Geography Reference
In-Depth Information
Passable terrain (GO)—real speed is approaching maximum speed;
Terrain passable with restrictions (SLOW GO)—real speed is lower or signifi-
cantly lower than maximum speed, obstacles can be overcome;
Impassable terrain (NO GO)—obstacles cannot be overcome.
It is possible to determine the basic degrees of CCM for each transport or
fighting vehicle because of their technical parameters (chassis type, power of
engine, transmission system etc.), or consider the CCM of the weakest vehicle in
the unit.
Specific degree of CCM determination on given part of terrain is possible to
express as a complex function in which all impacts of individual geographic factors
are evaluated as the coefficients of deceleration
and expressed as a number
from the interval of 0-1. The individual coefficient of deceleration shows the real
(simulated) speed of vehicle
v
in the landscape in the confrontation with the
maximum speed of given vehicle
v
max
. The impact of all the 7 basic geographic
factors can be expressed by the formula:
C
i
'
'
v ¼ v
max
Y
7
C
i
ð
7
Þ
i¼
1
The main coefficients of deceleration and the theory of their determination are
listed in the Table
2
(Rybansky and Vala
2010
).
These coefficients are thereinafter indexed and classified into particular discrete
factors listed in the Table
3
.
According to the theory, each basic coefficient is calculated by the next formula:
C
i
¼
Y
m
C
j
,
i ¼
1,
,7,
m 2
f
1
;
...
;
6
g
ð
8
Þ
...
j¼
1
If there is the assumption that the route of vehicle movement, including direct
segment, consists of various sub-sections, in which values of geographical factors
are unchanged, the final degree of CCM can be determined as a cost of the given
segment.
For given vehicle (its technical properties) the values of deceleration coefficients
are calculated from ascertained properties of geographic objects stored in the spatial
geo-database. Using formulas (
7
) and (
8
) it is possible to create a cost map in which
the value of each pixel is the final (modeled) speed. The
cost map
can be used as a
source for calculation of the shortest, fastest, cheapest or safest path.
Similarly to HLS determination it is possible to consider the quality and cer-
tainty of digital data describing the geographic features. Crisp sets or fuzzy logic is
also applicable for cost map evaluation. The following paragraphs describe shortly
both possibilities for which the features from Brno and its vicinity selected from
standard spatial database DMU25 produced by the Military Geographic Service of
the Army of the Czech Republic was used. The list of used features and their