On syntactic action refinement and logic

Action refinement is a useful methodology for the development of concurrent processes in a stepwise manner. We are here interested in establishing a connection between syntactic action refinement and logic. In the syntactic approach to action refinement, reduction functions are used to remove the refinement operators from process-algebraic expressions thereby providing semantics for them. We incorporate a syntactic action refinement operator to the Hennessy-Milner-Logic and define a logical reduction function for this extended logic. This provides a possibility to refine a process expression and a formula simultaneously on the syntactic level, while preserving their satisfaction relation. It turns out that the assertion P ≠ φ ⇔ P[a ⇔ Q] ≠ φ[a ⇔ Q] where .(a ⇔ Q] denotes the refinement operator both, on process terms and formulas holds in the considered framework under weak and reasonable restrictions

Verification in the Hierarchical Development of Reactive Systems

In many approaches to the verification of reactive systems, operational semantics are used to model systems whereas specifications are expressed in temporal logics. Most approaches however fail to handle changes of the specification but assume, that the initial specification is indeed the intended one. Changing the specification thus necessitates to find an accordingly adapted system and to carry out the verification from scratch. During a systems life cycle however, changes of the requirements and resources necessitate repeated adaptations of specifications. We here propose a method that supports syntactic action refinement (in the process algebra TCSP and the Modal Mu-Calculus) and allows to automatically obtain (a priori) correct reactive systems by hierarchically adding details to the according specifications