sesam4 tech.primer.csaba.veres.rdf.owl.video
DESCRIPTION
This slideshare belongs to a technology primer on OWL/RDF, produced by Csaba Veres (Bergen University, Norway) for the SESAM4 project.TRANSCRIPT
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
NFR Verdikt Project no 2342453 Semantic Technology
A guide to semantics in the Linked Open Data cloud:RDF and OWL
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
What are RDF and OWL?
RDF: Resource Description Framework Resource - Any piece of data you can put on the Web Description - Relationships between the Data A Data Model
OWL: Web Ontology Language More Complex descriptions of Data
Reasoning and Search
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
Why a Data Model?
• Data models are not new
Name Address Telephone
John Smith
Henry Frod
2 Nowhere place 111 222 333
15 Upmarket drive 123 456 789
NameAddressTelephone
Person
First NameSecond NameResidenceContact
Person
First Name Second Name Residence Contact
John Smith
Henry Frod
2 Nowhere place 111 222 333
15 Upmarket drive 123 456 789
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
Why a Data Model for the Web?
Name Address Telephone
John Smith
Henry Frod
2 Nowhere place111 222 333
15 Upmarket drive123 456 789
First Name Second Name Residence Contact
Jane Smith
Henrietta Frod
2 Nowhere place 111 222 333
15 Upmarket [email protected]
+
= ???Name Residence Telephone Email
Jane Smith
Henrietta Frod
John Smith
Henri Frod
2 Nowhere place 111 222 333
15 Upmarket drive [email protected]
2 Nowhere place 111 222 333
15 Upmarket drive 123 456 789
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
Identify Resources in Web Space
How many houses does John Smith have? John Smith at 2 Nowhere place John Smith at 47 Hope street Does he have two houses, or two different people?
URI General form of URL Every entity gets one
http://www.example.org/person#js1 http://www.example.org/person#js2
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
What do we know about John Smith?
We know http://www.example.org/person#js1
has name “John Smith” has address “2 Nowhere place” has phone number “111 222 333”
http://www.example.org/person#js2 has name “John Smith” has address “47 Hope street” has phone number “333 222 111”
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
Some RDF
@ prefix person <http://www.example.org/person#> .@ prefix property <http://www.example.org/property#> .person:js1 property:hasName “John Smith” ;
property:hasAddress “2 Nowhere place” ;property:hasPhone “111 222 333” .
person:js2 property:hasName “John Smith” ;property:hasAddress “47 Hope street” ;property:hasPhone “333 222 111” .
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
General RDF
Basic data model is a “triple”
Subject Objectpredicate
person:JS1 “John Smith”property:hasName
person:JS2property:hasFriend
“John Smith”property:hasName
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
Why is RDF good?
Globally unique identifier Extensible, distributed data model: just add triples
Guaranteed results! End of data silos! Integrate company data Expose selected company data
Name College Graduation Employer Salary
John Smith
...
Stanford 1987 Apple Inc. US$160,000
... ... ... ...
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
Why RDF + OWL is even better Suppose you have a huge graph with tons of facts about
tons of people And you want to find potential customers “Well educated people working in a tech. company who is likely
to have disposable income, and willing to part with it” OWL allows you to build complex domain models and
define concepts like “potential customer” well educated = B.Sc. or Ph.D. tech company = company hasProduct (computer or mobile
phone or software) disposable income = hasSalary > 100,000 & (owns iPhone) or
(hasAccount FaceBook)
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
Summary RDF is a simple, extensible, distributed data model
Data integration Expose data Tools for “lifting” legacy data
OWL Domain models: Ontologies Simplifies finding the data you need
RDF + OWL All the data, and just the data you want
Technology PrimerSESAM4 2011
SESAM4 Consortium 2009 – 2011Published under Creative Commons license
www.sesam4.net