In: Transactions of the Institute of Electronics, Information and Communication Engineers A, Vol. J71A, No. 4, pages 989-998. April 1988. In Japanese.
Abstract: The Petri net model can effectively be used for a hierarchical representation of the behavior of distributed systems. Specifically, by replacing stepwisely a transition in terms of a suitable subnet, one can obtain a desirable refined description of a given net model. A simultaneous refinement of a set of transitions which can fire concurrently is investigated and conditions are derived for the preservation of fundamental properties such as liveness and safeness in terms of the conditions on the original net and the substituted subnet.