2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria1

Combining structure and semantics for ontology-based corporate wikis

11th International Conference on Business Information SystemsBIS 2008 - Innsbruck, Austria 5-7 May 2008

Alexandre Passant1,2 & Philippe Laublet2

1Electricité de France R&D, Clamart, France2LaLIC, Université Paris-Sorbonne, France

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria2

Wikis for corporate knowledge management

• “Enterprise 2.0 is the use of emergent social software platforms within companies, or between companies and their partners or customers”, Andrew McAfee, May 2006• Blogs, Wikis, RSS feeds, Social Networking, Microblogging …

• New ways to open and share knowledge in corporate environments• Implies social and cultural changes• Bottom-up, top-down or combined approaches

• Wikis offer a powerful way to collaboratively build knowledge• Collective Intelligence - “We are smarter than me”• Open-editing, back-links, versioning …• Various ways to adopt it: project management, knowledge base ...

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria3

Wikis and information retrieval

• Wikis search-engines can only answer plain-text queries• Natural Language Processing algorithms must be applied to extract

information from current wiki systems• Cannot answer questions about the content of wiki pages

• “Is EDF located in France ?”• “List all companies known in that wiki”

• Wikis manage documents, not machine-readable representations of real-world objects

• Documents and hyperlinks instead of resources, relationships and properties

• A gap between these two ways of knowledge representation

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria4

The gap between documents and resources

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Overview of the Semantic Web

• “The Semantic Web is an extension of the current web in which information is given well-defined meaning, better enabling computers and people to work in cooperation” - Tim Berners-Lee, James Hendler, Ora Lassila, Scientific American, May 2001• A common model to describe data in a machine-readable way:

• URIs and RDF (Resource Description Framework)• RDF statements are triples (subject predicate object):

• Common semantics for this data, using ontologies:• “An ontology is a specification of a conceptualization” - Tom Gruber, 1992• RDFS (RDF Schema) and OWL (Web Ontology Language)

• A layer of machine-understandable data over the document one• “Global Giant Graph” - Tim Berners-Lee, Nov. 2007• Interlinked data

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria6

Towards a Social Semantic Web

• Semantic Web and Web 2.0 must not be seen as competitors but could benefit from each other to lead to a better Web, providing socially-created data defined in a machine-understandable way• Many examples

• Vocabularies: FOAF to describe people, SIOC for their data • Authoring tools: Semantic wikis, semantic blogging• Services: Revyu, Dbpedia mobile• Tagging: Tag Ontology, SCOT, MOAT• Journal Of Web Semantics - Special Issue on Web 2.0, 2008

• “I think we could have both Semantic Web technology supporting online communities, but at the same time also online communities can support Semantic Web data by being the sources of people voluntarily connecting things together.” Tim Berners-Lee, ISWC2005 podcast

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria7

The Semantic Web for better wikis (1/2)

• Using wikis to maintain Semantic Web resources • Direct annotation of wiki pages

• Semantic MediaWiki, SemperWiki• Combining wiki pages and triples-based forms

• IkeWiki, Platypus• Complete ontology instances editor

• OntoWiki• Using Semantic Web technologies to improve wikis

• Tag wiki pages and organize tags• SweetWiki

• Model discussion pages in RDF• IkeWiki

• Other approaches• Extracting RDF data from existing wikis

• DBpedia

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria8

The Semantic Web for better wikis (2/2)

• Advanced navigation• Suggest similar pages (e.g. same instances)

• Semantic search and advanced queries• Search by class or property• SPARQL or user-friendly interface• Rendering results in wiki pages

• Reasoning• RDFS or OWL inferencing

• Advanced views• Maps, calendar view

• An active research field, lots of systems and prototypes• SemWiki workshop @ ESWC2008, Tenerife, 2nd of June 2008

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria9

A Semantic wiki-farm at EDF R&D

• Main requirements of the wiki-farm system• Ontology-based knowledge representation

• Avoid semantic heterogeneity• Ability to write pre-defined queries

• Usability• “Hidden Semantics”: End-users must not have to deal with RDF

modeling and Semantic Web principles• Form-based templates

• Combination of data and meta-data modeling• Ability to query both pages meta-data and their content• Share data between various wikis and keep trace of each statement

• Immediate reuse of formalized data• Show the immediate benefit of the approach• Motivate users to contribute

• Our own system: UfoWiki• Unifying Forms and Ontologies in a Wiki• Easy ontology population

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria10

Global architecture

• Ontologies• Modeling content: Domain ontologies, SKOS …

• Depends on the knowledge field of the wiki• Modeling meta-data: SIOC - http://sioc-project.org

• types module: Wiki, WikiArticle…• W3C Member Submission (June 2007)

• Defined an embedsKnowledge property to model links between data and meta-data

• Interface• Admin interface to create forms and define mappings with ontologies

• 1 form = 1 ontology class and related properties• Define widgets to share common form parts between classes

• User interface to create wikis and wiki pages• Triple-store

• Central storage system for data from any wiki • Using SPARQL / SPARUL as an abstraction layer

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria11

Architecture overview

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria12

Managing ontology instances in wiki pages

• Combining plain-text and forms when creating a wiki page• 1 form-based wiki page = 1 instance of the related class• Forms fields are used to manage properties and relationships

• Usability features• WYSIWYG textareas• Autocompletion fields

• Live SPARQL queries to get instances of a given type and interlink data• Creating complex instances type in wiki pages

• Most wikis allow only to create relationships with existing instances• Our system allows users to create complex instances (i.e. with properties

or relationships) within a wiki page• Eg: Role(Domain, Type, Location)

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria13

Editing a wiki page

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Merging RDF data from various pages and wikis

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria15

Reusing RDF knowledge

• RDF data is exported to the triple-store as soon as the page is saved• Immediately re-usable and up-to-date• Merged with existing statements, from any wiki page and any wiki

• Inline macros• Defined by wiki administrators, using PHP and SPARQL• User-friendly syntax for end-users to embed it in wiki pages

• Eg: [onto|members], [onto|type,foaf:Person]• Inline macros can be used to run complex queries

• Eg: All activities of an company and related organizations• From backlinks to semantic-backlinks

• Direct RDF querying• Advanced users• Queries regarding data, meta-data or both• User-friendly SPARQL interface planned

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria16

Inline macros example

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria17

Advanced SPARQL querying

select ?page ?title

where {

graph ?data {

:EDF ?predicate ?object

} .

?page :embedsKnowledge ?data ;

rdf:type sioct:WikiArticle ;

dc:title ?title ;

sioc:has_container <http://example.org/wiki/6> .

<http://example.org/wiki/6> a sioct:Wiki .

}

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria18

Reuing RDF data available on the Web

• The Linking Open Data initiative• Lots or RDF data available from reference datasets• GeoNames, DBpedia, riese …

• Using the same ontologies in a corporate environment• Low-cost integration• No need to align vocabularies and define mapping between them

• GeoNames wrapper• “city, (state), country” fields mapped with geonames.org webservice• Retrieve RDF data for the location and add it in the triplestore• Simple way to create geolocation services and enhance navigation• Provide interlinked RDF between the wiki and existing data

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria19

Easy-geolocation with a GeoNames wrapper

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria20

UfoWiki in use at EDF R&D

• Most users never used wikis before• More than 200 instances and 1000 triples without any knowledge of

RDF• Lots of interlinked data that enhance navigation capabilities

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria21

Future works

• New use cases• Extend the benefits of our system and face new issues to improve it

• Semantic versioning• Archive RDF data from any page to browse evolution of given resource

• Ontology-based form validation• Using OWL axioms (e.g: cardinality, disjunction)

• New ways to browse data• Faceted browsing (e.g: Exhibit)

• Interlinking and reusing other datasets• DBpedia …

• Using SIOC in other Semantic Wikis• Wikis can be part of the SIOC-o-sphere

2008.05.05 Combining structure and semantics for ontology-based corporate wikis - BIS2008, Innsbruck, Austria

Summary

• Wikis are useful for open and collaborative knowledge management in organizations

• But lack of machine-readable data• Plain-text queries only

• The Semantic Web can help• From documents and hyperlinks to resources and relationships• Common model, common semantics• Web 2.0 + Semantic Web = Social Semantic Web

• UfoWiki• Yet another semantic wiki• Usability - using forms to manage ontology instances• Interlinked data - from various wikis, from various pages• Reusing external resources - low-cost data integration• Enhanced browsing and querying capabilities of the system

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Thank you ! / Questions

slides @ http://apassant.net