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CSE 428 Semantic Web Topics RDF. Jeff Heflin Lehigh University. Turtle vs. RDF/XML. Turtle: - PowerPoint PPT Presentation
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CSE 428Semantic Web TopicsRDF
Jeff Heflin
Lehigh University
Turtle vs. RDF/XML
Turtle:@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .@prefix foaf: <http://xmlns.com/foaf/0.1/> .<http://www.yahoo.com/~jdoe#jane> foaf:name "Jane Doe" ; foaf:knows http://www.yahoo.com/~jsmith#john .
RDF/XML:<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:foaf="http://xmlns.com/foaf/0.1/"> <rdf:Description rdf:about="http://www.yahoo.com/~jdoe#jane"> <foaf:knows rdf:resource="http://www.yahoo.com/~jsmith#john" />
<foaf:name>Jane Doe</foaf:name> </rdf:Description>
</rdf:RDF>
Default Namespaces
<rdf:RDF xmlns="http://xmlns.com/foaf/0.1/"xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdf:Description rdf:about="http://www.yahoo.com/~jdoe#jane"> <knows rdf:resource="http://www.yahoo.com/~jsmith#john" /> <name>Jane Doe</name> </rdf:Description>
</rdf:RDF>
Using XML Entities
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">] >
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"xmlns:foaf="http://xmlns.com/foaf/0.1/" >
<rdf:Description rdf:about="http://www.aol.com/~jdoe"> <foaf:age rdf:datatype="&xsd;integer">30</foaf:age>
</rdf:Description> </rdf:RDF>
Resolves to:http://www.w3.org/2001/XMLSchema#integer
Nesting Descriptions
<rdf:RDF xmlns="http://xmlns.com/foaf/0.1/"xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdf:Description rdf:about="http://www.aol.com/~jdoe"> <foaf:name>Jane Doe</foaf:name><foaf:knows><rdf:Description rdf:about="http://www.aol.com/~jsmith"> <foaf:name>John Smith</foaf:name>
</rdf:Description> </foaf:knows>
</rdf:Description></rdf:RDF>
Typed Nodes in RDF/XML
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"xmlns:foaf="http://xmlns.com/foaf/0.1/">
<rdf:Description rdf:about="http://www.yahoo.com/~jdoe#jane"><rdf:type rdf:resource="http://xmlns.com/foaf/0.1/Person" /> <foaf::name>Jane Doe</foaf:name>
</rdf:Description> </rdf:RDF> Jane is an instance of Person
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"xmlns:foaf="http://xmlns.com/foaf/0.1/">
<foaf:Person rdf:about="http://www.yahoo.com/~jdoe#jane"><foaf::name>Jane Doe</foaf:name>
</foaf:Person> </rdf:RDF>
Shorthand for the same thing
RDFa
<html xmlns="http://www.w3.org/1999/xhtml" prefix="bibo: http://purl.org/ontology/bibo/ dc: http://purl.org/dc/terms/" > <head> <title>Books by Marco Pierre White</title> </head> <body> I think White's book '<span about="urn:ISBN:0091808189" typeof="bibo:Book" property="dc:title">Canteen Cuisine</span>' is well worth getting since although it's quite advanced stuff, he makes it pretty easy to follow. You might also like <span about="urn:ISBN:1596913614" typeof="bibo:Book" property="dc:description" >White's autobiography</span>. </body></html>
Declare namespace prefixes
This item is of type Book, and has title “Canteen Cuisine”
This item is of type Book, and has description “White’s autobiography”
Example from http://www.w3.org/TR/rdfa-syntax/
RDF Schema Example
<rdf:RDF xml:base="http://example.org/univ-ont#"xmlns:rdf="http://www.w3.org/1999/02/22-rdf-
syntax-ns#"xmlns:rdfs="http://www.w3.org/2000/01/rdf-
schema#" xmlns:univ="http://example.org/univ-ont#">
<rdf:Property rdf:about="#teaches"><rdfs:domain rdf:resource="#Professor" /><rdfs:range rdf:resource="#Course" />
</rdf:Property><univ:Person rdf:about="#heflin" >
<univ:teaches rdf:resource="#cse428" />
</univ:Person></rdf:RDF>
teaches
Course
Professor
heflin cse428
rdf:Property
teaches
rdf:type
rdfs:domain
rdfs:range
