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SIMPLE APPROACH TO REFLECTANCE ANALYSIS OF BIREFRINGENT STRATIFIED FILMS

APPLIED OPTICS 1991年第28期30卷 4017-4018页

作者： KNOESEN, A []The author is with the Department of Electrical Engineering Computer Science Organized Research Program on Polymeric Ultrathin Film Systems University of California Davis Davis California 95616

A simple analysis is presented of reflectance from a stratified uniaxial media with the optic axes parallel or perpendicular to the plane of incidence.

关键词： UNIAXIAL FILMS POLED POLYMERS THIN FILM BIREFRINGENT

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FIELD SAMPLING OF RESIDUAL AVIATION GASOLINE IN SANDY SOIL

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GROUND WATER MONITORING AND REMEDIATION 1991年第2期11卷 107-120页

作者： OSTENDORF, DW LEACH, LE HINLEIN, ES XIE, YF 1 David W. Ostendorf is an associate professor in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Dr. Ostendorf is a registered professional engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Water Well Association.2 Lowell E. Leach is an environmental engineer with the Robert S. Kerr Environmental Research Laboratory of the U.S. Environmental Protection Agency (RS Kerr Environmental Research Laboratory U.S. EPA P.O. Box 1198 Ada OK74820). Leach received his B.S. ingeological engineering at the University of Oklahoma in 1959 and has been a registered professional engineer in Oklahoma since 1966. With 29 years of experience in field applications of geological engineering he is responsible for developing methodology for sampling ground water and subsurface materials for the Robert S. Kerr Environmental Research Laboratory.3 Erich S. Hinlein is a research assistant in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include ground water pollution hazardous waste site investigation and transport processes in unconfined aquifers. Hinlein graduated with a B.S. in electrical and computer engineering from the University of Massachusetts at Amherst in May 1985 and entered the Environmental Engineering Master's Degree Program in January 1989.4 Yuefeng Xie is a postdoctoral research associate in the Environmental Engineering Program of the Civil E

Two complementary field sampling methods for the determination of residual aviation gasoline content in the contaminated capillary fringe of a fine, uniform, sandy soil were investigated. The first method featured field extrusion of core barrels into pint-size Mason jars, while the second consisted of laboratory partitioning of intact stainless steel core sleeves. The barrel extrusion procedure involved jar headspace sampling in a nitrogen-filled glove box, which delineated the 0.7m thick residually contaminated interval for subsequent core sleeve withdrawal from adjacent boreholes. Soil samples removed from the Mason jars (in the field) and sleeve segments (in the laboratory) were subjected to methylene chloride extraction and gas chromatographic analysis to compare their aviation gasoline content. The barrel extrusion sampling method yielded a vertical profile with 0.10m resolution over an essentially continuous 5.0m interval from the ground surface to the water table. The sleeve segment alternative yielded a more resolved 0.03m vertical profile over a shorter 0.8m interval through the capillary fringe. The two methods delivered precise estimates of the vertically integrated mass of aviation gasoline at a given horizontal location, and a consistent view of the vertical profile as well. In the latter regard, a 0.2m thick lens of maximum contamination was found in the center of the capillary fringe, where moisture filled all voids smaller than the mean pore size. The maximum peak was resolved by the core sleeve data, but was partially obscured by the barrel extrusion observations, so that replicate barrels or a half-pint Mason jar size should be considered for data supporting vertical transport analyses in the absence of sleeve partitions.

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ROLE OF SIMULATION IN RAPID PROTOTYPING FOR CONCEPT DEVELOPMENT

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NAVAL ENGINEERS JOURNAL 1991年第3期103卷 204-211页

作者： KING, JF BARTON, DE J. Fred King:is the manager of the Advanced Technology Department for Unisys in Reston Virginia. He earned his Ph.D. in mathematics from the University of Houston in 1977. He has been principal investigator of research projects in knowledge engineering pattern recognition and heuristic problem-solving. Efforts include the development of a multi-temporal multispectral classifier for identifying graincrops using LANDSAT satellite imagery data for NASA. Also as a member of the research team for a NCI study with Baylor College of Medicine and NASA he helped develop techniques for detection of carcinoma using multispectral microphotometer scans of lung tissue. He established and became technical director of the AI Laboratory for Ford Aerospace where he developed expert scheduling modeling and knowledge acquisition systems for NASA. Since joining Unisys in 1985 he has led the development of object-oriented programming environments blackboard architectures data fusion techniques using neural networks and intelligent data base systems. Douglas E. Barton:is manager of Logistics Information Systems for Unisys in Reston Virginia. He earned his B.A. degree in computer science from the College of William and Mary in 1978 and did postgraduate work in London as a Drapers Company scholar. Since joining Unisys in 1981 his work has concentrated on program management and software engineering of large scale data base management systems and design and implementation of knowledge-based systems in planning and logistics. As chairman of the Logistics Data Subcommittee of the National Security Industrial Association (NSIA) he led an industry initiative which examined concepts in knowledge-based systems in military logistics. His responsibilities also include evaluation development and tailoring of software engineering standards and procedures for data base and knowledge-based systems. He is currently program manager of the Navigation Information Management System which provides support to the Fleet Ballistic Missile Progr

A valuable technique during concept development is rapid prototyping of software for key design components. This approach is particularly useful when the optimum design approach is not readily apparent or several known alternatives need to be rapidly evaluated. A problem inherent in rapid prototyping is the lack of a "target system" with which to interface. Some alternatives are to develop test driver libraries, integrate the prototype with an existing working simulator, or build one for the specific problem. This paper presents a unique approach to concept development using rapid prototyping for concept development and scenario-based simulation for concept verification. The rapid prototyping environment, derived from artificial intelligence technology, is based on a blackboard architecture. The rapid prototype simulation capability is provided through an object-oriented modeling environment. It is shown how both simulation and blackboard technologies are used collectively to rapidly gain insight into a tenacious problem. A specific example will be discussed where this approach was used to evolve the logic of a mission controller for an autonomous underwater vehicle.

关键词： Military engineering

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FULL-WAVE SOLUTION OF DIELECTRIC LOADED WAVE-GUIDES AND SHIELDED MICROSTRIPS UTILIZING FINITE-DIFFERENCE AND THE CONJUGATE-GRADIENT METHOD

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INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE computer-AIDED engineering 1991年第4期1卷 346-357页

作者： NARAYANAN, V MANELA, M LADE, RK SARKAR, TK Department of Electrical and Computer Engineering Syracuse University Syracuse New York 13244-1240 Viswanathan Narayanan was born in Bangalore India on December 14 1965. He received the BE degree in Electronics and Communications from B.M.S. College of Engineering Bangalore in 1988. He joined the Department of Electrical Engineering at Syracuse University for his graduate studies in 1989 where he is currently a research assistant. His research interests are in microwave measurements numerical electromagnetics and signal processing. Biographies and photos are not available for M. Manela and R. K. Lade. Tapan K. Sarkar (Sf69-M'76-SM'X1) was born in Calcutta. India on August 2 1948. He received the BTech degree from the Indian Institute of Technology Kharagpur India in 1969 the MScE degree from the University of New Brunswick Fredericton Canada in 1971. and the MS and PhD degrees from Syracuse University. Syracuse NY in 1975. From 1975-1976 he was with the TACO Division of the General Instruments Corporation. He was with the Rochester Institute of Technology (Rochester NY) from 1976-1985. He was a Research Fellow at the Gordon Mckay Laboratory Harvard University Cambridge MA from 1977 to 1978. He is now a Professor in the Department of Electrical and Computer Engineering Syracuse University. His current research interests deal with numerical solutions of operator equations arising in electromagnetics and signal processing with application to system design. He obtained one of the “ best solution” awards in May 1977 at the Rome Air Development Center (RADC) Spectral Estimation Workshop. He has authored or coauthored more than 154 journal articles and conference papers and has written chapters in eight books. Dr. Sarkar is a registered professional engineer in the state of New York. He received the Best Paper Award of the IEEE Transactions on Electromagnetic Compatibility in 1979. He was an Associate Editor for feature articles of the lEEE Antennas arid Propagation Sociefy Newsletter and was

Dynamic analysis of waveguide structures containing dielectric and metal strips is presented. The analysis utilizes a finite difference frequency domain procedure to reduce the problem to a symmetric matrix eigenvalue problem. Since the matrix is also sparse, the eigenvalue problem can be solved quickly and efficiently using the conjugate gradient method resulting in considerable savings in computer storage and time. Comparison is made with the analytical solution for the loaded dielectric waveguide case. For the microstrip case, we get both waveguide modes and quasi-TEM modes. The quasi-TEM modes in the limit of zero frequency are checked with the static analysis which also uses finite difference. Some of the quasi-TEM modes are spurious. This article describes their origin and discusses how to eliminate them. Numerical results are presented to illustrate the principles.

关键词： Waveguides

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New stationary techniques for the analysis and display of speech transients

New stationary techniques for the analysis and display of sp...

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International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： L. Atlas W. Koolman P. Loughlin R. Cole Interactive Systems Design Labaratorys Seattle WA USA Dept. of Electr. Eng. Washington Univ. Seattle WA USA Department of Computer Science and Engineering Oregon Graduate Institute of Science and Technology Beaverton OR USA

A nonstationary analysis technique is applied to speech, with encouraging results. This technique makes use of a generalized time-frequency representation (GTFR) which uses a kernel that allows finite-time support while suppressing interference terms. This kernel has a cone shape in the (t, tau ) plane, where t is time of a signal and tau is an autocorrelationlike lag. The processing thus allows time and frequency resolution equivalent to the Wigner distribution but does not have significant interference terms. It is shown that the effect of this distribution on the long-term (1.5-s) display of speech is a visible enhancement of formant tracks. Potentially more important shorter-term (30-ms or less) advantages are illustrated and quantified as more accurate locations of bursts in the time-frequency distribution. It is shown that the GTFR technique offers a representation which is less sensitive to threshold settings and is thus more robust.< >

关键词： Speech analysis Displays Time frequency analysis Kernel Interference suppression Shape Autocorrelation Signal resolution Speech enhancement Robustness

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SHIP SERVICE ELECTRICAL systems - DESIGNING FOR SURVIVABILITY

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 32-36页

作者： CERMINARA, J KOTACKA, RO John Cerminara:is a principal engineer with Westinghouse Machinery Technology Division Electrical Systems Department. He holds a B.S. degree in electrical engineering from the University of Pittsburgh. He is a registered professional engineer and a member of IEEE ASNE and the Ship Steering Group of the Combat Survivability Division of ADPA. Mr. Cerminara has had over 30 years of multidiscipline experience ranging from engineering and construction in heavy industry to standards and publications. Past assignments include DOE/ NASA wind turbine project manager for Westinghouse and task leader of MTD electrical systems. Most recent assignments have included hull mechanical and electrical (HM&E) distributive system survivability analyses of the LSD-41 mobility mission area and application and validation of NavSea computer-aided design of Survivable Distributive System (CADSDiS) Program. Rolf O. Kotacka:is presently a ship systems engineer in the Ship Systems Engineering Branch of the Naval Sea Systems Command Engineering Directorate where his primary responsibility is ship system survivability. He is a 1977 graduate of SUNY Maritime College where he received his bachelor of engineering degree in marine electrical engineering as well as a U.S. Coast Guard Third Assistant Engineer License and a commission in the U. S. Naval Reserve. Upon graduation Mr. Kotacka was employed by Charleston Naval Shipyard as a field engineer until 1981 where he gained his background in surface ship HM&E systems and equipment. He then transferred to the Supervisor of Shipbuilding Conversion and Repair Groton where he served as a senior electrical engineer monitoring the design and construction of Trident and 688 class submarines and received the Meritorious Unit Citation. Prior to his present position Mr. Kotacka was the life cycle manager for diesel generator sets in the Naval Sea Systems Command's Generators Branch. He has coauthored several papers dealing with power generation for ASE and SNAME. Mr. Kotacka is also a lieutena

This paper highlights the survivability concerns in the design of ship service power systems. The paper gives a brief description of what constitutes a typical ship service electric power system and concentrates on electric power generation and associated controls. Established survivability design principles and guidelines are highlighted and the application of those guidelines are discussed. General Specifications (Gen Specs) for Ships of the U.S. Navy are cited as the cornerstone for design. Specific design criteria are cited as well as the rationale associated with the survivability design guidelines pertaining to power generation and distribution. The application of these survivability design guidelines plus the use of the deactivation diagram/damage tolerance analysis cited in the Gen Spec section 072e will enhance overall design and help ensure survivable electric power systems for surface combatants.

关键词： Warships

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computer-SYSTEM ARCHITECTURE CONCEPTS FOR FUTURE COMBAT systems

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NAVAL ENGINEERS JOURNAL 1990年第3期102卷 43-62页

作者： ZITZMAN, LH FALATKO, SM PAPACH, JL Dr. Lewis H. Zitzman:is the group supervisor of the Advanced Systems Design Group Fleet Systems Department The Johns Hopkins University Applied Physics Laboratory (JHU/APL). He has been employed at JHU/APL since 1972 performing applied research in computer science and in investigating and applying advanced computer technologies to Navy shipboard systems. He is currently chairman of Aegis Computer Architecture Data Bus and Fiber Optics Working Group from which many concepts for this paper were generated. Dr. Zitzman received his B.S. degree in physics from Brigham Young University in 1963 and his M.S. and Ph.D. degrees in physics from the University of Illinois in 1967 and 1972 respectively. Stephen M. Falatko:was a senior engineering analyst in the Combat Systems Engineering Department Comptek Research Incorporated for the majority of this effort. He is currently employed at ManTech Services Corporation. During his eight-year career first at The Johns Hopkins University Applied Physics Laboratory and currently with ManTech Mr. Falatko's work has centered around the development of requirements and specifications for future Navy systems and the application of advanced technology to Navy command and control systems. He is a member of both the Computer Architecture Fiber Optics and Data Bus Working Group and the Aegis Fiber Optics Working Group. Mr. Falatko received his B.S. degree in aerospace engineering with high distinction from the University of Virginia in 1982 and his M.S. degree in applied physics from The Johns Hopkins University in 1985. Mr. Falatko is a member of Tau Beta Pi Sigma Gamma Tau the American Society of Naval Engineers and the U.S. Naval Institute. Janet L. Papach:is a section leader and senior engineering analyst in the Combat Systems Engineering Department Comptek Research Incorporated. She has ten years' experience as an analyst supporting NavSea Spa War and the U.S. Department of State. She currently participates in working group efforts under Aegis Combat System Doctrin

This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis computer systems architecture, expanding that architecture while preserving, and adhering to, the Aegis fundamental principle of thorough systems engineering, dedicated to maintaining a well integrated, highly reliable, and easily operable combat system. The implementation of these proposed computer systems concepts in a coherent architecture would support the future battle force capable combat system and allow the expansion necessary to accommodate evolutionary changes in both the threat environment and the technology then available to effectively counter that threat. Changes to the current Aegis computer architecture must be carefully and effectively managed such that the fleet will retain its combat readiness capability at all times. This paper describes a possible transition approach for evolving the current Aegis computer architecture to a general architecture for the future. The proposed computer systems architecture concepts encompass the use of combinations of physically distributed, microprocessor-based computers, collocated with the equipment they support or embedded within the equipment itself. They draw heavily on widely used and available industry standards, including instruction set architectures (ISAs), backplane busses, microprocessors, computer programming languages and development environments, and local area networks (LANs). In this proposal, LANs, based on fiber optics, will provide the interconnection to support system expandability, redundancy, and higher data throughput rates. A system of cross connected LANs will support a high level of combat system integration, spanning the major warfare areas, and will facilitate the coordination and development of a coherent multi-warfare tactical picture supporting the future combatant command st

关键词： computer Architecture

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FLAMMABILITY AND TOXICITY OF COMPOSITE-MATERIALS FOR MARINE VEHICLES

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 45-54页

作者： SEVART, JL GRIFFIN, OH GURDAL, Z WARNER, GA Jeffrey L. Sevart:is a native of Kansas and a 1985 graduate of Kansas State University with a B.S. in mechanical engineering (magna cum laude). After working as a stress analysis engineer at Boeing Military Airplane Company in Wichita Kans. he attended Virginia Polytechnic Institute and State University and received an M.S. in engineering mechanics in February 1988. He currently resides in Akron Ohio working as a research engineer in tire composites research at The Goodyear Tire and Rubber Company. O. Hayden Griffin Jr.:received his B.S. and M.S. in mechanical engineering from Texas Tech University in 1970 and 1971 respectively. He received his Ph.D. in engineering mechanics from Virginia Polytechnic Institute and State University in 1980. Prior to joining the faculty of Virginia Polytechnic Institute and State University as associate professor of engineering science and mechanics in September 1985 he was employed at the U.S. Naval Surface Warfare Center (Dahlgren Virginia) BF Goodrich Tire Group (Akron Ohio) the Bendix Advanced Technology Center (Columbia Maryland) and the Johns Hopkins University Applied Physics Laboratory (Laurel Maryland). He is currently an associate director of the Virginia Institute for Material Systems. He is a registered professional engineer in Virginia and is a member of the American Society of Mechanical Engineers and the American Society for Composites. Zafer Gürdal:received his M.S. in mechanical and aerospace engineering from Illinois Institute of Technology in 1981 and his Ph.D. in aerospace engineering from Virginia Polytechnic Institute and State University in 1985. He worked as a research associate in the Aerospace and Ocean Engineering Department at Virginia Tech before joining the Engineering Science and Mechanics Department as an assistant professor in September 1985. Professor Gürdal's research interests include: composite structures failure mechanics of composites structural optimization and damage tolerant design. He is a member of the American Institute

Characteristics of both thermoplastic and thermoset composite materials as they pertain to marine vehicle applications are discussed. Comparison of various material selection factors such as strength, damage and moisture resistance, and flammability and toxicity as well as cost and availability of thermoset and thermoplastic composite materials are presented. Methods for testing and reducing the flammability and toxicity are discussed. Many commercially available composite systems are reported to provide favorable characteristics for marine applications. Although there seems to be a need for improved production technology for thermoplastics, they present potential advantages in physical properties over thermoset composites.

关键词： Composite Materials

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ELECTRICALLY INDUCED TRANSMISSIVITY MODULATION IN POLYMERIC THIN-FILM FABRY-PEROT ETALONS

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APPLIED OPTICS 1989年第20期28卷 4442-4445页

作者： ELDERING, CA KOWEL, ST KNOESEN, A []The authors are with University of California Davis Department of Electrical Engineering Computer Science Organized Research Program on Polymeric Ultrathin Film Systems Davis California 95616

We report the observation of electrically induced changes in transmissivity in Fabry-Perot devices consisting of spin-cast azo-dye/polymer films deposited between gold mirrors. In poled samples the observed modulation shows a linear dependence on the applied modulating voltage. The ratio of the transmissivity modulation observed using incident transverse magnetic polarization to that observed using transverse electric polarization is used to demonstrate that the electrooptic effect dominates the modulation. This is, to our knowledge, the first reported use of a polymeric thin film linear electrooptic material in a Fabry-Perot structure and demonstrates the use of etalons to enhance electrooptic effects in very thin films.

关键词： Electrooptical effects Electrooptical modulators Materials processing Refractive index Thin film applications Thin films

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Biological image understanding

Biological image understanding

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Medical Imaging III: Image Processing 1989

作者： Dunn, Stanley M. Department of Biomedical Engineering Rutgers University P.O. Box 909 PiscatawayNJ08855-0909 United States Laboratory for Computer Science Research Rutgers University Diagnostics Systems Program New Jersey Dental School NewarkNJ United States

The primary goal of any computer vision system is to construct scene descriptions similar to those formed by the human visual system. Biological image understanding is the automatic processing and interpretation of imagery of natural structures. The key constraint is the absence of explicit models of the objects anticipated to be in the scene. A clinician interprets imagery using principles of physiology and the image acquisition process. He learns to construct explicit models to recognize patterns from these principles, but is also able to infer an interpretation of an unknown structure from examples and physiology. Our overall goal is to develop a computer vision system to be used to interpret imagery of biological data using these principles. In this paper we present a paradigm for constructing image understanding systems designed to process natural images and present some applications of the system to hematology and radiography. The first step of our general approach is data acquisition. The second step is to find intrinsic properties at each pixel. The third step is to group pixels together to for homogeneous regions using the intrinsic properties. The final step is object recognition, where object type and location are determined from the quantitative features of the homogeneous regions. We shall outline the algorithms and data structures used at each step in the process, and their implementation. We shall describe in detail a key feature of this paradigm - forming homogeneous regions by geometry guided segmentation. The fact that classical algorithms do not always yield correct results led us to an algorithm that uses structural information and intensity values to group homogeneous regions. We shall illustrate this problem and the solution, as well as preliminary results of the application of the image understanding system. © 1989 SPIE. All rights reserved.

关键词： Physiology

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