“…Petri nets [3], as a major mathematical model, have been applied to many problems in discrete event systems [4]- [10], such as modeling and analysis [11], [52], control [12]- [17], opacity verification and enforcement [18], [19], scheduling [20]- [28], [50], [51], performance evaluation [29], [30], [53], fault identification and diagnosis [32], [33], [61], [62], validation of various properties [18], [19], [54], and deadlock analysis and control [31], [32], [34], [35], [45]- [48].…”