From closed-loop to sustainable supply chains: the WEEE case

The primary objective of closed-loop supply chains (CLSC) is to improve the maximum economic benefit from end-of-use products. Nevertheless, the literature within this stream of research advocates that closing the loop also helps to mitigate the undesirable environmental footprint of supply chains. Therefore, closed-loop supply chains are assumed to be sustainable supply chains almost by definition. In this paper we analyse if and when this assumption holds. We illustrate our findings based on the Electric and Electronic Equipment (EEE) supply chain. For all phases of the supply chain, i.e. manufacturing, usage, transportation and end-of-life activities, we assess the magnitude of the environmental impacts, based on a single environmental metric, namely the Cumulative Energy Demand (CED). Given the environmental hot-spots in the Electric and Electronic Equipment supply chain, we propose useful extensions for existing CLSC optimisation models to ensure that closed-loop supply chains are at the same time sustainable supply chains.     

Nature inspired supply chain solutions: definitions,analogies, and future research directions

ABSTRACT

Supply chains are becoming increasingly complex, and many companies and researchers are looking to nature for finding solutions. In this paper, we provide a narrative synthesis and systematic review to explore state-of-the-art, and identify key areas for exploration of nature inspired solutions in the supply chain area. We consider strategic, tactical, and operational decisions within supply chains and identify analogies between biological systems and supply chains to create a new research agenda. Our findings show that the majority of the research in nature inspired supply chains from the systemic perspective focuses on closed loop supply chains. In contrast, similar systemic solutions such as industrial symbiosis, circular economy, and industrial ecology have not been explored as frequently. Reducing production waste (industrial symbiosis) in addition to end-of-life product waste (closed loop supply chains), optimising raw material use and extending the life of used resources (circular economy), investigating the interactions between biosphere and technosphere (industrial ecology), and seeking solutions to industrial problems from nature (biomimicry) are all possible paths for reaching a zero-waste economy. These systemic solutions have a considerable impact on the supply chains at the strategic, tactical, and operational levels, which need to be explored to identify efficient and effective solutions.     

分散式与集中式供应链演变路径研究

探讨了由生产商与零售商组成的两级供应链,分析链上成员之间的博弈从而构建两者的支付矩阵,通过计算雅可比矩阵,掌握供应链的演化稳定策略。通过参数分析与数值算例,详细讨论了参数变化对分散式与集中式供应链演化方向的影响,结果显示,供应链中决策受收益、成本等参数的影响显著。     

An entropy-based approach for measuring complexity in supply chains

Today's supply chains are more complex than ever due to globalisation and its effects, especially on logistics activities. Therefore, understanding and managing complexity in supply chains are very popular topics nowadays. Measures for complexity in supply chains contribute to their manageability and controllability. This paper describes an approach to the measurement of complexity in supply chains based on Shannon's information entropy. The new proposed approach gives a formal approach that is able to measure and analyse the supply chain complexity. The main contribution of this study is to extend two formulas (structural and operational complexity) building on Shannon's entropy measure to evaluate the complexity of a supply chain. The aim is to measure complexity associated with information and material flows in the chain. A numerical example is presented to demonstrate the approach.     

Channel coordination for multi-stage supply chains with revenue-sharing contracts under budget constraints

Real-life situations show that revenue-sharing (RS) contracts used in multi-stage supply chains have more complex structures than those that have been studied in recent research. In this paper, we study RS contracts in multi-stage supply chains where some members work with more than one upstream member. This general supply chain structure closely resembles those in actual practice under RS contracts. The literature on supply chain contracts has not adequately addressed contract design for supply chains with members who face budget constraints. We show that the RS contract could fail to coordinate supply chains when members are under particular budget constraints. In response, we propose a revenue-sharing with budget constraints (RSB) contract that adds no administrative cost. A properly designed RSB contract can be used to achieve supply chain coordination and to arbitrarily allocate profits in multi-stage supply chains. Our numerical results provide insights into ways supply chain coordination can be achieved under budget constraints through the RSB contract.     

A study on investments in the big data-driven supply chain,performance measures and organisational performance in Indian retail 4.0 context

The use of digital technologies such as ‘internet of things’ and ‘big data analytics’ have transformed the traditional retail supply chains into data-driven retail supply chains referred to as ‘Retail 4.0.’ These big data-driven retail supply chains have the advantage of providing superior products and services and enhance the customers shopping experience. The retailing industry in India is highly competitive and eager to transform into the environment of retail 4.0. The literature on big data in the supply chain has mainly focused on the applications in manufacturing industries and therefore needs to be further investigated on how the big data-driven retail supply chains influence the supply chain performance. Therefore, this study investigates how the retailing 4.0 context in India is influencing the existing supply chain performance measures and what effect it has on the organisational performance. The findings of the study provide valuable insights for retail supply chain practitioners on planning BDA investments. Based on a survey of 380 respondents selected from retail organisations in India, this study uses governance structure as the moderating variable. Implications for managers and future research possibilities are presented.     

集群式供应链大规模定制化的计划管理模式

以产业集群为平台的供应链(以下称为集群式供应链)有着基于同一产业的多单链性.多单链性和生产产品的同类性,使得集群式供应链具有进行大规模定制化生产的优势,为了实现这种优势,以时间竞争为出发点,通过中观相结合,分析了集群式供应链供应商、外包商、制造商和分销商的各环节计划管理,将集群式供应链的系统战略计划和各个企业运作计划进行有机整合起来,在此基础上给出了集群式供应链大规模定制化的主生产计划、物料需求计划和生产作业计划的分解机理.     

三级竞争供应链的渠道选择研究

在供应链链间竞争的背景下,研究三级竞争供应链的纳什均衡结构。利用非线性规划、纳什博弈和Stackelberg博弈理论,分析了2条三级竞争供应链的渠道选择问题,求解了3种情景：全分布式结构;全一体化结构和混合结构（一条供应链为一体化,另一条为分布式）下的决策变量的最优解,并分别依据3种决策标准,即制造商利润最大化、渠道利润最大化和供应链系统利润最大化,分析了不同决策标准下供应链纳什均衡结构。研究表明,三级竞争供应链的纳什均衡结构,依赖于产品之间的替代系数及决策标准,并且当供应链链间的竞争强度较大时,无论何种决策准则下,全分布式结构均为供应链的纳什均衡结构。     

Supply chain configuration with co-ordinated product,process and logistics decisions: an approach based on Petri nets

Supply chain configuration lends itself to be an effective means to deal with product differentiation and customisation throughout a supply chain network. It essentially entails the instantiation of a generic supply chain network to specific supply chains in accordance with diverse customer requirements. The lynchpin of supply chain configuration lies in the co-ordination of product, process and logistics decisions in relation to a variety of customer orders. This paper aims to provide modelling support to supply chain configuration. The ultimate goal is to assist companies to form appropriate supply chains with the most added-value to customer order fulfillment. A formalism based on coloured Petri nets is developed for configuring supply chains. System models are built upon the coloured Petri nets and used to incorporate product and process concerns into the supply chain configuration process. An industrial case study is reported to illustrate the potential of the coloured Petri net modelling formalism and the built system models for supply chain configuration.     

电子商务环境下我国农产品供应链体系的结构优化

首先回顾了我国农产品供应链体系的现状，其中包括现货市场供应链子体系、远期市场供应链子体系与期货市场供应链子体系。其次分析了当前我国农产品流通的主体——现货市场供应链体系的结构特性及其负面影响，并结合现实将农产品电子商务对供应链的改善作用总结为非中介化、再中介化、信息中介、垂直门户以及价值网五种不同的实现方式，最后提出了农产品供应链利用价值网实现优化的远景目标。     

A coordination theoretic model for three level supply chains using contracts

Typically, supply chain members are dependent on each other to manage various resources and information. The conflicting objectives and lack of coordination between supply chain members may often cause uncertainties in supply and demand. The basic elements of coordination theory like interdependency, coherency and mutuality may help in effective flow of information and material between the dependent supply chain members. Supply chain contract can be an effective coordination mechanism to motivate all the members to be a part of the entire supply chain. There are different types of supply chain contracts such as buy back and quantity flexibility contracts. Supply chain performance may be substantially improved by properly designing the contracts to share risks and rewards. The objective of this paper is to explore the applicability of coordination elements through an analytical model in three-level (Manufacturer-distributor-retailer) serial supply chains using contracts. The model evaluates the impact of supply chain contracts on various performance measures. The impact of some contract may be on some specific performance measure only, which helps managers to choose the type of contract if there is an objective of improving certain performance measure before hand. In three-level supply chains, the contracts are designed at two distinct interfaces: Manufacturer-distributor and distributor-retailer. The model demonstrates the complexity in evaluating the decision variables of three level supply chains. The proposed model is a novel approach to apply coordination theory at various levels of supply chain. The model also presents how the coordination elements are related to each other in various coordination cases.     

The impact of collaborative transportation management on demand disruption of manufacturing supply chains

This paper describes the impact of collaborative transportation management (CTM) on the performance of manufacturing supply chains using a multi-agent approach. Two supply chain models (with and without CTM) are proposed to show how it realises the real operational interactions between different supply chain partners under demand disruption. Simulation results of the proposed models reveal the evolution of the CTM supply chain with demand disruption. The dynamic delivery ability and order point which are caused by demand disruption in the CTM supply chain are investigated. The results indicate that CTM can significantly reduce costs and improve the flexibility of companies in handling demand disruption problems. It is suggested that CTM is an efficient mechanism to manage supply chains, especially under a demand disruption environment.     

Modelling customer and technical requirements for sustainable supply chain planning

Sustainable supply chains are the need of modern times. In order to make them successful, listening to voice of the customer and integrating them in the design and development phases of supply chains are very important. In this paper, we propose a technique called sustainability function deployment (SFD) developed on the concept of quality function deployment (QFD) to model customer and technical requirements, establish relationship between them and prioritise them for developing sustainable supply chains. SFD gathers customer and technical requirements for sustainable supply chain planning using C-REQ and T-REQ surveys, generates priority of customer requirements using Priority Matrix, performs screening of technical requirements using gap analysis, and generates requirements weights using QFD, thereby providing a structured approach to the decision-makers to select the right areas of improvement. Both the customer and technical requirements are captured from a socio-economic-environmental perspective. Results of application of the proposed technique are provided. The strength of the proposed approach is its novelty in integration of priority matrix and gap analysis in prioritising requirements based on their importance and performance in SFD. Besides, SFD facilitates modelling of complex, interrelated requirements in sustainable supply chain planning.     

Equilibrium analysis of distribution channel structures under power imbalance and asymmetric information

This paper investigates the problem of channel choice game in two power-imbalanced supply chains consisting of the leader supply chain and the follower supply chain. We assume that there exists symmetric and asymmetric cost information between the two supply chains, and that the two chains as well as the two members in each chain follow the Stackelberg game setting. We analyse four competition scenarios: both chains are decentralised, where individual members of both supply chains maximise their own profits by independently selecting their price policies; both chains are integrated, where manufacturers and retailers coordinate their decisions to maximise supply chain profits; the leader chain is decentralised and the follower integrated; the leader is integrated and the follower decentralised. The primary objective of this paper is to investigate the influence of power imbalance, information asymmetries, and the degree of product substitutability under channel choice equilibrium. We find that, in contrast to earlier literature where all manufacturers share equal or balanced decision-making power, an integrated distribution channel is the dominant strategy for the leader under symmetric and asymmetric information Stackelberg game. As the degree of product substitutability increases, the follower will gradually switch from integrated distribution channel to decentralised distribution channel; the follower can gain from constructing a decentralised distribution channel as the prediction accuracy of the leader increases.     

Pricing and ordering decisions of two competing supply chains with different composite policies: a Stackelberg game-theoretic approach

In today’s global highly competitive markets, competition happens among supply chains instead of companies, as the members of supply chains. So, the partners of the chains seek to apply efficient coordinating strategies like discount, return, refund, buyback, or the other coordinating policies to abate the operation costs of the chains and subsequently increase market shares. Hence, because of the importance and application of these strategies in the current non-exclusive markets, in this study, we introduce different composite coordinating strategies to enhance the coordination of the supply chains. Here, we consider two competing supply chains where both chains launch the same product under different brands to the market by applying different composite coordinating strategies. Each supply chain comprises one manufacturer and a group of non-competing retailers where the manufacturer receives raw materials from an outside supplier and transforms them into a finished product; then, the products are sold to the retailers to satisfy the demands of market. In the first chain, a composite (QFF) policy, which is the combination of quantity and freight discount, as well as free shipping quantity policies, are considered between upstream and downstream members while in the second one, different composite polices are considered between upstream and downstream members such that the supplier offers a composite policy, as the first chain, to the manufacturer and the manufacturer proposes a composite (QPR) policy, which is the combination of quantity discount and partial-refund customer return policies, to the retailers. The main objective of the paper is to determine the optimal selling prices and the order quantities of the manufacturer and the retailers in each chain in presence of different composite coordinating strategies. A Stackelberg game-theoretic approach is employed between the members of each chain where the manufacturer is a follower and the retailers are leaders. The concavity of profit functions is proved. Finally, the applicability of the models is justified by presented numerical examples. Moreover, the effects of these strategies on the decisions of the chains’ partners are examined.     

A review of coordination studies in the context of supply chain dynamics

Supply chain management is and has been a popular research topic in recent years. Among the reported studies, coordination is an important ingredient to improve the performance of supply chains subject to the presence of system dynamics. This paper sets out to review some recent supply chain studies in the last decades that are related to coordination among supply chain members regarding supply chain dynamics. Focus is put on inventory management problems. More than a hundred research papers are reviewed and they are broadly categorised into analytical approaches and simulations approaches. They are further divided into sub-categorises. Observations of each category are summarised in this paper so that characteristics of each of which could be comprehended. In addition, the concluding section reveals some insights that could be considered for future research regarding coordination in supply chains and supply chain systems dynamics.     

Arcs of supply chain integration

Integration is posited by many authors as a supply chain utopia. Indeed, it is claimed as being synonymous with supply chain management excellence. The primary aim of this research is to verify the link between supply chain integration and competitive performance. Detailed information collected via an 8-year international field study of 50 products and their associated supply chains subjected to an extensive statistical analysis provides rigorous insight into supply chain integration in practice. The breadth of supply chain integration significantly correlates with increased performance, yet in practice, the majority of supply chains are not well integrated. However, most supply chains seem to follow a popular route when seeking to enable seamless operations. This starts with enhanced internal effectiveness followed by upstream streamlining and then finally downstream integration. If practitioners are still struggling with supply chain integration, this research confirms that they are not unique in their predicament. Indifferent practice is indeed the norm. Fortunately, practitioners can follow the popular route established herein when seeking to improve integrative capability.     

A survey of semiconductor supply chain models Part II: demand planning,inventory management,and capacity planning

Part I of this three-part series described semiconductor supply chains from the decision-making and functional perspectives, using this as a framework to review the industrial engineering and operations research literature on the problems arising in these supply chains. Part I then reviewed the literature on Strategic Network Design, supply chain coordination, sustainability and simulation-based decision support. This paper, Part II, reviews the areas of Demand Planning, Inventory Management and Capacity Planning in semiconductor supply chains. Part III concludes the series by discussing models to support Master Planning, Production Planning and Demand Fulfilment in this industry.     

Selection of risk mitigation strategy in electronic supply chains using grey theory and digraph-matrix approaches

Supply chains are becoming more lengthy and complex due to globalisation and vertical integrations. In this context, adopting proactive approaches is needed for dealing with changing risks and vulnerabilities for securing supply chain systems. Supply chain risks are interlinked and thus, one mitigation strategy can reduce many of other supply chain risks. For example, aggregate or pooling demand reduces forecast risks, capacity risks and inventory risks. Also, some of the risk mitigation strategies have negative influences over certain supply chain risks as adding capacity has a negative influence on capacity risks. Twelve major supply chain risk categories and 21 risk mitigation strategies with typical focus on electronics manufacturing supply chains have been identified. A combination of grey theory and digraph-matrix methodologies has been used for quantifying various supply chain risk mitigation strategies and this approach is not seen in literature till date. The proposed model was also tested taking a case study of an Indian electronics manufacturing company. Obtained results were also subject to sensitivity analysis. The net positive influence values of risk mitigation strategies proposed in this research could effectively be used by top management for ascertaining their risk mitigation strategies for better management of supply chains as a whole.     

Information sharing and coordination mechanisms for managing uncertainty in supply chains: a simulation study

The study aims to investigate the effectiveness of information sharing and coordination mechanisms in reducing uncertainty. Supply chains are constantly subject to unpredictable events that can adversely influence its ability to achieve performance objectives. This paper primarily aims at managing uncertainties originating from unexpectedly large demand spikes. The supply chain literature is full of effective supply chain uncertainty management practices. This paper reviews the different practices for improving management of uncertainty and proposes several combinations of information sharing and coordination mechanism for reducing the uncertainty in supply chains. Next, the proposed combinations are tested on the make-to-stock supply chain of a paper tissue manufacturer using an agent-based simulation approach to show how the use of different levels of information sharing and coordination can be effective in managing uncertainty under daily operations facing a huge mismatch of actual and forecast demand. The findings of this research suggest that, a centralised information structure without widespread distribution of information and coordination is not effective in managing uncertainty of supply chain networks, even with increased frequency of information flow. Similarly, coordinating material flows without widespread information sharing does not improve supply chain uncertainty management. Central coordination of material flows with supply chain wide information sharing across different members is found to be essential in managing supply chains effectively under uncertainty.