Introduction to the Semantic Web

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Introduction to the Semantic Web

Asunción Gómez-Pérez

{asun}@fi.upm.es

http://www.oeg-upm.net

Omtological Engineering Group Laboratorio de Inteligencia Artificial

Facultad de Informática Universidad Politécnica de Madrid

Campus de Montegancedo sn, 28660 Boadilla del Monte, Madrid, Spain

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URI, HTML, HTTP

WWW

Static

Users

Pages

The problem: Information overload on the WEb

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The current Web is based on HTML

رﻮﻄﺘﻟاﻢﻠﻌىﻓﺔﺳﺪﻨﻬﻟا :ﻢﺳﻻا زﺮﺒـﺰﻣﻮﻏنﻮﻴﺴﻨﺳﺁ : نﻮﻔّﻟﺆﻤﻟا $74.95 :ﺮﻌّﺴﻟا ﺞﺘﻨﻤﻟا : بﺎﺘﻜﻟا رﻮﻄﺘﻟاﻢﻠﻌىﻓﺔﺳﺪﻨﻬﻟا: ﻢﺳﻻا زﺮﺒـﺰﻣﻮﻏنﻮﻴﺴﻨﺳﺁ: نﻮﻔّﻟﺆﻤﻟا $74.95 : ﺮﻌّﺴﻟا بﺎﺘﻜﻟا: ﺞﺘﻨﻤﻟا Árabe

Title: Ontological Engineering Authors: Asunción Gómez-Pérez... Price: $74.95

Product: Book

Title:Ontological Engineering Authors:Asunción Gómez-Pérez... Price:$74.95

Product:Book

Inglés

Skjøte: Ontological Ingeniørarbeid Forfatter: Overtakelse Gómez-Pérez... Pris: 74.95€

Produkt: Bok

Skjøte:Ontological Ingeniørarbeid Forfatter:Overtakelse Gómez-Pérez... Pris:74.95€

Produkt:Bok

No

ruego

.- HTML is useful for browsing the information .- Content is language-dependent

.- High cost for keeping the information up-to-date

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XML allows the creation of metada with

“meaning”

¿What do the tags

mean

for the machine?

<Title>Ontological Engineering</Title> <Author>Asunción Gómez-Pérez...</Author> <Price>$74.95</Price>

Title:Ontological Engineering Authors:Asunción Gómez-Pérez... Price:$74.95 Product:Book Inglés <ﻢﺳﻻا> رﻮﻄﺘﻟاﻢﻠﻌىﻓﺔﺳﺪﻨﻬﻟا</ﻢﺳﻻا> < نﻮﻔّﻟﺆﻤﻟا> زﺮﺒـﺰﻣﻮﻏنﻮﻴﺴﻨﺳﺁ</ نﻮﻔّﻟﺆﻤﻟا> <ﺮﻌّﺴﻟا>$74.95</ﺮﻌّﺴﻟا> <بﺎﺘﻜﻟا> ﺞﺘﻨﻤﻟا</بﺎﺘﻜﻟا> رﻮﻄﺘﻟاﻢﻠﻌىﻓﺔﺳﺪﻨﻬﻟا: ﻢﺳﻻا زﺮﺒـﺰﻣﻮﻏنﻮﻴﺴﻨﺳﺁ: نﻮﻔّﻟﺆﻤﻟا $74.95 : ﺮﻌّﺴﻟا بﺎﺘﻜﻟا: ﺞﺘﻨﻤﻟا Árabe

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The problem of choosing information

.- Find the information

.- Extract relevant information .- Interpretation by human users .- Sinthesis

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The problem of content agregation:

From Madrid to Tokyo

.-Content in different languages (Spanish, English, Japanesse,...) .- Find out relevant information from heterogeneous sources

.- Extract

.- Interpretation .- Agregation

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What

was the Web intended to be?

“... a goal of the Web was that, if the interaction between

person and hypertext could be so intuitive that the

machine-readable

information space gave an accurate

representation of the state of people's thoughts,

interactions, and work patterns, then

machine analysis

could become a very powerful management tool, seeing

patterns in our work and facilitating our working together

through the typical problems which beset the management

of large organizations.”

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“The Semantic Web is an

extension

of the current Web in which

information is given

well-defined meaning

, better enabling computers

and people to work in

cooperation

. It is based on the idea of having data

on the Web defined and linked such that it can be used for more

effective

discovery, automation, integration, and reuse across various

applications

.”

Hendler, J., Berners-Lee, T., and Miller, E.

Integrating Applications on the Semantic Web, 2002,

http://www.w3.org/2002/07/swint.html

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IBXX is a flight. Its

departure place is

Madrid and its arrival

place is Tokyo.

Madrid is an european

city. Tokyo is an

asian city.

Herzt is a

rental car

company with

luxury cars in

tokyo.

The new

national theater

is a theater

located in

Tokyo.It has

peformances

every Saturday.

Why not make the computers do the work?

Metadata

Integration

Knowledge

Inference

Xxx is a

hotel placed

in Tokyo

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Definition of Ontology

“An ontology is a formal, explicit specification of a

shared conceptualization

”

Machine-readable

Abstract model and

simplified view of some

phenomenon in the world

that we want to represent

Concepts, properties

relations, functions,

constraints, axioms,

are explicitly defined

Consensual

Knowledge

Frames and FoL

Subclass of Living Being Animals Plants Subclass of Subclass of Subclass of Mammals _Birds Ontologías XML RDF RDFS OWL RDF(S)

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Travel

rdfs:Literal rdfs:Class Company-name singleFare units:currencyQuantity rdfs:range rdfs:range rdfs:domain rdfs:domai n rdf:Type departureDate rdfs:domai n xsd:Date rdfs:range arrivalDate rdfs:range rdfs:domain rdf:Property rdf:Type rdf:Type rdf:Type rdf:Type RDF RDFS

Ontology in RDF(S)

rdfs:Class rdf:ID="Travel">

<rdfs:comment>A journey from place to place</rdfs:comment>

</rdfs:Class>

<rdf:Property rdf:ID="arrivalDate"> <rdfs:domain rdf:resource="#Travel"/> <rdfs:range rdf:resource="&xsd;date"/>

</rdf:Property>

<rdf:Property rdf:ID="departureDate"> <rdfs:domain rdf:resource="#Travel"/> <rdfs:range rdf:resource="&xsd;date"/>

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IB-4321

Iberia Company-name singleFare 500 euros departureDate 10/11/2005 arrivalDate

<RS-travel:Travel rdf:ID=“IB-4321">

<RS-travel:Company-name>Iberia</RS-travel:Company-name> <RS-travel:singleFare>500 Euros</singleFare>

<RS-travel:departureDate rdf:datatype="&xsd;date">2005-11-10 </RS-travel:departureDate> <RS-travel:arrivalDate rdf:datatype="&xsd;date"> 2005-11-10 </RS-travel:arrivalDate> <RS-travel:arrivalPlace rdf:resource="#Paris"/>

</RS-travel:Travel>

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Travel

rdfs:Literal rdfs:Class Company-name singleFare units:currencyQuantity rdfs:range rdfs:range rdfs:domain rdfs:domain rdf:Type departureDate rdfs:domain time:Date rdfs:range arrivalDate rdfs:range rdfs:domain rdf:Property rdf:Type

rdf:Type rdf:Type rdf:Type

RDF RDFS

IB-4321

“Iberia” 500 euros 10/11/2005 singleFare _{departureDate} arrivalDate Company-name rdf:Type rdf:Type rdf:Type rdf:Type

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rdfs:Class rdf:ID="Travel">

<rdfs:comment>A journey from place to place</rdfs:comment>

</rdfs:Class>

<rdf:Property rdf:ID="arrivalDate"> <rdfs:domain rdf:resource="#Travel"/> <rdfs:range rdf:resource="&xsd;date"/> </rdf:Property>

<rdf:Property rdf:ID="departureDate"> <rdfs:domain rdf:resource="#Travel"/> <rdfs:range rdf:resource="&xsd;date"/> </rdf:Property>

...

<RS-travel:Travelrdf:ID=“IB-4321">

<RS-travel:Company-name>Iberia</RS-travel:Company-name> <RS-travel:singleFare>500 Euros</singleFare>

<RS-travel:departureDate rdf:datatype="&xsd;date">2005-11-10</RS-travel:departureDate> <RS-travel:arrivalDaterdf:datatype="&xsd;date"> 2005-11-10 </RS-travel:arrivalDate> <RS-travel:arrivalPlace rdf:resource="#Paris"/>

</RS-travel:Travel>

...

Travel.rdfs

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Language independent •Protégé-Frames •WebODE •OntoEdit •KAON1 •IODT (IBM) Language Dependent

•

NeOn Toolkit (new) !!

•Protégé-OWL y Protégé 4 •SWOOP

•Ontolingua •OntoSaurus •WebOnto

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Static URI, HTML, HTTPWWW

Web services

RDF, RDFS, OWL Semantic Web UDDI, WSDL, SOAP Web Services Dynamic Semantic Service registries

Service access interface Communication protocol Control flow description

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Semantic Web Services

Static Dynamic Semantic Servicios Web Semánticos DAML-S, OWL-S WSMO

Web services are described using Ontologies and are expressed in Semantic web service language

RDF, RDFS, OWL Semantic Web UDDI, WSDL, SOAP Web Services URI, HTML, HTTP WWW

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Real world Users _Companies

Agent Agent Agente Agent

Intelligent

agents IntelligentAgents

Semantic Web Services _Metadata

Semantic Web Scenario

P2P system

RDF(S) DAML+OIL OWL Repositories /tools

Emails Documents

Static Web pages

Online DB (Unknown schema) applications _{Web services}

Restricted Webs

Dynamic Web pages

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Ontological Engineering for the Semantic Web

Build Ontologies

Tools

Methodologies and

methods

Reasoners

Applications

Lenguages

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Introduction to the Semantic Web

Asunción Gómez-Pérez

{asun}@fi.upm.es

http://www.oeg-upm.net

Omtological Engineering Group Laboratorio de Inteligencia Artificial

Facultad de Informática Universidad Politécnica de Madrid

Campus de Montegancedo sn, 28660 Boadilla del Monte, Madrid, Spain