Heterogeneous Manufacturing Research Articles

Structural estimation and solution of international trade models with heterogeneous firms

We present an empirical implementation of a general-equilibrium model of international trade with heterogeneous manufacturing firms. The theory underlying our model is consistent with Melitz (2003). A nonlinear structural estimation procedure identifies a set of core parameters and unobserved firm-level trade frictions that best fit the geographic pattern of trade. Our estimation model is consistent with the specified general equilibrium model, and we conduct general equilibrium counterfactual analyses to illustrate model responses. We first assess the economic effects of reductions in measured tariffs. Taking the simple-average welfare change across regions the Melitz structure indicates welfare gains from liberalization that are four times larger than in a standard trade policy simulation. Furthermore, when we compare the economic impact of tariff reductions with reductions in estimated fixed trade costs we find that policy measures affecting the fixed costs are of greater importance than tariff barriers.

Semantic Web Service Based Framework for Inter-Organizational Business Process Management

To support business and engineering collaboration in the diversified and global markets, enterprises are trying hard to continuously align their actual business processes to response customers’ demands. In this context, a flexible framework for inter-organizational process management is proposed, in which ontologies and semantic web service technologies are used throughout process modeling, implementation and execution. Heterogeneous manufacturing resources are encapsulated as uniform semantic web services, called manufacturing services, which are published, located and combined into executable processes. By means of formally definition of service capacity and as the mediation, business logic and implementation techniques is loosely coupling relationship, so enterprises can collaborate without prior relationship established and adjust their processes on demand.

Manufacturing Service Integration Architecture for Networked Manufacturing

Intense competition drives the need for dynamic integration of dispersed and heterogeneous manufacturing services. This paper proposes a kind of semantic-based service integration architecture for networked manufacturing. A unique property of this architecture is that it provides the unified interface encapsulation approach and semantic analyzing method to realize dynamic and loose coupling integration. Some key technologies are introduced to demonstrate how the proposed integration architecture can be used to establish a collaborative environment, wherein manufacturing services are semantic modeled, semantic analyzed, and dynamically integrated on-demand.

An approach to manufacturing grid resource service scheduling based on trust-QoS

Manufacturing grid (MGrid) aims to solve the problem of distributed and heterogeneous manufacturing resource sharing and collaborative operation. Compared with traditional scheduling methods in distributed computing system such as computing grid, which emphasises execution time, the resource service scheduling in MGrid emphasises the manufacturing ability sharing, and requires higher resource service ability and reliability, therefore demands higher trust in MGrid resource service scheduling. In this paper, the measurement and evaluation models of trust-QoS in MGrid are proposed. A trust-QoS based MGrid resource service scheduling framework is proposed, followed by the scheduling algorithms. Simulation and algorithms performance comparison show that the proposed methods are sound on success rate and execution efficiency.

Study of failure detection and recovery in manufacturing grid resource service scheduling

A Manufacturing Grid (MGrid) system is different from a conventional distributed computing system due to its focus on larger-scale, distributed and heterogeneous manufacturing resource and service sharing, including equipment resources, application system resources, material resources, technical resources, public service resources, etc., where remote resource service scheduling (e.g., remote accessing, information communication) has a large influence on the MGrid quality of service (QoS). The probability of failure is higher in MGrid resource service scheduling and failures affect task execution and the quality of service of the MGrid fatally. Therefore, this paper focuses on failures in the MGrid resource service scheduling process. The potential failures that can occur during MGrid resource service scheduling are investigated. Thirteen failures are first defined in detail and are classified into four categories: (a) virtual-link-related failures, (b) resource-service-related failures, (c) task-related failures, and (d) application-related failures. A failure management system of the MGrid system is presented associated with its architecture. Corresponding detection mechanisms and methods for each defined failure are presented in detail, as well as the corresponding failure recovery methods. The implementation and simulation results indicate that our approaches are sound for promoting a successful scheduling rate and shortening the total execution time of the MGrid resource service.

Structural Estimation and Solution of International Trade Models with Heterogeneous Firms

We present an empirical implementation of a general-equilibrium model of international trade with heterogeneous manufacturing firms. The theory underlying our model is consistent with Melitz (2003). A nonlinear structural estimation procedure identifies a set of core parameters and unobserved firm-level trade frictions that best fit the geographic pattern of trade. Once the parameters are identified, we utilize a decomposition technique for computing general-equilibrium counterfactuals. We illustrate this technique using trade and protection data from the Global Trade Analysis Project (GTAP). We first assess the economic effects of reductions in measured tariffs. Taking the simple-average welfare change across regions the Melitz structure indicates welfare gains from liberalization that are nearly four times larger than in a standard policy simulation model. Furthermore, when we compare the economic impact of tariffs with reductions in estimated fixed trade costs we find that policy measures affecting the fixed costs of firmentry are of greater importance than conventional tariff barriers.

The Research of Execute Process and Service Selecting under Manufacturing Grid Workflow

MG workflow can be defined as the composition of manufacturing activities which execute on heterogeneous and distributed manufacturing resources in a well-defined order to accomplish a specific goal. The execute process of MG workflow includes model building, service finding, service selecting, service binding and service invocation. Service selecting is one of the most critical components in MG workflow. So, this research brings forth AHP-based grid nodes choosing method, which takes time, quality, cost, service, fidelity, reliability, policy (TQCSFRP) as rules, and chooses best resource node as target. The dynamic service binding and invocation between an activity request and an optimal service provider is realized when a workflow is in execution. Higher flexibility and self-adaptability of workflow management are achieved. Furthermore, the application architecture is depicted at the end of the paper to illustrate the utilization of MG workflow.

Study on manufacturing grid & its resource service optimal-selection system

The concept of manufacturing grid (MGrid) is to utilize manufacturing resources distributed in heterogeneous systems and different places to collaboratively manufacture products the market requires. The solution is based on adopting grid technologies, information technologies, advanced manufacturing technologies, management technologies, etc., to realize the complete sharing of all kinds of geographically distributed and heterogeneous manufacturing resources in the form of virtual enterprises. After summarizing the grid technology and its applications, we propose the concept of MGrid. The application of grid technology in manufacturing and the related works about MGrid are investigated. The connotation of MGrid are put forward, including its basic features, the structure and main functions, the main research contents, the architecture, and key technologies. A resource service optimal-selection system of MGrid and its main functions are researched, including resource service description, resource service publication, resource service discovery, resource service quality of service (QoS) evaluation, and resource service optimal-selection evaluation. An application prototype, namely magnetic bearing resources sharing and service platform under manufacturing grid, is developed. It validates the resource service sharing and optimal-selection system in MGrid.

A CORBA- and MAS-based architecture for agile collaborative manufacturing systems

An architecture for building up agile collaborative manufacturing systems (ACMS), which is based on common object request broker architecture (CORBA) and multi-agent system (MAS) paradigm, is proposed in the current paper. First, the diverse manufacturing resources, which may be heterogeneous and physically distributed, are MAS-based agentified and CORBA-based encapsulated as the resource agents. Second, the source agents are registered at the system manager agent (SMA) as member agents and subsequently integrated under the proposed architecture to form an ACMS. Third, the member agents communicate and interact with each other to conduct collaborative manufacturing by means of agent interoperation and human-machine interaction. In order to validate the methodology, an experimental system is developed, where several heterogeneous manufacturing resources are well-integrated via their agents in a plug-and-play manner to establish an ACMS prototype. The experiments demonstrate that the proposed architecture, characterized by distribution and openness, provides a feasible solution for developing ACMS, where integratability, reconfigurability, flexibility and agility are achieved.

Capability-based emerging organization of autonomous agents for flexible production control

Flexible structures in the manufacturing domain are of increasing concern. Nowadays, distributed systems for the coordination, management, and control of highly heterogeneous manufacturing structures are under research and development. However, their flexibility is restricted by two main aspects: On the one hand, in the design step of the system designers are implementing mostly static communication and reasoning skills for distributed software systems. On the other hand, knowledge on solutions provided by machine tools are implemented implicitly, i.e., the software system representing a machine tool can only reason on capabilities for a solution with respect to the capabilities implemented by the designer. In this paper we will propose an innovative approach to dynamic capability management enabling software agents to reason on their capabilities and dynamically create capabilities as solutions.

An expanded SEMATECH CIM framework for heterogeneous applications integration

A significant effort in recent computer-integrated manufacturing (CIM) development was carried out by SEMATECH who had laid out and created an open framework for the integration of manufacturing execution system applications running in semiconductor industries at the factory operation level. This paper presents the feasibility to incorporate basic manufacturing applications at the factory engineering level, which include product design, process planning, and material requirement planning, into the SEMATECH CIM framework to form a generic framework across both factory operation level and factory engineering level. The CIM framework established in this paper was aimed to provide a reusable integrated system framework that clearly specifies the functional interface boundaries and standard information model of the required components, in general, manufacturing systems at both factory operation and factory engineering levels. Standard unified modeling language (UML) diagrams and Petri nets have been utilized to model and analyze the specifications and dynamic behaviors of this generic CIM framework. The goal is to build a framework by creating a common, modular, flexible, and integrated object model that unifies an advanced object-oriented architecture concept and heterogeneous manufacturing application development in an open and multisupplier CIM system environment.

A Generic MMS–Based Holon Structure

Abstract This paper is about decentralised intelligent manufacturing systems, with the specific aim of proposing a generic Manufacturing Message Specification (MMS) based holon which can be used to control different manufacturing devices with simple reconfigurations. MMS is avendor–independent communication protocol for manufacturing devices and is used as a tool to control heterogeneous manufacturing devices. The generic MMS–based holon structure was implemented in the Microsoft Windows environment and incorporates stand–alone devices such as a robot or a CNC Lathe into a networked environment. The outcome of the research shows that the MMS protocol is suitable for generating modular mini–structures to implement holonic, biologically oriented and fractal manufacturing systems.

An integrated knowledge representation scheme and query processing mechanism for fault diagnosis in heterogeneous manufacturing environments

An integrated fault diagnosis system was developed for manufacturing complex products, e.g., automobile, that undergo a variety of production processes. The proposed global knowledge representation scheme is designed to consistently express such heterogeneous diagnostic knowledge in terms of the causal relations among relevant attributes across different processes. This scheme is unifying in that it reflects the fact that an effect for one causal relation may in turn be a cause for another along a chain of subsequent processes. In order to unify independent pieces of causal relation, specific attributes of machine-processed products in addition to the usual diagnostic signals such as noise and voltage of the machines. The accompanying probabilistic diagnosis mechanism can then produce an enhanced diagnostic accuracy over other existing schemes as it can simultaneously consider multiple causes of a fault along with their interdependency. The proposed diagnosis mechanism was implemented in a distributed computer environment to identify the functions and procedures required for its actual application.

Integrating multimedia communications into an MMS environment

This paper presents an approach of network resource management in a heterogeneous manufacturing LANs environment in order to integrate multimedia services. The primary objective is to define a uniform communication interface with which the multimedia functionality can be integrated into the distributed manufacturing applications. The proposed model extends the Virtual Manufacturing Device (VMD) concept defined in the international standard Manufacturing Message Specification (MMS) in order to virtualise the communication systems. A virtual server, named Virtual Communication Support (VCS), is defined to provide the transparent services on the QoS (Quality of Service) parameters negotiation, the communication channel establishment/termination and QoS monitoring in a standardised constrained industrial communications framework. Multimedia application and traditional manufacturing applications have to co-exist in a standardised MMS environment. Furthermore the VCS model provides the support for the possible real-time extension of MMS. A platform of implementation, named PLACOMAP, is presented to illustrate a multimedia enhanced manufacturing application in a heterogeneous communication context where different types of networks, ATM, ETHERNET and MAP are involved.

Communicating MMS Events in a Distributed Manufacturing System Using CORBA

Nowadays, distributed computing systems are widely used due to the great advances that have been achieved in computer networks in the past few years, and partly due to their low cost. Developing software for these systems turns out to be complicated, mainly due to the heterogeneity of the distributed system components and the underground communication layers. MMS is a suitable language to carry out the communication between devices in a heterogeneous manufacturing system because it provides uniformity in the access to them. This work proposes the use of the ORB specified in CORBA from the OMG to communicate MMS events.

An integrated fault diagnostic mechanism based on statistical characteristics of products for heterogeneous manufacturing environments

A fault diagnosis mechanism for heterogeneous manufacturing environments is developed. Using the correlation coefficient among quality characteristic values (QCVs) of products enables the functional correlation between processes to be uniformly treated according to causal relations among processes, despite their functional heterogeneity. Complex causal relations between QCVs are graphically represented by the influence graph, which is developed to model the diagnostic knowledge of our method. This mechanism realizes more accurate diagnostic capabilities than black-box methods, and still, does not require exhaustive modelling of the entire process, unlike model-based reasoning methods. The viability of this diagnostic approach was verified via simulation.

Development of a unified data meta-model for CAD-CAPP-MRP-NC verification integration

This paper presents an architecture and a schema for the integration of heterogeneous manufacturing databases. Termed the Unified Data Meta Model (UDMM), this structure is based on common relational data modeling methods and was developed to support the integration of CAD, CAPP, NC tool path verification and MRP systems. The model was developed based upon an analysis of the existing manufacturing operations of three major corporations and the data structures of popular CAD, CAPP, MRP and NC verification software tools. Key features of the UDMM include the fact that data instantiated for communication is not persistent and it represents the union of the intersection of the information represented by the local software tools. The specification of the UDMM, and the nature of the integration architecture is such that it allows for the extension of both attributes in the model and new entities as new manufacturing functional domains are added.

Design principles for open and reusable shop-floor control software

Integrating a heterogeneous manufacturing environment means using information technology to provide appropriate access to accurate and timely information. While individual systems provide valuable solutions to particular manufacturing or transport problems, quick and easy information-sharing throughout the shop-floor has become almost impossible. Yet, information-sharing is increasingly critical for the success of the company and its manufacturing goals. Whether data comes from a device or an application in the manufacturing environment, the critical success factor in shop-floor integration is the ability to turn data into useful information, to distribute it, and to share it regardless of application, device, hardware, operating system, and network used. Manufacturing environments are changing constantly and the technology surrounding and supporting them is often changing faster. Solving manufacturing problems by acquiring a variety of incompatible hardware and software from multiple vendors has created a complex application and device integration problem. This paper describes an approach that makes the task of application integration easier. The concept focuses on achieving application independence and was verified in an assembly cell at a truck component factory.

Fault-tolerant heterarchical control of heterogeneous manufacturing system entities

Fault-tolerant heterarchical control of heterogeneous manufacturing system entities

A Research Note: Centralization of Decision-making in Japanese Factories

Using the Aston Centralization of Authority scale, this paper shows that Japanese organizations vary in their level of overall centralization of authority in decision- making, and in the level at which decisions in particular areas are made. In a sample of 48 heterogeneous Japanese manufacturing firms it is found that both spatial dispersion into multiple sites and higher levels of automation of technology increase centralization of authority, while large size and the increasing number of levels to which size gives rise, and greater task variability all have the opposite effect, i.e., they lower, somewhat, the levels at which decisions can be made. The implications of these findings for claims of 'bottom-up', participative deci sion-making in Japan's ringi system are discussed in the conclusion.