PERT scheduling with resources using qualitative simulation graphs

The Qualitative Simulation Graph Methodology (QSGM) is a general purpose qualitative discrete event simulation (QDES) framework, well suited to address the PERT scheduling with resources problem. The coverage property of QSGM has two important implications for the PERT scheduling problem. First, it means that all possible schedules are represented. Second, it means that, as long as the delay time intervals are not violated, we can characterize all possible outcomes of a decision that needs to be made in the schedule. This gives rise to the possibility of robust point-in-time scheduling decisions without needing to rerun the simulation in order to get the results.