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Earth rotation and geodynamics / Janusz Bogusz in Geodesy and cartography, vol 64 n° 2 (December 2015)  

Public [article]  inGeodesy and cartography > vol 64 n° 2 (December 2015) . - pp 201 - 242 Titre : Earth rotation and geodynamics Type de document : Article/Communication Auteurs : Janusz Bogusz, Auteur ; Alexander Brzezinski, Auteur ; Wieslaw Kosek, Auteur ; Jolanta Nastula, Auteur Année de publication : 2015 Article en page(s) : pp 201 - 242 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes IGN] champ géomagnétique [Termes IGN] géodynamique [Termes IGN] marée terrestre [Termes IGN] Pologne [Termes IGN] positionnement par GNSS [Termes IGN] positionnement par télémétrie laser sur satellite [Termes IGN] rotation de la Terre Résumé : (auteur) This paper presents the summary of research activities carried out in Poland in 2011-2014 in the field of Earth rotation and geodynamics by several Polish research institutions. It contains a summary of works on Earth rotation, including evaluation and prediction of its parameters and analysis of the related excitation data as well as research on associated geodynamic phenomena such as geocentre motion, global sea level change and hydrological processes. The second part of the paper deals with monitoring of geodynamic phenomena. It contains analysis of geodynamic networks of local, and regional scale using space (GNSS and SLR) techniques, Earth tides monitoring with gravimeters and water-tube hydrostatic clinometer, and the determination of secular variation of the Earth’ magnetic field. Numéro de notice : A2015--018 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/geocart-2015-0013 En ligne : http://dx.doi.org/10.1515/geocart-2015-0013 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80814 [article]

Theoretical geodesy / Andrzej Borkowski in Geodesy and cartography, vol 64 n° 2 (December 2015)  

Public [article]  inGeodesy and cartography > vol 64 n° 2 (December 2015) . - pp 261 - 279 Titre : Theoretical geodesy Type de document : Article/Communication Auteurs : Andrzej Borkowski, Auteur ; Wieslaw Kosek, Auteur Année de publication : 2015 Article en page(s) : pp 261 - 279 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie [Termes IGN] estimation statistique [Termes IGN] fiabilité des données [Termes IGN] mouvement du pôle [Termes IGN] série temporelle Résumé : (auteur) The paper presents a summary of research activities concerning theoretical geodesy performed in Poland in the period of 2011-2014. It contains the results of research on new methods of the parameter estimation, a study on robustness properties of the M-estimation, control network and deformation analysis, and geodetic time series analysis. The main achievements in the geodetic parameter estimation involve a new model of the M-estimation with probabilistic models of geodetic observations, a new Shift-Msplit estimation, which allows to estimate a vector of parameter differences and the Shift-Msplit(+) that is a generalisation of Shift-Msplit estimation if the design matrix A of a functional model has not a full column rank. The new algorithms of the coordinates conversion between the Cartesian and geodetic coordinates, both on the rotational and triaxial ellipsoid can be mentioned as a highlights of the research of the last four years. New parameter estimation models developed have been adopted and successfully applied to the control network and deformation analysis. New algorithms based on the wavelet, Fourier and Hilbert transforms were applied to find time-frequency characteristics of geodetic and geophysical time series as well as time-frequency relations between them. Statistical properties of these time series are also presented using different statistical tests as well as 2nd, 3rd and 4th moments about the mean. The new forecasts methods are presented which enable prediction of the considered time series in different frequency bands. Numéro de notice : A2015--019 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/geocart-2015-0015 En ligne : http://dx.doi.org/10.1515/geocart-2015-0015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80815 [article]

Irregular variations in GPS time series by probability and noise analysis / Anna Klos in Survey review, vol 47 n° 342 (May 2015)  

Public [article]  inSurvey review > vol 47 n° 342 (May 2015) . - pp 163 - 173 Titre : Irregular variations in GPS time series by probability and noise analysis Type de document : Article/Communication Auteurs : Anna Klos, Auteur ; Janusz Bogusz, Auteur ; Mariusz Figurski, Auteur ; Wieslaw Kosek, Auteur Année de publication : 2015 Article en page(s) : pp 163 - 173 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal [Termes IGN] bruit (théorie du signal) [Termes IGN] bruit blanc [Termes IGN] bruit rose [Termes IGN] classification par maximum de vraisemblance [Termes IGN] écart type [Termes IGN] filtrage du bruit [Termes IGN] métrique [Termes IGN] récepteur GPS [Termes IGN] série temporelle Résumé : (auteur) The character of the topocentric components in ETRF2000(R08) from the Polish ASG-EUPOS system was analysed using skewness and kurtosis derived from the data probability density function. The data from 115 permanent GPS stations with a time span of more than 5 years were used. The main goal of this research was to show that any unmodelled systematics can disrupt the results. The obtained median values of skewness and kurtosis clearly indicate the discrepancies between the assumed normality of the GPS time series distribution and the reality, mainly due to stochastic and/or deterministic parts that are still present in the data. The quadratic relationship between skewness and kurtosis was developed with the empirically determined constants. The noise analysis with the Maximum Likelihood Estimation was also performed with the assumptions of white and white plus power-law noise. The estimated spectral indices for power law noises are close to −1 (flicker noise). The uncertainties of the intraplate velocities with white and white plus power law noise assumptions were calculated. It was shown that these uncertainties can be underestimated up to 5 mm/year. Additionally we made 1000 simulation which were aimed at showing how the values of skewness and kurtosis are changed when some mismodelled part of the data remains in the time series. We assumed different values of trend (1 and 6 mm/year), seasonal amplitudes (1 and 6 mm) and offsets (3 and 10 mm) with flicker noise of 1 mm amplitude to see how the metrics we use are biased. Numéro de notice : A2015-930 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1179/1752270614Y.0000000133 En ligne : https://doi.org/10.1179/1752270614Y.0000000133 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79735 [article]