以現值觀點探討不同供應商採信用策略之最佳存貨模式

Research of Optimal Inventory Policy under Different Supplier Credit Policies with Taking Account of Present Value

邱靜芳(Jing-Fang Chiou)

指導教授 ： 林賜德

中原大學/商學院/企業管理研究所/碩士(2010年)

https://doi.org/10.6840/CYCU.2010.00563

摘要

存貨系統的管理牽涉到相當多財務現金流量的發生，必須考慮貨幣的時間價值以適當的反應機會成本，但如果忽略資金成本的時間價值，將與實際存貨管理不符。此外，若再加上買賣時允許信用交易的付款方式，則延後付款所引起的金錢時間價值更值得重視與研究。
在本論文中，供應商信用策略分為二大類：第一類供應商信用策略，訂購數量的多寡與信用交易是互相獨立的(策略I)；另一類此供應商信用策略的信用交易與訂購數是互相連結的(策略II：供應商要求於下訂單時需支付固定的訂金，貨到時再支付餘款。策略III：貨到時才需支付貨款)。後面的這一類的信用策略中，供應商使用信用交易策略來鼓勵買方大量訂購。也就是說，只有在大量訂購下才會有信用交易期限的存在，且替代了數量折扣。本研究將上述策略I、II、III分別加入考慮金錢的時間價值，並利用分析的方法，計算出當規劃週期為無限時，其總相關成本之現值，再進一步求出當總相關成本之現值最小時的最佳訂購週期時間，使模型更能真實反映貨幣時間價值的假設。
最後，本文對不同策略列出其數值範例，說明如何計算最佳訂購週期時間、最佳訂購量及總相關成本之最佳現值。並與Khouja & Mehrez之未考慮現值存貨模式下計算出的最佳訂購量相比較，進而得到結論為：以現值計算之存貨模式，最佳訂購量大都略少於未考慮現值之存貨模式。因此，金錢的時間價值因素的確會對企業的存貨策略造成影響。

關鍵字

信用交易 ； 最佳訂購週期時間 ； 總相關成本函數 ； 現值

並列摘要

The management of the inventory system involves lots of financial cash flow. We must consider the time value of money to react the opportunity cost properly. However, the time value of the capital cost is being neglected that cannot match with actual inventory management. In addition, the delay in payment take with the time value of money will be taking to study worthy.
The supplier credit policies addressd in this paper fall into two categories: the first type is one in which credit terms are independent of the quantity ordered. (Policy I); the secod type is one in which credit terms are linked to the order quantity. (Policy II：suppliers require affixed deposit on orders when they are placed and the rest of the amount when they are delivered. Policy III：pay full amount when the order is received.). In the latter case, suppliers use favorable credit terms to encourage customers to order large quantities. In other words, the favorable credit terms apply only at large order quantities and are used in place of quantity discounts. In this paper, we put the present value in the above supplier credit policies to calculate the present value of total cost and the ordering cycle time in the optimal cycle time to make the model can reflect assumption of the monetary time value truly.
Finally, some numerical examples are used to illustrate the effects of different credit policies in this paper. Compare with the best order quantities that are calculated from the present value of the inventory model in this paper are less than the inventory model of Khouja & Mehrez. So, Time value of money will really affect the inventory policy of enterprises.

並列關鍵字

Trade Credit ； Optimal Cycle Time ； the Function of the Total Relevant Cost ； Present Value

參考文獻

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