Towards an Interlinked Semantic Wiki Farm
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Transcript of Towards an Interlinked Semantic Wiki Farm
Alexandre Passant1,2, Philippe Laublet1
1 LaLIC, Université Paris-Sorbonne2 EDF, Recherche & Développement
Towards an Interlinked Semantic Wiki FarmSemWiki2008 - ESWCJune 2, 2008
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2
Social software at EDF R&D
• Electricité de France R&D• The largest electricity company in France• More than 2000 researchers in its R&D department• Lots of different people: chemists, trading experts, computer
scientists ...• Informal and closed-world communities
• “Knowledge = Power”, due to its cultural history
• Enterprise 2.0 and EDF R&D• 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
• Find ways to let people more easily exchange information and build knowledge collaboratively
• Introducing new tools and principles• Blogs, RSS feeds, tagging, wikis• Top-down vs bottom-up approach
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Using Wikis at EDF R&D
• Users adopted wikis for their particular needs, as people do on the Web
• Internal project management• Corporate information• Knowledge bases on scientific topics• ...
• Usage statistics• More than 1000 registered users for the whole platform• About 50 wikis, 2800 pages, 60 active users• Different wikis as some people want “their” wiki• Closed, read-only and open wikis, depending on the communities• 10% radio between consumers and producers (blogs included)• Many people were not used to those Web 2.0 principles
• Both technically and regarding the cultural changes it implies regarding knowledge management
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Technical limits of wikis for knowledge management
• 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”• “Who’s working on tidal energies ?”
• 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 modeling knowledge• The Semantic Web bridges this gap and semantic wikis provide
ways to achieve this
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From documents to resources
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Existing semantic wikis
• Using wikis to model data using Semanitic Web principles• Ontology population and instances evolution• Adding RDF into wiki pages
• SemperWiki• Extending wiki syntax to define annotations
• Semantic MediaWiki• Assisting users with user-friendly interfaces
• IkeWiki, OntoWiki
• Using Semantic Web principles to enrich the usage of wikis• Organizing tags to enhance information retrieval
• SweetWiki
• Powerful (querying, reasoning, enhanced navigation ...), but raise usability issues in a corporate context
• URIs, namespaces, triples...• People need something that work without aditional efforts
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UfoWiki: Unifying Forms and Ontologies in a Wiki
• A semantic wiki-farm server• Goals
• Provide a user-friendly interface to let users create ontology instances and manage them in the wiki way
• Hidden semantics for end-users, using forms• Use SIOC and MOAT to model wiki pages meta-data, so that it can
be integrated with other internal SIOC data• A corporate SIOC-o-sphere
• Connect the meta-data layer to the data (i.e. content) layer• Who wrote facts about EDF ?
• Reuse RDF data available on the Web• Geonames.org, DBpedia ...
• Interlink data from various wiki instances• While some wikis are private, their data is valuable
• Re-use semantic annotations to provide value added interfaces• Macros, semantic search-engine
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A form-based user interface
• Using forms to maintain ontology instances• Let end-users focus on the content rather than on the modeling• Avoid semantic heterogeneity
• Wiki administrators define form-based page templates• Based on existing Drupal modules
• Flexinode (Drupal4), rewriting to CCK• Each page corresponds to an ontology class
• Organization page => foaf:Organization• Each field corresponds to a property or relationship
• Some complex fields can be used to define internal instances• Some fields can be used to define MOAT tags
• Ease the process of linking tagged content to related instances• E.g. acronym, nickname
• SPARQL autocompletion based on expected class type• Closing the open-world assumption, inference might come later
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Using wiki to manage ontology instances
• Each created page yields to one main instance, and related / internal ones
Macro interne
Champ avec auto-complétion
Instance interne
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Linking data and meta-data
• embedsKnowledge: linking a sioc:Item to a graph containing the triples that were create from this sioc:Item
• Using SIOC Types module for meta-data modeling• sioct:WikiArticle rdfs:subClassOf sioc:Item
athena:EDF
http://sws.geonames.org/3017382geonames:locatedIn
Wiki page A
embedsKnowledge
sioct:WikiArticle
rdf:type
sioc:has_creator
http:://athena/alex
dc:title
EDF
Meta-data RDF file
Data RDF file
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Architecture of a single wiki
Semantic Web layer
Document layer(wiki level)
Wiki page
A
RDF
description
of objects
embedded
in page A
RDF
meta-data
about page
A
Wiki page
B
RDF
description
of objects
embedded
in page B
RDF
meta-data
about page
B
HTML hyperlink
produces
producesproduces produces
Semanticrelationships
between objects
semantic linksemantic link
User 1
User 2
RDF Store
edit
edit
Storage
Meta-data ontologies
(SIOC, DC ...)
Data-modelingontologies
(SKOS, Domain ontologies ...)
uses
uses
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Interlinking data from various wikis
• All wikis share a common knowledge base• URI identification across wikis• Merge statements about URIs but keep source using named graphs
athena:EDF
http://sws.geonames.org/3017382
geonames:locatedIn
Wiki page A
embedsKnowledge
athena:EDF
athena:NuclearEnergy
athena:produces
Wiki page B
embedsKnowledge
RDF Backend
sioct:WikiArticle
sioct:WikiArticle
rdf:type
rdf:type
athena:EDFgeonames:locatedIn
http://sws.geonames.org/3017382 athena:NuclearEnergy
athena:produces
stores stores
merges
Wiki A
Wiki B
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Using produced RDF data
• RDF data is exported to the triple-store when page is created• Immediately re-usable and up-to-date data
• Inline macros• Defined by wiki administrators, using PHP and SPARQL• User-friendly syntax to let end-users embed it in wiki pages
• Eg: [onto|members], [onto|type,foaf:Person]• Can be used to run complex queries about data from another wiki
• Eg: All activities of an company and related organizations
• Direct RDF querying• Advanced users - User-friendly SPARQL interface planned• Queries regarding data, meta-data or both
• Semantic search• From keyword to concept• Integration with other SIOC data
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Macro results
• SPARQL query results in wiki pages• Subject of the query is the currently browsed instance• Similar to SemanticMediaWiki inline macros• Semantic back-links
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SPARQL-ing RDF data from the wiki
• Combining meta-data and content levels:• All pages from the wiki #6 that provide information about EDF and
than have at least 2 repliesselect ?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> ;
sioc:num_replies ?replies .
<http://example.org/wiki/6> a sioct:Wiki .
} FILTER (?replies > 1)
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Reusing RDF data available on the Web
• The Linking Open Data initiative• Lots or RDF data available from reference data-sets• 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 to geonames.org web-service• Retrieve the location URI and its related RDF file (with coordinates)• Simple way to create geolocation services and enhance navigation• Provide interlinked RDF data
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Easy-geolocation with our GeoNames wrapper
• Combining geolocation and macro-queries• Location of any member of the currently browsed organization
• [onto|mapmembers] => SPARQL + rendering
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Querying the internal SIOC-o-sphere
• Combining SIOC-based information from various data sources • Find relevant resource from given keyword with MOAT• Retrieves main / related wiki pages from different wikis• Retrieve “tagged” blog posts
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Conclusion
• Overview of our approach• User-friendly interface with forms mapped to ontologies• SIOC-based meta-data to ease integration with existing SIOC data• Combining meta-data and data (content) layer• Interlinking data from various wiki instances• Using existing RDF data and vocabularies for value-added service
• What’s next ?• Validate forms using the underlying ontologies• User-interface to define macros• Linking / reusing more LOD data• Use SIOC in other wikis as a meta-data model