Scheduling function for management and optimization in production and service systems

Summary form only given. The point we are trying to explain in this communication is that a hard class of management problems needs appropriate optimization methodologies to be solved and that by using such methodologies one can obtain substantial gains and advances in the management of production and/or service systems. Such methodologies become more and more important in different management areas. More precisely, the first part of this communication is devoted to the presentation of some concrete problems related to the management field (scheduling problems). In such problems a general common structure consisting in sequencing, assigning, organizing and optimizing can be observed. Indeed, the scheduling function consists in organizing activities in a specific system imposing some rules to respect. The scheduling problems are essential in the management of projects, but also for a wide set of real systems (telecommunication, computer science, transportation, production...). More generally, solving a scheduling problem can be reduced to the organization and the synchronization of a set of activities (jobs or tasks) by exploiting the available capacities (resources). This execution has to respect different technical rules (constraints) and to provide the maximum of effectiveness (according to a set of criteria). Unfortunately, solving scheduling problems is not usually an easy task. The hardness of these problems is due to two aspects: the diversity of applications and the complexity of problems. Hence, it is not possible to construct a generic effective approach for solving them. Despite the great number of references and researchers dealing with these problems, it is well-known that most of them are hard to solve. The second part of this communication is devoted to the presentation of different exact and heuristic approaches (used for solving this type of problems).