The Syntactic and the Semantic Web By Jorge Cardoso

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The Syntactic and the Semantic WebBy Jorge
Cardoso

• CMPT 455/826 - Week 6, Day 1

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XML and RDF

• XML can apply to any chunk of text.
• What types of data can RDF apply to?

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Resources

• What types of resources does RDF apply to

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OWL

• How does OWL relate to RDF?

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What about the old/new Web?

• What are the expectations regarding existing
  pages, i.e. will they be upgraded to become
  semantic Web pages?
• What are the expectations regarding new pages,
  i.e. will they all be semantic Web pages?

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Single vs. Multiple Ontologies

• Discuss
• "The more specific, detailed and complex you make
  your ontology, the more semantic value it has.
• But then, it will make it harder to integrate
  with other Semantic Web ontologies because the
  syntaxes of different ontologies are not likely
  to be the same.
• As noted by David Weinberger

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Multiple Ontologies

• When you combine multiple ontologies, it is
  possible that you will create contradictions or
  ambiguities.
• How can/should we deal with this?
• Is a merged super-ontology the answer?

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Exacting Semantics

• Google matches terms based on words as tokens
  without considering their semantics. This can be
  good and can be problematic.
• Discuss what happens if we want to be more
  precise?

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Automatic Tagging

• The chapter assumes that developers will create
  the appropriate semantic tags.
• Discuss the possibilities of automatic tagging.
• Discuss the possible problems with automatic
  tagging.

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Issues

• Discuss what could be done about?
• instances of uncertainty
• instances of inconsistency
• instances of deceit
• instances of relative / context specific data
• instances of opinions / facts
• instances of time specific data

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What about Proof and Trust?

• Proof and Trust are not elaborated. Provide some
  suggestions for how they might be dealt with

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Now for some stuff from the Chapter

• The following slides are taken from the chapter

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Levels of Semantics
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Semantic Web Architecture
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e.g. XML

• XML uses developer created descriptors
• ltContact contact_id"1234"gt
• ltfirst_namegt Jorge lt/first_namegt
• ltlast_namegt Cardoso lt/last_namegt
• ltorganizationgt University of Madeira
  lt/organizationgt
• ltemailgt jcardoso_at_uma.pt lt/emailgt
• ltphonegt 351 291 705 156 lt/phonegt
• lt/Contactgt

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e.g. RDF

• RDF uses semantic descriptors defined in an
  ontology
• lt? xml version"1.0" ?gt
• ltRDF xmlns "http//w3.org/TR/1999/PR-rdf-syntax-
  19990105" xmlnsDC "http//dublincore.org/2003
  /03/24/ dces"gt
• ltDescription about "http//dme.uma.pt/jcar-
  doso/"gt
• ltDCCreatorgt Jorge Cardoso lt/DCCreatorgt
• lt/Descriptiongt
• lt/RDFgt

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e.g. OWL

• OWL creates descriptors and rules used by RDF
• ltowlAllDifferentgt
• ltowldistinctMembers rdfparse Type"Collection"gt
  
• ltadminAdministrator rdfabout"Web designer"/gt
• ltadminAdministrator rdfabout"Editor"/gt
• ltadminAdministrator rdfabout"Graphic
  designer"/gt
• lt/owldistinctMembersgt
• lt/owlAIIDifferentgt