mathematically continuous so that the features on both
sheets continue from one file (data set) into the other
without break, disjoin or discontinuity. In addition within
APS we are checking for the elevation attribute within the
contour line. In general there are many options
available, ASI has restricted the processing to a given
layer number(s) or feature code(s); and joining lines with
the same contour value (Regan & Armenakis, 1994).
Manual measurements of elevation points, using
conventional stereoplotter, is expensive and time KE
consuming. New techniques using automatic elevation
extraction, implemented in a softcopy photogrammetric
system, can generate massive amounts of elevation data
with reliable accuracy (Khames, Scarpace, 1995; AE
Ackerman, Krzystek, 1995). Future developments in this
area are expected to increase productivity and accuracy. m
as
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Arch. Photogramm. Remote Sensing, Vol. XXIX, Part B4, the
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Khames H. & Scarpace F., (1995) "An evaluation of an Adr
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ASPRS 1995, Charlotte, Vol. 2, pp 185-192 d
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Regan & Armenakis,( 1994), "Operational Aspects for the her
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996
