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Supervisory Control of Mode-Switch Processes: Application to a Flexible BEAM

IFAC Proceedings Volumes 1992年第10期25卷 195-200页

作者： R.A. Hilhorst J. van Amerongen P. Löhnberg H.J.A.F. Tulleken Control Systems and Computer Engineering Group Department of Electrical Engineering University of Twente and Mechatronics Research Centre Twente P.O. Box 217 7500 AE Enschede The Netherlands

Many processes operate only around a limited number of operation points. In order to have adequate control around each operation point, an adaptive controller could be used. Then, if the operation point changes often, a large number of parameters would have to be adapted over and over again. This prohibits application of conventional adaptive control, which is more suited for processes with slowly changing parameters. Furthermore, continuous adaptation is not always needed or desired. An extension of adaptive control is presented, in which for each operation point the process behaviour can be stored in a memory, retrieved from it and evaluated. These functions are coordinated by a "supervisor". This concept is referred to as supervisory control. It leads to an adaptive control structure which, after a learning phase, quickly adjusts the controller parameters based on retrieval of old information, without the need to fully relcam each time. This approach has been tested on an experimental set-up of a flexible beam, but it is directly applicable to processes in e.g. the (petro)chemical industry as well.

关键词： Adaptive control Automatic tuning Learning systems Mode-switch processes Time-varying systems Supervisory control

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Fast starting, pulse primed DROs without phase noise degradation

Fast starting, pulse primed DROs without phase noise degrada...

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Microwave, MTT-S International Symposium

作者： G. Oborn E.-B. El-Sharawy Commercial Flight Systems Group Honeywell Inc. Phoenix AZ USA Department of Electrical and Computer Engineering Arizona State University Tempe AZ USA

A pulsed priming technique has been applied to series feedback DROs (dielectric resonator oscillators). Using the method, a DRO electrically tuned over 0.4% started in 60 ns without observable starting time jitter, settled to with +or-10 ppm in 150 ns, and delivered an output power of 14 dBm with a phase noise level of -92 dBc/Hz. A fixed tuned DRO also showed over 700-ns improvement in starting time when pulse primed with a phase noise level of -95 dBc/Hz. Since resonator Q reduction is not required, the inherent oscillator phase noise is not degraded. The present technique of introducing the priming signal allows for electrical tuning of the oscillator.< >

关键词： Phase noise Degradation Pulse amplifiers Jitter Feedback Acoustic reflection Coupling circuits Tuning Microwave oscillators Assembly

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Theoretical Problems in Man-Machine systems and their Experimental Validation

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IFAC Proceedings Volumes 1992年第9期25卷 19-29页

作者： G. Johannsen A.H. Levis H.G. Stassen Laboratory for Man-Machine Systems (IMAT-MMS) University of Kassel (GhK) D-3500 Kassel Germany Department of Electrical and Computer Engineering George Mason University Fairfax VA 22030 USA Man-Machine Systems Group Delft University of Technology 2628 CD Delft The Netherlands

This survey paper focusses on the main theoretical issues in today’s man-machine systems research and applications. The following problem areas are discussed: (1) modelling human performance and mental workload, with identifying the state of the art as well as major methodological difficulties; (2) task allocation and decision support, with a human-centred perspective on cooperative problem solving, integrated automation, and distributed decision making in teams; (3) man-machine interfaces, with outlining some presentation and dialogue issues; (4) design problems, with stressing the need of early active participation of man-machine-systems specialists and the usefulness of guidelines; and, finally, (5) evaluation and experimental validation, with covering laboratory and field evaluations, with covering laboratory and field evaluations, experimental design and validation, as well as model-driven experimentation. The importance of man-machine-systems contributions to the design of better technical systems and their user acceptability is emphasised.

关键词： Man-machine systems human performance modelling mental workload task allocation decision support integrated automation distributed decision making Man-machine interfaces human-centred design experimental validation

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Supervisory control of mode-switch processes: Application to a flexible beam

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Annual Review in Automatic Programming 1992年 17卷 195-200页

作者： R.A. Hilhorst J. van Amerongen P. Löhnberg H.J.A.F. Tulleken Control Systems and Computer Engineering Group Department of Electrical Engineering University of Twente P.O. Box 217 7500 AE Enschede The Netherlands Mechatronics Research Centre Twente P.O. Box 217 7500 AE Enschede The Netherlands Department of Mathematics and Systems Engineering Operational Analysis and Optimization Group Koninklijkel Shell-Laboratorium (Shell Research B.V.) P.O. Box 3003 1003 AA Amsterdam The Netherlands

Many processes operate only around a limited number of operation points. In order to have adequate control around each operation point, an adaptive controller could be used. Then, if the operation point changes often, a large number of parameters would have to be adapted over and over again. This prohibits application of conventional adaptive control, which is more suited for processes with slowly changing parameters. Furthermore, continuous adaptation is not always needed or desired. An extension of adaptive control is presented, in which for each operation point the process behaviour can be stored in a memory, retrieved from it and evaluated. These functions are coordinated by a “supervisor”. This concept is referred to as supervisory control. It leads to an adaptive control structure which, after a learning phase, quickly adjusts the controller parameters based on retrieval of old information, without the need to fully releam each time. This approach has been tested on an experimental set-up of a flexible beam, but it is directly applicable to processes in e.g. the (petro)chemical industry as well.

关键词： Adaptive control Automatic tuning Learning systems Mode-switch processes Timevarying systems Supervisory control

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Grand challenge problems in visualization software 3

Grand challenge problems in visualization software

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3rd Conference on Visualization, VIS 1992

作者： Treinish, Lloyd A. Butler, David M. Senay, Hikmet Grinstein, Georges G. Bryson, Steve T. Scientific Visualization Systems Group IBM T.J. Watson Research Center Yorktown HeightsNY United States Center for Computational Engineering Sandia National Laboratories LivermoreCA United States Department of Electrical Engineering and Computer Science George Washington University WashingtonDC20052 United States Institute for Visualization and Perception Research University of Massachusetts at Lowell LowellMA01854 United States NASA Ames Research Center Moffett FieldCA94035 United States

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Grand challenge problems in visualization software 92

Grand challenge problems in visualization software

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IEEE Conference on Visualization

作者： L.A. Treinish D.M. Butler H. Senay G.G. Grinstein S.T. Bryson Scientific Visualization Systems Group IBM Thomas J. Watson Research Center Yorktown Heights NY USA Center for Computational Engineering Sandia National Laboratories Livermore CA USA Department of Electrical Engineering and Computer Science George Washington University DC USA Institute for Visualization & Perception Research University of Massachusetts Lowell Lowell MA USA NASA Ames Research Center CA USA

ISBN: (纸本)9780818628962

Discusses issues relating to the complexity of scientific visualization software system implementation. It is argued that the complexity of current implementations of such systems may limit the utility for users because the interfaces typically require significant knowledge of the data being studied and the applicable visualization algorithms, as well as its infrastructure of graphics, imaging and data handling technology. The issues, unknowns, and possible solutions associated with building effective scientific visualization software are discussed.< >

关键词： Data visualization Data handling Data analysis Software tools Laboratories Software systems Data structures Graphics Application software Software architecture

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Simulation of electromagnetic radiation and scattering using a finite difference-time domain technique

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computer Applications in engineering Education 1992年第1期1卷 45-45页

作者： Li, K. Tassoudji, M.A. Shin, R.T. Kong, J.A. Department of Electrical Engineering and Computer Science and Research Laboratory of Electronics Massachusetts Institute of Technology Cambridge Massachusetts 02139 Kevin Li:received his BS and SM degrees (1990) in Electrical Engineering and EE (Electrical Engineer's) degree (1991) from the Massachusetts Institute of Technology where he is currently pursuing his PhD in Electrical Engineering. Since 1990 he has been the recipient of a United States Air Force Laboratory Graduate Fellowship. His main research interests include electromagnetic scattering radar cross section prediction and numerical techniques. Mr. Li is a member of Tau Beta Pi and a student member of IEEE. M. Ali Tassoudji:received his BS (1987) and MS (1989) degrees in Electrical Engineering from the University of Michigan Ann Arbor. Since 1989 he has been a research assistant at the Massachusetts Institute of Technology where he is currently working towards his PhD in Electrical Engineering. His research interests include electromagnetic scattering and propagation modeling of microwave circuits and numerical techniques. Mr. Tassoudji is a member of IEEE and Eta Kappa Nu. Robert T. Shin:received his SB (1977) SM (1980) and PhD (1984) in Electrical Engineering from the Massachusetts Institute of Technology. Since 1984 he has been a member of the Air Defense Techniques Group at MIT Lincoln Laboratory as a Research Staff member and as a Senior Staff member from 1989. His research interests are in the areas of electromagnetic wave scattering and propagation theoretical model development and data interpretation for microwave remote sensing. He is the coauthor ofTheory of Microwave Remote Sensing(Wiley 1985). Dr. Shin is a member of The Electromagnetics Academy IEEE American Geophysical Union Tau Beta Pi Eta Kappa Nu and Commission F of the International Union of Radio Science. Since 1987 he has served on the Editorial Board of theJournal of Electromagnetic Waves and Applications(JEWA). Jin Au Kong:is Professor of Electrical Enginee

The finite difference-time domain (FD-TD) technique is applied to the solution of Maxwell's equations. A computer program, which can be used to simulate and study numerous electromagnetic phenomena, is developed and implemented on an IBM 386 compatible personal computer. The FD-TD technique is a useful tool for students in electromagnetics. The technique is flexible and can be applied to many basic EM scattering and radiation problems. Because field solutions are found as a function of time, visualization of the propagation of the EM fields is possible. The FD-TD technique is implemented for a two-dimensional rectangular grid in conjunction with a second-order absorbing boundary condition. Both E- and H-field polarizations are analyzed. Finite objects consisting of dielectric, magnetic and conducting materials, and perfectly conducting infinite ground planes are modeled. Plane wave and line current sources are implemented. In addition to the capability of animating the propagation of the EM fields, radiation and scattering patterns can be generated.

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DEGREES OF CYCLOSTATIONARITY AND THEIR APPLICATION TO SIGNAL-DETECTION AND ESTIMATION

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SIGNAL PROCESSING 1991年第3期22卷 287-297页

作者： ZIVANOVIC, GD GARDNER, WA Computer Systems Design Laboratory “Boris Kidrič” Institute Vinča P.O. Box 522 11001 Belgrade Yugoslavia Signal Processing Group Department of Electrical Engineering & Computer Science University of California Davis CA 95616 USA

The problem of defining an appropriate measure of the degree of nonstationarity for stochastic processes that exhibit cyclostationarity is addressed. After discussing several candidate measures of degree of nonstationarity, one particularly promising measure is adopted. By decomposing this measure, several component measures are arrived at. Bounds on these measures are derived and their utility in applications involving signal detection and estimation is established. Examples are presented to illustrate the calculation of degrees of nonstationarity for several types of cyclostationary signals.

关键词： CYCLOSTATIONARY PROCESS DEGREE OF CYCLOSTATIONARITY INSTANTANEOUS SPECTRUM SPECTRAL CORRELATION

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Model Quality and Optimal Identification for Control

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IFAC Proceedings Volumes 1991年第3期24卷 817-822页

作者： P. Löhnberg B. Franke Control Laboratory Control Systems and Computer Engineering Group Department of Electrical Engineering University of Twente Enschede The Netherlands

Optimal parameter estimation and experiment design requires a weighting between the cost of parameter errors and that of identification itself. Having identified this need, the general principle to obtain both costs for using the model in control design is described. Fast experiment design is achieved by using analytic expressions to calculate the optimal experiment parameters. This is illustrated by a simple example. It is shown that the use of the resulting model criterion in optimal identification is equivalent to cautious stochastic control. A more realistic example is illustrated by simulation.

关键词： Bayes methods least squares approximation optimal control optimization parameter estimation random processes

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Developing Conductive Elastomers for Applications in Robotic Tactile Sensing

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Advanced Robotics 1991年第2期6卷 255-271页

作者： Uldry, Jean-Pierre Andrew Russell, R. Intelligent Robotics Group Department of Electrical and Computer Systems Engineering Monash University Melbourne Australia

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