UML allows the cardinality of a property to be left unspecified, which is interpreted in UML as a minimum of one and a maximum of one. Properties in an OWL ontology are defined with unspecified cardinalities, but unlike UML, the concept modelling profile interprets the cardinalities of such properties as being zero to many (“0..*”). Thus, if you import an ontology, the cardinalities will be “0..*” by default.
Imported Multiplicities
Importing intersected cardinality restrictions on the same property now results in the cardinalities being applied to the same UML property. The figure below shines a better light on the subject.
The modeling tool now imports and transforms multiple multiplicities to the same class into a single multiplicity.
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