透過您的圖書館登入
IP:3.227.239.160
  • 學位論文

含有不良品且需求率與售價有關的兩個倉庫存貨模型

The inventory models for two warehouses with defective items and price-dependent demand rate

指導教授 : 歐陽良裕

摘要


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。

並列摘要


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.

參考文獻


[1]Abad, P. L. (1988). Determining optimal selling price and lot size when the supplier offers all-unit quantity discounts. Decision Sciences, 19, 622-634.
[2]Aggarwal, S. P., and Jaggi, C.K. (1995). Ordering policies of deteriorating items under permissible delay in payments. Journal of the Operational Research Society, 46, 458-462.
[3]Benkherouf, L. (1997). A deterministic order level inventory model for deteriorating items with two storage facilities. International Journal of Production Economics, 48, 167-175.
[5]Bhunia, A. K., and Maiti, M. (1998). A two warehous inventory model for deteriorating items with a linear trend in demand and shortages. Journal of Operation Research Society, 49, 287-92.
[6]Burwell, T. H., Dave, D. S., Fitzpatrick, K. E., and Roy, M. R. (1991). An inventory model with planned shortages and price dependent demand. Decision Sciences, 22, 1187-1191.

延伸閱讀