The set-covering approach by Piroddi et al. may reach the optimal number of states among all approaches for a well-known benchmark using a siphon-based approach without reachability analysis. However, the resulting model is a generalized Petri net incurring extra cost in system verification, validation and implementation. The only improvement is to replace two monitors with weighted arcs by two new monitors without weighted arcs. We develop a theory for explaining the cause of state losses and providing the foundation for the above improvement model.
Advanced Materials Research (Volumes 605 - 607) , Chapter 11: Control Technologies and Intelligent Systems, pp.1831-1835