Change is one of the most significant parameters in our society. Designers are amongst the primary change agents for any society. As a consequence design is an important research topic in engineering and architecture and related disciplines, since design is not only a means of change but is also one of the keystones to economic competitiveness and the fundamental precursor to manufacturing. The development of computational models founded on the artificial intelligence paradigm has provided an impetus for much of current design research -both computational and cognitive. These forms of design research have only been carried out in the last decade or so and in the temporal sense they are still immature. Notwithstanding this immaturity, noticeable advances have been made both in extending our understanding of design and in developing tools based on that understanding. Whilst many researchers in the field of artificial intelligence in design utilise ideas about how humans design as one source of concepts there is normally no attempt to model human designers. Rather the results of the research presented in this volume demonstrate approaches to increasing our understanding of design as a process.

Synthesis of Finite State Machines: Logic Optimization is the second in a set of two monographs devoted to the synthesis of Finite State Machines (FSMs). The first volume, Synthesis of Finite State Machines: Functional Optimization, addresses functional optimization, whereas this one addresses logic optimization. The result of functional optimization is a symbolic description of an FSM which represents a sequential function chosen from a collection of permissible candidates. Logic optimization is the body of techniques for converting a symbolic description of an FSM into a hardware implementation. The mapping of a given symbolic representation into a two-valued logic implementation is called state encoding (or state assignment) and it impacts heavily area, speed, testability and power consumption of the realized circuit. The first part of the book introduces the relevant background, presents results previously scattered in the literature on the computational complexity of encoding problems, and surveys in depth old and new approaches to encoding in logic synthesis. The second part of the book presents two main results about symbolic minimization; a new procedure to find minimal two-level symbolic covers, under face, dominance and disjunctive constraints, and a unified frame to check encodability of encoding constraints and find codes of minimum length that satisfy them. The third part of the book introduces generalized prime implicants (GPIs), which are the counterpart, in symbolic minimization of two-level logic, to prime implicants in two-valued two-level minimization. GPIs enable the design of an exact procedure for two-level symbolic minimization, based on a covering step which is complicated by the need to guarantee encodability of the final cover. A new efficient algorithm to verify encodability of a selected cover is presented. If a cover is not encodable, it is shown how to augment it minimally until an encodable superset of GPIs is determined. To handle encodability the authors have extended the frame to satisfy encoding constraints presented in the second part. The covering problems generated in the minimization of GPIs tend to be very large. Recently large covering problems have been attacked successfully by representing the covering table with binary decision diagrams (BDD). In the fourth part of the book the authors introduce such techniques and extend them to the case of the implicit minimization of GPIs, where the encodability and augmentation steps are also performed implicitly. Synthesis of Finite State Machines: Logic Optimization will be of interest to researchers and professional engineers who work in the area of computer-aided design of integrated circuits.

A Practical Guide to Analog Behavioral Modeling for IC System Design presents a methodology for abstracting an IC system so that the designer can gain a macroscopic view of how sub-systems interact, as well as verify system functionality in various applications before committing to a design. This will prevent problems that may be caused late in the design-cycle by incompatibilities between the individual blocks that comprise the overall system. This book will focus on the techniques of modelling IC systems through analog behavioral modeling and simulation. It will investigate a practical approach by which designers can put together these systems to analyze topological and architectural issues to optimize IC system performance.Highlights: * Discussions on modeling and simulation from SPICE to behavioral simulators * Comparison of various hardware description languages and a discussion on the effects of language standardization * Explanation on how to reduce time-to-market by decreasing design-cycle time through modeling and simulation * Contains more than 25 building block examples that can be used to construct mixed-signal IC system models * Analysis of 4 different IC systems using various levels of model detail This book is intended for the practicing engineer who would like to gain practical knowledge in applications of analog behavioral modelling for IC system design.

Control networks span a wide range of application areas. These networks are put into action in the `Digital Home', industrial applications, commercial buildings, transportation systems, gas stations, security systems, and they are found in most instances where smart sensors and smart actuators are used to exchange information. The authors of this volume provide an overview of various control network protocols and discuss LonTalk (R) protocol, Neuron (R) chip, programming model, network structures, network management, interoperability between nodes, application profiles, development and maintenance tools, performance analysis, and standardization activities. Open Control Networks: LonWorks/EIA 709 Technology will be an important resource for advanced students of control systems and embedded systems, engineers designing distributed networks, systems designers and architects, and others developing smart buildings and intelligent transportation systems.

The Current state of expectations is that Computer Integrated Manufacturing (CIM) will ulti mately determine the industrial growth of world nations within the next few decades. Computer Aided Design (CAD), Computer Aided Manufacturing (CAM), Flexible Manufacturing Systems (FMS), Robotics together with Knowledge and Information Based Systems (KIBS) and Com munication Networks are expected to develop to a mature state to respond effectively to the managerial requirements of the factories of the future that are becoming highly integrated and complex. CIM represents a new production approach which will allow the factories to deliver a high variety of products at a low cost and with short production cycles. The new technologies for CIM are needed to develop manufacturing environments that are smarter, faster, close-cou pled, integrated, optimized, and flexible. Sophistication and a high degree of specialization in materials science, artificial intelligence, communications technology and knowledge-information science techniques are needed among others for the development of realizable and workable CIM systems that are capable of adjusting to volatile markets. CIM factories are to allow the production of a wide variety of similar products in small batches through standard but multi mission oriented designs that accommodate flexibility with specialized software."

2 e This book describes principles, methods and tools that are common to computer applications for design tasks. CAD is considered in this book as a discipline that provides the required know-how in computer hardware and software, in systems analysis and in engineering methodology for specifying, designing, implementing, introducing, and using computer based systems for design purposes. The first chapter gives an impression of the book as a whole, and following chapters deal with the history and the components of CAD, the process aspect of CAD, CAD architecture, graphical devices and systems, CAD engineering methods, CAD data transfer, and application examples. The flood of new developments in the field and the success of the first edition of this book have led the authors to prepare this completely revised, updated and extended second edition. Extensive new material is included on computer graphics, implementation methodology and CAD data transfer; the material on graphics standards is updated. The book is aimed primarily at engineers who design or install CAD systems. It is also intended for students who seek a broad fundamental background in CAD.

What are the design or selection criteria for robots that will be capable of carrying out particular functions? How can robots and machines be installed in work locations to obtain maximum effectiveness? How can their programming be made easier? How can a work location be arranged so as to accommodate successfully automatic machines? Traditionally, these questions have only been answered as a result of long and exhaustive study, involving complex calculations and the use of many sketches and plans. Computers and interactive computer graphics provide the possibility of automation for this type of analysis, thus making the task of robot designers and users easier. This volume is concerned with mathematical modelling and graphics representation of robot performance (eg their fields of action, their performance index) as a function of their structure, mechanical parts and memory systems. Used in conjunction with operating specifications, such as movement programs and computer-aided design (CAD) data bases that describe parts or tools, these perform ance models can allow the potential of different robots or different models of the same type of robot to be compared, workstations to be organized efficiently, responses to be optimized, errors to be minimized and can make off-line programming by computer a real possibility. In the future, it is certain that the appearance of robots designed to monitor their own performances will allow applications and safety conditions to be considerably improved."

A spline is a thin flexible strip composed of a material such as bamboo or steel that can be bent to pass through or near given points in the plane, or in 3-space in a smooth manner. Mechanical engineers and drafting specialists find such (physical) splines useful in designing and in drawing plans for a wide variety of objects, such as for hulls of boats or for the bodies of automobiles where smooth curves need to be specified. These days, physi cal splines are largely replaced by computer software that can compute the desired curves (with appropriate encouragment). The same mathematical ideas used for computing "spline" curves can be extended to allow us to compute "spline" surfaces. The application ofthese mathematical ideas is rather widespread. Spline functions are central to computer graphics disciplines. Spline curves and surfaces are used in computer graphics renderings for both real and imagi nary objects. Computer-aided-design (CAD) systems depend on algorithms for computing spline functions, and splines are used in numerical analysis and statistics. Thus the construction of movies and computer games trav els side-by-side with the art of automobile design, sail construction, and architecture; and statisticians and applied mathematicians use splines as everyday computational tools, often divorced from graphic images."

The success of VHDL since it has been balloted in 1987 as an IEEE standard may look incomprehensible to the large population of hardware designers, who had never heared of Hardware Description Languages before (for at least 90% of them), as well as to the few hundreds of specialists who had been working on these languages for a long time (25 years for some of them). Until 1988, only a very small subset of designers, in a few large companies, were used to describe their designs using a proprietary HDL, or sometimes a HDL inherited from a University when some software environment happened to be developped around it, allowing usability by third parties. A number of benefits were definitely recognized to this practice, such as functional verification of a specification through simulation, first performance evaluation of a tentative design, and sometimes automatic microprogram generation or even automatic high level synthesis. As there was apparently no market for HDL's, the ECAD vendors did not care about them, start-up companies were seldom able to survive in this area, and large users of proprietary tools were spending more and more people and money just to maintain their internal system.

There is much excitement in the design and verification community about assertion-based design. The question is, who should study assertion-based design? The emphatic answer is, both design and verification engineers. What may be unintuitive to many design engineers is that adding assertions to RTL code will actually reduce design time, while better documenting design intent. Every design engineer should read this book! Design engineers that add assertions to their design will not only reduce the time needed to complete a design, they will also reduce the number of interruptions from verification engineers to answer questions about design intent and to address verification suite mistakes. With design assertions in place, the majority of the interruptions from verification engineers will be related to actual design problems and the error feedback provided will be more useful to help identify design flaws. A design engineer who does not add assertions to the RTL code will spend more time with verification engineers explaining the design functionality and intended interface requirements, knowledge that is needed by the verification engineer to complete the job of testing the design.

Every pioneer takes large risks, hoping that the new frontier he seeks will provide the benefits of independence and good fortune. Don Tapscott is such a pioneer in the area of office automation. He has been a true pioneer, having entered the field in its early days and taken the risk of working not in technol ogy, which was fashionable, but in the field of the problems of organizations, which was less fashionable, but in many ways more important. The utilization of computers for data processing, accounting, inventory, and other "bread and butter" applications is now well entrenched in our society and culture. The process of designing such systems tends to focus on the needs of the company and the constraints of the equipment, leading to efficient systems with little tolerance for the variety of people who must use or interface with them. Within the office automation area, these methods do not work nearly as well. The frequency and amount of human interaction in the office environment, and the wide variety of situations and reactions there in, demands a different design methodology."

Designing is one of the foundations for change in our society. It is a fundamental precursor to manufacturing, fabrication and construction. Design research aims to develop an understanding of designing and to produce models of designing that can be used to aid designing. The papers in this volume are from the Sixth International Conference on Artificial Intelligence in Design (AID'00) held in June 2000, in Worcester, Massachusetts, USA. They represent the state of the art and the cutting edge of research and development in this field, and demonstrate both the depth and breadth of the artificial intelligence paradigm in design. They point the way for the development of advanced computer-based tools to aid designers, and describe advances in both theory and application. This volume will be of particular interest to researchers, developers, and users of advanced computer systems in design.

Computer-AidedInnovation(CAI)isayoungdomaininthearrayofCAxte- nologies. ThegoalofCAIistosupportengineersandenterprisesthroughoutthe completeinnovationprocess. AlthoughsomeexistingideasandconceptsofCAI focus on assisting product designers in their creative stage, a more compreh- sive vision conceives CAI systems beginning at the creative stage of perceiving business opportunities and customer demands, then helping in developing - ventions and, further on, providing help up to the point of turning inventions into successful innovations in the market. Following the track of the last two successful CAI conferences held in 2005, in Germany, and 2007 in USA, the ThirdIFIPWorkingConferenceonComputer-AidedInnovation(CAI)washeld in Harbin, China, and attractedparticipants fromacademia and industry. This workingconferencecontinuedthe traditionofstronglylinkingacademicand- dustrymembers. Theconferencehadseveralparallelsessions, andeightkeynote sessions. Over 100 participants attended the conference. Some famous scholars wereinvited askeynotespeakers. I would liketo takethe opportunityto thank all the authors for their quality research, the international Program Comm- teemembersfortheirsupportinreviewingthepapers, andthelocalOrganizing Committeefortheirpreparationoftheconference. Furthermore, IthanktheC- neseNaturalScienceFoundation, theDepartmentofScienceandTechnologyof HeilongjiangProvincialGovernment, theInstituteofDesignforInnovation, and Hebei University of Technology, for their ?nancial support of the conference. I wouldalsoliketothankZhuLin, YaoYihang, XueGuiying, andCaoGuozhong for their signi?cantcontributions towardthe successof the conference. August 2009 Runhua Tan Organization TheThirdIFIPWorkingConferenceonComputer-AidedInnovation(CAI)was organized by Hebei University of Technology and the Department of Science andTechnologyofHeilongjiangProvincialGovernmentincooperationwiththe National Natural Science Foundationof China. Program Committee Conference Chair Runhua Tan, (Hebei University ofTechnology, China) Noel Leon(ITESM, Campus Monterrey, Mexico) OrganizingChair T. S. Yang (Department ofScience and Technologyof Heilongjiang Provincial Government, China) Referees T. Arciszewski(USA) Y. Li (China) M. Ashtiani (USA) H. Liu (China) G. Cascini(Italy) M. L. Maher (Australia) D. Cavalucci (France) M. B. Mc Grath(USA) R. De Guio(France) G. Mukundan (USA) S. K. Cho (USA) G. Olling (USA) S. Finger (USA) J. Ovtcharova(Germany) J. Gero(Australia) E. Schueler-Hainsch(Germany) C. Gundlach(Germ

The purpose of computer vision is to make computers capable of understanding environments from visual information. Computer vision has been an interesting theme in the field of artificial intelligence. It involves a variety of intelligent information processing: both pattern processing for extraction of meaningful symbols from visual information and symbol processing for determining what the symbols represent. The term "3D computer vision" is used if visual information has to be interpreted as three-dimensional scenes. 3D computer vision is more challenging because objects are seen from limited directions and some objects are occluded by others. In 1980, the author wrote a book "Computer Vision" in Japanese to introduce an interesting new approach to visual information processing developed so far. Since then computer vision has made remarkable progress: various rangefinders have become available, new methods have been developed to obtain 3D informa tion, knowledge representation frameworks have been proposed, geometric models which were developed in CAD/CAM have been used for computer vision, and so on. The progress in computer vision technology has made it possible to understand more complex 3 D scenes. There is an increasing demand for 3D computer vision. In factories, for example, automatic assembly and inspection can be realized with fewer con straints than conventional ones which employ two-dimensional computer vision."

Software Diversity is one of the fault-tolerance means to achieve dependable systems. In this volume, some experimental systems as well as real-life applications of software diversity are presented. The history, the current state-of-the-art and future perspectives are given. Although this technique is used quite successfully in industrial applications, further research is necessary to solve some open questions. We hope to report on new results and applications in another volume of this series within some years. Acknowledgements The idea of the workshop was put forward by the chairpersons of IFIP WG lOA, J. -c. Laprie, J. F. Meyer and Y. Tohma, in January 1986, and the edi tor of this volume was asked to organize the workshop. This volume was edited with the assistance of the editors of the series, A. AviZienis, H. Kopetz and J. -C. Laprie, who also had the function of reviewers. Karlsruhe, October 1987 U. Voges, Editor Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1. Introduction U. Voges 2. Railway Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 ERICSSON Safety System for Railway Control . . . . . . . . . . . . . . . . . . 11 G. Hagelin 3. Nuclear Applications . . . . . . . . . . . . . . . . . . . . . . 23 Use of Diversity in Experimental Reactor Safety Systems . 29 U. Voges The PODS Diversity Experiment . 51 P. G. Bishop 4. Flight Applications . . . . . . . . . . . . . . . . . . . . . . . . . 85 AIRBUS and ATR System Architecture and Specification. . 95 P. Traverse 5. University Research . . . . . . . . . . . . . . . . . . . 105 Tolerating Software Design Faults in a Command and Control System . . . . . . . . . . . . . . . . . . . . . . 109 T. Anderson, P. A. Barrett, D. N. Halliwell, M. R. Moulding DEDIX 87 - A Supervisory System for Design Diversity Experiments at UCLA . . . . . . . . . . . . . . . . . ."

This fourth volume of Advances in Computer Graphics gathers together a selection of the tutorials presented at the EUROGRAPHICS annual conference in Nice, France, Septem ber 1988. The six contributions cover various disciplines in Computer Graphics, giving either an in-depth view of a specific topic or an updated overview of a large area. Chapter 1, Object-oriented Computer Graphics, introduces the concepts of object ori ented programming and shows how they can be applied in different fields of Computer Graphics, such as modelling, animation and user interface design. Finally, it provides an extensive bibliography for those who want to know more about this fast growing subject. Chapter 2, Projective Geometry and Computer Graphics, is a detailed presentation of the mathematics of projective geometry, which serves as the mathematical background for all graphic packages, including GKS, GKS-3D and PRIGS. This useful paper gives in a single document information formerly scattered throughout the literature and can be used as a reference for those who have to implement graphics and CAD systems. Chapter 3, GKS-3D and PHIGS: Theory and Practice, describes both standards for 3D graphics, and shows how each of them is better adapted in different typical applications. It provides answers to those who have to choose a basic 3D graphics library for their developments, or to people who have to define their future policy for graphics.

Physical Design for Multichip Modules collects together a large body of important research work that has been conducted in recent years in the area of Multichip Module (MCM) design. The material consists of a survey of published results as well as original work by the authors. All major aspects of MCM physical design are discussed, including interconnect analysis and modeling, system partitioning and placement, and multilayer routing. For readers unfamiliar with MCMs, this book presents an overview of the different MCM technologies available today. An in-depth discussion of various recent approaches to interconnect analysis are also presented. Remaining chapters discuss the problems of partitioning, placement, and multilayer routing, with an emphasis on timing performance. For the first time, data from a wide range of sources is integrated to present a clear picture of a new, challenging and very important research area. For students and researchers looking for interesting research topics, open problems and suggestions for further research are clearly stated.Points of interest include: * Clear overview of MCM technology and its relationship to physical design; * Emphasis on performance-driven design, with a chapter devoted to recent techniques for rapid performance analysis and modeling of MCM interconnects; * Different approaches to multilayer MCM routing collected together and compared for the first time; * Explanation of algorithms is not overly mathematical, yet is detailed enough to give readers a clear understanding of the approach; * Quantitative data provided wherever possible for comparison of different approaches; * A comprehensive list of references to recent literature on MCMs provided.

The rapid evolution and explosive growth of integrated circuit technology have impacted society more than any other technological development of the 20th century. Integrated circuits (ICs) are used universally and the expanding use of IC technology requires more accurate circuit analysis methods and tools, prompting the introduction of computers into the design process. The goal of this book is to build a firm foundation in the use of computer-assisted techniques for IC device and process design. Both practical and analytical viewpoints are stressed to give the reader the background necessary to appreciate CAD tools and to feel comfortable with their use. Technology CAD - Computer Simulation of IC Processes and Devices presents a unified discourse on process and device CAD as interrelated subjects, building on a wide range of experiences and applications of the SUPREM program. Chapter 1 focuses on the motivation for coupled process and device CAD. In Chapter 2 SUPREM III is introduced, and process CAD is discussed in terms of ion-implantation, impurity diffusion, and oxidation models.Chapter 3 introduces the Stanford device analysis program SEDAN III (SEmiconductor Device ANalysis). The next three chapters move into greater detail concerning device operating principles and analysis techniques. Chapter 4 reviews the classical formulation of pn junction theory and uses device analysis (SEDAN) both to evaluate some of the classical assumptions and to investigate the difficult problem of high level injection. Chapter 5 returns to MOS devices, reviews the first-order MOS theory, and introduces some important second-order effects. Chapter 6 considers the bipolar transistor. Chapter 7 considers the application of process simulation and device analysis to technology design. The BiCMOS process is selected as a useful design vehicle for two reasons. First, it allows the reader to pull together concepts from the entire book. Second, the inherent nature of BiCMOS technology offers real constraints and hence trade-offs which must be understood and accounted for.

Model Generation in Electronic Design covers a wide range of model applications and research. The book begins by describing a model generator to create component models. It goes on to discuss ASIC design and ASIC library generation. This section includes chapters on the requirements for developing and ASIC library, a case study in which VITAL is used to create such a library, and the analysis and description of the accuracy required in modeling interconnections in ASIC design. Other chapters describe the development of thermal models for electronic devices, the development of a set of model packages for VHDL floating point operations, a techniques for model validation and verification, and a tool for model encryption. Model Generation in Electronic Design is an essential update for users, vendors, model producers, technical managers, designers and researchers working in electronic design.

This book is the first issue of a EUROGRAPHICS publication series in the field of computer graphics, an important field of research and a versatile tool for various application areas. The availability of powerful hardware at an affordable price and the evolution of high standard software have led to a rapidly increas ing expansion of computer graphics and the penetration of compu ter graphics techniques and systems into a wide range of applica tion areas. This book series will cover state-of-the-art surveys as well as scientific contributions on specific areas of research and develop ment. The first book in the series contains the Tutorial Notes of the EUROGRAPHICS '83 conference, held in Zagreb, Yugoslavia, in September 1983. It covers four major aspects of computer graphics today: - The first part contains a detailed introduction into computer graphics, its concepts, its methods, its tools, and its devices. It gives an easy access for the newcomer to the field and it offers an overview of the state of the art in computer graphics. - The second part is devoted to interactive techniques. This is currently one of the most important fields of research in computer graphics. Important aspects of this research and its current state are reported. From the developments described here, in the near future powerful generally applicable user interface management systems are likely to evolve."

Computer Science Workbench is a monograph series which will provide you with an in-depth working knowledge of current developments in computer technology. Every volume in this series will deal with a topic of importance in computer science and elaborate on how you yourself can build systems related to the main theme. You will be able to develop a variety of systems, including computer software tools, computer gra phics, computer animation, database management systems, and compu ter-aided design and manufacturing systems. Computer Science Work bench represents an important new contribution in the field of practical computer technology. TOSIYASU L. KUNII Preface to the Second Edition Computer graphics is growing very rapidly; only computer animation grows faster. The first edition of the book Computer Animation: Theory and Practice was released in 1985. Four years later, computer animation has exploded. Conferences on computer animation have appeared and the topic is recognized in well-known journals as a leading theme. Computer-generated film festivals now exist in each country and several thousands of films are produced each year. From a commercial point of view, the computer animation market has grown considerably. TV logos are computer-made and more and more simulations use the technique of computer animation. What is the most fascinating is certainly the development of computer animation from a research point-of-view."

Large system complexities and operation under tight timing constraints in rapidly shrinking technologies have made it extremely important to ensure correct temporal behavior of modern-day digital circuits, both before and after fabrication. Research in (pre-fabrication) timing verification and (post-fabrication) delay fault testing has evolved along largely disjoint lines in spite of the fact that they share many basic concepts. A Unified Approach for Timing Verification and Delay Fault Testing applies concepts developed in the context of delay fault testing to path sensitization, which allows an accurate timing analysis mechanism to be developed. This path sensitization strategy is further applied for efficient delay fault diagnosis and delay fault coverage estimation. A new path sensitization strategy called Signal Stabilization Time Analysis (SSTA) has been developed based on the fact that primitive PDFs determine the stabilization time of the circuit outputs. This analysis has been used to develop a feasible method of identifying the primitive PDFs in a general multi-level logic circuit. An approach to determine the maximum circuit delay using this primitive PDF identification mechanism is also presented. The Primitive PDF Identification-based Timing Analysis (PITA) approach is proved to determine the maximum floating mode circuit delay exactly under any component delay model, and provides several advantages over previously floating mode timing analyzers. A framework for the diagnosis of circuit failures caused by distributed path delay faults is also presented. A metric to quantify the diagnosability of a path delay fault for a test is also proposed. Finally, the book presents a very realistic metric for delay fault coverage which accounts for delay fault size distributions and is applicable to any delay fault model. A Unified Approach for Timing Verification and Delay Fault Testing will be of interest to university and industry researchers in timing analysis and delay fault testing as well as EDA tool development engineers and design verification engineers dealing with timing issues in ULSI circuits. The book should also be of interest to digital designers and others interested in knowing the state of the art in timing verification and delay fault testing.

This book is an extension of one author's doctoral thesis on the false path problem. The work was begun with the idea of systematizing the various solutions to the false path problem that had been proposed in the literature, with a view to determining the computational expense of each versus the gain in accuracy. However, it became clear that some of the proposed approaches in the literature were wrong in that they under estimated the critical delay of some circuits under reasonable conditions. Further, some other approaches were vague and so of questionable accu racy. The focus of the research therefore shifted to establishing a theory (the viability theory) and algorithms which could be guaranteed correct, and then using this theory to justify (or not) existing approaches. Our quest was successful enough to justify presenting the full details in a book. After it was discovered that some existing approaches were wrong, it became apparent that the root of the difficulties lay in the attempts to balance computational efficiency and accuracy by separating the tempo ral and logical (or functional) behaviour of combinational circuits. This separation is the fruit of several unstated assumptions; first, that one can ignore the logical relationships of wires in a network when considering timing behaviour, and, second, that one can ignore timing considerations when attempting to discover the values of wires in a circuit."

Computer-aided design has come of age in the magnetic devices industry. From its early beginnings in the 1960s, when the precision needs of the experimental physics community first created a need for computational aids to magnet design, CAD software has grown to occupy an important spot in the industrial designer's tool kit. Numerous commercial CAD systems are now available for magnetics work, and many more software packages are used in-house by large industrial firms. While their capabilities vary, all these software systems share a very substantial common core of both methodology and objec tives. The present need, particularly in medium-sized and nonspecialist firms, is for an understanding of how to make effective use of these new and immensely powerful tools: what approximations are inherent in the methods, what quantities can be calculated, and how to relate the com puted results to the needs of the designer. These new analysis techniques profoundly affect the designer's approach to problems, since the analytic tools available exert a strong influence on the conceptual models people build, and these in turn dictate the manner in which they formulate prob lems. The impact of CAD is just beginning to be felt industrially, and the authors believe this is an early, but not too early, time to collect together some of the experience which has now accumulated among industrial and research users of magnetics analysis systems."

Object-oriented systems have gained a great deal of popularity recently and their application to graphics has been very successful. This book documents a number of recent advances and indicates numerous areas of current research. The purpose of the book is: - to demonstrate the extraordinary practical utility of object-oriented methods in computer graphics (including user interfaces, image synthesis, CAD), - to examine outstanding research issues in the field of object-oriented graphics, and in particular to investi- gate extensions and shortcomings of the methodology when applied to computer graphics. Papers included in the book extend existing object-oriented graphical techniques, such as Smalltalk's "model view controller" or "constraints," introduce the use of complex and persistent objects in graphics, and give approaches to direct manipulation interfaces. The reader is presented with an in-depth treatment of a number of significant existing graphics systems, both for user interfaces and for image synthesis. There are theoretical surveys and chapters pointing to new directions in the broad field of computer graphics. Computer language scientists will find a useful critique of object-oriented language constructs and suggested ways to extend object-oriented theory.