Quantitative Verification of System Safety in Event-B
نویسندگان
چکیده
Certification of safety-critical systems requires formal verification of system properties and behaviour as well as quantitative demonstration of safety. Usually, formal modelling frameworks do not include quantitative assessment of safety. This has a negative impact on productivity and predictability of system development. In this paper we present an approach to integrating quantitative safety analysis into formal system modelling and verification in Event-B. The proposed approach is based on an extension of Event-B, which allows us to perform quantitative assessment of safety within proofbased verification of system behaviour. This enables development of systems that are not only correct but also safe by construction. The approach is demonstrated by a case study – an automatic railway crossing system.
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