SlideShare a Scribd company logo
Nifty Features of OWL 2(Or, yes I was on the OWLWG)Rinke Hoekstra
Why this topic?(… someone asked me …)Take home message“Sure, not everything about OWL 2 is great, but it does add some very nice new features that we can all use and learn to love”
Playing The Devil’s AdvocateWhere’s the Web in OWL? Where’s the Ontology in OWL?“OL” or “WL”OWL DL and OWL Full“OWLDLED”“OWL is a description logic”OWL and Rules“Rules are just more intuitive”“People think in rules”OWL and Philosophy“OWL is philosophically flawed”OWL 2 DL and reasoning“Decidability is hugely overrated”“Consistency does not exist on the web”“OWL reasoners even die on very small knowledge bases”“I only need part of OWL, so why implement a fully OWL compliant reasoner”Expressiveness“OWL is not expressive enough for my needs”“OWL is way too expressive, no-one will ever need that”“The only useful addition of OWL to RDF is owl:sameAs”
DISCLAIMERDo not be confused by OWL 2 (or any other W3C standard)In the end, every standard is a compromise;the result of a `political’ debate between different communities, and not technical insight.Compatible revisions of existing standards inherit political issues, misconceptions, and then add some of their ownIt’s just that if the communities are technical, you end up with a `technical’ standard.
DISCLAIMER For OWL 2 this means:Replaces OWL 1, but is compatibleSpecies inheritance, includingOWL DL vs. OWL Full debateCompatibility with other W3C standardsSocial ‘issues’ with WG:Over-representation of DL communityUnder-representation of RDF/SW community
Economics of OWL 2Technology pushAdvancements in Description Logics researchMarket pullExperiencesAdded expressivenessOther syntaxesBetter (‘easier’) tool developmentCaters for several communitiesHC, LS, KR, SW, Engineering, Enterprise Systems
BackgroundOWLED workshops (60-70 people)First one in 2005Users, industry, researchW3C Member submission: OWL 1.1December 2006, following vote at OWLED 2006OWL Working GroupNovember 2007, following vote at OWLED 2007OWL 2 RecommendationOctober 2009
Before
During
After
Back on topic…Language DesignProfilesExchange SyntaxesNifty FeaturesDatatypecoolnessProperties & RestrictionsSyntactic SugarPunningAnnotationsBonus material
Language Design (1)OWL 1: Abstract SyntaxFrame-basedDL: axioms, Full: rules… then why frames?Hard to use for defining semanticsto parseto extend“an OWL ontology is an RDF graph”OWL 2: Structural SpecificationAxiom centredUML/MOF data model“an OWL 2 ontology is an instance O of the Ontology UML class”“any OWL 2 ontology can also be viewed as an RDF graph”OWL 2: Functional Style Syntax BNF grammarhttp://www.w3.org/TR/owl2-syntax/
Language Design (2)OWL 1: SpeciesLite, DL, FullConfusion between semantics and syntaxOWL Lite? Nah…OWL 2: SemanticsDirect Semantics (DL), http://www.w3.org/TR/owl-direct-semanticsRDF-Based Semantics (Full), http://www.w3.org/TR/owl-rdf-based-semanticsMost OWL 2 DL ontologies are OWL 1 Full
ProfilesOWLs living in the swamps of AmsterdamOWL 2 EL Polynomial time algorithms for standard reasoning tasks; Large ontologies (TBox)OWL 2 QL Conjunctive query answering in in LogSpace using RDB technology;Lightweight ontologies that organize many individualsAccess the data directly via relational queries (e.g., SQL). OWL 2 RL(a.k.a. RDFS 3.0 ?)Polynomial time algorithms using rule-extended DB technologiesLightweight ontologies that organize many individualsOperate directly on RDF triplesRule set provided by specificationSemantics follows from syntactic restrictionsExtra “global restrictions” for OWL 2 DL, QL and ELExtensible!
Exchange SyntaxesOWL 1: RDF/XML (2004)W3C Note: OWL XML Syntax (2003)OWL 2: RDF/XML (mandatory)TurtleFunctional Style SyntaxOWL XML (2009) (+ mandatory GRDDL transformation)Manchester Syntax
Hey, show me those nifty features already!Yeah yeah…
Datatypes (1)Extended XML Schema compatibilityNew datatypes not in XML Schemaowl:real, owl:rationalDatatype definitionsxsd:minInclusive, xsd:maxInclusive, xsd:minExclusive, xsd:maxExclusivexsd:pattern (e.g. regular expressions), xsd:lengthrdf:PlainLiteral(together with RIFWG)All RDF plain literalsNot to be used in syntaxes that already deal with RDF plain literalsDatatypeDefinition(  a:SSN    DatatypeRestriction(xsd:stringxsd:pattern "[0-9]{3}-[0-9]{2}-[0-9]{4}" ))
Datatypes(2)Datatype DefinitionsData Range CombinationsKeysOnly hold for named individualsDatatypeDefinition( :adultAgeDatatypeRestriction(xsd:integerminInclusive 18)DataComplementOf( :adultAge)DataUnionOf( :adultAge :studentAge)…HasKey( :Transplantation :donorId :recipientId :ofOrgan)
Datatypes (3)N-arydatatypesExtension (Working Group Note)http://www.w3.org/TR/owl2-dr-linear/Linear equationsDataAllValuesFrom ( :meltingPoint :boilingPointDataComparison(Arguments(xy) leq( xy ))))
Properties (1)Property TypesAsymmetric propertiesReflexive and Irreflexive propertiesTop and bottom propertiesProperty chainsSubObjectPropertyOf( ObjectPropertyChain( a:hasMothera:hasSister ) a:hasAunt)
Properties (2)Property AssertionsDisjointnessProperty restrictionsSelf Restriction (local reflexivity)Qualified Cardinality RestrictionsDatatype restrictions‘ObjectInverseOf’ in restrictionsObjectHasSelf( a:likes )DataSomeValuesFrom( a:hasAgeDatatypeRestriction( xsd:integerxsd:minInclusive “13”^^xsd:integer xsd:maxExclusive “20”^^xsd:integer ) )
Just an illustration (three, actually)SubObjectPropertyOf( ObjectPropertyChain ( a:isElephantowl:TopObjectPropertya:isMouse ) a:likes )
Syntactic SugarDisjoint UnionDisjoint ClassesNegative property assertionsDisjointUnion(:BrainHemisphere :LeftHemisphere :RightHemisphere)DisjointClasses( :LeftLung :RightLung)NegativeDataPropertyAssertion( :hasAge :Frank 50^^xsd:integer )EquivalentClasses ( ObjectOneOf( :Frank ) ObjectComplementOf ( DataHasValue( :hasAge 50^^xsd:integer )) )
Punning (wordplay)Any name can be used for any type of entityDirect SemanticsInterpreted as separate entitiesRDF-Based SemanticsInterpreted as the same entity… but no punning between:Datatype and Class namesData-, Object- and Annotation property names(actually supported by most implementations)ConsequenceStrongly typed syntax (FS, OWLXML)…but not in RDF graphs
AnnotationsNo semantics in Direct SemanticsSupported on all entitiesClasses, individuals, propertiesAxioms, annotations, ontologiesAnnotation axiomsAnnotation SubpropertiesDomain and RangeAnnotationAssertion (skos:prefLabel :SWMeeting “Semantic Web Meeting”@en )SubClassOf( Annotation( rdfs:comment ”Every SWMeeting is a Meeting.")												:SWMeeting :Meeting)
Imports & VersioningImport by location… but comes down to ‘just’ dereferencingOntologyIRI and VersionIRIOntologies should be accessible atOntologyIRIIf no VersionIRI supplied or if it is the latest versionVersionIRIIf a VersionIRI is suppliedImport statement may point to either
Other things…Internationalized Resource IdentifiersBNodes are existentialsGlobal restrictions for Direct SemanticsAnonymous individuals are BNodes… no change in RDFDeclarationsIndicate what ontology defines an entity… but mostly just nice for parsers, no change in RDFObjectPropertyAssertion(<http://example.org/p> <http://example.org/a> 											_:http://example.org/#genid-x)ClassAssertion(ObjectSomeValuesFrom(<http://example.org/p> owl:Thing) 												   <http://example.org/a>)
Bonus MaterialPretty decent outreach materialComprehensive OWL 2 Overviewhttp://www.w3.org/TR/owl-overview/OWL 2 Quick Reference Cardhttp://www.w3.org/TR/owl-quick-reference/OWL 2 Primerhttp://www.w3.org/TR/owl-primer/OWL 2 New Features and Rationalehttp://www.w3.org/TR/owl-new-features/OWL 2 Conformancehttp://www.w3.org/TR/owl-conformance
What I like about OWL 2Cleaner language designAdded expressivenessPropertiesDatatypesIncreased compatibility between Full and DLPunningAnnotation propertiesProfiles… most notably OWL 2 RL … hooks for extensibility

More Related Content

What's hot

SPIN in Five Slides
SPIN in Five SlidesSPIN in Five Slides
SPIN in Five Slides
Holger Knublauch
 
Integrating a Domain Ontology Development Environment and an Ontology Search ...
Integrating a Domain Ontology Development Environment and an Ontology Search ...Integrating a Domain Ontology Development Environment and an Ontology Search ...
Integrating a Domain Ontology Development Environment and an Ontology Search ...
Takeshi Morita
 
SHACL Specification Draft
SHACL Specification DraftSHACL Specification Draft
SHACL Specification Draft
Holger Knublauch
 
Tutorial OWL and drug discovery ICBO 2013
Tutorial OWL and drug discovery ICBO 2013Tutorial OWL and drug discovery ICBO 2013
Tutorial OWL and drug discovery ICBO 2013
Samuel Croset
 
NAMED ENTITY RECOGNITION
NAMED ENTITY RECOGNITIONNAMED ENTITY RECOGNITION
NAMED ENTITY RECOGNITION
live_and_let_live
 
Semantic web Technology
Semantic web TechnologySemantic web Technology
Semantic web Technology
Abdelrahman Ibrahim
 
ShEx vs SHACL
ShEx vs SHACLShEx vs SHACL
ShEx vs SHACL
Jose Emilio Labra Gayo
 
Introduction to search engine-building with Lucene
Introduction to search engine-building with LuceneIntroduction to search engine-building with Lucene
Introduction to search engine-building with Lucene
Kai Chan
 
Introduction to libre « fulltext » technology
Introduction to libre « fulltext » technologyIntroduction to libre « fulltext » technology
Introduction to libre « fulltext » technology
Robert Viseur
 
Introduction to search engine-building with Lucene
Introduction to search engine-building with LuceneIntroduction to search engine-building with Lucene
Introduction to search engine-building with Lucene
Kai Chan
 
EDF2012 Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...
EDF2012   Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...EDF2012   Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...
EDF2012 Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...
European Data Forum
 
A hands on overview of the semantic web
A hands on overview of the semantic webA hands on overview of the semantic web
A hands on overview of the semantic web
Marakana Inc.
 
Abstract Access Control Model for Dynamic RDF Datasets
Abstract Access Control Model for Dynamic RDF DatasetsAbstract Access Control Model for Dynamic RDF Datasets
Abstract Access Control Model for Dynamic RDF Datasets
PlanetData Network of Excellence
 
SPIN and Shapes
SPIN and ShapesSPIN and Shapes
SPIN and Shapes
Holger Knublauch
 
Perl%20Tutorial.!Picking%20Up%20Perl
Perl%20Tutorial.!Picking%20Up%20PerlPerl%20Tutorial.!Picking%20Up%20Perl
Perl%20Tutorial.!Picking%20Up%20Perl
tutorialsruby
 
Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)
Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)
Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)
Dr.-Ing. Thomas Hartmann
 
Martin Odersky - Evolution of Scala
Martin Odersky - Evolution of ScalaMartin Odersky - Evolution of Scala
Martin Odersky - Evolution of Scala
Scala Italy
 
Presentation of OpenNLP
Presentation of OpenNLPPresentation of OpenNLP
Presentation of OpenNLP
Robert Viseur
 

What's hot (18)

SPIN in Five Slides
SPIN in Five SlidesSPIN in Five Slides
SPIN in Five Slides
 
Integrating a Domain Ontology Development Environment and an Ontology Search ...
Integrating a Domain Ontology Development Environment and an Ontology Search ...Integrating a Domain Ontology Development Environment and an Ontology Search ...
Integrating a Domain Ontology Development Environment and an Ontology Search ...
 
SHACL Specification Draft
SHACL Specification DraftSHACL Specification Draft
SHACL Specification Draft
 
Tutorial OWL and drug discovery ICBO 2013
Tutorial OWL and drug discovery ICBO 2013Tutorial OWL and drug discovery ICBO 2013
Tutorial OWL and drug discovery ICBO 2013
 
NAMED ENTITY RECOGNITION
NAMED ENTITY RECOGNITIONNAMED ENTITY RECOGNITION
NAMED ENTITY RECOGNITION
 
Semantic web Technology
Semantic web TechnologySemantic web Technology
Semantic web Technology
 
ShEx vs SHACL
ShEx vs SHACLShEx vs SHACL
ShEx vs SHACL
 
Introduction to search engine-building with Lucene
Introduction to search engine-building with LuceneIntroduction to search engine-building with Lucene
Introduction to search engine-building with Lucene
 
Introduction to libre « fulltext » technology
Introduction to libre « fulltext » technologyIntroduction to libre « fulltext » technology
Introduction to libre « fulltext » technology
 
Introduction to search engine-building with Lucene
Introduction to search engine-building with LuceneIntroduction to search engine-building with Lucene
Introduction to search engine-building with Lucene
 
EDF2012 Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...
EDF2012   Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...EDF2012   Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...
EDF2012 Irini Fundulaki - Abstract Access Control Models for Dynamic RDF Da...
 
A hands on overview of the semantic web
A hands on overview of the semantic webA hands on overview of the semantic web
A hands on overview of the semantic web
 
Abstract Access Control Model for Dynamic RDF Datasets
Abstract Access Control Model for Dynamic RDF DatasetsAbstract Access Control Model for Dynamic RDF Datasets
Abstract Access Control Model for Dynamic RDF Datasets
 
SPIN and Shapes
SPIN and ShapesSPIN and Shapes
SPIN and Shapes
 
Perl%20Tutorial.!Picking%20Up%20Perl
Perl%20Tutorial.!Picking%20Up%20PerlPerl%20Tutorial.!Picking%20Up%20Perl
Perl%20Tutorial.!Picking%20Up%20Perl
 
Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)
Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)
Doctoral Examination at the Karlsruhe Institute of Technology (08.07.2016)
 
Martin Odersky - Evolution of Scala
Martin Odersky - Evolution of ScalaMartin Odersky - Evolution of Scala
Martin Odersky - Evolution of Scala
 
Presentation of OpenNLP
Presentation of OpenNLPPresentation of OpenNLP
Presentation of OpenNLP
 

Similar to Vu Semantic Web Meeting 20091123

Semantic Web: From Representations to Applications
Semantic Web: From Representations to ApplicationsSemantic Web: From Representations to Applications
Semantic Web: From Representations to Applications
Guus Schreiber
 
eswc2011phd-schneid
eswc2011phd-schneideswc2011phd-schneid
eswc2011phd-schneid
Michael Schneider
 
Semantic web
Semantic webSemantic web
Semantic web
tariq1352
 
Web ontology language (owl)
Web ontology language (owl)Web ontology language (owl)
Web ontology language (owl)
Ameer Sameer
 
eureka09
eureka09eureka09
eureka09
tutorialsruby
 
eureka09
eureka09eureka09
eureka09
tutorialsruby
 
Ontology Engineering
Ontology EngineeringOntology Engineering
Ontology Engineering
Alessandro Adamou
 
BT02.pptx
BT02.pptxBT02.pptx
BT02.pptx
ThAnhonc
 
Ontologies and Vocabularies
Ontologies and VocabulariesOntologies and Vocabularies
Ontologies and Vocabularies
seanb
 
cade23-schneidsut-atp4owlfull-2011
cade23-schneidsut-atp4owlfull-2011cade23-schneidsut-atp4owlfull-2011
cade23-schneidsut-atp4owlfull-2011
Michael Schneider
 
Making the semantic web work
Making the semantic web workMaking the semantic web work
Making the semantic web work
Paul Houle
 
Structured Dynamics' Semantic Technologies Product Stack
Structured Dynamics' Semantic Technologies Product StackStructured Dynamics' Semantic Technologies Product Stack
Structured Dynamics' Semantic Technologies Product Stack
Mike Bergman
 
The Standardization of Semantic Web Ontology
The Standardization of Semantic Web OntologyThe Standardization of Semantic Web Ontology
The Standardization of Semantic Web Ontology
Myungjin Lee
 
Rinke Owl Uml 20040428
Rinke Owl Uml 20040428Rinke Owl Uml 20040428
Rinke Owl Uml 20040428
Rinke Hoekstra
 
Services semantic technology_terminology
Services semantic technology_terminologyServices semantic technology_terminology
Services semantic technology_terminology
Tenforce
 
Owl web ontology language
Owl  web ontology languageOwl  web ontology language
Owl web ontology language
hassco2011
 
Owl web ontology language
Owl  web ontology languageOwl  web ontology language
Owl web ontology language
hassco2011
 
RDF briefing
RDF briefingRDF briefing
RDF briefing
Frank van Harmelen
 
Semantics
SemanticsSemantics
KIT Graduiertenkolloquium 11.05.2016
KIT Graduiertenkolloquium 11.05.2016KIT Graduiertenkolloquium 11.05.2016
KIT Graduiertenkolloquium 11.05.2016
Dr.-Ing. Thomas Hartmann
 

Similar to Vu Semantic Web Meeting 20091123 (20)

Semantic Web: From Representations to Applications
Semantic Web: From Representations to ApplicationsSemantic Web: From Representations to Applications
Semantic Web: From Representations to Applications
 
eswc2011phd-schneid
eswc2011phd-schneideswc2011phd-schneid
eswc2011phd-schneid
 
Semantic web
Semantic webSemantic web
Semantic web
 
Web ontology language (owl)
Web ontology language (owl)Web ontology language (owl)
Web ontology language (owl)
 
eureka09
eureka09eureka09
eureka09
 
eureka09
eureka09eureka09
eureka09
 
Ontology Engineering
Ontology EngineeringOntology Engineering
Ontology Engineering
 
BT02.pptx
BT02.pptxBT02.pptx
BT02.pptx
 
Ontologies and Vocabularies
Ontologies and VocabulariesOntologies and Vocabularies
Ontologies and Vocabularies
 
cade23-schneidsut-atp4owlfull-2011
cade23-schneidsut-atp4owlfull-2011cade23-schneidsut-atp4owlfull-2011
cade23-schneidsut-atp4owlfull-2011
 
Making the semantic web work
Making the semantic web workMaking the semantic web work
Making the semantic web work
 
Structured Dynamics' Semantic Technologies Product Stack
Structured Dynamics' Semantic Technologies Product StackStructured Dynamics' Semantic Technologies Product Stack
Structured Dynamics' Semantic Technologies Product Stack
 
The Standardization of Semantic Web Ontology
The Standardization of Semantic Web OntologyThe Standardization of Semantic Web Ontology
The Standardization of Semantic Web Ontology
 
Rinke Owl Uml 20040428
Rinke Owl Uml 20040428Rinke Owl Uml 20040428
Rinke Owl Uml 20040428
 
Services semantic technology_terminology
Services semantic technology_terminologyServices semantic technology_terminology
Services semantic technology_terminology
 
Owl web ontology language
Owl  web ontology languageOwl  web ontology language
Owl web ontology language
 
Owl web ontology language
Owl  web ontology languageOwl  web ontology language
Owl web ontology language
 
RDF briefing
RDF briefingRDF briefing
RDF briefing
 
Semantics
SemanticsSemantics
Semantics
 
KIT Graduiertenkolloquium 11.05.2016
KIT Graduiertenkolloquium 11.05.2016KIT Graduiertenkolloquium 11.05.2016
KIT Graduiertenkolloquium 11.05.2016
 

More from Rinke Hoekstra

Knowledge Representation on the Web
Knowledge Representation on the WebKnowledge Representation on the Web
Knowledge Representation on the Web
Rinke Hoekstra
 
Managing Metadata for Science and Technology Studies: the RISIS case
Managing Metadata for Science and Technology Studies: the RISIS caseManaging Metadata for Science and Technology Studies: the RISIS case
Managing Metadata for Science and Technology Studies: the RISIS case
Rinke Hoekstra
 
An Ecosystem for Linked Humanities Data
An Ecosystem for Linked Humanities DataAn Ecosystem for Linked Humanities Data
An Ecosystem for Linked Humanities Data
Rinke Hoekstra
 
QBer - Connect your data to the cloud
QBer - Connect your data to the cloudQBer - Connect your data to the cloud
QBer - Connect your data to the cloud
Rinke Hoekstra
 
Jurix 2014 welcome presentation
Jurix 2014 welcome presentationJurix 2014 welcome presentation
Jurix 2014 welcome presentation
Rinke Hoekstra
 
Provenance and Reuse of Open Data (PILOD 2.0 June 2014)
Provenance and Reuse of Open Data (PILOD 2.0 June 2014)Provenance and Reuse of Open Data (PILOD 2.0 June 2014)
Provenance and Reuse of Open Data (PILOD 2.0 June 2014)
Rinke Hoekstra
 
Prov-O-Viz: Interactive Provenance Visualization
Prov-O-Viz: Interactive Provenance VisualizationProv-O-Viz: Interactive Provenance Visualization
Prov-O-Viz: Interactive Provenance Visualization
Rinke Hoekstra
 
Linkitup: Link Discovery for Research Data
Linkitup: Link Discovery for Research DataLinkitup: Link Discovery for Research Data
Linkitup: Link Discovery for Research Data
Rinke Hoekstra
 
A Network Analysis of Dutch Regulations - Using the Metalex Document Server
A Network Analysis of Dutch Regulations - Using the Metalex Document ServerA Network Analysis of Dutch Regulations - Using the Metalex Document Server
A Network Analysis of Dutch Regulations - Using the Metalex Document Server
Rinke Hoekstra
 
Linked (Open) Data - But what does it buy me?
Linked (Open) Data - But what does it buy me?Linked (Open) Data - But what does it buy me?
Linked (Open) Data - But what does it buy me?
Rinke Hoekstra
 
Linked Science - Building a Web of Research Data
Linked Science - Building a Web of Research DataLinked Science - Building a Web of Research Data
Linked Science - Building a Web of Research Data
Rinke Hoekstra
 
COMMIT/VIVO
COMMIT/VIVOCOMMIT/VIVO
COMMIT/VIVO
Rinke Hoekstra
 
Semantic Representations for Research
Semantic Representations for ResearchSemantic Representations for Research
Semantic Representations for Research
Rinke Hoekstra
 
A Slightly Different Web of Data
A Slightly Different Web of DataA Slightly Different Web of Data
A Slightly Different Web of Data
Rinke Hoekstra
 
The Knowledge Reengineering Bottleneck
The Knowledge Reengineering BottleneckThe Knowledge Reengineering Bottleneck
The Knowledge Reengineering Bottleneck
Rinke Hoekstra
 
Linked Census Data
Linked Census DataLinked Census Data
Linked Census Data
Rinke Hoekstra
 
Concept- en Definitie Extractie
Concept- en Definitie ExtractieConcept- en Definitie Extractie
Concept- en Definitie Extractie
Rinke Hoekstra
 
SIKS 2011 Semantic Web Languages
SIKS 2011 Semantic Web LanguagesSIKS 2011 Semantic Web Languages
SIKS 2011 Semantic Web Languages
Rinke Hoekstra
 
The MetaLex Document Server - Legal Documents as Versioned Linked Data
The MetaLex Document Server - Legal Documents as Versioned Linked DataThe MetaLex Document Server - Legal Documents as Versioned Linked Data
The MetaLex Document Server - Legal Documents as Versioned Linked Data
Rinke Hoekstra
 
Querying the Web of Data
Querying the Web of DataQuerying the Web of Data
Querying the Web of Data
Rinke Hoekstra
 

More from Rinke Hoekstra (20)

Knowledge Representation on the Web
Knowledge Representation on the WebKnowledge Representation on the Web
Knowledge Representation on the Web
 
Managing Metadata for Science and Technology Studies: the RISIS case
Managing Metadata for Science and Technology Studies: the RISIS caseManaging Metadata for Science and Technology Studies: the RISIS case
Managing Metadata for Science and Technology Studies: the RISIS case
 
An Ecosystem for Linked Humanities Data
An Ecosystem for Linked Humanities DataAn Ecosystem for Linked Humanities Data
An Ecosystem for Linked Humanities Data
 
QBer - Connect your data to the cloud
QBer - Connect your data to the cloudQBer - Connect your data to the cloud
QBer - Connect your data to the cloud
 
Jurix 2014 welcome presentation
Jurix 2014 welcome presentationJurix 2014 welcome presentation
Jurix 2014 welcome presentation
 
Provenance and Reuse of Open Data (PILOD 2.0 June 2014)
Provenance and Reuse of Open Data (PILOD 2.0 June 2014)Provenance and Reuse of Open Data (PILOD 2.0 June 2014)
Provenance and Reuse of Open Data (PILOD 2.0 June 2014)
 
Prov-O-Viz: Interactive Provenance Visualization
Prov-O-Viz: Interactive Provenance VisualizationProv-O-Viz: Interactive Provenance Visualization
Prov-O-Viz: Interactive Provenance Visualization
 
Linkitup: Link Discovery for Research Data
Linkitup: Link Discovery for Research DataLinkitup: Link Discovery for Research Data
Linkitup: Link Discovery for Research Data
 
A Network Analysis of Dutch Regulations - Using the Metalex Document Server
A Network Analysis of Dutch Regulations - Using the Metalex Document ServerA Network Analysis of Dutch Regulations - Using the Metalex Document Server
A Network Analysis of Dutch Regulations - Using the Metalex Document Server
 
Linked (Open) Data - But what does it buy me?
Linked (Open) Data - But what does it buy me?Linked (Open) Data - But what does it buy me?
Linked (Open) Data - But what does it buy me?
 
Linked Science - Building a Web of Research Data
Linked Science - Building a Web of Research DataLinked Science - Building a Web of Research Data
Linked Science - Building a Web of Research Data
 
COMMIT/VIVO
COMMIT/VIVOCOMMIT/VIVO
COMMIT/VIVO
 
Semantic Representations for Research
Semantic Representations for ResearchSemantic Representations for Research
Semantic Representations for Research
 
A Slightly Different Web of Data
A Slightly Different Web of DataA Slightly Different Web of Data
A Slightly Different Web of Data
 
The Knowledge Reengineering Bottleneck
The Knowledge Reengineering BottleneckThe Knowledge Reengineering Bottleneck
The Knowledge Reengineering Bottleneck
 
Linked Census Data
Linked Census DataLinked Census Data
Linked Census Data
 
Concept- en Definitie Extractie
Concept- en Definitie ExtractieConcept- en Definitie Extractie
Concept- en Definitie Extractie
 
SIKS 2011 Semantic Web Languages
SIKS 2011 Semantic Web LanguagesSIKS 2011 Semantic Web Languages
SIKS 2011 Semantic Web Languages
 
The MetaLex Document Server - Legal Documents as Versioned Linked Data
The MetaLex Document Server - Legal Documents as Versioned Linked DataThe MetaLex Document Server - Legal Documents as Versioned Linked Data
The MetaLex Document Server - Legal Documents as Versioned Linked Data
 
Querying the Web of Data
Querying the Web of DataQuerying the Web of Data
Querying the Web of Data
 

Recently uploaded

"DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ...
"DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ..."DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ...
"DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ...
thanhluan21
 
Kesadaran_Berbangsa_dan_Bernegara_Nasion.pptx
Kesadaran_Berbangsa_dan_Bernegara_Nasion.pptxKesadaran_Berbangsa_dan_Bernegara_Nasion.pptx
Kesadaran_Berbangsa_dan_Bernegara_Nasion.pptx
artenzmartenkai
 
Node JS Interview Question PDF By ScholarHat
Node JS Interview Question PDF By ScholarHatNode JS Interview Question PDF By ScholarHat
Node JS Interview Question PDF By ScholarHat
Scholarhat
 
The Cruelty of Animal Testing in the Industry.pdf
The Cruelty of Animal Testing in the Industry.pdfThe Cruelty of Animal Testing in the Industry.pdf
The Cruelty of Animal Testing in the Industry.pdf
luzmilaglez334
 
C# Interview Questions PDF By ScholarHat.pdf
C# Interview Questions PDF By ScholarHat.pdfC# Interview Questions PDF By ScholarHat.pdf
C# Interview Questions PDF By ScholarHat.pdf
Scholarhat
 
Allopathic M1 Srudent Orientation Powerpoint
Allopathic M1 Srudent Orientation PowerpointAllopathic M1 Srudent Orientation Powerpoint
Allopathic M1 Srudent Orientation Powerpoint
Julie Sarpy
 
DepEd School Calendar 2024-2025 DO_s2024_008
DepEd School Calendar 2024-2025 DO_s2024_008DepEd School Calendar 2024-2025 DO_s2024_008
DepEd School Calendar 2024-2025 DO_s2024_008
Glenn Rivera
 
How to Manage Large Scrollbar in Odoo 17 POS
How to Manage Large Scrollbar in Odoo 17 POSHow to Manage Large Scrollbar in Odoo 17 POS
How to Manage Large Scrollbar in Odoo 17 POS
Celine George
 
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...
Nguyen Thanh Tu Collection
 
What is Rescue Session in Odoo 17 POS - Odoo 17 Slides
What is Rescue Session in Odoo 17 POS - Odoo 17 SlidesWhat is Rescue Session in Odoo 17 POS - Odoo 17 Slides
What is Rescue Session in Odoo 17 POS - Odoo 17 Slides
Celine George
 
JavaScript Interview Questions PDF By ScholarHat
JavaScript Interview  Questions PDF By ScholarHatJavaScript Interview  Questions PDF By ScholarHat
JavaScript Interview Questions PDF By ScholarHat
Scholarhat
 
MVC Interview Questions PDF By ScholarHat
MVC Interview Questions PDF By ScholarHatMVC Interview Questions PDF By ScholarHat
MVC Interview Questions PDF By ScholarHat
Scholarhat
 
E-learning Odoo 17 New features - Odoo 17 Slides
E-learning Odoo 17  New features - Odoo 17 SlidesE-learning Odoo 17  New features - Odoo 17 Slides
E-learning Odoo 17 New features - Odoo 17 Slides
Celine George
 
1. Importance_of_reducing_postharvest_loss.pptx
1. Importance_of_reducing_postharvest_loss.pptx1. Importance_of_reducing_postharvest_loss.pptx
1. Importance_of_reducing_postharvest_loss.pptx
UmeshTimilsina1
 
2 Post harvest Physiology of Horticulture produce.pptx
2 Post harvest Physiology of Horticulture  produce.pptx2 Post harvest Physiology of Horticulture  produce.pptx
2 Post harvest Physiology of Horticulture produce.pptx
UmeshTimilsina1
 
Genetics Teaching Plan: Dr.Kshirsagar R.V.
Genetics Teaching Plan: Dr.Kshirsagar R.V.Genetics Teaching Plan: Dr.Kshirsagar R.V.
Genetics Teaching Plan: Dr.Kshirsagar R.V.
DrRavindrakshirsagar1
 
Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)
Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)
Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)
Cátedra Banco Santander
 
SEQUNCES Lecture_Notes_Unit4_chapter11_sequence
SEQUNCES  Lecture_Notes_Unit4_chapter11_sequenceSEQUNCES  Lecture_Notes_Unit4_chapter11_sequence
SEQUNCES Lecture_Notes_Unit4_chapter11_sequence
Murugan Solaiyappan
 
11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx
11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx
11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx
mansk2
 
NAEYC Code of Ethical Conduct Resource Book
NAEYC Code of Ethical Conduct Resource BookNAEYC Code of Ethical Conduct Resource Book
NAEYC Code of Ethical Conduct Resource Book
lakitawilson
 

Recently uploaded (20)

"DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ...
"DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ..."DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ...
"DANH SÁCH THÍ SINH XÉT TUYỂN SỚM ĐỦ ĐIỀU KIỆN TRÚNG TUYỂN ĐẠI HỌC CHÍNH QUY ...
 
Kesadaran_Berbangsa_dan_Bernegara_Nasion.pptx
Kesadaran_Berbangsa_dan_Bernegara_Nasion.pptxKesadaran_Berbangsa_dan_Bernegara_Nasion.pptx
Kesadaran_Berbangsa_dan_Bernegara_Nasion.pptx
 
Node JS Interview Question PDF By ScholarHat
Node JS Interview Question PDF By ScholarHatNode JS Interview Question PDF By ScholarHat
Node JS Interview Question PDF By ScholarHat
 
The Cruelty of Animal Testing in the Industry.pdf
The Cruelty of Animal Testing in the Industry.pdfThe Cruelty of Animal Testing in the Industry.pdf
The Cruelty of Animal Testing in the Industry.pdf
 
C# Interview Questions PDF By ScholarHat.pdf
C# Interview Questions PDF By ScholarHat.pdfC# Interview Questions PDF By ScholarHat.pdf
C# Interview Questions PDF By ScholarHat.pdf
 
Allopathic M1 Srudent Orientation Powerpoint
Allopathic M1 Srudent Orientation PowerpointAllopathic M1 Srudent Orientation Powerpoint
Allopathic M1 Srudent Orientation Powerpoint
 
DepEd School Calendar 2024-2025 DO_s2024_008
DepEd School Calendar 2024-2025 DO_s2024_008DepEd School Calendar 2024-2025 DO_s2024_008
DepEd School Calendar 2024-2025 DO_s2024_008
 
How to Manage Large Scrollbar in Odoo 17 POS
How to Manage Large Scrollbar in Odoo 17 POSHow to Manage Large Scrollbar in Odoo 17 POS
How to Manage Large Scrollbar in Odoo 17 POS
 
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...
BÀI TẬP BỔ TRỢ 4 KỸ NĂNG TIẾNG ANH LỚP 12 - GLOBAL SUCCESS - FORM MỚI 2025 - ...
 
What is Rescue Session in Odoo 17 POS - Odoo 17 Slides
What is Rescue Session in Odoo 17 POS - Odoo 17 SlidesWhat is Rescue Session in Odoo 17 POS - Odoo 17 Slides
What is Rescue Session in Odoo 17 POS - Odoo 17 Slides
 
JavaScript Interview Questions PDF By ScholarHat
JavaScript Interview  Questions PDF By ScholarHatJavaScript Interview  Questions PDF By ScholarHat
JavaScript Interview Questions PDF By ScholarHat
 
MVC Interview Questions PDF By ScholarHat
MVC Interview Questions PDF By ScholarHatMVC Interview Questions PDF By ScholarHat
MVC Interview Questions PDF By ScholarHat
 
E-learning Odoo 17 New features - Odoo 17 Slides
E-learning Odoo 17  New features - Odoo 17 SlidesE-learning Odoo 17  New features - Odoo 17 Slides
E-learning Odoo 17 New features - Odoo 17 Slides
 
1. Importance_of_reducing_postharvest_loss.pptx
1. Importance_of_reducing_postharvest_loss.pptx1. Importance_of_reducing_postharvest_loss.pptx
1. Importance_of_reducing_postharvest_loss.pptx
 
2 Post harvest Physiology of Horticulture produce.pptx
2 Post harvest Physiology of Horticulture  produce.pptx2 Post harvest Physiology of Horticulture  produce.pptx
2 Post harvest Physiology of Horticulture produce.pptx
 
Genetics Teaching Plan: Dr.Kshirsagar R.V.
Genetics Teaching Plan: Dr.Kshirsagar R.V.Genetics Teaching Plan: Dr.Kshirsagar R.V.
Genetics Teaching Plan: Dr.Kshirsagar R.V.
 
Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)
Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)
Cómo crear video-tutoriales con ScreenPal (2 de julio de 2024)
 
SEQUNCES Lecture_Notes_Unit4_chapter11_sequence
SEQUNCES  Lecture_Notes_Unit4_chapter11_sequenceSEQUNCES  Lecture_Notes_Unit4_chapter11_sequence
SEQUNCES Lecture_Notes_Unit4_chapter11_sequence
 
11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx
11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx
11EHS Term 3 Week 1 Unit 1 Review: Feedback and improvementpptx
 
NAEYC Code of Ethical Conduct Resource Book
NAEYC Code of Ethical Conduct Resource BookNAEYC Code of Ethical Conduct Resource Book
NAEYC Code of Ethical Conduct Resource Book
 

Vu Semantic Web Meeting 20091123

  • 1. Nifty Features of OWL 2(Or, yes I was on the OWLWG)Rinke Hoekstra
  • 2. Why this topic?(… someone asked me …)Take home message“Sure, not everything about OWL 2 is great, but it does add some very nice new features that we can all use and learn to love”
  • 3. Playing The Devil’s AdvocateWhere’s the Web in OWL? Where’s the Ontology in OWL?“OL” or “WL”OWL DL and OWL Full“OWLDLED”“OWL is a description logic”OWL and Rules“Rules are just more intuitive”“People think in rules”OWL and Philosophy“OWL is philosophically flawed”OWL 2 DL and reasoning“Decidability is hugely overrated”“Consistency does not exist on the web”“OWL reasoners even die on very small knowledge bases”“I only need part of OWL, so why implement a fully OWL compliant reasoner”Expressiveness“OWL is not expressive enough for my needs”“OWL is way too expressive, no-one will ever need that”“The only useful addition of OWL to RDF is owl:sameAs”
  • 4. DISCLAIMERDo not be confused by OWL 2 (or any other W3C standard)In the end, every standard is a compromise;the result of a `political’ debate between different communities, and not technical insight.Compatible revisions of existing standards inherit political issues, misconceptions, and then add some of their ownIt’s just that if the communities are technical, you end up with a `technical’ standard.
  • 5. DISCLAIMER For OWL 2 this means:Replaces OWL 1, but is compatibleSpecies inheritance, includingOWL DL vs. OWL Full debateCompatibility with other W3C standardsSocial ‘issues’ with WG:Over-representation of DL communityUnder-representation of RDF/SW community
  • 6. Economics of OWL 2Technology pushAdvancements in Description Logics researchMarket pullExperiencesAdded expressivenessOther syntaxesBetter (‘easier’) tool developmentCaters for several communitiesHC, LS, KR, SW, Engineering, Enterprise Systems
  • 7. BackgroundOWLED workshops (60-70 people)First one in 2005Users, industry, researchW3C Member submission: OWL 1.1December 2006, following vote at OWLED 2006OWL Working GroupNovember 2007, following vote at OWLED 2007OWL 2 RecommendationOctober 2009
  • 10. After
  • 11. Back on topic…Language DesignProfilesExchange SyntaxesNifty FeaturesDatatypecoolnessProperties & RestrictionsSyntactic SugarPunningAnnotationsBonus material
  • 12. Language Design (1)OWL 1: Abstract SyntaxFrame-basedDL: axioms, Full: rules… then why frames?Hard to use for defining semanticsto parseto extend“an OWL ontology is an RDF graph”OWL 2: Structural SpecificationAxiom centredUML/MOF data model“an OWL 2 ontology is an instance O of the Ontology UML class”“any OWL 2 ontology can also be viewed as an RDF graph”OWL 2: Functional Style Syntax BNF grammarhttp://www.w3.org/TR/owl2-syntax/
  • 13. Language Design (2)OWL 1: SpeciesLite, DL, FullConfusion between semantics and syntaxOWL Lite? Nah…OWL 2: SemanticsDirect Semantics (DL), http://www.w3.org/TR/owl-direct-semanticsRDF-Based Semantics (Full), http://www.w3.org/TR/owl-rdf-based-semanticsMost OWL 2 DL ontologies are OWL 1 Full
  • 14. ProfilesOWLs living in the swamps of AmsterdamOWL 2 EL Polynomial time algorithms for standard reasoning tasks; Large ontologies (TBox)OWL 2 QL Conjunctive query answering in in LogSpace using RDB technology;Lightweight ontologies that organize many individualsAccess the data directly via relational queries (e.g., SQL). OWL 2 RL(a.k.a. RDFS 3.0 ?)Polynomial time algorithms using rule-extended DB technologiesLightweight ontologies that organize many individualsOperate directly on RDF triplesRule set provided by specificationSemantics follows from syntactic restrictionsExtra “global restrictions” for OWL 2 DL, QL and ELExtensible!
  • 15. Exchange SyntaxesOWL 1: RDF/XML (2004)W3C Note: OWL XML Syntax (2003)OWL 2: RDF/XML (mandatory)TurtleFunctional Style SyntaxOWL XML (2009) (+ mandatory GRDDL transformation)Manchester Syntax
  • 16. Hey, show me those nifty features already!Yeah yeah…
  • 17. Datatypes (1)Extended XML Schema compatibilityNew datatypes not in XML Schemaowl:real, owl:rationalDatatype definitionsxsd:minInclusive, xsd:maxInclusive, xsd:minExclusive, xsd:maxExclusivexsd:pattern (e.g. regular expressions), xsd:lengthrdf:PlainLiteral(together with RIFWG)All RDF plain literalsNot to be used in syntaxes that already deal with RDF plain literalsDatatypeDefinition(  a:SSN    DatatypeRestriction(xsd:stringxsd:pattern "[0-9]{3}-[0-9]{2}-[0-9]{4}" ))
  • 18. Datatypes(2)Datatype DefinitionsData Range CombinationsKeysOnly hold for named individualsDatatypeDefinition( :adultAgeDatatypeRestriction(xsd:integerminInclusive 18)DataComplementOf( :adultAge)DataUnionOf( :adultAge :studentAge)…HasKey( :Transplantation :donorId :recipientId :ofOrgan)
  • 19. Datatypes (3)N-arydatatypesExtension (Working Group Note)http://www.w3.org/TR/owl2-dr-linear/Linear equationsDataAllValuesFrom ( :meltingPoint :boilingPointDataComparison(Arguments(xy) leq( xy ))))
  • 20. Properties (1)Property TypesAsymmetric propertiesReflexive and Irreflexive propertiesTop and bottom propertiesProperty chainsSubObjectPropertyOf( ObjectPropertyChain( a:hasMothera:hasSister ) a:hasAunt)
  • 21. Properties (2)Property AssertionsDisjointnessProperty restrictionsSelf Restriction (local reflexivity)Qualified Cardinality RestrictionsDatatype restrictions‘ObjectInverseOf’ in restrictionsObjectHasSelf( a:likes )DataSomeValuesFrom( a:hasAgeDatatypeRestriction( xsd:integerxsd:minInclusive “13”^^xsd:integer xsd:maxExclusive “20”^^xsd:integer ) )
  • 22. Just an illustration (three, actually)SubObjectPropertyOf( ObjectPropertyChain ( a:isElephantowl:TopObjectPropertya:isMouse ) a:likes )
  • 23. Syntactic SugarDisjoint UnionDisjoint ClassesNegative property assertionsDisjointUnion(:BrainHemisphere :LeftHemisphere :RightHemisphere)DisjointClasses( :LeftLung :RightLung)NegativeDataPropertyAssertion( :hasAge :Frank 50^^xsd:integer )EquivalentClasses ( ObjectOneOf( :Frank ) ObjectComplementOf ( DataHasValue( :hasAge 50^^xsd:integer )) )
  • 24. Punning (wordplay)Any name can be used for any type of entityDirect SemanticsInterpreted as separate entitiesRDF-Based SemanticsInterpreted as the same entity… but no punning between:Datatype and Class namesData-, Object- and Annotation property names(actually supported by most implementations)ConsequenceStrongly typed syntax (FS, OWLXML)…but not in RDF graphs
  • 25. AnnotationsNo semantics in Direct SemanticsSupported on all entitiesClasses, individuals, propertiesAxioms, annotations, ontologiesAnnotation axiomsAnnotation SubpropertiesDomain and RangeAnnotationAssertion (skos:prefLabel :SWMeeting “Semantic Web Meeting”@en )SubClassOf( Annotation( rdfs:comment ”Every SWMeeting is a Meeting.") :SWMeeting :Meeting)
  • 26. Imports & VersioningImport by location… but comes down to ‘just’ dereferencingOntologyIRI and VersionIRIOntologies should be accessible atOntologyIRIIf no VersionIRI supplied or if it is the latest versionVersionIRIIf a VersionIRI is suppliedImport statement may point to either
  • 27. Other things…Internationalized Resource IdentifiersBNodes are existentialsGlobal restrictions for Direct SemanticsAnonymous individuals are BNodes… no change in RDFDeclarationsIndicate what ontology defines an entity… but mostly just nice for parsers, no change in RDFObjectPropertyAssertion(<http://example.org/p> <http://example.org/a> _:http://example.org/#genid-x)ClassAssertion(ObjectSomeValuesFrom(<http://example.org/p> owl:Thing) <http://example.org/a>)
  • 28. Bonus MaterialPretty decent outreach materialComprehensive OWL 2 Overviewhttp://www.w3.org/TR/owl-overview/OWL 2 Quick Reference Cardhttp://www.w3.org/TR/owl-quick-reference/OWL 2 Primerhttp://www.w3.org/TR/owl-primer/OWL 2 New Features and Rationalehttp://www.w3.org/TR/owl-new-features/OWL 2 Conformancehttp://www.w3.org/TR/owl-conformance
  • 29. What I like about OWL 2Cleaner language designAdded expressivenessPropertiesDatatypesIncreased compatibility between Full and DLPunningAnnotation propertiesProfiles… most notably OWL 2 RL … hooks for extensibility