損耗性商品考慮不完美重工及價格變動之最佳補貨策略

Optimal replenishment policy of deteriorating items considering imperfect rework and varying price

古名尊(Ming-Tsun Ku)

指導教授 ： 黃惠民

中原大學/電機資訊學院/工業與系統工程研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200192

摘要

在現今市場環境中，許多產品都具有損耗之特性，例如：牛奶、蔬菜、電子元件等，均屬於損耗性之商品。而近幾年來損耗性商品已被廣泛的在討論，並且使用指數分配來描述損耗性商品之特性。但由於現今市場之競爭、多元化之產品及客製化之生產越來越受到重視，產品之生命週期日益縮短，廠商不外乎想要將自家商品在有限時間內放置在市場上進行銷售；而另一方面也由於產品生命週期縮短造成其預測時間也跟著下降，進而迫使整體供應鏈面臨迅速交貨之情形發生，因而間接造成不良品之生產提升。除此之外，由於產品之生命週期可以區分為四大階段，分別為：進入期、成長期、成熟期、衰退期，而產品之售價將會隨著時間而降低其銷售價格；而過去在探討損耗性商品之存貨將不完美生產及價格變動之議題納入探討者少之又少。
　　本研究有鑑於現今商品之特性，將針對單一產品具有損耗之特性並伴隨著不完美重工及價格變動下，建構出最佳補貨策略之存貨模式。並透過數學軟體Maple 13及Excel 2007進行求解運算，以求得其單位時間內總成本最小化為目標之最佳檢驗時間及最佳訂購次數並推導出最佳訂購數量，後續並透過數值範例及敏感度分析來證明本研究所提出模型之可行性及合理性，並說明各項參數對於模型之影響程度。

關鍵字

損耗性商品 ； 價格變動 ； 重工 ； 不完美生產

並列摘要

In recent years, studies on deteriorating inventory models have been investigated by many researchers due to uncertainty in demand and rapid improvement of technology. Deteriorating items are characterized as short life cycle products that lose its value over time due to changes in its natural attributes, technology and market preferences. Such items are medicine, food, chemicals, electronic components, and fashion items. The item’s product life cycle can be divided into four stages: introduction, growth, maturity, and decline stage. Generally, items deteriorate with time in an exponential distribution where the item’s price decreases over time. In today’s competitive environment, many industries produce in multiple products and utilize customized production to deliver high quality products rapidly at efficient cost. However, imperfect production and varying prices are unavoidable. In the past, few studies have explored deteriorating items with imperfect production and varying price. Hence, this study proposes a deteriorating inventory model that considers the aforementioned conditions.
　　In this study, we develop an optimal replenishment policy for a single deteriorating item with imperfect production and varying price. The objective of this study is to find the ideal inspection time and number of orders in order to get the optimal order quantity resulting in minimum cost. The inventory model is solved by Maple 13 and Excel 2007. Numerical example and sensitivity analysis are given to validate the model and to illustrate the changing effect of the parameters value on the optimal inventory cost. This study provides managerial insights on achieving an optimal replenishment policy for deteriorating items that can be adopted by enterprises in the supply chain.

並列關鍵字

Deteriorating items ； imperfect production ； rework ； varying price

參考文獻

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