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SNCF Réseau : de l'acquisition 3D à la diffusion de la donnée / Mathieu Regul in XYZ, n° 153 (décembre 2017 - février 2018)
[article]
Titre : SNCF Réseau : de l'acquisition 3D à la diffusion de la donnée Type de document : Article/Communication Auteurs : Mathieu Regul, Auteur ; Franck Richard, Auteur ; Jean-Christophe Michelin , Auteur ; Bruno Landes, Auteur Année de publication : 2017 Article en page(s) : pp 39 - 44 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] diffusion de données
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] interopérabilité
[Termes IGN] précision relative
[Termes IGN] semis de points
[Termes IGN] visualisation 3DRésumé : (Auteur) Les acquisitions 3D par scanner laser ne sont plus une nouveauté pour bon nombre de géomètres. Cette méthode est très répandue pour réaliser une collecte de données rapide et exhaustive. Les constantes évolutions matérielles permettent de meilleurs rendements tant sur le terrain qu'au bureau, rendant ces appareils de plus en plus intéressants. Par ailleurs la baisse des prix constatée depuis peu sur de tels équipements rend cette technologie plus accessible même à de petites entreprises. Les atouts d'un nuage de points 3D ne sont plus à démontrer. En effet l'exhaustivité d'une acquisition 3D permet de garantir que les éléments nécessaires seront relevés. Les traitements sont pour l'heure encore chronophages et demandent parfois des connaissances très spécifiques (dans le cas de reports d'éléments architecturaux et d'éléments d'infrastructure ferroviaire par exemple). Le gros point noir de cette technologie reste la taille conséquente des nuages de points 3D qui limite fortement les capacités d'échanges de données entre services et limite leurs exploitations aux services topographiques (souvent les seuls à être équipés des logiciels et des ordinateurs adéquats). Cet article présente l'utilisation des acquisitions 3D à SNCF Réseau ainsi que les outils mis en place pour mettre à disposition et diffuser les nuages de points 3D aux différentes entités de la société. Numéro de notice : A2017-795 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89105
in XYZ > n° 153 (décembre 2017 - février 2018) . - pp 39 - 44[article]Réservation
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SNCF Réseau ... - pdf éditeurAdobe Acrobat PDF Suivi topographique côtier au moyen d’un système LiDAR mobile terrestre : exemple d’une recharge sédimentaire de plage / Stéfanie Van-Wierts in Geomatica, vol 71 n° 4 (December 2017)
[article]
Titre : Suivi topographique côtier au moyen d’un système LiDAR mobile terrestre : exemple d’une recharge sédimentaire de plage Type de document : Article/Communication Auteurs : Stéfanie Van-Wierts, Auteur ; Pascal Bernatchez, Auteur ; Christian Larouche, Auteur Année de publication : 2017 Article en page(s) : pp 194 - 212 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] littoral
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] précision altimétrique
[Termes IGN] sédiment
[Termes IGN] trait de côteRésumé : (Auteur) L’évolution côtière est complexe, notamment par la migration de la ligne de rivage et l’apparition successive de zones d’érosion ou d’accumulation. Les suivis quantitatifs des systèmes côtiers sont largement utilisés afin de comprendre leurs évolutions temporelle et spatiale. Plusieurs méthodes d’acquisition topographiques ont été utilisées (GNSS RTK, LiDAR aéroporté et LiDAR terrestre statique ou mobile) où chaque méthode présente des avantages et des inconvénients lors de suivis d’environnements côtiers. L’objectif de cet article est de quantifier la précision d’un système LiDAR mobile (SLM) terrestre et d’évaluer s’il peut répondre aux principaux défis des levés topographiques en milieu côtier qui consistent à réaliser des levés à une haute résolution temporelle, à moindre coût, tout en assurant une bonne précision altimétrique et une bonne résolution spatiale. Les résultats montrent que la résolution spatiale est centimétrique et que la précision altimétrique est de 0,039 m (RMS calculé sur 124 points de contrôle). La haute précision altimétrique et la haute résolution spatiale permettent de maximiser la précision des calculs de volume sédimentaire et ainsi diminuer les coûts associés à l’erreur de calcul, notamment lors de projets de recharge sédimentaire de plage. Cela permet aussi d’assurer le positionnement exact de limites marégraphiques et géomorphologiques. En comparaison à des profils topographiques obtenus par méthodes classiques, la forte densité des nuages de points observés avec un SLM permet de cartographier des formes morphologiques de faible amplitude diminuant ainsi l’erreur due à l’interpolation. Numéro de notice : A2017-849 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.5623/cig2017-402 En ligne : https://doi.org/10.5623/cig2017-402 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89447
in Geomatica > vol 71 n° 4 (December 2017) . - pp 194 - 212[article]Terrestrial laser scanning reveals differences in crown structure of Fagus sylvatica in mixed vs. pure European forests / Ignacio Barbeito in Forest ecology and management, vol 405 (1 December 2017)
[article]
Titre : Terrestrial laser scanning reveals differences in crown structure of Fagus sylvatica in mixed vs. pure European forests Type de document : Article/Communication Auteurs : Ignacio Barbeito, Auteur ; Mathieu Dassot , Auteur ; Dominik Bayer, Auteur ; Catherine Collet, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 381 - 390 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] Allemagne
[Termes IGN] allométrie
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Espagne
[Termes IGN] Fagus sylvatica
[Termes IGN] forêt
[Termes IGN] France (administrative)
[Termes IGN] houppier
[Termes IGN] productivité
[Termes IGN] SuèdeRésumé : (Auteur) Competition with neighboring trees of different species can affect crown size and shape. However, whether intra-specific differences in crown characteristics in mixed stands compared to pure stands are dependent on site conditions remains poorly understood. We used terrestrial laser scanning (TLS) to examine the differences in Fagus sylvatica crown characteristics at four sites, each of which contained pure stands of F. sylvatica and their mixture with Pinus sylvestris. These sites covered the area where the mixture occurs in Europe from south to north, representing a gradient of F. sylvatica productivity, defined as the mean increment of annual volume growth in pure F. sylvatica stands. Despite the large range in productivity, F. sylvatica trees in mixtures had larger crowns regardless of site conditions, with a higher proportion of their crown volume in the lower canopy compared to trees in pure stands. Larger crown volumes were related to higher live crown ratios and greater crown expansion, depending on the site. The magnitude of the mixing effect was variable among the crown characteristics evaluated, but overall our findings provide evidence that for a given species combination and density, the effect of mixture increased in the two most productive sites. TLS-derived novel crown metrics revealed that the mixing effect was affected by productivity, which was not captured by traditionally measured crown variables. Numéro de notice : A2017-880 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2017.09.043 Date de publication en ligne : 02/10/2017 En ligne : https://doi.org/10.1016/j.foreco.2017.09.043 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91159
in Forest ecology and management > vol 405 (1 December 2017) . - pp 381 - 390[article]An examination of diameter density prediction with k-NN and airborne lidar / Jacob L. Strunk in Forests, vol 8 n° 11 (November 2017)
[article]
Titre : An examination of diameter density prediction with k-NN and airborne lidar Type de document : Article/Communication Auteurs : Jacob L. Strunk, Auteur ; Peter J. Gould, Auteur ; Petteri Packalen, Auteur ; Krishna P. Poudel, Auteur ; Hans-Erik Andersen, Auteur ; Hailemariam Temesgen, Auteur Année de publication : 2017 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Caroline du Sud (Etats-Unis)
[Termes IGN] classification barycentrique
[Termes IGN] classification par la distance de Mahalanobis
[Termes IGN] diamètre des arbres
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] lasergrammétrie
[Vedettes matières IGN] Inventaire forestierRésumé : (Auteur) While lidar-based forest inventory methods have been widely demonstrated, performances of methods to predict tree diameters with airborne lidar (lidar) are not well understood. One cause for this is that the performance metrics typically used in studies for prediction of diameters can be difficult to interpret, and may not support comparative inferences between sampling designs and study areas. To help with this problem we propose two indices and use them to evaluate a variety of lidar and k nearest neighbor (k-NN) strategies for prediction of tree diameter distributions. The indices are based on the coefficient of determination (R2), and root mean square deviation (RMSD). Both of the indices are highly interpretable, and the RMSD-based index facilitates comparisons with alternative (non-lidar) inventory strategies, and with projects in other regions. K-NN diameter distribution prediction strategies were examined using auxiliary lidar for 190 training plots distribute across the 800 km2 Savannah River Site in South Carolina, USA. We evaluate the performance of k-NN with respect to distance metrics, number of neighbors, predictor sets, and response sets. K-NN and lidar explained 80% of variability in diameters, and Mahalanobis distance with k = 3 neighbors performed best according to a number of criteria Numéro de notice : A2017-877 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/f8110444 Date de publication en ligne : 16/11/2017 En ligne : https://doi.org/10.3390/f8110444 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91213
in Forests > vol 8 n° 11 (November 2017)[article]
Titre : Assessing the economic value of 3D geo-information Type de document : Rapport Auteurs : Andrew Coote, Auteur ; Phil Knight, Auteur ; Tina Svan Colding, Auteur ; et al., Auteur ; Frédéric Cantat , Auteur Editeur : Dublin : European Spatial Data Research EuroSDR Année de publication : 01/11/2017 Collection : EuroSDR official publication, ISSN 0257-0505 num. 68 Importance : 127 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Information géographique
[Termes IGN] analyse coût-avantage
[Termes IGN] données localisées 3D
[Termes IGN] valeur économiqueIndex. décimale : 37.00 Géomatique - information géographique - infrastructure de données Résumé : (auteur) The use of 3D geo-information has rapidly developed in recent years. Technological advances have driven this evolution and reduced the costs involved in the procurement and processing of 3D geo - information. Consequently, National Mapping Agencies (NMA’s) are actively seeking to transform their data operations and processes to produce such enhanced products. However, budgetary constraints in the public sector necessitate a rigorous assessment of costs and benefits before opportunities can be developed. This report is the culmination of a EuroSDR project that undertook a business case analysis over 12 months in collaboration with 11 European national and regional mapping agencies.
The analysis undertaken was structured around use cases (in order to examine the value derived within specific business contexts) and employed two methodologies: (i) value chain analysis and (ii) cost - benefit analysis to identify the quantification of value add identified by value chain analysis and the assessment of costs.
Value chain analysis identifies the connections between the supply and demand sides of a product or service and qualitatively identifies the value that is added throughout the chain of processes from source to end-user. Cost - benefit analysis facilitates an estimation of Return on Investment (RoI) by quantifying the costs and quantifiable benefits that arise from an investment over a defined period of time.
The project’s stakeholders initially selected six use cases for study: forestry management, flood management, 3D cadastre and valuation, resilience (civil contingency), asset management and urban planning. Over the course of six different workshops value chain analysis was applied to each of these use cases. Out of this process, two use cases were then selected for quantification using cost-benefit analysis: flood management due to the ubiquity of the challenge and its high political profile, and urban planning as 3D geo - information has a significant potential to contribute to the problems of managing urban growth. The process ended with the findings and outcomes being shared and consolidated at a workshop attended by delegates from each stakeholder.
Urban planning cost-benefit analysis - the costs are based on real - world cost estimates from Denmark, scaled up for the Republic of Ireland using the comparative land areas. The benefits are based on the following examples of financial impacts (for urban areas only):
• Local Area Plan (LAP) revision and the impact on the planning authority • Visual impact assessment and the reduced costs for developers
• Reduced time for citizens to make LAP submissions and major scheme objections
• General improvements to public sector efficiency.
Based on a 10 year project life cycle and discount rate of 4%, the results indicate a benefit to cost ratio of 2.1:1 and Net Present Value of € 22 million.
Flood management cost-benefit analysis - the same financial model as was applied to the urban planning case was also used for flood management. However, three approaches were taken to “triangulate” the assessment and to illustrate the use of different methodologies:
Cost Avoidance (Option 1) - this estimates the damages and losses that could have been avoided had 3D geo - information been used rather than the information used currently. The avoided damages are then interpreted as the benefits of using 3D geo - information. It has the advantage of requiring only limited inputs and is based on data available from Switzerland: (i) historical information on the loss and damage from previous events and (ii) interviews 8 with experts to indicate the positive effects of a high accuracy DTM. This resulted in a benefit to cost ratio of 3.3:1 and Net Present Value (after 10 years) of € 8.9 million.
Case Study (Option 2) - this uses case study evidence from the Netherlands on public sector benefits from data sharing and the reduced costs of: (i) land survey work, (ii) failures resulting from earlier detection of design errors and (iii) environmental impact assessment s. This assessment gives a benefit to cost ratio of 3.2:1 and Net Present Value (after 10 years) of € 8.6 million.
Benefits Transfer (Option 3) - this uses information from a comparable study undertaken for USGS study entitled, ‘National Enhanced Elevation Assessment’ [Dewberry 2012]. Belgium has been used to illustrate this approach, although results for other countries involved in the study can also be automatically calculated within the financial model. This assessment method gives a benefit to cost ratio of 5.3:1 and Net Present Value (after 10 years) of € 27 million. The higher return calculated by this approach can be explained as Belgium would be unlikely to achieve the economies of scale of data capture costs in the US. A benefit to cost ratio “write down” of 50% would bring it into line with the returns predicted by the other two approaches.
The cost-benefit analysis demonstrated in both of the selected use cases that benefits outstrip costs by a multiple of between two and three times even when considering each use cases in isolation. As further applications of 3D geo–information are added, additional costs should rise more slowly, whilst benefits should accrue at a similar rate, thereby enhancing the overall rate of return. Investment proposals with the type of return profile found in this study would be expected to be positively received, provided the funds were available from public sources.
Further work using this methodology could usefully be considered in relation to the following use cases:
3D Cadastre and Valuation – in the consultant’s view this represents the best opportunity to complete cost - benefit analysis for one of the remaining use cases for which value chain mapping was undertaken. The timing of ground - breaking work in Denmark may mean that access to their internal economic assessment might now be publicly released making this a relatively quick and easy extension of the study into a potentially very financially attractive application.
Asset management – this should be approached by the creation of value chains for significant subsets of this large and complex use case, particularly transport asset management and streetworks. The recent study in Queensland may provide an opportunity for a cost - effective benefits transfer process to be applied.Note de contenu : 1 INTRODUCTION
2 ECONOMIC CONCEPTS
2.1 The Value of Information
2.2 Methodologies used to assess the value of 3D geo-information in this project
3 APPROACH
3.1 Stages
3.2 Peer Review
3.3 Skill Transfers
4 VALUE CHAIN ANALYSIS RESULTS
4.1 Forest Management
4.2 Flood Management
4.3 3D Cadastre and Valuation
4.4 Resilience (civil contingency)
4.5 Asset Management
4.6 Urban Planning
5 COST-BENEFIT ANALYSIS RESULTS
5.1 Selected Use Cases for Cost-Benefit Analysis
5.2 Urban Planning
5.3 Flood Management
6 CONCLUSIONNuméro de notice : 17508 Affiliation des auteurs : IGN+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Rapport nature-HAL : RappRech DOI : sans En ligne : http://www.eurosdr.net/sites/default/files/uploaded_files/pub68_economicvalue-3d [...] Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90443 Documents numériques
en open access
Assessing the economic value ... - pdf éditeurAdobe Acrobat PDF Fusion of hyperspectral and LiDAR data using sparse and low-rank component analysis / Behnood Rasti in IEEE Transactions on geoscience and remote sensing, vol 55 n° 11 (November 2017)PermalinkMapping the height and spatial cover of features beneath the forest canopy at small-scales using airborne scanning discrete return Lidar / Matthew Sumnall in ISPRS Journal of photogrammetry and remote sensing, vol 133 (November 2017)PermalinkTree species classification using within crown localization of waveform LiDAR attributes / Rosmarie Blomley in ISPRS Journal of photogrammetry and remote sensing, vol 133 (November 2017)PermalinkBayesian graph-cut optimization for wall surfaces reconstruction in indoor environments / Georgios-Tsampikos Michailidis in The Visual Computer, vol 33 n° 10 (October 2017)PermalinkGeolokit: An interactive tool for visualising and exploring geoscientific data in Google Earth / Antoine Triantafyllou in International journal of applied Earth observation and geoinformation, vol 62 (October 2017)PermalinkLearning effectiveness of virtual environments for 3D terrain interpretation and data acquisition / A.M. Perez-Romero in Survey review, vol 49 n° 355 (October 2017)PermalinkMulti-model estimation of understorey shrub, herb and moss cover in temperate forest stands by laser scanner data / Hooman Latifi in Forestry, an international journal of forest research, vol 90 n° 4 (October 2017)PermalinkRegistration of images to Lidar and GIS data without establishing explicit correspondences / Gabor Barsai in Photogrammetric Engineering & Remote Sensing, PERS, vol 83 n° 10 (October 2017)PermalinkSignificant effect of topographic normalization of airborne LiDAR data on the retrieval of plant area index profile in mountainous forests / Jing Liu in ISPRS Journal of photogrammetry and remote sensing, vol 132 (October 2017)PermalinkA structured regularization framework for spatially smoothing semantic labelings of 3D point clouds / Loïc Landrieu in ISPRS Journal of photogrammetry and remote sensing, vol 132 (October 2017)PermalinkDeveloping a wind turbine planning platform: Integration of “sound propagation model–GIS-game engine” triplet / Azarakhsh Rafiee in Environmental Modelling & Software, vol 95 (September 2017)PermalinkEffects of using different sources of remote sensing and geographic information system data on urban stormwater 2D–1D modeling / Yi Hong in Applied sciences, vol 7 n° 9 (September 2017)PermalinkForest canopy height estimation using satellite laser altimetry : a case study in the Western Ghats, India / S.M. Ghosh in Applied geomatics, vol 9 n° 3 (September 2017)PermalinkImpact of spatial correlations on the surface estimation based on terrestrial laser scanning / Tobias Jurek in Journal of applied geodesy, vol 11 n° 3 (September 2017)PermalinkPoint cloud refinement with self-calibration of a mobile multibeam lidar sensor / Houssem Nouira in Photogrammetric record, vol 32 n° 159 (September 2017)PermalinkPrecision estimation of the angular resolution of terrestrial laser scanners / Xijiang Chen in Photogrammetric record, vol 32 n° 159 (September 2017)PermalinkTerrain model reconstruction from terrestrial LiDAR data using radial basis functions / Jules Morel in IEEE Computer graphics and applications, vol 37 n° 5 ([01/09/2017])PermalinkUrban building reconstruction from raw LiDAR point data / Cheng Yi in Computer-Aided Design, vol 9x (2017)PermalinkVisual inspection of fire-damaged concrete based on terrestrial laser scanner data / Wallace Mukupa in Applied geomatics, vol 9 n° 3 (September 2017)Permalink3D local feature BKD to extract road information from mobile laser scanning point clouds / Yang Bisheng in ISPRS Journal of photogrammetry and remote sensing, vol 130 (August 2017)Permalink