Kleene Theorems for Free Choice Automata over Distributed Alphabets

摘要

We provided (PNSE'2014) expressions for free choice nets having distributed choice property which makes the nets direct product representable. In a recent work (PNSE'2016), we gave equivalent syntax for a larger class of free choice nets obtained by dropping distributed choice property. In both these works, the classes of free choice nets were restricted by a product condition on the set of final markings. In this paper we do away with this restriction and give expressions for the resultant classes of nets which correspond to free choice synchronous products and Zielonka automata. For free choice nets with distributed choice property, we give an alternative characterization using properties checkable in polynomial time. Free choice nets we consider are 1-bounded, S-coverable, and are labelled with distributed alphabets, where S-components of the associated S-cover respect the given alphabet distribution.