可变提前期的易逝品供应链协调

易逝品供应链作为供应链的一个重要分支日益受到关注,已成为现代商业活动中不可或缺的组成部分.在提前期与预测误差呈线性关系,提前期与赶工成本呈分段线性关系的前提下,建立了在分散决策、集中决策两种模式下可变提前期的易逝品供应链库存模型,设计了优化算法并通过数值分析比较了这两种模式下供应链整体及其成员收益的变化.进一步探讨了在合作的分散决策模式下,可变提前期的易逝品供应链实现渠道协调的可行性以及实现渠道协调的条件,并通过数值例子说明了模型的结论.     

基于瓶颈供应商提前期的供应链协同契约研究

针对瓶颈供应商对制造商采购提前期制约的影响,在一个"两供应商--单制造商"组成的两阶供应链系统中,构建了分散决策契约模型和集中决策下的协同契约模型,通过比较供应链的总体收益,指出核心制造商从供应链的角度提高瓶颈供应商在提前期上协同的重要性并做了详细分析,并从提高供应商协同积极性的角度提出了对供应链渠道收益分配机制。最后,通过数值分析证明了文章中提出的新观点。     

供应链中供需双方合作批量模型的研究

提出供需研究是供应链管理的最重要、最基本的内容;分析了非合作博弈下,供需双方独自确定其最佳批量可能产生的不良后果;建立了供应商在订货商已作决策的条件下的最优生产批量模型.最后研究了供需双方合作博弈下的价格折扣模型,从而使供应链得到优化,供需双方达到双赢的目的.     

含服务水平约束的可控提前期供应链Staekelberg模型与协调机制研究

为了有效地缩短订货提前期与降低库存成本,首先从Stackelberg主从对策角度建立了含服务水平约束的可控提前期供应链库存优化模型,提出了该模型的求解算法;然后从集中决策角度建立了另一类含服务水平约束的可控提前期供应链库存优化模型,并提出该模型的求解算法。利用数值分析对两类模型的优化效果进行比较,结果表明:集中决策模式下的优化效果明显优于Stackelberg主从对策模式下的优化效果,但在缺乏合理的激励机制情形下,供应链各参与方未必有足够积极性接受集中决策模式。为此,提出一种库存费用分担机制来激励供应链各参与方接受集中决策模式。     

供应链提前期供需联合优化库存模型研究

本文研究由生产商和客户组成的二级供应链库存联合优化问题, 假设提前期服从均匀分布, 提前期订货受生产商的生产行为和客户的订货行为的制约, 建立了以库存成本为目标函数的供应链提前期供需库存模型, 提出了联合优化解决方案, 证明了目标函数在最优订货量和最优订货次数处存在最小目标值。在此基础上, 分析了提前期对供应链库存联合优化决策的影响。数据分析表明, 联合优化决策方法的库存成本曲线始终在分散决策优化方法的成本曲线的下方, 因此联合决策方法是非常有效的。     

基于Bayes需求预测更新的供应链合作策略研究

在预测误差与提前期成对数线性关系,赶工成本与提前期成分段线性关系条件下,研究了基于Bayes需求预测更新的易逝品供应链合作策略问题.通过建立零售商独立决策的优化模型,讨论了模型最优解的存在性,论证了供应链合作的必要性.进一步提出了三参数的供应链风险分担契约来协调分散决策的供应链,分析了实现供应链渠道协调的条件.并通过数值分析和参数的灵敏度分析说明了上述结论以及算法.分析结果表明,这种供应链契约不仅能够实现供应链利润最大化,而且能够通过契约参数的调整,按照供应链成员增值能力的大小灵活划分供应链成员之间的利润分配比例.     

信息不对称条件下可控提前期供应链协调机制研究

探讨了信息不对称条件下提前期可以通过额外的赶工成本来加以控制的两级供应链协调问题。分别建立了分散决策和集中决策情形下的可控提前期供应链库存优化模型,并在充分考虑各参与方个体理性的基础上,探讨了分销商库存信息不对称情形下的供应链协调机制。最后通过数值分析证明该协调机制既能诱使分销商申报真实的库存持有成本信息,又能够在供应链合作双方成本均有改进的基础上,达到供应链系统的最优。     

不确定环境下的Supply-hub协同补货决策

个性化需求与零部件创新使得产品需求和补货提前期不确定,对供应链补货决策和运行成本产生重要影响。将提前期不确定因素引入Supply-hub协同补货研究中,探讨提前期随机和需求不确定情况下,考虑零部件配套性的三供应商单制造商生产两定制产品的Supply-hub协同补货决策问题;提出了三种补货策略,以供应链运行成本最小化为目标,建立不同策略下的供应链补货模型并求解最优补货批量和供应链最小运行成本;发现三种补货策略均存在唯一最优补货批量,基于Supply-hub的两种协同补货策略和基于分散决策的供应商独立补货策略各有优势,但基于Supply-hub的批量及时间协同的补货策略恒优于基于Supply-hub的集中补货策略。最后,通过MATLAB进行算例分析验证结论,发现基于Supply-hub的批量及时间协同的补货策略能有效降低需求不确定性带来的成本增加风险;通用件的提前期波动对于供应链期望运行成本的影响要高于定制件提前期波动的影响,因此在进行供应链补货策略选择时更加关注通用件提前期。     

考虑可控提前期和缺货损失的供应链费用分担策略研究

假定在一个由一个供应商与一个零售商组成的供应链中,供应商向零售商提供单一产品且其补货提前期可以通过增加费用进行压缩,零售商的外部需求不确定和部分缺货可以补充,本文建立了供应链分散决策和集中情形下的库存模型,得出了包含最优提前期、订货批量、安全库存因子和生产批量等决策变量的最优解,并提出了买卖双方分担压缩提前期投入费用的策略。算例分析表明,单项费用分担策略虽然能够使提前期压缩到与供应链集中决策时的情形一致,并实现供应链帕累托优化,但无法实现供应链整体最优化。     

时间价格敏感型需求下的二阶段供应链协调模型

本文讨论时间价格敏感型需求环境下,两阶段供应链中供应商和零售商的最优决策,其中供应商的决策为供应提前期和批发价格,零售商的决策为零售价格.通过分析集中决策模式和分散决策模式下的决策过程,进行优化求解给出了两种模式下最优决策的数学表达式;并设计了实现供应链完美协调的组合契约.     

Centralized versus Decentralized Competition for Price and Lead‐Time Sensitive Demand

We study two firms that compete on price and lead‐time decisions in a common market. We explore the impact of decentralizing these decisions, as made by the marketing and production departments, respectively, with either marketing or production as the leader. We compare scenarios in which none, one, or both of the firms are decentralized to see whether decentralization can be the equilibrium strategy. We find that under intense price competition, with intensity characterized by the underlying parameters of market demand, firms may suffer from a decentralized structure, particularly under high flexibility induced by high capacity, where revenue‐based sales incentives motivate sales/marketing to make aggressive price cuts that often erode profit margins. In contrast, under intense lead‐time competition, a decentralized strategy with marketing as the leader can not only result in significantly higher profits, but also be the equilibrium strategy. Moreover, decentralization may no longer lead to lower prices or longer lead‐times if the production department chooses capacity along with lead‐time.      

零售商竞争环境下分散式供应链的定价与交货期联合决策模型

考虑了由一个制造商和两个相互竞争的零售商组成的两阶段分散式供应链系统,建立了价格和时间双敏感需求下的供应链定价与交货期联合决策模型,并给出了基于Stackelberg博弈的供应链定价和承诺交货期的最优决策。随后,以集中式供应链的决策为基准,分析了分散式供应链决策的效率。最后,通过数值分析,研究了市场因素和营销渠道竞争因素对分散式供应链的决策效率及承诺交货期的影响。结果表明,供应链下游的渠道竞争有利于提高分散式供应链的决策效率和缩短承诺交货期,从而提高整个供应链的市场竞争力。     

引入自有产品对零售商主导的供应链成员决策的影响

随着零售市场竞争的日益激烈,越来越多的零售商采用自有产品营销战略。在零售商处于主导地位的供应链中,本文首先假设消费者对品牌产品的估值服从均匀分布,分别在一体化、分散式和协调式供应链系统下给出了零售商引入自有产品的条件,分析了其对双方决策和利润的影响。随后,本文假设消费者对品牌产品的估值服从正态分布,通过算例分析了引入自有产品对双方决策和利润的影响。研究表明,零售商提供自有产品作为一种策略,迫使制造商降低品牌产品的批发价格,削弱因双方独立决策而导致的“双重边际效应”,使得他在分散式供应链和协调式供应链中都能获利,但对制造商总是不利。在正态分布的情形下,引入自有产品在分散式供应链中对制造商有利,但在协调式供应链系统中,对制造商不利。     

DECENTRALIZED MULTIECHELON INVENTORY CONTROL

This paper considers a model for decentralized control of an inventory system consisting of 1 central warehouse and a number of retailers. The cost structure includes holding costs at both echelons and shortage costs proportional to the time until delivery at the retailers. We analyze a procedure for coordinated but still decentralized control of the system. The procedure is based on a simple approximation, in which the stochastic lead times perceived by the retailers are replaced by their correct averages. The approximation enables us to decompose the considered multiechelon inventory problem into a number of single echelon problems, 1 for each installation. The information about how a certain decision at the warehouse affects the retailers is conveyed through the marginal cost increase with respect to a change of the expected lead time. This information about the retailer costs is used as a shortage cost at the warehouse. We show that a coordination procedure based on this information can be used for finding near-optimal reorder points for the system and provide bounds for the approximation errors.     

Vertical Integration with Price‐Setting Competitive Newsvendors*

This article addresses the problem of distribution channel design under demand uncertainty. We consider two manufacturers, each producing a substitutable product and selling it through either a decentralized or an integrated retail store, which is modeled as a price‐setting newsvendor. A multiplicative demand function incorporating a random shock term is assumed. Of primary interest is how demand uncertainty and production cost affect the equilibrium distribution channel structure. Results indicate the following: On the one hand, if the random shock term is uniformly distributed on [0, x], then the equilibrium design does not depend on the variance of the shock. On the other hand, if the random shock term is uniformly distributed on [1 −r, 1 +r], then the equilibrium design does depend on the variance of the shock. In particular, an increase in r favors the integrated structure where both channels are integrated and hurts the decentralized configuration where both channels are decentralized. Additionally, we explain the qualitative similarities and differences between the structural properties of the equilibrium distribution channel structure when demand is, and is not, uncertain. We also establish that production cost always favors the decentralized structure, while it hurts the integrated one. One important managerial implication of our study is that, by reducing the number of decisions made in supply chains, the impact of demand uncertainty can be controlled to a certain extent.     

A numerical analysis of supply chain performance under split decision rights

We examine periodic review supply chain models where order quantity and shipping frequency are both decision variables and decision-making rights are split between supply chain agents. We address two general questions: (1) when does decentralized decision making result in the greatest loss in supply chain performance; and (2) what effect does the distribution of channel power have on performance loss. We characterize optimal policies where possible in each scenario and we use numerical analysis to generate insights. We find that performance losses from decentralized control are somewhat limited in our results due to risk pooling and that the magnitude of performance loss is strongly influenced by the relative holding and penalty costs, but somewhat invariant to demand uncertainty. Furthermore, we find that concentrating channel power with the supplier can lead to supply chain profits that are very close to a centralized scenario, but also results in lower customer service levels.     

考虑随机需求与收入共享的风险规避型V2G备用决策模型

在CVaR风险度量准则下,构建了考虑随机需求与收入共享的风险规避型V2G备用决策模型,推导了集中和分散两种决策下渠道成员最优决策行为的解析解,并进一步比较分析了随机需求变量服从均匀分布时的均衡策略。研究发现,集中决策下的最优V2G备用预留因子与渠道整体的风险规避度正相关,而均衡时的V2G备用销售价格与渠道整体的风险规避度的相关性不确定,且受到随机需求变量的分布函数影响;分散决策下的最优V2G备用预留因子仅与电网公司的风险规避度有关,而均衡时的V2G备用销售价格受到电网公司的风险规避度、购电价格以及电动汽车用户收入共享系数等的共同影响;电动汽车用户的最优V2G备用收入共享系数与其风险规避度正相关,而与电网公司的风险规避度负相关。数值仿真结果表明,在绝大多数情形下收入共享合约并不能完美协调此类V2G备用渠道的分散决策行为。