Thesauri, Terminologies and the Semantic Web A J Miles Rutherford Appleton Laboratory CCLRC • Council for the Central Laboratory of the Research Councils (CCLRC) • Big.
Download ReportTranscript Thesauri, Terminologies and the Semantic Web A J Miles Rutherford Appleton Laboratory CCLRC • Council for the Central Laboratory of the Research Councils (CCLRC) • Big.
Thesauri, Terminologies and the Semantic Web A J Miles Rutherford Appleton Laboratory 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 A J Miles 22 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 A J Miles 33 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 A J Miles 44 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 A J Miles 55 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. A J Miles 66 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 – superthesauri Linking solves problem of concurrent versions A J Miles 77 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] A J Miles 88 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 A J Miles 99 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 skos:semanticRelation sub-property of skos:broader sub-property of skos:broaderInstantive Infer meaning of concept from labels, scope notes, definitions, depictions & neighbours. A J Miles 10 10 SKOS Meta-Model A J Miles 11 11 Example: GEMET • Non-Standard Features: – Groups & Super-Groups – Themes • Solution: Extend SKOS-Core: – Class gemet:Group • Sub-class of skos:Concept – Class gemet:Theme • Sub-class of skos:Concept – Property gemet:broaderTheme • Sub-property of skos:broader – Property gemet:broaderGroup • Sub-propery of skos:broader A J Miles skos:semanticRelation sub-property of skos:broader sub-property of gemet:broaderGroup 12 12 Approach to Non-Standard Thesauri • Design schema as extension to SKOSCore Preserve unique features Can interoperate with anything based on SKOS-Core Have your cake and eat it! A J Miles 13 13 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) A J Miles 14 14 Interoperability: Thesaurus Mapping • Common use-case: overlapping thesauri – Mappings support interchangeable use of overlapping thesauri • Introducing: SKOS-Mapping – RDF Schema for inter-thesaurus mapping A J Miles 15 15 SKOS-Mapping Sets of Resources in which Concept Occurs Exact Inexact Major Minor Partial Broad Narrow Ordered Combinators: A J Miles AND, OR, NOT 16 16 Data Interop Summary • SKOS-Core supports interoperability of KOS with variable structures • SKOS-Mapping supports interoperability of overlapping KOS A J Miles 17 17 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 A J Miles 18 18 Multilinguality (2) Analyse each language component Multilingual Labelling Interlingual Mapping A J Miles 19 19 GEMET Backbone in SKOS-RDF <skos:Concept rdf:about="c_3194"> <gemet:broaderTheme rdf:resource="t_9"/> <skos:narrower rdf:resource="c_1824"/> <skos:narrower rdf:resource="c_13150"/> <skos:narrower rdf:resource="c_13260"/> <skos:narrower rdf:resource="c_13177"/> <skos:narrower rdf:resource="c_13152"/> <skos:narrower rdf:resource="c_8308"/> <skos:inScheme rdf:resource="../GEMET"/> <skos:narrower rdf:resource="c_6793"/> <gemet:broaderGroup rdf:resource="g_2504"/> <skos:narrower rdf:resource="c_3205"/> <skos:narrower rdf:resource="c_1025"/> <skos:narrower rdf:resource="c_13151"/> <skos:narrower rdf:resource="c_11044"/> <skos:narrower rdf:resource="c_3201"/> <skos:narrower rdf:resource="c_4478"/> <skos:narrower rdf:resource="c_6602"/> </skos:Concept> A J Miles 20 20 GEMET en labels in SKOS-RDF <skos:Concept rdf:about="c_3194"> <skos:prefLabel xml:lang="en-GB">finances</skos:prefLabel> <skos:definition xml:lang="en-GB">The monetary resources or revenue of a government, company, organization or individual. (Source: RHW)</skos:definition> </skos:Concept> A J Miles 21 21 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 A J Miles 22 22 SKOS API • SKOS API – Interface to terminology web service – Under development (pre-release is online) • Participate on public mailing list: [email protected] A J Miles 23 23 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 A J Miles 24 24 Future Issues • Social aspects – Semantic web technology supports community driven development of thesauri – But … validation? • Change Management – Versioning – Evolution A J Miles 25 25 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 A J Miles 26 26 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 A J Miles 27 27 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/skosapi.html SKOS-Core 1.0 Guidelines for Migration http://www.w3.org/2001/sw/Europe/reports/thes/1.0/migrate/ Public Thesaurus Mailing list [email protected] W3C Semantic Web Activity http://www.w3.org/2001/sw/ SWAD-E Project http://www.w3.org/2001/sw/Europe/ A J Miles 28 28