Descripteur
Documents disponibles dans cette catégorie (638)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
A marked point process for modeling lidar waveforms / Clément Mallet in IEEE Transactions on image processing, vol 19 n° 12 (December 2010)
[article]
Titre : A marked point process for modeling lidar waveforms Type de document : Article/Communication Auteurs : Clément Mallet , Auteur ; Florent Lafarge, Auteur ; Michel Roux, Auteur ; Uwe Soergel, Auteur ; Frédéric Bretar, Auteur ; Christian Heipke, Auteur Année de publication : 2010 Projets : 1-Pas de projet / Article en page(s) : pp 3204 - 3221 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] algorithme du recuit simulé
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] méthode de Monte-Carlo par chaînes de Markov
[Termes IGN] signal laserRésumé : (auteur) Lidar waveforms are 1-D signals representing a train of echoes caused by reflections at different targets. Modeling these echoes with the appropriate parametric function is useful to retrieve information about the physical characteristics of the targets. This paper presents a new probabilistic model based upon a marked point process which reconstructs the echoes from recorded discrete waveforms as a sequence of parametric curves. Such an approach allows to fit each mode of a waveform with the most suitable function and to deal with both, symmetric and asymmetric, echoes. The model takes into account a data term, which measures the coherence between the models and the waveforms, and a regularization term, which introduces prior knowledge on the reconstructed signal. The exploration of the associated configuration space is performed by a reversible jump Markov chain Monte Carlo (RJMCMC) sampler coupled with simulated annealing. Experiments with different kinds of lidar signals, especially from urban scenes, show the high potential of the proposed approach. To further demonstrate the advantages of the suggested method, actual laser scans are classified and the results are reported. Numéro de notice : A2010-644 Affiliation des auteurs : MATIS+Ext (1993-2011) Autre URL associée : vers HAL Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TIP.2010.2052825 Date de publication en ligne : 23/07/2010 En ligne : https://doi.org/10.1109/TIP.2010.2052825 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90739
in IEEE Transactions on image processing > vol 19 n° 12 (December 2010) . - pp 3204 - 3221[article]Analysing spatio-temporal autocorrelation with LISTA-Viz / F. Hardisty in International journal of geographical information science IJGIS, vol 24 n° 10 (october 2010)
[article]
Titre : Analysing spatio-temporal autocorrelation with LISTA-Viz Type de document : Article/Communication Auteurs : F. Hardisty, Auteur ; Alexander Klippel, Auteur Année de publication : 2010 Article en page(s) : pp 1515 - 1526 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatio-temporelle
[Termes IGN] autocorrélation
[Termes IGN] corrélation
[Termes IGN] données spatiotemporelles
[Termes IGN] méthode de Monte-CarloRésumé : (Auteur) Many interesting analysis problems (e.g. disease surveillance) would become more tractable if their spatio-temporal structure was better understood. Specifically, it would be helpful to be able to identify autocorrelation in space and time simultaneously. Some of the most commonly used measures of spatial association are LISA statistics, such as the Local Moran's I or the Getis-Ord Gi*; however, these have not been applied to the spatio-temporal case (including many time steps) because of computational limitations. We have implemented a spatio-temporal version of the Local Moran's I and claimed two advances: first, we exploit the fact that there are a limited number of topological relationships present in the data to make Monte Carlo's estimation of probability densities computationally practical, and thereby bypass the 'curse of dimensionality'. We term this approach 'spatial memoization'. Second, we developed a tool (LISTA-Viz) for interacting with the spatio-temporal structure uncovered by the statistics that contains a novel coordination strategy. The potential usefulness of the method and the associated tool are illustrated by an analysis of the 2009 H1N1 pandemic, with the finding that there was a critical spatio-temporal 'inflection point' at which the pandemic changed its character in the United States. Numéro de notice : A2010-464 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658816.2010.511717 En ligne : https://doi.org/10.1080/13658816.2010.511717 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30657
in International journal of geographical information science IJGIS > vol 24 n° 10 (october 2010) . - pp 1515 - 1526[article]Réservation
Réserver ce documentExemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2010061 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010062 RAB Revue Centre de documentation En réserve L003 Disponible Space-time density of trajectories : exploring spatio-temporal patterns in movement data / Urška Demšar in International journal of geographical information science IJGIS, vol 24 n° 10 (october 2010)
[article]
Titre : Space-time density of trajectories : exploring spatio-temporal patterns in movement data Type de document : Article/Communication Auteurs : Urška Demšar, Auteur ; K. Virrantaus, Auteur Année de publication : 2010 Article en page(s) : pp 1527 - 1542 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatio-temporelle
[Termes IGN] densité
[Termes IGN] données localisées 3D
[Termes IGN] données spatiotemporelles
[Termes IGN] estimation par noyau
[Termes IGN] exploration de données géographiques
[Termes IGN] Finlande
[Termes IGN] navire
[Termes IGN] reconstruction d'itinéraire ou de trajectoire
[Termes IGN] trajectoire (véhicule non spatial)Résumé : (Auteur) Modern positioning and identification technologies enable tracking of almost any type of moving object. A remarkable amount of new trajectory data is thus available for the analysis of various phenomena. In cartography, a typical way to visualise and explore such data is to use a space-time cube, where trajectories are shown as 3D polylines through space and time. With increasingly large movement datasets becoming available, this type of display quickly becomes cluttered and unclear. In this article, we introduce the concept of 3D space-time density of trajectories to solve the problem of cluttering in the space-time cube. The space-time density is a generalisation of standard 2D kernel density around 2D point data into 3D density around 3D polyline data (i.e. trajectories). We present the algorithm for space-time density, test it on simulated data, show some basic visualisations of the resulting density volume and observe particular types of spatio-temporal patterns in the density that are specific to trajectory data. We also present an application to real-time movement data, that is, vessel movement trajectories acquired using the Automatic Identification System (AIS) equipment on ships in the Gulf of Finland. Finally, we consider the wider ramifications to spatial analysis of using this novel type of spatio-temporal visualisation. Numéro de notice : A2010-466 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658816.2010.511223 En ligne : https://doi.org/10.1080/13658816.2010.511223 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30659
in International journal of geographical information science IJGIS > vol 24 n° 10 (october 2010) . - pp 1527 - 1542[article]Réservation
Réserver ce documentExemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2010061 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010062 RAB Revue Centre de documentation En réserve L003 Disponible An ensemble approach to space-time interpolation / E. Wentz in International journal of geographical information science IJGIS, vol 24 n° 9 (september 2010)
[article]
Titre : An ensemble approach to space-time interpolation Type de document : Article/Communication Auteurs : E. Wentz, Auteur ; Donna J. Peuquet, Auteur ; S. Anderson, Auteur Année de publication : 2010 Article en page(s) : pp 1309 - 1325 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatio-temporelle
[Termes IGN] estimation statistique
[Termes IGN] implémentation (informatique)
[Termes IGN] interpolation
[Termes IGN] milieu urbain
[Termes IGN] occupation du sol
[Termes IGN] paramètre de temps
[Termes IGN] Phoenix
[Termes IGN] urbanisationRésumé : (Auteur) The availability of spatial data on an unprecedented scale as well as advancements in analytical and visualization techniques gives researchers the opportunity to study complex problems over large urban and regional areas. Nevertheless, few individual data sets exist that provide both the requisite spatial and/or temporal observational frequency to truly facilitate detailed investigations. Some data are collected frequently over time but only at a few geographic locations (e.g., weather stations). Similarly, other data are collected with a high level of spatial resolution but not at regular or frequent time intervals (e.g., satellite data). The purpose of this article is to present an interpolation approach that leverages the relative temporal richness of one data set with the relative spatial richness of another to fill in the gaps. Because different interpolation techniques are more appropriate than others for specific types of data, we propose a space-time interpolation approach whereby two interpolation methods - one for the temporal and one for the spatial dimension - are used in tandem to increase the accuracy results. We call our ensemble approach the space-time interpolation environment (STIE). The primary steps within this environment include a spatial interpolation processor, a temporal interpolation processor, and a calibration processor, which enforces phenomenon-related behavioral constraints. The specific interpolation techniques used within the STIE can be chosen on the basis of suitability for the data and application at hand. In this article, we first describe STIE conceptually including the data input requirements, output structure, details of the primary steps, and the mechanism for coordinating the data within those steps. We then describe a case study focusing on urban land cover in Phoenix, Arizona, using our working implementation. Our empirical results show that our approach increased the accuracy for estimating urban land cover better than a single interpolation technique. Numéro de notice : A2010-404 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/URBANISME Nature : Article DOI : 10.1080/13658816.2010.488238 En ligne : https://doi.org/10.1080/13658816.2010.488238 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30597
in International journal of geographical information science IJGIS > vol 24 n° 9 (september 2010) . - pp 1309 - 1325[article]Réservation
Réserver ce documentExemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2010051 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010052 RAB Revue Centre de documentation En réserve L003 Disponible Directed movements in probabilistic time geography / Stephan Winter in International journal of geographical information science IJGIS, vol 24 n° 9 (september 2010)
[article]
Titre : Directed movements in probabilistic time geography Type de document : Article/Communication Auteurs : Stephan Winter, Auteur ; Z. Yin, Auteur Année de publication : 2010 Article en page(s) : pp 1349 - 1365 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatio-temporelle
[Termes IGN] cône
[Termes IGN] distribution, loi de
[Termes IGN] incertitude des données
[Termes IGN] modèle stochastique
[Termes IGN] prisme
[Termes IGN] Time-geographyRésumé : (Auteur) This article studies probabilistic time geography for space-time prisms, that is, for situations where observers know the location of an agent at one time and then again at another time. In the intervening period, the agent would have moved freely, according to its time budget. The article demonstrates that the probability of finding the agent somewhere in the space-time prism is not equally distributed, so any attempt of a quantitative time geographic analysis must consider the actual probability distribution. This article develops, implements, and demonstrates this distribution. A preceding article introduced probabilistic time geography for space-time cones. With cones and prisms, the elementary space-time volumes of time geography are provided. Numéro de notice : A2010-405 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658811003619150 En ligne : https://doi.org/https://doi.org/10.1080/13658811003619150 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30598
in International journal of geographical information science IJGIS > vol 24 n° 9 (september 2010) . - pp 1349 - 1365[article]Réservation
Réserver ce documentExemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2010051 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010052 RAB Revue Centre de documentation En réserve L003 Disponible Geometric feature extraction by a multimarked point process / Florent Lafarge in IEEE Transactions on Pattern Analysis and Machine Intelligence, PAMI, vol 32 n° 9 (September 2010)PermalinkContext-based mapping of damaged buildings from high-resolution optical satellite images / T. Vu in International Journal of Remote Sensing IJRS, vol 31 n° 13 (July /2010)PermalinkAn application-driven approach to terrain model construction / A. Darnell in International journal of geographical information science IJGIS, vol 24 n°7-8 (july 2010)PermalinkAn efficient stochastic approach for building footprint extraction from digital elevation models / Olivier Tournaire in ISPRS Journal of photogrammetry and remote sensing, vol 65 n° 4 (July - August 2010)PermalinkApproximating covariance matrices estimated in multivariate models by estimated auto- and cross-covariances / Karl Rudolf Koch in Journal of geodesy, vol 84 n° 6 (June 2010)PermalinkRobust Kalman filtering with constraints: a case study for integrated navigation / Y. Yang in Journal of geodesy, vol 84 n° 6 (June 2010)PermalinkNew results in airborne vector gravimetry using strapdown INS/DGPS / M. Senobari in Journal of geodesy, vol 84 n° 5 (May 2010)PermalinkEstimating crown base height for Scots pine by means of the 3D geometry of airborne laser scanning data / Jari Vauhkonen in International Journal of Remote Sensing IJRS, vol 31 n° 5 (March 2010)PermalinkDetecting negative spatial autocorrelation in georeferenced random variables / Daniel A. Griffith in International journal of geographical information science IJGIS, vol 24 n°3-4 (march 2010)PermalinkHome energy assessment technologies / G. Hay in GIM international, vol 24 n° 3 (March 2010)Permalink