42
J. R. Prasad et al.
Fig. 1 Hierarchies in
vehicle domain
Vehicle
Manual transmission
Vehicle
Auto transmission
Vehicle
Two Wheeler
Four Wheeler
Gruber’s and refined by R. Studer: An ontology is an explicit and formal specification of a conceptualization. Throughout ontology there is a finite number of terms
and the relationships between certain terms. Essential domain concepts (classes of
objects) are demonstrated by terms. for example, in a vehicle domain vehicle, manual
transmission vehicle, auto transmission vehicle, two-wheeler, four-wheeler, engine,
wheels, driver, passenger, license etc. are concepts. These classes are related to each
other by hierarchical relationship. In vehicle domain two-wheeler, four wheelers are
subclasses of vehicle as all the properties of vehicle are present in two-wheeler and
four wheelers. Subclass has all the properties of super class plus it may have its
own specific properties. Other than hierarchical relationship, ontologies may have
extra information about properties, disjoint or overlapped concepts, any restrictions
or constraints and other logical relationships (Fig. 1).
Ontologies seems to be very useful in supporting the semantic interoperability.
Ontologies are helpful for the organization as well as navigation of the web sites.
Generally, web pages provide menu, in terms of hierarchies. Use clicks on it go
navigate through it. Moreover, accuracy of web searches can be improved with the
help of ontology. The search engine can filter out and display the pages based on
precise ontology term within less time. Hierarchical relationships between terms of
ontology can be exploited by the web engine in order to accomplish the web search.
E.g. in case specific term related searches are not available, engine can display results
of more general term in hierarchy.
3.3 RDF
Resource Description Framework is a system to describe resources. RDF’s basic
concepts are resources, properties, and statements. RDF has very simple yet elegant
data model. Data model consists of resources connected to each other via properties.
According to RDF, anything is resource which can be distinguished by Uniform
J. R. Prasad et al.
Fig. 1 Hierarchies in
vehicle domain
Vehicle
Manual transmission
Vehicle
Auto transmission
Vehicle
Two Wheeler
Four Wheeler
Gruber’s and refined by R. Studer: An ontology is an explicit and formal specification of a conceptualization. Throughout ontology there is a finite number of terms
and the relationships between certain terms. Essential domain concepts (classes of
objects) are demonstrated by terms. for example, in a vehicle domain vehicle, manual
transmission vehicle, auto transmission vehicle, two-wheeler, four-wheeler, engine,
wheels, driver, passenger, license etc. are concepts. These classes are related to each
other by hierarchical relationship. In vehicle domain two-wheeler, four wheelers are
subclasses of vehicle as all the properties of vehicle are present in two-wheeler and
four wheelers. Subclass has all the properties of super class plus it may have its
own specific properties. Other than hierarchical relationship, ontologies may have
extra information about properties, disjoint or overlapped concepts, any restrictions
or constraints and other logical relationships (Fig. 1).
Ontologies seems to be very useful in supporting the semantic interoperability.
Ontologies are helpful for the organization as well as navigation of the web sites.
Generally, web pages provide menu, in terms of hierarchies. Use clicks on it go
navigate through it. Moreover, accuracy of web searches can be improved with the
help of ontology. The search engine can filter out and display the pages based on
precise ontology term within less time. Hierarchical relationships between terms of
ontology can be exploited by the web engine in order to accomplish the web search.
E.g. in case specific term related searches are not available, engine can display results
of more general term in hierarchy.
3.3 RDF
Resource Description Framework is a system to describe resources. RDF’s basic
concepts are resources, properties, and statements. RDF has very simple yet elegant
data model. Data model consists of resources connected to each other via properties.
According to RDF, anything is resource which can be distinguished by Uniform