Implicit Siphon Control and Its Role in the Liveness-Enforcing Supervision of Sequential Resource Allocation Systems

The work presented in this paper seeks 1) to correct and generalize some previously published results regarding the siphon control in PT-ordinary Petri nets (PNs) and, subsequently, 2) to employ this generalized framework in order to provide an alternative explanation of the way in which certain methodologies that have been proposed in the past enforce the liveness of a particular class of PT-ordinary PN-modeling resource allocation. The derived characterizations provide a unifying framework for analyzing and interpreting the aforementioned methodologies, and also, they reveal that approaches that have been considered as disparate in the current literature can actually be "mixed" toward the development of an ever richer set of liveness-enforcing supervisory-control policies for the considered class of PNs