rdf (resource description framework). 2 table of contents introduction basic rdf –basic rdf...
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RDF(Resource Description Framework)
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Table of Contents
Introduction Basic RDF
– Basic RDF Model– Basic Syntax
Containers Statements about Statements examples
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Introduction
Conception– Foundation for processing metadata.– Provides interoperability between Applications
that exchange machine-understandable information on the Web.
– A Model for representing RDF metadata.– A Syntax for encoding and Transporting this
metadata in a manner. ( using of XML Syntax)– Have a Class System much like OOP.
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Introduction
using– Resource discovery.– Digital library.– Intelligent software agents.– Privacy Policies.– Etc..
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Basic RDF Model No1
A Model for representing named properties and property values
A Syntax-neutral way of representing RDF expressions
Consists of Object types– Resource– Properties– Statements
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Basic RDF Model No2
Resources– ALL things being described by RDF expressions are cal
led resources
Properties– A Property is a specific aspect, characteristic, attribute o
r relation used to describe a resource
Statements– A specific resource together with a named property plus
the value of that property for that resource is an RDF statment
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Basic RDF Model No3
Subject(Resource) http://www.w3c.org/Home/Lassila
Predicate(Propery) Creator
Object(literal) “Ora Lassila”
sentence
Ora Lassila the creator of the resource http://www.w3c.org/Home/Lassila
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Basic RDF Model (Simple node and arc diagram)
http://www.w3c.org/Home/Lassila Ora LassilaCreator
The graph consists of two nodes connected by a single arc. One node (represented as an oval) contains the URI text http://www.w3.org/Home/Lassila and the other (represented as a rectangle) contains the text "Ora Lassila". The arc connecting these nodes bears the label Creator.
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Basic RDF Model (Property with structured Value)
http://www.w3c.org/Home/Lassila
Creator
Ora Lassila
Name Email
sentence
The individual whose name is Ora Lassila, email <[email protected]>, is the creator of http://www.w3.org/Home/Lassila.
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Basic RDF Model (Structured value with identifier)
http://www.w3c.org/Home/Lassila
Creator
Ora Lassila
http://www.w3.org/staffId/85740
Name Email
sentence
The individual referred to by employee id 85740 is named Ora Lassila and has the email address [email protected]. The resource http://www.w3.org/Home/Lassila was created by this individual.
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Basic RDF Syntax No1
RDF data model provides an abstract, conceptual framework for defining and using metadata
Concrete syntax is also needed for the purpose of creating and exchanging this metadata
Syntax descriptions in this document use the Extended Backus-Naur Form notation of [XML] to describe the essential RDF Syntax elements
Define two XML Syntax for encoding an RDF data model instance
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Basic RDF Syntax No2
Serialization Syntax Express– The RDF XML syntax has been designed to accomoda
te this easily by grouping multiple statements for the same resource into a Description element
Abbreviated Syntax Express– Describle to use a more compact XML form
– Three forms of abbreviation are defined for the basic serialization syntax
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Serialization Syntax Express
sentenceOra Lassila is the creator of the resourcehttp://www.w3c.org/Home/Lassila
<?XML version=“1.0 ?><rdf:RDF xmlns:rdf = “http://www.w3c.org/1999/02/22-rdf-syntax-ns#”xmlns:s = “http://description.org/schema/ “ >
<rdf:Description about=“http://www.w3c.org/Home/Lassila><s:Creator>Ora Lassila </s:Creator>
</rdf:Description></rdf:RDF>
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Abbreviated Syntax Express
The first is usable for properties that are not repeated within a Description and where the values of those properties are literals
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Abbreviated Syntax Express
<rdf:RDF> <rdf:Description about="http://www.w3.org">
<s:Publisher>World Wide Web Consortium</s:Publisher> <s:Title>W3C Home Page</s:Title>
<s:Date>1998-10-03T02:27</s:Date> </rdf:Description>
</rdf:RDF>
<rdf:RDF> <rdf:Description
about="http://www.w3.org" s:Publisher="World Wide Web Consortium" s:Title="W3C Home Page" s:Date="1998-10-03T02:27"/>
</rdf:RDF>
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Abbreviated Syntax Express
The second RDF abbreviation form works on nested Description elements
SentenceThe individual referred to by employee id 85740 is named Ora Lassila an
d has the email address [email protected]. The resource http://www.w3.
org/Home/Lassila was created by this individual.
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Abbreviated Syntax Express
<rdf:RDF> <rdf:Description about="http://www.w3.org/Home/Lassila">
<s:Creator rdf:resource="http://www.w3.org/staffId/85740"/> </rdf:Description>
<rdf:Description about="http://www.w3.org/staffId/85740"> <v:Name>Ora Lassila</v:Name>
<v:Email>[email protected]</v:Email> </rdf:Description>
</rdf:RDF>
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Abbreviated Syntax Express
<rdf:RDF> <rdf:Description about="http://www.w3.org/Home/Lassila"> <s:Creator>
<rdf:Description about="http://www.w3.org/staffId/85740"> <v:Name>Ora Lassila</v:Name>
<v:Email>[email protected]</v:Email> </rdf:Description>
</s:Creator> </rdf:Description> </rdf:RDF>
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Abbreviated Syntax Express
<rdf:RDF> <rdf:Description about="http://www.w3.org/Home/Lassila">
<s:Creator rdf:resource="http://www.w3.org/staffId/85740" v:Name="Ora Lassila" v:Email="[email protected]" />
</rdf:Description> </rdf:RDF>
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Abbreviated Syntax Express
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:s="http://description.org/schema/"> <rdf:Description about="http://www.w3.org/Home/Lassila"> <s:Creator>
<rdf:Description about="http://www.w3.org/staffId/85740"> <rdf:type resource="http://description.org/schema/Person"/>
<v:Name>Ora Lassila</v:Name> <v:Email>[email protected]</v:Email> </rdf:Description>
</s:Creator> </rdf:Description> </rdf:RDF>
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Abbreviated Syntax Express
<rdf:RDF> <rdf:Description about="http://www.w3.org/Home/Lassila"> <s:Creator> <s:Person about="http://www.w3.org/staffId/85740">
<v:Name>Ora Lassila</v:Name> <v:Email>[email protected]</v:Email>
</s:Person> </s:Creator> </rdf:Description> </rdf:RDF>
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Reference
W3C RDF– http://www.w3c.org/rdf– Resource Description Framework
(RDF) Model and Syntax Specification