免疫演算法於連續零件系統之最佳維護策略的研究

An Immune Algorithm For The Optimal Maintenance Policies Of Consecutive Component Systems

王友倫(Yu-Lun Wang)

國立虎尾科技大學/管理學院/工業工程與管理研究所/碩士(2006年)

摘要

近年來利用維護策略保持系統穩定性已在工程上扮演一個不可或缺的重要角色，但是當系統變得龐大且複雜時，系統可靠度將愈來愈難掌控，維護策略無法有效的實施，進而影響到系統成本與壽命等，嚴重者甚至會影響到企業整體績效。目前業界經常需要運用各種工程系統，如通信系統、航空器、核能反應爐、醫療設備、電腦資訊系統等，這類系統需要極高的可靠度，但經常因為使用年齡或年限而導致零件老舊(aging)或退化(deteriorating)，以致最後發生故障或失效，倘若子系統失效故障，導致整個系統發生問題，將造成無法挽回的後果。
衆所皆知，串聯(series)、並聯(parallel)系統為我們常用的兩種系統，其中當串聯系統之零件規模較大時其可靠度一般而言均相當低，另一方面並聯系統雖有相當高的可靠度但相對地成本也會迅速上升，在1980年代有學者提出一個嶄新的連續零件系統(consecutive-k-out-of-n:F System)，此種系統包含n個直線相互連接的不同零件，當其中連續k個零件失效時系統即為失效。
在本研究中將探討此類更一般化連續零件系統之最佳維護策略的問題，其最佳化目標函數包含系統長期維護成本與系統失效成本，窮舉法雖然可以獲得此類問題之最佳解，然而當問題維度稍大時，其電腦運算時間增加極為迅速。本研究之主要目的為提出一個新的免疫演算法，來解決連續零件系統之最佳維護策略的問題。除此之外，針對不同維護程度、維護成本及不同參數k、n，我們以免疫演算法與窮舉法作相關的數值分析，結果顯示新提出之免疫演算法均能獲得良好之結果。

並列摘要

The series and parallel systems are two well known systems. When the system size is larger the system reliability for series system will be very low, on the other hand, the parallel system will be very expensive. In 1980s, a new system called consecutive-k-out-of-n:F system was proposed and the system is failed if and only if there are n linear consecutive components are failed.
In this paper, we investigate the optimal maintenance policy for the consecutive component systems whose objective function includes long run expected average cost per period. Bruce force methods can be used to obtain the optimal policy however it is very time consuming when the problem size is larger. The main objective of this paper is to propose a new immune algorithm for finding the optimal maintenance policy. In addition, numerical results for various combinations of parameters are reported and compared. It is shown that the proposed immune algorithm performs well for all test problems.

參考文獻

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