Methodological Aspects of Action Refinement

The principle of action refinement refers to the implementation of abstract actions through more complex, concrete processes. In this paper we study the fundamental question how to use this principle in process algebraic system design. We formulate a methodological framework to express design under action refinement, and present two applications of this framework. The first application corresponds to the well-known interpretation of action refinement as an operator in the algebra, requiring a non-interleaving semantics; the second application is new, and results in a much more flexible notion of design, which is moreover compatible with the standard interleaving semantics.