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Development and integration of an equation-solving program for engineering thermodynamics courses

computer Applications in engineering Education 1993年第3期1卷 265-265页

作者： Klein, S.A. Mechanical Engineering Department University of Wisconsin-Madison 53706 Dr. S. A. Klein:is a professor of Mechanical Engineering at University of Wisconsin-Madison. His engineering degrees (BS University of Illinois-Chicago MS PhD University of Wisconsin-Madison) were obtained in Chemical Engineering. Professor Klein is a member of the Solar Energy Laboratory at Wisconsin. He is the developer of the F-Chart method for sizing solar heating systems and the TRNSYS simulation program which is widely used in simulations of solar processes. Currently Professor Klein is involved in research on solar energy system performance absorption power cycles finite-time thermodynamics applications adsorption processes for air conditioning and air quality control and alternative refrigerants and systems for refrigeration and air conditioning applications. Professor Klein is also involved in the development of engineering computer tools for both instruction and research. In addition to the EES program described in this paper he is the primary author of the thermodynamics instructional program CP/Thermo and the finite element program FEHT.

Thermodynamics problems can be separated into conceptual and mathematical parts. The conceptual part consists of the problem formulation and analysis. The mathematical part seeks to obtain an answer to a problem by solving the equations identified in the analysis. The mathematical part can be complex and time-consuming and often directs the students' focus away from the concepts. An equation solving program called engineering Equation Solver (EES) was developed to reduce the time and effort required by students to solve the mathematical part of thermodynamics problems. EES differs from existing equation solving programs in that it is designed for use by students and it includes an extensive library of built-in functions for thermodynamic and transport properties of fluids. Thermodynamic and transport property data needed for solving engineering problems (eg, steam tables, refrigerant properties, psychrometric and combustion gas data) are built into the program. By eliminating table lookups and algebra, EES allows students to concentrate on engineering fundamentals, as well as to do more complex design problems.

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Steady‐state modelling of a uniform pulse‐width modulated single‐phase AC‐to‐DC converter‐fed DC motor drive

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European Transactions on Electrical Power 1993年第5期3卷 379-386页

作者： Hamed, S.A. Dr. Sadeq A. Hamed (1957) received his B.Sc. degree in Electrical Power Engineering from Damascus University Syria in 1980. From 1980 to 1982 he has been with the Department of Electrical Engineering at the University of Jordan Ammad/Jordan. He obtained the M.Sc. degree in Power Electronics and Systems and the PhD degree in Power Electronics from the University of Manchester Institute of Science and Technology (UMIST) Manchester/GB in 1983 and 1986 respectively. In 1986 he joined the Department of Electrical Engineering. Jordan University as an Assistant Professor. In 1991 became an Associate Professor at the same department. His research activities include modelling and simulation of AC/DC drive systems pulse-width modulation control of motor implementation of computer-controlled drive systems energy saving in the electrical drive industry. (Jordan University Department of Electrical Engineering Amman/Jordan T + 96 26/843555 - 28 13 Fax + 9626/8485 58)

With the increasing availability of power transistor switches, PWM controlled rectifiers can efficiently and economically be employed in low and medium power applications of DC drive systems. In this paper, steady‐state modelling and solution of a uniform pulse‐width modulated single‐phase AC‐to‐DC converter‐fed DC motor drive is accomplished. The developed model is presented in a generalized form that is applicable irrespective of the number of pulses per supply half‐cycle. Measured and predicted parameters are shown to be very close and the model is proved to be efficient and accurate. Both continuous and discontinuous modes of operation are covered, and critical operating conditions at which the system moves from one mode to the other are thoroughly investigated. The effects of the armature inductance‐to‐resistance ratio and the chopping frequency on these critical conditions, load and line harmonics, and on the ripple contents of the armature current are also thoroughly investigated. Copyright © 1993 John Wiley & Sons, Ltd.

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An approach to the direct analysis of transient stability

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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 been intensely investigated over the last decade as a reliable 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 (T_CCT) 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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computer‐aided calculation of the steady‐state thermal performance characteristics of low‐voltage circuit breakers

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European Transactions on Electrical Power 1993年第5期3卷 347-352页

作者： Völker, F. Dr.-Ing. Frank Völker (1958) VDI studied mechanical engineering special subjects “powerengineering automatic control engineering and mechanical science” at the University-GH-Duisburg/Germany where he got his Dipl.-Ing. degree in 1984. From 1984 to 1990 he has been a scientific assistant at the department “Konstruktionslehre und Fördertechnik” special subject “computer simulation of the performance characteristics of driving systems” at the same University where he received his Dr.-Ing. degree in 1990. In 1990 he joined Klöckner-Moeller GmbH Bonn/Germany as research engineer at the department “Forschung”. Since 1992 he is manager of Energy Management Systems at this company. (Klöckner-Moeller GmbH Head Office Energy Management Systems Hein-Moeller-Str. 7-11 D-53115 Bonn T +49228/602 - 11 62 Fax +49228/602- 11 94)

A discrete thermal network is given as an equivalent circuit of the steady‐state thermal performance characteristics of circuit breakers. The immediate environment of the enclosure and the feeders of the unenclosed switching device are the boundaries of the equivalent circuit, which specifically models the central phase of a three‐phase circuit breaker. computer simulations make it possible to analyse the thermal system performance in rated service. Selected examples prove the high quality of the model and the efficiency of the described method of calculation. Copyright © 1993 John Wiley & Sons, Ltd.

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ACCURACY REQUIREMENTS FOR MEASUREMENT systems WITH UNIFORM AND NORMAL ERRORS

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NAVAL ENGINEERS JOURNAL 1993年第1期105卷 66-69页

作者： SNOW, JM STUCKMAN, BE USHER, JS Jeffrey M. Snow:received his B.S. degree in mechanical engineering from the University of Washington in 1977. He has worked at Boeing Commercial Aircraft Company and Puget Sound Naval Shipyard. Since 1985 he has been at Naval Surface Warfare Center Crane Division (NSWCC). From 1987 to 1990 he was in charge of quality assurance configuration management and reliability for Aegis (SPY-1 and Mk-99) microwave tubes. He currently is in the Radar System Branch at NSWCC. He is a member of ASQC and ASME. His areas of interest include the use of statistics in process improvement efforts and objectively rating and rewarding suppliers for better quality. Bruce E. Stuckman:holds a Ph.D. degree in systems engineering from Oakland University where he also obtained M.S. and B.S. degrees in electrical and computer engineering. In 1992 Dr. Stuckman obtained his J.D. from the University of Louisville where he graduated cum laude. He is currently an associate in the patent and computer law department of Brooks & Kushman a law firm specializing in intellectual property and technology related causes. Prior to this he was an associate professor of both electrical engineering at the University of Louisville and a member of the Research Advisory Board of the South Central Bell Telecommunications Research Center. Dr. Stuckman is the author of over 75 published works in a variety of research areas including global optimization algorithms control systems communication and telecommunication systems and instrumentation electronics. He has served as a technical consultant to such organizations as Control Data Corporation General Electric General Motors Research Laboratories Gulf & Western AT&T Bell Laboratories ARCO Research and Technical Services and the U.S. Government and has been a frequent lecturer at national and international symposia. He is a senior member of IEEE and a member of ASNE Eta Kappa Nu Tau Beta Pi Sigma Xi and Phi Kappa Phi. John S. Usher Ph.D. P.E.:is an assistant professor of industrial engineering

Accuracy requirements are usually determined as a percentage of the specification range of the measured part or process. Setting accuracy requirements in this manner results in a wide and unpredictable range of false rejection and acceptance probabilities. This causes extra costs due to either: 1) over specification of measurement systems accuracy requirements;2) time, effort, retesting, and resolution of false rejections;or 3) system degradation caused by false acceptance of out-of-specification parts. Achieving a consistent and known risk of false acceptance is only possible by considering the measured process C(pk), the process's mean in relation to the center of the specification range, and the measurement system error distribution. This paper presents a method for calculating the probabilities of false rejection and false acceptance for a normal process which is measured with, alternately, uniform and normally distributed error. It is shown that under most conditions uniform error causes 20% to 30% higher false rejection and acceptance probabilities. Thus, knowledge of measurement error distribution could provide lower total production cost.

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Measurements of power and current components in unbalanced and distorted three‐phase systems

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European Transactions on Electrical Power 1993年第1期3卷 75-83页

作者： Andria, G. Salvatore, L. Savino, M. Trotta, A. Dr. Gregorio Andria (1956) AEI received the M. S. degree in Electrical Engineering from the State University of Bari/Italy in 1981 and the Ph. D. degree in Electrical Engineering in 1987 from the same University. From 1981 to 1983 he was working in the Electrotechnics and Electronics Department of the University of Bari as a member of the research team on electrical measurements. From 1984 to 1986 he was a Doctoral Fellow and currently he is a researcher in the same department. His research interests are in the fields of electrical and electronic measurements on components and systems including digital measurements for the analysis of electrical quantities in non-sinusoidal systems and the design of integrated optical sensors for measurement and control of non-electrical physical quantities. (Department of Electrotechnics and Electronics Faculty of Engineering polytechnic of Bovia E. Orabona 4 1-70125 Bari. Italy T +3980/242266 Fax + 3980/242410) Prof. Luigi Salvatore (1945) AEI received the degree in electrical engineering from the University of Bari/Italy in 1970. Since 1976 he has worked in the Electrotechnical and Electronic Department of the same University as a member of the research team on electrical machines. From 1983 to 1987 he was a researcher of electrical machines in the same department. Since 1987 he has been an Associate Professor of electrical machines at the University of Bari. At the present time his research interests include the control monitoring and diagnostics of AC drives and the areas of signal processing anddigital measurements on power electronics systems. (Department of Electrotechnics and Electronics Faculty of Engineering Polytechnic of Bari via E. Orabona 4 I-70125 Bari Italy T + 3980/242258 Fax + 3980/242410) Prof. Mario Savino (1947) AEI received the degree in Electrical Engineering from the University of Barif Italy in 1971. Since then he has been working in the Electrotechnical Institute of Bari until 1973 as researcher from 1973 to 1982 as Assistant Profe

The paper deals with the instantaneous power theory in three‐phase circuits by using the instantaneous time phasors of voltage and current. Particularly it is shown that the instantaneous components of the current time‐phasor in a rotating reference frame p‐q, oriented in such a way that the instantaneous voltage time‐phasor points to the p‐axis direction, represent the active and reactive currents. These components give rise to instantaneous real and imaginary powers, respectively. The spectral analysis of the above‐mentioned time‐phasors gives the harmonic symmetrical components of positive and negative sequence of voltage and current three‐phase systems. The line‐by‐line product of the voltage sequence spectrum by the complex conjugate of the current sequence spectrum gives the DC components of the instantaneous real and imaginary powers. The paper shows also that the instantaneous active and reactive currents are different from those defined on grounds of the Fryze's theory, which can be determined from the voltage and current sequence spectra. Copyright © 1993 John Wiley & Sons, Ltd.

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SHIPBOARD DAMAGED STABILITY ASSESSMENT - THE FLOODING CASUALTY control SOFTWARE

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NAVAL ENGINEERS JOURNAL 1993年第3期105卷 152-166页

作者： ZAHN, PB ROSBOROUGH, J CARLSTROM, R Peter B. Zahn:is a section chief in the Naval Architecture Department at Advanced Marine Enterprises. He is responsible for software development and special trials support. He has led the Flooding Casualty Control Software (FCCS) development effort since joining AME in 1989. He is also responsible for the material handling strikedown and stowage (MHS&S) software development program as well as special trials support for the ACVLAP and T-AGOS 19 programs. Prior to joining AME Mr. Zahn spent nine years with various companies of the ARCTEC Group. His experience includes field trials in venues from the Caribbean to the Bering Sea as well as model tests and engineering design and development efforts. Mr. Zahn received his B.S. in naval architecture and marine engineering from Webb Institute in 1980 and has published various papers on pollution prevention offshore systems and icebreaker design and performance. He is a member of ASNE and SNAME. John Rosborough:has been a naval architect for the Naval Sea Systems Command (NavSea) for the past 15 years. He is currently assigned to the Hydrodynamics Division with responsibility for aircraft carrier stability evaluations and as a task leader for computer-aided ship design development. In the Stability Division he was previously responsible for stability analyses on various amphibious ships SWATHs and foreign ships. He manages the upgrade and augmentation of SHCP at NavSea and is the Navy's technical point of contact for evaluating shipboard stability software and transitioning technology to the fleet. Mr. Rosborough received his B.S. in naval architecture and marine engineering from the University of Michigan in 1977. He is a member of USNI and the Association of Scientists and Engineers at NavSea. Richard Carlstrom:is a naval architect with Advanced Marine Enterprises. He has been responsible for software development in support of a variety of major programs including FCCS and SHCP and is a specialist in stability evaluations for complex ships such as CVs CVNs

The Flooding Casualty control Software (FCCS) was developed under the auspices of the Naval Sea systems Command (NavSea) and is currently being deployed on a variety of ships in the neets of both the U.S. Navy and the U.S. Coast Guard. The primary objective of FCCS is to enable damage control personnel to identify critical stability conditions, especially when related to the loss of reserve buoyancy due to battle damage and the destabilizing effects of large quantities of firefighting water, in a timely manner. FCCS was initially deploved in 1990. It utilizes the standard algorithms of the Ship Hull Characteristics Program (SHCP). The user interface was designed to allow quick familiarity for shipboard users, primarily the damage control assistant (DCA) and his staff. Intact stability evaluations include the effects of topside icing, high winds, personnel crowding, heavy lifts over the side, high speed turns, and towing. FCCS also supports ballasting analysis for amphibious ships as well as providing bottom reaction and beached stability data for grounding incidents. Bv providing a tool for the ''fuel king'' and DCA to generate the required daily updates on the current ship load and liquids status, FCCS is assured of an accurate baseline in the event of damage. The design allows the evaluation of the ultimate ship stability status for a damage event using simple compartmentation and flooding status inputs. Evaluation of the adequacy of resulting stabilitv, as well as identification of such critical stability parameters as off center loading, margin line immersion, and negative GM, are accomplished by the program. Guidance is provided for the user to initiate appropriate flooding related damage control activities. Initially fitted on USS Oliver Hazard Perry Class frigates, FCCS databases have been for the USCG Hamilton class high endurance cutters, USS Arleigh Burke class Aegis destroyers, and a variety of other U.S. Navy and U.S. Coast Guard ship classes. The progra

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ON PETRI NET MODELS OF INFINITE STATE SUPERVISORS

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IEEE TRANSACTIONS ON AUTOMATIC control 1992年第2期37卷 274-277页

作者： SREENIVAS, RS KROGH, BH Laboratory for Automated Systems and Information Processing Department of Electrical Engineering and Computer Engineering Carnegie Mellon University Pittsburgh PA USA

We consider a class of supervisory control problems that require infinite state supervisors Petri nets with inhibitor arcs (PN's) to model the supervisors. We compare this PN-based approach to supervisory control to automata-based approaches. The primary advantage of a PN-based supervisory controller is that a PN-based controller provides a finite representation of an infinite state supervisor. For verification, implementation, and testing reasons, a finite PN-based representation of an infinite state supervisor is preferred over an automata-based supervisor. We show that this modeling advantage is accompanied by a decision disadvantage, in that in general the controllability of a language that can be generated by the closed-loop system is undecidable.

关键词： Supervisory control Automatic control Petri nets Inhibitors control systems Automata Discrete event systems control system synthesis Automatic testing

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DISTRIBUTED DETECTION WITH CONSULTING SENSORS AND COMMUNICATION COST

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IEEE TRANSACTIONS ON AUTOMATIC control 1992年第9期37卷 1398-1405页

作者： THOMOPOULOS, SCA OKELLO, NN Department of Electrical and Computer Engineering Decision and Control Systems Laboratory Pennslyvania State University University Park PA USA

The problem of distributed detection with consulting sensors in the presence of communication cost associated with any exchange of information (consultation) between sensors is considered. We consider a system of two sensors, S1 and S2, in which S1 is the primary sensor responsible for the final decision u0, while S2 is a consulting sensor capable of relaying its decision u2 to S1 when requested by S1. In the scenario that is considered, the final decision u0 is based either on the raw data available to S1 only, or it may, under certain request conditions, also take into account the decision u2 of sensor S2. Random and nonrandom request schemes are analyzed and numerical results are presented and compared for Gaussian and slow-fading Rayleigh channels. For each decision making scheme, an associated optimization problem is formulated whose solution is shown to satisfy certain a priori set design criteria that we consider essential for sensor fusion.

关键词： Costs Sensor fusion control systems Sensor systems Frequency Communication system control Servomechanisms Steady-state Polynomials Error correction

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Experimental study of the identification methods for an industrial robot manipulator

Experimental study of the identification methods for an indu...

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1992 IEEE/RSJ International Conference on Intelligent Robots and systems, IROS 1992

作者： Yoshida, K. Ikeda, N. Mayeda, H. Department of Control Engineering Osaka University Japan Department of Computer and Systems Engineering Ritsumeikan University Japan

ISBN: (纸本)0780307372

Two identification methods;"stepby-step method" and "simultaneous method" which takes advantage of the instrumental variable method are experimentary examined to estimate the parameters of the dynamic model of the PUMA 560. To evaluate the accuracy of the estimates we compare simulated trajectories with measured trajectory. It can be concluded that the two methods are neary same precise way to estimate the model parameters. © 1992 Institute of Electrical and Electronics Engineers Inc. All rights reserved.

关键词： Robot applications

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