傳統的存貨模型有著許多的限制，使其和現實情況並非吻合，在現實的情況下，大多數的存貨在持有過程中，存貨會隨著時間開始發生變質然而在生產的過程當中機器可能會故障。在我們的生產存貨系統中，考慮到損耗性產品以及機器會隨機故障並服從指數分配，而當我們的機器故障時，生產動作會停止，立刻進行維修，維修時間為一固定的期間。我們同時也用馬可夫鏈來計算出期望成本和服務水準限制式，利用給定固定服務水準最佳化此生產系統的最大存量以及安全存量，來達到期望成本最小化，期望成本包含了有設置成本、機器的維修成本、持有存貨成本、損耗產品成本和損失銷售成本。The traditional inventory model with too many assumptions and limitations, so that it and real world situation are not consistent. Under realistic conditions, the inventory item may be deteriorating and the production machine may breakdown.In this study, considers the product can deteriorate on constant rate and random machine breakdowns follow an exponential distributes. When machine breakdown, the production run will stop and immediately repair for a fixed period of time. We model the production-inventory system as a Markov Chain to formulate the expected total cost, incorporating a service-level constraint on the probability of a stock-out. The objective is to approximation the maximum inventory level and buffer stock that minimizes the expected total cost consisting of setup, corrective maintenance, holding, deterioration, and lost sales costs under conditions of continuous review, deterministic demand, and no shortages.
