Simple Knowledge Organisation System SKOS Bliss Classification Association 2005

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Simple Knowledge Organisation SystemSKOSBliss
Classification Association 2005
Semantic Web Best Practices and Deployment
Alistair MilesCCLRC Rutherford Appleton
Laboratory
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The Semantic Web Elephant
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Overview

• SKOS whats it for, and what can it do?
• SKOS where does it fit with all the other bits
  and pieces of the (semantic) web?
• SKOS is a small part of a big picture.

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Requirements

• I want to send my thesaurus/taxonomy/classificatio
  n scheme/subject heading system/controlled
  vocabulary from one database/application to
  another.
• I want to publish my thesaurus/taxonomy/ in an
  electronic form, so that it can become part of
  a distributed information network/environment.

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Goals

• The goals of SKOS Core are
• to provide a simple, machine-understandable,
  representation framework for Knowledge
  Organisation Systems (KOS)
• that has the flexibility and extensibility to
  cope with the variation found in KOS idioms
• that is fully capable of supporting the
  publication and use of KOS within a
  decentralised, distributed, information
  environment such as the world wide (semantic) web.

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Scope

• In scope
• controlled vocabularies
• thesauri
• taxonomies
• classification schemes
• subject heading systems
• Grey area
• terminologies (sensu ISO TC37 SC4)
• wordnets
• lexical databases
• synonym rings
• glossaries
• dictionaries
• ontologies
• folksonomies

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E.g. Thesaurus

• Economic cooperation
• UF Economic co-operation
• SN Includes cooperative measures in banking,
  trade, industry etc., between and among
  countries.
• BT Economic policy
• NT Economic integration
• RT Interdependence

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E.g. Thesaurus
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Features

• SKOS Core allows you to
• identify concepts with URIs
• label concepts with literals (e.g. love_at_en),
  symbols (e.g. ), sounds? other?
• document concepts with definitions, examples,
  scope notes, history notes, editorial notes
• semantically relate concepts
• organise concepts into concept schemes, and into
  smaller meaningful groupings (arrays)
• use concepts to subject-index documents

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Further Reading

• SKOS Core Guide
• http//www.w3.org/TR/swbp-skos-core-guide
• SKOS Core Vocabulary Specification
• http//www.w3.org/TR/swbp-skos-core-spec

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Extensibility FAQ

• Can I extend SKOS Core?
• YES
• How do I do it?
• Proposed draft (includes example extensions for
  fundamental facets and pre-coordinate
  indexing)
• see
• http//www.w3.org/2004/02/skos/core/proposalsexte
  nsion-6
• http//www.w3.org/2004/02/skos/core/proposalscoor
  dination-8

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Development

• SKOS Core development
• open community process
• published through W3C process
• SKOS and BC2
• Develop features for representation of
  analytico-synthetic classification systems
• SKOS discussion forum
• public-esw-thes_at_w3.org post suggestions,
  comments
• mailtopublic-esw-thes-request_at_w3.org?subjectsubs
  cribe

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The Semantic Web Elephant
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The Web Technology Spaghetti
HTTP Hypertext Transfer Protocol
RDF Resource Description Framework
XMLExtensible Markup Language
URI Uniform Resource Identifier
SPARQL RDF Query Language
OWL Web Ontology Language
SKOS Simple Knowledge Organisation System
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Better Meta
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Better Meta

• Google image search aliman

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Better Meta

• Flickr aliman

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Flickr
http//flickr.com/photos/tags/aliman/
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MortenF Photos
http//www.wasab.dk/morten/photos/
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Better Meta

• N.B. we are not talking about bringing order to
  the entire web
• e.g. open directory
• We are talking about communities with a common
  interest bringing order to a part of the web
• e.g. portals, subject gateways

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Sosig
http//www.sosig.ac.uk/
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harpers
http//www.harpers.org/beta/
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SWED
http//www.swed.org.uk
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Better Meta

• How does the technology fit in?
• RDF
• The distributed metadata framework for the web

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Better Meta
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Better Meta

• SKOS
• Application of RDF
• Simple subject- or topic- oriented metadata
• e.g. SWED

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Better Meta

• N.B. SWED portal harvests metadata published by
  the environmental organisations themselves

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A New Type of Content
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Piggybank
http//www.w3.org/People/EM/
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Foafnaut
http//foafnaut.org
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Piggybank
http//citeseer.lcs.mit.edu/ http//simile.mit.ed
u/bank/
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A New Type of Content

• RDF
• Designed for publication of pure information on
  the web
• Hyper-information (cf. hypertext)
• N.B. this allows information to be re-purposed
• SKOS
• Supports publication of a specific type of
  information namely thesauri, classification
  schemes, subject systems, taxonomies
• (cf. e.g. FOAF supports publication of
  information about people)

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A New Type of Content

• Currently published using SKOS
• DDC
• GEMET
• UKAT

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Distributed Data
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Distributed Data
?
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Distributed Data
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Distributed Data
?
SPARQL RDF Query
SKOS, Dublin Core
RDF, URI
BC2
UCL library
Reading Library
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Distributed Data

• "If HTML and the Web made all the online
  documents look like one huge book, RDF, schema,
  and inference languages will make all the data in
  the world look like one huge database."Tim
  Berners-Lee, Weaving the Web, 1999

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Distributed Data

• The (World-Wide) Semantic Web vs.
• A Semantic Web

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Knowledge Representation
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hpdemo
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Knowledge Representation

• Ontologies
• sensu OWL (the web ontology language)
• modelling types of things, and properties of
  things
• e.g. SWED
• support certain types of inference

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Knowledge Representation

• knowledge has logical interrelationships and
  dependencies
• e.g. if I am a Zoologist, I am also a Scientist.
• e.g. if Jenifer is my mother, then she is also
  one of my parents.
• e.g. if an animal eats only vegetation, then it
  is a herbivore.
• e.g. if Liz is my sister, and Holly is Lizs
  daughter, then Holly is my niece.

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protégé
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Knowledge Representation

• Uses of inference
• extensibility and dumb-down
• manage dependencies between information
• management of large, complex ontologies, e.g.
  life sciences

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Knowledge Representation

• OWL and SKOS
• Can use both in combination.
• e.g. SWED
• best of both worlds ?

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The Elephant
Distributed Data
Better Metadata
A New Type of Content
Knowledge Representation
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Thanks

• Thanks a lot, hope to hear from you via
  public-esw-thes_at_w3.org