1. Thesauri, Terminologies and the Semantic Web

2. 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 R&D programme
BITD: Business and Information Technology Department

3. SWAD-E Semantic Web Advanced Development for Europe (SWAD-E)
EU Project
W3C Semantic Web Activity
R&D
Demos & Apps
Guidelines & Best Practises
Partners: HP Labs, ILRT, Stilo, ERCIM (INRIA), CCLRC

4. Semantic Web Current Web: Semantic Web: Why? Enabling technologies:
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

5. 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

6. 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.

7. Integration & Connectivity
Recurring use-case: high/low-level thesauri
E.g. GCL & Cultural Heritage thesauri
E.g. Gerry’s macro/micro thesauri
RDF => Data linking
Can create large linked thesaurus structures – super-thesauri
Linking solves problem of concurrent versions

8. 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]

9. 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

10. 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.
skos:semanticRelation
sub-property of
skos:broader
sub-property of
skos:broaderInstantive

11. SKOS Meta-Model

12. Example: GEMET Non-Standard Features: Solution: Extend SKOS-Core:
Groups & Super-Groups
Themes
Solution: Extend SKOS-Core:
Class gemet:Group
Sub-class of skos:Concept
Class gemet:Theme
Property gemet:broaderTheme
Sub-property of skos:broader
Property gemet:broaderGroup
Sub-propery of skos:broader
skos:semanticRelation
sub-property of
skos:broader
sub-property of
gemet:broaderGroup

13. 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!

14. 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)

15. Interoperability: Thesaurus Mapping
Common use-case: overlapping thesauri
Mappings support interchangeable use of overlapping thesauri
Introducing: SKOS-Mapping
RDF Schema for inter-thesaurus mapping

16. SKOS-Mapping Sets of Resources in which Concept Occurs Exact Inexact
Major
Minor
Partial
Broad
Narrow
Ordered
Combinators: AND, OR, NOT

17. Data Interop Summary
SKOS-Core supports interoperability of KOS with variable structures
SKOS-Mapping supports interoperability of overlapping KOS

18. 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

19. Multilinguality (2) Analyse each language component
Multilingual Labelling
Interlingual Mapping

20. 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

21. SKOS API SKOS API Participate on public mailing list:
Interface to terminology web service
Under development (pre-release is online)
Participate on public mailing list:

22. 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

23. Future Issues Social aspects Change Management
Semantic web technology supports community driven development of thesauri
But … validation?
Change Management
Versioning
Evolution

24. 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

25. 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

26. Thank You Links: SWAD-Europe Thesaurus Activity
SKOS-Core 1.0 Guide
SKOS API
SKOS-Core 1.0 Guidelines for Migration
Public Thesaurus Mailing list
W3C Semantic Web Activity
SWAD-E Project