考虑供应链中断风险的最优供应商数量决策北大核心CSSCI

针对存在供应链中断风险的供应商数量选择问题,分析了由交易成本、风险损失、采购成本构成的采购总成本与供应商数量的关系。首先考虑到供应商的供应风险和市场的需求风险,引入数量弹性契约,对供应链中断风险进行了考察。然后在此基础上,构建了以采购总成本最小化为目标的考虑供应链中断风险的最优供应商数量决策模型。最后,通过算例分析验证了该模型的可行性,并探讨了机会主义成本、合作程度、市场需求均值、弹性系数、供应风险概率等相关参数对最优供应商数量的影响。     

考虑供应链中断风险的最优供应商数量决策

针对存在供应链中断风险的供应商数量选择问题,分析了由交易成本、风险损失、采购成本构成的采购总成本与供应商数量的关系。首先考虑到供应商的供应风险和市场的需求风险,引入数量弹性契约,对供应链中断风险进行了考察。然后在此基础上,构建了以采购总成本最小化为目标的考虑供应链中断风险的最优供应商数量决策模型。最后,通过算例分析验证了该模型的可行性,并探讨了机会主义成本、合作程度、市场需求均值、弹性系数、供应风险概率等相关参数对最优供应商数量的影响。     

基于风险防范的供应商数量优化决策

在公开透明的市场环境下,从制造商采购原材料的采购总成本出发,建立了一个基于风险防范的供应商数量优化模型。该模型描述了影响采购总成本的各个因素,并引入了风险规避系数,将供应商的供应风险定量化、成本化。通过算例,分析了风险规避系数、供应中断概率以及中断后造成的企业财务损失等风险因素对最优供应商数量的影响。     

产能与需求不确定下基于MOI和VMI的供应链比较研究

为分析供应链运作机制对降低产能不确定和需求不确定的影响,对比研究了MOI和VMI两种供应链运作模式下单关键零部件供应商-单制造商组成的两级供应链系统。MOI模式下,制造商负责产品的库存决策,并承担相应的零部件库存成本和缺货成本;VMI模式下,供应商负责产品的库存决策和额外产能储备决策,并承担相应的零部件库存成本和过剩能力闲置成本。给出了供应链的最优解及期望利润;为进一步讨论供应链管理模式对提升供应链运作效率的管理意义,分析了随机需求、随机产能及批发价格对两种模式的影响。     

未知需求分布下提前期可控的整合库存模型研究

考虑了单供应商单采购商的生产一库存联合优化问题,采购商面临未知分布的随机需求,供应商的提前期可以控制.采用Minimax方法建立了供应商和采购商联合期望总成本最小化模型,模型中允许采购商缺货,并且部分缺货延期交付,部分缺货发生销售损失,同时也考虑了运输成本,并且假设运输成本依赖于订货量和提前期.给出了求解联合最优生产批...     

供应不确定下制造商的采购策略:回收或双渠道采购

在考虑供应商供应不确定的情形下,构建制造商在不同市场结构下的采购策略选择模型,研究发现:①垄断市场中,当供应不确定性较大时,制造商会选择回收策略;当供应商的不确定性较小时,制造商选择双渠道采购。②竞争市场中对比制造商的均衡利润发现,当供应商供应不确定性大时,两制造商均选择回收策略达到纳什均衡;当供应不确定性处于中间水平时,两制造商选择差异化的采购策略更有利可图;当供应商供应不确定性小时,上游供应商之间的竞争激烈,双渠道采购为市场的均衡策略。此外,还探讨了供应不确定性的变化对制造商的利润影响。     

基于防范机会主义的供应商数量研究

按照综合考虑有效抑制机会主义的负面作用和充分发挥合作的积极作用的准则,构建了供应商数量决策模型,求出了最优供应商数量的解.研究表明:最优供应商数量是合作效益的减函数、机会主义损失的增函数以及交易成本的减函数.若合作带来的供应商边际生产成本的节约相对于机会主义损失更大,买方应选择少供应商,反之,则倾向于多供应商;边际交易成本越大,买方选择的供应商数量应越少.单一供应商策略只适合于合作效益足够大或边际交易成本过大的特殊场合.     

不对称信息下考虑供应中断和延期交货的采购合同设计

研究不对称信息下供应商供应中断和延期交货两类风险对制造商采购决策的影响。运用采购机制设计理论与方法,分析了制造商最优采购合同及供应商最优生产决策。结果表明:1)供应商生产数量和交货提前期应分别用中断罚金和延期罚金规制;2)供应商有关供应可靠性的私有信息使高类型供应商的两类罚金均增加,交货提前期缩短;同时,低类型供应商的中断罚金减小,延期罚金和交货提前期不受影响;3)信息不对称不一定降低社会福利。     

产能不确定环境下多供应商横向协同问题研究

为了减轻零部件产能不确定性所造成的制造商过高库存成本的影响,采用信息共享或者加班赶工及资源外包的方式,建立了多个供应商之间的两种横向协同模型,减量模型和增量模型.通过数据仿真的结果显示,相比于非协同模型,这两种协同模型能够明显地降低制造商的缺货成本和购买成本,同时消除了多余未齐套零部件的库存持有成本,最终有效地降低了制...     

基于区块链技术的供应链主体风险规避研究

基于区块链技术对于供应链参与者信息共享的影响为前提,运用条件风险价值法刻画零售商风险,采用Stackelberg博弈研究由零售商、供应商、物流服务集成商组成的三级供应链上参与者在分散决策与集中决策下的期望利润。研究表明:分散决策下,零售商的最优订购量随着风险规避系数的增加而增加,但供应商区块链技术应用程度随着零售商风险规避系数的增加而减小。集中决策下,决策者在风险中性时的供应链整体利润大于部分集中和分散决策下的利润;不考虑缺货损失风险下的供应链最优的利润将大于考虑缺货损失时的利润;通过利用区块链技术可以减少供应链成员间的交易成本,实现信息共享,从而提高供应链的整体利润。     

广告视角下智能小区实时定价博弈分析

考虑连续时间内供电商对用户的争抢行为，将广告微分博弈引入智能电网系统中以刻画供电商之间的相互竞争，并建立多供电商多用户Stackelberg博弈模型研究智能电网实时定价问题。通过求解用户侧优化问题及供电商之间非合作微分博弈纳什均衡，最终获得供电商与用户之间Stackelberg博弈均衡，以此得到供电商广告竞争下的智能电网实时电价。数值仿真结果表明：采取广告行为供电商的最大支付随其广告成本和定价先增后减，而随用户规模扩大而递增；另外，随着单位广告成本的增加，供电商统一电价逐渐降低，带来用户效用提高，且拥有较低广告成本的供电商售电较多。     

基于损失成本理论的供应商持续改进评价

利用质量成本理论中的损失成本理论，将供应商所导致的损失成本作为评价供应商绩效的标准。通过ABC分析，发现了供应商和供应商主要问题之所在，对供应商自身以及供应商之间作了比较评价，以促使供应商的持续改进。     

Controlling a supplier’s subcontracting decisions through contractual enforcement or economic incentives

Suppliers often subcontract part of their workload to other suppliers, and manufacturers might suffer severe consequences if they do not anticipate their suppliers’ incentives to subcontract. In this paper, we study the case where a manufacturer outsources two tasks to a top-tier supplier. The manufacturer must decide whether it should design a contract that enforces that the different tasks are completed by the appropriate suppliers, and when it is preferable to use economic incentives to manipulate the top-tier supplier’s subcontracting behaviour. We find that when the cost difference between suppliers of different tiers is small and the correlation between the risks associated with the two tasks is minimal, the manufacturer can benefit from designing a contract that ensures the preferred subcontracting behaviour, if the cost of enforcing such a contract is not too high. However, when such enforcement cost is substantial, the manufacturer might be better off manipulating the top-tier supplier’s economic incentives.     

DUAL SOURCING COST-OPTIMIZATION WITH UNRESTRICTED LEAD-TIME DISTRIBUTIONS AND ORDER-SPLIT PROPORTIONS

Among recent studies considering the splitting of an order among several suppliers (i.e., in “multiple sourcing”), one group considered only the favorable effect of multiple suppliers on the effective lead time demand and required safety stock, but its effects on the annual order and holding cost components have been ignored. Another group that considers the effect of using two suppliers on all relevant cost components imposes severe restrictions on the suppliers' lead-time distributions as well as the proportion of order-split between the suppliers. Our primary purpose is to present easily-solvable decision models for minimizing the sum of annual holding and ordering costs with two suppliers, subject to a maximum allowable stockout risk; restrictions on lead-time distributions and order-split proportion are completely eliminated. Solving these models gives the optimal total order quantity, reorder point and proportion of split between the two suppliers. Numerical results from our models reveal some unexpected observations; e.g.: (i) In using two suppliers, die reduction of inventory carrying cost (a hitherto unrecognized component) is at least as important, and often considerably more important than the effect of safety-stock-cost reduction, (ii) Although intuitively one might use suppliers with the shortest (mean) lead times, it is actually better to have two suppliers such mat the second supplier's mean lead time is “suitably” larger man the first's; this could mean excluding the one with lowest mean lead times among the candidates for the second supplier, (iii) The optimal proportion of split varies with, among other factors, the difference in the suppliers' mean lead times.     

A dynamic sourcing strategy considering supply disruption risks

This study presents a formulation that supports decision-making by determining the optimal number of standby suppliers required to respond to supply failure risks. The problem of supply failure is modelled through a standby approach, in which failure is time-dependent. The probabilities of supply interruption, financial loss caused by supply failure, and operating cost of working with suppliers are modelled to yield the expected total cost, which enables organisations to determine the optimal number of suppliers. Two possible modes of substitution failure are considered in the standby model to enhance the analysis. A set of sensitivity analyses are performed for several input parameters to illustrate the model’s behaviour. The analysis provides an optimal sourcing strategy depending on a combination of supply risk, operational cost vs. loss ratio and length of the supply period. The proposed model indicates the benefits of cost savings, unlike other dynamic models that use multiple suppliers simultaneously.     

A branch-and-bound algorithm for the concave cost supply problem

Effective supplier selection and allocation of order quantity among multiple suppliers are indispensable to the success of a manufacturing company. While companies have begun to turn into a comprehensive multi-criteria approach, most buyers still consider purchasing cost to be their primary concern in selecting their suppliers. In this paper, we consider the concave cost supply problem where a manufacturer seeks to select the suppliers and simultaneously procure the quantity of material/component required for production at the minimum total cost during a standard production period. We provide and validate an effective and efficient branch-and-bound algorithm that is finite and that finds the global optimal solution of the problem without any restrictions on the cost functions or on the set of input parameters used in the problem. Numerical experiments are conducted to evaluate the performance of the proposed algorithm.     

第三方资金流提供商的采购协同问题研究

在传统的供应链采购运作过程中,由于核心制造商一直对其供应商供货采取下线结算的方式,从而导致供应商一直承担着巨大的库存持有成本.在基于Supply Hub的供应链运作模式下,提出了一种新的资金结算方式:令传统的3PL充当第三方资金流提供商来对供应商提前支付货款.从而解决供应商库存成本压力过大的问题,并且实现对资金流、信息流、物流的整合.在新的结算模式下,通过对供应链的成本分析研究得出一种有效的供应链运作机制,从而提高供应商的响应速度及协同性,降低供应链的总成本.通过数据模拟进一步证明.在该模式下核心制造商能够获得更快的产品交货期;供应商能够有效地降低库存持有成本;第三方资金流提供商可以通过对供应商采取适当的惩罚来约束供应商,促使供应商对交货期做出最合适的选择,并且使自身获利.     

A two objective optimisation model for order splitting among parallel suppliers

To correctly split an order among parallel suppliers is one of the most important ways to improve the agility and competitiveness of a supply chain. For this order splitting problem, an evaluation criterion of production load equilibrium among parallel suppliers is introduced and a two objective order splitting model is developed to minimise the comprehensive cost and balance the production loads among the selected suppliers. The procedure of the suppliers’ selection is proposed and non-dominated sorting genetic algorithm (NSGA-II) is applied to find the feasible solution set of Pareto. The simulation results indicate that the proposed model and algorithm is capable of obtaining satisfactory solutions.     

Impact of risk aversion and backup supplier on sourcing decisions of a firm

This study focuses on a newsvendor problem with multiple suppliers, considering the risk-neutral and risk-averse objectives in a mean-risk optimisation model. The firm first decides order quantities from the primary (unreliable) suppliers and reserve capacity from the secondary (reliable) backup supplier. After the state of its primary suppliers and customer demand is revealed, the firm purchases from the available suppliers and uses the backup supplier subject to the reserved capacity. For the special case of normal distribution and risk-neutral objective, optimality properties were developed. A comprehensive numerical study examines the sensitivity of the sourcing strategies of firms to risk, shortage cost, demand uncertainty, salvage value, and capacity reserve options; various managerial insights are offered based on this.     

Supply management in assembly systems with random yield and random demand

In this paper, we consider an assembly system where a firm faces random demand for a finished product which is assembled using two critical components. The components are procured from the suppliers who, due to production yield losses, deliver a random fraction of the order quantity. We formulate the exact cost function where the decision variables are the target level of finished products to assemble, and the order quantity of the components from the suppliers. Since the exact cost function is analytically complex to solve, we introduce a modified cost function and derive bounds on the difference in the objective function values. Using the modified cost function, we determine the combined component ordering and production (assembly) decisions for the firm. The benefit of coordinating ordering and assembly decisions is numerically demonstrated by comparing the results with two heuristic policies commonly used in practice. In an extension to the model, we consider the case when the firm has the added option of ordering both the components in a set from a joint supplier. First, we consider the case when the joint supplier is reliable in delivery and obtain dominance conditions on the suppliers to be chosen. The maximum price a firm would be willing to pay to ensure reliable supply of components is determined. Later, we consider the uncertainty in the deliveries from the joint supplier and determine conditions under which there is no diversification, that is, either the individual suppliers are used, or the joint supplier is used, but never both.