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Spatial association between regionalizations using the information-theoretical V-measure / Jakub Nowosad in International journal of geographical information science IJGIS, vol 32 n° 11-12 (November - December 2018)
[article]
Titre : Spatial association between regionalizations using the information-theoretical V-measure Type de document : Article/Communication Auteurs : Jakub Nowosad, Auteur ; Tomasz F. Stepinski, Auteur Année de publication : 2018 Article en page(s) : pp 2386 - 2401 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse de groupement
[Termes IGN] analyse de variance
[Termes IGN] distribution spatiale
[Termes IGN] logiciel libre
[Termes IGN] régionalisation (segmentation)
[Termes IGN] variableRésumé : (Auteur) There is a keen interest in calculating spatial associations between two variables spanning the same study area. Many methods for calculating such associations have been proposed, but the case when both variables are categorical is underdeveloped despite the fact that many datasets of interest are in the form of either regionalizations or thematic maps. In this paper, we advance this case by adapting the so-called -measure method from its original information-theoretical formulation to the analysis of variance formulation which provides more insight for spatial analysis. We present a step-by-step derivation of the -measure from the perspective of the analysis of variance. The method produces three indices of global association and two sets of local association indicators which could be mapped to indicate spatial distribution of association strength. The open-source software for calculating all indices from vector datasets accompanies the paper. To showcase the utility of the -measure, we identified three different application contexts: comparative, associative, and derivative, and present an example of each of them. The -measure method has several advantages over the widely used Mapcurves method, it has clear interpretations in terms of mutual information as well as in terms of analysis of variance, it provides more precise assessment of association, it is ready-to-use through the accompanying software, and the examples given in the paper serves as a guide to the gamut of its possible applications. Two specific contributions stemming from our re-analysis of the -measure are the finding of the conceptual flaw in the Geographical Detector—a method to quantify associations between numerical and categorical spatial variables, and a proposal for the new, cartographically based algorithm for finding an optimal number of regions in clustering-derived regionalizations. Numéro de notice : A2018-526 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2018.1511794 Date de publication en ligne : 30/08/2018 En ligne : https://doi.org/10.1080/13658816.2018.1511794 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91353
in International journal of geographical information science IJGIS > vol 32 n° 11-12 (November - December 2018) . - pp 2386 - 2401[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2018061 RAB Revue Centre de documentation En réserve L003 Disponible Focal plant species and soil factors in Mediterranean coastal dunes: An undisclosed liaison? / Claudia Angiolini in Estuarine, Coastal and Shelf Science, vol 211 (31 October 2018)
[article]
Titre : Focal plant species and soil factors in Mediterranean coastal dunes: An undisclosed liaison? Type de document : Article/Communication Auteurs : Claudia Angiolini, Auteur ; Gianmaria Bonari, Auteur ; Marco Landi, Auteur Année de publication : 2018 Article en page(s) : pp 248 - 258 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse canonique
[Termes IGN] dune
[Termes IGN] facteur édaphique
[Termes IGN] indicateur biologique
[Termes IGN] littoral méditerranéen
[Termes IGN] microhabitat
[Termes IGN] pédologie locale
[Termes IGN] placette d'échantillonnage
[Termes IGN] Toscane (Italie)
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Understanding the response of plant species to soil factors on coastal sand dunes is critical for effective conservation of coastal habitats in the Mediterranean basin. Our main objectives were to investigate: i) the main soil factors driving species composition in a Mediterranean coastal dune environment; ii) the ecological requirements of focal plant species with respect to single soil factors; iii) whether the focal species of a given macrohabitat (including EU habitats) have similar edaphic needs. We identified 108 plots with three macrohabitats as strata (embryo dunes; mobile dunes; fixed dunes) by random stratified sampling design along the Tyrrhenian coast of central Italy in areas with a high degree of biodiversity and naturalness. Vegetation and soil data were collected in the plots.
Canonical Correspondence Analysis (CCA) confirmed that soil had a main role in driving focal dune species composition as found in other Mediterranean areas and indicated that three factors (field capacity, pH and CaCO3) sufficiently explain patterns of plant species. An inverse relation between field capacity, which proves to be the most decisive feature for differences in species ecological requirements between macrohabitats, and pH was observed. Generalized Additive Models (GAMs) showed that: i) the focal species of fixed dunes have a higher probability of occurrence and response curves that overlap at high field capacity and TOC values and at low pH, showing an opposite trend with respect to the species of embryonic and mixed dunes; ii) species of mixed dunes have a probability of occurrence linked to different values of CaCO3, with Ammophila arenaria showing its optimum at high CaCO3 values. Thus our results sustain the hypothesis that dune focal species, diagnostic and characteristic of coastal dune marcohabitats, have different ecological responses with respect to soil factors. Moreover, species within the same habitat can have different ecological responses due to species competition. Data about edaphic requirements of sand dune species and modelling of their ecological responses suggests that focal dune species can be bio-indicators of soil conditions and provide useful indications for conservation, monitoring and restoration of Mediterranean coastal habitats.Numéro de notice : A2017-249 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.ecss.2017.06.001 Date de publication en ligne : 08/06/2017 En ligne : https://doi.org/10.1016/j.ecss.2017.06.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85209
in Estuarine, Coastal and Shelf Science > vol 211 (31 October 2018) . - pp 248 - 258[article]Scalable individual tree delineation in 3D point clouds / Jinhu Wang in Photogrammetric record, vol 33 n° 163 (September 2018)
[article]
Titre : Scalable individual tree delineation in 3D point clouds Type de document : Article/Communication Auteurs : Jinhu Wang, Auteur ; Roderik Lindenbergh, Auteur ; Massimo Menenti, Auteur Année de publication : 2018 Article en page(s) : pp 315 - 340 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse de groupement
[Termes IGN] arbre (flore)
[Termes IGN] délimitation
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] inventaire de la végétation
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] lasergrammétrie
[Termes IGN] semis de points
[Vedettes matières IGN] Inventaire forestierRésumé : (Auteur) Manually monitoring and documenting trees is labour intensive. Lidar provides a possible solution for automatic tree‐inventory generation. Existing approaches for segmenting trees from original point cloud data lack scalable and efficient methods that separate individual trees sampled by different laser‐scanning systems with sufficient quality under all circumstances. In this study a new algorithm for efficient individual tree delineation from lidar point clouds is presented and validated. The proposed algorithm first resamples the points using cuboid (modified voxel) cells. Consecutively connected cells are accumulated by vertically traversing cell layers. Trees in close proximity are identified, based on a novel cell‐adjacency analysis. The scalable performance of this algorithm is validated on airborne, mobile and terrestrial laser‐scanning point clouds. Validation against ground truth demonstrates an improvement from 89% to 94% relative to a state‐of‐the‐art method while computation time is similar. Numéro de notice : A2018-619 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/phor.12247 Date de publication en ligne : 16/07/2018 En ligne : https://doi.org/10.1111/phor.12247 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92863
in Photogrammetric record > vol 33 n° 163 (September 2018) . - pp 315 - 340[article]Association rules-based multivariate analysis and visualization of spatiotemporal climate data / Feng Wang in ISPRS International journal of geo-information, vol 7 n° 7 (July 2018)
[article]
Titre : Association rules-based multivariate analysis and visualization of spatiotemporal climate data Type de document : Article/Communication Auteurs : Feng Wang, Auteur ; Wenwen Li, Auteur ; Sizhe Wang, Auteur ; Chris R. Johnson, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse géovisuelle
[Termes IGN] analyse multivariée
[Termes IGN] Arctique
[Termes IGN] cyclone
[Termes IGN] données météorologiques
[Termes IGN] données spatiotemporelles
[Termes IGN] phénomène atmosphérique
[Vedettes matières IGN] GéovisualisationRésumé : (Auteur) Understanding atmospheric phenomena involves analysis of large-scale spatiotemporal multivariate data. The complexity and heterogeneity of such data pose a significant challenge in discovering and understanding the association between multiple climate variables. To tackle this challenge, we present an interactive heuristic visualization system that supports climate scientists and the public in their exploration and analysis of atmospheric phenomena of interest. Three techniques are introduced: (1) web-based spatiotemporal climate data visualization; (2) multiview and multivariate scientific data analysis; and (3) data mining-enabled visual analytics. The Arctic System Reanalysis (ASR) data are used to demonstrate and validate the effectiveness and usefulness of our method through a case study of “The Great Arctic Cyclone of 2012”. The results show that different variables have strong associations near the polar cyclone area. This work also provides techniques for identifying multivariate correlation and for better understanding the driving factors of climate phenomena. Numéro de notice : A2018-503 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi7070266 Date de publication en ligne : 09/07/2018 En ligne : https://doi.org/10.3390/ijgi7070266 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90575
in ISPRS International journal of geo-information > vol 7 n° 7 (July 2018)[article]Using interactions and dynamics for mining groups of moving objects from trajectory data / Corrado Loglisci in International journal of geographical information science IJGIS, vol 32 n° 7-8 (July - August 2018)
[article]
Titre : Using interactions and dynamics for mining groups of moving objects from trajectory data Type de document : Article/Communication Auteurs : Corrado Loglisci, Auteur Année de publication : 2018 Article en page(s) : pp 1436 - 1468 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse de groupement
[Termes IGN] analyse spatio-temporelle
[Termes IGN] données spatiotemporelles
[Termes IGN] objet mobile
[Termes IGN] similitude
[Termes IGN] trajectoire (véhicule non spatial)
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) Advances in tracking technology enable the gathering of spatio-temporal data in the form of trajectories, which when analysed can convey useful knowledge. In particular, discovering groups of moving objects is a valuable means for a wide class of problems related to mobility. The task of group mining has been investigated by considering mostly the spatial closeness and similarity of the trajectories, while little attention has been paid to the relationships between the trajectories and time-changing nature of the trajectories. The relationships may provide evidence of interactions between the moving objects. The time-changing nature may provide evidence of dynamics of the movements. Therefore, interactions and dynamics can be sources of information to be considered in order to discover new forms of groups. Motivated by this, we introduce the concept of crews and propose a method to discover crews. A crew gathers moving objects with similar interactions and similar dynamics. The proposed method relies on i) new movement parameters, which explicitly consider interactions and dynamics, and ii) a distance-free clustering algorithm, which groups objects based on the similarity of the movement parameters. We conduct extensive experiments, which include a quantitative evaluation of the quality of the crews and comparison with alternative solutions. Numéro de notice : A2018-280 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658816.2017.1416473 Date de publication en ligne : 21/12/2017 En ligne : https://doi.org/10.1080/13658816.2017.1416473 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90362
in International journal of geographical information science IJGIS > vol 32 n° 7-8 (July - August 2018) . - pp 1436 - 1468[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2018041 RAB Revue Centre de documentation En réserve L003 Disponible Influences of environmental loading corrections on the nonlinear variations and velocity uncertainties for the reprocessed global positioning system height time series of the crustal movement observation network of China / Peng Yuan in Remote sensing, vol 10 n° 6 (June 2018)PermalinkA simple line clustering method for spatial analysis with origin-destination data and its application to bike-sharing movement data / Biao He in ISPRS International journal of geo-information, vol 7 n° 6 (June 2018)PermalinkConnecting infrared spectra with plant traits to identify species / Maria F. Buitrago in ISPRS Journal of photogrammetry and remote sensing, vol 139 (May 2018)PermalinkLong-term prediction of polar motion using a combined SSA and ARMA model / Y. Shen in Journal of geodesy, vol 92 n° 3 (March 2018)PermalinkSensitivity analysis of pansharpening in hyperspectral change detection / Seyd Teymoor Seydi in Applied geomatics, vol 10 n° 1 (March 2018)PermalinkAnalyse de l'incertitude et de la précision thématique de classifications GEOBIA d'une image WorldView-2 / François Messner in Revue Française de Photogrammétrie et de Télédétection, n° 216 (février 2018)PermalinkPredicting temperate forest stand types using only structural profiles from discrete return airborne lidar / Melissa Fedrigo in ISPRS Journal of photogrammetry and remote sensing, vol 136 (February 2018)PermalinkLeveraging correlation across space and time to interpolate geophysical data via CoKriging / Sonja Pravilovic in International journal of geographical information science IJGIS, vol 32 n° 1-2 (January - February 2018)PermalinkUtilisation de QGIS en télédétection, Ch. 2. Apports du MNT topo-bathymétrique pour l'évolution bio-géomorphologique des marais d'Ichkeul (Tunisie) / Zeineb Kassouk (2018)PermalinkBuilding extraction from fused LiDAR and hyperspectral data using Random Forest Algorithm / Saeid Parsian in Geomatica, vol 71 n° 4 (December 2017)Permalink