Abstract. Failures are unavoidable in many circumstances. For example, an agent may fail at some point to perform a task in a dynamic environment. Robust systems typically have mechanisms to handle such failures. Temporal logic is a widely used representation language for reasoning about the behaviour of systems, although dealing with failures is not part of the language. In this paper, it is investigated how interval temporal logic can be extended with an operator describing failure. This logic has a close relationship to exception handling mechanisms in programming languages, which provides an elegant mechanism for modelling and handling failures. The approach is motivated from the context of specification of systems that have to operate in highly dynamic environments. A case study of the formal modelling and verification of the treatment of diabetes mellitus type 2 illustrates the practical usefulness of the approach.
Arjen Hommersom, Peter J. F. Lucas