考慮生產線實際需求及空間限制情況下之整合性存貨模式研究

A Study of Integrated Inventory Model under Conditions of Real Production Demand and Space Limit

及時化生產系統的管理模式能有效地運用企業供應鍊內的各項資源，透過生產的計劃和控制，以及庫存的管理，降低生產管理的成本。當企業執行及時化管理，存貨能夠減至最低，甚至“零”的程度。及時化採購的目標亦即為“零庫存”，其方法與準則是買方需要原物料或半成品生產時，賣方以正確的數量，在最短的時間，派送至買方所指定的生產線；賣方不需要生產過多的產品，買方亦無多餘的原物料被採購入庫，所有週轉存貨皆在生產線上，因此存貨可降至最低，進而達到“零庫存”。執行及時化採購可減少買賣雙方生產過程中所可能產生的一切資源浪費，對於提高企業經濟效益有極顯著的效果。本研究建構在及時化採購的方式下，考慮單項產品、單一買方與單一賣方的系統，在“零庫存”條件限制的情形之下，買方與賣方依長期採購合約密切合作，約定賣方依少量、多次地派送高品質的產品至買方。透過整合性存貨模式，尋求在不同派送方式下的賣方最適生產批量與買方最適採購批量。本研究並針對每一模式建立演算法，再利用數值範例加以分析與驗證。

The management model of JIT (Just In Time) production systems can effectively utilize all resources within supply chain, through production planning and control, as well as inventory management to reduce the costs of production management. While enterprise applies JIT management, the inventory will be reduced to the minimum, or even 'zero' level. Thus, the final goal of JIT management is to pursue a non-stock mode of production, namely 'Zero inventory management', in which the JIT Purchasing is required. Its methods and criteria are when a buyer needs raw materials or semi-finished production, the seller sends to the designated production line in correct quantity, in the shortest possible time as buyer requires. Sellers do not need to produce excessive products, nor the buyer have to purchase the excess raw materials for storage, all the stocks will be worked on the production line, so the inventory can be reduced to a minimum, nearly to achieve 'Zero inventory'. To implement JIT purchasing can reduce all possible waste of resources in the production process between buyer and seller that have a significant effect for improving the economic efficiency of enterprises. This study was based on a JIT Purchasing system, which considers individual products with a single buyer and a single seller. Under conditions of the 'Zero inventory' limited circumstances, the buyer and the seller closely cooperate in accordance with long-term purchase contracts, that agrees to frequently transport the high-quality and low-quantity products by small lot size from seller to buyer. Further through integrated inventory model, seeking for the best production quantity of the seller and the best purchasing quantity of the buyer under different transportation ways are carried out. In this study, the algorism was built for each model and the analyses were carried out by numerical examples.