本研究考慮在彈性維護以及惡化維護的限制之下，n 個不可分割的工作以及 m 台平行機台並求解最下化總完工時間。在本文中的排程問題，機台的狀態非連續可用的，意旨機台在連續工作一段時間後，必須進行機台的維護以避免機台 發生故障以及提升機台加工作業的品質。在以前的研究方向中，機台的維護以周期維護為主要研究，即所謂機台使用一段固定時間後必須進行維護作業，而近幾年為了提升機台的使用效率，發展出彈性維護周期的限制，意旨為在兩個連續維護作業的之間時間是不固定的，即每一次機台維護的開始時間是不確定的，本研究設立機台最小連續工作時間以及最大連續工作時間來符合彈性維護周期的限制。而除了彈性維護限制之外，為了更加符合實際工廠的環境，加了一項惡化維護的限制，意旨執行維護的時間會根據經過多久加工時間而變化，即上一次維護作業結束若經過較長的加工時間則下一次執行維護作業的時間則會加長，反之亦然。 我們提供分枝界限演算法來尋求本問題的最佳解，並且根據本文中五個propositions 以及lower bound 和upper bound 來提升演算法的效率，最後則是將使用電腦計算出問題的最佳解。 ;In this paper we consider the problem of scheduling of n nonresumable jobs on m identical parallel machines with deteriorating and flexible maintenance activities, and the objective is to minimize total completion time. In this paper scheduling, each machine is not continuously available. The machine must be maintained to prevent breakdown of machine and keep the quality of process jobs. In the past studies, the period maintenance activities is the main object. The period maintenance activity must be maintained after it continuously working for a period of time. In a recent year, develop to constraint of flexible maintenance in order to promote the efficient of machines. The flexible maintenance which means the starting time of unavailability period are decision variable together with jobs to be scheduled .This study given the minimum and maximum working time within any two consecutive maintenance activities correspond with flexible maintenance activity . In addition to constraint of flexible maintenance, correspond with manufacturing environment, we add the constraint of deteriorating maintenance. The deteriorating maintenance assume that the duration of each maintenance activity time depends on the running time. We propose a branch and bound algorithm to find the optimal solution. According to five propositions, lower bound and upper bound to promote the efficient of algorithm. Finally, we use computational analysis to calculate the optimal solution.
