The document discusses Linked Open Data and the Semantic Web. It explains that the Semantic Web aims to evolve the classic web by adding formal representations of data and knowledge that can be processed by machines. This will allow information on the web to be correlated and presented in a more intelligent way. Key points include using languages like RDF to represent data, creating ontologies to define vocabularies, and linking open data together to form a global knowledge graph that machines can process to provide smarter applications and services.
1. Linked Open Data ... and why you should care.
Christian Morbidoni <christian.morbidoni@gmail.com>
This work is licensed under a Creative Commons Attribution-NoDerivs 2.5 Italy
SeMedia
Università Politecnica delle Marche
Sunday, November 21, 2010
2. The Semantic Web is...
- A W3C initiative. The goal is to evolve the “classic”
Web.
- A big community of researchers and developers
- A set of languages for data and knowledge
representation
- Formal models
- A growing set of software tools supporting a
“smarter” Web
Sunday, November 21, 2010
3. WWW: basic components
- HTTP to trasfer data
- GET /index.html
- URLs to identify resources
- http://www.google.com/search?source=ig&hl=en&rlz=&=&q=semantic+web
- HTML to represent resources
- <html><head><title>…
- GCI, scripting, etc. to develop applications
Sunday, November 21, 2010
4. The “dumb” Web
- The Web is great as it contains a lot of information,
and sometimes it is easy to find what you look for
- But sometimes it behaves not so smartly
- We find out that Information that should be naturally
correlated... in the and are not
Sunday, November 21, 2010
8. The conference example
“Which one is hosting the ESWC?!??!”
“Why the aldemar web site does not even know that
the ESWC exists?!?!”
Sunday, November 21, 2010
9. Dumb web in action...
Finally after a lot of clicks I found a
couple of hotels for my budget
Sunday, November 21, 2010
10. Dumb web in azione ...
... but what is the closest to the conference
venue?
Sunday, November 21, 2010
11. Dumb web in azione ...
... but what is the closest to the conference
venue?
Sunday, November 21, 2010
12. Dumb web in azione ...
... but what is the closest to the conference
venue?
Sunday, November 21, 2010
13. Dumb web in azione ...
• After a lot of copy/paste into goole maps i find out
• .. but what a pain.After all it is a “mechanical” work and ...
• ... probably other people need to to the very same thing ...
• Why should I do it? Why not a machine?!?!?
Sunday, November 21, 2010
14. A bit of smartness finally ...
Sunday, November 21, 2010
15. A bit of smartness finally ...
Greek hotel owner
There are many systems like this.Why should I put
the same info again and againg.And modify them all
once I need to change them.
Sunday, November 21, 2010
16. So?
- We do not need more intelligent
applications ...
- We just need to let them find the right
data at the right time!
Sunday, November 21, 2010
17. Dumb Web revisited...
- We want addresses to be immediately recognized as such by a
machine ...
- ... than we want them to be sent automatically to gmaps (with one
click)
- ... but we also what this to happen without a priori agreement
Sunday, November 21, 2010
18. semantics is hidden, only humans (and not all of them)
can extract it from documents
Sunday, November 21, 2010
21. we explicitly say to machines
what we are talking about
... and we keep it simple...
... and we use simple, structured language
that they can understand.
Sunday, November 21, 2010
22. This is what the Semantic Web is all about.
The Resource Description Framework (RDF)
is the basic instrument
Sunday, November 21, 2010
24. Information can be useless without a
priori knowledge
Machines needs at least some vocabulary and basic
rules of the game
That is where ontologies come in
Sunday, November 21, 2010
25. Ontologies:
vocabularies for your domain
Source
Artistic Medium
Fresco
Mosaic
Manuscript Book
sub class of
sub class of
sub class of
sub class of
sub class of
Person
Artist
Caliph
sub class of
sub class of
Sunday, November 21, 2010
26. Ontologies:
vocabularies for your domain
Source
Artistic Medium
Fresco
Mosaic
Manuscript Book
sub class of
sub class of
sub class of
sub class of
sub class of
Person
Artist
Caliph
sub class of
sub class of
Divine Comedy
type
Dante Alighieri
type
San Petronio
Fresco
type Prophet Muhammad
type
Sunday, November 21, 2010
27. Ontologies:
vocabularies for your domain
Source
Artistic Medium
Fresco
Mosaic
Manuscript Book
sub class of
sub class of
sub class of
sub class of
sub class of
Person
Artist
Caliph
sub class of
sub class of
Divine Comedy
type
Dante Alighieri
type
San Petronio
Fresco
type Prophet Muhammad
type
has author
depicts
Sunday, November 21, 2010
28. Linking ?
The Web is great because it is so simple to jump
from a web page to the others
With the Semantic Web it should be easy to jump
from a database to an other:
Image separated clouds of data that are ready to
interoperate with each other ...
as if it was a unique world wide database
Sunday, November 21, 2010
29. Web of Documents vs.Web of Data
Presentation Layer
Data representation layer
Hyperlinks
?
RDF Data RDF Data RDF Data RDF Data
???
semantically defined relations ???
WebInfrastructure
Sunday, November 21, 2010
31. RDF and Web pages
RDF Data
http://example.com/home.htm http://example.com/home.rdf
Web Browser / Application
Sunday, November 21, 2010
32. RDF and Web pages
RDF Data
http://example.com/home.htm http://example.com/home.rdf
Web Browser / Application
RDF Data
Web Browser / Application
HTTP:
GET http://example.com/home/
CONTENT-TYPE application/rdf+xml
HTTP:
GET http://example.com/home/
CONTENT-TYPE text/html
Sunday, November 21, 2010
33. RDF and Web pages
RDF Data
http://example.com/home.htm http://example.com/home.rdf
Web Browser / Application
<html>
......
<rdf>
........
</rdf>
.......
</html>
RDF Data
RDF Data
Web Browser / Application
HTTP:
GET http://example.com/home/
CONTENT-TYPE application/rdf+xml
HTTP:
GET http://example.com/home/
CONTENT-TYPE text/html
Sunday, November 21, 2010
36. DONATELLO FLORENCEis from
BRUNELLESCHI
worked with
made
is a
Marble Statue
Museo Nazionale del
Bargello
is exposed in
DAVID
FROM wikipedia
FROM the museum web site
Sunday, November 21, 2010
37. The vision:
a collaborative knowledge graph
Note
Note
Note
Buraq
Prophet
Muhammad
Mecca
Buraq.jpg/2134
Buraq.txt/87874
is part of
is part of
mentions
mentions
is related to
Sunday, November 21, 2010
38. The vision:
a collaborative knowledge graph
Note
Note
Note
Note
Note
Buraq
Prophet
Muhammad
Mecca
Buraq.jpg/2134
Buraq.txt/87874
is part of
is part of
mentions
mentions
is related to
Sunday, November 21, 2010
39. The vision:
a collaborative knowledge graph
Note
Note
Note
Note
Note
Buraq
Prophet
Muhammad
Mecca
Buraq.jpg/2134
Buraq.txt/87874
is part of
is part of
mentions
mentions
is related to
A Book
comments on
An artist
reproduced
Sunday, November 21, 2010
40. The vision:
a collaborative knowledge graph
Note
Note
Note
Note
Note Note
Note
Note
Buraq
Prophet
Muhammad
Mecca
Buraq.jpg/2134
Buraq.txt/87874
is part of
is part of
mentions
mentions
is related to
A Book
comments on
An artist
reproduced
Sunday, November 21, 2010
41. The vision:
a collaborative knowledge graph
Note
Note
Note
Note
Note Note
Note
Note
Buraq
Prophet
Muhammad
Mecca
Buraq.jpg/2134
Buraq.txt/87874
is part of
is part of
mentions
mentions
is related to
A Book
comments on
An artist
reproduced
An other Book
is a revision of
is located in
A scholar
wrote
Sunday, November 21, 2010
42. The vision:
a collaborative knowledge graph
Note
Note
Note
Note
Note Note
Note
Note
Buraq
Prophet
Muhammad
Mecca
Buraq.jpg/2134
Buraq.txt/87874
is part of
is part of
mentions
mentions
is related to
A Book
comments on
An artist
reproduced
An other Book
is a revision of
is located in
A scholar
wrote
Editorial Policy (peer review?)
Publish on the Web
Sunday, November 21, 2010
43. An important consideration
The Semantic Web is not a magic thing
It doesn’t necessarily mean artificial intelligence
It aims at better structuring knowledge so that:
Independently produced knowledge can be more
easily merged
Applications can be smarter in collecting,
managing and presenting knowledge
Sunday, November 21, 2010
46. http://muruca.org
- open source tools for accessing the linked data now
- specifically targeted to small-medium communities
Sunday, November 21, 2010