Multi-mode resource-constrained project scheduling problem with activities overlapping

To reduce the project time and optimize the resource utilization, the multi-mode resource-constrained project scheduling problem with activity overlapping was proposed. The overlap and rework activity time factor matrix was designed to describe the relations between overlap and rework, and the multi-mode resource-constrained project scheduling optimization model with activity overlapping was proposed whose objective was to minimize the project's duration. A revised genetic algorithm based on specific schedule generation mechanism was presented to solve the model. Based on the classic double list encoding genetic algorithm, a preprocessing stage of the activity list was designed to improve its efficiency. The model and algorithm were demonstrated by using an example project and comparative experiments. The duration of project was tested and analyzed through full factorial design, which provided basis for decision makers.