The SEDRIS Data Representation Model
APPENDIX A - Classes
Classification Related Features
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Class Name: Classification Related Features
Subclasses
This DRM class is concrete and has no subclasses.
Definition
An instance of this DRM class specifies an aggregation of
<Feature Hierarchy>
instances organized according to their ECCs such that each
<Feature Hierarchy> component
represents:
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a different thematic layer, or
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a different classification of
<Feature Representation>
instances within a single thematic layer.
Each branch of a
<Classification Related Features>
instance therefore
has a <Classification Data> instance
associated with it as a link object,
specifying its (possibly elaborated) classification.
Primary Page in DRM Diagram:
Secondary Pages in DRM Diagram:
This class appears on only one page of the DRM class diagram.
Example
Several thematic layers of features might be grouped using a
<Classification Related Features>
instance, with each of its components
representing a separate thematic layer (such as culture or vegetation).
In such a case, the
unique_descendants and
strict_organizing_principle
flags of the
<Classification Related Features>
instance should be set to
SE_TRUE. The
<Classification Data> link object
associated with each of its components identifies the contents of each
thematic layer, and each of the components is an independent topological
complex and has a
<Feature Topology Hierarchy>
component.
A region consisting of forest and water is represented as a
<Classification Related Features>
instance with
strict_organizing_principle set
to SE_TRUE, containing two
<Union Of Features> components. The first,
containing the forest features, has a
<Classification Data>
link object with tag =
ECC_FOREST, while the second, containing the water
features, has a <Classification Data>
link object with tag =
ECC_WATER.
Considering the first example, suppose that roads run through
the forest. The forest <Union Of Features>
instance can then be replaced with another
<Classification Related Features>
instance having two branches, one representing environmental objects
classified as ECC_ROAD and the other environmental objects
classified as ECC_FOREST, and the
strict_organizing_principle
flag in the previous example's
<Classification Related Features>
instance is set to
SE_FALSE,
because the forest branch at the coarse level contains non-forest
(in this case, road) features.
A large collection of features might be organized using a
<Classification Related Features>
instance with multiple
<Union Of Features> components,
containing cultural, vegetation, and surface drainage features,
respectively.
FAQs
-
What is the purpose of this class?
The <Classification Related Features> class
exists to provide a mechanism for hierarchically organizing
<Feature Representation>
instances according to their (possibly elaborated) classification.
Constraints
Associated to (one-way) (inherited)
Associated by (one-way) (inherited)
Composed of (two-way) (inherited)
Composed of (two-way)
Composed of (two-way metadata) (inherited)
Component of (two-way) (inherited)
Notes
Associated to Notes
An association between two
<Feature Representation> instances
indicates that the environmental object(s) that they
represent have the semantic relationship indicated by
the <Base Association Data>
link object on the association relationship.
An association between a
<Geometry Hierarchy> instance and a
<Feature Representation> instance
indicates that the environmental object(s) that they
represent have the semantic relationship indicated by
the <Base Association Data>
link object on the association relationship.
An association between a
<Property Grid> instance and a
<Feature Representation> instance
indicates that the environmental object(s) represented by the
<Feature Representation> instance
and the <Property Grid> instance
(or some specific cell data within that
<Property Grid> instance) have the
semantic relationship indicated by the
<Base Association Data> link object
on the association relationship. Each associated
<Property Grid> instance indicates
whether the entire <Property Grid>
instance or only some specific cell data within it is participating
in the relationship in question.
Associated from Notes
An association between two
<Feature Representation> instances
indicates that the environmental object(s) that they
represent have the semantic relationship indicated by
the <Base Association Data>
link object on the association relationship.
An association between a
<Geometry Hierarchy> instance and a
<Feature Representation> instance
indicates that the environmental object(s) that they
represent have the semantic relationship indicated by
the <Base Association Data>
link object on the association relationship.
An association between a
<Property Grid> instance and a
<Feature Representation> instance
indicates that the environmental object(s) represented by the
<Feature Representation> instance
and the <Property Grid> instance
(or some specific cell data within that
<Property Grid> instance) have the
semantic relationship indicated by the
<Base Association Data> link object
on the association relationship. Each associated
<Property Grid> instance indicates
whether the entire <Property Grid>
instance or only some specific cell data within it is participating
in the relationship in question.
Composed of Notes
The <Image Mapping Function> components
support texture mapping information
for geometry that is to be derived from the
<Aggregate Feature> instance
by the consumer.
These <Image Mapping Function>
instances shall use <Image Anchor>
components to specify the mapping.
A <Presentation Domain> component is needed for
<Aggregate Feature> instances that are
significant only for a particular domain, such as radar.
Fields Notes
If the value of the
unique_descendants
field is SE_TRUE, each
descendant shall be unique in the sense that it shall
appear in only one branch of this aggregation.
Each descendant is a <Feature Representation> instance
within the component tree rooted at the
<Aggregate Feature> instance.
If unique_descendants
is SE_FALSE, at least one
<Feature Representation> instance
appears in more than one branch of the aggregation.
If the value of the
strict_organizing_principle
field is SE_TRUE, each
branch of this aggregation
strictly complies with the organizing principle for its
particular subclass. If this value is
SE_FALSE, at least
one branch does not strictly comply with the given
organizing principle. See the organizing principle constraint
for each specific subclass for details.
Prev: Classification Data.
Next: Classification Related Geometry.
Up:Index.
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Last updated: August 23, 2005
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Copyright © 2005 SEDRIS™
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