on towards higher performance and flexibility of automa- 
tic procedures aimed at the determination of digital 
elevation models. To achieve this, a new correlation 
conception has been developed, allowing for 
° the managment of the density values in the 
object space 
° the parallelization of the calculations within 
small regions, adopted to the surface morphology 
° the introduction of complex parametrizations of 
the surface, up to an introduction of discontinuities 
. the incorporation of several additional informa- 
tions, used for tuning and control purposes and neces- 
sary to support the introduced functionals. 
As first tests have shown, the concept seems to work, 
producing results of acceptable precision even in cases 
of surfaces with some higher morphologic complexity. 
In the next future the algorithm has to be completed 
followed by extensive tests to get an impression of the 
overall performance. 
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