The aim of this chapter is to present the web ontology language owl which can be used to develop semantic web applications that understand information and data on the web. Web developers can use metadata, which are described in a resource description framework rdf 9 or the web ontology language owl 10 to specify titles, publishers, meanings, and other semantic roles. Owlweb ontology language, including all constructs in this book and more. Web ontology language an overview sciencedirect topics.
The most notable application of dls and owl is in biomedical informatics where dl assists in the codification of biomedical knowledge. Ontologies are a formal way to describe taxonomies and classification networks, essentially defining the structure of knowledge for various domains. Owl web ontology language for services sei digital library. Web, and specialpurposed ontology, such as ebxml that aims to enable enterprises of any size, in any global region, to conduct business using the internet 3. Ontology engineering synthesis lectures on the semantic web. In the other side, the ontologies became the backbone of the semantic web which described formally using a standard language called owl ontology web language. Owl 2 web ontology language primer world wide web consortium.
If the semantic web vision 1 is to be realized, a sound and principled means of representing and reasoning with uncertainty will be required. An owl ontology describes a domain in terms of classes, properties and individuals and may include rich descriptions of the characteristics of those objects. The w3c owl 2 web ontology language owl is a semantic web language designed to represent rich and complex knowledge about things, groups of things, and relations between things. Many dls are more expressive than propositional logic but less expressive than firstorder logic. The web ontology language owl is a lan guage for defining ontologies on the web. The web ontology language is tightly interwoven with the development of.
Pdf the expressivity of rdf and rdf schema that was described in 12 is. Owl is a computational logicbased language such that knowledge expressed in owl can be. One recent unifying effort in creating the ontology language for the web is the web ontology language owl by the world. Owl 2 ontologies provide classes, properties, individuals, and data values and are stored as semantic web documents. More precisely, we can say that an ontology language should be able to express con. Ontology language an overview sciencedirect topics. A number of research groups in both america and europe had already identi ed the need for a more powerful ontology modelling language. Ontology and also the various languages designed for sharing data. Qualitative reasoning and the web ontology language. The development process of the semantic web and web ontology. Web ontology language web ontology working group, 10 february 2004. The web ontology language owl is a family of knowledge representation languages for authoring ontologies.
For example, suppose several different web sites contain medical information or provide medical ecommerce services. Pdf constructing railway ontology using web ontology. This document is also available in these nonnormative formats. Thus, users can customize ontologies to include domain specific information while retaining the interoperability benefits of sharing terminology where possible. The web ontology language owl is a language for defining ontologies on the web. The use of ontologies in this context requires a welldesigned, wellde ned, and web compatible ontology language with supporting reasoning tools. Chapter 4 a semantic web primer 8 reasoning support for owl semantics is a prerequisite for reasoning support formal semantics and reasoning support are usually provided by mapping an ontology language to a known logical formalism using automated reasoners that already exist for those formalisms. Owl facilitates greater machine interpretability of web content than that supported by xml, rdf, and rdf schema rdfs by providing additional vocabulary along with a formal. This language was proposed by the w3c and was designed for publishing, sharing data and automating data understood by computers using ontologies. Ontology languages for the web semantic web effort led to development of resource description language s e. Pdf owl web ontology languageoverview researchgate. Owl 2 web ontology language new features and rationale. Dec 11, 20 the w3c web ontology language owl is a semantic web language designed to represent rich and complex knowledge about things, groups of things, and relations between things. Web ontology languages will be the main carriers of the information that we will want to share and integrate.
Owl ontologies can be used to describe the properties of web. Owl ontology describes a domain in terms of classes, properties and. Currently, users search for data on the web asking. Owl has more facilities for expressing meaning and semantics than xml, rdf, and rdfs, and thus owl goes beyond these languages in its ability to represent machine interpretable content on the web. The owl web ontology language for services owls is a language to describe the properties and capabilities of web services in such a way that the descriptions can be interpreted by a computer system in an automated manner. A web ontology language, that builds on current web languages that allow the specification of. Owls is a markup language based on owl to create computer discoverable web services.
Web of documents processed by humans currently, users search for data on the web asking questions like which documents contain these words or phrases todays web doc 1 doc 4 doc 2 doc 5 doc 3 doc 6. Earlier research on ontology design methodologies shows that manual construction of ontology is a complex process and it is very hard for a designer to develop a consistent ontology. The owl web ontology language is an international standard for encoding and exchanging ontologies and is designed to support the semantic. The semantic web a set of standards for common data formats and exchange protocols extension of web standards resource description framework rdf web ontology language owl sparql protocol and rdf query language sparql. The development process of the semantic web and web. An ontology language is a mean to specify at an abstract level that is, at a conceptual level what is necessarily true in the domain of interest. Ontology languages for the semantic web universidad politecnica. In this chapter we analyse the limitations of rdf schema and derive requirements for a richer web ontology language. In 2004, this working group produced the w3c recommendation owl. It is of particular importance in providing a logical formalism for ontologies and the semantic web.
In order to extend the limited expressiveness of rdf schema, a more expressive web ontology language owl has been defined by the world wide web. Owl 2 ontologies can be used along with information written in rdf. Ontology languages for the semantic web ontology languages. The web ontology language owl extends rdf and rdfs. Next layer web ontology language owl w3c semantic web activity launched, 201. Web ontology language owl introduction to ontologies and. Rdf stands for resource description framework rdf is a framework for describing resources on the web rdf provides a model for data, and a syntax so that independent parties can exchange and use it rdf is designed to be read and understood by computers rdf is not designed for being displayed to.
It is intended to facilitate interpretability among web content using vocabulary and formatting that allows automatic machine processing. Some of them are based on xml syntax, such as ontology exchange language. Web ontology languages will be the main carriers of the information that we will want to. Define an ontology, annote html pages with ontological information to. 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. Web ontology language requirements desirable features identified for web ontology language. This technical note presents the results of applying the model problem approach to examine the feasibility of using owls to. In order to extend the limited expressiveness of rdf schema, a more expressive web ontology language owl has been defined by the world wide web consortium w3c. The book can serve as a course textbook or a primer for all those interested in ontologies. Extends existing web standards such as xml, rdf, rdfs easy to understand and use should be based on familiar kr idioms formally specified of adequate expressive power possible to provide automated reasoning support from. In contrast to the latter, the core reasoning problems for dls are usually decidable, and efficient decision procedures have been designed and implemented for these problems.
The report includes documentation of research on the owls profile. First, in chapter 2 we recapitulate the current state that can be characterised as from markup languages to metadata. Uml is the unified object oriented modeling language which became an important standard. Semantic web, future web, will revolutionize the world with machine knowledge processing capabilities. The ontology web language owl is a set of markup languages which are designed for use by applications that need to process the content of information instead of just presenting information to humans the owl ontology describe the hierarchical organization of ideas in a domain, in a way that can be parsed and understood by software. Web ontology language often stylized as owl is a semantic web language that is designed to process and integrate information over the web, making sense of it in a manner similar to human reasoning. Since then owl served as a backbone for knowledge representation on the web and several inference algorithms for it, in particular for owl dl, were developed and implemented. Ontology is the building block of the semantic web. The owl ontology describe the hierarchical organization of ideas in a domain, in a way that can be parsed and understood by software.
Semantic web exercise sheet 7 owl exercise 1 owl reasoning 7 points. In this exercise we will extend the family ontology by using owl 2 vocabulary. Design an owl dl ontology which models the domain described through a set of natural language statements given below. An introduction and uml profile for the web ontology language. Because it provides additional vocabulary along with a formal semantics, owl facilitates greater machine interpretability of web content than xml, rdf, and rdf schema rdfs. Existing web languages extended to facilitate content. Owl 2 adds expressivity to owl dl without becoming undecidable.
The semantic web 8 is a w3c initiative for integrating and exchanging web resources. An introduction and uml profile for the web ontology. Model problems in technologies for interoperability. Owl is part of the semantic web vision the next generation of the web web 3. Description logics dl are a family of formal knowledge representation languages. Ontology languages several ontology languages have been developed during the last few years, and they will surely become ontology languages in the context of the semantic web. Owl ontologies can be used to describe the properties of web resources. A common feature in ontology languages is the ability to extend preexisting ontologies. Rdf schema rdfs, 32000 updated 402 rdf model theory, 402 rdf xml syntax specification revised, 302 vocabulary layer supports resources, properties, motivated in part by the dublin core. Yyyy semantic web exercise sheet 7 owl exercise 1 owl reasoning 7 points provided with the ontology about people, things and animals explain the following class and. Owl 2 web ontology language document overview second. Owl is a computational logicbased language such that knowledge expressed in owl can be exploited by computer programs, e.
The web ontology language owl is a semantic markup language for publishing and sharing ontologies on the web. The w3c owl 2 web ontology language owl is a semantic web. Web ontology language owl world wide web consortium. To describe the meaningsemantics of the web data rdf is written in terms of owl owl is called an ontology language. Unfortunately, not everything from rdf can be expressed in dl. An introduction to the owl web ontology language department of. Owl has more facilities for expressing meaning and semantics. Mapping uml sequence diagram into the web ontology. Its primary aim is to bring the expressive and reasoning power of description logic to the semantic web. Owl has features from several families of representation languages, including primarily. The syntax of this language should be both intuitive to human users and compatible with existing web standards such as xml, rdf, and rdfs.
Owl is a computational logicbased language such that knowledge expressed in owl can be reasoned with by computer programs. Some of them are based on xml syntax, such as ontology exchange language xol,3 shoe4 which was previously based on html,and ontology markup language oml, 5. Semantic web, and to discuss the formal foundations of these languages. The ontology lies at the core of semantic data integration.
The owl 2 web ontology language, informally owl 2, is an ontology language for the semantic web with formally defined meaning. This book, motivated by the ontology 101 tutorial given for many years at what was originally the semantic technology conference semtech and then later from a semesterlong university class, is designed to provide the foundations for ontology engineering. However, the web ontology working group of w3c3 identi ed a number of characteristic usecases for ontologies on the web which would require much more expressiveness than rdf and rdf schema. The semantic web is based on a set of language such as rdf and owl that can be used to markup the content of web pages. Owl 2 dlsubset of owl restricted to ensure decidability. Introduction to semantic web ontology languages springerlink. Chapter 4 a semantic web primer 8 reasoning support for owl semantics is a prerequisite for reasoning support formal semantics and reasoning support are usually provided by mapping an ontology language to a known logical formalism using automated reasoners that already exist for those formalisms owl is partially mapped on a description logic, and. The basic language to build an ontology is the resource description. If these web sites share and publish the same underlying ontology of the terms they all use, then computer agents can extract and aggregate information from these different sites. For an overview of the new features of owl 2 seeowl 2 web ontology language. Pdf on jan 1, 2004, mcguinness and others published owl web ontology language overview find, read and cite all the research you need on.
The daml program resulted in the web ontology language owl markup as a w3 recommendation. Web consortium w3c standards such as xmls and rdfs, and more recently, the web ontology language owl 35, 45, 2, 39. Apr 14, 2016 the web ontology language owl is a semantic markup language for publishing and sharing ontologies on the world wide web. By adding such metadata, applications handling rdf or owl. Extensible markup language xml, resource description framework rdf and web ontology language owl are the stilts of this technology 2. Description logics as ontology languages for the semantic web. The owl web ontology language for services owls is a language to describe the. Dec 11, 2012 the owl 2 web ontology language, informally owl 2, is an ontology language for the semantic web with formally defined meaning. Description framework rdf and ontology vocabularies, meaning is added to the. The web ontology language owl is the most expressive standard language for modeling ontologies, the cornerstone of the semantic web. The owl web ontology language is a new formal language for representing ontologies in the semantic web. However, up u through its interoperability and reasoning capabilities, the semantic web opens a realm of possibilities for developing intelligent systems on the web. Introduction to semantic web ontology languages department of.
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