Approximate analysis and optimization of batch ordering policies in capacitated supply chains

Devising manufacturing/distribution strategies for supply chains and determining their parameter values have been challenging problems. Linking production management to stock keeping processes improves the planning of the supply chain activities, including material management, culminating in improved customer service levels. In this study, we investigate a multi-echelon supply chain consisting of a supplier, a plant, a distribution center and a retailer. Material flow between stages is driven by reorder point/order quantity inventory control policies. We develop a model to analyze supply chain behavior using some key performance metrics such as the time averages of inventory and backorder levels, as well as customer service levels at each echelon. The model is validated against simulation, yielding good agreement of robust performance metrics. The metrics are then used within an optimization framework to design the supply chain so as to minimize expected total system costs. The outcome of the optimization framework specifies how to move inventory throughout the supply chain and how to set inventory control parameters, i.e., reorder levels and replenishment batch sizes.

为供应链设计制造/配送策略并确定其参数值一直是具有挑战性的问题。将生产管理与库存保管流程相联系可改善供应链活动的规划，包括物料管理，最终提高客户服务水平。在本研究中，我们考察一个由供应商、工厂、配送中心和零售商组成的多级供应链。各阶段之间的物料流动由再订购点/订购量库存控制策略驱动。我们开发了一个模型，利用一些关键性能指标（如库存和缺货水平的时间平均值以及各级的客户服务水平）来分析供应链行为。该模型通过模拟进行了验证，在稳健性能指标方面取得了良好的一致性。然后，这些指标在一个优化框架内被用于设计供应链，以使预期的系统总成本最小化。优化框架的结果明确了如何在整个供应链中移动库存以及如何设置库存控制参数，即再订购水平和补货批量大小。