Descripteur
Documents disponibles dans cette catégorie (136)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
Ionospheric tomography using GNSS: multiplicative algebraic reconstruction technique applied to the area of Brazil / Fabricio Dos Santos Prol in GPS solutions, vol 20 n° 4 (October 2016)
[article]
Titre : Ionospheric tomography using GNSS: multiplicative algebraic reconstruction technique applied to the area of Brazil Type de document : Article/Communication Auteurs : Fabricio Dos Santos Prol, Auteur ; Paulo de Oliveira Camargo, Auteur Année de publication : 2016 Article en page(s) : pp 807 - 814 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Brésil
[Termes IGN] code GNSS
[Termes IGN] International Reference Ionosphere
[Termes IGN] modèle ionosphérique
[Termes IGN] phase GNSS
[Termes IGN] récepteur GNSS
[Termes IGN] teneur totale en électrons
[Termes IGN] tomographie par GPSRésumé : (Auteur) Experimental analysis was performed using multiplicative algebraic reconstruction technique (MART) to map the ionosphere over Brazil. Code and phase observations from the global navigation satellite system (GNSS) together with the international reference ionosphere (IRI) enabled the estimation of ionospheric profiles and total electron content (TEC) over the entire region. Twenty-four days of data collected from existing ground-based GNSS receivers during the recent solar maximum period were used to analyze the performance of the MART algorithm. The results were compared with four ionosondes. It was demonstrated that MART estimated the electron density peak with the same degree of accuracy as the IRI model in regions with appropriate geometrical coverage by GNSS receivers for tomographic reconstruction. In addition, the slant TEC, as estimated with MART, presented lower root-mean-square error than the TEC calculated by ionospheric maps available from the International GNSS Service (IGS). Furthermore, the daily variations of the ionosphere were better represented with the algebraic techniques, compared to the IRI model and IGS maps, enabling a correlation of the elevation of the ionosphere at higher altitudes with the equatorial ionization anomaly intensification. The tomographic representations also enabled the detection of high vertical gradients at the same instants in which ionospheric irregularities were evident. Numéro de notice : A2016--030 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0490-0 En ligne : http://dx.doi.org/10.1007/s10291-015-0490-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83932
in GPS solutions > vol 20 n° 4 (October 2016) . - pp 807 - 814[article]Using a regional numerical weather prediction model for GNSS positioning over Brazil / Daniele Barroca Marra Alves in GPS solutions, vol 20 n° 4 (October 2016)
[article]
Titre : Using a regional numerical weather prediction model for GNSS positioning over Brazil Type de document : Article/Communication Auteurs : Daniele Barroca Marra Alves, Auteur ; Luiz Fernando Sapucci, Auteur ; Haroldo Antonio Marques, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 677 - 685 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Amazonie
[Termes IGN] Brésil
[Termes IGN] modèle de simulation
[Termes IGN] modèle météorologique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] propagation troposphérique
[Termes IGN] station GNSS
[Termes IGN] teneur en vapeur d'eau
[Termes IGN] troposphèreRésumé : (Auteur) The global navigation satellite system (GNSS) can provide centimeter positioning accuracy at low costs. However, in order to obtain the desired high accuracy, it is necessary to use high-quality atmospheric models. We focus on the troposphere, which is an important topic of research in Brazil where the tropospheric characteristics are unique, both spatially and temporally. There are dry regions, which lie mainly in the central part of the country. However, the most interesting area for the investigation of tropospheric models is the wet region which is located in the Amazon forest. This region substantially affects the variability of humidity over other regions of Brazil. It provides a large quantity of water vapor through the humidity convergence zone, especially for the southeast region. The interconnection and large fluxes of water vapor can generate serious deficiencies in tropospheric modeling. The CPTEC/INPE (Center for Weather Forecasting and Climate Studies/Brazilian Institute for Space Research) has been providing since July 2012 a numerical weather prediction (NWP) model for South America, known as Eta. It has yield excellent results in weather prediction but has not been used in GNSS positioning. This NWP model was evaluated in precise point positioning (PPP) and network-based positioning. Concerning PPP, the best positioning results were obtained for the station SAGA, located in Amazon region. Using the NWP model, the 3D RMS are less than 10 cm for all 24 h of data, whereas the values reach approximately 60 cm for the Hopfield model. For network-based positioning, the best results were obtained mainly when the tropospheric characteristics are critical, in which case an improvement of up to 7.2 % was obtained in 3D RMS using NWP models. Numéro de notice : A2016--028 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0477-x En ligne : http://dx.doi.org/10.1007/s10291-015-0477-x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83930
in GPS solutions > vol 20 n° 4 (October 2016) . - pp 677 - 685[article]Floristic composition and across-track reflectance gradient in Landsat images over Amazonian forests / Javier Muro in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)
[article]
Titre : Floristic composition and across-track reflectance gradient in Landsat images over Amazonian forests Type de document : Article/Communication Auteurs : Javier Muro, Auteur ; Jasper Van Doninck, Auteur ; Hanna Tuomisto, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 361 - 372 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Amazonie
[Termes IGN] angle de visée
[Termes IGN] anisotropie
[Termes IGN] Brésil
[Termes IGN] composition floristique
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] forêt primaire
[Termes IGN] forêt tropicale
[Termes IGN] gradient
[Termes IGN] image Landsat-ETM+
[Termes IGN] Pérou
[Termes IGN] réflectance végétaleRésumé : (Auteur) Remotely sensed image interpretation or classification of tropical forests can be severely hampered by the effects of the bidirectional reflection distribution function (BRDF). Even for narrow swath sensors like Landsat TM/ETM+, the influence of reflectance anisotropy can be sufficiently strong to introduce a cross-track reflectance gradient. If the BRDF could be assumed to be linear for the limited swath of Landsat, it would be possible to remove this gradient during image preprocessing using a simple empirical method. However, the existence of natural gradients in reflectance caused by spatial variation in floristic composition of the forest can restrict the applicability of such simple corrections. Here we use floristic information over Peruvian and Brazilian Amazonia acquired through field surveys, complemented with information from geological maps, to investigate the interaction of real floristic gradients and the effect of reflectance anisotropy on the observed reflectances in Landsat data. In addition, we test the assumption of linearity of the BRDF for a limited swath width, and whether different primary non-inundated forest types are characterized by different magnitudes of the directional reflectance gradient. Our results show that a linear function is adequate to empirically correct for view angle effects, and that the magnitude of the across-track reflectance gradient is independent of floristic composition in the non-inundated forests we studied. This makes a routine correction of view angle effects possible. However, floristic variation complicates the issue, because different forest types have different mean reflectances. This must be taken into account when deriving the correction function in order to avoid eliminating natural gradients. Numéro de notice : A2016-788 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2016.06.016 En ligne : https://doi.org/10.1016/j.isprsjprs.2016.06.016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82503
in ISPRS Journal of photogrammetry and remote sensing > vol 119 (September 2016) . - pp 361 - 372[article]Spatio-temporal change detection from multidimensional arrays: Detecting deforestation from MODIS time series / Meng Lu in ISPRS Journal of photogrammetry and remote sensing, vol 117 (July 2016)
[article]
Titre : Spatio-temporal change detection from multidimensional arrays: Detecting deforestation from MODIS time series Type de document : Article/Communication Auteurs : Meng Lu, Auteur ; Edzer J. Pebesma, Auteur ; Alber Sanchez, Auteur ; Jan Verbesselt, Auteur Année de publication : 2016 Article en page(s) : pp 227 – 236 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Amazonie
[Termes IGN] Brésil
[Termes IGN] corrélation automatique de points homologues
[Termes IGN] déboisement
[Termes IGN] détection de changement
[Termes IGN] image Aqua-MODIS
[Termes IGN] image Terra-MODIS
[Termes IGN] points de rupture
[Termes IGN] série temporelleRésumé : (auteur) Growing availability of long-term satellite imagery enables change modeling with advanced spatio-temporal statistical methods. Multidimensional arrays naturally match the structure of spatio-temporal satellite data and can provide a clean modeling process for complex spatio-temporal analysis over large datasets. Our study case illustrates the detection of breakpoints in MODIS imagery time series for land cover change in the Brazilian Amazon using the BFAST (Breaks For Additive Season and Trend) change detection framework. BFAST includes an Empirical Fluctuation Process (EFP) to alarm the change and a change point time locating process. We extend the EFP to account for the spatial autocorrelation between spatial neighbors and assess the effects of spatial correlation when applying BFAST on satellite image time series. In addition, we evaluate how sensitive EFP is to the assumption that its time series residuals are temporally uncorrelated, by modeling it as an autoregressive process. We use arrays as a unified data structure for the modeling process, R to execute the analysis, and an array database management system to scale computation. Our results point to BFAST as a robust approach against mild temporal and spatial correlation, to the use of arrays to ease the modeling process of spatio-temporal change, and towards communicable and scalable analysis. Numéro de notice : A2016-586 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2016.03.007 En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2016.03.007 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81727
in ISPRS Journal of photogrammetry and remote sensing > vol 117 (July 2016) . - pp 227 – 236[article]Towards a system combining SAR and optical Sentinel data to monitor gold mining in the Guiana shield / Mathieu Rahm (2016)
Titre : Towards a system combining SAR and optical Sentinel data to monitor gold mining in the Guiana shield Type de document : Article/Communication Auteurs : Mathieu Rahm, Auteur ; Cédric Lardeux, Auteur ; Pierre-Louis Frison , Auteur ; et al., Auteur Editeur : Paris : Agence Spatiale Européenne ASE / European Space Agency ESA Année de publication : 2016 Conférence : LPS 2016, ESA Living Planet Symposium 09/05/2016 13/05/2016 Prague République tchèque programme sans actes Importance : 60 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] Brésil
[Termes IGN] déboisement
[Termes IGN] fusion d'images
[Termes IGN] Guyana
[Termes IGN] Guyane (département français)
[Termes IGN] image Sentinel-MSI
[Termes IGN] image Sentinel-SAR
[Termes IGN] mine d'or
[Termes IGN] pollution des eaux
[Termes IGN] SurinameRésumé : (auteur) Included in the larger Guiana Shield ecosystem, Suriname, Guyana, French Guiana and the Brazilian state of Amapá possess one of the largest continuous tracts of pristine forest in the world. Under little threat until fifteen years ago, deforestation and forest degradation are of increasing concern in the region. Gold mining activities driven by the sustained increase of gold price has experienced a significant boom and represents nowadays one of the main driver. The pollution of rivers and streams by mercury used in small-scale gold mining is also expanding, which increases risks to local population health and freshwater biodiversity. In 2010, the French National Forest Office (ONF) showed by using optical satellite images at medium and high resolution (HR) that gold mining activities’ impacts on forest cover and freshwater increased approximately by a factor three in the region between 2001 and 2008. More recently, Alvarez-Berríos et al. (2015) pointed out a sustained acceleration of deforestation caused by gold mining in the Guiana shield between 2007 and 2013. However, this study which was performed using low resolution data at the scale of South America has limited capacity to detect gold mining, especially in the high forest cover of Guiana Shield where small- and medium-scale operations account for most of the deforestation. To overcome this limitation, the REDD+ for the Guiana Shield project conducted a study co-funded by WWF Guianas to update for 2014 the ONF 2001-2008 results, using optical multi-sensors data at medium and high resolution. The study was carried out following a unique collaborative and participatory approach involving a team of experts from the forestry and environmental services of each territory, namely SEMA (Amapá-Brazil), ONF (French Guiana-France), GFC (Guyana), and SBB (Suriname). The results confirmed the rapid expansion of the activity in the region where more than 92,000 ha were newly deforested between 2008 and 2014, compared to approximately 46,000 ha during the period 2001-2008. In 2014, more than 9,000 km of waterways were in direct contact with mining sites, which is approximately 6.5 times more than in 2001. Although a reliable, accurate and robust regional methodology has been developed and operationally implemented, the frequent and widespread cloud cover of the Guianan moist forest region represents a challenge for the use of optical HR data. The need to process time series of satellite images in most areas to reduce cloud cover is time-consuming. Despite processing more than two hundreds images, 3.6% of the study area remained masked by clouds. The recent free access to SAR HR Sentinel-1 data offers great opportunities to improve the process. SAR sensors can peer through clouds and their sensitivity to soil moisture can help to better detect small-scale mining sites. Therefore, the REDD+ for the Guiana Shield project has started to build capacities in the region on SAR image interpretation and processing using the Sentinel Application Platform (SNAP). A first mosaic of Sentinel-1 data covering Suriname, Guyana, French Guiana and the Brazilian state of Amapá has been created and automated pre-processing steps have been developed. The integration of Sentinel-1 data in the regional gold mining monitoring system has been successfully tested in four study sites, one in each country. The coming free access to optical HR Sentinel-2 data opens even more perspectives towards the development of cost-effective monitoring systems in the region, especially valuable in the context of REDD+. This paper first presents the results of the impact of gold mining activities on the forest cover and freshwater for 2014 and shows the evolution since 2001. Secondly, it provides the first outcomes towards the development of time- and cost-efficient forest monitoring systems in the region. Numéro de notice : C2016-058 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : http://lps16.esa.int/page_session187.php#1306p Format de la ressource électronique : URL abstract Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91912 Documents numériques
en open access
Towards a System Combining SAR... (final report) - pdf auteurAdobe Acrobat PDF Geodesign in parametric modeling of urban landscape / Ana clara Mourão Moura in Cartography and Geographic Information Science, Vol 42 n° 4 (September 2015)PermalinkHow much do we know about the endangered Atlantic Forest? Reviewing nearly 70 years of information on tree community surveys / Renato A.F. de Lima in Biodiversity & Conservation, vol 24 n° 9 (September 2015)PermalinkTélédétection pour l'agriculture de précision par caméra hyperspectrale miniature / D. Constantin in Géomatique suisse, vol 113 n° 9 (septembre 2015)PermalinkUse of Landsat and Corona data for mapping forest cover change from the mid-1960s to 2000s: Case studies from the Eastern United States and Central Brazil / Dan-Xia Song in ISPRS Journal of photogrammetry and remote sensing, vol 103 (May 2015)PermalinkBayesian belief networks as a versatile method for assessing uncertainty in land-change modeling / Carsten Krüger in International journal of geographical information science IJGIS, vol 29 n° 1 (January 2015)PermalinkDétermination GNSS de bornes de la frontière de la Guyane française dans le cadre du « raid des 7 bornes », version 1 / Samuel Branchu (2015)PermalinkExterior orientation of hyperspectral frame images collected with UAV for forest applications / Adilson Berveglieri (2015)PermalinkPermalinkSTARS : A new method for multitemporal remote sensing / Marcio Pupin Mello in IEEE Transactions on geoscience and remote sensing, vol 51 n° 4 Tome 1 (April 2013)PermalinkLe Jari / François-Michel Le Tourneau (2013)PermalinkQuantifying deforestation in the Brazilian Amazon using advanced land observing satellite phased array L-band synthetic aperture radar (ALOS PALSAR) and shuttle imaging radar (SIR)-C data / M. Rahman in Geocarto international, vol 27 n° 6 (October 2012)PermalinkCombined use of Quickbird and lidar data for mapping a urban environment / N.B. Da Luz in Revue Française de Photogrammétrie et de Télédétection, n° 198 - 199 (Septembre 2012)PermalinkContributions of remote sensing to the cartographic development of the Brazilian territory: an introductory overview / M.C. Bonato Brandalize in Revue Française de Photogrammétrie et de Télédétection, n° 198 - 199 (Septembre 2012)PermalinkFusion d'informations issue de la télédétection radar pour l'observation de déplacements dans la région de Manaus (Amazonie) / F.L. Ramos in Revue Française de Photogrammétrie et de Télédétection, n° 198 - 199 (Septembre 2012)PermalinkUtilisation de la télédétection et de données socio-économiques et écologiques pour comprendre l'impact des dynamiques de l'occupation des sols à Pacaja (Brésil) / J. Oszwald in Revue Française de Photogrammétrie et de Télédétection, n° 198 - 199 (Septembre 2012)PermalinkApplication of time series Landsat images to examining land-use / land-cover dynamic change / Dong Lu in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 7 (July 2012)PermalinkApplication of time series Landsat images to examining land-use/land-cover dynamic change / Dong Lu in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 7 (July 2012)PermalinkDetection of large-scale forest canopy change in pan-tropical humid forests 2000–2009 with the seawinds Ku-band scatterometer / S. Frolking in IEEE Transactions on geoscience and remote sensing, vol 50 n° 7 Tome 1 (July 2012)PermalinkEstimating tropical forest biomass with a combination of SAR image texture and Landsat TM data: An assessment of predictions between regions / M. Cutler in ISPRS Journal of photogrammetry and remote sensing, vol 70 (June 2012)PermalinkSpatial patterns and eco-epidemiological systems – part 1: multi-scale spatial modelling of the occurrence of Chagas disease insect vectors / Emmanuel Roux in Geospatial Health, vol 6 n° 1 (November 2011)PermalinkSpatial patterns and eco-epidemiological systems – part 2: multi-scale spatial modelling of the occurrence of Chagas disease insect vectors / Emmanuel Roux in Geospatial Health, vol 6 n° 1 (November 2011)PermalinkAprès Copenhague, la déforestation en question / Fabienne Tisserand in Le Bois International : l'officiel du bois [édition verte], vol 2010 n° 13 (03 avril 2010)PermalinkLes marchés du carbone forestier : quelle est la place de la forêt dans les marchés du carbone ? Quelles sont les tendances à anticiper ? Comment financer un projet et vendre des crédits ? / Clément Chenost (2010)PermalinkDéfinition des risques encourus par des pylônes électriques au moyen de l'évolution de l'érosion / G. Clasen Wosny in XYZ, n° 121 (décembre 2009 - février 2010)PermalinkDiscrimination of agricultural crops in a tropical semi-arid region of Brazil based on L-band polarimetric airborne SAR data / W. Silva in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)PermalinkA high resolution orthomosaic in Brazil / N. Parada in Geoinformatics, vol 12 n° 5 (01/07/2009)PermalinkInfluence of macroscale and microscale surface roughness on multi-beam RADARSAT-1 data: implications for geological mapping in the Curaçá Valley, Brazil / W.R. Paradella in Photo interprétation, European journal of applied remote sensing, vol 45 n° 2 (juin 2009)PermalinkAtlas des migrations nord-brésiliennes vers la Guyane, Projet ANR / Maeve De France (2009)PermalinkFeature reduction using a singular value decomposition for the iterative guided spectral class rejection hybrid classifier / R. Philipps in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 1 (January - February 2009)PermalinkDéveloppement durable et lutte contre la déforestation en Amazonie brésilienne : le bon, le mauvais et le pire / Claudia Azevedo-Ramos in Unasylva, n° 230 (2008-1)PermalinkModel investigation about the potential of C-band SAR in herbaceous wetlands flood monitoring / F. Grings in International Journal of Remote Sensing IJRS, vol 29 n° 17-18 (September 2008)PermalinkUsing neural networks and cellular automata for modelling intra-urban land-use dynamics / C.M. Almeida in International journal of geographical information science IJGIS, vol 22 n° 8-9 (august 2008)PermalinkUn petit maillon de la filière bois s'exporte au Brésil / Fabienne Tisserand in Le Bois International : l'officiel du bois [édition verte], vol 2008 n° 9 (1er et 8 mars 2008)PermalinkLand-cover classification in the Brazilian Amazon with the integration of Landsat ETM+ and Radarsat data / Dong Lu in International Journal of Remote Sensing IJRS, vol 28 n°23-24 (December 2007)PermalinkMultitemporel fuzzy classification model based on class transition possibilities / G.L.A. Mota in ISPRS Journal of photogrammetry and remote sensing, vol 62 n° 3 (August 2007)PermalinkGlobal and local spatial indices of urban segregation / F.F. Feitosa in International journal of geographical information science IJGIS, vol 21 n° 3-4 (march - april 2007)PermalinkSageo 2006 : du spatial au spatio-temporel / Françoise de Blomac in SIG la lettre, n° 80 (octobre 2006)PermalinkLand-cover mapping in the Brazilian amazon using SPOT-4 Vegetation data and machine learning classification methods / João M.B. Carreiras in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 8 (August 2006)PermalinkAn empirical investigation of cross-sensor relationships of NDVI and red/near-infrared reflectance using EO-1 Hyperion data / T. Miura in Remote sensing of environment, vol 100 n° 2 (30 January 2006)PermalinkRelating SAR image texture to the biomass of regenerating tropical forests / T.M. Kuplich in International Journal of Remote Sensing IJRS, vol 26 n° 21 (November 2005)PermalinkSPOT-4 Vegetation multi-temporal compositing for land cover change studies over tropical regions / João M.B. Carreiras in International Journal of Remote Sensing IJRS, vol 26 n° 7 (April 2005)PermalinkClassification orientée objet de la perméabilité des sols en zone urbaine à l'aide d'imagerie très haute résolution et de données laser scanner à Curitiba (Brésil) / A. Karsenty in XYZ, n° 102 (mars - mai 2005)PermalinkGIS and remote sensing as tools for the simulation of urban land-use change / C.M. Almeida in International Journal of Remote Sensing IJRS, vol 26 n° 4 (February 2005)PermalinkMapping regional land cover with MODIS data for biological conservation: examples from the greater Yellowstone ecosystem, USA and PARA state, Brazil / K.J. Wessels in Remote sensing of environment, vol 92 n° 1 (15 July 2004)PermalinkSur la frontière Guyane - Brésil : 1956 - 1961 - 1962 - 1991 : souvenirs et carnets de mission de Jean Hurault et Pierre Frenay (Bulletin de Cahiers historiques de l'IGN) / Pierre PlanquesPermalink