商品需求率隨存貨水準變動的退化性存貨模式之研究

Research on the Deterioration Inventory Models for Items Demand Rate Varied by Inventory Levels

林佳英(Chia-Ying Lin)

指導教授 ： 李汶娟

長榮大學/管理學院/國際企業研究所/碩士(2008年)

https://doi.org/10.6833/CJCU.2008.00073

摘要

在日常生活中，存貨的退化（deterioration）是很普遍的現象，存貨可能因為需求耗用掉或是產品退化的現象而減少，因此在擬定這類物品的存貨策略時，除了需求因素外，產品退化所造成的存貨數量減少也必須加以探討。需求型態常被假設與時間有關，退化率也從一開始不被考量到後續學者常假設退化率與時間有關。另外，企業在發生缺貨時，只有部分的消費者願意等候缺貨待補，而另一部分的消費者可能不願等候而放棄購買或是轉向其他廠商購買。物品的需求率可分為固定與變動，在現實的日常生活中可以觀察到一種現象，一些量販業者會儘量將貨架上的物品擺滿，藉此刺激顧客的需求。對於這類型的物品，其需求通常與貨架上的存貨數量有關。
最後本研究根據商品需求隨存貨水準變動且與時間有關，且退化率為與時間有關的線性函數，缺貨情形假設為部份缺貨待補，並加入服務水準的考量，在假設條件下以求得最適訂購次數以及最適的服務水準能使總成本最小。而且，也提出兩個數值範例來說明存貨模型的求解過程，並分別對各參數做敏感度分析，以提供管理者作為決策之參考。

關鍵字

部分缺貨待補 ； 線性退化率 ； 服務水準

並列摘要

In the real world, the deteriorating of goods is a very common phenomenon. The deteriorating items result in the decreasing of the products. Therefore, the loss due to deterioration cannot be neglected.
Some customers would like to wait for backlogging during the shortage period, but the other would not. In fact, the longer the waiting time is, the smaller the backlogging rate would be.
The assumption of constant demand is not always applicable to real situations. For instance, it is usually observed in the supermarket that display of the consumer goods in large quantities attracts more customers and generates higher demand.
Hence, in this paper, we derive the EOQ model for inventory of items that deteriorate rate at a Rayleigh function, assuming the demand rate varied by inventory levels. The optimal solutions of replenishment number and service level are then determined. Numerical examples and sensitivity analyses are also provided to illustrate the solution procedure.
Key words：Backlogging、Linear deterioration、Service level

並列關鍵字

Backlogging ； Linear deterioration ； Service level

參考文獻

喬懷恩、蘇玲慧、黃惠民(民96)。考量時間限制與不良品之缺貨EOQ模式。先進工程學刊，第二卷第一期，頁21-26。

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Chakrabarty, T., Giri, B. C., & Chaudhuri, K. S. (1998). An EOQ model for items with weibull distribution deterioration, shortages and trended demand：An extension of Philip's model. Computers & Operations Research, 25(7), pp. 649-657

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