供应商管理库存应对突发事件

本文研究短生命周期供应链,它由一个生产商和一个销售商组成,供应商替销售商管理库存。首先指出供应商管理库存同样存在激励冲突,出现双边际效应,即分权决策下供应商的存货量小于供应链利润最大的库存量。接下来,提出一个使供应链达到合作的合约--未售货物补偿合约,即,销售商要对没有售完的货物进行补偿。该合约具有参数简单,管理费用低,且能将供应链利润在供应商和销售商之间任意分配。然后研究当突发事件导致供应商的生产费用(包括采购费用,运输费用等)发生变化对供应链的影响。最后,提出一个能应对突发事件并使供应链达到合作的合约。利用数值例子说明合约的价值。     

一个VMI环境下的协调合约及其抗突发事件性

本文通过在销售商主导的合约制定中引入惩罚函数,为不确定需求环境下供应商管理库存(VMI)提出一个新的合作合约,使供应商的存货量符合供应链利润最大的要求。该合约具有参数简单,管理费用低,并能将供应链的利润在供应商和销售商之间任意分配等优点。然后研究了该合约抗突发事件的能力,证明了如果突发事件导致供应商的生产费用变化,原合约仍然使供应链合作,合约具有一定的鲁棒性。若突发事件导致需求变化,则要对原来的合约作相应的修改。修改后的合约具有抗突发事件性。     

需求具有价格敏感性的供应链的利益共享合约

利益共享合约是促使供应链协作的一种重要手段。本文建立了具有价格敏感性的最终消费需求的利益共享合约模型。在考虑最终销售价格为内生变量的条件下,借助于报童模型,分别分析在此合约下销售商和供应商的决策行为,并给出销售商的最优决策的计算公式以及该合约参数Φ的取值范围。最后给出实例分析,验证在利益共享合约下的供应链能达到协作状态。     

销售商的努力影响需求变化的供应链的合约

本文首先重新考察报童模型,认识设计使供应链达到合作的合约的内在机制。在此基础上,提出一个设计供应链合约的一般模型,然后利用此模型分析在销售商的努力影响需求变化的情形下使供应链达到合作的合约的设计框架,同时提出一个在销售商的努力影响需求变化的情形下使供应链达到合作的合约。     

供应链中期权合约与混合合约决策选择

研究由单供应商和单零售商组成的二级供应链，面对不确定的市场需求，零售商可以通过期权合约或混合合约(期权合约与远期合约的组合)向供应商订购产品。通过建立 Stackelberg 博弈模型，求解两种合约形式下零售商的最优采购决策与供应商的最优定价决策。亦从供应商和零售商的不同视角比较了两种合约。结果显示，供应商倾向采用期权合约销售产品，即使在混合合约背景下，供应商也会通过提高远期合约价格来阻止零售商通过远期合约采购产品。而零售商通过期权合约采购时收益能否提升则会受到期权执行价格和产品残值的影响。     

产品召回供应链中线性保险合约与订货决策

考虑一个由单供应商和单制造商组成的二级供应链,在不确定市场需求情形下考虑产品召回,站在制造商角度研究供应链线性保险合约下的最优订货决策以及最优线性保险合约决策。研究表明,最优的订货决策与产品召回概率以及线性保险系数相关,存在唯一的最优订货量来最大化制造商的利润。对于密度函数倒数的导数较大的一般需求分布函数,最优的线性保险系数与线性保险合约的固定费用以及产品召回概率有关。当产品召回概率和线性保险合约的固定费用均较小时或者产品召回概率较大但线性保险合约的固定费用适中时,制造商通过选择线性保险合约可以改善自己的利润。     

供应链库存合约研究

研究了制造商与其供应商的供应链最优库存策略和在非合作情况下的库存策略,比较分析了两种情况下的库存策略,并设计了库存合约;分析表明,制造商通过设计有效的转移支付合约,可以实现供应链库存的最优化。     

基于补偿合约的供应链定价与能力设计的协调问题研究

研究和分析了在需求不确定并且受价格影响的情况下,供应链中制造商与供应商的产品定价与能力设计的协调问题。制造商从供应商处采购用于产品生产的关键零部件,供应链面临的潜在需求服从随机分布,有效需求则受产品定价的影响。当供应商的生产能力出现约束时,制造商可以从外部其他渠道获取关键零部件,但是需要付出一个更高的采购价格。制造商确定产品的销售价格,供应商确定生产能力。分析比较了在集成供应链与独立决策的供应链中的定价与能力计划策略,提出了一种能够有效协调制造商和供应商的决策行为的补偿合约。最后,进行了数值分析,证明补偿合约的有效性。     

合约回收制对闭环供应链影响分析

为了提高再制造闭环供应链的运作效率,文章设计了新的回收方式——合约回收制,并研究了这种回收方式对消费者、企业和整体供应链的影响。在新产品和再造品同时存在的混合市场前提下,文章主要讨论了制造商(M模式)、经销商(R模式)和第三方回收商(3P模式)各自为回收再造主体时,合约回收制对产品定价、回收率、行业规模等因素的影响。研究结果表明:(1)消费者受益于合约回收制;(2)合约回收制壮大了闭环供应链的规模;(3)回收率与再造品评价成正比,与新产品评价成反比,其中R模式和3P模式中回收率因合约回收制而提高;(4)制造商均受益于合约回收制,但经销商和第三方需满足部分条件才可获益。     

考虑销售商风险规避的双边信息不对称的供应链协调

非对称信息和风险态度成为影响供应链协调的重要因素,而契约机制设计是实现协调的一种方法。本文在双边成本信息不对称情形下研究供应链契约机制的设计问题。考虑了由一个风险中性的供应商和一个风险规避的销售商组成的二级供应链,供应商和销售商分别拥有私人的生产成本信息和销售成本信息。在分散决策下,供销双方为获得更好的私人利得从而有隐藏信息的动机。为实现信息的真实揭示,文中引入了利他委托人这一概念,从而供应链成为协调主体。借助AGV机制思想,设计了具有激励性质的转移支付,并且基于均值-方差方法建立了非对称信息下的供应链模型。我们发现销售商风规避度在一定范围时,所设计的激励机制能够实现供销双方信息的真实揭示,但并不能完全保证双方的事后非负收益。为解决这一问题,给出一种以期望信息租金比为基础的事后收益分配规则,设计了补偿参数。结合转移支付和补偿参数,提出了一个契约机制。我们发现当销售商风规避度不超过上界k_r时,该机制能真实的揭示信息,并且能够保证供销双方的事后合理的收益分配。此外,当供销双方真实揭示信息时,风险规避度较大的销售商组成的供应链有更低商品交易量和供应链收益。最后,给出数值算例,验证信息揭示的激励有效性并对风险规避度进行敏感性分析。本文的研究将对双边不对称信息下的供应链管理提供一定的理论基础和实践指导。     

一个考虑回收契约的两级供应链库存决策模型研究

讨论了一个季节性商品销售环境下的两级供应链库存决策模型,在分析传统回收契约模型的基础上,引入了一个特殊的回收契约,讨论不同契约参数下供应链成员的最优决策.研究表明,在该契约下通过合理的契约参数设计,供应链可以实现帕累托改进.用一个算例对结论进行了说明.     

基于报童模型的两级供应链回购契约协调研究

研究具有单一供应商和单一销售商的供应链系统回购契约协调机制。分析了报童模型下两级供应链双边际化效应,建立了基于报童模型的分散式系统、集中式系统的供应商、销售商利润模型,讨论了如何通过回购契约来消除"双边际化效应"。结果表明:回购契约的采用使批发价格比不采用契约时的批发价格低,且使订货量增加,从而使供应链的总利润增加,并且减少了缺货带来的损失,同时更好的满足了顾客需要。最终实现了独立个体最优决策与系统最优决策一致化的供应链协调。     

Channel Coordination with a Risk‐Neutral Supplier and a Downside‐Risk‐Averse Retailer

We investigate how a supply chain involving a risk‐neutral supplier and a downside‐risk‐averse retailer can be coordinated with a supply contract. We show that the standard buy‐back or revenue‐sharing contracts may not coordinate such a channel. Using a definition of coordination of supply chains proposed earlier by the authors, we design a risk‐sharing contract that offers the desired downside protection to the retailer, provides respective reservation profits to the agents, and accomplishes channel coordination.     

Supply Contract Design for Competing Heterogeneous Suppliers under Asymmetric Information

This study considers a supply chain with two heterogeneous suppliers and a common retailer whose type is either low‐volume or high‐volume. The retailer's type is unknown to the suppliers. The flexible supplier has a high variable cost and a low fixed cost, while the efficient supplier has a low variable cost and a high fixed cost. Each supplier offers the retailer a menu of contracts. The retailer chooses the contract that maximizes its expected profit. For this setting, we characterize the equilibrium contract menus offered by the suppliers to the retailer. We find that the equilibrium contract menus depend on which supplier–retailer match can generate the highest supply chain profit and on how much information rent the supplier may need to pay. An important feature of the equilibrium contract menus is that the contract assigned to the more profitable retailer will coordinate the supply chain, while the contract assigned to the less profitable retailer may not. In addition, in some circumstances, the flexible supplier may choose not to serve the high‐volume retailer, in order to avoid excessive information rent.     

Coordination in a Single‐Supplier,Multi‐Retailer Distribution System: Supplier‐Facilitated Transshipments

We consider supplier‐facilitated transshipments for achieving supply chain coordination in a single supplier, multi‐retailer distribution system with non‐cooperative retailers. The previous transshipment literature has focused on coordination through retailer‐negotiated transshipments and thus does not consider the supplier's decision‐making. In contrast, in this study, we assume the supplier is an active participant in the system and we seek to understand how the supplier can facilitate the implementation of coordinating transshipments. We study a two‐period model with wholesale orders at the start of the first period and preventive transshipments performed at the start of the second period. Inspired by a supplier‐facilitated transshipment scheme observed in practice, we assume the supplier implements transshipments through a bi‐directional adjustment contract. Under this contract, each retailer can either buy additional inventory from, or sell back excess inventory to, the supplier. We show that coordination can be achieved through carefully designed contracts with state‐dependent adjustment prices and a wholesale price menu. We demonstrate that the supplier's role in facilitating coordinating transshipments is critical. In addition, we use our understanding of the coordinating contract form to derive some simpler and easier‐to‐implement heuristic contracts. We use a numerical study to demonstrate the value, to the supplier, of using the coordinating adjustment and wholesale prices, and to evaluate the heuristics’ performance.     

公平偏好和销售努力下供应链期权契约协调

考虑公平中性的供应商将报童类商品售给公平偏好的零售商,商品需求随机且受销售努力影响。刻画了期权契约下零售商关于实物和期权商品采购及销售努力的联合策略,设计了协调供应链的期权契约和促销成本分担机制。研究表明：在确保零售商参与供应链下,无论契约参数如何设计,零售商要么仅采购实物商品,要么同时购买实物商品和期权;且仅当设计的契约能诱导零售商购买期权时,供应链的协调才可能实现。探讨了公平偏好对零售商策略和协调契约的影响,结果表明：零售商越偏好公平,实物商品采购量和努力水平越低,但期权购买量依赖于契约参数之间的关系;协调契约可行域随公平偏好程度递减,但始终存在;在协调契约下,零售商的策略选择与公平偏好程度无关。最后实施了数值分析。     

零售货架的线性补贴策略与供应链协调

考虑由一个供应商和一个零售商构成的供应链,供应商提供零售商单一产品,零售阶段的市场需求量随机地依赖于零售商的货架展示量。由于货架空间的稀缺,零售商的成本为非线性的成本函数以符合实际的情况。如果零售商在观察到需求之前决定货架空间,货架补贴可以提高渠道效率;如果零售商在观察需求之后,进行货架决策,补贴降低了供应链效率。由于零售商的努力水平可以验证,供应商可以使用回购加零售货架的线性补贴策略协调供应链,但是需要考虑零售阶段的库存决策与货架分配的决策顺序,而采取完全不同的协调方式。最后通过数值算例说明了所得结论。     

非对称信息下闭环供应链回购契约应对突发事件策略研究

研究了非对称信息下一个制造商和一个零售商组成的两级闭环供应链在回购契约下的协调问题。在考虑零售商销售成本信息为非对称信息和随机性市场需求基础上,首先,分析了在正常状态下分散式系统决策情况,通过重新设计可变参数解决了信息不对称的问题,实现了回购契约下的信息共享和供应链的完美协调;然后,探讨了闭环供应链回购契约应对突发事件的协调问题。研究结果表明：当突发事件造成市场规模和制造商生产成本同时扰动时,闭环供应链的销售活动将受影响,闭环供应链的协调将被打破,而闭环供应链的废旧品回收活动却不受突发事件的影响。为此,给出了闭环供应链回购契约的应急决策。最后通过数值算例验证了结论。     

A delay-in-payment contract for Pareto improvement of a supply chain with stochastic demand

We consider a supply chain consisting of a single supplier and a single retailer with stochastic customer demand, which is operated over an infinite horizon. We propose a delay-in-payment contract to coordinate the supply chain. With this contract, the supplier allows the retailer to pay partial order cost at the ordering epoch, and to pay the remaining portion after a permissible number of periods. The system is formulated as a stochastic dynamic programming problem. It is shown that there exists a base-stock policy to be optimal. Compared with the traditional wholesale-price contract, the delay-in-payment contract with appropriate parameters can achieve a Pareto improvement (i.e., the performances of both the supplier and the retailer using the delay-in-payment contract are better than those using the wholesale-price contract). Numerical studies are performed to investigate both the effectiveness of the Pareto improvement, and the impact of the major parameters of the delay-in-payment contract on the system performance.     

Pay‐Back‐Revenue‐Sharing Contract in Coordinating Supply Chains with Random Yield

We consider coordination issues in supply chains where supplier's production process is subject to random yield losses. For a simple supply chain with a single supplier and retailer facing deterministic demand, a pay back contract which has the retailer paying a discount price for the supplier's excess units can provide the right incentive for the supplier to increase his production size and achieve coordination. Building upon this result, we consider coordination issues for two other supply chains: one with competing retailers, the other with stochastic demand. When retailers compete for both demand and supply, they tend to over‐order. We show that a combination of a pay back and revenue sharing mechanism can coordinate the supply chain, with the pay back mechanism correcting the supplier's under‐producing problem and the revenue sharing mechanism correcting the retailers' over‐ordering problem. When demand is stochastic, we consider a modified pay‐back‐revenue‐sharing contract under which the retailer agrees to not only purchase the supplier's excess output (beyond the retailer's order), but also share with the supplier a portion of the revenue made from the sales of the excess output. We show that this contract, by giving the supplier additional incentives in the form of revenue share, can achieve coordination.