A Proposal for Addressing Issues Related to RDF Mapping

2/7 Outline Disallow punning between object and data properties Require that each URI used as a property must be explicitly typed as either an object or a data property Modify all the related deliverables RDF mapping map declarations/typing axioms into rdf:type get rid of duplicate vocabulary XML syntax functional-style syntax

3/7 Changes to Structural Specification Move the discussion about declarations/typing axioms into the core part of the spec Allow all entities to be declared solves the I want to put a class into an ontology problem Typing axioms are mandatory if there is ambiguity object vs. data property class vs. datatype If a URI u is used as an object property in an ontology O then the import closure of O… …must contain a declaration saying that u is an object property …must not contain a declaration saying that u is a data or an annotation property The situation is analogous for data and annotation properties

4/7 Changes to Functional-Style Syntax Current: objectPropertyURI := URI objectPropertyExpression := objectPropertyURI | … objectSomeValuesFrom := 'ObjectSomeValuesFrom' '( objectPropertyExpression description ') Proposed: objectPropertyURI := URI [OP] objectPropertyExpression := objectPropertyURI | … objectSomeValuesFrom := 'SomeValuesFrom' '(' objectPropertyExpression description ') Recommend: put all property typing statements at the top of the file Means that the import closure of the ontology declares URI as an object property

5/7 Changes to RDF Mapping Map declarations into rdf:type e.g., a declaration that u is an object property is mapped into Get rid of duplicate vocabulary solves the problem of nonmonotonocity of the mapping State that, in the reverse transformation, only explicit rdf:type triples count as declarations the triples implied by the RDFS semantics can be used for repair, but, strictly speaking, do not constitute declarations Recommend: put all property typing statements at the top of the file

6/7 RDF Mapping – Example OWL 1.1 FS ontology: Declare(OWLClass(A)) Declare(OWLClass(B)) SubClassOf( A B ) The RDF mapping will be: Currently, you also got the following triples, but this will go away

7/7 Changes to XML Syntax Similar to changes in the functional-style syntax drop ObjectSomeValuesFrom in favour of SomeValuesFrom