Solving dynamic resource constraint project scheduling problems using new constraint programming tools

Timetabling problems have been much studied over the last decade. Due to the complexity and the variety of such problems, most work concerns static problems in which activities to schedule and resources are known in advance, and constraints are fixed. However, every timetabling problem is subject to unexpected events (for example, for university timetabling problems, a missing teacher, or a slide projector breakdown). In such a situation, one has to quickly build a new solution which takes these events into account and which is preferably not too different from the current one. We introduce in this paper constraint-programming-based tools for solving dynamic timetabling problems modelled as Resource-Constrained Project Scheduling Problems. This approach uses explanation-based constraint programming and operational research techniques.