Optimal biased Kriging: Homeogram tapering and applications to geoid undulations in Korea [PDF]
Journal of Geodetic Science, 2018 This article studies the Optimal Biased Kriging (OBK) approach which is an alternative geostatistical method that gives up the unbiasedness condition of Ordinary Kriging (OK) to gain an improved Mean Squared Prediction Error (MSPE).
Schaffrin B., Bae T.-S., Felus Y.
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Evaluation of GOCE-based global gravity field models over Japan after the full mission using free-air gravity anomalies and geoid undulations [PDF]
Earth, Planets and Space, 2017 The performance of Gravity field and steady-state Ocean Circulation Explorer (GOCE) global gravity field models (GGMs), at the end of GOCE mission covering 42 months, is evaluated using geoid undulations and free-air gravity anomalies over Japan ...
Patroba Achola Odera, Yoichi Fukuda
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Gravity-enhanced representation of measured geoid undulations using equivalent sources [PDF]
Geophysical Journal International, 2004 SUMMARY Direct Global Positioning System measurement of geoid undulations on accurately levelled stations, usually tens of kilometres apart, can be interpolated by taking advantage of denser surveys of free-air gravity anomalies covering the same area.
Fernando Guspí +2 more
semanticscholar +3 more sources
Determination of Nigerian Geoid Undulations from Spherical Harmonic Analysis
Applied Physics Research, 2011 Geoid undulation has been determined for Nigeria in order to demonstrate its relationship with topography and the dynamic structure of the Earth’s interior. Spherical harmonic expansion using the Earth Gravitational Model 2008 (EGM2008) referenced to the WGS84 (World Geodetic System 1984) with coefficients extending to degree 2190 and order 2159 was ...
A. A. Okiwelu, E. E. Okwueze, Ikechi Ude
semanticscholar +5 more sources
Spatial uncertainty of a geoid undulation model in Guayaquil, Ecuador
Open Geosciences, 2017 Geostatistics is a discipline that deals with the statistical analysis of regionalized variables. In this case study, geostatistics is used to estimate geoid undulation in the rural area of Guayaquil town in Ecuador.
Chicaiza E.G. +3 more
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A comparison of geoid undulations for west central Greenland [PDF]
Journal of Geophysical Research: Solid Earth, 1997 The accuracy of a new local gravity field model, GEOID94A, is examined at a site on the western Greenland ice sheet. The model, developed by the Danish National Survey and Cadastre, incorporates several new gravity data sets including an extensive amount of airborne gravity data. Model‐derived geoid undulations were compared to independently determined
D. R. Roman +6 more
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Modelling local GPS/levelling geoid undulations using Support Vector Machines
Periodica Polytechnica Civil Engineering, 2008 Support vector machines (SVM) with wavelet kernel has been applied to the correcting gravimetric geoid using GPS/levelling data. These data were divided into a training and a validation set in order to ensure the extendability of the approximation of the corrector surface.
Piroska Zaletnyik +2 more
semanticscholar +4 more sources
MARINE GEOID UNDULATION ASSESSMENT OVER SOUTH CHINA SEA USING GLOBAL GEOPOTENTIAL MODELS AND AIRBORNE GRAVITY DATA [PDF]
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2016 Global geopotential models (GGMs) are vital in computing global geoid undulations heights. Based on the ellipsoidal height by Global Navigation Satellite System (GNSS) observations, the accurate orthometric height can be calculated by adding precise and ...
N. M. Yazid +6 more
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Impact of DHM resolution on gravity anomalies and geoid undulations: case study for Egypt [PDF]
NRIAG Journal of Astronomy and GeophysicsThis study aims to estimate the effect of the resolution of the available Digital Height Models (DHMs) on the reduced gravity anomalies and the final computed gravimetric geoid. The region of Egypt is taken to be a prototype test.
Mostafa Ashry +3 more
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Determination of the Geoid–Quasigeoid Separation Using GGI Method
Remote SensingThe determination of the geoid–quasigeoid separation (GQS) is most often based on the use of Bouguer gravity anomalies or disturbances with additional corrections, which allow for the determination of so-called complete or accurate GQS values. This study
Marek Trojanowicz +2 more
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