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mR-V: Line simplification through mnemonic rasterization / Emmanuel Stefanakis in Geomatica, vol 70 n° 4 (December 2016)
[article]
Titre : mR-V: Line simplification through mnemonic rasterization Type de document : Article/Communication Auteurs : Emmanuel Stefanakis, Auteur Année de publication : 2016 Article en page(s) : pp 269 - 282 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] arc
[Termes IGN] contour
[Termes IGN] discrétisation
[Termes IGN] données matricielles
[Termes IGN] généralisation automatique de données
[Termes IGN] objet géographique linéaire
[Termes IGN] polyligne
[Termes IGN] rastérisation
[Termes IGN] simplification de contour
[Vedettes matières IGN] GénéralisationRésumé : (auteur) Les entités linéaires (p. ex., les routes, les rivières), les pourtours de surfaces (p. ex., les limites municipales, les rives des lacs) ou les trajectoires d’objets en mouvement (p. ex., les humains, les véhicules) sont représentés sur des cartes papier ou numériques avec des géométries de type polyligne. Les processus d’échantillonnage, de discrétisation et de généralisation donnent lieu à des polylignes représentées par un sous-ensemble de sommets de la ligne originale. La version simplifiée d’une entité linéaire peut enfreindre certaines relations spatiales (topologie, direction ou distance) qui s’appliquent entre la ligne originale et certains autres objets dans l’espace, à moins qu’un modèle qui tient compte du contexte de l’espace avoisinant ne soit appliqué. Ce dernier transforme la simplification de la ligne en un processus plutôt complexe et difficile à automatiser. Cet article présente une méthode qui appuie une simplification uniforme de la ligne sans tenir compte du contexte de son espace avoisinant. La méthode applique des tâches bien connues de géotraitement, par exemple la conversion de polylignes en données matricielles et de données matricielles en polylignes, et elle est conforme aux cartes des tuiles matricielles de même qu’aux systèmes mondiaux de quadrillage discrets. Numéro de notice : A2016--132 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.5623/cig2016-401 En ligne : https://doi.org/10.5623/cig2016-401 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85203
in Geomatica > vol 70 n° 4 (December 2016) . - pp 269 - 282[article]Symbolize map distortion with inscribed circles in polygons / Shipeng Sun in International journal of cartography, vol 2 n° 2 (December 2016)
[article]
Titre : Symbolize map distortion with inscribed circles in polygons Type de document : Article/Communication Auteurs : Shipeng Sun, Auteur Année de publication : 2016 Article en page(s) : pp 166 - 185 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie
[Termes IGN] carte en anamorphose
[Termes IGN] cartogramme
[Termes IGN] déformation géométrique
[Termes IGN] polygone
[Termes IGN] projection
[Termes IGN] symbole graphiqueRésumé : (Auteur) For the representation of geographic information, the distortion resulting from map projections and transformations is unwanted but unavoidable. Identical circles systematically arranged on the Earth's ellipsoid have been extensively used to symbolize the map distortion. Despite their effectiveness and popularity, these circles are not explicitly associated with any specific polygons in the map, thus possibly impairing their relevance if the map-readers are interested in particular regions. More importantly, for the map transformation specifically targeting polygons such as the area cartogram, placing the circles completely within the polygons becomes necessary because two neighboring polygons in an area cartogram could have distinctive distortion characteristics. This paper proposes new computer algorithms to enable a map-distortion symbolization approach based on inscribed circles entirely contained in polygons either on a projected 2D plane or on the Earth's ellipsoid. These inscribed circles in polygons (ICIP) are rendered as a series of maximum or equal-sized circles that are spatially exclusive, that is, without overlapping. Compared with the systematically arranged identical circles, the ICIP give cartographers certain flexibility and a new option for the map-distortion symbolization. Two area cartograms and three map projections are provided as examples to illustrate their usage and possible contribution in different mapping scenarios. Numéro de notice : A2016--061 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/23729333.2016.1179863 En ligne : http://dx.doi.org/10.1080/23729333.2016.1179863 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84216
in International journal of cartography > vol 2 n° 2 (December 2016) . - pp 166 - 185[article]Fourier-based multi-scale representation and progressive transmission of cartographic curves on the internet / Pengcheng Liu in Cartography and Geographic Information Science, vol 43 n° 5 (November 2016)
[article]
Titre : Fourier-based multi-scale representation and progressive transmission of cartographic curves on the internet Type de document : Article/Communication Auteurs : Pengcheng Liu, Auteur ; Xingong Li, Auteur ; Weibo Liu, Auteur ; Tinghua Ai, Auteur Année de publication : 2016 Article en page(s) : pp 454 - 468 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] carte topographique
[Termes IGN] contour
[Termes IGN] généralisation cartographique automatisée
[Termes IGN] géomatique web
[Termes IGN] ligne (géométrie)
[Termes IGN] représentation multiple
[Termes IGN] série de Fourier
[Termes IGN] transmission de données
[Vedettes matières IGN] GénéralisationRésumé : (Auteur) Automatic generation of multi-scale representations from the same spatial data source has been the research focus in map generalization for a long time. Based on the Fourier technique, this paper proposes a continuous, multi-scale representation model for progressive transformation of cartographic curves on the Internet. In our method, all the curves, whether closed or open, are depicted as periodical functions which are further expressed as Fourier series. The convergence degrees of the Fourier series are explored for different kinds of curves, and truncating frequencies are derived based on the similarity between the original and reconstructed curves. Using information theory and the Radical Law in cartography, the relationship between map scales and Fourier frequencies is established. Based on the proposed multi-scale model, we also introduce the principles and implementation of a progressive transmission method. Our method is evaluated using the contours from a topographic map. The results show that our model is a valid approach to multi-scale representation of cartographic curves. Numéro de notice : A2016-695 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/15230406.2015.1088799 En ligne : https://doi.org/10.1080/15230406.2015.1088799 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82034
in Cartography and Geographic Information Science > vol 43 n° 5 (November 2016) . - pp 454 - 468[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-2016051 RAB Revue Centre de documentation En réserve L003 Disponible Rendering interior-filled polygonal vector data in a virtual globe / Mengyun Zhou in International journal of geographical information science IJGIS, vol 30 n° 11-12 (November - December 2016)
[article]
Titre : Rendering interior-filled polygonal vector data in a virtual globe Type de document : Article/Communication Auteurs : Mengyun Zhou, Auteur ; Jing Chen, Auteur ; Jianya Gong, Auteur Année de publication : 2016 Article en page(s) : pp 2208 - 2229 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] données vectorielles
[Termes IGN] Global Multi-resolution Terrain Elevation Data 2010
[Termes IGN] globe virtuel
[Termes IGN] modèle numérique de surface
[Termes IGN] modélisation 3D
[Termes IGN] polygone
[Termes IGN] rendu (géovisualisation)
[Termes IGN] temps réel
[Vedettes matières IGN] GéovisualisationRésumé : (Auteur) Polygonal vector data are important for representing countries, lakes, residential settlements, and other polygonal features. The proper representation of polygonal vector data is the basis of efficient rendering and picking and quick access and display of the analysis results based on polygons (e.g., 3D overlaying and surface area measurement in mountainous areas) in a virtual globe. However, polygonal vector data are displayed using texture-based or boundary-based approaches in most existing virtual globes. The texture-based approach cannot easily support interactive operations (e.g., picking) and spatial analysis (e.g., adjacency analysis and spatial measurement). The boundary-based approach treats the holes as independent features; however, it is difficult to recognize which boundaries constitute a polygon. Further research is needed on how to better organize the polygons to support efficient rendering, picking, and analysis in a virtual globe. In this article, we propose two methods to drape interior filled 2D polygons onto a multi-resolution 3D terrain. Both proposed methods combine polygon clipping and polygon triangulation. The difference between the two methods is in the way holes are eliminated. Method 1 recursively subdivides a terrain triangle until the child-triangles contain no holes; every resulting clipped polygon, which is then triangulated, contains no holes. Method 2 directly clips a polygon against a terrain triangle and creates bridge edges to transform the resulting polygons with holes to degenerate polygons that are further triangulated. The experimental results demonstrate that both proposed methods can efficiently process polygons with holes resulting in appropriate numbers of triangles. The processed interior-filled polygons remain close to the terrain surface in a virtual globe. Both proposed methods support real-time rendering of polygonal vector data in a virtual globe. Numéro de notice : A2016-751 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2016.1165819 En ligne : http://dx.doi.org/10.1080/13658816.2016.1165819 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82340
in International journal of geographical information science IJGIS > vol 30 n° 11-12 (November - December 2016) . - pp 2208 - 2229[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2016061 RAB Revue Centre de documentation En réserve L003 Disponible A Topology-inferred graph-based heuristic algorithm for map simplification / QiuLei Guo in Transactions in GIS, vol 20 n° 5 (October 2016)
[article]
Titre : A Topology-inferred graph-based heuristic algorithm for map simplification Type de document : Article/Communication Auteurs : QiuLei Guo, Auteur ; Hassan A. Karimi, Auteur Année de publication : 2016 Article en page(s) : pp 775 – 789 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] algorithme de généralisation
[Termes IGN] carte heuristique
[Termes IGN] graphe
[Termes IGN] méthode heuristique
[Termes IGN] polyligne
[Termes IGN] relation topologique
[Termes IGN] temps réel
[Termes IGN] voisinage (relation topologique)
[Vedettes matières IGN] GénéralisationRésumé : (auteur) In this article, we present a heuristic map simplification algorithm based on a novel topology-inferred graph model. Compared with the existing algorithms, which only focus either on geometry simplification or on topological consistency, our algorithm simplifies the map composed of series of polylines and constraint points while maintaining the topological relationships in the map, maximizing the number of removal points, and minimizing error distance efficiently. Unlike some traditional geometry simplification algorithms, such as Douglas and Peucker's, which add points incrementally, we remove points sequentially based on a priority determined by heuristic functions. In the first stage, we build a graph to model the topology of points in the map from which we determine whether a point is removable or not. As map generalization is needed in different applications with different requirements, we present two heuristic functions to determine the priority of points removal for two different purposes: to save storage space and to reduce computation time. The time complexity of our algorithm is math formula which is efficient enough to be considered for real-time applications. Experiments on real maps were conducted and the results indicate that our algorithm produces high quality results; one heuristic function results in higher removal points saving storage space and the other improves the time performance significantly. Numéro de notice : A2016-999 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12188 En ligne : http://dx.doi.org/10.1111/tgis.12188 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83779
in Transactions in GIS > vol 20 n° 5 (October 2016) . - pp 775 – 789[article]Finding spatial outliers in collective mobility patterns coupled with social ties / Monica Wachowicz in International journal of geographical information science IJGIS, vol 30 n° 9-10 (September - October 2016)PermalinkModeling spatiotemporal topological relationships between moving object trajectories along road networks based on region connection calculus / Linbing Ma in Cartography and Geographic Information Science, Vol 43 n° 4 (September 2016)PermalinkSatellite images analysis for shadow detection and building height estimation / Gregoris Liasis in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)PermalinkA simulated annealing algorithm for zoning in planning using parallel computing / Inès Santé in Computers, Environment and Urban Systems, vol 59 (September 2016)PermalinkAssessment of vertical TEC mapping functions for space-based GNSS observations / Jiahao Zhong in GPS solutions, vol 20 n° 3 (July 2016)PermalinkA point-based methodology for the automatic positional accuracy assessment of geospatial databases / Juan J. Ruiz-Lendínez in Survey review, vol 48 n° 349 (July 2016)PermalinkUsing classification trees to predict forest structure types from LiDAR data / Chiara Torresan in Annals of forest research, vol 59 n° 2 (July - December 2016)PermalinkAn improved ANUDEM method combining topographic correction and DEM interpolation / Xianwei Zheng in Geocarto international, vol 31 n° 5 - 6 (May - June 2016)PermalinkBarycentre method for solving distance equations / X. Shuqiang in Survey review, vol 48 n° 348 (May 2016)PermalinkRobust approximation of the Medial Axis Transform of LiDAR point clouds as a tool for visualisation / Ravi Peters in Computers & geosciences, vol 90 part A (May 2016)Permalink