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Storm event representation and analysis based on a directed spatiotemporal graph model / W. Liu in International journal of geographical information science IJGIS, vol 30 n° 5-6 (May - June 2016)
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Titre : Storm event representation and analysis based on a directed spatiotemporal graph model Type de document : Article/Communication Auteurs : W. Liu, Auteur ; Xingong Li, Auteur ; David A. Rahn, Auteur Année de publication : 2016 Article en page(s) : pp 948 - 969 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] dynamique spatiale
[Termes IGN] Etats-Unis
[Termes IGN] graphe
[Termes IGN] image radar
[Termes IGN] réflectivité
[Termes IGN] série temporelle
[Termes IGN] tempête
[Termes IGN] temps instantanéRésumé : (Auteur) Large amounts of time series of spatial snapshot data have been collected or generated for the monitoring and modeling of environmental systems. Those time series of data also provide the opportunity to study the movements and dynamics of many different natural phenomena. While the snapshot organization is conceptually simple and straightforward, it does not directly capture or represent the dynamic characteristics of the phenomena. This study presents computational methods to identify dynamic events from time series of spatial snapshots. Events are represented as directed spatiotemporal graphs to characterize their initiation, development, movement, and cessation. Graph-based algorithms are used to analyze the dynamics of the events. The method is applied to time series of high-resolution radar reflectivity images during one of the deadliest storm outbreaks that impacted 15 states of southeastern United States between 23 and 29 April 2011. As shown in this case study, convective storm events identified using our methods are consistent with previous studies, and our analysis confirms that the left split/merger occurs more than right split/merger in those convective storm events, which confirms theory, numerical simulations, and other observed case studies. While this study does not differentiate between storm modes, the method shows potential for capturing a more detailed climatology of precipitation characteristics. Numéro de notice : A2016-290 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2015.1081910 En ligne : https://doi.org/10.1080/13658816.2015.1081910 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80869
in International journal of geographical information science IJGIS > vol 30 n° 5-6 (May - June 2016) . - pp 948 - 969[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2016032 RAB Revue Centre de documentation En réserve L003 Disponible 079-2016031 RAB Revue Centre de documentation En réserve L003 Disponible Combined calibration method based on rational function model for the Chinese GF-1 wide-field-of-view imagery / Taoyang Wang in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 4 (April 2016)
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Titre : Combined calibration method based on rational function model for the Chinese GF-1 wide-field-of-view imagery Type de document : Article/Communication Auteurs : Taoyang Wang, Auteur ; Guo Zhang, Auteur ; Yonghua Jiang, Auteur Année de publication : 2016 Article en page(s) : pp 291 - 298 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] champ visuel
[Termes IGN] échantillonnage d'image
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] image GF-1
[Termes IGN] modèle par fonctions rationnelles
[Termes IGN] orientation interneRésumé : (auteur) The internal geometric distortion of charge-coupled-device (CCD) chips degrades the internal geometric accuracy of satellite images. Even if a large number of ground control points (GCPs) are used for geometric correction, the satellite images cannot always be used for direct mapping. Because of the current lack of core parameters for building a rigorous geometric model, this paper proposes a combined interior-orientation calibration method based on the rational function model (RFM) for multiple GF-1 wide-field-of-view (WFV) images of the same general scene. A polynomial model of look angles in the image space is chosen to compensate for the systemic error of CCD chips. After calibration for sensors 1 to 4, the orientation accuracy is improved to 0.4 pixels. Moreover, the residual error figures show no obvious trend. Other GF-1 WFV images are calibrated using the obtained interior-orientation parameters, and the improvement in their orientation accuracy is demonstrated to validate the effectiveness of the proposed method. Numéro de notice : A2016-181 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.82.4.291 En ligne : https://doi.org/10.14358/PERS.82.4.291 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80524
in Photogrammetric Engineering & Remote Sensing, PERS > vol 82 n° 4 (April 2016) . - pp 291 - 298[article]Comparative analysis of real-time precise point positioning zenith total delay estimates / F.A. Ahmed in GPS solutions, vol 20 n° 2 (April 2016)
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Titre : Comparative analysis of real-time precise point positioning zenith total delay estimates Type de document : Article/Communication Auteurs : F.A. Ahmed, Auteur ; Pavel Vaclavovic, Auteur ; Felix Norman Teferle, Auteur ; Jan Douša, Auteur ; R.M. Bingley, Auteur ; Denis Laurichesse, Auteur Année de publication : 2016 Article en page(s) : pp 187 - 199 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse comparative
[Termes IGN] erreur moyenne
[Termes IGN] erreur systématique
[Termes IGN] modèle atmosphérique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] retard troposphérique zénithal
[Termes IGN] temps réel
[Vedettes matières IGN] Traitement de données GNSSRésumé : (Auteur) The continuous evolution of global navigation satellite systems (GNSS) meteorology has led to an increased use of associated observations for operational modern low-latency numerical weather prediction (NWP) models, which assimilate GNSS-derived zenith total delay (ZTD) estimates. The development of NWP models with faster assimilation cycles, e.g., 1-h assimilation cycle in the rapid update cycle NWP model, has increased the interest of the meteorological community toward sub-hour ZTD estimates. The suitability of real-time ZTD estimates obtained from three different precise point positioning software packages has been assessed by comparing them with the state-of-the-art IGS final troposphere product as well as collocated radiosonde (RS) observations. The ZTD estimates obtained by BNC2.7 show a mean bias of 0.21 cm, and those obtained by the G-Nut/Tefnut software library show a mean bias of 1.09 cm to the IGS final troposphere product. In comparison with the RS-based ZTD, the BNC2.7 solutions show mean biases between 1 and 2 cm, whereas the G-Nut/Tefnut solutions show mean biases between 2 and 3 cm with the RS-based ZTD, and the ambiguity float and ambiguity fixed solutions obtained by PPP-Wizard have mean biases between 6 and 7 cm with the references. The large biases in the time series from PPP-Wizard are due to the fact that this software has been developed for kinematic applications and hence does not apply receiver antenna eccentricity and phase center offset (PCO) corrections on the observations. Application of the eccentricity and PCO corrections to the a priori coordinates has resulted in a 66 % reduction of bias in the PPP-Wizard solutions. The biases are found to be stable over the whole period of the comparison, which are criteria (rather than the magnitude of the bias) for the suitability of ZTD estimates for use in NWP nowcasting. A millimeter-level impact on the ZTD estimates has also been observed in relation to ambiguity resolution. As a result of a comparison with the established user requirements for NWP nowcasting, it was found that both the G-Nut/Tefnut solutions and one of the BNC2.7 solutions meet the threshold requirements, whereas one of the BNC2.7 solution and both the PPP-Wizard solutions currently exceed this threshold. Numéro de notice : A2016-611 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-014-0427-z En ligne : http://dx.doi.org/10.1007/s10291-014-0427-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81810
in GPS solutions > vol 20 n° 2 (April 2016) . - pp 187 - 199[article]Forest above ground biomass inversion by fusing GLAS with optical remote sensing data / Xiaohuan Xi in ISPRS International journal of geo-information, vol 5 n° 4 (April 2016)
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Titre : Forest above ground biomass inversion by fusing GLAS with optical remote sensing data Type de document : Article/Communication Auteurs : Xiaohuan Xi, Auteur ; Tingting Han, Auteur ; Cheng Wang, Auteur ; et al., Auteur Année de publication : 2016 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] biomasse aérienne
[Termes IGN] classification par réseau neuronal
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] données ICEsat
[Termes IGN] forêt
[Termes IGN] hauteur de la végétation
[Termes IGN] image Landsat-TM
[Termes IGN] image optique
[Termes IGN] image Terra-MODIS
[Termes IGN] Leaf Area Index
[Termes IGN] MNS ASTER
[Termes IGN] régression
[Termes IGN] Yunnan (Chine)Résumé : (auteur) Forest biomass is an important parameter for quantifying and understanding biological and physical processes on the Earth’s surface. Rapid, reliable, and objective estimations of forest biomass are essential to terrestrial ecosystem research. The Geoscience Laser Altimeter System (GLAS) produced substantial scientific data for detecting the vegetation structure at the footprint level. This study combined GLAS data with MODIS/BRDF (Bidirectional Reflectance Distribution Function) and ASTER GDEM data to estimate forest aboveground biomass (AGB) in Xishuangbanna, Yunnan Province, China. The GLAS waveform characteristic parameters were extracted using the wavelet method. The ASTER DEM was used to compute the terrain index for reducing the topographic influence on the GLAS canopy height estimation. A neural network method was applied to assimilate the MODIS BRDF data with the canopy heights for estimating continuous forest heights. Forest leaf area indices (LAIs) were derived from Landsat TM imagery. A series of biomass estimation models were developed and validated using regression analyses between field-estimated biomass, canopy height, and LAI. The GLAS-derived canopy heights in Xishuangbanna correlated well with the field-estimated AGB (R2 = 0.61, RMSE = 52.79 Mg/ha). Combining the GLAS estimated canopy heights and LAI yielded a stronger correlation with the field-estimated AGB (R2 = 0.73, RMSE = 38.20 Mg/ha), which indicates that the accuracy of the estimated biomass in complex terrains can be improved significantly by integrating GLAS and optical remote sensing data. Numéro de notice : A2016-820 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi5040045 En ligne : https://doi.org/10.3390/ijgi5040045 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82625
in ISPRS International journal of geo-information > vol 5 n° 4 (April 2016)[article]The attenuation of retroreflective signatures on surface soils / Robyn A. Barbato in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 4 (April 2016)
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Titre : The attenuation of retroreflective signatures on surface soils Type de document : Article/Communication Auteurs : Robyn A. Barbato, Auteur ; Karen L. Foley, Auteur ; Adam Lewinter, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 283 - 289 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse de données
[Termes IGN] données lidar
[Termes IGN] matière organique
[Termes IGN] réflectance du sol
[Termes IGN] rétroréflecteur
[Termes IGN] signature polarimétriqueRésumé : (auteur) Soil parameters such as water potential, temperature, organic matter (OM), and particle size distribution influence biological activity and collectively define the state of soils, yet these properties are typically described through time-intensive, ground-based sampling efforts. To improve our understanding of soils through stand-off sensing techniques, Light Detection and Ranging was used to monitor the signature of retroreflective beads embedded in polymeric agents on four soils. Our goal was to generate probability density functions (PDFs) for stochastic predictions of the persistence of this signature through time. Our findings showed that the PDFs of the reflected signal between target and background soils became nearly indistinguishable after five months and that OM, nitrogen content, cation exchange capacity, and pH related to signature decline. This approach, while developed using polymer-bound retroreflectors, will serve as a framework where a signature-emitter is left in or on soil and differentially influenced by terrain, weather, and soil processes. Numéro de notice : A2016-180 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.82.4.283 En ligne : https://doi.org/10.14358/PERS.82.4.283 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80523
in Photogrammetric Engineering & Remote Sensing, PERS > vol 82 n° 4 (April 2016) . - pp 283 - 289[article]14 years of GPS tropospheric delays in the French–Italian border region : comparisons and first application in a case study / Domenico Sguerso in Applied geomatics, vol 8 n° 1 (March 2016)
PermalinkCorrection of terrestrial LiDAR intensity channel using Oren–Nayar reflectance model: An application to lithological differentiation / Dario Carrea in ISPRS Journal of photogrammetry and remote sensing, vol 113 (March 2016)
PermalinkDetermination of differential code biases with multi-GNSS observations / Ningbo Wang in Journal of geodesy, vol 90 n° 3 (March 2016)
PermalinkEffect of tree location on mitigating parking lot insolation / Ivana Bajsanski in Computers, Environment and Urban Systems, vol 56 (March 2016)
PermalinkNoise simulation and correction in synthetic airborne TIR Data for mineral quantification / Christoph Hecker in IEEE Transactions on geoscience and remote sensing, vol 54 n° 3 (March 2016)
PermalinkToward operational compensation of ionospheric effects in SAR interferograms: the split-spectrum method / Giorgio Gomba in IEEE Transactions on geoscience and remote sensing, vol 54 n° 3 (March 2016)
PermalinkAn enhanced algorithm to estimate BDS satellite’s differential code biases / Chuang Shi in Journal of geodesy, vol 90 n° 2 (February 2016)
PermalinkGeo-localization using volumetric representations of overhead imagery / Ozge C. Ozcanli in International journal of computer vision, vol 116 n° 3 (February 2016)
PermalinkIonospheric corrections for single-frequency tracking of GNSS satellites by VLBI based on co-located GNSS / Benjamin Männel in Journal of geodesy, vol 90 n° 2 (February 2016)
PermalinkIs waveform worth it? A comparison of LiDAR approaches for vegetation and landscape characterization / Karen Anderson in Remote sensing in ecology and conservation, vol 2 n° 1 (February 2016)
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