Concurrent systems abound in human experience but their fully adequate conceptualization as yet eludes our most able thinkers. The COSY (ConcurrentSystem) notation and theory was developed in the last decade as one of a number of mathematical approaches for conceptualizing and analyzing concurrent and reactive systems. The COSY approach extends theconventional notions of grammar and automaton from formal language and automata theory to collections of "synchronized" grammars and automata, permitting system specification and analysis of "true" concurrency without reduction to non-determinism. COSY theory is developed to a great level of detail and constitutes the first uniform and self-contained presentationof all results about COSY published in the past, as well as including many new results. COSY theory is used to analyze a sufficient number of typical problems involving concurrency, synchronization and scheduling, to allow the reader to apply the techniques presented tosimilar problems. The COSY model is also related to many alternative models of concurrency, particularly Petri Nets, Communicating Sequential Processes and the Calculus of Communicating Systems.

This book presents the refereed proceedings of the 6th International Symposium on Algorithms and Computation, ISAAC '95, held in Cairns, Australia, in December 1995. The 45 revised full papers presented together with the abstracts of three invited talks were selected from a total of 130 submissions. The papers address many current aspects of research and advanced applications of algorithms and computations; among the topics covered are graph theory and graph algorithms, computational geometry, computational logics, searching and sorting, approximation and optimization, algebraic manipulation, and coding.

This volume constitutes the proceedings of the Fifth International Conference on Concurrency Theory, CONCUR '94, held at Uppsala, Sweden in August 1994. In total, 29 refereed research papers selected from 108 submissions for the conference are presented together with full papers or abstracts of the 5 invited talks by prominent speakers. The book contains recent results on all relevant aspects of concurrency research and thus competently documents the progress of the field since the predecessor conference CONCUR '93, the proceedings of which are published as LNCS 715.

This volume contains papers presented at the BCS-FACS Workshop on Specification and Verification of Concurrent Systems held on 6-8 July 1988, at the University of Stirling, Scotland. Specification and verification techniques are playing an increasingly important role in the design and production of practical concurrent systems. The wider application of these techniques serves to identify difficult problems that require new approaches to their solution and further developments in specification and verification. The Workshop aimed to capture this interplay by providing a forum for the exchange of the experience of academic and industrial experts in the field. Presentations included: surveys, original research, practical experi ence with methods, tools and environments in the following or related areas: Object-oriented, process, data and logic based models and specifi cation methods for concurrent systems Verification of concurrent systems Tools and environments for the analysis of concurrent systems Applications of specification languages to practical concurrent system design and development. We should like to thank the invited speakers and all the authors of the papers whose work contributed to making the Workshop such a success. We were particularly pleased with the international response to our call for papers. Invited Speakers Pierre America Philips Research Laboratories University of Warwick Professor M. Joseph David Freestone British Telecom Organising Committee Charles Rattray Dr Muffy Thomas Dr Simon Jones Dr John Cooke Professor Ken Turner Derek Coleman Maurice Naftalin Dr Peter Scharbach vi Preface We would like to aeknowledge the finaneial eontribution made by SD-Sysems Designers pie, Camberley, Surrey.