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A virtual globe-oriented visualization method for 3D meteorological fields / Jing Chen in Geomatics and Information Science of Wuhan University, vol 41 n° 12 (December 2016)
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Titre : A virtual globe-oriented visualization method for 3D meteorological fields Type de document : Article/Communication Auteurs : Jing Chen, Auteur ; Cheng Zou, Auteur ; Wumeng Huang, Auteur ; Boyang Liu, Auteur Année de publication : 2016 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] données localisées 3D
[Termes IGN] données météorologiques
[Termes IGN] globe virtuel
[Termes IGN] requête spatiotemporelle
[Termes IGN] visualisation de données
[Termes IGN] voxel
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) Meteorological fields represent a multidimensional dynamic environment; therefore visualization is a means study inherent regularities in these phenomena. In this paper, aiming to visualize the worldwide, multi-dimensional, multi-scale, massive characteristics of meteorological field data, a voxel object-oriented data model and a voxel based multi-level indexing mechanism were designed. A visualization method for 3D meteorological fields is proposed, including an arrow model based visualization method for vector fields and improved 3D texture-mapping based volume rendering method for scalar fields. Visualization and spatio-temporal retrieval experiments on a Virtual Globe platform were carried out to demonstrate the feasibility and effectiveness of the proposed methods. Numéro de notice : A2016--123 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.13203/j.whugis20140520 En ligne : https://doi.org/10.13203/j.whugis20140520 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84962
in Geomatics and Information Science of Wuhan University > vol 41 n° 12 (December 2016)[article]Evaluation of GPS standard point positioning with various ionospheric error mitigation techniques / Sampad K. Panda in Journal of applied geodesy, vol 10 n° 4 (December 2016)
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Titre : Evaluation of GPS standard point positioning with various ionospheric error mitigation techniques Type de document : Article/Communication Auteurs : Sampad K. Panda, Auteur ; Shirish S. Gedam, Auteur Année de publication : 2016 Article en page(s) : pp 211 – 221 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] correction ionosphérique
[Termes IGN] positionnement par GPS
[Termes IGN] précision du positionnement
[Termes IGN] récepteur bifréquence
[Termes IGN] récepteur monofréquence
[Termes IGN] retard ionosphèrique
[Termes IGN] teneur totale en électronsRésumé : (auteur) The present paper investigates accuracy of single and dual-frequency Global Positioning System (GPS) standard point positioning solutions employing different ionosphere error mitigation techniques. The total electron content (TEC) in the ionosphere is the prominent delay error source in GPS positioning, and its elimination is essential for obtaining a relatively precise positioning solution. The estimated delay error from different ionosphere models and maps, such as Klobuchar model, global ionosphere models, and vertical TEC maps are compared with the locally derived ionosphere error following the ion density and frequency dependence with delay error. Finally, the positional accuracy of the single and dual-frequency GPS point positioning solutions are probed through different ionospheric mitigation methods including exploitation of models, maps, and ionosphere-free linear combinations and removal of higher order ionospheric effects. The results suggest the superiority of global ionosphere maps for single-frequency solution, whereas for the dual-frequency measurement the ionosphere-free linear combination with prior removal of higher-order ionosphere effects from global ionosphere maps and geomagnetic reference fields resulted in improved positioning quality among the chosen mitigation techniques. Conspicuously, the susceptibility of height component to different ionospheric mitigation methods are demonstrated in this study which may assist the users in selecting appropriate technique for precise GPS positioning measurements. Numéro de notice : A2016-972 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2016-0019 En ligne : https://doi.org/10.1515/jag-2016-0019 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83679
in Journal of applied geodesy > vol 10 n° 4 (December 2016) . - pp 211 – 221[article]Exposure-related forest-steppe: A diverse landscape type determined by topography and climate / Martin Hais in Journal of Arid Environments, vol 135 (December 2016)
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Titre : Exposure-related forest-steppe: A diverse landscape type determined by topography and climate Type de document : Article/Communication Auteurs : Martin Hais, Auteur ; Milan Chytrý, Auteur ; Michal Horsak, Auteur Année de publication : 2016 Article en page(s) : pp 75 - 84 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] climat continental
[Termes IGN] hétérogénéité spatiale
[Termes IGN] image Landsat
[Termes IGN] modèle numérique de surface
[Termes IGN] occupation du sol
[Termes IGN] pente
[Termes IGN] précipitation
[Termes IGN] Sibérie
[Termes IGN] steppe
[Termes IGN] topographie locale
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Topographic heterogeneity under dry continental climate can create a landscape mosaic called “exposure-related forest-steppe”, characterized by a regular pattern of forest on the north- and steppe on the south-facing slopes. Here we identify the climatic and topographic determinants of this landscape type, using a model of the Altai Mountains in southern Siberia because they (1) contain large areas of forest-steppe together with forested and steppe landscapes, and (2) possess well-preserved natural land-cover. Based on the Landsat land-cover classification and digital elevation model we identified areas containing exposure-related forest-steppe and modeled their climatic and topographic thresholds using regression trees. The models showed that in the Altai exposure-related forest-steppe is most common in topographically heterogeneous areas with May–September precipitation of 226–377 mm and a mean July temperature of 13.8–15.6 °C. Its existence is jointly determined by hilly topography and a climate that is moist enough to support tree growth on north-facing slopes, but insufficiently so to support woodland development on south-facing slopes. This is consistent with the concept of effective topographic heterogeneity, suggesting that topographic heterogeneity on the landscape level is translated into high habitat diversity and species diversity only within a certain range of climatic conditions. Numéro de notice : A2016--158 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.jaridenv.2016.08.011 Date de publication en ligne : 31/08/2016 En ligne : https://doi.org/10.1016/j.jaridenv.2016.08.011 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86984
in Journal of Arid Environments > vol 135 (December 2016) . - pp 75 - 84[article]Monitoring and prediction of precipitable water vapor using GPS data in Turkey / Kutubuddin Ansari in Journal of applied geodesy, vol 10 n° 4 (December 2016)
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Titre : Monitoring and prediction of precipitable water vapor using GPS data in Turkey Type de document : Article/Communication Auteurs : Kutubuddin Ansari, Auteur ; Omar F. Althuwaynee, Auteur ; Ozsen Corumluoglu, Auteur Année de publication : 2016 Article en page(s) : pp 233 – 245 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] analyse diachronique
[Termes IGN] données météorologiques
[Termes IGN] effet atmosphérique
[Termes IGN] précipitation
[Termes IGN] réfraction atmosphérique
[Termes IGN] réseau géodésique permanent
[Termes IGN] signal GPS
[Termes IGN] température
[Termes IGN] Turquie
[Termes IGN] vapeur d'eauRésumé : (auteur) Although Global Positioning System (GPS) primarily provide accurate estimates of position, velocity and time of the receiver, as the signals pass through the atmoshphere carrying its signatures, thus offers opportunities for atmoshpheric applications. Precipitable water vapor (PWV) is a vital component of the atmosphere and significantly influences atmospheric processes like rainfall and atmospheric temperature. The developing networks of continuously operating GPS can be used to efficiently estimate PWV. The Turkish Permanent GPS Network (TPGN) is employed to monitor PWV information in Turkey. This work primarily aims to derive long-term data of PWV by using atmospheric path delays observed through continuously operating TPGN from November 2014 to October 2015. A least square mathematical approach was then applied to establish the relation of the observed PWV to rainfall and temperature. The modeled PWV was correlated with PWV estimated from GPS data, with an average correlation of 67.10 %–88.60 %. The estimated root mean square error (RMSE) varied from 2.840 to 6.380, with an average of 4.697. Finally, data of TPGN, rainfall, and temperature were obtained for less than 2 months (November 2015 to December 2015) and assessed to validate the mathematical model. This study provides a basis for determining PWV by using rainfall and temperature data. Numéro de notice : A206-973 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jag-2016-0037 En ligne : https://doi.org/10.1515/jag-2016-0037 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83680
in Journal of applied geodesy > vol 10 n° 4 (December 2016) . - pp 233 – 245[article]Self-thinning in four pine species : an evaluation of potential climate impacts / Pau Brunet-Navarro in Annals of Forest Science, vol 73 n° 4 (December 2016)
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Titre : Self-thinning in four pine species : an evaluation of potential climate impacts Type de document : Article/Communication Auteurs : Pau Brunet-Navarro, Auteur ; Frank J. Sterck, Auteur ; Jordi Vayreda, Auteur ; Jordi Martinez-Vilalta, Auteur ; Godefridus M.J. Mohren, Auteur Année de publication : 2016 Article en page(s) : pp 1025 - 1034 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] auto-éclaircie
[Termes IGN] Catalogne (Espagne)
[Termes IGN] changement climatique
[Termes IGN] diamètre des arbres
[Termes IGN] Pinus halepensis
[Termes IGN] Pinus mugo subsp. uncinata
[Termes IGN] Pinus nigra
[Termes IGN] Pinus sylvestris
[Termes IGN] variabilité
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (Auteur) Self-thinning lines are species- and climate-specific, and they should be used when assessing the capacity of different forest stands to increase biomass/carbon storage.
Context : The capacity of forests to store carbon can help to mitigate the effects of atmospheric CO2 rise and climate change. The self-thinning relationship (average size measure ∼ stand density) has been used to identify the potential capacity of biomass storage at a given density and to evaluate the effect of stand management on stored carbon. Here, a study that shows how the self-thinning line varies with species and climate is presented.
Aims : Our main objective is thus testing whether species identity and climate affect the self-thinning line and therefore the potential amount of carbon stored in living biomass.
Methods : The Ecological and Forest Inventory of Catalonia was used to calculate the self-thinning lines of four common coniferous species in Catalonia, NE Iberian Peninsula (Pinus halepensis, Pinus nigra, Pinus sylvestris and Pinus uncinata). Quadratic mean diameter at breast height was chosen as the average size measure. The self-thinning lines were used to predict the potential diameter at a given density and study the effect of environmental variability.
Results : Species-specific self-thinning lines were obtained. The self-thinning exponent was consistent with the predicted values of −3/2 and −4/3 for mass-based scaling for all species except P. sylvestris. Species identity and climatic variability within species affected self-thinning line parameters.
Conclusion : Self-thinning lines are species-specific and are affected by climatic conditions. These relationships can be used to refine predictions of the capacity of different forest stands to increase biomass/carbon storage.Numéro de notice : A2016--013 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1007/s13595-016-0585-y En ligne : http://dx.doi.org/10.1007/s13595-016-0585-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83859
in Annals of Forest Science > vol 73 n° 4 (December 2016) . - pp 1025 - 1034[article]Variations of total electron content over Serbia during the increased solar activity period in 2013 and 2014 / Dragan Blagojevic in Geodetski vestnik, vol 60 n° 4 (December 2016)
PermalinkOpen-grown trees as key habitats for arthropods in temperate woodlands: The diversity, composition, and conservation value of associated communities / Pavel Sebek in Forest ecology and management, vol 380 (15 november 2016)
PermalinkPermalinkA method for automated snow avalanche debris detection through use of synthetic aperture radar (SAR) imaging / Hannah Vickers in Earth and space science, vol 3 n° 11 (November 2016)
PermalinkA new climatology of maximum and minimum temperature (1951–2010) in the Spanish mainland: a comparison between three different interpolation methods / D. Peña-Angulo in International journal of geographical information science IJGIS, vol 30 n° 11-12 (November - December 2016)
PermalinkReview of the state of the art and future prospects of the ground-based GNSS meteorology in Europe / Guergana Guerova in Atmospheric measurement techniques, vol 9 n° 11 (November 2016)
PermalinkThe socio-environmental data explorer (SEDE) : a social media–enhanced decision support system to explore risk perception to hazard events / Eric Shook in Cartography and Geographic Information Science, vol 43 n° 5 (November 2016)
PermalinkDirect measurement of evapotranspiration from a forest using a superconducting gravimeter / Michel Van Camp in Geophysical research letters, vol 43 n° 19 (15 October 2016)
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PermalinkAutomatic segment-level tree species recognition using high resolution aerial winter imagery / Anton Kuzmin in European journal of remote sensing, vol 49 n° 1 (2016)
PermalinkEstimating the rainfall erosivity for management planning in the Eastern Desert, Egypt / Kh. M. Darwish in Geocarto international, Vol 31 n° 9 - 10 (October - November 2016)
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