The proper treatment and choice of the basic data structures is an important and complex part in the process of program construction. Algebraic methods provide techniques for data abstraction and the structured specification, validation and analysis of data structures. This volume originates from a workshop organized within ESPRIT Project 432 METEOR, An Integrated Formal Approach to Industrial Software Development, held in Mierlo, The Netherlands, September 1989. The volume includes five invited contributions based on workshop talks given by A. Finkelstein, P. Klint, C.A. Middelburg, E.-R. Olderog, and H.A. Partsch. Ten further papers by members of the METEOR team are based on talks given at the workshop. The workshop was a successor to an earlier one held in Passau, Germany, June 1987, the proceedings of which were published as Lecture Notes in Computer Science, Vol. 394.

This book presents the leading edge in several related fields, specifically object orientated programming, open distributed systems and formal methods for object oriented systems. With increased support within industry regarding these areas, this book captures the most up-to-date information on the subject. Many topics are discussed, including the following important areas: object oriented design and programming; formal specification of distributed systems; open distributed platforms; types, interfaces and behaviour; formalisation of object oriented methods.

Increasingly, formal specification is being used by database researchers to describe and understand the systems they are designing and implementing. Similarly, those working on formal specification techniques have recognised that the database field provides a rich context for developing their ideas. However, as experts in one field often have a relatively limited knowledge of the other, there is a growing need for discussion about the relationship between these two fields and how they can be usefully combined. This volume contains the 16 papers which were presented at the International Workshop on Specification on Database Systems, held in Glasgow, 3-5 July 1991. The purpose of the workshop was to bring together these fields and to examine, through a series of invited talks, presentations and working groups, the role that formal specification can play in developing database systems. The papers describe current research into topics such as the formal specification of data models, query languages and transaction handling and the use of formal specification techniques to understand problems which arise in database systems. The working groups, which are summarised at the end of the volume, covered a variety of issues including the role of graphical notations in database specification, the use of specification techniques in enabling "open" or extensible database systems and the education of the database community in specification techniques. This volume will be invaluable to the increasing number of researchers who are using both database systems and formal specification techniques in their work, and who wish to gain a more detailed knowledge of these two fields and the issues which affect them.

SoSL was the first International Workshop on Semantics of Specification Languages, held from 25-27 October 1993 in Utrecht, the Netherlands. The workshop was organized by the Department of Philosophy of Utrecht University with financial support from the Nationale Faciliteit Informatica of the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO), and under the auspices of the British Computer Society'S specialist group in Formal Aspects of Computing Science (BCS FACS). The concern of the workshop was the semantics of specification languages, and the issues closely related to this area, such as type checking and the justification of proof rules and proof obligations. Its aim was the exchange of problems and ideas in this field of formal methods, and the identification of common programs of work for further investigation. The program of SoSL consisted of 3 invited lectures presenting the developments of the semantics of 3 major specification languages. Furthermore, there were 16 presentations of submitted papers. This volume provides a direct account of the workshop. It contains 3 papers that match the invited lectures and the 16 selected papers. The editors want to thank all those who have contributed to the workshop; the Program Committee and the referees for selecting the contributed papers, the invited speakers for their interesting talks, the Organizing Committee for all their efforts, and of course the participants. We have the feeling that the workshop was worthwhile and should be repeated.

This systematic algebraic approach offers a careful formulation of the problems' physical motivations as well as self-contained descriptions of the mathematical methods for arriving at solutions. 1972 edition.

Formality is becoming accepted as essential in the development of complex systems such as multi-layer communications protocols and distributed systems. Formality is mandatory for mathematical verification, a procedure being imposed on safety-critical system development. Standard documents are also becoming increasingly formalised in order to capture notions precisely and unambiguously. This FORTE '91 proceedings volume has focussed on the standardised languages SDL, Estelle and LOTOS while, as with earlier conferences, remaining open to other notations and techniques, thus encouraging the continuous evolution of formal techniques. This useful volume contains 29 submitted papers, three invited papers, four industry reports, and four tool reports organised to correspond with the conference sessions.