臺灣博碩士論文加值系統

在存貨模型中，一面生產一面銷售的模式稱之為經濟生產批量存貨模式（economic production lot size，EPLS）。除了傳統的固定生產率之外，在某些情況下，生產率可能會隨時變動，例如隨著市場需求率而做修正，或者隨著存貨水準改變而做調整。
再者，在諸多產品中，退化是一種非常普遍的現象，所謂退化即產品因衰退或腐敗後而不能執行其原有功能，例如藥品、揮發性液體及蔬果食物等，使得存貨數量除了因為需求的耗用而減少外，也因為產品的退化而降低；因此在探討此類產品時，因產品退化所造成的損失是不能被忽略的。此外，一般新品牌上市時，需求率常隨時間的向前移動而遞增，直到某一時點之後，需求即呈平穩狀態，在文中即以斜坡型函數表示之。
基於以上的考量，本論文建構了三個有關固定退化率的經濟生產批量存貨模式，在第二章中，我們首先討論生產率為固定常數的生產批量存貨模式；在第三章及第四章中，則進一步將生產率分別考慮為跟需求率有關及跟存貨水準有關的生產批量的存貨模式。三個模式皆以單位時間平均成本最低為目標，利用傳統最佳化理論進行求解，求出最適存貨策略。最後，舉例說明上述模式的求解過程並對各參數做敏感度分析。

Manufacturing and selling products simultaneously is called economic production lot size model ( EPLS model ) in the inventory model. Beside traditional fixed production rate, production rate may change at any time in some case. For example, it may adjust by the market demand or by the inventory level.
Besides, deterioration is a common phenomenon in many products. It is defined as decay or damage such that the item cannot be used for its original purpose (eg. Drugs, volatile liquids and food stuff, etc.). it makes the inventory decrease not only by the demand, but also by the deterioration. As a result, when discussing this kind of productions, the loss due to deterioration cannot be neglected. Besides, we use the ramp type function to explain the situation when a new brand of consumer goods coming to the market. The demand rate for such items increases, with time up to certain time and then ultimately stabilized and become constant.
Due to the factors considered above, three EPLS models about fixed deterioration rate have been formulated in the study. In chapter 2, the EPLS model under the assumption of constant production rate is discussed. Chapter 3 discusses the production rate which depends on demand rate in EPLS model. Chapter 4 discusses the production rate which is a function of the on-hand inventory level in EPLS model. We discuss three models and cost functions respectively to find out their optimal inventory strategies. Finally, numerical examples are provided to illustrate the proposed model and sensitivity analysis is also provided.

第一章緒論……………………………………………………………1
1.1 研究動機與目的…………………………………………………1
1.2 文獻探討…………………………………………………………2
1.3 研究方法與求解步驟……………………………………………3
1.4 研究架構…………………………………………………………3
第二章生產率固定且需求率為斜坡型函數之退化性產品的存貨模式4
2.1 符號及假設…… ………………………………… 4
2.2 模式之建立及求解……………………………………………6
2.3 數值範例…………………………………………………16
2.4 敏感度分析………………………………………………17
第三章生產率與需求有關且需求率為斜坡型函數之退化性產品的存貨模式………………………………………………………………………27
3.1 符號及假設……………………………………………27
3.2 模式之建立及求解……………………………………27
3.3 數值範例………………………………………………37
3.4 敏感度分析……………………………………………38
第四章生產率與存貨水準有關且需求率為斜坡型函數之退化性產品的存貨模式…………………………………………………………………49
4.1 符號及假設…………………………………………………...49
4.2 模式之建立及求解…………………………………………...49
4.3 數值範例……………………………………………………...61
4.4 敏感度分析…………………………………………………...62
第五章結論及後續研究方向………………………………………73
5.1 結論………………………………………………………...73
5.2 後續研究方向…………………………………………...74
參考文獻……………………………………………………………75

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