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Assessing the contribution of woody materials to forest angular gap fraction and effective leaf area index using terrestrial laser scanning data / Guang Zheng in IEEE Transactions on geoscience and remote sensing, vol 54 n° 3 (March 2016)
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Titre : Assessing the contribution of woody materials to forest angular gap fraction and effective leaf area index using terrestrial laser scanning data Type de document : Article/Communication Auteurs : Guang Zheng, Auteur ; Lixia Ma, Auteur ; Wei He, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 1475 - 1487 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] bois sur pied
[Termes IGN] classification automatique
[Termes IGN] distribution spatiale
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] indice foliaire
[Termes IGN] Leaf Area Index
[Termes IGN] photosynthèse
[Termes IGN] régression linéaire
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestreRésumé : (Auteur) The spatial distribution of the photosynthetic components of a forest canopy plays a key role in ecological related processes such as gas exchange, photosynthesis, and evapotranspiration through affecting radiation regimes of the forest canopy. However, quantitative evaluation of woody materials' contribution to effective leaf area index (LAIe) using 3-D terrestrial laser scanning (TLS) is a challenging work. In this paper, we first identified the differences between directional gap fraction (DGF) and angular gap fraction (AGF) and then developed a local geometric feature-based approach to automatically classify a TLS forest point cloud data (PCD) into three different classes, including nonphotosynthetic canopy components (i.e., stem and branch points), photosynthetic canopy components (i.e., leaf and grass points), and bare ground. In addition, we proposed a new approach named “radial hemispherical point cloud slicing” algorithm to investigate the 3-D spatial distribution of foliage elements and retrieve LAIe from a given forest PCD. Our results showed that nonphotosynthetic canopy components contributed from 19% to 54% to LAIe depending on various forest densities. Moreover, TLS-based LAIe estimates can explain 74.27% variations of digital-hemispherical-photography-based LAIe values with a linear regression statistical model. This paper provides a theoretical foundation for LAI estimation based on the PCD generated using the TLS system and facilitates the application of TLS on retrieving 3-D forest canopy structural biophysical parameters. Numéro de notice : A2016-132 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2481492 En ligne : http://dx.doi.org/10.1109/TGRS.2015.2481492 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80019
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 3 (March 2016) . - pp 1475 - 1487[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2016031 SL Revue Centre de documentation Revues en salle Disponible Challenges and present fields of action at laser scanner based deformation analyses / Christoph Holst in Journal of applied geodesy, vol 10 n° 1 (March 2016)
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Titre : Challenges and present fields of action at laser scanner based deformation analyses Type de document : Article/Communication Auteurs : Christoph Holst, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2016 Article en page(s) : pp 17 -25 Note générale : bibilographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] corrélation automatique de points homologues
[Termes IGN] déformation géométrique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] erreur systématique
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) Due to improved laser scanning technology, laser scanner based deformation analyses are presently widespread. These deformation analyses are no longer based on individual points representing the deformation of an object at selected positions. Instead, they are based on a large number of scan points sampling the whole object. This fact either leads to challenges regarding metrological aspects as well as regarding modeling aspects:
– Estimating and quantifying spatial correlations between scan points and incorporating them into the deformation analysis
– Separating the laser scanners’ internal systematic errors from areal deformations
– Minimizing the bias at areal deformation analyses due to a worse network configuration and limited object knowledge
– Developing freeform parameterizations to reproduce arbitrary areal deformations of an object by individual parameters
– Incorporating an extended uncertainty model considering also model errors due to imperfect knowledge and simplification of the sampled object.
– Only when considering all of these aspects, laser scanner based deformation analyses can benefit from the potential of the areal object sampling. This study aims at naming and reasoning these aspects. Furthermore, it introduces first methodologies and approaches for dealing with them.Numéro de notice : A2016-550 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0025 En ligne : http://dx.doi.org/10.1515/jag-2015-0025 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81694
in Journal of applied geodesy > vol 10 n° 1 (March 2016) . - pp 17 -25[article]Correction of terrestrial LiDAR intensity channel using Oren–Nayar reflectance model: An application to lithological differentiation / Dario Carrea in ISPRS Journal of photogrammetry and remote sensing, vol 113 (March 2016)
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Titre : Correction of terrestrial LiDAR intensity channel using Oren–Nayar reflectance model: An application to lithological differentiation Type de document : Article/Communication Auteurs : Dario Carrea, Auteur ; Antonio Abellan, Auteur ; Florian Humair, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 17 - 29 Note générale : bibliothèque Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] angle d'incidence
[Termes IGN] correction d'image
[Termes IGN] distance euclidienne
[Termes IGN] données lidar
[Termes IGN] réflectance du sol
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestre
[Termes IGN] test de performanceRésumé : (auteur) Ground-based LiDAR has been traditionally used for surveying purposes via 3D point clouds. In addition to XYZ coordinates, an intensity value is also recorded by LiDAR devices. The intensity of the backscattered signal can be a significant source of information for various applications in geosciences.
Previous attempts to account for the scattering of the laser signal are usually modelled using a perfect diffuse reflection. Nevertheless, experience on natural outcrops shows that rock surfaces do not behave as perfect diffuse reflectors. The geometry (or relief) of the scanned surfaces plays a major role in the recorded intensity values.
Our study proposes a new terrestrial LiDAR intensity correction, which takes into consideration the range, the incidence angle and the geometry of the scanned surfaces. The proposed correction equation combines the classical radar equation for LiDAR with the bidirectional reflectance distribution function of the Oren–Nayar model. It is based on the idea that the surface geometry can be modelled by a relief of multiple micro-facets. This model is constrained by only one tuning parameter: the standard deviation of the slope angle distribution (σslope) of micro-facets.
Firstly, a series of tests have been carried out in laboratory conditions on a 2 m2 board covered by black/white matte paper (perfect diffuse reflector) and scanned at different ranges and incidence angles. Secondly, other tests were carried out on rock blocks of different lithologies and surface conditions. Those tests demonstrated that the non-perfect diffuse reflectance of rock surfaces can be practically handled by the proposed correction method.
Finally, the intensity correction method was applied to a real case study, with two scans of the carbonate rock outcrop of the Dents-du-Midi (Swiss Alps), to improve the lithological identification for geological mapping purposes. After correction, the intensity values are proportional to the intrinsic material reflectance and are independent from range, incidence angle and scanned surface geometry. The corrected intensity values significantly improve the material differentiation.Numéro de notice : A2016-532 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.12.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2015.12.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81616
in ISPRS Journal of photogrammetry and remote sensing > vol 113 (March 2016) . - pp 17 - 29[article]Laser scanning based growth analysis of plants as a new challenge for deformation monitoring / Jan Dupuis in Journal of applied geodesy, vol 10 n° 1 (March 2016)
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Titre : Laser scanning based growth analysis of plants as a new challenge for deformation monitoring Type de document : Article/Communication Auteurs : Jan Dupuis, Auteur ; Christoph Holst, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2016 Article en page(s) : pp 37 - 44 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] B-Spline
[Termes IGN] croissance végétale
[Termes IGN] déformation géométrique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] feuille (végétation)
[Termes IGN] maillage par triangles
[Termes IGN] semis de points
[Termes IGN] tessellationRésumé : (auteur) Nowadays, the areal deformation analysis has become an important task in engineering geodesy. Thereby, not only manmade objects are of high interest, also natural objects, like plant organs, are focused more frequently. Thus, the analysis of leaf growth, i. e. the spatial development of the leaf surface, can be seen as a problem of deformation monitoring. In contrast to classical geodetic tasks, the absolute size of the deformation of the leaf surface is small, but usually great compared to the object size. Due to the optical characteristics of leaf surfaces, the point clouds, commonly acquired with high precision close-up laser scanners, provide a point-to-point distance that is small or equal compared to the measurement accuracy. Thus, the point clouds are usually processed and the leaf area is derived from a triangulation-based surface representation (mesh), resulting in a significant uncertainty of area calculation. In this paper, we illustrate the lacks of the mesh-based leaf area calculation. Using high precision gauge blocks as well as a number of tomato leaves, uncertainties of the area derivation are revealed and evaluated. The application of a B-spline approximation illustrates the advantages of an approximation-based approach and introduces the prospect for further research. Numéro de notice : A2016-552 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1515/jag-2015-0028 En ligne : http://dx.doi.org/10.1515/jag-2015-0028 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81698
in Journal of applied geodesy > vol 10 n° 1 (March 2016) . - pp 37 - 44[article]Lasergrammétrie sous-marine : Quel apport pour les métrologies et l’Exploration Production ? / Yann Morel in XYZ, n° 146 (mars - mai 2016)
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Titre : Lasergrammétrie sous-marine : Quel apport pour les métrologies et l’Exploration Production ? Type de document : Article/Communication Auteurs : Yann Morel, Auteur Année de publication : 2016 Article en page(s) : pp 40 - 44 Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] lever bathymétrique
[Termes IGN] photogrammétrie sous-marine
[Termes IGN] télémétrie laser
[Termes IGN] traitement de donnéesRésumé : (auteur) En topographie, la lasergrammétrie est une technologie très largement utilisée pour les opérations terrestres et aériennes. Elle connaît cependant un récent développement pour son déploiement sous-marin. l'objectif de ce projet est d'étudier ce que la lasergrammétrie sous-marine peut apporter au sein de l'Exploration Production du groupe Total. Dans ce rapport, les métrologies sous-marines, qui sont généralement réalisées par méthode acoustique ou à l'aide d'une centrale inertielle, seront particulièrement abordées. Il existe actuellement deux types de scanners laser sous-marins : les scanners laser à temps de vol et à triangulation. Afin d'évaluer cette technologie, ce rapport développera aussi un essai qui a pu être mis en place ou cours du mois de juin 2015. Il a été effectué en Angola, à l'aide d'un scanner laser à temps de vol développé par 3D@Depth. Ce projet a ainsi permis à Total de valider cette technologie et ainsi de l'envisager pour les futurs appels d'offres. Numéro de notice : A2016-258 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80791
in XYZ > n° 146 (mars - mai 2016) . - pp 40 - 44[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 112-2016011 RAB Revue Centre de documentation En réserve L003 Disponible Documents numériques
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Lasergrammétrie sous-marine - pdf éditeurAdobe Acrobat PDFOctree-based segmentation for terrestrial LiDAR point cloud data in industrial applications / Yun-Ting Su in ISPRS Journal of photogrammetry and remote sensing, vol 113 (March 2016)
PermalinkQualification de la précision de données topographiques issues d’acquisitions par méthode scanner laser dynamique ferroporté / Audrey Jacquin in XYZ, n° 146 (mars - mai 2016)
PermalinkRegional scale rain-forest height mapping using regression-kriging of spaceborne and airborne Lidar data: application on French Guiana / Ibrahim Fayad in Remote sensing, vol 8 n° 3 (March 2016)
PermalinkRobust spatial approximation of laser scanner point clouds by means of Free-form Curve approaches in deformation analysis / Johannes Bureick in Journal of applied geodesy, vol 10 n° 1 (March 2016)
PermalinkPermalinkQuantification of overnight movement of birch (Betula pendula) branches and foliage with short interval terrestrial laser scanning / Eetu Puttonen in Frontiers in plant science, vol 7 (29 February 2016)
PermalinkImproved salient feature-based approach for automatically separating photosynthetic and nonphotosynthetic components within terrestrial Lidar point cloud data of forest canopies / Lixia Ma in IEEE Transactions on geoscience and remote sensing, vol 54 n° 2 (February 2016)
PermalinkIs waveform worth it? A comparison of LiDAR approaches for vegetation and landscape characterization / Karen Anderson in Remote sensing in ecology and conservation, vol 2 n° 1 (February 2016)
PermalinkLarge-scale road detection in forested mountainous areas using airborne topographic lidar data / António Ferraz in ISPRS Journal of photogrammetry and remote sensing, vol 112 (February 2016)
PermalinkObject classification and recognition from mobile laser scanning point clouds in a road environment / Matti Lehtomäki in IEEE Transactions on geoscience and remote sensing, vol 54 n° 2 (February 2016)
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