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OWL本体到关系数据库模式的映射 总被引:6,自引:2,他引:4
通过对现有本体存储模式的分析,以及对OWl本体和关系数据库模式之间的概念对应关系的分析,定义了从OWL本体到关系数据库模式的转换规则,给出了OWL本体存储模式的设计原则,并基于该原则提出了一种新的本体存储模式.针对本体描述语言OWL的构词特点,该模式提出将本体中的语义信息存放在不同的表中,以达到方便理解、结构稳定和提高效率的目的,适应于多数中小型本体的存储. 相似文献
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We develop a logic for entity-relationship databases, ERL, that is a generalization of database logic. ERL provides advantages to the ER model much as FOL (first-order logic) does to the relational model: a uniform language for expressing database schema, integrity constraints, and database manipulation; clearly defined semantics; the capability to express database transformations; and deductive capabilities. We propose three query languages for ER databases called ERRC, ERSQL, and ERQBE, which are generalizations of the relational calculus, SQL, and QBE, respectively. We use example queries and updates to demonstrate the capabilities of these languages. We apply database transformations to introduce the notion of views and to show that both ERRC and ERSQL are relationally complete.Research sponsored in part by the National Science Foundation under grant IRI-8921951 and by Towson State University. 相似文献
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Most of nowadays Web content is stored in relational databases. It is important
to develop ways for representation of this information in the Semantic Web to allow software
agents to process it intelligently. The paper presents an approach to translation of data,
schema and the most important constraints from relational databases into the Semantic
Web without any extensions to the Semantic Web languages. 相似文献
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Markowitz V.M. Makowsky J.A. 《IEEE transactions on pattern analysis and machine intelligence》1990,16(8):777-790
Relational schemas consisting of relation-schemes, key dependencies and key-based inclusion dependencies (referential integrity constraints) are considered. Schemas of this form are said to be entity-relationship (EER)-convertible if they can be associated with an EER schema. A procedure that determines whether a relational schema is EER-convertible is developed. A normal form is proposed for relational schemas representing EER object structures. For EER-convertible relational schemas, the corresponding normalization procedure is presented. The procedures can be used for analyzing the semantics of existing relational databases and for converting relational database schemas into object-oriented database schemas 相似文献
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A significant interest developed regarding the problem of describing databases with expressive knowledge representation techniques in recent years, so that database reasoning may be handled intelligently. Therefore, it is possible and meaningful to investigate how to reason on fuzzy relational databases (FRDBs) with fuzzy ontologies. In this paper, we first propose a formal approach and an automated tool for constructing fuzzy ontologies from FRDBs, and then we study how to reason on FRDBs with constructed fuzzy ontologies. First, we give their respective formal definitions of FRDBs and fuzzy Web Ontology Language (OWL) ontologies. On the basis of this, we propose a formal approach that can directly transform an FRDB (including its schema and data information) into a fuzzy OWL ontology (consisting of the fuzzy ontology structure and instance). Furthermore, following the proposed approach, we implement a prototype construction tool called FRDB2FOnto. Finally, based on the constructed fuzzy OWL ontologies, we investigate how to reason on FRDBs (e.g., consistency, satisfiability, subsumption, and redundancy) through the reasoning mechanism of fuzzy OWL ontologies, so that the reasoning of FRDBs may be done automatically by means of the existing fuzzy ontology reasoner.© 2012 Wiley Periodicals, Inc. 相似文献
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随着本体种类和资源的增加,本体的结构越来越复杂,为了合理地存储各种结构类型的本体、支持高效的本体查询,本文提出了一种基于关系数据库的OWL本体存储方法。该方法通过细致考虑OWL的基本元素,采用与传统的本体分解存储模式不同的构词分类方法,将OWL本体中的类、属性、实例、属性特征和属性约束分别存储在一张二维表中,从而解决了资源与属性值之间的复杂关系问题,并保证了OWL本体存储到关系数据库后语义信息的完整性。最后,利用关系数据库管理系统高效的检索和匹配速度以及SQL语言的高度非过程化,将检索和匹配OWL本体转换成检索关系数据库,弥补了OWL本体数据查询效率低的不足之处。 相似文献
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In this paper, we introduce our solution for mapping local ontologies to relational and object‐oriented representations. This solution is part of the GeoNis framework for the interoperability of geo‐information systems applications in a local community environment. The GeoNis framework is based on a hybrid ontology approach for data integration. Therefore, a very important subject in our research on semantic data integration is the creation of mapping between a spatial information source and its local ontology. We developed the OWL2RDB mapping language to create an intermediate layer between a relational database and the OWL ontology. This intermediate layer contains rules (expressed in the OWL2RDB language) for mapping between the structural elements of a relational database and the concepts of OWL ontologies. We also present a system that uses the OWL2RDB intermediate layer to create classes that can handle ontology instances stored in relational databases. We have developed a prototype for a tool that uses this proposed approach for the automatic generation of translator/wrapper components in the GeoNis interoperability environment. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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在研究OWL本体的存储模式和现有的基于关系数据库本体存储模式的基础上,本文提出了一种新的基于关系数据库存储OWL本体的方法。该方法根据OWL的构词特征,设计关系表来保存本体中资源之间的关系,描述了特征和约束、刻画了本体的层次和等价等关系,很好地存储了本体的语义信息。它适用于存储大规模的本体,同时大大提高了检索、查询、映射的效率。 相似文献
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《Information and Software Technology》1999,41(4):183-196
Wrappers export the schema and data of existing heterogeneous databases and support queries on them. In the context of cooperative information systems, we present a flexible approach to specify the derivation of object-oriented (OO) export databases from local relational databases. Our export database derivation consists of a set of extent derivation structures (EDS) which defines the extent and deep extent of export classes. Having well-defined semantics, the EDS can be readily used in transforming wrapper queries to local queries. Based on the EDS, we developed a wrapper query evaluation strategy which handles OO queries on the export databases. The strategy is unique in that it considers the limited query processing capabilities of local database systems as well as the language constraints on the local query languages. 相似文献
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Leopoldo Bertossi Camilla Schwind 《Annals of Mathematics and Artificial Intelligence》2004,40(1-2):5-35
In this article, we characterize in terms of analytic tableaux the repairs of inconsistent relational databases, that is databases that do not satisfy a given set of integrity constraints. For this purpose we provide closing and opening criteria for branches in tableaux that are built for database instances and their integrity constraints. We use the tableaux based characterization as a basis for consistent query answering, that is for retrieving from the database answers to queries that are consistent with respect to the integrity constraints. 相似文献
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XML has become the standard for publishing and exchanging data on the Web. However, most business data is managed and will
remain to be managed by relational database management systems. As such, there is an increasing need to efficiently and accurately
publish relational data as XML documents for Internet-based applications. One way to publish relational data is to provide
virtual XML documents for relational data via an XML schema which is transformed from the underlying relational database schema
such that users can access the relational database through the XML schema. In this paper, we discuss issues in transforming
a relational database schema into the corresponding XML schema. We aim to preserve all integrity constraints defined in a
relational database schema, to achieve high level of nesting and to avoid introducing data redundancy in the transformed XML
schema. In the paper, we first propose a basic transformation algorithm which introduces no data redundancy, then we improve
the algorithm by exploring further nesting of the transformed XML schema. 相似文献
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Raphael Barbau Sylvere Krima Sudarsan Rachuri Anantha Narayanan Xenia Fiorentini Sebti Foufou Ram D. Sriram 《Computer aided design》2012,44(6):575-590
The representation and management of product lifecycle information is critical to any manufacturing organization. Different modeling languages are used at different lifecycle stages, for example STEP’s EXPRESS may be used at a detailed design stage, while UML may be used for initial design stages. It is necessary to consolidate product information created using these different languages to build a coherent knowledge base. In this paper, we present an approach to enable the translation of STEP schema and its instances to Ontology Web Language (OWL). This gives a model–which we call OntoSTEP–that can easily be integrated with any OWL ontologies to create a semantically rich model. As an example, we combine geometry information represented in STEP with non-geometry information, such as function and behavior, represented using the NIST’s Core Product Model (CPM). A plug-in for Protégé is developed to automate the different steps of the translation. As additional benefits, reasoning, inference procedures, and queries can be performed on enriched legacy CAD models. We describe the rules for the translation from EXPRESS to OWL, and illustrate the benefits of OWL translation with an example. We will also describe how these mapping rules can be implemented through meta-model based transformations, which can be used to map other languages to OWL. 相似文献
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RDFS(FA): Connecting RDF(S) and OWL DL 总被引:1,自引:0,他引:1
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对象角色建模(ORM)方法已应用于本体工程,因此需要将ORM模型转换为OWL DL公理,以便将ORM本体发布到语义Web上,同时还可使用支持DL的推理机来检查ORM本体的语义一致性和冗余问题。通过模型语义分析、模型等价转换、引入新的运算符和特性等方法,提出将ORM模型形式化表达为OWL DL公理的规则。除了外部唯一约束等四种约束外,其他形态的ORM模型都可以形式化表达为OWL DL公理。 相似文献
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本文深入研究了本体的存储介质以及本体在关系数据库中的存储模式,指出当前各种本体存储模式的不足之处,提出了新的基于关系数据库的混合存储模式。用教育领域本体测试框架对所提出的存储模式进行实验验证。实验结果表明,该文所设计的基于关系数据库的存储模式具有结构清楚,查询效率高和扩展性能强的优点。用该文设计的混合存储模式要比目前广泛使用的垂直模式在各方面的性能都更优越,而且也适宜于存储大规模本体。 相似文献
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Integrated access to multiple data sources requires a homogeneous interface provided by a federated schema. Such a federated schema should correctly reflect the semantics of the component schemata of which it is composed. Since the semantics of a database schema is also determined by a set of semantic integrity constraints, a correct schema integration has to deal with integrity constraints existing in the different component schemata. Traditionally, most schema integration approaches solely concentrate on the structural integration of given database schemata. Local integrity constraints are often simply neglected. Their relationship to global extensional assertions, which form the basic integration constraints, are even ignored completely. In this paper, we discuss the impact of global extensional assertions and local integrity constraints on federated schemata. In particular, we point out the correspondence between local integrity constraints and global extensional assertions. The knowledge about the correspondences between the given integrity constraints and extensional assertions can then be utilized for an augmented schema integration process. 相似文献