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International Conference on Telecommunications in Modern Satellite, Cable and Broadcasting Service (TELSIKS)

作者： S.N. Yanushkevich V.P. Shmerko R.S. Stankovic P. Dziurzanski D.V. Popel Department of Computer Aided Design Systems Technical University of Szczecin Poland Department of Computer Science University of Nis Yugoslavia Department of Computer Science State University of Informatics and Radioelectronics of Belarus Minsk Belarus

We present a new entropy based method for minimization of sum-of-product (SOP) expressions of switching functions. Unlike the recent results which utilize binary decision trees (DTs), we study the minimization procedure as a heuristic search based on information measures on the free pseudo ternary DTs. The main contribution of this paper is an experimental justification of the entropy based method that yields the extreme improvements compared to some recent results on application of information theory methods for SOP minimization of switching functions. In most cases, we obtained that the quality of minimization with our minimizer InfoMin-2 is the same as that produced by ESPRESSO package, but is often performed faster.

关键词： Entropy Minimization methods Information theory computer science Decision trees Logic functions Packaging design automation Logic testing design engineering

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Information theoretical approach to minimization of AND/EXOR expressions of switching functions

Information theoretical approach to minimization of AND/EXOR...

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International Conference on Telecommunications in Modern Satellite, Cable and Broadcasting Service (TELSIKS)

作者： V. Shmerko D. Popel R.S. Stankovic V. Cheushev S. Yanushkevich Department of Computer Aided Design Systems Technical University of Szczecin Poland Department of Computer Science State University of Informatics and Radioelectronics of Belarus Minsk Belarus Department of Computer Science University of Nis Yugoslavia Department of Programming Technologies State University Minsk Belarus

In modern circuit design, the Shannon decomposition of switching functions is widely used. On the other hand, in information theory of telecommunication, the Shannon entropy used as a measure to represent the information in numerical values, is a key notion. In this paper, we relate these two concepts, belonging to different areas, into an approach to the minimisation of exclusive-or sum-of-products (AND/EXOR) expressions for switching functions. The Shannon decomposition, and the closely related Davio decomposition for AND/EXOR expressions are interpreted in terms of basic concepts in the information theory. Thanks to that, we have proposed an entropy based strategy for minimization of AND/EXOR expressions. We have provided a comparison and an experimental verification of this strategy with some known heuristic minimization strategies using benchmarks. In some cases, our program Info-EXOR produces extremely better results. Moreover, the information theory interpretation of classical decomposition of switching functions offers a new point of view to the existing design styles.

关键词： Minimization Entropy Information theory Switching circuits Telecommunication switching Circuit synthesis Data structures Boolean functions Electronic mail Logic design

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A new approach to synthesis of matching networks and equalizers for RF and microwave solid-state circuits

A new approach to synthesis of matching networks and equaliz...

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IEEE International Symposium on Circuits and systems (ISCAS)

作者： L.I. Babak Department of Computer-Aided Design Systems Tomsk슠State Academy of Control Systems and Radioelectronics Tomsk Russia

A new synthesis method which takes into account the arbitrary constraints on the input impedance of lossless matching network or equalizer is presented. The method is particularly suitable for designing matching networks and equalizers used in various RF and microwave solid-state circuits (such as broadband transistor amplifiers, mixers, multipliers, etc.). With this method, e.g., a suppression of higher order harmonics in the output signal, the circuit stability conditions, requirements for the simultaneous set of circuit characteristics, experimental load - pull data, etc., can be considered in the network synthesis.

关键词： Network synthesis Equalizers Circuit synthesis Impedance Solid state circuit design Radio frequency Microwave theory and techniques Solid state circuits Microwave transistors Microwave amplifiers

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Developing a prototype concurrent design tool for composite topside structures

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NAVAL ENGINEERS JOURNAL 1997年第3期109卷 279-290页

作者： Dirlik, S Hambric, S Azarm, S Marquardt, M Hellman, A Bartlett, S Castelli, V Steve Dirlik:began his career at the Naval Surface Warfare Center Carderock Division in 1981 as an aerospace engineer co-op student. He completed his bachelor of science degree in aeropace and ocean engineering from Virginia Polytechnic Institute and State University in 1985 and his master of science degree in aerospace engineering from the University of Maryland in 1990. Mr. Dirlik recently completed a master of science program in applied physics at The Johns Hopins University and currently works in the Radar Cross Section and Target Physics Branch of the Signatures Directorate at the Naval Surface Warfare Center Corderoke Division. He has worked on Navy low observable programs since 1990. Stephen Hambric:is a research associate at the Applied Research Laboratory at The Pennsylvania State University. He received his B. S. and M.S. degree in mechanical engineering from Virginia Polytechnic Institute and State University and his D. Sc. in mechnical engineering from the George Washington University. He has worked on several computer aided multidiscikplinary design and optimization projects over the years including an automated propeller design system and a structural acoustic optimization capability. Dr. Shpour Azarm:is currently working as an associate professor with the Design and Manufacturing Group of the Department of Mechanical Engineering at the University of maryland at College Park. Dr Azarm's expertise is in the areas of optimization-based designed and concurrent design and optimization of multidisciplinary systems. He was a consultant at Black & Decker Corporation (summer 1996) and worked as a Navy senior summer faculty fellow (summer 1995) and a NASA summer faculty fellow (summer 1994). He was a visiting scientist at NASA Langley Research Center for Multidisciplinary Analysis and Applied Structural Optimzatiom at the University of Siegen in Germany (spring 1992) and the Design Institute of the Technical University of Denmark (summer 1990). Dr Azarm was an associate technical editor of the ASME Jour

A prototype concurrent engineering tool has been developed for the preliminary design of composite topside structures for modern navy warships. This tool, named GELS for the Concurrent Engineering of Layered Structures, provides designers with an immediate assessment of the impacts of their decisions on several disciplines which are important to the performance of a modern naval topside structure, including electromagnetic interference effects (EMI), radar cross section (RCS), structural integrity, cost, and weight. Preliminary analysis modules in each of these disciplines are integrated to operate from a common set of design variables and a common materials database. Performance in each discipline and an overall fitness function for the concept are then evaluated. A graphical user interface (GUI) is used to define requirements and to display the results from the technical analysis modules. Optimization techniques, including feasible sequential quadratic programming (FSQP) and exhaustive search are used to modify the design variables to satisfy all requirements simultaneously. The development of this tool, the technical modules, and their integration are discussed noting the decisions and compromises required to develop and integrate the modules into a prototype conceptual design tool.

关键词： Warships

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Influence of human engineering on manning levels and human performance on ships

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NAVAL ENGINEERS JOURNAL 1997年第5期109卷 67-76页

作者： Anderson, DE Oberman, FR Malone, TB Baker, CC David E. Anderson:has a bachelor of science degree in environmental engineering from Florida Technological University and a master's degree in environmental engineering from the University of Central Florida. He is a graduate of the Naval Sea Systems Command's Engineer-In-Training (EIT) Program. Mr. Anderson was instrumental in introducing the collective protection system (CPS) in the U.S. Navy developing the initial forward-fit package for the USS Gunston Hall and the engineering change proposal (ECP) for the USS Wasp. In 1990 he joined the Human Systems Integration (HSI) Division (SEA 55W5) where he was task leader for auxiliary ships. He is currently the HSI manager for the future technology variant of the SeaLift ship and the future carrier. Association of Scientists and Engineers 33rdAnnual Technical Symposium 26 April 1996. Fred R. Oberman:has B.A. and M.A. degrees from the University of Chicago and Loyola University (experimental psychology) and an M.S. degree in industrial engineering and operations research from Virginia Polytechnic Institute (VPI). He has more than 30 years experience in HSI management planning research analysis design and testing in government and private sector positions. He is currently responsible for NavSea HSI generic research and tool development efforts. He is responsible for Human Engineering Specifications and Standards (Commercial Hypertext) and is the NavSea 03D7 representative on HSI in Performance Specifications and for integration of HSI within Integrated Logistic Support (ILS). He has served as DoD HSI SubTAG chair and member of the Simulation and Modeling Test and Evaluation Display and Control Systems Human Computer Interaction Specifications and Standards and Systems Design Sub Tags as a member of the Society of Naval Architects and Marine Engineers (SNAME) Systems Safety Panel and a member of NATO RSG 14 on man-machine analysis. Thomas B. Malone: CHFEP received a Ph.D. in experimental psychology from Fordham University in 1964. He is president of Carlow

The objectives of Human Engineering (HE) are generally viewed as increasing human performance, reducing human error, enhancing personnel and equipment safety, and reducing training and related personnel costs. There are other benefits that are thoroughly consistent with the direction of the Navy of the future, chief among these is reduction of required numbers of personnel to operate and maintain Navy ships. The Naval Research Advisory Committee (NRAC) report on Man-Machine Technology in the Navy estimated that one of the benefits from increased application of man-machine technology to Navy ship design is personnel reduction as well as improving system availability, effectiveness, and safety The objective of this paper is to discuss aspects of the human engineering design of ships and systems that affect manning requirements, and impact human-performance and safety The paper will also discuss how the application of human engineering leads to improved performance, and crew safety, and reduced workload, all of which influence manning levels. Finally, the paper presents a discussion of tools and case studies of good human engineering design practices which reduce manning.

关键词： Human engineering

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PARALLEL AND DISTRIBUTED TLM COMPUTATION WITH SIGNAL-PROCESSING FOR ELECTROMAGNETIC-FIELD modeling

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INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS 1995年第3-4期8卷 169-185页

作者： SO, PPM ESWARAPPA, C HOEFER, WJR NSERC/MPR Teltech Research Chair in RF Engineering Department of Electrical and Computer Engineering University of Victoria Victoria British Columbia V8W 3P6 Canada Poman So received his B.Sc. degree in computer science and physics from the University of Toronto Toronto Onatario Canada in 1985. He obtained his B.A. Sc. and M.A.Sc. degrees in electrical engineering (summa cum laude) from the University of Ottawa Ottawa Ontario Canada in 1987 and 1989 respectively. Mr So was a research engineer in the University of Ottawa from January 1989 to October 1991 his research interests included CAD techniques of microwave circuits and numerical methods for electromagnetic wave modelling. He specialized in the development of electromagnetic engineering CAD software and successfully implemented a number of electromagnetic wave simulators based on the two-dimensional and three-dimensional transmission-line matrix methods. From August 1990 to February 1991 he accompanied Professor W. J. R. Hoefer to Rome Italy and Sophia Antiopolas France. During that time he implemented a parallel version of the 3D-TLM simulator for the CM-2 Connection Machine using C-Star and X Windows Library. He is a research engineer and a Ph.D. student at the University of Victoria Victoria British Columbia Canada. He ported the 2D- and 3D-TLM simulators to DECmpp 1200 massively parallel computer using MPL C and C++. He also combined OSA90/hope a commercially available microwave CAD program with a 2D-TLM simulation module for geometry optimization using the Datapipe technique of OSA90/hope. Recently he has developed a distributed client-server computing technique for the TLM method this technique could accelerate the TLM simulation by more than an order of magnitude. Channabasappa Eswarappa received the M.Tech. degree in electrical engineering from the Indian Institute of Technology Kanpur India in 1983 and Ph. D. degree from the University of Ottawa Canada in 1990. He worked as an Assistant Executive Engineer and later as

This paper describes the implementation of transmission-line matrix (TLM) method algorithms on a massively parallel computer (DECmpp 12000), the technique of distributed computing in the UNIX environment, and the combination of TLM analysis with Prony's method as well as with autoregressive moving average (ARMA) digital signal processing for electromagnetic field modelling. By combining these advanced computation techniques, typical electromagnetic field modelling of microwave structures by TLM analysis can be accelerated by a few orders of magnitude.

关键词： Mathematical models

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CONCURRENT LARGE-SIGNAL SIMULATION OF AN ACTIVE MICROSTRIP ANTENNA

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INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS 1995年第1期8卷 3-12页

作者： MCDOWALL, DS FUSCO, VF High Frequency Electronics Laboratory. Department of Electrical and Electronic Engineering The Queen's University of Belfast Ashby Building Stranmillis Road Belfast BT9 5AH U.K. D. Stewart McDowall was born in Dublin Republic of Ireland in 1967. He received the M. Eng. degree in Electrical and Electronic Engineering from the Queen's University of Belfast in 1990. In the same year he was presented with a Distinction Award from the Departmnet of Education of Northern Ireland and he is currently pursuing his Ph.D. in the Microwave Research Group at Q.U.B. His principal research area is the electromagnetic field mapping of microwave systems using concurrent programming. He is an Associate Member of the Institute of Electrical Engineers. Vincent F. Fusco was educated at the Queens's University of Belfast where he obtained the degree of Ph.D. in 1982. He has worked as a research engineer on short-range radar and radio telemetry systems. Currently he is a reader in Microwave Communications in the School of Electrical engineering and Computer Science the Queen's University of Belfast. His current research interests include non-linear microwave circuit simulatino and concurrent programming techniques for electromagnetic field problems with particular emphasis on EMC applications. He has published numerous research papers in these areas. He is the author of the bookMicrowave Circuits Analysis and Computer Aided Design Prentice-Hall 1987. Dr Fusco is a Chartered Electrical Engineer and a Member of the Institute of Electrical Engineers.

This paper details the use of a circuit-based EM modelling technique combined with a harmonic balance simulator used to model the radiation from the microstrip bodies comprising an active antenna circuit. The modelling approach adopted for the planar bodies in the circuit will be shown to allow the use of concurrent algorithms in order to reduce overall computational time.

关键词： Microstrip antennas

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USING VIRTUAL ENVIRONMENTS IN THE design OF SHIPS

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NAVAL ENGINEERS JOURNAL 1994年第3期106卷 91-106页

作者： JONS, OP RYAN, JC JONES, GW Otto P. Jons:received a Diplom Ing. in shipbuilding from the Technical University of Hanover W. Germany and an MS in naval architecture and marine engineering from MIT. He then joined Litton Ship Systems where he was responsible for the preliminary design of the DD-963 hull structure and then for ship system integration as manager LHA ship systems engineering department. From 1972 to 1974 he was the principal research scientist at Hydronautics. In 1974 as technical director he helped establish the Crystal City office of Designers and Planners. Mr. Jons was one of the co-founders of Advanced Marine Enterprises Inc. in 1976 where he serves as corporate vice president engineering. J. Christopher Ryan:earned his bachelors and masters degrees in naval architecture from Webb Institute and MIT respectively. He spent three years at the advanced marine technology division of Litton Industries working on the DD-963 class ship design and related computer aided design projects. He subsequently went to the Navy Department concentrating on early stage design of surface combatants for twelve years including work on the FFG-7 Sea Control Ship CSGN and CVV aircraft carrier projects. He then shifted focus and became the Technical Director for the Computer Supported Design Program in NavSea for five years. Mr. Ryan has served in several supervisory positions within the Ship Design Group in NavSea since that time. He is currently the director of the future ship concepts division. Gary W. Jones:graduated from the University of Tennessee in 1971 with a BS in mechanical engineering and followed up with graduate work at George Washington University and the University of Maryland. Mr. Jones was with the Naval Sea Systems Command from 1971 until 1988 where he was a naval architect in the submarine section of the hull form design division. In 1988 he was detailed to the Defense Advanced Research Projects Agency (DARPA) where he became the program manager for the advanced submarine technology program's hydrodynamic hydroac

A major contributor to the expense and length of time to design, build, and test new systems has been the need to build and test hardware prototypes to determine their effectiveness in meeting operational requirements. Recent and dramatic advances in computer simulation technologies hold forth the promise of revolutionizing design and acquisition strategies by providing the means to validate end users' requirements prior to hardware construction. By designing and operationally testing virtual prototypes in a virtual environment, these technologies will soon offer naval architects the ability to build and launch ships in computer-based cyberspace in lieu of the shipbuilder's ways. The authors of this paper provide the background for these developments, explore the significance and ramifications of these technologies to the current process of ship and system design, outline challenges lying ahead, and present their vision and recommendations for future development.

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THE PARALLEL COMPUTATION OF SOLUTIONS TO ELECTROSTATIC PROBLEMS USING MULTIGRID TECHNIQUES

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INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS 1994年第1期7卷 69-74页

作者： WARING, LC ROONEY, N STEWART, A FUSCO, VF Department of Computer Science The Queen's University of Belfast Belfast BT7 1NN Northern Ireland U.K. Lionel C. Waring obtained his B.Sc. (1967) and his Ph.D. (1971) in Electrical Engineering at the Queen's University of Belfast. A short period with Short Bros. and Harland was followed by an appointment in 1972 to Queen's University Chemistry Department where he was in charge of the Mass Spectrometry and Nuclear Magnetic Resonance facilities. In 1987 he was appointed Senior Research Officer in the Department of Computer Science Q.U.B. and in 1993 to a lectureship in the same Department. Department of Electrical and Electronic Engineering. Vincent F. Fusco was educated at the Queens University of Belfast where he obtained the degree of Ph.D. He worked as a research engineer on short-range radar and radio telemetry systems from 1982 to 1984. He is currently Reader in Microwave Communications in the School of Electrical Engineering and Computer Science The Queens University of Belfast. His current research interests include non-linear microwave circuit simulation and concurrent techniques for electromagnetic field problems. He has published a number of research papers in these areas and is the author of Microwave Circuits Analysis and Computer Aided Design Prentice-Hall 1987. Dr Fusco is a Chartered Electrical Engineer and a Member of the Institution of Electrical Engineers.

The application of multigrid techniques to the computation of the static solutions of electromagnetic field problems governed by Laplace's equation is described. This technique is compared with the conventional successive over-relaxation (SOR) method for solving finite difference problems. In contrast to SOR, the number of iterations of multigrid needed to achieve convergence is largely independent of the grid size. It is shown that the relative performance of multigrid is excellent on large grids where the number of iterations of SOR needed to achieve convergence becomes prohibitively large. The technique is illustrated by applying a parallel implementation of multigrid to find a quasistatic solution of a boxed microstrip problem.

关键词： Electrostatics

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Fasciolosis in cattle in Louisiana. II. Development of a system to use soil maps in a geographic information system to estimate disease risk on Louisiana coastal marsh rangeland

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Veterinary Parasitology 1993年第1-2期47卷 51-65页

作者： Zukowski, Stanley H. Wayne Wilkerson, G. Malone Jr., John B. Department of Veterinary Microbiology and Parasitology School of Veterinary Medicine Louisiana State University Baton Rouge LA 70803 United States Computer-Aided Design and Geographic Information Systems Laboratory Louisiana State University Baton Rouge LA 70803 United States

A geographic information system (GIS) model of habitat for Lymnaea bulimoides, the snail intermediate host of Fasciola hepatica and the rumen fluke, Calicophoron microbothrioides, on the Chenier Plain of southwest Louisiana was revised to incorporate broad (greater than 100 m) chenier (relict beaches) along with adjacent marsh and transitional soils associated with spatial distribution of L. bulimoides habitat. The proportion of farmland comprised of soils of the GIS model coincided with actual habitat from a previous survey with a sensitivity of 91.3% and a specificity of 80.1%, and regressed significantly against the proportion of farmland comprised of L. bulimoides habitat (n = 12, P = 0.01, r² = 0.50, slope = 0.015). A soil model index was calculated to incorporate (1) the proportion of farmland comprised of soils of the GIS model and (2) stocking rate. Fluke egg shedding indices (mean egg count multiplied by prevalence) were calculated for each fluke species on nine farms at four sampling times over a 2-year period. The maximum egg shedding indices for each farm, taken to indicate potential fluke transmission intensity, were correlated for the two fluke species on herds not recently treated for fasciolosis (n = 9, P = 0.004, r² = 0.72, slope = 0.2), although at no one sampling period were shedding indices of the two fluke species significantly correlated. Egg shedding of C. microbothrioides by cattle correlated with the proportion of farmland comprised of soils included in the GIS model (n = 9, Spearman's rank coefficient was 0.7, P = 0.05). We conclude that (1) the maximum of several observations of the C. microbothrioides egg shedding index may be useful as a surrogate for F. hepatica in estimating risk from snail habitat on a farm when regular flukicide treatment interferes with F. hepatica egg shedding, and (2) the GIS model may estimate site-specific differences in fasciolosis risk to cattle operations in the Chenier Plain based on th

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