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A graph-based approach for the structural analysis of road and building layouts / Mathieu Domingo in Geo-spatial Information Science, vol 22 n° 1 (March 2019)
[article]
Titre : A graph-based approach for the structural analysis of road and building layouts Type de document : Article/Communication Auteurs : Mathieu Domingo, Auteur ; Rémy Thibaud, Auteur ; Christophe Claramunt, Auteur Année de publication : 2019 Article en page(s) : pp 59 - 72 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] bati
[Termes IGN] distance
[Termes IGN] espace urbain
[Termes IGN] graphe
[Termes IGN] réseau routierRésumé : (Auteur) A better understanding of the relationship between the structure and functions of urban and suburban spaces is one of the avenues of research still open for geographical information science. The research presented in this paper develops several graph-based metrics whose objective is to characterize some local and global structural properties that reflect the way the overall building layout can be cross-related to the one of the road layout. Such structural properties are modeled as an aggregation of parcels, buildings, and road networks. We introduce several computational measures (Ratio Minimum Distance, Minimum Ratio Minimum Distance, and Metric Compactness) that respectively evaluate the capability for a given road to be connected with the whole road network. These measures reveal emerging sub-network structures and point out differences between less-connective and more-connective parts of the network. Based on these local and global properties derived from the topological and graph-based representation, and on building density metrics, this paper proposes an analysis of road and building layouts at different levels of granularity. The metrics developed are applied to a case study in which the derived properties reveal coherent as well as incoherent neighborhoods that illustrate the potential of the approach and the way buildings and roads can be relatively connected in a given urban environment. Overall, and by integrating the parcels and buildings layouts, this approach complements other previous and related works that mainly retain the configurational structure of the urban network as well as morphological studies whose focus is generally limited to the analysis of the building layout. Numéro de notice : A2019-242 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10095020.2019.1568736 Date de publication en ligne : 15/02/2019 En ligne : https://doi.org/10.1080/10095020.2019.1568736 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92936
in Geo-spatial Information Science > vol 22 n° 1 (March 2019) . - pp 59 - 72[article]A new waveform decomposition method for multispectral LiDAR / Shalei Song in ISPRS Journal of photogrammetry and remote sensing, vol 149 (March 2019)
[article]
Titre : A new waveform decomposition method for multispectral LiDAR Type de document : Article/Communication Auteurs : Shalei Song, Auteur ; Binhui Wang, Auteur ; Wei Gong, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 40 - 49 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] couvert végétal
[Termes IGN] décomposition de Gauss
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] extraction de la végétation
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] forme d'onde pleine
[Termes IGN] transformation en ondelettesRésumé : (Auteur) Information derived from waveform decomposition of full-waveform light detection and ranging (LiDAR) data has been widely used in vegetation detection and three-dimensional urban terrain modeling to investigate and interpret the structural diversity of surface coverage. Most prevailing waveform decomposition methods involve only a single wavelength, but these methods do not apply to full-waveform multispectral LiDAR (FWMSL) systems that simultaneously acquire spectral and geometric information. In this paper, we propose a new multispectral waveform decomposition (MSWD) method in order to explore the potential advantages of the FWMSL system. Both simulated data and measured data from our FWMSL system were used to evaluate the performance of the proposed method. The coefficient of determination (R2), root mean square error (RMSE), and relative error (rRMSE) metrics suggest that the decomposition results derived from MSWD exhibit a comparable overall fitting accuracy as a single wavelength waveform decomposition (SWWD) method. We also propose a new evaluation indicator, relative neighbor distance error (RNDE), to represent the relative error in the distance between adjacent targets. The simulation results present clear superiority of MSWD over SWWD in terms of discovering weak or overlapping components and retrieving accurate waveform parameters. The experimental results demonstrated a considerable improvement in RNDE (0.0100–0.0610) over the prevailing SWWD method (0.0566–0.2833). Unlike SWWD, MSWD initializes waveform components using mutually complementary wavelengths thus delivering higher completeness and accuracy. MSWD can be extended to other FWMSL or full-waveform hyperspectral LiDAR systems with additional wavelengths. Numéro de notice : A2019-127 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.01.014 Date de publication en ligne : 22/01/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.01.014 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92438
in ISPRS Journal of photogrammetry and remote sensing > vol 149 (March 2019) . - pp 40 - 49[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2019031 RAB Revue Centre de documentation En réserve L003 Disponible 081-2019033 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2019032 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt 3D radiative transfer modeling over complex vegetation canopies and forest reconstruction from LIDAR measurements / Jianbo Qi (2019)
Titre : 3D radiative transfer modeling over complex vegetation canopies and forest reconstruction from LIDAR measurements Type de document : Thèse/HDR Auteurs : Jianbo Qi, Auteur ; Jean-Philippe Gastellu-Etchegorry, Directeur de thèse ; Guangjian Yan, Directeur de thèse Editeur : Toulouse : Université de Toulouse 3 Paul Sabatier Année de publication : 2019 Importance : 154 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse en vue de l'obtention du Doctorat de l'Université de Toulouse, Surfaces et interfaces continentales, hydrologieLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] couvert végétal
[Termes IGN] données lidar
[Termes IGN] forêt
[Termes IGN] indice foliaire
[Termes IGN] interface graphique
[Termes IGN] milieu anisotrope
[Termes IGN] modèle de transfert radiatif
[Termes IGN] modélisation 3D
[Termes IGN] rendu réaliste
[Termes IGN] scène 3D
[Termes IGN] semis de pointsIndex. décimale : THESE Thèses et HDR Résumé : (auteur) Remote sensing is needed for better managing vegetation covers. Hence, three-dimensional (3D) radiative transfer (RT) modeling is essential for understanding remote sensing signals of complex 3D vegetation covers. Due to the complexity of 3D models, one-dimensional (1D) RT models are commonly used to retrieve vegetation parameters, e.g., leaf area index (LAI), from remote sensing data. However, 1D models are not adapted to actual vegetation covers because they abstract them as schematic 1D layers, which is not realistic. Much effort is devoted to the conception of 3D RT models that can consider the 3D architecture of vegetation covers. However, developing an efficient 3D RT model that works on large and realistic scenes is still a challenging task. Major difficulties are the intensive computational costs of 3D RT simulation and the acquisition of detailed 3D canopy structures. Therefore, 3D RT models usually only work on abstracted scenes or small realistic scenes. Scene abstraction may cause uncertainties, and the small-scale approach is not compatible with most satellite observations (e.g., MODIS). The computer graphics community provides the most accurate and efficient models (i.e., renderers). However, the initial renderer models were not designed for accurate RT modeling, which explains the difficulty to use them for remote sensing applications. Recently emerged advanced techniques in computer graphics and light detection and ranging area (LiDAR) make it more possible to solve the above problems. 3D RT can be greatly accelerated due to the increasing computer power and improvement of rendering algorithms (e.g., ray-tracing acceleration and computational optimization). Also, 3D high-resolution information from LiDARs and photogrammetry become more accessible to reconstruct realistic 3D scenes. This approach requires new processing methods to combine 3D information and 3D RT models, which is of great importance for better remote sensing survey of vegetation. This thesis is focused on 1) Development of a 3D RT model based on recent ray-tracing techniques and 2) Retrieval of 3D leaf volume density (LVD) for constructing 3D forest scenes. This first chapter presents the development of an efficient 3D RT model, named LESS (LargE-Scale remote sensing data and image Simulation framework). LESS makes full use of ray-tracing algorithms. Specifically, it simulates multispectral BRF and scene radiative budget with a weighted forward photon tracing method, and sensor images (e.g., fisheye images) or large-scale (e.g. 1 km2) spectral images are simulated with a backward path tracing method. In the forward mode, a "virtual photon" algorithm is used to simulate accurate BRF with few photons. The backward mode is used to simulate thermal infrared images and also atmosphere RT. LESS efficiency and accuracy were demonstrated with a model intercomparison and field measurements. In addition, LESS has an easy-to-use graphic user interface (GUI) to input parameters, construct and visualize 3D scenes. 3D forest reconstruction is done with a simulated LiDAR dataset to assess approaches that retrieve LVD from airborne LiDAR data. The dataset is simulated with the discrete anisotropic radiative transfer model (DART). Note de contenu : 1- Introduction
2- LESS: Ray-tracing based 3D radiative transfer model
3- Accuracy evaluation of LESS
4- Hybrid scene structuring for accelerating 3D radiative transfer
5- Physical interpretation of leaf area index from LiDAR data
6- Voxel-based reconstruction and simulation of 3D forest scene
7- Conclusions and perspectivesNuméro de notice : 25915 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Surfaces et interfaces continentales, hydrologie : Toulouse 3 : 2019 Organisme de stage : CESBIO nature-HAL : Thèse DOI : sans En ligne : https://hal.science/tel-02498603 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96024 Analyse de données d’OpenStreetMap en vue de discriminer l’usage du sol lié au bâti / Jocelyn Le Maître (2019)
Titre : Analyse de données d’OpenStreetMap en vue de discriminer l’usage du sol lié au bâti Type de document : Mémoire Auteurs : Jocelyn Le Maître Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2019 Importance : 24 p. Note générale : Rapport de stage [de février dans le cadre du] Cycle Ingénieur troisième année, Carthagéo Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] bati
[Termes IGN] classification
[Termes IGN] OpenStreetMap
[Termes IGN] polygone
[Termes IGN] traitement de données localisées
[Termes IGN] utilisation du solIndex. décimale : TDE Travaux dirigés des étudiants, rapports de projets, rapports de stage hors fin d'études Résumé : (auteur) [introduction] Le projet Européen Landsense a entre autres pour but d’évaluer les pratiques actuelles au niveau de l’utilisation et la couverture des sols, et en particulier d’évaluer les observatoires collaboratifs. Plus spécifiquement, ce stage a pour but, à partir de données tirées de la plateforme collaborative OpenStreetMap, de séparer dans les données d’Occupation du Sol à Grande Echelle (OCS GE) la classe d’usage du sol US235 en trois sous classes. En effet, comme ces données sont fabriquées à partir d’orthophotographies, il est difficile de distinguer le bâti secondaire du tertiaire ou du résidentiel. Ainsi, l’objectif du stage va être d’obtenir, à partir des informations que l’on peut trouver dans OpenStreetMap, des informations supplémentaires sur le bâti. [...] Nous allons en premier lieu nous attarder sur les données que nous avons à disposition, celles qui devront être déterminées ainsi que celles nous aidant à la faire. Ensuite, nous allons expliquer la démarche suivie pour la classification et enfin, qualifier le modèle obtenu grâce à l’analyse de certaines zones sur OpenStreetMap, ainsi que le résultat global de la classification par rapport à celle réalisée par le Cerema. Note de contenu : 1 Récupération des données
1-1 Les données à classifier
1-2 Les données d’OSM
2 La procédure employée
2-1 Identifier les données pertinentes à récupérer
2-2 Exploitation des données OSM
2-3 Critères d’attribution à une couche pour un polygone
3 Mise en place de tris et évaluation
3-1 Les tris, résultats de classifications
3-2 Evaluation des résultats
3-3 Pistes d’améliorationNuméro de notice : 14369 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : TD/TP étudiant Organisme de stage : IGN DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99156 Documents numériques
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Analyse de données d’OpenStreetMap ... - pdf auteurAdobe Acrobat PDF Archival aerial photogrammetric surveys, a data source to study land use/cover evolution over the last century : opportunities and issues / Arnaud Le Bris (2019)
Titre : Archival aerial photogrammetric surveys, a data source to study land use/cover evolution over the last century : opportunities and issues Type de document : Article/Communication Auteurs : Arnaud Le Bris , Auteur ; Sébastien Giordano , Auteur Editeur : Leibniz : Leibniz Institute of Ecological Urban and Regional Development Année de publication : 2019 Conférence : ILUS 2019, 3rd International land use symposium, Land use changes: Trends and projections 04/12/2019 06/12/2019 Paris France programme sans actes Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] automatisation
[Termes IGN] chaîne de traitement
[Termes IGN] détection de changement
[Termes IGN] égalisation radiométrique
[Termes IGN] géoréférencement indirect
[Termes IGN] image numérisée
[Termes IGN] modèle numérique de surface
[Termes IGN] occupation du sol
[Termes IGN] orientation absolue
[Termes IGN] orthoimage
[Termes IGN] orthophotoplan argentique
[Termes IGN] vingtième siècleRésumé : (auteur) Images from archival aerial photogrammetric surveys are a unique and relatively unexplored means to chronicle 3D land-cover changes occurred since the mid20th century. They provide a relatively dense temporal sampling of the territories with very high spatial resolution. Thus, they offer time series data which can answer to a large variety of long-term environmental monitoring studies. Besides, they are generally stereoscopic surveys, making it possible to derive 3D information (Digital Surface Models). In recent years, they have often been digitized, making them more suitable to be considered in automatic analyses processes. For instance, IGN (the French national mapping agency) has digitized its archival aerial photogrammetric surveys: images can be downloaded from a web service (http://remonterletemps.ign.fr/) Thus, archival aerial photogrammetric surveys appear as being a powerful remote sensing data source to study land use/cover evolution over the last century. However, several difficulties have to be faced to be able to use them in automatic analysis processes. A first bottleneck for accurate comparison between epochs is their fine georeferencing. Such information has generally been lost and must be retrieved. No fully automatic method has been proposed yet and existing studies are rather limited in terms of area and number of dates. State-of-the-art shows that one major challenge is the identification of ground references: cartographic coordinates and their position in the archival images. This task is often manually performed, and extremely time-consuming. This contribution proposes to use a photogrammetric approach, and states that the 3D information that can be computed is the key to full automation. Its original idea lies in a the use of the coarse absolute image orientation from existing metadata to derive coarse Digital Surface Model (DSM) and orthoimage that are then used to improve absolute image orientation. It only relies on a recent orthoimage+DSM, used as master reference for all epochs. The coarse orthoimage, compared with such a reference, allows the identification of dense ground references and the coarse DSM provides their position in the archival images. A new iteration of the georeferencing process can then be done using these ground references. At the end, images orientation is retrieved and orthoimages as well as digital surface models can be computed for each epoch. Another issue is the radiometric equalization of images (to remove atmospheric as well as vignetting effects), in order to obtain a homogeneous mosaic suitable with automatic classification processes. Last but not least, surveys available on a study area can exhibit very different characteristics: survey pattern, focal, spatial resolution, modality (panchromatic, color, infrared...). Planimetric and altimetric accuracies of derived products depend on these characteristics. Thus, automatic change detection and analysis processes have to cope with these uncertainties. Numéro de notice : C2019-069 Affiliation des auteurs : LASTIG MATIS (2012-2019) Thématique : IMAGERIE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97024 Climate variability and climate change impacts on land surface, hydrological processes and water management / Yongqiang Zhang (2019)PermalinkCorrecting rural building annotations in OpenStreetMap using convolutional neural networks / John E. Vargas-Muñoz in ISPRS Journal of photogrammetry and remote sensing, vol 147 (January 2019)PermalinkPermalinkL'imperfection des données géographiques, 1. Bases théoriques / Mireille Batton-Hubert (2019)PermalinkInternational workshop on large scale land cover mapping from remote sensing, 3 décembre 2019 / Mathieu Fauvel (2019)PermalinkMachine learning and geographic information systems for large-scale mapping of renewable energy potential / Dan Assouline (2019)PermalinkMultimodal scene understanding: algorithms, applications and deep learning, ch. 11. Decision fusion of remote-sensing data for land cover classification / Arnaud Le Bris (2019)PermalinkRetrieving relevant land cover and land use data to study urban climate change / Bénédicte Bucher (2019)PermalinkSensitivity of urban material classification to spatial and spectral configurations from visible to short-wave infrared / Arnaud Le Bris (2019)PermalinkSimultaneous chain-forming and generalization of road networks / Susanne Wenzel in Photogrammetric Engineering & Remote Sensing, PERS, vol 85 n° 1 (January 2019)Permalink