2003 Volume 16 Issue 9 Pages 451-460
Aiming at elimination of tardy jobs in a job shop production schedule, a simulation-based scheduling method with functions to control job allocation and capacity addition is proposed. In order to determine pertinent additional capacities and to control job allocations simultaneously, the proposed method incorporates the parameter-space search improvement (PSSI) method in which four parameters are introduced into the scheduling procedure. Furthermore, the proposed method adopts a local search method in order to reduce the computation time to search for the best solution on the parameter space. Performances of the proposed method with respect to the reduction of tardy jobs and the computation time are evaluated not only on a simple job shop model but also by using practical planning condition data prepared for an actual scheduling system. The results show that the proposed method gives significant performance for reducing tardy jobs as well as the amount of additional capacities and it is available for practical use.