供應鏈管理之供給與需求不確定量化模式研究-以筆記型電腦產業為例

Research on Uncertain Quantitative Model of Supply and Demand of Supply Chain Management: Using Notebook Computer Industry as an Example

王信智(Shen-Tsu Wang)

指導教授 ： 劉志明 ； 林文燦

國立清華大學/工學院/工業工程與工程管理學系/博士(2008年)

摘要

筆記型電腦產業具有需求與供給不確定性情況存在，本研究發展的品類管理決策方法能解決顧客需求不確定性與零組件供給不確定性；另一方面，解決顧客需求不確定問題可使用延遲策略，製造商供應不確定所產生的傷害包括無法滿足顧客訂單上的產品型式，因此，本研究發展客製化之延遲策略模式預測客製化程度以解決顧客需求不確定與製造商供應不確定。

本研究提出適合台灣各種不同規模和經營環境的筆記型電腦產業之零組件管理方法，利用品類管理觀念以解決顧客需求不確定與供應商供給不確定性的問題，在關鍵零組件定義上，可使用單位零組件價格與供應廠商數目等因素作灰關連分析排列，排列出影響關鍵零組件之因素，接著以ABC零組件存貨權重之倉儲空間調整演算法、不同歸屬函數設定方法、解模糊化的德菲層級分析法與指數迴歸函數法，決定不同類別零組件之適當品類管理參數設定。透過所提出之品類管理決策方法，可以估計滿足客戶需求的存貨水準以解決需求不確定並且估計零組件從採購到入庫所需的前置時間以解決供給不確定，經由事先模擬各種可能之訂單變更狀況，來降低缺料風險及存貨之成本。
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另一方面，筆記型電腦產業之延遲策略應用，常以生產總成本最小、產品類型最大及平均組裝時間最小為量化目標，同時以顧客需求的零組件模組種類及零組件模組存貨數量為決策變數，因此，本研究構建一延遲策略多目標規劃模式，在需求不確定性函數中，則應用需求頻率及需求量分別服從卜瓦松分配及常態分配，由於各個目標式的單位不相同，因此，可以使用ε限制法求解多目標規劃問題；再來，利用多目標規劃所求得的生產成本與顧客基本需求的零組件模組等參數，求出最佳客製化程度與分析利潤函數中各因子間的相互關係，製y商可以依據市場需求的不同型式，配合製造商在供給不確定情況下想要達成的利潤，以製造商利潤最大為目標，訂定最合適的客製化程度。最後，以一家筆記型電腦廠商為例進行實證分析，提供筆記型電腦業者在執行品類管理決策方法與產品客製化程度決定；並分析各項參數的敏感度，提供決策者相關建議，以作為進行相關決策時的參考依據。

關鍵字

筆記型電腦產業 ； 需求與供給不確定性 ； 品類管理 ； 客製化程度 ； 多目標規劃模式

並列摘要

There is uncertain demand and supply in the notebook computer industry. This research develops a category management decision-making method can solve the problem of dealing with uncertain customer demand and supply. On the other hand, uncertain customer demand can be solved by using a postponement strategy. Manufacturers’ uncertain supply situation includes their failure to satisfy the product type specifications of clients’ orders. Thus, this research develops a postponement strategy of customization to predict the customization degree, in order to solve uncertain customer demand and manufacturers’ supply.

This research suggests a supply part management that is suitable for the notebook computer industry, with varied scales and operational environments in Taiwan, and solves the uncertainty of customer demand and supplier supply with the concept of category management. As for definitions of key supply parts, gray correlation sequencing analysis was conducted with unit price of supply parts and the number of suppliers, the gray sequencing correlation analysis was applied to sort the effect factors of key supply parts. Subsequently, with ABC of inventory weight re–allocation algorithm, different membership function constructions, Delphi analysis of defuzzification and exponential regression function method were used to determine the proper setting of category management parameters of supply parts in different categories. The category management decision-making method can be used to estimate the inventory level required to satisfy customer demand, to solve uncertain demand, as well as to estimate the lead time of supply parts from purchase to stock, thereby solving the problem of uncertain supply. By simulating different possible changes of orders, the risk of part shortages and cost of stock part can both be reduced.

In addition, postponement strategy in notebook computer industry tends to treat minimum total production cost, maximum product type and minimum assembly time as the objects of quantification. Besides, the kinds of supply part modules of customer demand and inventory amount of supply part module are regarded as the decision variables. Thus, this research constructs a postponement multi-objective planning model. In an uncertain demand function, demand frequency and demand amount are used to meet Poisson distribution and Normal distribution. Since the units of the objectives differ, multi-objective planning can be realized via ε-constraint method. Besides, optimized customization degree can be obtained and the correlation among the factors of profit functions can be analyzed according to the results of multi-objective planning considering the parameters of production cost and the supply part module of basic customer demand. Manufacturers can construct the most proper customization degree according to different types of market demand and the profit objectives in supply uncertainty, with the goal of maximizing profits. Finally, an empirical analysis was conducted on a notebook computer company to function as the reference for category management decision-making method and product customization degree of notebook computer companies. The sensitivity of the parameters was analyzed and related suggestions were provided.

並列關鍵字

notebook computer industry ； uncertain demand and supply ； category management ； customization degree ； multi-objective planning model

參考文獻

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