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Training a neural network with a canopy reflectance model to estimate crop leaf area index / F. Mark Danson in International Journal of Remote Sensing IJRS, vol 24 n° 23 (December 2003)
[article]
Titre : Training a neural network with a canopy reflectance model to estimate crop leaf area index Type de document : Article/Communication Auteurs : F. Mark Danson, Auteur ; C.S. Rowland, Auteur Année de publication : 2003 Article en page(s) : pp 4891 - 4905 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] betterave sucrière
[Termes IGN] classification par réseau neuronal
[Termes IGN] indice de végétation
[Termes IGN] Leaf Area Index
[Termes IGN] neurone artificiel
[Termes IGN] réflectance végétaleRésumé : (Auteur) This paper outlines the strategies available for estimating the biophysical properties of crop canopies from remotely sensed data. Spectral reflectance and biophysical data were obtained over 132 plots of sugar beet (Beta vulgaris L.) and in the first part of the paper the strength of the relationships between vegetation indices (VI) and leaf area index (LAI) are examined. In the second part, an approach is tested in which a canopy reflectance model is used to generate simulated spectra for a wide range of biophysical conditions and these data are used to train an artificial neural network (ANN). The advantage of the second approach is that a priori knowledge of the measurement conditions including soil reflectance, canopy architecture and solar position can be included explicitly in the modelling. The results show that the estimation of sugar beet LAI using a trained neural network is more reliable than the use of VI and has the potential to replace the use of VI for operational applications. The use of a priori data on the variation in soil spectral reflectance gave rise to a small increase in LAI estimation accuracy. Numéro de notice : A2003-315 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000070319 En ligne : https://doi.org/10.1080/0143116031000070319 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22611
in International Journal of Remote Sensing IJRS > vol 24 n° 23 (December 2003) . - pp 4891 - 4905[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-03231 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Usefulness of spectral reflectance indices as durum wheat yield predictors under contrasting Mediterranean conditions / C. Royo in International Journal of Remote Sensing IJRS, vol 24 n° 22 (November 2003)
[article]
Titre : Usefulness of spectral reflectance indices as durum wheat yield predictors under contrasting Mediterranean conditions Type de document : Article/Communication Auteurs : C. Royo, Auteur ; N. Aparicio, Auteur ; D. Villegas, Auteur ; J. Casadesus, Auteur ; P. Monneveux, Auteur ; J.L. Araus, Auteur Année de publication : 2003 Article en page(s) : pp 4403 - 4419 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] blé (céréale)
[Termes IGN] couvert végétal
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] réflectance spectrale
[Termes IGN] réflectance végétale
[Termes IGN] rendement agricoleRésumé : (Auteur) Early prediction of crop yield can be an important tool for identifying promising genotypes in breeding programmes. To assess whether measurements of canopy reflectance at given stages of development could be used for yield forecasting and to identify the most appropriate indices, locations and growth stages for durum wheat yield assessment, nine field experiments, each including 20 or 25 durum wheat (Triticum turgidum L. var durum) genotypes, were carried out under a wide range of Mediterranean conditions. Canopy reflectance was recorded with a portable field spectroradiometer at several times from booting to physiological maturity. and nine indices were further derived. Grain yield15 was measured at harvesting. The results indicated that milkgrain stage was the most appropriate developmental stage for yield assessment. However, some indices were also sensitive to yield variations when determined at anthesis or even heading or booting. The capacity of spectral reflectance indices to forecast grain yield increased on locations that allowed genotypes to express their yield potentiality. Reflectance at 550 nm (R550), water index (WI), photochemical reflectance index (PRI). structural independent pigment index (SIPI), normalized difference vegetation index (NDVI) and simple ratio (SR) explained jointly a 95.7% of yield varlability when all the experiments were analysed together, 92% being explained by R550. When regression analyses were carried out separately for each experiment, spectral reflectance indices explained from 17.3% to 65.2% of total variation in yield. and the indices that best explained differences in yield were experimentdependent. Our data suggest that reflectance at 680 nm (R680), WI and SR may be suitable estimators of durum wheat grain yield under Mediterranean conditions, when determined at milkgrain stage. Numéro de notice : A2003-310 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000150059 En ligne : https://doi.org/10.1080/0143116031000150059 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22606
in International Journal of Remote Sensing IJRS > vol 24 n° 22 (November 2003) . - pp 4403 - 4419[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-03221 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Improvements in land use mapping for irrigated agriculture from satellite sensor data using a multi-stage maximum likelihood classification / I.A. El-Magd in International Journal of Remote Sensing IJRS, vol 24 n° 21 (November 2003)
[article]
Titre : Improvements in land use mapping for irrigated agriculture from satellite sensor data using a multi-stage maximum likelihood classification Type de document : Article/Communication Auteurs : I.A. El-Magd, Auteur ; T.W. Tanton, Auteur Année de publication : 2003 Article en page(s) : pp 4197 - 4206 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] carte agricole
[Termes IGN] carte d'occupation du sol
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] cultures
[Termes IGN] cultures irriguées
[Termes IGN] image Landsat-ETM+
[Termes IGN] rizière
[Termes IGN] utilisation du solRésumé : (Auteur) The accuracy of conventional land use classification of irrigated agriculture from optical satellite images using maximum likelihood supervised classification was compared with a classification based on multistage maxinium likelihood supervised classification. In the multistage maximum likelihood classification series of sub-classifications were carried out which included masking and/or omitting certain crops from the classifications. These series of classifications improved the identification of individual crops/land use types. The output from the optimum sub-classifications were stacked to give an overall crop types/land use map. When the multistage classification was tested against a single stage classification on a large irrigation scheme in Central Asia the final accuracy of crop/land use classification increased from 85% to 94%. Field verification confirmed the accuracy at 93.5%. These results were achieved with a single Landsat 7 Enhanced Thematic Mapper (ETM+) sensor dataset as of 2 August 1999 over an area of 38.5 km. Numéro de notice : A2003-305 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000139791 En ligne : https://doi.org/10.1080/0143116031000139791 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22601
in International Journal of Remote Sensing IJRS > vol 24 n° 21 (November 2003) . - pp 4197 - 4206[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-03211 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Towards an operational system for regional-scale rice yield estimation using a time-series of Radarsat ScanSAR images / Y. Li in International Journal of Remote Sensing IJRS, vol 24 n° 21 (November 2003)
[article]
Titre : Towards an operational system for regional-scale rice yield estimation using a time-series of Radarsat ScanSAR images Type de document : Article/Communication Auteurs : Y. Li, Auteur ; Q. Liao, Auteur ; X. Li, Auteur ; et al., Auteur Année de publication : 2003 Article en page(s) : pp 4207 - 4220 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Chine
[Termes IGN] cultures
[Termes IGN] image Radarsat
[Termes IGN] Oryza (genre)
[Termes IGN] production agricole
[Termes IGN] rendement agricole
[Termes IGN] surveillance agricoleRésumé : (Auteur) This paper demonstrates that Radarsat ScanSAR data can be an important data source of' radar remote sensing for monitoring crop systems and estimation of rice yield in large areas in tropical and sub-tropical regions. Experiments were carried out to show the effectiveness of Radarsat ScanSAR data for rice yield estimation in the whole province of Guangdong, South China. A methodology was developed to deal with a series of issues in extracting rice information from the ScanSAR data, such as topographic influences, levels of agro-management, irregular distribution of paddy fields and different rice cropping systems. A model was provided for rice yield estimation based on the relationship between the backscatter coefficient of multi-temporal SAR data and the biomass of rice. The study indicates that the whole procedure can become a low-cost and convenient operational system for large-scale rice yield estimation which is difficult for conventional methods. Numéro de notice : A2003-306 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000095970 En ligne : https://doi.org/10.1080/0143116031000095970 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22602
in International Journal of Remote Sensing IJRS > vol 24 n° 21 (November 2003) . - pp 4207 - 4220[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-03211 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Vegetation canopy anisotropy at 1.4 GHz / B.K. Hornbuckle in IEEE Transactions on geoscience and remote sensing, vol 41 n° 10 (October 2003)
[article]
Titre : Vegetation canopy anisotropy at 1.4 GHz Type de document : Article/Communication Auteurs : B.K. Hornbuckle, Auteur ; A.W. England, Auteur ; R.D. DE Roo, Auteur ; M.A. Fischman, Auteur ; D.L. Boprie, Auteur Année de publication : 2003 Article en page(s) : pp 2211 - 2223 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] angle d'incidence
[Termes IGN] anisotropie
[Termes IGN] couvert végétal
[Termes IGN] diffusion du rayonnement
[Termes IGN] humidité du sol
[Termes IGN] maïs (céréale)
[Termes IGN] modèle de transfert radiatif
[Termes IGN] télédétection en hyperfréquenceRésumé : (Auteur) We investigate anisotropy in 1.4 GHz brightness induced by a field corn vegetation canopy. We find that both polarizations of brightness are isotropic in azimuth during most of the growing season. When the canopy is senescent, the brightness is a strong function of row direction. On the other hand, the 1.4 GHz brightness is anisotropic in elevation : an isotropic zero-order radiative transfer model could not reproduce the observed change in brightness with incidence angle. Significant scatter darkening was found. The consequence of unanticipated scatter darkening would he a wet bias in soil moisture retrievals through a combination of underestimation of soil brightness (at H-pol) and underestimation of vegetation biomass (at V-pol). A new zero-order parameterization was formulated by allowing the volume scattering coefficient to be a function of incidence angle and polarization. The small magnitude of the scattering coefficients allows the zero-order to retain its limited physical significance. Numéro de notice : A2003-350 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/IGARSS.2003.1293767 En ligne : https://doi.org/10.1109/IGARSS.2003.1293767 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26430
in IEEE Transactions on geoscience and remote sensing > vol 41 n° 10 (October 2003) . - pp 2211 - 2223[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-03101 RAB Revue Centre de documentation En réserve L003 Disponible Crop yield assessment from remote sensing / P.C. Doraiswamy in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 6 (June 2003)PermalinkRemote sensing for crop management / P.J. Pinter in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 6 (June 2003)PermalinkComparison of Earth observing-1 ALI and Landsat ETM+ for crop identification and yield prediction in Mexico / D.B. Lobell in IEEE Transactions on geoscience and remote sensing, vol 41 n° 6 (June 2003)PermalinkLes SIG au secours de l'ONIC / Anonyme in Géomatique expert, n° 23 (01/02/2003)PermalinkEvaluation de la sensibilité à l'érosion des zones viticoles : influence des pratiques culturales (exemple du Fronsadais) / V. Herbreteau (2003)PermalinkMaking the trade-off between decision quality and information cost / S. De Bruin in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 1 (January 2003)PermalinkSchätzung von Vegetationsparametern aus multispektralen Fernerkundungsdaten / F. Kurz (2003)PermalinkSegmentation temporelle et spatiale de données agricoles / J.F. Mari in Revue internationale de géomatique, vol 12 n° 4 (décembre 2002 – février 2003)PermalinkComparative evaluation of Indian remote sensing multi-spectral sensors data for crop classification / R.P. Singh in Geocarto international, vol 17 n° 2 (June - August 2002)PermalinkEvaluation of narrowband and broadband vegetation indices for determining optimal hyperspectral wavebands for agricultural crop characterization / Prasad S. Thenkabail in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 6 (June 2002)Permalink