Comparative study between methods for selection alternative routings in real time

The management of the queues by rules of priorities constitutes one of the simplest approaches and most used to dynamically schedule the tasks in a job shop. Unfortunately, one of the most important problems concerning the use of the rules of priority is the fact that no rule seems overall better than the others. To regulate these problems, we will combine rules of priorities and scheduling with selection of alternative routings in real time rule DMM. This combination will be realized according to the operating conditions, of the production targets and the state of the job-shop. Since the state of the workshop changes during time, we propose to analyze the state of the system each time a decision of scheduling must be taken, in order to take into account the real state of the job-shop. This approach will be implemented on a model of job-shop and will simulate by the simulation software ARENA.