Abstract: Two time semantics,a strong semantics and a weak one,are usually adopted by time Petri nets in different application context.But they are limited in schedulability analysis because of scheduling consistency problem and sche-duling timeliness problem.This paper defined two characteristic conditions for consistency and timeliness,presented a time Petri net model with mixed semantics,and proved the mixed semantics model is more suitable for the schedulability analysis of real-time systems than the existing time semantics models.We further compared the timed bisimulation ability of the mixed semantics model and the strong and weak semantics models.

Key words: Time Petri nets,Mixed semantics model ,Characteristic conditions,Timed bisimulation