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International Conference Neutrons in Research and Industry 1996

作者： Sredniawski, Joseph J. Debiak, T. Kamykowski, E. Rathke, J. Schmor, P. Milton, B. Stanford, G. Rogers, J. Boyd, J. Brondo, J. Northrop Grumman Advanced Technology and Development Center 1111 Stewart Avenue BethpageNY11714-3582 United States TRIUMF Technologies Inc. 4004 Westbrook Mall VancouverBCV6T 2A3 Canada Scientific Innovations Inc. 14 Oak Hill Lane East HamptonNY11937 United States

A Proof-of-Principle (POP) Contraband Detection System (CDS), is under construction at Northrop Grumman's Advanced Technology and Development Center. We employ gamma resonance absorption (GRA) to detect nitrogen or chlorine in explosives and certain forms of illegal drugs. Using tomography, 3-D images of the total density and selected element density are generated. These characteristics together may be utilized with considerable confidence in determining if contraband is present in baggage or cargo. The CDS employs a high current (>10 mA) DC electrostatic accelerator that provides a beam of protons at either 1.75 or 1.89 Mev. These high energy particles impinge upon a target coated with 13C or 34S. The resultant resonant gamma rays are preferentially absorbed in either 14N or 35C1. Because of the penetrating power of the gamma rays, this approach can be utilized for inspection of fully loaded aircraft containers such as the LD3. With proper design for handling baggage and with certain CDS design features not present in the POP, throughputs approaching 2000 bags/hour are estimated. Furthermore, the technology being developed for the CDS accelerator may have other applications such as for Boron Neutron Capture Therapy or Neutron Radiography. Our current program calls for testing of the POP CDS by late 1996. This paper presents the overall design, and characteristics of the CDS POP and the status of the program. © SPIE.

关键词： Gamma rays

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Spectral correlation of wideband target resonances

Spectral correlation of wideband target resonances

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Algorithms for Synthetic Aperture Radar Imagery III Conference

作者： Sabio, v USA RES LABADELPHIMD 20783

ISBN: (纸本)0819421383

The US Army Research Laboratory (ARL), working with the University of Maryland Department of Electrical engineering, recently developed a novel method for efficient recognition of resonances in imagery from ARL's ultra-wideband (UWB) SAR instrumentation system, currently being used in foliage- and ground-penetration studies. The recognition technique uses linear transforms (Fourier, wavelets, etc.) to provide a basis for the design of spectrally matched filters. Implementation of the technique is very straightforward: an expectation of the target ringdown is projected onto a transform basis set, yielding a set of spectral coefficients (the 'spectral template'). UWB SAR image data are projected onto the same basis set, yielding a second vector of coefficients (the 'spectral image'). A simple correlation coefficient is generated from the two vectors, providing a measure of co-linearity of the spectral template and the spectral image: higher correlation values indicate greater co-linearity. Exceeding a correlation threshold results in a target implemented--a single 32-megabyte bipolar SAR image can be processed in less than five minutes. Initial spectral-correlation efforts focused on canonical targets and the results have been widely reported. current studies are focusing on tactical targets, such as CUCvs. Early results on CUCvs have shown that sa single resonance-based template can be sued effectively in the recognition of tactical targets. Ongoing studies have demonstrated a substantial reduction in the false-alarm rate over results reported previously. These results, as well as improvements in the recognitions-processing stage, are reported in this paper.

关键词： ultra-wideband radar SAR foliage-penetration automatic target recognition resonance spectral correlation

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current COIL research in Samara

Current COIL research in Samara

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Fourth International Workshop on Iodine Lasers and Applications

作者： Nikolayev, v.D. P.N. Lebedev Physical Inst. Samara Russia

ISBN: (纸本)0819421510

Development of the high pressure singlet oxygen generator (SOG) is a very important aspect for chemical oxygen-iodine laser (COIL). Increasing of oxygen pressure up to 30 torr and more at conserving high O2(1Δ) yield and maintaining BHP temperature at minus (10 divided by 20) degrees Celsius permits us to decrease ration [H 2O]/[O2] to 5% and less. In this case COIL can operate successfully without a water vapor trap. With raising the total pressure Reynolds number increases too, diminishing boundary layers in supersonic nozzles and improving pressure recovery. The weight and dimensions of the SOG and laser become reduced for the same gas flow rate. For solving these problems the jet SOG has been suggested and developed in Lebedev Physical Institute, Samara Branch. The advantages of the jet SOG consist of the following: (1) Large and controlled specific surface of contact liquid-gas provides for high mass transfer efficiency. (2) High jets velocity guarantees fast basic hydrogen peroxide (BHP) surface renovation. (3) High gas velocity in the reaction zone diminishes O2(1Δ) quenching. (4) Efficient gas-liquid heat exchange eliminates the gas heating and generation water vapor due O2(1Δ) quenching. (5) Counterflowing design of the jet SOG produces the best conditions for self-cleaning gas flow of droplets in the reaction zone and gives the possibility of COIL operation without droplets separator. High pressure jet SOG has some features connected with intrachannel jet formation, free space jets reconstruction, interaction jets ensemble with counter moving gas flow and drag part of gas by jets, disintegrating jets, generation and separation of droplets, heat effects, surface renovation, impoverishment BHP surface by HO2- ions, moving solution film on the reaction zone walls, etc. In this communication our current understanding of the major processes in the jet SOG is set forth. The complex gas and hydrodynamic processes with heat and mass transfer, chemical reactions, g

关键词： Chemical lasers

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Knowledge, Control, and Reality: The Need for a Pluralistic view in Control Systems design

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IFAC Proceedings volumes 1996年第1期29卷 829-834页

作者： Manuel Liz Margarita vázquez Javier Aracil Facultad de Filosofía Dept. de Lógica y Filosofía de la Ciencia Universidad de La Laguna 38201 Canary Islands Spain Escuela Superior de Ingenieros Universidad de Sevilla Avda. Reina Mercedes s/n 41012 Sevilla Spain

Modelling is a key issue in Control Systems design. The model embodies the knowledge about the processto be controlled and is interiorized in some way by the controller, so the actions it takes are based on the model. However, the model never is unique. Different conceptual schemes and different languages produce alternate models. current control engineering illustrates the fact that inside scientifical and technological disciplines we are very often lead to adopting an unavoidable pluralisticperspective. With the help of new developments in recent epistemology and philosophy of science, some conceptual proposals will be made in order to analyze that pluralism.

关键词： epistemological aspects of modelling internal realism alternate descriptions conceptual schemes fuzzy modelling

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Optimization of resonant intersubband nonlinear optical susceptibility in semiconductor quantum wells: The coordinate transform approach

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Physical Review B 1996年第16期53卷 10887-10887页

作者： v. Milanović Z. Ikonić D. Indjin Faculty of Electrical Engineering University of Belgrade Bulevar Revolucije 73 11000 Belgrade Yugoslavia

A systematic procedure is proposed for the optimal design of quantum-well structures, which provide maximal resonant second-order susceptibility. The method is based on the coordinate transform. Starting from the linear harmonic-oscillator Hamiltonian, itself lacking any nonlinear susceptibility, it generates a family of asymmetric isospectral Hamiltonians in parametrized form. Their parameters are then varied to maximize the product of matrix elements relevant for nonlinear susceptibility. Practical realization of quantum-well structures having such optimized Hamiltonians is also discussed. values of nonlinear susceptibility obtained by this method are about equal to the best values reported in current literature. © 1996 The American Physical Society.

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developments in laser-line scanned undersea surface mapping and image analysis systems for scientific applications

Developments in laser-line scanned undersea surface mapping ...

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OCEANS

作者： F.M. Caimi D.M. Kocak v.L. Asper Department of Electrical and Software Engineering Harbor Branch Oceanographic Institution Inc. Fort Pierce FL USA Stennis Space Center University of Southern Mississippi MS USA

The ability to produce range maps of undersea objects has direct application in a variety of applications including robotic manipulation and control, collision avoidance and navigation, military detection, identification, and localization, and scientific research. Although systems have been proposed using acoustic sensing methodology, optical systems can provide higher resolution and improved discrimination at close range. This paper describes recent developments using a laser scanner to construct accurate range maps of marine snow aggregates at high resolution (200/spl times/200/spl times/200) and at range distances of less than 10 cm. The proposed method is also suitable (with modifications) for long range operation at up to 6 attenuation lengths. The system utilizes a triangulation sensing approach that is suited to low cost implementation through the use of a novel, patented method for obtaining position information. The approach is also compatible, with range gating methods for reduction of scattered light interference, at multiple attenuation lengths. A description of the system theoretical limitations, design tradeoffs, and practical design constraints is presented. The design approach and recent hardware and software implementation developed under NSF and University of Southern Mississippi sponsorship are described. Graphical displays showing underwater surface map images of marine snow are also presented. Examples of information obtainable from the surface map data reduction of marine snow images include range histogram, particle quantification, surface area and volume, and direction and speed of motion. Future goals and modifications for the system are discussed.

关键词： Surface emitting lasers optical attenuators Snow optical scattering Robot sensing systems Robot control Collision avoidance Navigation Acoustic signal detection Object detection

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design and analysis of a spaceborne lidar telescope

Design and analysis of a spaceborne lidar telescope

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Conference on current developments in optical design and engineering v

作者： FENG, C AHMAD, A AMZAJERDIAN, F UNIV ALABAMA CTR APPL OPTHUNTSVILLEAL 35899

ISBN: (纸本)0819418994

A spaceborne telescope has been designed and analyzed for a 2-micron solid state coherent lidar system operating on a satellite. The optical system consists of a large off-axis reflective telescope, a large-aperture diffractive scanner, an image derotator and a lag angle compensator. Due to the orbiting motion of the satellite and scanning, the boresight of the telescope shifts during the round trip travel time of the laser pulses to the target. In a coherent lidar system utilizing optical heterodyne detection, the relative alignment of the received signal with respect to the local oscillator beam is particularly critical. Two compensators have been designed to correct the boresight errors as well as the wavefront errors caused by beam wandering due to the boresight changes. Several design approaches for the compensators have been investigated. The optical and optomechanical design issues for such a system are discussed. The results of optical performance, modeling, and tolerance analysis for the telescope are also presented.

关键词： optical design AND MODELING LARGE REFLECTIvE OPTICS DIFFRACTIvE OPTICS TOLERANCE ANALYSIS BORESIGHT SHIFT COMPENSATION LIDAR COHERENT LASER RADAR SATELLITE

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Personal project management for optical design

Personal project management for optical design

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current developments in optical design and engineering v

作者： Weller, Scott W. Optikwerk Inc. Rochester NY USA

current optical design software provides little support for the mundane human oriented tasks of personal project management. Project management tools from other domains are not readily applied to the optical design pr... 详细信息

ISBN: (纸本)0819418994

关键词： optical systems

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DEMOS III: new possibilities

DEMOS III: new possibilities

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current developments in optical design and engineering v

作者： Gan, Michael A. Zhdanov, Dmitriy D. Novoselskiy, vadim v. Fedorov, Alexander O. Potyemin, Igor S. Ustinov, Sergey I. Starkov, A.A. Smirnov, S.E. S.I. Vavilov State Optical Inst. St. Petersburg Russia

ISBN: (纸本)0819418994

DEMOS software was developed in 1973 - 1975 for design of optical systems (OS) with conventional and holographic elements. It was constantly improved because of the necessity to solve a wide range of tasks dealing with display systems, lenses, multispectral systems for optical electronic units, and IR systems. A new version of DEMOS III was developed in 1994, and is an integrated dialogue system for simulation and design of a wide range of OS on personal computers compatible with IBM-PC. This article deals with the new possibilities of DEMOS-PC, version 3.

关键词： optical systems

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Characterization of abnormal dispersion liquids in the ultraviolet spectral region

Characterization of abnormal dispersion liquids in the ultra...

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current developments in optical design and engineering v

作者： Petrova, Maria v. Petrovsky, Gury T. Plyukhin, Andrei G. Tolstoy, Michael N. Robb, Paul N. Sigler, Robert D. S.I. Vavilov State Optical Inst. St. Petersburg Russia

ISBN: (纸本)0819418994

Abnormal dispersive liquids have proven quite useful in the design of apochromatic optical systems for the visible and ultraviolet spectral regions. Furthermore, liquids with extended ultraviolet transmission can be very useful in the design of optical systems for use in the ultraviolet, whether or not they are abnormally dispersive. The results of investigations into optical properties of several liquids transparent in the ultraviolet are presented. Intense Uv irradiation of the liquids was found to produce changes in both the Uv transmission and refractive index. Methods of preventing these changes through the addition of a special chemical were investigated. The optical property measurements were made at the vavilov State optical Institute, St. Petersburg, Russia in collaboration with the Lockheed Palo Alto Research Laboratory, Palo Alto, California.

关键词： optical systems

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