International Archives of the Photogrammetry, Remote Sensing and Spatial Information Science
s, Vol XXXV, Part B7. Istanbul 2004
3.2.2
Chart
The EDM precise surveying was done to analyze the matching
errors of the complex geography information which is the base
in constructing the complex geography information of digital
map and digital chart.
It was the EDM surveying that the boundary line surveying of
digital map and digital chart used the GPS point acquired by the
GPS control point surveying.
The EDM surveying was done by using the two points located
in the wharf and output by the GPS Static surveying.
In this study, it took much time in office work. To do the
surveying first, any coordinate was given to the two points of
the wharf. And then, the EDM was done.
The figure 3.4 represents the coordinate of boundary lines
output by the EDM surveying on CAD.
The boundary line surveying to match the Map and
3
agai 1 1
Figure 3.4 The matching of digital map and digital chart.
(unit : m)
Node dx dy [^ + dy”
A -1.73 -5.44 5.71
B -0.78 -1.29 p51
C -3.70 -4.52 5.84
D 0.32 -0.60 0.68
E -7.24 -11.02 13.19
F -0.09 -4.20 4.20
RMS 3.41 5.64 6,59
Table 3.5 Matching analysis between digital chart and digital
map.
Figure 3.4 Digital Map and EDM Surveying.
(unit : m)
Node dx dy LS dy
A 0.70 0.90 1.14
B -0.96 -0.32 1.01
C -0.99 -0.84 0.84
D 0.32 -0.60 0.68
E 0.78 0.28 0.83
Pp 0.30 -0.79 0.85
| RMS 0.61 0.67 0.90
Table 3.4 Matching analysis between EDM surveying and
digital map on wharf.
The matching with the digital map was attempted by setting up
the points done EDM surveying at the wharf-side of the figure
3.4.
The table 3.4 is the arrangement of the elongation distance and
the deviation of the x, y that is the outcome of the EDM, in
each point on the digital map. When the EDM surveying point
is the datum point, the points of the wharf-side on the digital
map shows the mean +0.61m on x-axis, the mean -0.67m on y-
axis in the value of RMS. And the mean elongation distance is
0.9m. This is less than the average drawing allowable error, that
is, the one occurring on making allowance for 0.2mm of the
drawing allowable error in 1/5.000 and 1/10,000 map, about
2.24m by 1.34m.
And the figure 3.5 is the matching with Digital Chart and
Digital Map. This is done by using the coordinate of the
boundary point the EDM was carried out.
On the whole it is known that the errors were happened largely
in the southeastern direction. In the northern direction the error
was about 3.41m, in the eastern about 5.64m.
3.3 Analysis of the GPS observed value.
3.3.1 The accuracy analysis according to the geometric
strength of the GPS network.
The 3 points of Bong-Lae Mt., Jang-San Mt. and Um-Gaung
Mt. were selected as the control points in adjusting the given
GPS network. The figure 3.6 is the geometric arrangement of
these points and shows about 49°50" 14.64" 45238 21.20" ,
and 84°31' 24.16".
|
Bong-Lae Mt. |
|
X.
| LÀ
N => —
550400208" Teas
Ny
48928'47 49" €
su Keum-Ryun Mt.
SU
"n
E
MC 1595109.537
Um-Gaung Mt.
Figure 3.6 The geometric arrangement plan which is gotten
from GPS network adjustment.
The table 3.6 shows the errors that were achieved by the
network adjustment and the actual coordinate of the triangular
point. This shows the deviation between the coordinate of point
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