Operational specification for FCA using Z

We present an outline of a process by which operational software requirements specifications can be written for Formal Concept Analysis (FCA). The Z notation is used to specify the FCA model and the formal operations on it. We posit a novel approach whereby key features of Z and FCA can be integrated and put to work in contemporary software development, thus promoting operational specification as a useful application of conceptual structures.</p

A Historical Perspective on Runtime Assertion Checking in Software Development

This report presents initial results in the area of software testing and analysis produced as part of the Software Engineering Impact Project. The report describes the historical development of runtime assertion checking, including a description of the origins of and significant features associated with assertion checking mechanisms, and initial findings about current industrial use. A future report will provide a more comprehensive assessment of development practice, for which we invite readers of this report to contribute information

Z Unification Tools in Generic Formaliser

We describe some prototype tools for performing unification (i.e. deriving the least common refinement) of simple Z specifications. The techniques used are those described in http://alethea.ukc.ac.uk/Dept/Computing/Research/NDS/consistency/cccfpsiZ.html on viewpoint specification in Z; the tools have been implemented in Generic http://public.logica.com/formaliser (a product of Logica UK Limited). UKC Computing Laboratory technical report 10-97. The prototype tools themselves (in the form of Generic Formaliser grammars) will be made available later

Z-style notation for Probabilities

A notation for probabilities is proposed that differs from the traditional, conventional notation by making explicit the domains and bound variables involved. The notation borrows from the Z notation, and lends itself well to calculational manipulations, with a smooth transition back and forth to set and predicate notation

Unification and multiple views of data in Z

This paper discusses the unification of Z specifications, in particular specifications that maintain different representations of what is intended to be the same datatype. Essentially this amounts to integrating previously published techniques for combining multiple viewpoints and for combining multiple views. It is shown how the technique proposed in this paper indeed produces unifications, and that it generalises both previous techniques

Determining the quality of mathematical software using reference data sets

This paper describes a methodology for evaluating the numerical accuracy of software that performs mathematical calculations. The authors explain how this methodology extends the concept of metrological traceability, which is fundamental to measurement, to include software quality. Overviews of two European Union-funded projects are also presented. The first project developed an infrastructure to allow software to be verified by testing, via the internet, using reference data sets. The primary focus of the project was software used within systems that make physical measurements. The second project, currently underway, explores using this infrastructure to verify mathematical software used within general scientific and engineering disciplines. Publications on using reference data sets for the verification of mathematical software are usually intended for a readership specialising in measurement science or mathematics. This paper is aimed at a more general readership, in particular software quality specialists and computer scientists. Further engagement with experts in these disciplines will be helpful to the continued development of this application of software quality

Formalization and Validation of Safety-Critical Requirements

The validation of requirements is a fundamental step in the development process of safety-critical systems. In safety critical applications such as aerospace, avionics and railways, the use of formal methods is of paramount importance both for requirements and for design validation. Nevertheless, while for the verification of the design, many formal techniques have been conceived and applied, the research on formal methods for requirements validation is not yet mature. The main obstacles are that, on the one hand, the correctness of requirements is not formally defined; on the other hand that the formalization and the validation of the requirements usually demands a strong involvement of domain experts. We report on a methodology and a series of techniques that we developed for the formalization and validation of high-level requirements for safety-critical applications. The main ingredients are a very expressive formal language and automatic satisfiability procedures. The language combines first-order, temporal, and hybrid logic. The satisfiability procedures are based on model checking and satisfiability modulo theory. We applied this technology within an industrial project to the validation of railways requirements