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The emissivity of foam-covered water surface at L-band: theoretical modelling and experimental results from the frog 2003 field experiment / A. Camps in IEEE Transactions on geoscience and remote sensing, vol 43 n° 5 (May 2005)
[article]
Titre : The emissivity of foam-covered water surface at L-band: theoretical modelling and experimental results from the frog 2003 field experiment Type de document : Article/Communication Auteurs : A. Camps, Auteur ; M. Vall-Llossera, Auteur ; R. Villarino, Auteur Année de publication : 2005 Article en page(s) : pp 925 - 937 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] angle d'incidence
[Termes IGN] bande L
[Termes IGN] emissivité
[Termes IGN] houle
[Termes IGN] polarisation
[Termes IGN] salinité
[Termes IGN] spectre électromagnétique
[Termes IGN] surface de la mer
[Termes IGN] télédétection en hyperfréquenceRésumé : (Auteur) Sea surface salinity can he measured by microwave radiometry at L-band (1400-1427 MHz). This frequency is a compromise between sensitivity to the salinity, small atmospheric perturbation, and reasonable pixel resolution. The description of the ocean emission depends on two main factors: 1) the sea water permittivity, which is a function of salinity, temperature, and frequency, and 2) the sea surface state, which depends on the wind-induced wave spectrum, swell, and rain-induced roughness spectrum, and by the foam coverage and its emissivity. This study presents a simplified two-layer emission model for foam-covered water and the results of a controlled experiment to measure the foam emissivity as a function of salinity, foam thickness, incidence angle, and polarization. Experimental results are presented, and then compared to the two-layer foam emission model with the measured foam parameters used as input model parameters. At 37 psu salt water the foam-induced emissivity increase is ~0.007 per millimeter of foam thickness (extrapolated to nadir), increasing with increasing incidence angles at vertical polarization, and decreasing with increasing incidence angles at horizontal polarization. Numéro de notice : A2005-213 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2004.839651 En ligne : https://doi.org/10.1109/TGRS.2004.839651 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27350
in IEEE Transactions on geoscience and remote sensing > vol 43 n° 5 (May 2005) . - pp 925 - 937[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-05051 RAB Revue Centre de documentation En réserve L003 Disponible Estimating tropical pasture quality at canopy level using band depth analysis with continuum removal in the visible domain / Onisimo Mutanga in International Journal of Remote Sensing IJRS, vol 26 n° 6 (March 2005)
[article]
Titre : Estimating tropical pasture quality at canopy level using band depth analysis with continuum removal in the visible domain Type de document : Article/Communication Auteurs : Onisimo Mutanga, Auteur ; Andrew K. Skidmore, Auteur ; et al., Auteur Année de publication : 2005 Article en page(s) : pp 1093 - 1108 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] analyse spectrale
[Termes IGN] bande visible
[Termes IGN] contrôle qualité
[Termes IGN] faune
[Termes IGN] forêt tropicale
[Termes IGN] herbe
[Termes IGN] paturage
[Termes IGN] radiométrie
[Termes IGN] réflectance végétale
[Termes IGN] régression linéaire
[Termes IGN] zone intertropicaleRésumé : (Auteur) Pasture quality, expressed as a percentage of total digestible nutients (nitrogen, potassium, phosphorous, calcium and magnesium) is a major factor determining the grazing patterns of wildlife and livestock. Existing rangeland monitoring techniques seldom reflect the nutritive quality of the pastures and are consequently of limited value in explaining animal distribution. Techniques that can estimate pasture quality on a large scale are therefore critical in understanding and explaining wildlife and livestock distribution. We present the results of a greenhouse experiment designed to estimate the concentrations of nitrogen, potassium, phosphorous calcium, magnesium and non-detergent fibre (NDF), using the reflectance of a tropical grass (Cenchrus ciliaris) canopy. Canopy spectral measurements were taken under controlled laboratory conditins using a GER 3700 spectroradiometer. We tested the utility of using the band depth analysis methodology in the visible region (where water absorption is less effective) to estimate foliar chemistry in fresh canopies. Continuum removal was applied to the visible absorption feature centred at 670 nm, and band depth ratios (BDRs) were calculated. Stepwise linear regression was used to select wavelenghts from calculated BDRs that were highly correlated with foliar chemistry in randomly selected training dataset. The resulting regression models were used to predict foliar chemistry in a test dataset. Results indicate that stepwise regression models on band calculated from continuum-removed reflectance spectra could predict foliar nutrient concentration with high accuracy. The correlations were highest for magnesium and nitrogen (R2= 0.77 and 0.73 respectively, using the normalized band depth index (NDBI) between the measured and estimated biochemicals - a satisfactory result in estimating foliar chemistry in fresh standing pastures. With the advent of new sensors such as Hymap and MERIS these results lay the basis for developing algorithms to rapidly estimate and ultimately map pasture quality in tropical rangelands. Numéro de notice : A2005-145 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160512331326738 En ligne : https://doi.org/10.1080/01431160512331326738 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27283
in International Journal of Remote Sensing IJRS > vol 26 n° 6 (March 2005) . - pp 1093 - 1108[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-05061 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Analysis of the spectral variability of urban materials for classification : A case study over Toulouse (France) / Sophie Lacherade (2005)
Titre : Analysis of the spectral variability of urban materials for classification : A case study over Toulouse (France) Type de document : Article/Communication Auteurs : Sophie Lacherade, Auteur ; Christophe Miesch, Auteur ; F. LemaÎtre, Auteur ; Xavier Briottet , Auteur ; Hervé Le Men , Auteur ; Didier Boldo , Auteur ; Christophe Valorge, Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2005 Collection : International Archives of Photogrammetry and Remote Sensing, ISSN 0252-8231 num. 36-8/W27 Conférence : ISPRS 2005, WG VIII/1, Joint Symposia URBAN - URS 14/03/2005 16/03/2005 Tempe Arizona - Etats-Unis OA ISPRS Archives Importance : 3 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] bande visible
[Termes IGN] classification
[Termes IGN] image proche infrarouge
[Termes IGN] milieu urbain
[Termes IGN] réflectance spectrale
[Termes IGN] Toulouse
[Termes IGN] variabilitéRésumé : (auteur) The automatic classification of urban materials from airborne and spatial acquisitions remains difficult today because of two main reasons: the spatial resolution of the images and the need for pre-processing algorithms to extract ground surface intrinsic properties. This work examines the feasibility of using 8 spectral information distributed in the visible and the near-infrared spectral regions (0.4 - 1 μm), acquired at a 20 cm spatial resolution, for recognizing the urban materials. The motivation for this study is the development of very high spatial resolution sensors which has introduced a promising capability for the study of urban areas. In this study , an experiment campaign took place in Toulouse. The airborne measurements were carried out using 8 cameras associated with 8 narrow filters (30 nm). Ground spectral measurements of Toulouse's urban materials were performed within the configuration of the airborne acquisitions. These measurements allow us to determine and quantify three types of reflectance spatial variability. The results show that urban materials have low reflectances with no significant spectral features and are then difficult to discriminate. To determine which material classes could be discriminate over the 8 spectral bands of the airborne acquisitions, a statistical analysis was performed on the ground measurements. This analysis highlights that 5 material classes could be discriminated from good quality measurements. Numéro de notice : C2005-036 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE/INFORMATIQUE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : https://www.isprs.org/proceedings/XXXVI/8-W27/lacherade.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100079 Spatial resolution and processing tradeoffs for HYDROS: application of reconstruction and resolution enhancement techniques / David G. Long in IEEE Transactions on geoscience and remote sensing, vol 43 n° 1 (January 2005)
[article]
Titre : Spatial resolution and processing tradeoffs for HYDROS: application of reconstruction and resolution enhancement techniques Type de document : Article/Communication Auteurs : David G. Long, Auteur Année de publication : 2005 Article en page(s) : pp 3 - 12 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] accentuation d'image
[Termes IGN] bande L
[Termes IGN] capteur (télédétection)
[Termes IGN] humidité du sol
[Termes IGN] HYDROS
[Termes IGN] Hydrospheric State
[Termes IGN] image à basse résolution
[Termes IGN] mission spatiale
[Termes IGN] radiomètre à hyperfréquence
[Termes IGN] reconstruction d'imageRésumé : (Auteur) Recent developments in reconstruction and resolution enhancement for microwave instruments suggest a possible tradeoff between computation, resolution, and downlink data rate based on postcollection reconstruction/resolution enhancement processing. The Hydrospheric State mission is designed to measure global soil moisture and freeze/thaw state in support of weather and climate prediction, water, energy, and carbon cycle studies, and natural hazards monitoring. It will use an active and passive L-band microwave system that optimizes measurement accuracy, spatial resolution, and coverage. The active channels use synthetic aperture radar-type processing to achieve fine spatial resolution, requiring a relatively high downlink data rate and ground processor complexity. To support real-time applications and processing, an optional postcollection reconstruction and resolution enhancement method is investigated. With this option, much lower rate real-aperture radar data are used along with ground-based postprocessing algorithms to enhance the resolution of the observations to achieve the desired 10-km resolution. Several approaches are investigated in this paper. It is determined that a reconstruction/resolution enhancement technique combining both forward- and aft-looking measurements enables estimation of 10-km resolution or better backscatter values at acceptable accuracy. Key tradeoffs to achieve this goal are considered. Numéro de notice : A2005-057 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2004.838385 En ligne : https://doi.org/10.1109/TGRS.2004.838385 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27195
in IEEE Transactions on geoscience and remote sensing > vol 43 n° 1 (January 2005) . - pp 3 - 12[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-05011 RAB Revue Centre de documentation En réserve L003 Disponible Automated road extraction from high resolution multispectral imagery / P. Doucette in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 12 (December 2004)
[article]
Titre : Automated road extraction from high resolution multispectral imagery Type de document : Article/Communication Auteurs : P. Doucette, Auteur ; Peggy Agouris, Auteur ; A. Stefanidis, Auteur Année de publication : 2004 Article en page(s) : pp 1405 - 1416 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] axe médian
[Termes IGN] bande infrarouge
[Termes IGN] banlieue
[Termes IGN] classification dirigée
[Termes IGN] extraction automatique
[Termes IGN] extraction du réseau routier
[Termes IGN] image à haute résolution
[Termes IGN] image en couleur
[Termes IGN] image multibande
[Termes IGN] logique floue
[Termes IGN] milieu urbain
[Termes IGN] parallélisme
[Termes IGN] topologieRésumé : (Auteur) This work presents a novel methodology for fully automated road centerline extraction that exploits spectral content from high resolution multispectral images. Preliminary detection of candidate road centerline components is performed with Anti-parallel-edge Centerline Extraction (ACE). This is followed by constructing a road vector topology with a fuzzy grouping model that links nodes from a self-organized mapping of the ACE components. Following topology construction, a Self-Supervised Road Classification (SSRC) feedback loop is implemented to automate the process of training sample selection and refinement for a road class, as well as deriving practical spectral definitions for non-road classes. SSRC demonstrates a potential to provide dramatic improvement in road extraction results by exploiting spectral content. Road centerline extraction results are presented for three 1 m color infrared suburban scenes which show significant improvement following SSRC. Numéro de notice : A2004-502 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.70.12.1405 En ligne : https://doi.org/10.14358/PERS.70.12.1405 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27019
in Photogrammetric Engineering & Remote Sensing, PERS > vol 70 n° 12 (December 2004) . - pp 1405 - 1416[article]Road extraction using SVM and image segmentation / M. Song in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 12 (December 2004)PermalinkAssessing the feasibility of a global model for multi-temporal burned area mapping using Spot-Vegetation data / J.M. Silva in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)PermalinkDiscrimination potential of X-band polarimetric SAR data / Nicolas Baghdadi in International Journal of Remote Sensing IJRS, vol 25 n° 22 (November 2004)PermalinkThe use of AVHRR data to determine the concentration of visible and invisible tropospheric pollutants originating from a 1997 forest fire in Southeast Asia / M. Hashim in International Journal of Remote Sensing IJRS, vol 25 n° 21 (November 2004)PermalinkThe contribution of the sources separation method in the decomposition of mixed pixels / Mohamed Saber Naceur in IEEE Transactions on geoscience and remote sensing, vol 42 n° 11 (November 2004)PermalinkThe development of superspectral approaches for the improvement of land cover classification / M. Gianinetto in IEEE Transactions on geoscience and remote sensing, vol 42 n° 11 (November 2004)PermalinkRetrieval of soil moisture from passive and active L/S band sensor (PALS) observations during the soil moisture experiment in 2002 (SMEX) / U. Narayan in Remote sensing of environment, vol 92 n° 4 (30 September 2004)PermalinkAn assessment of the effectiveness of atmospheric correction algorithms through the remote sensing of some reservoirs / D.G. Hadjimitsis in International Journal of Remote Sensing IJRS, vol 25 n° 18 (September 2004)PermalinkContinental scale hotspot observations of Australia at sub-degree angular resolution from POLDER / F. Grant in International Journal of Remote Sensing IJRS, vol 25 n° 18 (September 2004)PermalinkExtrapolation of the aerosol reflectance from the near-infrared to the visible : the single-scattering epsilon vs multiple-scattering epsilon method / M. Wang in International Journal of Remote Sensing IJRS, vol 25 n° 18 (September 2004)Permalink