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Hyperspectral vegetation indices and novel algorithms for predicting green LAI of crop canopies: modelling and validation in the context of precision agriculture / D. Haboudane in Remote sensing of environment, vol 90 n° 3 (15/04/2004)
[article]
Titre : Hyperspectral vegetation indices and novel algorithms for predicting green LAI of crop canopies: modelling and validation in the context of precision agriculture Type de document : Article/Communication Auteurs : D. Haboudane, Auteur ; J.R. Miller, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 337 - 352 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] agriculture de précision
[Termes IGN] analyse comparative
[Termes IGN] blé (céréale)
[Termes IGN] chlorophylle
[Termes IGN] cultures
[Termes IGN] données de terrain
[Termes IGN] Glycine max
[Termes IGN] Green Leaf Area Index
[Termes IGN] image CASI
[Termes IGN] image hyperspectrale
[Termes IGN] indice de végétation
[Termes IGN] maïs (céréale)
[Termes IGN] modèle de transfert radiatif
[Termes IGN] prévision
[Termes IGN] réflectance végétaleRésumé : (Auteur) A growing number of studies have focused on evaluating spectral indices in terms of their sensitivity to vegetation biophysical parameters, as well as to external factors affecting canopy reflectance. In this context, leaf and canopy radiative transfer models are valuable for modeling and understanding the behavior of such indices. In the present work, PROSPECT and SAILH models have been used to simulate a wide range of crop canopy reflectances in an attempt to study the sensitivity of a set of vegetation indices to green leaf area index (LAI), and to modify some of them in order to enhance their responsivity to LAI variations. The aim of the paper was to present a method for minimizing the effect of leaf chlorophyll content on the prediction of green LAI, and to develop new algorithms that adequately predict the LAI of crop canopies. Analyses based on both simulated and real hyperspectral data were carried out to compare performances of existing vegetation indices (Normalized Difference Vegetation Index [NDVI], Renormalized Difference Vegetation Index [RDVI], Modified Simple Ratio [MSR], Soil-Adjusted Vegetation Index [SAVI], Soil and Atmospherically Resistant Vegetation Index [SARVI], MSAVI, Triangular Vegetation Index [TVI], and Modified Chlorophyll Absorption Ratio Index [MCARI]) and to design new ones (MTVII, MCARII, MTV12, and MCAR12) that are both less sensitive to chlorophyll content variations and linearly related to green LAI. Thorough analyses showed that the above existing vegetation indices were either sensitive to chlorophyll concentration changes or affected by saturation at high LAI levels. Conversely, two of the spectral indices developed as a part of this study, a modified triangular vegetation index (MTV12) and a modified chlorophyll absorption ratio index (MCAR12), proved to be the best predictors of green LAI. Related predictive algorithms were tested on CASI (Compact Airborne Spectrographic Imager) hyperspectral images and, then, validated using ground truth measurements. The latter were collected simultaneously with image acquisition for different crop types (soybean, corn, and wheat), at different growth stages, and under various fertilization treatments. Prediction power analysis of proposed algorithms based on MCAR12 and MTV12 resulted in agreements between modeled and ground measurement of non-destructive LAI, with coefficients of determination (r) being 0.98 for soybean, 0.89 for com, and 0.74 for wheat. The corresponding RMSE for LAI were estimated at 0.28, 0.46, and 0.85, respectively. Numéro de notice : A2004-201 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.12.013 En ligne : https://doi.org/10.1016/j.rse.2003.12.013 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26728
in Remote sensing of environment > vol 90 n° 3 (15/04/2004) . - pp 337 - 352[article]Hillshading of terrain using layer tints with aspect-variant luminosity / Patrick Kennelly in Cartography and Geographic Information Science, vol 31 n° 2 (April 2004)
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Titre : Hillshading of terrain using layer tints with aspect-variant luminosity Type de document : Article/Communication Auteurs : Patrick Kennelly, Auteur ; A.J. Kimerling, Auteur Année de publication : 2004 Article en page(s) : pp 67 - 77 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie numérique
[Termes IGN] éclairement lumineux
[Termes IGN] estompage
[Termes IGN] luminance lumineuse
[Termes IGN] transformation intensité-teinte-saturationRésumé : (Auteur) Hillshading provides a rendering of topographic surfaces by assigning brightness to surface elements based on the orientation of these elements and a selected direction of illumination. Users easily visualize many topographic features, but some areas lack detail, as one shade of gray does not define a unique surface orientation. We clarify some of this ambiguity by varying the color of layer tints with aspect direction. We use the CIELAB [commission internationale de l'éclairage] color model to quantify color specifications and map variations in luminosity onto slices of the Hue-Saturation-Value (HSV) color model. Traditionally, cartographers assign an aspect-invariant color (or colors) based on H and S and vary V with the hillshading values. In our research, we assign aspect-variant H and V values in close proximity in HSV color space. We use values of luminosity and saturation from the CIELAB and HSV color models to select colors that are least saturated, most saturated, least luminous, and most luminous to represent the northwest, southeast, southwest, and northeast directions, respectively. We then vary V in the traditional manner with hillshading from the northwest. Topographic details not apparent in the original hillshaded mas are highlighted with this technique. Numéro de notice : A2004-340 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1559/1523040041649416 En ligne : https://doi.org/10.1559/1523040041649416 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26867
in Cartography and Geographic Information Science > vol 31 n° 2 (April 2004) . - pp 67 - 77[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-04021 RAB Revue Centre de documentation En réserve L003 Disponible Quand la photogrammétrie sort des sentiers battus / Françoise de Blomac in SIG la lettre, n° 56 (avril 2004)
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Titre : Quand la photogrammétrie sort des sentiers battus Type de document : Article/Communication Auteurs : Françoise de Blomac, Auteur Année de publication : 2004 Article en page(s) : pp 10 - 11 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Photogrammétrie
[Termes IGN] caméra numérique
[Termes IGN] conception assistée par ordinateur
[Termes IGN] logiciel de simulation
[Termes IGN] photogrammétrie
[Termes IGN] photogrammétrie métrologique
[Termes IGN] photogrammétrie numérique
[Termes IGN] rayonnement gamma
[Termes IGN] réalité virtuelleRésumé : (Auteur) En plaçant leur forum de photogrammétrie sous l'égide de la réalité virtuelle, les élèves de l'Ecole Nationale des Sciences Géographiques (ENSG) ont volontairement choisi de s'éloigner un peu des thématiques géographiques traditionnelles. Même si les exposants étaient là pour rappeler que la photogrammétrie est affaire de caméras, de logiciels de traitement et de visualisation, les conférences ont "pris le large" pour aborder des sujets comme l'industrie ou la simulation d'éclairage. Numéro de notice : A2004-177 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26704
in SIG la lettre > n° 56 (avril 2004) . - pp 10 - 11[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 286-04041 RAB Revue Centre de documentation En réserve L003 Disponible The determination of the atmospheric optical thickness over western Europe using SeaWiFS imagery / A.A. Kokhanovsky in IEEE Transactions on geoscience and remote sensing, vol 42 n° 4 (April 2004)
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Titre : The determination of the atmospheric optical thickness over western Europe using SeaWiFS imagery Type de document : Article/Communication Auteurs : A.A. Kokhanovsky, Auteur ; W. Hoyningen-Huene, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 824 - 832 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] aérosol
[Termes IGN] atmosphère terrestre
[Termes IGN] effet atmosphérique
[Termes IGN] épaisseur optique
[Termes IGN] Europe occidentale
[Termes IGN] image optique
[Termes IGN] image Seawifs
[Termes IGN] nuage
[Termes IGN] transfert radiatifRésumé : (Auteur) The first results obtained from the aerosol-cloud retrieval algorithm (developed at the University of Bremen) are presented. The algorithm enables the observation of the regional characteristics of aerosol and cloud optical thickness both over land and ocean surfaces. The aerosol and cloud optical thickness over Western Europe is derived from the high-resolution SeaWiFS data for October 11, 2001 (11:30 UTC). The most probable value of the aerosol optical thickness was found to be equal approximately 0.25. The frequency distributions of the aerosol and cloud optical thickness are skewed and have long tails for larger optical thickness. It was found that retrieved values of the aerosol optical thickness at wavelengths 0.412 and 0.440 um are close to those measured by five ground-based instruments placed at different locations. The problems related to the retrieval of the atmospheric optical thickness from space are discussed. Numéro de notice : A2004-186 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2003.819880 En ligne : https://doi.org/10.1109/TGRS.2003.819880 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26713
in IEEE Transactions on geoscience and remote sensing > vol 42 n° 4 (April 2004) . - pp 824 - 832[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-04041 RAB Revue Centre de documentation En réserve L003 Disponible Bidirectional 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)
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Titre : Bidirectional reflectance of Earth targets: evaluation of analytical models using a large set of spaceborne measurements with emphasis on the Hot Spot Type de document : Article/Communication Auteurs : F. Maignan, Auteur ; François-Marie Bréon, Auteur ; R. Lacaze, Auteur Année de publication : 2004 Article en page(s) : pp 210 - 220 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Rayonnement électromagnétique
[Termes IGN] albedo
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] image ADEOS-POLDER
[Termes IGN] réflectance
[Termes IGN] rétrodiffusion
[Termes IGN] tâche claire
[Termes IGN] transfert radiatifRésumé : (Auteur) Multidirectional observation from the spacebome POLDER (Polarization and Directionality of the Earth Reflectance) instrument makes it possible to measure the bidirectional reflectance of a large variety of Earth targets. A careful selection of cloud-free measurements with a large directional coverage lead to about 22,000 sets of measured Bidirectional Reflectance Distribution Functions (BRDFs). This data set is used to evaluate the ability of analytical models to reproduce the observed directional signatures. Among those evaluated, the best models appear to be the three-parameter linear Ross-Li model, and the nonlinear Rahman-Pinty-Verstraete (RPV) model. On the other hand, all models fail to accurately reproduce the sharp reflectance increase (hot spot) close to the backscattering direction. Based on physical considerations, we suggest a modification of the Ross-Li model, without adding a free parameter, to account for the complex radiative transfer within the canopy that leads to the hot spot signature. The modified linear model performs better than all others, including the RPV nonlinear model. Although the correction modifies the retrieved directional signature parameters, it does not change significantly the surface albedo estimates. Numéro de notice : A2004-142 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.12.006 En ligne : https://doi.org/10.1016/j.rse.2003.12.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26669
in Remote sensing of environment > vol 90 n° 2 (30/03/2004) . - pp 210 - 220[article]Cloud screening in IRS-P4 OCM satellite data: potential of spatial coherence method in the absence of thermal channel information / S.K. Nair in Remote sensing of environment, vol 90 n° 2 (30/03/2004)PermalinkComparison of land surface emissivity and radiometric temperature derived from MODIS and ASTER sensors / F. Jacob in Remote sensing of environment, vol 90 n° 2 (30/03/2004)PermalinkTopographic information of sand dunes as extracted from shading effects using Landsat images / N. Levin in Remote sensing of environment, vol 90 n° 2 (30/03/2004)PermalinkSmoothing vegetation spectra with wavelets / K.S. Schmidt in International Journal of Remote Sensing IJRS, vol 25 n° 6 (March 2004)PermalinkAirborne measurement of hot spot reflectance signatures / F. Camacho-De Coca in Remote sensing of environment, vol 90 n° 1 (15/03/2004)PermalinkIntegrating imaging spectroscopy and neural networks to map grass quality in the Kruger National Park, South Africa / Onisimo Mutanga in Remote sensing of environment, vol 90 n° 1 (15/03/2004)PermalinkThe spatial distribution of indigenous forest and its composition in the Wellington region, New Zealand, from ETM+ satellite imagery / J.R. Dymond in Remote sensing of environment, vol 90 n° 1 (15/03/2004)PermalinkSurveillance et cartographie des plans d'eau et des zones humides et inondables en régions arides avec l'instrument Végétation embarqué sur SPOT-4 / Valéry Gond in International Journal of Remote Sensing IJRS, vol 25 n° 5 (March 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)PermalinkA basis for estimating digital camera parameters / D. Light in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 3 (March 2004)PermalinkEffets radiométriques en milieu urbain à grande échelle et correction des ombres / Gilles Martinoty in Géomatique expert, n° 32 (01/03/2004)PermalinkQuelques réflexions sur la réfraction d'un rayon lumineux dans l'air / R. Vincent in XYZ, n° 98 (mars - mai 2004)PermalinkReducing the dimensionality of plant spectral databases / I.E. Bell in IEEE Transactions on geoscience and remote sensing, vol 42 n° 3 (March 2004)PermalinkThe effect of scene elevation on the coherence of wide-angle crossing-node SAR pairs / T.M. Payne in IEEE Transactions on geoscience and remote sensing, vol 42 n° 3 (March 2004)PermalinkEstimation of land surface temperature-vegetation abundance relationship for urban heat island studies / Q. Wenger in Remote sensing of environment, vol 89 n° 4 (29/02/2004)PermalinkImpact of imagery temporal on land-cover change detection monitoring / R.S. Lunetta in Remote sensing of environment, vol 89 n° 4 (29/02/2004)PermalinkEffect of grain size on remotely sensed spectral reflectance of sandy desert surfaces / G.S. Okin in Remote sensing of environment, vol 89 n° 3 (15/02/2004)PermalinkEstimating fractional snow cover from MODIS using the normalized difference snow index / V.V. Salomonson in Remote sensing of environment, vol 89 n° 3 (15/02/2004)PermalinkPredicting in situ pasture quality in the Kruger National Park, South Africa, using continuum-removed absorption features / Onisimo Mutanga in Remote sensing of environment, vol 89 n° 3 (15/02/2004)PermalinkMapping the aerodynamic roughness length of desert surfaces from the POLDER/ADEOS bi-directional reflectance product / Béatrice Marticorena in International Journal of Remote Sensing IJRS, vol 25 n° 3 (February 2004)Permalink