面對企業相間互競爭激烈及全球市場經營模型的劇變，如何做好有效的存貨管理以降低相關成本或增加利潤，已成為企業主要的追求目標。存貨的維持與控制，往往會影響企業資金調度的靈活性，甚至關係到企業的營運作業。供應商可藉由提供延遲付款的優惠來吸引零售商訂購更多的或品。在此延遲付款期間，零售商收到貨品時不需要立即付款，也不用支付任何利息，並可以利用此期間的銷貨收入賺取利息，一旦付款期限到期時，若零售商仍有貨品尚未出售，則需負擔庫存貨品的資金積壓成本。因此，如何在管理存貨過與不及中取得均衡點，已成為決策者重要的考量之一。 
    本文主要探討信用交易且允許缺貨的經濟訂購量存貨模型。文中包含四個章節，第一章說明研究動機與目的、文獻探討及研究架構三部份。第二章主要探討供應商提供二選一信用交易的付款方式給零售商，並探討當發生缺貨時，顧客願意等候欠撥的存貨模型。第三章延伸第二章的研究，將兩種延遲付款方式改為只有一種延遲付款方式，零售商的延遲付款優惠與訂購量有關，建立最適的零售商的存貨模型。對於本研究所建立的兩種存貨模型，我們分別利用代數方法求得最適解存在的充要條件。接著，建立演算法以利求解，並舉例說明求解的過程與做敏感度分析。第四章提出本研究的結論和未來研究的方向。

Face of firm fierce competitions and drastic changes in the global market business model. How to do effective inventory management to reduce the costs or increase profits has become a major goal to pursue.Inventory of maintain and control often affect the cash flow flexibility of enterprise even though operation of the business. Supplier offers permissible delay in payments to attract attraction retailer   order more items. During the trade credit period, retailer does not have to pay when receiving the products, and can use the sales revenue to earn interest. When the trade credit period is due, retailer has to pay interest for the products still in stocks. And, the delayed payments would produce capital opportunity cost for the supplier. Therefore, how to obtain the equilibrium point in inventory has become one of the important considerations.

    Economic order quantity inventory models with trade credit and allowable shortage are developed in this paper. Chapter 1 involves the motivation and objective of this thesis. In this chapter, literature review about relative research papers is also included. In chapter 2, we established an inventory model with two-part trade credit terms and allowable shortage. In Chapter 3, we extend model for Chapter 2, we established an inventory model with allowable shortage, and assumed that supplier offers an order-size dependent permissible delay in payments. The necessary and sufficient conditions of the existence and uniqueness of the optimal solutions for the two models are shown. In addition, an algorithm is provided to determine the optimal solution for each model. Numerical examples and sensitivity analyses are presented to illustrate the theoretical results. Chapter 4 the conclusion of this thesis and future research directions are proposed.

目錄
表目錄 III
圖目錄 IV
使用符號一覽表  V
基本假設  VI
第一章 緒論 1
  1.1 研究動機與目的 1
  1.2 文獻探討 2
  1.2.1 信用交易 2
  1.2.2 允許缺貨 3
  1.3 研究架構5
第二章 二選一信用交易且允許缺貨的經濟訂購量存貨模型 6
  2.1 前言 6
  2.2 符號與假設 7
  2.3 模型的建立 7
  2.4 模型的求解 11
  2.5 數值範例 26 
第三章 信用交易與訂購量有關且允許缺貨的經濟訂購存貨模型 33
  3.1 前言 33
  3.2 符號與假設 33
  3.3 模型的建立 34
  3.4 模型的求解 42
  3.5 數值範例 78
第四章 結論 83
  4.1 主要研究成果 83
  4.2 未來研究方向 85
參考文獻 86

表目錄
表2-1 範例2.1的最適解彙整表 28
表2-2 不同α值對最適解的影響 32
表3-1 範例3.1的最適解彙整表 79
表3-2 不同Qd與M值對最適解的影響 80

圖目錄
圖2.1當Mj≦t≦T時，零售商的存貨水準與計算利息的累積銷售量示意 9
圖2.2當t≦Mj≦T時，零售商的存貨水準與計算利息的累積銷售量示意圖 10
圖2.3當t≦T≦Mj時，零售商的存貨水準與計算利息的累積銷售量示意圖 10
圖3.1.1當Mj≦t＜T且T＜Td時，零售商存貨水準與計算利息的累積銷售量示意圖36
圖3.1.2當t≦Mj≦且T＜Td時，零售商存貨水準與計算利息的累積銷售量示意圖 37
圖3.1.3當t＜T≦Mj且T＜Td時，零售商存貨水準與計算利息的累積銷售量示意圖38
圖3.2.1當Mj≦t＜T且T≧Td時，零售商存貨水準與計算利息的累積銷售量示意圖39
圖3.2.2當t≦Mj≦T且T≧Td時，零售商存貨水準與計算利息的累積銷售量示意圖40
圖3.2.3當t＜T≦Mj且T≧Td時，零售商存貨水準與計算利息的累積銷售量示意圖40

參考文獻

中文文獻 :
1.陳舜堯 (2010) 。二階信用交易條件下零售商考慮多期現金折扣條件之最佳訂購策略。中原大學企業管理研究所碩士學位論文。
2.黃天受 (2005)。考慮允許信用交易下最佳訂購週期之研究。國立台灣科技大學工業管理系博士學位論文。
3.黃聖閔 (2009)。不良品重工、信用交易與部分欠撥下的生產政策。大同大學事業經營學所碩士學位論文。
4.楊建珉 (2008)。兩種延遲付款方式下允許缺貨且含有不良品的供應商與零售商之整合存貨模型。淡江大學管理科學研究所碩士學位論文。
5.蘇家嫻 (2007) 。信用交易條件下整合供應商與零售之供應鏈系統的最適訂購與運送策略。淡江大學管理科學研究所博士學位論文。

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