Resource and Metadata Managementwith a Linked Data perspective

Meetup: Linked Data in SwedenApril 17, 2012

Hannes Ebnerhebner@kth.sehannes@metasolutions.se

Multiple projects with similar goals

• Organic.Edunet as example because of its characteristics- Heterogeneous metadata- Multiple stakeholders and standards- Ontology- Big user base- Used in production environments- Not typically academic (content-centric)

EntryStore – conceptual overview

• Named graphs• REST API• ACL• Harvesting• Querying• On-the-fly MD conversions• SPARQL• Literal indexing

Open Source

Interoperability

FAO

Bio@gro

Intute

OrganicEPrints

EntryStore

LOM/XML

CustomXML

YouTubeDC/RDF

DC/RDF

Custom

OAI-PMHSQI

HTTP SPARQL

RDF coreSolr

Lessons learned - ontology

• Ontology- Good for domain experts- Pain for “annotators”- Nobody used ontology tree

• Flat list with type-ahead is popular• Difficult to grasp hierarchy

Lessons learned - licensing

• Ensure licensing is clear- Creative Commons- Open Data Commons- Custom licenses- Organic.Edunet: CC0

• Data != Metadata- Often confused when it comes to licensing

Lessons learned - interoperability

• W3C standards everywhere- Exception: some formats, e.g. IEEE LOM

• Triplification has to be done by experts

• Remix of various vocabularies

• Search engines find resources directly

Lessons learned – practical problems

• Complexity- Try to find a student...- Big technology stack

• Need for authoritative and quality-controlled (meta)data

• Legacy data has to be converted and mapped

• Scalability

WIN!

No user ever noticed the technology behind

“Rule number 1 in building web software: never show the URI. If the URI does not have a label, go and beat

somebody up.”

Tim Berners-Lee at LDOWApril 16, 2012

FAIL?

OK, there was the ontology...

“The one big ontology approach didn't work”

Tim Berners-Lee at LDOWApril 16, 2012

Current work / experiments

• Data-driven Sustainability- footprinted.org, in collaboration with Sourcemap.com- Data bridges (EIT ICT Labs)- Miljöbarometern (visualizations, Google Refine)- Green Hackathon

• Large scale triplification and interlinking of educational metadata- ARIADNE- Open Discovery Space

• Contextualization of cultural heritage metadata- Europeana (Hack4Europe!)