Transformation rules for P-time Petri nets

P-time Petri nets have been developed to deal mainly with operation time constraint systems. We propose a set of reduction rules aimed at transforming the system being modeled into a simpler, but equivalent one, while preserving some properties to be analyzed. Each of these reduction rules are special cases of the corresponding rules, originally introduced by G. Berthelot (1983; 1985) for autonomous Petri nets. They preserve liveness, safeness of the underlying autonomous Petri net, in addition to timing properties (performance evaluation, live token sequences, etc.). We illustrate the use of reduction rules in order to reduce the computational complexity of scheduling problems. The problem considered consists of determining the sequence of requests to ensure the consistency of a repetitive supervision of a distributed control.