DSS for multiobjective project scheduling

The paper presents a decision support system (DSS) for multiobjective project scheduling under multiple-category resource constraints. It handles quite a general class of nonpreemptive scheduling problems with renewable, nonrenewable and doubly-constrained resources, multiple performing modes of activities, precedence constraints in the form of an activity network and multiple project performance criteria of time and cost type. The DSS is based on three kinds of heuristics: parallel priority rules, simulated annealing and branch-and-bound. The last algorithm can even yield exact solutions when sufficient processing time is available. Some parts of the system are interactive, in particular, the search for the best compromise schedule. Graphical facilities enable a thorough evaluation of feasible schedules. Methodological foundations of the system and the algorithms used in the calculation phase are first explained. Then, a functional description of the system is made. The last part presents results of three test problems in particular, an agricultural problem including 30 activities, multiple objectives and multiple-category resources.