The document discusses the Semantic Web and linked data. It describes standards like RDF, RDFS, and OWL that add structure and meaning to data on the web. Triples are used to represent information that can then be queried or linked to other data to form a global graph. The principles of linked data encourage using URIs, HTTP, and content negotiation to publish and interconnect structured data on the web.

1. when the link makes sense
semantic web: linking data and schemas on the web
fabien, gandon, @fabien_gandon, http://fabien.info

2. le web originel
liens typés…

3. SEMANTIC WEB STANDARD STACK
W3C®

4. A WEB OF
LINKED DATA
W3C®

5. RDF is a triple model i.e. every
piece of knowledge is broken down into
( subject , predicate , object )

6. doc.html has for author Fabien
and has for theme Music

7. doc.html has for author Fabien
doc.html has for theme Music

8. RDFtriples can be seen as arcs
of a graph (vertex,edge,vertex)
(the RDF data model can be seen as a directed labelled multigraph)

9. Fabien
author
doc.html
theme
Music

10. identify what
exists on the
web
http://my-site.fr
identify,
on the web,
what exists
http://animals.org/this-zebra

11. http://ns.inria.fr/fabien.gandon#me
http://inria.fr/schema#author
http://inria.fr/rr/doc.html
http://inria.fr/schema#theme
"Music"

12. http://ns.inria.fr/fabien.gandon#me
http://inria.fr/schema#author
http://inria.fr/rr/doc.html
http://inria.fr/rr/doc.html
http://inria.fr/schema#theme
Music

13. open and link data in a
global giant graph

14. <
RDF /> has an XML syntax
RDF has other syntaxes
(Turtle, JSON-LD, Triple)

15. ratatouille.fr

16. datatouille.fr

17. HTTP URI
GET
303
GET
HTML,RDF,…
linked data principles
 Use RDF as data format
 Use HTTP URIs as names for things so that
people can look up those names
 When someone looks up a URI, provide useful information
(RDF, HTML, etc.) using content negotiation
 Include links to other URIs so that related things can be discovered

18. May 2007
April 2008
September 2008
Linking Open Data
March 2009
400
300
200
100
0
10/10/2006 28/04/2007 14/11/2007 01/06/2008 18/12/2008 06/07/2009 22/01/2010 10/08/2010 26/02/2011 14/09/2011 01/04/2012
September 2011
Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. http://lod-cloud.net/
September 2010

19. thematic content
Number of
datasets
Number of
Triples
%
Out links
%
Media
25
1 841 852 061
5,82 %
50 440 705
10,01 %
Geography
31
6145 532 484
19,43 %
35 812 328
7,11 %
Government
49
13 315 009 400
42,09 %
19 343 519
3,84 %
Publications
87
2 950 720 693
9,33 %
139 925 218
27,76 %
Inter-domain
41
4 184 635 715
13,23 %
63 183 065
12,54 %
Life Sciences
41
3 036 336 004
9,60 %
191 844 090
38,06 %
Users’ content
20
134 127 413
0,42 %
3 449 143
0,68 %
295
31 634 213 770
Domains
503 998 829
0%
9%
6%
42%
10%
Government
Geography
Inter-domain
13%
Life Sciences
Publications
20%
Media
Users' content

22. query with SPARQL
SPARQL Protocol and RDF
Query Language

23. e.g. DBpedia

25. HTTP
SPARQL

26. Linked Data Platform
REST like access to LD resources & containers
HTTP for accessing, updating, creating and deleting
resources from linked data servers.
PUT http://data.inria.fr/people/fab
Host: data.inria.fr
Content-Type: text/turtle
HTTP/1.1
<fab> a foaf:Person ;
rdfs:label "Fabien" ;
foaf:mbox <fabien.gandon@inria.fr> .

27. don’t read
the sign

28. you loose!

29. we identify and interpret information,
machines don’t.

30. 180°C+
=?

publish the data schemas
+
=


31. semantic web
mentioned by Tim BL
in 1994 at WWW
[Tim Berners-Lee 1994, http://www.w3.org/Talks/WWW94Tim/]

32. PUBLISHED
SEMANTICS
OF SCHEMAS
W3C®

33. RDFS to declare classes of
resources, properties, and
organize their hierarchy
Document
creator
author
Report
Document
Person

34. OWL in one…

algebraic properties
!
union
disjunction
intersection
complement
restriction
1..1
disjoint properties
1..1
! qualified cardinality
individual prop. neg


chained prop.
cardinality
 equivalence
enumeration
[>18] value restrict.
disjoint union

keys
…

36. Discovery Hub (Inria, Alcatel Bell Lucent)

37. open your data
to those who could use them

38. watchdogs #wearedata

42. many data
buried and dormant in web pages

43. schema
mapping
R2RML
a standard transformation of a
relationnal database in RDF

44. publication
Datalift process
demo
• one click setup
• raw data import
• RDF transformation
• Web publication
• online querying

46. RDFa means
RDF in HTML attributs
<div xmlns:dc="http://purl.org/dc/elements/1.1/">
<h2 property="dc:title">The trouble with Bob</h2>
<h3 property="dc:creator">Alice</h3>
...
</div>

47. schema.org =
+
+
+
schemas to improve index, search and display e.g:
•
•
•
•
•
•
•
•
Creative works, Book, Movie, MusicRecording, Recipe, TVSeries ...
Embedded non-text objects, AudioObject, ImageObject, VideoObject
Event
Organization
Person
Place, LocalBusiness, Restaurant ...
Product, Offer, AggregateOffer
Review, AggregateRating

49. presentation
RDFa, microdata,…
LDP, HTTP, JSON-LD, …
logic
data
R2RML, SPARQL, RDF, …
a (too) fast three-tier summary

50. http://www.w3.org/2001/sw/wiki/Tools

54. towards rich webmarks

55. QAKIS: natural language queries

56. doggy-bag

57. web 1, 2

58. web 1, 2, 3
person
price
homepage?
convert?
more info?

59. he who controls metadata, controls the web
and through the world-wide web many things in our world.
fabien, gandon, @fabien_gandon, http://fabien.info