Critical infrastructures provide services upon which society depends heavily; these applications are themselves dependent on distributed information systems for all aspects of their operation and so survivability of the information systems is an important issue. Fault tolerance is a key mechanism by which survivability can be achieved in these information systems. We outline a specification-bas...

UML is a standard modelling language that is able to specify a wide range of object-oriented concepts. Among them, we have collaborations, that serve to realise use cases, a powerful abstraction concept. The behaviour part of a collaboration is rendered using collaboration diagrams. However, the lack of formalisation compromises the precision of the specification. By using formal description te...

A component of the software that controls traffic lights usually is devoted only to monitoring the state of the traffic junction, to assess its safety, and to take appropriate action if an unsafe state occurs. That component, the safety controller, should be reusable for many traffic junctions. We present the specification of such a safety controller in the specification language SZ, which comb...

The work presented in this article is based upon a methodological approach for building Multi-Agent Systems specifications. The basic idea is to define such systems as a set of entities playing roles which have interactions between them. We present a mechanism for dynamic role-playing specification within a formal framework. The framework use a formalism which can express Multi-Agent Systems as...

Checking for properties of Web ontologies is important for the development of reliable Semantic Web systems. Software specification and verification tools can be used to complement the Knowledge Representation tools in reasoning about Semantic Web. The key to this approach is to develop sound transformation techniques from Web ontology to software specifications so that the associated verificat...

Object oriented constraint programs (OOCPs) emerge as a leading evolution of constraint programming and artificial intelligence, first applied to a range of industrial applications called configuration problems. The rich variety of technical approaches to solving configuration problems (CLP(FD), CC(FD), DCSP, Terminological systems, constraint programs with set variables, . . . ) is a source of...

This appendix provides some details on how to access information on Z, particularly electronically. It has been generated from a message that is updated and sent out monthly on international computer networks. This on-line information is available on-line on the following World Wide Web (WWW) hypertext page where it is split into convenient sections and updated each month: http://www.cis.ohio-s...

Railway interlocking system is a distributed, safety, monetary and environmentally critical system and its failure may cause the loss of human life, severe injuries, loss of money and environmental damages. The complexity of this system requires formal modeling and step by step refinement for its construction and development. The formal specification-based languages, such as V DM , Z-notation a...

Graphical notations such as UML are very popular thanks to their simplicity and their intuitive aspect. Nevertheless their lack of precise semantics limits the possibility of the specification validation. So we propose here to translate some of the UML models into Z and Lustre formal specifications in order to use a theorem prover and a test generator to validate the models. This approach is pr...

This paper gives details of a small example to illustrate the use of Formal Methods of system and software development, including modelling, specification, validation and design verification. The example concerns part of a simple hypothetical Air Traffic Control system. Z notation and the Cogito methodology are used. A Suggested Reading List is included for readers wishing to know more about th...