Research Initiation: Scheduling Complex Dynamic Job Shops

该项目解决了大型作业车间的调度问题，该问题以动态作业到达、机器故障、到期日期相关的性能度量和不同类型的工作中心为特征。尽管这些问题具有重要的实际意义，但它们的困难使它们至今在很大程度上仍未得到研究。然而，随着工业环境中特殊问题结构的开发，提供了一种有前途的方法。对问题的动态方面使用了事件分类方法。它与一种近似方法相结合，可以为静态问题获得接近最优的调度。监控影响系统状态的事件，识别需要立即关注的事件（异常）。在没有例外情况的情况下，计划将定期生成，并在滚动的基础上实现。如果出现异常，系统会立即重新调度。提出了一种近似方法来生成各重调度点的调度表。这就需要为不同类型的工作中心制订有效的排班程序，从而产生一些迄今尚未广泛审查的排班问题。使用特定的工业环境，即半导体测试操作，作为研究工具，将能够从实际的角度评估拟议的研究。

This project addresses the problem of scheduling large job shops characterized by dynamic job arrivals, machine failures, due- date related performance measures and different types of workcenters. In spite of their practical importance, the difficulty of these problems has caused them to remain largely unstudied to date. However, with the exploitation of special problem structures present in industrial contexts provides a promising approach. An event classification approach to the dynamic aspects of the problem is used. It is combined with an approximation methodology that can obtain near-optimal schedules for a static problem. Events affecting system state are monitored and those needing immediate attention (exceptions) are identified. In the absence of exceptions, schedules are generated periodically and implemented on a rolling horizon basis. If an exception occurs, the system is rescheduled immediately. An approximation methodology is proposed to generate the schedules at the various rescheduling points. This requires the development of efficient scheduling procedures for different types of workcenters, leading to the formulation of a number of scheduling problems not extensively examined to date. The use of a specific industrial setting, that of semiconductor testing operations, as a research vehicle will enable the evaluation of the proposed research from a practical standpoint.