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The Semantic Web

The Semantic Web. The Next Evolution of the WWW. Chris Whitehead Assistant Professor Columbus State University ACM Mid-Southeast 2008. Overview. What is the Semantic Web? Background Components of the Semantic Web Why the Semantic Web is needed Uses of the Semantic Web

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The Semantic Web

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  1. The Semantic Web The Next Evolution of the WWW Chris WhiteheadAssistant ProfessorColumbus State University ACM Mid-Southeast 2008

  2. Overview • What is the Semantic Web? • Background • Components of the Semantic Web • Why the Semantic Web is needed • Uses of the Semantic Web • Implementing the Semantic Web • Examples • Conclusion

  3. What is the Semantic Web? The Semantic Web is "an extended web of machine-readable information and automated services that amplify the Web far beyond current capabilities" (Daconta et al., 2003) • A framework that: • Adds meaning to data • Provides a mechanism for organizing, interpreting, and making use of that meaning

  4. What is the Semantic Web? (cont) • An enhancement to the current Web, not a replacement “The Semantic Web will bring structure to the meaningful content of Web pages, creating an environment where software agents roaming from page to page can readily carry out sophisticated tasks for users” (Berners-Lee et al., 2001)

  5. Background • 1968 – Internet used as a communications network by DOD • 1989 – Tim Berners-Lee (and others) at CERN develop HTML from SGML • Early 1990s – Web browsers created to interpret HTML • 1996 – XML developed • 1990s+ – Tim Berners-Lee & W3C continue to pursue development the Semantic Web

  6. Components of the Semantic Web • Four major components: • XML • Resource Description Framework (RDF) • Ontologies • Agents

  7. Supplemental Components of the Semantic Web • Supplemental components • Uniform Resource Identifiers (URIs) • Web services • Inference rules • Service discovery • Semantic aware applications • Security and trust • XML and RDF schemas

  8. XML • HTML (XHTML) is a series of predefined tags that add presentation to data <b>This text is bold</b> • XML is a series of user-defined tags that add information and structure to data <author>John Smith</author>

  9. XML (cont) "XML has become the universal syntax for exchanging data between organizations" (Daconta et al., 2003) • Issue: • Some mechanism must exist for coordinating the meaning of the user-defined tags and for understanding the context of that information Company A: <name>Smith</name> Company B: <employee>Jones</employee> Company C: <name>Williams</name>

  10. Resource Description Framework (RDF) • An XML-based language used to describe resources • Resources can include entities, concepts, properties and relations • Captures the meta data about the “externals” of a document • Can use a serialized model, RDF triplets, special notation, or graphs to describe data

  11. Object Predicate Subject Literal Predicate Resource Description Framework (RDF) (cont) • Example serialized model • RDF triplet (subject, predicate, object/literal): Software sells Company Microsoft Is named The company sells software The company is named Microsoft John Smith is the president of Company X Next

  12. <?xml version='l.0' encoding='ISO-8859-1'?> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-na#" xmlns:rdfs="http://www.w3.org/TR/1999/PR-rdf-schema-19990303#" xmlns:s0="http://wr7w.w3.org/2000/PhotoRDF/dc-1-0#" xmlns:sl="http://sophia.inria.fr/-enerbonn/rdfpiclang#" xmlns:s2="http://www.w3.org/2000/PhotoRDF/technical-l-0#"> <rdf:Description rdf:about=”http://www.c2i2.com/~budstv/images/shopl.jpg"> <s0:relation>part-of Store Front</s0:relation> <s0:type>image</s0:type> <s0:format>image/jpeg</s0:format> <sl:xmllang>en</sl:xrnllang> <s0:description>Buddy Belden's work bench for TV/VCR repair</s0:description> <s2:camera>Kodak EasyShare</s2:camera> <s0:title>TV Shop repair bench</s0:title> </rdf:Description> </rdf:RDF> Source: The Semantic Web, Dacaonta, Obrst, & Smith (2003) Back

  13. Ontologies “the common words and concepts (the meaning) used to describe and represent an area of knowledge" (Daconta et al., 2003) • Provide the repositories for meaning interpretations • Provide a mechanism for defining the relationship among different words and for the Semantic Web, relationships among different resources

  14. Ontologies (cont) • Consist of: • Taxonomies • “An organized set of terms.” (McComb, 2004) • A classification and a tree (Daconta et al., 2003) • Hierarchal, tree-like structures similar to organizational charts • Example • Sets of inference rules • Used to organize semantics Next

  15. Taxonomy Example Back

  16. Agents • Also known as software agents • Provide automation services • Should not be designed to replace humans or to make decisions • Examples: Web spiders and crawlers

  17. Supplemental Components of the Semantic Web • Uniform Resource Identifiers (URIs) • Provide a mechanism for identifying available resources • The super-set of URNs, URLs and URCs • Web services • Allow computer applications to communicate directly with each other over the Internet • Inference rules • Define the relationships and rules between data

  18. Supplemental Components of the Semantic Web (cont) • Service discovery • Allows applications to find ontologies and agents • Semantic aware applications • Applications that can make use of semantic information • Security and trust • XML schema • Define the structure of XML documents • Standardizes the communication between systems • RDF schema or OWL • Can be used to define the language used in ontologies and RDFs

  19. Why the Semantic Web is Needed • The current Web remains largely unstructured (e.g., company) • Large amounts of information remain unavailable

  20. Uses of the Semantic Web • Improve e-business processes • Improve business-to-business (B2B) communication • “assist human users in their day-to-day online activities” (Antoniou & van Harmelen, 2004) • “build knowledge and understanding from raw data” (Daconta et al., 2003) • Improve knowledge management • Improve information retrieval • Automate tasking • Integrate data • Maximize customer value and profits

  21. Implementing the Semantic Web • Convert data to XML format according to defined XML schemas • Expose applications as Web services • Build ontologies that specify semantic meanings and the relationships between data • Create agents that make use of the semantic data, automate search processes, and automate other business processes

  22. Issues Concerned with Implementing the Semantic Web • Cost • Security • Nonstandard technology issues • Semantic precision

  23. Examples • http://www.foaf-project.org/ • http://www.cs.rpi.edu/~hendler/ • http://www.mindswap.org/ • http://www.daml.ri.cmu.edu/ • http://www.semanticwebsearch.com/query/

  24. Conclusion • What is the Semantic Web? • Background • Components of the Semantic Web • Why the Semantic Web is needed • Uses of the Semantic Web • Implementing the Semantic Web • Issues concerned with implementing the Semantic Web • Examples Questions?

  25. References • Antoniou, G., & van Harmelen, F. (2004). A semantic Web primer. Cambridge, MA: The MIT press. • Athauda, R. I. (2000). Integration and querying of heterogeneous, autonomous, distributed database systems (Vol. 61/06, pp. 3126): Florida International University. • Berners-Lee, T., Hendler, J., & Lassila, O. (2001). The Semantic Web. Scientific American, 284(5), 34-43. • Carey, P., & Kemper, M. (2003). New perspectives on creating Web pages with HTML and Dynamic HTML (2nd ed.). Boston: Course Technology. • Daconta, M. C., Obrst, L. J., & Smith, K. T. (2003). The Semantic Web: A guide to the future of XML, Web services, and knowledge management. Indianapolis, IN: Wiley Publishing, Inc. • Ewalt, D. M. (2002, October 14). Semantic Web. InformationWeek, 35-44. • Galitz, W. O. (2002). The essential guide to user interface design. New York: John Wiley & Sons, Inc.

  26. References • Gould, M. (1996). Rules in the virtual society. International Review of Law, Computers & Technology, 10(2), 199-218. • Kalakota, R., & Robinson, M. (2001). e-Business 2.0: Roadmap for success. Upper Saddle River, NJ: Addison-Wesley. • Lexico Publishing Group, L. (2004). Inference. Retrieved December 7, 2004, from http://dictionary.reference.com/search?q=inference • McComb, D. (2004). Semantics in business systems: The savvy manager's guide. San Francisco, CA: Morgan Kaufmann Publishers. • Tiwana, A. (2002). The knowledge management toolkit. Upper Saddle River, NJ: Prentice Hall PTR. • Warren, P. (2003). The next steps for the WWW: Putting meaning into the Web. Computing & Control Engineering, 14(2), 27-31. • Young, M. J. (2002). XML step by step (2nd ed.). Redmond, WA: Microsoft Press.

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