Synthesis of Nets With Inhibitor Arcs

. The synthesis problem for Petri nets consists in the construction of a net system whose behaviour is specified by a given transition system. In this paper we deal with the synthesis of elementary net systems extended with inhibitor arcs, i.e. arcs that test for absence of tokens in a place. We characterize the class of transitions systems corresponding to the sequential execution of these nets, which is a proper extension of the one obtained by the execution of nets without inhibitor arcs. Finally, we try to minimize the number of inhibitor arcs; we look for conditions guaranteeing that an inhibitor arc is really used, i.e. its presence influences the behaviour of the net. 1 Introduction In recent years there has been a growing interest in contextual nets. Besides the ordinary arcs, in contextual nets also some other arcs types are considered: arcs that just test for presence of tokens (Montanari and Rossi [9] argue that in this way the potential concurrency of a net is reflected, w..