RDF and the Semantic Web -- Joanna PszenicynPresentation Transcript
RDF and the Semantic WebRDF and the Semantic WebJoanna PszenicynJoanna Pszenicyn
What we already know● RDF is a resource description that computerscan “understand”● RDF uses XML● Like XML, it is a metalanguage(defines syntax only, not semantics)● RDF & OWL (Web Ontology Language)are building blocks for the Semantic Web
Semantic Web“The Semantic Web is a mesh of informationlinked up in such a way as to be easilyprocessable by machines, on a global scale.You can think of it as being an efficient way ofrepresenting data on the WWW, or as a globallylinked database.”Sean Palmer, The Semantic Web: an Introduction
Semantic Web and AI● Now:● Specialized programs“wise” only in a narrowfield● Someday maybe:● Global net ofinterlinked data● Programs which“hope to make sense”of any data theyencounter
RDF TriplesSubject – Predicate – ObjectorEntity – Attribute – ValueExample:Sky – has the color – blue
Namespaces● One RDF document can contain data in severalschemes● It is possible to combine Dublin Core withMarcXML● Or FOAF (Friend of a Friend)
Examples● VIAF – Virtual Authority File:http://viaf.org/● LoC Linked Data Service:http://id.loc.gov/
Pros & ConsPros: Anything that facilitates the interchangeof metadata is a good thing. RDF is a flexibleand extensible framework that could potentiallybe used in a wide variety of applications. Itfacilitates interoperability between Web-basedapplications involving the exchange ofmachine-readable information.
Pros & ConsCons: Some have described the syntax asclunky, and physically ugly to look at. There isrelatively limited tool support at this time,compared to what is available for, say, plainvanilla XML. At least one XML guru feels that thelevel of abstraction is so high that RDF is all butunusable by the vast majority of developers. (See"RDF and other monkey wrenches" by SeanMcGrath, http://www.itworld.com/nl/ebiz%5fent/03182003.)Kennedy, Shirl. 2004. RDF. Computers in Libraries
BibliographyBerners-Lee, Tim; James Hendler, and Ora Lassila. 2001.The Semantic Web. Scientific American 2001 (5).Gradmann, Stefan. 2005. rdfs:frbr--Towards an Implementation Model for Library Catalogs Using Semantic Web Technology.Cataloging & Classification Quarterly. 2005, Vol. 39 Issue 3/4, p. 63–75.Jul, Erik. MARC and Mark-Up. Cataloging & Classification Quarterly.2003, Vol. 36 Issue 3/4, p.141.Kennedy, Shirl. 2004. RDF. Computers in Libraries, 2004, Vol. 24,Issue 2.McGrath, Sean. 2003. RDF and other monkey wrenches. ITworld.Available at:http://www.itworld.com/nl/ebiz_ent/03182003Singer, Ross. Linked Library Data Now! Journal of ElectronicResources Librarianship. 2009, Vol. 21, Issue 2, p. 114–126.
Thank YouThank YouFor Your AttentionFor Your AttentionJoanna PszenicynJoanna Pszenicynj.email@example.com@student.uw.edu.pl