Multitiered Supply Chain Networks: Multicriteria Decision—Making Under Uncertainty

In this paper, we present a supply chain network model with multiple tiers of decision-makers, consisting, respectively, of manufacturers, distributors, and retailers, who can compete within a tier but may cooperate between tiers. We consider multicriteria decision-making for both the manufacturers and the distributors whereas the retailers are subject to decision-making under uncertainty since the demands associated with the product are random. We derive the optimality conditions for the decision-makers, establish the equilibrium conditions, and derive the variational inequality formulation. We then utilize the variational inequality formulation to provide both qualitative properties of the equilibrium product shipment, service level, and price pattern and to propose a computational procedure, along with convergence results. This is the first supply chain network model to capture both multicriteria decision-making and decision-making under uncertainty in an integrated equilibrium framework.     

A supply chain network equilibrium model with random demands

In this paper, we develop a supply chain network model consisting of manufacturers and retailers in which the demands associated with the retail outlets are random. We model the optimizing behavior of the various decision-makers, derive the equilibrium conditions, and establish the finite-dimensional variational inequality formulation. We provide qualitative properties of the equilibrium pattern in terms of existence and uniqueness results and also establish conditions under which the proposed computational procedure is guaranteed to converge. Finally, we illustrate the model through several numerical examples for which the equilibrium prices and product shipments are computed. This is the first supply chain network equilibrium model with random demands for which modeling, qualitative analysis, and computational results have been obtained.     

Dynamics of supply chain networks with corporate social responsibility through integrated environmental decision-making

In this paper, we develop a dynamic framework for the modeling and analysis of supply chain networks with corporate social responsibility through integrated environmental decision-making. Through a multilevel supply chain network, we model the multicriteria decision-making behavior of the various decision-makers (manufacturers, retailers, and consumers), which includes the maximization of profit, the minimization of emission (waste), and the minimization of risk. We explore the dynamic evolution of the product flows, the associated product prices, as well as the levels of social responsibility activities on the network until an equilibrium pattern is achieved. We provide some qualitative properties of the dynamic trajectories, under suitable assumptions, and propose a discrete-time algorithm which is then applied to track the evolution of the levels of social responsibility activities, product flows and prices over time. We illustrate the model and computational procedure with several numerical examples.     

多目标供应链网络平衡模型

针对生产商、零售商和消费群三层决策者问题建立了一个多目标供应链网络均衡模型.给出此模型的均衡条件,并讨论了(弱)均衡解和标量化解之间的关系.最后,给出具体的例子说明此模型.     

Supply chain networks with global outsourcing and quick-response production under demand and cost uncertainty

This paper develops a modeling and computational framework for supply chain networks with global outsourcing and quick-response production under demand and cost uncertainty. Our model considers multiple off-shore suppliers, multiple manufacturers, and multiple demand markets. Using variational inequality theory, we formulate the governing equilibrium conditions of the competing decision-makers (the manufacturers) who are faced with two-stage stochastic programming problems but who also have to cooperate with the other decision-makers (the off-shore suppliers). Our theoretical and analytical results shed light on the value of outsourcing from novel real option perspectives. Moreover, our simulation studies reveal important managerial insights regarding how demand and cost uncertainty affects the profits, the risks, as well as the global outsourcing and quick-production decisions of supply chain firms under competition.     

多商品流电子商务供应链网络模型

针对多商品流三层供应链网络模型,将电子商务整合到多商品流供应链网络中,导出了每层网络代理商或决策者的最优性条件,给出了问题的变分不等式形式,得到了系统达到均衡的条件,给出了具体算例并进行了求解.     

动态供应链网络均衡模型构建与分析

基于单一商品流,考虑了时间变量和库存问题,建立了三层动态供应链网络结构模型.对制造商、零售商和需求市场的多期独立决策行为及其相互作用进行了分析,应用变分不等式构建了各层均衡模型和整个供应链网络均衡模型.最后与相关文献的模型进行了比较.     

International financial networks with intermediation: modeling,analysis, and computations

In this paper, we develop a framework for the modeling, analysis, and computation of solutions to international financial networks with intermediation. We consider three tiers of decision-makers consisting of: source agents in different countries, financial intermediaries, and consumers associated with the demand markets for different products in distinct currencies and countries. We model the behavior of the decision-makers, derive the equilibrium conditions, and establish the variational inequality formulation. We then utilize the variational inequality formulation to obtain qualitative properties of the equilibrium financial flow and price pattern as well as to propose an algorithm along with convergence results. Numerical examples are presented to illustrate both the model and the computational procedure. This research extends the recent results surrounding the modeling of financial networks with intermediation to the international dimension.Revised: January 2003, AMS Classification: 90, 91     

具过度自信零售商的双渠道供应链网络均衡研究

将零售商的过度自信行为纳入双渠道供应链网络均衡模型,研究了由供应商、分销商以及具过度自信行为的零售商构成双渠道供应链网络均衡问题。借助变分不等式以及互补理论,刻画了制造商、分销商以及过度自信零售商的最优行为,并构建了双渠道供应链网络均衡条件。解析分析了市场出现有利信息和不利信息两种情形下,零售商的过度自信行为对其订购决策的影响。最后,数值算例验证上述结论,并借助数值结果分析了零售商的过度自信行为对双渠道网络均衡的影响。     

随机需求下考虑风险行为的闭环供应链网络均衡模型

以变分不等式和均衡理论为基本研究工具,研究了随机需求与再制造率不确定条件下多个竞争型的供应商、制造商、零售商及消费市场的行为及均衡条件。对所建立的多级闭环供应链网络均衡模型,通过拟牛顿算法求解变分不等式,并仿真分析了再制造率、回收率以及风险因素对闭环供应链网络均衡结果的影响。结果表明:制造商提高再制造率能实现供应链成员利润的增加、产品价格的降低以及回收量的增加;制造商基于风险最小化和利润最大化相结合的原则进行决策能增加产品的交易量及企业的利润。     

由零售商负责回收的多期闭环供应链网络均衡

本文研究了零售商回收模式下多期闭环供应链网络均衡问题。制造商通过零售渠道将产品销售给消费者,以满足消费市场需求,同时消费产生的废旧品由零售商回收返回制造商处进行再制造,通过产品库存和回收废旧品连接相邻规划期。运用变分不等式理论和互补理论,分别刻画了制造市场、零售市场和消费市场的均衡,接着构建了多期闭环供应链网络均衡模型。利用变分不等式的投影收缩算法,对模型进行求解。算例着重分析了废旧品利用率对网络均衡状态和供应链成员利润的影响。结果表明:当制造商的废旧品利用率逐渐增加时,回收量逐渐增加,制造商的利润先减后增,零售商利润一直增加,而供应链总利润一直增加,供应链网络中的最优决策变量主要受到回收量约束的影响。     

带有环境指示因子的闭环供应链网络均衡的互补模型研究

以非线性互补理论为基本工具,提出带有环境指示因子且由原料供应商、制造商、零售商、需求市场及回收中心组成的闭环供应链网络均衡。鉴于对可持续发展的日益关注,环境保护部门通过实施对制造商的排放进行惩罚的机制以遏制其污染行为,同时通过对回收中心的回收实行奖励的机制以激励其回收行为。排放惩罚与回收奖励应大于相应的影子价格,这些影子价格作为环境指示因子由模型决定且有益于政府部门制定相应环保政策。在描述不同决策者优化行为的基础上推导最优性条件,得到对应于闭环供应链网络均衡问题的非线性互补模型,证明解的存在性进而构造数值算例以验证模型的合理性。     

基于风险管理的动态供应链超网络均衡模型

基于风险管理的动态供应链超网络均衡模型的研究有助于供应链超网络节点厂商在动态环境下优化其风险管理,降低风险损失,提升供应链网络在风险管理下的竞争优势。本文以三层供应链超网络为研究对象,采用风险发生概率和损失函数表达供应链超网络中节点厂商中断风险的特征,构建了基于风险管理的动态供应链超网络均衡模型。模型中包括三种类型的节点,产品生产商、零售商和需求市场,生产商考虑风险损失的情况下,基于动态变化的风险、需求和成本追求个体期望效益最优化。接着,通过进化变分不等式来表达动态供应链超网络风险管理下的均衡解,并采用投影动态系统求解进化变分不等式,通过数值算例验证方法的可靠性和合理性,通过投影动态系统解释某一个厂商趋近均衡解的过程。通过单一厂商趋近均衡解的过程,阐述其他厂商相应的最优决策。     

Equilibrium analysis and corporate social responsibility for supply chain integration

This paper evaluates the profit of coordination between manufacturers on corporate social responsibility (CSR) under network equilibrium. A three-tier supply chain network with multiple manufacturers, distributors, and retailers is considered, and several mathematical models are established to investigate behavior and profits in a decentralized supply chain network, a centralized supply chain network, and a supply chain network with CSR. The system-optimal solution of a supply chain network problem is usually not achievable or stable since each member always tries to maximize its own profit. In order to make such a system-optimal solution in a stable state and ensure the maximization of total profits, a strategy of coordination between manufacturers on CSR is proposed. The amount of payment in CSR of each manufacturer is clearly defined. A hybrid diagonalization method with a super-network representation is proposed and tested with numerical examples. The results show that by taking CSR, the total profits of the whole supply chain network can increase with or without coordination.     

Formulation and analysis of horizontal mergers among oligopolistic firms with insights into the merger paradox: a supply chain network perspective

In this paper, we consider oligopolistic firms with supply chain networks who are involved in the production, storage, and distribution of a homogeneous product to demand markets and explore what has become known in the literature as the “merger paradox.” We present the oligopolistic supply chain network equilibrium model associated with the competing firms before the horizontal mergers and also develop the supply chain network optimization model post the complete merger. In addition, we develop the model in which only a subset of the firms in the industry merge. The governing concept of the competing firms is that of Cournot–Nash equilibrium. We utilize finite-dimensional variational inequality theory for the formulation, analysis, and solution of both the pre and the post-merger supply chain network problems. We provide numerical examples for which we compute the total costs, the total revenues, as well as the profits obtained for the firms pre and post the mergers for a variety of distinct oligopoly problems. The generality of the network models and the flexibility of the computational approach, which yields closed form expressions for the product flows at each iteration, allows us to obtain deeper insights into the merger paradox.     

Financial networks with intermediation: Risk management with variable weights

In this paper, we develop a framework for the modeling, analysis, and computation of solutions to multitiered financial network problems with intermediaries in which both the sources of financial funds as well as the intermediaries are multicriteria decision-makers. In particular, we assume that these decision-makers seek not only to maximize their net revenues but also to minimize risk with the risk being penalized by a variable weight. We make explicit the behavior of the various decision-makers, including the consumers at the demand markets for the financial products. We derive the optimality conditions, and demonstrate that the governing equilibrium conditions of the financial network economy can be formulated as a finite-dimensional variational inequality problem. Qualitative properties of the equilibrium financial flow and price pattern are provided. A computational procedure that exploits the network structure of the problem is proposed and then applied to several numerical examples.     

Modeling and analysis of the multiperiod effects of social relationship on supply chain networks

In this paper, we analyze the effects of levels of social relationship on a multiperiod supply chain network with multiple decision-makers (suppliers, manufacturers, and retailers) associated at different tiers. The model incorporates the individual attitudes towards disruption and opportunism risks and allows us to investigate the interplay of the heterogeneous decision-makers and to compute the resultant network equilibrium pattern of production, transactions, prices, and levels of social relationship over the multiperiod planning horizon. In our analysis, we focus on the following questions: (1) how do the evolving relationships affect the profitability and risks of supply chain firms as well as the prices and demands of the product in the market? (2) how do the relationships with the upstream supply chain firms affect the relationships with the downstream firms, and how these relationships influence the profitability and risks of the supply chain firms? (3) how do the supply disruption risks interact with the opportunism risks through supply chain relationships, and how these risks influence the profitability of the firms? The results show that high levels of relationship can lead to lower supply chain overall cost, lower risk, lower prices, higher product transaction and therefore higher profit.     

基于惩罚与补贴的再制造闭环供应链网络均衡模型

为研究我国废旧电子产品(WEEE)立法的问题,分析了供应商、制造商、零售商、需求市场及回收商的行为,分别建立了变分不等式模型,并在此基础上建立了五级再制造闭环供应链网络均衡模型。模型考虑了政府对于制造商的惩罚政策与对于回收商的补贴政策。通过修正投影算法求解算例,仿真分析了旧材料转化率、回收率、惩罚及补贴政策对闭环供应链网络均衡结果的影响。结果表明,随着政府对于回收商的补贴的增加,不但回收商的回收量提高,闭环供应链的新材料需求量、旧材料需求量、销售量均增加;相反,随着政府对于制造商未完成的回收量的罚款增加,回收量、新材料需求量、旧材料需求量、销售量均降低;追求高回收率的政策并不总是有效的;而提高WEEE的旧材料转化率对于闭环供应链有利。     

基于变分不等式的闭环供应链超网络模型研究

建立了一个由原材料供应商、生产商、零售商、需求市场和回收中心组成的闭环供应链超网络模型.利用均衡理论以及变分不等式的方法分析网络中各层决策者的独立行为及其相互作用进而得到了该系统达到均衡状态的条件.最后,设计了一个数值算例就旧产品的回收率和利用率及旧材料的利用率等参量对超网络系统的运作性能的影响进行了分析同时也验证了该超网络模型的有效性.     

Supply chain networks,wages, and labor productivity: insights from Lagrange. analysis and computations

The COVID-19 pandemic has dramatically demonstrated the importance of labor to supply chain network activities from production to distribution with shortfalls in labor availability, for numerous reasons, resulting in product shortages and the reduction of profits of firms. Even as progress has been made through vaccinations, issues associated with labor are still arising. Increasing wages is a strategy to enhance labor productivity and, also to ameliorate, in part, labor shortages, but has not, until this work, been explored in a full supply chain network context. Specifically, in this paper, a game theory supply chain network model is constructed of firms competing in producing a substitutable, but differentiated, product, and seeking to determine their equilibrium product path flows, as well as hourly wages to pay their workers, under fixed labor amounts associated with links, and wage-responsive productivity factors. The theoretical and computational approach utilizes the theory of variational inequalities. We first introduce a model without wage bounds on links and then extend it to include wage bounds. Lagrange analysis is conducted for the latter model, which yields interesting insights, as well as an alternative variational inequality formulation. A series of numerical examples reveals that firms can gain in terms of profits by being willing to pay higher wages, resulting in benefits also for their workers, as well as consumers, who enjoy lower demand market prices for the products. However, sensitivity analysis should be conducted to determine the range of such wage bounds. Ultimately, we observed, that the profits may decrease and then stabilize. This work adds to the literature on the integration of concepts from economics and operations research for supply chain networks and also has policy implications.