- From: Luke Steller <Luke.Steller@infotech.monash.edu.au>
- Date: Thu, 17 Aug 2006 20:52:39 +1000
- To: public-owl-dev@w3.org
Hello All, I have the following ontology about colors and printers. I have defined colours: Red, Yellow, Blue and Black - all different from each other. For the 'hasColor' property, I have classes specified as cardinality exactly 4 (HasFourColours), at least 4 (HasAtLeastFourColours), exactly 0 (HasNoColors). I have defined an instance/individual of Printer with all four colours and another second printer with not 'hasColor' property instances specified. I would have thought that printer1 should be an instance of both 'HasFourColors' and 'HasAtLeastFourColors', but it is only an instance of 'HasAtLeastFourColors', when using pellet for reasoning. Also printer2 I would have thought would be an instance of 'HasNoColors' but its not. Can anyone help me understand why this is so? How would one create a class which refers to those printers with no colours and exactly 4 colours? Also why does printer1 fail to be an instance of 'HasAtLeastFourColours' when the colours are not specified as 'differentFrom' one another, is this because there is no unique name assumption, therefore it doesnt know if these are really different? Thanks, Luke PhD Candidate Faculty of Information Technology Monash University A U S T R A L I A ============================= <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:test="urn:test:" xmlns:xsd="http://www.w3.org/2001/XMLSchema#" xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#" xmlns:owl="http://www.w3.org/2002/07/owl#" xmlns:daml="http://www.daml.org/2001/03/daml+oil#" xmlns:dc="http://purl.org/dc/elements/1.1/"> <owl:Ontology rdf:about=""/> <owl:Class rdf:about="urn:test:Printer"/> <owl:Class rdf:about="urn:test:hasAtLeastFourColours"> <owl:equivalentClass> <owl:Restriction> <owl:onProperty> <owl:ObjectProperty rdf:about="urn:test:hasColor"/> </owl:onProperty> <owl:minCardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger" >4</owl:minCardinality> </owl:Restriction> </owl:equivalentClass> </owl:Class> <owl:Class rdf:about="urn:test:hasNoColour"> <owl:equivalentClass> <owl:Restriction> <owl:onProperty> <owl:ObjectProperty rdf:about="urn:test:hasColor"/> </owl:onProperty> <owl:cardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger" >0</owl:cardinality> </owl:Restriction> </owl:equivalentClass> </owl:Class> <owl:Class rdf:about="urn:test:HasFourColors"> <owl:equivalentClass> <owl:Restriction> <owl:onProperty> <owl:ObjectProperty rdf:about="urn:test:hasColor"/> </owl:onProperty> <owl:cardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#nonNegativeInteger" >4</owl:cardinality> </owl:Restriction> </owl:equivalentClass> </owl:Class> <owl:Class rdf:about="urn:test:Color"/> <owl:ObjectProperty rdf:about="urn:test:hasColor"> <rdfs:range rdf:resource="urn:test:Color"/> </owl:ObjectProperty> <test:Color rdf:about="urn:test:yellow"> <owl:differentFrom rdf:resource="urn:test:blue"/> <owl:differentFrom rdf:resource="urn:test:black"/> <owl:differentFrom rdf:resource="urn:test:red"/> </test:Color> <test:Color rdf:about="urn:test:blue"> <owl:differentFrom rdf:resource="urn:test:yellow"/> <owl:differentFrom rdf:resource="urn:test:black"/> <owl:differentFrom rdf:resource="urn:test:red"/> </test:Color> <test:Color rdf:about="urn:test:black"> <owl:differentFrom rdf:resource="urn:test:yellow"/> <owl:differentFrom rdf:resource="urn:test:blue"/> <owl:differentFrom rdf:resource="urn:test:red"/> </test:Color> <test:Color rdf:about="urn:test:red"> <owl:differentFrom rdf:resource="urn:test:yellow"/> <owl:differentFrom rdf:resource="urn:test:blue"/> <owl:differentFrom rdf:resource="urn:test:black"/> </test:Color> <test:Printer rdf:about="urn:test:printer1"> <test:hasColor rdf:resource="urn:test:black"/> <test:hasColor rdf:resource="urn:test:red"/> <test:hasColor rdf:resource="urn:test:blue"/> <test:hasColor rdf:resource="urn:test:yellow"/> </test:Printer> <test:Printer rdf:about="urn:test:printer2"/> </rdf:RDF>
Received on Thursday, 17 August 2006 10:52:54 UTC