Uncertain Resource Availabilities: Proactive and Reactive Procedures for Preemptive Resource Constrained project Scheduling Problem

Abstract

Project scheduling is the part of project management that deals with determining when in<br />time to start (and finish) which activities and with the allocation of scarce resources to the<br />project activities. In practice, virtually all project managers are confronted with resource<br />scarceness. In such cases, the Resource-Constrained Project Scheduling Problem (RCPSP)<br />arises. This optimization problem has become popular over the last few decades because of<br />its practical relevance to various industrial and research fields. Numerous procedures have<br />been developed in the literature for finding either optimal or heuristic solutions for the<br />RCPSP.<br />Resource constrained project scheduling problem under stochastic circumstances have been<br />considered in recent decades where uncertainty is modeled by means of activities' duration.<br />In this research we study an extension of basic stochastic RCPSP in which availability of<br />resources is not predefined. Activities follow preempt-resume mode in case of any disruption<br />due to resource infeasibility. A solution for this variant of RCPSP is defined in three steps by<br />utilizing heuristic procedures for creating initial schedule, adding time and resource buffers in<br />order to yield proactive schedule and applying reactive policies to encounter with unhandled<br />breakdowns. Computational experiments depict that proposed combined procedure achieve<br />significant performance gains over the use of each method separately.