半导体制造设备的维修调度研究

对半导体制造设备的维修调度问题进行了研究,提出了半导体故障设备维修人员分配法,解决了在有限的维修人员条件下制订优化的维修调度方案问题。有限维修人员条件下的半导体故障设备维修人员分配法分两步实现,首先通过求解模型得到一个优化的维修人员首次分配方案,再用最大优先度原则进行维修人员的再分配,直至全部的故障设备都得到维修。提出了用遗传算法求解用于维修人员首次分配的故障设备维修调度优化模型的方法,提出了用于进行维修人员再分配的最大优先度确定方法。最后,用一个实例示例了有限维修人员条件下的半导体故障设备维修人员分配法的实现过程,并对结果作了分析。

Long-release-interval-first real-time scheduling algorithm and its schedulability test

To fulfill the requirements for hybrid real-time system scheduling, a long-release-interval-first （LRIF） real-time scheduling algorithm is proposed. The algorithm adopts both the fixed priority and the dynamic priority to assign priorities for tasks. By assigning higher priorities to the aperiodic soft real-time jobs with longer release intervals, it guarantees the executions for periodic hard real-time tasks and further probabilistically guarantees the executions for aperiodic soft real-time tasks. The schedulability test approach for the LRIF algorithm is presented. The implementation issues of the LRIF algorithm are also discussed. Simulation result shows that LRIF obtains better schedulable performance than the maximum urgency first （MUF） algorithm, the earliest deadline first （EDF） algorithm and EDF for hybrid tasks. LRIF has great capability to schedule both periodic hard real-time and aperiodic soft real-time tasks.