1 / 14

Semantic Web

Semantic Web. Lecture Notes Prepared by Jagdish S. Gangolly Ph.D Program in Information Science State University of New York at Albany. Semantic Web.

lawrence-bullock
Download Presentation

Semantic Web

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Semantic Web Lecture Notes Prepared by Jagdish S. Gangolly Ph.D Program in Information Science State University of New York at Albany Inf 703, Fall 2003 (Gangolly)

  2. Semantic Web • ..is a mesh of information linked up in such a way as to be easily processable by machines, on a global scale. (http://infomesh.net/2001/swintro/) Inf 703, Fall 2003 (Gangolly)

  3. Motivation • Need for interchangeability of information (information sharing) • Need for interchangeability, translatability, uniformity of ontologies • Need for improving precision in retrieval • Need for web services based on understanding of data as well as metadata Inf 703, Fall 2003 (Gangolly)

  4. Semantic Web Components • Data • Structure • Content • Format • Ontology • Metadata • Representation Languages • Facility for metadata Interchange Inf 703, Fall 2003 (Gangolly)

  5. Data • Data (Semi-structured as well as structured) • Structure Tags: XML-Schema • Content Tags: XML-Schema • Ontology: Ontology representation languages Inf 703, Fall 2003 (Gangolly)

  6. Metadata I • Representation languages based on First Order Logic • KIF-based Ontolingua (http://www.ksl.stanford.edu/software/ontolingua/ • Loom (http://www.isi.edu/isd/LOOM/LOOM-HOME.html) • Frame-Logic (http://www.cs.sunysb.edu/~kifer/dood/papers.html) Inf 703, Fall 2003 (Gangolly)

  7. Metadata II • Languages using standardised syntax • Simple HTML Ontology Extensions (SHOE) (http://www.cs.umd.edu/projects/plus/SHOE/) • XOL Ontology Exchange Language (XOL)(http://www.ai.sri.com/pkarp/xol/) • Ontology Markup Language (OML and CKML) (Ontology Markup Language (OML and CKML) • Resource Description Framework Schema Language (RDFS) (http://www.w3.org/TR/rdf-schema/) • RiboWEB (http://www-smi.stanford.edu/projects/helix/riboweb/kb-pub.html) Inf 703, Fall 2003 (Gangolly)

  8. Metadata III • OIL (Ontology Interchange Language) (http://www.ontoknowledge.org/oil/) • DAML+OIL (http://www.daml.org) • XFML+CAMEL (eXchangeable Faceted Metadata Language + Compound term composition Algebraically-Motivated Expression Language) (http://www.csi.forth.gr/~tzitzik/XFML+CAMEL/) • Good sources of information: http://www.cs.umd.edu/users/hendler/sciam/walkthru.html http://www.semanticweb.org/knowmarkup.html (These notes based on this source) Inf 703, Fall 2003 (Gangolly)

  9. Dublin Core • Metadata ElementsISO 15836:2003 Inf 703, Fall 2003 (Gangolly)

  10. RDF (http://www.xml.com/pub/a/2002/01/30/daml1.html) • XML based language that allows you to define classes and properties <rdfs:Class rdf:ID="Product"> <rdfs:label>Product</rdfs:label> <rdfs:comment>An item sold by Super Sports Inc.</rdfs:comment> </rdfs:Class> <rdfs:Property rdf:ID="productNumber"> <rdfs:label>Product Number</rdfs:label> <rdfs:domain rdf:resource="#Product"/> <rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Literal"/> </rdfs:Property> Inf 703, Fall 2003 (Gangolly)

  11. DAML+OIL I(http://www.xml.com/pub/a/2002/01/30/daml1.html) • DAML+OIL also allows you to define instances of classes and specify their properties <Product rdf:ID="WaterBottle"> <rdfs:label>Water Bottle</rdfs:label> <productNumber>38267</productNumber> </Product> • DAML+OIL allows datatyping <daml:DatatypeProperty rdf:ID="productNumber"> <rdfs:label>Product Number</rdfs:label> <rdfs:domain rdf:resource="#Product"/> <rdfs:range rdf:resource="http://www.w3.org/2000/10/XMLSchema#nonNegativeInteger"/> </daml:DatatypeProperty> Inf 703, Fall 2003 (Gangolly)

  12. DAML+OIL II(http://www.xml.com/pub/a/2002/01/30/daml1.html) • Provides for uniqueness, equivalence, enumerations, disjoint classes, disjoint unions of classes, non-exclusive Boolean combinations of classes, intersection of classes, sub-classing, property restrictions • Rich enough to model ontologies Inf 703, Fall 2003 (Gangolly)

  13. Web Ontology Language (OWL) I • OWL Lite supports those users primarily needing a classification hierarchy and simple constraints. • OWL DL supports those users who want the maximum expressiveness while retaining computational completeness (all conclusions are guaranteed to be computed) and decidability (all computations will finish in finite time). • OWL Full is meant for users who want maximum expressiveness and the syntactic freedom of RDF with no computational guarantees. Source: http://www.w3.org/TR/owl-features/ Inf 703, Fall 2003 (Gangolly)

  14. Web Ontology Language (OWL) II Inf 703, Fall 2003 (Gangolly)

More Related