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Conference on Photonics for Processors, Neural Networks, and Memories

作者： FRIDAY, WA HUDSON, TD KIRSCH, JC USA MISSILE COMMANDWEAPONS SCI DIRECTORATEREDSTONE ARSENALAL 35898

ISBN: (纸本)0819412759

The Weapons Sciences Directorate of the U.S. Army Missile Command has been directly involved in research and development of optical processing technology for several years. Extensive publications have described developments in several key areas of research. current efforts are aimed toward military applications, for which optical processing offers great potential for improved speed and performance in automatic target detection, location, and recognition. Research is directed toward overcoming the remaining technical issues. Topics of investigation include: spatial light modulator performance and use; photorefractive materials for data storage; Vander Lugt, joint transform, and acousto-optic correlator designs; neural network implementations for morphological transforms, region and texture segmentation, rapid training techniques; and composite filter design, development, and implementation. This paper describes progress and accomplishments in some of these areas, with projections for future work.

关键词： optical correlators optical filters Spatial light modulators Missiles optical signal processing Sensors Target recognition LCDs Electronics Neural networks

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Spaceflight optical disk recorder development

Spaceflight optical disk recorder development

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Enabling Technologies for High-Bandwidth Applications

作者： Jurczyk, Stephen G. Hines, Glenn D. Shull, Thomas A. NASA Langley Research Cent. Hampton VA USA

ISBN: (纸本)0819409642

Mass memory system based on rewriteable optical disk media are expected to play an important role in meeting the data system requirements for future NASA spaceflight missions. NASA has established a program to develop a high performance (high rate, large capacity) optical disk recorder focused on use aboard unmanned Earth orbiting platforms. An expandable, adaptable system concept is proposed based on disk drive modules and a modular controller. Drive performance goals are 10 gigabyte capacity, 300 megabit per second transfer rate, 10-12 corrected bit error rate, and 150 millisecond access time. This performance is achieved by writing eight data tracks in parallel on both sides of a 14 inch optical disk using two independent heads. System goals are 160 gigabyte capacity, 1.2 gigabits per second data rate with concurrent I/O, 250 millisecond access time, and two to five year operating life on orbit. The system can be configured to meet various applications. This versatility is provided by the controller. The controller provides command processing, multiple drive synchronization, data buffering, basic file management, error processing, and status reporting. Technology developments, design concepts, current status including a computer model of the system and a controller breadboard, and future plans for the drive and controller are presented.

关键词： optical recording

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Ray redistribution optics for high-feedback annular resonators ii: Resonator analysis with wave optics

Ray redistribution optics for high-feedback annular resonato...

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Laser Resonators and Coherent Optics: Modeling, Technology, and Applications 1993

作者： White, F.H. Campbell, R.D. Hiddleston, H.R. Lyman, D.D. Schafer, E.L. SAIC - Science Applications International Corporation

In an accompanying paper1, we described how current optical resonators used for power extraction from flowing annular gain generators are typically limited to high resonator magnifications. We proceeded to describe how the addition of a ray-redistribution optical pair can provide sufficient resonator feedback so that the effective resonator magnification can be made significantly lower, while preserving a filled-in output beam. We defined the geometric-optics equations for the design of this ray-redistribution optical pair, and showed an example of such a design. In the current paper, we consider resonator designs with a range of effective magnifications (1.2 to 2.95), and show how these resonators perform. Specifically, we analyze power extraction performance, internal power gains and losses, and resonator wavefront beam quality for this range of effective magnifications. As perturbations, we consider the effect of struts and compact leg misalignments. We find that, at the lower levels of magnification, the resonators produce more power but are more sensitive to perturbations. © 1993 SPIE. All rights reserved.

关键词： Resonators

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Method and instrument for retrieving total columnar water vapor from solar transmittance

Method and instrument for retrieving total columnar water va...

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Atmospheric Propagation and Remote Sensing ii

作者： Thome, Kurtis J. Smith, Mark W. Palmer, James M. Reagan, John A. Optical Sciences Cent./Univ. of Arizona Tucson AZ USA

ISBN: (纸本)081941204X

The design of a three-channel solar radiometer for obtaining total columnar water vapor using solar transmittance and differential absorption is presented. Water vapor transmittance is determined using a modified Langley approach and converted to columnar water vapor using a band model developed at the University of Arizona. Several cases are presented in which columnar water vapor amounts determined using the current instrument and method are compared to sounding balloon results. Tests using simulated data indicate that columnar water vapor may be retrieved with an uncertainty less than 10%.

关键词： Remote sensing

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CRITICAL HEAT-FLUX OF SUBCOOLED FLOW BOILING WITH WATER FOR HIGH HEAT-FLUX APPLICATION

CRITICAL HEAT-FLUX OF SUBCOOLED FLOW BOILING WITH WATER FOR ...

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2nd High Heat Flux engineering Conference

作者： INASAKA, F NARIAI, H SHIP RES INST DIV NUCL TECHNOLMITAKATOKYO 181JAPAN

Subcooled flow boiling in water is thought to be advantageous in removing high heat load of more than 10 MW/m2. Characteristics of the critical heat flux (CHF), which determines the upper limit of heat removal, are ve... 详细信息

ISBN: (纸本)0819412465

Subcooled flow boiling in water is thought to be advantageous in removing high heat load of more than 10 MW/m². Characteristics of the critical heat flux (CHF), which determines the upper limit of heat removal, are very important for the design of cooling systems. In this paper, studies on subcooled flow boiling CHF, which have been conducted by the authors, are reported. Experiments were conducted using direct current heating of stainless steel tube. For uniform heating conditions, CHF increment in small diameter tubes (1 - 3 mm inside diameter) and the CHF characteristics in tubes with internal twisted tapes were investigated, and also the existing CHF correlations for ordinary tubes (more than 3 mm inside diameter) were evaluated. For peripherally non-uniform heating conditions using the tube, whose wall thickness was partly reduced, the CHF for swirl flow was higher than the CHF under uniform heating conditions with an increase of the non-uniformity factor.

关键词： Heat flux Thermal engineering Data modeling Protactinium Astatine Cooling systems Liquids Data fusion Mendelevium Zirconium dioxide

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Three-dimensional grating optical retinal chip and stimulus-adaptive robotic vision

Three-dimensional grating optical retinal chip and stimulus-...

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Intelligent Robots and Computer Vision XI: Algorithms, Techniques, and Active Vision

作者： Lauinger, Norbert Inst. of Industrial Psychology Wetzlar 1 Federal Republic of Germany

ISBN: (纸本)0819410268

A cellular multilayer phase grating with hexagonal closest packing proves to be the ideal focal plane architecture for the human eye, and is thus also the best model for designing stimulus- adaptive robot eyes which achieve the spatial and chromatic performance of the human eye. Crystal-optical calculation of the retinal cellular multilayer chip and the resulting correlations between the physical stimulus parameters and the adaptive shifts in human vision at the retinal level give rise to a time-frequency diagram of the eye and its stimulus-adaptive latitudes, which will become relevant in the design of future chips for robot eyes with performance comparable to that of human vision. The current presentation shows that 3-D grating optical parameters ensure the frequency-related chromatic adaptive shifts (transition from photopic to scotopic vision in the Purkinje shift, Stiles-Crawford effects I/ii, Bezold-Bruecke phenomenon, chromatic adaptation to artificial light sources of different spectral composition, etc.) and also indicates what 3-D grating optical parameters are relevant to spatial transfer and adaptation, i.e., the time-related aspects in the time-frequency diagram (adaptation of the spatial modulation transfer function to the image parameters;log term for spatial adaptation to the intensity level;coding of spatial phase relationships between a fundamental spatial frequency and higher frequencies up to the third harmonic, etc.).

关键词： Computer vision

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ROBUST FAST MODEL-BASED RECOGNITION OF PARTIALLY OCCLUDED OBJECTS USING NORMALIZED INTERVAL VERTEX DESCRIPTORS 2

ROBUST FAST MODEL-BASED RECOGNITION OF PARTIALLY OCCLUDED OB...

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CONF ON SIGNAL PROCESSING, SENSOR FUSION, AND TARGET RECOGNITION 2

作者： PARRALOERA, R ERIVES, H THOMPSON, WE New Mexico State Univ. (United States)

ISBN: (纸本)0819411914

This paper deals with the problem of robust fast recognition of partially occluded or incomplete views of `flat' objects. Robustness is accomplished through hypothesis confirmation using complementary or supporting information available for the current hypothesis and by model-based hypothesis verification. Classification speed is obtained by pruning the hypothesis hierarchy using simple pruning procedures based on structural properties derived from current object representation. In addition, classification speed is also improved through the use of simple model-based decision making procedures instead of computationally expensive transformations. Normalized Interval Vertex Descriptors (NIVD) are used to represent objects. NIVDs are representations derived from the physical characteristics of an object (vertices and sides) that are easy to obtain, especially for polygon like shapes. They provide not only a compact representation, but they also allow the definition of features that can be used to speed up the classification process. Experimental results of this process are also included.

关键词： Model-based design Process modeling Image processing Image segmentation Object recognition Image processing algorithms and systems Binary data Classification systems Clocks Reconstruction algorithms

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Aircraft instrument design for in-situ tropospheric OH measurements by laser-induced fluorescence at low pressures

Aircraft instrument design for in-situ tropospheric OH measu...

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optical Methods in Atmospheric Chemistry

作者： Brune, William H. Stevens, Philip S. Mather, James H. The Pennsylvania State Univ. University Park PA USA

ISBN: (纸本)0819408808

The hydroxyl radical (OH) is important for many processes involved in tropospheric chemistry. For instance, it initiates the photochemical degradation of gases that cause global climate change, such as methane and the chlorofluorocarbon substitutes (HCFCs). Because of its reactivity, its abundances are less than 0.1 pptv. Thus, OH has been very difficult to measure accurately, despite its importance. Techniques have evolved, however, so that good measurements of tropospheric OH abundances are now possible. One of these techniques that is adaptable to aircraft measurements is the laser induced fluorescence detection of the OH radical in a detection chamber at low pressures, a technique first developed by R. J. O'Brien and T. M. Hard. Because OH is both excited and detected in the A2Σ+(υ′ = 0) &rarr X2ii(υ″ = 0) transition near 308 nm (approximately 10 milliwatts at 10 kHz repetition rate), significant laser generation of OH and interference signals from other trace gases are avoided. The current ground-based instrument, which can be readily adapted to aircraft, can detect OH abundances of 1.4 × 105 OH molecules cm-3 with S/N = 2 in 30 seconds, and 5 × 104 cm-3 in five minutes.

关键词： Atmospheric composition

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Characterization of a high density plasma source for dry develop 2

Characterization of a high density plasma source for dry dev...

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Advanced Techniques for Integrated Circuit Processing ii 1992

作者： Paranjpe, Ajit P. Davis, Cecil J. Semiconductor Process and Design Center Texas Instruments Inc. 13536 N. Central Expressway MS 944 DallasTX75265 United States

The nature of the dry develop process demands controllable ion energies for good etch selectivity, a large highly directional ion flux for good anisotropy, and a clean etch. As a part of the plasma characterization, the plasma density, the resist etch rate, the ion energy and the ion energy flux have been determined as a function of process conditions, for an inductively coupled plasma (ICP) source. The plasma density and ion flux increase linearly with antenna power. A factor of four variation in ion to neutral flux ratio could be achieved over the range of flow rates and power levels investigated. Independent control of the etch rate and selectivity is possible with the ICP system. However, eddy current heating of the wafer at high power levels causes loss of anisotropy. Feasibility of using an ICP for the DESIRE process is demonstrated. Good pattern linearity can be achieved for feature sizes ranging from 0.35-0.60 μm. The process latitude for the exposure time, silylation time, and etch conditions is wide. The etch is clean, exhibits good anisotropy and no proximity effects. The ICP etch system is an attractive choice for sub half micron patterning using DESIRE. © 1993 SPIE. All rights reserved.

关键词： Inductively coupled plasma

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PRODUCT design FOR PRODUCTIVITY AND INNOVATION WITH engineering THERMOPLASTICS AND THEIR BLENDS IN THE NINETIES

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MAKROMOLEKULARE CHEMIE-MACROMOLECULAR SYMPOSIA 1993年第1期75卷 55-66页

作者： BAILLY, C SEDEREL, WL Department of Technology General Electric Plastics Plasticslaan 14600 AC Bergen op Zoom The Netherlands

Companies must constantly improve their technologies to survive the competitive battle in the nineteen nineties and beyond. This now holds more than ever for producers of engineering thermoplastics, who traditionally have enjoyed significantly higher margins than the commodity plastic producers. In today's competitive environment it is vital to be the high quality, low cost producer. At the same time products and processes need to become ''greener''. The drivers call for specific R&D approaches focused at cost and ecological improvements of processes and products. Examples are: (i) novel catalysis with fewer process steps, higher yields and selectivity for the production of monomers and polymers. (ii) solvent-free polymerisation processes, resulting in lower investment cost, lower operating cost and the lack of solvent traces in the final product (iii) design of polymer modifications, e.g. higher flow and/or higher heat copolymers such that products can be produced in existing equipment resulting in acceptable Return-on-Investment (ROI). Higher flow products are specifically needed for thin-wall designs to allow optimum use of the high mechanical properties of engineering thermoplastics, making shorter processing cycles possible during moulding and bringing less material in the environment. This paper reviews various routes to high flow technology, such as improving processing window, molecular engineering and blends. The pull for these technology developments come from optical data storage, thin wall bumper and super thin note bloc computer applications. The need for greener products is addressed through improved flame and fire retardant product design.

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