VDM '91. Formal Software Development Methods. 4th International Symposium of VDM Europe, Noordwijkerhout, The Netherlands, October 21-25, 1991. Proceedings


Book Description

The proceedings of the fourth Vienna Development Method Symposium, VDM'91, are published here in two volumes. Previous VDM symposia were held in 1987 (LNCS 252), 1988 (LNCS 328), and 1990 (LNCS 428). The VDM symposia have been organized by VDM Europe, formed in 1985 as an advisory board sponsored by the Commission of the European Communities. The VDM Europe working group consisted of researchers, software engineers, and programmers, allinterested in promoting the industrial usage of formal methods for software development. The fourth VDM symposium presented not only VDM but also a large number of other methods for formal software development. Volume 1 contains conference contributions. It has four parts: contributions of invited speakers, papers, project reports, and tools demonstration abstracts. The emphasis is on methods and calculi for development, verification and verification tools support, experiences from doing developments, and the associated theoretical problems. Volume 2 contains four introductory tutorials (on LARCH, Refinement Calculus, VDM, and RAISE) and four advanced tutorials (on ABEL, PROSPECTRA, The B Method, and The Stack). They present a comprehensive account of the state of theart.




Specification of Software Systems


Book Description

This book provides an introduction to program specification, illustrating the advantages it confers upon the software development process. Covering all three major specification languages (Larch, VDM, and Z), the book discusses specification in general, the abstraction process, the mathematical tools required, and the main formal methods.




Distributed Computer Control Systems 1991


Book Description

Distributed computer control is at the intersection between control engineering and computer science. Containing 22 papers, this book provides an up-to-date reference source of important issues in the design and implementation of distributed real-time computer systems.




Z User Workshop, York 1991


Book Description

In ordinary mathematics, an equation can be written down which is syntactically correct, but for which no solution exists. For example, consider the equation x = x + 1 defined over the real numbers; there is no value of x which satisfies it. Similarly it is possible to specify objects using the formal specification language Z [3,4], which can not possibly exist. Such specifications are called inconsistent and can arise in a number of ways. Example 1 The following Z specification of a functionf, from integers to integers "f x : ~ 1 x ~ O· fx = x + 1 (i) "f x : ~ 1 x ~ O· fx = x + 2 (ii) is inconsistent, because axiom (i) gives f 0 = 1, while axiom (ii) gives f 0 = 2. This contradicts the fact that f was declared as a function, that is, f must have a unique result when applied to an argument. Hence no suchfexists. Furthermore, iff 0 = 1 andfO = 2 then 1 = 2 can be deduced! From 1 = 2 anything can be deduced, thus showing the danger of an inconsistent specification. Note that all examples and proofs start with the word Example or Proof and end with the symbol.1.




Z User Workshop, London 1992


Book Description

The Z notation has been developed at the Programming Research Group at the Oxford University Computing Laboratory and elsewhere for over a decade. It is now used by industry as part of the software (and hardware) development process in both Europe and the USA. It is currently undergoing BSI standardisation in the UK, and has been proposed for ISO standardisation internationally. In recent years researchers have begun to focus increasingly on the development of techniques and tools to encourage the wider application of Z and other formal methods and notations. This volume contains papers from the Seventh Annual Z User Meeting, held in London in December 1992. In contrast to previous years the meeting concentrated specifically on industrial applications of Z, and a high proportion of the participants came from an industrial background. The theme is well represented by the four invited papers. Three of these discuss ways in which formal methods are being introduced, and the fourth presents an international survey of industrial applications. It also provides a reminder of the improvements which are needed to make these methods an accepted part of software development. In addition the volume contains several submitted papers on the industrial use of Z, two of which discuss the key area of safety-critical applications. There are also a number of papers related to the recently-completed ZIP project. The papers cover all the main areas of the project including methods, tools, and the development of a Z Standard, the first publicly-available version of which was made available at the meeting. Finally the volume contains a select Z bibliography, and section on how to access information on Z through comp.specification.z, the international, computer-based USENET newsgroup. Z User Workshop, London 1992 provides an important overview of current research into industrial applications of Z, and will provide invaluable reading for researchers, postgraduate students and also potential industrial users of Z.




Program Development by Specification and Transformation


Book Description

This volume gives a coherent presentation of the outcome of the project PROSPECTRA (PROgram development by SPECification and TRAnsformation) that aims to provide a rigorous methodology for developing correct software and a comprehensive support system. The results are substantial: a theoretically well-founded methodology covering the whole development cycle, a very high-level specification and transformation language family allowing meta-program development and formalization of the development process itself, and a prototype development system supporting structure editing, incremental static-semantic checking, interactive context-sensitivetransformation and verification, development of transformation (meta-) programs, version management, and so on, with an initial libraryof specifications and a sizeable collection of implemented transformations. The intended audience for this documentation is the academic community working in this and related areas and those members of the industrial community interested in the use of formal methods.




ZUM '98: The Z Formal Specification Notation


Book Description

1 In a number of recent presentations – most notably at FME’96 –oneofthe foremost scientists in the ?eld of formal methods, C.A.R. Hoare,has highlighted the fact that formal methods are not the only technique for producing reliable software. This seems to have caused some controversy,not least amongst formal methods practitioners. How can one of the founding fathers of formal methods seemingly denounce the ?eld of research after over a quarter of a century of support? This is a question that has been posed recently by some formal methods skeptics. However, Prof. Hoare has not abandoned formal methods. He is reiterating, 2 albeitmoreradically,his1987view thatmorethanonetoolandnotationwillbe requiredinthepractical,industrialdevelopmentoflarge-scalecomplexcomputer systems; and not all of these tools and notations will be, or even need be, formal in nature. Formalmethods arenotasolution,butratheroneofaselectionoftechniques that have proven to be useful in the development of reliable complex systems, and to result in hardware and software systems that can be produced on-time and within a budget, while satisfying the stated requirements. After almostthree decades,the time has come to view formalmethods in the context of overall industrial-scale system development, and their relationship to othertechniquesandmethods.Weshouldnolongerconsidertheissueofwhether we are “pro-formal” or “anti-formal”, but rather the degree of formality (if any) that we need to support in system development. This is a goal of ZUM’98, the 11th International Conference of Z Users, held for the ?rst time within continental Europe in the city of Berlin, Germany.




New Results and New Trends in Computer Science


Book Description

This volume contains selected papers from the symposium "New Results and NewTrends in Computer Science" held in Graz, Austria, June 20-21, 1991. The symposium was organized to give a wide-ranging overview of new work in the field on the occasion of the fiftieth birthday of the editor of the volume. Topics covered include: information on neural nets, ideas on a new paradigm for informatics, hypermedia systems and applications, axioms for concurrent processes, techniques for image generation and compression, the role of data visualization, object-oriented programming andgraphics, algorithms for layout compaction, new methods in database systems, the future of data networks, object-oriented artificial intelligence, problems in data structures and sorting, aspects of user interfaces, a theory of structures, applications of cryptography, evaluation of Ada, results in algorithmic geometry, remarks on the history of computers, and a novel interpretation of machine learning. In total, the 26 high-level contributions authored by prominent experts from all over the world give an up-to-date survey of almost all subfields of computer science. The book is written in a style which is easy to follow, and it is of interest for any computer scientist, be it in research, teaching or practice.




From Object-Orientation to Formal Methods


Book Description

This book is dedicated to the memory of Ole-Johan Dahl who passed away in June 2002 at the age of 70, shortly after he had received, together with his colleague Kristen Nygaard, the ACM Alan M. Turing Award: "For ideas fundamental to the emergence of object-oriented programming, through their design of the programming languages Simula I and Simula 67." This Festschrift opens with a short biography and a bibliography recollecting Ole-Johan Dahl's life and work, as well as a paper he wrote entitled: "The Birth of Object-Orientation: the Simula Languages." The main part of the book consists of 14 scientific articles written by leading scientists who worked with Ole-Johan Dahl as students or colleagues. In accordance with the scope of Ole-Johan Dahl's work and the book's title, the articles are centered around object-orientation and formal methods.




SOFSEM'99: Theory and Practice of Informatics


Book Description

This year the SOFSEM conference is coming back to Milovy in Moravia to th be held for the 26 time. Although born as a local Czechoslovak event 25 years ago SOFSEM did not miss the opportunity oe red in 1989 by the newly found freedom in our part of Europe and has evolved into a full-?edged international conference. For all the changes, however, it has kept its generalist and mul- disciplinarycharacter.Thetracksofinvitedtalks,rangingfromTrendsinTheory to Software and Information Engineering, attest to this. Apart from the topics mentioned above, SOFSEM’99 oer s invited talks exploring core technologies, talks tracing the path from data to knowledge, and those describing a wide variety of applications. TherichcollectionofinvitedtalkspresentsonetraditionalfacetofSOFSEM: that of a winter school, in which IT researchers and professionals get an opp- tunity to see more of the large pasture of today’s computing than just their favourite grazing corner. To facilitate this purpose the prominent researchers delivering invited talks usually start with a broad overview of the state of the art in a wider area and then gradually focus on their particular subject.