論文主要針對多零件並聯系統，探討系統零件的最佳置換分群策略及系統零件執行置換時所帶來的整備成本對系統零件分群置換策略之影響。因為系統由零件以並聯方式所組合，所以零件的運作彼此之間為互相獨立，任一零件失效將不會影響系統的正常運作。當系統中任一零件失效時，皆以小修方式處理。一般來說，零件會隨著使用年齡的增加而退化，為了降低失效次數，零件應執行預防性置換作業。零件在執行置換的過程中會產生整備成本(外包專業團隊進行置換與設置的費用)，且整備成本相較高於維修成本。因此，本論文考慮對零件執行分群置換策略以降低整備成本，建構零件分群置換之數學模式，使得系統之總成本率最小，並以數值範例分析整備成本對系統零件分群置換策略之影響。

This paper investigates the effect of setup cost on the group replacement policies for a multi-component parallel system. Since multi-components are connected in parallel, each component operates independently without affecting the operation of the system. The failure of each component can be rectified by minimal repair. In general, a component may fail more frequently due to deterioration or aging. In this case, the component should be replaced at a certain time in order to reduce the number of failures. However, in this case when a replacement is outsourced and requires a team of professional technicians to perform the replacement action, the resulting cost is relatively high compared to the minimal repair cost. This cost is referred to the setup cost in this paper. Under this situation, the group replacement policy is considered to reduce the number of setups. In this paper, the mathematical model of group replacement policy for multi-component parallel system is derived such that the expected long run rate is minimized. Furthermore, the numerical examples are given to illustrate the effect of setup cost on the optimal group replacement policy.

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