Optimal Lot-Sizing Policy for Time-Varying Demand with Shortages and Deterioration

退化性物品考慮缺貨及變動需求的最佳庫存策略

王勝本(Sheng-Pen Wang)

《工業工程學刊》 20卷5期 (2003/09) Pp. 449-456

摘要

長久以來，在庫存問題的討論中缺貨項目經常被假設為完全欠撥待補或是完全不補兩種極端情形，但是較為合理的模式應該能描繪出願意接受缺貨待補的比率是隨著等侯時間增長而減少的特性。本文對一般切合實際的庫存模式定義了適當的部分欠撥待補率，並考慮因喪失銷售機會而引發的成本。我們證明了在以達到最小總成本的最適解正是能將利潤作最大化，且最佳的補貨策略具有單調的特殊性質。此外，藉由考量首先開始的補貨循環中的各項成本關係，我們提供了簡單的啟發演算法以期能良好地估計第一個補貨點。

關鍵字

庫存 ； 退化性商品 ； 部分欠拯待補 ； 機會成本

並列摘要

It has long been assumed that the shortages in inventory systems are either completely backlogged or totally lost. However, it is more reasonable to characterize that the longer the waiting time for the next replenishment is, the smaller the backlogging rate would be. In this paper, we define an appropriate partial backlogging rate to make the present model general and realistic for deteriorating items with time-varying demand and we also consider the opportunity cost due to lost sales. We show that the optimal solution minimizing the total cost is exactly the one that maximizing the profit. In addition, we verify that the optimal replenishment policy still possesses the monotonicity properties. Moreover, to generate a good estimation of the first replenishment time, we provide a simple heuristic by considering a relation between the cost components in the first cycle.

並列關鍵字

inventory ； deteriorating items ； partial backlogging ； opportunity cost

參考文獻

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