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Empirical stochastic model of detected target centroids: Influence on registration and calibration of terrestrial laser scanners / Tomislav Medic in Journal of applied geodesy, vol 13 n° 3 (July 2019)
[article]
Titre : Empirical stochastic model of detected target centroids: Influence on registration and calibration of terrestrial laser scanners Type de document : Article/Communication Auteurs : Tomislav Medic, Auteur ; Christoph Holst, Auteur ; Jannik Janssen, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2019 Article en page(s) : pp 179 – 197 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] centroïde
[Termes IGN] compensation par moindres carrés
[Termes IGN] détection de cible
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] étalonnage d'instrument
[Termes IGN] incertitude de mesurage
[Termes IGN] métrologie dimensionelle
[Termes IGN] modèle stochastique
[Termes IGN] semis de points
[Termes IGN] télémètre laser terrestreRésumé : (auteur) The target-based point cloud registration and calibration of terrestrial laser scanners (TLSs) are mathematically modeled and solved by the least-squares adjustment. However, usual stochastic models are simplified to a large amount: They generally employ a single point measurement uncertainty based on the manufacturers’ specifications. This definition does not hold true for the target-based calibration and registration due to the fact that the target centroid is derived from multiple measurements and its uncertainty depends on the detection procedure as well. In this study, we empirically investigate the precision of the target centroid detection and define an empirical stochastic model in the form of look-up tables. Furthermore, we compare the usual stochastic model with the empirical stochastic model on several point cloud registration and TLS calibration experiments. There, we prove that the values of usual stochastic models are underestimated and incorrect, which can lead to multiple adverse effects such as biased results of the estimation procedures, a false a posteriori variance component analysis, false statistical testing, and false network design conclusions. In the end, we prove that some of the adverse effects can be mitigated by employing the a priori knowledge about the target centroid uncertainty behavior. Numéro de notice : A2019-284 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1515/jag-2018-0032 Date de publication en ligne : 22/03/2019 En ligne : https://doi.org/10.1515/jag-2018-0032 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93119
in Journal of applied geodesy > vol 13 n° 3 (July 2019) . - pp 179 – 197[article]Large scale semi-automatic detection of forest roads from low density LiDAR data on steep terrain in Northern Spain / Convadonga Prendes in iForest, biogeosciences and forestry, vol 12 n° 4 (July 2019)
[article]
Titre : Large scale semi-automatic detection of forest roads from low density LiDAR data on steep terrain in Northern Spain Type de document : Article/Communication Auteurs : Convadonga Prendes, Auteur ; Sandra Bujan, Auteur ; Celestino Ordóñez, Auteur ; Elena Canga, Auteur Année de publication : 2019 Article en page(s) : pp 366 - 374 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse d'image orientée objet
[Termes IGN] axe médian
[Termes IGN] chemin forestier
[Termes IGN] classification pixellaire
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Espagne
[Termes IGN] montagneRésumé : (auteur) While forest roads are important to forest managers in terms of facilitating the exploitation of wood and timber, their role is far more multifunctional. They permit access to emergency services in the case of forest fires as well as acting as fire breaks, enhance biodiversity, and provide access to the public to enjoy recreational activities. Detailed maps of forest roads are an essential tool for better and more timely forest management and automatic/semi-automatic tools allow not only the creation of forest road databases, but also enable these to be updated. In Spain, LiDAR data for the entire national territory is freely available, and the capture of higher density data is planned in the next few years. As such, the development of a forest road detection methodology based on LiDAR data would allow maps of all forest roads to be developed and regularly updated. The general objective of this work was to establish a low density LiDAR data-based methodology for the semi-automatic detection of the centerline of forest roads on steep terrain with various types of canopy cover. Intensity and slope images were generated using the currently available LiDAR data of the study area (0.5 points m-2). Two image classification approaches were evaluated: pixel-based and object-oriented classification (OBIA). The LiDAR-derived centerlines obtained with the two approaches were compared with the real centerlines which had previously been digitized in the field. The road width, type of surface and type of vegetation cover were also recorded. The effectiveness of the two approaches was evaluated through three quality indicators: correctness, completeness and quality. In addition, the accuracy of the LiDAR-derived centerlines was also evaluated by combining GIS analysis and statistical methods. The pixel-based approach obtained higher values than OBIA for two of the three quality measures (correctness: 93% compared to 90%; and quality: 60% compared to 56%) as well as in terms of positional accuracy (± 5.5 m vs. ± 6.8 for OBIA). The results obtained in this study demonstrate that producing road maps is among the most valuable and easily attainable products of LiDAR data analysis. Numéro de notice : A2019-659 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.3832/ifor2989-012 Date de publication en ligne : 05/07/2019 En ligne : https://doi.org/10.3832/ifor2989-012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98528
in iForest, biogeosciences and forestry > vol 12 n° 4 (July 2019) . - pp 366 - 374[article]Building detection and regularisation using DSM and imagery information / Yousif A. Mousa in Photogrammetric record, vol 34 n° 165 (March 2019)
[article]
Titre : Building detection and regularisation using DSM and imagery information Type de document : Article/Communication Auteurs : Yousif A. Mousa, Auteur ; Petra Helmholz, Auteur ; David Belton, Auteur ; Dimitri Bulatov, Auteur Année de publication : 2019 Article en page(s) : pp 85 - 107 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] détection du bâti
[Termes IGN] extraction automatique
[Termes IGN] masque
[Termes IGN] modèle numérique de surface
[Termes IGN] polygone
[Termes IGN] régularisation
[Termes IGN] simplification de contourRésumé : (Auteur) An automatic method for the regularisation of building outlines is presented, utilising a combination of data‐ and model‐driven approaches to provide a robust solution. The core part of the method includes a novel data‐driven approach to generate approximate building polygons from a list of given boundary points. The algorithm iteratively calculates and stores likelihood values between an arbitrary starting boundary point and each of the following boundary points using a function derived from the geometrical properties of a building. As a preprocessing step, building segments have to be identified using a robust algorithm for the extraction of a digital elevation model. Evaluation results on a challenging dataset achieved an average correctness of 96·3% and 95·7% for building detection and regularisation, respectively. Numéro de notice : A2019-454 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/phor.12275 Date de publication en ligne : 26/03/2019 En ligne : https://doi.org/10.1111/phor.12275 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92867
in Photogrammetric record > vol 34 n° 165 (March 2019) . - pp 85 - 107[article]Central place indexing : hierarchical linear indexing systems for mixed-aperture hexagonal discrete global grid systems / Kevin Sahr in Cartographica, vol 54 n° 1 (Spring 2019)
[article]
Titre : Central place indexing : hierarchical linear indexing systems for mixed-aperture hexagonal discrete global grid systems Type de document : Article/Communication Auteurs : Kevin Sahr, Auteur Année de publication : 2019 Article en page(s) : pp 16 - 29 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] arbre quadratique
[Termes IGN] indexation spatiale
[Termes IGN] polyèdre
[Termes IGN] système de grille globale discrèteRésumé : (Auteur) Hexagonal discrete global grid systems (DGGSs) with integer spatial indexes are a promising new approach to designing geospatial data structures and location reference systems. Central place indexing (CPI) is a class of multi-precision hierarchical linear spatial indexing systems for pure and mixed-aperture hexagonal DGGSs. Definitions for CPI systems are given both on the plane and on the polyhedral surfaces of geodesic DGGSs, and examples of real-world DGGSs indexed using CPI are described. The semantic advantages of CPI systems are discussed, including their ability to exactly represent their own geometries. Numéro de notice : A2019-434 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3138/cart.54.1.2018-0022 Date de publication en ligne : 28/03/2019 En ligne : https://doi.org/10.3138/cart.54.1.2018-0022 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92760
in Cartographica > vol 54 n° 1 (Spring 2019) . - pp 16 - 29[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 031-2019011 SL Revue Centre de documentation Revues en salle Disponible Geographic space as a living structure for predicting human activities using big data / Bin Jiang in International journal of geographical information science IJGIS, Vol 33 n° 3-4 (March - April 2019)
[article]
Titre : Geographic space as a living structure for predicting human activities using big data Type de document : Article/Communication Auteurs : Bin Jiang, Auteur ; Zheng Ren, Auteur Année de publication : 2019 Article en page(s) : pp 764 - 779 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] données issues des réseaux sociaux
[Termes IGN] données massives
[Termes IGN] métadonnées
[Termes IGN] mise à l'échelle
[Termes IGN] OpenStreetMap
[Termes IGN] polygone de Thiessen
[Termes IGN] relation topologique
[Termes IGN] représentation des détails topographiques
[Termes IGN] Royaume-UniRésumé : (Auteur) Inspired by Christopher Alexander’s conception of the world – space is not lifeless or neutral, but a living structure involving far more small things than large ones – a topological representation has been previously developed to characterize the living structure or the wholeness of geographic space. This paper further develops the topological representation and living structure for predicting human activities in geographic space. Based on millions of street nodes of the United Kingdom extracted from OpenStreetMap, we established living structures at different levels of scale in a nested manner. We found that tweet locations at different levels of scale, such as country and city, can be well predicted by the underlying living structure. The high predictability demonstrates that the living structure and the topological representation are efficient and effective for better understanding geographic forms. Based on this major finding, we argue that the topological representation is a truly multiscale representation, and point out that existing geographic representations are essentially single scale, so they bear many scale problems such as modifiable areal unit problem, the conundrum of length and the ecological fallacy. We further discuss on why the living structure is an efficient and effective instrument for structuring geospatial big data, and why Alexander’s organic worldview constitutes the third view of space. Numéro de notice : A2019-215 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2018.1427754 Date de publication en ligne : 31/01/2018 En ligne : https://doi.org/10.1080/13658816.2018.1427754 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92687
in International journal of geographical information science IJGIS > Vol 33 n° 3-4 (March - April 2019) . - pp 764 - 779[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2019031 RAB Revue Centre de documentation En réserve L003 Disponible 079-2019032 RAB Revue Centre de documentation En réserve L003 Disponible Thinking outside the square: Evidence that plot shape and layout in forest inventories can bias estimates of stand metrics / Thomas S. H. Paul in Methods in ecology and evolution, vol 10 n° 3 (March 2019)PermalinkAnalyse de données d’OpenStreetMap en vue de discriminer l’usage du sol lié au bâti / Jocelyn Le Maître (2019)PermalinkPermalinkSimultaneous chain-forming and generalization of road networks / Susanne Wenzel in Photogrammetric Engineering & Remote Sensing, PERS, vol 85 n° 1 (January 2019)PermalinkDEM refinement by low vegetation removal based on the combination of full waveform data and progressive TIN densification / Hongchao Ma in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)PermalinkHistoric reconstruction of reservoir topography using contour line interpolation and structure from motion photogrammetry / Ana Casado in International journal of geographical information science IJGIS, vol 32 n° 11-12 (November - December 2018)PermalinkA topology-preserving polygon rasterization algorithm / Chen Zhou in Cartography and Geographic Information Science, Vol 45 n° 6 (November 2018)PermalinkBoresight calibration of low point density Lidar sensors / Sudhagar Nagarajan in Photogrammetric Engineering & Remote Sensing, PERS, vol 84 n° 10 (October 2018)PermalinkA smooth curve as a fractal under the third definition / Ding Ma in Cartographica, vol 53 n° 3 (Fall 2018)PermalinkThe triangulated affine transformation parameters and barycentric coordinates of Turkish Permanent GPS Network / Kutubuddin Ansari in Survey review, vol 50 n° 362 (August 2018)Permalink