PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
October 2017
665
East of Greenwich. The defining azimuth at the point of or-
igin to Signal A is: α
o
= 317° 02´ 50.62˝. The “Russia Belts”
Grid System is used with the System 42 Datum; identical to
UTM except that the scale factor at origin is unity.
A civilian version used since 1952 is a modification of the
Russia Belts system in that the False Northing at origin was
f
= 49° 30´ North, the False Northing = 200 km, the False East-
ing = 500 km, and the scale factor at origin (mo) = 0.99992001.
Everything else remained the same as the standard Gauss-
Krüger Transverse Mercator Grid. Boundary treaties with
adjacent countries refer to ancient datums and grids that in-
clude the old double stereographic projections of the 19th and
early 20
th
centuries. The S-JTSK Krovak Projection is alive
and well in the Czech Republic for the 21
st
century.
U
pdate
Applied research in the department is in the first place directed
to the present needs of the branch of the Czech Office of
Surveying,Mapping andCadastre in thefield of geodetic control
networks, their update and integration within the modern
European geodetic control. Recently the project of incorporation
of the Czech and Slovak Astrogeodetic Network, together with
the primary networks of Austria, Hungary and Germany, into
the European terrestrial continental reference system ED87
has been accomplished. The department participated in the
extension of the new European reference frame EUREF to the
Czech and Slovak Republics, in the establishment of the Czech
zero-order GPS reference network and in its densification to
the average density 1 station/ 400 km
2
as well as in the direct
connection of the Czech GPS reference network with reference
networks of Germany and Austria. In the establishment of
GPS reference networks the department takes part by both
the observations and the processing by the scientific software
package. The most topical task is the establishment and
monitoring of the Czech National Geodynamical Network by
GPS technique. The network consists of 32 stations at which
GPS observations have beenperiodically repeated (twice a year)
since the spring 1995. These observations are supplemented
by levelling and gravity measurements. The objective of this
project is a stability assessment of the horizontal control
network and its integration with the vertical control network
of the Czech Republic. The department takes an active part
in the process of incorporation of the Czech national geodetic
control into the continental European geodetic control by
participation in the international projects EUREF and EUVN
(its realization is now in its initial stage). With the help of the
national GPS reference networks the present user terrestrial
reference frame (S-JTSK/95) has been improved and is now
passing through large scale disputations. For the cadastral
offices the local networks, densified by themselves by GPS
techniques, are tied to the national GPS reference network.
A reference quasigeoid model was computed for the territory
of the Czech Republic with an accuracy of about 5 cm which
makes it possible to determine sea level heights from GPS
observations at any place of the state territory. The stability
of the reference frame is continuously monitored by evaluation
of observations of a cluster of European IGS stations. For
the calibration and processing of the GPS technology, the
calibration network was established at Geodetic Observatory
Pecny and Skalka. In the field of the geodetic control networks
the department collaborates with the Land Survey Office and
with the Department of Advanced Geodesy of the Faculty of
Civil Engineering of the Czech University of Technology in
Prague. Last updated: 17.10.2005
The contents of this column reflect the views of the author, who is
responsible for the facts and accuracy of the data presented herein.
The contents do not necessarily reflect the official views or policies of
the American Society for Photogrammetry and Remote Sensing and/
or the Louisiana State University Center for GeoInformatics (C
4
G).
This column was previously published in
PE&RS
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ASPRS congratulates these recently Certified
and Re-certified individuals:
CERTIFIED PHOTOGRAMMETRIST
Mohannad Al-Durgham, Certification #1621
Effective August 11, 2017, expires August 11, 2022
CERTIFIED MAPPING SCIENTIST LIDAR
Demetrio Zourarakis, Certification # L017
Effective August 4, 2017, expires August 4, 2022
CERTIFIED REMOTE SENSING TECHNOLOGIST
Davtarica A. Hodge, Certification #236RST
Effective August 4, 2017, expires August 4, 2020
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