Geoscience Reference
In-Depth Information
straightforward way by applying the following translation scheme (some UML
constructs may be hard to represent in OWL, but they don't appear in this model):
• UML class or association class
→
OWL class
• UML simple association
→
OWL object property (
+
some
,
only
,
min
, or
max
constructs to represent number constraints)
• UML attribute (integer, string, boolean valued)
→
OWL datatype property
• UML subclasses
→
OWL
subClassOf
axioms.
This translation provides the basic vocabulary that will be used to represent the
visualization techniques.
An interesting feature of the OWL language is its ability to define new classes
by combining already defined classes through logical operators. Therefore, the
description element mentioned in point 1 here above (“techniques with an output
location that is a Street or a Building but not a WaterBody”) can be represented as:
VisualizationTechnique
and
(outputLocation
some
(ObjectAttached
and
objectType
some
(Street
or
Building)
and
(
not
WaterBody)))
4.2 Formal Representation of 3D Information Visualization
Techniques
A technique is represented as an instance of the
VisualizationTechnique
class,
linked to instances of the
DataDescription
,
OutputLocation
and
OutputShape
classes that describe its characteristics.
The following expression describes a technique, illustrated on Fig.
8
, that pre-
sents texts relative to buildings as text panels located on a street.
VisualizationTechnique
and
(outputlocation
some (ObjectAttached and
objectType
some
Street))
and
(outputshape
some
RichTextRepresentation)
and
(datadescription
some
(DataDescription
and
(coverage
some
Building)
and
(datatype
some
RichTextType)))
Similarly, Fig.
9
shows a technique that uses cones of different heights positioned
on streets or squares to represent the number of pedestrians passing at different
locations. Its formalized description can be:
VisualizationTechnique
and
(outputlocation
some (ObjectAttached
and objectType
some
Transportation
Area))
and
(outputshape
some
Cone)
and
(datadescription some(DataDescription
and
(coverage
some
Surface)
