RDF (Resource Description Framework)
2 Table of Contents Introduction Basic RDF –Basic RDF Model –Basic Syntax Containers Statements about Statements examples
3 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.
4 Introduction using –Resource discovery. –Digital library. –Intelligent software agents. –Privacy Policies. –Etc..
5 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
6 Basic RDF Model No2 Resources –ALL things being described by RDF expressions are called resources Properties –A Property is a specific aspect, characteristic, attribute or 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
7 Basic RDF Model No3 Subject(Resource) Predicate(Propery)Creator Object(literal)“Ora Lassila” sentence Ora Lassila the creator of the resource
8 Basic RDF Model (Simple node and arc diagram) Ora Lassila Creator The graph consists of two nodes connected by a single arc. One node (represented as an oval) contains the URI text and the other (represented as a rectangle) contains the text "Ora Lassila". The arc connecting these nodes bears the label Creator.
9 Basic RDF Model (Property with structured Value) Creator Ora Lassila Name sentence The individual whose name is Ora Lassila, , is the creator of
10 Basic RDF Model (Structured value with identifier) Creator Ora Lassila Name sentence The individual referred to by employee id is named Ora Lassila and has the address The resource was created by this individual.
11 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
12 Basic RDF Syntax No2 Serialization Syntax Express –The RDF XML syntax has been designed to accomodate 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
13 Serialization Syntax Express sentence Ora Lassila is the creator of the resourcehttp:// <rdf:RDF xmlns:rdf = “ xmlns:s = “ “ > Ora Lassila
14 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
15 Abbreviated Syntax Express World Wide Web Consortium W3C Home Page T02:27 <rdf:Description about=" s:Publisher="World Wide Web Consortium" s:Title="W3C Home Page" s:Date=" T02:27"/>
16 Abbreviated Syntax Express The second RDF abbreviation form works on nested Description elements Sentence The individual referred to by employee id is named Ora Lassila and has the address The resource was created by this individual.
17 Abbreviated Syntax Express Ora Lassila
18 Abbreviated Syntax Express Ora Lassila
19 Abbreviated Syntax Express <s:Creator rdf:resource=" v:Name="Ora Lassila" />
20 Abbreviated Syntax Express <rdf:RDF xmlns:rdf=" xmlns:s=" Ora Lassila
21 Abbreviated Syntax Express Ora Lassila
22 Reference W3C RDF – –Resource Description Framework (RDF) Model and Syntax Specification