시스템 가용도를 고려한 수리부품의 재고수준 최적화

In almost all of the organizations, the cost for acquiring and maintaining the inventory takes a considerableportion of the management budget, and thus a certain constraint is set upon the budget itself. The previousstudies on inventory control for each item that aimed to improve the fill rate, backorder, and the expenditure oninventory are fitting for the commercially-operated SCM, but show some discrepancies when they are applied tothe spare parts for repairing disabled systems. Therefore, many studies on systematic approach concept consideringspare parts of various kinds simultaneously have been conducted to achieve effective performance for theinventory control at a lower cost, and primarily, METRIC series models can be named. However, the past studieswere limited when dealing with the probability distributions for representing the situation on demand and transportationof the parts, with the (S-1, S) inventory control policy, and so on. To address these shortcomings, theContinuous Time Markov Chain (CTMC) model, which considers the phase-type distributions and the (s, Q) inventorycontrol policies to best describe the real-world situations inclusively, is presented in this study. Additionally, by considering the cost versus the system availability, the optimization of the inventory level, basedon this model, is also covered.