考慮原物料存貨成本之最佳存貨管理

Study on the Optimal Production Management Considering the Inventory Cost of Raw Material

蘇守梅(Shou-Mei Su)

指導教授 ： 林賜德

中原大學/理學院/應用數學研究所/博士(2013年)

https://doi.org/10.6840/cycu201300460

摘要

摘要
傳統的經濟生產批量(EPQ)模型是假設補充生產所需的原物料為及時的，而且相關費用僅包括生產作業成本、成品的存貨持有成本以及購買原物料的成本。但對於一個公司的管理者而言，還有一項成本問題是必須列入考慮的，那就是原物料的存貨持有成本。因為一般來講，若在週期開始時，即將所需的原物料一次購入，則原物料的存貨持有成本就會產生，所以將原物料的存貨持有成本加入相關總成本中，如此才算合理。此研究的主軸是將原物料的存貨持有成本加入經濟生產批量模型中，以此為基礎發展出新的模型結構，然後再依加入的變數後，各算出每一個模型的最低的相關總成本。
另外加入其他的變因有:成品是不良品或損耗性商品，以及用現值的觀點甚或隨機過程去討論衍生出來的經濟生產批量模型，讓模型與現實生活更加貼近一些。
對於環保問題，在近些年被熱烈地討論與重視，將來也仍然是重要課題。所以為了因應此問題，在原物料的部分將試著改用回收性原物料來取代新的原物料，以降低對環境的衝擊並增加在商業上的競爭力，所以此研究主要是以回收性的原物料為主，然後計算出模型的最佳相關總成本。
關鍵字: 存貨經濟生產批量(EPQ)、原物料、回收性、不良品、損耗性商品、現值、隨機過程

關鍵字

回收性 ； 不良品 ； 損耗性商品 ； 現值 ； 經濟生產批量(EPQ) ； 原物料 ； 隨機過程 ； 存貨

並列摘要

ABSTRACT
The traditional Economic Production Quantity (EPQ) assumes that the replenishments are instantaneous and the relevant cost only consists of setup cost, stock-holding cost of the finished goods and the purchasing cost of raw materials. To be a manager of a manufactory, one more issue that must be taken into consideration is the stock-holding cost of raw materials. Suppose all of the raw materials were bought at the beginning, the stock-holding cost for the raw materials would be generated. Regarding the factor, the stock-holding cost of raw material should be accounted into the relevant cost. The main concept of this research is to put the stock-holding cost of raw materials in the EPQ model. Based on this concept, we develop the new inventory models and the corresponding optimal policies.
There are some more elements will be considered for the EPQ models, they are described as follows: time value, deteriorating items, imperfect quality items, random planning horizon. The models will be useful and practical.
Environmental protection issues have been eagerly discussed and concerned in recent years, and they will still be in the years to come. To deal with these problems, the reusable raw materials are tented to replace the new raw materials to reduce the impact on the environment and increase the competition for business. Therefore most of the models are based on using reusable raw materials to find the optimal relevant cost. The upper and lower bounds are determined in this research in order to develop an algorithm used to compute the optimal cycle time. The analysis brings numerical examples into the algorithm in order to find the different cycle times. This research shows how the model is useful for current and future research.

Keywords: Inventory, Economic Production Quantity (EPQ), raw materials,reusable, imperfect quality items, deteriorating items, present value, random planning horizon

並列關鍵字

present value ； random planning horizon ； raw materials ； imperfect quality items ； Economic Production Quantity (EPQ) ； Inventory ； deteriorating items ； reusable

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