多级分销网络的延迟订购策略分析

延迟订购策略本质上是从时间维度出发，在维持总成本不变的条件下，推迟订购时间，降低库存水平．首先给出了多级分销网络结构的形式化描述，其次通过分析立即订购和延迟订购的边际条件，确定订购最佳时间，并给出了在最佳时间订购时，库存总成本最小的证明．最后，为了便于实施将订购风险适当简化，推导了近似计算公式．从理论上，在多级分销网络中，采用延迟订购策略可以降低库存水平和降低库存成本．

Analysis of delaying order policy in multi-echelon distribution network

A delayed ordering strategy essentially aims at lowering the stock level by delaying the ordering time while the total inventory cost kepts unchanged. Firstly, a formal topology representation of a multi_layer distribution network is suggested. Then, the optimal ordering time is deduced after both the marginal conditions of immediate ordering and delayed ordering have been analyzed. It is also proved that the inventory cost will be minimum if ordering occurs at the optimal time. Finally, a practical approximate formulation for calculating the optimal ordering time is given where ordering risks are properly simplified. Therefore in theory, the delayed ordering strategy can reduce not only the stock level but also the inventory cost.