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Mass evolution of Mediterranean, Black, Red, and Caspian Seas from GRACE and altimetry : accuracy assessment and solution calibration / B. D. Loomis in Journal of geodesy, vol 91 n° 2 (February 2017)
[article]
Titre : Mass evolution of Mediterranean, Black, Red, and Caspian Seas from GRACE and altimetry : accuracy assessment and solution calibration Type de document : Article/Communication Auteurs : B. D. Loomis, Auteur ; Scott B. Luthcke, Auteur Année de publication : 2017 Article en page(s) : pp 195 - 206 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Caspienne, mer
[Termes IGN] données altimétriques
[Termes IGN] données GRACE
[Termes IGN] étalonnage des données
[Termes IGN] masse d'eau
[Termes IGN] Méditerranée, mer
[Termes IGN] Noire, mer
[Termes IGN] résidu
[Termes IGN] Rouge, mer
[Termes IGN] série temporelleRésumé : (Auteur) We present new measurements of mass evolution for the Mediterranean, Black, Red, and Caspian Seas as determined by the NASA Goddard Space Flight Center (GSFC) GRACE time-variable global gravity mascon solutions. These new solutions are compared to sea surface altimetry measurements of sea level anomalies with steric corrections applied. To assess their accuracy, the GRACE- and altimetry-derived solutions are applied to the set of forward models used by GSFC for processing the GRACE Level-1B datasets, with the resulting inter-satellite range-acceleration residuals providing a useful metric for analyzing solution quality. We also present a differential correction strategy to calibrate the time series of mass change for each of the seas by establishing the strong linear relationship between differences in the forward modeled mass and the corresponding range-acceleration residuals between the two solutions. These calibrated time series of mass change are directly determined from the range-acceleration residuals, effectively providing regionally-tuned GRACE solutions without the need to form and invert normal equations. Finally, the calibrated GRACE time series are discussed and combined with the steric-corrected sea level anomalies to provide new measurements of the unmodeled steric variability for each of the seas over the span of the GRACE observation record. We apply ensemble empirical mode decomposition (EEMD) to adaptively sort the mass and steric components of sea level anomalies into seasonal, non-seasonal, and long-term temporal scales. Numéro de notice : A2017-063 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0952-3 En ligne : http://dx.doi.org/10.1007/s00190-016-0952-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84277
in Journal of geodesy > vol 91 n° 2 (February 2017) . - pp 195 - 206[article]A drift line bias estimator: ARMA-based filter or calibration method, and its application in BDS/GPS-based attitude determination / Zhang Liang in Journal of geodesy, vol 90 n° 12 (December 2016)
[article]
Titre : A drift line bias estimator: ARMA-based filter or calibration method, and its application in BDS/GPS-based attitude determination Type de document : Article/Communication Auteurs : Zhang Liang, Auteur ; Hou Yanqing, Auteur ; Wu Jie, Auteur Année de publication : 2016 Article en page(s) : pp 1331 - 1343 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] échantillonnage de signal
[Termes IGN] erreur systématique
[Termes IGN] estimateur
[Termes IGN] étalonnage des données
[Termes IGN] filtrage du signal
[Termes IGN] positionnement ponctuel précis
[Termes IGN] signal BeiDou
[Termes IGN] signal GPSRésumé : (Auteur) The multi-antenna synchronized receiver (using a common clock) is widely applied in GNSS-based attitude determination (AD) or terrain deformations monitoring, and many other applications, since the high-accuracy single-differenced carrier phase can be used to improve the positioning or AD accuracy. Thus, the line bias (LB) parameter (fractional bias isolating) should be calibrated in the single-differenced phase equations. In the past decades, all researchers estimated the LB as a constant parameter in advance and compensated it in real time. However, the constant LB assumption is inappropriate in practical applications because of the physical length and permittivity changes of the cables, caused by the environmental temperature variation and the instability of receiver-self inner circuit transmitting delay. Considering the LB drift (or colored LB) in practical circumstances, this paper initiates a real-time estimator using auto regressive moving average-based (ARMA) prediction/whitening filter model or Moving average-based (MA) constant calibration model. In the ARMA-based filter model, four cases namely AR(1), ARMA(1, 1), AR(2) and ARMA(2, 1) are applied for the LB prediction. The real-time relative positioning model using the ARMA-based predicting LB is derived and it is theoretically proved that the positioning accuracy is better than the traditional double difference carrier phase (DDCP) model. The drifting LB is defined with a phase temperature changing rate integral function, which is a random walk process if the phase temperature changing rate is white noise, and is validated by the analysis of the AR model coefficient. The auto covariance function shows that the LB is indeed varying in time and estimating it as a constant is not safe, which is also demonstrated by the analysis on LB variation of each visible satellite during a zero and short baseline BDS/GPS experiment. Compared to the DDCP approach, in the zero-baseline experiment, the LB constant calibration (LBCC) and MA approaches improved the positioning accuracy of the vertical component, while slightly degrading the accuracy of the horizontal components. The ARMA(1, 0) model, however, improved the positioning accuracy of all three components, with 40 and 50 % improvement of the vertical component for BDS and GPS, respectively. In the short baseline experiment, compared to the DDCP approach, the LBCC approach yielded bad positioning solutions and degraded the AD accuracy; both MA and ARMA-based filter approaches improved the AD accuracy. Moreover, the ARMA(1, 0) and ARMA(1, 1) models have relatively better performance, improving to 55 % and 48 % the elevation angle in ARMA(1, 1) and MA model for GPS, respectively. Furthermore, the drifting LB variation is found to be continuous and slowly cumulative; the variation magnitudes in the unit of length are almost identical on different frequency carrier phases, so the LB variation does not show obvious correlation between different frequencies. Consequently, the wide-lane LB in the unit of cycle is very stable, while the narrow-lane LB varies largely in time. This reasoning probably also explains the phenomenon that the wide-lane LB originating in the satellites is stable, while the narrow-lane LB varies. The results of ARMA-based filters are better than the MA model, which probably implies that the modeling for drifting LB can further improve the precise point positioning accuracy. Numéro de notice : A2016-805 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-016-0926-5 En ligne : http://dx.doi.org/10.1007/s00190-016-0926-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82593
in Journal of geodesy > vol 90 n° 12 (December 2016) . - pp 1331 - 1343[article]Knowledge transfer for large-scale urban growth modeling based on formal concept analysis / Jinyao Lin in Transactions in GIS, vol 20 n° 5 (October 2016)
[article]
Titre : Knowledge transfer for large-scale urban growth modeling based on formal concept analysis Type de document : Article/Communication Auteurs : Jinyao Lin, Auteur ; Xia Li, Auteur Année de publication : 2016 Article en page(s) : pp 684 – 700 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] automate cellulaire
[Termes IGN] croissance urbaine
[Termes IGN] découverte de connaissances
[Termes IGN] étalonnage des données
[Termes IGN] Kouangtoung (Chine)
[Termes IGN] modèle conceptuel de données localisées
[Termes IGN] modélisation spatialeRésumé : (auteur) Cellular automata (CA) are useful for studies on urban growth and land-use changes. Although various methods have been developed to define transition rules, modeling urban growth of large areas remains a tough challenge owing to heterogeneous geographical features. To address the problem, we present a novel method based on the combination of Formal Concept Analysis (FCA) and knowledge transfer techniques. FCA is used to solicit association rules among cities within a large area. This method can provide a theoretical basis for the knowledge transfer process. A cutting-edge algorithm called TrAdaBoost is then integrated with the commonly-used Logistic-CA as the modeling framework. The proposed method is applied to the urban growth modeling of Guangdong Province, a large region with 21 cities in China, from 2005 to 2008. Compared with traditional methods, this method can achieve better results at the provincial and local levels, according to the experiments. The combination of FCA and knowledge transfer is expected to provide a useful tool for calibrating large-scale urban CA models. Numéro de notice : A2016-997 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12172 En ligne : http://dx.doi.org/10.1111/tgis.12172 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83777
in Transactions in GIS > vol 20 n° 5 (October 2016) . - pp 684 – 700[article]
Titre : Filtrage de Kalman à bruits corrélés pour le positionnement précis Type de document : Mémoire Auteurs : Ulrich Mambou Kuipou, Auteur Editeur : Le Mans : Ecole Supérieure des Géomètres et Topographes ESGT Année de publication : 2016 Importance : 75 p. Format : 21 x 30 cm Note générale : bibliographie
Mémoire présenté en vue d'obtenir le diplôme d'Ingénieur CNAM, Spécialité Géomètre et TopographeLangues : Français (fre) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] analyse de variance
[Termes IGN] auscultation topographique
[Termes IGN] bruit blanc
[Termes IGN] corrélation temporelle
[Termes IGN] estimateur
[Termes IGN] étalonnage des données
[Termes IGN] filtre de Kalman
[Termes IGN] méthode de Monte-Carlo par chaînes de Markov
[Termes IGN] méthode des moindres carrés
[Termes IGN] méthode du maximum de vraisemblance (estimation)
[Termes IGN] précision du positionnement
[Termes IGN] topométrie de précisionRésumé : (auteur) Le filtre de Kalman à bruits corrélés peut être considéré comme une alternative aux solutions de filtrage classique, car il améliore la précision du positionnement. Les applications de ce nouveau filtre seraient très intéressantes pour le couplage de mesures dans les domaines suivants : photogrammétrie, télédétection aérienne, bathymétrie et «mobile mapping». L’objectif visé par ce travail de fin d’études, est d’évaluer les performances du filtre de Kalman à bruits corrélés dans une expérience d’auscultation. Dans l’optique de mettre en évidence la puissance de ce filtre, il y a lieu d’estimer par le maximum de vraisemblance, d’une part la variance du modèle d’évolution et d’autre part la corrélation des modèles (même corrélation de bruits, pour les modèles d’évolution et d’observation) en fixant au préalable une structure de corrélation aux dits modèles. Note de contenu : Introduction
1- Expérience de Bogatin
2- Méthode de calibration et résultat du filtrage de Kalman
3- Bruits corrélés : estimation et filtrage de Kalman à bruits corrélés
4- Applications sur des données réellesNuméro de notice : 24612 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Mémoire ingénieur ESGT Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92178 Documents numériques
en open access
Filtrage de Kalman à bruits ... - pdf auteurAdobe Acrobat PDF A merging solution for close-range DEMs to optimize surface coverage and measurement resolution / Stéphane Bertin in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 1 (January 2016)
[article]
Titre : A merging solution for close-range DEMs to optimize surface coverage and measurement resolution Type de document : Article/Communication Auteurs : Stéphane Bertin, Auteur ; Heide Friedrich, Auteur ; Patrice Delmas, Auteur Année de publication : 2016 Article en page(s) : pp 31 – 40 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] étalonnage des données
[Termes IGN] fusion de données
[Termes IGN] gravier
[Termes IGN] intégration de données
[Termes IGN] lit
[Termes IGN] modèle numérique de surface
[Termes IGN] photogrammétrie métrologique
[Termes IGN] torrentRésumé : (auteur) The process of efficient and effective DEM merging is increasingly becoming more important. To allow DEM analysis for features of different scales, an increase in surface coverage cannot result in reduced measurement resolution. It is thus inevitable that merging individual high-resolution DEMs will become common practice for applications such as hydraulic roughness studies for fluvial surfaces. This paper presents an efficient and effective merging solution, whereby accurate co-registration of individual DEMs collected from consistent viewpoints and standard averaging for overlapping elevations ensure seamless merging. The presented method is suitable for DEMs collected using any measurement technology, as long as individual DEMs overlap and are arranged on regular grids. The merging solution is applied to the study of a laboratory gravel bed measured with vertical stereo photogrammetry at the grain scale (>106 points/ m2). We show that the approach can be integrated into the DEM collection workflow at the design stage, which optimizes the measurement performance. We present how resampling before merging can be beneficial to keep data handling requirements practical, whilst ensuring accurate surface representation. Finally, the effect of scale variation is studied, showing that seamless merging applies to DEMs with variable resolution. Numéro de notice : A2016-049 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.83.1.31 En ligne : https://doi.org/10.14358/PERS.83.1.31 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79653
in Photogrammetric Engineering & Remote Sensing, PERS > vol 82 n° 1 (January 2016) . - pp 31 – 40[article]Numerical and experimental evaluation of terrestrial LiDAR for parameterizing centimeter-scale sea ice surface roughness / Jack C. Landy in IEEE Transactions on geoscience and remote sensing, vol 53 n° 9 (September 2015)PermalinkCalibration of SAR polarimetric images by means of a covariance matching approach / Alberto Villa in IEEE Transactions on geoscience and remote sensing, vol 53 n° 2 (February 2015)PermalinkPermalinkCalibration of area based diameter distribution with individual tree based diameter estimates using airborne laser scanning / Qing Xu in ISPRS Journal of photogrammetry and remote sensing, vol 93 (July 2014)PermalinkAccuracy assessment of water vapour measurements from in-situ and remote sensing techniques during the DEMEVAP 2011 campaing at OHP / Olivier Bock in Atmospheric measurement techniques, vol 6 n° 10 (October 2013)PermalinkDORIS and GPS monitoring of the Gavdos calibration site in Crete / Pascal Willis in Advances in space research, vol 51 n° 8 (April 2013)PermalinkCalibration of wet tropospheric delays in GPS observation using Raman lidar measurements / Pierre Bosser (2012)PermalinkA procedure for radiometric recalibration of Landsat 5 TM reflective-band data / Gyanesh Chander in IEEE Transactions on geoscience and remote sensing, vol 48 n° 1 Tome 2 (January 2010)PermalinkGetting down to business: SMOS operations and products / S. Mecklenburg in ESA bulletin, n° 137 (February 2009)PermalinkFuzzy inference guided cellular automata urban-growth modelling using multi-temporal satellite images / S. Al-Kheder in International journal of geographical information science IJGIS, vol 22 n°11-12 (november 2008)Permalink