An MIP-based heuristic for scheduling projects with work-content constraints

Abstract

We consider the project scheduling problem where each project activity has a prescribed work content that must be completed by a so-called work-content resource, and the activities' resource usage may be varied over time. In each period, the amount of resources allocated to an activity must lie within a prescribed range and cannot be changed for a minimum number of consecutive periods. The amount allocated determines an activity's requirements for further resources. The activities must be scheduled such that the project makespan is minimized. For this problem, we devise an MIP-based heuristic that schedules the activities sequentially. To determine more efficient resource allocations among multiple activities, subsets of activities are rescheduled periodically. Our computational results for a standard test set from the literature indicate that the proposed approach provides very good feasible solutions for small-sized instances, and that it outperforms the state-of-the-art methods for large-sized instances.