Applied Semantic Web Technologies

36  ◾  Rajendra Akerkar

an ontology to answer its competence questions. Bridge rules specify associations

among elements of two or more ontologies, for example:

Bridge Rule :

:

:

< >

< >

Oi Fi

Ok Fj

e schema reads: If Fi is a true formula within ontology Oi, then Fj is true in the

ontology Ok. Bridge rules support reasoning across ontologies. Embedding produc-

tion rules have been addressed at the symbolic level too. In a hybrid approach, a

separation is maintained between the predicates used in the ontologies and those

in the rules. In a homogeneous approach, both ontologies and rules are represented

with the same language.

2.8 Ontology Languages ...