Parametric Action Reenement

A notion of action reenement is deened in an event-based model, which handles causal-ities in a less strict way than most existing approaches. The reenement operator is parameterized by a dependency relation on the actions. Inheritance of causality is based on that parameter. Furthermore in the same way a parameterized sequential composition operator is deened and consistency of the two operators is shown. Special emphasis is laid on the modelling of deadlocks: for the deenition of the two new operators it is crucial to know which actions are discarded when a process deadlocks. Standard reenement can be retrieved as a special case by using a total dependency relation. Local and global properties of processes and relationships between processes which are preserved under parametric reenement are investigated. Finally, the usefulness of this new notion of re-nement is demonstrated by two examples.