在許多企業的營運資金裡，存貨成本通常佔有相當大的比重，因此若能做好存貨管理，除了可以減輕企業資金的壓力，還能間接增加公司獲利能力。如何在低庫存管理成本、高服務品質與生產績效間尋求平衡點，一直是目前企業界所努力追求的目標。1915年Harris率先提出「經濟訂購量」（EOQ）公式，但其模型假設條件太多，導致實際運用時，受到很大的限制，因此陸續有許多學者針對不同的條件提出各種存貨模型。
    傳統的EOQ模型假設企業擁有單一且無容量限制的倉庫，然而，在現實情況中，零售商的自有倉庫時常有固定的容量限制，當企業採購大量的物品時，受限於自有倉庫的容量，此時可能需要外租倉庫以存放額外的存貨。再者，傳統模型並沒有考量到進貨物品中含有瑕疵品的情況，由於機具設備老舊、原料品質良莠不齊而可能造成零售商的進貨物品中含有瑕疵品。另外，物品在市場上的需求並非是固定維持不變的，需求率可能與產品的價格存在著密切的關係，因此考慮物品的價格對市場需求率的影響將能使模型更加完整。
    全文包含兩個存貨模型，第二章假設供應商為了吸引顧客增加訂購數量而提供數量折扣。第三章延續第二章的基本假設，將供應商吸引顧客多量訂購的策略修改為提供延遲付款的信用交易。兩個模型皆以使單位時間銷售總利潤最大為其目標，並各自發展出一個演算法以利求解。最後以數值範例說明求解過程並做敏感度分析，以暸解各參數值的變動對最適解的影響。第四章為結論，對本文各章所建構的存貨模型作一總結，同時提出未來的研究方向。

The inventory always have a higher proportion of the cost in a company, therefore having a good management of inventory control could make a higher profit. The goal of the company is to balance the low-inventory control cost, high quality service and production performance. In 1915, Harris developed an EOQ model with many assumptions, therefore it was difficult to be applied in the real world. However, many scholars modified its assumption according to different conditions.
Traditional EOQ model assumes retailers own a warehouse without capacity limitation. However, in the real world company has fixed capacity warehouse. Thus while the company has a large stock because of the large order, they need to rent another warehouse to hold excess stocks. Moreover, traditional EOQ model does not consider defective items, even poor-quality items do exist during production procedure. In addition, the demand rate does not always stay constantly, it would change with different price. Thus, considering price-dependent demand will make model more reasonable.
In this thesis two inventory models are formulated. In Chapter 2 we assume that supplier provide quantity discount for retailers, In Chapter 3 we extend the model in chapter 2 with supplier allows a specified credit period to the retailer for payment without penalty. The goal of two inventory models is to determine maximize the profit per unit time. For each inventory model, we establish algorithm to determine the optimal strategy and numerical examples are given to illustrate the solution procedure. Also, sensitivity analysis is conducted for the parameters of the models. Finally, Chapter 4 provides the conclusions of this thesis and some suggestion future research.

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  3
1.3 研究方法  8
1.4 研究架構  8
第二章 數量折扣，需求率與售價有關且進貨物品中含有不良品的兩倉庫存貨模型  10
2.1 前言  10
2.2 符號說明與假設  11
2.3 模型的建立與求解  12
2.4 數值範例  21
第三章 考慮延遲付款，需求率與售價有關且進貨物品中含有不良品的兩倉庫存貨模型  29
3.1 前言  29
3.2符號說明與假設  30
3.3 模型建立  31
3.4 模型求解  38
3.5 數值範例  45
第四章 結論及後續研究  56
4.1 結論  56
4.2 後續研究方向  57
參考文獻  59
 
表 目 錄

表2.1	不同訂購數量下的單位購買成本  21
表2.2	利用演算法的求解程序算出TEPU(Q*,S*)  22
表2.3	自有倉庫的最大容量w值變動下的最適解  23
表2.4	訂購成本k值變動下的最適解  24
表2.5	外租倉庫單位時間單位物品的儲存成本hR值變動下的最適解     24
表2.6	自有倉庫單位時間單位物品的儲存成本hw值變動下的最適解 25
表2.7	需求函數中參數值a值變動下的最適解  25
表2.8	需求函數中參數值b值變動下的最適解  26
表2.9	期望不良率Mp值變動下的最適解   26
表2.10	敏感度分析  28
表3.1	例題3.1的求解過程  46
表3.2	自有倉庫的最大容量w值變動下的最適解  47
表3.3	外租倉庫單位時間單位物品的儲存成本hR1值變動下的最適解   47
表3.4	自有倉庫單位時間單位物品的儲存成本hw1值變動下的最適解  48
表3.5	需求函數中參數值a值變動下的最適解  48
表3.6	需求函數中參數值b值變動下的最適解  49
表3.7	所賺利息的利率Ie值變動下的最適解  49
表3.8	所需支付利息的利率Ic值變動下的最適解  50
表3.9	延遲付款的信用交易期限M值變動下的最適解  50
表3.10	物品的單位購買價格c值變動下的最適解  51
表3.11	不良率p值變動下的最適解  52
表3.12	敏感度分析  54

 
圖 目 錄

圖2.1	外租倉庫及自有倉庫同時進行篩選的存貨系統  12
圖3.1	T≧M時之存貨系統  32
圖3.2	T≦M時之存貨系統  33

中文文獻

[1]賀照鈞，（2004），考慮不完美品質及在兩個倉庫容量限制下之經濟生產批量，國立台灣科技大學，工業管理研究所碩士論文。

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