PM 11136181 ER PT J AU Berg, GE AF Berg, GE TI Mandibular morphology and its relationship to population affinity. SO AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY LA English DT Meeting Abstract C1 USA, Cent Identificat Lab, Hickam AFB, HI 96853 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0002-9483 J9 AM J PHYS ANTHROPOL JI Am. J. Phys. Anthropol. PY 2001 SU 32 BP 38 EP 39 PG 2 WC Anthropology; Evolutionary Biology SC Anthropology; Evolutionary Biology GA 408ZX UT WOS:000167358000036 ER PT J AU Tarim, TB Ewing, RL AF Tarim, TB Ewing, RL TI Untitled SO ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING LA English DT Editorial Material C1 Texas Instruments Inc, Mixed Signal Wireless Div, Customer Owned Tooling Grp, Dallas, TX 75265 USA. USAF, Res Lab, Informat Directorate, Washington, DC 20330 USA. RP Tarim, TB (reprint author), Texas Instruments Inc, Mixed Signal Wireless Div, Customer Owned Tooling Grp, Dallas, TX 75265 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0925-1030 J9 ANALOG INTEGR CIRC S JI Analog Integr. Circuits Process. PY 2001 VL 28 IS 2 BP 139 EP 140 DI 10.1023/A:1011240614420 PG 2 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 440ZP UT WOS:000169206800001 ER PT J AU Ewing, RL Abdel-Aty-Zohdy, HS Lamont, GB AF Ewing, RL Abdel-Aty-Zohdy, HS Lamont, GB TI Multidisciplinary collaboration methodology for smart perception system-on-a-chip (SoC) SO ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING LA English DT Article DE system-on-a-chip; collaborative design; interoperability rapid prototyping; synthesis; hardware description language; biosystems; mixed signal and intelligent information processing AB Smart Perception System-on-a-Chip (SoC) systems that sense, receive, transmit, and process signals are the eyes and ears in the millennium's need of information fusion and embedded intelligence. For intelligent fusion, the process of storing and analyzing the signals acquired from these smart perception systems involves the interoperability of mixed-signal systems. Embedded intelligence involves the collaborative blending of mixed-signal systems with the multidisciplinary areas of mixed-technology domains (electrical, mechanical, optical, thermal, biochemical) and mixed-concept performance (electrical, control, digital signal processing). Collaboration of mixed-signal design differences, impose robust design challenges for multidisciplinary design methodology. Integrating application-specific signal processor cores, memory, analog and MEMs functions on the same monolithic chip of silicon involves unique collaborative design methodology in both the macro and micro arenas. Macro collaborative automation tools reflecting rapid prototyping techniques, enabling teams of designers to work together from remote sites is today's realization. Micro collaborative approaches in SoC submicron manufacturing capability, requires advances in interoperability simulation technology, hardware description languages, design analysis tools, model availability and accuracy, physical design tools, design synthesis tools, pre-developed and tested libraries of intellectual property, design advisors and test generators is tomorrow's future. At present, no micro collaborative design environment is capable of this methodology. Establishment of cross-tool interoperability design interchange standards that can bridge the gap between future and present collaborative design methodology and reduce the cost of SoC design and design time is required. C1 USAF, Inst Technol, Res Lab, Informat Directorate, Wright Patterson AFB, OH 45433 USA. Oakland Univ, Dept Elect & Syst Engn, Microelect Syst Design Lab, Rochester, MI 48309 USA. USAF, Inst Technol, Grad Sch Engn, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Ewing, RL (reprint author), USAF, Inst Technol, Res Lab, Informat Directorate, Wright Patterson AFB, OH 45433 USA. NR 8 TC 4 Z9 4 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0925-1030 J9 ANALOG INTEGR CIRC S JI Analog Integr. Circuits Process. PY 2001 VL 28 IS 2 BP 181 EP 192 DI 10.1023/A:1011294000308 PG 12 WC Computer Science, Hardware & Architecture; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 440ZP UT WOS:000169206800006 ER PT J AU Christe, KO AF Christe, KO TI A renaissance in noble gas chemistry SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION LA English DT Article ID XENON-CARBON BOND; COMPOUND; CATION C1 USAF, Res Lab, Edwards AFB, CA 93524 USA. Univ So Calif, Loker Hydrocarbon Res Inst, Los Angeles, CA 90089 USA. RP Christe, KO (reprint author), USAF, Res Lab, Edwards AFB, CA 93524 USA. RI Christe, Karl/O-4885-2014 OI Christe, Karl/0000-0003-0661-5519 NR 41 TC 89 Z9 89 U1 2 U2 18 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 1433-7851 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. PY 2001 VL 40 IS 8 BP 1419 EP + DI 10.1002/1521-3773(20010417)40:8<1419::AID-ANIE1419>3.0.CO;2-J PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 423UE UT WOS:000168195500005 ER PT J AU Moen, J Carlson, HC Milan, SE Shumilov, N Lybekk, B Sandholt, PE Lester, M AF Moen, J Carlson, HC Milan, SE Shumilov, N Lybekk, B Sandholt, PE Lester, M TI On the collocation between dayside auroral activity and coherent HF radar backscatter SO ANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES LA English DT Article DE ionosphere; ionospheric irregularities; polar ionosphere ID INTERPLANETARY MAGNETIC-FIELD; SMALL-SCALE IRREGULARITIES; LATITUDE BOUNDARY-LAYER; POLAR-CAP BOUNDARY; F-REGION; IONOSPHERIC CUSP; VELOCITY; DYNAMICS; MAGNETOPAUSE; INSTABILITY AB The 2D morphology of coherent HF radar and optical cusp aurora has been studied for conditions of predominantly southward IMF conditions, which favours low-latitude boundary layer reconnection. Despite the variability in shape of radar cusp Doppler spectra, the spectral width criterion of greater than or equal to 220 m s(-1) proves to be a robust cusp discriminator. For extended periods of well-developed radar backscatter echoes, the equatorward boundary of the greater than or equal to 220 m s(-1) spectral width enhancement lines up remarkably well with the equatorward boundary of the optical cusp aurora. The spectral width boundary is however poorly determined during development and fading of radar cusp backscatter. Closer inspection of radar Doppler profile characteristics suggests that a combination of spectral width and shape may advance boundary layer identification by HF radar. For the two December days studied the onset of radar cusp backscatter occurred within pre-existing 630.0 nm cusp auroral activity and appear to be initiated by sunrise, i.e. favourable radio wave propagation conditions had to develop. Better methods are put forward for analysing optical data, and for physical interpretation of HF radar data, and for combining these data, as applied to detection, tracking, and better understanding of dayside aurora. The broader motivation of this work is to develop wider use by the scientific community, of results of these techniques, to accelerate understanding of dynamic high-latitude boundary-processes. The contributions in this work are: (1) improved techniques of analysis of observational data, yielding meaningfully enhanced accuracy for deduced cusp locations; (2) a correspondingly more pronounced validation of correlation of boundary locations derived from the observational data set; and (3) a firmer physical rationale as to why the good correlation observed should theoretically be expected. C1 Univ Oslo, Dept Phys, N-0316 Oslo, Norway. Univ Courses Svalbard, N-9170 Longyearbyen, Norway. USAF, Res Lab, AFOSR, Arlington, VA 22203 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. RP Moen, J (reprint author), Univ Oslo, Dept Phys, POB 1048, N-0316 Oslo, Norway. NR 46 TC 50 Z9 50 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0992-7689 J9 ANN GEOPHYS-ATM HYDR JI Ann. Geophys.-Atmos. Hydrospheres Space Sci. PD JAN PY 2001 VL 18 IS 12 BP 1531 EP 1549 DI 10.1007/s005850000302 PG 19 WC Astronomy & Astrophysics; Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences SC Astronomy & Astrophysics; Geology; Meteorology & Atmospheric Sciences GA 399QH UT WOS:000166823500003 ER PT J AU Harper, DS Cox, R Summers, D Butler, W Hagan, L AF Harper, DS Cox, R Summers, D Butler, W Hagan, L TI Tobacco hypersensitivity and environmental tobacco smoke exposure in a pediatric population SO ANNALS OF ALLERGY ASTHMA & IMMUNOLOGY LA English DT Article ID SERUM IMMUNOGLOBULIN-E; IGE; ALLERGY; ATOPY AB Background: Skin testing and RAST have verified the existence of tobacco-specific IgE. However, published studies report conflicting results concerning the clinical significance of tobacco IgE. Previous studies have not focused on the role of environmental tobacco smoke (ETS) as it relates to tobacco hypersensitivity (TH) in nonsmoking children. Objective: We used nonsmoking pediatric patients to investigate the relationship between ETS and TH. Methods: Children, ages 4 to 10 years, were prospectively enrolled. ETS exposure and smoke-triggered symptoms were recorded by questionnaire and physician history. Patients were given a skin test (ST) with a panel of aeroallergens plus tobacco extract. A ST reaction to at least one aeroallergen classified a patient as atopic; a ST reaction to tobacco classified a patient as TH. Results: We enrolled 170 patients, mean age 7.2 years. We found 58 (34%) patients reported routine exposure to ETS and 78 (46%) patients reported ETS-induced symptoms. We found 121 (71%) atopic patients and 61 (36%) TH patients. TH was more common in atopic patients (r < .0001) and those routinely exposed to ETS (P < .05). However, TH failed to predict ETS-induced symptoms in either atopic or non-atopic patients (PPV = 0.40, NPV = 0.69). Conclusions: We evaluated the clinical significance of TH in a nonsmoking patient population related to ETS exposure, We concluded that although TH is statistically related to atopy and ETS exposure, the low predictive values of skin testing fur TH limit its clinical usefulness. C1 Wilford Hall Med Ctr, Med Wing 59th, Lackland AFB, TX 78236 USA. Grp Hlth Cooperat Puget Sound, Seattle, WA 98121 USA. RP Cox, R (reprint author), Wilford Hall Med Ctr, Med Wing 59th, 59 MDW-MMIA,2200 Bergquist Dr,Suite 1, Lackland AFB, TX 78236 USA. NR 17 TC 7 Z9 7 U1 0 U2 0 PU AMER COLL ALLERGY ASTHMA IMMUNOLOGY PI ARLINGTON HTS PA 85 WEST ALGONQUIN RD SUITE 550, ARLINGTON HTS, IL 60005 USA SN 1081-1206 J9 ANN ALLERG ASTHMA IM JI Ann. Allergy Asthma Immunol. PD JAN PY 2001 VL 86 IS 1 BP 59 EP 61 PG 3 WC Allergy; Immunology SC Allergy; Immunology GA 395HY UT WOS:000166576000012 PM 11206241 ER PT S AU Oxley, ME Carter, MA AF Oxley, ME Carter, MA BE Priddy, KL Keller, PE Angeline, PJ TI Capability measures of artificial neural network architectures based on soft shattering SO APPLICATIONS AND SCIENCE OF COMPUTATIONAL INTELLIGENCE IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications and Science of Computational Intelligence IV CY APR 17-18, 2001 CL ORLANDO, FL SP SPIE DE artificial neural network; capability measure; V-C dimension; soft shattering AB Measures of an artificial neural network (ANN) capability are tyically based on the Vapnik-Chernonvekis dimension and its variations. These measures may be underestimating the actual ANN's capabilities and hence overestimating the required number of examples for learning. This is caused by relying on a single invariant description of the problem set, which, in this case is cardinality, and requiring worst case geometric arrangements and colorings. A capability measure of an ANN is (usually) related to the desired characteristics of the problem sets. The mathematical framework has been established in which to express other desired invariant descriptors of a capability measure (e.g., V-C dimension uses cardinality). A new invariants is defined on the problem space that softens the (hard) shattering constraint and yields a new capability measure of ANNs. The theory is given as well as examples that demostrate this new measure. C1 USAF, Inst Technol, Dept Math & Stat, Wright Patterson AFB, OH 45433 USA. RP Oxley, ME (reprint author), USAF, Inst Technol, Dept Math & Stat, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4085-X J9 P SOC PHOTO-OPT INS PY 2001 VL 4390 BP 44 EP 52 DI 10.1117/12.421183 PG 9 WC Computer Science, Artificial Intelligence; Computer Science, Theory & Methods; Robotics SC Computer Science; Robotics GA BS34C UT WOS:000169530600005 ER PT S AU Magnus, AL Oxley, ME AF Magnus, AL Oxley, ME BE Boscacchi, B Fogel, DB Bezdek, JC TI The theory of confusion SO APPLICATIONS AND SCIENCE OF NEURAL NETWORKS, FUZZY SYSTEMS, AND EVOLUTIONARY COMPUTATION IV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 4th International Conference on Applications and Science of Neural Networks, Fuzzy Systems, and Evolutionary Computation CY JUL 31-AUG 02, 2001 CL SAN DIEGO, CA SP SPIE AB Given a classifier, presently we use a confusion matrix to quantify how much the classifier deviates from truth based upon training data. Shortcomings to this limited application of the confusion matrix are that (1) it does not communicate data trends in feature space, for example where errors congregate, and (2) the truth mapping is largely unknown except for a small, potentially biased sample set. In practice, one does not have truth but has to rely on an expert's opinion. We propose the mathematical theory of confusion comparing and contrasting the opinions of two experts (i.e., two classifiers). This theory has advantages over traditional confusion matrices in that it provides a capability for expressing classification confidence over ALL of feature space, not just at sampled truth. This theory quantifies different types of confusion between classifiers and yields a region of feature space where confusion occurs. An example using Artificial Neural Networks will be given. C1 USAF, Res Lab, IFTD, Rome, NY 13441 USA. RP Magnus, AL (reprint author), USAF, Res Lab, IFTD, 525 Brooks Rd, Rome, NY 13441 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4193-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4479 BP 105 EP 116 DI 10.1117/12.448337 PG 12 WC Computer Science, Artificial Intelligence SC Computer Science GA BT90S UT WOS:000174396300013 ER PT S AU Gustafson, SC Meyer, GJ AF Gustafson, SC Meyer, GJ BE Nasrabadi, NM Katsaggelos, AK TI Spline-based neural networks for digital image interpolation SO APPLICATIONS OF ARTIFICIAL NEURAL NETWORKS IN IMAGE PROCESSING VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications of Artificial Neural Networks in Image Processing VI CY JAN 25-26, 2001 CL SAN JOSE, CA SP Soc Imaging Sci & Technol, SPIE AB Adaptive spline interpolation (which is equivalent to the use of a type of radial basis function neural network) is investigated for digital image interpolation (i.e., for resolution enhancement). Test image results indicate that adaptive spline interpolation of a low-resolution image is superior to non-adaptive interpolation if the adjustable parameters are chosen to yield the best match to a known object in a corresponding high-resolution image. C1 USAF, Inst Technol, ENG, Wright Patterson AFB, OH 45433 USA. RP Gustafson, SC (reprint author), USAF, Inst Technol, ENG, Wright Patterson AFB, OH 45433 USA. NR 3 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 0-8194-3983-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4305 BP 39 EP 44 DI 10.1117/12.420942 PG 6 WC Computer Science, Artificial Intelligence; Optics; Imaging Science & Photographic Technology SC Computer Science; Optics; Imaging Science & Photographic Technology GA BS27A UT WOS:000169322700005 ER PT S AU Brown, RK Claypoole, RL AF Brown, RK Claypoole, RL BE Tescher, AG TI Image registration using redundant wavelet transforms SO APPLICATIONS OF DIGITAL IMAGE PROCESSING XXIV SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Applications of Digital Image Processing XXIV CY JUL 31-AUG 03, 2001 CL SAN DIEGO, CA SP SPIE DE image registration; wavelet transform; shift-invariant wavelet transform; rotation-invariant wavelet transform; masking ID PARALLEL REGISTRATION; TRANSLATION; SENSITIVITY AB Imagery is collected much faster and in significantly greater quantities today compared to a few years ago. Accurate registration of this imagery is vital for comparing the similarities and differences between multiple images. Image registration is a significant component in computer vision and other pattern recognition problems, medical applications such as Medical Resonance Images (MRI) and Positron Emission Tomography (PET), remotely sensed data for target location and identification, and super-resolution algorithms. Since human analysis is tedious and error prone for large data sets, we require an automatic, efficient, robust, and accurate method to register images. Wavelet transforms have proven useful for a variety of signal and image processing tasks. In our research, we present a fundamentally new wavelet-based registration algorithm utilizing redundant transforms and a masking process to suppress the adverse effects of noise and improve processing efficiency. The shift-invariant wavelet transform is applied in translation estimation and a new rotation-invariant polar wavelet transform is effectively utilized in rotation estimation. We demonstrate the robustness of these redundant wavelet transforms for the registration of two images (i.e., translating or rotating an input image to a reference image), but extensions to larger data sets are feasible. We compare the registration accuracy of our redundant wavelet transforms to the "critically sampled" discrete wavelet transform using the Daubechies (7,9) wavelet to illustrate the power of our algorithm in the presence of significant additive white Gaussian noise and strongly translated or rotated images. The views expressed in this article are those of the authors and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the U. S. Government. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. EM rick.brown@ieee.org; claypooler@alum.mit.edu NR 23 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 0-8194-4186-4 J9 PROC SPIE PY 2001 VL 4472 BP 30 EP 41 DI 10.1117/12.449794 PG 4 WC Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BT90R UT WOS:000174396200004 ER PT S AU Mendenhall, MJ Claypoole, RL AF Mendenhall, MJ Claypoole, RL BE Tescher, AG TI Wavelet-based audio embedding and audio/video compression SO APPLICATIONS OF DIGITAL IMAGE PROCESSING XXIV SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Applications of Digital Image Processing XXIV CY JUL 31-AUG 03, 2001 CL SAN DIEGO, CA SP SPIE DE watermarking; compression; embedding; bit-plane coding; index coding; entropy coding; discrete wavelet transform ID MULTIRESOLUTION WATERMARKING; DIGITAL WATERMARKING; IMAGES AB Watermarking, traditionally used for copyright protection, is used in a new and exciting way. An efficient wavelet-based watermarking technique embeds audio information into a video signal. Several effective compression techniques are applied to compress the resulting audio/video signal in an embedded fashion. This wavelet-based compression algorithm incorporates bit-plane coding, index coding, and Huffman coding. To demonstrate the potential of this audio embedding and audio/video compression algorithm, we embed an audio signal into a video signal and then compress. Results show that overall compression rates of 15:1 can be achieved. The video signal is reconstructed with a median PSNR of nearly 33 dB. Finally, the audio signal is extracted from the compressed audio/video signal without error. The views expressed in this article are those of the authors and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the U. S. Government. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. RP Mendenhall, MJ (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 20 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 0-8194-4186-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4472 BP 413 EP 423 DI 10.1117/12.449771 PG 5 WC Computer Science, Software Engineering; Computer Science, Theory & Methods; Engineering, Electrical & Electronic; Optics SC Computer Science; Engineering; Optics GA BT90R UT WOS:000174396200038 ER PT J AU Hirota, TK Young, RJ Warschaw, KE AF Hirota, TK Young, RJ Warschaw, KE TI A 64-year-old man with glossitis - Herpes simplex virus (HSV) glossitis SO ARCHIVES OF DERMATOLOGY LA English DT Article ID GEOMETRIC GLOSSITIS; INFECTION C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Baylor Coll Med, Houston, TX 77030 USA. RP Hirota, TK (reprint author), Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. NR 10 TC 0 Z9 0 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 JAN PY 2001 VL 137 IS 1 BP 87 EP + PG 2 WC Dermatology SC Dermatology GA 393EZ UT WOS:000166457400016 ER PT J AU Rispoli, DM Sanders, TG Miller, MD Morrison, WB AF Rispoli, DM Sanders, TG Miller, MD Morrison, WB TI Magnetic resonance imaging at different time periods following hamstring harvest for anterior cruciate ligament reconstruction SO ARTHROSCOPY LA English DT Article DE anterior cruciate ligament; surgery; magnetic resonance imaging; hamstring tendons ID GRACILIS TENDONS; PATELLAR TENDON; SEMITENDINOSUS; SURGERY; GRAFT; FRACTURE AB Purpose: The purpose of this study was to evaluate the magnetic resonance imaging (MRI) appearance of the hamstring graft harvest site after harvesting the hamstring tendons to reconstruct a torn anterior cruciate ligament (ACL). Type of Study: Case series. Methods: We performed MRI on 21 patients who had previously undergone hamstring harvest and ACL reconstruction. Twenty of the patients (7 female and 13 male; mean age, 37 years; range, 16 to 84 years), all volunteers, were selected from a series of 45 ACL reconstructions per formed by the senior author during a 20-month period. Another patient, a 32-year-old man, underwent ACL reconstruction elsewhere 32 months before. Both the semitendinosus and gracilis tendons were harvested in all cases. All MRIs were obtained on a 1.5-T magnet and were prospectively evaluated by 2 experienced musculoskeletal radiologists who were blinded to the time interval between graft harvest and MRI. Results: Two weeks after graft harvest, MRI showed ill-defined intermediate signal on T1-weighted images and increased signal on T2-weighted images, consistent with fluid in the harvest site, with no discernable tendon. At 6 weeks, structures were seen at the level of the superior pole of the patella that had morphology and signal characteristics similar to native tendon. By 3 months, structures with normal morphology and signal characteristics were seen to the level of the joint line, and by 12 months, to the level of 1 to 3 cm above that of the tibial attachment. At 32 months, the tendons appeared on MRI to normalize to a level of 1 to 2 cm above their tibial attachment. Conclusion: Following hamstring tendon harvest, MRI demonstrates an apparent regeneration of tendons beginning proximally and extending distally over time. C1 Wilford Hall USAF Med Ctr, Dept Orthopaed, San Antonio, TX 78236 USA. Univ Texas, Hlth Sci Ctr, Dept Radiol, San Antonio, TX 78284 USA. Thomas Jefferson Univ Hosp, Dept Radiol, Philadelphia, PA 19107 USA. RP Sanders, TG (reprint author), Wilford Hall USAF Med Ctr, Dept Radiol, 759th MDTS-MTRD,2200 Bergquist Dr,STE 1, Lackland AFB, TX 78236 USA. NR 28 TC 55 Z9 60 U1 0 U2 2 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0749-8063 J9 ARTHROSCOPY JI Arthroscopy PD JAN PY 2001 VL 17 IS 1 BP 2 EP 8 DI 10.1053/jars.2001.19460 PG 7 WC Orthopedics; Surgery SC Orthopedics; Surgery GA 391WJ UT WOS:000166379000003 PM 11154359 ER PT J AU Miller, MD Sullivan, RT AF Miller, MD Sullivan, RT TI Anterior cruciate ligament reconstruction in an 84-year-old man SO ARTHROSCOPY LA English DT Article DE anterior cruciate ligament reconstruction; age AB Anterior cruciate ligament (ACL) reconstruction is typically reserved for younger patients. Several recent articles have reported expanding traditional age barriers for ACL reconstruction in patients up to 62 years old. We report a case of a successful ACL reconstruction in an active 84-year-old rancher. Physiologic age is more important than chronologic age when considering ACL reconstruction. C1 Wilford Hall USAF Med Ctr, Dept Sports Med, Lackland AFB, TX 78236 USA. Uniformed Serv Univ, Bethesda, MD USA. RP Miller, MD (reprint author), Univ Virginia Hlth Syst, Dept Orthopaed Surg, POB 800753, Charlottesville, VA 22908 USA. NR 7 TC 10 Z9 11 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0749-8063 J9 ARTHROSCOPY JI Arthroscopy PD JAN PY 2001 VL 17 IS 1 BP 70 EP 72 DI 10.1053/jars.2001.7802 PG 3 WC Orthopedics; Surgery SC Orthopedics; Surgery GA 391WJ UT WOS:000166379000015 PM 11154371 ER PT S AU Jones, JG Biggers, RR Boss, NC Busbee, JD Dempsey, DV Kozlowski, G AF Jones, JG Biggers, RR Boss, NC Busbee, JD Dempsey, DV Kozlowski, G BE Rudas, IJ Tar, JK TI Image processing plume fluence for process control of pulsed-laser thin-film depositions SO ARTIFICIAL INTELLIGENCE IN REAL-TIME CONTROL 2000 SE IFAC SYMPOSIA SERIES LA English DT Proceedings Paper CT 9th IFAC Symposium on Artificial Intelligence in Real-Time Control (AIRTC-2000) CY OCT 02-04, 2000 CL BUDAPEST, HUNGARY SP Int Federat Automat Control, Budapest Polytechn, Minist Educ Res & Dev Div, IEEE Hungary Sect DE fuzzy control; image processing; image sensors; process control; spectroscopy ID COMPONENT AB Process control is a crucial element in all deposition techniques. It is especially elusive in the versatile and efficient deposition technique known as pulsed-laser-deposition (PLD). Image processed emissions as well as signal processed intensity measurements from the plume of a YBa2Cu3O7-x (YBCO) target are monitored in situ to determine two dimensional spatial and time-of-flight (TOF) information about plume components. Manual and fuzzy-logic based regulation of laser energy and pressure, simultaneously, based on TOF feedback have resulted in improved film quality and repeatability of the PLD thin-film depositions. The plume was imaged under various deposition conditions, including in situ changing of beam focus relative to the target surface, chamber pressure, and laser beam energy. Analysis of the collected images will provide an increased understanding of the effect of changing environmental conditions in order to improve the deposited thin film quality. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Jones, JG (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 6 TC 0 Z9 0 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI KIDLINGTON PA THE BOULEVARD, LANGFORD LANE,, KIDLINGTON OX5 1GB, OXFORD, ENGLAND SN 0962-9505 BN 0-08-043562-9 J9 IFAC SYMP SERIES PY 2001 BP 113 EP 118 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Automation & Control Systems; Computer Science; Engineering GA BT32U UT WOS:000172651000018 ER PT S AU Busbee, J Starman, L Ahmer, M Reber, J Cowan, W Maguire, J AF Busbee, J Starman, L Ahmer, M Reber, J Cowan, W Maguire, J BE Rudas, IJ Tar, JK TI Utilizing Raman spectroscopy for stress imaging in MEMS devices SO ARTIFICIAL INTELLIGENCE IN REAL-TIME CONTROL 2000 SE IFAC SYMPOSIA SERIES LA English DT Proceedings Paper CT 9th IFAC Symposium on Artificial Intelligence in Real-Time Control (AIRTC-2000) CY OCT 02-04, 2000 CL BUDAPEST, HUNGARY SP Int Federat Automat Control, Budapest Polytechn, Minist Educ Res & Dev Div, IEEE Hungary Sect ID SILICON AB MEMS devices are becoming a pervasive part of today's technology world. Currently, MEMS designers have to take residual stresses into account when designing microdevices. A more ideal state would be for the developer to design to function and to control the residual stresses to fit within designed parameters. For this to occur, methods of mapping residual stresses must be found and used. In this paper, micro-Raman spectroscopy is used to map both residual and induced stress in beam structures on silicon MEMS device. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI KIDLINGTON PA THE BOULEVARD, LANGFORD LANE,, KIDLINGTON OX5 1GB, OXFORD, ENGLAND SN 0962-9505 BN 0-08-043562-9 J9 IFAC SYMP SERIES PY 2001 BP 119 EP 122 PG 4 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Automation & Control Systems; Computer Science; Engineering GA BT32U UT WOS:000172651000019 ER PT S AU Maguire, JF LeClair, SR AF Maguire, JF LeClair, SR BE Rudas, IJ Tar, JK TI Real time control of soft adaptive interfacial matter SO ARTIFICIAL INTELLIGENCE IN REAL-TIME CONTROL 2000 SE IFAC SYMPOSIA SERIES LA English DT Proceedings Paper CT 9th IFAC Symposium on Artificial Intelligence in Real-Time Control (AIRTC-2000) CY OCT 02-04, 2000 CL BUDAPEST, HUNGARY SP Int Federat Automat Control, Budapest Polytechn, Minist Educ Res & Dev Div, IEEE Hungary Sect DE intelligent; control; system; process; models; interfaces AB The process control of fragile materials in low dimensional environments offers a number considerable materials and processing challenges. It will be appreciated, for example, that these materials may not be at the thermodynamic limit so that they are technically small systems for which the usual bulk theory either does not apply or is in need of more or less drastic revision. From the standpoint of constructing the kind of coupled chemical kinetic and transport models that are essential within the context of intelligent materials processing these aspects of soft fragile matter may have important consequences. In this paper we review and illustrate a general theory as applied to soft interfacial matter and illustrate the phenomena with some new and counterintuitive experimental results. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Maguire, JF (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI KIDLINGTON PA THE BOULEVARD, LANGFORD LANE,, KIDLINGTON OX5 1GB, OXFORD, ENGLAND SN 0962-9505 BN 0-08-043562-9 J9 IFAC SYMP SERIES PY 2001 BP 123 EP 128 PG 6 WC Automation & Control Systems; Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Automation & Control Systems; Computer Science; Engineering GA BT32U UT WOS:000172651000020 ER PT S AU Bordner, RE Wiesel, WE AF Bordner, RE Wiesel, WE BE Spencer, DB Seybold, DB Misra, AK Lisowski, RJ TI Trajectory estimation for satellite clusters SO ASTRODYNAMICS 2001, PTS I-III SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Specialists Conference CY JUL 30-AUG 02, 2001 CL QUEBEC CITY, CANADA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB The problem of tracking a satellite cluster using the periodic orbit/Floquet theory solution to relative motion can be separated into two coupled estimation problems: determining the periodic orbit, and determining the relative motion of the cluster. We have studied this problem using GPS data for the periodic orbit estimator, and both differential GPS data and timing synchronization data for the relative problem. After careful treatment of several singularities and instabilities, we have achieved accuracy of about I meter in determining the periodic reference orbit, and about 2 centimeters error in the relative motion. The relative motion estimate is very insensitive to significantly mismatched dynamics (e.g. a solar flare) that do significantly degrade the estimate of the reference orbit. C1 USAF, Inst Technol, ENY, Wright Patterson AFB, OH 45433 USA. RP Bordner, RE (reprint author), USAF, Inst Technol, ENY, 2950 P St, Wright Patterson AFB, OH 45433 USA. NR 6 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 0-87703-488-5 J9 ADV ASTRONAUT SCI PY 2001 VL 109 BP 575 EP 587 PN 1-3 PG 13 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BV23N UT WOS:000178285400036 ER PT S AU Irvin, DJ Jacques, DR AF Irvin, DJ Jacques, DR BE Spencer, DB Seybold, DB Misra, AK Lisowski, RJ TI A study of linear versus nonlinear control techniques for the reconfiguration of satellite formations SO ASTRODYNAMICS 2001, PTS I-III SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Specialists Conference CY JUL 30-AUG 02, 2001 CL QUEBEC CITY, CANADA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut AB This paper investigates several linear and nonlinear feedback control methods for satellite formation reconfigurations and compares them to a near optimal open loop, discrete-time, impulsive maneuver. The reconfigurations are done in terms of a set of relative parameters that define an orbit about the leader satellite (or center reference position if a leader satellite does not exist at the center of the formation). The purpose of the study is two-fold, to compare the control usage of continuous feedback control methods versus a discrete burn method and to determine if nonlinear control techniques offer significant improvement over more conventional linear control laws. Linear Quadratic Regulators (LQR), LQR with linearizing feedback, and State Dependent Riccati Equation (SDRE) are considered. Simulations showed that reconfigurations for small relative orbits were adequately controlled using linear techniques. C1 USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. RP Irvin, DJ (reprint author), USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 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 0-87703-488-5 J9 ADV ASTRONAUT SCI PY 2001 VL 109 BP 589 EP 608 PN 1-3 PG 20 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BV23N UT WOS:000178285400037 ER PT S AU Storz, MF AF Storz, MF BE Spencer, DB Seybold, DB Misra, AK Lisowski, RJ TI Modeling and simulation tool for the high accuracy satellite drag model SO ASTRODYNAMICS 2001, PTS I-III SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Specialists Conference CY JUL 30-AUG 02, 2001 CL QUEBEC CITY, CANADA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut ID THERMOSPHERE AB An atmospheric modeling and simulation tool designed to estimate dynamically varying features of thermospheric density is described. This tool is designed to first simulate orbital energy dissipation rates from many satellite trajectories and then input them to a thermospheric density estimation process. The thermospheric density is estimated in terms of time-varying spherical harmonic expansions of exospheric temperature (above 600 kill altitude) and inflection point temperature (at 125 kill altitude). These are the key parameters characterizing the local temperature profile in the Jacchia models. The resulting temperature profiles are linked to density through the hydrostatic and diffusion equations. The model is designed to demonstrate that density can be accurately recovered from orbital energy dissipation rates. Two parts of the modeling and simulation tool are described: the density estimation program and the thermospheric correction model it calls. This tool is designed primarily for optimization and validation of the Space Battlelab's High Accuracy Satellite Drag Model (HASDM). It will be used to refine the set of estimated density correction parameters and the set of atmospheric calibration satellites used to estimate the neutral density. The thermospheric correction model is used by both this tool and HASDM's Dynamic Calibration Atmosphere program. Tile former uses energy dissipation rates deduced from orbit determination as "observations" and the latter uses satellite tracking observations directly. If implemented for orbit determination, the density estimated either way should significantly improve the accuracy of predicted trajectories for low perigee satellites. C1 USAF, Space Command, Space Anal Ctr, Peterson AFB, CO 80914 USA. RP Storz, MF (reprint author), USAF, Space Command, Space Anal Ctr, Peterson AFB, CO 80914 USA. NR 18 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 0-87703-488-5 J9 ADV ASTRONAUT SCI PY 2001 VL 109 BP 1407 EP 1427 PN 1-3 PG 21 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BV23N UT WOS:000178285400086 ER PT S AU Marcos, FA Hoots, FR AF Marcos, FA Hoots, FR BE Spencer, DB Seybold, DB Misra, AK Lisowski, RJ TI A perspective on neutral density progress SO ASTRODYNAMICS 2001, PTS I-III SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Specialists Conference CY JUL 30-AUG 02, 2001 CL QUEBEC CITY, CANADA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut ID INCOHERENT-SCATTER DATA; THERMOSPHERIC MODEL; MASS-SPECTROMETER AB Satellite drag effects are the largest error source in determining and predicting orbits of low altitude satellites. Uncertainties in neutral density variations are the major source of satellite drag errors. After three decades of essentially no quantitative progress, the problem is being vigorously and fruitfully attacked on several fronts: data assimilation or "calibration" schemes, solar indices, space-borne measurements, and numerous relevant space weather studies. We review the operational impacts of satellite drag, the historical and forthcoming efforts of the astrodynamics community in dealing with them, and the promising future capability, when neutral density may no longer be the largest error source in determining orbits of low altitude satellites. C1 USAF, Res Lab, Space Vehicles Directorate, AFRL VSBXT, Hanscom AFB, MA 01713 USA. RP Marcos, FA (reprint author), USAF, Res Lab, Space Vehicles Directorate, AFRL VSBXT, 29 Randolph Rd, Hanscom AFB, MA 01713 USA. NR 23 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 0-87703-488-5 J9 ADV ASTRONAUT SCI PY 2001 VL 109 BP 1453 EP 1466 PN 1-3 PG 14 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BV23N UT WOS:000178285400089 ER PT S AU McLaughlin, CA Sabol, C Swank, A Burns, RD Luu, KK AF McLaughlin, CA Sabol, C Swank, A Burns, RD Luu, KK BE Spencer, DB Seybold, DB Misra, AK Lisowski, RJ TI Modeling relative position, relative velocity, and range rate for formation flying SO ASTRODYNAMICS 2001, PTS I-III SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT AAS/AIAA Astrodynamics Specialists Conference CY JUL 30-AUG 02, 2001 CL QUEBEC CITY, CANADA SP Amer Astronaut Soc, Amer Inst Aeronaut & Astronaut ID DYNAMO AB The relative position, relative velocity, and range rate evolution is examined for various formations of satellites. A simple analytical model including Earth oblateness effects for the equations of relative motion is presented. This model provides physical insight into the Earth oblateness effects that are neglected by using Hill's equations. The accuracy of the relative position, relative velocity, and range rate predictions for the analytical model are compared to realistic force modeling obtained using the Draper Semianalytical Satellite Theory for formations of varying size, inclination, and altitude. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP McLaughlin, CA (reprint author), USAF, Res Lab, 3550 Aberdeen Ave,SE, Kirtland AFB, NM 87117 USA. NR 16 TC 3 Z9 3 U1 0 U2 3 PU UNIVELT INC PI SAN DIEGO PA PO BOX 28130, SAN DIEGO, CA 92128 USA SN 1081-6003 BN 0-87703-488-5 J9 ADV ASTRONAUT SCI PY 2001 VL 109 BP 2165 EP 2186 PN 1-3 PG 22 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BV23N UT WOS:000178285400135 ER PT S AU Arnold, DG Sturtz, K Weiss, I AF Arnold, DG Sturtz, K Weiss, I BE Sadjadi, FA TI Detection and recognition in LADAR using invariants and covariants SO AUTOMATIC TARGET RECOGNITION XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 11th Conference on Automatic Target Recognition CY APR 17-20, 2001 CL ORLANDO, FL SP SPIE DE LADAR; ATR; invariants; covariants; detection; recognition AB Object-image relations (O-IRs) provide a powerful approach to performing detection and recognition with laser radar (LADAR) sensors. This paper presents the basics of O-I relations and shows how they are derived from invariants. It also explains and shows results of a computationally efficient approach applying covariants to 3-D LAD AR data. The approach is especially appealing because the detection and segmentation processes are integrated with recognition into a robust algorithm. Finally, the method provides a straightforward approach to handling articulation and multi-scale decomposition. C1 SNAT, AFRL, Dayton, OH 45433 USA. RP Arnold, DG (reprint author), SNAT, AFRL, Bldg 620,2241 Avion Circle, Dayton, OH 45433 USA. NR 13 TC 1 Z9 1 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4074-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4379 BP 25 EP 34 DI 10.1117/12.445380 PG 10 WC Computer Science, Artificial Intelligence; Remote Sensing; Optics SC Computer Science; Remote Sensing; Optics GA BT41N UT WOS:000172924200003 ER PT S AU Power, GJ AF Power, GJ BE Sadjadi, FA TI Benchtop methodology for evaluating the automatic segmentation of ladar images SO AUTOMATIC TARGET RECOGNITION XI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 11th Conference on Automatic Target Recognition CY APR 17-20, 2001 CL ORLANDO, FL SP SPIE DE segmentation; edge detection; image segmentation; evaluation; quality; metrics; measures; LADAR AB Numerous approaches to segmentation exist requiring an evaluation technique to determine the most appropriate technique to use for a specific ladar design. A benchtop evaluation methodology that uses multiple measures is used to evaluate ladar-specific image segmentation algorithms. The method uses multiple measures along with an inter-algorithmic approach that was recently introduced for evaluating Synthetic Aperture Radar (SAR) imagery. Ladar imagery is considered to be easier to segment than SAR since it generally contains less speckle and has both a range and intensity map to assist in segmentation. A system of multiple measures focuses on area, shape and edge closeness to judge the segmentation. The judgement is made on the benchtop by comparing the segmentation to supervised hand-segmented images. To demonstrate the approach, a ladar image is segmented using several segmentation approaches introduced in literature. The system of multiple measures is then demonstrated on the segmented ladar images. An interpretation of the results is given. The system of multiple measures is demonstrated as capable of evaluating a single object in the image scene or multiple objects. This paper demonstrates that the original evaluation approach designed for evaluating SAR imagery can be generalized across differing sensor modalities even though the segmentation and sensor acquisition approaches are different. C1 USAF, Res Lab, Target Recognit Branch, AFRL,SNAT, Wright Patterson AFB, OH 45433 USA. RP Power, GJ (reprint author), USAF, Res Lab, Target Recognit Branch, AFRL,SNAT, Bldg 620,2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 10 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 0-8194-4074-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4379 BP 95 EP 102 DI 10.1117/12.445355 PG 8 WC Computer Science, Artificial Intelligence; Remote Sensing; Optics SC Computer Science; Remote Sensing; Optics GA BT41N UT WOS:000172924200010 ER PT J AU Sheriff, DD Isdahl, WM Nelson, CD Werchan, PM AF Sheriff, DD Isdahl, WM Nelson, CD Werchan, PM TI Brief exposure to -Gz reduces cerebral perfusion pressure during subsequent +Gz stress in rats SO AVIATION SPACE AND ENVIRONMENTAL MEDICINE LA English DT Article DE push-pull; acceleration; G-LOC; G-tolerance; microgravity; BP; tilting ID US AIR-FORCE; HUMANS AB Introduction: In humans, +Gz exposure immediately preceded by exposure to zero or -Gz can result in unexpected incapacitation ("pushpull" effect). Our goals were to establish whether this phenomenon exists in rats and to evaluate the importance of varying the duration of -Gz exposure on magnitude of the push-pull effect on cerebral perfusion pressure. Methods: Eight conscious male rats were studied in the transition from + 5 Gr to +10 Cr imposed by centrifugation. This was done with (push-pull or without (control) 2 s exposure to -5 Gz applied using a counterbalanced design. Seven isoflurane anesthetized rats were studied in the transition from 0Gz (+1Gy) to + 1Gz imposed by tilting. This was done with (push-pu[ii or without (control) 0.5, 1, 3, or 9 a exposure to -1Gz imposed immediately prior to the transition applied using a counterbalanced designed. Results: Exposure to 2 s of -5 Gz significantly (p < 0.01) reduced carotid artery pressure in the 4(th) through a s of exposure to +10 Ct by an average of 15 mmHg compared with control. In the tilt experiments, a push-pull effect was found with mild Cr exposure (+/-1Gz) with as little as 0.5 s -Gz exposure. Varying the head-down dwell time did not alter the magnitude of the exaggerated hypotension induced by "push-pull" (p = 0.90. Conclusions: We conclude that rats express a "push-pull" effect similar to that observed in humans but that altering the duration of exposure to -Gz does not influence the magnitude of the "push-puil" effect. C1 Univ Iowa, Dept Exercise Sci, Iowa City, IA 52242 USA. USAF, Res Lab, Biodynam & Protect Div, Flight Mot Effects Branch,Brooks AFB, San Antonio, TX USA. RP Sheriff, DD (reprint author), Univ Iowa, Dept Exercise Sci, 518 FH, Iowa City, IA 52242 USA. FU NHLBI NIH HHS [HL-46314] NR 12 TC 15 Z9 18 U1 0 U2 0 PU AEROSPACE MEDICAL ASSOC PI ALEXANDRIA PA 320 S HENRY ST, ALEXANDRIA, VA 22314-3579 USA SN 0095-6562 J9 AVIAT SPACE ENVIR MD JI Aviat. Space Environ. Med. PD JAN PY 2001 VL 72 IS 1 BP 8 EP 12 PG 5 WC Public, Environmental & Occupational Health; Medicine, General & Internal; Sport Sciences SC Public, Environmental & Occupational Health; General & Internal Medicine; Sport Sciences GA 389BM UT WOS:000166218800002 PM 11194999 ER PT S AU Sharma, SK Snyder, CE Gschwender, LJ AF Sharma, SK Snyder, CE Gschwender, LJ BE Totten, GE Wedeven, LD Dickey, JR Anderson, M TI Aircraft hydraulic pump tests with advanced fire-resistant hydraulic fluids SO BENCH TESTING OF INDUSTRIAL FLUID LUBRICATION AND WEAR PROPERTIES USED IN MACHINERY APPLICATIONS SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Bench Testing of the Lubrication and Wear Properties of Industrial Fluids Used in Machinery Application CY JUN 26-27, 2000 CL SEATTLE, WA SP Amer Soc Testing & Mat, Comm D02, Amer Soc Testing & Mat, Subcomm D02 L0 DE hydraulic pumps; hydraulic fluids; viscosity; bearings; polyalphaolefin; chlorotrifluoroethylene; nonflammable hydraulic fluid AB During the development of the fire-resistant hydraulic fluids for DoD (Department of Defense) aircraft, candidate fluids were formulated and then characterized initially by various laboratory bench tests. Endurance pump tests were then conducted on the candidate fluids to validate their performance. Pump tests under accelerated conditions were conducted on three candidate fire-resistant hydraulic fluids and several candidate nonflammable hydraulic fluids, using pressure-compensated axial flow piston pumps and an instrumented, small-volume, closed-loop hydraulic test stand. Case-drain temperature and signal-noise on the pump outlet pressure and the case-drain flow provided better failure indicators than the case-drain flow. The fluids containing viscosity-index-improvers underwent large viscosity losses. No viscosity loss was observed for the fluids that did not contain the viscosity-index-improvers. Lower viscosity fluids performed as well as the higher viscosity fluids in these pump tests. However, the ball-bearing material and the heat treatment had a bigger impact on pump life. Use of an M-50 bearing in place of the AISI-52100 bearing doubled the pump life. Based upon the laboratory screening tests and the validation pump tests, the best performing fire-resistant hydraulic fluid was recommended for use in the DoD aircraft. Performance of the recommended fluid was further demonstrated in successful aircraft flight tests. Only limited hydraulic system simulator and aircraft subsystem testing has been conducted on the best-performing nonflammable hydraulic fluid candidate to date, but the performance was acceptable. C1 USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. RP Sharma, SK (reprint author), USAF, Res Lab, Mat Directorate, Wright Patterson AFB, OH 45433 USA. NR 3 TC 0 Z9 0 U1 0 U2 2 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2867-3 J9 AM SOC TEST MATER PY 2001 VL 1404 BP 168 EP 184 DI 10.1520/STP10507S PG 17 WC Engineering, Mechanical; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BS21J UT WOS:000169088500012 ER PT J AU Goltz, MN Bouwer, EJ Huang, JQ AF Goltz, MN Bouwer, EJ Huang, JQ TI Transport issues and bioremediation modeling for the in situ aerobic co-metabolism of chlorinated solvents SO BIODEGRADATION LA English DT Article DE aerobic co-metabolism; bioremediation; chlorinated solvents ID POROUS-MEDIA; COMETABOLIC DEGRADATION; INSITU BIORESTORATION; MASS-TRANSFER; SIMULATIONS; TRICHLOROETHYLENE; BIODEGRADATION; FILTRATION; BIOAVAILABILITY; GROUNDWATER AB For aerobic co-metabolism of chlorinated solvents to occur, it is necessary that oxygen, a primary substrate, and the chlorinated compound all be available to an appropriate microorganism - that is, a microorganism capable of producing the nonspecific enzyme that will promote degradation of the ontaminant while the primary substrate is aerobically metabolized. Thus, the transport processes that serve to mix the reactants are crucial in determining the rate and extent of biodegradation, particularly when considering in situ biodegradation. These transport processes intersect, at a range of scales, with the biochemical reactions. This paper reviews how the important processes contributing to aerobic co-metabolism of chlorinated solvents at different scales can be integrated into mathematical models. The application of these models to field-scale bioremediation is critically examined. It is demonstrated that modeling can be a useful tool in gaining insight into the physical, chemical, and biological processes relevant to aerobic co-metabolism, designing aerobic co-metabolic bioremediation systems, and predicting system performance. Research needs are identified that primarily relate to gaps in our current knowledge of inter-scale interactions. C1 USAF, Dept Syst & Engn Management, Wright Patterson AFB, OH 45433 USA. Johns Hopkins Univ, Dept Geog & Environm Engn, Baltimore, MD 21218 USA. RP Goltz, MN (reprint author), USAF, Dept Syst & Engn Management, 2950 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. RI Goltz, Mark/A-7394-2009; Bouwer, Edward/A-3287-2010; OI Goltz, Mark/0000-0003-3601-6453 NR 35 TC 17 Z9 18 U1 2 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0923-9820 J9 BIODEGRADATION JI Biodegradation PY 2001 VL 12 IS 2 BP 127 EP 140 DI 10.1023/A:1012005406536 PG 14 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 479GX UT WOS:000171397600004 PM 11710591 ER PT S AU Naik, RR Brott, LL Kirkpatrick, SM Stone, MO AF Naik, RR Brott, LL Kirkpatrick, SM Stone, MO BE Kish, LB TI Functional biomimetic optical devices SO BIOMEMS AND SMART NANOSTRUCTURES SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Symposium on BioMEMS and Smart Nanostructures CY DEC 17-19, 2001 CL ADELAIDE, AUSTRALIA SP SPIE, USAF, Off Sci Res, Asian Off Aerosp Res & Dev, Adelaide Univ, Ctr Biomed Engn, Def Sci & Technol Org, S Australia, Dept Ind & Trade DE biomimetics; proteins; holograms; biocatalysis; silica; thermoreception; two-photon ID HYDROGELS; SILICA AB The diversity of biological sensing and biocatalysis is astounding. A considerable effort has been directed at not only understanding the mechanism of these biological processes, but also how this activity can be maintained or duplicated in an artificial environment. We will present work on the formation of functional optical devices that convert biological responses into optical signals through changes in diffraction efficiency and reflection angle. By incorporating biomolecules into monomer systems that can be cured using a two-photon polymerization mechanism, greater spatial resolution and increased biological viability can be achieved. The polymer can be nanopatterned using ultrafast nonlinear holography to create a functional BioMEMS device. Additionally, we will discuss the characterization of the bioniolecules and the processing of the gratings that incorporate these functional proteins. This approach is a first step towards the development of a hybrid organic-inorganic composite device. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Stone, MO (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 8 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 0-8194-4320-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4590 BP 115 EP 120 DI 10.1117/12.454593 PG 6 WC Engineering, Multidisciplinary; Materials Science, Multidisciplinary; Imaging Science & Photographic Technology SC Engineering; Materials Science; Imaging Science & Photographic Technology GA BU25E UT WOS:000175475300012 ER PT B AU Nishino, SF Spain, JC AF Nishino, SF Spain, JC BE Magar, VS Johnson, G Ong, SK Leeson, A TI Identification of bottlenecks to the in situ bioremediation of dinitrotoluene SO BIOREMEDIATION OF ENERGETICS, PHENOLICS, AND POLYCYCLIC AROMATIC HYDROCARBONS SE BIOREMEDIATION SERIES LA English DT Proceedings Paper CT 6th International In Situ and On-Site Bioremediation Symposium CY JUN 04-07, 2001 CL SAN DIEGO, CA SP Battelle Mem Inst, Geomatrix Consultants Inc, IT Grp Inc, Parsons, Regenesis, USAF, Ctr Environm Excellence, USN, Fac Engn Command ID 2,6-DINITROTOLUENE; 2,4-DINITROTOLUENE AB The vadose zones beneath waste pits at Badger Army Ammunition Plant (BAAP) are heavily contaminated with 2,4-dinitrotoluene (2,4-DNT) and 2,6-dinitrotoluene (2,6-DNT) in a ratio of about 25 to 1. We conducted bench scale studies in columns and in shake flasks to determine the feasibility of in situ bioremediation at BAAP. Indigenous bacteria readily acclimated to degrade 2,4-DNT, but 2,6-DNT degradation was slow and did not occur until 2,4-DNT was removed. The onset of degradation was 6-8 weeks at 13degreesC, the in situ soil temperature. The lag period was shortened to 1-2 weeks when the experiments were conducted at 20degreesC. There was a broad pH optimum around pH 8.and degradation stopped below pH 7. The addition of 10 mM phosphate stimulated the degradation considerably, however much lower concentrations of phosphate were required in soil-free systems. In column studies conducted with contaminated soil from BAAP, initial concentrations of 14.03 g/kg and 0.55 g/kg of 2,4- and 2,6-DNT were reduced to 2-14 mg/kg and 4-12 mg/kg in inoculated columns at room temperature, and to 5-9 mg/kg and 11-98 mg/kg in inoculated columns at 13degreesC. The bench scale experiments clearly established the biological aspects of the feasibility of bioremediation of dinitrotoluene (DNT) at BAAP and a subsequent pilot scale field study based on the laboratory results has validated the findings and clearly shown that DNT can be biodegraded in situ. C1 USAF, Res Lab, Tyndall AFB, FL 32403 USA. RP Spain, JC (reprint author), USAF, Res Lab, Tyndall AFB, FL 32403 USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU BATTELLE PRESS PI COLUMBUS PA 505 KING AVE, COLUMBUS, OH 43201 USA BN 1-57477-113-2 J9 BIOREMED SER PY 2001 VL 6 IS 3 BP 59 EP 66 PG 8 WC Chemistry, Organic; Engineering, Environmental; Environmental Sciences; Toxicology SC Chemistry; Engineering; Environmental Sciences & Ecology; Toxicology GA BU12W UT WOS:000175096400008 ER PT J AU Lance, RS Freidrichs, PA Kane, C Powell, CR Pulos, E Moul, JW McLeod, DG Cornum, RL Thrasher, JB AF Lance, RS Freidrichs, PA Kane, C Powell, CR Pulos, E Moul, JW McLeod, DG Cornum, RL Thrasher, JB TI A comparison of radical retropubic with perineal prostatectomy for localized prostate cancer within the Uniformed Services Urology Research Group SO BJU INTERNATIONAL LA English DT Article DE prostatectomy; retropubic; perineal; outcome ID MARGINS AB Objective To review and compare the outcome of patients undergoing radical retropubic prostatectomy (RRP) or radical perineal prostatectomy (RPP) for clinically localized prostate cancer, Patients and methods From 1988 to 1997, 1382 men who were treated by RRP and 316 by RPP were identified from databases of the Uniformed Services Urology Research Group. The following variables were assessed; age, race, prostate-specific antigen (PSA) level before surgery, clinical stage, biopsy Gleason sum, estimated blood loss (EBL), margin-positive rate, pathological stage, biochemical recurrence rate, short and long-term complication rates, impotence and incontinence rates. To eliminate selection bias, the analysis was concentrated on pairs of patients matched by race, preoperative PSA level, clinical stage and biopsy Gleason sum. Results In the 190 matched patients there were no significant differences between the RRP and RPP groups in either organ-confined (57% vs 55%), margin-positive (39% vs 43%), or biochemical recurrence rates (12.9% vs 17.6% at a mean followup of 47.1 vs 42.9 months), respectively. The mean EEL was 1575 mi, in the RRP group and 802 mt in the RPP group (P < 0.001). The only significant difference in complication rates was a higher incidence of rectal injury in the RPP group (4.9%) than in the RRP group (none, P < 0.05). Conclusions In similar populations of patients, RPP offers equivalent organ-confirmed, margin-positive and biochemical recurrence rates to RRP, while causing significantly less blood loss. C1 Madigan Army Med Ctr, Dept Surg, Serv Urol, Tacoma, WA 98431 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. Brooke Army Med Ctr, San Antonio, TX USA. USN, San Diego Med Ctr, San Diego, CA 92152 USA. Walter Reed Army Med Ctr, Washington, DC 20307 USA. RP Lance, RS (reprint author), Madigan Army Med Ctr, Dept Surg, Serv Urol, Tacoma, WA 98431 USA. NR 16 TC 62 Z9 65 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 1464-4096 J9 BJU INT JI BJU Int. PD JAN PY 2001 VL 87 IS 1 BP 61 EP 65 DI 10.1046/j.1464-410x.2001.00023.x PG 5 WC Urology & Nephrology SC Urology & Nephrology GA 394KF UT WOS:000166522700012 PM 11121994 ER PT J AU Shaughnessy, PJ Ririe, DW Ornstein, DL Kissack, B Bickford, DJ Molina, R Lanzkron, S Bachier, C Nanez, A LeMaistre, CF AF Shaughnessy, PJ Ririe, DW Ornstein, DL Kissack, B Bickford, DJ Molina, R Lanzkron, S Bachier, C Nanez, A LeMaistre, CF TI Graft failure in a patient with systemic lupus erythematosus (SLE) treated with high-dose immunosuppression and autologous stem cell rescue SO BONE MARROW TRANSPLANTATION LA English DT Article DE systemic lupus erythematosus; high-dose immunosuppression; autologous stem cell transplantation ID BONE-MARROW TRANSPLANTATION; AUTOIMMUNE-DISEASES; IFN-GAMMA; TNF-ALPHA; GM AB A 32-year-old female with WHO grade IV, dialysis dependent, lupus nephritis was treated with high-dose immunosuppression and autologous stem cell rescue. Stem cells were mobilized with cyclophosphamide (CY) and G-CSF, and 4.07 x 10(6) CD34(+) cells/kg were obtained after CD34(+) cell selection using the CellPro column. The preparative regimen consisted of CY, and antithymocyte globulin (ATG), with methylprednisolone. After apparent primary engraftment of neutrophils on day 9, the patient developed recurrent neutropenia on day 19, She showed no evidence of engraftment by day 35, and back-up unmanipulated stem cells were given without effect. Subsequently, she received unmanipulated peripheral stem cells (2 x 10(6) CD34+ cells/kg) from an HLA-identical sibling. The patient remained pancytopenic and expired on day 62 from disseminated fungal infection. An autopsy revealed no evidence of hematopoietic recovery. Progenitor cell assays were performed with the patient's stem cells, which were collected prior to transplantation, and serum collected day 27. Morphologic examination of the patient's cell colonies grown in the presence of her serum revealed abnormal shapes and non-adherent cells. There were significantly fewer BFU-e colonies and a trend toward fewer CFU-GM colonies with the patient's cells and serum compared to normal donor cells. We concluded that a substance present in her serum mediated graft failure and prevented engraftment after additional stem cell infusions. C1 Wilford Hall USAF Med Ctr, Lackland AFB, TX 78236 USA. Arthrit Diagnost & Treatment Ctr, San Antonio, TX USA. Texas Transplant Inst, San Antonio, TX USA. RP Shaughnessy, PJ (reprint author), Wilford Hall USAF Med Ctr, 2200 Bergquist Ste 1, Lackland AFB, TX 78236 USA. NR 10 TC 14 Z9 17 U1 0 U2 3 PU NATURE PUBLISHING GROUP PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0268-3369 J9 BONE MARROW TRANSPL JI Bone Marrow Transplant. PD JAN PY 2001 VL 27 IS 2 BP 221 EP 224 DI 10.1038/sj.bmt.1702767 PG 4 WC Biophysics; Oncology; Hematology; Immunology; Transplantation SC Biophysics; Oncology; Hematology; Immunology; Transplantation GA 401RP UT WOS:000166942300019 PM 11281396 ER PT J AU Mitchell, JW Richardson, DL AF Mitchell, JW Richardson, DL TI A simplified kinetic element formulation for the rotation of a perturbed mass-asymmetric rigid body SO CELESTIAL MECHANICS & DYNAMICAL ASTRONOMY LA English DT Article; Proceedings Paper CT US/European Celestial Mechanics Workshop CY JUL 03-07, 2000 CL POZNAN, POLAND DE astronautics; satellite attitude dynamics; variation of parameters; rigid body motion; asymmetric rigid bodies ID DIFFERENTIAL-EQUATIONS; PARAMETERS APPROACH; MOTION AB Euler's equations, describing the rotation of an arbitrarily torqued mass asymmetric rigid body, are scaled using linear transformations that lead to a simplified set of first order ordinary differential equations without the explicit appearance of the principal moments of inertia. These scaled differential equations provide trivial access to an analytical solution and two constants of integration for the case of torque-free motion. Two additional representations for the third constant of integration are chosen to complete two new kinetic element sets that describe an osculating solution using the variation of parameters. The elements' physical representations are amplitudes and either angular displacement or initial time constant in the torque-free solution. These new kinetic elements lead to a considerably simplified variation of parameters solution to Euler's equations. The resulting variational equations are quite compact. To investigate error propagation behaviour of these new variational formulations in computer simulations, they are compared to the unmodified equations without kinematic coupling but under the influence of simulated gravity-gradient torques. C1 USAF, Res Lab, VACA, Wright Patterson AFB, OH 45433 USA. RP Mitchell, JW (reprint author), USAF, Res Lab, VACA, Wright Patterson AFB, OH 45433 USA. NR 15 TC 2 Z9 2 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0923-2958 J9 CELEST MECH DYN ASTR JI Celest. Mech. Dyn. Astron. PY 2001 VL 81 IS 1-2 BP 13 EP 25 DI 10.1023/A:1013338517743 PG 13 WC Astronomy & Astrophysics; Mathematics, Interdisciplinary Applications SC Astronomy & Astrophysics; Mathematics GA 518UK UT WOS:000173686100003 ER PT J AU Bardenhagen, SG Guilkey, JE Roessig, KM Brackbill, JU Witzel, WM Foster, JC AF Bardenhagen, SG Guilkey, JE Roessig, KM Brackbill, JU Witzel, WM Foster, JC TI An improved contact algorithm for the material point method and application to stress propagation in granular material SO CMES-COMPUTER MODELING IN ENGINEERING & SCIENCES LA English DT Article DE contact algorithm; material point method; wave propagation; granular material ID IN-CELL METHOD; DYNAMIC LOAD-TRANSFER; 2 DIMENSIONS; FLIP; MECHANICS; MEDIA AB Contact between deformable bodies is a difficult problem in the analysis of engineering systems. A new approach to contact has been implemented using the Material Point Method for solid mechanics, Bardenhagen, Brackbill, and Sulsky (2000a). Here two improvements to the algorithm are described. The first is to include the normal traction in the contact logic to more appropriately determine the free separation criterion. The second is to provide numerical stability by scaling the contact impulse when computational grid information is suspect, a condition which can be expected to occur occasionally as material bodies move through the computational grid. The modifications described preserve important properties of the original algorithm, namely conservation of momentum, and the use of global quantities which obviate the need for neighbor searches and result in the computational cost scaling linearly with the number of contacting bodies. The algorithm is demonstrated on several examples. Deformable body solutions compare favorably with several problems which, for rigid bodies, have analytical solutions. A much more demanding simulation of stress propagation through idealized granular material, for which high fidelity data has been obtained, is examined in detail. Excellent qualitative agreement is found for a variety of contact conditions. Important material parameters needed for more quantitative comparisons are identified. C1 Univ Utah, Dept Mech Engn, Salt Lake City, UT 84112 USA. USAF, Res Lab, Munit Directorate, Eglin AFB, FL 32542 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Utah, Dept Comp Sci, Salt Lake City, UT 84112 USA. RP Bardenhagen, SG (reprint author), Univ Utah, Dept Mech Engn, Salt Lake City, UT 84112 USA. NR 24 TC 80 Z9 83 U1 1 U2 12 PU TECH SCIENCE PRESS PI NORCROSS PA 6825 JIMMY CARTER BLVD, STE 1850, NORCROSS, GA 30071 USA SN 1526-1492 J9 CMES-COMP MODEL ENG JI CMES-Comp. Model. Eng. Sci. PY 2001 VL 2 IS 4 BP 509 EP 522 PG 14 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 498GV UT WOS:000172502200007 ER PT S AU Wodke, KE Hopper, DG AF Wodke, KE Hopper, DG BE Hopper, DG TI Status of display systems in the A-10A aircraft SO COCKPIT DISPLAYS VIII: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VIII CY APR 17-19, 2001 CL ORLANDO, FL SP SPIE DE cockpit; display; digital; avionics; interface; standard; instrument; gages; dial; indicator; monitor; meter; panel AB The report scope covers the displays and controls at the pilot's crewstation on the current model Air Force A-10A and OA-10A aircraft. Typical displays and controls are described. A description of an electronic display and an electronic control panel that have come to be of concern to the Air Force Air Combat Command (ACC) are included in the Funded Display Replacement Programs discussion. The display, which is a monochrome cathode ray tube (CRT), and the control panel were designed some 30 years ago. Thus, it is necessary to insert new technologies to maintain the capability heretofore provided by those now out of favor with the commercial sector. With this paper we begin a look at the status of displays in the A-10, which may remain in inventory until about 2030 according to current plans. From a component electronics technology perspective, such as displays, the A-10 provides several 10-year life cycle cost (LCC) planning cycles to consider multiple upgrades. Lessons learned from these three projects can be applied both to other displays in the A-10 and other aging Department of Defense (DoD) weapon systems. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Wodke, KE (reprint author), USAF, Res Lab, 2255 H St,Bldg 248,Rm 300, Wright Patterson AFB, OH 45433 USA. NR 9 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 0-8194-4057-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4362 BP 44 EP 55 AR UNSP 4362-30 DI 10.1117/12.439131 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BU10F UT WOS:000175014300004 ER PT S AU Desjardins, DD Hopper, DG AF Desjardins, DD Hopper, DG BE Hopper, DG TI Military display market segment: aircraft cockpits SO COCKPIT DISPLAYS VIII: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VIII CY APR 17-19, 2001 CL ORLANDO, FL SP SPIE DE displays; market; military; avionics; aircraft; cockpits; flight decks; fielded systems; performance parameters ID PERFORMANCE AB The military display market is analyzed in terms of one of its segments, aircraft cockpits. Parameters that require special consideration, such as luminance ranges, light emission/viewing angles, and chromaticity coordinates, are examined. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Desjardins, DD (reprint author), USAF, Res Lab, 2255 H St,Bldg 248,Rm 300, Wright Patterson AFB, OH 45433 USA. NR 39 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 0-8194-4057-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4362 BP 56 EP 73 AR UNSP 4362-04 DI 10.1117/12.439136 PG 18 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BU10F UT WOS:000175014300005 ER PT S AU French, GA Snow, MP Hopper, DG AF French, GA Snow, MP Hopper, DG BE Hopper, DG TI Display requirements for synthetic vision in the military cockpit SO COCKPIT DISPLAYS VIII: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VIII CY APR 17-19, 2001 CL ORLANDO, FL SP SPIE DE synthetic vision; aircraft cockpit; head-down display; head-up display; helmet-mounted display; human factors ID PERFORMANCE AB The term synthetic vision is used to describe combinations of sensor-based imagery (e.g., forward-looking infrared, millimeter-wave radar, light amplification or night vision systems) and imagery based on databases (e.g., digital terrain elevation data, obstacle and obstruction data. approach path data). While sensor-based imagery (often referred to as enhanced vision) has been available in military cockpits for several years, imagery based on databases (often referred to as artificial vision) has not. This paper discusses the display requirements needed for combinations of enhanced and artificial vision in military cockpits. We briefly survey current efforts to achieve synthetic vision displays in both military and civilian cockpits and the costs and benefits of these efforts. The relative advantages and disadvantages of enhanced and artificial vision are discussed within the context of current and future display capabilities, focusing on the human factors of these displays, A sampling of synthetic vision formats envisioned for use in military and civilian cockpits is presented to illustrate what might be required of head-down, head-up, and helmet-mounted displays in terms of resolution, luminance, and color. Further discussion is given to how these display requirements might be altered by aircraft mission, type, and the need to compensate for varying visibility and laser threat conditions. C1 USAF, Res Lab, Crew Syst Interface Div, Wright Patterson AFB, OH 45433 USA. RP French, GA (reprint author), USAF, Res Lab, Crew Syst Interface Div, 2210 8th St, Wright Patterson AFB, OH 45433 USA. NR 19 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4057-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4362 BP 120 EP 131 AR UNSP 4362-10 DI 10.1117/12.439111 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BU10F UT WOS:000175014300010 ER PT S AU Byrd, JC Lawrence, KM AF Byrd, JC Lawrence, KM BE Hopper, DG TI Interchangeable LCDs reduce cost and risk SO COCKPIT DISPLAYS VIII: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VIII CY APR 17-19, 2001 CL ORLANDO, FL SP SPIE DE active matrix liquid crystal display; AMLCD; display standard; commonality AB Proliferation of aircraft cockpit display types and sizes results in increased cost and risk to US Air Force, Navy and Army aircraft program. As AMLCD technology improves, modules used in current production display units become obsolete, and in most cases there is no interchangeable replacement module immediately available. This paper discusses the use of standard AMLCD modules across multiple programs as a way to prevent programs from being so dependent on obsolete or unique devices in the future. It also suggests a list of display sizes and types that are good candidates for wide application and are thus less sensitive to events like the closing of one component manufacturer. One standardization effort, presented as a success story in this paper, resulted in the same AMLCD being used on 4 diverse programs. This display module will be built at a rate of nearly 1000 per year over the next 5 years. C1 USAF, ASC ENAS, Integrated Avion Syst Branch, Wright Patterson AFB, OH 45433 USA. RP Byrd, JC (reprint author), USAF, ASC ENAS, Integrated Avion Syst Branch, 2530 Loop Rd W, 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 0-8194-4057-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4362 BP 144 EP 151 AR UNSP 4362-13 DI 10.1117/12.439114 PG 8 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BU10F UT WOS:000175014300013 ER PT S AU Meyer, FM Hopper, DG AF Meyer, FM Hopper, DG BE Hopper, DG TI Holographic polymer dispersed liquid crystal sample characterization SO COCKPIT DISPLAYS VIII: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VIII CY APR 17-19, 2001 CL ORLANDO, FL SP SPIE DE reflective paper-white display; video rate; holographically formed polymer dispersed liquid crystal; metrology ID REFLECTANCE AB Holographically formed polymer dispersed liquid crystal (HPDLC) materials have the potential to enable creation of a full motion video rate reflective display technology with excellent color, contrast, reflectance and good power efficiency. Current HPDLC display research focuses on the improvement of angular viewability and reduction of the drive voltage. Measurements of HPDLC devices have begun at AFRL to verify and expand measurements made by dpiX LLC. Specular and diffuse reflections are examined in terms of angular and spectral reflectance distributions. Presently reported measurements verify the ability of an HPDLC device to shift the reflected signal image away from the front-surface substrate specular angle (source image glare) by some 10degrees and to expand the spread of the reflected signal image (full-width-half maximum) from about 1-2degrees to 4-10degrees for a point illumination source under worst orientation conditions. Colors were stable over 20degrees of viewing angle. Potential defense applications include replacing paper in cockpits and crewstations. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Meyer, FM (reprint author), USAF, Res Lab, 2255 H St,Bldg 248 Rm 300, Wright Patterson AFB, OH 45433 USA. NR 16 TC 1 Z9 1 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 0-8194-4057-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4362 BP 255 EP 267 AR UNSP 4362-21 DI 10.1117/12.439122 PG 13 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BU10F UT WOS:000175014300023 ER PT S AU Ghrayeb, J Daniels, R AF Ghrayeb, J Daniels, R BE Hopper, DG TI Status review of field emission displays - art. no. 4362-28 SO COCKPIT DISPLAYS VIII: DISPLAYS FOR DEFENSE APPLICATIONS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Cockpit Displays VIII CY APR 17-19, 2001 CL ORLANDO, FL SP SPIE DE field emission display (FED); active matrix liquid crystal display (AMLCD); cathode ray tube (CRT); vacuum fluorescent display (VFD); high gain emission display (HGED); flat panel display (FPD); spindt cathode; thin film diamond; phosphor (high and low voltage); printable field emitters AB Cathode ray tube (CRT) technology dominates the direct view display market, Mature CRT technology for many designs is still the preferred choice. CRT manufacturers have greatly improved the size and weight of the CRT displays. High performance CRTs continue to be in great demand, however, supply have to contend with the vanishing CRT vendor syndrome. Therefore, the vanishing CRT vendor syndrome fuels the search for an alternate display technology source. Within the past 10 years, field emission display (FED) technology had gained momentum and, at one time, was considered the most viable electronic display technology candidate [to replace the CRT]. The FED community had advocated and promised many advantages over active matrix liquid crystal displays (AMLCD), electro luminescent (EL) or Plasma displays. Some observers, including potential FED manufacturers and the Department of Defense, (especially the Defense Advanced Research Project Agency (DARPA)), consider the FED entry as having leapfrog potential. Despite major investments by US manufacturers as well as Asian manufacturers, reliability and manufacturing difficulties greatly slowed down the advancement of the technology. The FED manufacturing difficulties have caused many would-be FED manufacturing participants to abandon FED research. This paper will examine the trends, which are leading this nascent technology to its downfall. FED technology was once considered to have the potential to leapfrog over AMLCD's dominance in the display industry. At the present the FED industry has suffered severe setbacks and there are very few [FED] manufacturers still pursuing research in the area. These companies have yet to deliver a display beyond the prototype stage. C1 Air Force Res Lab, Wright Patterson AFB, OH 45433 USA. RP Ghrayeb, J (reprint author), Air Force Res Lab, Bldg 248,Rm 300,2255 H St, Wright Patterson AFB, OH 45433 USA. NR 5 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 0-8194-4057-4 J9 P SOC PHOTO-OPT INS PY 2001 VL 4362 BP 319 EP 330 AR UNSP 4362-28 DI 10.1117/12.439128 PG 12 WC Engineering, Aerospace; Optics SC Engineering; Optics GA BU10F UT WOS:000175014300031 ER PT J AU Takahashi, F Schmoll, WJ Strader, EA Belovich, VM AF Takahashi, F Schmoll, WJ Strader, EA Belovich, VM TI Suppression behavior of obstruction-stabilized pool flames SO COMBUSTION SCIENCE AND TECHNOLOGY LA English DT Article ID COUNTERFLOW DIFFUSION FLAMES; FIRE SUPPRESSANTS; EXTINCTION AB The suppression phenomena of a nonpremixed flame stabilized by a recirculation zone behind an obstruction in a combustion tunnel have been studied because of their relation to fires in aircraft engine nacelles, dry bays, and shipboard and ground-vehicle compartments. The JP-8 fuel was supplied as a liquid fuel pool, or a gaseous (methane or ethane) fuel issued from a flat porous plate. downstream of a backward-facing step or J-shape flange. The OH planar laser-induced fluorescence revealed a narrow. wrinkled diffusion flame zone that was deeply folded into the recirculation zone in response to the dynamic air entrainment and back-flow. Both transient and steady-state fire suppression limits were determined by impulsively injecting a gaseous fire-extinguishing agent (nitrogen, CF3Br, or C2HF5), or by continuously adding nitrogen, into the approaching airflow in the combustion tunnel. For high air velocities, the normalized critical agent mote fraction at suppression was a unique function of the agent injection period normalized by the effective mixing time in the recirculation zone, independent of types of fuels, agents, and obstacles. The extinction of the relatively low-strain-rate diffusion flame zone in the recirculation zone appears to determine the suppression limits of obstruction-stabilized flames. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Takahashi, F (reprint author), NASA, Natl Ctr Micrograv Res Fluids & Combust, Glenn Res Ctr, MS 500-115,21000 Brookpark Rd, Cleveland, OH 44135 USA. NR 34 TC 4 Z9 5 U1 0 U2 7 PU GORDON BREACH PUBLISHING, TAYLOR & FRANCIS GROUP PI PHILADELPHIA PA 325 CHESTNUT ST, 8TH FL, PHILADELPHIA, PA 19106 USA SN 0010-2202 J9 COMBUST SCI TECHNOL JI Combust. Sci. Technol. PY 2001 VL 163 BP 107 EP + DI 10.1080/00102200108952153 PG 27 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Energy & Fuels; Engineering GA 473TW UT WOS:000171065000005 ER PT J AU Herzinger, K AF Herzinger, K TI Ideals and duals generated by two elements in non-symmetric numerical semigroups SO COMMUNICATIONS IN ALGEBRA LA English DT Article ID TENSOR-PRODUCTS; RIGIDITY; INVERSE; TORSION; MODULES; TOR AB Let S be a numerical semigroup and let I be a relative ideal of S. Let S - I denote the dual of I and let mu (S)(.) represent the size of a minimal generating set. We investigate the inequality mu (S)(I)mu (S)(S - I) greater than or equal to mu (S)(I + (S - I)) under the assumptions that mu (I) = mu (S)(S - I) = 2 and S is non-symmetric. Specifically, we will identify some criterion involving the associated sets H(S) and S' which imply the strict inequality mu (S)(I)mu (S)(S - I) > mu (S)(I+(S-I)). C1 USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. RP Herzinger, K (reprint author), USAF Acad, Dept Math Sci, Colorado Springs, CO 80840 USA. NR 10 TC 2 Z9 2 U1 0 U2 0 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0092-7872 J9 COMMUN ALGEBRA JI Commun. Algebr. PY 2001 VL 29 IS 11 BP 5003 EP 5011 DI 10.1081/AGB-100106797 PG 9 WC Mathematics SC Mathematics GA 481XL UT WOS:000171545700010 ER PT J AU White, ED AF White, ED TI Investigating estimator consistency of nonlinear growth curve parameters SO COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION LA English DT Article DE infill asymptotics; maximum likelihood; spatial process AB Researchers often model biological growth data as a nonlinear function of time. This function involves unknown parameters that have intrinsic meaning to the researchers. Maximum likelihood provides a way to estimate these parameters. We present asymptotic results for the maximum likelihood estimators when adopting the generalized logistic function. Under increasing-domain asymptotics, the maximum likelihood estimators are consistent. Under infill asymptotics, evidence suggests they are not. C1 USAF, Inst Technol, Dept Math & Stat ENC, Wright Patterson AFB, OH 45433 USA. NR 7 TC 16 Z9 16 U1 0 U2 1 PU MARCEL DEKKER INC PI NEW YORK PA 270 MADISON AVE, NEW YORK, NY 10016 USA SN 0361-0918 J9 COMMUN STAT-SIMUL C JI Commun. Stat.-Simul. Comput. PY 2001 VL 30 IS 1 BP 1 EP 10 DI 10.1081/SAC-100001853 PG 10 WC Statistics & Probability SC Mathematics GA 455TQ UT WOS:000170044200002 ER PT S AU Lincoln, JW AF Lincoln, JW BE Grant, P Rousseau, CQ TI USAF experience in the qualification of composite structures SO COMPOSITE STRUCTURES: THEORY AND PRACTICE SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Composite Structures - Theory and Practice CY MAY 17-18, 1999 CL SEATTLE, WA SP ASTM Comm D 30 DE damage tolerance; moisture; temperature; impact damage; allowables; design development testing; full-scale testing; technology transition AB The prospect of significant reduction in aircraft structural mass has motivated the United States Air Force (USAF) and the aerospace industry to incorporate composite structures in their aircraft designs. The USAF found threats to structural integrity such as moisture, temperature, delaminations, and impact damage that made them take a cautious approach for the acquisition of aircraft with composite materials, Each of these threats acted as an inhibitor to using these materials in the design of operational aircraft. However, the USAF has successfully incorporated composites on several aircraft, including the B-2, C-17, and F-22. The challenge is to find new approaches for the qualification of composite structures that will make them more economically viable for future procurements. It is the purpose of this paper to discuss the background for the current qualification program for composites and suggest some possibilities for improvement of the certification process. C1 USAF, ASC EN, Wright Patterson AFB, OH 45433 USA. RP Lincoln, JW (reprint author), USAF, ASC EN, 2530 Loop Rd, Wright Patterson AFB, OH 45433 USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2862-2 J9 AM SOC TEST MATER PY 2001 VL 1383 BP 3 EP 11 DI 10.1520/STP14501S PG 9 WC Materials Science, Composites SC Materials Science GA BS14C UT WOS:000168820900001 ER PT J AU Birman, V Byrd, LW AF Birman, V Byrd, LW TI Matrix cracking in transverse layers of cross-ply beams subjected to bending and its effect on vibration frequencies SO COMPOSITES PART B-ENGINEERING LA English DT Article DE ceramic-matrix composites; vibration; matrix cracks ID COMPOSITE-MATERIAL; PLATES; DEFORMATION AB The solution for the matrix crack distribution in transverse layers of a cross-ply beam subjected to bending is developed based on the model of Han and Hahn (Compos Sci Technol 35 (1989) 377). This solution accounts for a bimodulus-type of the material response. As a result, it is possible to predict the extent and distribution of matrix cracks as well as the stiffness distribution in the beam subjected to bending, accounting for residual thermal stresses. The results of the solution of the bending problem are employed in the analysis of free and forced vibrations of a cross-ply beam with matrix cracks in transverse layers. The solution differs from the case of vibrations of an intact beam due to a difference in response of damaged layers under tension and compression. The results are shown for the natural frequency of a representative ceramic matrix composite (CMC) beam. (C) 2001 Elsevier Science Ltd. Ail rights reserved. C1 Univ Missouri, Engn Educ Ctr, St Louis, MO 63121 USA. USAF, Res Lab, VASM, Wright Patterson AFB, OH 45433 USA. RP Birman, V (reprint author), Univ Missouri, Engn Educ Ctr, 8001 Nat Bridge Rd, St Louis, MO 63121 USA. NR 19 TC 15 Z9 15 U1 3 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1359-8368 J9 COMPOS PART B-ENG JI Compos. Pt. B-Eng. PY 2001 VL 32 IS 1 BP 47 EP 55 DI 10.1016/S1359-8368(00)00035-4 PG 9 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA 397XK UT WOS:000166723600005 ER PT J AU Kwon, YW Liu, CT AF Kwon, YW Liu, CT TI Effect of particle distribution on initial cracks forming from notch tips of composites with hard particles embedded in a soft matrix SO COMPOSITES PART B-ENGINEERING LA English DT Article DE micro-mechanics; finite element analysis (FEA); particle distribution ID PARTICULATE COMPOSITES; FIBROUS COMPOSITES; DAMAGE EVOLUTION AB This paper studied the size of a so-called initial crack occurring at a notch tip caused by strain concentration in a particulate composite. The composite had hard and strong particles embedded in a soft and weak matrix material. Therefore, the crack formed in the matrix material but not in particles. This study discusses a computational model and a criterion to predict lengths of initial cracks. The predicted results agree well with average values obtained from the experiments. However, the experimental data showed scattering. Zn order to understand such scattered data, the effect of particle distribution on the initial crack size was studied numerically. The study showed that a variation in particle volume fraction did not affect the crack length as long as the specimen had a uniform particle distribution. However, a local variation of particle distribution in a specimen had a significant effect on the initial crack length confirming the scattered data. The size of the localized zone was about 2 mm or less which was the smallest size of the specimen to represent the smeared homogeneous properties of the composite material. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USN, Postgrad Sch, Dept Mech Engn, Monterey, CA 93943 USA. USAF, Res Lab, OL AC, Edwards AFB, CA 93524 USA. RP Kwon, YW (reprint author), USN, Postgrad Sch, Dept Mech Engn, 700 Dyer Rd, Monterey, CA 93943 USA. NR 15 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1359-8368 J9 COMPOS PART B-ENG JI Compos. Pt. B-Eng. PY 2001 VL 32 IS 3 SI SI BP 199 EP 208 DI 10.1016/S1359-8368(00)00056-1 PG 10 WC Engineering, Multidisciplinary; Materials Science, Composites SC Engineering; Materials Science GA 422HZ UT WOS:000168113600004 ER PT J AU Raghavan, P Moorthy, S Ghosh, S Pagano, NJ AF Raghavan, P Moorthy, S Ghosh, S Pagano, NJ TI Revisiting the composite laminate problem with an adaptive multi-level computational model SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article ID FINITE-ELEMENT METHOD AB The series of free-edge boundary-value problems treated by Pagano and Rybicki (Pagano NJ, Rybicki EF. On the significance of effective modulus solutions for fibrous composite. J Comp Mat 1974;8: 214-28; Rybicki EF, Pagano NJ. A study of the influence of microstructure on the modified effective modulus approach for composite laminates. Proceedings of the 1975 Int. Conf. Compos. Mater 1976;2:198-207) demonstrates the breakdown of homogenization in the region of macroscopic gradients. Their study shows the need for an appropriate level of resolution in determining reasonably accurate stresses in the region of macro gradients. Problems of this type can be readily handled by using an adaptive multi-level computational model with varying resolutions for critical and non-critical regions. The model introduces three levels, a pure macroscopic problem with homogenized coefficients modeled through a conventional displacement based FE code, macro-micro coupling through asymptotic homogenization where periodicity of microstructure is assumed, and microscopic analysis using a Voronoi cell finite-element model. The effect of increasing number of rows on the results is studied by the multiscale model and the homogenized model. Fiber/matrix interfacial stresses are also provided as these are expected to initiate the failure process in these fiber-reinforced composite laminates. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Ohio State Univ, Dept Mech Engn, Columbus, OH 43210 USA. AFRL, MLBC, Wright Patterson AFB, OH 45433 USA. RP Ghosh, S (reprint author), Ohio State Univ, Dept Mech Engn, 204 W 18th Ave, Columbus, OH 43210 USA. RI Ghosh, Somnath/A-2867-2012 NR 30 TC 39 Z9 40 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0266-3538 J9 COMPOS SCI TECHNOL JI Compos. Sci. Technol. PY 2001 VL 61 IS 8 BP 1017 EP 1040 DI 10.1016/S0266-3538(00)00230-X PG 24 WC Materials Science, Composites SC Materials Science GA 452BP UT WOS:000169837500003 ER PT J AU Kramb, VA John, R Stubbs, DA AF Kramb, VA John, R Stubbs, DA TI A study of the damage progression from notches in an oxide/oxide ceramic-matrix composite using ultrasonic C-scans SO COMPOSITES SCIENCE AND TECHNOLOGY LA English DT Article DE ceramic composites; damage progression; non-destructive evaluation; notched fracture; oxide/oxide; ultrasound AB The damage progression from notches during quasi-monotonic loading was investigated in an oxide/oxide ceramic-matrix composite using ultrasonic C-scans. Test specimens were monotonically loaded, removed from the test machine, then ultrasonically C-scanned using a through transmission, reflector plate method. The level of ultrasonic attenuation was monitored as a function of applied stress and correlated with the damage observed within the composite. Results of the study showed that the ultrasonic technique successfully monitored the progressive matrix cracking prior to the peak load in specimens tested at 23 degreesC. Close to the peak load, fiber breakage occurred near the notch tip, which was not indicated by the ultrasonic C-scans, At 950 degreesC, damage progressed from the notch as a single dominant crack. The extent of enhanced ultrasonic attenuation in the C-scans correlated well with the crack length from the notch. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Dayton, Res Inst, Dayton, OH 45469 USA. USAF, Res Lab, MLLN, AFRLL,Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Kramb, VA (reprint author), Univ Dayton, Res Inst, 300 Coll Pk, Dayton, OH 45469 USA. NR 13 TC 9 Z9 9 U1 0 U2 7 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0266-3538 J9 COMPOS SCI TECHNOL JI Compos. Sci. Technol. PY 2001 VL 61 IS 11 BP 1561 EP 1570 DI 10.1016/S0266-3538(01)00051-3 PG 10 WC Materials Science, Composites SC Materials Science GA 464NV UT WOS:000170539400007 ER PT J AU Farmer, B Pachter, R Patnaik, S Rigby, D Tashiro, K AF Farmer, B Pachter, R Patnaik, S Rigby, D Tashiro, K TI Special issue - Multiscale modeling of organic materials SO COMPUTATIONAL AND THEORETICAL POLYMER SCIENCE LA English DT Editorial Material C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. Osaka Univ, Suita, Osaka 565, Japan. RP Pachter, R (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1089-3156 J9 COMPUT THEOR POLYM S JI Comput. Theor. Polym. Sci. PY 2001 VL 11 IS 5 BP 327 EP 327 DI 10.1016/S1089-3156(01)00020-4 PG 1 WC Polymer Science SC Polymer Science GA 466ZU UT WOS:000170676700001 ER PT J AU Wang, ZQ Lupo, JA Patnaik, S Pachter, R AF Wang, ZQ Lupo, JA Patnaik, S Pachter, R TI Large scale molecular dynamics simulations of a 4-n-pentyl-4 '-cyanobiphenyl (5CB) liquid crystalline model in the bulk and as a droplet SO COMPUTATIONAL AND THEORETICAL POLYMER SCIENCE LA English DT Article; Proceedings Paper CT Spring Meeting of the MRS CY 2000 CL SAN FRANCISCO, CALIFORNIA SP MRS DE large scale molecular dynamics; 5CB; liquid crystal droplet; orientational order; fast multipole method; CHARMM ID FAST MULTIPOLE METHOD; COMPUTER-SIMULATIONS; ALGORITHM; PHASE; ORDER AB Molecular dynamics simulations for 4-n-pentyl-4'-cyanobiphenyl (5CB) with as many as 944 molecules are reported. The order-N fast multipole method (FMM) is used to treat the long-range interactions. For a droplet of 944 molecules, the simulation shows a correlation between the droplet shape and the nematic order and a strong surface effect; little nematic order is found in a 118 molecule droplet. Simulations of the bulk system result in similar order parameters for both the 118 and 944 molecular ensembles. Although the nematic-isotropic transition was not observed at temperatures as high as 400 K using the CHARMM force field, a modification of the force field using ab initio determined partial atomic charges lowers the order parameters. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Pachter, R (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 22 TC 23 Z9 23 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 1089-3156 J9 COMPUT THEOR POLYM S JI Comput. Theor. Polym. Sci. PY 2001 VL 11 IS 5 BP 375 EP 387 DI 10.1016/S1089-3156(01)00017-4 PG 13 WC Polymer Science SC Polymer Science GA 466ZU UT WOS:000170676700005 ER PT S AU Brungart, DS AF Brungart, DS BE Greenberg, S Slaney, M TI Preliminary model of auditory distance perception for nearby sources SO COMPUTATIONAL MODELS OF AUDITORY FUNCTION SE NATO SCIENCE SERIES, SERIES A: LIFE SCIENCE LA English DT Proceedings Paper CT Conference of the NATO Advanced-Study-Institute on Computational Hearing CY JUL 01-12, 1998 CL IL CIOCCO, ITALY SP NATO, USN, Off Res, USAF, Off Sci Res C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Brungart, DS (reprint author), USAF, Res Lab, Human Effectiveness Directorate, 2610 7th St, Wright Patterson AFB, OH 45433 USA. NR 16 TC 4 Z9 4 U1 0 U2 0 PU I O S PRESS PI AMSTERDAM PA NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS SN 1387-6686 BN 90-5199-457-5 J9 NATO SCI S A LIF SCI PY 2001 VL 312 BP 83 EP 95 PG 13 WC Acoustics; Computer Science, Interdisciplinary Applications; Neurosciences; Otorhinolaryngology SC Acoustics; Computer Science; Neurosciences & Neurology; Otorhinolaryngology GA BT88W UT WOS:000174363200010 ER PT J AU Onen, BH Dietz, DC Yen, VC Moore, AH AF Onen, BH Dietz, DC Yen, VC Moore, AH TI Goodness-of-fit tests for the Cauchy distribution SO COMPUTATIONAL STATISTICS LA English DT Article DE Cauchy distribution; goodness-of-fit; Monte Carlo; Kolmogorov-Smirnov test; Kuiper test AB This article presents several modified goodness-of-fit tests for the Cauchy distribution with unknown location and scale parameters. Monte Carlo studies are performed to calculate critical values for several tests based on the empirical distribution function. Power studies suggest that the modified Kuiper (V) test is the most powerful standard test against most alternate distributions over a full range of sample sizes. A reflection technique is also employed which yields substantial improvement in the power of this test against symmetric distributions. C1 USAF, Inst Technol, AFIT EN, Wright Patterson AFB, OH 45433 USA. RP Onen, BH (reprint author), USAF, Inst Technol, AFIT EN, 2650 P St,Bldg 640, Wright Patterson AFB, OH 45433 USA. NR 19 TC 0 Z9 0 U1 0 U2 1 PU PHYSICA-VERLAG GMBH & CO PI HEIDELBERG PA TIERGARTENSTRASSE 17, 69121 HEIDELBERG, GERMANY SN 0943-4062 J9 COMPUTATION STAT JI Comput. Stat. PY 2001 VL 16 IS 1 BP 97 EP 107 DI 10.1007/s001800100053 PG 11 WC Statistics & Probability SC Mathematics GA 428WG UT WOS:000168484200005 ER PT J AU Chilton, L Suri, M AF Chilton, L Suri, M TI Locking-free mixed hp finite element methods for curvilinear domains SO COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING LA English DT Article DE p version; hp version; spectral elements; curved elements; finite elements; mixed methods; locking; geometrically nonlinear elasticity ID ELASTICITY PROBLEMS; STOKES-FLOW; APPROXIMATION AB Mixed hp finite element methods (FEMs) are robust with respect to Poisson ratio locking when straight-sided quadrilateral elements are used. For the p version, which uses Fixed and generally large elements. curved elements are necessary to represent curved domains accurately. We show that mixed hp curved quadrilateral elements retain the robustness of their straight-sided counterparts, provided degenerate elements are avoided. We also show that lip version triangles are robust. We use these concepts to develop a locking-Free FEM for geometrically-nonlinear elasticity. (C) 2001 Elsevier Science B.V. All rights reserved. C1 USAF, Inst Technol, Dept Math & Stat, Wright Patterson AFB, OH 45433 USA. Univ Maryland, Dept Math & Stat, Baltimore, MD 21250 USA. RP Chilton, L (reprint author), USAF, Inst Technol, Dept Math & Stat, AFIT-ENC Bldg 640,2950 P St, Wright Patterson AFB, OH 45433 USA. EM lchilton@afit.af.mil; suri@math.umbc.edu NR 17 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0045-7825 J9 COMPUT METHOD APPL M JI Comput. Meth. Appl. Mech. Eng. PY 2001 VL 190 IS 26-27 BP 3427 EP 3442 DI 10.1016/S0045-7825(00)00277-2 PG 16 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA 420BQ UT WOS:000167984400006 ER PT J AU Harris, LD Custer, LB Soranaka, ET Burge, JR Ruble, GR AF Harris, LD Custer, LB Soranaka, ET Burge, JR Ruble, GR TI Evaluation of objects and food for environmental enrichment of NZW rabbits SO CONTEMPORARY TOPICS IN LABORATORY ANIMAL SCIENCE LA English DT Article AB The Guide for the Care and Use of Laboratory Animals states that both structural and social environments should be considered when addressing the husbandry needs of laboratory animals. The purpose of this study was to investigate environmental enrichment strategies that could potentially enhance the well-being of rabbits. Male and female 6-week old New Zealand White rabbits were divided into three groups: food-enriched (Bunny Stix, Bunny Blocks, or celery), non-food enriched (Jingle Ball, Kong toy, or Nylabone), and not enriched. Animals were given a particular enrichment for 1 h daily for 15 days. Home cages were fitted with specially designed plexiglass doors, which allowed the animals' interactions with the objects to be videotaped. The amount of time the animal interacted with each object and the total activity during the I-h taped session were recorded for each rabbit. Rabbits were weighed weekly. Rabbits spent significantly more time interacting with the Bunny Stir than any other food item or non-food object. In addition, total activity time was significantly greater for all rabbits enriched with food versus any of the non-food items. Weight gains after 15 days did not differ significantly, but there was a trend towards increased weight gains in food-enriched rabbits. In this study, food was a stronger, more sustained enrichment device than were non-food objects. C1 Walter Reed Army Inst Res, Div Vet Med, Silver Spring, MD 20910 USA. RP Harris, LD (reprint author), 1219 Knight St, Lackland AFB, TX 78236 USA. NR 10 TC 12 Z9 12 U1 1 U2 6 PU AMER ASSOC LABORATORY ANIMAL SCIENCE PI MEMPHIS PA 9190 CRESTWYN HILLS DR, MEMPHIS, TN 38125 USA SN 1060-0558 J9 CONTEMP TOP LAB ANIM JI Contemp. Top. Lab. Anim. Sci. PD JAN PY 2001 VL 40 IS 1 BP 27 EP 30 PG 4 WC Veterinary Sciences; Zoology SC Veterinary Sciences; Zoology GA 397MV UT WOS:000166700200005 PM 11300672 ER PT B AU Davis, T Tomlinson, BJ Ledbetter, J AF Davis, T Tomlinson, BJ Ledbetter, J BE Ross, RG TI Military space cryogenic cooling requirements for the 21st century SO CRYOCOOLERS 11 LA English DT Proceedings Paper CT 11th International Cryocooler Conference CY JUN 20-22, 2000 CL BALL AEROSP & TECHNOLOGIES CORP, KEYSTONE, CO HO BALL AEROSP & TECHNOLOGIES CORP AB Current space cryocooler developments have achieved performance and capability that have made the use of active refrigeration in space missions feasible. Space flight demonstrations such as the Sandia National Laboratory Cobra Brass and Multispectral Thermal Imager missions, the National Aeronautics and Space Administration SABER, Hyperion, and AIRS missions baselined and implemented active refrigeration to achieve mission goals. The NASA retrofit of the NICMOS cooling system on the Hubble Space Telescope, due to be installed during a 2001 servicing mission, will use a reverse Brayton cycle cryocooler to provide cooling for the NICMOS sensor due to a prematurely depleted cryogen dewar. These applications of cryocooler technology validate the improved mission capabilities and reliability and lifetime confidence in active refrigeration in space. Past development efforts have focused primarily on reliability and the achievement of long life. However, looking ahead at 21st century military space applications, there are improvements needed in several aspects of current cooling technology including higher capacity cooling loads, mass reduction, and improvement in efficiency, low temperature performance, and lifetimes greater than 10 years. In addition, cryogenic integration technology must be developed to allow efficient cryocooler to cooled component integration. Significant improvements in cryocooler technology can easily be overshadowed by gross parasitic heat loads and unacceptable cryogenic system penalties. This paper focuses on mid-term and out-year cooling requirements for the Air Force Space Based Infrared System Low, Space Based Laser, Advanced Space Based Infrared System, and other Department of Defense space missions. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Davis, T (reprint author), USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. NR 6 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 0-306-46567-1 PY 2001 BP 1 EP 9 PG 9 WC Engineering, Aerospace; Thermodynamics; Engineering, Mechanical; Physics, Applied SC Engineering; Thermodynamics; Physics GA BT66F UT WOS:000173666500001 ER PT B AU Tomlinson, BJ Yoneshige, CH Abhyankar, NS AF Tomlinson, BJ Yoneshige, CH Abhyankar, NS BE Ross, RG TI Air Force Research Laboratory cryocooler characterization and endurance update SO CRYOCOOLERS 11 LA English DT Proceedings Paper CT 11th International Cryocooler Conference CY JUN 20-22, 2000 CL BALL AEROSP & TECHNOLOGIES CORP, KEYSTONE, CO HO BALL AEROSP & TECHNOLOGIES CORP AB The Air Force Research Laboratory (AFRL) has been instrumental in advancing space cryocooler technology through cryocooler development and characterization of the. long-term performance of different types of cryocoolers. These coolers were developed to support the long life space mission requirements of the United States Air Force SBIRS-Low Program Office, the Ballistic Missile Defense Organization (BMDO), the National Aeronautics and Space Administration and the Department of Defense. Long life cryocooler applications include cooling infrared sensors, focal planes, optics and electronic circuits for various space missions of national interest. The main objective of this paper is to present the status of the cryocoolers currently undergoing characterization and endurance evaluation at AFRL. The information gained through these processes is shared with industry partners, cryocooler developers, technology sponsors, and technology users. This feedback is essential for cryocooler design enhancements and future cryogenic technology development efforts. There are two cryocoolers undergoing characterization at AFRL. These include the Astrium (formerly Matra Marconi Space) 10 K Cryocooler, and the TRW 150 K miniature pulse tube (150K MPT). In addition, there are five cryocoolers undergoing endurance evaluation at AFRL These include the Raytheon Protoflight Spacecraft Cryocooler, Raytheon Standard Spacecratt Cryocooler (SSC) II, TRW 3585, TRW 6020, and the Defense Evaluation and Research Agency (DERA) cryocooler. This paper includes each cryocooler's status, and update or initial report on its performance, elapsed run-time hours, performance anomalies and updated characterization and endurance evaluation data. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Tomlinson, BJ (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 1 U2 2 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46567-1 PY 2001 BP 17 EP 25 PG 9 WC Engineering, Aerospace; Thermodynamics; Engineering, Mechanical; Physics, Applied SC Engineering; Thermodynamics; Physics GA BT66F UT WOS:000173666500003 ER PT B AU Abhyankar, NS Yoneshige, CH Tomlinson, BJ Reilly, J AF Abhyankar, NS Yoneshige, CH Tomlinson, BJ Reilly, J BE Ross, RG TI Characterization of Raytheon's 60 K 2W Protoflight Spacecraft Cryocooler SO CRYOCOOLERS 11 LA English DT Proceedings Paper CT 11th International Cryocooler Conference CY JUN 20-22, 2000 CL BALL AEROSP & TECHNOLOGIES CORP, KEYSTONE, CO HO BALL AEROSP & TECHNOLOGIES CORP AB The Air Force Research Laboratory Cryogenic Cooling Research Facility is supported by the Ballistic Missile Defense Organization (BMDO) and the U.S. Air Force SBIRS Low Program Office. It was created to characterize the thermodynamic performance and long life potential of cryogenic cooling technologies developed by various defense industry contractors. The objectives of the characterization process are to explore the cooler's ability to perform at its design point and to map its range of thermodynamic operation. This provides a detailed performance envelope for alternative space applications and aids in providing valuable feedback to cryocooler developers. This paper provides an overview of the AFRL characterization of the Protoflight Spacecraft Cryocooler (PSC) built by Raytheon Systems Co. The PSC is a split Stirling cryocooler with dual, opposing motion compressors and a displacer, which uses a mass balancer to reduce vibration. It is designed to lift a beat load of 2W at 60K, with a nominal rejection temperature of 300K. The characterization of the PSC involved a series of experiments, including cool-down to lowest temperature, design point verification, parameter optimization, stiction tests, long term-stability, transient thermal response (due to orbital temperature variation) and a proto-qualification thermal vacuum test. The performance map is charted providing a graphical display of important parameters including specific power, calculated as input power per watt of cooling. The off-nominal performance evaluation included lifting 1.2W at 35K and 6W at 120K, while operating within recommended total input power and stroke boundaries. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Abhyankar, NS (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 USA. NR 0 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 0-306-46567-1 PY 2001 BP 45 EP 53 PG 9 WC Engineering, Aerospace; Thermodynamics; Engineering, Mechanical; Physics, Applied SC Engineering; Thermodynamics; Physics GA BT66F UT WOS:000173666500006 ER PT B AU Tomlinson, BJ Yoneshige, CH Martin, ML AF Tomlinson, BJ Yoneshige, CH Martin, ML BE Ross, RG TI Initial observations from the disassembly and inspection of the TRW 3503 and Creare SSRB SO CRYOCOOLERS 11 LA English DT Proceedings Paper CT 11th International Cryocooler Conference CY JUN 20-22, 2000 CL BALL AEROSP & TECHNOLOGIES CORP, KEYSTONE, CO HO BALL AEROSP & TECHNOLOGIES CORP AB The importance of long term endurance evaluation data on cryocooler technology cannot be overemphasized. As useful and important as operational data is failure analysis data and the lessons learned from those failures, During fiscal year 1999, the TRW 3503 pulse tube and the Creare Single Stage Reverse Brayton (SSRB) stopped operating during endurance evaluation at the Air Force Research Laboratory (AFRL) Cryogenic Cooling Research Facility (CCRF). On 8-9 November 1998, the TRW 3503 pulse tube cryocooler suffered a system overheat as a result of an environmental control electronics failure. The cooler kept operating throughout the overheat and continued to run after the enviromental system was stabilized. The TRW 3503 continued to run with only a small performance degradation of approximately +2K over the design point with a heat load of 0.3W until it tripped and shut down on 20 April 1999. The cooler would not restart, so AFRL engineers and technicians worked with TRW to investigate the cause of the tripping. On 19 December 1998, the Creare SSRB shut down due to an enviromental system fail-safe overheat condition on the compressor. Subsequent attempts to restart the cooler were unsuccessful, The compressor started normally, but the free spinning turboexpander (TE) was not able to lift off of its bearings and start spinning. AFRL personnel worked with Creare to investigate the cause of the TE's inability to lift up and spin. This paper will discuss the investigation of both cryocoolers' inability to restart, initial observations in post-endurance disassembly, and lessons learned from these experiences. C1 USAF, Kirtland AFB, NM 87117 USA. RP Tomlinson, BJ (reprint author), USAF, Kirtland AFB, NM 87117 USA. NR 3 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 0-306-46567-1 PY 2001 BP 673 EP 679 PG 7 WC Engineering, Aerospace; Thermodynamics; Engineering, Mechanical; Physics, Applied SC Engineering; Thermodynamics; Physics GA BT66F UT WOS:000173666500083 ER PT B AU Yoneshige, CH Abhyankar, NS Kallman, JP Lybarger, GW Martin, ML AF Yoneshige, CH Abhyankar, NS Kallman, JP Lybarger, GW Martin, ML BE Ross, RG TI A fail-safe experiment stand for cryocooler characterization SO CRYOCOOLERS 11 LA English DT Proceedings Paper CT 11th International Cryocooler Conference CY JUN 20-22, 2000 CL BALL AEROSP & TECHNOLOGIES CORP, KEYSTONE, CO HO BALL AEROSP & TECHNOLOGIES CORP AB Understanding possible failure mechanisms is the first step in the prevention and impact minimization of experiment stand failures in any research facility. As the facility encompasses a wider range of multiplicity of experiments, these mechanisms can become coupled, requiring careful planning and preventative measures. This paper will discuss the possible experiment stand failure modes and safeguards used to minimize the impact that experiment stand failures have on the cryocooler characterization process at the Cryogenic Cooling Research Facility at the Air Force Research Laboratory (AFRL). The facility is equipped with one 6 foot, two 18 inch, two 36 inch and eight 24 inch thermal vacuum chambers along with all of the equipment, specialized tools and instruments required for the short term performance characterization and long term endurance evaluation of cryogenic coolers. The laboratory characterizes cryocoolers based on various thermodynamic cycles, such as the Stirling cycle, pulse tube (Stirling cycle variant) and reverse Brayton cycle, at various levels of technical maturity. These cryocoolers were developed to satisfy space mission requirements from the United States Air Force (SBIRS-Low Program Office), The Ballistic Missile Defense Organization (BMDO), the National Aeronautics and Space Administration (NASA) and the Department of Defense. The prevention of experiment stand failures related to cryocooler characterization will be discussed from different standpoints, including the vacuum system, equipment interfaces, electronics, software programs, communication systems, and electronic remote notification systems. C1 USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. RP Yoneshige, CH (reprint author), USAF, Res Lab, Space Vehicles Directorate, Kirtland AFB, NM 87117 USA. NR 0 TC 0 Z9 0 U1 1 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA BN 0-306-46567-1 PY 2001 BP 699 EP 705 PG 7 WC Engineering, Aerospace; Thermodynamics; Engineering, Mechanical; Physics, Applied SC Engineering; Thermodynamics; Physics GA BT66F UT WOS:000173666500086 ER PT B AU Tomlinson, BJ Davis, TM Ledbetter, JD AF Tomlinson, BJ Davis, TM Ledbetter, JD BE Ross, RG TI Advanced cryogenic integration and cooling technology for space-based long term cryogen storage SO CRYOCOOLERS 11 LA English DT Proceedings Paper CT 11th International Cryocooler Conference CY JUN 20-22, 2000 CL BALL AEROSP & TECHNOLOGIES CORP, KEYSTONE, CO HO BALL AEROSP & TECHNOLOGIES CORP AB The Air Force Research Laboratory (AFRL), Space Vehicles Directorate has been the lead Department of Defense (DoD) agency for the development of low capacity cryogenic refrigerators and integration technologies for space applications since the late 1980s. High capacity cryocoolers and long term (>20 years) on orbit propellant storage are potentially enabling technology for future High Energy Laser (HEL) space systems, orbital transfer vehicles, and on orbit propellant depots. Cryogenic applications in space based systems requiring long term cryogen storage includes: significant cooling requirements for subcritical cryogens, cryocooler redundancy issues, on orbit cryogen transfer from vehicle to vehicle, large shield cooling, long term gas and liquid cryogen storage, large distributed cooling surfaces, cryogenic system integration issues, and significant spacecraft system penalties due to mass and input power. AFRL has pursued low capacity cryocooler concepts including reverse Brayton cycle, single and multiple stage Stirling cycle, advanced Joule-Thomson cycle, and Pulse Tube (Stirling cycle variant) designs. The cryocooler technology spans a wide range of cooling temperatures (from similar to10 Kelvin to 150 Kelvin) and heat loads (up to 10 Watts at 95 Kelvin). Additionally, AFRL has pursued advanced cryogenic integration technology including cryogenic thermal switches, cryogenic heat transport, thermal storage, and cryogenic integration schemes to reduce system mass and input power penalties. Current cryogenic integration and cryocooler development programs address the negative impacts of the cryogenic system on optical space systems including: induced line of sight vibration, longevity, power consumption, mass, thermal transport, thermal storage, and thermal switching. However, the cryogenic cooling requirements for future Air Force systems may require large capacity cryogenic cooling, extremely mass and power efficient mechanical refrigerators, and significant improvements in long term on orbit cryogen storage. The technical efforts at AFRL concentrate on exploratory and advanced development programs that focus on the development of technology from concept and breadboard engineering models to protoflight models that are geared to experimental characterization and technology transition for flight demonstrations and, potentially, operational programs. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP Tomlinson, BJ (reprint author), USAF, Res Lab, 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 0-306-46567-1 PY 2001 BP 749 EP 758 PG 10 WC Engineering, Aerospace; Thermodynamics; Engineering, Mechanical; Physics, Applied SC Engineering; Thermodynamics; Physics GA BT66F UT WOS:000173666500091 ER PT J AU Elston, DM AF Elston, DM TI Dermatology: 2001 SO CUTIS LA English DT Editorial Material C1 Brooke Army Med Ctr, Dept Dermatol MCHEDD, Ft Sam Houston, TX 78234 USA. Wilford Hall USAF Med Ctr, San Antonio, TX 78236 USA. RP Elston, DM (reprint author), Brooke Army Med Ctr, Dept Dermatol MCHEDD, 3851 Roger Brooke Dr, Ft Sam Houston, TX 78234 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU EXCERPTA MEDICA INC PI NEW YORK PA 650 AVENUE OF THE AMERICAS, NEW YORK, NY 10011 USA SN 0011-4162 J9 CUTIS JI Cutis PD JAN PY 2001 VL 67 IS 1 BP 18 EP 18 PG 1 WC Dermatology SC Dermatology GA 391PN UT WOS:000166364500001 PM 11204596 ER PT J AU Berend, SA Hale, DW Engstrom, MD Greenbaum, IF AF Berend, SA Hale, DW Engstrom, MD Greenbaum, IF TI Cytogenetics of collared lemmings (Dicrostonyxgroenlandicus). II. Meiotic behavior of B chromosomes suggests a Y-chromosome origin of supernumerary chromosomes SO CYTOGENETICS AND CELL GENETICS LA English DT Article ID SYNAPTONEMAL COMPLEX-ANALYSIS; SEX-CHROMOSOMES; X-CHROMOSOME; ROBERTSONIAN TRANSLOCATION; DNA-SEQUENCES; PROPHASE-I; DEER MOUSE; MALE-MICE; HETEROCHROMATIN; SPERMATOCYTES AB The patterns of synapsis and chiasma formation of the B chromosomes of male collared lemmings (Dicrostonyx groenlandicus) were analyzed by light and electron microscopy and compared to expectations for various hypotheses for the intragenomic origin of supernumerary chromosomes. Pachytene analysis revealed a variety of synaptic configurations including B-chromosome univalents, bivalents and trivalents. In approximately one-half of the pachytene nuclei examined, B chromosomes were in synaptic associations with the normally unpaired portion of the Y chromosome. The B-chromosome configurations at pachynema, including those involving the Y chromosome, were maintained into diakinesis and metaphase I. The meiotic behavior of the B chromosomes was inconsistent with their derivation from centric-fusion products, isochromosome formation, small-autosome polysomy, or the X chromosome. However, the frequent synapsis and apparent recombination between B chromosomes and the Y chromosome implicate this sex chromosome as a possible source of the B chromosomes in collared lemmings. Copyright (C) 2002 S. Karger AG, Basel. C1 Texas A&M Univ, Dept Biol, College Stn, TX 77843 USA. USAF Acad, Dept Biol, Colorado Springs, CO 80840 USA. Royal Ontario Museum, Ctr Biodivers & Conservat Biol, Toronto, ON M5S 2C6, Canada. RP Greenbaum, IF (reprint author), Texas A&M Univ, Dept Biol, College Stn, TX 77843 USA. FU NIGMS NIH HHS [GM 27014] NR 50 TC 7 Z9 7 U1 0 U2 1 PU KARGER PI BASEL PA ALLSCHWILERSTRASSE 10, CH-4009 BASEL, SWITZERLAND SN 0301-0171 J9 CYTOGENET CELL GENET JI Cytogenet. Cell Genet. PY 2001 VL 95 IS 1-2 BP 85 EP 91 DI 10.1159/000057023 PG 7 WC Cell Biology; Genetics & Heredity SC Cell Biology; Genetics & Heredity GA 549AJ UT WOS:000175422100016 PM 11978976 ER PT J AU Lai, D AF Lai, D TI The great power dilemma: The trade-off between defense and growth in Great Britain, 1830-1980 SO DEFENCE AND PEACE ECONOMICS LA English DT Article DE military spending; economic growth; externality effects ID TIME-SERIES DATA; ECONOMIC-GROWTH; GOVERNMENT SIZE; PEACE DIVIDEND; UNITED-STATES; CROSS-SECTION; EXPENDITURES; FRAMEWORK AB This study investigates the relationship between British economic performance and various macroeconomic factors during the rise and fall of Great Britain as a great power from 1830 to 1980. It has generated a number of interesting findings. First, Britain's military spending is found to have a direct yet negative impact on its economic output. Second, this negative effect appears to be moderate as compared to the stronger positive effect of investment. Third, the results reveal that the effects of various factors on Britain's economy underwent a structural change during this long period of time. The most notable one is military spending. It suggests that in the nineteenth century when Britain was on the rise and strong, its military spending did not appear to hinder its economic performance. However, the trade-off effects emerged in the twentieth century to hurt Britain's economy, contributing to Britain's relative decline in the post-war era. C1 US Air War Coll, Dept Int Secur Studies, Maxwell AFB, AL 36112 USA. RP Lai, D (reprint author), US Air War Coll, Dept Int Secur Studies, Maxwell AFB, AL 36112 USA. NR 44 TC 0 Z9 0 U1 2 U2 2 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 1024-2694 J9 DEFENCE PEACE ECON JI Def. Peace Econ. PY 2001 VL 12 IS 2 BP 145 EP 156 DI 10.1080/10430710108404981 PG 12 WC Economics SC Business & Economics GA 641XE UT WOS:000180771700003 ER PT S AU Latham, WP Roychoudhuri, CS Bullington, J AF Latham, WP Roychoudhuri, CS Bullington, J BE Osinski, M Chua, SJ Ishibashi, A TI High-power grating-coupled surface-emitting diode lasers SO DESIGN, FABRICATION, AND CHARACTERIZATION OF PHOTONIC DEVICES II SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Design, Fabrication, and Characterization of Photonic Devices II CY NOV 27-30, 2001 CL SINGAPORE, SINGAPORE SP SPIE, Nanyang Technol Univ AB Both government and industry have a long-standing interest in developing low-cost high-power semiconductor lasers for a variety of applications. These include material processing, long range sensing, and long-range communications. Key development goals are high brightness and high efficiency. This paper will review some of the applications, key laser performance features desired, and some of the past accomplishments in high power diode lasers from the High Power Semiconductor Laser Technology (HPSLT) program. One of the primary outgrowths of HPSLT was the Grating Coupled Surface Emitting Laser (GCSEL). GCSEL progress will be highlighted. C1 USAF, Res Lab, Directed Energy Directorate, Kirtland AFB, NM 87117 USA. RP Latham, WP (reprint author), USAF, Res Lab, Directed Energy Directorate, 3550 Aberdeen SE, Kirtland AFB, NM 87117 USA. NR 6 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4324-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4594 BP 86 EP 95 AR UNSP 4594-14 DI 10.1117/12.446533 PG 10 WC Engineering, Electrical & Electronic; Instruments & Instrumentation; Optics SC Engineering; Instruments & Instrumentation; Optics GA BU07G UT WOS:000174901400010 ER PT B AU Heidger, SL Baraty, NJ Weimer, JA AF Heidger, SL Baraty, NJ Weimer, JA BE Swain, GM Davidson, JL Angus, JC Ando, T Brown, WD TI CVD diamond for high power and high temperature electronics SO DIAMOND MATERIALS VII, PROCEEDINGS SE ELECTROCHEMICAL SOCIETY SERIES LA English DT Proceedings Paper CT 7th International Symposium on Diamond Materials CY SEP 07, 2002 CL SAN FRANCISCO, CA SP Electrochem Soc, Dielect Sci & Technol Div, Electrochem Soc, High Temp Mat Div, Electrochem Soc, Electr Div ID FILMS AB Polycrystalline diamond films produced by Microwave Plasma Enhanced Chemical Vapor Deposition (MWCVD) were investigated for use as dielectric materials for high power and high temperature passive devices. Film thicknesses ranged from 0.5 to I 00 mum and diamond grain sizes were < 1 to 30 mum depending on thickness. Capacitance and dielectric loss of metal-diamond-metal capacitors were measured as a function of frequency to. 10(6)Hz, and as a function of temperature from 25degreesC to 250degreesC. Breakdown strength, resistivity and I-V characteristics were also measured. CVD diamond films that were heat treated to 325degreesC for 2hrs., having Si + W + Au contacts, had very steady dielectric constants, ranging from 5 to 6.5, and very low losses, less than 0.005, over 100 to 10(6)HZ at room temperature. Dielectric constants of CVD diamond varied by less than 3% with temperature cycling to 250degreesC. Losses remained very low (less than 0.01) and stable up to 200degreesC. By 250degreesC, the dielectric loss had increased to nearly 8X (0.023) its room temperature value (0.003). The effective breakdown strengths of CVD diamond ranged from 2 to 10MV/cm and resistivities ranged from 10(13) to 10(15) Omega-cm. C1 USAF, AFRL, PRPE, Wright Patterson AFB, OH 45433 USA. RP Heidger, SL (reprint author), USAF, AFRL, PRPE, Wright Patterson AFB, OH 45433 USA. NR 10 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 1-56677-358-X J9 ELEC SOC S PY 2001 VL 2002 IS 25 BP 234 EP 239 PG 6 WC Electrochemistry; Engineering, Electrical & Electronic; Materials Science, Characterization & Testing; Physics, Condensed Matter SC Electrochemistry; Engineering; Materials Science; Physics GA BW04Q UT WOS:000180722400024 ER PT S AU Harris, S AF Harris, S BE Sutherland, RL Prather, DW Cindrich, I TI Characterization and application of a liquid crystal beam steering device SO DIFFRACTIVE AND HOLOGRAPHIC TECHNOLOGIES FOR INTEGRATED PHOTONIC SYSTEMS SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Diffractive and Holographic Technologies for Integrated Photonic Systems CY JAN 22-23, 2001 CL SAN JOSE, CA SP SPIE DE beam steering; liquid crystal; optical phased array; phase grating ID DISPERSION AB Optical Phased Array technology promises to reduce the size, weight, and power consumption of optical pointing and steering systems by replacing complex mechanically gimballed mirrors with small, lightweight, nonmechanical devices. This paper develops and describes several diagnostic techniques that can be used to evaluate the performance of Optical Phased Arrays (OPAs) and demonstrates their use by applying them to the evaluation of a commercially available liquid crystal device. Finally, the operation of this device is demonstrated by integrating it into a steered imaging system. C1 USAF, Res Lab, Multi Funct Elect Opt Branch, Sensors Directorate, Wright Patterson AFB, OH 45433 USA. RP Harris, S (reprint author), USAF, Res Lab, Multi Funct Elect Opt Branch, Sensors Directorate, 3109 P St, Wright Patterson AFB, OH 45433 USA. NR 6 TC 19 Z9 19 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 0-8194-3969-X J9 P SOC PHOTO-OPT INS PY 2001 VL 4291 BP 109 EP 119 DI 10.1117/12.424844 PG 11 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA BS31U UT WOS:000169433800014 ER PT S AU Foshee, J Tahim, RS Chang, K AF Foshee, J Tahim, RS Chang, K BE Rao, RM Dianat, SA Zoltowski, MD TI Multi-band phased array antennas for wireless communications SO DIGITAL WIRELESS COMMUNICATION III SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Digital Wireless Communication III CY APR 17-18, 2001 CL ORLANDO, FL SP SPIE DE phased array antenna; multi-band transmitter; low noise amplifier; diplexer; low loss phase shifter; multi-band radiating elements; microwave integrated circuits; MMIC-chips; electronic beam steering; piezoelectric transducers ID SHIFTERS AB Need for exchanging a wide range of information among many users in a timely manner, has resulted in a rapid expansion of frequency utilization, in addition to bandwidth expansion. High resolution video, infrared sensors, and various types of radars now are expected to be readily exchanged among users, and these users can be located on the surface, in the air and these users can be expected to be not only mobile, but highly mobile. To exchange this high volume information reliably among these many users requires a high data rate and the use of directional antennas. The use of directional antennas would also tend to reduce the possibility of interference among the users and also reduce the RF terminal power consumption requirements. This paper describes a multi-functional phased array antenna design, which can operate at either Ku-Band or Ka-Band without the need for switching or reconfiguration; and can be readily switched to provide information in a timely manner to the various users. The design incorporates a number of novel ideas, including a phase shifter design which uses a piezoelectric transducer (PET); a multi-frequency diplexer which incorporates two diplexers, one for Ku-Band and one for Ka-Band; and a radiating element which can operate at either the Ka-Band frequency or the Ku-Band frequency. The novel piezoelectric transducer design provides a significant reduction in insertion loss over existing technologies. In addition to a broad bandwidth and a cost reduction in the design, the dual diplexer design allows the system to readily switch operation between the Ku-Band and Ka-Band frequencies; and two different radiating elements designs (Vivaldi and LTSA) are being evaluated to provide operation at either Ku-Band or Ka-Band. The results of ongoing development activities of these technologies are also discussed in the paper. C1 USAF, Res Lab, Washington, DC 20330 USA. RP Foshee, J (reprint author), USAF, Res Lab, Washington, DC 20330 USA. NR 7 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 0-8194-4090-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4395 BP 108 EP 118 DI 10.1117/12.438278 PG 11 WC Computer Science, Information Systems; Engineering, Electrical & Electronic; Optics; Telecommunications SC Computer Science; Engineering; Optics; Telecommunications GA BT18S UT WOS:000172224000012 ER PT S AU Menon, SK Mendiratta, MG Dimiduk, DM AF Menon, SK Mendiratta, MG Dimiduk, DM BE Aindow, M Kiely, CJ TI Identification of oxidation products in multicomponent Nb-based intermetallics by EDS and WDS SO ELECTRON MICROSCOPY AND ANALYSIS 2001 SE INSTITUTE OF PHYSICS CONFERENCE SERIES LA English DT Article; Proceedings Paper CT Conference of the Electron-Microscopy-and-Analysis-Group CY SEP 05-07, 2001 CL UNIV DUNDEE, DUNDEE, SCOTLAND SP Electron Microscopy & Anal Grp, Royal Microscop Soc, Inst Mat HO UNIV DUNDEE AB High temperature structural Nb-Ti-Si based alloys contain alloying additions of Ge, Cr, Al and Hf. Some of these form oxides that are more thermodynamically stable than silica and consequently, complex oxides form during oxidation of these alloys. Mutual solubility among oxides, multiphase coexistence and segregation of the elements during oxidation lead to a very complex elemental distribution in oxidized samples. This paper provides examples of qualitative and quantitative identification of the microchemistry of phases ill Such Situations using elemental mapping in the SEM employing EDS and WDS. C1 USAF, Res Lab, Mat & Mfg Directorate, ML, Wright Patterson AFB, OH 45433 USA. Universal Energy Syst Inc, Dayton, OH 45432 USA. RP Menon, SK (reprint author), USAF, Res Lab, Mat & Mfg Directorate, ML, Wright Patterson AFB, OH 45433 USA. NR 5 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0951-3248 BN 0-7503-0812-5 J9 INST PHYS CONF SER PY 2001 IS 168 BP 211 EP 214 PG 4 WC Instruments & Instrumentation; Materials Science, Characterization & Testing; Microscopy; Physics, Multidisciplinary SC Instruments & Instrumentation; Materials Science; Microscopy; Physics GA BU50T UT WOS:000176200500051 ER PT S AU Bradley, CJ Collins, PJ Temple, MA Terzuoli, AJ Nesti, G Fortuny, J Lewis, GD AF Bradley, CJ Collins, PJ Temple, MA Terzuoli, AJ Nesti, G Fortuny, J Lewis, GD GP IEE IEE TI Issues in the calibration of bistatic RCS measurements SO ELEVENTH INTERNATIONAL CONFERENCE ON ANTENNAS AND PROPAGATION, VOLS 1 AND 2 SE IEE CONFERENCE PUBLICATIONS LA English DT Proceedings Paper CT 11th International Conference on Antennas and Propagation (ICAP 2001) CY APR 17-20, 2001 CL UNIV MANCHESTER, INST SCI & TECHNOL, MANCHESTER, ENGLAND SP IEE, Profess Network Antennas & Propagat, EUREL, IEEE, Inst Electr Informat & Commun, Engineers Japan, Inst Phys, Int Union Radio Sci HO UNIV MANCHESTER, INST SCI & TECHNOL AB A performance evaluation of several existing polarimetric calibration techniques for bistatic Radar Cross Section (RCS) measurements is in progress. Several calibration test objects, including: cylinders, a dihedral, a trihedral, sphere, and other noncanonical objects were measured at the European Microwave Signature Laboratory (EMSL), Joint Research Center (JRC), Ispra, Italy. Each object was measured with and without a systematic alignment error to determine effects on each of the calibration techniques considered. Three calibration types were designated, based on their capability to predict each coefficient of a 20-term error model of the antenna polarization distortion matrix (PDM). Bistatic RCS predictions were completed using a commercially available Moment Method code to validate the measurements for alignment precision and noise/distortion levels. C1 USAF, Inst Technol, Washington, DC 20330 USA. RP Bradley, CJ (reprint author), USAF, Inst Technol, Washington, DC 20330 USA. NR 5 TC 0 Z9 1 U1 0 U2 0 PU INST ELECTRICAL ENGINEERS INSPEC INC PI EDISON PA 379 THORNALL ST, EDISON, NJ 08837 USA SN 0537-9989 BN 0-85296-733-0 J9 IEE CONF PUBL PY 2001 IS 480 BP 293 EP 297 PG 5 WC Engineering, Electrical & Electronic; Remote Sensing; Telecommunications SC Engineering; Remote Sensing; Telecommunications GA BS84U UT WOS:000171223300066 ER PT S AU Quant, M Colburn, R AF Quant, M Colburn, R BE Sisti, AF Trevisani, DA TI Quantum information theory for model abstraction techniques SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 5th Enabling Technology for Simulation Science Conference CY APR 17-20, 2001 CL ORLANDO, FL SP SPIE DE information theory; model abstraction techniques; quantum information theory; classical information theory AB The intent of this paper to bring forward and explore a possible use of the emerging field of quantum information sciences to the modeling and simulation community. It is desired that this research will open new pathways and partnerships where quantum information theory may be applied to modeling techniques. The issue for a mixed resolution model/simulation is how one may provide for the correct data exchange between the differing levels of detail that exist among individual models. The concept behind model abstraction is to extract the essence of a high-resolution model to a level proper for the simulation. There is always a challenge to find a balance between speed of the simulation (lower resolution in the models) and the required level of detail to extract the intended information from the simulation. While computing speed is a quantity, which may be measured somewhat easily, the fitness of the detail extracted from a model is often questionable and subjectively measured. This paper will discuss the use of quantum information theory as a means to quantify differing levels of detail in mixed resolution simulations. An overview of information theory is provided in section 2. This is followed by a brief look at methods used to determine the fidelity of information passed as an abstracted model. C1 USAF, Res Lab, C4ISR Modeling & Simulat Branch, Rome, NY 13441 USA. RP Quant, M (reprint author), USAF, Res Lab, C4ISR Modeling & Simulat Branch, 525 Brooks Rd, Rome, NY 13441 USA. NR 19 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 0-8194-4062-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4367 BP 52 EP 61 AR UNSP 4367-05 DI 10.1117/12.440050 PG 10 WC Engineering, Aerospace; Computer Science, Theory & Methods; Optics SC Engineering; Computer Science; Optics GA BU10G UT WOS:000175015600006 ER PT S AU McQuay, WK AF McQuay, WK BE Sisti, AF Trevisani, DA TI Distributed collaborative environments for 21st century modeling & simulation SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 5th Enabling Technology for Simulation Science Conference CY APR 17-20, 2001 CL ORLANDO, FL SP SPIE DE collaboration; collaborative environment; simulation; analysis AB Distributed collaboration is an emerging technology that will significantly change how modeling and simulation is employed in 21(st) century organizations. Modeling and simulation (M&S ) is already an integral part of how many organizations conduct business and, in the future, will continue to spread throughout government and industry enterprises and across many domains from research and development to logistics to training to operations. This paper reviews research that is focusing on the open standards agent-based framework, product and process modeling, structural architecture, and the integration technologies - the glue to integrate the software components. A distributed collaborative environment is the underlying infrastructure that makes communication between diverse simulations and other assets possible and manages the overall flow of a simulation based experiment. The AFRL Collaborative Environment concept will foster a major cultural change in how the acquisition, training, and operational communities employ MS. C1 USAF, Res Lab, IFSD, Wright Patterson AFB, OH 45433 USA. RP McQuay, WK (reprint author), USAF, Res Lab, IFSD, 2241 Avion Circle, 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 0-8194-4062-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4367 BP 164 EP 173 AR UNSP 4367-18 DI 10.1117/12.440017 PG 10 WC Engineering, Aerospace; Computer Science, Theory & Methods; Optics SC Engineering; Computer Science; Optics GA BU10G UT WOS:000175015600017 ER PT S AU Gump, JW Kurker, RG Nalepka, JP AF Gump, JW Kurker, RG Nalepka, JP BE Sisti, AF Trevisani, DA TI JIMM: The next step for mission level models SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE V SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 5th Enabling Technology for Simulation Science Conference CY APR 17-20, 2001 CL ORLANDO, FL SP SPIE DE mission; model; SBA; SWEG; suppressor AB The (Simulation Based Acquisition) SBA process is one in which the planning, design, and test of a weapon system or other product is done through the more effective use of modeling and simulation, information technology, and process improvement. This process results in a product that is produced faster, cheaper, and more reliably than its predecessors. Because the SBA process requires realistic and detailed simulation conditions, it was necessary to develop a simulation tool that would provide a simulation environment acceptable for doing SBA analysis. The Joint Integrated Mission Model (JIMM) was created to help define and meet the analysis, test and evaluation, and training requirements of a Department of Defense program utilizing SBA. Through its generic nature of representing simulation entities, its data analysis capability, and its robust configuration management process, JIMM can be used to support a wide range of simulation applications as both a constructive and a virtual simulation tool. JIMM is a Mission Level Model (MLM). A MLM is capable of evaluating the effectiveness and survivability of a composite force of air and space systems executing operational objectives in a specific scenario against an integrated air and space defense system. Because MLMs are useful for assessing a system's performance in a realistic, integrated, threat environment, they are key to implementing the SBA process. JIMM is a merger of the capabilities of one legacy model, the Suppressor MLM, into another, the Simulated Warfare Environment Generator (SWEG) MLM. By creating a more capable MLM, JIMM will not only be a tool to support the SBA initiative, but could also provide the framework for the next generation of MLMs. C1 USAF, Elect Syst Ctr, CXCM PTI, Hanscom AFB, MA 01731 USA. RP Gump, JW (reprint author), USAF, Elect Syst Ctr, CXCM PTI, 45 Arnold St, Hanscom AFB, MA 01731 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 0-8194-4062-0 J9 P SOC PHOTO-OPT INS PY 2001 VL 4367 BP 305 EP 315 AR UNSP 4367-35 DI 10.1117/12.440034 PG 11 WC Engineering, Aerospace; Computer Science, Theory & Methods; Optics SC Engineering; Computer Science; Optics GA BU10G UT WOS:000175015600032 ER PT S AU Busch, TE AF Busch, TE BE Sisti, AF Trevisani, DA TI The use of modern control theory in military command and control SO ENABLING TECHNOLOGY FOR SIMULATION SCIENCE V SE Proceedings of SPIE LA English DT Proceedings Paper CT 5th Enabling Technology for Simulation Science Conference CY APR 17-20, 2001 CL ORLANDO, FL SP SPIE AB This paper discusses the use of modern control theoretic approaches in military command and control. The military enterprise is a highly dynamic and nonlinear environment. The desire on the part of military commanders to operate at faster operational tempos while still maintaining a stable and robust system, naturally leads to the consideration of a control theoretic approach to providing decision aids. I will present a brief history of the science of command and control of military forces and discuss how modem control theory might be applied to air operations. C1 USAF, Res Lab, Modeling & Simulat Branch, Rome, NY USA. RP Busch, TE (reprint author), USAF, Res Lab, Modeling & Simulat Branch, Rome, NY USA. NR 26 TC 0 Z9 0 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 0-8194-4062-0 J9 PROC SPIE PY 2001 VL 4367 BP 326 EP 329 DI 10.1117/12.440036 PG 4 WC Engineering, Aerospace; Computer Science, Theory & Methods; Optics SC Engineering; Computer Science; Optics GA BU10G UT WOS:000175015600034 ER PT B AU Bolia, RS Nelson, WT AF Bolia, RS Nelson, WT BE Harris, D TI Assessing patterns of head motion behaviour for adapting multisensory interfaces: qualitative and quantitative analyses and model specification SO ENGINEERING PSYCHOLOGY AND COGNITIVE ERGONOMICS VOLUME FIVE: AEROSPACE AND TRANSPORTATION SYSTEMS LA English DT Proceedings Paper CT 3rd International Conference on Engineering Psychology and Cognitive Ergonomics CY OCT 25-27, 2000 CL EDINBURGH, SCOTLAND AB Qualitative and quantitative measures of head motion were examined from two experiments in which pilots flew simulated fighter aircraft missions. One experiment assessed the efficacy of several combinations of dynamic multimodal interfaces for aircraft navigation; the other was designed to evaluate multi-sensory and adaptive interfaces for target acquisition. Models of head motion behaviour were developed and evaluated using data from Air Force pilots as they performed the simulated flight navigation and target detection and acquisition tasks. Results are discussed in terms of models of pilot head motion behaviour and the potential utility of head motion as a real-time indicator of when to adapt cockpit displays. C1 USAF, Res Lab, Washington, DC 20350 USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU ASHGATE PUBLISHING LTD PI ALDERSHOT PA GOWER HOUSE, CROFT ROAD, ALDERSHOT GU11 3HR, ENGLAND BN 0-7546-1337-2 PY 2001 BP 109 EP 116 PG 8 WC Ergonomics; Psychology, Applied; Psychology, Experimental; Transportation SC Engineering; Psychology; Transportation GA BU72T UT WOS:000176846500013 ER PT S AU Zydallis, JB Van Veldhuizen, DA Lamont, GB AF Zydallis, JB Van Veldhuizen, DA Lamont, GB BE Zitzlet, E Deb, K Thiele, L Coello, CAC Corne, D TI A statistical comparison of multiobjective evolutionary algorithms including the MOMGA-II SO EVOLUTIONARY MULTI-CRITERION OPTIMIZATION, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT 1st International Conference on Evolutioary Multi-Criterion Optimization (EMO 2001) CY MAR 07-09, 2001 CL SWISS FED INST TECHNOL, ZURICH, SWITZERLAND HO SWISS FED INST TECHNOL AB Many real-world scientific and engineering applications involve finding innovative solutions to "hard" Multiobjective Optimization Problems (MOP). Various Multiobjective Evolutionary Algorithms (MOEA) have been developed to obtain MOP Pareto solutions. A particular exciting MOEA is the MOMGA which is an extension of the single-objective building block (BB) based messy Genetic Algorithm. The intent of this discussion is to illustrate that modifications made to the Multi-Objective messy GA (MOMGA) have further improved its efficiency resulting in the MOMGA-II. The MOMGA-II uses a probabilistic BB approach to initializing the population referred to as Probabilistic ally Complete Initialization. This has the effect of improving the efficiency of the MOMGA through the reduction of computational bottle-necks. Similar statistical results have been obtained using the MOMGA-II as compared to the results of the original MOMGA as well as those obtained by other MOEAs as tested with standard generic MOP test suites. C1 USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. USAF, Res Lab, Opt Radiat Branch, Brooks AFB, TX 78235 USA. RP Zydallis, JB (reprint author), USAF, Inst Technol, Dept Elect & Comp Engn, Wright Patterson AFB, OH 45433 USA. NR 11 TC 12 Z9 12 U1 0 U2 0 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-41745-1 J9 LECT NOTES COMPUT SC PY 2001 VL 1993 BP 226 EP 240 PG 15 WC Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA BU11K UT WOS:000175042500016 ER PT J AU Li, T Carrano, JC Eiting, CJ Grudowski, PA Lambert, DJH Kwon, HK Dupuis, RD Campbell, JC AF Li, T Carrano, JC Eiting, CJ Grudowski, PA Lambert, DJH Kwon, HK Dupuis, RD Campbell, JC TI Design of a resonant-cavity-enhanced p-i-n GaN/AlxGa1-xN photodetector SO FIBER AND INTEGRATED OPTICS LA English DT Article DE ultraviolet photodetector; resonant cavity; III-V nitrides; Bragg reflector; interface roughness ID CHEMICAL-VAPOR-DEPOSITION; EPITAXIAL LAYERS; GAN; FILMS AB A resonant-cavity-enhanced p-i-n photodetector has been designed and analyzed to operate at a wavelength of 360 nm based on the AlxGa1-xN material system. The novel approach has been adopted of using epitaxial AlN/AlxGa1-xN quarter-wave stacks as the distributed Bragg reflector that serves as the front mirror. An AlxGa1-xN absorptive filter layer is incorporated in suppress all but one resonant mode to ensure single, narrow-band operation. This device structure is projected to achieve wavelength selective, high speed, and high quantum efficiency operation in the ultraviolet. MOCVD-grown 6 1/2-pair AlN/AlxGa1-xN Bragg reflectors with peak reflectivities of similar to 57% have been demonstrated The spectral reflectivity data are found to be in agreement with results of S-matrix simulations with scattering due to interface roughness taken into account. C1 Univ Texas, Dept Elect & Comp Engn, Ctr Microelect Res, Austin, TX 78712 USA. USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. USA, Res Lab, Adelphi, MD USA. RP Campbell, JC (reprint author), Univ Texas, Dept Elect & Comp Engn, Ctr Microelect Res, UT-PRC-MER R9950, Austin, TX 78712 USA. NR 18 TC 4 Z9 5 U1 1 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0146-8030 J9 FIBER INTEGRATED OPT JI Fiber Integrated Opt. PY 2001 VL 20 IS 2 BP 125 EP 131 DI 10.1080/01468030151076026 PG 7 WC Optics SC Optics GA 414UN UT WOS:000167684700002 ER PT J AU Thirunarayan, K Ewing, RL AF Thirunarayan, K Ewing, RL TI Structural operational semantics for a portable subset of behavioral VHDL-93 SO FORMAL METHODS IN SYSTEM DESIGN LA English DT Article DE hardware description languages (VHDL); formal semantics (of VHDL-93); formal specification (of VHDL-93 simulation cycle); shared variables (in VHDL-93) and portability AB Goossens defined structural operational semantics for a subset of VHDL-87 and proved that the parallelism present in VHDL is benign. We extend this work to include VHDL-93 features such as shared variables and postponed processes that change the underlying semantic model. In the presence of shared variables, non-deterministic execution of VHDL-93 processes destroys the unique meaning property. We identify and characterize a class of portable VHDL-93 descriptions for which unique meaning property can be salvaged. We analyze the computability of the portability condition and show that portability checks are neither local nor static. Our formal specification can serve as a correctness criteria for a VHDL-93 simulator or can be used as a basis for coding a simulator. C1 Wright State Univ, Dept Comp Sci & Engn, Dayton, OH 45435 USA. USAF, Res Lab, Informat Directorate, Wright Patterson AFB, OH 45433 USA. NR 21 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 0925-9856 J9 FORM METHOD SYST DES JI Form. Methods Syst. Des. PD JAN PY 2001 VL 18 IS 1 BP 69 EP 88 DI 10.1023/A:1008786720393 PG 20 WC Computer Science, Theory & Methods SC Computer Science GA 396AG UT WOS:000166613700003 ER PT B AU Goetz, RL Jata, KV AF Goetz, RL Jata, KV BE Jata, KV Mahoney, MW Mishra, RS Semiatin, SL Field, DP TI Modeling friction stir welding of titanium and aluminum alloys SO FRICTION STIR WELDING AND PROCESSING LA English DT Proceedings Paper CT 1st Symposium on Friction Stir Welding and Processing held in Conjunction with the Fall Meeting of the TMS CY NOV, 2001 CL INDIANAPOLIS, IN SP TMS, Mat Process & Mfg Div, Shaping & Forming Comm, Texture & Anisotropy Comm AB Friction stir welding (FSW) is a solid state welding process primarily for aluminum alloys and aerospace applications. However, there is also interest in using FSW for higher temperature aerospace materials such as titanium alloys. In light of this, FSW of Ti-6Al-4V was modeled and compared to aluminum alloys using a finite element model. The model was used to predict the tool and workpiece temperatures for various tool rpm's and plunge rates, as well as loads and deformation behavior. The effect of various tool materials was also examined with respect to tool and workpiece temperature response. C1 USAF, Res Lab, AFRL MLLM, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Goetz, RL (reprint author), USAF, Res Lab, AFRL MLLM, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 9 TC 15 Z9 15 U1 1 U2 6 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-502-6 PY 2001 BP 35 EP 42 PG 8 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA BT49C UT WOS:000173132500004 ER PT B AU John, R Jata, KV AF John, R Jata, KV BE Jata, KV Mahoney, MW Mishra, RS Semiatin, SL Field, DP TI Residual stress effects on near-threshold fatigue crack growth in friction stir welds SO FRICTION STIR WELDING AND PROCESSING LA English DT Proceedings Paper CT 1st Symposium on Friction Stir Welding and Processing held in Conjunction with the Fall Meeting of the TMS CY NOV, 2001 CL INDIANAPOLIS, IN SP TMS, Mat Process & Mfg Div, Shaping & Forming Comm, Texture & Anisotropy Comm AB Friction stir welding is being explored as a potential tool for manufacturing aluminum aerospace structures. Several joint configurations, butt, lap and fillet joints have been produced in the production of such exploratory structures. Research work on S-N fatigue and fatigue crack growth in the weld zone is required to provide an understanding and tools to assess the damage tolerance issues in friction stir welded joints and structures, In this work, results of a study conducted on near-threshold fatigue crack growth in friction stir welded aluminum alloy 7050-T7451 are presented. Tests were conducted on weld coupons as a function of specimen geometry (compact tension and center-crack tension) and stress ratio to understand the effects of residual stresses in the heat affected zone (HAZ) of the alloy. Residual stresses were measured on a friction stir welded plate prior to testing. The crack growth results show that residual stresses play a key role in the crack growth parallel to the weld-path in the HAZ Although friction stir welding process induced low residual stresses in the welds, they are large enough to affect the near-threshold fatigue crack growth. At low stress ratio, the fatigue threshold in the HAZ was either higher or lower than that of the baseline material depending on the geometry. At high stress ratio, the differences due to the geometry vanish. Center-crack tension geometry is less sensitive to the residual stress effects compared to the compact tension geometry. Crack growth analysis using equivalent residual stresses was used to determine the residual stress intensity factor and predict stress ratio effects. C1 USAF, Res Lab, AFRL MLLM, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP John, R (reprint author), USAF, Res Lab, AFRL MLLM, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 16 TC 2 Z9 2 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-502-6 PY 2001 BP 57 EP 69 PG 13 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA BT49C UT WOS:000173132500006 ER PT B AU Jata, KV Seetharaman, V Semiatin, SL AF Jata, KV Seetharaman, V Semiatin, SL BE Jata, KV Mahoney, MW Mishra, RS Semiatin, SL Field, DP TI High temperature deformation of friction-stir-processed aluminum-lithium alloy AF/C458 SO FRICTION STIR WELDING AND PROCESSING LA English DT Proceedings Paper CT 1st Symposium on Friction Stir Welding and Processing held in Conjunction with the Fall Meeting of the TMS CY NOV, 2001 CL INDIANAPOLIS, IN SP TMS, Mat Process & Mfg Div, Shaping & Forming Comm, Texture & Anisotropy Comm AB Weld joints produced by friction-stir welding display three zones that differ in grain structure: (i) a stir zone consisting of fine, equiaxed, continuously recrystallized grains, (ii) a thermomechanically-affected zone consisting of grains that are severely bent and drawn into the weld, and (iii) a heat-affected zone that retains the original size and morphology of the parent metal. Recently, the friction-stir technique has been proposed as a means to refine the grain size of the parent material for several classes of aluminum alloys. The properties of recrystallized material produced by friction-stir processing is especially interesting with regard to the high temperature deformation behavior. In this work, the high temperature plastic flow characteristics of friction-stir processed aluminum-lithium alloy AF/C458 and the stability of the fine grain microstructure were investigated. The refined structure led to superplastic behavior (i.e., m values > 0.3) at temperatures of 480 and 500degreesC and strain rates below 10(-3) s(-1). Limited grain growth was observed as well, thus explaining the minimal variation of rn with strain. C1 USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, Wright Patterson AFB, OH 45433 USA. RP Jata, KV (reprint author), USAF, Res Lab, Mat & Mfg Directorate, AFRL MLLM, 2230 10th St, Wright Patterson AFB, OH 45433 USA. RI SEMIATIN, SHELDON/E-7264-2017 NR 3 TC 3 Z9 3 U1 0 U2 1 PU MINERALS, METALS & MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086-7514 USA BN 0-87339-502-6 PY 2001 BP 195 EP 204 PG 10 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA BT49C UT WOS:000173132500018 ER PT S AU Welch, R Jenkins, T Neidhard, B Kehias, L Quach, T Watson, P Worley, R Barsky, M Sandhu, R Wojtowicz, M AF Welch, R Jenkins, T Neidhard, B Kehias, L Quach, T Watson, P Worley, R Barsky, M Sandhu, R Wojtowicz, M GP IEEE IEEE TI Low noise hybrid amplifier using AlGaN/GaN power HEMT devices SO GAAS IC SYMPOSIUM, TECHNICAL DIGEST 2001 SE TECHNICAL DIGEST - IEEE GALLIUM ARSENIDE INTEGRATED CIRCUIT SYMPOSIUM LA English DT Proceedings Paper CT 23rd Annual IEEE GaAs IC Symposium CY OCT 21-24, 2001 CL BALTIMORE, MD SP IEEE Electron Devices Soc, IEEE Microwave Theory & Tech Soc, IEEE Solid State Circuits Soc AB This work reports on efforts to demonstrate AlGaN/GaN Low Noise Amplifiers (LNAs) in epitaxial material designed to build power transistors. The hybrid LNA circuit produced a noise figure of 3 dB, a gain of 8.5 dB, an input return loss of -6.5 dB and an output return loss of -9 dB at 4 GHz. Further, devices in an enhanced process have improved noise characteristics and more realizable match conditions. These device enhancements will enable robust X-band LNA demonstrations. C1 USAF, Res Lab, Sensors Directorate, Electron Devices Branch, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, Sensors Directorate, Electron Devices Branch, 2241 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1064-7775 BN 0-7803-6663-8 J9 TG IEEE GAL ARS PY 2001 BP 153 EP 155 DI 10.1109/GAAS.2001.964367 PG 3 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA BT68H UT WOS:000173723800034 ER PT S AU Quach, T Watson, P Okamura, W Kaneshiro, E Gutierrez-Aitken, A Block, T Eldredge, J Jenkins, T Kehias, L Oki, A Sawdai, D Welch, R Worley, R AF Quach, T Watson, P Okamura, W Kaneshiro, E Gutierrez-Aitken, A Block, T Eldredge, J Jenkins, T Kehias, L Oki, A Sawdai, D Welch, R Worley, R GP IEEE IEEE TI Broadband Class-E power amplifier for space radar application SO GAAS IC SYMPOSIUM, TECHNICAL DIGEST 2001 SE TECHNICAL DIGEST - IEEE GALLIUM ARSENIDE INTEGRATED CIRCUIT SYMPOSIUM LA English DT Proceedings Paper CT 23rd Annual IEEE GaAs IC Symposium CY OCT 21-24, 2001 CL BALTIMORE, MD SP IEEE Electron Devices Soc, IEEE Microwave Theory & Tech Soc, IEEE Solid State Circuits Soc AB We report on a broadband high efficiency power amplifier using Indium Phosphide (InP) double heterojunction bipolar transistor (DHBT) technology. The amplifier demonstrated a record bandwidth for a Class-E power amplifier at X-Band. This circuit achieved 49-58% PAE, 18.5-23.9 dBm output power, and 9.6-10.5 dB gain across 9-11 GHz. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Quach, T (reprint author), USAF, Res Lab, 2241 Av Circle,Bldg 620, Wright Patterson AFB, OH 45433 USA. NR 7 TC 2 Z9 2 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1064-7775 BN 0-7803-6663-8 J9 TG IEEE GAL ARS PY 2001 BP 209 EP 212 DI 10.1109/GAAS.2001.964380 PG 4 WC Engineering, Electrical & Electronic; Optics; Telecommunications SC Engineering; Optics; Telecommunications GA BT68H UT WOS:000173723800047 ER PT B AU Ganguly, BN Scofield, JD Bletzinger, P AF Ganguly, BN Scofield, JD Bletzinger, P BE Christophorou, LG Olthoff, JK TI The use of SF6 as a plasma processing gas SO GASEOUS DIELECTRICS IX LA English DT Proceedings Paper CT 9th International Symposium on Gaseous Dielectrics CY MAY 21-25, 2001 CL ELLICOTT CITY, MD SP Natl Inst Stand & Technol, ABB, USAF Res Lab, Hitachi Ltd, Kansai Elect Power Co, Toshiba Corp, IEEE Dielect & Elect Insulat Soc ID SILICON DIOXIDE; DISCHARGES; IMPEDANCE; FLUORINE; CF4 C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Ganguly, BN (reprint author), USAF, Res Lab, 2045 5th St,Ste 13, Wright Patterson AFB, OH 45433 USA. NR 14 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 0-306-46705-4 PY 2001 BP 95 EP 101 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Atomic, Molecular & Chemical SC Engineering; Physics GA BT88X UT WOS:000174363400013 ER PT B AU Horwath, J Schweickart, D Penno, R AF Horwath, J Schweickart, D Penno, R BE Christophorou, LG Olthoff, JK TI Fast time resolved measurement and simulation of corona SO GASEOUS DIELECTRICS IX LA English DT Proceedings Paper CT 9th International Symposium on Gaseous Dielectrics CY MAY 21-25, 2001 CL ELLICOTT CITY, MD SP Natl Inst Stand & Technol, ABB, USAF Res Lab, Hitachi Ltd, Kansai Elect Power Co, Toshiba Corp, IEEE Dielect & Elect Insulat Soc ID FLUX-CORRECTED TRANSPORT C1 USAF, Res Lab, AFRL PRPC, Wright Patterson AFB, OH 45433 USA. RP USAF, Res Lab, AFRL PRPC, 2645 5th St B450, Wright Patterson AFB, OH 45433 USA. EM John.Horwath@wpafb.af.mil; daniel.schweickart@wpafb.af.mil 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 0-306-46705-4 PY 2001 BP 181 EP 185 PG 5 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Atomic, Molecular & Chemical SC Engineering; Physics GA BT88X UT WOS:000174363400025 ER PT B AU Burke, WJ AF Burke, WJ BE Christophorou, LG Olthoff, JK TI Some considerations of near-Earth space as a gaseous dielectric SO GASEOUS DIELECTRICS IX LA English DT Proceedings Paper CT 9th International Symposium on Gaseous Dielectrics CY MAY 21-25, 2001 CL ELLICOTT CITY, MD SP Natl Inst Stand & Technol, ABB, USAF Res Lab, Hitachi Ltd, Kansai Elect Power Co, Toshiba Corp, IEEE Dielect & Elect Insulat Soc C1 USAF, Res Lab, Space Vehicles Directorate, Hanscom AFB, MA 01731 USA. RP Burke, WJ (reprint author), USAF, Res Lab, Space Vehicles Directorate, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 13 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 0-306-46705-4 PY 2001 BP 187 EP 196 PG 10 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Atomic, Molecular & Chemical SC Engineering; Physics GA BT88X UT WOS:000174363400026 ER PT J AU Atkinson, EJ Hall, D de Andrade, M AF Atkinson, EJ Hall, D de Andrade, M TI A comparison of software packages that assess linkage using a variance components approach SO GENETIC EPIDEMIOLOGY LA English DT Article; Proceedings Paper CT Genetic Analysis Workshop 12 (GAW12) CY OCT 23-26, 2000 CL SAN ANTONIO, TEXAS DE covariates; multipoint linkage; quantitative trait; variance components ID GENOME-WIDE SEARCH; SERUM IGE LEVELS; PEDIGREES; ASTHMA; MARKERS; TRAITS; GENE AB We report single-point and multipoint results from three statistical genetics software packages using a variance components approach for quantitative traits. When possible, we have shown the effects of covariates. Results from GENEHUNTER, SOLAR, and ACT software packages are compared for the quantitative trait immunoglobulin E (IgE) using chromosome 5 asthma familial data from Oxfordshire (England), Perth (Australia), and Freiburg (Germany), and using the genome-wide German data. Although few differences among variance components results for GENEHUNTER, SOLAR, and ACT were detected on a limited region of chromosome 5, these packages showed larger disagreement in the German data for chromosomes 1, 9, and 14. (C) 2001 Wiley-Liss, Inc. C1 Mayo Clin, Biostat Sect, Dept Hlth Sci Res, Rochester, MN 55905 USA. USAF Acad, Dept Biol, Colorado Springs, CO USA. RP de Andrade, M (reprint author), Mayo Clin, Biostat Sect, Dept Hlth Sci Res, 200 1st St SW,Harwick 7, Rochester, MN 55905 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0741-0395 J9 GENET EPIDEMIOL JI Genet. Epidemiol. PY 2001 VL 21 SU 1 BP S81 EP S88 PG 8 WC Genetics & Heredity; Mathematical & Computational Biology SC Genetics & Heredity; Mathematical & Computational Biology GA 480LK UT WOS:000171462700018 PM 11793783 ER PT J AU Bhattacharyya, A Basu, S Groves, KM Valladares, CE Sheehan, R AF Bhattacharyya, A Basu, S Groves, KM Valladares, CE Sheehan, R TI Dynamics of equatorial F region irregularities from spaced receiver scintillation observations SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID BOTTOMSIDE SINUSOIDAL IRREGULARITIES; SPREAD-F; DRIFTS; RADAR; SYSTEM; PERU AB Spaced receiver observations of amplitude scintillations on a 244 MHz signal, at an equatorial station, have been used to study random temporal changes associated with the scintillation-producing irregularities and the variability of their motion. The computed drift of the scintillation pattern shows the presence of velocity structures associated with equatorial bubbles in the early phase of their development. On magnetically quiet days, after 22:00 LT, the estimated drifts fall into a pattern which is close to that of the ambient plasma drift. There is considerable decorrelation between the two signals until 22:00 LT. The power spectra of the most highly correlated scintillations recorded by spaced receivers indicate that the associated irregularities are confined to a thin layer on the bottomside of the equatorial F region. This suggests that file convection pattern associated with bottomside irregularities is stable due to the dominance of ion-neutral collisions over ion inertia. C1 USAF, Res Lab, Space Vehicles Directorate, AFRL,VSBI, Hanscom AFB, MA 01731 USA. Boston Coll, Inst Sci Res, Newton, MA 02159 USA. Indian Inst Geomagnetism, Bombay 400005, Maharashtra, India. RP Bhattacharyya, A (reprint author), USAF, Res Lab, Space Vehicles Directorate, AFRL,VSBI, 29 Randolph Rd, Hanscom AFB, MA 01731 USA. NR 19 TC 45 Z9 45 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 1 PY 2001 VL 28 IS 1 BP 119 EP 122 DI 10.1029/2000GL012288 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 390JD UT WOS:000166291200032 ER PT J AU Sato, N Murata, Y Yamagishi, H Yukimatu, AS Kikuchi, M Watanabe, M Makita, K Yang, HG Liu, RY Rich, FJ AF Sato, N Murata, Y Yamagishi, H Yukimatu, AS Kikuchi, M Watanabe, M Makita, K Yang, HG Liu, RY Rich, FJ TI Enhancement of optical aurora triggered by the solar wind negative pressure impulse (SI-) SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SUDDEN COMMENCEMENT; PROPAGATION; SHAPE; CUSP; SSC AB A geomagnetic negative sudden impulse (SI-) occurred on 3 August 1997 in association with a sudden decrease of solar wind dynamic pressure. The discrete auroras observed by an all-sky TV imager at Zhongshan in Antarctica (magnetic latitude is similar to 74.5 degreesS) suddenly enhanced their luminosity and moved poleward at the time of the SI-. Following the primary enhancement, three cycles of quasi-periodic luminosity pulsations were observed with periods of about 10-14 min and their average position drifted equatorward. The luminosity pulsations showed one-to-one correspondence with the magnetic pulsations, with the characteristic features of a field-line resonance, The low-altitude DMSP-F13 satellite was almost directly over Zhongshan and observed accelerated electron precipitation with an inverted 'V' structure and an upward field-aligned current. These signatures suggest that the solar wind negative pressure impulse triggered a field-lint resonance of the geomagnetic field. The resonance caused the upward and downward field-aligned current sheets, and the field-aligned electron acceleration. C1 Natl Inst Polar Res, Tokyo 1738515, Japan. Takushoku Univ, Hachioji, Tokyo 1930944, Japan. Polar Res Inst China, Shanghai 200129, Peoples R China. USAF, Res Lab, Hanscom AFB, MA 01731 USA. RP Sato, N (reprint author), Natl Inst Polar Res, 9-10 Kaga 1 Chome, Tokyo 1738515, Japan. NR 14 TC 16 Z9 20 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD JAN 1 PY 2001 VL 28 IS 1 BP 127 EP 130 DI 10.1029/2000GL003742 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 390JD UT WOS:000166291200034 ER PT S AU Jabs, JL Chang, CH Tingley, R AF Jabs, JL Chang, CH Tingley, R GP IEEE IEEE TI Performance of a very low power wireless protocol SO GLOBECOM '01: IEEE GLOBAL TELECOMMUNICATIONS CONFERENCE, VOLS 1-6 SE IEEE Global Telecommunications Conference (Globecom) LA English DT Proceedings Paper CT IEEE Global Telecommunications Conference (GLOBECOM 01) CY NOV 25-29, 2001 CL SAN ANTONIO, TX SP IEEE, Fujitsu Network Commun, SBC Commun Inc, Siemens, CIENA Corp, Corning Cable Syst, Nortel Networks, Tellabs AB The IEEE 802.11 standard [1] falls short in meeting the low power requirements of many applications not directly associated with typical LAN (Local Area Network) use. In 1998 the Charles Stark Draper Laboratory began research into a United States Navy program named Reduced Ships-Crew by Virtual Presence (RSVP). This program calls for numerous battery-powered sensors to wirelessly communicate with a ship's wired backbone. These sensors must operate reliably for a period of 10 years without battery replacement. This paper compares the power performance of IEEE 802.11 against a Draper proprietary protocol in an environment characterized by low noise and slow-fat Rayleigh fading and shows that devices using the RSVP protocol can theoretically operate up to 100 times longer than using the IEEE standard. C1 USAF, Washington, DC 20330 USA. RP Jabs, JL (reprint author), USAF, Washington, DC 20330 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 1930-529X BN 0-7803-7206-9 J9 GLOB TELECOMM CONF PY 2001 BP 2825 EP 2831 PG 7 WC Optics; Telecommunications SC Optics; Telecommunications GA BV36Z UT WOS:000178714800544 ER PT J AU Christ, JA AF Christ, JA TI On capture width and capture zone gaps in multiple well systems - Discussion SO GROUND WATER LA English DT Editorial Material C1 USAF, Minot AFB, ND 58704 USA. RP Christ, JA (reprint author), USAF, 126 Coral Ct 1, Minot AFB, ND 58704 USA. NR 1 TC 2 Z9 2 U1 0 U2 1 PU GROUND WATER PUBLISHING CO PI WESTERVILLE PA 601 DEMPSEY RD, WESTERVILLE, OH 43081 USA SN 0017-467X J9 GROUND WATER JI Ground Water PD JAN-FEB PY 2001 VL 39 IS 1 BP 2 EP 2 PG 1 WC Geosciences, Multidisciplinary; Water Resources SC Geology; Water Resources GA 389ZD UT WOS:000166267800002 ER PT S AU Robertson, L Johnson, C Tipton, C Jordan, D AF Robertson, L Johnson, C Tipton, C Jordan, D BE Culp, RD Schira, CN TI Acquisition, Tracking and Pointing of a dynamic target using compensated beacons SO GUIDANCE AND CONTROL 2001 SE ADVANCES IN THE ASTRONAUTICAL SCIENCES LA English DT Proceedings Paper CT Annual American-Astronautical-Society Rocky-Mountain Guidance and Control Conference CY JAN 31-FEB 04, 2001 CL BRECKENRIDGE, CO SP Amer Astronaut Soc AB This paper describes the Acquisition, Tracking and Pointing (ATP) activities of the Non-Cooperative Dynamic Compensation Experiment (NoDyCE). The purpose of this experiment was to demonstrate compensating scoring against a dynamic aircraft target board using active track and Adaptive Optics (AO) beacons originating from North Oscura Peak. This paper will cover three major parts of the experiment as they relate to ATP: one, discussion of the ATP hardware used for NoDyCE, two, wave optics simulation results of expected atmospheric turbulence versus jitter, and three, experiment results and sensitivities of the fine track system to various parameter changes. C1 USAF, Res Lab, Directed Energy Directorate, DEBA, Kirtland AFB, NM 87117 USA. RP Robertson, L (reprint author), USAF, Res Lab, Directed Energy Directorate, DEBA, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 2 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 0-87703-479-6 J9 ADV ASTRONAUT SCI PY 2001 VL 107 BP 555 EP 571 PG 17 WC Engineering, Aerospace; Astronomy & Astrophysics SC Engineering; Astronomy & Astrophysics GA BS56F UT WOS:000170334900034 ER PT J AU Himberger, JR Himberger, LC AF Himberger, JR Himberger, LC TI Accuracy of drawing blood through infusing intravenous lines SO HEART & LUNG LA English DT Article AB OBJECTIVE: To determine the usefulness of peripheral intravenous lines as an alternative route for obtaining blood samples. DESIGN: Quasiexperimental, SETTING: Wilford Hall Medical Center, a regional level I trauma center and military teaching hospital in San Antonio, Tex. SAMPLE: A convenience sample of 64 subjects was enrolled between September 1997 and June 1998. OUTCOME MEASURES: Comparative analysis of a complete blood count and chemistry, using the patients as their own control, on the same Coulter Analyzer and Boelrringer Mannheim/Hitachi 747-200. RESULTS: A total of 559 values were evaluated. Only 2.5% of the specimens exceeded the Clinical Laboratory Improvement Act standards. None of the values was clinically significant. CONCLUSION: Intravenous devices, if used properly. are reliable tools for blood specimen collection. They yield accurate analyte levels that may used in the treatment of patients. C1 959th Surg Operat Squadron, Emergency Dept, Med Wing 59, Andrews AFB, MD USA. RP Himberger, JR (reprint author), USAF, NC 4030-1 Ashwood Circle, Andrews AFB, MD 20762 USA. NR 24 TC 10 Z9 10 U1 0 U2 0 PU MOSBY, INC PI ST LOUIS PA 11830 WESTLINE INDUSTRIAL DR, ST LOUIS, MO 63146-3318 USA SN 0147-9563 J9 HEART LUNG JI Heart Lung PD JAN-FEB PY 2001 VL 30 IS 1 BP 66 EP 73 DI 10.1067/mhl.2001.110535 PG 8 WC Cardiac & Cardiovascular Systems; Nursing; Respiratory System SC Cardiovascular System & Cardiology; Nursing; Respiratory System GA 394NW UT WOS:000166531000009 PM 11174369 ER PT S AU Task, HL AF Task, HL BE Lewandowski, RJ Haworth, LA Girolamo, HJ Rash, CE TI Night vision goggle visual acuity assessment: Results of an interagency test SO HELMET- AND HEAD-MOUNTED DISPLAYS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Helmet- and Head-Mounted Displays VI CY APR 16-17, 2001 CL ORLANDO, FL SP SPIE AB There are several parameters that are used to characterize the quality of a night vision goggle (NVG) such as resolution, gain, field-of-view, visual acuity, etc. One of the primary parameters is visual acuity or resolution of the NVG. These two terms are often used interchangeably primarily because of the measurement methods employed. The objectives of this paper are to present: 1) an argument as to why NVG visual acuity and resolution should he considered as distinctly different parameters, 2) descriptions of different methods of measuring visual acuity and resolution, and 3) the results of a blind test by several agencies to measure the resolution of the same two NVGs (four oculars). C1 USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Task, HL (reprint author), USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. NR 9 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 0-8194-4056-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4361 BP 130 EP 137 DI 10.1117/12.437987 PG 8 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT20P UT WOS:000172264400014 ER PT S AU Angel, SD AF Angel, SD BE Lewandowski, RJ Haworth, LA Girolamo, HJ Rash, CE TI NVG eyepiece focus (diopter) study SO HELMET- AND HEAD-MOUNTED DISPLAYS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Helmet- and Head-Mounted Displays VI CY APR 16-17, 2001 CL ORLANDO, FL SP SPIE DE diopter; dioptometer; field of view; night vision goggles; AN/AVS-9; Panoramic Night Vision Goggle (PNVG); Integrated Panoramic Night Vision Goggle (IPNVG); eyepiece diopter setting AB Technology is advancing to the point where night vision goggle designs being developed have wider fields of view to help achieve an increase in situational awareness. The appropriate diopter setting for the eyepiece of these goggles needed to be determined. Aircrew members were surveyed to determine the range of diopter settings they-were using. In order to determine what fixed setting would work the best, two diopter settings were chosen (-1.0 and -0.5) to preset aircrew members' goggles. The aircrew flew with these presettings and then filled out a 14-question survey about the diopter settings. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Angel, SD (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 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 0-8194-4056-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4361 BP 138 EP 147 DI 10.1117/12.437988 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT20P UT WOS:000172264400015 ER PT S AU Marasco, PL Task, HL AF Marasco, PL Task, HL BE Lewandowski, RJ Haworth, LA Girolamo, HJ Rash, CE TI The measurement of visual performance through scattering visors and aerospace transparencies SO HELMET- AND HEAD-MOUNTED DISPLAYS VI SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Helmet- and Head-Mounted Displays VI CY APR 16-17, 2001 CL ORLANDO, FL SP SPIE DE visors; visual performance; transparencies; helmet-mounted displays AB Light scattered from helmet visors and aerospace transparencies is known to reduce visual performance. One popular measurement technique, maintained by the American Society for Testing and Materials, is ASTM D 1003. It is a standard procedure used to measure haze inherent in transparent material, which is defined as the percent of the total transmitted light that is scattered. However, research has shown that visual acuity measured through several different types of helmet visors does not correlate well with visor haze. This is most likely due to the fact that the amount of light scattered from a transparent material depends heavily on the light illuminating the transparency and on the viewing geometry, behavior that ASTM D 1003 does not characterize. Scattered light causes transparent parts to appear luminescent and imparts a veiling luminance when superimposed over a target, reducing target contrast and inducing a visual performance loss. This paper describes an experiment in which threshold target background luminance, the luminance at which a target was barely visible, was measured for a number of observers viewing a Landolt C target through several levels of veiling luminance. Threshold luminance was examined for predictable behavior with respect to veiling luminance. C1 USAF, Res Lab, Human Effect Directorate, AFRL HECV, Wright Patterson AFB, OH 45433 USA. RP Marasco, PL (reprint author), USAF, Res Lab, Human Effect Directorate, AFRL HECV, 2255 H St,Rm 300, Wright Patterson AFB, OH 45433 USA. NR 10 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4056-6 J9 P SOC PHOTO-OPT INS PY 2001 VL 4361 BP 188 EP 197 DI 10.1117/12.437994 PG 10 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT20P UT WOS:000172264400020 ER PT S AU Jenkins, JC Havig, PR Geiselman, EE AF Jenkins, JC Havig, PR Geiselman, EE BE Lewandowski, RJ Haworth, LA Girolamo, HJ Rash, CE TI A Non-Distributed Flight Reference symbology for helmet-mounted display use during off-boresight viewing: a dynamic task evaluation SO HELMET- AND HEAD-MOUNTED DISPLAYS VI SE Proceedings of SPIE LA English DT Proceedings Paper CT Conference on Helmet- and Head-Mounted Displays VI CY APR 16-17, 2001 CL ORLANDO, FL SP SPIE DE helmet-mounted display; symbology; attitude; flight reference; off-boresight AB This paper describes an evaluation of the Non-Distributed Flight Reference (NDFR) helmet-mounted display (HMD) symbology for a simulated aircraft-maneuvering task. In this experiment, pilot performance concerning interpretability of three symbol sets (standard HUD, VCATS, and NDFR) during a simulated flying maneuver was assessed. Pilots observed two, five-minute dynamic flight paths for each of the three symbol sets of interest. At random intervals, the display went blank and the pilot was asked a question regarding one of the five flight parameters previously displayed: either airspeed, heading, altitude, bank, or pitch. The pilot answered the question and then provided a confidence rating on a scale of 0 to 5, and the flight path then continued. Two dynamic flight paths were used, termed low and high, referring to the difficulty of the flight path. The study was conducted using 12 pilots recruited from Wright-Patterson AFB and McEntire ANGS. Since the initial evaluation of the NDFR(1) showed an interpretation advantage over VCATS and standard HUD when displayed briefly, this follow-on study sought to quantify how much of that advantage remained when the pilot task became more operationally relevant. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. RP Jenkins, JC (reprint author), USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. 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 0-8194-4056-6 J9 PROC SPIE PY 2001 VL 4361 BP 237 EP 250 DI 10.1117/12.437999 PG 14 WC Engineering, Aerospace; Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT20P UT WOS:000172264400025 ER PT S AU Sharma, SK Snyder, CE Gschwender, LJ Liang, JC Schreiber, BF AF Sharma, SK Snyder, CE Gschwender, LJ Liang, JC Schreiber, BF BE Totten, GE Wills, DK Feldmann, DG TI Rust inhibitor contamination-related problems in military aircraft hydraulic systems SO HYDRAULIC FAILURE ANALYSIS: FLUIDS, COMPONENTS, AND SYSTEM EFFECTS SE AMERICAN SOCIETY FOR TESTING AND MATERIALS SPECIAL TECHNICAL PUBLICATION LA English DT Proceedings Paper CT Symposium on Hydraulic Failure Analysis - Fluids, Components, and System Effects CY DEC 05-06, 1999 CL RENO, NV SP Amer Soc Testing & Mat, Comm D2 DE hydraulic components; hydraulic fluids; barium dinonylnaphthalene sulfonate; stuck servovalve; infrared spectroscopy AB Stuck servovalves were observed during pre-flight checks in some aircraft using MIL-PRF-83282 hydraulic fluid. Analysis of hydraulic fluid samples and stuck valves as described in the paper provided a link between valve failures and barium dinonylnaphthalene sulfonate (BSN) content of the hydraulic fluid. The BSN contamination was traced to residual MIL-PRF-6083 preservative fluid that had not been drained from components before installation on the aircraft. The hypothesis was validated by laboratory tribological experiments using a reciprocating tribometer and grazing angle microscope Fourier transform infrared spectroscopy. Corrective actions included reemphasizing procedures to drain MIL-PRF-6083 from components and establishing a 10 ppm maximum limit for barium in new MIL-PRF-83282. Since the corrective actions were taken, no valves have locked up, further validation that the preservative fluid, MIL-PRF-6083, as a contaminant in the operational aircraft, is the root cause of the valve lockups. The recommended corrective actions were: 1) removing and cleaning the hydraulic valves; 2) assuring that the barium content of the aircraft hydraulic fluid does not exceed 15 ppm. Other factors besides the presence of BSN which contributed to the valve-sticking problem included: the elevated hydraulic fluid temperature, the valve design and materials, and the duty cycle. The simplest and most cost-effective solution to the problem was limiting the amount of BSN in the aircraft hydraulic system. Other aircraft hydraulic systems problems perceived to be caused by BSN contamination are discussed. C1 USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. RP Sharma, SK (reprint author), USAF, Res Lab, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN SOCIETY TESTING AND MATERIALS PI W CONSHOHOCKEN PA 100 BARR HARBOR DRIVE, W CONSHOHOCKEN, PA 19428-2959 USA SN 1040-1695 BN 0-8031-2883-5 J9 AM SOC TEST MATER PY 2001 VL 1339 BP 489 EP 499 DI 10.1520/STP38297S PG 11 WC Engineering, Mechanical; Materials Science, Characterization & Testing SC Engineering; Materials Science GA BS17Q UT WOS:000168981000035 ER PT B AU Gluck, K Allard, T Allender, L Chipman, S Glinert, E Tangney, J Warren, R AF Gluck, K Allard, T Allender, L Chipman, S Glinert, E Tangney, J Warren, R BE Altmann, EM Cleeremans, A Schunn, CD Gray, WD TI Panel on government interests and opportunities in cognitive modeling SO ICCM - 2001: PROCEEDINGS OF THE 2001 FOURTH INTERNATIONAL CONFERENCE ON COGNITIVE MODELING LA English DT Proceedings Paper CT 4th International Conference on Cognitive Modeling CY JUL 26-28, 2001 CL GEORGE MASON UNIV, FAIRFAX, VA SP USN Off Res, Natl Sci Fdn, USAF Res Lab Human Effectiveness Directorate, CHI Syst, BBN Technologies HO GEORGE MASON UNIV C1 USAF, Res Lab, Warfighter Training Res Div, Washington, DC USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LAWRENCE ERLBAUM ASSOC PUBL PI MAHWAH PA 10 INDUSTRIAL AVE, MAHWAH, NJ 07430 USA BN 0-8058-4042-7 PY 2001 BP 33 EP 33 PG 1 WC Computer Science, Artificial Intelligence; Psychology, Developmental SC Computer Science; Psychology GA BS64T UT WOS:000170688900004 ER PT J AU Harrison, P Soref, RA AF Harrison, P Soref, RA TI Population-inversion and gain estimates for a semiconductor TASER SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE far-infrared; intersubband; quantum cascade lasers; Stark-ladder; superlattice; terahertz ID QUANTUM CASCADE LASERS; INTERSUBBAND TRANSITIONS; STARK LADDERS; MU-M; INTERWELL; EMISSION; WELLS AB We have investigated a solid-state design advanced (see Soref et al, in SPIE Proceedings, vol. 3795, p, 516, 1999) to achieve a terahertz-amplification-by-the-stimulated-emision-of-radiation (TASER), The original design was based on light-to heavy-hole intersubband transitions in SiGe/Si heterostructures, This work adapts the design to electron intersubband transitions in the more readily available GaAs/Ga1-xAlxAs material system. It is found that the electric-field induced anti-crossings of the states, derived from the first excited state with the ground states of a superlattice in the Stark-ladder regime, offers the possibility of a population inversion and gain at room temperature. C1 Univ Leeds, Sch Elect & Elect Engn, Inst Microwave & Photon, Leeds LS2 9JT, W Yorkshire, England. USAF, Res Lab, SNHC, Hanscom AFB, MA 01731 USA. RP Harrison, P (reprint author), Univ Leeds, Sch Elect & Elect Engn, Inst Microwave & Photon, Leeds LS2 9JT, W Yorkshire, England. NR 18 TC 19 Z9 19 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 2001 VL 37 IS 1 BP 153 EP 158 DI 10.1109/3.892737 PG 6 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 390UW UT WOS:000166316300020 ER PT J AU Sarkar, TK Wang, H Park, S Adve, R Koh, J Kim, K Zhang, YH Wicks, MC Brown, RD AF Sarkar, TK Wang, H Park, S Adve, R Koh, J Kim, K Zhang, YH Wicks, MC Brown, RD TI A deterministic least-squares approach to space-time adaptive processing (STAP) SO IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION LA English DT Article DE atmospheric interference; D-3 approach; object detection; radar clutter; space-time adaptive processing (STAP) ID ANTENNAS AB A direct data domain (D-3) least-squares space-time adaptive processing (STAP) approach is presented for adaptively enhancing signals in a nonhomogeneous environment. The nonhomogeneous environment may consist of nonstationary clutter and could include blinking jammers. The D-3 approach is applied to data collected by an antenna array utilizing space and in time (Doppler) diversity. Conventional STAP generally utilizes statistical methodologies based on estimating a covariance matrix of the interference using data from secondary range cells. As the results are derived from ensemble averages, one filter (optimum in a probabilistic sense) is obtained for the operational environment, assumed to be wide sense stationary. However, for highly transient and inhomogeneous environments the conventional statistical methodology is difficult to apply Hence, the D-3 method is presented as it analyzes the data in space and time over each range cell separately. The D-3 method is deterministic in approach. From an operational standpoint, an optimum method could be a combination of these two diverse methodologies. This paper represents several new D-3 approaches. One is based on the computation of a generalized eigenvalue for the signal strength and the others are based on the solution of a set of block Hankel matrix equations. Since the matrix of the system of equations to be solved has a block Hankel structure, the conjugate gradient method and the fast Fourier transform (FFT) can be utilized for efficient solution of the adaptive problem. illustrative examples presented in this paper use measured data from the multichannel airborne radar measurements (MCARM) database to detect a Sabreliner in the presence of urban, land, and sea clutter. An added advantage for the D-3 method in solving real-life problems is that simultaneously many realizations can be obtained for the same solution for the signal of interest (SOI), The degree of variability amongst the different results can provide a confidence level of the processed results. The D-3 method may also be used for mobile communications. C1 Syracuse Univ, Dept Elect Engn & Comp Sci, Syracuse, NY 13244 USA. USAF, Res Lab, Sensors Directorate, Griffiss AFB, NY 13441 USA. RP Sarkar, TK (reprint author), Syracuse Univ, Dept Elect Engn & Comp Sci, Syracuse, NY 13244 USA. NR 17 TC 68 Z9 93 U1 1 U2 12 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 2001 VL 49 IS 1 BP 91 EP 103 PG 13 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA 411GX UT WOS:000167490700012 ER PT B AU Bradley, CJ Collins, PJ Terzuoli, AJ Temple, MA Wilson, KS Fortuny, J Lewis, G AF Bradley, CJ Collins, PJ Terzuoli, AJ Temple, MA Wilson, KS Fortuny, J Lewis, G GP IEEE IEEE TI A performance analysis of several bistatic calibration techniques SO IGARSS 2001: SCANNING THE PRESENT AND RESOLVING THE FUTURE, VOLS 1-7, PROCEEDINGS SE IEEE International Symposium on Geoscience and Remote Sensing (IGARSS) LA English DT Proceedings Paper CT IEEE International Geoscience and Remote Sensing Symposium CY JUL 09-13, 2001 CL UNIV NEW S WALES, SYDNEY, AUSTRALIA SP IEEE, IEEE, Geosci & Remote Sensing Soc, NASA, US Dept Commerce, Natl Ocean & Atmosphere Adm, CSA ASC, Off Naval Res, RSPAA, URSI HO UNIV NEW S WALES AB Several popular bistatic calibration techniques are evaluated, and comparisons are made between the relative merits of various calibration objects. This analysis considers the following: sensitivity to object alignment error, sensitivity to polarization impurity, and ease of implementation. Both theoretical concepts and practical considerations are discussed, based on measurements accomplished at the European Microwave Signature Laboratory (EMSL) of the Joint Research Centre (JRC) in Ispra, Italy. This facility has the capability to produce far-field, fully polarimetric, bistatic measurements with an approximately 30 cm diameter quiet zone, with the necessary precision for comparing different calibration methods. C1 USAF, Inst Technol, Dayton, OH 45401 USA. RP Bradley, CJ (reprint author), USAF, Inst Technol, POB 3402, Dayton, OH 45401 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU IEEE PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA BN 0-7803-7031-7 J9 INT GEOSCI REMOTE SE PY 2001 BP 2572 EP 2574 PG 3 WC Engineering, Electrical & Electronic; Geosciences, Multidisciplinary; Remote Sensing SC Engineering; Geology; Remote Sensing GA BU88J UT WOS:000177297200827 ER PT S AU Silverman, J Caefer, CE Mooney, JM Weeks, MM Yip, P AF Silverman, J Caefer, CE Mooney, JM Weeks, MM Yip, P BE Descour, MR Shen, SS TI Automated clustering/segmentation of hyperspectral images based on histogram thresholding SO IMAGING SPECTROMETRY VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry VII CY AUG 01-03, 2001 CL SAN DIEGO, CA SP SPIE DE hyperspectral data; clustering; segmentation; histograms; thresholds; unsupervised classification AB A very simple and fast technique for clustering/segmenting hyperspectral images is described. The technique is based on the histogram of "divergence images": namely, single image reductions of the hyperspectral data cube whose values reflect spectral differences. Multi-value thresholds are set from the local extrema of such a histogram. Two methods are identified for combining the information of a pair of divergence images: a dual method of combining thresholds generated from 1D histograms; and a true 2D histogram method. These histogram-based segmentations have a built-in fine to coarse clustering depending on the extent of smoothing of the histogram before determining the extrema. The technique is useful at the fine scale as a powerful single image display "summary" of a data cube or at the coarser scales as a quick unsupervised classification or a good starting point for an operator-controlled supervised classification. Results will be shown for visible, SWIR, and MWIR hyperspectral imagery. C1 USAF, Res Lab, AFRL SNHI, Hanscom AFB, MA 01731 USA. RP Silverman, J (reprint author), USAF, Res Lab, AFRL SNHI, 80 Scott Rd, Hanscom AFB, MA 01731 USA. NR 7 TC 1 Z9 1 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 0-8194-4194-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4480 BP 65 EP 75 PG 11 WC Engineering, Aerospace; Remote Sensing; Imaging Science & Photographic Technology; Spectroscopy SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Spectroscopy GA BU15D UT WOS:000175162000008 ER PT S AU Yarbrough, S Caudill, T Kouba, E Osweiler, V Arnold, J Quarles, R Russell, J AF Yarbrough, S Caudill, T Kouba, E Osweiler, V Arnold, J Quarles, R Russell, J BE Descour, MR Shen, SS TI MightySat II.1 hyperspectral imager: summary of on-orbit performance SO IMAGING SPECTROMETRY VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry VII CY AUG 01-03, 2001 CL SAN DIEGO, CA SP SPIE DE hyperspectral imager; space based imager AB The primary payload on a small-satellite, the Air Force Research Laboratory's MightySat II.1, is a spatially modulated Fourier Transform Hyperspectral Imager (FTHSI) designed for terrain classification. The heart of this instrument is a solid block Sagnac interferometer with 85cm(-1) spectral resolution over the 475nm to 1050nm wavelength range and 30m spatial resolution. Coupled with this hyperspectral imager is a Quad-C40 card, used for on-orbit processing. The satellite was launched on 19 July 2000 into a 575km, 97.8 degree inclination, sun-synchronous orbit. The hyperspectral imager collected its first data set on 1 August 2000. To the best of our knowledge, the MightySat II.1 sensor is the first true hyperspectral earth-viewing imager to be successfully operated in space. The paper will describe the satellite and instrument, pre-launch calibration results, on-orbit performance, and the calibration process used to characterize the sensor. We will also present data on the projected lifetime of the sensor along with samples of the types of data being collected. C1 USAF, Res Lab VSSS, Kirtland AFB, NM 87117 USA. RP Yarbrough, S (reprint author), USAF, Res Lab VSSS, Kirtland AFB, NM 87117 USA. NR 6 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 0-8194-4194-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4480 BP 186 EP 197 PG 12 WC Engineering, Aerospace; Remote Sensing; Imaging Science & Photographic Technology; Spectroscopy SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Spectroscopy GA BU15D UT WOS:000175162000020 ER PT S AU LeVan, PD Maestas, D AF LeVan, PD Maestas, D BE Descour, MR Shen, SS TI Multi-octave spectral imaging in the infrared - a newly emerging approach SO IMAGING SPECTROMETRY VII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Imaging Spectrometry VII CY AUG 01-03, 2001 CL SAN DIEGO, CA SP SPIE DE spectral imaging; infrared; focal plane array; electro-optics AB A new approach is described for obtaining spectral imagery over a broad range of infrared wavelengths, with high efficiency, and with a single grating element and focal plane array. The approach represents a simplification and mass reduction over the traditional approach involving multiple focal plane arrays, dispersing elements, and optical beamsplitters. The new approach has significant advantages for space-based hyperspectral imagers operating in the infrared over a broad range of wavelengths (e.g., MWIR & LWIR), where the reduction in cryo-cooled mass relative to the multi-channel approach translates into noteworthy savings in cryo-cooling requirements and launch costs. Overlapping grating orders are focused onto a multi-waveband focal plane array in order to create spectral images of a scene simultaneously in multiple wavelength regions. The blaze of the grating is chosen so that all spectral orders are dispersed with high grating efficiency. Such an approach extends the spectral range of dispersive spectrometers to several octaves of wavelength, while preserving the compact packaging and cryogenic requirements of conventional (one octave) instruments. We conclude with a description of a ground-based demonstration of a dual-octave embodiment of the concept. C1 USAF, Res Lab, Kirtland AFB, NM 87117 USA. RP LeVan, PD (reprint author), USAF, Res Lab, Kirtland AFB, NM 87117 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 0-8194-4194-5 J9 P SOC PHOTO-OPT INS PY 2001 VL 4480 BP 388 EP 394 PG 7 WC Engineering, Aerospace; Remote Sensing; Imaging Science & Photographic Technology; Spectroscopy SC Engineering; Remote Sensing; Imaging Science & Photographic Technology; Spectroscopy GA BU15D UT WOS:000175162000042 ER PT S AU Skormin, VA Delgado-Frias, JG McGee, DL Giordano, JV Popyack, LJ Gorodetski, VI Tarakanov, AO AF Skormin, VA Delgado-Frias, JG McGee, DL Giordano, JV Popyack, LJ Gorodetski, VI Tarakanov, AO BE Gorodetski, VI Popyack, LJ Skormin, VA TI BASIS: A biological approach to system information security SO INFORMATION ASSURANCE IN COMPUTER NETWORKS: METHODS, MODELS AND ARCHITECTURES FOR NETWORK SECURITY, PROCEEDINGS SE LECTURE NOTES IN COMPUTER SCIENCE LA English DT Article; Proceedings Paper CT International Workshop on Mathematical Methods, and Architectures for Network Security Systems (MMM-ACNS 2001) CY MAY 21-23, 2001 CL ST PETERSBURG, RUSSIA SP Russian Acad Sci, St Petersburg Inst Informat & Automat AB Advanced information security systems (ISS) play an ever-increasing role in the information assurance in global computer networks. Dependability of ISS is being achieved by the enormous amount of data processing that adversely affects the overall network performance. Modem ISS architecture is viewed as a multi-agent system comprising a number of semi-autonomous software a gents designated to prevent particular kinds of threats and suppress specific types of attacks without burdening the network. The high efficiency of such a system is achieved by establishing the principles of successful individual and cooperative operation of particular agents. Such principles, evolved during evolution, are known to be implemented in biological immune systems. The aim of this paper is the exploration of the basic principles that govern an immune system and the potential implementation of these principles in a multiagent ISS of a heterogeneous computer network. C1 SUNY Binghamton, Binghamton, NY 13902 USA. USAF, Res Lab, Rome, NY USA. St Petersburg Inst Informat & Automat, St Petersburg, Russia. RP Skormin, VA (reprint author), SUNY Binghamton, Binghamton, NY 13902 USA. EM vskormin@binghamton.edu; delgado@binghamton.edu; mcgee@binghamton.edu; Leonard.Popyack@rl.af.mil; gor@mail.iias.spb.su; tar@mail.iias.spb.su; tar@mail.iias.spb.su; gor@mail.iias.spb.su; vskormin@binghamton.edu NR 10 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER-VERLAG BERLIN PI BERLIN PA HEIDELBERGER PLATZ 3, D-14197 BERLIN, GERMANY SN 0302-9743 BN 3-540-42103-3 J9 LECT NOTES COMPUT SC PY 2001 VL 2052 BP 127 EP 142 PG 16 WC Computer Science, Theory & Methods SC Computer Science GA BY43H UT WOS:000189224600015 ER PT S AU McManamon, PF Watson, EA AF McManamon, PF Watson, EA BE Andresen, BF Fulop, GF Strojnik, M TI Nonmechanical beam steering for passive sensors SO INFRARED TECHNOLOGY AND APPLICATIONS XXVII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Infrared Technology and Applications XXVII Conference CY APR 16-20, 2001 CL ORLANDO, FL SP SPIE AB By using resets of multiple wavelengths to limit dispersion, we show conceptually that we will be able to steer passive, broadband, electro-optical sensors over wide angles using optical phased array technology. The dispersion associated with optical phased array beam steering can be limited to values of 20 to 80 times the diffraction limit I for very large angle beam steering. Much of the remaining factor of 20 - 80 may be correctable using digital techniques. A significant obstacle associated with widespread implementation of optical phased array beam steering is wavelength dispersion associated with resets.(2) We discuss optical phased array beam steering using resets of greater than one wavelength. By using larger resets the unfolded phase front for wavelengths other than the design wavelength can be maintained closer to a prism, thus limiting dispersion. This technique can be implemented with the variable period beam steering approach or the variable blaze beam steering approach. One way to implement the variable blaze beam steering approach is using moveable lenslets.(3) This method of implementation is amenable to large value resets, so it is an attractive method of implementation for this multiple wavelength reset, limited dispersion, beam steering technique. C1 USAF, Res Lab, Washington, DC USA. RP McManamon, PF (reprint author), 2224 Avion Circle, Wright Patterson AFB, OH 45433 USA. NR 6 TC 5 Z9 5 U1 0 U2 0 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4064-7 J9 P SOC PHOTO-OPT INS PY 2001 VL 4369 BP 140 EP 148 DI 10.1117/12.445284 PG 9 WC Engineering, Electrical & Electronic; Optics SC Engineering; Optics GA BT65A UT WOS:000173642200014 ER PT S AU Agee, FJ Gaudet, JA Prather, WD AF Agee, FJ Gaudet, JA Prather, WD BE Brandt, HE TI Focus on current topics in Air Force high power microwave (HPM) research SO INTENSE MICROWAVE PULSES VIII SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT Conference on Intense Microwave Pulses VIII CY APR 17-18, 2001 CL ORLANDO, FL SP SPIE DE high power microwaves; ultra-wideband sources; Impulse Radiating Antennas; RF effects; RF breakdown AB This paper describes current projects in High Power Microwave (HPM) source development within the Air Force's basic research program managed by the Air Force Office of Scientific Research and conducted at the Air Force Research Laboratory's Directed Energy Directorate and at universities throughout the U.S. and the world. Studies are proceeding along two separate paths: narrow band high power microwave tubes and ultra-wide band sources. While these two paths invoke drastically different physical mechanisms that produce microwave radiation qualitatively distinct from each other, there are many common technical challenges. The focus of this report will be the active research in the Air Force ultra-wide band program, but many of the technical improvements being sought for improved materials, high voltage breakdown mitigation, and advanced design techniques will help the entire high power microwave program. The paper concludes with a brief discussion of the future of HPM research. C1 USAF, Off Sci Res, AFOSR NE, Arlington, VA 22203 USA. RP Agee, FJ (reprint author), USAF, Off Sci Res, AFOSR NE, Arlington, VA 22203 USA. NR 26 TC 0 Z9 0 U1 0 U2 1 PU SPIE-INT SOC OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA SN 0277-786X BN 0-8194-4066-3 J9 P SOC PHOTO-OPT INS PY 2001 VL 4371 BP 1 EP 10 DI 10.1117/12.436921 PG 10 WC Optics SC Optics GA BT28P UT WOS:000172533900001 ER PT S AU Szmulowicz, F Brown, GJ Liu, HC Shen, A Wasilewski, ZR Buchanan, M AF Szmulowicz, F Brown, GJ Liu, HC Shen, A Wasilewski, ZR Buchanan, M BE Rutkowski, J Wenus, J Kubiak, L TI GaAs/AlGaAs p-type multiple-quantum wells for infrared detection at normal incidence: model and experiment SO INTERNATIONAL CONFERENCE ON SOLID STATE CRYSTALS 2000: EPILAYERS AND HETEROSTRUCTURES IN OPTOELECTRONICS AND SEMICONDUCTOR TECHNOLOGY SE PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) LA English DT Proceedings Paper CT 2nd International Conference on Solid State Crystals 2000 (ICSSC 2000) CY OCT 09-13, 2000 CL ZAKOPANE, POLAND SP Military Univ Technol, Inst Appl Phys, Polish Soc Crystal Growth, SPIE, State Comm Sci Res, European Off Aerosp Res & Dev, Tech Univ Lodz, Inst Phys, Wroclaw Univ Technol, Inst Phys DE infrared detector; band-gap engineering; GaAs/AlGaAs; p-type ID ENVELOPE-FUNCTION APPROXIMATION; LIGHT-EMITTING DIODE; PHOTORESPONSE MEASUREMENT; GENERAL EXPRESSION; PHOTODETECTOR; ABSORPTION; SUPERLATTICES; TRANSITIONS; BAND AB The development of devices for mid-, long-, and very long-wavelength IR detection has benefited greatly from advances in band-gap engineering. Recently, there has been great progress in the development of n-type GaAs/AlGaAs quantum well infrared photoconductor (QWIP) detector arrays in all three technologically important wavelength windows. p-type GaAs/AlGaAs QWIPs represent a viable alternative to n-type GaAs/AlGaAs QWIPs, offering the advantage of normal incidence absorption without the need for grating couplers. The maturity of the MBE of GaAs/AlGaAs layered materials offers the possibility of mass producing low cost, high performance, large size, high uniformity, multicolor, high frequency bandwidth, two-dimensional imaging QWIP arrays. This paper describes progress in optimizing the performance of p-type GaAs/AlGaAs QWIPs through modeling, growth, acid characterization. Using the 8x8 envelope-function approximation (EFA), a number of structures were designed and their optical absorption calculated for comparison with experiment. Samples were grown by MBE based on the theoretical designs and their photoresponse measured. p-type QWIPs were optimized with respect to the well and barrier widths, alloy concentration, and dopant concentration; resonant cavity devices were also fabricated and temperature dependent photoresponse was measured. The quantum efficiencies and the background-limited (BLIP) detectivities under BLIP conditions of our p-QWIPs are comparable to those of n-QWIPs; however, the responsivities are smaller. For our mid-IR p-QWIPs, the 2D doping densities of 1-2x10(12) cm(-2) maximized the BLIP temperature and dark current limited detectivity by operating at around 100 K. At 80 K, the detectivity of the optimum doped sample was 3.5x10(11) cmHz(1/2)/W at 10V bias. Barrier widths greater than 200 Angstrom were sufficient to impede the tunneling dark current; resonant cavities enhanced absorption fivefold. 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 36 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 0-8194-4116-3 J9 P SOC PHOTO-OPT INS PY 2001 VL 4413 BP 293 EP 306 DI 10.1117/12.425449 PG 14 WC Crystallography; Engineering, Electrical & Electronic; Optics; Physics, Applied SC Crystallography; Engineering; Optics; Physics GA BS29E UT WOS:000169369400053 ER PT J AU Cioffi-Revilla, C Lai, D AF Cioffi-Revilla, C Lai, D TI Chinese warfare and politics in the ancient East Asian international system, ca, 2700 BC to 722 BC SO INTERNATIONAL INTERACTIONS LA English DT Article DE war; data sets; time-series; codebook; ancient China; Asia ID WAR; ORIGINS AB Ancient East Asia is the second oldest "protobellic area" and pristine slate system of international relations within the global international system, after West Asia (ancient Near East). In a previous study Cioffi-Revilla and Lai (1995) reported the first findings on the origins and evolution of war and politics in ancient China (Legendary, Xia [Hsia], Shang, and Western Zhou [Chou] periods), ca. 2700 B.C. to 722 B.C. In this paper we make public an expanded data set (N = 104 cases, 12 variables; version 2.0), explaining our sources, measurements, and data quality control procedures. The new data set will permit investigators to test hypotheses about warfare distributions, ethnic and protracted conflicts, time series, periodicity, system dynamics, and structural relationships (e.g., war-polarity theories). This new long-range data set should also promote a new stage in comparative analyses of the universal and particular properties of warfare and international systems, both cross-polity and longitudinally. C1 Univ Colorado, Dept Polit Sci, Boulder, CO 80309 USA. US Air War Coll, Dept Int Secur Studies, Maxwell AFB, AL 36112 USA. RP Cioffi-Revilla, C (reprint author), Univ Colorado, Dept Polit Sci, Boulder, CO 80309 USA. NR 44 TC 3 Z9 3 U1 0 U2 4 PU GORDON BREACH PUBLISHING, TAYLOR & FRANCIS GROUP PI PHILADELPHIA PA 325 CHESTNUT ST, 8TH FL, PHILADELPHIA, PA 19106 USA SN 0305-0629 J9 INT INTERACT JI Int. Interact. PY 2001 VL 26 IS 4 BP 347 EP 378 DI 10.1080/03050620108434971 PG 32 WC International Relations SC International Relations GA 430FK UT WOS:000168563700001 ER PT J AU Haas, MW Hettinger, LJ AF Haas, MW Hettinger, LJ TI Current research in adaptive interfaces - Preface SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Editorial Material C1 USAF, HECP, Res Lab, Wright Patterson AFB, OH 45433 USA. Logicon Tech Serv Inc, Dayton, OH USA. RP Haas, MW (reprint author), USAF, HECP, Res Lab, 2255 H St,Bldg 248,Area B, Wright Patterson AFB, OH 45433 USA. NR 4 TC 5 Z9 5 U1 0 U2 0 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 2001 VL 11 IS 2 BP 119 EP 121 DI 10.1207/S15327108IJAP1102_01 PG 3 WC Psychology, Applied SC Psychology GA 453KG UT WOS:000169914600001 ER PT J AU Bennett, KB Cress, JD Hettinger, LJ Stautberg, D Haas, MW AF Bennett, KB Cress, JD Hettinger, LJ Stautberg, D Haas, MW TI A theoretical analysis and preliminary investigation of dynamically adaptive interfaces SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article ID DISPLAYS AB A dynamically adaptive interface (DAI) is a computer interface that changes the display or control characteristics of a system (or both) in real time. The goal of DAIs is to anticipate informational needs or desires of the user and provide that information without the requirement of an explicit control input by the user. DAIs have the potential to improve overall human-machine system performance if properly designed; they also have a very real potential to degrade performance if they are not properly designed. This article explores both theoretical and practical issues in the design of DAIs. The relation of the DAI concept to decision aiding and automation is discussed, and a theoretical framework for design is outlined. A preliminary investigation of the DAI design concept was conducted in the domain of aviation (precision, low-level navigation). Nontraditional controls (a force reflecting stick) and displays (a configural flight director) were developed to support performance at the task. A standard interface (conventional controls and displays), a candidate interface (alternative controls and displays), and an adaptive interface (dynamically alternating between the standard and candidate displays) were evaluated. The results indicate that significant performance advantages in the quality of route navigation were obtained with the candidate and adaptive interfaces relative to the standard interface; no significant differences between the candidate and adaptive interfaces were obtained. The implications of these results are discussed, with special emphasis on their relation to fundamental challenges that must be met for the DAI concept to be a viable design alternative. C1 Wright State Univ, Dept Psychol, Dayton, OH 45435 USA. Logicon Tech Serv Inc, Dayton, OH USA. USAF, Res Lab, Human Effectiveness Directorate, Wright Patterson AFB, OH 45433 USA. RP Bennett, KB (reprint author), Wright State Univ, Dept Psychol, 3640 Colonel Glenn Hwy, Dayton, OH 45435 USA. EM kevin.bennett@wright.edu NR 29 TC 6 Z9 6 U1 4 U2 4 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1050-8414 J9 INT J AVIAT PSYCHOL JI Int. J. Aviat. Psychol. PY 2001 VL 11 IS 2 BP 169 EP 195 DI 10.1207/S15327108IJAP1102_04 PG 27 WC Psychology, Applied SC Psychology GA 453KG UT WOS:000169914600004 ER PT J AU Haas, MW Nelson, WT Repperger, D Bolia, R Zacharias, G AF Haas, MW Nelson, WT Repperger, D Bolia, R Zacharias, G TI Applying adaptive control and display characteristics to future air force crew stations SO INTERNATIONAL JOURNAL OF AVIATION PSYCHOLOGY LA English DT Article ID AIDED VISUAL-SEARCH; WORKLOAD AB The Human Effectiveness Directorate of the Air Force Research Laboratory is developing and evaluating human-machine interface concepts to enhance overall weapon system performance by embedding knowledge of the operator's state inside the interface, enabling the interface to make informed, automated decisions regarding many of the interface's information management display characteristics. Some of these characteristics include information modality, spatial arrangement, and temporal organization. By increasing the ability of the interface to respond, or adapt, to the changing requirements of the human operator in real time-in essence closing the loop-the interface provides intuitive information management to the operator and provides real-time human engineering. C1 USAF, Res Lab, Wright Patterson AFB, OH 45433 USA. Divine Whittman Hart, Cincinnati, OH USA. Charles River Analyt, Cambridge, MA USA. RP Haas, MW (reprint author), USAF, Res Lab, 2255 H St,Bldg 248,Area B, Wright Patterson AFB, OH 45433 USA. NR 25 TC 4 Z9 4 U1 0 U2 0 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 2001 VL 11 IS 2 BP 223 EP 235 DI 10.1207/S15327108IJAP1102_06 PG 13 WC Psychology, Applied SC Psychology GA 453KG UT WOS:000169914600006 ER PT J AU Gordnier, RE Melville, RB AF Gordnier, RE Melville, RB TI Numerical simulation of limit-cycle oscillations of a cropped delta wing using the full Navier-Stokes equations SO INTERNATIONAL JOURNAL OF COMPUTATIONAL FLUID DYNAMICS LA English DT Article DE limit cycle oscillation; computational aeroelasticity; delta wing; fluid/structure interaction ID VORTEX BREAKDOWN; ONSET; FLOW AB This paper presents simulations of limit-cycle oscillations of a cropped delta wing using a computational technique that implicitly couples a full Navier-Stokes solver to a linear structural solver. Computational results are compared with existing experimental measurements of the limit-cycle response of the delta wing. The limit-cycle oscillation is shown to consist primarily of a response of the first bending mode and the first torsional mode. Aerodynamic features of the limit cycle identified include a leading-edge vortex and a double shock structure. The leading edge vortex acts like an aerodynamic spring and provides the physical mechanism for the evolution of the limit cycle on the delta wing. Computations are repeated using the Euler equations to determine if the inviscid flow equations adequately simulate the observed limit cycle response. C1 USAF, Res Lab, VAAC, Ctr Excellence Computat Simulat, Wright Patterson AFB, OH 45433 USA. RP Gordnier, RE (reprint author), USAF, Res Lab, VAAC, Ctr Excellence Computat Simulat, Bldg 146,Rm 225,2210 8th St, Wright Patterson AFB, OH 45433 USA. NR 26 TC 15 Z9 16 U1 1 U2 2 PU GORDON BREACH PUBLISHING, TAYLOR & FRANCIS GROUP PI PHILADELPHIA PA 325 CHESTNUT ST, 8TH FL, PHILADELPHIA, PA 19106 USA SN 1061-8562 J9 INT J COMPUT FLUID D JI Int. J. Comput. Fluid Dyn. PY 2001 VL 14 IS 3 BP 211 EP 224 DI 10.1080/10618560108940725 PG 14 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 458WT UT WOS:000170219000003 ER EF