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Ian Horrocks - One of the best experts on this subject based on the ideXlab platform.
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Owl 2 web ontology language mapping to rdf graphs
2009Co-Authors: Peter F Patelschneider, Bernardo Cuenca Grau, Ian HorrocksAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents. This document defines the mapping of Owl 2 ontologies into RDF graphs, and vice versa.
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Owl 2 web ontology language structural specification and functional style syntax
2008Co-Authors: Boris Motik, Ian Horrocks, Bijan Parsia, Peter F Patelschneider, C Bock, Achille Fokoue, Peter Haase, Rinke Hoekstra, Alan Ruttenberg, Ulrike SattlerAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents. The meaningful constructs provided by Owl 2 are defined in terms of their structure. As well, a functional-style syntax is defined for these constructs, with examples and informal descriptions. One can reason with Owl 2 ontologies under either the RDF-Based Semantics [Owl 2 RDF-Based Semantics] or the Direct Semantics [Owl 2 Direct Semantics]. If certain restrictions on Owl 2 ontologies are satisfied and the ontology is in Owl 2 DL, reasoning under the Direct Semantics can be implemented using techniques well known in the literature.
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Owl 2: The next step for Owl
Journal of Web Semantics, 2008Co-Authors: Bernardo Cuenca Grau, Peter Patel-schneider, Ian Horrocks, Boris Motik, Bijan Parsia, Ulrike SattlerAbstract:Since achieving W3C recommendation status in 2004, the Web Ontology Language (Owl) has been successfully applied to many problems in computer science. Practical experience with Owl has been quite positive in general; however, it has also revealed room for improvement in several areas. We systematically analyze the identified shortcomings of Owl, such as expressivity issues, problems with its syntaxes, and deficiencies in the definition of Owl species. Furthermore, we present an overview of Owl 2-an extension to and revision of Owl that is currently being developed within the W3C Owl Working Group. Many aspects of Owl have been thoroughly reengineered in Owl 2, thus producing a robust platform for future development of the language.
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D2.5.5 Next Steps for Owl
2006Co-Authors: Bernardo Cuenca Grau, Peter Patel-schneider, Ian Horrocks, Bijan Parsia, Ulrike Sattler, Rob ShearerAbstract:EU-IST Network of Excellence (NoE) IST-2004-507482 KWEB Deliverable D2.5.5 (WP2.5) Owl 1.1 is a simple extension to the Owl DL species of the W3C Owl Web Ontology Language. Owl 1.1 has been designed to provide some interesting and useful expressive additions to Owl DL while retaining the desirable characteristics of Owl DL, including decidability and implementability. Keyword list: description logics, ontology language, RDF, Owl DL, Owl, W3C, standardization
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OwlED - Problems with Owl Syntax.
2006Co-Authors: Boris Motik, Ian HorrocksAbstract:In this paper we discuss three problems with Owl syntax that repeatedly surface in practice. The first problem is that Owl does not allow for explicit declarations—assertions that a certain class, property, or an individual exists in an ontology. This aspect of the Owl standard was often misinterpreted, which caused design errors in Owl APIs; moreover, the lack of declarations makes devising an intuitive structural consistency check for Owl ontologies difficult. The second problem is that Owl Abstract Syntax and Owl RDF syntax rely on the separation between object and data property names for disambiguation. We show that this prevents an unambiguous interpretation of certain syntactically well-formed Owl ontologies; furthermore, it makes implementing Owl parsers unnecessarily difficult. The third problem is that Owl Abstract Syntax cannot be translated into Owl RDF syntax without loss of information. We present possible solutions to these three problems, which, if adopted in Owl 1.1, would lead to a cleaner standard and would significantly simplify the implementation of Owl APIs.
Bijan Parsia - One of the best experts on this subject based on the ideXlab platform.
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Owl 2 web ontology language primer second edition
2012Co-Authors: Pascal Hitzler, Bijan Parsia, Peter F Patelschneider, Markus Krotzsch, Sebastian RudolphAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents.
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OwlED - A syntax for rules in Owl 2
2009Co-Authors: Birte Glimm, Bijan Parsia, Matthew Horridge, Peter Patel-schneiderAbstract:Being able to extend an Owl ontology with some form of rules is a feature that many ontology developers consider as very important. Nevertheless, working with rules in practice can be difficult since the tool support is not as good as for handling standard ontologies. Furthermore, the existing rule syntaxes are not very well aligned with the new Owl 2 standard. We propose, therefore, an extension to Owl 2 for representing rules, which is directly inspired by (DL Safe) SWRL rules, but uses and extends the succinct and human-readable functional-style syntax of Owl 2. We also propose an Owl/XML version of the syntax for easy XML serialization. Support for parsing such rules has been added to the new Owl API 3.0 and reasoning support is available in the two Owl 2 reasoners Pellet and HermiT. In HermiT, these rules can also be used in conjunction with description graphs.
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Owl 2 web ontology language structural specification and functional style syntax
2008Co-Authors: Boris Motik, Ian Horrocks, Bijan Parsia, Peter F Patelschneider, C Bock, Achille Fokoue, Peter Haase, Rinke Hoekstra, Alan Ruttenberg, Ulrike SattlerAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents. The meaningful constructs provided by Owl 2 are defined in terms of their structure. As well, a functional-style syntax is defined for these constructs, with examples and informal descriptions. One can reason with Owl 2 ontologies under either the RDF-Based Semantics [Owl 2 RDF-Based Semantics] or the Direct Semantics [Owl 2 Direct Semantics]. If certain restrictions on Owl 2 ontologies are satisfied and the ontology is in Owl 2 DL, reasoning under the Direct Semantics can be implemented using techniques well known in the literature.
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Owl 2: The next step for Owl
Journal of Web Semantics, 2008Co-Authors: Bernardo Cuenca Grau, Peter Patel-schneider, Ian Horrocks, Boris Motik, Bijan Parsia, Ulrike SattlerAbstract:Since achieving W3C recommendation status in 2004, the Web Ontology Language (Owl) has been successfully applied to many problems in computer science. Practical experience with Owl has been quite positive in general; however, it has also revealed room for improvement in several areas. We systematically analyze the identified shortcomings of Owl, such as expressivity issues, problems with its syntaxes, and deficiencies in the definition of Owl species. Furthermore, we present an overview of Owl 2-an extension to and revision of Owl that is currently being developed within the W3C Owl Working Group. Many aspects of Owl have been thoroughly reengineered in Owl 2, thus producing a robust platform for future development of the language.
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OwlED - Literate, Active Owl Ontologies
2008Co-Authors: Bijan ParsiaAbstract:Owl ontologies are complex computational artifacts that are intimately connected with conceptual information and with application issues that are not easily explicable in the context of an Owl document. In this paper, drawing inspiration from literate programming and active essays, I propose a new form of narratively oriented, interactive Owl document. The basic technique has been applied to the draft version of the Owl 2 primer.
Peter F Patelschneider - One of the best experts on this subject based on the ideXlab platform.
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Owl 2 web ontology language primer second edition
2012Co-Authors: Pascal Hitzler, Bijan Parsia, Peter F Patelschneider, Markus Krotzsch, Sebastian RudolphAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents.
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Owl 2 web ontology language rdf based semantics
2009Co-Authors: Jeremy J Carroll, I Herman, Peter F PatelschneiderAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents. This document defines the RDF-compatible model-theoretic semantics of Owl 2.
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Owl 2 web ontology language mapping to rdf graphs
2009Co-Authors: Peter F Patelschneider, Bernardo Cuenca Grau, Ian HorrocksAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents. This document defines the mapping of Owl 2 ontologies into RDF graphs, and vice versa.
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Owl 2 web ontology language
2009Co-Authors: Manchester Syntax, Matthew Horridge, Peter F PatelschneiderAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents. The Manchester syntax is a user-friendly compact syntax for Owl 2 ontologies; it is frame-based, as opposed to the axiom-based other syntaxes for Owl 2. The Manchester Syntax is used in the Owl 2 Primer, and this document provides the language used there. It is expected that tools will extend the Manchester Syntax for their own purposes, and tool builders may collaboratively extend the common language.
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Owl 2 web ontology language structural specification and functional style syntax
2008Co-Authors: Boris Motik, Ian Horrocks, Bijan Parsia, Peter F Patelschneider, C Bock, Achille Fokoue, Peter Haase, Rinke Hoekstra, Alan Ruttenberg, Ulrike SattlerAbstract:The Owl 2 Web Ontology Language, informally Owl 2, is an ontology language for the Semantic Web with formally defined meaning. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. Owl 2 ontologies can be used along with information written in RDF, and Owl 2 ontologies themselves are primarily exchanged as RDF documents. The Owl 2 Document Overview describes the overall state of Owl 2, and should be read before other Owl 2 documents. The meaningful constructs provided by Owl 2 are defined in terms of their structure. As well, a functional-style syntax is defined for these constructs, with examples and informal descriptions. One can reason with Owl 2 ontologies under either the RDF-Based Semantics [Owl 2 RDF-Based Semantics] or the Direct Semantics [Owl 2 Direct Semantics]. If certain restrictions on Owl 2 ontologies are satisfied and the ontology is in Owl 2 DL, reasoning under the Direct Semantics can be implemented using techniques well known in the literature.
John R Speakman - One of the best experts on this subject based on the ideXlab platform.
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mice that are resistant to diet induced weight loss have greater food anticipatory activity and altered melanocortin 3 receptor mc3r and dopamine receptor 2 d2 gene expression
Hormones and Behavior, 2015Co-Authors: Lobke M Vaanholt, Sharon E Mitchell, Rachel Sinclair, John R SpeakmanAbstract:Abstract Diet-induced weight loss varies considerably between individuals, but the mechanisms driving these individual differences remain largely unknown. Here we investigated whether key neuropeptides involved in the regulation of energy balance or reward systems were differentially expressed in mice that were prone or resistant to caloric restriction (CR) induced weight loss. Mice (n = 30 males and n = 34 females) were fed 70% of their own baseline ad libitum intake for 25 days, after which their brains were collected and expression of various neuropeptides were investigated and compared between the 10 male and 10 female mice that showed the greatest (high weight loss, HWL) or lowest weight loss (LWL) (n = 40 in total). HWL mice showed a differential neuropeptide profile to LWL in both sexes, characterised by increased expression of neuropeptide Y (NPY), agouti-related peptide (AgRP), leptin receptor (ObRb), and melanocortin 3 receptor (MC3R) in the arcuate nucleus. No changes in the expression of fat mass and obesity related gene (FTO) or suppressor of cytokine signalling 3 (Socs3) were observed. Levels of dopamine D2 receptor were decreased in the nucleus accumbens in HWL compared to LWL mice. HWL mice showed a stronger increase in food anticipatory activity (FAA) in response to CR than LWL mice. These results indicate that the mice prone to diet-induced weight loss experienced greater hunger, potentially driving their elevated FAA.
Evren Sirin - One of the best experts on this subject based on the ideXlab platform.
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OwlED - Terp: Syntax for Owl-friendly SPARQL Queries.
2010Co-Authors: Evren Sirin, Blazej Bulka, Michael SmithAbstract:Web Ontology Language (Owl) [5] can be seen as an extension of Resource Description Framework (RDF). The primary exchange syntax for Owl is RDF/XML, and every Owl ontology can be represented as an RDF graph. But there is no standard query language specifically for Owl ontologies. The most commonly used Semantic Web query language is SPARQL [7], which is intended to be used for RDF. Roughly speaking, SPARQL is specified as queries matching RDF graphs with simple RDF entailment. However, it allows this definition to be extended to Owl entailment. A semantics for SPARQL compatible with Owl DL has been defined in SPARQL-DL [8] and a similar formalization of Owl-compatible SPARQL semantics is being developed by the W3C’s SPARQL Working Group as part of SPARQL 1.1. The semantics extension of SPARQL allows one to query Owl ontologies and get the expected results with respect to Owl entailments. However, writing SPARQL queries that involve complex Owl expressions ranges from challenging to unpleasant because SPARQL query syntax is based on Turtle [1], which isn’t intended for Owl. SPARQL queries against Owl data have to encode the RDF serialization of Owl expressions: these queries are typically verbose, difficult to write, and difficult to understand. In this paper we present Terp, a new syntax that combines Turtle and Manchester syntaxes to provide maximum legibility and conciseness when querying Owl with SPARQL. More precisely, Terp syntax allows class, property, and data range expressions, expressed in Manchester syntax, to be used inside SPARQL queries. In this paper, we provide examples to demonstrate how Terp reuses existing features from well-known syntaxes to make SPARQL queries of Owl data more concise and more legible.
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pellet a practical Owl dl reasoner
Journal of Web Semantics, 2007Co-Authors: Evren Sirin, Bernardo Cuenca Grau, Bijan Parsia, Aditya Kalyanpur, Yarden KatzAbstract:In this paper, we present a brief overview of Pellet: a complete Owl-DL reasoner with acceptable to very good performance, extensive middleware, and a number of unique features. Pellet is the first sound and complete Owl-DL reasoner with extensive support for reasoning with individuals (including nominal support and conjunctive query), user-defined datatypes, and debugging support for ontologies. It implements several extensions to Owl-DL including a combination formalism for Owl-DL ontologies, a non-monotonic operator, and preliminary support for Owl/Rule hybrid reasoning. Pellet is written in Java and is open source.
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OwlED - SPARQL-DL: SPARQL Query for Owl-DL
2007Co-Authors: Evren Sirin, Bijan ParsiaAbstract:There are many query languages (QLs) that can be used to query RDF and Owl ontologies but neither type is satisfactory for querying Owl-DL ontologies. RDF-based QLs (RDQL, SeRQL, SPARQL) are harder to give a semantics w.r.t. Owl-DL and are more powerful than what Owl-DL reasoners can provide. DL-based QLs (DIG ask queries, nRQL) have clear semantics but are not powerful enough in the general case. In this paper we describe SPARQL-DL, a substantial subset of SPARQL for which we provide a clear Owl-DL based semantics. SPARQL-DL is significantly more expressive than existing DL QLs (by allowing mixed TBox/RBox/ABox queries) and can still be implemented without too much effort on top of existing Owl-DL reasoners. We discuss design decisions and practical issues that arise for defining SPARQL-DL and report about our preliminary prototype implemented on top of Owl-DL reasoner Pellet.
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sparql dl sparql query for Owl dl
OWL: Experiences and Directions, 2007Co-Authors: Evren Sirin, Bijan ParsiaAbstract:There are many query languages (QLs) that can be used to query RDF and Owl ontologies but neither type is satisfactory for querying Owl-DL ontologies. RDF-based QLs (RDQL, SeRQL, SPARQL) are harder to give a semantics w.r.t. Owl-DL and are more powerful than what Owl-DL reasoners can provide. DL-based QLs (DIG ask queries, nRQL) have clear semantics but are not powerful enough in the general case. In this paper we describe SPARQL-DL, a substantial subset of SPARQL for which we provide a clear Owl-DL based semantics. SPARQL-DL is significantly more expressive than existing DL QLs (by allowing mixed TBox/RBox/ABox queries) and can still be implemented without too much effort on top of existing Owl-DL reasoners. We discuss design decisions and practical issues that arise for defining SPARQL-DL and report about our preliminary prototype implemented on top of Owl-DL reasoner Pellet.
