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Example(s)
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The <DRM Property Value> instances of a
representation of a lake might
include its EAC_SURFACE_MATERIAL_TYPE.
Consider the man-made materials that can be found on any surface,
such as cloth, carpet, asphalt, silk, metal, and natural materials,
such as wood. To specify the material making up a wooden wall
represented by a <DRM Polygon> instance, the
data provider represents it as
Figure 6.238 — <DRM Property Value> example
Consider an <DRM Areal Feature> representing
a surface covered with vegetation. To specify the type of vegetation,
the data provider gave it a <DRM Property Value>
component with a meaning of
EAC_VEGETATION_TYPE, and the value specifying the exact type
of vegetation.
Consider an <DRM Areal Feature> labeled as
“Red Field”, because the surface represented has clay soil
present. To describe the soil composition at some point or for some
surface, <DRM Property Value> instances are
used, so a <DRM Property Value> of the appropriate
attribute is attached to the <DRM Areal Feature>.
Consider acoustic response, that is, changes to characteristics of
objects in response to acoustic stimuli, such as the resonant
frequency of a plate, response (such as echo, phase shift, absorption,
diffraction), or frequency.
Consider electromagnetic emission, that is, the emission
characteristics of a geometric object or feature, including
the electromagnetic wavelengths, amplitudes, and directionality.
Examples include
- The thermal signature of a rock at noon is described by its
electromagnetic emission.
- The headlight of a truck.
Consider electromagnetic response, that is, changes to
characteristics of objects in response to electromagnetic stimuli.
Some examples of
such properties include reflective and specular characteristics of a
surface.
Consider hydrology, that is, an attribute describing some aspect of
the flow of water at a location or on a surface. For the
<DRM Polygon> instances that represent Salmon Creek,
an example hydrology property represented by
<DRM Property Value> instances is the average
speed of currents in the stream bed.
<DRM Property Value> instances can provide
metrics, measurements that that relate to scalar properties, such as
the elevation at a particular location.
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