最低总订货量合约形成机理与联合库存动态定价

This project studies a minimum total commitment (MTC) contract embedded in a finite-horizon periodic-review inventory system. Under this contract, the buyer commits to purchase a minimum quantity of a single product from the supplier over the entire planning horizon. We consider non-stationary demand and per-unit cost, discount factor, and nonzero setup cost. Because the methods used in existing literature are unable to handle our setting, we develop a new method based on a state transformation technique using unsold commitment instead of unbought commitment as state variable. We first show that when setup cost is zero, the optimal ordering policy is a dual base-stock policy, as in the literature, but our proof is simpler and more intuitive. We then extend our method to prove a new result, that the optimal solution for nonzero setup cost is a modied (s; S) policy. We also extends the model to a minimum total business volume commitment over the planning horizon for multiple products that specifies, i.e., the total purchasing dollar amount over the contract duration must be at least the specified volume.  We establish an optimal replenishment policy that minimizes the total inventory cost for the extended model as well. We also extend the basic model to dynamic pricing case with or without setup costs. We use multimodular property to examin the optimal strategies. We further propose two heuristic policies, which numerical tests show to perform very well. We also discuss two extensions to show the generality of our method’s effectiveness. Finally, we use our results to examine the effect of different contract terms such as duration, lead time and commitment on buyer’s cost. We also compare total supply chain profits under periodic commitment, minimum total commitment and no commitment.

由订货价格和多周期承诺量构成的最低总订货量合约广泛应用于实际，既保证供应商稳定性又提供销售商灵活性。本项目研究最低总订货量合约的形成机理和联合库存定价决策。将合约时的联合库存定价决策问题描述成随机动态决策过程，建立多状态联合决策随机动态规划模型，由此探讨联合库存定价的特征及模型参数的关系，最后讨论合约形成机理。具体地，分别对单产品和多产品最低总订货量合约，制定订货策略、联合库存定价策略，给出这些策略表示的分析特征及启发式求解算法；研究最低总订货量合约中联合库存定价策略特征以及与各种模型参数的关系，特别是承诺量对订货策略和动态定价策略的影响；探讨最低总订货量合约对供应商和零售商的适应条件，分析最低总订货量合约的形成机理，对内比较其合约期限，成本对供需双方影响；对外比较其与数量折扣合约，弹性数量合约以及最低订货量合约对供应商和零售商策略与利润的影响。成果为制定合约和联合库存定价提供定量分析。

本项目组成员按照预定研究计划，在顶层设计及团队分工的框架下，全面推进项目的研究工作，取得了一系列研究进展，发表了高水平的研究论文，另有一批高水平研究工作正在整理或评审中，有望逐渐形成一些重要的理论成果。通过本课题的研究，深入刻画了最低总订货量合约模型，并找出单产品与多产品时最低总订货量合约的签订条件；揭示不稳定成本、固定成本、多产品以及提前期存在的零售商最优订货决策；构建了采用最低总订货量合约下最优动态定价决策模型体系，提出了零售商最优动态定价策略，揭示了最优动态策略相对于固定定价策略对零售商的价值；最后在考虑其他基于数量订货时合约的条件下，比较最低总订货量合约与其他合约的关系，得出了最低总订货量合约的适用条件。具体的考虑一类特殊的最低总订货量合约--碳交易相关的固定和可变交易成本并建立动态控制模型，并找到最优控制策略。论证了（s，S）型碳排放权购买政策的最优性。对于可以同时买卖碳排放权限的情况，我们发现以三间隔方式进行交易是最佳的。最后找到了一种非常有效的基于交易和生产活动分离的启发式方法。本文在方法上做出了有影响力的独创性突破，该方法可以应用到类似的商业环境中去。依据上述结果的论文发表在UTD24著名期刊 POM 上。研究了单周期的订货量合同下，买者非法退回所购商品情形下的最优库存动态定价策略。共享经济下客户的时装购买与租赁行为之间的关系，提出了降低非法租赁行为的策略，发现了时装供应链整合在共享经济条件下的重要性。依据上述结果的论文发表在IJPE 上。最后形成一篇工作论文研究了最低总订货量合约（MTC）中的联合库存定价决策。我们从而显示最优订购策略是未售出的承诺依赖政策。我们研究了最有订购策略状态依赖的（s，S）策略。并且在此基础了进行了了两个扩展，以显示我们有效方法具有一般性。项目联合培养硕士3名，海外交流与合作均按照计划执行。