Given that the overlapping of jobs is permitted, the paper studies the scheduling and control of failure prone production systems, i.e. so-called settings with demand uncertainty and job overlaps. Because a variable d...Given that the overlapping of jobs is permitted, the paper studies the scheduling and control of failure prone production systems, i.e. so-called settings with demand uncertainty and job overlaps. Because a variable demand resource is involved in the production and corrective maintenance control problems of the system, which switched randomly between zero and a maximum level, it is difficult to obtain the analytical solutions of the optimal single hedging point policy. An asymptotic optimal scheduling policy is presented and a double hedging point policy is offered to control simultaneously the production rate and the corrective maintenance rate of the system. The corresponding analytical solutions and approximate solutions are obtained. Considering the relationship of production, corrective maintenance and demand variable, an approximate optimal single hedging point control policy is proposed. Numerical results are presented.展开更多
The failure prone production systems are examined. For the hybrid systems, the failure of machines is unavoidable. By introduced the idea of purchasing extra capacity to the system, a so-call blockage hedging point is...The failure prone production systems are examined. For the hybrid systems, the failure of machines is unavoidable. By introduced the idea of purchasing extra capacity to the system, a so-call blockage hedging point is obtained. Meanwhile, a near-optimal method is presented to determine the optimal buffer sizes. The continuous flow model of the unreliable manufacturing systems is considered and the control point policy is involved in. Numerical results not only testify the method and show us its application but also to some extent show the impact of the machines＇ failure rate on the optimal buffer size.展开更多
基金This work was supported by the Project 973 (No.2002CB312200) and the National Natural Science Foundation (No.60404018).
文摘Given that the overlapping of jobs is permitted, the paper studies the scheduling and control of failure prone production systems, i.e. so-called settings with demand uncertainty and job overlaps. Because a variable demand resource is involved in the production and corrective maintenance control problems of the system, which switched randomly between zero and a maximum level, it is difficult to obtain the analytical solutions of the optimal single hedging point policy. An asymptotic optimal scheduling policy is presented and a double hedging point policy is offered to control simultaneously the production rate and the corrective maintenance rate of the system. The corresponding analytical solutions and approximate solutions are obtained. Considering the relationship of production, corrective maintenance and demand variable, an approximate optimal single hedging point control policy is proposed. Numerical results are presented.
基金This research is supported by the Project of the Great Technology Innovation of Gansu Province, China（2GS063-A52-005-01） and the Natural Science Foundation of Gansu Province, China（3XS062-B25-034）.
文摘The failure prone production systems are examined. For the hybrid systems, the failure of machines is unavoidable. By introduced the idea of purchasing extra capacity to the system, a so-call blockage hedging point is obtained. Meanwhile, a near-optimal method is presented to determine the optimal buffer sizes. The continuous flow model of the unreliable manufacturing systems is considered and the control point policy is involved in. Numerical results not only testify the method and show us its application but also to some extent show the impact of the machines＇ failure rate on the optimal buffer size.
