6th Refinement Workshop


Book Description

The Sixth Refinement Workshop took place at City University in London from 5th to 7th January 1994. The present volume includes all of the papers which were submitted and accepted for presentation, together with two papers by invited speakers. The workshops in the series have generally occurred at one year intervals but in this last case a two year period had elapsed. These workshops have established themselves as an important event in the calendar for all those who are interested in progress in the underlying theory of refinement and in the take-up by industry of the methods supported by that theory. One of the proposed themes of the sixth workshop was the reporting of successful adoption in industry of rigorous software development methods. The programme committee was perhaps slightly disappointed by the response from industry to the call in this respect. However, the recent period could be characterised as one of consolidation, when those companies which have made the decision that formal development methods are important to their business have been adopting them where appropriate and finding them to be worthwhile. On the other hand,. the difficult economic climate which exists in most parts of the developed world is perhaps not the context within which companies still dubious about the benefits are goil'\g to opt for making major changes in their working practices.




4th Refinement Workshop


Book Description

This volume contains the proceedings ofthe 4th Refinement Workshop which was organised by the British Computer Society specialist group in Formal Aspects of Computing Science and held in Wolfson College, Cambridge, on 9-11 January, 1991. The term refinement embraces the theory and practice of using formal methods for specifying and implementing hardware and software. Most of the achievements to date in the field have been in developing the theoretical framework for mathematical approaches to programming, and on the practical side in formally specifying software, while more recently we have seen the development of practical approaches to deriving programs from their speCifications. The workshop gives a fair picture of the state of the art: it presents new theories for reasoning about software and hardware and case studies in applying known theory to interesting small-and medium-scale problems. We hope the book will be Of interest both to researchers in formal methods, and to software engineers in industry who want to keep abreast of possible applications of formal methods in industry. The programme consisted both of invited talks and refereed papers. The invited speakers were Ib S0rensen, Jean-Raymond Abrial, Donald MacKenzie, Ralph Back, Robert Milne, Mike Read, Mike Gordon, and Robert Worden who gave the introductory talk. This is the first refinement workshop that solicited papers for refereeing, and despite a rather late call for papers the response was excellent.




5th Refinement Workshop


Book Description

Refinement is the term used to describe systematic and formal methods of specifying hard- and software and transforming the specifications into designs and implementations. The value of formal methods in producing reliable hard- and software is widely appreciated by academics and workers in industry, despite the fact that certain research areas, such as the application to industrial-scale problems, are still in their infancy. This volume contains the papers presented at the 5th Refinement Workshop held in London, 8-10 January 1992. Its theme was the theory and practice of software specifications, which is the transformation of formal software specifications into more correct specifications, designs and codes. This has been an important area of research for the last 5 years and the workshop addressed specific issues and problems related to it. Among the topics discussed in this volume are: the role of refinement in software development, parallel designs and implementations, methods and tools for verification of critical properties, refinement and confidentiality, concurrent processes as objects, the compliance of Ada programs with Z specifications and a tactic driven refinement tool. This is the latest refinement workshop proceedings to be published in the Workshops in Computing series (the 3rd and 4th workshops having appeared in 1990 and 1991 respectively). It will be of interest to academic and industrial researchers, postgraduate students and research-oriented developers in the computer industry.




Rules in Database Systems


Book Description

This book is the proceedings of a workshop held at Heriot-Watt University in Edinburgh in August 1993. The central theme of the workshop was rules in database systems, and the papers presented covered a range of different aspects of database rule systems. These aspects are reflected in the sessions of the workshop, which are the same as the sections in this proceedings: Active Databases Architectures Incorporating Temporal Rules Rules and Transactions Analysis and Debugging of Active Rules Integrating Graphs/Objects with Deduction Integrating Deductive and Active Rules Integrity Constraints Deductive Databases The incorporation of rules into database systems is an important area of research, as it is a major component in the integration of behavioural information with the structural data with which commercial databases have traditionally been associated. This integration of the behavioural aspects of an application with the data to which it applies in database systems leads to more straightforward application development and more efficient processing of data. Many novel applications seem to need database systems in which structural and behavioural information are fully integrated. Rules are only one means of expressing behavioural information, but it is clear that different types of rule can be used to capture directly different properties of an application which are cumbersome to support using conventional database architectures. In recent years there has been a surge of research activity focusing upon active database systems, and this volume opens with a collection of papers devoted specifically to this topic.




Designing Correct Circuits


Book Description

These proceedings contain the papers presented at a workshop on Designing Correct Circuits, jointly organised by the Universities of Oxford and Glasgow, and held in Oxford on 26-28 September 1990. There is a growing interest in the application to hardware design of the techniques of software engineering. As the complexity of hardware systems grows, and as the cost both in money and time of making design errors becomes more apparent, so there is an eagerness to build on the success of mathematical techniques in program develop ment. The harsher constraints on hardware designers mean both that there is a greater need for good abstractions and rigorous assurances of the trustworthyness of designs, and also that there is greater reason to expect that these benefits can be realised. The papers presented at this workshop consider the application of mathematics to hardware design at several different levels of abstraction. At the lowest level of this spectrum, Zhou and Hoare show how to describe and reason about synchronous switching circuits using UNilY, a formalism that was developed for reasoning about parallel programs. Aagaard and Leeser use standard mathematical tech niques to prove correct their implementation of an algorithm for Boolean simplification. The circuits generated by their formal synthesis system are thus correct by construction. Thuau and Pilaud show how the declarative language LUSTRE, which was designed for program ming real-time systems, can be used to specify synchronous circuits.




Z User Workshop, Oxford 1990


Book Description




Neural Computation and Psychology


Book Description

The papers that appear in this volume are refereed versions of presenta tions made at the third Neural Computation and Psychology Workshop, held at Stirling University, Scotland, from 31 August to 2 September 1994. The aim of this series of conferences has been to explore the interface between Neural Computing and Psychology: this has been a fruitful area for many researchers for a number of reasons. The development ofNeural Computation has supplied tools to researchers in Cognitive Neuroscience, allowing them to look at possible mechanisms for implementing theories which would otherwise remain 'black box' techniques. These theories may be high-level theories, concerned with interaction between a number of brain areas, or low-level, describing the way in which smaller local groups of neurons behave. Neural Computation techniques have allowed computer scientists to implement systems which are based on how real brains appear to function, providing effective pattern recognition systems. We can thus mount a two-pronged attack on perception. The papers here come from both the Cognitive Psychology viewpoint and from the Computer Science viewpoint: it is a mark of the growing maturity of the interface between the two subjects that they can under stand each other's papers, and the level of discussion at the workshop itself showed how important each camp considers the other to be. The papers here are divided into four sections, reflecting the primary areas of the material.




Asynchronous Digital Circuit Design


Book Description

As the costs of power and timing become increasingly difficult to manage in traditional synchronous systems, designers are being forced to look at asynchronous alternatives. Based on reworked and expanded papers from the VII Banff Higher Order Workshop, this volume examines asynchronous methods which have been used in large circuit design, ranging from initial formal specification to more standard finite state machine based control models. Written by leading practitioners in the area, the papers cover many aspects of current practice including practical design, silicon compilation, and applications of formal specification. It also includes a state-of-the-art survey of asynchronous hardware design. The resulting volume will be invaluable to anyone interested in designing correct asynchronous circuits which exhibit high performance or low power operation.




Semantics of Specification Languages (SoSL)


Book Description

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.




Logic Program Synthesis and Transformation


Book Description

Logic program synthesis and transformation are topics of central importance to the software industry. The demand for software can not be met by the current supply, in terms of volume, complexity, or reliability. The most promising solution seems to be the increased automation of software production: programmer productivity would improve, and correctness could be ensured by the application of mathematical methods. Because of their mathematical foundations, logic programs lend themselves particularly well to machine-assisted development techniques, and therefore to automation. This volume contains the proceedings of the second International Workshop on Logic Program Synthesis and Transformation (LOPSTR 92), held at the University of Manchester, 2-3 July 1992. The LOPSTR workshops are the only international meetings devoted to these two important areas. A variety of new techniques were described at the workshop, all of which promise to revolutionize the software industry once they become standard practise. These include techniques for the transformation of an inefficient program into an equivalent, efficient one, and the synthesis of a program from a formal specification of its required behaviour. Among the topics covered in this volume are: optimal transformation of logic programs; logic program synthesis via proof planning; deductive synthesis of programs for query answering; efficient compilation of lazy narrowing into Prolog; synthesis of narrowing programs; Logimix: a self-applicable partial evaluator for Prolog; proof nets; automatic termination analysis. Logic Program Synthesis and Transformation describes the latest advances in machine-assisted development of logic programs. It will provide essential reading for researchers and postgraduate students concerned with these two important areas.