Figure 3. Sheet sample with tie points 0 and control points A
3.2 Practical application
A good preparation was required in order to:
1. Select tie points and ensure their optimal locations
2. Ensure availability and existence of control points.
3. Ensure sharp identification of each point
4. Select the right type of transformation.
An individual local co-ordinate system is attached to each sheet
and only some of the sheets are referenced to the state system.
Because of this type of sheet configuration and the associated
paper deformation we applied affine plane transformation. All
sheets were numbered according their local system. All
precautions were taken to ensure the presence of all required
points according to the guiding principle established. The main
objective was to realise geographic information system in
support of land management of the industrial zone as
formulated by the EGZIA principal manager. The area of
interest is spread over 25 AO sheets covering roughly 3000 ha at
scale approximately 1:4000.
Once the parameters were calculated the entire digitised data set
was transformed into unique state co-ordinate system .
4. CONCLUSION
The adjustment allowed us to manipulate the data since it was
presented in a same and unique co-ordinate system.
The simultaneous adjustment of all sheets prevented
duplications or missing data .The basic relations and the
cadastral features were easily attached allowing entry of owner
and property attributes. Misclosures of lines and polygons,
sheet edge mismatches, and duplicate co-ordinates of the same
point disappeared as a result of the homogeneity of the adjusted
sheets.
This adjustment method we described here is not the only
option. It can be extended to include the adjustment where the
constraints on detailed points are used. Adding these
considerations will let surely this approach of adjustment be
more efficient.
180
Planche 8
Planche 9
Planche 25
Figure 4 Sheets 8,9, and 25
Radwa
James,
Fritsch.
systems
Week 1
Amer,
ITC Le
Stefano
Notes.
