On the semantics of durational actions

This paper develops a mathematical framework to describe and reason about s emantic theories of processes where actions have a non-zero duration. The f ramework relies on the notions of reduction and observability and allows on e to naturally explain the possible choices to incorporate timing informati on in terms of process interaction mechanisms. The framework provides a par ameterized context where well-known and new theories can be formally compar ed and classified by a suitable instantiation of the parameters. A proof-te chnique to derive from the reduction semantics an equivalent SOS-based char acterization is also provided. (C) 2001 Elsevier Science B.V. All rights re served.