Developing Geo Ontology Layers for Web Query

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Developing Geo Ontology Layers for Web Query

• Faculty of Design Technology Conference -
  2005-12-07
• David George,
• Department of Computing

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Key Considerations of this Presentation

• The Web The Global Information Space
• Previous data and information integration
  approaches.
• What is an Ontology?
• Semantic Web and Ontology - as method of linking
  (or integrating) data, information and knowledge.
• Research direction Geographical Ontology Layers
  for Application-based Query.

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The Web a Global Information Space

• Graphical representation of World Wide Web around
  Google
• (from Wikipedia, a Web-based free-content
  encyclopaedia)

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Efficient Web Querying?
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Efficient Web Querying?

• Google query for Cook
• results - 130,000,000 English pages
• Google New Zealand
• results - 230,000,000 pages
• Cook New Zealand
• results 38,600,000
• Cook discovered New Zealand
• 950,000
• Cook discovered New Zealand
• 167 English pages

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Historical Integration Approaches
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Historical Characteristics

• Data and information repositories pre-exist and
  invariably heterogeneous in
• Syntax
• Structure
• Semantics
• Integration or mappings are effected
  after-the-event.
• Increasing us of intelligent agents

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Ontologies what are they?

• In Computing - ontology is a formal vocabulary of
  a universe of discourse e.g. medicine,
  geography, ...
• An Ontology defines
• concepts and their attributes.
• relationships between concepts.
• constraints on those relationships.

An Ontology is a formal, explicit specification
of a shared conceptualisation (Gruber, 1993
Borst, 1997)
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Geographical Ontology (extract)
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Semantic Web Characteristics

• Its not here yet! Limited examples of
  implementation e.g. RSS News feeds.
• Focus on mappings of data sources to existing
  resources, e.g. generic, domain and
  application-based ontology structures
• Existing Web data will require monumental
  conversion or exist in parallel.
• Particular relevance in Scientific, Academic,
  Defence, and Commercial enterprises.
• Specialised tools required.

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Semantics on the Web

• Cook discovered New Zealand.
• "Robin Cook" discovered "New Zealand
• 12,000 English pages !!!!
• Semantic Web solution?
• RDF and OWL Ontology technologies
• RDF triple (s,p,o) - based on a binary directed
  relationship.
• Using predicate discovered e.g.
• discovered(Cook, New Zealand)

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Semantic Web Page

• RDF is a graph-based model for describing how
  Internet resources relate to each other (e.g. Web
  pages, email messages, RSS, searches).
• RDF provides a model for metadata, i.e. a
  mechanism for integrating and organising those
  resources.
• RDF/XML is a serialization syntax that allows the
  graph-based model to be communicated between
  "agents".

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WWW and Semantic Web
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Graduate School Scenario
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RDF Example linked resources
RDF/XML Serialisation lt?xml version"1.0"
encoding"iso-8859-1"?gt ltrdfRDF
xmlnsrdf"http//www.w3.org/1999/02/22-rdf-syntax
-ns" xmlnsinfo"http//www.dgeorge.
com/vocabulary/pim/info"gt ltinfoPerson
rdfabout"http//www.uclan.ac.uk/gradschool/conf/
dec05/index.htmDGeorge"gt ltinfofullNamegtDavid
Georgelt/infofullNamegt ltinfomailbox
rdfresource"mailtodgeorge_at_uclan.ac.uk"/gt
ltinfoactivitygtResearch Studentlt/infoactivitygt
ltinfopresentation rdfresource"http//www.ucla
n.ac.uk/gradschool/conf/dec05/George-D-ppt.htm"/gt
lt/infoPersongt lt/rdfRDFgt
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Geographic Ontology Layers
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Geographic Ontology Layers
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Road Transportation Populations
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Road Transportation Populations
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Road Transportation Populations
OWL Ontology Language
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Linked Ontology Layers
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Bibliographic Data Ontology (extract)
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XML and RDF

• XML allows you to invent tags (extensibility)
  that can contain both text data and other tags
• ltDescriptiongtThe value of this property contains
  some text, mixed up with child properties such as
  its temperature (ltTempgt48lt/Tempgt) and longitude
  (ltLonggt101lt/Longgt). lt/Descriptiongt
• XML documents can present weird data structures
  that mix trees, graphs, and character strings. In
  general, these are hard to handle in even
  moderate amounts.
• XML is a vital part of the solution to RDF's
  Interchange design goal as XML is unequalled as
  an exchange format on the Web.
• But by itself, it doesn't provide what you need
  in a metadata framework.

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XML and RDF

• RDF is a framework for describing and
  interchanging metadata, built on these rules
• A Resource is anything that can have a URI this
  includes all the Web's pages, as well as
  individual elements of an XML document.
• A Property is a Resource that has a name and can
  be used as a property, for example Author or
  Title.
• A Statement consists of the combination of a
  Resource, a Property, and a value ('subject',
  'predicate' and 'object). E.g. "The Author of
  http//www.textuality.com/RDF/Why.html is Tim
  Bray." The value can just be a string, for
  example "Tim Bray, or another resource,
  http//www.textuality.com/RDF/author.htmlTimBray
• The RDF would be expressed in XML, e.g.
• ltrdfDescription about'http//www.textuality.com/
  RDF/Why-RDF.html'gt ltAuthorgtTim Braylt/Authorgt
  ltHome-Page rdfresource'http//www.textuality.com
  ' /gt lt/rdfDescriptiongt

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XML Page has author Sid

• ltauthorgt
• lturigtpagelt/urigt
• ltnamegtSidlt/namegt
• lt/authorgt
• or
• ltdocument href"page"gt
• ltauthorgtSidlt/authorgt
• lt/documentgt
• or
• ltdocumentgt
• ltdetailsgt
• lturigthref"page"lt/urigt
• ltauthorgt
• ltnamegtSidlt/namegt
• lt/authorgt
• lt/detailsgt
• lt/documentgt

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XML Page has author Sid

• ltvgt
• ltxgt
• ltygt a"ppppp"lt/ygt
• ltzgt
• ltwgtqqqqqlt/wgt
• lt/zgt
• lt/xgt
• lt/vgt
• It can not be determined whether ppp is a y of
  qqq, or qqq is a z of ppp, or what.
• ltrdfDescription about'http//www.textuality.com/
  RDF/Why-RDF.html'gt ltAuthorgtTim Braylt/Authorgt
• ltHomepage rdfresource'http//www.textuality.com'
  /gt
• lt/rdfDescriptiongt
• Consider that the RDF "description" element
  indicates to the parser how to find the subjects
  and objects that follow.