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An approach to the direct analysis of transient stability

european Transactions on electrical Power 1993年第3期3卷 241-248页

作者： Djukanovic, M.b. Sobajic, D.J. Pao, Y.‐H. Miodrag B. Djukanovic (1959) received his B.S. M.Sc. and Ph.D. degrees in Electrical Engineering from the University of Belgrade/Yugoslavia in 1982 1985 and 1992 respectively specializing in electric power systems. In 1984 he joined the Electrical Engineering Institute “Nikola Tesla” in Belgrade where he was working on the scientific studies in the field of power systems planning operation and control. In 1985 and 1990 he was appointed as a research scholar at the Royal Institute of Technology Stockholm and Case Western Reserve University Cleveland Ohio. His major in- terests are in the area of power system analysis steady-state and dynamic security and application of neural networks in electric power systems. (Electrical Engineering Institute “Nicola Tesla” ul. Koste Glavinica 8A YU-11000 Belgrad T +3811/2351-619 Fax + 3811/2351-823) Dejan J. Sobajic (1949) received the B.S.E.E. and the M.S.E.E. degrees from the University of Belgrade/Yugoslavia in 1972 and 1976 respectively and the Ph.D. degree from Case Western Reserve University Cleveland Ohio in 1988. At present he is with the Department of Electrical Engineering and Applied Physics Case Western Reserve University Cleveland. He is also the Engineering Manager of A1 WARE Inc. Cleveland. His current research interests include power system operation and control neuralnet systems and adaptive control. He is a member of the IEEE Task Force on Neural-Network Applications in Power Systems and of the IEEE Intelligent Controls Committee. He is the Chairman of the International Neural-Networks Society Special Interest Group on Power Engineering. (Case Western Reserve University Department of Electrial Engineering and Computer Sciences Glennan Building Ohio 44 106 USA T + 1216/421-2380 Fax +1216/368-8776) Yoh-Han Pao (1922) has been a Professor of Electrical Engineering and Computer Science at Case Westem Reserve University (CWRU) Cleveland Ohio since 1967. He has served as chairman of the University's Electrical Engineering Department

The Transient energy Function (TeF) method has b.en intensely investigated over the last decade as a reliab.e and accurate tool for transient stability assessment of multimachine power systems. In this paper we propose the Potential energy boundary Surface (PebS) based method for direct analysis of transient stability. The critical value of transient energy and the Critical Clearing Time (Tb>CCTb>) are evaluated without the need for successive calculation and memorization of the system kinetic and potential energy values along the sustained fault trajectory. The method is used for determination of output features in the training phase of the neural‐net based transient security assessment. The proposed approach is tested on the well‐known ten‐generator New england test system demonstrating the validity and accuracy of obtained results. Copyright © 1993 John Wiley & Sons, Ltd.

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Interactive tools for signal processing education. The signal processing instructional facility (SPIF lab) at Washington State University

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computer Applications in engineering education 1993年第6期1卷 517-517页

作者： bamberger, R.H. Signal Processing Instructional Facility School of Electrical Engineering and Computer Science Washington State University Pullman WA 99164-2752 Dr. Roberto H. Bamberger:was born on January 30 1965 in Buenos Aires Argentina. He received his B.E.E and PhD from the Georgia Institute of Technology in 1986 and 1990 respectively. Currently Dr. Bamberger is an assistant professor in the School of Electrical Engineering and Computer Science at Washington State University. Dr. Bamberger's research program is focused on the design implementation and application of multidimensional multirate filter banks subband image and video compression analysis of nonstationary data and application of digital signal processing techniques in the design of analog and mixed-mode integrated circuits. Dr. Bamberger is the founder and director of the Signal Processing Instructional Facility (SPIF Lab) at Washington State University. The SPIF Lab features interactive multimedia-based tools for teaching concepts related to linear systems theory. Dr. Bamberger is active in developing multimedia-based instructional laboratories for a variety of other topics as well. In addition to his teaching and research programs Dr. Bamberger is an associate editor for theIEEE Transactions on Signal Processingand a member of the editorial board forComputer Applications in Engineering Education. Dr. Bamberger is also advisor to the WSU Student Branch of the IEEE and assistant director of the WSU Cougar Marching Band. Dr. Bamberger is a member of Phi Eta Sigma Eta Kappa Nu Tau Beta Pi and Kappa Kappa Psi.

The Signal Processing Instructional Facility (SPIF Lab) is an experiment in using in interactive multimedia for teaching concepts related to linear systems theory and signal processing. The goals of the SPIF lab are to augment, enhance, and interconnect sophomore, junior, and senior level courses with the common thread of linear systems and transforms by unifying the experimentation medium. In this fashion, physical phenomenon is returned to the forefront of engineering education. The laboratory features powerful Mathematica Notebooks (a form of hypertext) and interactive applications that use dedicated DSP microprocessors.

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UNCONDITIONAL STAb.e MeTHODS FOR 2ND-ORDeR ORDINARY DIFFeReNTIAL-eQUATIONS

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INTeRNATIONAL JOURNAL OF computer MATHeMATICS 1992年第3-4期41卷 181-188页

作者： GAReY, Le GLADWIN, CJ Division of Mathematics Engineering and Computer Science University of New Brunswick Saint John N.B. E2L 4L5 P.O. Box 5050 Canada

Henrici's concept of conditional stability is considered for second order differential equations. Multi-derivative multi-step methods are used to construct explicitly unconditional stab.e methods of order 2 for a ... 详细信息

关键词： ORDINARY DIFFeReNTIAL eQUATIONS UNCONDITIONAL STAbILITY MULTI-DeRIVATIVe

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COMPARISON OF DOWNHOLe AND SURFACe SAMPLING FOR THe DeTeRMINATION OF VOLATILe ORGANIC-COMPOUNDS (VOCS) IN GROUND-WATeR

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GROUND WATeR MONITORING AND ReMeDIATION 1992年第1期12卷 126-133页

作者： ROSeN, Me PANKOW, JF GIbS, J IMbRIGIOTTA, Te Michael E. Rosen received his B.A. in chemistry from the State University of New York at Binghamton in 1981 and a Ph.D. in environmental science and engineering from the Oregon Graduate Institute in 1988. His research interests include trace environmental analysis of organic compounds. He is now manager of the Voluntary Cleanup Section of the Oregon Department of Environmental Quality (Environmental Cleanup Division 811 S.W. 6th Ave. Portland OR 97204) where he is working to develop streamlined procedures and processes for the investigation and cleanup of hazardous substance sites. James F. Pankow is professor and chairman of the Department of Environmental Science and Engineering at the Oregon Graduate Institute (Oregon Graduate Institute of Science and Technology Department of Environmental Science and Engineering 19600 N.W. von Neumann Dr. Beaverton OR 97006–1999). He received his B.A. in chemistry in 1973 from the State University of New York in Binghamton and his Ph.D. in environmental engineering science from the California Institute of Technology in Pasadena California in 1979. His group is involved in the study of the physical and chemical processes affecting the behavior of organic and inorganic chemicals in the environment. This work includes the development and application of sensitive analytical methods for the determination of trace organic contaminants in ground water systems. Jacob Gibs is an environmental engineer with the U.S. Geological Survey Water Resources Division (810 Bear Tavern Rd. Ste. 207 West Trenton NJ 08628). He received a B.S. in mechanical engineering in 1968 an M.S. in environmental engineering in 1975 and a Ph.D. in environmental engineering in 1983 all from Drexel University Philadelphia Pennsylvania. He is currently project chief of a study on representative sampling of ground water for trace levels of organic compounds. His research interests include evaluating ground water sampling techniques and devices for purgeable organic compounds design of sampling

The relative precision and accuracy of sampling and analysis methods for the determination of trace concentrations of volatile organic compounds (VOCs) in ground water were compared. Samples were collected from a well containing nanogram-per-liter (ng/L) to microgram-per-liter (mu-g/L) levels of VOCs. A Keck helical rotor sub.ersib.e pump was used to collect samples at the surface for analysis by purge and trap (P&T) and for analysis by adsorption/thermal desorption (ATD). Downhole samples were collected by passing water through an ATD cartridge. Although slight spontaneous bubb.e outgassing occurred when the water was brought to the surface, the relative precisions and comparabilities of the surface and downhole methods were generally found to be equivalent from a statistical point of view. A main conclusion of this study is that bringing sample water to the surface for placement in VOC vials (and sub.equent analysis by P&T) can be done reliably under many circumstances. However, care must still be taken to prevent adsorption losses and cross contamination. Samples sub.ect to strong bubb.e outgassing will need to be handled in a special fashion (e.g., by downhole ATD) to minimize volatilization losses. Additionally, the higher sensitivity of the ATD method allows lower detection limits than are possib.e with P&T. For example, several compounds present at the ng/L level could be determined with confidence by ATD, but not by P&T.

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Preface

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Lecture Notes in computer science (including sub.eries Lecture Notes in Artificial Intelligence and Lecture Notes in bioinformatics) 1992年 654 LNCS卷 V-VI页

作者： Nakamura, Akira Nivat, Maurice Saoudi, Ab.ed Wang, Patrick S. P. Inoue, Katsushi Meiji University Faculty of Science Dept. of Information Science Higashimita Tama-ku Kawasaki-shi214 Japan University Paris VII LITP 2 place de Jussieu ParisF-75221 France University Paris XIII Institut Galilée L.I.P.N. Av. J. B. Clement VilletaneuseF-93430 France College of Computer Science Northeastern University 161 Cullinane Hall BostonMA02115 United States Yamaguchi University Dept. of Computer Science and Systems Engineering Ube755 Japan

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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 sub.equent core sleeve withdrawal from adjacent boreholes. Soil samples removed from the Mason jars (in the field) and sleeve segments (in the laboratory) were sub.ected 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 tab.e. 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 ob.ervations, so that replicate barrels or a half-pint Mason jar size should be considered for data supporting vertical transport analyses in the ab.ence 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 valuab.e 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 prob.em 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 prob.em. 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 ob.ect-oriented modeling environment. It is shown how both simulation and blackboard technologies are used collectively to rapidly gain insight into a tenacious prob.em. 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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GeNeRATION OF DISCReTe RANDOM VARIAb.eS ON VeCTOR computerS FOR MONTe CARLO SIMULATIONS

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International Journal of High Speed Computing 1990年第4期2卷 335-350页

作者： RIYANARTO SARNO VIReNDRA C. bHAVSAR eSAM M.A. HUSSeIN Faculty of Computer Science Canada Department of Mechanical Engineering University of New Brunswick Fredericton N.B. Canada E3B 5A3 Canada

The paper reviews existing methods for generating discrete random variab.es and their suitability for vector processing. A new method for generating discrete random variab.es for use in vectorized Monte Carlo simulations is presented. The method uses the concept of importance sampling and generates random variab.es by employing uniform distribution to speed up the computation. The sampled random variab.es are sub.equently adjusted so that unbiased estimates are obtained. The method preserves both the mean and variance of the original distribution. It is demonstrated that the method requires simpler coding and shorter execution time for both scalar and vector processing, when compared with other existing methods. The vectorization speedup of the method is demonstrated on an IbM 3090–180 machine with a vector facility.

关键词： Discrete random variab.es importance sampling Monte Carlo simulation parallel processing supercomputing vector processing

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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 reliab.e, and easily operab.e combat system. The implementation of these proposed computer systems concepts in a coherent architecture would support the future battle force capab.e combat system and allow the expansion necessary to accommodate evolutionary changes in both the threat environment and the technology then availab.e 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 possib.e 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 availab.e 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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COMPARATIVe STRUCTURAL LIFe ASSeSSMeNT OF PATROL bOAT bOTTOM PLATING

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NAVAL eNGINeeRS JOURNAL 1990年第3期102卷 253-262页

作者： AYYUb, bM WHITe, GJ beLLWRIGHT, TF PURCeLL, eS Bilal M. Ayyub:is currently an associate professor of civil engineering at the University of Maryland. He received his B.S. degree in civil engineering from the University of Kuwait in 1980. He completed both his M.S. (1981) and Ph.D. (1983) in civil engineering at the Georgia Institute of Technology. Dr. Ayyub has an extensive background in risk-based analysis. He is engaged in research work involving structural reliability marine structures and mathematical modeling using the theories of probability statistics and fuzzy sets. His research work has been sponsored by the National Transportation Safety Board National Science Foundation U.S. Coast Guard Department of Defense State of Maryland and University of Maryland. He is the author of more than 100 publications in national and international journals conference proceedings and reports. Dr. Ayyub was a recipient of the ASNE “Jimmie” Hamilton Award for 1985 the ASCE “Outstanding Research Oriented Paper” in theJournal of Water Resources Planning and Managementfor 1987 and Edmund Friedman Young Engineer Award for Professional Achievement from ASCE for 1989. Gregory J. White:is an associate professor of naval architecture at the U.S. Naval Academy. He received his B.S. degreein engineering mechanics from Vanderbilt University in 1975 an M.E. degree in naval architecture from the University of California Berkeley in 1981 and a Ph.D. in civil engineering (structures) from the University of Maryland in 1986. Dr. White served on active duty with the U.S. Navy from 1975 to 1979 as a junior officer in the engineering and operations departments of Pacific Fleet destroyers. Prior to coming to the Naval Academy he worked at Mare Island Naval Shipyard in the scientific code and in the R&D division of Exxon International company's Tanker Department. Dr. White is the author of more than two dozen technical articles and reports and is one of the U.S. representatives to the International Ship and Offshore Structures Congress (ISSC). His research interests lie in t

The estimation of an absolute life expectancy of a structure is a complex process and the results are expected to have relatively large levels of uncertainty. In this study, a comparative analysis is undertaken between two different patrol boats. This is an approach which results in a higher confidence level because certain factors common to both boats can be eliminated by assuming them to be at constant normal levels. The study is limited to the critical forward bottom plating and takes into account the differences in material, plate dimensions, operational profile, structure and loading of the two vessels. Two failure modes, plastic plate deformation and fatigue, are considered, and a novel approach to plate wastage is included. Many factors affect the structural life of a vessel. They include structural type, operational profile, structural details, loads, inspection and maintenance, design methods, safety factors, corrosion, and environmental factors. There are three types of uncertainty associated with these factors; namely, physical randomness, statistical uncertainties, and model uncertainties. The method described is designed to address these uncertainties. The ob.ective of the paper is to present the reliability-based structural life assessment method, and then to use it to evaluate and compare the structural performance of the forward bottom plating of the two patrol boats. The results of the evaluation are presented in the form of graphs and tab.es in order to facilitate the comparative evaluation. The method is performed within a computer-based format which allows parametric sensitivity analysis of several variab.es including the size of the plating panel, thickness, operational profile and loading. The sensitivity of the structural life expectancy of the forward bottom plating to variations in these parameters is evaluated.

关键词： Naval Vessels

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