Time: Thursday, November 14, 13.00
Place: B2-104, Fredrik Bajersvej 7
I will present a timed extension of Petri nets developed by Mogens Nielsen, Vladimiro Sassone and myself. In this model time parameters are associated with tokens and arcs carry constraints that qualify the age of tokens required for enabling. The novelty is that, rather than a single global clock, we use a set of unrelated clocks --- possibly one per place --- allowing a local timing as well as distributed time synchronisation. In order to give a motivation for such a formalism I will show how to model a simple producer-consumer system and a hardware architecture GALS (Globally Asynchronous, Locally Synchronous architecture). I will also present a formal definition of the model and investigate properties of local versus global timing, including decidability issues and notions of processes of the respective models.