Semantic Technology

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Semantic Technology

• supporting science

Peter Mika / Dept. of Computer Science / Vrije
Universiteit, Amsterdam
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Overview

• Two systems
• One technology
• Many possibilities

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flink

• networks in science

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Flink

• Social network data collection, aggregation,
  storage and visualization
• Target the Semantic Web community
• Semantic Web technology
• Ontology-based representation and reasoning
• Try it
• http//flink.semanticweb.org
• Open source (in part)
• Elmo API for Sesame
• http//www.openrdf.org

1st prize _at_ Semantic Web Challenge, 2004
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Presentation and Analysis
Representation, storage and reasoning
Sesame
Sesame
Sesame
Sesame
Data acquisition
FOAF profiles
Web
Emails
Publications
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Browsing
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Subcommunities
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Associations between research topics
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Geographic visualization
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Network analysis
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Network measures vs. status vs. performance
SWWS, ISWC chair (4)
W3C co-chairs (2)
Journal of Web Semantics (4) IEEE Intelligent
Systems (3)
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openacademia

• metadata for the masses

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Metadata micro-management

• Repository for small research groups
• Software you can download and install
• Distributed system (unlike CiteSeer, DBLP)
• Open source
• As easy as
• Maintaining a BibTex/Endnote file for yourself
• Optionally filling out a form to create a
  personal/group profile
• Instant gratification
• For the researcher publication list and RSS feed
  for homepage by adding a ltLINKgt tag and one line
  of JavaScript
• For the group reporting, dissemination on group
  homepage etc.
• http//openacademia.org

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Pimp your homepage
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Query interface
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Applying the BibTex stylesheet
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We got tagclouds!
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And social networks.
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RSS feeds, live bookmarks
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Publication list for homepage
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Architecture
Can be another openacademia server!
Can be remote server!
XSLT transformation to produce to produce HTML,
BibTex etc.
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Semantic technologies
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The benefits modelling aggregation

• Explicit
• RDF/OWL allows to express and reason with what it
  means for two things to be the same (smushing)
• Extendible
• Designed to be distributed both in terms of
  schema and data
• Mappings between different schemas can also be
  expressed in the language
• Flexible
• Mappings can be partial, robustness
• Standard
• Standard languages (RDFS, OWL, SPARQL)
• Standard vocabularies (DC, PRISM, SWRC)
• Standard protocols (SPARQL)

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The drawbacks

• Limited expressivity
• e.g. complex inverse functional properties
• e.g. swrcpage, prismstartingPage and
  prismendingPage
• Ontology-based interchange is still partly social
  engineering
• Scalability

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What about Web 2.0?
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Folksonomies are ontologies

• Large number of individual tagging actions result
  in the emergence of the semantics of tags
• Lightweight, dynamic ontologies
• P. Mika. Ontologies are us A unified model of
  social networks and semantics. In Proceedings of
  the Fourth International Semantic Web Conference
  (ISWC 2005), Yolanda Gil, Enrico Motta, Richard
  V. Benjamins and M. A. Musen (eds.) , Lecture
  Notes in Computer Science no. 3729, page 122-136,
  Galway, Ireland, November, 2005

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Tagging

• Tagging interests in flink, topics of
  publications in openacademia (also Connotea,
  CiteULike, bibsonomy etc.)
• Tag interchange is problematic in general
• flickrajax del.icio.usajax ?
• flickballPeter flickballJohn ?
• flickballPeter1990 flickballPeter2006 ?
• More flexible than controlled vocabularies
• Tracks the evolution of the language better
• Should work for scientific objects (publications,
  presentations etc.)
• Users have the same object in mind when tagging,
  limited community (scientific jargon)

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Blogging, semantic wikis

• openacademia imports comments about publications
• Required blog search (auto-discovery?)
• Semantic wikis are promising
• Metadata directly in RDF
• Syntactic metadata for now (who commented on
  what, what time)

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P2P?
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Example Bibster

• P2P bibliography sharing system
• Each peer has an RDF triple store with
  publication metadata
• Advanced query routing based on semantic models
  of the content and user interests
• Outcome of the EU IST project SWAP and winner of
  a number of awards, featured on Slashdot
• No one uses it.
• Software you install and keep running

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openacademia p2p

• Servers of research groups are networked
• Web-based infrastructure

openacademia.org/ servers.rdf
VUA
Stanford
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p2p spirit

• flink and openacademia can be edited by anyone
• Create descriptions of publications, personal
  metadata, group and event definitions
• Let our crawler find it

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future

• bright

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Trends

• Changing form of publishing
• Demise of the journal as distribution channel
• Community reviewing
• Demise of the journal as quality seal
• The semantic conference
• e.g. ESWC 2006
• In general
• More and more data
• Increased connectedness of data sources
• Productivity

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Who is involved?
Do you still read journals?

• Researchers

Online repositories
Do you still go to the library?