利用模擬方法尋找麵包工廠之最佳再訂購點

Finding optimal reorder points for a bakery factory via simulations

古繼樂(Carlos Koo)

指導教授 ： 謝淑華

國立臺灣大學/工學院/工業工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.02565

摘要

在烘焙業，物料採購是一個影響生產成本的重要關鍵。對於物料採購，其再訂貨點是決定批貨過程成本的變因。因此，尋找最佳再訂貨點可以說是達到物料批貨最低成本的關鍵。然而，市場的需求變化、物料採購的批量大小、生產規模等等都可能改變最佳再訂貨點，如此造成如何選擇再訂貨點變得複雜。許多已經發展的理論方法已經被用於在不同的工業，但卻不適用於烘焙業。
本研究主要目的為利用模擬方法尋找麵包工廠之最佳再訂購點。 利用eM-Plant軟體，一個麵包工廠批貨模擬模式將在本研究中被建立，且被用來模擬不同方案之批貨過程，進而估算批貨成本。本研究的批貨成本包括五種成本，運輸成本、人工搬運成本、缺貨成本、物料時效成本、和大宗採購折扣。三種因子，市場的需求變化、物料採購的批量大小、生產規模大小，搭配不同的因子水準，作為模擬的輸入條件，模擬不同的場景，藉此研究最佳再訂購點對因子水準變化的敏感度。
模擬結果說明：1.當市場變化大時，最佳再訂購點會提高。 2.採用最佳再訂購點，配合適當的採購批量，批貨單位成本有顯著的降低 。 3. 提高產能對於批貨單位成本有相當的助益。

關鍵字

再訂購點 ； 敏感度研究 ； 模擬 ； 麵包工廠 ； 物資採購

並列摘要

The material procurement cost is essential that affects the production cost in the bakery industry. In material procurement process, the reorder point of materials determines the procurement cost. Hence, finding an optimal reorder point of a bakery factory is the key to reach the minimum material procurement cost. However, some of the factors such as market demand variations, material purchase quantity scale, or production scale, may change the optimal reorder point. Many methods have been developed and applied to many different industries, but those methods are not suitable for a bakery industry.
This study intends to find an optimal reorder point for a bakery factory via simulations. A bakery simulation model with eM-plant software is built to study the material procurement process. The procurement cost in this study is composed of five costs: transportation cost, labor cost, stock out cost, material stale cost, and large amount discount. Three factors are used to generate the simulations input, which are: market demand variations, material purchase quantity scale, and production quantity scale. Simulations for the material procurement process of a bakery factory are performed with different levels of factors to approach the near optimal reorder point.
The simulation results reveal: 1.The level of an optimal reorder point will be increased when the degree of the market demand variation is increased. 2. The material procurement cost can be reduced with an optimal reorder points accompanied by a suitable level of a material purchase order quantity, and 3. It can reach the minimum procurement cost if the production scale is enlarged.

並列關鍵字

reorder point ； sensitivity analysis ； simulation ； material procurement

參考文獻

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