Geoscience Reference
In-Depth Information
formalizing in
OWL
2
- the Ontology Web Language - the content of
databases specifications.
The objective of the system described in this paper is precisely to
capitalize on the ontologies developed in the
GéOnto
project framework,
and to combine them with the latest web technologies in the field of
dissemination of spatial data, via an application allowing a user to
discover, in a simple way, databases which are the most appropriate to
his/her needs. The purpose of this system is to provide, through a user-
friendly interface, complex information on geographic data, previously not
accessible or only accessible by reading the complex specification files.
More precisely, the goals of our system are the followings:
•
Guiding the user in specifying which information is of interest for
her/him with terms from the domain ontology (e.g. river), rather than
technical terms used in the database schema (e.g. '
hydrographic section
'
or even '
hydr_lin
').
•
Retrieving in the database data corresponding to the user's need.
•
Providing additional information about the data: which real world
entities are represented (e.g. all the watercourses or only those with
permanent flow); how they are represented in the database (in which
class, with which attribute values?); and how are they distinguished
from other entities (e.g. does the information in the database allow to
make the distinction between man-made canal and natural
watercourses?).
•
Visualizing the data corresponding to the user's need using web
mapping techniques.
Several ontology-based systems have already been proposed for geodata
discovery and retrieval (Paul and Ghosh 2006), (Nambiar et al. 2006),
(Lutz and Klien 2006), (Klien 2008). However, none of them used
specifications-based semantic annotation of geodata to provide users with
detailed information about data semantics. If some user is looking for data
about forests, our systems will not only explain that forests are represented
in the '
Wooded area
' feature class, but also that the wooded area
2
http://www.w3.org/TR/owl-features/
