Linking Guide Linking RDF(/RDFS/OWL2) Data Sets Michel Bhms 2 February 05, 2015 Michel Bhms Linking Guide 5 Star Linked Data concept (assuming digital, no paper) LINKING GUIDE MODELLING GUIDE LINKED WITH OTHERS LINKED & INFERRED W3C STANDARDS (HTTP, URI, RDF, RDFS, OWL2, SKOS, TURTLE, SPARQL, TRIG, LDP) OPEN STANDARDS
(EXPRESS, SPFF, CSV, XSD, XML) MACHINE PROCESSABLE (EXCEL, R(E)V(I)T) AVAILABLE IN THE CLOUD (POTENTIALLY LIMITED BY SECURITY MODEL) 3 April 08, 2015 Michel Bhms Linking Guide Basic Assumptions A Linking is a set of one or more Links relating two RDF(/RDFS/OWL2) data sets (ontologies and/or their sets of individuals) bi-directionally These Linkings are just like data sets to be mapped, data sets themselves, fully described using a subset of RDF/RDFS/OWL2 following the same V-Con Modelling Guide Not bound to a particular software tool (i.e. Relatics) or particular semantics/format (i.e. like MS Excel file format) making full use of interoperable and well-defined RDF/RDFS/OWL2 semantics and Turtle syntax (i.e. also
) Enabling inferred data from asserted data via standard reasoners (instead of dedicated transformation software tools) 4 April 08, 2015 Michel Bhms Linking Guide Four Relevant dimensions 1. Three key Meta concepts: Classes (owl:Class) Properties (owl:DatatypeProperty & owl:ObjectProperty) Individuals (owl:NamedIndividual) 2. 12 Venn situations 5 for classes, same 5 for properties, 2 other for individuals 3. Three Semantic levels (for classes) 4. Asserted versus Inferred data 5 February 05, 2015
Michel Bhms Linking Guide Assume 2 ontologies: x and y x, y are prefixes for name space URIs asserted or inferred 1 Class A in ontology x, x:A 1 Class B in ontology y, y:B 1 Property in ontology x: x:c 1 Property in ontology y: y:d 1 Individual in ontology x: x:a 1 Individual in ontology y: y:b 6 February 05, 2015 Michel Bhms Linking Guide 5 Venn situations for classes 1.
2. AND 3. x:A owl:EquivalentClass y:B The default, unconstrained. Independent classes, no mapping rule relevant
 rdf:type owl:AllDisjointClasses ; owl:members ( x:A y:B ) . No mapping rule relevant (only for negative data) 7 February 05, 2015 Michel Bhms Linking Guide 5 Venn situations for properties 1. 2.
x:c rdfs:subPropertyOf y:d y:d rdfs:subPropertyOf x:c 2. AND 3. Same as: x:A owl:EquivalentProperty y:B 4.
The default, unconstrained. Independent properties, no mapping rule 3. 5.
x:c owl:propertyDisjointWith y:d No mapping rule relevant (only for negative data) 8 February 05, 2015 Michel Bhms Linking Guide 2 Venn situations for individuals 1. x:a owl:sameAs y:b 2.
x:a rdf:type y:B 9 February 05, 2015 Michel Bhms Linking Guide Link Types (#6) Class level x:A rdfs:subClassOf y:B (== y:B rdfs:subClassOf x:A)
x:A owl:EquivalentClass y:B (syntactic sugar really) x:c rdfs:subPropertyOf y:d (==y:d rdfs:subPropertyOf x:c) x:A owl:EquivalentProperty y:B (syntactic sugar really) Individual or individual<>class level x:a owl:sameAs y:b x:a rdf:type y:B Issue: More link types via restrictions? Restrictions at classes involving other ontologies (minCard/maxCard/Card/someValuesFrom/AllValuesFrom/hasValue) Restrictions at properties involving other ontologies (domain/range) 10 February 05, 2015 Michel Bhms Linking Guide
3 semantic levels for classes L1: Classes without restrictions L2: Classes with only necessary Restrictions L3: Classes with necessary & sufficient (n&s) Restrictions A data set (now ontology) can have a mix of 1/2/3 An ontology can be semantically strong, having only level 3 classes 11 February 05, 2015 Michel Bhms Linking Guide Inference potential Depending on the semantic level of the classes more or less can be inferred from asserted data Standard OWL2 inferences (entailments regimes) like: If (x:a rdf:type x:A AND x:A rdfs:subClassOf y:B) THEN (x:a rdf:type y:B) 12 February 05, 2015 Michel Bhms
Linking Guide Example x is some context ontology, y some common ontology following the VCon Modelling Guide Ontology x asserts: x:RedCar rdf:type owl:Class x:colour rdf:type owl:DatatypeProperty x:colour rdfs:range xsd:string x:MyRedCar rdf:type x:RedCar x:MyRedCar x:colour Red^^xsd:string Ontology y asserts y:Car rdf:type owl:Class y:colour rdf:type owl:DatatypeProperty (note not the same as x:colour!) 13 February 05, 2015 Michel Bhms Linking Guide Venn situation here Clearly the intended meaning of the mapping rules is: x:RedCar rdfs:subClassOf y:Car
x:colour owl:EquivalentProperty y:colour 14 February 05, 2015 Michel Bhms Linking Guide Semantic Level here (L1) x:RedCar and y:Car have no n&s restrictions Also both have no explicit restrictions at all: so we did not specify for instance that a RedCar has the value red for x:colour explicitly Note we could have never inferred x:MyRedCar rdf:type x:RedCar based on x:MyRedCar x:colour red^^xsd:string) i.e. No way to automatically classify So we have to assert (as we did) x:MyRedCar rdf:type x:RedCar Note we also cannot infer in any way that x:RedCar is a subclass of y:Car i.e. No way to automatically subclass So we have to assert x:RedCar rdfs:subClassOf y:Car as mapping rule
Doing that we CAN infer: x:MyRedCar rdf:type y:Car X:MyRedCar y:colour red^^xsd:string And if we assert extra: y:MyCar rdf:type y:Car AND x:MyRedCar owl:sameAs y:MyCar We can extra infer: y:MyCar x:colour red^^xsd:string and y:MyCar y:colour red^^xsd:string Note that this had not been possible if he had not asserted x:MyRedCar x:colour red^^xsd:string in the first place (it would have been implicit in the RedCar class only 15 February 05, 2015 Michel Bhms Linking Guide In case semantic level 2 So: x:RedCar and y:Car have again no set of n&s restrictions but this time we add an explicit restriction on the x:RedCar class: x:RedCar a owl:Class ; rdfs:subClassOf owl:Thing ; rdfs:subClassOf [ a
owl:hasValue owl:Restriction ; "red"^^xsd:string ; owl:onProperty x:colour ]. 16 February 05, 2015 Michel Bhms Linking Guide In case semantic level 2 Again, we can never infer that x:MyRedCar is of type x:RedCar i.e. again no way to automatically classify, even if x:MyRedCar x:clour red was asserted in the first place So we again have to assert x:MyRedCar rdf:type x:RedCar Again, we also cannot infer in any way that x:RedCar is a subclass of y:Car i.e. again no way to automatically subclass So we again have to assert x:RedCar rdfs:subClassOf y:Car Now we CAN infer:
x:MyRedCar rdf:type y:Car (as before) And if we assert: y:MyCar AND x:MyRedCar owl:sameAs y:MyCar (as before) And x:MyRedCar x:colour red (because of the explicit restriction), no need to assert anymore! And even: y:MyCar x:colour red (as before) And even: y:MyCar y:colour red (as before) 17 February 05, 2015 Michel Bhms Linking Guide In case semantic level 3 Now we add for both classes n&s restrictions like: In x ontology: x:RedCar owl:equivalentClass (x:vehicleType=car and x:colour=red) In y ontology: y:Car owl:equivalentClass (y:vehicleType=car and y:colour=red In mapping ontology : x:vehicleType owl:equivalentProperty y:vehicleType AND x:colour owl:equivalentProperty y:colour
which makes it possible to Infer that x:MyRedCar rdf:type x:MyCar (automatic classification) in case x:MyRedCar x:colour red^^xsd:string was asserted, but more important: Infer that x:RedCar rdfs:subClassOf y:Car (automatic subclassing based on the n&s class restrictions on both sides) 18 February 05, 2015 Michel Bhms Linking Guide Bottom Lines In general we have to specify mapping rules explicitly for classes since strong L3 definitions are not likely We always need mapping rules for properties We need mapping rules for individuals to go beyond enrichment (and have all inferred data in both ontologies or in case such individuals are already asserted in both ontologies and actually refer to the same real world entity We need as much as necessary restrictions to make knowledge explicit on class level and to avoid the need to provide all this data on individual level (for all individuals) If this info is not explicitly at class level and not available at
individual level this info is not really there at all (only in the name of the class) so inference will obviously also not create it (more positively: no info is really lost, is was never their in the first place) 19 February 05, 2015 Michel Bhms Linking Guide Issues Other restriction types So far we discussed Restrictions of the form owl:hasValue Other types: hasRange (asphalt example) Or even (?) owl:minCardinality, owl:maxCardinality, owl:allValuesFrom, owl:someValuesFrom, . What happens now (when inferring) Role of domain/range clauses for properties Datypes and Lexical values Do we also have to indicate that x:red = y:red or a bit more abstract x:datatype is y:datatype if not the same (like xsd:string) Do we also need rule x:c owl:differentFrom y:d ? 20
February 05, 2015 Michel Bhms Linking Guide Simple CBNL Use Case /1 Ontology x (being CBNL) as entrance to ontology (and its individuals) y Where classes from y are equivalent or subclasses of classes in x (only classes since properties are also modelled as classes in CBNL) No need to move data Ontology y maybe not even an ontology, just connected via specific api/web services etc. 21 February 05, 2015 Michel Bhms Linking Guide Simple CBNL Use Case /2 2 ontologies: x (CBNL) and y (ETIM) 1 Individual in some ontology c classified as an item in CBNL: c:a rdf:type x:A (also a link from c to x) A being an object-class in CBNL
1 Class B in ontology y (ETIM), y:B In mapping rule: y:B owl:equivalentClass x:A or y:B rdfs:subClassOf x:A (being more realistic in case of specific restrictions in y) 22 February 05, 2015 Michel Bhms Linking Guide Simple CBNL Use Case /3 (flow) You can now browse from c:a to x:A and search in all mapping ontologies for y:B like classes being equivalent or subclass and known more info on class level and existing individuals for y:B (here 2BA products)
Lauren Crigler Peter Winch Anbrasi Edward Penny Dawson Cathy Wolfheim There may be fewer gaps than we think. A lot of good field work never makes it into the peer-reviewed literature. When we do it, we'll know what we don't...
Moodle is an ideal online learning solution for: "My first live class just ended and it was a tremendous success, both in the behavior of the program and the quality and longevity of my participants. Moodle has been terrific to...
Library. STUDY HABITS. ... Students no longer take AS examinations at Campion, as these have been de-coupled from A Levels (i.e. they are separate qualifications) ... Examination Board (OCR, AQA, EDEXCEL) Download specification. Scheme of Work. Methods of Assessment:
Symbolic frame: Focuses on symbols and meanings related to events. Culture is important. ... as evidenced by three well-publicized IT project failures in Australia (Sydney Water's customer relationship management system, the Royal Melbourne Institute of Technology's academic management ...
Vrednovanje ukupnog oštećenja provodi se isključivo po MKF - međunarodna klasifikacija funkcioniranja. Stupanj oštećenja tjelesnog i/ili duševnog zdravlja prema novim Tablicama. uz obveznu primjenu MKB-10 - Međunarodna klasifikacija bolesti i srodnih zdravstvenih problema .