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Effect of corn on C-an L-band radar backscatter: a correction method for soil moisture retrieval / A. Joseph in Remote sensing of environment, vol 114 n° 11 (15/11/2010)
[article]
Titre : Effect of corn on C-an L-band radar backscatter: a correction method for soil moisture retrieval Type de document : Article/Communication Auteurs : A. Joseph, Auteur ; R. Van Der Velde, Auteur ; P. O'neill, Auteur ; R. Lang, Auteur ; T. Gish, Auteur Année de publication : 2010 Article en page(s) : pp 2417 - 2430 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] angle d'incidence
[Termes IGN] bande C
[Termes IGN] bande L
[Termes IGN] biomasse
[Termes IGN] humidité du sol
[Termes IGN] maïs (céréale)
[Termes IGN] polarimétrie radar
[Termes IGN] rétrodiffusion
[Termes IGN] teneur en eau de la végétationRésumé : (Auteur) This paper discusses the effects of vegetation on C- (4.75 GHz) and L- (1.6 GHz) band backscattering (Ó) measured throughout a growth cycle at incidence angles of 15, 35 and 55°. The utilized Ó data set was collected by a truck mounted scatterometer over a corn field and is supported by a comprehensive set of ground measurements, including soil moisture and vegetation biomass. Comparison of Ó measurement against simulations by the Integral Equation Method (IEM) surface scattering model (Fung et al., 1992) shows that the Ó measurements are dominated either by an attenuated soil return or by scattering from vegetation depending on the antenna configuration and growth stage. Further, the measured Ó is found to be sensitive to soil moisture even at peak biomass and large incidence angles, which is attributed to scattering along the soil-vegetation pathway. For the simulation of C-band Ó and the retrieval of soil moisture two methods have been applied, which are the semi-empirical water cloud model (Attema & Ulaby, 1978) and a novel method. This alternative method uses the empirical relationships between the vegetation water content (W) and the ratio of the bare soil and the measured Ó to correct for vegetation. It is found that this alternative method is superior in reproducing the measured Ó as well as retrieving soil moisture. The highest retrieval accuracies are obtained at a 35° incidence angle leading to RMSD's of 0.044 and 0.037 m3 m- 3 for the HH and VV-polarization, respectively. In addition, the sensitivity of these soil moisture retrievals to W and surface roughness parameter uncertainties is investigated. Numéro de notice : A2010-400 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2010.05.017 En ligne : https://doi.org/10.1016/j.rse.2010.05.017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30593
in Remote sensing of environment > vol 114 n° 11 (15/11/2010) . - pp 2417 - 2430[article]Snow permitivity retrieval inversion algorithm for estimating snow wetness / G. Singh in Geocarto international, vol 25 n° 3 (June 2010)
[article]
Titre : Snow permitivity retrieval inversion algorithm for estimating snow wetness Type de document : Article/Communication Auteurs : G. Singh, Auteur ; G. Venkataraman, Auteur Année de publication : 2010 Article en page(s) : pp 187 - 212 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] constante diélectrique
[Termes IGN] image Envisat-ASAR
[Termes IGN] modèle d'inversion
[Termes IGN] neige
[Termes IGN] prévention des risques
[Termes IGN] rétrodiffusion
[Termes IGN] surveillance hydrologique
[Termes IGN] traitement d'imageRésumé : (Auteur) The environmental satellite (ENVISAT) advanced synthetic aperture radar (ASAR) offers the opportunity for monitoring snow parameters with dual polarization and multi-incidence angle. Snow wetness is an important index for indicating snow avalanche, snowmelt runoff modelling, water supply for irrigation and hydropower stations, weather forecasts and understanding climate change. We used a first-order scattering model that includes both volume and air/snow surface scattering based on a developed inversion model to estimate snow dielectric constant, which can be further related for estimating snow wetness. Comparison with field measurement showed that the correlation coefficient for snow permittivity estimated from ASAR data was observed to be 0.8 at 95% confidence interval and model bias was observed as 2.42% by volume at 95% confidence interval. The comparison of ASAR-derived snow permittivity with ground measurements shows the average absolute error 2.5%. The snow wetness range varies from 0 to 15% by volume. Numéro de notice : A2010-266 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106040903486130 Date de publication en ligne : 18/02/2010 En ligne : https://doi.org/10.1080/10106040903486130 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30460
in Geocarto international > vol 25 n° 3 (June 2010) . - pp 187 - 212[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 059-2010031 RAB Revue Centre de documentation En réserve L003 Disponible Discrimination of agricultural crops in a tropical semi-arid region of Brazil based on L-band polarimetric airborne SAR data / W. Silva in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)
[article]
Titre : Discrimination of agricultural crops in a tropical semi-arid region of Brazil based on L-band polarimetric airborne SAR data Type de document : Article/Communication Auteurs : W. Silva, Auteur ; B. Rudorff, Auteur ; A. Formaggio, Auteur ; W. Paradella, Auteur ; J. Mura, Auteur Année de publication : 2009 Article en page(s) : pp 458 - 463 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] Amérique tropicale
[Termes IGN] analyse discriminante
[Termes IGN] Bahia (Brésil)
[Termes IGN] bande L
[Termes IGN] classificateur
[Termes IGN] Coffea (genre)
[Termes IGN] cultures
[Termes IGN] Gossypium (genre)
[Termes IGN] image aérienne
[Termes IGN] image radar moirée
[Termes IGN] milieu tropical
[Termes IGN] polarimétrie radar
[Termes IGN] polarisation
[Termes IGN] prise en compte du contexte
[Termes IGN] rétrodiffusion
[Termes IGN] zone intertropicale
[Termes IGN] zone semi-arideRésumé : (Auteur) Recent articles are indicating that polarimetric data provide significantly more information than conventional or multi-polarized images, particularly due to the additional phase information. The objective of this paper is to evaluate the multi-polarized and fully polarimetric L-band airborne SAR-R99B data, in terms of their capability to distinguish among different agricultural crops in the western part of Bahia State, Brazil. Emphasis was given to coffee, cotton and pasture crops which were at well developed growing stages. Discrimination among crops was carried out using graphical analysis of mean backscatter values. Crop classification was performed for single and multiple polarizations, and fully polarimetric images with a classifier that uses the contextual Iterated Conditional Modes–ICM algorithm. The investigation confirmed the potential of L-band multi-polarized and polarimetric airborne SAR-R99B data to distinguish and classify agricultural crops in the tropical condition of the test-site. In addition, it clearly indicated the gradual and considerable improvement that was achieved going from single to three polarizations and from multi-polarized to fully polarimetric images. Copyright ISPRS Numéro de notice : A2009-398 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2008.07.005 En ligne : https://doi.org/10.1016/j.isprsjprs.2008.07.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30029
in ISPRS Journal of photogrammetry and remote sensing > vol 64 n° 5 (September - October 2009) . - pp 458 - 463[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-09051 SL Revue Centre de documentation Revues en salle Disponible Potentiality of feed-forward neural networks for classifying dark formations to oil spills and look-alikes / Konstantinos Topouzelis in Geocarto international, vol 24 n° 3 (June - July 2009)
[article]
Titre : Potentiality of feed-forward neural networks for classifying dark formations to oil spills and look-alikes Type de document : Article/Communication Auteurs : Konstantinos Topouzelis, Auteur ; V. Karathanassi, Auteur ; P. Pavlaskis, Auteur ; D. Rokos, Auteur Année de publication : 2009 Article en page(s) : pp 179 - 191 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] classification par réseau neuronal
[Termes IGN] détection
[Termes IGN] fonction de base radiale
[Termes IGN] hydrocarbure
[Termes IGN] image radar
[Termes IGN] marée noire
[Termes IGN] Perceptron multicouche
[Termes IGN] pollution des mers
[Termes IGN] rétrodiffusionRésumé : (Auteur) Radar backscatter values from oil spills are very similar to backscatter values from very calm sea areas and other ocean phenomena. Several studies aiming at oil spill detection have been conducted. Most of these studies rely on the detection of dark areas, which have high Bayesian probability of being oil spills. The drawback of these methods is a complex process, mainly because non-linearly separable datasets are introduced in statistically based decisions. The use of neural networks (NNs) in remote sensing has increased significantly, as NNs can simultaneously handle non-linear data of a multidimensional input space. In this article, we investigate the ability of two commonly used feed-forward NN models: multilayer perceptron (MLP) and radial basis function (RBF) networks, to classify dark formations in oil spills and look-alike phenomena. The appropriate training algorithm, type and architecture of the optimum network are subjects of research. Inputs to the networks are the original synthetic aperture radar image and other images derived from it. MLP networks are recognized as more suitable for oil spill detection. Numéro de notice : A2009-186 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106040802488526 Date de publication en ligne : 19/05/2009 En ligne : https://doi.org/10.1080/10106040802488526 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29816
in Geocarto international > vol 24 n° 3 (June - July 2009) . - pp 179 - 191[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 059-09031 RAB Revue Centre de documentation En réserve L003 Disponible Radiometric Calibration of LIDAR Intensity With Commercially Available Reference Targets / S. Kaasalainen in IEEE Transactions on geoscience and remote sensing, vol 47 n° 2 (February 2009)
[article]
Titre : Radiometric Calibration of LIDAR Intensity With Commercially Available Reference Targets Type de document : Article/Communication Auteurs : S. Kaasalainen, Auteur ; Juha Hyyppä, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 588 - 598 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] détection de cible
[Termes IGN] données lidar
[Termes IGN] étalonnage radiométrique
[Termes IGN] intensité lumineuse
[Termes IGN] Lidar
[Termes IGN] luminance lumineuse
[Termes IGN] objet géographique ponctuel
[Termes IGN] réflectance
[Termes IGN] rétrodiffusionRésumé : (Auteur) We present a new approach for radiometric calibration of light detection and ranging (LIDAR) intensity data and demonstrate an application of this method to natural targets. The method is based on 1) using commercially available sand and gravel as reference targets and 2) the calibration of these reference targets in the laboratory conditions to know their backscatter properties. We have investigated the target properties crucial for accurate and consistent reflectance calibration and present a set of ideal targets easily available for calibration purposes. The first results from LIDAR-based brightness measurement of grass and sand show that the gravel-based calibration approach works in practice, is cost effective, and produces statistically meaningful results: Comparison of results from two separate airborne laser scanning campaigns shows that the relative calibration produces repeatable reflectance values. Copyright IEEE Numéro de notice : A2009-023 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2008.2003351 En ligne : https://doi.org/10.1109/TGRS.2008.2003351 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29653
in IEEE Transactions on geoscience and remote sensing > vol 47 n° 2 (February 2009) . - pp 588 - 598[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-09021 RAB Revue Centre de documentation En réserve L003 Disponible Full-waveform topographic lidar: State-of-the-art / Frédéric Bretar in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 1 (January - February 2009)PermalinkRetrieval of surface roughness using multi-polarized Envisat-1 ASAR data / H.s Srivastava in Geocarto international, vol 23 n° 1 (February - March 2008)PermalinkGaussian decomposition and calibration of a novel small-footprint full-waveform digitising airborne laser scanner / W. Wagner in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 2 (April 2006)PermalinkEvaluation of a rough soil surface description with ASAR-ENVISAT radar data / Mehrez Zribi in Remote sensing of environment, vol 95 n° 1 (15/03/2005)PermalinkDetection of stationary foliage-obscured targets by polarimetric millimeter-wave radar / A.Y. Nashashibi in IEEE Transactions on geoscience and remote sensing, vol 43 n° 1 (January 2005)PermalinkBidirectional reflectance of Earth targets: evaluation of analytical models using a large set of spaceborne measurements with emphasis on the Hot Spot / F. Maignan in Remote sensing of environment, vol 90 n° 2 (30/03/2004)PermalinkAssessing the potential of space-borne C-band SAR data for spatial soil moisture information over a large area / S.A. Romshoo in Geocarto international, vol 19 n° 1 (March - May 2004)PermalinkThe use of fully polarimetric information for the fuzzy neural classification of SAR images / C.T. Chen in IEEE Transactions on geoscience and remote sensing, vol 41 n° 9 (September 2003)PermalinkMultitemporal repeat-pass SAR interferometry of boreal forests / J. Askne in IEEE Transactions on geoscience and remote sensing, vol 41 n° 7 (July 2003)PermalinkRemote sensing techniques to assess water quality / J.C. Ritchie in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 6 (June 2003)PermalinkPotential of reflected intensity of airborne laser scanning systems in roadway features identification / Kiyun Yu in Geomatica, vol 56 n° 4 (December 2002)PermalinkOn the retrieving of forest stem volume from VHF SAR data: observation and modeling / P. Melon in IEEE Transactions on geoscience and remote sensing, vol 39 n° 11 (November 2001)PermalinkTraitement des images de RSO [Radar à Synthèse d'0uverture] / Henri Maître (2001)PermalinkAnalyse des paysages côtiers par signatures radar : expérimentation GlobeSAR / G. Bonnaffoux in Photo interprétation, vol 36 n° 2-3 (Mai 1998)PermalinkDevelopment of models for monitoring the urban environment using radar remote sensing / Catherine Ticehurst (1998)PermalinkEtude de la perception de la morphologie en forêt tropicale humide dense (Guyane française) à partir d'images radar SAR-ERS 1 / Michaël Tonon (1993)PermalinkPrincipes d'imagerie radar / Jean-François Dallemand (1991)PermalinkA numerical model for radar backscatter from a lossy inhomogeneous layer / H.T. Chuah in International Journal of Remote Sensing IJRS, vol 11 n° 4 (April 1990)PermalinkRadar backscatter measurements over saline ice / S. Gogineni in International Journal of Remote Sensing IJRS, vol 11 n° 4 (April 1990)PermalinkThe slightly-rough facet model in radar imaging of the ocean surface / J.C. West in International Journal of Remote Sensing IJRS, vol 11 n° 4 (April 1990)Permalink