UCL Discovery

Abstract

We present a logic and logic programming based approach for analysing event-based requirements specifications given in terms of a system’s reaction to events and safety properties. The approach uses a variant of Kowalski and Sergot’s Event Calculus to represent such specifications declaratively and an abductive reasoning mechanism for analysing safety properties. Given a system description and a safety property, the abductive mechanism is able to identify a complete set of counterexamples (if any exist) of the property in terms of symbolic “current” states and associated event-based transitions. A case study of an automobile cruise control system specified in the SCR framework is used to illustrate our approach. The technique described is implemented using existing tools for abductive logic programming.