RDF(Resource Description Framework) 연세대학교 이승익

MOTIVATION The Right Way to Find Things »Scenario 1: The Library »Scenario 2: The Video Store »Scenario 3: The Phone Book What About the Web?

RDF 용어 소개 Resource »Anything that can have a URI »World's Web pages »Individual elements of an XML document »Example : Property »Author or Title Value : The value of Property »Tim Bray

META DATA(1) Ora Lassila is the creator of the resource

METADATA(2) The individual whose name is Ora Lassila, , is the creator of

METADATA(3) The individual referred to by employee id is named Ora Lassila and has the address The resource was created by this individual.

Basic RDF Serialization Syntax [1] RDF ::= [' '] description* [' '] [2] description ::= ' ' propertyElt* ' ' [3] idAboutAttr ::= idAttr | aboutAttr [4] aboutAttr ::= 'about="' URI-reference '"' [5] idAttr ::= 'ID="' IDsymbol '"' [6] propertyElt ::= ' ' value ' ' | ' ' [7] propName ::= Qname [8] value ::= description | string [9] resourceAttr ::= 'resource="' URI-reference '"' [10] Qname ::= [ NSprefix ':' ] name [11] URI-reference ::= string, interpreted per [URI] [12] IDsymbol ::= (any legal XML name symbol) [13] name ::= (any legal XML name symbol) [14] NSprefix ::= (any legal XML namespace prefix) [15] string ::= (any XML text, with " ", and "&" escaped)

FIRST RDF REPRESENTATION Ora Lassila is the creator of the resource <rdf:RDF xmlns:rdf=" xmlns:s=" Ora Lassila

ABBREVIATION SYNTAX Ora Lassila <rdf:Description about=" s:Creator="Ora Lassila" />

SCHEMA & NAMESPACE RDF 문장의 동일한 해석 (Creator, Copyright) RDF 문장에 쓰이는 용어를 정의 특정 스키마를 지칭하기 위해 namespace 사용

CONTAINERS Bag »An ordered list of resources or literals Sequence »An ordered list of resources or literals Alternative »Alternatives for the value of a property

BAG The students in course are Amy, Tim, John, Mary, and Sue

ALTERNATIVE The source code for X11 may be found at ftp.x.org, ftp.cs.purdue.edu, or ftp.eu.net

CONTAINERS DEFINED BY A URI PATTERN ⓒ 1998, The Foo Organization ⓒ 1998, The Foo Organization

DISTRIBUTIVE REFERENT Ora Lassila Ora Lassila

RDF 의 표현력 정리 Multiple Metadata Schemas Multiple Values »Container Can Describe the Metadata Can be embed in HTML »Using abbreviation form RDF Schemas »RDF 의 property 에 정확한 의미 부여, 사용 가능한 용어 정의

정리 Standard mechanism for the global exchange of metadata and their schemas 장점 »focus on the issues of semantics rather than the syntax and structure of metadata »Re-use, extendibility and refinement of established resource description standards since these will be available in machine- readable form 예상 효과 »Improving the deployability of advanced Web applications