應用拔靴法於電腦維修零件最適安全存量之研究

A Study of Bootstrapping Method for the Optimal Safety Stock in Computer Spare Parts

林怡馨(I-Hsin Lin)

指導教授 ： 顏憶茹

國立臺中科技大學/管理學群/流通管理系碩士班/碩士(2011年)

https://doi.org/10.6826/NUTC.2011.00021

摘要

科技的進步，電子產品更新與汰換的速度也隨之攀升，企業應該要持有一定數量的維修零件，以供售後服務所需，除了預期存貨外，還必須要持有安全存量。由於維修零件又屬於間歇性的不規則需求型態，更增加了需求上的不確定性。
本研究以國內某知名電腦公司所提供的桌上型電腦零件歷史資料，運用拔靴法來建立安全存量模式，並追求低缺貨率與高達交率為目的，透過ABC分析進行品項分類後，從各類中挑選六種品項作為計算安全存量之依據，並以服務水準、缺貨率、達交率、總成本分析作為績效評估的指標，最後依照服務水準來擬定各零件之安全存量。
實證結果顯示，拔靴法的結果比移動平均法可達到更高的服務水準與達交率，本研究依照各類不同的服務水準制定安全存量，為企業擬出依據實際情況與服務策略的不同，可自行調整安全存量，其中A類零件因為使用頻次多且需求量較大，因此安全存量較大；B類與C類零件因需求間隔時間長、需求量偏低，因此安全存量較A類小。

關鍵字

拔靴法 ； 安全存量 ； 維修零件

並列摘要

The advance of technology has speeded up the updates and replacements of electronic products. Companies should hold a certain amount of spare parts for after-sales service. In addition to the anticipation inventories, companies also must hold safety stock. However, as spare parts have an intermittent demand pattern, there is great uncertainty inherent in estimating the safety stock.
In this study, a renowned computer company provided the historical information of its desktop computer parts. We use bootstrapping method to establish a safety stock model, with an aim to reach the goal of low stock out rate and high fill rate. We adopt ABC analysis to classify all items and choose six stock keeping units (SKU) from a variety of selected items as the basis for safety stock. We use service level, stock out rate, fill rate, and total cost analysis as the performance evaluation indicators. Finally, we establish the safety stock for various spare parts based on the service level.
The empirical results show that bootstrapping method can achieve better service and higher fill rate than moving average method. We establish the safety stock for different types of service level, so that companies can adjust the safety stock as per the actual situation and their service strategies. Because the class A parts are used more frequently and with a higher demand, they have a larger safety stock. The class B and class C parts have a long interval between usages and low demand, so their safety stock is smaller than the class A parts.

並列關鍵字

Bootstrapping Method ； Safety Stock ； Spare Parts

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