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20050173297 Air Force Research Lab., Wright-Patterson AFB, OH USA Performance of a Low-Density Hypersonic Magneto-Aerodynamic Facility Kimmel, R.; Hayes, J.; Tyler, C.; Shang, J. S.; Oct. 2003; 21 pp.; In English; Original contains color illustrations Report No.(s): AD-A432574; No Copyright; Avail: Defense Technical Information Center (DTIC) A hypersonic, weakly ionized gas experimental facility has been successfully developed for magnetoaerodynamics basic research. The weakly ionized air is generated by a combination of direct current discharge, radio frequency discharge, and a combination of both in a blow-down, open jet, Mach 5 flow channel. The plasma field is characterized by electron temperatures around 10,000 K, and electron number density up to 2x10(exp 12) cu cm. The magnetic field is provided by a steady sate solenoid that can generate a maximum field up to three Tesla and an array of permanent magnets. In this environment, the maximum ma magneto-aerodynamic interaction parameter per unit length is around 1.5 per meter. A collection of plasma diagnostic tools including emission spectroscopy, microwave absorption, and Langmuir probes also are available. DTIC Hypersonics; Magnetohydrodynamics 20050173442 Naval Postgraduate School, Monterey, CA USA Interdicting a Force Deployment: Two-Sided Optimization of Asset Selection, Lift Scheduling, and Multi-Commodity Load Planning Koprowski, Peter M.; Mar. 2005; 76 pp.; In English; Original contains color illustrations Report No.(s): AD-A432887; No Copyright; Avail: Defense Technical Information Center (DTIC) A military deployment is visible and vulnerable. But, deployments are currently planned assuming they can be completed with surprise, or defended from any threat. JFAST, the current deployment planning and visualization tool of choice, uses heuristics of unknown reliability that yield deployment plans of unknown quality, and ignores vulnerability. We introduce LIFTER, an integer-linear program (ILP) that optimizes a time-phased force deployment (TPFDD) by day, by asset cycle, and by TPFDD line (individual shipment from an origin to a destination), and ATTACKER, also an ILP, representing a smart enemy’s resource-limited interdictions to maximally disrupt LIFTER’s subsequently re-optimized TPFDD plan. LIFTER activates transport assets from an allocation list, and yields a complete logistic plan that minimizes disruption represented by penalties for early, tardy, late, or dropped shipments, and for under-utilization of asset capacity. We use LIFTER to qualitatively assess JFAST heuristic plans. We also link both ILPs in a decomposition-based search for the best deployment plan around the worst-case interdiction, given that the actions of deployer and interdictor are transparent to both parties. We explain how JFAST could be embellished with its own version of ATTACKER. A key discovery here is a gauge of the value of intelligence, deception, and secrecy. DTIC Commodities; Lift; Loads (Forces); Logistics; Optimization; Scheduling 20050173448 Air Force Research Lab., Hanscom AFB, MA USA Modified-Dewan Optical Turbulence Parameterizations Jackson, Artie; Jun. 2004; 72 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): Proj-1010 Report No.(s): AD-A432901; AFRL-VS-HA-TR-2004-1116; No Copyright; Avail: Defense Technical Information Center (DTIC) The Dewan optical turbulence parameterization has been the Air Force Research Laboratory optical turbulence model of choice for various research efforts involving optical turbulence during the past several years. The Dewan parameterization was developed to convert standard radiosonde data into vertical profiles of Cr2, the refractive index structure constant, which is the critical parameter for describing optical turbulence. The Dewan parameterization provides useful vertical profiles of Cr2 in the upper troposphere and stratosphere, though there is certainly a need for improvement at these altitudes. The statistical relationships relating Dewan’s Y parameter to wind shear, which form the basis of the Dewan parameterization, are often not found in atmospheric measurement data, thus this is an area to explore in developing improved optical turbulence parameterization for the troposphere and stratosphere. Several modified-Dewan optical turbulence parameterization are developed and tested for the lower troposphere, the troposphere, the stratosphere and the combined tropospherelstratosphere. DTIC Optical Equipment; Parameterization; Turbulence 115 20050173450 Army Research Lab., Aberdeen Proving Ground, MD USA Coupling of CFD and CSM Codes for the Study of Projectile Response to Ballistics Environment Ray, Stephen E.; Newill, James F.; Nusca, Michael J.; Horst, Albert W.; Dec. 2004; 3 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): DAAD19-03-D-0001 Report No.(s): AD-A432903; No Copyright; Avail: Defense Technical Information Center (DTIC) The state-of-the-art interior ballistics (IB) code for the Army, ARL-NGEN3, is being used to predict the interior ballistics behavior of next-generation gun charges, which include densely-packed solid propellants. Recently, the results from ARL-NGEN3 code simulations were linked to structural dynamics codes in order to predict the in-bore behavior of the projectile afterbody. In the current paper results are presented from recent efforts to bring together the capabilities of ARL-NGEN3 and two of the prominent structural mechanics codes, DYNA3D and EPIC. Results from simulations of a test case show the effectiveness of this approach. DTIC Ballistics; Coding; Command Service Modules; Computational Fluid Dynamics; Interior Ballistics; Projectiles; Structural Analysis 20050173477 Wisconsin Univ., Madison, WI USA An Advanced Platform for Biomolecular Detection and Analysis Systems Beebe, David J.; Feb. 2005; 149 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): F30602-00-2-0570; DARPA ORDER-E117; Proj-E117 Report No.(s): AD-A432950; AFRL-IF-RS-TR-2005-54; No Copyright; Avail: Defense Technical Information Center (DTIC) A comprehensive new approach to the rapid and flexible construction of microfluidic-based systems for biological and chemical (BC) agent detection has been demonstrated. The foundation of the approach is a new manufacturing process called MicroFluidic Tectonics that combines responsive hydrogel materials with novel liquid phase Microfluidic construction methods. The approach addresses several critical issues relevant to BC agent defense - simple device fabrication, just-in-time manufacturing, integration of all system functions through ‘in situ’ fabrication, simple operation, self-regulation of on chip flow, no electrical power, rapid and highly adaptable to changing needs. MicroFluidic Tectonics (microFT) processes capable of manufacturing elegant (operationally simple, but functionally complex) microfluidic systems in the field were developed. In addition, methods for the creation of novel BC sensing systems that directly couple micro scale detection to macro scale alerts were shown. The systems are capable of performing sample preparation steps and can detect host defense toxins. In addition, advanced concepts in truly three dimensional functional polymer structures and heterogeneous materials integration were demonstrated. Modeling and material characterization capabilities to not only understand hydrogels better but also to enable design of innovative applications based on hydrogels were also established. A representative assay was used to develop and test the systems including botulinum toxin detection. The MicroFluidic Tectonics platform has broad potential applications across all layers of BC detection, analysis and response as well as many non BC warfare applications such as environmental toxicology, clinical detection and diagnosis, chemical synthesis, etc. DTIC Biochemistry; Detection; Fluidics 20050173508 California Univ., San Diego, La Jolla, CA USA Effect of Gravity on Sheared Turbulence Laden With Bubbles or Droplets Lasheras, Juan C.; Oct. 2004; 128 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): N00014-96-1-0213 Report No.(s): AD-A432992; 2259AV; ONR-TR-333; No Copyright; Avail: Defense Technical Information Center (DTIC) This report studies the dynamics of particle-laden turbulent flows. Specifically, it addresses the effect of the turbulence on the concentration field and drift velocity of spherical particles. The coupling between the particle accumulation and the modification of the drift velocity is also investigated. Turbulent flows with and without mean shear are analyzed and the effect of the turbulent length scales on the behavior of the particles is described. The effect of the density ratio between the disperse and the continuous phase was considered in the two extreme cases of water droplets in air (1000) and air bubbles in water (1/1000). DTIC Bubbles; Drops (Liquids); Gravitational Effects; Turbulence; Turbulent Flow 116 35 INSTRUMENTATION AND PHOTOGRAPHY Includes remote sensors; measuring instruments and gages; detectors; cameras and photographic supplies; and holography. For aerial photography see 43 Earth Resources and Remote Sensing. For related information see also 06 Avionics and Aircraft Instrumentation; and 19 Spacecraft Instrumentation and Astrionics. 20050169805 Deutsche Forschungsanstalt fuer Luft- und Raumfahrt, Berlin, Germany Martian Valley Networks andAssociated Fluvial Features as Seen by the Mars Express High Resolution Stereo Camera (HRSC) Jaumann, R.; Reiss, D.; Frei, S.; Scholten, F.; Grinner, K.; Roatsch, T.; Matz, K D.; Hauber, E.; Mertens, V.; Hoffmann, H., et al.; Lunar and Planetary Science XXXVI, Part 10; [2005]; 2 pp.; In English; See also 20050169793; Original contains black and white illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document Our objective is to characterize the internal structure of valley networks based on small-scale features that are related to fluvial processes. In order to map the features we used the data of ESA s Mars Express High Resolution Stereo Camera (HRSC) [1]. As HRSC is a stereo camera the three-dimensional structure of small inner valley features can be resolved providing quantitative information on transport rates and mass balances. Although the age differences between the valley floors and the surroundings are large and therefore stand for low average erosion rates, the estimated discharges indicate higher erosion activities and therefore shorter periods for the valley formation, which may be caused by episodic flooding events. Derived from text Cameras; Mars Express; Mass Distribution; High Resolution 20050169861 Lawrence Livermore National Lab., Livermore, CA Top Level User Specifications for Mask Inspection Microscope Barty, A.; Taylor, J. S.; Jan. 31, 2002; 18 pp.; In English Report No.(s): DE2004-15003402; UCRL-CR-148215; No Copyright; Avail: Department of Energy Information Bridge This document compiles top-level user specifications for an EUV microscope for characterizing EUVL mask defects. Two broad categories of application are considered: (1) emulation of the imaging characteristics of a stepper for printability analysis (AIM mode); and (2) high-resolution imaging for obtaining a more detailed characterization of defects or mask features. It is generally assumed that the mask defects that are to be characterized have been located by a previous inspection procedure and the spatial coordinates of the defect can be transferred to the microscope. NTIS Imaging Techniques; User Requirements; Microscopes; Ultraviolet Microscopy 20050169862 Lawrence Livermore National Lab., Livermore, CA Use of a Superconducting Tunnel Junction for X-Ray Fluorescence Spectroscopy Hiller, L. J.; Mar. 06, 2001; 132 pp.; In English Report No.(s): DE2004-15003411; UCRL-LR-143344; No Copyright; Avail: Department of Energy Information Bridge A superconducting tunnel junction (STJ) in combination with a superconducting absorber of radiation may function as a highly resolving x-ray spectrometer. Electronic excitations, or quasiparticles, are created when a superconductor absorbs an x-ray and are detected as an excess tunnel current through the junction. The number of quasiparticles created and the magnitude of the excess current is proportional to the energy of the absorbed x-ray. This is similar to existing semiconductor-based spectrometers that measure electron-hole pairs, but with 1000 times more excitations. The energy measurement therefore can be up to 30 times more precise with a superconducting detector than with a semiconductor detector. This work describes the development and testing of an STJ spectrometer design for x-ray fluorescence applications. First, the basic principles of the STJ spectrometer are explained. This is followed by detailed simulations of the variance in the number of quasiparticles produced by absorption of an x-ray. This variance is inherent in the detector and establishes an upper limit on the resolving power of the spectrometer. These simulations include effects due to the materials used in the spectrometer and to the multilayer structure of the device. Next, the spectrometer is characterized as functions of operating temperature, incident x-ray energy, and count rate. Many of these tests were performed with the spectrometer attached to a synchrotron radiation port. Finally, example x-ray fluorescence spectra of materials exposed to synchrotron radiation are presented. These 117 materials are of interest to semiconductor processing and structural biology, two fields that will benefit immediately from the improved resolving power of the STJ spectrometer. NTIS Semiconductors (Materials); Spectrometers; Spectroscopy; Superconductivity; Superconductors (Materials); Tunnel Junctions; X Ray Fluorescence; X Ray Spectrometers 20050169993 Hawaii Univ., Honolulu, HI, USA One Spectrometer, Two Spectra: Complementary Hemispherical Reflectance and Thermal Emission Spectroscopy Using a Single FTIR Instrument Hamilton, V. E.; Lucey, P. G.; Lunar and Planetary Science XXXVI, Part 8; [2005]; 2 pp.; In English; See also 20050169945; Original contains color illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document The Hawai’i Institute of Geophysics and Planetology (HIGP) at the University of Hawaii houses a new, dual-function FTIR spectrometer. This spectrometer provides an unprecedented opportunity to collect near-simultaneous (within tens of minutes) hemispherical reflectance and emission data of geologic samples, eliminating the disruption of particulate samples that necessarily occurs when such samples must be transported between laboratories. This dual setup also will facilitate cross-calibration between reflectance and emission spectra. Additional information is included in the original extended abstract. Author (revised) Infrared Spectrometers; Reflectance; Thermal Emission; Fourier Transformation 20050170610 Brown Univ., Providence, RI, USA Capabilities and Limitations of Infrared Reflectance Microspectroscopy Klima, R. L.; Pieters, C. M.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See also 20050170551; Original contains color illustrations Contract(s)/Grant(s): NAG5-13609; NNG04GG11G; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document Technological improvements in IR microspectroscopy have made it an increasingly appealing tool for planetary mineralogy. Microspectroscopy presents the prospect of examining small samples nondestructively and acquiring spectra that can be related to remote sensing observations. However, complications are introduced as a target beam size is reduced, and it is critical that limitations are understood. We present the results of a series of well constrained spectroscopic measurements, linking microspectroscopic data to traditionally collected reflectance spectra and petrologic information for the same rock. Author Infrared Radiation; Spectroscopic Analysis; Mineralogy 20050172152 Institute of Space and Astronautical Science, Sagamihara, Japan Inflight Calibration of Asteroid Multiband Imaging Camera Onboard Hayabusa: Preliminary Results Nakamura, R.; Ishiguro, M.; Nakamura, A. M.; Hirata, N.; Terazono, J.; Yamamoto, A.; Abe, M.; Hashimoto, T.; Saito, J.; Lunar and Planetary Science XXXVI, Part 14; [2005]; 2 pp.; In English; See also 20050172131; Original contains color and black and white illustrations; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document HAYABUSA is a Japanese sample return mission from a S-type near-Earth asteroid Itokawa and Asteroid Multiband Imaging Camera (AMICA) is one of the remote-sensing instruments. The field of view of 5.7 degree square is covered by a CCD chip consisting of 1024x1024 pixels with the 12 bit dynamic range. AMICA has a filter set similar, but not identical to the Eight Color Asteroids Survey (ECAS), which is the standard system for the ground-based asteroid taxonomy. In addition, four polarizers are attached on the surface of the CCD. While the imaging performance is a critical factor to investigate the surface topography, contaminants may blur the images as MSI on Near/Shoemaker. The ground-based measurements of a integrating sphere provided us with the radiometric calibration coefficients, which convert the output DN of AMICA to the input radiance. The preflight radiometric calibration, however, were conducted under the much higher temperature compared with the inflight operational environments. With the absolute radiometric calibration, we can estimate the Hapke parameters of Itokawa, which could be associated with the regolith properties. In addition, the local variations of the color and iron absorptions can be directly compared with the previous studies on Eros. In this article, we present some preliminary results 118 of inflight observations of AMICA to check the imaging performance and the absolute sensitivity in space. Additional information is included in the original extended abstract. Author (revised) CCD Cameras; Calibrating; Spacecraft Instruments; Multispectral Band Cameras 20050172163 Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, USA An Improved Instrument for Investigating Planetary Regolith Microstructure Nelson, R. M.; Hapke, B. W.; Smythe, W. D.; Manatt, K. S.; Eddy, J.; Lunar and Planetary Science XXXVI, Part 14; [2005]; 1 pp.; In English; See also 20050172131; Copyright; Avail: CASI; A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document The Opposition Effect (OE) is the non-linear increase in the intensity of light scattered from a surface as phase angle approaches 0 deg. It is seen in laboratory experiments and in remote sensing observations of planetary surfaces. Understanding the OE is a requirement for fitting photometric models which produce meaningful results about regolith texture. Previously we have reported measurements from the JPL long arm goniometer and we have shown that this instrument enables us to distinguish between two distinct processes which create the opposition surges, Shadow Hiding (SHOE) and Coherent Backscattering (CBOE). SHOE arises because, as phase angle approaches zero, shadows cast by regolith grains on other grains become invisible to the observer. CBOE results from constructive interference between rays traveling the same path but in opposite directions. Additional information is included in the original extended abstract. Author (revised) Regolith; Microstructure; Light Scattering; Optical Measuring Instruments; Planetary Surfaces 20050173197 Naval Research Lab., Washington, DC USA Airborne UXO Surveys Using the MTADS Nelson, H. H.; McDonald, J. R.; Wright, David; Apr. 2005; 140 pp.; In English; Original contains color illustrations Report No.(s): AD-A432363; NRL/MR/6110 05-8874; No Copyright; Avail: Defense Technical Information Center (DTIC) An airborne version of the MTADS vehicular towed array has been developed and demonstrated with the support of ESTCP Project 200031. The system is ideally suited to localizing burial caches of ordnance and establishing areas that are uncontaminated but also retains the capability of detecting, locating, and identifying individual ordnance items the size of 2.75-in. rocket warheads and larger. The system deploys a linear array of 7 Cs-vapor magnetometers spaced at 1.5-m intervals in a forward-mounted boom on a Bell Long Ranger helicopter. Two GPS units mounted on the forward boom provide positioning and roll and yaw measurements. An inertial measurement unit and a 3-axis fluxgate gradiometer redundantly provide additional attitude measurements. Laser, radar, and acoustic altimeters provide altitude information. A pilot guidance display provides survey progress and platform information in real time. All sensor data are recorded in a data acquisition computer mounted in one of the helicopter rear seats. This report documents the performance of the Airborne MTADS at three ranges containing both live ordnance and inert, seeded ordnance. DTIC Aerial Reconnaissance; Ammunition; Detection; Microinstrumentation; Ordnance; Sensors 20050173211 Naval Research Lab., Bay Saint Louis, MS USA Application of a Near-Infrared Slope Algorithm to Derive Optical Properties From High-Resolution, Hyperspectral Aircraft Imagery Gould, R. W., Jr.; Amone, R. A.; Sydor, M.; Kohler, D. D.; Bissett, W. P.; Oct. 2004; 16 pp.; In English Report No.(s): AD-A432395; NRL/PP/7330 04-0006; No Copyright; Avail: CASI; A03, Hardcopy Using new algorithms, we derive estimates of partitioned absorption (a) and scattering (b) coefficients from high-resolution, hyperspectral aircraft imagery collected with the PHILLS sensor. During May 2002, we conducted simultaneous ship and aircraft surveys in a dynamic environment in the northern Gulf of Mexico (coastal waters near Mobile Bay, Alabama). Optical measurements included hyperspectral remote sensing reflectance, partitioned absorption coefficients (phytoplankton, detrital, and colored dissolved organic matter components), beam attenuation (c), backscattering coefficient, HPLC phytoplankton pigment concentrations, and organic/inorganic particle loads. Our objectives arc to: (I) develop new algorithms to estimate optical properties from hyperspectral ocean color imagery; (2) apply to high-resolution aircraft imagery to characterize the spatial optical variability in an environment impacted by high concentrations of dissolved and particulate materials; and (3) perform an optical water mass classification on the aircraft imagery. The new optical classification system 119 based on the partitioned absorption coefficients is used to distinguish water masses and track coastal features. DTIC Algorithms; High Resolution; Imagery; Near Infrared Radiation; Optical Properties; Slopes 20050173218 Illinois Univ. at Urbana-Champaign, Urbana, IL USA Development of Artificial Haircell Sensors Liu, Chang; Apr. 2005; 37 pp.; In English Contract(s)/Grant(s): F49620-01-1-0496 Report No.(s): AD-A432406; AFRL-SR-AR-TR-05-0147; No Copyright; Avail: CASI; A03, Hardcopy Biological haircells are highly sensitive and yet robust mechanoreceptors that can respond to an extremely wide variety of physical, fluidical, and chemical stimulus. The variety of animals that use haircell, a simple mechanical transducer, for critical tasks is astonishing. This projected aimed to: (1) Learn from the biological systems about haircell sensor design, materials, and performance, and the way multiple sensors are organized; (2) Develop artificial haircell sensors that are inspired by design, materials, and dimensions of biological counterparts using advanced microfabrication strategies; (3) Characterize the performance of artificial haircell sensors and validate the performance of individual sensors and groups of them for flow sensing applications. Apart from the objectives of gaining better performance in terms of combined sensitivity and robustness, the use of bioinspired haircell sensors have other benefits that are important for the military. Sensors are very important for military platforms such as remote wireless sensors and various mobile platforms. However, the cost of developing custom sensors is very high due to the high cost (millions of dollars) and long duration (several years) of sensor development. It is anticipate that the modualar sensor concept will significantly reduce the time it takes to develop a certain sensor and to enable low cost development efforts in the future. DTIC Biological Effects; Detection; Mechanical Properties 20050173249 Naval Postgraduate School, Monterey, CA USA Evolution of Boundary Layer Height in Response to Surface and Mesoscale Forcing Moore, Matthew J.; Mar. 2005; 75 pp.; In English; Original contains color illustrations Report No.(s): AD-A432473; No Copyright; Avail: Defense Technical Information Center (DTIC) This thesis study focuses on understanding the dissipation processes of the stratocumulus deck after sunrise. This objective is met through careful analyses of observational data as well as model simulations. Measurements from the Marine Atmosphere Measurement Lab (MAML) of the Naval Postgraduate School (NPS) are used in this study. In particular, the half-hourly wind profiler/Radio Acoustic Sounding System (RASS) measurements were used to determine the boundary layer top and the evolution of the boundary layer mean thermodynamic properties during the cloud breakup period. Measurements from a laser ceilometer and the routine surface measurements are also used to detect the variation of cloud base height, the evolution of the cloud deck, and the onset of sea breeze. These measurements revealed the increase of the boundary layer depth after sunrise followed by a decrease of the boundary layer depth after the onset of the sea breeze, which points to the role of surface heating and sea breeze development in modulating cloud evolution. The effects of surface heating and sea breeze are further tested using a 1-dimensional mixed layer model modified for coastal land surfaces. DTIC Boundary Layers; Mesoscale Phenomena; Radar Equipment; Radio Transmitters; Sounding 20050173301 Georgia Inst. of Tech., Atlanta, GA USA Analysis of Soil and Environmental Processes on Hyperspectral Infrared Signatures of Landmines Cathcart, J. M.; Bock, Robert D.; Campbell, Ricardo; Dec. 2004; 8 pp.; In English; Original contains color illustrations Report No.(s): AD-A432578; No Copyright; Avail: Defense Technical Information Center (DTIC) Georgia Tech is in the second year of a Multi-University Research Initiative designed to study the impact of environmental processes on optical signatures. In particular, this program is conducting phenomenological studies on hyperspectral and polarimetric signatures of various target classes in the visible and infrared wavebands. Initial research studies have focused on landmines and the impact of various environmental factors and processes (e.g., subsurface processes) on the resultant spectral infrared signatures. A variety of approaches have been employed in this research to gain a better understanding of the impact of the environment on the spectral and polarimetric characteristics of soil and landmine signatures. These approaches include theoretical analyses, physics-based signature modeling, field measurements, and laboratory studies. We will present results from our research into the use of a physics-based, hyperspectral signature model 120 as an analysis tool for landmine-related phenomenology studies. Results from these studies will be presented that underscore the importance of incorporating the subsurface processes into the signature analyses and the impact of these processes on detection algorithm development. The results of these analyses have been propagated to algorithm developers to permit the creation of more robust processing techniques based on these physical analyses and models. DTIC Environments; Imagery; Infrared Radiation; Infrared Signatures; Mines (Ordnance); Reflectance; Signatures; Soils; Spectrometers 20050173305 Michigan Univ., Ann Arbor, MI USA Multiple Model Particle Filtering For Multi-Target Tracking Hero, Alfred; Kreucher, Chris; Kastella, Keith; Dec. 2004; 33 pp.; In English; Original contains color illustrations Report No.(s): AD-A432588; No Copyright; Avail: Defense Technical Information Center (DTIC) This paper addresses the problem of tracking multiple moving targets by recursively estimating the joint multitarget probability density (JMPD). Estimation of the JMPD is done in a Bayesian framework and provides a method for tracking multiple targets which allow nonlinear target motion and measurement to state coupling as well as non-Gaussian target-state densities. We utilize an implementation of the JMPD method based on particle filtering (PF) techniques. The details of this method have been presented elsewhere 1. One feature of real targets is that they are poorly described by a single kinematic model Target behavior may change dramatically i.e. targets may stop moving or begin rapid acceleration. To address this fact we evaluate the use of the adaptive target tracking strategy known as the interacting multiple model (IMM) algorithm. The IMM uses multiple models for target behavior and adaptively determines which model(s) are the most appropriate at each time step based on sensor measurements. We demonstrate the applicability of the IMM to a PF-based multitarget tracker in two settings. First we consider the traditional application of tracking targets that switch between kinematic modes. The target motion used is field data recorded during a military battle simulation and includes multiple modes of target behavior. Our investigation is distinguished from prior efforts in that it is concerned with multiple targets and real target motion data and utilizes a PF implementation. Second we present a nontraditional reinterpretation of the multiple model filter as multiple models on the state of the filter rather than on the state of the target. We find that this strategy is able to automatically detect model violations and compensate by altering the filter model which results in improved target tracking. DTIC Algorithms; Signal to Noise Ratios; Tracking (Position) 20050173308 Massachusetts Inst. of Tech., Lexington, MA USA Adaptive Beamforming for SAR Ambiguity Rejection Benitz, Gerald; Dec. 2004; 25 pp.; In English; Original contains color illustrations Report No.(s): AD-A432610; No Copyright; Avail: Defense Technical Information Center (DTIC) The Lincoln SPARTA program is developing next-generation phased arrays for enhanced radar performance and efficiency. One novel capability being explored is simultaneous operation of MTI (moving target indicator) and SAR (synthetic aperture radar) imaging two functions that are usually mutually exclusive. MTI scans large areas quickly using short integration (^10 msec) and low bandwidth (^10 MHz). SAR in contrast stares for seconds at each location and has high bandwidth (^600 MHz). Simultaneous operation requires multiple beams, frequency-division multiplexing, and synchronized pulsing. Also, MTI requires a higher PRF (pulse-repetition frequency) than SAR, and multiple PRFs for ambiguity resolution. Hence, it is desirable for SAR to function with MTI pulse scheduling. This presentation explores the use of adaptive beamforming to extend SAR performance to unfavorable PRFs. A low PRF implies that Doppler-ambiguous clutter is near the main lobe, while a high PRF implies that range-ambiguous clutter is near the main lobe.An image-domain, minimum-variance beamformer is presented which attenuates ambiguous clutter, adapting the beam uniquely at each location (pixel) in the image. A simulated SAR collection at high PRF using a 3-beam combiner demonstrates a practical, limited degree-of-freedom implementation. DTIC Adaptation; Ambiguity; Beamforming; Moving Target Indicators; Phased Arrays; Synthetic Aperture Radar 20050173314 Massachusetts Inst. of Tech., Lexington, MA USA Long CPI Wideband GMTI Yegulalp, Ali; Dec. 2004; 30 pp.; In English; Original contains color illustrations Report No.(s): AD-A432617; No Copyright; Avail: Defense Technical Information Center (DTIC) 121 The conventional approach to GMTI uses narrowband signals and a short coherent processing interval (CPI). In this talk, we examine some of the fundamental theoretical issues involved in GMTI with wideband signals and long CPIs (WL-GMTI). The possibility of wideband long CPI GMTI has received some attention in recent years and there are a number of potential benefits: 1) Improved minimum detectable velocity (MDV). 2) Detection of targets with zero radial velocity (but non-zero tangential velocity. 3) Better fit with dual-use SAR/GMTI architectures. 4) Less demanding array requirements (shorter and/or sparser arrays). 5) Greater robustness to clutter internal motion. The most convenient framework for WL-GMTI is a post-SAR architecture where each spatial channel is pre-processed with synthetic aperture radar (SAR) image processing. The post-SAR architecture is the natural generalization of post-Doppler STAP to the wideband long-CPI case. Exact steering vectors in the post-SAR framework are computed analytically for constant-velocity targets assuming a calibrated array. The steering vectors can be used with algorithms such as the GLRT or AMF to perform adaptive detection on the post-SAR data. We also derive a simple exact expression for SINR loss when the covariance is known exactly. The loss is a two-dimensional function of both target velocity components indicating the capability to detect both radial and non-radial target motion. The final section of this talk examines WL-GMTI performance bounds based on optimal Bayesian detection. In particular we study how detection performance varies as a function of the number of pixels that the moving target ‘smears’ over in the SAR image. There is a surprising improvement in detection performance when the clutter has strong non-Gaussian tails. In at least some cases, it appears that much of the performance can be achieved with a simple sub-optimal detector. DTIC Broadband; Moving Target Indicators; Synthetic Aperture Radar 20050173320 QinetiQ Ltd., London, UK A Novel Technique for Broadband Singular Value Decomposition McWhirter, John; Baxter, Paul D.; Dec. 2004; 22 pp.; In English; Original contains color illustrations Report No.(s): AD-A432624; No Copyright; Avail: Defense Technical Information Center (DTIC) The singular value decomposition (SVD) is a very important tool for narrowband adaptive sensor array processing. The SVD decorrelates the signals received from an array of sensors by applying a unitary matrix of complex scalars which serve to modify the signals in phase and amplitude. Because the transformation is unitary the associated singular values represent the true energy associated with each of the decorrelated components so the signal and noise subspaces may sometimes be separated. In broadband applications or a situation in which narrowband signals have been convolutively mixed the received signals cannot be represented in terms of phase and amplitude. Instantaneous decorrelation using a unitary matrix is no longer sufficient to separate them. It is necessary to impose decorrelation not just at the same time instant for all signals but over a suitably chosen range of relative time delays. This is referred to as strong decorrelation. Implementing strong decorrelation involves the application of a matrix of suitably chosen FIR filters and if each filter is represented in terms of its z-transform this takes the form of a polynomial matrix. We generalize the SVD to broadband adaptive sensor arrays by requiring the strong decorrelation to be implemented using a paraunitary polynomial matrix A paraunitary polynomial matrix has several important (closely related) properties. 1. It represents a multi-channel all-pass filter. 2. It preserves the total signal energy. 3. It preserves the total energy at every frequency. In this paper we describe a novel technique for computing the required paraunitary matrix and show how the resulting broadband SVD algorithm can be applied in practice e.g. to identify broadband signal and noise subspaces or to separate a multi-channel broadband adaptive filtering problem into a set of independent single-channel problems. DTIC Adaptation; Broadband; Decomposition; Narrowband 20050173321 Massachusetts Inst. of Tech., Lexington, MA USA Threshold Region Performance Prediction for Adaptive Matched Field Processing Localization Lee, Nigel; Richmond, Christ D.; Mar. 2004; 11 pp.; In English; Original contains color illustrations Report No.(s): AD-A432626; No Copyright; Avail: Defense Technical Information Center (DTIC) Matched field processing (MFP) provides a means of attaining the full gains available from the shallow-water acoustic channel in passive sonar signal processing. By modeling the full field structure of acoustic signals propagating in the ocean MFP offers the potential for both detection gain (through its better signal model) and localization gain (through its additional discrimination capability in range and depth) over traditional planewave processing. However, high spatial ambiguities and mismatch present formidable challenges in practice limiting the performance gains that are realistically achievable with MFP. Prediction of MFP localization performance is a challenging problem. MFP replica (steering) vectors can be highly ambiguous in range and depth resulting in significant non-local estimation errors at low signal-to-noise ratios (SNRs)-errors not modeled by traditional localization measures such as the Cramer-Rao bound. Recent work has demonstrated the accuracy of an 122 interval-error-based method referred to herein as the ‘method of interval errors’ (MIE), in predicting mean- squared error localization performance well into the threshold region where non-local errors may dominate. This work uses the MIE to predict the mean-squared error accuracy of MFP range and depth estimates for two well-known approaches: (i) conventional beamforming (equivalent to maximum likelihood estimation for white noise) and (ii) Capon-MVDR adaptive beamforming. Simulation results will characterize localization performance as a function of SNR, for apertures and environments of interest. Particular attention will be given to the ‘threshold SNR’ (below which localization performance degrades rapidly due to global estimation errors) and to the minimum SNR required to achieve acceptable range/depth localization. Initial work will also be presented assessing the MIE’s potential to characterize localization performance in the presence of mismatch. DTIC Adaptation; Performance Prediction; Position (Location); Signal to Noise Ratios; Signal Transmission; Sound Waves 20050173325 Army Communications-Electronics Command, Fort Monmouth, NJ USA Observations in Improved Geolocation Accuracy Based on Signal-Dependent and Non-Signal Dependent Errors Porr, Lauren E.; Faragher, Gregory P.; Kosinski, John A.; Borowick, John J.; Dec. 2004; 5 pp.; In English; Original contains color illustrations Report No.(s): AD-A432631; No Copyright; Avail: Defense Technical Information Center (DTIC) This paper examines the effects of signal-dependent versus non-signal-dependent errors on the geolocation accuracy that a state-of-the-art system based on Commercial-off-the-Shelf (COTS) equipment can potentially achieve. The results provide a focus for research in improvements of geolocation accuracy. The studies make use of a simulation tool developed by the Intelligence and Information Warfare Directorate (I2WD) at Fort Monmouth, NJ; supported by CACI Technologies, Inc., Eatontown, NJ; and the Research Associates of Syracuse (RAS) , Syracuse, NY. DTIC Accuracy; Direction Finding; Emitters; Errors; Position (Location); Rescue Operations 20050173328 Army Research Lab., Adelphi, MD USA Minimizing 1/f Noise in Magnetic Sensors with a MEMS Flux Concentrator Edelstein, A. S.; Fischer, Greg; Pulskamp, Jeff; Pedersen, Michael; Bernard, William; Cheng, Shu F.; Dec. 2004; 7 pp.; In English; Original contains color illustrations Report No.(s): AD-A432634; No Copyright; Avail: Defense Technical Information Center (DTIC) New approaches offer the promise of providing energy efficient, low cost, small, and highly sensitive magnetic sensors. However, the 1/f noise of these new types of sensors is a major obstacle. Many army applications, such as detecting moving targets, require sensitivity at low frequencies. This paper reports development of a device, the MEMS flux concentrator, invented at ARL, that minimizes the effect of 1/f noise in sensors. The device accomplishes this by shifting the operating frequency to higher frequencies where 1/f noise is much lower. This shift is accomplished by modulating the magnetic field before it reaches the sensor. In our device, the magnetic sensor, a GMR sensor, is placed between flux concentrators that have been deposited on MEMS flaps. The motion of the MEMS flaps modulates the field by a factor of 3 at frequencies from 8 to 15 kHz. The MEMS flux concentrator should increase the sensitivity of many magnetic sensors by two to three orders of magnitude. An equally important benefit is that, because it is a modulation technique, it eliminates the problem of dealing with the large DC bias of most magnetoresistive sensors. DTIC Concentrators; Microelectromechanical Systems; Microinstrumentation; Sensors 20050173335 Army Test and Evaluation Command, Aberdeen Proving Ground, MD USA Standardized UXO Technology Demonstration Site Open Field Scoring Record Number 354 Overbay, Larry, Jr.; Archiable, Robert; McClung, Christina; Jan. 2005; 66 pp.; In English; Original contains color illustrations Report No.(s): AD-A432657; ATC-8915; No Copyright; Avail: Defense Technical Information Center (DTIC) This scoring record documents the efforts of Shaw Environmental, Inc. to detect and discriminate inert unexploded ordnance (UXO) utilizing the YPG standardized UXO Technology Demonstration Site Open Field. The scoring record was coordinated by Larry Overbay and by the Standardized UXO Technology Demonstration Site Scoring Committee. Organizations on the committee include the U.S. Army Corps of Engineers, the Environmental Security Technology Certification Program, the Strategic Environmental Research and Development Program, the Institute for Defense Analysis, 123 [...]... treated For robotics see 63 Cybernetics, Artificial Intelligence, and Robotics; and 54 Man/System Technology and Life Support 20050169575 Ulster Coll., Newtownabbey, UK Body-Obstructed Fading Characteristics of an In-Ward 2.45 Biomedical Telecommand Link Scanlon, W G.; Cumley, G C.; Evans, N E.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp 38 0 -38 3; In English; See also... PRODUCTION AND CONVERSION Includes specific energy conversion systems, e.g., fuel cells; and solar, geothermal, windpower, and waterwave conversion systems; energy storage; and traditional power generators For technologies related to nuclear energy production see 73 Nuclear Physics For related information see also 07 Aircraft Propulsion and Power; 20 Spacecraft Propulsion and Power; and 28 Propellants and. .. DE2004- 834 031 ; No Copyright; Avail: Department of Energy Information Bridge The Linac Coherent Light Source (LCLS) undulator line will consist of 33 undulator segments separated by breaks of two different lengths The undulator segments are 3. 4-m-long permanent-magnet planar hybrid devices with a period length of 30 mm and a magnetic gap of approximately 6 mm Focusing quadrupoles, in a FODO lattice, and. .. predictions and tests, gears with backup ratios (rim thickness divided by tooth height) of 3. 3 and 1.0 produced tooth fractures, whereas a backup ratio of 0 .3 produced rim fractures For a backup ratio of 0.5, the experiments produced rim fractures and the predictions produced both rim and tooth fractures, depending on the initial geometry of the crack Good correlation between predicted and measured... Panel Spellman, Regina L.; Jones, Lisa E.; Lyle, Karen H.; Jackson, Karen E.; Fasanella, Edwin L.; April 2005; 21 pp.; In English Contract(s)/Grant(s): 23- 376-70 -30 -07 Report No.(s): NASA/ TM-2005-2 135 46; ARL-TR -33 48; L-19096; No Copyright; Avail: CASI; A 03, Hardcopy In support of recommendations by the Columbia Accident Investigation Board, a team has been studying the effect of debris impacting the reinforced... Rays; Gamma Rays; Exclusion; Abundance 43 EARTH RESOURCES AND REMOTE SENSING Includes remote sensing of earth features, phenomena and resources by aircraft, balloon, rocket, and spacecraft; analysis of remote sensing data and imagery; development of remote sensing products; photogrammetry; and aerial photography For related instrumentation see 35 Instrumentation and Photography 20050170566 Auburn Univ.,... No.(s): AD-A 432 899; ARO-42 831 .3- EL; No Copyright; Avail: Defense Technical Information Center (DTIC) Design, processing and characterization of high-speed implanted-apertured, lateral-current-injection, dielectric-mirror vertical cavity surface emitting laser and InGaAs based MEM detectors and mixers We have achieved following goals: I Designed 1,55 micron InP/InGaAs based tunnel junction structure and purchased... illustrations Report No.(s): AD-A 433 017; No Copyright; Avail: Defense Technical Information Center (DTIC) DoD Embedded Processing Applications: Future systems need: 1) Higher performance with reduced cost, size, weight, and power consumption; 2) Adaptability, flexibility, scalability, reconfigurability; 3) High bandwidth internal and network data communications DTIC Bandwidth; Communication Networks;... Frequency and Phase of a Compact, Low Jitter Modelocked Semiconductor Diode Laser Delfyett, Peter J., Jr; Mar 2005; 15 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): F30602-02-1-0170; Proj-2002 Report No.(s): AD-A 432 366; AFRL-SN-RS-TR-2005- 63; No Copyright; Avail: Defense Technical Information Center (DTIC) This research project was aimed at the stabilization of the frequency and. .. Contract(s)/Grant(s): Proj-AT 23 Report No.(s): AD-A 432 639 ; ERDC/CERL-TR- 03- 20; No Copyright; Avail: Defense Technical Information Center (DTIC) The Army maintains an aging inventory of over 1 43, 000 structures, many of which are in urgent need of maintenance and repair In some instances, these aging structures fail to meet prevailing seismic engineering codes In the USA alone, 30 percent of the Army’s structures use . Microinstrumentation; Sensors 200501 733 35 Army Test and Evaluation Command, Aberdeen Proving Ground, MD USA Standardized UXO Technology Demonstration Site Open Field Scoring Record Number 35 4 Overbay, Larry,. instruments and gages; detectors; cameras and photographic supplies; and holography. For aerial photography see 43 Earth Resources and Remote Sensing. For related information see also 06 Avionics and. English Report No.(s): AD-A 432 395; NRL/PP/ 733 0 04-0006; No Copyright; Avail: CASI; A 03, Hardcopy Using new algorithms, we derive estimates of partitioned absorption (a) and scattering (b) coefficients

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