In: Computer Systems Science and Engineering, Vol. 5, No. 4, pages 205-214. October 1990.
Abstract: A model of concurrent, time-dependent software systems is introduced which is based on a combination of hierarchical graph (h-graph) theory with timed Petri nets. Termed the HG model, it is intended to support a variety of performance studies of real-time concurrent computations. Concurrent control flow on the HG model is represented by a marked, timed Petri net. The formal concepts on which the HG model is based are presented, and its utility in calculating time bounds for procedure call executions is illustrated. This computation uses the synchronous concurrent reachability graph, which is a restricted form of the classical Petri net reachabilty graph.
Keywords: procedure execution time (in a) synchronous net; concurrent, time-dependent software system; hierarchical graph; timed net; performance; synchronous concurrent reachability graph.