A supply chain-transport supernetwork equilibrium model with the behaviour of freight carriers

This paper presents a supernetwork equilibrium model integrating supply chain networks with a transport network, namely, a supply chain-transport supernetwork equilibrium model. The model takes into account the behaviour of freight carriers and transport network users to endogenously determine the transport costs generated in the supply chain networks. The interaction between transport network and supply chain networks can also be examined. Results of the numerical tests reveal that the improvement of transport network could enhance the efficiency of supply chain networks. The paper makes contributions to modelling of supply chain networks as well as to that of transport networks.     

Dynamic electric power supply chains and transportation networks: An evolutionary variational inequality formulation

In this paper, we develop a static electric power supply chain network equilibrium model with known demands and establish the equivalence between the model and a transportation network equilibrium model with fixed demands over an appropriately constructed supernetwork. This equivalence yields a new interpretation of electric power supply chain network equilibria in path flows. We then exploit this equivalence to propose a dynamic electric power supply chain network model in which the demand varies over time using an evolutionary variational inequality formulation. Finally, we demonstrate how numerical dynamic electric power supply chain network problems can be solved utilizing recently obtained theoretical results in the unification of evolutionary variational inequalities and projected dynamical systems.     

Freight transport network design using particle swarm optimisation in supply chain–transport supernetwork equilibrium

This paper presents a discrete network design problem for optimally designing freight transport network in terms of the efficiency of supply chain. Modelling is undertaken within the framework of mathematical programmes with equilibrium constraints, which first incorporates both supply chain and transport networks explicitly. The upper level determines the best set of actions for transport network improvement, while the lower-level decision is based on a supply chain–multimodal transport supernetwork equilibrium. New variants of particle swarm optimisation are developed to approximately solve the upper level. Numerical tests reveal their superior performance and the effective freight transport-related actions.     

The equilibrium of closed-loop supply chain supernetwork with time-dependent parameters

In this paper, we develop a closed-loop supply chain supernetwork model including suppliers, manufacturers, retailers and consumers at demand market, in which the demand for product is seasonal (t), and the sensitivity (w) of demand to price is another key factor which effects consumers’ demand. Moreover, the manufacturers invest the reverse distribution channel for incenting consumers to return more used products. Based on the Evolutionary Variational Inequalities (EVI) theory and Projected Dynamical Systems (PDS), the equilibrium condition of closed-loop supply chain is formulated, and the model is verified reasonably by numerical example.     

Supply chain network design under profit maximization and oligopolistic competition

In this paper, we model the supply chain network design problem with oligopolistic firms who are involved in the competitive production, storage, and distribution of a homogeneous product to multiple demand markets. The profit-maximizing firms select both the capacities associated with the various supply chain network activities as well as the product quantities. We formulate the governing Nash–Cournot equilibrium conditions as a variational inequality problem and identify several special cases of the model, notably, a generalization of a spatial oligopoly and a classical oligopoly problem to include design capacity variables. The proposed computational approach, which is based on projected dynamical systems, fully exploits the network structure of the problems and yields closed form solutions at each iteration. In order to illustrate the modeling framework and the algorithm, we also provide solutions to a spectrum of numerical supply chain network oligopoly design examples.This paper makes a contribution to game theoretic modeling of competitive supply chain network design problems in an oligopolistic setting.     

The e-supply chain portal: a core business model

Information technology can help to overcome the problems that plague many supply chains. Electronic exchange of information leads to reduction of errors and increased efficiency of the work processes. When one company can use the information of other companies in the supply chain, the negative effects of uncertainty can be mitigated in theory. In practice, however, the exchange of information between companies is not as easy as it seems. Many different systems and standards are used, the number of peer-to-peer relations with other companies in the network is usually too large to manage, most systems are not open for easy exchange of information with other systems, and most companies are very reluctant to share information with other companies in the first place.A portal looks like a good solution to overcome these problems. Standardized interactions with one portal are easier to manage than are many peer-to-peer relations. The portal can take the role of a trusted party. What is needed to accomplish portal effectiveness is a review of the business processes when dealing with other companies. In this paper, we advocate a radical simplification of these business processes, and provide support for the end-to-end character of the supply chain in real time. Specifically, we report on a pilot project for the US Department of Defense to create a portal for supply chain integration. The project showed the feasibility of real-time support for end-to-end supply chain management in a complex organization.     

Optimizing inventory decisions in a multi-stage multi-customer supply chain

Most supply chain models focus on two-stage chains in which vendors supply material to one customer. In this paper, we formulate a three-stage supply chain model where a firm can supply many customers. We deal with three inventory coordination mechanisms between chain members and solve a cost minimization model for each. We show that some of the coordination mechanisms can result in a significantly lower total cost than matching production and delivery along the chain. We provide some insights into when the added complexity of the second and third coordination mechanisms lead to significant cost reductions.     

Optimizing inventory decisions in a multi-stage multi-customer supply chain: A note

In this paper, we propose an n-stage-multi-customer supply chain inventory model where there is a company that can supply products to several customers. We formulate the model for the simplest inventory coordination mechanism which is referred to as the same cycle time for all companies in the supply chain. We conclude that it is possible to use an algebraic approach to optimize the supply chain model without the use of differential calculus.     

A generalized algebraic model for optimizing inventory decisions in a multi-stage complex supply chain

In this paper, we deal with more generalized inventory coordination mechanism in an n-stage, multi-customer, non-serial supply chain, where we extend and generalize pervious works that use algebraic methods to optimize this coordinated supply chain. We establish the recursive expressions for this multi-variable optimization problem. These expressions are used for the derivation of the optimal replenishment policy and the development of the solution algorithm. Further, we describe a simple procedure that can help in sharing the coordination cost benefits to induce all stages to adopt the inventory coordination mechanism. We provide a numerical example for illustrative purposes.     

Global supply chain design: A literature review and critique

In this paper, we review decision support models for the design of global supply chains, and assess the fit between the research literature in this area and the practical issues of global supply chain design. The classification scheme for this review is based on ongoing and emerging issues in global supply chain management and includes review dimensions for (1) decisions addressed in the model, (2) performance metrics, (3) the degree to which the model supports integrated decision processes, and (4) globalization considerations. We conclude that although most models resolve a difficult feature associated with globalization, few models address the practical global supply chain design problem in its entirety. We close the paper with recommendations for future research in global supply chain modeling that is both forward-looking and practically oriented.     

Production smoothing in a serial supply chain: A laboratory investigation

The purpose of this paper is to examine production smoothing in supply chains. Using the controlled setting of the laboratory, we systematically investigate supply chain features that lead to production smoothing. In contrast to prior laboratory studies of the bullwhip effect, we find that the bullwhip effect disappears in several of our experiments. More importantly, our study shows that when customer demand has a predictable seasonal component, retailers smooth orders. This behavior is more pronounced when changing order levels is costly. The results demonstrate how simplifying the structure of the supply chain leads to production smoothing behavior.     

供应链的战略管理模型研究

强调成本的有效性供应链和强调时间反应速度的反应性供应链是两种完全不同的供应链战略。企业在强调成本时不能完全忽略供应链的时间效用,同样在强调反应速度时也无法完全忽视成本的影响,因此通过对供应链战略的分析,对成本和时间赋予一定的权重,建立综合成本和反应速度的供应链战略模型,并通过实例对模型进行了验证。     

Marrying supply chain sustainability and resilience: A match made in heaven

Sustainable supply chain management has become an integral part of corporate strategy for virtually every industry. However, little is understood about the broader impacts of sustainability practices on the capacity of the supply chain to tolerate disruptions. This article aims to explore the sustainability–resilience relationship at the supply chain design level. A multi-objective optimization model featuring a sustainability performance scoring method and a stochastic fuzzy goal programming approach is developed that can be used to perform a dynamic sustainability tradeoff analysis and design a “resiliently sustainable” supply chain. Important managerial and practical insights are obtained from an empirical case study.     

The influence of green practices on supply chain performance: A case study approach

The main objective of this exploratory paper is to investigate the relationships between green practices of supply chain management and supply chain performance. This relationship is investigated in the context of the automotive industry. Five research propositions are suggested and tested with empirical data derived from five case studies taken from the Portuguese automotive supply chain. The data analysis identifies the most important green practices considered by managers, as well as the performance measures that are most appropriate and most widely used as means to evaluate the influence of green practices on supply chain performance. A conceptual model was derived from the data analysis and it can be used to assess the influence of green practices on supply chain performance. This model provides evidence as to which green practices have positive effects on quality, customer satisfaction and efficiency. It also identifies the practices which have negative effects on supply chain performance.     

Supply chain micro-communities in urban areas

An increase in urban freight transport is inevitable as growing urban populations require more goods, more conveniently. A deeper understanding of the geography and trends of urban freight transport must recognise that it is the aggregate result of a complex web of supply chain interactions. To understand the trends, the behaviour of the underlying supply chains must be understood. Using Global Positioning System (GPS) traces of commercial vehicles and network theory concepts, this paper examines the characteristics of supply chain micro-communities in three urban areas in South Africa. The similarity in the structure of these micro-communities across the three, very diverse, areas suggests that the dynamics that drive supply chain interaction are not dependent on local geography. Four prominent archetypes were identified that account for more than half of the micro-communities in each area. Directionality, geographic dispersion and the balance of importance in the micro-communities are studied in the context of these archetypes. This paper presents a first puzzle piece in deducing urban freight transport patterns from supply chain interaction. Furthermore the results are an empirical benchmark that can validate theoretic models of urban supply chain interaction.     

The environmental benefits of changing logistics structures for fresh vegetables

The transport phase is one of the crucial stages that can be improved to reduce the environmental impact of the fresh fruit and vegetable supply chain. In this paper, we calculate the environmental impact of feasible logistic alternatives for the above-mentioned supply chain so as to identify the type of transportation that incurs the lowest environmental costs. Specifically, we consider the early potato supply chain as a case study, as it involves one of the main fresh vegetables exported from Italy. Consumers' willingness to pay for the environmental impact of different logistic chains was obtained through life cycle assessment. Our results show that rail transport could reduce environmental impact in terms of tons of oil equivalent, environmental loads, and fuel consumption while ensuring reasonable shipment times. Development of an efficient rail transport system would be positively considered by consumers, enhancing their preferences for Italian products.     

Supply chain design under quality disruptions and tainted materials delivery

Events such as the 2008 Heparin tragedy, in which patients lost their lives due to tainted pharmaceuticals, highlight the necessity for supply chain designers and planners to consider the risk of even low probability incidents in supply chains. The goal of this research is to design a single-period, single-product supply chain model with capacitated facilities to hedge against the possibility of sending tainted materials to consumers. Given that our mixed-integer stochastic model is NP-hard, we develop efficient heuristic and metaheuristic algorithms to obtain acceptable solutions. Computational experience is presented and discussed.     

The impact of transportation disruptions on supply chain performance

This paper investigates the effect of a transportation disruption on supply chain performance using system dynamics simulation, comparing a traditional supply chain and a vendor managed inventory system (VMI) when a transportation disruption occurs between 2 echelons in a 5-echelon supply chain. The greatest impact occurs when transportation is disrupted between the tier 1 supplier and warehouse. In the traditional structure the retailer, warehouse, and tier 1 supplier experience the greatest inventory fluctuations and the highest goods in transit to their facilities. These impacts are less severe for the VMI structure, although unfilled orders are approximately the same for each.     

Impact of decision sequence on reliability enhancement with supply disruption risks

This paper considers a supply chain that consists of a manufacturer and a supplier who faces disruption risks. We investigate the impact of decision sequence on the supplier’s endogenous reliability enhancement and the firms’ equilibrium pricing strategies. The supply chain reliability achieves a higher level under the supplier–leader game, but this does not always lead to a higher payoff for the supply chain. Each firm prefers to make the decision first, while any decision sequence can become dominant for the supply chain. We also show that the supply chain can achieve coordination via the revenue sharing contract.     

Supplier hoarding,government intervention,and timing for post-disaster crop supply chain recovery

This work presents a multi-methodological approach to address the issue of post-disaster crop supply chain recovery under the influences of government intervention and supplier hoarding intention. A conceptual model which characterizes the antecedents of supplier hoarding intention is proposed, and validated using survey data. Grounded in the empirical study, an analytical model is then proposed for decision analysis of a two-tier crop supply chain recovering from post-disaster supply disruptions. Analytical results indicate that hoarding behavior reduces the time taken by supply chain members for supply recovery; and however, contributes to mixed effects on the expected profits of supply chain members.