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Peter Haase Bjrn Schnizler Jeen Broekstra Marc Ehrig Frank van Harmelen Maarten Menken Peter Mika Michal Plechawski Pawel Pyszlak Ronny Siebes Steffen Staab Christoph Tempich 《Journal of Web Semantics》2004,2(1):99-103
This paper describes Bibster, a Peer-to-Peer system for exchanging bibliographic metadata among researchers. We show how Bibster exploits ontologies in data-representation, query formulation, query routing, and query result presentation. The Bibster system is freely available and is used by researchers across multiple organizations. 相似文献
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Keyword‐based search engines such as Google? index Web pages for human consumption. Sophisticated as such engines have become, surveys indicate almost 25% of Web searchers are unable to find useful results in the first set of URLs returned (Technology Review, March 2004). The lack of machine‐interpretable information on the Web limits software agents from matching human searches to desirable results. Tim Berners‐Lee, inventor of the Web, has architected the Semantic Web in which machine‐interpretable information provides an automated means to traversing the Web. A necessary cornerstone application is the search engine capable of bringing the Semantic Web together into a searchable landscape. We implemented a Semantic Web Search Engine (SWSE) that performs semantic search, providing predictable and accurate results to queries. To compare keyword search to semantic search, we constructed the Google CruciVerbalist (GCV), which solves crossword puzzles by reformulating clues into Google queries processed via the Google API. Candidate answers are extracted from query results. Integrating GCV with SWSE, we quantitatively show how semantic search improves upon keyword search. Mimicking the human brain's ability to create and traverse relationships between facts, our techniques enable Web applications to ‘think’ using semantic reasoning, opening the door to intelligent search applications that utilize the Semantic Web. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Many organizations often need to share semantic knowledge base content with selected members of other organizations. However, sharing semantic knowledge across different organizations is a critical problem. This is because the differences in the vocabulary utilized by the organizations have to be resolved before knowledge can be shared. Also, if semantic repositories are syntactically and schematically heterogeneous, information interoperation becomes a vital challenge. When a system needs to allow unknown entities to access its resources, mechanisms should be in place in order to provide a secure and trusted information-sharing environment and enable users to interact and share information easily and perfectly. To address these challenges, the Mediator Authorization-Security model is proposed to provide secure interoperation among heterogeneous semantic repositories. This paper addresses the issue of interoperability and how to incorporate trust into semantic interoperability. The evaluation showed that, despite the complexity of the mediator system, it still provides acceptable performance. 相似文献
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Product configuration is a crucial means to implement the mass customization paradigm by assembling a set of customizable components to satisfy both customers’ needs and technical constraints. With the aim of enabling efficient and effective development of product configuration systems by reusing configuration knowledge, an ontology-based approach to modeling product configuration knowledge is presented in this paper. The ontology-based product configuration models are hierarchically organized. At the lower level, a configuration meta-model is defined. Based on this meta-model, domain-specific configuration knowledge can be derived by reusing or inheriting the classes or relations in the meta-model. Configuration models are formalized using OWL (Ontology Web Language), an ontology representation language developed by W3C. As a result, configuration models have well-defined semantics due to the logic semantics of OWL, making it possible to automatically detect inconsistencies of configuration knowledge bases. Furthermore, configuration constraints are represented in SWRL, a rule language based on OWL. Finally, actual configuration processes are carried out using JESS, a rule engine for the Java platform, by mapping OWL-based configuration facts and SWRL-based configuration constraints into JESS facts and JESS rules, respectively. The proposed methodology is illustrated with an example for configuring the ranger drilling machine. 相似文献
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STEP标准和STEP标准的形式化信息描述语言EXPRESS在数据格式上统一了产品信息的建模标准,实现了语法层面上的数据交换和互操作能力.而当今计算环境要求基于语义Web的语言来描述产品信息,以实现产品信息在知识级的交换和共享,STEP没有提供这种特性.介绍了由W3C主持制定的Web本体语言OWL,并用实例给出了OWL在产品信息表达中的应用. 相似文献
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OWL本体描述语言包含相对丰富的概念定义符,但提供的关系定义符描述能力则较差。将OWL与规则相结合是克服这种表达能力限制的一种常用方法。Motik提出了一种可判定的方法,将SHIQ(D)描述逻辑与规则结合,所结合的规则限定在一种叫做DL-safe规则的范围内。本文提出了一种抽取DL-safe规则的方法,方法利用SHIQ(D)逻辑中的UNION定义符满足一些规则在前件中包含析取逻辑运算符的需求,从而扩展了规则的描述能力。 相似文献
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语义网服务中的本体综述 总被引:2,自引:2,他引:2
作为实现下一代Web的集成方案,语义网服务将语义Web技术和Web服务技术相结合,以支持Web服务的自动发现、选择、合成和执行.本体是语义网服务的理论基础.介绍了Web资源描述本体OWL和Web服务描述本体的概况,并对3种主流的Web服务语义描述框架进行对比分析,为语义网服务中本体的创建提供基础知识.研究了语义网服务中存在的各层次的本体异构问题,明确了语义网服务中本体集成的主要研究方向. 相似文献
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This paper presents WebOWL, an experiment in using the latest technologies to develop a Semantic Web search engine. WebOWL consists of a community of intelligent agents, acting as crawlers, that are able to discover and learn the locations of Semantic Web neighborhoods on the Web, a semantic database to store data from different ontologies, a query mechanism that supports semantic queries in OWL, and a ranking algorithm that determines the order of the returned results based on the semantic relationships of classes and individuals. The system has been implemented using Jade, Jena and the db4o object database engine and has successfully stored over one million OWL classes, individuals and properties. 相似文献
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一种基于本体的团队知识共享模型 总被引:4,自引:0,他引:4
针对在Internet环境下进行项目开发的特点,提出一种团队知识共享模型,通过使用OWL表示的领域本体和应用本体来组织分散在Internet环境中的知识,并在此基础上定义了基本知识操作,使得Internet下的团队成员能够进行项目知识的查询、发布及订阅,方便了团队成员之间的知识共享。 相似文献
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吕艳辉 《小型微型计算机系统》2011,32(5)
经典OWL本体不能直接表示和处理语义Web应用中广泛存在的模糊知识,鉴于模糊关系数据库在模糊数据表示与处理方面的优势,提出利用模糊关系数据库来构建模糊OWL本体.通过对RDF数据类型进行模糊扩展,并从模糊数据类型角度扩展OWL,解决了模糊OWL本体的表示问题;在此基础上,研究了以模糊关系数据库为数据源的模糊OWL本体的构建方法,该方法为语义Web中模糊本体的构建提供了一个有效的解决方案. 相似文献
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In the context of technological expansion and development, companies feel the need to renew and optimize their information systems as they search for the best way to manage knowledge. Business ontologies within the semantic web are an excellent tool for managing knowledge within this space. The proposal in this article consists of a methodology for integrating information in companies. The application of this methodology results in the creation of a specific business ontology capable of semantic interoperability. The resulting ontology, developed from the information system of specific companies, represents the fundamental business concepts, thus making it a highly appropriate information integration tool. Its level of semantic expressivity improves on that of its own sources, and its solidity and consistency are guaranteed by means of checking by current reasoning tools. An ontology created in this way could drive the renewal processes of companies’ information systems. A comparison is also made with a number of well-known business ontologies, and similarities and differences are drawn, highlighting the difficulty in aligning general ontologies to specific ones, such as the one we present. 相似文献
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Soheil Hassas Yeganeh Author Vitae Hassan Abolhassani Author Vitae 《Computers & Electrical Engineering》2010,36(5):805-817
A huge amount of web services are deployed on the Web, nowadays. These services can be used to fulfill online requests. Requests are getting more and more complicated over time. So, there exists a lot of frequent request that cannot be fulfilled using just one web service. For using web services, composing individual services to create the added-value composite web service to fulfill the user request is necessary in most cases. Web services can be composed manually but it is a too tedious and time consuming task. The ability of automatic web service composition to create a new composite web service is one of the key enabling features for the future for the semantic web. There are some successful methods for automatic web service composition, but the lack of standard, open, and lightweight test environment makes the comparison and evaluation of these composition methods impossible. In this paper we propose an architecture for a light weight and scalable testbed to execute, test and evaluate automatic web service composition algorithms. The architecture provides mandatory components for implementing and evaluation of automatic web service composition algorithms. Also, this architecture provides some extension mechanisms to extend its default functionalities. We have also given reference implementations for web service matchmaking and composition. Also, some scenarios for testing and evaluating the testbed are given. We have found that the performance of the composition method will dramatically decrease as the number of web services increases. 相似文献
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Ontologies provide formal, machine-readable, and human-interpretable representations of domain knowledge. Therefore, ontologies have come into question with the development of Semantic Web technologies. People who want to use ontologies need an understanding of the ontology, but this understanding is very difficult to attain if the ontology user lacks the background knowledge necessary to comprehend the ontology or if the ontology is very large. Thus, software tools that facilitate the understanding of ontologies are needed. Ontology visualization is an important research area because visualization can help in the development, exploration, verification, and comprehension of ontologies. This paper introduces the design of a new ontology visualization tool, which differs from traditional visualization tools by providing important metrics and analytics about ontology concepts and warning the ontology developer about potential ontology design errors. The tool, called Onyx, also has advantages in terms of speed and readability. Thus, Onyx offers a suitable environment for the representation of large ontologies, especially those used in biomedical and health information systems and those that contain many terms. It is clear that these additional functionalities will increase the value of traditional ontology visualization tools during ontology exploration and evaluation. 相似文献
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This article describes AQUA, an experimental question answering system. AQUA combines Natural Language processing (NLP), Ontologies, Logic, and Information Retrieval technologies in a uniform framework. AQUA makes intensive use of an ontology in several parts of the question answering system. The ontology is used in the refinement of the initial query, the reasoning process and in the novel similarity algorithm. The similarity algorithm is a key feature of AQUA. It is used to find similarities between relations/concepts in the translated query and relations/concepts in the ontological structures. The similarities detected then allow the interchange of concepts or relations in a logic formula corresponding to the user query. 相似文献
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