Dynamic and flexible scheduling for a single machine

Abstract

Manufacturing and service enterprises rely heavily on Planning and Scheduling in decision making because they suffer from high cost resources and high workload situation making it vital to dynamically adjust and schedule resources. Different approaches were developed and used to tackle the scheduling problems. Most of these approaches are based on the use of combinatorial optimization to build deterministic schedules; however, these schedules are not efficient due to uncertainties such as processing times and machine failure rates which can create a volatile environment; thus, necessitating the need for the use of dynamic scheduling. The objective of this work is to propose a dynamic and flexible scheduling tool for the single machine case based on the overlapping load adjustment approach. We developed for this purpose a tool that generates all the possible schedules starting from a valid loading solution. We conducted an experimental study on a set of problems. We then studied the quality of the generated schedules in terms of schedule ending time of the last task (Cmax), number of tasks delayed and total processing time delay. The results showed that a very large number of schedules can be generated from the loading solution which shows the flexibility of the approach. In addition, the study showed the quality of the generated schedules with an average Cmax gap of 1.7% to the best generated schedule.