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A fast and accurate algorithm for high-frequency trans-ionospheric path length determination / Dudy D Wijaya in Journal of geodesy, vol 89 n° 12 (december 2015)
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Titre : A fast and accurate algorithm for high-frequency trans-ionospheric path length determination Type de document : Article/Communication Auteurs : Dudy D Wijaya, Auteur Année de publication : 2015 Article en page(s) : pp 1183 - 1196 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] longueur d'onde
[Termes IGN] réfraction atmosphérique
[Termes IGN] troposphèreRésumé : (auteur) This paper presents a fast and accurate algorithm for high-frequency trans-ionospheric path length determination. The algorithm is merely based on the solution of the Eikonal equation that is solved using the conformal theory of refraction. The main advantages of the algorithm are summarized as follows. First, the algorithm can determine the optical path length without iteratively adjusting both elevation and azimuth angles and, hence, the computational time can be reduced. Second, for the same elevation and azimuth angles, the algorithm can simultaneously determine the phase and group of both ordinary and extra-ordinary optical path lengths for different frequencies. Results from numerical simulations show that the computational time required by the proposed algorithm to accurately determine 8 different optical path lengths is almost 17 times faster than that required by a 3D ionospheric ray-tracing algorithm. It is found that the computational time to determine multiple optical path lengths is the same with that for determining a single optical path length. It is also found that the proposed algorithm is capable of determining the optical path lengths with millimeter level of accuracies, if the magnitude of the squared ratio of the plasma frequency to the transmitted frequency is less than 1.33×10−3, and hence the proposed algorithm is applicable for geodetic applications. Numéro de notice : A2015-886 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0841-1 En ligne : https://doi.org/10.1007/s00190-015-0841-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79433
in Journal of geodesy > vol 89 n° 12 (december 2015) . - pp 1183 - 1196[article]InSAR assessment of surface deformations in urban coastal terrains associated with groundwater dynamics / Jonathan C. L. Normand in IEEE Transactions on geoscience and remote sensing, vol 53 n° 12 (December 2015)
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Titre : InSAR assessment of surface deformations in urban coastal terrains associated with groundwater dynamics Type de document : Article/Communication Auteurs : Jonathan C. L. Normand, Auteur ; Essam Heggy, Auteur Année de publication : 2015 Article en page(s) : pp 6356 - 6371 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] aquifère
[Termes IGN] bande C
[Termes IGN] déformation de la croute terrestre
[Termes IGN] évapotranspiration
[Termes IGN] hydrogéologie
[Termes IGN] image radar moirée
[Termes IGN] image Radarsat
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] littoral
[Termes IGN] Montréal (Québec)
[Termes IGN] surveillance géologique
[Termes IGN] urbanisationRésumé : (auteur) Monitoring ground deformations arising from groundwater dynamics in dense urban coastal terrains is crucial for the sustainable development of infrastructures in these highly populated areas. The city of Montreal, which is located in the Saint-Laurent plain in eastern Canada, with its fast-growing populations, is a unique case study for other similar cities in coastal terrains. The city undergoes high-level house foundation damages with densities reaching up to 89 repairs/km2 resulting from time-dependent ground deformations that are correlated to groundwater dynamics and evapotranspiration. Using Radarsat-2 C-Band synthetic aperture radar interferometry, we observe 3- to 5-mm ground line-of-sight displacement variations temporally outphased by few months relative to the 2-m subartesian aquifer hydraulic head variations. The deformations are observed over a 60-km2 area located in the central part of the Montreal Island in Canada, from 2008 to 2010. We observe displacements of ~1 mm/year uplift in the areas covered by 15-m-thick clay layer. These displacements are well correlated to the number of house repairs. We also observe ~2 mm/year subsidence on elevated terrains, associated with evapotranspiration. The amplitudes of the displacements observed during this two-year study are significant when integrated over the average lifetime of urban structures. We conclude that the observed ground deformations are related to the seasonal variation of hydraulic head in most of the areas of Montreal. Moreover, wetter climate forecasts over upcoming decades for this area, will accentuate groundwater level fluctuations; thus, more ground deformations are foreseen, and have to be considered in future infrastructure design standards. Numéro de notice : A2015-843 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2437368 Date de publication en ligne : 12/08/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2437368 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79187
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 12 (December 2015) . - pp 6356 - 6371[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-2015121 SL Revue Centre de documentation Revues en salle Disponible Mapillary and the power of community mapping / Peter Neubauer in Geoinformatics, vol 18 n° 8 (December 2015)
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Titre : Mapillary and the power of community mapping Type de document : Article/Communication Auteurs : Peter Neubauer, Auteur Année de publication : 2015 Article en page(s) : pp 24 - 26 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] application informatique
[Termes IGN] données localisées des bénévoles
[Termes IGN] image terrestre
[Termes IGN] prise de vue terrestre
[Termes IGN] zone urbaineRésumé : (documentaliste) Un jeune suédois a bâti une application web qui permet de collecter et traiter les images géolocalisées prises par tout un chacun pour illustrer les villes, comme Google street-view. Numéro de notice : A2015-806 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78873
in Geoinformatics > vol 18 n° 8 (December 2015) . - pp 24 - 26[article]Multi-GNSS meteorology : real-time retrieving of atmospheric water vapor from BeiDou, Galileo, GLONASS, and GPS observations / Xingxing Li in IEEE Transactions on geoscience and remote sensing, vol 53 n° 12 (December 2015)
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Titre : Multi-GNSS meteorology : real-time retrieving of atmospheric water vapor from BeiDou, Galileo, GLONASS, and GPS observations Type de document : Article/Communication Auteurs : Xingxing Li, Auteur ; Galina Dick, Auteur ; Cuixian Lu, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 6385 - 6393 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] correction troposphérique
[Termes IGN] données BeiDou
[Termes IGN] données Galileo
[Termes IGN] données GLONASS
[Termes IGN] données GPS
[Termes IGN] données météorologiques
[Termes IGN] positionnement par GNSS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] retard troposphérique zénithal
[Termes IGN] teneur intégrée en vapeur d'eau
[Termes IGN] vapeur d'eauRésumé : (auteur) The rapid development of multi-Global Navigation Satellite Systems (GNSSs, e.g., BeiDou, Galileo, GLONASS, and GPS) and the International GNSS Service (IGS) Multi-GNSS Experiment (MGEX) brings great opportunities and challenges for real-time determination of tropospheric zenith total delays (ZTDs) and integrated water vapor (IWV) to improve numerical weather prediction, particularly for nowcasting or severe weather event monitoring. In this paper, we develop a multi-GNSS model to fully exploit the potential of observations from all currently available GNSSs for enhancing real-time ZTD/IWV processing. A prototype multi-GNSS real-time ZTD/IWV monitoring system is also designed and realized at the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences (GFZ) based on the precise point positioning technique. The ZTD and IWV derived from multi-GNSS stations are carefully analyzed and compared with those from collocated Very Long Baseline Interferometry and radiosonde stations. The performance of individual GNSS is assessed, and the significant benefit of multi-GNSS for real-time water vapor retrieval is also evaluated. The statistical results show that accuracy of several millimeters with high reliability is achievable for the multi-GNSS-based real-time ZTD estimates, which corresponds to about 1- to 1.5-mm accuracy for the IWV. The ZTD/IWV with improved accuracy and reliability would be beneficial for atmospheric sounding systems, particularly for time-critical geodetic and meteorological applications. Numéro de notice : A2015-844 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2438395 En ligne : https://doi.org/10.1109/TGRS.2015.2438395 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79188
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 12 (December 2015) . - pp 6385 - 6393[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-2015121 SL Revue Centre de documentation Revues en salle Disponible Nighttime-lights-derived fossil fuel carbon dioxide emission maps and their limitations / Naizhuo Zhao in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 12 (December 2015)
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Titre : Nighttime-lights-derived fossil fuel carbon dioxide emission maps and their limitations Type de document : Article/Communication Auteurs : Naizhuo Zhao, Auteur ; Eric L. Samson, Auteur ; Nathan A. Currit, Auteur Année de publication : 2015 Article en page(s) : pp 935 - 943 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse d'image numérique
[Termes IGN] cartographie des risques
[Termes IGN] dioxyde de carbone
[Termes IGN] éclairage public
[Termes IGN] luminance lumineuse
[Termes IGN] pollution lumineuse
[Termes IGN] prise de vue nocturneRésumé : (auteur) Brightness of nighttime lights has been used as an indicator for spatial disaggregation of CO2 emission based on an assumed linear relationship between the digital number (DN) values of nighttime light imagery and the amount of CO2 emissions. However, reliability of the linear relationship of these variables has not been thoroughly examined. In this study, we find that the actual overall correlations are exponential rather than linear. More specific analyses showed that the DN values of nighttime light imagery first behaves linearly (from 3 to 50) and then exponentially (from 51 to 63), correlating to the amount of CO2 emissions. Regardless of the use of a linear or piecewise function, some featured limitations are evident as we developed the methodology. Among significant limitations, CO2 emissions were not visualized in unlit areas and a lack of variation existed in regions with the same DN values of nighttime light imagery. Lastly CO2 emissions in urban core areas were grossly under-estimated. Numéro de notice : A2015-993 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.12.935 En ligne : https://doi.org/10.14358/PERS.81.12.935 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80274
in Photogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 12 (December 2015) . - pp 935 - 943[article]Urban classification by the fusion of thermal infrared hyperspectral and visible data / Jiayi Li in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 12 (December 2015)
PermalinkAccurate and occlusion-robust multi-view stereo / Zhaokun Zhu in ISPRS Journal of photogrammetry and remote sensing, vol 109 (November 2015)
PermalinkCombining leaf physiology, hyperspectral imaging and partial least squares-regression (PLS-R) for grapevine water status assessment / Tal Rapaport in ISPRS Journal of photogrammetry and remote sensing, vol 109 (November 2015)
PermalinkMultitemporal fluctuations in L-Band Backscatter from a japanese forest / Manabu Watanabe in IEEE Transactions on geoscience and remote sensing, vol 53 n° 11 (November 2015)
PermalinkStudy of the geometry effect on land surface temperature retrieval in urban environment / Jinxin Yanga in ISPRS Journal of photogrammetry and remote sensing, vol 109 (November 2015)
PermalinkFusion of waveform LiDAR data and hyperspectral imagery for land cover classification / Hongzhou Wang in ISPRS Journal of photogrammetry and remote sensing, vol 108 (October 2015)
PermalinkLeveraging in-scene spectra for vegetation species discrimination with MESMA-MDA / Brian D. Bue in ISPRS Journal of photogrammetry and remote sensing, vol 108 (October 2015)
PermalinkMAGI : A new high-performance airborne thermal-infrared imaging spectrometer for earth science applications / Jeffrey L. Hall in IEEE Transactions on geoscience and remote sensing, vol 53 n° 10 (October 2015)
PermalinkPrecision comparison and analysis of four online free PPP services in static positioning and tropospheric delay estimation / Qiuying Guo in GPS solutions, vol 19 n° 4 (october 2015)
PermalinkSurveying a mountain highway with UAS : getting accurate results in a rough area / Matteo Luccio in Geoinformatics, vol 18 n° 7 (October - November 2015)
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