It also shows how to use an owl ontology with swrl rules from java code by calling a reasoner. The pd semantics 37 is a precursor for owl2rl and for work on supporting owl through horn fragments. Pharmacogenomic knowledge representation, reasoning and. This is especially important in regards to the web because it offers the hope of organizing the web by meanings, not just by matching strings of characters. All created using daz 3d studio software and my warped, twisted imagination. To this end, we recall the relationship between owl and description logics dls, and show how each of the profiles is typically treated in reasoning algorithms. Its primary aim is to bring the expressive and reasoning power of description logic to the semantic web. Web ontology language owl is an ontology language designed for the semantic web it provides a rich collection of operators for forming concept descriptions it is a w3c standard, promoting interoperation and. Practical experience with owl has been quite positive in general. An introduction to the owl web ontology language 3 concepts such as boolean combinations of classes and property restrictions.
Owl facilitates greater machine interpretability of web content than that supported by xml, rdf, and rdf schema rdfs by providing. It presents the core features of the basic formal ontology bfo, now used by over one hundred ontology projects around the world, and offers examples of domain ontologies that utilize bfo. It will enable users and software agents to automatically discover, invoke, compose, and monitor web resources. University of dublin trinity college introduction to web ontology language owl owen. About owl 2 web ontology language xml serialization joinup.
Citeseerx document details isaac councill, lee giles, pradeep teregowda. An introduction and uml profile for the web ontology. Published at reasoning web 2012 book chapter download pdf last update. Pharmacogenomic knowledge representation, reasoning and genomebased clinical decision support based on owl 2 dl ontologies. In this work, we follow the latter approach, by identifying the syntactic differences that a fuzzy ontology language has to cope with, and by proposing a concrete methodology to represent fuzzy ontologies using owl 2 annotation properties.
Since achieving w3c recommendation status in 2004, the web ontology language owl has been successfully applied to many problems in computer science. Owl or web ontology language is the ontology think schema language of the semantic web. Reasoning in the owl 2 full ontology language using first. This page explains the web ontology language owl 2 to us who are visually oriented. Owl 2 owl 2, became a w3c recommendation in 27 october 2009.
An ontology language for the semantic web which is extended from owl 1 and empowered by new features. In owl 2, there are three sublanguages of the language. They cover rdf schema, web ontology language owl, rules, and query languages, such as sparql. Compared to owl dl as a whole, reasoning algorithms for the owl profiles show. Owl is a computational logicbased language such that knowledge expressed in owl can be exploited by computer programs, e. Owl was especially designed for creating web ontologies with a rich set of modeling constructors, addressing the ontology engineering limitations of. It is known that the owl 2 rl web ontology language profile has ptime data complexity and can be translated into datalog. An introduction and uml profile for the web ontology language owl october 23, 2002 elisa f.
This specification serves as the bibliographic ontology namespace document. A large number of ontologies have been developed for the annotation of biological and biomedical data, commonly expressed in the web ontology language owl or an owl compatible language such as the obo flatfile format. Owl has features from several families of representation languages, including primarily. The owl web ontology language is designed for use by applications that need to process the content of information instead of just presenting information to humans. The reason is that, when translated into datalog, the result may consist of a datalog program and a. Although the uo is directly developed in the obo flatfile format, a software tool generates several different owl versions that are suitable for different application scenarios.
Uo is available in both the obo flatfile format and the web ontology language owl. An introduction to lightweight ontology languages reasoning web summer school 2012, 112183, september 2012. Owl 2 web ontology language quick reference guide 1 namespaces. Therefore, a knowledge base in owl 2 rl may be unsatisfiable. This chapter describes concepts related to the support for a subset of the web ontology language owl. Owl web ontology language erdogan dogdu notes from semantic web for the working ontologist book property characteristics inverse symmetric transitive. The most expressive of these languages is owl 2 full, but to date no reasoner has been implemented for this language. Web ontology language owl semantics for example, we can state in our ontology. The three ontology language standards are sublanguages of owl dl that are restricted in ways that significantly simplify ontological reasoning.
The owl family of languages supports a variety of syntaxes. One of the main tools for this is owl, an ontology computer language. Owl web ontology language part 2 erdogan dogdu notes from semantic web for the working ontologist book restriction defining classes in terms of other classes a class defined by describing the individuals it contains a description of its members in terms of existing properties and classes. In reality, there is a fine line where the ontology ends and the knowledge base begins. The web ontology language owl has been a w3c recommendation 34 since 2004, with owl 2 43 re. Owl 2 ql is designed to enable easier access and query to data stored in databases.
For an owl 2 dl ontology, there are some global restrictions on axioms. In computer science, an ontology is a description of knowledge about a domain of interest, the core of which is a machineprocessable speci. The document describes the syntaxes for owl 2, the different kinds of semantics, the available sublanguages, and the relationship between owl 1 and owl 2. Bibliographic ontology specification the bibliographic. Consistency and entailment checking are known to be undecidable for owl 2 full.
Section 5 focuses on the interrelationship of owl documents, particularly with respect to importing and versioning. The web ontology language owl is a language for defining ontologies on the web. The owl web ontology language is a new formal language for representing ontologies in the semantic web. Ontology structure picture taken from owl 2 web ontology language rdfbased semantics second edition an ontology together with a set of individual instances of classes constitutes a knowledge base. Owl 2 web ontology language profiles second edition. A number of horn fragments of dls with ptime data complexity have also been investigated in 5,15,19,21,23,31,32,35. It is one of the core semantic web standards you must be familiar with, along with rdf and sparql. Since owl became a world w3c wide web consortium recommendation, there has been a steady stream of web owl ontology language ontology editing tools that have made their way to users desktops. Web ontology language owl world wide web consortium. As such it describes the bibliographic ontology and the terms rdf classes and properties that constitute it, so that semantic web applications can use those terms in a variety of rdfcompatible document formats and applications.
Compared to owl dl as a whole, reasoning algorithms for the owl profiles show higher performance, are easier to implement, and can scale to larger amounts of data. Pascal hitzler, markus kroetzsch, sebastian rudolph. It builds on the information in chapter 1, and it assumes that you are familiar with the major concepts associated with owl, such as. Owl s is an ontology, within the owl based framework of the semantic web, for describing semantic web services. The owl 2 language is not able to express all relations. We developed web ontology language owl ontologies and automated reasoning methodologies to meet the following goals. Owl 2 has been standardized by the world wide web consortium w3c as a family of ontology languages for the semantic web. Web ontology language owl introduction to ontologies and. Access to the full extent of knowledge contained in ontologies is facilitated by automated reasoners that can compute the.
Ontologies and frameworks semantic web and linked data. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as semantic web documents. The book also describes web ontology language owl, a common framework for semantic web technologies. Owl has features from several families of representation languages. Owl 2 ontologies can be used along with information written in rdf, and owl 2 ontologies themselves. The conversion tool is freely available on uos website. Owl ontology is a set of axioms, which provide explicit logical assertions about three types of things. Citeseerx on the web ontology rule language owl 2 rl. The owl 2 web ontology language, informally owl 2, is an ontology language for the semantic web with formally defined meaning.
However, the result of translation may consist of a datalog program and a set of constraints in the form of negative clauses. Science, services and agents on the world wide web, 64. The web ontology language owl extends rdf and rdfs. For example, the classes of classes are not permitted in the chosen dl, and some of the triple expressions would have no. Some drawings can be done in a day some take weeks and are ongoing. Owl ontologies can be used to describe the properties of web resources. The reason is that, when translated into datalog, the result may consist of a datalog program and a set of constraints in the. Owl documents, known as ontologies, can be published in the world wide web and may refer to or be referred from other owl ontologies. An owl ontology describes a domain in terms of classes, properties and individuals and may include rich descriptions of the characteristics of those objects. On the web ontology rule language owl 2 rl 3 some extensions of dhl were considered in 30.
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