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Thermal re-emission effects on GPS satellites / J. Duha in Journal of geodesy, vol 80 n° 12 (December 2006)
[article]
Titre : Thermal re-emission effects on GPS satellites Type de document : Article/Communication Auteurs : J. Duha, Auteur ; G.B. Afonso, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 665 - 674 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] albedo
[Termes IGN] émission thermique
[Termes IGN] modèle mathématique
[Termes IGN] orbitographie
[Termes IGN] perturbation orbitale
[Termes IGN] photon
[Termes IGN] rayonnement solaire
[Termes IGN] satellite GPSRésumé : (Auteur) Highly precise satellite-derived coordinates depend on accurate orbit predictions, which cannot be achieved with purely empirical models. Global positioning system (GPS) satellites undergo several periodic perturbing forces that have to be modeled and understood. In this scenario, small non-gravitational forces can no longer be neglected when the purpose of the orbital analysis is to obtain accurate results (Vilhena de Moraes 1994). Together with solar radiation pressure, thermal re-emission effects due to solar heating and Earth albedo are the two most important non-gravitational effects. While solar radiation pressure is widely understood, our knowledge about thermal re-emission effects on GPS satellites is in its infancy. Few models have been proposed in recent years and despite the interest of the scientific community, there is a lack of detailed results concerning the magnitude and the behavior of such forces. The aim of this work is to provide a thermal re-emission force model for GPS satellites, simple enough to minimize the problem of modeling a satellite of complex shape with several components on its surface, but accurate enough to provide an estimate of the magnitude and the behavior of these forces, as well as to provide some input to the present knowledge about photon thrust on GPS satellites. Some results of this work point to the fact that thermal re-emission effects are good candidates to partially explain the Y-bias for GPS satellites. Copyright Springer Numéro de notice : A2006-538 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-006-0060-x En ligne : https://doi.org/10.1007/s00190-006-0060-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28261
in Journal of geodesy > vol 80 n° 12 (December 2006) . - pp 665 - 674[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-06111 RAB Revue Centre de documentation En réserve L003 Disponible 266-06112 RAB Revue Centre de documentation En réserve L003 Disponible Exploiting class hierarchies for knowledge transfer in hyperspectral data / S. Rajan in IEEE Transactions on geoscience and remote sensing, vol 44 n° 11 Tome 2 (November 2006)
[article]
Titre : Exploiting class hierarchies for knowledge transfer in hyperspectral data Type de document : Article/Communication Auteurs : S. Rajan, Auteur ; J. Ghosh, Auteur ; Melba M. Crawford, Auteur Année de publication : 2006 Article en page(s) : pp 3408 - 3417 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] classification ascendante hiérarchique
[Termes IGN] classification non dirigée
[Termes IGN] données multitemporelles
[Termes IGN] image hyperspectrale
[Termes IGN] signature spectraleRésumé : (Auteur) Obtaining ground truth for classification of remotely sensed data is time consuming and expensive, resulting in poorly represented signatures over large areas. In addition, the spectral signatures of a given class vary with location and/or time. Therefore, successful adaptation of a classifier designed from the available labeled data to classify new hyperspectral images acquired over other geographic locations or subsequent times is difficult, if minimal additional labeled data are available. In this paper, the binary hierarchical classifier is used to propose a knowledge transfer framework that leverages the information extracted from the existing labeled data to classify spatially separate and multitemporal test data. Experimental results show that in the absence of any labeled data in the new area, the approach is better than a direct application of the original classifier on the new data. Moreover, when small amounts of the labeled data are available from the new area, the framework offers further improvements through semisupervised learning mechanisms and compares favorably with previously proposed methods. Copyright IEEE Numéro de notice : A2006-528 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2006.878442 En ligne : https://doi.org/10.1109/TGRS.2006.878442 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28251
in IEEE Transactions on geoscience and remote sensing > vol 44 n° 11 Tome 2 (November 2006) . - pp 3408 - 3417[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-06111B RAB Revue Centre de documentation En réserve L003 Disponible Spectral normalisation and fusion of optical sensors for the retrieval of BRDF and albedo: application to vegetation, MODIS, and MERIS data sets / O. Samain in IEEE Transactions on geoscience and remote sensing, vol 44 n° 11 Tome 1 (November 2006)
[article]
Titre : Spectral normalisation and fusion of optical sensors for the retrieval of BRDF and albedo: application to vegetation, MODIS, and MERIS data sets Type de document : Article/Communication Auteurs : O. Samain, Auteur ; Bernhard Geiger, Auteur ; Jean-Louis Roujean, Auteur Année de publication : 2006 Article en page(s) : pp 3166 - 3179 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Afrique occidentale
[Termes IGN] albedo
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] fusion d'images
[Termes IGN] image à moyenne résolution
[Termes IGN] image Envisat-MERIS
[Termes IGN] image multicapteur
[Termes IGN] image optique
[Termes IGN] image SPOT-Végétation
[Termes IGN] image Terra-MODIS
[Termes IGN] série temporelle
[Termes IGN] signature spectraleRésumé : (Auteur) This paper aims at demonstrating the possibility of merging data from various medium-resolution spaceborne sensors to produce a consistent time series of surface bidirectional reflectance distribution function (BRDF) and albedo products. The spectral, directional, temporal, and spatial aspects of the multisensor fusion are presented. Emphasis is then given on the spectral normalization for the fusion of Medium Resolution Imaging Spectrometer Instrument (MERIS) data with Moderate Resolution Imaging Spectroradiometer (MODIS) and VEGETATION (VGT) data. Two methods are evaluated: a simple statistical method, which relies on a linear regression using all the available spectral bands, and a more innovative method called the spectral mode method, which is based on the restitution of the surface spectral signature by a combination of universal spectral functions. Analysis with Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) hyperspectral data and satellite products reveals that the spectral mode method is more efficient. This approach is used to merge top-of-canopy bidirectional reflectances from MERIS and VGT for the restitution of BRDF and albedo over a subset of West Africa. Compared to the products obtained with MERIS alone, the fusion with VGT demonstrates an improvement of the spatial coverage and a reduction of product uncertainty by about a third. Copyright IEEE Numéro de notice : A2006-509 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2006.879545 En ligne : https://doi.org/10.1109/TGRS.2006.879545 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28233
in IEEE Transactions on geoscience and remote sensing > vol 44 n° 11 Tome 1 (November 2006) . - pp 3166 - 3179[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-06111A RAB Revue Centre de documentation En réserve L003 Disponible Urban surface biophysical descriptors and land surface temperature variations / D. Weng in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 11 (November 2006)
[article]
Titre : Urban surface biophysical descriptors and land surface temperature variations Type de document : Article/Communication Auteurs : D. Weng, Auteur ; Dong Lu, Auteur ; B. Liang, Auteur Année de publication : 2006 Article en page(s) : pp 1275 - 1286 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] albedo
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] émission thermique
[Termes IGN] flore locale
[Termes IGN] image Landsat-ETM+
[Termes IGN] Indianapolis
[Termes IGN] milieu urbain
[Termes IGN] morphologie urbaine
[Termes IGN] occupation du sol
[Termes IGN] surface imperméable
[Termes IGN] température de surface
[Termes IGN] variable biophysique (végétation)
[Termes IGN] zone urbaineRésumé : (Auteur) In remote sensing studies of land surface temperatures (LST), thematic land-use and land-cover (LULC) data are frequently employed for simple correlation analyses between LULC types and their thermal signatures. Development of quantitative surface descriptors could improve our capabilities for modeling urban thermal landscapes and advance urban climate research. This study developed an analytical procedure based upon a spectral unmixing model for characterizing and quantifying the urban landscape in Indianapolis, Indiana. A Landsat Enhanced Thematic Mapper Plus image of the study area, acquired on 22 June 2002, was spectrally unmixed into four fraction endmembers, namely, green vegetation, soil, high and low albedo. Impervious surface was then computed from the high and low albedo images. A hybrid classification procedure was developed to classify the fraction images into seven land-use and land-cover classes. Next, pixel-based LST measurements were related to urban surface biophysical descriptors derived from spectral mixture analysis (SMA). Correlation analyses were conducted to investigate land-cover based relationships between LST and impervious surface and green vegetation fractions for an analysis of the causes of LST variations. Results indicate that fraction images derived from SMA were effective for quantifying the urban morphology and for providing reliable measurements of biophysical variables such as vegetation abundance, soil, and impervious surface. An examination of LST variations within census block groups and their relationships with the compositions of LULC types, biophysical descriptors, and other relevant spatial data shows that LST possessed a weaker relation with the LULC compositions than with other variables (including urban biophysical descriptors, remote sensing biophysical variables, GIS-based impervious surface variables, and population density). Further research should be directed to refine spectral mixture modeling. The use of multi-temporal remote sensing data for urban time-space modeling and comparison of urban morphology in different geographical settings are also feasible. Copyright ASPRS Numéro de notice : A2006-493 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.72.11.1275 En ligne : https://doi.org/10.14358/PERS.72.11.1275 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28217
in Photogrammetric Engineering & Remote Sensing, PERS > vol 72 n° 11 (November 2006) . - pp 1275 - 1286[article]Integration of MODIS data into a simple model for the spatial distributed simulation of soil water content and evapotranspiration / Y. Zhang in Remote sensing of environment, vol 104 n° 4 (30/10/2006)
[article]
Titre : Integration of MODIS data into a simple model for the spatial distributed simulation of soil water content and evapotranspiration Type de document : Article/Communication Auteurs : Y. Zhang, Auteur ; M. Wegehenkel, Auteur Année de publication : 2006 Article en page(s) : pp 393 - 408 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Allemagne
[Termes IGN] analyse diachronique
[Termes IGN] évapotranspiration
[Termes IGN] humidité du sol
[Termes IGN] image Terra-MODIS
[Termes IGN] Leaf Area Index
[Termes IGN] réflectance
[Termes IGN] simulationRésumé : (Auteur) A precise simulation of soil water content (SWC) and actual evapotranspiration (ETa) in a region or a catchment depends on the accuracy of the spatial data inputs. In this study, we developed a simple grid-based soil water balance model. In this model, remotely sensed vegetation data are used to estimate spatial distributions of daily SWC and ETa rates. The model was validated by comparing simulated SWC with the measured by gravimetric method and time domain reflectometry (TDR) at an experimental test site located in Northeastern Germany in the time period 1993–1998. The index of agreement IA and the root-mean-square error obtained from the comparison of the TDR measurements to the simulated values ranged from 0.45 to 0.80 and from 0.029 to 0.061 cm3/cm3, respectively. The comparison of simulated ETa rates to those measured by four large-scale lysimeters at another test site showed IA values above 0.87 and R2 values higher than 0.59. For the regional application of the model, a method was developed to integrate the Moderate Resolution Imaging Spectrometer (MODIS) vegetation data into the model. The MODIS data used in our study consist of 16-day normalized difference vegetation index and 8-day leaf area index products. Regarding the spatial application of the model, our approach was tested in a catchment located in Northeastern Germany in 2001–2003. A sufficient correlation between daily discharge rates measured at two observation gauges in the catchment and the corresponding simulated discharge rates and also good correlations between the simulated ETa rates and the MODIS-leaf area index values indicate that the model is an appropriate simulation tool at regional scale if the corresponding additional spatial databases regarding surface and soil properties are available. Copyright Elsevier Numéro de notice : A2006-496 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2006.05.011 En ligne : https://doi.org/10.1016/j.rse.2006.05.011 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28220
in Remote sensing of environment > vol 104 n° 4 (30/10/2006) . - pp 393 - 408[article]Evaluating temporal variability in the spectral reflectance response of annual ryegrass to changes in nitrogen applications and leaching fractions / M. Baghzouz in International Journal of Remote Sensing IJRS, vol 27 n°18 - 19 - 20 (October 2006)PermalinkEvaluation of hyperspectral data for geological mapping / Muneendra Kumar in Geoinformatics, vol 9 n° 6 (01/09/2006)PermalinkComparison of spectral indices obtained using multiple spectroradiometers / K.L. Castro-Esau in Remote sensing of environment, vol 103 n° 3 (15 August 2006)PermalinkMapping carbon and water vapor fluxes in a chaparral ecosystem using vegetation indices derived from AVIRIS / D.A. Fuentes in Remote sensing of environment, vol 103 n° 3 (15 August 2006)PermalinkOn the blending of the Landsat and MODIS surface reflectance: predicting daily Landsat surface reflectance / F. Gao in IEEE Transactions on geoscience and remote sensing, vol 44 n° 8 (August 2006)PermalinkThe effect of E-M wave's attenuation on sea surface reflectivity, emissivity and estimation of sea surface temperature / Q. Xu in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 5 (August 2006)PermalinkEvaluation of the potential of SAR ERS and ASAR Envisat sensors in multi-incidence and multi-polarisation modes for landscape study in French Guyana: examples of Kourou and Saint Laurent du Maroni / J.L. Kouame in Revue Française de Photogrammétrie et de Télédétection, n° 182 (Juin 2006)PermalinkHigh spatial resolution satellite imagery, DEM derivatives, and image segmentation for the detection of mass wasting processes / J. Barlow in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 6 (June 2006)PermalinkCoal fire mapping from satellite thermal IR data: a case example in Jharia Coalfield, Jharkhand, India / R.S. Chatterjee in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 2 (April 2006)PermalinkSea ice monitoring by L-band SAR: an assessment based on literature and comparisons of JERS-1 and ERS-1 imagery / W. Dierking in IEEE Transactions on geoscience and remote sensing, vol 44 n° 4 (April 2006)Permalink