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Mapping with GNSS
Published in Basudeb Bhatta, Global Navigation Satellite Systems, 2021
One of the most important functions of geodesy is the determination of the precise position of points in relation to a well-defined reference system or datum. Hence geodesy is both the science of determining the ‘figure of the earth’ and the set of practical tools for capturing spatial data. However, it is customary to distinguish between those techniques which are ‘geodetic’, capable of the most precise position determination, from those which are not able to satisfy the same stringent accuracy requirements. There is, of course, a continuous spectrum of positioning accuracy requirements from high to low. This has long been recognised by the hierarchical system used in control surveying. Geodesy provides the most fundamental control or geodetic network (or framework of physical benchmarks), which is then progressively ‘broken down’ or ‘densified’ using less accurate techniques.
The improved method for digital elevation modelling undermined territories of Donbass on satellite images
Published in Vladimir Litvinenko, Topical Issues of Rational Use of Natural Resources 2019, 2019
R.A. Kovnir, N.N. Grishchenkov
In order to test the program in the summer of 2018, a series of observations was made to determine the coordinates of points in the WGS-84 coordinate system by satellite geodesy methods at the points of the state geodetic network (SGN) with known coordinates in the SK-42 coordinate system. The results of a series of satellite observations made it possible to perform a fairly complete and reliable testing of the program.
Assessing the state of buildings’ foundations and residual lide of their bearing capacity
Published in Rashid Mangushev, Askar Zhussupbekov, Yoshinori Iwasaki, Igor Sakharov, Geotechnics Fundamentals and Applications in Construction: New Materials, Structures, Technologies and Calculations, 2019
L.Yu. Stupishin, S.G. Emelyanov, M.L. Moshkevich, F.V. Altukhov
Meanwhile, data on measurements are usually quite reliable and easily verifiable. During building delivery, it is necessary to submit documents including information about the geodetic network on which construction quality control was based.
Geocentric Datum of Australia 2020: the first Australian datum developed from a rigorous continental-scale adjustment
Published in Journal of Spatial Science, 2023
Craig Harrison, Nicholas Brown, John Dawson, Roger Fraser
For the full national geodetic network, the median is a more appropriate statistic to use, since the distribution of uncertainties is not Gaussian and has a long tail of large uncertainties. This is especially true for the vertical uncertainties since some stations have estimated heights, which require larger uncertainties. The median horizontal positional uncertainty of the full national geodetic network is 20.2 mm, and the median vertical positional uncertainty is 100.8 mm.