On Persistency in Time Petri Nets

A transition of a (time) Petri net is persistent if once it is enabled, it can never become disabled through occurrences of other transitions until it is fired [5 ,15]. It is said to be effect-persistent if it is persistent and its effect (The effect of an enabled transition t in a marking M is defined by the set of transitions newly enabled by firing t.) is not affected by firing other transitions. This paper investigates some sufficient conditions for persistency and effect-persistency of transitions, in the context of time Petri nets (TPNs for short) that depend on the marking and the static/dynamic time information of the model. Then, it shows how to use these sufficient conditions to improve the partial order reduction technique of the TPN model.