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Does long-term GPS in the Western Alps finally confirm earthquake mechanisms? / Andrea Walpersdorf in Tectonics, vol 37 n° 10 (October 2018)
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Titre : Does long-term GPS in the Western Alps finally confirm earthquake mechanisms? Type de document : Article/Communication Auteurs : Andrea Walpersdorf, Auteur ; L. Pinget, Auteur ; P. Vernant, Auteur ; C. Sue, Auteur ; A. Deprez, Auteur ; et al., Auteur ; Olivier Bock , Auteur ; Thierry Duquesnoy
, Auteur ; Romain Fagès
, Auteur ; Bruno Garayt
, Auteur ; Elise-Rachel Mathis
, Auteur ; Thierry Person
, Auteur ; Sébastien Saur
, Auteur
Année de publication : 2018 Projets : RESIF-CORE / Vergne, Jérôme Article en page(s) : pp 3721 - 3737 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Alpes occidentales
[Termes IGN] coordonnées GPS
[Termes IGN] séisme
[Termes IGN] série temporelleRésumé : (auteur) The availability of GPS survey data spanning 22 years, along with several independent velocity solutions including up to 16 years of permanent GPS data, presents a unique opportunity to search for persistent (and thus reliable) deformation patterns in the Western Alps, which in turn allow a reinterpretation of the active tectonics of this region. While GPS velocities are still too uncertain to be interpreted on an individual basis, the analysis of range-perpendicular GPS velocity profiles clearly highlights zones of extension in the center of the belt (15.3 to 3.1 nanostrain/year from north to south), with shortening in the forelands. The contrasting geodetic deformation pattern is coherent with earthquake focal mechanisms and related strain/stress patterns over the entire Western Alps. The GPS results finally provide a reliable and robust quantification of the regional strain rates. The observed vertical motions of 2.0 to 0.5 mm/year of uplift from north to south in the core of the Western Alps is interpreted to result from buoyancy forces related to postglacial rebound, erosional unloading, and/or viscosity anomalies in the crustal and lithospheric root. Spatial decorrelation between vertical and horizontal (seismicity related) deformation calls for a combination of processes to explain the complex present-day dynamics of the Western Alps. Numéro de notice : A2018-681 Affiliation des auteurs : IGN+Ext (2012-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2018TC005054 Date de publication en ligne : 03/09/2018 En ligne : https://doi.org/10.1029/2018TC005054 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98132
in Tectonics > vol 37 n° 10 (October 2018) . - pp 3721 - 3737[article]Estimating forest canopy cover in black locust (Robinia pseudoacacia L.) plantations on the loess plateau using random forest / Qingxia Zhao in Forests, vol 9 n° 10 (October 2018)
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Titre : Estimating forest canopy cover in black locust (Robinia pseudoacacia L.) plantations on the loess plateau using random forest Type de document : Article/Communication Auteurs : Qingxia Zhao, Auteur ; Fei Wang, Auteur ; Jun Zhao, Auteur ; Jingjing Zhou, Auteur ; et al., Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] canopée
[Termes IGN] Chine
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] détection d'arbres
[Termes IGN] Enhanced vegetation index
[Termes IGN] image multibande
[Termes IGN] image panchromatique
[Termes IGN] loess
[Termes IGN] matrice de co-occurrence
[Termes IGN] plantation forestière
[Termes IGN] régression
[Termes IGN] Robinia pseudoacacia
[Termes IGN] Soil Adjusted Vegetation IndexRésumé : (Auteur) The forest canopy is the medium for energy and mass exchange between forest ecosystems and the atmosphere. Remote sensing techniques are more efficient and appropriate for estimating forest canopy cover (CC) than traditional methods, especially at large scales. In this study, we evaluated the CC of black locust plantations on the Loess Plateau using random forest (RF) regression models. The models were established using the relationships between digital hemispherical photograph (DHP) field data and variables that were calculated from satellite images. Three types of variables were calculated from the satellite data: spectral variables calculated from a multispectral image, textural variables calculated from a panchromatic image (Tpan) with a 15 × 15 window size, and textural variables calculated from spectral variables (TB+VIs) with a 9 × 9 window size. We compared different mtry and ntree values to find the most suitable parameters for the RF models. The results indicated that the RF model of spectral variables explained 57% (root mean square error (RMSE) = 0.06) of the variability in the field CC data. The soil-adjusted vegetation index (SAVI) and enhanced vegetation index (EVI) were more important than other spectral variables. The RF model of Tpan obtained higher accuracy (R2 = 0.69, RMSE = 0.05) than the spectral variables, and the grey level co-occurrence matrix-based texture measure—Correlation (COR) was the most important variable for Tpan. The most accurate model was obtained from the TB+VIs (R2 = 0.79, RMSE = 0.05), which combined spectral and textural information, thus providing a significant improvement in estimating CC. This model provided an effective approach for detecting the CC of black locust plantations on the Loess Plateau. Numéro de notice : A2018-477 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/f9100623 Date de publication en ligne : 10/10/2018 En ligne : https://doi.org/10.3390/f9100623 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91178
in Forests > vol 9 n° 10 (October 2018)[article]Estimating the leaf area of an individual tree in urban areas using terrestrial laser scanner and path length distribution model / Ronghai Hu in ISPRS Journal of photogrammetry and remote sensing, vol 144 (October 2018)
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Titre : Estimating the leaf area of an individual tree in urban areas using terrestrial laser scanner and path length distribution model Type de document : Article/Communication Auteurs : Ronghai Hu, Auteur ; Elena Bournez, Auteur ; Shiyu Cheng, Auteur ; Hailan Jiang, Auteur ; et al., Auteur Année de publication : 2018 Article en page(s) : pp 357 - 368 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] arbre urbain
[Termes IGN] densité du feuillage
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] feuille (végétation)
[Termes IGN] longueur de trajet
[Termes IGN] semis de pointsRésumé : (Auteur) Urban leaf area measurement is crucial to properly determining the effect of urban trees on micro-climate regulation, heat island effect, building cooling, air quality improvement, and ozone formation. Previous works on the leaf area measurement have mainly focused on the stand level, although the presence of individual trees is more common than forests in urban areas. The only feasible ways for an operational non-destructive leaf area measurement, namely, optical indirect methods, are mostly limited in urban areas because light path is constantly intercepted by surrounding buildings or other objects. A terrestrial laser scanner (TLS), which can extract an individual tree by using its unique distance information, provides a possibility for indirectly measuring the leaf area index (LAI) in urban areas. However, indirect LAI measurement theory, which uses the cosine of an observation zenith angle for path-length correction, is incompatible for an individual tree because the representative projected area of LAI changes while the observation zenith angle changes, thus making the results incomparable and ambiguous. Therefore, we modified a path length distribution model for the leaf area measurement of an individual tree by replacing the traditional cosine path length correction for a continuous canopy with real path length distribution. We reconstructed the tree crown envelope from a TLS point cloud and calculated a real path length distribution through laser pulse-envelope intersections. Consequently, leaf area density was separated from the path length distribution model for leaf area calculation. Comparisons with reference measurement for an individual tree showed that the TLS-derived leaf area using the path length distribution is insensitive to the scanning resolution and agrees well with an allometric measurement with an overestimation from 5 m2 to 18 m2 (3–10%, respectively). Results from different stations are globally consistent, and using a weighted mean for different stations by sample numbers further improves the universality and efficiency of the proposed method. Further automation of the proposed method can facilitate a rapid and operational leaf area extraction of an individual tree for urban climate modeling. Numéro de notice : A2018-402 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.07.015 Date de publication en ligne : 14/08/2018 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.07.015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90854
in ISPRS Journal of photogrammetry and remote sensing > vol 144 (October 2018) . - pp 357 - 368[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2018101 RAB Revue Centre de documentation En réserve L003 Disponible 081-2018103 DEP-EXM Revue LASTIG Dépôt en unité Exclu du prêt 081-2018102 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt Method for real-time self-calibrating GLONASS code inter-frequency bias and improvements on single point positioning / Liang Chen in GPS solutions, vol 22 n° 4 (October 2018)
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Titre : Method for real-time self-calibrating GLONASS code inter-frequency bias and improvements on single point positioning Type de document : Article/Communication Auteurs : Liang Chen, Auteur ; Min Li, Auteur ; Zhigang Hu, Auteur ; et al., Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] auto-étalonnage
[Termes IGN] données GLONASS
[Termes IGN] données GPS
[Termes IGN] erreur systématique
[Termes IGN] positionnement ponctuel précis
[Termes IGN] temps réelMots-clés libres : code inter-frequency bias (cIFB) Résumé : (Auteur) Utilization of frequency-division multiple access (FDMA) leads to GLONASS pseudorange and carrier phase observations suffering from variable levels inter-frequency bias (IFB). The bias related with carrier phase can be absorbed by ambiguities. However, the unequal code inter-frequency bias (cIFB) will degrade the accuracy of pseudorange observations, which will affect positioning accuracy and convergence of precise point positioning (PPP) when including GLONASS satellites. Based on observations made on un-differenced (UD) ionospheric-free combinations, GLONASS cIFB parameters are estimated as a constant to achieve GLONASS cIFB real-time self-calibration on a single station. A total of 23 stations, with different manufacturing backgrounds, are used to analyze the characteristics of GLONASS cIFB and its relationship with variable receiver hardware. The results show that there is an obvious common trend in cIFBs estimated using broadcast ephemeris for all of the different manufacturers, and there are unequal GLONASS inter-satellite cIFB that match brand manufacture. In addition, a particularly good consistency is found between self-calibrated receiver-dependent GLONASS cIFB and the IFB products of the German Research Centre for Geosciences (GFZ). Via a comparative experiment, it is also found that the algorithm of cIFB real-time self-calibration not only corrects receiver-dependent cIFB, but can moreover eliminate satellite-dependent cIFB, providing more stable results and further improving global navigation satellite system (GNSS) point positioning accuracy. The root mean square (RMS) improvements of single GLONASS standard point positioning (SPP) reach up to 54.18 and 53.80% in horizontal and vertical direction, respectively. The study’s GLONASS cIFB self-estimation can realize good self-consistency between cIFB and stations, working to further promote convergence efficiency relative to GPS + GLONASS PPP. An average improvement percentage of 19.03% is observed, realizing a near-consistent accuracy with GPS + GLONASS fusion PPP. Numéro de notice : A2018-378 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-018-0774-2 Date de publication en ligne : 17/08/2018 En ligne : https://doi.org/10.1007/s10291-018-0774-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90782
in GPS solutions > vol 22 n° 4 (October 2018)[article]A multi‐objective framework for analysis of road network vulnerability for relief facility location during flood hazards : A case study of relief location analysis in Bankura District, India / Omprakash Chakraborty in Transactions in GIS, vol 22 n° 5 (October 2018)
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Titre : A multi‐objective framework for analysis of road network vulnerability for relief facility location during flood hazards : A case study of relief location analysis in Bankura District, India Type de document : Article/Communication Auteurs : Omprakash Chakraborty, Auteur ; Arup Das, Auteur ; Arindam Dasgupta, Auteur ; et al., Auteur Année de publication : 2018 Article en page(s) : pp 1064 - 1082 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] Bengale-Occidental (Inde ; état)
[Termes IGN] gestion des risques
[Termes IGN] inondation
[Termes IGN] réseau routier
[Termes IGN] vulnérabilitéRésumé : (Auteur) The location of disaster management facilities is a challenging and multifaceted problem. The road networks, population distribution along the road networks, and disaster risk maps are the major components for management of this problem. This article aims to decide on the location of such facilities for flood hazards in a region. The methodology is based on a multi‐objective framework. Objective functions include edge importance indices under fair weather and elevation parameters of the edges. Multiple scenarios are simulated for varying levels of hazard, and the outputs are analyzed. Analyses are carried out for the individual percentage loss of road links. A case study has been presented for the Bankura District in West Bengal, India. The inferences drawn from the results identify the critical links over the road networks of the region. The study also indicates locations in the region for relief facility setups to enable best‐serving capabilities and provide safe shelters, even in the most adverse flood conditions. The article depicts the vulnerability status of the road networks of the region. Further, it identifies the locations for relief facility provisioning that bring out the best road utilization and the best‐serving capabilities within the flood‐affected area under different flood levels. Numéro de notice : A2018-569 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12314 Date de publication en ligne : 11/10/2018 En ligne : https://doi.org/10.1111/tgis.12314 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92288
in Transactions in GIS > vol 22 n° 5 (October 2018) . - pp 1064 - 1082[article]Predicting tree diameter distributions from airborne laser scanning, SPOT 5 satellite, and field sample data in the perm region, Russia / Jussi Peuhkurinen in Forests, vol 9 n° 10 (October 2018)
PermalinkTowards a polyalgorithm for land use change detection / Rishu Saxena in ISPRS Journal of photogrammetry and remote sensing, vol 144 (October 2018)
PermalinkAnnual net nitrogen mineralization and litter flux in well-drained downy birch, Norway spruce and Scots pine forest ecosystems / Hardo Becker in Silva fennica, vol 52 n° 4 (September 2018)
PermalinkConfigurable 3D scene synthesis and 2D image rendering with per-pixel ground truth using stochastic grammars / Chenfanfu Jiang in International journal of computer vision, vol 126 n° 9 (September 2018)
PermalinkDrought sensitiveness on forest growth in peninsular Spain and the Balearic Islands / Marina Peña-Gallardo in Forests, vol 9 n° 9 (September 2018)
PermalinkEstimation and uncertainty of the mixing effects on Scots pine—European beech productivity from national forest inventories data / Sonia Condés in Forests, vol 9 n° 9 (September 2018)
PermalinkEstimation of winter wheat crop growth parameters using time series Sentinel-1A SAR data / P. Kumar in Geocarto international, vol 33 n° 9 (September 2018)
PermalinkFine-grained prediction of urban population using mobile phone location data / Jie Chen in International journal of geographical information science IJGIS, vol 32 n° 9-10 (September - October 2018)
PermalinkIn-situ measurements from mobile platforms: An emerging approach to address the old challenges associated with forest inventories / Xinlian Liang in ISPRS Journal of photogrammetry and remote sensing, vol 143 (September 2018)
PermalinkIntegrating multi-agent evacuation simulation and multi-criteria evaluation for spatial allocation of urban emergency shelters / Jia Yu in International journal of geographical information science IJGIS, vol 32 n° 9-10 (September - October 2018)
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