检索结果-内蒙古大学图书馆

PERFORMANCE OF A PRIORITIZED ON-BOARD BASEBAND SWITCH FOR A MULTISERVICE MULTIBEAM SATELLITE

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 283-297页

作者： BOHM, S ELHAKEEM, AK HACHICHA, M Department of Electrical and Computer Engineering Concordia University 1455 De Maisonneuve Blvd. West Montreal H3A 1M8 Canada Was born in Montreal Canada on 14 September 1966. He received the B. Eng. degree in electrical engineering from Concordia University Montreal Canada in 1989. He is at present completing the M.A.Sc. degree in electrical engineering at Concordia University. (S'75–S'79–M'79–SM'86) received the Ph.D. degree from Southern Methodist University Dallas TX in 1979. He spent the next two years working as a Visiting Professor in Egypt after which he moved to Ottawa Canada in 1982. He assumed teaching and research positions in Carleton and Manitoba Univerities and later moved to Concordia University Montreal Canada in 1983 where he is now a Professor in the Electrical and Computer Engineering Department. He has published numerous papers in IEEE and international journals in the areas of spread spectrum and networking. He is a well-known expert in these areas and serves as a consultant to many companies. His current research interests include wide-band metropolitan networks switching architectures and performance of on-board multibeam satellites acquisitionless CDMA networks code distribution and orthogonalization of CDMA signals responsive congestion control for ATM-based networks ARQ techniques and investigation of the novel SUGAR CDMA systems in fading channels. Dr. Elhakeem is a Senior Member of the Canadian Electrical Engineering Society and Armed Forces Association. He has chaired numerous technical sessions in IEEE Conferences was the Technical Program Chairman for IEEE Montech 1986 Montreal Canada. Dr. Elhakeem is the key guest editor of theIEEE Journal of Selected Areas in Communicationsfor the May June issues 1993 covering CDMA networks. Advanced Technology & Networks VISTAR Telecommunications Inc. Ottawa Ontario K1G 3J4 Canada An Associate Director of Advanced Technology & Networks Group VISTAR Telecommunications Inc. Ottawa Canada. He is also an Adjunct Pr

In this paper, we study the performance of a prioritized on-board baseband switch in conjunction with a multibeam satellite handling integrated services. The services considered for the analysis include voice, video, file transfer and interactive data. The prioritized switch uses both input and output buffering, switch speed-up as well as a two-phase head-of-line resolution algorithm, in order to reduce the buffer loss while maintaining acceptable user delays. The minimum required buffer capacity and switch speed-up for each service in a prioritized environment are found under uniform traffic conditions. It is shown that under uniform traffic conditions, only minimal buffering and switch speed-up are needed even for the lowest priority users. The performance dependence on the switch size is also substantially reduced with head of line resolution and buffering even in a prioritized environment.

关键词： SWITCH ON-BOARD BASEBAND MULTIBEAM PRIORITIZED HEAD-OF-LINE UNIFORM LOAD SPEED-UP

来源：评论

学校读者我要写书评

暂无评论

Providing high-level control and expert assistance in the user interface presentation design 93

Providing high-level control and expert assistance in the us...

引用

Proceedings of the INTERCHI '93 Conference on Human Factors in Computing Systems

作者： Kim, Won Chul Foley, James D. Department of Electrical Engineering and Computer Science The George Washington University Washington DC Graphics Visualization and Usability Center College of Computing Georgia Institute of Technology Atlanta GA

ISBN: (纸本)9051991339

Current user interface builders provide only low-level assistance, because they have knowledge of neither the application, nor the principles by which interface elements are combined effectively. We have developed a framework that unites the knowledge components essential for effective user interface presentation design. The framework consists of an application model (both a data model and a control model), a design process model that supports top-down iterative development, and graphic design knowledge that is used both to place dialog box elements such that their application dependent logical relationships are visually reinforced and to control design symmetry and balance. To demonstrate the framework's viability, we have constructed a tool based on encapsulated design knowledge that establishes high-level style preferences and provides expert assistance for the dialog box presentation design and menu structuring.

关键词： UI design process

来源：评论

学校读者我要写书评

暂无评论

SIGNALS. Interactive software for one-dimensional signal processing

引用

computer Applications in Engineering Education 1993年第6期1卷 489-489页

作者： Easton, R.L. Jr. Chester F. Carlson Center for Imaging Science Rochester Institute of Technology 54 Lomb Memorial Drive Rochester NY 14623-5604 Roger L. Easton Jr.:is an Assistant Professor in the Chester F. Carlson Center for Imaging Science at the Rochester Institute of Technology. He received the B.S. degree in Astronomy from Haverford College the M.S. in Physics from the University of Maryland and the M.S. and Ph.D. degrees in Optical Sciences from the University of Arizona. He is a member of SPIE OSA and IEEE. His interests include optical signal processing digital image processing in astronomy digital halftoning and computer-generated holography.

This article describes the features of a DOS program that was written for interactive demonstrations of one-dimensional (1-D) signal processing concepts in a classroom environment. It also is used to illustrate aspects of linear systems, physical optics, and complex numbers. The program is menu-driven, and experience has proven that it is easy to learn and use. Complex-valued functions are loaded from a sizeable menu of options and may be processed in a variety of ways and plotted in several formats. Data files may be input from or output to other applications, e.g. spreadsheets.

关键词：

来源：评论

学校读者我要写书评

暂无评论

STATISTICAL PROCESS-CONTROL FOR SOFTWARE IN THE MAINTENANCE PHASE

引用

NAVAL ENGINEERS JOURNAL 1993年第3期105卷 192-200页

作者： LUKE, SR JACOBS, DA REED, BM Stephen R. Luke:is a registered professional engineer in the Commonwealth of Virginia. He received his B.S. in mechanical engineering from Virginia Polytechnic Institute in 1983 and is presently pursuing a master's degree in engineering management at Old Dominion University. Mr. Luke is experienced as a test engineer at the Norfolk Naval Shipyard (1978–1989) and as a reliability/quality engineer at the Naval Undersea Warfare Center Detachment Norfolk (1989-Present). Currently he is the group leader of the RMA/QA group for the AN/SQQ-89(V) Antisubmarine Warfare System at Naval Undersea Warfare Center Detachment Norfolk. Mr. Luke is a member of ASNE IEEE (Reliability Society) and ASQC and is an ASQC certified quality engineer and reliability engineer. Derya Alasya Jacobs:is an assistant professor in the Engineering Management Department at Old Dominion University (ODU). She has a B.S. in computer science and an M.S. and Ph.D in engineering management from the University of Missouri-Rolla. Prior to joining ODU Dr. Jacobs worked as a research engineer at the Center for Technology Transfer and Economic Development at the University of Missouri-Rolla. During the same period she served as a consultant in software development for Missouri Enterprise Rolla Missouri. Dr. Jacobs' research interests are in the areas of applied artificial intelligence decision support systems operations research and computer integrated manufacturing. Billie M. Reed:is an assistant professor in the Engineering Management Department at Old Dominion University. He received a B.S. degree in mechanical engineering from Auburn University in 1971. After completing undergraduate studies Dr. Reed was commissioned as an officer in the U.S. Navy where he served in the nuclear submarine force until 1982. Following his military career Dr. Reed worked for nine years as a systems engineer and human-machine interface designer of complex interactive computer based systems for use in aircraft space and ship systems. He received his M.S. and Ph

As technology advances and our dependency on software increases, the requirement to develop the correct means to improve quality in both the deveiopment phase and the maintenance phase of software life cycle support becomes increasingly significant. The focus of this paper is on the dilemma facing software engineering in maintaining quality within the constraints of the maintenance phase. The paper further proposes that the software maintenance process can also be analvzed and improved using statistical process control (SPC) techniques. The methods discussed in this paper have been proposed for use in the Software Maintenance project at NUWC Detachment Norfolk. Upon successful testing at NUWC Detachment Norfolk, they will be forwarded to the AN/SQQ-89(V) (interagencv) Software Quality Evaluation Committee for use by other agencies which are developing and maintaining AN/SQQ-89(V) software.

关键词：

来源：评论

学校读者我要写书评

暂无评论

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

引用

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.

关键词：

来源：评论

学校读者我要写书评

暂无评论

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

引用

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.

关键词：

来源：评论

学校读者我要写书评

暂无评论

An approach to the direct analysis of transient stability

引用

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.

关键词：

来源：评论

学校读者我要写书评

暂无评论

EXTRACTING CONTOURS BY PERCEPTUAL GROUPING

引用

IMAGE AND VISION COMPUTING 1992年第2期10卷 77-88页

作者： KHAN, GN GILLIES, DF Computer Vision and Graphics Group Department of Computing Imperial College of Science Technology and Medicine 180 Queen's Gate London SW7 2BZ UK

A new contour extraction method is described in this paper. It is based on organization of the image data using perceptual grouping rules, and is therefore largely domain independent. The first step is to form an intermediate line segment representation of the contours by grouping edge points in parallel and at different resolutions. The main feature of the line segment extraction process is the identification, by perceptual criteria, of weak but significant edge points for participation in the grouping process. In the second stage the line segments are grouped into contours, again on the basis of perceptual criteria. This grouping stage is carried out hierarchically using a pyramid structure. In both cases, the use of perceptual grouping allows the filtering of noisy edges and line segments regardless of their strength.

关键词： LINE AND CONTOUR EXTRACTION HOUGH TRANSFORM PERCEPTUAL GROUPING PYRAMID PROCESSING

来源：评论

学校读者我要写书评

暂无评论

Stabilizers enhancing the frequency regulation action of HVDC links supplying weak AC systems

引用

European Transactions on Electrical Power 1993年第3期3卷 201-212页

作者： Maris, T.I. Lygdis, A.D. Vovos, N.A. Giannakopoulos, G.B. Theodoros I. Maris (1961) received the Diploma in Electrical Engineering from the University of Patras/Greece in 1984. In 1985 he joined the Power Systems Laboratory at the Electrical Engineering Department of the University of Patras as research assistant where he is currently working for his Ph.D. degree. His area of interest is HVDC transmission. (University of Patras Dep. of Electrical Engineering Power Systems Laboratory GR-26 500 Rion. Patras/Greece T +3061/997350 Fax +3061/997362) Athanassios D. Lygdis (1954) received the Diploma in Electrical Engineering from the University of Patras/Greece in 1979. From 1979 until 1982 he worked at the Nuclear Technology Laboratory of the University of Patras as research assistant. In 1983 he joined the Power Systems Laboratory at the Electrical Engineering Department of the University of Patras as scientific collaborator. He is now working for his Ph.D. degree in this Department. His main field of interest is power transmission by HVDC systems. (University of Patras Dep. of Electrical Engineering Power Systems Labora- tory GR-26 500 Rion Patras/Greece T + 3061/997350 Fax + 3061/997361) Nickolas A. Vovos (1951) received the Diploma degree from the University of Patras/Greece the M.Sc. degree from the University of Manchester/England Institute of Science and Technology. and the Ph.D. degree from the University of Patras in 1974 1975 1978 respectively all in Electrical Engineering. In 1976 he joined the Power Systems Laboratory at the Electrical Engineering Department of the University of Patras where he is now Associate Professor. His main fields of interest are the modeiling and the transient stability study of integrated AC/DC systems. He is a member of the IEEE Power Engineering Society and CIGRE and a registered professional Engineer and member of the Technical Chamber of Greece (University of Patras Dep. of Electrical Engineering Power Systems laboratory GR-26500 Rion Patras/Greece. T +3061/997369 Fax +3061/997362) Gabriel B. Giannakopoulos (1

Power System Stabilizers (PSS) superimposed to the basic control system of an HVDC link supplying a weak AC system, in order to enhance its frequency regulation action, are proposed. To decrease the AC voltage sensitivity at the inverter side, the basic control system of the HVDC link is proposed to operate with the rectifier under Minimum Ignition Angle (MIA) control and the inverter under Constant Current (CC) control. Inputs to the PSS are the frequency and the AC voltage deviations at the inverter side and their constant parameters are calculated using modal control technique. Detailed simulation results for a practical integrated AC/DC system are presented to evaluate the performance of the proposed control scheme. Copyright © 1993 John Wiley & Sons, Ltd.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Real virtual environment applications - Now 3

Real virtual environment applications - Now

引用

3rd Conference on Visualization, VIS 1992

作者： Breen, Paul T. Grinstein, Georges G. Mizell, David W. Satava, Richard M. Smith, Bradford Stephens, Michael M. Zeltzer, David Department Head Applied Technology MITRE Corporation BedfordMA United States Continental C3 MITRE Corporation BedfordMA United States Institute for Visualization and Perception Research Computer Science Department University of Massachusetts Lowell LowellMA United States Computing Systems and Environments Boeing Computer Services SeattleWA United States General Surgery Silas B. Hays Army Hospital Fort OrdCA United States University of San Francisco BerkeleyCA United States System Engineering Division Computer Sciences Corporation VicksburgMS United States Computer Graphics and Animation Group Media Laboratory Massachusetts Institute of Technology CambridgeMA United States

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：