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Sensitivity of spectral reflectance values to different burn and vegetation ratios: A multi-scale approach applied in a fire affected area / Magdalini Pleniou in ISPRS Journal of photogrammetry and remote sensing, vol 79 (May 2013)
[article]
Titre : Sensitivity of spectral reflectance values to different burn and vegetation ratios: A multi-scale approach applied in a fire affected area Type de document : Article/Communication Auteurs : Magdalini Pleniou, Auteur ; Nikos Koustias, Auteur Année de publication : 2013 Article en page(s) : pp 199 - 210 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] affinage d'image
[Termes IGN] analyse comparative
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] Grèce
[Termes IGN] image Ikonos
[Termes IGN] image Landsat-SWIR
[Termes IGN] image Terra-ASTER
[Termes IGN] incendie de forêt
[Termes IGN] rayonnement proche infrarouge
[Termes IGN] régression multiple
[Termes IGN] sol nuRésumé : (Auteur) The aim of our study was to explore the spectral properties of fire-scorched (burned) and non fire-scorched (vegetation) areas, as well as areas with different burn/vegetation ratios, using a multisource multiresolution satellite data set. A case study was undertaken following a very destructive wildfire that occurred in Parnitha, Greece, July 2007, for which we acquired satellite images from LANDSAT, ASTER, and IKONOS. Additionally, we created spatially degraded satellite data over a range of coarser resolutions using resampling techniques. The panchromatic (1 m) and multispectral component (4 m) of IKONOS were merged using the Gram-Schmidt spectral sharpening method. This very high-resolution imagery served as the basis to estimate the cover percentage of burned areas, bare land and vegetation at pixel level, by applying the maximum likelihood classification algorithm. Finally, multiple linear regression models were fit to estimate each land-cover fraction as a function of surface reflectance values of the original and the spatially degraded satellite images. The main findings of our research were: (a) the Near Infrared (NIR) and Short-wave Infrared (SWIR) are the most important channels to estimate the percentage of burned area, whereas the NIR and red channels are the most important to estimate the percentage of vegetation in fire-affected areas; (b) when the bi-spectral space consists only of NIR and SWIR, then the NIR ground reflectance value plays a more significant role in estimating the percent of burned areas, and the SWIR appears to be more important in estimating the percent of vegetation; and (c) semi-burned areas comprising 45–55% burned area and 45–55% vegetation are spectrally closer to burned areas in the NIR channel, whereas those areas are spectrally closer to vegetation in the SWIR channel. These findings, at least partially, are attributed to the fact that: (i) completely burned pixels present low variance in the NIR and high variance in the SWIR, whereas the opposite is observed in completely vegetated areas where higher variance is observed in the NIR and lower variance in the SWIR, and (ii) bare land modifies the spectral signal of burned areas more than the spectral signal of vegetated areas in the NIR, while the opposite is observed in SWIR region of the spectrum where the bare land modifies the spectral signal of vegetation more than the burned areas because the bare land and the vegetation are spectrally more similar in the NIR, and the bare land and burned areas are spectrally more similar in the SWIR. Numéro de notice : A2013-237 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.02.016 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.02.016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32375
in ISPRS Journal of photogrammetry and remote sensing > vol 79 (May 2013) . - pp 199 - 210[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013051 RAB Revue Centre de documentation En réserve L003 Disponible Use of shadows for detection of earthquake-induced collapsed buildings in high-resolution satellite imagery / Xiaohua Tong in ISPRS Journal of photogrammetry and remote sensing, vol 79 (May 2013)
[article]
Titre : Use of shadows for detection of earthquake-induced collapsed buildings in high-resolution satellite imagery Type de document : Article/Communication Auteurs : Xiaohua Tong, Auteur ; Xiaofei Lin, Auteur ; Tiantian Feng, Auteur ; Huan Xie, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 53 - 67 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] bâtiment
[Termes IGN] cartographie des risques
[Termes IGN] détection d'ombre
[Termes IGN] dommage matériel
[Termes IGN] image à haute résolution
[Termes IGN] modèle 3D de l'espace urbain
[Termes IGN] ombre
[Termes IGN] risque naturel
[Termes IGN] séisme
[Termes IGN] Setchouan (Chine)
[Termes IGN] seuillage d'imageRésumé : (Auteur) In this paper, we present a hybrid shadow-analysis approach that integrates the model- and property-based methods for detecting collapsed buildings after an earthquake using high-resolution satellite imagery. The framework of the proposed approach has four main steps. (1) The three-dimensional (3D) building model is established according to its footprint and height data stored in a geographical information system. (2) The theoretical shadow area of the building at the time that the post-seismic image was acquired is calculated. And the polygon of the ground shadow area of the building, which is called the theoretical ground shadow polygon, is extracted. (3) The theoretical ground shadow polygon is overlaid with the casting shadow area of the building, which is called the actual shadow area in the post-seismic satellite image, and the mean value of the digital number values of the post-seismic image pixels within the polygon of the theoretical shadow area is calculated. (4) The calculated mean value is compared with predefined thresholds, which are determined by the training pixels collected from the different types of shadows. On this basis, the shadows of totally collapsed, partially collapsed and uncollapsed buildings can be distinguished. A comprehensive experiment for Dujiangyan city, one of the urban areas most severely damaged in the May 2008 Wenchuan Earthquake, was conducted, and the experimental results showed the superiority of the proposed approach to the other existing ones. Numéro de notice : A2013-233 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.01.012 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.01.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32371
in ISPRS Journal of photogrammetry and remote sensing > vol 79 (May 2013) . - pp 53 - 67[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013051 RAB Revue Centre de documentation En réserve L003 Disponible Assessing the impact of hydrocarbon leakages on vegetation using reflectance spectroscopy / I.D. Sanches in ISPRS Journal of photogrammetry and remote sensing, vol 78 (April 2013)
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Titre : Assessing the impact of hydrocarbon leakages on vegetation using reflectance spectroscopy Type de document : Article/Communication Auteurs : I.D. Sanches, Auteur ; C.R. Souza Filho, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 85 - 101 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse en composantes principales
[Termes IGN] canalisation
[Termes IGN] canopée
[Termes IGN] détection de changement
[Termes IGN] feuille (végétation)
[Termes IGN] forêt tropicale
[Termes IGN] hydrocarbure
[Termes IGN] réflectance végétaleRésumé : (Auteur) This paper assesses the capability of hyperspectral remote sensing to detect hydrocarbon leakages in pipelines using vegetation status as an indicator of contamination. A field experiment in real scale and in tropical weather was conducted in which Brachiaria brizantha H.S. pasture plants were grown over soils contaminated with small volumes of liquid hydrocarbons (HCs). The contaminations involved volumes of hydrocarbons that ranged between 2 L and 12.7 L of gasoline and diesel per m3 of soil, which were applied to the crop parcels over the course of 30 days. The leaf and canopy reflectance spectra of contaminated and control plants were acquired within 350–2500 nm wavelengths. The leaf and canopy reflectance spectra were mathematically transformed by means of first derivative (FD) and continuum removal (CR) techniques. Using principal component analysis (PCA), the spectral measurements could be grouped into either two or three contamination groups. Wavelengths in the red edge were found to contain the largest spectral differences between plants at distinct, evolving contamination stages. Wavelengths centred on water absorption bands were also important to differentiating contaminated from healthy plants. The red edge position of contaminated plants, calculated on the basis of FD spectra, shifted substantially to shorter wavelengths with increasing contamination, whereas non-contaminated plants displayed a red shift (in leaf spectra) or small blue shift (in canopy spectra). At leaf scale, contaminated plants were differentiated from healthy plants between 550–750 nm, 1380–1550 nm, 1850–2000 nm and 2006–2196 nm. At canopy scale, differences were substantial between 470–518 nm, 550–750 nm, 910–1081 nm, 1116–1284 nm, 1736–1786 nm, 2006–2196 nm and 2222–2378 nm. The results of this study suggests that remote sensing of B. brizantha H.S. at both leaf and canopy scales can be used as an indicator of gasoline and diesel contaminations for the detection of small leakages in pipelines. Numéro de notice : A2013-181 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.01.007 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.01.007 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32319
in ISPRS Journal of photogrammetry and remote sensing > vol 78 (April 2013) . - pp 85 - 101[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013041 RAB Revue Centre de documentation En réserve L003 Disponible Le bassin versant du Mayo-Tsagana (Nord Cameroun) : un bassin versant expérimental pour une compréhension des relations homme/milieu / Louise Leroux in Revue Française de Photogrammétrie et de Télédétection, n° 202 (Avril 2013)
[article]
Titre : Le bassin versant du Mayo-Tsagana (Nord Cameroun) : un bassin versant expérimental pour une compréhension des relations homme/milieu Type de document : Article/Communication Auteurs : Louise Leroux, Auteur ; Johan Oszwald, Auteur ; Benjamin Ngounou Ngatcha, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 42 - 54 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] bassin hydrographique
[Termes IGN] Cameroun
[Termes IGN] géomorphologie locale
[Termes IGN] image Landsat-ETM+
[Termes IGN] image Landsat-TM
[Termes IGN] image Terra-ASTER
[Termes IGN] interaction homme-milieu
[Termes IGN] modèle numérique de terrainRésumé : (Auteur) Depuis les trente dernières années, de nombreuses études scientifiques s'intéressent aux dynamiques hydrologiques relevées dans le bassin versant du lac Tchad. En effet, ce bassin versant a été, et est encore, une zone emblématique des impacts du changement climatique sur la ressource en eau en région sub-saharienne. la gestion de cette ressource est d'autant plus complexe que ce bassin versant se partage entre le Tchad, le Niger, le Nigeria et le Cameroun. Ce dernier, bien que important pour le fonctionnement hydrique du lac Tchad, est encore trop peu étudié par la communauté scientifique. Nous nous proposons donc de travailler sur le bassin versant du Mayo-Tsanaga, situé au Nord Cameroun et connecté au fleuve Logone, affluent du fleuve Chari et principal contributeur au bilan hydrique du lac Tchad. Quelques chercheurs de l'ORSTOM (Office de la Recherche Scientifique et Technique Outre-Mer) ont déjà travaillé sur ce bassin versant dans les années 1970, mais très peu de travaux ont été mis en place ces vingt-cinq dernières années sur celui-ci, de ce fait, il est primordial aujourd'hui, afin de pouvoir relancer une étude du bassin versant du Mayo-Tsanaga par instrumentation, de remettre à jour nos connaissances géomorphologiques, hydrographiques et d'occupation du sol. Pour ce faire, nous avons recours à des données récentes et plus précises (MNT Aster, images satellites Landsat TM et ETM+) afin de suivre les dynamiques Hommes / milieux ayant cours depuis les 25 dernières années. Ce travail montre une mutation et une organisation complexe des pratiques, en relation notamment avec la géomorphologie et la pédologie du bassin versant du Mayo-Tsanaga. Numéro de notice : A2013-315 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.52638/rfpt.2013.50 En ligne : https://doi.org/10.52638/rfpt.2013.50 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32453
in Revue Française de Photogrammétrie et de Télédétection > n° 202 (Avril 2013) . - pp 42 - 54[article]Quality assessment of cloud-top height estimates from satellite IR radiances using the CALIPSO Lidar / Sabatino, Di Michele in IEEE Transactions on geoscience and remote sensing, vol 51 n° 4 Tome 2 (April 2013)
[article]
Titre : Quality assessment of cloud-top height estimates from satellite IR radiances using the CALIPSO Lidar Type de document : Article/Communication Auteurs : Sabatino, Di Michele, Auteur ; Tony Mcnally, Auteur ; Peter Bauer, Auteur ; Iliana Genkova, Auteur Année de publication : 2013 Article en page(s) : pp 2454 - 2464 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Atmospheric Infrared Sounder
[Termes IGN] CALIPSO
[Termes IGN] détection des nuages
[Termes IGN] données lidar
[Termes IGN] estimation de précision
[Termes IGN] radianceRésumé : (Auteur) This paper summarizes the studies performed using data from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) to verify cloud variables in the context of the European Centre for Medium-Range Weather Forecasts assimilation system. In the first part of this paper, the cloud-top height (CTH) derived from the Atmospheric Infrared Sounder (AIRS) radiances has been compared with the same quantity from CALIPSO exploiting the spatial and temporal coincidence guaranteed by the A-Train constellation. In the second part, the CTH from CALIPSO has been used to verify the wind height assignment (HA) for the atmospheric motion vectors (AMVs) derived from Meteosat geostationary cloudy radiances. Two different estimates from AIRS have been considered: one derived from the cloud detection scheme and the other used within the assimilation of infrared (IR) cloudy radiances. The verification of cloud detection for hyperspectral IR sounders has revealed some difficulties with cirrus clouds. The verification of CTH for the assimilation of IR cloudy radiances has shown a reasonable agreement when the lidar signal is fully attenuated but a larger scatter in other conditions. The verification of AMV HA revealed an overall tendency to produce CTHs lower than CALIPSO for high clouds and the opposite for low clouds. Interestingly, a similar behavior was observed in the validation of CTHs for the assimilation of IR cloudy radiances. Numéro de notice : A2013-226 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2012.2210721 En ligne : https://doi.org/10.1109/TGRS.2012.2210721 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32364
in IEEE Transactions on geoscience and remote sensing > vol 51 n° 4 Tome 2 (April 2013) . - pp 2454 - 2464[article]Réservation
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