Talk at SEMANTiCS 2017 www.semantics.cc

1. Linking thesauri

2. About me
Matthias Priem
VIAA
Manager Archiving

3. Over VIAA

4. Not (only) a
Broadcast
Archive

5. CULTURAL
HERITAGE
We don’t
own
collections
Currently:
+/- 100 orgs
CITY
ARCHIVES BROADCAST
SERVICE
PROVIDER

6. DIGITISATION

7. VIAA FACTS & FIGURES
● Total carriers identified: 650.000
● Total carriers digitised today: 227.000
● About 30% done (but most projects are started)

8. DIGITAL
ARCHIVE
SYSTEM

9. VIAA FACTS & FIGURES
● Archive today:
80.000+ hours (2 PB)
● Growing 15+ TB/day
(that’s almost 0,5 PB / month)

10. VIAA FACTS & FIGURES
● Archive today: +80.000
hours / 2 PB
● Growing 15TB/day
(that’s 0.5 PB / month)

11. EDUCATION

12. VIAA FACTS & FIGURES in 50% of all
schools
(in < 1 year)

13. VIAA FACTS & FIGURES in 50% of all
schools
Fiat/IFTA
nominee

14. VIAA and thesauri
● VIAA archives collections of
more than 100 organisations
● Multiple sectors with large
differences
● Feasibility study in 2014
“Can we build one ‘unified’
thesaurus and if so: how?”

15. Feasibility study: main outcomes
● One generic thesaurus won’t work
○ Huge discussions on content
○ Very niche thesauri vs. more generalist
● But
○ What about SKOS
○ And what about linking thesauri

16. What about SKOS?
● Standardized way for knowledge organisation
● W3C, semantic web
● Main contents
○ Concepts with descriptions
○ Hierarchy
○ Alternative names
○ Multilingual
○ ...and links: exactMatch, ...

17. What about linking thesauri?
voc1
voc2
• Allows people to work on their own
thesaurus
• Benefit from each others work
• Allow unified search

18. But linking
manually…?

19. About Sound & Vision
Audiovisual archief van
Nederland
> 800.000 uur materiaal
(tv, radio, muziek, docu,
film, commercials, etc.)
Archive + Access
GTAA!!
“Archive as Lab”
● Smart
● Connected
● Open

20. About Taalunie
● Support of Dutch
around the globe
● Also active in the
field of digital
heritage

21. Linked Thesaurus for Uniform Dissemination
● Source selection
● SKOSification
● Alignment (linking of the sources)
● Demonstrator

22. With a little help from our friends

23. Source thesauri
GTAA (SKOS)
VRT Thesaurus
(not SKOS.. yet)

24. VRT Thesaurus
100.000+ terms
Structured
Every term has an ID
Not standardized
Not published
Managed as part of AVID
Bit of a ‘black box’

25. VRT Thesaurus
Relations in the thesaurus

26. VRT Thesaurus
Hierarchical relations, to SKOS
(‘broader’ en ‘narrower’)
Also: related terms

27. Amsterdam in SKOS (turtle)

28. VRT Thesaurus: scopeNotes

29. Synonyms

30. VRT Thesaurus after SKOSification
102.172 terms (concepts)
97.744 terms are linked hierarchically
4.429 topConcepts
212 scopeNotes
6828 relations between terms

31. GTAA
184.484 termen
19.695 terms are linked hierarchically
9 conceptSchemes (persons, locations, …)
90.708 scopeNotes
33.542 relaties
=> published as linked open data J

32. Linking thesauri together
http://CultuurLINK.beeldengeluid.nl

33. Linking thesauri
Start working with two thesauri
Isolate a part of it (e.g. geographical names)
Compare the resulting terms
- String matching
- or more complex operations
Re-iterate on non-matching terms

34. Linking subjects

35. Linking People (zoom)
FILTERS
COMPARISON

36. Linking People (zoom)
VERIFY

37. Linking People (zoom)
REPEAT

38. Linking People

39. Result of the linking process
Term # of Links
Subjects (things) 4.167
Names (bands, companies,...) 2.197
Locations 4.011
Persons 11.265
Total 21.640

40. Learnings
● Linking is not (very) technical
● Linking requires knowledge of the sources
● Linking requires human input
● Richer thesaurus: more chance of finding
links

41. http://link.spinque.com/VIAA-1.0/
Demonstrator

42. Demonstrator - Sources
● VIAA
○ Part of the VRT collection.
○ +/- 35.000 items (of 1 mio records)
○ Annotations and links to the thesaurus
● Sound & Vision
○ ‘Openbeelden’
○ Again: a small part of the archive
○ The annotation of those items.

43. SLIDER
determines weight of the collection
SEARCH

44. Keyword “migration”
All matching keywords of all search results (grouped & with indicator)
Search results
with highlighted
- matches in
descriptions
- matches in
thesaurus terms
collection indicator

45. Changed the weight towards the North
… more results
from across the
border

46. Clicked video is now the search criterium
Terms with associated with all related video’s
Related video’s

47. User searches for related VRT content based
on the B&G video.

48. Conclusions
● Up until now: we gained a lot of insight in working with
thesauri
○ SKOS
○ Linking thesauri
○ Linked and open data
○ Got a good view on what thesaurus landscape
looks like
● Linking makes thesauri richer, allows for collaborative
work

49. Many more steps ahead
● Select thesauri to start working from
○ Link them where appropriate
○ Reuse existing sources where possible (VIAF, GeoNames, …)
● Manage
○ Good management tool and workflow for thesauri
● Use (integration, integration, integration)
○ Use (public) LOD sources in our collection mgmt system (!)
○ Use them as reference source for term extraction
○ Re-use the terms in user-facing systems

50. Thanks!