延遲差異化系統之設計與分析

Design and Analysis of Delayed Differentiation System

謝兆宇

指導教授 ： 蘇哲平

國立清華大學/工學院/工業工程與工程管理學系/碩士(2009年)

摘要

由於全球化，企業之間的競爭越來越激烈，因應來自全世界各地不同客戶的要求，企業供給的產品有多樣化的趨勢，因此如何有效快速，並以合理的價格滿足客戶客製化的需求變成重要的研究議題，而延遲差異化有潛力成為可行的方法之一。本研究結合預製與訂製兩種生產策略設計一個延遲差異化生產系統。在系統第一階段中，我們利用組裝線預製共用元件，在第二階段則利用零工式訂製生產策略，在顧客訂單來到之後進行最後的客製化。本研究運用等候線理論，在預設服務水準的前提下，推導出如何設置共用元件存貨水準，並提供近似公式估算共用元件平均存貨、顧客在系統中平均等待時間與供應鏈總成本。經由模擬驗證近似公式之準確性，再根據數學模式探討延遲差異化程度與其他系統變數例如第一階段生產線平衡程度、工作站數與服務時間變異等如何影響共用元件存貨水準、共用元件平均存貨與顧客平均等待時間，例如我們發現增加延遲差異化程度能縮短顧客平均等待時間，卻會增加共用元件存貨水準。最後並舉三個例子說明管理者如何運用我們的研究結果來管理延遲差異化系統。

關鍵字

延遲差異化 ； 共用元件 ； 存貨管理 ； 等候線理論

並列摘要

Due to globalization, the competitions among companies are keener and keener. To satisfy diverse needs from customers all over the world, companies have to face the challenge of product proliferation. Therefore, how to satisfy customer’s need for customization at a reasonable cost and in a short period of time becomes an important research topic. Delayed differentiation is one of the effective ways to cope with the challenge of product proliferation. In this dissertation, we combine make-to-stock and make-to-order strategy to design a production system for delayed differentiation. In the first stage of the system, the common component is made-to-stock by an assembly line. In the second stage, the final customization is made-to-order in a job shop environment. In this research, given the service level, we use queueing theory to determine the inventory level of common component and to derive approximations of average inventory, average customer waiting time, and average total supply chain cost. Simulation is used to validate the accuracy of the approximations. Based on the mathematic models, we discuss how the degree of delayed differentiation and other system parameters such as balance of first stage workstation, number of workstations, and variation of service time impact the inventory level of common component, average inventory, and average customer waiting time. For example, we find that increasing degree of delayed differentiation will reduce average customer waiting time but increase inventory holding cost. Lastly, we use three examples to explain how to use the results of this dissertation to manage production system for delayed differentiation.

並列關鍵字

Delayed Differentiation ； Common Component ； Inventory management ； Queueing Theory

參考文獻

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