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Explanation for the seam line discontinuity in terrestrial laser scanner point clouds / Derek D. Lichti in ISPRS Journal of photogrammetry and remote sensing, vol 154 (August 2019)
[article]
Titre : Explanation for the seam line discontinuity in terrestrial laser scanner point clouds Type de document : Article/Communication Auteurs : Derek D. Lichti, Auteur ; Craig L. Glennie, Auteur ; Kaleel Al-Durgham, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 59 - 69 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] angle de visée
[Termes IGN] discontinuité
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestreRésumé : (Auteur) The so-called seam line discontinuity is a phenomenon that can be observed in point clouds captured with some panoramic terrestrial laser scanners. It is an angular discontinuity that is most apparent where the lower limit of the instrument’s angular field-of-view intersects the ground. It appears as step discontinuities at the start (0° horizontal direction) and end (180°) of scanning. To the authors’ best knowledge, its cause and its impact, if any, on point cloud accuracy have not yet been reported. This paper presents the results of a rigorous investigation into several hypothesized causes of this phenomenon: differences between the lower and upper elevation angle scanning limits; the presence of a vertical circle index error; and changes in levelling during scanning. New models for the angular observations have been developed and simulations were performed to independently study the impact of each hypothesized cause and to guide the analyses of real datasets. In order to scrutinize each of the hypothesized causes, experiments were conducted with seven real datasets captured with six different instruments: one hybrid-architecture scanner and five panoramic scanners, one of which was also operated as a hybrid instrument. This study concludes that the difference between the elevation angle scanning limits is the source of the seam line discontinuity phenomenon. Accuracy assessment experiments over real data captured in an indoor test facility demonstrate that the seam line discontinuity has no metric impact on the point clouds. Numéro de notice : A2019-264 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.05.012 Date de publication en ligne : 06/06/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.05.012 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93078
in ISPRS Journal of photogrammetry and remote sensing > vol 154 (August 2019) . - pp 59 - 69[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2019081 RAB Revue Centre de documentation En réserve L003 Disponible 081-2019083 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2019082 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt Uncertainty assessment of optical distance measurements at micrometer level accuracy for long-range applications / Joffray Guillory in IEEE Transactions on Instrumentation and Measurement, vol 68 n° 6 (June 2019)
[article]
Titre : Uncertainty assessment of optical distance measurements at micrometer level accuracy for long-range applications Type de document : Article/Communication Auteurs : Joffray Guillory, Auteur ; Maylis Teyssendier de la Serve , Auteur ; Daniel Truong, Auteur ; Christophe Alexandre, Auteur ; Jean-Pierre Wallerand, Auteur Année de publication : 2019 Projets : 2-Pas d'info accessible - article non ouvert / Article en page(s) : pp 2260 - 2267 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] distancemètre
[Termes IGN] incertitude géométrique
[Termes IGN] instrument de mesurage de distances
[Termes IGN] mesurage électronique de distances
[Termes IGN] télémètre laserRésumé : (auteur) We have developed a transportable distance meter based on a 1550-nm laser diode, that is, intensity modulated at 5 GHz. This fiber-based prototype is realized using telecommunication components that are reliable, largely available, and affordable. We have identified and quantified the different sources of error when measuring with this technique a distance between two positions of the same reflector. Minimizing these errors and evaluating their uncertainties lead to a global uncertainty of 4 μm (k = 1) up to 1 km. This value does not include the additional errors caused by the evaluation of the atmospheric parameters. This uncertainty has then been verified over 100 m by comparison with an optical interferometer. The prototype was also tested outdoors over 5.4 km and has shown a resolution of 25 μm for an integration time of 10 ms. Distance measurements for long distances with this prototype are still limited by the air refractive index effect. Nevertheless, we have demonstrated that the uncertainty on optical distances reached with this simple technique is compatible with the future development of a two-wavelength system with air index compensation. Numéro de notice : A2019-279 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TIM.2019.2902804 Date de publication en ligne : 03/04/2019 En ligne : https://doi.org/10.1109/TIM.2019.2902804 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95416
in IEEE Transactions on Instrumentation and Measurement > vol 68 n° 6 (June 2019) . - pp 2260 - 2267[article]Estimating architecture-based metabolic scaling exponents of tropical trees using terrestrial LiDAR and 3D modelling / Alvaro Lau in Forest ecology and management, vol 439 (1 May 2019)
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Titre : Estimating architecture-based metabolic scaling exponents of tropical trees using terrestrial LiDAR and 3D modelling Type de document : Article/Communication Auteurs : Alvaro Lau, Auteur ; Christopher Martius, Auteur ; Harm Bartholomeus, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 132-145 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] allométrie
[Termes IGN] bois sur pied
[Termes IGN] branche (arbre)
[Termes IGN] diamètre des arbres
[Termes IGN] données lidar
[Termes IGN] forêt tropicale
[Termes IGN] Guyana
[Termes IGN] mise à l'échelle
[Termes IGN] modélisation 3D
[Termes IGN] semis de points
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) The geometric structure of tree branches has been hypothesized to relate to the mechanical safety and efficiency of resource transport within a tree. As such, the topology of tree architecture links physical properties within a tree and influences the interaction of the tree with its environment. Prior work suggests the existence of general principles which govern tree architectural patterns across of species and bio-geographical regions. In particular, West, Brown and Enquist (WBE, 1997) and Savage et al. (2010) derive scaling exponents (branch radius scaling ratio and branch length scaling ratio ) from symmetrical branch parameters and from these, an architecture-based metabolic scaling rate () for the whole tree. With this key scaling exponent, the metabolism (e.g., number of leaves, respiration, etc.) of a whole tree, or potentially a group of trees, can be estimated allometrically. Until now, branch parameter values have been measured manually; either from standing live trees or from harvested trees. Such measurements are time consuming, labour intensive and susceptible to subjective errors. Remote sensing, and specifically terrestrial LiDAR (TLS), is a promising alternative, being objective, scalable, and able to collect large quantities of data without destructive sampling. In this paper, we calculated branch length, branch radius, and architecture-based metabolic rate scaling exponents by first using TLS to scan standing trees and then fitting quantitative structure models (TreeQSM) models to 3D point clouds from nine trees in a tropical forest in Guyana. To validate these TLS-derived scaling exponents, we compared them with exponents calculated from direct field measurements of all branches >10 cm at four scales: branch-level, cumulative branch order, tree-level and plot-level. We found a bias on the estimations of and exponents due to a bias on the reconstruction of the branching architecture. Although TreeQSM scaling exponents predicted similar as the manually measured exponents, this was due to the combination of and scaling exponents which were both biased. Also, the manually measured and scaling exponents diverged from the WBE’s theoretical exponents suggesting that trees in tropical environments might not follow the predictions for the symmetrical branching geometry proposed by WBE. Our study provides an alternative method to estimate scaling exponents at both the branch- and tree-level in tropical forest trees without the need for destructive sampling. Although this approach is based on a limited sample of nine trees in Guyana, it can be implemented for large-scale plant scaling assessments. These new data might improve our current understanding of metabolic scaling without harvesting trees. Numéro de notice : A2019-485 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2019.02.019 Date de publication en ligne : 07/03/2019 En ligne : https://doi.org/10.1016/j.foreco.2019.02.019 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93664
in Forest ecology and management > vol 439 (1 May 2019) . - pp 132-145[article]A new method of equiangular sectorial voxelization of single-scan terrestrial laser scanning data and its applications in forest defoliation estimation / Langning Huo in ISPRS Journal of photogrammetry and remote sensing, vol 151 (May 2019)
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Titre : A new method of equiangular sectorial voxelization of single-scan terrestrial laser scanning data and its applications in forest defoliation estimation Type de document : Article/Communication Auteurs : Langning Huo, Auteur ; Xiaoli Zhang, Auteur Année de publication : 2019 Article en page(s) : pp 302 - 312 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] canopée
[Termes IGN] défoliation
[Termes IGN] densité des points
[Termes IGN] régression linéaire
[Termes IGN] télémétrie laser terrestre
[Termes IGN] voxelRésumé : (Auteur) Voxelization is an efficient and frequently used data process that is applied to terrestrial laser scanning (TLS) data to facilitate data management and reduce storage size. In this study, an innovative method of equiangular sectorial voxelization is presented based on the distinctive point distribution characteristic of single-scan TLS. It has the function of containing the same number of laser beams going through each voxel, which results in metrics that can be applied to delineate forest conditions. To verify the effectiveness of the new voxelization method and to illustrate its application, 48 plots and 1098 individual trees with different degrees of defoliation were scanned using single-scan TLS. Their defoliation could be linearly regressed by using only point density metrics derived from this new shape of voxels. A 0.89 R2 value and a 12 RMSE (% of defoliation) were obtained for individual-tree-scale estimation, and a 0.83 R2 value and a 12 RMSE (% of defoliation) were obtained for plot-scale estimation. We conclude that the new voxelization method was effective, and the point density that was thus calculated was an efficient feature that revealed forest attributes. Numéro de notice : A2019-212 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2019.03.018 Date de publication en ligne : 30/03/2019 En ligne : https://doi.org/10.1016/j.isprsjprs.2019.03.018 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92678
in ISPRS Journal of photogrammetry and remote sensing > vol 151 (May 2019) . - pp 302 - 312[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2019051 RAB Revue Centre de documentation En réserve L003 Disponible 081-2019053 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2019052 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt Comparaison de MNT à haute résolution issus de techniques laser et photogrammétriques / Michel Kasser in XYZ, n° 158 (mars 2019)
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Titre : Comparaison de MNT à haute résolution issus de techniques laser et photogrammétriques Type de document : Article/Communication Auteurs : Michel Kasser , Auteur ; Nicolas Delley, Auteur ; Stéphane Cretegny, Auteur Année de publication : 2019 Article en page(s) : pp 17 - 20 Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] analyse comparative
[Termes IGN] image à haute résolution
[Termes IGN] image captée par drone
[Termes IGN] modèle numérique de terrain
[Termes IGN] montagne
[Termes IGN] photogrammétrie aérienne
[Termes IGN] télémétrie laser aéroporté
[Termes IGN] Vaud (Suisse)Résumé : (auteur) Dans le cadre d'une étude génomique de plantes de haute altitude nécessitant des modèles de terrain extrêmement précis, une étude sur les comparaisons de modèles acquis par des outils différents a été menée, ceci dans des sites sans végétation haute. Diverses pistes sont présentées pour expliquer les différences observées. Numéro de notice : A2019-082 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92219
in XYZ > n° 158 (mars 2019) . - pp 17 - 20[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 112-2019011 RAB Revue Centre de documentation En réserve L003 Disponible Modelling the effects of fundamental UAV flight parameters on LiDAR point clouds to facilitate objectives-based planning / Jeremy J. Sofonia in ISPRS Journal of photogrammetry and remote sensing, vol 149 (March 2019)PermalinkSingle-image photogrammetry for deriving tree architectural traits in mature forest stands: a comparison with terrestrial laser scanning / Kamil Kędra in Annals of Forest Science, vol 76 n° 1 (March 2019)PermalinkPermalinkAssessment of along-normal uncertainties for application to terrestrial laser scanning surveys of engineering structures / Tarvo Mill in Survey review, vol 51 n° 364 (January 2019)PermalinkCorrecting for nondetection in estimating forest characteristics from single-scan terrestrial laser measurements / Mikko Kuronen in Canadian Journal of Forest Research, vol 49 n° 1 (janvier 2019)PermalinkPermalinkIs field-measured tree height as reliable as believed – A comparison study of tree height estimates from field measurement, airborne laser scanning and terrestrial laser scanning in a boreal forest / Yunsheng Wang in ISPRS Journal of photogrammetry and remote sensing, vol 147 (January 2019)PermalinkMeasuring stem diameters with TLS in boreal forests by complementary fitting procedure / Timo P Pitkänen in ISPRS Journal of photogrammetry and remote sensing, vol 147 (January 2019)PermalinkPermalinkPermalink