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Applications of Digital Image Processing XII 1989

作者： Khan, Gul N. Gillies, Duncan F. Department of Computing Computer Vision and Graphics Group Imperial College of Science Technology and Medicine 180 Queen's Gate LondonSW7 2BZ United Kingdom

A highly parallel technique for linking line segments into curved contours or boundaries has been developed. This bottom-up organization of the line segments utilizes information in the line data itself and perceptual organization rules which are domain independent. The line segments can be detected on a local basis and are amenable to parallel computation. 1 A line pyramid structure is employed where the two bottom levels of the pyramid hold the line segments extracted from pre-defined image windows (e.g. 4x4 and 8∗8). The pyramid is based on a 4x4 overlapping neighbourhood and each processing element is connected to four parents and sixteen children. Starting from the lower level, each processing element performs grouping on the line data supplied by all of its children but it only keeps the grouped line segments supplied by its central 2x2 children for passing on to the parents. The main grouping criteria employed to achieve the aggregation of line segments are proximity, Marr's theta-aggregation,^ curvilinearity, continuity and similarity in line contrast. By the time the root processor of the pyramid is reached, all the groups of line segments are formed and they are then replaced by contours. The main features of the method are its parallel implementation on a pyramid architecture computer and use of domain independent perceptual grouping principles. © 1990 SPIE. All rights reserved.

关键词： computer architecture

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CAFE-the MIT computer aided fabrication environment

CAFE-the MIT computer aided fabrication environment

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IEEE/CHMT(CPMT) International Electronics Manufacturing technology Symposium

作者： M.B. McIlrath D.E. Troxel D.S. Boning M.L. Heytens P. Penfield R. Jayavant Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA USA Graphics Technology Division Hewlett Packard Company Fort Collins CO USA

The computer-aided fabrication environment (CAFE) is a software system being developed at MIT for use in the manufacture of integrated circuits. CAFE is intended to be used in all phases of process design, development, planning, and manufacturing of integrated-circuit wafers. The CAFE architectural framework supports a wide variety of software modules, including both development tools and online applications. The key components of the CAFE architecture are the data model and database schema, the process flow and wafer representations, the user interface, and the application programming and database interfaces. All CAFE application modules store and retrieve persistent data through a common database interface layer. Interface wrappers provide seamless, transparent integration of external tools and packages which have their own internal data formats.< >

关键词： Fabrication Application software Databases computer aided manufacturing Software systems Integrated circuit manufacture computer integrated manufacturing Process design Process planning Manufacturing processes

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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 objective 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 tables in order to facilitate the comparative evaluation. The method is performed within a computer-based format which allows parametric sensitivity analysis of several variables 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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Performance of APN guidance law in a two dimensional aerial engagement scenario

Performance of APN guidance law in a two dimensional aerial ...

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IEEE National Conference on Aerospace and Electronics (NAECON)

作者： K.N. Swamy I.G. Sarma Advanced Technology Programme I.G.Sarma Professor of Computer Science and Automation Indian Institute of Science Bangalore India

In the available literature, the main advantage claimed for APN (augmented proportional navigation) is that it demands a progressively decreasing missile acceleration in the constant target maneuver situation, as opposed to an increasing missile acceleration for the more conventional PN guidance. This inference is mainly based on studies with one-dimensional models. Based on a two-dimensional model, the authors not only incorporate a more realistic target maneuver, but also consider the effect of target glint characterized by correlated noise. The missile acceleration and the miss-distance induced by target maneuver and glint are the two features of performance investigated. In a deterministic study, with target maneuver initiation occurring at various points in time, the acceleration profiles resemble the ones obtained from a linear quadratic tracking formulation of the guidance problem. The results indicate that there is a considerable improvement in the miss distance performance over PN, for maneuvers which are initiated when the relative separation is small.< >

关键词： Acceleration Missiles Navigation White noise Delay estimation computer science Automation Target tracking Low pass filters Filtering

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Nick Experimentation: Selected Results Concerning Effectiveness of Meeting Support technology

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Journal of Management Information Systems 1989年第3期6卷 7-24页

作者： Ellis, Clarence A. Rein, Gail L. Jarvenpaa, Sirkka L. Senior member of the technical staff Software Technology Program Microelectronics and Computer Technology Corporation (MCC) Adjunct professor University of Texas Member National Science Foundation Chairman ACM Special Interest Group on Office Information Systems Member of the technical staff Software Technology Program Microelectronics and Computer Technology Corporation (MCC) Assistant Professor Department of Management Science and Information Systems College of Business University of Texas

The Nick Summer Experiment was an empirical study undertaken to explore and increase the understanding of the use of prototype meeting support technology by software design teams working on high-level design problems. Three teams of designers (seven MCC researchers per team) were observed and videotaped while participating in 27 one-hour, face-to-face design meetings in both the electronic meeting room and in a conventional meeting room. The Nick support technologies explicitly aided the affective social meeting structures, as well as the rational task-oriented processes. Analysis of the experimental data revealed some gains in meeting effectiveness and quality from use of the Nick meeting support technologies. The 'subchannel' (messaging facility on the electronic workstations) emerged as a potentially effective way for participants to attain more equality and to influence the direction of the meetings. The electronic blackboard helped to increase group focus and attention on completing the task. [ABSTRACT FROM AUTHOR]

关键词： decision rooms electronic blackboard Electronic meetings electronic messaging

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CLEER - AN AI-SYSTEM DEVELOPED TO ASSIST EQUIPMENT ARRANGEMENTS ON WARSHIPS

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NAVAL ENGINEERS JOURNAL 1989年第3期101卷 127-137页

作者： ZHOU, HH SILVERMAN, BG SIMKOL, J Dr. H. Harry Zhou:is a research professor at the Institute for Artificial Intelligence of The George Washington University. Dr. Zhou received his master's degree and Ph.D. in computer science from Vanderbilt University in 1984 and 1987 respectively. He did his dissertation in the fields of artificial intelligence analogical reasoning and machine learning. His research interests include: classifier systems genetic algorithms learning by analogy inductive learning adaptive expert systems automated knowledge acquisition and adaption. He is also interested in data base design programming languages mental modeling and software engineering. Dr. Barry G. Silverman:is director of the Institute for Artificial Intelligence and a professor at the Engineering Administration Department of The George Washington University. He is also president of IntelliTek Inc. an AI consulting firm. Dr. Silverman received the B.S.E. M.S.E. and Ph.D. degrees from the University of Pennsylvania. He has been a principal developer of four generic AI products as well as eight AI applications. Since 1979 he has written over 100 papers and reports on these AI efforts. Joel Simkol:is a research scientist currently engaged in designing expert system architectures to support electronic warfare vulnerability analyses threat assessments shipboard topside antenna arrangements and C3countermeasures employment. Mr. Simkol's work in applying expert systems technology to electromagnetic interference and to spectrum management has generated increased interest and participation from all branches of government agencies.

This paper describes a modularized AI system being built to help improve electromagnetic compatibility (EMC) among shipboard topside equipment and their associated systems. CLEER is intended to act as an easy to use integrator of existing expert knowledge and pre-existing data bases and large scale analytical models. Due to these interfaces; to the need for portability of the software; and to artificial intelligence related design requirements (such as the need for spatial reasoning, expert data base management, model base management, track-based reasoning, and analogical (similar ship) reasoning) it was realized that traditional expert system shells would be inappropriate, although relatively off-the-shelf AI technology could be incorporated. In the same vein, the rapid prototyping approach to expert system design and knowledge engineering was not pursued in favor of a rigorous systems engineering methodology. The critical design decisions affecting CLEER's development are summarized in this paper along with lessons learned to date all in terms of “how,” “why,” and “when” specific features are being developed.

关键词： Artificial Intelligence

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ESTIMATION OF STRUCTURAL SERVICE LIFE OF SHIPS

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NAVAL ENGINEERS JOURNAL 1989年第3期101卷 156-166页

作者： AYYUB, BM WHITE, GJ PURCELL, ES P.E. 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 and design simulation and construction engineering. He is engaged in research work involving structural reliability bridges marine structures and mathematical modeling using the theories of probability statistics and fuzzy sets. His research work is sponsored by the National Transportation Safety Board the National Science Foundation the U.S. Coast Guard the State of Maryland and the University of Maryland. Dr. Ayyub is a member of ASNE the American Society of Civil Engineers (ASCE) the American Concrete Institute (ACI) the Committee on Forensic Engineering of ASCE and the Committee on Structural Safety of ACI. He is the author of more than three dozen publications in national and international journals conference proceedings and reports. Dr. Ayyub received the ASNE “Jimmie” Hamilton Award for 1985 and the ASCE “Outstanding Research Oriented Paper” in the Journal of Water Resources Planning and Management for 1987. Gregory J. White:is an associate professor of naval architecture at the U.S. Naval Academy. He received his B.S. degree in 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 a lieutenant commande

A methodology for the structural life assessment of a ship's structure is suggested. The methodology is based on probabilistic analysis using reliability concepts and the statistics of extremes. In this approach, the estimation of structural life expectancy is based on selected failure modes. All possible failure modes of the ship must be investigated and the most likely paths to structural failure identified. For the purpose of illustration two failure modes are considered in this study. They are plate plastic deformation and fatigue cracking. Structural life based on these two failure modes is determined for an example vessel. The methodology determines the probability of failure of the ship's structural components according to the identified failure modes as a function of time. The results can be interpreted as the cumulative probability distribution function (CDF) of structural life. Due to the unknown level of statistical correlation between failure modes, limits or bounds on the CDF of the structural life are established. The limits correspond to the extreme cases of fully correlated and independent failure modes. The CDFs of structural life are determined for two inspection strategies; namely, inspection every year and inspection every two years with a warranty inspection at the end of the first year. The meaning of the results for the case investigated in this study is that, for example, given an inspection strategy of two years and a desired life of 15 years, there is a 72% chance that the vessel will not experience enough partial damage‘ in the failure modes identified to constitute reaching the “end of structural life” as defined.

关键词： Ships

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Capacity Expansion for Information Flow Distribution in Multi-Path computer Communication Networks

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Journal of Management Information Systems 1988年第2期5卷 57-70页

作者： Vladimir Zwass Boris Veroy Professor of Computer Science Fairleigh Dickinson University. Professor of Computer Science New Jersey Institute of Technology

In the distributed processing environment characteristic of the management information systems of today, a need to superimpose an additional information flow onto an existing computer communication network arises frequently. The situation may result from a company's expanding needs for communication over its private or a shared network, or because a new user company is joining an existing shared network. In order to accommodate the new information flow without negatively affecting the waiting times for the previously contracted communications, network capacity may have to be expanded. We present an algorithmic method for least-cost capacity expansion of a set of network paths preselected to carry the incremental information flows. Owing to the insights gained as a result of extensive computational experiments, we then provide a simplified technique applicable to a broad class of cases. Polynomial time complexity of the algorithms included in the presented methodology points to its practicality.

关键词： Algorithms computer networking Dynamic programming Cost functions Information flow Average total cost Capacity costs Information storage and retrieval systems Network access lines Optimal solutions

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Convected activation profiles and the measurement of visual motion

Convected activation profiles and the measurement of visual ...

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Conference on computer Vision and Pattern Recognition (CVPR)

作者： A.M. Waxman J. Wu F. Bergholm Laboratory for Sensory Robotics College of Engineering Boston University Boston MA USA Computer Vision and Graphics Laboratory Department of Numerical Analysis and Computing Science Royal Institute of Technology Stockholm Sweden

A method is developed for the measurement of short-range visual motion in image sequences, making use of the motion of image features such as edges and points. Each feature generates a Gaussian activation profile in a spatiotemporal neighborhood of specified scale around the feature itself; this profile is then convected with motion of the feature. The authors show that image velocity estimates can be obtained from such dynamic activation profiles using a modification of familiar gradient techniques. The resulting estimators can be formulated in terms of simple ratios of spatiotemporal filters (i.e. receptive fields) convolved with image feature maps. A family of activation profiles of varying scale must be utilized to cover a range of possible image velocities. They suggest a characteristic speed normalization of the estimate obtained from each filter in order to decide which estimate is to be accepted. They formulate the velocity estimators for dynamic edges in 1-D and 2-D image sequences, as well as that for dynamic feature points in 2-D image sequences.< >

关键词： Motion measurement Image sequences Motion analysis Filters Laboratories computer vision Robot sensing systems Educational institutions computer graphics Numerical analysis

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Embedding a Point-to-Point Network in the Expansion of Infrastructure for Information Systems

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Journal of Management Information Systems 1987年第3期4卷 50-63页

作者： Veroy, Boris Zwass, Vladimir Professor of Computer Science New Jersey Institute of Technology. Professor of computer Science Fairleigh Dickinson University

Long-term evolution of management information systems toward distributed processing, accompanied of late by the development of inter-organizational systems, has posed increasing demands on the networking infrastructure. Within this framework, point-to-point data communication over a network composed of various media remains the most frequent communication mode. With a large base of network infrastructure in place, the need for incremental capacity increase due to new users who join existing networks has become a recurring problem. Accommodation of new users without downgrading the quality of service that has been provided to existing users requires network capacity expansion. A method is presented for computing the least-cost expansion of link capacities (defined as the number of lines in a link) on a point-to-point path in a network, subject to the constraint on the grade of service. A polynomial-time numerical algorithm is provided, along with the results of computer experiments. [ABSTRACT FROM AUTHOR]

关键词： capacity expansion Inter-organizational systems multi-link networks network expansion point-to-point networks.

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