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Automatic segment-level tree species recognition using high resolution aerial winter imagery / Anton Kuzmin in European journal of remote sensing, vol 49 n° 1 (2016)
[article]
Titre : Automatic segment-level tree species recognition using high resolution aerial winter imagery Type de document : Article/Communication Auteurs : Anton Kuzmin, Auteur ; Lauri Korhonen, Auteur ; Terhikki Manninen, Auteur ; Matti Maltamo, Auteur Année de publication : 2016 Article en page(s) : pp 239 - 259 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse d'image orientée objet
[Termes IGN] analyse discriminante
[Termes IGN] betula pubescens
[Termes IGN] composition floristique
[Termes IGN] forêt boréale
[Termes IGN] hélicoptère
[Termes IGN] hiver
[Termes IGN] image à ultra haute résolution
[Termes IGN] image aérienne
[Termes IGN] neige
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestrisRésumé : (auteur) Our objective was to automatically recognize the species composition of a boreal forest from high-resolution airborne winter imagery. The forest floor was covered by snow so that the contrast between the crowns and the background was maximized. The images were taken from a helicopter flying at low altitude so that fine details of the canopy structure could be distinguished. Segments created by an object-oriented image processing were used as a basis for a linear discriminant analysis, which aimed at separating the three dominant tree species occurring in the area: Scots pine, Norway spruce, and downy birch. In a cross validation, the classification showed an overall accuracy of 81.9%, and a kappa coefficient of 0.73. Numéro de notice : A2016-831 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.5721/EuJRS20164914 En ligne : http://dx.doi.org/10.5721/EuJRS20164914 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82714
in European journal of remote sensing > vol 49 n° 1 (2016) . - pp 239 - 259[article]Diagnostic study of a high‐precipitation event in the Western Mediterranean: adequacy of current operational networks / Samiro Khodayar in Quarterly Journal of the Royal Meteorological Society, vol 142 n° S1 (August 2016)
[article]
Titre : Diagnostic study of a high‐precipitation event in the Western Mediterranean: adequacy of current operational networks Type de document : Article/Communication Auteurs : Samiro Khodayar, Auteur ; F. Raff, Auteur ; Norbert Kalthoff, Auteur ; Olivier Bock , Auteur Année de publication : 2016 Article en page(s) : pp 72 - 85 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] climat méditerranéen
[Termes IGN] données météorologiques
[Termes IGN] inondation
[Termes IGN] littoral méditerranéen
[Termes IGN] modèle de simulation
[Termes IGN] positionnement par GPS
[Termes IGN] précipitation
[Termes IGN] teneur en vapeur d'eauRésumé : (auteur) To investigate whether the spatial and temporal resolution of current operational observing systems in the Western Mediterranean (WMed) region suffice to adequately represent the atmospheric processes responsible for the initiation and intensification of convection, a diagnostic study of the HyMex Intensive Observation Period 8 (IOP8) is performed. During the IOP8, heavy rainfall with intense lightning and consequent devastating flash floods occurred in the WMed region. The synergy of operational networks in the northern WMed, including Global Positioning System (GPS) stations, rain gauges, weather stations, lightning sensors and radiosondes, was used to document in detail the evolution of the heavy precipitation event. In general, the resolution of the aforementioned networks adequately sampled the temporal and spatial variability of the atmospheric water vapour, as well as the position of mesoscale convergence zones which played a key role in the initiation and evolution of convective systems in this case. Nevertheless, high uncertainty was associated with the existence and location of moisture convergence zones and wind convergence lines over the sea, reflecting the need for model analysis and remote‐sensing observations to complete the documentation of the event. Numéro de notice : A2016--195 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/qj.2600 Date de publication en ligne : 11/06/2015 En ligne : https://doi.org/10.1002/qj.2600 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91857
in Quarterly Journal of the Royal Meteorological Society > vol 142 n° S1 (August 2016) . - pp 72 - 85[article]A seamless weather–climate multi‐model intercomparison on the representation of a high impact weather event in the western Mediterranean: HyMeX IOP12 / Samiro Khodayar in Quarterly Journal of the Royal Meteorological Society, vol 142 n° S1 (August 2016)
[article]
Titre : A seamless weather–climate multi‐model intercomparison on the representation of a high impact weather event in the western Mediterranean: HyMeX IOP12 Type de document : Article/Communication Auteurs : Samiro Khodayar, Auteur ; G. Fosser, Auteur ; S. Berthou, Auteur ; Silvio Davolio, Auteur ; Philippe Drobinski, Auteur ; Véronique Ducrocq, Auteur ; Rossella Ferretti, Auteur ; Mathieu Nuret, Auteur ; E. Pichelli, Auteur ; Evelyne Richard, Auteur ; Olivier Bock , Auteur Année de publication : 2016 Projets : HyMeX / Richard, Evelyne Article en page(s) : pp 433 - 452 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] bassin méditerranéen
[Termes IGN] climat méditerranéen
[Termes IGN] convection
[Termes IGN] distribution spatiale
[Termes IGN] données météorologiques
[Termes IGN] humidité de l'air
[Termes IGN] modèle météorologique
[Termes IGN] précipitation
[Termes IGN] vapeur d'eau
[Termes IGN] variabilitéRésumé : (auteur) High Impact Weather (HIW), particularly Heavy Precipitation Events (HPE), are common phenomena affecting the western Mediterranean (WMED) especially in the autumn period. Understanding and evaluating the capability to adequately represent such events in model simulations is one of the main goals of the Hydrological cycle in the Mediterranean Experiment (HyMeX) and the main motivation of this investigation.
In order to gain a better knowledge of the model representation of HPE and related processes we perform a seamless multi‐model intercomparison at the event scale. Limited‐area model runs (grid spacing from 2 to 20 km) at weather and climate time‐scales are considered, four with parametrized and five with explicit convection. The performance of the nine models is compared by analysing precipitation, as well as convection‐relevant parameters. An Intensive Observation Period (IOP12) from the HyMeX‐SOP1 (Special Observation Period) is used to illustrate the results. During IOP12, HPE affected the northwestern Mediterranean region, from Spain to Italy, as a consequence of Mesoscale Convective Systems (MCSs) which initiated and intensified in the area of investigation. Results show that: (i) the timing of the maximum precipitation seems to be linked to the representation of large‐scale conditions rather than differences among models; (ii) Convection Permitting Models (CPMs) exhibit differences among each other, but better represent the short‐intense convective events. All four convection‐parametrized models produce a large number of weak and long‐lasting events. Regional Climate Models (RCMs) capture the occurrence of the event but produce notably lower precipitation amounts and hourly intensities than CPMs and Numerical Weather Prediction (NWP) models with parametrized convection; (iii) these differences do not seem to come from mean moisture or Convective Available Potential Energy (CAPE) which are in the same range for all models, but rather from differences in the variability and vertical distribution of moisture and the triggering of deep convection.Numéro de notice : A2016--174 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/qj.2700 Date de publication en ligne : 29/10/2015 En ligne : https://doi.org/10.1002/qj.2700 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91787
in Quarterly Journal of the Royal Meteorological Society > vol 142 n° S1 (August 2016) . - pp 433 - 452[article]Direction-of-arrival estimation of VHF signals recorded on the international space station and simultaneous observations of optical lightning / Hiroshi Kikuchi in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)
[article]
Titre : Direction-of-arrival estimation of VHF signals recorded on the international space station and simultaneous observations of optical lightning Type de document : Article/Communication Auteurs : Hiroshi Kikuchi, Auteur ; Takeshi Morimoto, Auteur ; Mitsuteru Sato, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 3868 - 3877 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] interférométrie
[Termes IGN] onde métrique
[Termes IGN] orage
[Termes IGN] positionnement absolu
[Termes IGN] propagation ionosphérique
[Termes IGN] radiomètre à hyperfréquence
[Termes IGN] rayonnement électromagnétiqueRésumé : (Auteur) We report an initial investigation of the new location method of a very high frequency (VHF) radiation source, using signals recorded at the International Space Station. A VHF interferometer (VITF) has two VHF sensors. Locating lightning with VHF bands is useful to locate the position of the charge distribution in the thunderstorm. The location method of a radio source proposed used two direction-of-arrival estimation techniques. One is the interferometric technique, and another is based on the ionospheric propagation delay measurement of received signals. The combination of the two techniques provides two angular positions of the radiation source. When an altitude of a radiation source is assumed, we can determine two possible positions. One of the two positions was associated with the radiation source, while the other was not. In this paper, we compared the position of lightning and sprite imager (LSI) data, which are simultaneously captured during a lightning emission, with the locating position near the emission. The data set of the VITF within 100 ms of the optical lightning emission captured with the LSI was used. The temporally simultaneous event seems to be associated with the same lightning event. The estimated radiation positions were spatially in close agreement with the optical lightning positions captured with LSI, under nighttime ionosphere conditions. From statistical analysis, the spatial difference of the standard deviation changed from 15.3 to 30.8 km depending on the installation direction of the VHF sensors. The usefulness and limitations of the method are also discussed. Numéro de notice : A2016-874 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2016.2529658 En ligne : http://dx.doi.org/10.1109/TGRS.2016.2529658 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83033
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 7 (July 2016) . - pp 3868 - 3877[article]Wavelet analysis of low-frequency variability in oak tree-ring chronologies from east Central Europe / Asok K. Sen in Open geosciences, vol 8 n° 1 (January - July 2016)
[article]
Titre : Wavelet analysis of low-frequency variability in oak tree-ring chronologies from east Central Europe Type de document : Article/Communication Auteurs : Asok K. Sen, Auteur ; Zoltan Kern, Auteur Année de publication : 2016 Article en page(s) : pp 478 - 483 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] analyse diachronique
[Termes IGN] dendrochronologie
[Termes IGN] Europe centrale
[Termes IGN] ondelette
[Termes IGN] précipitation
[Termes IGN] Quercus (genre)
[Termes IGN] série temporelle
[Termes IGN] variabilitéRésumé : (auteur) This study investigates the low-frequency (interannual and longer period) variability in three hydroclimatic records from east Central Europe. Two of these records consist of climate proxies derived from oak-tree rings in Bakta forest, and Balaton Highlands in Hungary, for the time interval 1783-2003. The third record consists of homogenized instrumental precipitation data from Budapest, Hungary, from 1842 to 2003. Using wavelet analysis, the three time series are analyzed and compared with one another. It is found that all three time series exhibit strong interannual variability at the 2-4 years timescales, and these variations occur intermittently throughout the length of each record. Significant variability is also observed in all the records at decadal timescales, but these variations persist for only two to three cycles. Wavelet coherence among the various time series is used to explore their time-varying correlation. The results reveal significant coherence at the 2-4 years band. At these timescales, the climatic variations are correlated to the tree-ring signal over different time intervals with changing phase. Increased (decreased) contribution of large-scale stratiform precipitation offers a potential explanation for enhanced (faded) coherence at the interannual timescale. Strong coherence was also observed occasionally at decadal timescales, however these coherences did not appear uniformly. These results reinforce the earlier assertion that neither the strength nor the rank of the similarity of the local hydroclimate signals is stable throughout the past two centuries. Numéro de notice : A2016--070 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1515/geo-2016-0044 En ligne : https://doi.org/10.1515/geo-2016-0044 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84416
in Open geosciences > vol 8 n° 1 (January - July 2016) . - pp 478 - 483[article]L'essor soudain du "vivre avec" le risque / Pierre Clergeot in Géomètre, n° 2136 (mai 2016)PermalinkStorm 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)PermalinkExtreme events and climate change: the post-disaster dynamics of forest fires and forest storms in Sweden / Rolf Lidskog in Scandinavian journal of forest research, vol 31 n° 2 (March 2016)PermalinkUn modèle global d'anticipation des mouvements de terrain / Anonyme in GEOrama, le journal d'Information du BRGM, n° 32 (mars 2016)PermalinkA comprehensive cartographic approach to evacuation map creation for Hurricane Ike in Galveston County, Texas / Yin-Hsuen Chen in Cartography and Geographic Information Science, Vol 43 n° 1 (January 2016)PermalinkThe ill wind that blew some good / Miroslav Holubec in GEO: Geoconnexion international, vol 15 n° 1 (January 2016)PermalinkPermalinkSlopeManagement via satellite navigation / Daniel Maurice in Geoinformatics, vol 18 n° 8 (December 2015)PermalinkCiel sous contrôle : enquête SIG et climat / Steve Carpentier in SIGmag, n° 6 (octobre 2015)PermalinkEstimation of precipitation fields from 1-minute rain gauge time series – comparison of spatial and spatio-temporal interpolation methods / D. Fitzner in International journal of geographical information science IJGIS, vol 29 n° 9 (September 2015)Permalink