A Modified Disjunctive Graph for Job-Shop Scheduling Problems with Bounded Processing Times and Transportation Constraints

Abstract In this paper, we propose a modified disjunctive graph to represent and help to address various types of job-shop problems with transport constraints. This graph contains positive and negative arcs for bounded processing times, and nodes for representation of processing tasks, transportation tasks and storage posts. Furthermore, solutions can be evaluated both by their makespan and by their total storage time for all operations if necessary. A modified shifting bottleneck procedure is used to solve the considered problems for minimizing makespan. To valid our approach, several types of benchmarks are tested, corresponding to flexible manufacturing systems and surface treatment facilities. Computational results show that the proposed graph and method are efficient and can deal with more general cases.