代工製造商在長運輸前置時間下需求分析與最佳補貨策略之研究

A Study on OEM demand analysis and optimal replenishment policy under long lead time constraint

蔡仲柏(Zhong-Bo Tsai)

指導教授 ： 姚銘忠

國立交通大學/管理學院/運輸與物流管理學系/碩士(2018年)

摘要

跨國/跨洋運輸所需要的長前置時間，常使全球供應鏈中的供應商在需求預測與出貨決策時面臨困難。在長運輸前置時間的條件下，針對客戶端採取供應商管理存貨以最低存貨水準作為服務評估指標，本研究提出整合需求預測與出貨的決策支援機制。本研究針對此問題分為三個部分進行研究：1) 針對客戶端所使用的評估機制，協助供應商端與客戶端客觀設置最低存貨水準的計算程序；2) 提出系統性方法，協助分析客戶端之需求；3) 在長運輸前置時間前提下，提出決策之啟發式演算法與配套機制，協助供應商在常態與尖峰需求下之補貨決策，以滿足最低存貨水準及提升客戶對供應能力之評分。本論文以I公司作為案例，其對於J客戶的補貨需5週的長運輸時間。運用本研究所提出的整合性需求預測與出貨決策機制及4種品項的歷史資料進行模擬分析。原先4種品項的成功補貨比例接未超過16%。但本研究的結果顯示在運用本研究所提出的方法之後，4種品項皆可達到超過90%的成功補貨比例。顯示本研究所提出之整合性方法，可作為I公司優質的決策輔助工具。

關鍵字

供應商管理存貨 ； 最低存貨水準 ； 需求分析 ； 補貨 ； 啟發式演算法

並列摘要

A long lead time usually required in across boarder/ocean transportation often makes the suppliers’ decision-makings in forecasting and replenishment more difficult. Under the condition of long transportation lead time, this study proposes a decision-support mechanism integrating demand forecasting and replenishment decisions to meet the minimum stock-level as the service-evaluation index designated by the customer. We divide the decision-support mechanism into three parts: 1) Propose a procedure that assists the supplier and the customer to objectively set the minimum stock-level following the customer’s evaluation mechanism; 2) Suggest a systematic approach for the analysis of customer’s demand; 3) Under the condition of long transportation lead time, propose heuristics and supporting mechanisms that help the supplier in the determination of replenishment policies facing regular and peak demand to meet the minimum stock-level and improve its evaluation of supply capability. This study employs Company I as our case study in which the replenishment of Customer J requires a long lead time of 5 weeks. Originally, the successful replenishment rates of those 4 items were no more than 16%. Following the results of our simulation analysis, the successful replenishment rates of those 4 items reach more than 90% after applying the proposed mechanism. Therefore, our integrated mechanism shall serve as valuable decision support tool for Company I.

並列關鍵字

vendor managed inventory ； VMI ； minimum stock level ； demand analysis ； replenishment heuristic

參考文獻

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