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A comparison of geometric approaches to assessing spatial similarity for GIR / P. Frontiera in International journal of geographical information science IJGIS, vol 22 n° 3 (march 2008)
[article]
Titre : A comparison of geometric approaches to assessing spatial similarity for GIR Type de document : Article/Communication Auteurs : P. Frontiera, Auteur ; R. Larson, Auteur ; J. Radke, Auteur Année de publication : 2008 Article en page(s) : pp 337 - 360 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes IGN] approximation
[Termes IGN] indexation spatiale
[Termes IGN] pertinence
[Termes IGN] recherche d'information géographique
[Termes IGN] requête spatiale
[Termes IGN] similitudeRésumé : (Auteur) This research compares the geographic information retrieval (GIR) performance of a set of logistic regression models with those of five non-probabilistic methods that compute a spatial similarity score for a query-document pair. All methods are applied to a test collection of queries and documents indexed spatially by two convex conservative geometric approximations: the minimum bounding box (MBB) and the convex hull. In the comparison, the tested logistic regression models outperform, in terms of standard information retrieval recall and precision measures, all of the non-probabilistic methods. The retrieval performance achieved by the logistic regression models on MBB approximations is similar to that achieved by the use of the non-probabilistic methods on convex hulls. Although these results are valid only for the test collection used in this study, they suggest that a logistic regression approach to GIR provides an alternative to the use of higher-quality geometric representations that are more difficult to obtain, implement, and process. Additionally, this research demonstrates the ability of a probabilistic approach to effectively incorporate information about geographic context in the spatial ranking process. Copyright Taylor & Francis Numéro de notice : A2008-143 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701626293 En ligne : https://doi.org/10.1080/13658810701626293 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29138
in International journal of geographical information science IJGIS > vol 22 n° 3 (march 2008) . - pp 337 - 360[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-08021 RAB Revue Centre de documentation En réserve L003 Disponible 079-08022 RAB Revue Centre de documentation En réserve L003 Disponible Location approximation for local search services using natural language hints / S. Schockaert in International journal of geographical information science IJGIS, vol 22 n° 3 (march 2008)
[article]
Titre : Location approximation for local search services using natural language hints Type de document : Article/Communication Auteurs : S. Schockaert, Auteur ; M. De Cock, Auteur ; E. Kerre, Auteur Année de publication : 2008 Article en page(s) : pp 315 - 336 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes IGN] approximation
[Termes IGN] géomatique web
[Termes IGN] langage naturel (informatique)
[Termes IGN] point d'intérêt
[Termes IGN] recherche d'information géographique
[Termes IGN] service fondé sur la position
[Termes IGN] sous ensemble flou
[Termes IGN] voisinage (relation topologique)Résumé : (Auteur) Local search services allow a user to search for businesses that satisfy a given geographical constraint. In contrast to traditional web search engines, current local search services rely heavily on static, structured data. Although this yields very accurate systems, it also implies a limited coverage, and limited support for using landmarks and neighborhood names in queries. To overcome these limitations, we propose to augment the structured information available to a local search service, based on the vast amount of unstructured and semi-structured data available on the web. This requires a computational framework to represent vague natural language information about the nearness of places, as well as the spatial extent of vague neighborhoods. In this paper, we propose such a framework based on fuzzy set theory, and show how natural language information can be translated into this framework. We provide experimental results that show the effectiveness of the proposed techniques, and demonstrate that local search based on natural language hints about the location of places with an unknown address, is feasible. Copyright Taylor & Francis Numéro de notice : A2008-142 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701626277 En ligne : https://doi.org/10.1080/13658810701626277 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29137
in International journal of geographical information science IJGIS > vol 22 n° 3 (march 2008) . - pp 315 - 336[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-08021 RAB Revue Centre de documentation En réserve L003 Disponible 079-08022 RAB Revue Centre de documentation En réserve L003 Disponible Terrestrial laser scanner to detect landslide displacement fields: a new approach / Giordano Teza in International Journal of Remote Sensing IJRS, vol 28 n°15-16 (August 2007)
[article]
Titre : Terrestrial laser scanner to detect landslide displacement fields: a new approach Type de document : Article/Communication Auteurs : Giordano Teza, Auteur ; A. Galgaro, Auteur ; et al., Auteur Année de publication : 2007 Article en page(s) : pp 3425 - 3446 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Alpes
[Termes IGN] approximation
[Termes IGN] données laser
[Termes IGN] données localisées
[Termes IGN] données multitemporelles
[Termes IGN] effondrement de terrain
[Termes IGN] Italie
[Termes IGN] itération
[Termes IGN] télémétrie laser terrestreRésumé : (Auteur) A terrestrial laser scanner (TLS) allows the generation of a detailed model of a landslide surface. In this way, when two or more georeferenced models obtained by multi-temporal scans are available, the landslide displacement field can be computed. Nevertheless, such a computation is a relatively complex task because the recognition of correspondences among the multi-temporal models is required. The Iterative Closest Point (ICP) algorithm allows the alignment of two 3D objects having a common part by iterative shape matching. A new method for the automatic calculation of a landslide displacement field is presented here. It is based on a piecewise application of the ICP algorithm and is made possible by the robustness of this algorithm against noise and small morphological modifications. After a series of numerical experimentations, this method was successfully applied to two test sites located in the North-Eastern Italian Alps affected by high-risk landslides of the slump type (Perarolo di Cadore and Lamosano) with very different observational conditions. Copyright Taylor & Francis Numéro de notice : A2007-358 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160601024234 En ligne : https://doi.org/10.1080/01431160601024234 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28721
in International Journal of Remote Sensing IJRS > vol 28 n°15-16 (August 2007) . - pp 3425 - 3446[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-07091 RAB Revue Centre de documentation En réserve L003 Disponible Efficient detection of patterns in 2D trajectories of moving points / J. Gudmundsson in Geoinformatica, vol 11 n° 2 (June - August 2007)
[article]
Titre : Efficient detection of patterns in 2D trajectories of moving points Type de document : Article/Communication Auteurs : J. Gudmundsson, Auteur ; Marc Van Kreveld, Auteur ; B. Speckmann, Auteur Année de publication : 2007 Article en page(s) : pp 195 - 215 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] approximation
[Termes IGN] base de données d'objets mobiles
[Termes IGN] exploration de données géographiques
[Termes IGN] géomètrie algorithmique
[Termes IGN] objet mobileRésumé : (Auteur) Moving point object data can be analyzed through the discovery of patterns in trajectories. We consider the computational efficiency of detecting four such spatio-temporal patterns, namely flock, leadership, convergence, and encounter, as defined by Laube et al., Finding REMO—detecting relative motion patterns in geospatial lifelines, 201–214, (2004). These patterns are large enough subgroups of the moving point objects that exhibit similar movement in the sense of direction, heading for the same location, and/or proximity. By the use of techniques from computational geometry, including approximation algorithms, we improve the running time bounds of existing algorithms to detect these patterns. Copyright Springer Numéro de notice : A2007-237 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-006-0002-z En ligne : https://doi.org/10.1007/s10707-006-0002-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28600
in Geoinformatica > vol 11 n° 2 (June - August 2007) . - pp 195 - 215[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 057-07021 RAB Revue Centre de documentation En réserve L003 Disponible Accuracy of quantized Voronoi diagrams / Yukio Sadahiro in International journal of geographical information science IJGIS, vol 20 n° 10 (november 2006)
[article]
Titre : Accuracy of quantized Voronoi diagrams Type de document : Article/Communication Auteurs : Yukio Sadahiro, Auteur ; T. Tominaga, Auteur Année de publication : 2006 Article en page(s) : pp 1173 - 1189 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] approximation
[Termes IGN] diagramme de Voronoï
[Termes IGN] maille triangulaire
[Termes IGN] objet géographique
[Termes IGN] tessellationRésumé : (Auteur) Quantization of spatial objects, which usually means vector-to-raster conversion in GIS and remote sensing, is a basic operation used for handling spatial data from data creation to visualization. Since quantization is an approximation of spatial objects, it inevitably yields errors in measuring their properties such as area, perimeter, diameter, and so forth. This paper discusses the accuracy of a quantized Voronoi diagram, a spatial tessellation generated from a set of points. A measure is proposed to evaluate the accuracy of the area of Voronoi regions calculated after quantization. In one-dimensional space the measure is expressed as an explicit function of the expected number of generators in a cell. In two-dimensional space, on the other hand, the measure is defined by an implicit function, whose approximation is derived in an explicit form. These functions permit us to evaluate the accuracy of quantization in relation to the size of lattice cells and the density of Voronoi generators. This leads to an appropriate choice of a lattice to keep the quality of a quantized Voronoi diagram at a desirable level. Copyright Taylor & Francis Numéro de notice : A2006-455 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Article DOI : 10.1080/13658810600816748 En ligne : https://doi.org/10.1080/13658810600816748 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28179
in International journal of geographical information science IJGIS > vol 20 n° 10 (november 2006) . - pp 1173 - 1189[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-06101 RAB Revue Centre de documentation En réserve L003 Disponible 079-06102 RAB Revue Centre de documentation En réserve L003 Disponible Sélection adaptative des dimensions de l'indexation visuelle d'images mal annotées en fonction du mot recherché / S. Tollari in Ingénierie des systèmes d'information, ISI : Revue des sciences et technologies de l'information, RSTI, vol 11 n° 4 (juillet - août 2006)PermalinkMatching topographic surfaces : application to lidar and photogrammetric surfaces / Frédéric Bretar in Revue Française de Photogrammétrie et de Télédétection, n° 182 (Juin 2006)PermalinkAn evolutionary algorithm for multicriteria path optimization problems / P. Mooney in International journal of geographical information science IJGIS, vol 20 n° 4 (april 2006)PermalinkEvaluation of a rough soil surface description with ASAR-ENVISAT radar data / Mehrez Zribi in Remote sensing of environment, vol 95 n° 1 (15/03/2005)PermalinkAnalyse et analyse numérique / Luc Jolivet (2005)PermalinkApproximation de surfaces moléculaires / B. Cotasson (2004)PermalinkPolyline spatial join evaluation using raster approximation / L.G. Azevedo in Geoinformatica, vol 7 n° 4 (December 2003)PermalinkRough and fuzzy geographical data integration / K. Oukbir in International journal of geographical information science IJGIS, vol 17 n° 3 (may 2003)PermalinkGrandes déviations pour des sommes pondérées de variables aléatoires i.i.d. appliquées à un problème géographique / Olivier Bonin in Comptes rendus de l'Académie des Sciences. Série 1, Mathématique, Tome 333 n° 4 (15 août 2001)PermalinkDecomposition of laser altimeter waveforms / M.A. Hofton in IEEE Transactions on geoscience and remote sensing, vol 38 n° 4 Tome 2 (july 2000)Permalink