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L’impact du voisinage géographique des pays dans l’attribution des votes au Concours Eurovision de la Chanson / Jean-François Gleyze in Cybergeo, European journal of geography, n° 2011 ([01/01/2011])
[article]
Titre : L’impact du voisinage géographique des pays dans l’attribution des votes au Concours Eurovision de la Chanson Titre original : Neighbourhood impact on votes awarding in the Eurovision Song Contest Type de document : Article/Communication Auteurs : Jean-François Gleyze , Auteur Année de publication : 2011 Article en page(s) : n° 515 Note générale : bibliographie Langues : Français (fre) Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse de groupement
[Termes IGN] graphe
[Termes IGN] réseau social
[Termes IGN] voisinage (relation topologique)Résumé : (auteur) The Eurovision Song Contest has been held every year since 1956. The originality of this contest lies in the points awarding system. There is no single jury but, on the contrary, each country is asked to award a given number of points to the countries which performed its favourite songs. Beyond the interest of such a system to collectively rank countries, it provides a long story of the swapped points between countries. Such information makes it possible to detect couples of countries {voter, performer} for whom votes are not exclusively guided by song quality. Currently the media covering the event regularly mention a bias in the votes distribution: according to them, this bias would be caused by geographical proximity and would lead to blocs of nearby countries which overwhelmingly vote for each other. In this article, we try to discuss this assumption. This latter requires to answer the following question: “how can we assess the influence of spatial proximity on the social ties formation?”. Besides this issue, several methodological challenges appear. First, we examine the votes of the 1993-2008 period and we identify the social ties of interest, that is the couples of countries {voter, performer} whose votes significantly diverge from the reference situation (i.e. a competition on song quality). Then, we compare the resulting social network with the spatial countries network by a well-suited statistical method to prove that “over-votes” concern nearby countries. Finally, we highlight clusters of countries tending to over-vote for each other and, in that respect, we define clustering criteria which make sense. We show that these blocs strongly structure the abnormally high votes of the 2009 event. This analysis method combines geographical and social networks and can be extended to the study of phenomena concerning relations between spatialised entities. Numéro de notice : A2011-126 Affiliation des auteurs : COGIT (1988-2011) Thématique : GEOMATIQUE Nature : Article DOI : 10.4000/cybergeo.23451 Date de publication en ligne : 10/01/2011 En ligne : https://doi.org/10.4000/cybergeo.23451 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101421
in Cybergeo, European journal of geography > n° 2011 [01/01/2011] . - n° 515[article]Area aggregation in map generalisation by mixed-integer programming / Jan‐Henrik Haunert in International journal of geographical information science IJGIS, vol 24 n°11-12 (december 2010)
[article]
Titre : Area aggregation in map generalisation by mixed-integer programming Type de document : Article/Communication Auteurs : Jan‐Henrik Haunert, Auteur ; A. Wolff, Auteur Année de publication : 2010 Article en page(s) : pp 1871 - 1897 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] agrégation de données
[Termes IGN] analyse combinatoire (maths)
[Termes IGN] base de données ATKIS
[Termes IGN] base de données topographiques
[Termes IGN] distance
[Termes IGN] généralisation cartographique automatisée
[Termes IGN] graphe
[Termes IGN] jeu de données localisées
[Termes IGN] méthode heuristique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] programmation par contraintes
[Termes IGN] rédaction cartographique
[Termes IGN] sémiologie graphique
[Vedettes matières IGN] GénéralisationRésumé : (Auteur) Topographic databases normally contain areas of different land cover classes, commonly defining a planar partition, that is, gaps and overlaps are not allowed. When reducing the scale of such a database, some areas become too small for representation and need to be aggregated. This unintentionally but unavoidably results in changes of classes. In this article we present an optimisation method for the aggregation problem. This method aims to minimise changes of classes and to create compact shapes, subject to hard constraints ensuring aggregates of sufficient size for the target scale. To quantify class changes we apply a semantic distance measure. We give a graph theoretical problem formulation and prove that the problem is NP-hard, meaning that we cannot hope to find an efficient algorithm. Instead, we present a solution by mixed-integer programming that can be used to optimally solve small instances with existing optimisation software. In order to process large datasets, we introduce specialised heuristics that allow certain variables to be eliminated in advance and a problem instance to be decomposed into independent sub-instances. We tested our method for a dataset of the official German topographic database ATKIS with input scale 1:50,000 and output scale 1:250,000. For small instances, we compare results of this approach with optimal solutions that were obtained without heuristics. We compare results for large instances with those of an existing iterative algorithm and an alternative optimisation approach by simulated annealing. These tests allow us to conclude that, with the defined heuristics, our optimisation method yields high-quality results for large datasets in modest time. Numéro de notice : A2010-554 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810903401008 En ligne : https://doi.org/10.1080/13658810903401008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30746
in International journal of geographical information science IJGIS > vol 24 n°11-12 (december 2010) . - pp 1871 - 1897[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010071 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010072 RAB Revue Centre de documentation En réserve L003 Disponible Modeling the scale dependences of topological relations between lines and regions induced by reduction of attributes / S. Du in International journal of geographical information science IJGIS, vol 24 n°11-12 (december 2010)
[article]
Titre : Modeling the scale dependences of topological relations between lines and regions induced by reduction of attributes Type de document : Article/Communication Auteurs : S. Du, Auteur ; Q. Wang, Auteur ; Luo Guo, Auteur Année de publication : 2010 Article en page(s) : pp 1649 - 1686 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] analyse multiéchelle
[Termes IGN] attribut
[Termes IGN] facteur d'échelle
[Termes IGN] généralisation cartographique automatisée
[Termes IGN] graphe
[Termes IGN] objet géographique linéaire
[Termes IGN] objet géographique zonal
[Termes IGN] relation topologiqueRésumé : (Auteur) The scale dependences of topological relations are caused by the changes of spatial objects at different scales, which are induced by the reduction of attributes. Generally, the detailed partitions and multi-scale attributes are stored in spatial databases, while the coarse partitions are not. Consequently, the detailed topological relations can be computed and regarded as known information, while the coarse relations stay unknown. However, many applications (e.g., multi-scale spatial data query) need to deal with the topological relations at multiple scales. In this study new methods are proposed to model and derive the scale dependences of topological relations between lines and multi-scale region partitions. The scale dependences of topological relations are modeled and used to derive the relations between lines and coarse partitions from the relations about the detailed partitions. The derivation can be performed in two steps. At the first step, the topological dependences between a line and two meeting, covered and contained regions are computed and stored into composition tables, respectively. At the second step, a graph is used to represent the neighboring relations among the regions in a detailed partition. The scale dependences and detailed relations are then used to derive topological relations at the coarse level. Our methods can also be extended to handle the scale dependences of relations about disconnected regions, or the combinations of connected and disconnected regions. Because our methods use the scale dependences to derive relations at the coarse level, rather than generating coarse partition and computing the relations with geometric information, they are more efficient to support scale-dependent applications. Numéro de notice : A2010-547 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658811003591672 En ligne : https://doi.org/10.1080/13658811003591672 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30739
in International journal of geographical information science IJGIS > vol 24 n°11-12 (december 2010) . - pp 1649 - 1686[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010071 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010072 RAB Revue Centre de documentation En réserve L003 Disponible Rapid re-convergences to ambiguity-fixed solutions in precise point positioning / J. Geng in Journal of geodesy, vol 84 n° 12 (December 2010)
[article]
Titre : Rapid re-convergences to ambiguity-fixed solutions in precise point positioning Type de document : Article/Communication Auteurs : J. Geng, Auteur ; X. Meng, Auteur ; A. Dodson, Auteur ; et al., Auteur Année de publication : 2010 Article en page(s) : 10 p. ; pp 705 - 714 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] ambiguïté entière
[Termes IGN] convergence
[Termes IGN] correction ionosphérique
[Termes IGN] positionnement par GPS
[Termes IGN] positionnement ponctuel précis
[Termes IGN] propagation ionosphérique
[Termes IGN] résolution d'ambiguïté
[Termes IGN] Suisse
[Termes IGN] temps réelRésumé : (Auteur) Integer ambiguity resolution at a single receiver can be achieved if the fractional-cycle biases are separated from the ambiguity estimates in precise point positioning (PPP). Despite the improved positioning accuracy by such integer resolution, the convergence to an ambiguity-fixed solution normally requires a few tens of minutes. Even worse, these convergences can repeatedly occur on the occasion of loss of tracking locks for many satellites if an open sky-view is not constantly available, consequently totally destroying the practicability of real-time PPP. In this study, in case of such re-convergences, we develop a method in which ionospheric delays are precisely predicted to significantly accelerate the integer ambiguity resolution. The effectiveness of this method consists in two aspects: first, wide-lane ambiguities can be rapidly resolved using the ionosphere-corrected wide-lane measurements, instead of the noisy Melbourne–Wübbena combination measurements; second, narrow-lane ambiguity resolution can be accelerated under the tight constraints derived from the ionosphere-corrected unambiguous wide-lane measurements. In the test at 90 static stations suffering from simulated total loss of tracking locks, 93.3 and 95.0% of re-convergences to wide-lane and narrow-lane ambiguity resolutions can be achieved within five epochs of 1-Hz measurements, respectively, even though the time latency for the predicted ionospheric delays is up to 180 s. In the test at a mobile van moving in a GPS-adverse environment where satellite number significantly decreases and cycle slips frequently occur, only when the predicted ionospheric delays are applied can the rate of ambiguity-fixed epochs be dramatically improved from 7.7 to 93.6% of all epochs. Therefore, this method can potentially relieve the unrealistic requirement of a continuous open sky-view by most PPP applications and improve the practicability of real-time PPP. Numéro de notice : A2010-558 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-010-0404-4 Date de publication en ligne : 14/08/2010 En ligne : https://doi.org/10.1007/s00190-010-0404-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30750
in Journal of geodesy > vol 84 n° 12 (December 2010) . - 10 p. ; pp 705 - 714[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-02010121 SL Revue Centre de documentation Revues en salle Disponible 266-2010121 SL Revue Centre de documentation Revues en salle Disponible FloodwayGIS : An ArcGIS Visualization Environment to Remodel a Floodway / S. Selvanathan in Transactions in GIS, vol 14 n° 5 (October 2010)
[article]
Titre : FloodwayGIS : An ArcGIS Visualization Environment to Remodel a Floodway Type de document : Article/Communication Auteurs : S. Selvanathan, Auteur ; R. Dymond, Auteur Année de publication : 2010 Article en page(s) : pp 671 - 688 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] ArcGIS
[Termes IGN] canal
[Termes IGN] crue
[Termes IGN] inondation
[Termes IGN] logiciel de visualisation
[Termes IGN] risque naturel
[Termes IGN] Triangulated Irregular NetworkRésumé : (Auteur) Floodway modeling has been performed extensively using HECRAS in floodplain studies. The model output is typically exported in GIS format and the floodway boundaries are overlaid on other spatial data to further edit or remodel the floodway to meet FEMA and local development requirements. In this article, a tightly coupled system comprised of a commercial GIS (ArcGIS) and HECRAS is presented. FloodwayGIS provides a comprehensive visual environment to edit, remodel, spatially analyze, and map floodway boundaries. The environment uses the HECRAS executable engine for every remodeling iteration. Four different encroachment editing options are provided within FloodwayGIS, which eliminates the need for a modeler to switch between HECRAS and GIS in the floodway modeling process, and results in savings of modeling time. FloodwayGIS also provides a mapping algorithm based on TIN intersection to produce smooth floodway boundaries that can be mapped in Digital Flood Insurance Rate Maps (DFIRMs) with minor editing. Numéro de notice : A2010-498 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/j.1467-9671.2010.01225.x Date de publication en ligne : 23/11/2010 En ligne : https://doi.org/10.1111/j.1467-9671.2010.01225.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30690
in Transactions in GIS > vol 14 n° 5 (October 2010) . - pp 671 - 688[article]A road network selection process based on data enrichment and structure detection / Guillaume Touya in Transactions in GIS, vol 14 n° 5 (October 2010)PermalinkExtraction automatique des discontinuités planes à partir d'une scannérisation laser 3D en milieu rocheux / Souhail Hajri in Revue Française de Photogrammétrie et de Télédétection, n° 192 (Septembre 2010)PermalinkQualification de modèles numériques de terrain Lidar pour l'étude de l'érosion : application aux badlands de Draix / F. Panissod in Revue Française de Photogrammétrie et de Télédétection, n° 192 (Septembre 2010)PermalinkAnalysis of the spatial relations among point distributions on a discrete space / Yukio Sadahiro in International journal of geographical information science IJGIS, vol 24 n°7-8 (july 2010)PermalinkEffects of topographic variability and Lidar sampling density on several DEM interpolation methods / Q. Guo in Photogrammetric Engineering & Remote Sensing, PERS, vol 76 n° 6 (June 2010)PermalinkEnrichissement automatique de données par analyse spatiale pour la généralisation de réseaux / Guillaume Touya in Revue internationale de géomatique, vol 20 n° 2 (juin - aout 2010)PermalinkAn evaluation of measures for quantifying map information / Lars Harrie in ISPRS Journal of photogrammetry and remote sensing, vol 65 n° 3 (May - June 2010)PermalinkIdentification de morphologies pariétales en grotte à partir d'un lever laser 3D : application aux salles rouges de l'aven d'Orgnac (Ardèche, France) / Stéphane Jaillet in Revue Française de Photogrammétrie et de Télédétection, n° 191 (Mai 2010)PermalinkObtaining high fidelity triangular Regular Network from only DEM points / T. Gökgöz in Cartographic journal (the), vol 47 n° 2 (May 2010)PermalinkReconstruction de façades par des primitives géométriques à partir de données laser terrestres / Hakim Boulaassal in Revue Française de Photogrammétrie et de Télédétection, n° 191 (Mai 2010)Permalink