Ontology itself is a formal representation of knowledge
widely used to aid electronic data processing. Common examples
include cyc [3], and those in biological and medical
areas like gene ontology [4] and foundational model
of anatomy [5]. Ontology uses a set of tuples to describe
some knowledge in a certain domain and these tuples are
easily processed by computers. With the help of recent
markup ontology languages like OWL/RDF, ontology has
become more friendly for human understanding than traditional
ones like CycL [6]. Meanwhile, as ontology defines
all necessary concepts (classes) and their relations in