A hybrid multi-agent negotiation protocol supporting supplier selection for multiple products with synergy effect

Supplier selection is an important problem in supply chain management. In practice, it is common for a purchasing company to procure a bundle of products simultaneously. In this regard, synergy effect could exist between products and hence affect the final choice of suppliers. It is therefore necessary to incorporate the synergy effect between products in supplier selection process. Agent-based negotiation models are applied to automate supplier selection process. Negotiation protocol is an essential component should be considered when building an effective agent negotiation model. The objective of this research is to propose a negotiation protocol special for multi-product supplier selection problem. The negotiation protocol is a hybrid multi-agent protocol of combinatorial procurement auction protocol and multi-bilateral bargaining protocol. The negotiation protocol is able to support the purchasing company and suppliers negotiate on the concrete commitments of multiple products simultaneously, and select suppliers for multiple products. In addition, both the purchasing company and suppliers can express their preferences on the synergy effect between products in negotiation process by adopting the negotiation protocol. Simulation is conducted to demonstrate the effectiveness and efficiency of the negotiation protocol.     

Quantity discount coordination for allocation of purchase orders in supply chains with multiple suppliers

Studies about supply chain coordination have emphasised maximising the profit of the overall supply chain, but the profit changes of individual members in the supply chain have often been overlooked. It has been shown that profit increment of the whole supply chain may not be beneficial for every individual member. Therefore, the use of quantity discounts to achieve the coordination of a supply chain is discussed in this article. A two-echelon selling system with a single buyer and multiple suppliers is considered to enhance profitability for both sides at the same time. An acceptable quantity discount condition for both the buyer and the suppliers to determine an appropriate order quantity allocation to produce more profits in the supply chain is proposed. Furthermore, the profit distribution between the buyer and each supplier is studied. Finally, the results of the numerical application show that the buyer should focus on managing the procurement costs to decrease the acquiring costs, and the suppliers should focus on the fixed costs of management to reduce the production costs in machine operations.     

Buyer behaviours and the performance of the supply chain: An international exploration

This paper studies the effects of buyer?supplier interaction in a supply chain environment. It focuses on the effects of buyer behaviours (such as supplier selection, number of suppliers, percentage of outsourcing, and frequency of production changes) on the performance of the supply chain. Using data collected from machine tool manufacturers around the world, the various behaviours of buyers are examined to see how they induce or mitigate the degree of uncertainty experienced by suppliers and thus affect suppliers' delivery performance. In addition, it was investigated how such buyer behaviours could further affect the supply chain's ability to perform as expected. The statistical results suggest that many buyer behaviours that have no direct effect on buyer's performance can have a significant effect on their suppliers' performance. Specifically, buyer behaviours directly manifest in supplier performance and only indirectly manifest in their own performance. This can give the buyer the false impression that the supply base is harming performance, when the real problem is the way the buyer manages the supply chain. The results vary by region of the world, suggesting that any theory that links buyer behaviours to supplier performance will need to consider a firm location.     

A multi-agent model for the reasoning of uncertainty information in supply chains

In order to simulate the real world effectively, this paper proposes a multi-agent model that integrates a price negotiation support system based on the use of intelligent agents capable of processing information uncertainty. The certainty factor is integrated in expert systems to support the decision of agents. In the model, each agent is integrated with an expert system to deal with the uncertainty information. A real example of supply chains is chosen to show the validity of the proposed multi-agent model. Virtual companies can use the uncertainty information to support decisions. Multiple experiments are conducted to work on the coordination of the supply chain. The selling and purchasing prices in the supply chain are proposed in the experimental results. These prices are similar with the data in a real supply chain and are the optimal price strategy for the supply chain. The model was programmed using Jess and Swarm, which was run on Windows XP. The multi-agent model in the paper is beneficial to the reasoning of uncertainty information in multi-agent systems.     

基于MAS的敏捷供应链谈判模型

通过分析敏捷供应链的业务流程,建立了一个多Agent的敏捷供应链的谈判模型,并将敏捷供应链双边谈判中买卖双方表示成两个谈判Agent.任选其中买方谈判Agent的状态转换过程抽象为动作规划,并把它形式化为一个模糊自动机.在分析了Agent谈判的过程之后给出了谈判Agent的体系结构,并给出了该谈判模型的应用案例,为建立实用的Agent谈判系统奠定了理论依据.     

Coordinating a three-level supply chain with quantity discounts

Numerous examples exist that illustrate how companies enjoying a strong position in a supply chain unilaterally dictate terms to their suppliers and/or their customers. This paper suggests a mechanism by which a company can coordinate its purchasing and production functions and create an integrated plan that dictates order and production quantities throughout a three-firm channel. Specifically, we model a company that attempts to dictate channel lot sizes by obtaining a quantity discount from its supplier while offering perhaps a different one to its customer. Previous quantity discount research has examined supply chains consisting of only two levels, a seller and a buyer. This paper considers a three-level chain (supplier–manufacturer–retailer) and explores the benefits of using quantity discounts on both ends of the supply chain to decrease costs. We show that incorporating quantity discounts into both ends of the supply chain can significantly decrease costs compared to concentrating only on the lower end. Furthermore, the results of the decentralized procedure described here are robust vis-à-vis a centralized decision-making procedure.     

Supplier credit guarantee loan in supply chain with financial constraint and bargaining

This paper adopts a multiunit bilateral bargaining framework on financial decision. In a two-echelon supply chain, the supplier sells products through a financial constraint retailer. If needed, the retailer gets a short-term financing from a bank by supplier credit guarantee loan (CGL). Through applying the Nash bargaining framework, we formulate two-level game models, i.e. Retailer-Supply System negotiation and Supplier-Bank negotiation. In this paper, we study and discuss the equilibrium order quantity which is affected by initial working capital and interest rate, the retailer-supply system negotiation and upstream wholesale price effects for supply chain performance, the supplier-bank negotiation and interest rate decisions with different capital markets. The results show: (i) there exists loan size limit for financial constraint retailer under CGL. (ii) The upstream wholesale price increase will weaken retailer’s bargaining position, and the supply system may gain or lose depending on the bargaining power. (iii) There exists unique equilibrium sharing ratio in supply system, which means CGL can achieve risk sharing. (iv) Within a supply system, the upstream wholesale price advantage will weaken bank’s profit, whereas supplier may gain or lose depending on his bargaining power.     

MANPro: mobile agent-based negotiation process for distributed intelligent manufacturing

This paper examines negotiation procedures in an agent-based distributed shop floor control system (SFCS). A distributed SFCS is under a heterogeneous environment, which is controlled through negotiations between autonomous agents. The negotiation-based control can be considered as the core of a distributed control paradigm. An efficient information exchanging mechanism and an information model with reasonable structure are indispensable for effective negotiations. This paper proposes a novel negotiation mechanism, called a mobile agent-based negotiation process (MANPro), which applies a mobile agent system to the process of information exchange. Since using mobile agents allows each component to execute asynchronously and autonomously and to adapt dynamically to the execution environment, MANPro may guarantee autonomy of agents. Moreover, it is possible to build a fully distributed and autonomous SFCS by using MANPro. MANPro is based on the agent-based control architecture, which includes a communication architecture and an information architecture. The communication architecture provides the exchanging mechanism of information, defining functional modules to support the mechanism while the information architecture provides the framework for information modelling on negotiation, proposing information models required for introducing the ontology concept.     

Developing environmental and social performance: the role of suppliers’ sustainability and buyer–supplier trust

We explore how environmental and social performance of manufacturing firms can be improved as sustainable supply chain management (SSCM) develops and evolves within a firm from internal to external practices. Importantly, this study considers how key suppliers’ sustainability performance and buyer–supplier trust mediate and moderate such a development. A conceptual framework is developed which relies on resource-based theories and emerging empirical evidence. Then, partial least square methodology is applied on survey data from a sample of Italian manufacturing firms. Results show that manufacturing firms’ sustainability performance improves as SSCM develops; however, while internal practices have a direct impact on performance, the effect of external practices on a manufacturing firm’s sustainability performance is fully mediated by key suppliers’ sustainability performance. Yet, buyer–supplier trust significantly influences the scope of such gains. Since evidence suggests that manufacturing firms are still struggling with how to leverage supply chain innovation potential for sustainable development, this study provides a timely and valuable contribution.     

Interdependent order allocation in the two-echelon competitive and cooperative supply chain

In this paper, we consider an order allocation problem in a two-echelon supply chain with multiple suppliers and multiple demanders. The orders from the demanders are interdependent in terms of execution sequence. We consider both the competition and cooperation relationships between the suppliers and demanders. We provide formal definition for the order allocation problem and propose a negotiation mechanism which includes a two-stage negotiation protocol and two heuristic negotiation algorithms. Different negotiation strategies are proposed for the demanders and suppliers to resolve the order interdependency and competition conflict. An automated negotiation approach is introduced to implement the negotiation mechanism. The computational experiments show that orders under different supply chain contexts can be allocated with high success rate. We also numerically compare the influence of different negotiation strategies and investigate the interaction of conflict resolutions.     

动态供应链谈判代理的设计及实现

面向动态供应链,引入智能代理技术,充分发挥智能多代理系统的自主性,重点就商业谈判体系以及其功能的设计与实现进行了较为深入的研究.根据业务交易的典型阶段,建立了业务谈判的多代理软件体系,给出了相应的谈判词汇表的描述.确立了谈判规则,并以DFA为工具描述谈判过程,进而实现了一个自主谈判过程.     

A multi-attribute multi-item negotiation mechanism of supply chain networks between buyers and sellers

This article focuses on the multi-attribute multi-item negotiation between multiple manufacturer agents (MAs) and multiple material supplier agents (MSAs). A coalition formation-based negotiation protocol is proposed. The MSAs are allowed to establish coalitions when the orders of the MAs exceed their abilities. Three attributes (price, quantity and lead time) of the items are considered during the negotiation. Both the MAs and the MSAs can give concessions among the attributes in tradeoff relationships according to their own preferences. The non-cooperative game is introduced to find the equilibria of the negotiations. The final allocation scheme is determined to maximise the total profit of the supply chain networks based on the equilibria. Simulations are provided to verify the effectiveness and feasibility of the proposed protocol.     

Monitoring type B buyer–supplier relationships

The ability to monitor supplier performance is a critical capability for maintaining strong buyer–supplier relationships. Monitoring type B suppliers is especially challenging as they are not as clearly defined as either type A, with strong strategic partnerships, or type C, with little partnership. This research develops a non-parametric multivariate Hoteling’s T ² control chart to capture the in-control state of a dyadic relationship (Phase I), and show how it would be developed based on survey data of buyer–supplier relationship attributes. Modelling the satisfactory level of dyadic relationship performance is very useful for identifying when the relationship begins to move away from the desired state. We then use the designed control chart to monitor the relationship between dyads over time to determine if any unusual behaviour has occurred (Phase II) and illustrate its implementation through a case study from the auto industry. This research illustrates how supply chain managers can secure and improve their supply chain performance by monitoring and maintaining strong relationships with their partners. The proposed method extends the existing SPC tools to effectively manage Type B buyer–supplier relationships.     

Collaboration in humanitarian supply chains: an organisational culture framework

The purpose of this study was to determine the impact that institutional logics and, more specifically, organisational culture can have on humanitarian supply chain (HSC) collaboration. A framework was developed that explicates buyer–supplier collaboration in a humanitarian setting. Twenty-nine semi-structured interviews were conducted with buyers and suppliers. The data indicated that in a HSC, collaborative outcomes, such as new product development, inventory management, and product/service delivery, are influenced by the buyers’ and suppliers’ organisational cultures. Based on suppliers’ characteristics, they can be classified as humanitarian suppliers, commercial suppliers, and humanitarian and commercial suppliers. These groups have distinct organisational cultures. An unexpected finding is that suppliers that serve commercial buyers primarily claim to have encountered no issues in supply chain collaboration with humanitarian buyers, although they have different types of organisational cultures. The factors that lead to successful collaboration are identified as trust, commitment, information sharing and mutual respect. Simultaneously, dominant institutional logics are observed in the dyadic relationship.     

基于供应链整体利益最大化的企业订货策略研究

经典的经济订货模型(EOQ)仅仅从买方的角度来考虑订货过程中的成本最小化问题。本文从企业和供应商这一供应链系统的整体利益角度,综合考虑了双方在订货中的储存和订货等费用来研究最优订货策略;在订货实务中,还对供应链整体的单位存储费用进行了变通处理。通过订货实例,分析了这种订货策略对买卖双方以及整体利益的影响。     

激励供应商R&D努力的最优补贴策略研究

构建了一个由两个竞争的供应商、一个采购商和最终消费者组成的供应链模型,采购商通过招标方式向供应商采购物品,供应商的R&D活动可以降低自己的制造成本.分别考虑了对供应商总额补贴、对供应商单位补贴和对消费者单位补贴三种不同情形下,政府R&D补贴对供应商的R&D努力和社会福利的影响.研究发现,对供应商的总额补贴并不能激励供应...     

Dynamic optimisation for highly agile supply chains in e-procurement context

In the conditions of an increased worldwide competition, supply chains are struggling to respond to an increasingly volatile and complex environment. With technological advances, current practices to build efficient supply chains have changed. Companies are seeking to use internet in order to cope with the flexible and dynamic nature of logistics networks. The purpose of this article is to address the flexible dynamic e-procurement context under asynchronous and repetitive variations over time. The supply chain considered is composed of two levels (buyer–suppliers) operating in highly agile environment. The questions facing the buyer is how many units of product should be purchased and from which supplier in response to variation in term of price and capacity. Because of this highly changing environment characterised by frequent changes in a short time, most of the classical optimisation approaches seem inadequate to address these problems. Recently, dynamic optimisation has been proposed to deal with such problems. However, we have no knowledge of its application in a supply chain context. We suggest a dynamic genetic approach which is applied to an e-procurement context in aim to optimise the procurement process during time.     

生态供应链保鲜努力成本分担契约研究

在生鲜产品的需求受产品新鲜度和价格影响的情况下,论文考虑供应商的保鲜努力水平和运输产品所需时间对产品新鲜度的共同影响,分别构建了集中式和分散式供应链决策模型,并对最优保鲜努力水平、产品销售价格和供应链利润等进行了求解;利用传统成本分担契约和纳什讨价还价下成本分担契约对供应链进行协调,并结合算例对相关参数进行了灵敏度分析。研究表明,两种成本分担契约可以促使供应商提高保鲜努力水平,并为供应链带来更高的利润,其中纳什讨价还价下的成本共担契约更为有效。     

A multi-agent system for chemical supply chain simulation and management support

Modern chemical production is customer-driven and the desired delivery time for the products is often shorter than their campaign length. In addition, the raw materials supplying time is often long. These features make it desirable to provide tools to support collaborative supply chain decision making, preferably over the Internet, and where there are conflicts, compromise decisions can be quickly reached and the effects of the decisions can be quantitatively simulated. This paper des cribes such a multi-agent system (MAS) that can be used to simulate the dynamic behaviour and support the management of chemical supply chains over the Internet. Geographically distributed retailers, logistics, warehouses, plants and raw material suppliers are modelled as an open and re-configurable network of co-operative agents, each performing one or more supply chain functions. Communication between agents is made through the common agent communication language KQML (knowledge query message language). A t the simulation layer, the MAS allows distributed simulation of the chain behaviour dynamically, so that compromise decisions can be rapidly and quantitatively evaluated. Because in a chemical supply chain the scheduling of the plant often dominates the chain performance, an optimum scheduling system for batch plants is integrated into the MAS. The functions of the system are illustrated by reference to a case study for the supply and manufacture using a multi-purpose batch plant of paints and coatings.