在固定生產週期內考慮銷售損失及服務水準之存貨策略

Inventory Strategy For Finite Planning Horizon Considering Lost Sales and Service Level

馬光寧(Gunawan Mangkuharjo)

指導教授 ： 黃惠民

中原大學/電機資訊學院/工業與系統工程研究所/碩士(2014年)

https://doi.org/10.6840/cycu201400254

摘要

當缺貨發生時，顧客需求可能會永遠失去。銷售損失的狀況通常發生在完全競爭的市場。缺貨也會造成配銷商與零售商的商譽喪失。針對短生命周期的商品，有限期間的經濟存貨模式會比無限期間的生產規劃模式要來的適當。
本研究延伸以前的傳統經濟訂購量（EOQ）存貨模式，在考量銷售損失及有限的生產規劃期間下，發展一個精確的演算法來求解。以總相關存貨成本(包含訂購成本、持有成本及短缺成本)之極小化為目標，決定最佳之訂購次數與再訂購點。數值範例和敏感度分析驗證本研究所提出模型的正確性及實際運用。分析結果顯示本研究演算法所得到之解略高於非線性整數規劃法所求出之全域最佳解。本研究結果可以提供決策者在存貨系統規劃初期，決定考慮服務水準下之最佳存貨策略。

關鍵字

服務水準 ； 存貨 ； 有限規劃期間 ； 銷售損失

並列摘要

In a perfectly competitive market, lost sale happens when there is a shortage; demand is ususally lost permanently. Shortages also result in a lost of goodwill for the distributor or retailer. The finite-horizon economic inventory model is more appropriate than the infinite-horizon planning model for product with short life cycles.
This study extends a previous Economic Order Quantity (EOQ) model to include lost sales inventory and finite planning horizon. Exact algorithms are developed for this model. The objectives are to determine an optimal number of orders and reorder point to minimize total relevant cost that consists of order cost, holding cost, and shortages cost. Numerical examples and sensitivity analyses are performed to validate the models and to demonstrate the practical use of the study. The analysis shows that the minimum total relevant cost of the finite planning horizon method using the proposed algorithm in this study is higher than the global optimal solution using integer non-linear programming. Managerial insights are provided for decision makers to implement the optimal inventory policies with service levels that have been determined at the beginning of the inventory system plan.

並列關鍵字

Lost Sales ； Service Level ； Inventory ； Finite Planning Horizon

參考文獻

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