在現有考慮不完美品質的經濟訂購批量（economic order quantity; EOQ）模型中，有將不良品假設為廢品出售，有的假設不良品可重加工成良品出售；而有些則假設不良品是次級品，而於進貨檢驗完畢後，以較低的價格ㄧ整批賣出。實際上，對於某些產品，在清理與丟棄不良品中損壞的部分後，所剩下的部分可抵用成良品，很自然地，這將影響剩餘良品的消費。本文之目的，是要針對不良品可抵用良品之產品，考慮供應商於某一時點會給予價格折扣與允許缺貨的條件下，建構最適EOQ模型。首先，針對供應商於某一時點會給予價格折扣的模型，本文依折扣時間之不同，考慮四種不同情境，以最大化折扣時零售商採取與不採取特殊採購之成本差額為目標，決定零售商於價格折扣時之最適訂貨策略；其次則是在考慮允許缺貨的條件下，以最小化年總成本為目標，決定零售商每週期之最適訂購量與最適允許缺貨量。本文並提供數值範例來說明此兩種存貨模型。

Among the existing EOQ models with imperfect quality, some assume that defectives can be treated as scrap items to sell, some assume that defectives can be reworked into non-defectives, while the others assume that defectives are second-class products and can be sold in a single batch at a lower price after the end of the inspection process. In practice, for some products, after getting rid of the bad portion of the defectives, part of each defective can be utilized as non-defectives. Naturally, this will affect the consumption of the remaining non-defectives. The main purpose of this paper is to investigate an EOQ models for each products under the condition that the supplier will give a one-time-only price discount and allowed shortage, where the defectives are screened out by a 100% inspection process and then can be sold in a single batch by the end of the inspection process. Moreover, we assume that a portion of defectives can be utilized as non-defectives and hence will reduce the consumption of the remaining non-defectives. Naturally, this will reduce the consumption of the remaining non-defectives. The optimal order policies associated with four kinds of effective times of the reduced price are obtained. As to the inventory models with shortage backordering, the present paper determines the optimal order quantity and the optimal backorder quantity per cycle of a retailer by minimizing the total cost per year as a goal. Finally, two numerical examples are provided to illustrate these two EOQ models.

摘要………………………………………………………………………………………i
ABSTRACT…………………………………………………………………………….ii
誌謝……………………………………………………………………………………..iii
表目錄………………………………………………………………………………......vi
圖目錄……………………………………………………………………………...…..vii
第一章 緒論………………………………………………………………….….….1
1.1 研究背景與動機…………………………………………………….….…1
1.2 研究目的………………………………………………………………..…5
1.3 本文架構…………………………………………………………..………5
第二章 不良品可抵用良品的EOQ模型…………………………………………7
2.1 符號與基本假設…………………………………………………………..7
2.2 模型推導…………………………………………………………………..9
2.3 小結………………………………………………………………………14
第三章 價格折扣下之經濟訂購批量…………………………………………….15
3.1 符號與基本假設…………………………………………………………15
3.2 模型推導…………………………………………………………………16
3.2.1 情境1（S1）的EOQ模型…………………………………………18
3.2.2 情境2（S2）的EOQ模型…………………………………………24
3.2.3 情境3（S3）的EOQ模型…………………………………………36
3.2.4 情境4（S4）的EOQ模型…………………………………………47
3.3 數值範例……………………………………………………………………55

第四章 允許缺貨下之經濟訂購批量…………………………………………….58
4.1 符號與基本假設…………………………………………………………58
4.2 模型推導…………………………………………………………………58
4.3 數值範例…………………………………………………………………69
第五章 結論與未來研究方向…………………………………………………….70
5.1 結論………………………………………………………………………70
5.2 未來研究方向……………………………………………………………71
參考文獻……………………………………………………………………………….73

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