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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
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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 application-driven approach to terrain model construction / A. Darnell in International journal of geographical information science IJGIS, vol 24 n°7-8 (july 2010)
[article]
Titre : An application-driven approach to terrain model construction Type de document : Article/Communication Auteurs : A. Darnell, Auteur ; A. Lovett, Auteur ; J. Barclay, Auteur ; et al., Auteur Année de publication : 2010 Article en page(s) : pp 1171 - 1191 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] analyse de sensibilité
[Termes IGN] erreur géométrique
[Termes IGN] incertitude géométrique
[Termes IGN] lave
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] modèle numérique de surfaceRésumé : (Auteur) Terrain is a surface phenomenon that is measured, modelled, and mapped. However, it is continuously variable and must be simulated by points or mathematical equations that are inherently approximations. The error induced by digitally represented terrain can propagate to surface derivatives and geographical information science (GIS) applications where topography is considered. This can lead to uncertainty in model predictions and the use of data that are unfit for the application to which they are intended. This article outlines the problem of uncertainty in terrain representation and demonstrates the consequences for volcanic mudflow modelling. The response of a simple least-cost single flow algorithm to input parameters was investigated in order to assess output variation from the different sources of input variation. Elevation error was modelled with a probability density function (PDF) and propagated through stochastic simulation (Monte Carlo). Such combined uncertainty and sensitivity analyses enabled a qualitative judgement of the relative significance of elevation error on the flow model prediction. Different methods for terrain model construction were considered and show that supplementing global positioning system (GPS) measurements with information from field notes and reconnaissance photographs greatly improved the model performance and reduced the uncertainty. It is concluded that in terms of validity of model results, there is no substitute for constructing an elevation model that is informed by the terrain. Numéro de notice : A2010-325 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/13658810903318889 En ligne : https://doi.org/10.1080/13658810903318889 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30519
in International journal of geographical information science IJGIS > vol 24 n°7-8 (july 2010) . - pp 1171 - 1191[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010041 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010042 RAB Revue Centre de documentation En réserve L003 Disponible An 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)
[article]
Titre : An efficient stochastic approach for building footprint extraction from digital elevation models Type de document : Article/Communication Auteurs : Olivier Tournaire , Auteur ; Didier Boldo , Auteur ; Mélanie Durupt, Auteur ; Mathieu Brédif , Auteur Année de publication : 2010 Article en page(s) : 11 p. ; pp 317 - 327 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] chaîne de Markov
[Termes IGN] détection du bâti
[Termes IGN] efficacité
[Termes IGN] empreinte
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] milieu urbain
[Termes IGN] modèle numérique de surfaceRésumé : (Auteur) In the past two decades, building detection and reconstruction from remotely sensed data has been an active research topic in the photogrammetric and remote sensing communities. Recently, effective high level approaches have been developed, i.e., the ones involving the minimization of an energetic formulation. Yet, their efficiency has to be balanced by the amount of processing power required to obtain good results. In this paper, we introduce an original energetic model for building footprint extraction from high resolution digital elevation models (?1 m) in urban areas. Our goal is to formulate the energy in an efficient way, easy to parametrize and fast to compute, in order to get an effective process still providing good results. Our work is based on stochastic geometry, and in particular on marked point processes of rectangles. We therefore try to obtain a reliable object configuration described by a collection of rectangular building footprints. To do so, an energy function made up of two terms is defined: the first term measures the adequacy of the objects with respect to the data and the second one has the ability to favour or penalize some footprint configurations based on prior knowledge (alignment, overlapping,...). To minimize the global energy, we use a Reversible Jump Monte Carlo Markov Chain (RJMCMC) sampler coupled with a simulated annealing algorithm, leading to an optimal configuration of objects. Various results from different areas and resolutions are presented and evaluated. Our work is also compared with an already existing methodology based on the same mathematical framework that uses a much more complex energy function. We show how we obtain similarly good results with a high computational efficiency (between 50 and 100 times faster) using a simplified energy that requires a single data-independent parameter, compared to more than 20 inter-related and hard-to-tune parameters. Numéro de notice : A2010-294 Affiliation des auteurs : IGN (1940-2011) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2010.02.002 Date de publication en ligne : 12/03/2010 En ligne : https://doi.org/10.1016/j.isprsjprs.2010.02.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30488
in ISPRS Journal of photogrammetry and remote sensing > vol 65 n° 4 (July - August 2010) . - 11 p. ; pp 317 - 327[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2010041 SL Revue Centre de documentation Revues en salle Disponible Approximating 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)
[article]
Titre : Approximating covariance matrices estimated in multivariate models by estimated auto- and cross-covariances Type de document : Article/Communication Auteurs : Karl Rudolf Koch, Auteur ; H. Kukhlmann, Auteur ; W. Schuh, Auteur Année de publication : 2010 Article en page(s) : pp 383 - 397 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] covariance
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] matrice de covariance
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] modèle linéaireRésumé : (Auteur) Quantities like tropospheric zenith delays or station coordinates are repeatedly measured at permanent VLBI or GPS stations so that time series for the quantities at each station are obtained. The covariances of these quantities can be estimated in a multivariate linear model. The covariances are needed for computing uncertainties of results derived from these quantities. The covariance matrix for many permanent stations becomes large, the need for simplifying it may therefore arise under the condition that the uncertainties of derived results still agree. This is accomplished by assuming that the different time series of a quantity like the station height for each permanent station can be combined to obtain one time series. The covariance matrix then follows from the estimates of the auto- and cross-covariance functions of the combined time series. A further approximation is found, if compactly supported covariance functions are fitted to an estimated autocovariance function in order to obtain a covariance matrix which is representative of different kinds of measurements. The simplification of a covariance matrix estimated in a multivariate model is investigated here for the coordinates of points of a grid measured repeatedly by a laserscanner. The approximations are checked by determining the uncertainty of the sum of distances to the points of the grid. To obtain a realistic value for this uncertainty, the covariances of the measured coordinates have to be considered. Three different setups of measurements are analyzed and a covariance matrix is found which is representative for all three setups. Covariance matrices for the measurements of laserscanners can therefore be determined in advance without estimating them for each application. Numéro de notice : A2010-282 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-010-0375-5 Date de publication en ligne : 19/03/2010 En ligne : https://doi.org/10.1007/s00190-010-0375-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30476
in Journal of geodesy > vol 84 n° 6 (June 2010) . - pp 383 - 397[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2010061 SL Revue Centre de documentation Revues en salle Disponible Détection d'empreintes de bâtiments dans un modèle numérique d'élévation : une approche énergétique / Olivier Tournaire (2010)PermalinkNouvelles méthodes probabilistes pour l'évaluation des risques / B. Beauzamy (2010)PermalinkStructural approach for building reconstruction from a single DSM / Florent Lafarge in IEEE Transactions on Pattern Analysis and Machine Intelligence, PAMI, vol 32 n° 1 (January 2010)PermalinkThe effects of forest structure on the risk of wind damage at a landscape level in a boreal forest ecosystem / Hongcheng Zeng in Annals of Forest Science, vol 67 n° 1 (January-February 2010)PermalinkAmundsen Sea bathymetry: the benefits of using gravity data for bathymetric prediction / M. Mcmillan in IEEE Transactions on geoscience and remote sensing, vol 47 n° 12 Tome 2 (December 2009)PermalinkVers une nouvelle représentation des déformations horizontales de la croûte terrestre et de leurs erreurs avec un champ régulier de tenseurs / Leila Eissa in XYZ, n° 121 (décembre 2009 - février 2010)PermalinkPermalinkA geometric stochastic approach based on marked point processes for road mark detection from high resolution aerial images / Olivier Tournaire in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 6 (November - December 2009)PermalinkSensivity analysis of a decision tree classification to input data errors using a general Monte Carlo error sensitivity model / Zhi Huang in International journal of geographical information science IJGIS, vol 23 n°11-12 (november 2009)PermalinkProblèmes inverses en imagerie et en vision, 1. Volume 1 / A. Mohammad-Djafari (2009)Permalink