Thesauri, Terminologies and the Semantic Web

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Thesauri, Terminologies and the Semantic Web
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CCLRC

• Council for the Central Laboratory of the
  Research Councils (CCLRC)
• Big Science
• Synchrotron Radiation Sources
• Lasers
• Pulsed Neutron Source
• Large-scale IT demands tera-scale data,
  computation
• Strong IT RD programme
• BITD Business and Information Technology
  Department

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SWAD-E

• Semantic Web Advanced Development for Europe
  (SWAD-E)
• EU Project
• W3C Semantic Web Activity
• RD
• Demos Apps
• Guidelines Best Practises
• Partners HP Labs, ILRT, Stilo, ERCIM (INRIA),
  CCLRC

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Semantic Web

• Current Web
• Web of information for humans
• Semantic Web
• Web of data for computers
• Why?
• Automation, organisation, search
• Enabling technologies
• RDF Resource Description Framework
• Data linking, low-level semantics
• OWL Web Ontology Language
• High-level semantics, inference

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SWAD-E Thesaurus Activity

• Why is SWAD-E interested in thesauri?
• Large body of well-engineered knowledge
• Enrich bootstrap semantic web
• SWAD-E Thesaurus Activity
• Design Schemas for thesaurus data
• Guidelines for use and migration
• Supporting technologies and demos

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Exploiting the Semantic Web

• What can you get out of the semantic web?
• Integration Connectivity
• Data Interoperability
• Application Interoperability
• N.B. The Semantic Web is a Tool.

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Integration Connectivity

• Recurring use-case high/low-level thesauri
• E.g. GCL Cultural Heritage thesauri
• E.g. Gerrys macro/micro thesauri
• RDF gt Data linking
• Can create large linked thesaurus structures
  super-thesauri
• Linking solves problem of concurrent versions

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Data Interoperability

• Interoperability is a major goal
• Move to XML technologies is a step in the right
  direction
• But
• XML does not equal Interoperability
• N.B. plethora of XML formats for thesauri

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SKOS-Core RDF Schema for Thesauri

• Introducing SKOS-Core 1.0
• RDF Schema for Thesauri
• SKOS Simple Knowledge Organisation Systems
• The First Challenge coping with variety in
  thesaurus design and structure
• Allow unique features
• Support interoperability
• The Second Challenge interoperating
  with/migrating to ontologies, taxonomies,
  classification schemes etc.
• N.B. The semantic web is where data collide

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SKOS Meta-Model

• SKOS Meta-Model Concept-orientation
• Concepts (given URIs)
• Labels (pref, alt) (symbols)
• Concept Schemes
• Semantic Relations (extensible set)
• Broader, narrower, related
• Semantic Mappings (extensible set)
• Exact, inexact
• Scope notes, definitions, depictions
• Infer meaning of concept from labels, scope
  notes, definitions, depictions neighbours.

skossemanticRelation
sub-property of
skosbroader
sub-property of
skosbroaderInstantive
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SKOS Meta-Model
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Example GEMET

• Non-Standard Features
• Groups Super-Groups
• Themes
• Solution Extend SKOS-Core
• Class gemetGroup
• Sub-class of skosConcept
• Class gemetTheme
• Sub-class of skosConcept
• Property gemetbroaderTheme
• Sub-property of skosbroader
• Property gemetbroaderGroup
• Sub-propery of skosbroader

skossemanticRelation
sub-property of
skosbroader
sub-property of
gemetbroaderGroup
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Approach to Non-Standard Thesauri

• Design schema as extension to SKOS-Core
• Preserve unique features
• Can interoperate with anything based on
  SKOS-Core
• Have your cake and eat it!

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Example MeSH

• Medical Subject Headings
• Thesaurus features
• Semantically ambiguous concept hierarchy
• Ontology features
• Semantic typing of concepts, e.g. Calcymycin type
  Antibiotic
• Use combination of SKOS and OWL to represent
  this hybrid structure
• RDF, SKOS OWL means you can migrate a thesaurus
  to ontology merely by adding statements
• (No re-engineering or transformation is required)

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Interoperability Thesaurus Mapping

• Common use-case overlapping thesauri
• Mappings support interchangeable use of
  overlapping thesauri
• Introducing SKOS-Mapping
• RDF Schema for inter-thesaurus mapping

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SKOS-Mapping
Sets of Resources in which Concept Occurs
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Data Interop Summary

• SKOS-Core supports interoperability of KOS with
  variable structures
• SKOS-Mapping supports interoperability of
  overlapping KOS

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Multilinguality

• Analyse multilingual thesaurus into language
  components
• Multilingual Labelling
• Use SKOS-Core
• E.g. GEMET
• Inter-lingual Mapping
• Use SKOS-Core SKOS-Mapping
• E.g. AAT, Merimee

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Multilinguality (2)
Analyse each language component
Multilingual Labelling
Interlingual Mapping
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Application Interoperability

• Move to modularisation and distribution via web
  services is step in the right direction
• But
• Web services does not equal application
  interoperability
• Web service API
• Community driven design
• Endorsed by wider community

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SKOS API

• SKOS API
• Interface to terminology web service
• Under development (pre-release is online)
• Participate on public mailing list
• public-esw-thes_at_w3.org

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Web Service Implementation

• Reference Implementation of SKOS API
• Leverage power of sem-web tools
• E.g. RDF Query
• E.g. transitive closure of broader concepts
• SOAP Service
• Back end Sesame RDF Store
• Modular design
• Semantic Web Services

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Future Issues

• Social aspects
• Semantic web technology supports community driven
  development of thesauri
• But validation?
• Change Management
• Versioning
• Evolution

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Summary

• Semantic Web Technologies are tools
• SKOS-Core SKOS-Mapping support data
  interoperability
• SKOS API supports application interoperability
• W3C Semantic Web Best Practises Working Group
• Thesaurus Task Force

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SWAD-E Eco-informatics

• Work with thesaurus developers and managers
• Publish RDF encodings of current thesauri
• Test design and coverage of SKOS-Core
• Community building for development of web service
  API

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Thank You

• Links
• SWAD-Europe Thesaurus Activity
• http//www.w3.org/2001/sw/Europe/reports/thes/
• SKOS-Core 1.0 Guide
• http//www.w3.org/2001/sw/Europe/reports/thes/1.0
  /guide/
• SKOS API
• http//www.w3.org/2001/sw/Europe/reports/thes/sko
  sapi.html
• SKOS-Core 1.0 Guidelines for Migration
• http//www.w3.org/2001/sw/Europe/reports/thes/1.0
  /migrate/
• Public Thesaurus Mailing list
• public-esw-thes_at_w3.org
• W3C Semantic Web Activity
• http//www.w3.org/2001/sw/
• SWAD-E Project
• http//www.w3.org/2001/sw/Europe/