1. 시맨틱 웹 VoCamp 서울: 여름
온톨로지 개념 및
온톨로지 표현언어
김동범 (eastkim@gmail.com)
아이네크 시맨틱사업팀
http://www.dbdb.kr, @eastkim on twitter
2009.05.29
1

2. The Role of RDF on Semantic Web
Semantic
Aspect
시맨틱 웹 표준의
첫 번째 Layer
Web
Aspect
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3. Why RDF model is different from the
XML model ?
 “The author of the page is Ora”
 triple(author, page, Ora)
has author
page Ora
Tim Berners-Lee (1998), http://www.w3.org/DesignIssues/RDF-XML
시맨틱 웹 VoCamp 서울: 여름 -3-

4. How would this information be typically represented
in XML?
or may be
<author> <document>
<uri>page</uri> <details>
<uri>href=“page”</uri>
<name>Ora</name>
<author>
</author> <name>Ora</name>
</author>
</details>
or may be </document>
<document href=“page”>
<author>Ora</author> <document>
</document> <author>
<uri>href=“page”</uri>
<details>
<name>Ora</name>
</details>
</author>
</document>
or may be
<document href=“http://www.w3.org/test/page” author=“Ora” />
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5. What is the author of page?
<v>
<x>
<y>a=“pppp”</y>
<z>
<w>qqqqq</w>
</z>
</x>
</v>
has author
page Ora
b
a c
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6. In RDF Graph
<Description about=quot;http://www.w3.org/test/pagequot; Author =quot;Oraquot; />
<?xml version=quot;1.0quot;?>
<Description about=quot;http://www.w3.org/test/page“>
<s:Author =quot;http://www.w3.org/staff/Oraquot; />
</Description>
has author
page Ora
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7. The RDF Graph displays the same thing
<Description about=“xquot; y=“z” />
<?xml version=quot;1.0quot;?>
<Description about=“x“>
<y =“z” />
</Description>
y
x z
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8. 분산된 데이터의 웹에서….
글을 영화 ‘xxx’에
작성하다 출연하다
통합문서
Ora는 ‘page’의
저자이고, 영화 ‘xxx’에
출연했다
xxx
has author
page Ora plays in
시맨틱 웹 VoCamp 서울: 여름 -8-

9. What is ontology?
quot;formal, explicit specification of a
shared conceptualization“
“공유된 개념에 대한 형식적이고,
명시적인 명세……??”
Tom Gruber (1993)
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10. What is ontology?
존재론 in Philosophy
즉, 온톨로지는 “존재하는 것들에 대한 설명”
그럼 존재하는 것이란 무엇일까요?
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11. 존재하는 것
Thing
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12. 스무고개…
Asia
partOf
Person
lives in
type Korea
Asia
age
Thing
works at
3X INEK
name
type
??
Corporation
정답!! >> 김동범
시맨틱 웹 VoCamp 서울: 여름 - 12 -

13. 이와 같이 온톨로지는….
 Thing 에 제약(속성, 관계)을 가함으로써 개념을 정의
 제약이 많다 = 표현력(Expressivity)이 풍부하다
 객관적인 형식과 그 형식이 동작하는 방식을 규정 (formal)
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14. 표현력에 따른 온톨로지
 Lightweight ontologies  Heavyweight ontologies
 Concepts  type constraints on relations
 Relationships between  Cardinality constraints
Concepts
 Axioms
 IS-A Hierarchy
RDF, RDFS, OWL Lite OWL DL
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15. 온톨로지 표현 언어
RDF, RDFS, OWL
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16. History of Ontology Language
 RDF(S)
 Developed by W3C (1999, 02)
 Ontology Inference Layer : OIL
 Developed by group of European researchers (2000, 01)
 DAML Ontology Language : DAML-ONT
 Developed by US researchers working in DAML program (2000, 10)
 Effort merged in DAML+OIL
 Developed by EU/US joint committee (2000, 12)
 W3C Web Ontology group : OWL
 W3C standard based on DAML+OIL (2002, 02)
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17. RDF stands for
Resource : URI를 갖는 모든 것 (웹 페이지, 이미지, 동영상 등)
Description : 자원(Resource)들의 속성, 특성, 관계
Framework : 위의 것들을 기술하기 위한 모델, 언어, 문법
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18. RDF 데이타 모델
Predicate
Subject Object : Triple Model
example
title
온톨로지 개념 및 표현언어
http://www.dbdb.kr/rdf_tutorial
author DongBeom Kim
<?xml version=“1.0”>
<RDF>
<Description about=“http://www.dbdb.kr/rdf_tutorial”>
<author>DongBeom Kim</author>
<homepage>온톨로지 개념 및 표현언어</homepage>
</Description>
</RDF>
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19. Movie List
URI : http://movie.naver.com/
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20. RDF Example
title director country runtime genre reviewer
007 퀀텀 오브 솔러스 마크 포스터 미국 106분 액션 genie
아내가 결혼했다 정윤수 한국 119분 멜로 eastkim
… … … … … …
<?xml version=“1.0”>
<RDF xmlns:rdf=“http://www.w3.org/1999/02/22-rdf-syntax-ns#”
xmlns:movie=“http://movie.naver.com/”>
<Description rdf:about=“http://movie.naver.com/007quantumofsolace”>
<movie:title>007 퀀텀 오브 솔러스</movie:title>
<movie:director>마크 포스터</movie:director>
<movie:country>미국</movie:country>
<movie:runtime>106분</movie:runtime>
<movie:reviewer>genie</movie:reviewer>
</Description>
<Description rdf:about=“http://movie.naver.com/2husbands”>
<movie:title>아내가 결혼했다</movie:title>
…
</Description>
</RDF>
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21. RDF Main Elements
<rdf:RDF> Element
RDF 문서의 root Element
<rdf:Description> Element
about 속성을 가진 resource를 식별(기술)하기 위해 사용
Resource를 기술하기 위한 여러 Element(title, director, etc)를 포함
<?xml version=“1.0”>
<RDF xmlns:rdf=“http://www.w3.org/1999/02/22-rdf-syntax-ns#”
xmlns:movie=“http://movie.naver.com/”>
<Description rdf:about=“http://movie.naver.com/007quantumofsolace”>
.
<movie:title>007 goes 오브 솔러스</movie:title>
. Description 퀀텀 here
<movie:director>마크 포스터</movie:director>
.
<movie:country>미국</movie:country>
<movie:runtime>106분</movie:runtime>
<movie:reviewer>genie</movie:reviewer>
</Description>
<Description rdf:about=“http://movie.naver.com/2husbands”>
<movie:title>아내가 결혼했다</movie:title>
…
</Description>
</RDF>
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22. RDF Main Elements
 Properties as Attributes
<Description rdf:about=“http://movie.naver.com/007quantumofsolace”
movie:title=“007 퀀텀 오브 솔러스” movie:director=“마크 포스터”
movie:country=“미국” movie:runtime=“106분” movie:reviewer=“genie”
/>
 Properties as Resources
<Description rdf:about=“http://movie.naver.com/007quantumofsolace”>
<movie:title>007 퀀텀 오브 솔러스</movie:title>
<movie:director>마크 포스터</movie:director>
<movie:country>미국</movie:country>
<movie:runtime>106분</movie:runtime>
<movie:reviewer>genie</movie:reviewer>
</Description>
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23. RDF Main Elements
 rdf:
Alt, Bag, Description, ID, List, Property, Statement, Seq, XMLLiteral
about, first, nodeID, object, parseType, predicate, resource, rest, subject, type,
value, nil
 rdfs
:
Class, Container, ContainerMembershipProperty, Datatype, Literal, Resource
comment, domain, isDefinedBy, label, member, range, sellAlso, subClassOf, subPropertyOf
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24. OWL (Web Ontology Language)
 More Expressive than RDF(S)
 Adds more vocabularies for describing properties
and classes
 Based on Description Logic
 W3C Recommendation (2004.02)
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25. OWL 의 하위 언어들
 OWL Lite
 Subset of DL
 light-weight 한 ontology 구축에 적합
 OWL DL
 Support Description Logic segment
 Has properties for reasoning systems
 heavy-weight한 ontology 구축에 적합
 OWL Full
 Union of OWL and RDFS
 Allow free mixing of OWL with RDF Schema
 Not enforce a strict separation of classes, properties, individuals
 OWL Lite ⊂ DL ⊂ Full
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26. OWL Lite Contructions (1)
 RDF Schema Features:  (In)Equality
 Class  equivalentClass
 rdf:Property  equivalentProperty
 rdfs:subClassOf  sameIndividualAs
 rdfs:subPropertyOf
 differentFrom
 rdfs:domain
 allDifferent
 rdfs:range
 Individual
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27. OWL Lite Contructions (2)
 Property Type  Restricted Cardinality
Restrictions: – minCardinality (only 0 or 1)
 allValuesFrom – maxCardinality(only 0 or 1)
 someValuesFrom – cardinality (only 0 or 1)
 Class Intersection  Property Characteristics:
 intersectionOf  inverseOf
 transitiveProperty
 Datatypes  symmetricProperty
 functionalPropety
 InverseFunctionalProperty
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28. Property type restrictions
 owl:allValuesFrom
<owl:Restriction>
<owl:onProperty rdf:resource=quot;#hasParentquot; />
<owl:allValuesFrom rdf:resource=quot;#Humanquot; />
</owl:Restriction>
hasParent
X Y
Y는 모두 Human
 owl:someValuesFrom : 부모중 적어도 한명은 Physician 이다.
<owl:Restriction>
<owl:onProperty rdf:resource=quot;#hasParentquot; />
<owl:someValuesFrom rdf:resource=quot;#Physicianquot;/>
</owl:Restriction>
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29. Property type restrictions
 owl:inverseOf
if hasChild inverseOf hasParent and Deborah hasParent Louise
then Louise hasChild Deborah
 owl:transitiveProperty
if pair(X,Y), pair(Y,Z) are instances of transitive property P,
then pair(X,Z) is also instance of P
 owl:symmetricProperty
if pair(X,Y) is an instance of P, then pair(Y,X) is also instance of P
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30. OWL DL, FULL Contructions
(2) Axioms:
 Class Boolean Combinations 
 oneOf of Class Expressions:
 disjointWith – unionOf
 equivalentClass – intersectionOf
(applied to class expressions) – complementOf
 rdfs:subClassOf
(applied to class expressions)
 Filler Information:
 Arbitrary Cardinality:
– hasValue
 minCardinality
 maxCardinality
 cardinality
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31. OWL DL 표현 예제
 owl:intersectionOf
 links a class to a list of class description
 represent the “AND”
<owl:Class rdf:ID=quot;Adultquot;>
<owl:intersectionOf rdf:parseType=quot;Collectionquot;>
<owl:Class rdf:about=quot;#Personquot;/>
<owl:restriction>
<owl:onProperty rdf:resource=quot;#agequot;/>
<owl:someValuesFrom
df:resource=quot;http://www.w3.org/TR/@@/owl-ex-dt#over19quot;/>
</owl:Restriction>
</owl:intersectionOf>
</owl:Class>
Adult = Person ∩ $ age.over19
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32. OWL DL 표현 예제
 owl:inverseOf
<owl:ObjectProperty rdf:ID=“hasChild”>
<owl:inverseOf rdf:resource=“#hasParent”/>
</owl:ObjectProperty>
 owl:FunctionalProperty
<owl:FunctionalProperty rdf:ID=quot;husbandquot;>
<rdfs:domain rdf:resource=quot;#Womanquot; />
<rdfs:range rdf:resource=quot;#Manquot; />
</owl:FunctionalProperty>
<owl:ObjectProperty rdf:ID=quot;husbandquot;>
<rdf:type rdf:resource=quot;&owl;FunctionalPropertyquot; />
<rdfs:domain rdf:resource=quot;#Womanquot; />
<rdfs:range rdf:resource=quot;#Manquot; />
</owl:ObjectProperty>
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33. OWL DL 표현 예제
 owl:TransitiveProperty
<owl:TransitiveProperty rdf:ID=quot;subRegionOfquot;>
<rdfs:domain rdf:resource=quot;#Regionquot;/>
<rdfs:range rdf:resource=quot;#Regionquot;/>
</owl:TransitiveProperty>
 owl:SymmetricProperty
<owl:SymmetricProperty rdf:ID=quot;friendOfquot;>
<rdfs:domain rdf:resource=quot;#Humanquot;/>
<rdfs:range rdf:resource=quot;#Humanquot;/>
</owl:SymmetricProperty>
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34. 시맨틱 웹 VoCamp 서울: 여름
감사합니다 !
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