Application of Petri nets and a genetic algorithm to multi-mode multi-resource constrained project scheduling

Multi-mode and multi-resource constrained scheduling of a project is a comp lex task. This paper addresses the use of a Petri net as a modelling and sc heduling tool in this context. The benefits of Petri nets in project schedu ling are discussed. We propose extensions to Petri nets to suit scheduling of activities in a decision CPM. We also propose the use of a P-matrix for token movements in Petri nets. A genetic algorithm is used to find a better solution. Petri-net-aided software including genetic-algorithm-based searc h and heuristics is described to deal with a multi-mode, multi-constrained scheduling problem with pre-emption of activities.