模糊理論在供應鏈管理上之應用

Applications of Fuzzy Set Theory in Supply Chain Management

鄭雅云(Ya-Yun Cheng)

指導教授 ： 蕭育如 ； 徐旭昇

元智大學/工程學院/工業工程與管理學系/碩士(2001年)

摘要

本研究提出一個不確定環境中的模糊線型供應鏈模型，外在供應商交貨率及外部消費者需求是導致整條供應鏈不確定的主要變數，本研究利用模糊集合來描述線型供應鏈之不確定性，主要的討論目標是在合理的供應鏈總成本（使每一節點的持有成本及短缺成本最小）及可接受的產品交貨能力下來決定每一供應鏈存貨節點之最佳訂購量及存貨水準。此外，本研究討論兩種供應鏈存貨控制方法：（1）完全分權式控制法（2）部分協調式控制法，分別以這兩種供應鏈存貨控制方法提出了最佳模糊決策，並做供應鏈績效評估。研究所得結果如下：
(1) 以模糊集合來描述外在環境不確定性之模糊供應鏈模型，其最佳 訂購量為一組模糊訂購決策，依照外部消費者需求量之可能性及外部供應商交貨率之可能性的不同，會有不同的最佳訂購量。
(2) 當外部消費者需求量之可能性及外部供應商交貨率之可能性愈高時，最佳訂購決策愈確定；反之，當外部消費者需求量之可能性及外部供應商交貨率之可能性愈低時，最佳訂購決策愈模糊。
(3) 以完全分權式控制法來規劃線型供應鏈中每一存貨節點之訂購量及存貨控制時，會產生每一存貨節點之最佳訂購量皆相同之結果。
(4) 以部分協調式控制法來規劃線型供應鏈中每一存貨節點之訂購量及存貨控制時，和完全分權式控制法最大的不同是，會產生每一存貨節點之最佳訂購量皆不同之結果。
(5) 當外部消費者需求量之可能性及外部供應商交貨率之可能性愈高時，供應鏈之滿足率（Fill Rate）愈高；反之，當外部消費者需求量之可能性及外部供應商交貨率之可能性愈低時，滿足率（Fill Rate）愈低。
(6) 部分協調式控制法可使供應鏈系統產生較高之滿足率，因此若決策者將顧客滿意度視為決策關鍵因素，我們建議用部分協調式控制法來規劃線型供應鏈中每一存貨節點之訂購量及存貨控制。
(7) 完全分權式控制法可使供應鏈系統產生較好之成本控制，因此若決策者將成本控制視為決策關鍵因素，我們建議用完全分權式控制法來規劃線型供應鏈中每一存貨節點之訂購量及存貨控制。

關鍵字

供應鏈管理 ； 模糊集合 ； 存貨控制 ； 供應鏈績效評估

並列摘要

The study offers a fuzzy linear supply chain model that operates in an uncertain environment. It shows that the external supplier reliability and the external consumer demand are the major factors of the uncertainty. This study uses fuzzy sets to explain the uncertainty of linear supply chain, and its major goal is to determine the order quantities for each inventory in the supply chain, that give an acceptable service level of the supply chain at reasonable total cost (to minimize both holding cost and shortage cost in each stock period). In addition, two control concepts of the supply chain are treated: (1) fully decentralized control of each inventory and (2) partial coordinate control in the inventories. These two methods can individually turn out the best fuzzy decision and evaluate the supply chain performance as well. The results of this study are as follows.
(1)The best order quantities of the fuzzy linear supply chain model using fuzzy sets to explain the uncertainty is a fuzzy decision. It shows that the best order quantities will be relatively changed according to different possibilities of goods need from the possibilities of the external supplier reliability and the external consumer demand.
(2) When the possibilities of the external supplier reliability and the external consumer demand become increasing, the best order quantities turns out more clearly. On the other hand, when these two possibilities mentioned above become decreasing, the best order quantities turns out more fuzzily.
(3) By using fully decentralized control to plan order quantities and inventories in each inventory of the linear supply chain, it reflects that the best order quantities in each inventory turns out the same.
(4) By using partial coordinate control to plan order quantities and inventories in each inventory of the linear supply chain, it reflects that the difference compared with fully decentralized control is that the best order quantities in each inventory turns out differently.
(5) When the possibilities of the external supplier reliability and the external consumer demand become increasing, the fill rate of the supply chain is also relatively increasing. On the other hand, when the possibilities mentioned above become decreasing, the fill rate of the supply chain is decreasing too.
(6) Partial coordinate control can result a better fill rate of the supply chain. Thus, in case consumer’s satisfaction serves as the sole factor for decision making, then the method of partial coordinate control is recommended to use so as to plan order quantities and inventories in each inventory of the linear supply chain.
(7) Fully decentralized control can result a better control on the cost of the supply chain. Thus, in case cost control serves as the sole factor for decision making, then the method of fully decentralized control is recommended to use so as to plan order quantities and inventories in each inventory of the linear supply chain.

並列關鍵字

Supply Chain Management ； Fuzzy Sets ； Inventory Control ； Supply Chain Performance

參考文獻

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