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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)
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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 Traitement des nuages de points sous PostGIS / Ludovic Delauné in Géomatique expert, n° 113 (novembre - décembre 2016)
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Titre : Traitement des nuages de points sous PostGIS Type de document : Article/Communication Auteurs : Ludovic Delauné, Auteur Année de publication : 2016 Article en page(s) : pp 19 - 20 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] compression de données
[Termes IGN] données lidar
[Termes IGN] format LAS
[Termes IGN] PostGIS
[Termes IGN] semis de points
[Termes IGN] stockage de donnéesRésumé : (Auteur) [Introduction] Les nuages de points issus des survols laser sont une description remarquablement précise de notre environnement, à partir de laquelle il est possible de dériver un nombre important de données. Cette richesse est en partie liée à leur densité : un équipement de type LIDAR relève jusqu'à deux millions de points par seconde. Cela signifie sept milliards par heure, ces points étant caractérisés par des coordonnées d'espace (x, y, z) plus - accessoirement - des informations de couleurs et/ou de réflectance. Tout cela donne des fichiers qui peuvent facilement atteindre plusieurs téra-octets. D'où la question : comment les stocker pour les exploiter efficacement ? [...] Numéro de notice : A2016-960 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83617
in Géomatique expert > n° 113 (novembre - décembre 2016) . - pp 19 - 20[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 265-2016061 RAB Revue Centre de documentation En réserve L003 Disponible IFN-001-P001918 PER Revue Nogent-sur-Vernisson Salle périodiques Exclu du prêt Developing a web-based system for supervised classification of remote sensing images / Ziheng Sun in Geoinformatica, vol 20 n° 4 (October - December 2016)
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Titre : Developing a web-based system for supervised classification of remote sensing images Type de document : Article/Communication Auteurs : Ziheng Sun, Auteur ; H. Fang, Auteur ; Liping Di, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 629 - 649 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] application web
[Termes IGN] classification automatique
[Termes IGN] classification dirigéeRésumé : (Auteur) Web-based image classification systems aim to provide users with an easy access to image classification function. The existing work mainly focuses on web-based unsupervised classification systems. This paper proposes a web-based supervised classification system framework which includes three modules: client, servlet and service. It comprehensively describes how to combine the procedures of supervised classification into the development of a web system. A series of methods are presented to realize the modules respectively. A prototype system of the framework is also implemented and a number of remote sensing (RS) images are tested on it. Experiment results show that the prototype is capable of accomplishing supervised classification of RS images on the Web. If appropriate algorithms and parameter values are used, the results of the web-based solution could be as accurate as the results of traditional desktop-based systems. This paper lays the foundation on both theoretical and practical aspects for the future development of operational web-based supervised classification systems. Numéro de notice : A2016-812 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s10707-016-0252-3 En ligne : http://dx.doi.org/10.1007/s10707-016-0252-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82612
in Geoinformatica > vol 20 n° 4 (October - December 2016) . - pp 629 - 649[article]On the significance of periodic signals in noise analysis of GPS station coordinates time series / Janusz Bogusz in GPS solutions, vol 20 n° 4 (October 2016)
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Titre : On the significance of periodic signals in noise analysis of GPS station coordinates time series Type de document : Article/Communication Auteurs : Janusz Bogusz, Auteur ; Anna Klos, Auteur Année de publication : 2016 Article en page(s) : pp 655 - 664 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] analyse diachronique
[Termes IGN] bruit (théorie du signal)
[Termes IGN] coordonnées cartésiennes géocentriques
[Termes IGN] GIPSY-OASIS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] série temporelle
[Termes IGN] signal GPS
[Termes IGN] station GPS
[Termes IGN] variation saisonnière
[Termes IGN] vitesseRésumé : (Auteur) Each of the GPS-derived time series consists of the deterministic (functional) and stochastic part. We propose that the deterministic part includes all periodicities from 1st to 9th harmonics of residual Chandler, tropical and draconitic periods and compare it with commonly used calculations of the annual and semi-annual tropical curve. Then, we address the issues of whether all residual periodicities, as proposed here, need to be taken into consideration when performing noise analysis. We use the position time series from 180 International GNSS Service stations obtained at the Jet Propulsion Laboratory using the GIPSY-OASIS software in a Precise Point Positioning mode. The longest series has 22.1 years of GPS daily solutions. The spectral indices range from –0.12 to –0.92, while the median values of “global” spectral indices are equal to: –0.41 ± 0.15, –0.38 ± 0.12 and –0.33 ± 0.18 for North, East and Up components, respectively. All non-modelled geophysical processes or non-included artificial effects in time series lead to an underestimation of errors of velocities, but also to changes in the velocity values themselves. The proposed assumption of seasonals subtraction caused the Akaike information criterion values to show a decrease in the median value of 30 %, which in fact means that all the seasonals mentioned here must be taken into account when analyzing noises. Finally, we noticed that there are some of the GPS stations that improved their velocity uncertainty even of 56 %. Numéro de notice : A2016--027 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1007/s10291-015-0478-9 En ligne : http://dx.doi.org/10.1007/s10291-015-0478-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83929
in GPS solutions > vol 20 n° 4 (October 2016) . - pp 655 - 664[article]SPAWNN: A toolkit for SPatial Analysis With Self-Organizing Neural Networks / Julian Hagenauer in Transactions in GIS, vol 20 n° 5 (October 2016)
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Titre : SPAWNN: A toolkit for SPatial Analysis With Self-Organizing Neural Networks Type de document : Article/Communication Auteurs : Julian Hagenauer, Auteur ; Marco Helbich, Auteur Année de publication : 2016 Article en page(s) : pp 755 – 774 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse combinatoire (maths)
[Termes IGN] carte de Kohonen
[Termes IGN] données massives
[Termes IGN] données socio-économiques
[Termes IGN] intelligence artificielle
[Termes IGN] logiciel libre
[Termes IGN] outil logiciel
[Termes IGN] Philadelphie
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) This article introduces the SPAWNN toolkit, an innovative toolkit for spatial analysis with self-organizing neural networks, which is published as free and open-source software (http://www.spawnn.org). It extends existing toolkits in three important ways. First, the SPAWNN toolkit distinguishes between self-organizing neural networks and spatial context models with which the networks can be combined to incorporate spatial dependence and provides implementations for both. This distinction maintains modularity and enables a multitude of useful combinations for analyzing spatial data with self-organizing neural networks. Second, SPAWNN interactively links different self-organizing networks and data visualizations in an intuitive manner to facilitate explorative data analysis. Third, it implements cutting-edge clustering algorithms for identifying clusters in the trained networks. Toolkits such as SPAWNN are particularly needed when researchers and practitioners are confronted with large amounts of complex and high-dimensional data. The computational performance of the implemented algorithms is empirically demonstrated using high-dimensional synthetic data sets, while the practical functionality highlighting the distinctive features of the toolkit is illustrated with a case study using socioeconomic data of the city of Philadelphia, Pennsylvania. Numéro de notice : A2016-998 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12180 En ligne : http://dx.doi.org/10.1111/tgis.12180 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83778
in Transactions in GIS > vol 20 n° 5 (October 2016) . - pp 755 – 774[article]An adaptable equal-area pseudoconic map projection / Daniel "daan" Strebe in Cartography and Geographic Information Science, Vol 43 n° 4 (September 2016)
PermalinkAn improved LOD specification for 3D building models / Filip Biljecki in Computers, Environment and Urban Systems, vol 59 (September 2016)
PermalinkLa cartographie à l'heure du géoweb : retour sur les nouveaux modes de représentation spatiale des données numériques / Boris Mericskay in Cartes & Géomatique, n° 229-230 (septembre 2016 - février 2017)
PermalinkCHP toolkit : case study of LAIe sensitivity to discontinuity of canopy cover in fruit plantations / Karolina D. Fieber in IEEE Transactions on geoscience and remote sensing, vol 54 n° 9 (September 2016)
PermalinkPermalinkESPON FIT: functional indicators for spatial-aware policy-making / Hadrien Commenges in Cartographica, vol 51 n° 3 (Fall 2016)
PermalinkFrom virtual globes to ArcheoGIS : determining the technical and practical feasibilities / Berdien de Roo in Photogrammetric Engineering & Remote Sensing, PERS, vol 82 n° 9 (September 2016)
PermalinkInteractive map to illustrate seat distributions of political party support levels : a web GIS application / Yifei Chen in Cartographica, vol 51 n° 3 (Fall 2016)
PermalinkMethodology and software solutions for multicriteria evaluation of floodplain retention suitability / Rico Vogel in Cartography and Geographic Information Science, Vol 43 n° 4 (September 2016)
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