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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]Non-invasive forest litter characterization using full-wave inversion of microwave radar data / Frédéric André in IEEE Transactions on geoscience and remote sensing, vol 53 n° 2 (February 2015)
[article]
Titre : Non-invasive forest litter characterization using full-wave inversion of microwave radar data Type de document : Article/Communication Auteurs : Frédéric André, Auteur ; Mathieu Jonard, Auteur ; Sébastien Lambot, Auteur Année de publication : 2015 Article en page(s) : pp 828 - 840 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] caractérisation
[Termes IGN] déchet organique
[Termes IGN] Fagus (genre)
[Termes IGN] forêt
[Termes IGN] forme d'onde pleine
[Termes IGN] humidité du sol
[Termes IGN] image radar
[Termes IGN] litière
[Termes IGN] radar pénétrant GPR
[Termes IGN] rétrodiffusion
[Termes IGN] sol forestier
[Termes IGN] télédétection en hyperfréquenceRésumé : (Auteur) Litter is acknowledged to affect microwave remote sensing data over forests, and accurate quantification of litter radiative properties is essential for proper retrieval of forest soil water content and forest canopy biophysical characteristics from satellite or airborne sensors. Furthermore, detailed characterization of forest soil organic horizons is of paramount importance for ecological studies and for carbon cycle and global changerelated studies. Ultrawideband ground-penetrating radar (GPR) data acquired above beech forest litter were used to analyze the effects of litter on the backscattering and investigate the ability of GPR to quantitatively characterize the properties of the forest floor. Radar measurements were performed over different litter configurations (i.e., single layers of recently fallen litter (OL) or of fragmented litter (OF), and combined OL-OF layers) and thicknesses. Radar data were processed through full-wave inversion. Over the considered frequency range (0.8-4.0 GHz), attenuation of the radar signal increased as both frequency and litter thickness increase, due to scattering and dielectric losses. These effects were accounted for in the radar model through frequency dependence of litter apparent electrical conductivity. Good agreement (RMSE = 9.5 × 10-3 m) was observed between estimated and measured litter thicknesses. Radar data inversions provided reliable estimates of litter electromagnetic properties, with relative dielectric permittivity values around 1.2 and 3.9 for OL and OF litters, respectively, and corresponding values of 0.032 and 0.080 Sm-1 for litter apparent electrical conductivity at 4.0 GHz. These results show great promise for the use of GPR for noninvasive characterization of forest litter. Numéro de notice : A2015-102 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2014.2328776 En ligne : https://doi.org/10.1109/TGRS.2014.2328776 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75620
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 2 (February 2015) . - pp 828 - 840[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015021 RAB Revue Centre de documentation En réserve L003 Disponible Modelling electrical conductivity of soil from backscattering coefficient of microwave remotely sensed data using artificial neural network / Walaiporn Phonphan in Geocarto international, vol 29 n° 7 - 8 (November - December 2014)
[article]
Titre : Modelling electrical conductivity of soil from backscattering coefficient of microwave remotely sensed data using artificial neural network Type de document : Article/Communication Auteurs : Walaiporn Phonphan, Auteur ; Nitin Kumar Tripathi, Auteur ; Taravudh Tipdecho, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 842 - 859 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] image ALOS-PALSAR
[Termes IGN] micro-onde
[Termes IGN] rétrodiffusion
[Termes IGN] salinitéRésumé : (Auteur) Soil salinity is one of the main agricultural problems which expand to larger areas. Soil scientists categorize salinity level by electrical conductivity (EC) measurement. However, field measurements of EC require extensive time, cost and experiences. Remote sensing is one suitable option to investigate and collect spatial data in larger areas. Many researches estimated soil moisture through microwave, but there are fewer studies which mentioned about direct relationship between EC and backscattering coefficient (BC). Thus, this study aims to propose the estimation of EC directly from BC of microwave. The relationship between EC obtained from field survey and BC from microwave is non-linear, artificial neural network (ANN) is one technique proposed in this study to figure out EC and BC relationship. ANN uses multilayer of interconnected processing resulting in EC value with high accuracy which is acceptable. For this reason, ANN model can be successfully utilized as an effective tool for EC estimation from microwave. Numéro de notice : A2014-469 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2013.868040 En ligne : https://doi.org/10.1080/10106049.2013.868040 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74046
in Geocarto international > vol 29 n° 7 - 8 (November - December 2014) . - pp 842 - 859[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2014041 RAB Revue Centre de documentation En réserve L003 Disponible Measurements of forest biomass change using P-Band synthetic aperture radar backscatter / Gustaf Sandberg in IEEE Transactions on geoscience and remote sensing, vol 52 n° 10 tome 1 (October 2014)
[article]
Titre : Measurements of forest biomass change using P-Band synthetic aperture radar backscatter Type de document : Article/Communication Auteurs : Gustaf Sandberg, Auteur ; Lars M.H. Ulander, Auteur ; Jörgen Wallerman, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 6047 - 6061 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] bande P
[Termes IGN] biomasse
[Termes IGN] détection de changement
[Termes IGN] données laser
[Termes IGN] forêt boréale
[Termes IGN] radar à antenne synthétique
[Termes IGN] rétrodiffusion
[Termes IGN] Suède
[Termes IGN] télédétection en hyperfréquenceRésumé : (Auteur) Methods to estimate forest biomass change have been investigated using experimental P-band synthetic aperture radar (SAR) data from the recent airborne campaigns BioSAR 2007 and BioSAR 2010 conducted over a hemiboreal test site in southern Sweden. Regression models based on backscatter change were developed using reference biomass change maps derived from high-density laser scanning data. Different regression models were developed for linear, square root, and logarithmic biomass change scales. The models were compared to the change maps based on laser data using twofold cross-validation, and estimation errors were evaluated using six 80 m by 80 m plots with detailed in situ measurements. The results indicate that the root-mean-square error of biomass change estimates based on P-band SAR backscatter data is about 15% or 20 t/ha. This suggests that not only clear-cuts but also growth and thinning can be measured. Simulations were performed in order to evaluate the possibility of using a spaceborne P-band SAR for measurements of forest biomass change. The simulations show that, with 64 equivalent number of looks (ENL) and a 50% change in biomass, it is possible to correctly indicate whether the forest has gained or lost biomass. Similarly, for a biomass loss of more than 75%, a correct indication of the sign of biomass change can be achieved with only 8 ENL. Numéro de notice : A2014-479 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2294684 En ligne : https://doi.org/10.1109/TGRS.2013.2294684 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74060
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 10 tome 1 (October 2014) . - pp 6047 - 6061[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014101A RAB Revue Centre de documentation En réserve L003 Disponible On the SAR backscatter of burned forests: a model-based study in C-Band, over burned pine canopies full text / Vasileios kalogirou in IEEE Transactions on geoscience and remote sensing, vol 52 n° 10 tome 1 (October 2014)
[article]
Titre : On the SAR backscatter of burned forests: a model-based study in C-Band, over burned pine canopies full text Type de document : Article/Communication Auteurs : Vasileios kalogirou, Auteur ; P. Ferrazzoli, Auteur ; Andrea Della Vecchia, Auteur ; Michael Foumelis, Auteur Année de publication : 2014 Article en page(s) : pp 6205 - 6215 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] forêt
[Termes IGN] Grèce
[Termes IGN] image C-SAR
[Termes IGN] impact sur l'environnement
[Termes IGN] incendie de forêt
[Termes IGN] modèle de transfert radiatif
[Termes IGN] rétrodiffusionRésumé : (Auteur) A discrete scattering model, based on the radiative-transfer theory, is used to simulate the backscattering of burned pine canopies at C-band. The model is first parameterized either with direct field measurements on a selected burned area in Greece or with proper estimations of the required variables, for which direct measurements were not possible. The simulated backscatter at VV polarization was compared against European Remote Sensing 2 (ERS-2) observations. The comparison was based on the observed backscattering of nine burned plots, during four different postfire acquisitions (n=36). In general, the model provides satisfying estimations of the backscattering with a root-mean-square error of 1.01 dB. The copolar signal for both HH and VV showed a mild decrease with increasing fire impacts and was considerably affected by the incidence angle. From the experiments performed in the simulated environment, it is concluded that the SAR copolar (C-band) backscatter varies with respect to certain fire impact levels. Other important acquisition- or stand-dependent variables (such as incidence angle and snag age) were also found to impact the relationship between backscatter and fire impacts. Finally, the backscattering variability on increasing volumetric soil moisture (VSM) and snag moisture was examined. The increase of VSM from 20% to 30% amplified the signal in both copolarized bands by 1.2-1.5 dB. This amplification was more apparent on VV polarization than in HH polarization. Instead, the HH signal proved to be more sensitive on the increase of snag moisture, which was tested under a stable dry soil. Numéro de notice : A2014-480 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2295594 En ligne : https://doi.org/10.1109/TGRS.2013.2295594 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74061
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 10 tome 1 (October 2014) . - pp 6205 - 6215[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014101A RAB Revue Centre de documentation En réserve L003 Disponible A novel rapid SAR simulator based on equivalent scatterers for three-dimensional forest canopies / Tao Zeng in IEEE Transactions on geoscience and remote sensing, vol 52 n° 9 Tome 1 (September 2014)PermalinkBackscattering of individual LiDAR pulses from forest canopies explained by photogrammetrically derived vegetation structure / Ilkka Korpela in ISPRS Journal of photogrammetry and remote sensing, vol 83 (September 2013)PermalinkRetrieval of tropical forest biomass information from ALOS PALSAR data / Mahmudur Rahman in Geocarto international, vol 28 n° 5-6 (August - October 2013)PermalinkPolarization scatterer feature metric space / William L. Cameron in IEEE Transactions on geoscience and remote sensing, vol 51 n° 6 Tome 2 (June 2013)PermalinkSoil moisture estimation under low vegetation cover using a multi-angular polarimetric decomposition / Thomas Jaghuber in IEEE Transactions on geoscience and remote sensing, vol 51 n° 4 Tome 2 (April 2013)PermalinkA proposed framework to unmix scattering mechanisms of polarimetric radar images using very high resolution optical images / Sébastien Giordano in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol I-7 (2012)PermalinkTesting a near-infrared Lidar mounted with a large incidence angle to monitor the water level of turbid reservoirs / S. Tamari in ISPRS Journal of photogrammetry and remote sensing, vol 66 n° 6 supplement (December 2011)PermalinkRadar backscatter mapping using TerraSAR-X / P. Rizzoli in IEEE Transactions on geoscience and remote sensing, vol 49 n° 10 Tome 1 (October 2011)PermalinkEffect 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)PermalinkFriendly reflections: monitoring water level with GNSS / A. Egido in GPS world, vol 21 n° 9 (September 2010)PermalinkSnow permitivity retrieval inversion algorithm for estimating snow wetness / G. Singh in Geocarto international, vol 25 n° 3 (June 2010)PermalinkA case study of using Raman lidar measurements in high-accuracy GPS applications / Pierre Bosser in Journal of geodesy, vol 84 n° 4 (April 2010)PermalinkDiscrimination 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)PermalinkPotentiality 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)PermalinkRadiometric 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)PermalinkFull-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)PermalinkDéveloppement et validation d'une méthode de calcul GPS intégrant des mesures de profils de vapeur d'eau en visée multi-angulaire pour l'altimétrie de haute précision / Pierre Bosser (2008)PermalinkEléments de physique pour l'imagerie aérienne et spatiale et la géodésie [diaporama pour le master PPMD] / Michel Kasser (2008)PermalinkLidar et applications en géophysique externe / P.H. Flamant in Revue Française de Photogrammétrie et de Télédétection, n° 186 (Juin 2007)Permalink