TAPSOFT '89 is the Third International Joint Conference on Theory and Practice of Software Development held in Barcelona, Spain, March 13-17, 1989. The conference consissted of three parts: - Advanced Seminar on Foundations of Innovative Software Development - Colloquium on Trees in Algebra and Programming (CAAP '89) - Colloquium on Current Issues in Programming Languages (CCIPL) The TAPSOFT '89 Conference Proceedings are published in two volumes. The first volume includes the papers from CAAP plus the more theoretical ones of the invited papers. The second volume comprises the papers from CCIPL and the invited papers more relevant to current issues in programming languages.

The 4th Bad Honnef Conference on Stochastic Differential Systems highlighted recent advances in the areas of stochastic control and filtering theory as well as stochastic analysis. Special emphasis was put on the use of adaptive methods in stochastic systems analysis and on the theory of random fields, both very active fields of current research. There were six survey lectures, two of them on adaptive control of linear stochastic systems (Kumar, Lai), two on problems in stochastic analysis and random fields, (Surgailis, Wong) and one on singular perturbations in nonlinear filtering (Bensoussan). In addition, 37 research papers pertaining to the main topics of the conference were presented.

This volume presents the proceedings of the 14th International Workshop on Graph-Theoretic Concepts in Computer Science (WG '88), held from June 15 to 17, 1988 in Amsterdam, The Netherlands. It contains 31 papers on new or current developments in the area of graph-based algorithms. The topics covered include e.g. structural graph theory, parallel graph algorithms, graph-based modeling (in database theory and VLSI), computational geometry and applied graph theory. The book contains the revised versions of all the papers presented at the workshop. The revisions are based on comments and suggestions received by the authors during and after the workshop.

This volume contains the proceedings of the 8th Conference on Foundations of Software Technology and Theoretical Computer Science held in Pune, India, on December 21-23, 1988. This internationally well-established Indian conference series provides a forum for actively investigating the interface between theory and practice of Software Science. It also gives an annual occasion for interaction between active research communities in India and abroad. Besides attractive invited papers the volume contains carefully reviewed submitted papers on the following topics: Automata and Formal Languages, Graph Algorithms and Geometric Algorithms, Distributed Computing, Parallel Algorithms, Database Theory, Logic Programming, Programming Methodology, Theory of Algorithms, Semantics and Complexity.

This volume contains the proceedings of CONCURRENCY 88, an international conference on formal methods for distributed systems, held October 18-19, 1988 in Hamburg. CONCURRENCY 88 responded to great interest in the field of formal methods as a means of mastering the complexity of distributed systems. In addition, the impulse was determined by the fact that the various methodological approaches, such as constructive or property oriented methods, have not had an extensive comparative analysis nor have they been investigated with respect to their possible integration and their practical implications. The following topics were addressed: Specification Languages, Models for Distributed Systems, Verification and Validation, Knowledge Based Protocol Modeling, Fault Tolerance, Distributed Databases. The volume contains 12 invited papers and 14 contributions selected by the program committee. They were presented by authors from Austria, the Federal Republic of Germany, France, Israel, Italy, the Netherlands, the United Kingdom and the United States.

The idea behind the series of volumes Advances in Petri Nets is to present to the general computer science community recent results which are the most representative and significant for the development in this area. The main source for the papers for "Advances" are the annual "European Workshops on Applications and Theory of Petri Nets"; the "best" papers from the latest workshops are considered for the series, i.e. they are reviewed again and revised or extended accordingly. In addition to the workshop papers, the "Advances" also present invited papers submitted directly for publication. The present volume Advances in Petri Nets 1988 covers the 8th "European Workshop on Applications and Theory of Petri Nets" held in Zaragoza, Spain in June 1987. It also contains a survey on decidability questions for classes of FIFO nets by A. Finkel and L.E. Rosier.

This volume contains the papers which were presented at the second workshop "Computer Science Logic" held in Duisburg, FRG, October 3-7, 1988. These proceedings cover a wide range of topics both from theoretical and applied areas of computer science. More specifically, the papers deal with problems arising at the border of logic and computer science: e.g. in complexity, data base theory, logic programming, artificial intelligence, and concurrency. The volume should be of interest to all logicians and computer scientists working in the above fields.

TAPSOFT '89 is the Third International Joint Conference on Theory and Practice of Software Development held in Barcelona, Spain, March 13-17, 1989. The conference consisted of three parts: - Advanced Seminar on Foundations of Innovative Software Development - Colloquium on Trees in Algebra and Programming (CAAP '89) - Colloquium on Current Issues in Programming Languages (CCIPL) The TAPSOFT '89 Conference Proceedings are published in two volumes. The first volume includes the papers from CAAP plus the more theoretical ones of the invited papers. The second volume comprises the papers from CCIPL and the invited papers more relevant to current issues in programming languages.

It is already a tradition that conferences on operations research are organized by the Mathematisches Forschungsinstitut in Oberwolfach/Germany. The mean point of the 1987 conference was to discuss recentl.v developed methods in optimization theory derived from various fields of mathematics. On the other hand, the practical use of results in operations research is very important. In the last few years* essenti.al progress in this direction was made at the International Insti- tute for Applied Systems Analysis (IIASA) at Laxenburg/Austria. Therefore a three days workshop on Advanced Computation Techniques, Parallel Processing and Optimi- zation organized by IIASA and the University of Karlsruhe immediately followed the Oberwolfach Conference. This volume contains selected pape~s which have been presented at one of these conferences. It:is divided into five sections based on the above topics: I. Algorithms and Optimization Methods II. Optimization and Parallel Processing III. Graph Theory and Scheduling IV. Differential Equations and Operator Theory V. Applications. We would like to thank the director of the Mathematisches Forschungsinstitut Oberwolfach Prof. Dr. M. Barner and the International Institute for Applied Systems Analysis, particularly Prof. Dr. V. Kaftanov, and also to the director of the Computer Center of the University of Karlsruhe Prof. Dr. A. Schreiner for their support in organizing these conferences. We also appreciate the excellent coopera- tion of Springer Verlag. We also thank Dr. P. Recht, Dr. D. Solte and Dr. K. Wieder as well as*Mrs.

This volume contains the presentations of the Fifth Symposium on Theoretical Aspects of Computer Science (STACS 88) held at the University of Bordeaux, February 11-13, 1988. In addition to papers presented in the regular program the volume contains abstracts of software systems demonstrations which were included in this conference series in order to show applications of research results in theoretical computer science. The papers are grouped into the following thematic sections: algorithms, complexity, formal languages, rewriting systems and abstract data types, graph grammars, distributed algorithms, geometrical algorithms, trace languages, semantics of parallelism.

This volume gives the proceedings of the Tenth Conference on Foundations of Software Technology and Theoretical Computer Science. These conferences are organized and run by the computer science research community in India, and their purpose is to provide a forum for professional interaction between members of this research community and their counterparts in different parts of the world. The volume includes four invited papers on: - reasoning about linear constraints using parametric queries, - the parallel evaluation of classes of circuits, - a theory of commonsense visual reasoning, - natural language processing, complexity theory and logic. The 26 submitted papers are organized into sections on logic, automata and formal languages, theory of programming, parallel algorithms, geometric algorithms, concurrency, distributed computing, and semantics.

The aim of the workshop was to discuss whether research on implementation of programming languages and research on logic programming can mutually benefit from each others results. The intention was to bring together researchers from both fields, especially those working in the area of their intersection. Problems such as formal specification of compilers and syntax-based editors, program analysis and program optimization have been traditionally studied by implementors of algorithmic languages and have resulted in a number of well-established notions, formalisms and techniques. At the same time, an increasing number of people use logic programming as a way of specifying compilers or other programming environment tools, taking advantage of the relatively high level of logic programming and the growing efficiency of Prolog implementations. On the other hand, research on logic programming raises the questions of analysis of logic programs and their optimization. These are motivated primarily by compiler construction for logic programs, by studies on the methodology of logic programming and by the attempts to amalgamate logic programming and functional programming. The purpose of the workshop is to review the techniques developed in one (or both) of the fields which could also be of some help in the other one and to facilitate the transfer of expertise. It seems important to compare notions used in both fields: showing similarities between them may prevent rediscovering results already known, while studying differences may contribute to the transfer of technology.

This monograph grew out of a combined effort to prove a conjecture concerning the characterization of Hamiltonian control systems in terms of their variational input-output behaviour. The main concepts and results of this monograph are contained in chapters 1 to 6. Chapter 0 gives a brief introduction to Hamiltonian control systems, with particular emphasis on the relations between physical and control theoretical notions. Indeed, the study of Hamiltonian control systems is one of the places where (theoretical) physics and systems and control theory meet. We conclude the monograph with chapter 7 discussing some possible extensions to the theory presented, as well as some open problems.

This volume describes recent research in graph reduction and related areas of functional and logic programming, as reported at a workshop in 1986. The papers are based on the presentations, and because the final versions were prepared after the workshop, they reflect some of the discussions as well. Some benefits of graph reduction can be found in these papers: - A mathematically elegant denotational semantics - Lazy evaluation, which avoids recomputation and makes programming with infinite data structures (such as streams) possible - A natural tasking model for fine-to-medium grain parallelism. The major topics covered are computational models for graph reduction, implementation of graph reduction on conventional architectures, specialized graph reduction architectures, resource control issues such as control of reduction order and garbage collection, performance modelling and simulation, treatment of arrays, and the relationship of graph reduction to logic programming.

The collection of papers published in this book was initially presented at the Workshop on Software Factories and Ada, held on Capri, May 26-30, 1986. The subject of the book is software development environments. Software development is treated from three viewpoints: methodologies, language issues and mechanisms. Of particular interest are the discussions of automation of the development process and the formalization of software development specifications. Several new methodologies are described, many of which are available on the commercial market. New is in particular the formalization of the design and development process. Interesting ideas are presented on planning the design process and on supporting project management by formal tools. The reader will find a variety of interesting methodologies and mechanisms that are operational. The book is suitable for readers interested in knowing in which direction programming environment research is moving.

This volume contains the proceedings of the Third Conference on Functional Programming Languages and Computer Architecture held in Portland, Oregon, September 14-16, 1987. This conference was a successor to two highly successful conferences on the same topics held at Wentworth, New Hampshire, in October 1981 and in Nancy, in September 1985. Papers were solicited on all aspects of functional languages and particularly implementation techniques for functional programming languages and computer architectures to support the efficient execution of functional programs. The contributions collected in this volume show that many issues regarding the implementation of Functional Programming Languages are now far better understood.

This volume contains the papers which were presented to the workshop "Computer-Science Logic" held in Karlsruhe on October 12-16, 1987. Traditionally Logic, or more specifically, Mathematical Logic splits into several subareas: Set Theory, Proof Theory, Recursion Theory, and Model Theory. In addition there is what sometimes is called Philosophical Logic which deals with topics like nonclassical logics and which for historical reasons has been developed mainly at philosphical departments rather than at mathematics institutions. Today Computer Science challenges Logic in a new way. The theoretical analysis of problems in Computer Science for intrinsic reasons has pointed back to Logic. A broad class of questions became visible which is of a basically logical nature. These questions are often related to some of the traditional disciplines of Logic but normally without being covered adequately by any of them. The novel and unifying aspect of this new branch of Logic is the algorithmic point of view which is based on experiences people had with computers. The aim of the "Computer-Science Logic" workshop and of this volume is to represent the richness of research activities in this field in the German-speaking countries and to point to their underlying general logical principles.

This volume contains abridged versions of most of the sectional talks and some invited lectures given at the International Conference on Fundamentals of Computation Theory held at Kazan State University, Kazan, USSR, June 22-26, 1987. The conference was the sixth in the series of FCT Conferences organized every odd year, and the first one to take place in the USSR. FCT '87 was organized by the Section of Discrete Mathematics of the Academy of Sciences in the USSR, the Moscow State University (Department of Discrete Mathematics), and the Kazan State University (Department of Theoretical Cybernetics). This volume contains selected contributions to the following fields: Mathematical Models of Computation, Synthesis and Complexity of Control Systems, Probabilistic Computations, Theory of Programming, Computer-Assisted Deduction. The volume reflects the fact that FCT '87 was organized in the USSR: A wide range of problems typical of research in Mathematical Cybernetics in the USSR is comprehensively represented.

The 1st International Conference on Supercomputing took place in Athens, Greece, June 8-12, 1987. The purpose of this conference was to bring together researchers from universities, industrial laboratories, and other research institutions with common interests in architectures and hardware technology, software, and applications for supercomputers. Authors from 12 countries submitted 107 papers, from which 52 were accepted and presented at the conference. In addition, 15 distinguished researchers presented invited papers. The papers from these presentations make up the current proceedings volume. Based on the quality of the papers presented and the response and excitement of the participants, the Program Committee has decided to hold annual meetings on the subject of supercomputing.

Recent technology involves large-scale physical or engineering systems consisting of thousands of interconnected elementary units. This monograph illustrates how engineering problems can be solved using the recent results of combinatorial mathematics through appropriate mathematical modeling. The structural solvability of a system of linear or nonlinear equations as well as the structural controllability of a linear time-invariant dynamical system are treated by means of graphs and matroids. Special emphasis is laid on the importance of relevant physical observations to successful mathematical modelings. The reader will become acquainted with the concepts of matroid theory and its corresponding matroid theoretical approach. This book is of interest to graduate students and researchers.

This volume contains the proceedings of the 14th International Colloquium on Automata Languages and Programming, organized by the European Association for Theoretical Computer Science (EATCS) and held in Karlsruhe, July 13-17, 1987. The papers report on original research in theoretical computer science and cover topics such as algorithms and data structures, automata and formal languages, computability and complexity theory, semantics of programming languages, program specification, transformation and verification, theory of data bases, logic programming, theory of logical design and layout, parallel and distributed computation, theory of concurrency, symbolic and algebraic computation, term rewriting systems, cryptography, and theory of robotics. The authors are young scientists and leading experts in these areas.

"This book is a comprehensive text for the design of safety critical, hard real-time embedded systems. It offers a splendid example for the balanced, integrated treatment of systems and software engineering, helping readers tackle the hardest problems of advanced real-time system design, such as determinism, compositionality, timing and fault management. This book is an essential reading for advanced undergraduates and graduate students in a wide range of disciplines impacted by embedded computing and software. Its conceptual clarity, the style of explanations and the examples make the abstract concepts accessible for a wide audience." Janos Sztipanovits, Director E. Bronson Ingram Distinguished Professor of Engineering Institute for Software Integrated Systems Vanderbilt University Real-Time Systems focuses on hard real-time systems, which are computing systems that must meet their temporal specification in all anticipated load and fault scenarios. The book stresses the system aspects of distributed real-time applications, treating the issues of real-time, distribution and fault-tolerance from an integral point of view. A unique cross-fertilization of ideas and concepts between the academic and industrial worlds has led to the inclusion of many insightful examples from industry to explain the fundamental scientific concepts in a real-world setting. Compared to the Second Edition, new developments in communication standards for time-sensitive networks, such as TSN and Time-Triggered Ethernet are addressed. Furthermore, this edition includes a new chapter on real-time aspects in cloud and fog computing. The book is written as a standard textbook for a high-level undergraduate or graduate course on real-time embedded systems or cyber-physical systems. Its practical approach to solving real-time problems, along with numerous summary exercises, makes it an excellent choice for researchers and practitioners alike.

In verteilten Systemen sind zwischen den Stellen Nachrichten auszutauschen. Die Zeiten, welche fur diese Nachrichtentransporte benotigt werden, konnen dazu fuhren, dass Nachrich- ten bereits veraltet sind, wenn sie interpretiert werden; dies kann den Wert der gewonnen Informationen mindern. Diese allgemeine AufgabensteIlung haben wir fur die Berechnung und Bewertung von Permu- tationsstrategien formuliert und abgehandelt. Fur diesen Anwendungsbereich konnten die Charakteristika der AufgabensteIlung leicht formuliert werden, weil fur die Anderungsge- schwindigkeiten der betrachteten Nachrichten und fur die Bewertung der gewonnenen Infor- mationen naheliegende Funktionen benutzt werden konnen. Die angegebene Problemstellung der Wertminderung von Informationen durch Interpretation veralteter Nachrichten ist fur viele praktische Anwendungen von Interesse. Man denke etwa an eine Bank, welche die Konten ihrer Kunden verteilt fuhrt. Die Schwierigkeiten prakti- scher Anwendungen liegen in der exakten Formulierung der AufgabensteIlung; sie erfordert Kenntnis der Anderungsgeschwindigkeit der betrachteten Nachrichten und anerkannte Bewer- tungsfunktionen fur Informationen. Die Durchfuhrung entsprechender Analysen sollte, wenn diese Voraussetzungen erfullt sind, keine besonderen Schwierigkeiten bereiten. Die angegebene Problemstellung ist auch im Zusammenhang mit der Entwicklung von ver- teilten Systemen von Interesse. Fur die Kommunikation in verteilten Systemen werden zahl- reiche Verfahren diskutiert; sie unterscheiden sich insbesondere bzgl. der zeitlichen Kopp- lung der Kommunikationspartner. Die hier angegebene Problemstellung kann als Grundlage fur die Auswahl angemessener Kommunikationsverfahren herangezogen werden. Dies weist erneut auf die Notwendigkeit hin, quantitative Analysen zur Begrundung von Entwicklungs- Entscheidungen heranzuziehen. LITERATUR Andrews, G.R., Schneider, F.B.