A Multi-Heuristic GA for Schedule Repair in Precast Plant Production

A multi-heuristic schedule repair model for schedule conflict resolution is presented and its application in repairing the schedules of a prefabrication plant is described in this paper. The model combines heuristic strategies with Genetic Algorithms to repair schedules with resource constraints. The GA determines the “best ” sequence of resolving schedule disturbances using heuristic rules selected from a library of heuristics commonly used in industry. We compare quantitatively the advantages of using this model for schedule repair against existing single-heuristic schedule repair techniques with a multi-criteria evaluation function. Results on the macroscopic and microscopic levels are presented to understand the strengths and weaknesses of the model. Key words: application of planning and scheduling; dynamic scheduling.