A STUDY ON VIRTUAL ENTERPRISE COALITION WITH MULTI-AGENT TECHNOLOGY IN AGILE MANUFACTURING ENVIRONMENT

There is a growing recognition that current manufacturing enterprises must be agile, that is, capable of operating profitably in a competitive environment of continuously changing customer demands. The use of a virtual enterprise (VE) is becoming increasingly prevalent, and that has been made possible, in part, due to the significant advances in communication and information technology in recent years. A manufacturing system is one of the competitive factors that forms an effective VE. Therefore, for manufacturers wishing to obtain a contract in VE, it is crucial to present attractive and competitive offers to other coalition members. There are several criteria to these offers, such as cycle time, fulfilment of due date or quick shipping date, cost, and quality assurance for the ordered products. Manufacturing system simulation could endorse the basic estimates of the criteria for the strategic offer. The distributed simulation model concept provides practical solutions to facilitate such a large-scaled precise simulation model in the VE environment, because it is constructed as the integration of several manufacturing simulation models of each production module in the factory. As a solution to realize this integration, we propose a Distributed Virtual Factory (DVF) concept that consists of distributed precise simulation models connected by several synchronization mechanisms named Time Bucket algorithms. A DVF enables precise evaluations of the whole manufacturing system, especially in terms of the material flows. In this study, we introduce an Activity Based Costing (ABC) method into the DVF architecture to estimate the detailed cost analysis of the products. The methodology facilitates strategic enterprise management to prepare the request for the bids in the VE environment. The effectiveness of the proposed concept in agile manufacturing is discussed with simulation experiments.

Virtual Enterprise (VE) is a temporary alliance of enterprises that come together in order to better respond to cope with demand of customers. VE includes many kinds of business models in term of supply chain, such as vertical structure, horizontal structure and so on. In this study, we focus on the negotiation process in VE, and try to apply multi-agent paradigm with marketing science and game theoretic approach as its decision making mechanism in order to analyse the characteristics of several business models. We propose VE simulation models to analyse the forming dynamism of VE amongst several potential members in the negotiation domain, and finally clarify the performance of VE based business models.

The impact of alignment between virtual enterprise and information technology on business performance in an agile manufacturing environment

Nowadays, virtual enterprise (VE) is an important paradigm of business management in an agile environment. VE exists in several kinds of business organization through multi-layered product flows. It is obvious that a mechanism, through which these different enterprises can be integrated together, is required for the better management of VE. In this paper, we focus on the negotiation process in VE formulation as a basic research to clarify its effective management. Each enterprise in VE is defined as a software agent with multi-utilities, and three types of primitive business models are targeted, such as the vertically integrated business model, horizontally specialized business model and hybrid business model. We develop a three-layered VE model for computer simulation so as to clarify VE formulation dynamism with the proposed negotiation mechanism.

Agile manufacturing, a recently popularized concept, has been advocated as the 21st century manufacturing paradigm. Markets become highly diversified and global, and continuous and unexpected change, become the key factors for success. The need for a method of rapidly and cost­ effectively developing products, production facilities, and supporting information technology has led to the concept of agile manufacturing. Agile manufacturing requires enriching of the customer, cooperating with competitor organizing to manage change, uncertainty and complexity; and leverage people and information. The key enabler of agile manufacturing include: i) virtual enterprises formation, ii) physically distributed teams, iii) integrated business information system. This framework as a basis for understanding the major strategies and relevant tecnnologies of agile manufacturing (AM).

Design of distributed information systems for agile manufacturing virtual enterprises using CORBA and STEP standards

This paper offers a service-oriented architecture (SOA) for ontology-based multi-agent system (MAS) negotiations in the context of virtual enterprises (VEs). The objective of this paper is fourfold. First, it is to design a SOA which utilizes ontology and MAS to provide a distributed and interoperable environment for automated negotiations in VE. In this architecture, individual ontologies for both the VE initiator and its potential partners are constructed to describe and store resources and service knowledge. Second, a series of semantic ontology matching methods are developed to reach agents' interoperability during the negotiation process. Third, correspondence-based extended contract net protocol is presented, which provides basic guidelines for agents' reaching mutual understandings and service negotiation. Last, a fuzzy set theory based knowledge reuse approach is proposed to evaluate the current negotiation behaviors of the VE partners. A walkthrough example is presented to illustrate the methodologies and system architecture proposed in this paper.

New advancements in computers and information technologies have yielded novel ideas to create more effective virtual collaboration platforms for multiple enterprises. Virtual enterprise (VE) is a collaboration model between multiple independent business partners in a value chain and is particularly suited to small and medium-sized enterprises (SMEs). The most challenging problem in implementing VE systems is ineffcient and inflexible data storage and management techniques for VE systems. In this research, an ontology-based multi-agent virtual enterprise (OMAVE) system is proposed to help SMEs shift from the classical trend of manufacturing part pieces to producing high-value-added, high-tech, innovative products. OMAVE targets improvement in the flexibility of VE business processes in order to enhance integration with available enterprise resource planning (ERP) systems. The architecture of OMAVE supports the requisite flexibility and enhances the reusability of the data and knowledge created in a VE system. In this article, a detailed description of system features along with the rule-based reasoning and decision support capabilities of OMAVE system are presented. To test and verify the functionality and operation of this system, a sample product was manufactured using OMAVE applications and tools with the contribution of three SMEs.

Virtual Enterprise (VE) is one of the growing trends in agile manufacturing concepts. Under this platform companies with different skills and core competences are cooperate with each other in order to accomplish a manufacturing goal. Success of VE, as a consortium, highly depends on the success of its partners. So it is very important to choose the most appropriate companies to enroll in VE. In this study a Fuzzy Inference System (FIS) based approach is developed to evaluate and select the potential enterprises. The evaluation is conducted based on four main criteria; unit price, delivery time, quality and past performance. These criteria are considered as inputs of FIS and specific membership functions are designed for each. By applying fuzzy rules the output of the model, partnership chance, is calculated. In the end, the trustworthy of the model is tested and verified by comparing it with fuzzy-TOPSIS technique providing a sample.

Lean and agile manufacturing for work-in-process (WIP) control

In an efficient Virtual Enterprise (VE), where all the partners, both sending and receiving messages have to lead to acceptable and meaningful agreements, it is necessary to have common standards (an interaction protocol to achieve deals, a language for describing the messages’ content and ontology for describing the domain’s knowledge). This paper introduces first the ForEV platform, implemented through a Multi-Agent System. This platform facilitates partners’ selection automatic process in the context of VE and includes a negotiation protocol through multi-criteria and distributed constraint formalisms, as well as a reinforcement learning algorithm. Then, Ontology-based Services are proposed to be integrated in ForEV architecture in order to help in the VE formation process. These services will make the platform more open, enabling the establishment of the negotiation process between agents with different ontologies although representing the same domain of knowledge. An Ontology-based Services Agent is the responsible for providing the Ontology-based Services and monitoring the whole agents interaction just in time, without needing of a previous and tedious complete ontology mapping process. In our architecture each agent (either market or enterprise) has its own architecture and functionalities (some developer will design and build the ontology with some tool and, later, the agent will access the generated file/database), which implies the heterogeneity of the all Multi-Agent System.

Partner selection is one of the most critical issue in virtual enterprise, which has been extensively researched in recent years. It is difficult to be solved by the traditional optimization methods for partner selection is a combinatorial optimization problem. In this paper, an improved quantum swarm evolutionary algorithm based on time-varying acceleration coefficients (IQSEA_TVAC) is proposed for partner selection optimization problem. The results of simulation experiments show that the improved algorithm is valid and outperforms the conventional quantum evolutionary algorithm.

The simulation based on the Multi-Agent plays an important role in the research of economics. This paper formulates the game theory model of information sharing in virtual enterprise. Using the computer simulation technology of Multi-Agent, we study the causes of difficulty in forming and maintaining the cooperation of information sharing in virtual enterprise. The results show that the sharing costs, the punitive coefficient and the initial rate of cooperation are the factors influencing the level of cooperation in information sharing. At last, we put forward the corresponding measures of enhancing the level of cooperation.

Notice of Violation of IEEE Publication Principles<br><br>"Knowledge Discovery from Virtual Enterprise Model Based on Semantic Annotation,"<br>by Chengzhu Sun, Xiaofei Xu, Xiangyang Li, Shengchun Deng,<br>in the Proceedings of the Fifth International Conference on Fuzzy Systems and Knowledge Discovery, 2008. FSKD '08, vol.5, pp.546-551, Oct. 2008<br><br>After careful and considered review of the content and authorship of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE's Publication Principles.<br><br>This paper contains significant portions of original text from the paper cited below. The original text was copied without attribution (including appropriate references to the original author(s) and/or paper title) and without permission.<br><br>"A Controlled Language for Semantic Annotation and Interoperability in e-Business Applications"<br>by M.Missikoff, F.Schiappelli , F.Taglino<br>in the Proceedings of the Semantic Integration Workshop, collocated with the Second International Semantic Web Conference (ISWC-03), October 2003<br><br> <br/> Discovering knowledge from virtual enterprise model is becoming increasingly important, as numerical models established for virtual enterprise are difficult to support interoperability of virtual enterprise. To solve this problem, a knowledge discovery method based on semantic annotation is put forward in this paper. A graphic ontology representation schema for virtual enterprise model is described, which is called ontology structure graph (OSG). Based on applications of semantic annotation, the process of knowledge discovery in the virtual enterprise model base is given and activities such as model selection, semantic annotation, data transformation, knowledge extraction and ontology interoperation in knowledge discovery process are illustrated in detail. Then, several critical issues influencing knowledge discovery are explained, including the organization of domain vocabulary, the definition of semantic annotation rules and semantic affinity function, the formulation of reference ontology. Finally, an instance is given to demonstrate the knowledge discovery method and results of knowledge discovery are presented.

Development of a dynamic data interchange scheme to support product design in agile manufacturing