19 Dec revd CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 1 OWL Lite: Ch. 14- Deriving Classes Ch. 15- Individuals Atilla ELÇİ

19 Dec Rev CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 2 OWL Lite: Deriving New Classes Simple named subclass (rdfs:subClassOf property): –Specialization of another class –rdfs:subClassOf is a transitive property. Class equivalency (owl:equivalentClass property): –Identifies two synonymous classes

30 Dec. 2008CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 3 OWL Lite: Deriving New Classes (continued) Intersection (owl:intersectionOf property): –A class composed of members common to all extensions.

19 Dec Rev CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 4 OWL Lite: Describing Individuals Indiviuals are: –instances (members) of user-defined ontological classes (Tbox). –instantiated with RDF statements and encoded using RDF/XML –instance identifier is declared using rdf:ID attribute –rdf:type or typedNode syntax is used to associate with a class –individual identifier is a URIref –referenced using rdf:about or rdf:resource –individuals are collected in an instance or artifact file (ie, Abox). As an RDF/XML file, it has header, body, and footer just like an ontology file. Contrast class vs subclass, individual vs instance: –As in OO, mostly. –But, check Tracy §15.1

19 Dec Rev CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 5 OWL Lite: Individuals Instantiating using RDF Descriptions: Instantiating using class name: Describing individuals while instantiating: –Insert attribute statement into the inner text Describing existing individuals: Ali Veli

19 Dec Rev CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 6 Individuals: relating them Equivalent individuals (owl:sameAs): –Means that two URIs refer to the same individual; used while declaring or describing an instance: –Usually used to “join” different ontology files. Differentiating individuals (owl:differentFrom): –Identifies pairwise distinct instances: –Supports inferencing

CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 7 Individuals: relating them (continued) Differentiating Groups of individuals (owl:AllDifferent class + owl:distinctMembers property): –Shortcut declaration instead of many owl:differentFrom statements.

19 Dec revd CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 8 Individuals (continued) Ref. Fig Summary of constructs describing individuals

19 Dec revd CmpE 583 Fall 2006 OWL Lite- Classes & Individuals. 9 OWL Lite: Summary Fig Imports & Namespace Dependency Relationships Fig Header Concepts Fig OWL Lite Classes & Properties Fig Local Restriction Types Fig Property Characteristics Taxonomy Fig Constructs for Describing Individuals Fig OWL Concept Type Separation Taxonomy –NB: starred items are disjoint in OWL Lite. Table OWL Lite Constructs Table OWL Lite Restriction Summary