Flink:%20Lessons%20of%20interoperability

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Flink Lessons of interoperability

• Peter Mika
• Dept. of Business Informatics
• Free University Amsterdam
• http//www.cs.vu.nl/pmika/
• 1st Intl. Workshop on
• Interoperability of SW portals

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Content

• Flink
• Interoperability
• Flink Interoperability

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What is Flink?

• Flink is a directory of Semantic Web research
• Browse the social network of all authors at ISWC
  01-04
• Profiles with personal information, emails,
  publications
• View statistics
• Download profiles in FOAF format
• Export for Social Network Analysis
• Demonstration of latest SW technology
• 1st prize at the Semantic Web Challenge (2004)
• Open source (soon)

Try it! http//flink.semanticweb.org
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(No Transcript)
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Technology highlights

• Social network mining from the Web and other
  legacy sources (emails, publications)
• Social networks based ontology extraction
• Collection of FOAF data from the SW
  (scuttering)
• Aggregation and identity reasoning (smushing)
• Custom inferencing using Sesame
• OWL use
• sameAs, inverse functional properties
• Web Service integration
• geographic lookup
• WML interface

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Semantic Web
Emails
Web
Publications
FOAF profiles
Web mining
IMAP or POP3
Google Scholar, Bibster
Sesame
Sesame
Sesame
Sesame
Sesame
RDF storage
Metadata enrichment (Identity reasoning,
geographic lookup)
JUNG
Network API
Network analysis
Web application
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Interoperability (1)

• Interoperability on the knowledge level
• syntax semantics context
• Syntax
• Easy (but a forgiving parser would be nice)
• Semantics
• Doable shared ontologies, ontology mapping (e.g.
  for foafinterests), unique object identification
  (e.g. for foafPerson),
• Context
• Challenge

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Interoperability (2) Context

• Provenance where the information comes from,
  when was it collected?
• Time-to-live how long is it going to stay valid?
• Trust and ratings is it considered trustworthy
  (by someone), is it important (for someone)?
• Security who can access it and how?

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Interoperability (3)Process

• How do we find each other?
• Registries vs. pointers
• How do we exchange?
• Connectivity
• Protocol (e.g. subscriptions vs. advertizements)
• What do we exchange?
• Files, access etc.
• Why would we exchange?
• The economics

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Flink and the FOAF-web

• Flink interoperates with the FOAF-web
• Producer and consumer of FOAF data
• But 762 other definitions of Person
  (www.swoogle.org), including swrcPerson
• FOAF-web is the kind of nightmare the SW promises
  to be
• Open, decentralized system
• Distributed data and services
• Issues of syntax and semantics
• Lack of authority, privacy etc.

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Flink and the FOAF-web (2)

• Majority of files are incorrect XML, RDF or FOAF
• Errors from the obvious to the sneaky
• e.g. ltfoafmbox_sha1sum /gt
• Ignore
• FOAF extensions
• What to do with them?
• Ignore on import, dont export
• FOAF interests?
• A loose end in FOAF (like dcCreator)
• Ignore (on import)
• Who is right?
• Let the user decide

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How to contact Dan Brickley?
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Summary

• Interoperability is a challenge
• Knowledge syntax semantics context
• Process
• Interoperability is about coming to an agreement
• Realize the trade-off between level of commitment
  vs. scale