Military Communications and Information Technology: A Trusted ...

Chapter 3: Information Technology for Interoperability and Decision...
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IEO has the form of hierarchical descriptions of the domain of knowledge about
traffic monitored by INSIGMA subsystem. The main class of the ontology model
is InsigmaEvent. Together with its subclasses it describes road and weather
events (see Fig. 3). Each class in the ontology has its own description expressed by
using relations, attributes and restrictions which allows to create complex definitions
of particular domain of knowledge
Developed for the purpose of INSIGMA the event domain model includes
formal model in Ontology Web Language (OWL) and rules created in Semantic
Web Rule Language (SWRL).
The formal ontology model consists of:
• taxonomy of classes which describes concepts (T-Box) (see Fig. 3),
• relations describe relationships between classes and instances (see Fig. 4),
• individuals which are instances, specific objects of classes (A-Box),
• attributes describe properties or parameters that classes or its instances
can have,
• restrictions – formally stated descriptions of what must be true in order
for some assertion to be accepted as input,
• axioms – assertions (including rules) in a logical form that together comprise
the overall theory that the ontology describes in its domain of applications.
Figure 3. Taxonomy of INSIGMA Event Ontology
Rules are statements in the form of if-then (antecedent-consequent) sentences
that describe the logical inferences that can be drawn from an assertion in a particular
form.