Ichiro Inoue

An optimization-oriented method for simulation-based job shop scheduling incorporating capacity adjustment function

Abstract Aiming at the elimination of tardy jobs in a job shop production schedule, an optimization-oriented simulation-based scheduling method which incorporates capacity adjustment function is proposed. In order to determine the pertinent additional capacities and to control job allocations simultaneously, the proposed method incorporates the parameter-space-search-improvement method into the scheduling procedure. Furthermore, the proposed method includes a local search method in order to shorten the computation time to select an approximate optimal solution on the parameter space. The effectiveness of the proposed method from a practical viewpoint is demonstrated by using scheduling data obtained from a practical large-scale system.

A Simulation-based Production Scheduling Method for Minimizing the Due-date-deviation

A simulation-based scheduling method for minimizing the due-date-deviation is proposed on the basis of the combination of the BFHS (backward/forward hybrid simulation) method and the parameter-space-search-improvement method. A new schedule generation method named the BFHS/type-D is first developed, in which the information generated during the backward simulation is utilized to control operation-onset timings and job priorities in the forward simulation. Then, after investigation of the backward-simulation characteristics, two parameters are proposed to manipulate the simulation process systematically in relation to due-date-deviation. Furthermore, the best schedule with respect to due-date-deviation is searched for on the space spanned by the two parameters. Finally, the effectiveness and efficiency of the proposed method are demonstrated, not only on a simple job-shop model, but also on a practical large-scale system.