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Information integration is vital for keeping manufacturing operations competitive. A case study approach has been adopted to better understand the role of informatio in integrated manufacturing. Information is now considered a corporate asset. The creation, processing, movement and security of information is therefore as important as the products/services of an enterprise. The case studies have helped in identifying the requirements and issues involved in developing an information system and supporting software framework for a manufacturing enterprise. This paper deseribes a case study dealing with the integrated manufacture of optical fiber products. A phased development and implementation approach was adopted where a small, manageable slice of the system is considered for the case study followed by functional modeling (IDEFO) and data flow modeling (data flow diagrams). This identifies the pieces of information of interest. The information relationships are modeled using extended entity relationship (EER) diagrams which are then mapped to a relational model. The relational tables thus obtained were implemented on a commercial Database Management System (DBMS). The functional constraints and application interfaces were then built using Structured Query Languages (SQL) and commercial application interface tools. Subsequent sections describe the functional models, data flow diagrams (DFDs), EER diagrams, relational database design and user/application interfaces developed for the system. Implementation experiences and observations are discussed along with the applications of the implemented system. The case study has helped in developing a preliminary data model (i.e., a model about data by which a reasonable interpretation of the data can be obtained) for material handling (MH) functions.  相似文献   

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One of the main problems when implementing the computer-integrated manufacturing (CIM) concept concerns information integration. In order to support information integration, an information system provided with suitable data models is required. In this paper an information system is presented, which fulfils the requirements for an appropriate information management in CIM. For this purpose, an EXPRESS-oriented information system has been built on top of a commercial relational DBMS. The conceptual model of the information is built in EXPRESS and then parsed and translated to the corresponding relational constructs. A data access interface has been implemented which allows EXPRESS-oriented data manipulation. The information system was developed inside ESPRIT project No. 2202 CIM-PLATO “CIM System Planning Toolbox” to integrate the information used by the tools developed for flexible manufacturing system planning.  相似文献   

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An object-oriented paradigm is established as the leading approach for developing non-traditional applications, such as GIS or multimedia systems. On the other hand, relational databases have dominated the area of data processing in the past decade. These two trends motivate the research on integrating OO applications with relational databases. This paper presents our approach to the symbiosis of the OO and relational data models, which is built into GinisNT, a scalable OO GIS framework based on an OO-to-relational mapping algorithm. The mapping algorithm transforms classes and objects into relations and tuples, and vice versa, instantiates objects from relational databases. The methodology presented here is extremely efficient, as has been proved by a number of applications developed in GinisNT, and is at the same time cost efficient, as it builds upon existing platforms.  相似文献   

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OntoRBAC:基于本体的RBAC策略描述与集成   总被引:2,自引:1,他引:2  
随着分布式安全系统研究的不断深入和发展,基于策略的体系结构已经逐步成为了访问控制系统中的一种主流方法。然而这些策略的定义均建立在特定的语言基础上。如何在异构的系统间进行集成尚缺乏有效的机制。本文提出了一种基于本体的访问控制策略定义机制——OntoRBAC——它完全支持了RBAC96模型,利用本体这个工具,能够为访问控制策略的制定提供更精确、更强大的描述能力,并且可以实现从语义层次上对不同策略的集成。而借助于SWRL(Semantic Web Rule Language),我们定义了多条适用于OntoRBAC的规则来进行对访问控制决策的推理。最后,介绍了这个系统的实现框架。  相似文献   

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Providing integrated access to multiple, distributed, heterogeneous databases and other information sources has become one of the leading issues in database research and the industry. One of the most effective approaches is to extract and integrate information of interest from each source in advance and store them in a centralized repository (known as a data warehouse). When a query is posed, it is evaluated directly at the warehouse without accessing the original information sources. One of the techniques that this approach uses to improve the efficiency of query processing is materialized view(s). Essentially, materialized views are used for data warehouses, and various methods for relational databases have been developed. In this paper, we first discuss an object deputy approach to realize materialized object views for data warehouses which can also incorporate object-oriented databases. A framework has been developed using Smalltalk to prepare data for data warehousing, in which an object deputy model and database connecting tools have been implemented. The object deputy model can provide an easy-to-use way to resolve inconsistency and conflicts while preparing data for data warehousing, as evidenced by our empirical study.  相似文献   

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Distributed manufacturing execution systems: A workflow perspective   总被引:7,自引:0,他引:7  
Research of manufacturing execution systems (MESs) has been conducted to integrate ERP and physical operational systems, so a fully automated and integrated manufacturing management environment can be developed. However, as subcontracting becomes common in industries, a single MES is not enough and it is necessary to develop distributed MESs to integrate the distributed operations. This research proposes a distributed workflow model to develop such a system. In the workflow model, there are three cooperation types for defining the relationships between an action and resources. Six relational patterns are defined for the relationships between actions. This research also reviews current information technologies, including data acquisition and control (DAC) components, control software's, ASP .NET, and CLIPS, for supporting the development of distributed workflow models. Additionally, this research proposes using a collaborative workflow-based protocol (CWP) to form a distributed workflow. CWP is based on the integration of Internet technology and CLIPS. It is found that the proposed structure may ease the decision process of forming a distributed workflow. In summary, this article reports a cutting edge approach for the development of distributed manufacturing execution systems. The results show solutions for integrating high-level planning systems, such as ERP, and low-level operational systems through information technologies.  相似文献   

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Due to enormous pressure from national and international marketplaces, computer integrated manufacturing ( cim) has become a tremendously important area for both research and development. However, the current state of the art is still characterized by islands of automation. In order to connect these islands, appropriate frameworks have to be developed to integrate heterogeneous computer aided design ( cad) tools. We present in this paper a federated approach to tool integration in distributed and heterogeneous environments making tools evolve in an autonomous way. We have experimented this approach by integrating propel and spex cad tools in the dmms ( design management and manufacturing system) environment backed by a common pcte providing an open repository for software development. We use in our experiment an implementation of pcte 1.5 named Emeraude V12.5, product of gie emeraude repository.  相似文献   

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The increasing competition among industries has leveraged the emergence of various tools and methods for maintenance decision-making support. This paper identifies in literature the application areas of industrial maintenance decision-making, the relationships between these areas and the ways in which authors integrate tools and methods. This information makes it possible to identify trends and deficiencies in this context, helping to centralize the efforts required for future work. This work follows a series of structured steps for a systematic literature review of papers related to the main topic available in online databases. The selected papers are subject to a content assessment and grouped according to the application areas. The direct comparison between these areas and the construction of a relational matrix provide a quantitative interpretation of the results and well-structured information. Additionally, this paper proposes a framework based on information from the literature, which summarizes the origin and flow of information used in the development of models, showing the relationship among application areas of decision making. The research undertaken identifies trends focused on joint production systems optimization and increasing the deployment of methods for autonomous equipment predictions.  相似文献   

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The trend in healthcare information technology is increasingly digital and multimedia oriented. The next generation of health care information systems will consist of a vast network of heterogeneous, autonomous, and distributed imaging scanners, databases, information systems, knowledge intensive applications, and large quantities of multimedia medical data. A key challenge facing system researchers and builders is to provide a new organizational framework that can integrate this varied collection of resources into what appears to be a uniform and logical conglomeration of data and knowledge store in order to increase the availability of global or previously nonaccessible information and to address demanding new information processing requirements for diverse image-assisted medical applications. The purpose of this paper is to present the authors' research toward the development of a hospital integrated framework of multimodality image base management (MIBM) for digital radiology of the future. This evolutionary framework consists of three hierarchical components: a hospital-integrated picture archiving and communication system (HI-PACS), a medical image database system (MIDS), and a set of image-based medical applications that relies on the support of MIDS and PACS. In this paper, the authors describe the system architecture, guiding principles, and design specifications of HI-PACS and MIDS and illustrate their functions and capabilities with three implemented applications, namely, patient folder workflow, distributed object management, and multimodality imaging studies. In addition, the authors conclude their findings with a summary of challenges and research directions  相似文献   

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In a large-scale design process, designers cooperate in a complex situation where a variety of software tools run on different hardware platforms. This paper presents a data enhancement approach to integrate heterogeneous Computer-Aided Design (CAD) databases through the Internet. The data enhancement means topological changes in a geometric model and additional information in design semantics. The geometric data is enhanced using a non-manifold modeler to produce data sets valuable in downstream applications such as a Finite Element Method (FEM) solver or a detail design system. As a practical example, a shipbuilding product model database has been implemented based on the Standard for the Exchange of Product (STEP) model data methodology and shipbuilding features. The system has been implemented on a network environment that consists of a Web browser, Common Object Request Broker Architecture (CORBA) objects, a relational database management system, a data enhancement module, and various computer-aided applications.  相似文献   

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Recommended practices supplement data exchange standards by providing common implementation guidance associated with specific requirements. ISO 10303 (STEP) product data exchange files that conform to recommended practices ensure interoperability between computer-aided design (CAD) systems and with downstream applications such as manufacturing and inspection. Correct implementation of product and manufacturing information (PMI)–annotations associated with a CAD model’s edges and faces such as geometric tolerances, dimensional tolerances, and datum features–in CAD authoring systems and translators is essential for interoperability. This paper discusses an approach implemented in a software tool for checking the conformance of STEP files to the recommended practice for PMI representation.  相似文献   

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SEEKER:基于关键词的关系数据库信息检索   总被引:23,自引:3,他引:20  
文继军  王珊 《软件学报》2005,16(7):1270-1281
传统上,SQL是存取关系数据库中数据的主要界面.但是,对于没有经验的用户来说,学习复杂的SQL语法是一件困难的事情.实现基于关键词的关系数据库信息检索,将使用户不需要任何SQL语言和底层数据库模式的知识,用搜索引擎的方式来获取数据库中的相关数据.描述了一个基于关键词的关系数据库信息检索系统SEEKER的设计和实现.现有的关系数据库关键词查询系统只能检索关系数据库中的文本属性,而SEEKER还可以检索数据库元数据以及数字属性.并且,SEEKER采用了更合理的排序公式,支持Top-k查询.实验结果显示,SEEKER具有良好的查询性能.  相似文献   

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Focuses on the development of a methodology within a software environment for automating the rule-based implementation of specifications of integrated manufacturing information systems. The specifications are initially formulated in a natural language and subsequently represented in terms of a graphical representation by the system designer. A new graphical representation tool is based on updated Petri nets (UPN) that we have developed as a specialized version of colored Petri nets. The rule-based implementation approach utilizes the similarity of features between UPN and the general rule specification language used for the implementation. The automation of the translation of UPN to the rule specification language is expected to considerably reduce the life-cycle for design and implementation of the system. The application presented deals with the control and management of information flow between the computer-aided design, process planning, manufacturing resource planning and shop floor control databases. This provides an integrated information framework for computer integrated manufacturing systems  相似文献   

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《Knowledge》2000,13(1):11-19
In the last few years, the WWW has frequently been used in a variety of applications, to provide up-to-date and platform-independent access to relevant information. In medicine, building and sharing knowledge about new theories, technologies and discoveries is of major concern. In this respect, there is a real need for physicians to be provided with efficient tools that offer targeted access to information about literature, expert opinions, medical statistics and epidemiology, in order to help them in their decision process. In this paper we describe the design and implementation of a generic Web-based environment that provides physicians with an integrated access to medical information as well as decision making support facilities. The emphasis is given on the design issues and the benefits of combining several approaches: using structured documents and databases to manage information and, argumentation tools to support the communication.  相似文献   

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Plastic parts, especially those designed for consumer electronics products, are becoming more compact and freeform in shape. This requires the construction of compact and delicate geometric features in the injection moulds that produce these parts. It is now common practice to employ electric discharge machining (EDM) whenever the conventional machining process fails to machine such delicate features. Although CAD/CAM systems are widely used in mould design and manufacturing, and specific commercial CAD/CAM systems that are customized for injection mould applications are also available, there are still no intelligent CAD tools that address the specific requirements of EDM electrode design. The aim of this research is to develop an intelligent CAD tool that supports EDM electrode design. This CAD tool uses a new technique that recursively splits the EDM region into sub-regions until machinable electrodes can be constructed. The CAD tool has been implemented and integrated into a commercial CAD/CAM system, and 40 different real designs has been used to test its capability in handling a wide variety of geometric shapes. Performance data show that the efficiency of the design process can be improved by at least 50%, with a potential to achieve 85% through improved implementation and further research.  相似文献   

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1 Introduction The scalability of virtual environments (VEs) that allow users to change and modify their contents and context depending on application requirements has been a de facto feature of virtual reality technology. Engineering uses such as virtual testing and exper- imenting applications demand VEs to be highly or fully reconfigurable. In reality, however, satisfactory reconfiguration of a virtual environment is yet to be achieved, due to the high accuracy of spatial data in- put and…  相似文献   

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The object-oriented approach is being used in several areas of computing, including programming, databases, computer-aided design, and office information systems. The paper is a tutorial introduction to object-oriented databases, which is a new application in this field, although object-oriented programming has been under development since the late 1960s. The paper describes the background to object-oriented databases and outlines the rationale for this approach. It concludes with a possible application, in this case a cartographic database, explaining why the object-oriented approach is more appropriate to this application than traditional database approaches, such as the relational approach.  相似文献   

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