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Multiband image fusion based on spectral unmixing / Qi Wei in IEEE Transactions on geoscience and remote sensing, vol 54 n° 12 (December 2016)
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Titre : Multiband image fusion based on spectral unmixing Type de document : Article/Communication Auteurs : Qi Wei, Auteur ; José Bioucas-Dias, Auteur ; Nicolas Dobigeon, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 7236 - 7249 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] fusion d'images
[Termes IGN] image à basse résolution
[Termes IGN] image à haute résolution
[Termes IGN] image hyperspectrale
[Termes IGN] image multibande
[Termes IGN] matrice de covarianceRésumé : (Auteur) This paper presents a multiband image fusion algorithm based on unsupervised spectral unmixing for combining a high-spatial-low-spectral-resolution image and a low-spatial-high-spectral-resolution image. The widely used linear observation model (with additive Gaussian noise) is combined with the linear spectral mixture model to form the likelihoods of the observations. The nonnegativity and sum-to-one constraints resulting from the intrinsic physical properties of the abundances are introduced as prior information to regularize this ill-posed problem. The joint fusion and unmixing problem is then formulated as maximizing the joint posterior distribution with respect to the endmember signatures and abundance maps. This optimization problem is attacked with an alternating optimization strategy. The two resulting subproblems are convex and are solved efficiently using the alternating direction method of multipliers. Experiments are conducted for both synthetic and semi-real data. Simulation results show that the proposed unmixing-based fusion scheme improves both the abundance and endmember estimation compared with the state-of-the-art joint fusion and unmixing algorithms. Numéro de notice : A2016-930 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2016.2598784 En ligne : https://doi.org/10.1109/TGRS.2016.2598784 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83344
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 12 (December 2016) . - pp 7236 - 7249[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)
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Titre : Variations of total electron content over Serbia during the increased solar activity period in 2013 and 2014 Type de document : Article/Communication Auteurs : Dragan Blagojevic, Auteur ; Miljana Todorović Drakul, Auteur ; Oleg Odalovic, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 734 - 744 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse diachronique
[Termes IGN] propagation du signal
[Termes IGN] propagation ionosphérique
[Termes IGN] retard ionosphèrique
[Termes IGN] Serbie
[Termes IGN] signal GPS
[Termes IGN] teneur totale en électrons
[Termes IGN] verticaleRésumé : (auteur) To understand general ionosphere properties over Serbia, an analysis of temporal and spatial ionosphere Total Electron Content (TEC) over the region was performed. The present research focuses on daily, seasonal and spatial ionosphere variations, based on TEC series calculated from the GNSS ie. GPS measurements. This analysis provides for characterization of ionosphere nature and fine structure over Serbia, both locally and regionally. For the days with high solar activity changes of TEC values ranges from minimum 4 Total Electron Content Units (TECU), in night hours, up to 55 TECU around the noon. It is shown that that changes are equivalent to the delay of GPS signals approximately 8.8 m in vertical direction during the (maximum) daily conditions and the delay of 0.6 m during the (minimum) night conditions. Also, it is shows that a seasonal TEC differences follows directly Sun activity during the seasons, and maximal differences of TEC values between the seasons reaching values of 45 TECU, again in the years of high Sun’s activities. For spatial changes all gained results indicate that there exist changes in all directions which cannot be recognized as constant bias or a trend. Numéro de notice : A2016-968 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.15292/geodetski-vestnik.2016.04.734-744 En ligne : http://dx.doi.org/10.15292/geodetski-vestnik.2016.04.734-744 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83673
in Geodetski vestnik > vol 60 n° 4 (December 2016) . - pp 734 - 744[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 139-2016041 RAB Revue Centre de documentation En réserve L003 Disponible The driving forces of landscape change in Europe: A systematic review of the evidence / Tobias Plieninger in Land use policy, vol 57 (30 November 2016)
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Titre : The driving forces of landscape change in Europe: A systematic review of the evidence Type de document : Article/Communication Auteurs : Tobias Plieninger, Auteur ; Hélène Draux, Auteur ; Nora Fagerholm, Auteur ; Claudia Bieling, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 204 - 214 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Aménagement
[Termes IGN] agriculture
[Termes IGN] changement d'occupation du sol
[Termes IGN] changement d'utilisation du sol
[Termes IGN] Europe (géographie politique)
[Termes IGN] paysage
[Termes IGN] urbanisationRésumé : (auteur) Over the past decades, landscapes worldwide have experienced changes (e.g., urbanization, agricultural intensification, expansion of renewable energy uses) at magnitudes that put their sustainability at risk. The understanding of the drivers of these landscape changes remains challenging, partly because landscape research is spread across many domains and disciplines. We here provide a systematic synthesis of 144 studies that identify the proximate and underlying drivers of landscape change across Europe. First, we categorize how driving forces have been addressed and find that most studies consider medium-term time scales and local spatial scales. Most studies assessed only one case study area, one spatial scale, and less than four points in time. Second, we analyze geographical coverage of studies and reveal that countries with a non-European Union/European Free Trade Association membership; low Gross Domestic Product; boreal, steppic, and arctic landscapes; as well as forestland systems are underrepresented in the literature. Third, our review shows that land abandonment/extensification is the most prominent (62% of cases) among multiple proximate drivers of landscape change. Fourthly, we find that distinct combinations of mainly political/institutional, cultural, and natural/spatial underlying drivers are determining landscape change, rather than single key drivers. Our systematic review indicates knowledge gaps that can be filled by: (a) expanding the scope of studies to include underrepresented landscapes; (b) clarifying the identification and role of actors in landscape change; (c) deploying more robust tools and methods to quantitatively assess the causalities of landscape change; (d) setting up long-term studies that go beyond mapping land-cover change only; (e) strengthening cross-site and cross-country comparisons of landscape drivers; (f) designing multi-scale studies that consider teleconnections; (g) considering subtle and novel processes of landscape change. Numéro de notice : A2016--165 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.landusepol.2 En ligne : https://doi.org/10.1016/j.landusepol.2016.04.040 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=87132
in Land use policy > vol 57 (30 November 2016) . - pp 204 - 214[article]Effective number of layers: A new measure for quantifying three-dimensional stand structure based on sampling with terrestrial LiDAR / Martin Ehbrecht in Forest ecology and management, vol 380 (15 november 2016)
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Titre : Effective number of layers: A new measure for quantifying three-dimensional stand structure based on sampling with terrestrial LiDAR Type de document : Article/Communication Auteurs : Martin Ehbrecht, Auteur ; Peter Schall, Auteur ; Julia Juchheim, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 212 - 223 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] canopée
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] feuillu
[Termes IGN] strate végétale
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] voxelRésumé : (auteur) The relevance of stand structural heterogeneity for biodiversity conservation is increasingly recognized and efficient tools for its measurement are demanded. Here, we quantified forest structure by calculating the effective number of layers (ENL) for different Hill Numbers (0D, 1D, 2D) as a measure of vertical structure of a subplot. We than use sampling techniques to cover the horizontal structural variability within study plots. ENL describes the vertical structure based on the occupation of 1 m wide vertical layers by tree components relative to the total space occupation of a stand. Space occupation was quantified by a voxel-model obtained from terrestrial laser scanning (TLS) on 150 forest plots in Germany. We used a single scan approach, which requires less field work and post-processing compared to multiple-scans. Single-scan derived mean ENL and its coefficient of variation successfully differentiated forest structures over a wide range of even-aged, uneven-aged and unmanaged broadleaved and coniferous stands. ENL was correlated to the stand summary measures basal area, quadratic mean diameter and stem density as well as stand age. ENL can be used to describe structural heterogeneity and proved to be efficiently assessable by TLS. Numéro de notice : A2016-701 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1016/j.foreco.2016.09.003 En ligne : http://dx.doi.org/10.1016/j.foreco.2016.09.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82064
in Forest ecology and management > vol 380 (15 november 2016) . - pp 212 - 223[article]Open-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)
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Titre : Open-grown trees as key habitats for arthropods in temperate woodlands: The diversity, composition, and conservation value of associated communities Type de document : Article/Communication Auteurs : Pavel Sebek, Auteur ; Stepan Vodka, Auteur ; Petr Bogusch, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 172 - 181 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Araneae
[Termes IGN] arbre (flore)
[Termes IGN] climat tempéré
[Termes IGN] Coleoptera (ordre)
[Termes IGN] Formicidae
[Termes IGN] habitat forestier
[Termes IGN] Hymenoptera (ordre)
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Temperate open woodlands are recognized as biodiversity hotspots. They are characterised by the presence of scattered, open-grown, often old and large trees (hereafter referred to as “solitary trees”). Such trees are considered keystone ecological features for biodiversity. However, the ecological role of solitary trees and their importance for woodland communities are still not fully understood. Communities of arthropods in temperate forests are often structured not only by the horizontal openness of the stand, but also by vertical stratification. Thus there is a need for comparisons among communities associated with solitary trees and different forest strata. In this study, we analysed the diversity, conservation value, and nestedness of four taxonomic groups (beetles (Coleoptera), bees and wasps (aculeate Hymenoptera), ants (Formicidae), and spiders (Araneae)) on (i) solitary trees in open woodlands, and four habitat types in adjacent closed-canopy forests: (ii) edge-canopy, (iii) edge-understorey, (iv) interior-canopy, and (v) interior-understorey.
Across the focal insect groups, solitary trees harboured the greatest number of species, whilst spider communities were also equally rich in forest edge canopies. The conservation value of communities was highest in solitary trees for beetles, and in solitary trees and edge-canopy habitats for bees and wasps. For spiders, the conservation value was similar across all habitat types, but ordination analysis revealed general preferences for solitary trees among threatened species. We also found that communities from the forest interior were mostly only nested subsets of the communities found on solitary trees. Our results show an important and irreplaceable role that open-grown trees have in maintaining temperate woodland biodiversity. Therefore, preservation and maintenance of open-grown trees should be a primary concern in biological conservation.Numéro de notice : A2016-700 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.foreco.2016.08.052 En ligne : http://dx.doi.org/10.1016/j.foreco.2016.08.052 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82063
in Forest ecology and management > vol 380 (15 november 2016) . - pp 172 - 181[article]An approach for estimating time-variable rates from geodetic time series / Olga Didova in Journal of geodesy, vol 90 n° 11 (November 2016)
PermalinkCulture for all / R. Scibetta in GEO: Geoconnexion international, vol 15 n° 10 (November - December 2016)
PermalinkFast three-dimensional empirical mode decomposition of hyperspectral images for class-oriented multitask learning / Zhi He in IEEE Transactions on geoscience and remote sensing, vol 54 n° 11 (November 2016)
PermalinkGuided superpixel method for topographic map processing / Qiguang Miao in IEEE Transactions on geoscience and remote sensing, vol 54 n° 11 (November 2016)
PermalinkHigh-frequency Earth rotation variations deduced from altimetry-based ocean tides / Matthias Madzak in Journal of geodesy, vol 90 n° 11 (November 2016)
PermalinkInterference localization from space: theoretical background / Luca Canzian in Inside GNSS, vol 11 n° 6 (November - December 2016)
PermalinkLocalization of a mobile laser scanner via dimensional reduction / Ville V. Lehtola, in ISPRS Journal of photogrammetry and remote sensing, vol 121 (November 2016)
PermalinkMultiple kernel learning based on discriminative kernel clustering for hyperspectral band selection / Jie Feng in IEEE Transactions on geoscience and remote sensing, vol 54 n° 11 (November 2016)
PermalinkParallel cartographic modeling: a methodology for parallelizing spatial data processing / Eric Shook in International journal of geographical information science IJGIS, vol 30 n° 11-12 (November - December 2016)
PermalinkA phase-altimetric simulator : studying the sensitivity of Earth-reflected GNSS signals to ocean topography / Aaron Maximilian Semmling in IEEE Transactions on geoscience and remote sensing, vol 54 n° 11 (November 2016)
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