A three-phase discrete event simulation with EPNSim graphs

In the simulation world view, there are three methods of constructing a simulation in common use: event scheduling, process orientation, and activity scanning (or three-phase approach). Because the three-phase approach has advantages of both modeling flexibility and modularity, the authors propose a simulation modeling tool, EPNSim, extended from the ordinary Petri Nets (PNs) to generate a language-independent pseudo code for the three-phase discrete simulation. Using the proposed method, the modeling processes of the three-phase discrete simulation can be concisely represented. In addition, it preserves the relative analytic properties of the original Petri net models (e.g. boundedness, liveliness, etc.), which are important for designing a system.