The state-based CCS semantics for concurrent Z specification

Presents a formal method which combines the Z notation and value-passing CCS (Calculus of Communicating Systems) for specifying concurrent systems. In order to provide a sound theoretical basis for the method, the state-based semantics for value-passing CCS is given. The main characteristic of the semantics is its ability in describing the evolution of processes and transitions of states simultaneously. We also present a Hennessy-Milner logic based on that semantics, which enables us to express properties such as liveness and safety ascribed both to states and to actions.