中文摘要：

企业可以在整个计划时期内任意时刻订货,离销售季节开始时刻越近,市场需求的预测值越准确,但提前期较短时单位采购成本会较高。因此企业需要在更准确的市场需求预测和采购成本之间进行权衡。当市场需求预测值的调整量为任意给定连续分布时,证明企业最优库存策略为basestock策略,该策略必定存在且唯一,建立最优库存策略的求解算法。通过分析参数变化对最优库存策略的影响,说明企业如何在市场需求预测和采购成本之间进行权衡。数值算例表明在预测更新过程条件下,最优库存策略与经典报童模型有较大的差异,且可以显著降低总成本。

英文摘要：

Firms can order at any time in planning horizon.When it is nearer to the beginning of the sales season,the demand forecast is more precise,but the lead time is shorter and procurement unit cost is higher.Thus,firms must consider the trade off between demand forecast precision and procurement unit cost.We prove the optimal policy is base stock policy when the demand forecast evolution distribution is general and continuous distribution,and develop solution algorithm.Numerical examples are given and the results show the optimal inventory policy is clearly different from traditional classic news-vendor model when demand forecast evolution is considered.Significant savings are achieved when forecast evolution process.