Refinement of Actions in a Real-Time Process Algebra with a True Concurrency Model

Abstract

In this paper, we develop techniques of action refinement in a real-time process algebra that allows urgent interactions to model timeout. Semantic counterpart is carried out in a real-time non-interleaving causality based setting, timed bundle event structures. We show that our refinement notions have the following nice properties: the observable behaviour of the refined system can be inferred compositionally from the observable behaviour of the original system and from the observable behaviour of the processes substituted for the actions; the timed extensions of observational pomset trace equivalence and observational history preserving bisimulation equivalence are both congruences under our refinement; and the syntactic and semantic refinements coincide up to the aforementioned equivalence relations with respect to a cpo-based denotational semantics.