存貨管理是一個企業成敗的重要關鍵之一，許多企業都希望擬定一個最適
訂購策略來達成最大的利潤賺得。在傳統的經濟訂購量模型假設零售商收到貨
品的同時必須付清貨款。而在實務上，供應商為了激勵零售商的訂購量，往往
會提供一段延遲付款時間給予零售商；對於零售商而言，不必負擔大量的資金
積壓，還可利用已銷售的收入去賺得利息。其次，傳統的經濟訂購量模型並沒
有將進貨物品中品質有瑕疵的情況納入考慮，這些瑕疵品非但不能賺取利潤，
反而會造成額外的成本支出。另外，檢驗貨品的過程中，可能會因為人為、技
術或環境等因素造成貨品檢驗錯誤，產生額外的處理成本以及利潤損失。這些
狀況均存在於現實的存貨管理中，也是決策者需面對及解決的問題，亦是值得
探討的議題。針對零售商的存貨管理問題，本論文將在存貨模型中，加入延遲
付款、貨品品質有瑕疵與檢驗錯誤等議題，探討這些議題對存貨管理的影響；
同時提出零售商在面對不同情況下，使得每年總利潤為最大的最適訂購策略。
    本論文研究兩個存貨模型，文中包含四個章節。第一章為緒論，包括研究
動機與目的、相關文獻探討及本文結構。第二章探討當供應商允許延遲付款且
貨品品質有瑕疵的情況下，零售商的最適訂購策略。第三章除延續第二章的概
念外，將檢驗錯誤的議題納入存貨模型中，研究檢驗錯誤對訂購策略之決定的
影響。針對兩模型分別找出最適解，並運用數值範例來說明模型的求解與應用
以及敏感度分析。最後，第四章提出本研究的結論和未來的研究方向。

In the traditional economic order quantity (EOQ) model, it is tacitly assumes that 
a retailer must pay for the items as soon as the items are received, and all items 
offered by a supplier are perfect quality items. However, in real business transactions, 
it is a common situation that a retailer receives some imperfect quality items from a 
lot, and additional costs are occurred by these imperfect quality items. In addition, a 
supplier may provide a permissible delay in payments to a retailer in order to 
encourage the retailer to increase order quantities. During the trade credit period, the 
account is not settled, and generated sales revenue is deposited in an interest bearing 
account. Moreover, the inspection errors due to the mistakes by human, techniques of 
inspection or environment are incurred and the penalty costs occur. In this thesis, a 
permissible delay in payments, defective items and inspection errors are taken into 
account when the optimal ordering policy is determined for maximizing retailer’s 
total profit.
    This thesis proposes two inventory mathematical models for the inventory 
system under trade credit. In chapter 2, we formulate an EOQ model with imperfect 
quality items when the supplier provides a permissible delay in payments. In chapter 3, we discuss an EOQ model with imperfect quality items and inspection errors when
the supplier offers a permissible delay in payments. For each model, some theorems 
are established to find the optimal ordering policy, numerical examples are given to 
illustrate the solution procedure and sensitivity analysis is reported. Finally, chapter 4 
provides the conclusions of this thesis and topics for future research.

目錄

表目錄	III
圖目錄	IV
第一章	緒論	1
1.1 研究動機與目的	1
1.2 相關文獻探討	3
1.2.1 延遲付款	3
1.2.2 品質有瑕疵	5
1.2.3 檢驗錯誤	7
1.3 本文結構	8
第二章	延遲付款下品質有瑕疵之貨品的最適訂購策略	9
2.1 前言	9
2.2 符號與假設	11
2.3 模型的建立	13
2.4 模型的求解	22
2.5 最佳解的決定	30
2.6 數值範例與敏感度分析	32
2.7 小結	39

第三章	延遲付款下品質有瑕疵及檢驗錯誤之貨品
         的最適訂購策略	40
3.1 前言	40
3.2 符號與假設	41
3.3 模型的建立	43
3.4 模型的求解	55
3.5 最佳解的決定	67
3.6 數值範例與敏感度分析	72
3.7 小結	81
第四章 結論	83
4.1 主要研究成果	83
4.2 未來研究方向	85
附錄	87
附錄一.	87
附錄二.	89
參考文獻	91

表目錄
表2-1：M變動下，最佳解的數值結果	33
表2-2：Ip變動下，最佳解的數值結果	34
表2-3：Ie變動下，最佳解的數值結果	35
表2-4：p變動下，最佳解的數值結果	36
表2-5：K變動下，最佳解的數值結果	37
表2-6：h變動下，最佳解的數值結果	38
表3-1：M變動下，最佳解的數值結果	73
表3-2：Ip變動下，最佳解的數值結果	75
表3-3：Ie變動下，最佳解的數值結果	76
表3-4：p變動下，最佳解的數值結果	77
表3-5：K變動下，最佳解的數值結果	78
表3-6：h變動下，最佳解的數值結果	78
表3-7：p1變動下，最佳解的數值結果	79
表3-8：p2變動下，最佳解的數值結果	80

圖目錄
圖2-1：Salameh and Jaber (2000) 之存貨系統	14
圖2-2：M≦t1≦T時之存貨水準、利息賺得及利息支付示意圖	15
圖2-3：t1≦M≦T時之存貨水準、利息賺得及利息支付示意圖	17
圖2-4：t1≦T≦M時之存貨水準及利息賺得示意圖	19
圖3-1：Khan et al. (2011) 之存貨系統	45
圖3-2：M≦t1≦T時之存貨水準、利息賺得及利息支付示意圖	46
圖3-3：t1≦M≦T時之存貨水準、利息賺得及利息支付示意圖	48
圖3-4：T≦M≦T+t1時之存貨水準及利息賺得示意圖	50
圖3-5：T+t1≦M時之存貨水準及利息賺得示意圖	52

參考文獻
中文部分：
張保隆、陳文賢、蔣明晃、姜齊、盧昆宏、王瑞探、黃明官 (2006)。生產管理。三版，台北市：華泰文化事業股份有限公司。


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