Descripteur
Documents disponibles dans cette catégorie (881)
![](./images/expand_all.gif)
![](./images/collapse_all.gif)
Etendre la recherche sur niveau(x) vers le bas
Wind resource assessment from C-band SAR / M.B. Christiansen in Remote sensing of environment, vol 105 n° 1 (15/11/2006)
![]()
[article]
Titre : Wind resource assessment from C-band SAR Type de document : Article/Communication Auteurs : M.B. Christiansen, Auteur ; W Koch, Auteur Année de publication : 2006 Article en page(s) : pp 68 - 81 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] analyse comparative
[Termes IGN] bande C
[Termes IGN] direction
[Termes IGN] écart type
[Termes IGN] erreur systématique
[Termes IGN] gradient
[Termes IGN] image Envisat-ASAR
[Termes IGN] image ERS-SAR
[Termes IGN] Nord, mer du
[Termes IGN] vent
[Termes IGN] vitesseRésumé : (Auteur) Using accurate inputs of wind speed is crucial in wind resource assessment, as predicted power is proportional to the wind speed cubed. First, wind speeds retrieved from a series of 91 ERS-2 SAR and Envisat ASAR images, at moderate wind speeds (2–15 m s- 1), were validated against in situ measurements from an offshore mast in the North Sea. The wind direction input, necessary for SAR wind speed retrievals, was obtained from the meteorological mast and from a local gradient analysis of wind streaks in the SAR images. A wind speed standard deviation of not, vert, similar 1.1 m s- 1 was found when in situ wind directions were used. The use of local gradient wind directions yielded a standard deviation of not, vert, similar 1.3 m s- 1. Wind speeds retrieved from three geophysical model functions (CMOD-IFR2, CMOD4, and CMOD5) were compared. The best approximation to the in situ measurements of wind speed was found for CMOD-IFR2, despite a bias on the order of - 0.3 m s- 1. CMOD4 retrievals also underestimated the wind speed, whereas the bias on CMOD5 retrievals was negligible. Then, wind resource assessments were made from the SAR-based wind observations to show how errors in wind speed from the different SAR wind retrievals were reflected in the wind statistics. The mean wind speed, obtained for all of the 91 SAR scenes, was linked closely to the bias of SAR wind retrievals. Agreement to 1 15% of the in situ measurements was found for all the wind retrieval methods tested. The accuracy of power density estimates for the entire data set was evaluated by the standard deviation of SAR wind retrievals relative to the in situ measurements. SAR wind fields retrieved with CMOD-IFR2, using in situ wind direction inputs, exactly yielded the power density predicted from in situ measurements alone. The SAR-based wind resource assessment also corresponded well to predictions from longer time series of in situ measurements. This indicates that a reliable wind resource assessment may be achieved from a series of randomly selected SAR images. The findings presented here could be useful in future wind resource assessment based on SAR images. Copyright Elsevier Numéro de notice : A2006-503 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2006.06.005 En ligne : https://doi.org/10.1016/j.rse.2006.06.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28227
in Remote sensing of environment > vol 105 n° 1 (15/11/2006) . - pp 68 - 81[article]Assessment of EOS aqua AMSR-E artic sea ice concentrations using Landsat-7 and airborne microwave imagery / D.J. Cavalieri in IEEE Transactions on geoscience and remote sensing, vol 44 n° 11 Tome 1 (November 2006)
![]()
[article]
Titre : Assessment of EOS aqua AMSR-E artic sea ice concentrations using Landsat-7 and airborne microwave imagery Type de document : Article/Communication Auteurs : D.J. Cavalieri, Auteur ; T. Markus, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 3057 - 3069 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image mixte
[Termes IGN] analyse comparative
[Termes IGN] Arctique, océan
[Termes IGN] erreur moyenne quadratique
[Termes IGN] glace de mer
[Termes IGN] image aérienne
[Termes IGN] image Aqua-AMSR
[Termes IGN] image Landsat-ETM+
[Termes IGN] image radar
[Termes IGN] photographie aérienne
[Termes IGN] photographie numériqueRésumé : (Auteur) An assessment of Advanced Microwave Scanning Radiometer Earth Observing System (AMSR-E) sea ice concentrations under winter conditions using ice concentrations derived from Landsat-7 Enhanced Thematic Mapper Plus (ETM+) imagery obtained during the March 2003 Arctic sea ice validation field campaign is presented. The National Oceanic and Atmospheric Administration Environmental Technology Laboratory's Airborne Polarimetric Scanning Radiometer Measurements, which were made from the National Aeronautics and Space Administration P 3B aircraft during the campaign, were used primarily as a diagnostic tool to understand the comparative results and to suggest improvements to the AMSR-E ice concentration algorithm. Based on the AMSR-E/ETM+ comparisons, a good overall agreement with little bias ($sim$1%) for areas of first year and young sea ice was found. Areas of new ice production result in a negative bias of about 5% in the AMSR-E ice concentration retrievals, with a root mean square error of 8%. Some areas of deep snow also resulted in an underestimate of the ice concentration ($sim$10%). For all ice types combined and for the full range of ice concentrations, the bias ranged from 0% to 3%, and the rms errors ranged from 1% to 7%, depending on the region. The new-ice and deep-snow biases are expected to be reduced through an adjustment of the new-ice and ice-type C algorithm tie points. Copyright IEEE Numéro de notice : A2006-508 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2006.878445 En ligne : https://doi.org/10.1109/TGRS.2006.878445 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28232
in IEEE Transactions on geoscience and remote sensing > vol 44 n° 11 Tome 1 (November 2006) . - pp 3057 - 3069[article]Réservation
Réserver ce documentExemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-06111A RAB Revue Centre de documentation En réserve L003 Disponible Model-based prediction error uncertainty estimation for K-NN method / H.J. Kim in Remote sensing of environment, vol 104 n° 3 (15/10/2006)
![]()
[article]
Titre : Model-based prediction error uncertainty estimation for K-NN method Type de document : Article/Communication Auteurs : H.J. Kim, Auteur ; Erkki Tomppo, Auteur Année de publication : 2006 Article en page(s) : pp 257 - 263 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Betula (genre)
[Termes IGN] classification barycentrique
[Termes IGN] erreur moyenne quadratique
[Termes IGN] Finlande
[Termes IGN] image Landsat-TM
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Picea abies
[Termes IGN] Pinus (genre)
[Termes IGN] Populus (genre)
[Termes IGN] variogrammeRésumé : (Auteur) The k-nearest neighbour estimation method is one of the main tools used in multi-source forest inventories. It is a powerful non-parametric method for which estimates are easy to compute and relatively accurate. One downside of this method is that it lacks an uncertainty measure for predicted values and for areas of an arbitrary size. We present a method to estimate the prediction uncertainty based on the variogram model which derives the necessary formula for the k-nn method. A data application is illustrated for multi-source forest inventory data, and the results are compared at pixel level to the conventional RMSE method. We find that the variogram model-based method which is analytic, is competitive with the RMSE method. Numéro de notice : A2006-414 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2006.04.009 En ligne : https://doi.org/10.1016/j.rse.2006.04.009 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28138
in Remote sensing of environment > vol 104 n° 3 (15/10/2006) . - pp 257 - 263[article]Evaluation of the Oceansat-1 Multi-frequency Scanning Microwave Radiometer and its potential for soil moisture retrieval / J. Wen in International Journal of Remote Sensing IJRS, vol 27 n°18 - 19 - 20 (October 2006)
![]()
[article]
Titre : Evaluation of the Oceansat-1 Multi-frequency Scanning Microwave Radiometer and its potential for soil moisture retrieval Type de document : Article/Communication Auteurs : J. Wen, Auteur ; Thomas J. Jackson, Auteur ; R. Bindlish, Auteur ; Z.B. Su, Auteur Année de publication : 2006 Article en page(s) : pp 3781 - 3796 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] analyse de sensibilité
[Termes IGN] carte thématique
[Termes IGN] erreur systématique
[Termes IGN] Etats-Unis
[Termes IGN] humidité du sol
[Termes IGN] image IRS-MSMR
[Termes IGN] température de luminanceRésumé : (Auteur) The Multi-frequency Scanning Microwave Radiometer (MSMR) aboard the Indian Space Research Organization—Oceansat-1 platform measured land surface brightness temperature at a C-band frequency and provided an opportunity for exploring large-scale soil moisture retrieval during its two-year period of operation. These data may provide a valuable extension to the Scanning Multichannel Microwave Radiometer (SMMR) and the Advanced Microwave Scanning Radiometer (AMSR) since they covered a portion of the time period between the two missions. This investigation was one of the first to utilize the MSMR data for a land application and, as a result, several data quality issues had to be addressed. These included geolocation accuracy, calibration (particularly over land), erroneous data, and the significance of anthropogenic radio-frequency interference (RFI). Calibration of the low frequency channels was evaluated using inter-comparisons between the Tropical Rainfall Measuring Mission/Microwave Imager (TRMM/TMI) and the MSMR brightness temperatures. Biases (TMI TB>MSMR TB) of 3.4 and 3.6 K were observed over land for the MSMR 10.65 GHz horizontal and vertical polarization channels, respectively. These results suggested that additional calibration of the MSMR data was required. Comparisons between the MSMR measured brightness temperature and ground measured volumetric soil moisture collected during the South Great Plain experiment (SGP99) indicated that the lower frequency and horizontal polarization observations had higher sensitivity to soil moisture. Using a previously developed soil emission model, multi-temporal regional soil moisture distributions were retrieved for the continental United States. Comparisons between the MSMR based soil moisture and ground measured volumetric soil moisture indicated a standard error of estimate of 0.052 m3/m3. Copyright Taylor & Francis Numéro de notice : A2006-456 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160500075642 En ligne : https://doi.org/10.1080/01431160500075642 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28180
in International Journal of Remote Sensing IJRS > vol 27 n°18 - 19 - 20 (October 2006) . - pp 3781 - 3796[article]Réservation
Réserver ce documentExemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-06101 RAB Revue Centre de documentation En réserve L003 Disponible Geometric test field calibration of digital photogrammetric sensors / Eija Honkavaara in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 6 (September 2006)
![]()
[article]
Titre : Geometric test field calibration of digital photogrammetric sensors Type de document : Article/Communication Auteurs : Eija Honkavaara, Auteur ; E. Ahokas, Auteur ; Juha Hyyppä, Auteur ; et al., Auteur Année de publication : 2006 Article en page(s) : pp 387 - 399 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse comparative
[Termes IGN] caméra numérique
[Termes IGN] erreur systématique
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] étalonnage géométrique
[Termes IGN] photogrammétrie numérique
[Termes IGN] précision géométrique (imagerie)Résumé : (Auteur) Test field system calibration will be a fundamental part of the future photogrammetric production line. Accurate calibration and performance evaluations are necessary for fully assessing the stability and accuracy of digital sensing techniques. In this paper, a method of comprehensive geometric calibration in a test field has been developed and empirically tested using eight image blocks collected with three UltraCamD digital large format photogrammetric cameras. Permanent photogrammetric test fields form the basis of the method. Important components of the method are determination of system parameters, evaluation of systematic errors, and assessment of geometric accuracy. The results showed that UltraCamD images contained systematic deformations that could not be modeled with single lens additional parameter models. Good point determination accuracy was obtained despite the systematic errors ; the typical accuracy was 2–3 um in image space in the horizontal coordinates and 0.05–0.09 of the object distance in height. One of the cameras had significantly poorer performance. In the worst cases, the horizontal accuracy was 5 um in image space and the height accuracy was 0.18 of the object distance. The analog cameras gave better results than the UltraCamD, but the development of appropriate mathematical models for UltraCamD as well as improvements in digital sensors may change the situation in the near future. Numéro de notice : A2006-411 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2006.04.003 En ligne : https://doi.org/10.1016/j.isprsjprs.2006.04.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28135
in ISPRS Journal of photogrammetry and remote sensing > vol 60 n° 6 (September 2006) . - pp 387 - 399[article]Réservation
Réserver ce documentExemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-06061 SL Revue Centre de documentation Revues en salle Disponible Systematic effects in absolute chamber calibration of GPS antennas / Philipp Zeimetz in Geomatica, vol 60 n° 3 (September 2006)
PermalinkQuantifying spatial heterogeneity at the landscape scale using variogram models / S. Garrigues in Remote sensing of environment, vol 103 n° 1 (15 July 2006)
PermalinkCo-registration and inter-sensor comparison of MODIS and LANDSAT 7 ETM+ data aimed at NDVI calculation / P. Boccardo in Revue Française de Photogrammétrie et de Télédétection, n° 182 (Juin 2006)
PermalinkPermalinkDEM generation from SPOT-5 3-fold along track stereoscopic imagery using autocalibration / W. Kornus in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 3 (May 2006)
PermalinkMulti-image matching for DSM generation from Ikonos imagery / Li Zhang in ISPRS Journal of photogrammetry and remote sensing, vol 60 n° 3 (May 2006)
PermalinkPractical satellite navigation: part 3 error sources / Huibert-Jan Lekkerkerk in Geoinformatics, vol 9 n° 3 (01/05/2006)
PermalinkRepères de référence terrestres, rotation de la terre et télémétrie laser sur satellites / David Coulot in Géomatique expert, n° 50 (01/05/2006)
PermalinkUncovering the statistical and spatial characteristics of fine toposcale DEM error / Juha Oksanen in International journal of geographical information science IJGIS, vol 20 n° 4 (april 2006)
PermalinkGeolocation and pointing accuracy analysis for the WindSat sensor / W.E. Purdy in IEEE Transactions on geoscience and remote sensing, vol 44 n° 3 (March 2006)
PermalinkA global assessment of the STRM performance / E. Rodriguez in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 3 (March 2006)
PermalinkGPS + modernized GPS + Galileo signal timing biases / C. Hegarty in GPS world, vol 17 n° 3 (March 2006)
PermalinkCorrections for cluster-plot slop / Harry T. Valentine in Forest science, vol 52 n° 1 (February 2006)
PermalinkMulti-technique comparison of tropospheric zenith delays derived during the CONT02 campaign / Pascal Willis in Journal of geodesy, vol 79 n° 10-11 (February 2006)
PermalinkSpatiotriangulation with multisensor HR stereo-images / Thierry Toutin in IEEE Transactions on geoscience and remote sensing, vol 44 n° 2 (February 2006)
PermalinkSystematic errors in the Z-geocenter derived using satellite tracking data: a case study from SPOT-4 DORIS data in 1998 / Pascal Willis in Journal of geodesy, vol 79 n° 10-11 (February 2006)
PermalinkThe accuracy of grid digital elevation models linearly constructed from scattered sample data / F. Aguilar in International journal of geographical information science IJGIS, vol 20 n° 2 (february 2006)
PermalinkPermalinkOn the use of dimensioned measures of error to evaluate the performance of spatial interpolators / C.J. Willmot in International journal of geographical information science IJGIS, vol 20 n° 1 (january 2006)
PermalinkPermalink