Results 141 to 150 of about 742 (185)

Geoid Height Optimisation via Sequential Least Squares Method

1997
The methodology for the integration of heterogeneous height differences (from GPS vectors, precise gravimetric geoid and levelling) in one common adjustment via a sequential process of Bayesian Least Squares and constraint equations (BAYCON) was proposed in 1993, at the IAG meeting in Beijing. This paper discusses the adjustment results of the southern
Zarina Ahmad-Berger, A. H. W. Kearsley
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Harmonic continuation and gridding effects on geoid height prediction

Bulletin G�od�sique, 1992
Least-squares collocation and Stokes integral formula, as implemented using the Fast Fourier Technique, handle the harmonic downward continuation problem quite differently. FFT furthermore requires gridded data, amplifying the difference of methods.
C. C. Tscherning, R. Forsberg
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Geoid height anomalies over the Cape Verde Rise

Marine Geophysical Researches, 1982
Geoid height anomalies, as determined by satellite altimetry, suggest that the Cape Verde Rise is in local isostatic equilibrium, supported by a low-density root of altered lithosphere. A depth anomaly map shows the Cape Verde Rise to be approximately 1600 km wide and 2km high.
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Determination of geoid height at Breid Bay, east Antarctica

Journal of Geophysical Research: Solid Earth, 1991
By the combined observation of satellite Doppler positioning, Global Positioning System (GPS) relative carrier phase measurement, and ocean tide observation, we obtained the geoid height at Breid Bay (70°12′S, 23°47′E) as 16.8 m above the World Geodetic System 1984 (WGS84) Earth ellipsoid. The broadcast ephemeris satellite Doppler positioning was made,
K. Shibuya, Y. Fukuda, Y. Michida
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Determination of Geoid Heights by GPS and Precise Trigonometric Levelling

Survey Review, 2006
Abstract Most commonly used method for the determination of geoid is the evaluation of GPS (Global Positioning System) and levelling measurements together. Despite the fact that geometric levelling (GL) is in general easy and practicable, it is a measurement method that is hard and uneconomic to apply particularly in mountainous, hilly and rugged areas.
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Geoid height versus topography for oceanic plateaus and swells

Journal of Geophysical Research: Solid Earth, 1989
Oceanic plateaus and swells are a major component of the seafloor topography, yet they remain among the most poorly understood features. This is especially true of the oceanic plateaus which show large variations in crustal thickness. To determine the depth and mode of compensation for 53 of the largest plateaus and swells, we analyzed the relationship
David T. Sandwell, Kevin R. MacKenzie
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Geoid Heights, Geoid Height Differences, and Mean Gravity Anomalies from 'Low-Low' Satellite-to-Satellite Tracking - An Error Analysis,

1980
Abstract : The mathematical model for a simultaneous estimation of improved orbital parameters and an approximation of the earth's gravity field from range rate observations in an SST 'low-low' experiment is described. In a somewhat simplified model an error analysis for the estimation of geoid heights, geoid height differences 1 deg x 1 deg mean ...
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Geoid determination in central Spain from gravity and height data

Bulletin Géodésique, 1993
The least-squares collocation method has been used for the computation of a geoid solution in central Spain, combining a geopotential model complete to degree and order 360, gravity anomalies and topographic information. The area has been divided in two 1-degrees x 1-degrees blocks and predictions have been done in each block with gravity data spacing ...
A. J. Gil, M. J. Sevilla, G. Rodríguez-Caderot   +2 more
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Application of Fuzzy Logic Theory to Geoid Height Determination

2007
Geoid determination is nowadays an important scientific problem in the fields of Geosciences. Ellipsoidal and orthometric heights are commonly used height systems in geodesy. Ellipsoidal height, measured from satellite such as GPS and GLONASS, is reckoned from ellipsoid. On the other hand orthometric height is measured from geoid.
Mehmet Yιlmaz, Mustafa Acar, Tevfik Ayan, Ersoy Arslan   +3 more
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HEIGHTS ABOVE THE GEOID FOR MAPPING CONTROL BY DOPPLER TRANSLOCATION

Survey Review, 1988
AbstractTranslocated poppler observations with small numbers of passes are combined with differences in geoid model heights to determine orthometric height differences between a known base station and unknown field stations. The method was tested on 15 base lines in Ghana up to 554 Km and the results showed the standard error of agreement between the 3
M. C. Breach, P. Maye
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