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Understanding the effects of ALS pulse density for metric retrieval across diverse forest types / Phil Wilkes in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 8 (August 2015)
[article]
Titre : Understanding the effects of ALS pulse density for metric retrieval across diverse forest types Type de document : Article/Communication Auteurs : Phil Wilkes, Auteur ; Simon D. Jones, Auteur ; Lola Suarez, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 625 - 635 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] acquisition de données
[Termes IGN] densité des points
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] forêt tropicale
[Termes IGN] hauteur des arbres
[Termes IGN] image ALOS-PALSAR
[Termes IGN] impulsion laser
[Termes IGN] indicateur de gestion forestière durable
[Termes IGN] rétrodiffusion
[Termes IGN] savane
[Termes IGN] télémétrie laser aéroportéRésumé : (auteur) Pulse density, the number of laser pulses that intercept a surface per unit area, is a key consideration when acquiring an Airborne Laser Scanning (ALS) dataset. This study compares area-based vegetation structure metrics derived from multireturn ALS simulated at six pulse densities (0.05 to 4 pl m-2) across a range of forest types: from savannah woodlands to dense rainforests. Results suggest that accurate measurement of structure metrics (canopy height, canopy cover, and vertical canopy structure) can be achieved with a pulse density of 0.5 pl m-2 across all forest types when compared to a dataset of 10 pl m-2. For pulse densities Numéro de notice : A2015-981 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.8.625 En ligne : https://doi.org/10.14358/PERS.81.8.625 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80252
in Photogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 8 (August 2015) . - pp 625 - 635[article]Using high-resolution, multispectral imagery to assess the effect of soil properties on vegetation reflectance at an abandoned feedlot / Prosper Gbolo in Geocarto international, vol 30 n° 7 - 8 (August - September 2015)
[article]
Titre : Using high-resolution, multispectral imagery to assess the effect of soil properties on vegetation reflectance at an abandoned feedlot Type de document : Article/Communication Auteurs : Prosper Gbolo, Auteur ; Phil J. Gerla, Auteur ; Gregory S. Vanderberg, Auteur Année de publication : 2015 Article en page(s) : pp 793 - 809 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] élevage
[Termes IGN] image multibande
[Termes IGN] nutriment végétal
[Termes IGN] qualité du sol
[Termes IGN] réflectance végétale
[Termes IGN] télédétection spatialeRésumé : (Auteur) Remotely sensed multispectral imagery, soils and graminoid samples from an abandoned cattle feedlot and adjacent wetlands were used to characterize plant vigour and soil nutrient distribution and evaluate the relationship between soil properties and vegetation reflectance. The feedlot lies on a sandy beach ridge, which likely mitigates the mobility of soil phosphorus. Soil phosphorus remains concentrated directly beneath the feedlot pens, where vegetation indices are low. In contrast, nitrate is transported through preferential pathways into the wetlands, where vegetation indices and plant vigour are high. Although spectral vegetation indices did not show any significant relationship with plant tissue nutrient concentration, the indices showed statistically significant relationships to some soil properties. Results of this study indicate that the abundance of nutrients in the soil does not necessarily enhance plant growth. This can limit the extent that remotely sensed vegetation indices can be used to evaluate soil nutrients concentrations. Numéro de notice : A2015-502 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2014.985746 Date de publication en ligne : 15/06/2015 En ligne : http://www.tandfonline.com/doi/full/10.1080/10106049.2014.985746 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77419
in Geocarto international > vol 30 n° 7 - 8 (August - September 2015) . - pp 793 - 809[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2015041 RAB Revue Centre de documentation En réserve L003 Disponible Development of an improved empirical model for slant delays in the troposphere (GPT2w) / Johannes Böhm in GPS solutions, vol 19 n° 3 (July 2015)
[article]
Titre : Development of an improved empirical model for slant delays in the troposphere (GPT2w) Type de document : Article/Communication Auteurs : Johannes Böhm , Auteur ; Gregor Möller, Auteur ; Michael Schindelegger, Auteur ; Grégory Pain, Auteur ; Robert Weber, Auteur Année de publication : 2015 Article en page(s) : pp 433 - 441 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] coordonnées GNSS
[Termes IGN] erreur systématique
[Termes IGN] modèle empirique
[Termes IGN] retard troposphérique
[Termes IGN] station permanente
[Termes IGN] teneur en vapeur d'eauRésumé : (Auteur) Global pressure and temperature 2 wet (GPT2w) is an empirical troposphere delay model providing the mean values plus annual and semiannual amplitudes of pressure, temperature and its lapse rate, water vapor pressure and its decrease factor, weighted mean temperature, as well as hydrostatic and wet mapping function coefficients of the Vienna mapping function 1. All climatological parameters have been derived consistently from monthly mean pressure level data of ERA-Interim fields (European Centre for Medium-Range Weather Forecasts Re-Analysis) with a horizontal resolution of 1°, and the model is suitable to calculate slant hydrostatic and wet delays down to 3° elevation at sites in the vicinity of the earth surface using the date and approximate station coordinates as input. The wet delay estimation builds upon gridded values of the water vapor pressure, the weighted mean temperature, and the water vapor decrease factor, with the latter being tuned to ray-traced zenith wet delays. Comparisons with zenith delays at 341 globally distributed global navigation satellite systems stations show that the mean bias over all stations is below 1 mm and the mean standard deviation is about 3.6 cm. The GPT2w model with the gridded input file is provided at. Numéro de notice : A2015--112 Affiliation des auteurs : ENSG+Ext (2012-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-014-0403-7 Date de publication en ligne : 26/08/2014 En ligne : https://doi.org/10.1007/s10291-014-0403-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90646
in GPS solutions > vol 19 n° 3 (July 2015) . - pp 433 - 441[article]Documents numériques
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Development of an improved ... - pdf éditeurAdobe Acrobat PDF Assessment of high-rate GPS using a single-axis shake table / Simon Häberling in Journal of geodesy, vol 89 n° 7 (July 2015)
[article]
Titre : Assessment of high-rate GPS using a single-axis shake table Type de document : Article/Communication Auteurs : Simon Häberling, Auteur ; Markus Rothacher, Auteur ; Y. Zhang, Auteur Année de publication : 2015 Article en page(s) : pp 697 - 709 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] antenne GNSS
[Termes IGN] bruit thermique
[Termes IGN] phase
[Termes IGN] réalité de terrain
[Termes IGN] récepteur GNSS
[Termes IGN] sismographeRésumé : (auteur) The developments in GNSS receiver and antenna technologies, especially the increased sampling rate up to 100 sps, open up the possibility to measure high-rate earthquake ground motions with GNSS. In this paper we focus on the GPS errors in the frequency band above 1 Hz. The dominant error sources are mainly the carrier phase jitter caused by thermal noise and the stress error caused by the dynamics, e.g. antenna motions. To generate a large set of different motions, we used a single-axis shake table, where a GNSS antenna and a strong motion seismometer were mounted with a well-known ground truth. The generated motions were recorded with three different GNSS receivers with sampling rates up to 100 sps and different receiver baseband parameters. The baseband parameters directly dictate the carrier phase jitter and the correlations between subsequent epochs. A narrow loop filter bandwidth keeps the carrier phase jitter on a low level, but has an extreme impact on the receiver response for motions above 1 Hz. The amplitudes above 3 Hz are overestimated up to 50 % or reduced by well over half. The corresponding phase errors are between 30 and 90 degrees. Compared to the GNSS receiver response, the strong motion seismometer measurements do not show any amplitude or phase variations for the frequency range from 1 to 20 Hz. Due to the large errors for dynamic GNSS measurements, it is essential to account for the baseband parameters of the GNSS receivers if high-rate GNSS is to become a valuable tool for seismic displacement measurements above 1 Hz. Fortunately, the receiver response can be corrected by an inverse filter if the baseband parameters are known. Numéro de notice : A2015-356 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0808-2 En ligne : https://doi.org/10.1007/s00190-015-0808-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76782
in Journal of geodesy > vol 89 n° 7 (July 2015) . - pp 697 - 709[article]BRDF-corrected vegetation indices confirm seasonal pattern in greening of French Guiana's forests / Emil A. Cherrington in Revue Française de Photogrammétrie et de Télédétection, n° 211 - 212 (juillet - décembre 2015)
[article]
Titre : BRDF-corrected vegetation indices confirm seasonal pattern in greening of French Guiana's forests Type de document : Article/Communication Auteurs : Emil A. Cherrington, Auteur ; Grégoire Vincent, Auteur ; Daniel Sabatier, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 3 - 9 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] forêt tropicale
[Termes IGN] Guyane (département français)
[Termes IGN] image SPOT-Végétation
[Termes IGN] image Terra-MODIS
[Termes IGN] indice de végétation
[Termes IGN] phénologie
[Termes IGN] surveillance forestière
[Termes IGN] variation saisonnièreRésumé : (auteur) Remote sensing is a useful tool set for monitoring changes in forest ecosystems, particularly remote and otherwise inaccessible tracts of tropical forest. To revisit findings of earlier satellite-based studies of phenological variation in Amazonian forests, the current study focused on the variation of vegetation indices (Vis) of French Guiana. Specifically, 12 years of VI data which had been treated for bi-directional effects were extracted from the archives of 2 particular satellite sensors: the SPOT VEGETATION instrument, and MODIS (the MODerate resolution Imaging Spectroradiometer). At the scale of the entire territory of French Guiana, as well as at 4 sites across the territory, VI data displayed strong seasonal patterns, with the dry season months having significantly higher VI estimates than the wet season months. As Vls are considered proxies for photosynthetic activity, those seasonal variations would seem to indicate leaf-Flushing across French Guiana's forests during the dry season months of September to October. Numéro de notice : A2015-900 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.52638/rfpt.2015.536 Date de publication en ligne : 30/12/2020 En ligne : https://doi.org/10.52638/rfpt.2015.536 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79555
in Revue Française de Photogrammétrie et de Télédétection > n° 211 - 212 (juillet - décembre 2015) . - pp 3 - 9[article]Cartographie du châtaignier en Alsace par imagerie satellite multi-date / Colette Meyer in Revue Française de Photogrammétrie et de Télédétection, n° 211 - 212 (juillet - décembre 2015)PermalinkSavannah woody structure modelling and mapping using multi-frequency (X-, C- and L-band) Synthetic Aperture Radar data / Laven Naidoo in ISPRS Journal of photogrammetry and remote sensing, vol 105 (July 2015)PermalinkPermalinkInvariant rules for multipolarization SAR change detection / Vincenzo Carotenuto in IEEE Transactions on geoscience and remote sensing, vol 53 n° 6 (June 2015)PermalinkValidation of canopy height profile methodology for small-footprint full-waveform airborne LiDAR data in a discontinuous canopy environment / Karolina D. Fieber in ISPRS Journal of photogrammetry and remote sensing, vol 104 (June 2015)PermalinkEliminating diffraction effects during multi-frequency correction in global navigation satellite systems / M.V. Tinin in Journal of geodesy, vol 89 n° 5 (May 2015)PermalinkInterferometric phase image estimation via sparse coding in the complex domain / Hao Hongxing in IEEE Transactions on geoscience and remote sensing, vol 53 n° 5 (mai 2015)PermalinkIonospheric effects in uncalibrated phase delay estimation and ambiguity-fixed PPP based on raw observable model / Shengfeng Gu in Journal of geodesy, vol 89 n° 5 (May 2015)PermalinkThe soil moisture active passive validation experiment 2012 (SMAPVEX12): Prelaunch calibration and validation of the SMAP Soil moisture algorithms / Heather McNairn in IEEE Transactions on geoscience and remote sensing, vol 53 n° 5 (mai 2015)PermalinkTsunami-wave parameter estimation using GNSS-based sea surface height measurement / Kegen Yu in IEEE Transactions on geoscience and remote sensing, vol 53 n° 5 (mai 2015)Permalink