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Past and future evolution of French Alpine glaciers in a changing climate: a deep learning glacio-hydrological modelling approach / Jordi Bolibar Navarro (2020)
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Titre : Past and future evolution of French Alpine glaciers in a changing climate: a deep learning glacio-hydrological modelling approach Type de document : Thèse/HDR Auteurs : Jordi Bolibar Navarro, Auteur ; Antoine Rabatel, Auteur ; Isabelle Gouttevin, Auteur ; Eric Sauquet, Auteur Editeur : Grenoble [France] : Université Grenoble Alpes Année de publication : 2020 Importance : 143 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse pour obtenir le grade de Docteur de l'Université Grenoble Alpes, Spécialité : Sciences de la Terre et de l’Univers et de l’EnvironnementLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] Alpes (France)
[Termes IGN] analyse diachronique
[Termes IGN] apprentissage automatique
[Termes IGN] bilan de masse
[Termes IGN] changement climatique
[Termes IGN] glacier
[Termes IGN] modèle de simulation
[Termes IGN] modèle hydrographique
[Termes IGN] modèle numérique de surface
[Termes IGN] réseau neuronal artificielIndex. décimale : THESE Thèses et HDR Résumé : (auteur) The European Alps are among the most affected regions in the world by climate change, displaying some of the strongest glacier retreat rates. Long-term interactions between society, mountain ecosystems and glaciers in the region raise important questions on the future evolution of glaciers and their derived environmental and socioeconomical impacts. In order to correctly assess the regional response of glaciers in the French Alps to climate change, there is a need for adequate modelling tools. In this work, we explore new ways to tackle both glacier evolution and glacio-hydrological modelling at a regional scale. Glacier evolution modelling has traditionally been performed using empirical or physical approaches, which are becoming increasingly challenging to optimize with the ever growing amount of available data. Here, we present, to our knowledge, the first effort ever to apply deep learning (i.e. deep artificial neural networks) to simulate the evolution of glaciers. Since both the climate and glacier systems are highly nonlinear, traditional linear mass balance models offer a limited representation of climate-glacier interactions. We show how important nonlinearities in glacier mass balance are captured by deep learning, substantially improving model performance over linear methods.This novel method was first applied in a study to reconstruct annual mass balance changes for all glaciers in the French Alps for the 1967-2015 period. Using climate reanalyses, topographical data and glacier inventories, we demonstrate how such an approach can be successfully used to reconstruct large-scale mass balance changes from observations. This study also offered new insights on how glaciers evolved in the French Alps during the last half century, confirming the rather neutral observed mass balance rates in the 1980s and displaying a well-marked acceleration in mass loss from the 2000s onwards. Important differences between regions are found, with the Mont-Blanc massif presenting the lowest mass loss and the Chablais being the most affected one. Secondly, we applied this modelling framework to simulate the future evolution of all glaciers in the region under multiple (N=29) climate change scenarios. Our estimates indicate that most ice volume in the region will be lost by the end of the 21st century independently from future climate scenarios. We predict average glacier volume losses of 74%, 80% and 88% under RCP 2.6 (n=3), RCP 4.5 (n=13) and RCP 8.5 (n=13), respectively. By the end of the 21st century the French Alps will be largely ice-free, with glaciers only remaining in the Mont-Blanc and Pelvoux massifs. Note de contenu : Introduction
1- Glaciers
2- Glacierized mountain catchments
3- OutlookNuméro de notice : 28311 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Thèse française Note de thèse : Thèse de Doctorat : Sciences de la Terre et de l’Univers et de l’Environnement : Grenoble : 2020 Organisme de stage : Institut des Géosciences de l’Environnement (Grenoble) DOI : sans En ligne : https://tel.archives-ouvertes.fr/tel-03052063v2/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98202
Titre : Prototype de viewer web 3D intégrant le BIM au SIG Type de document : Mémoire Auteurs : Axel Chassard, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2020 Importance : 57 p. Format : 21 x 30 cm Note générale : Bibliographie
Rapport de projet pluridisciplinaire, cycle ING2Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] analyse des besoins
[Termes IGN] état de l'art
[Termes IGN] intégration de données
[Termes IGN] interface web
[Termes IGN] lutte contre l'incendie
[Termes IGN] modélisation 3D du bâti BIM
[Termes IGN] prototype
[Termes IGN] quartier
[Termes IGN] SIG 3DIndex. décimale : PROJET Mémoires : Rapports de projet - stage des ingénieurs de 2e année Résumé : (Auteur) Ce document présente les travaux que j’ai réalisé lors de mon stage pluridisciplinaire dans l’entreprise Sword. Ce stage s’inscrit dans une thématique de recherche et développement sur l’intégration du BIM dans un SIG 3D. Après avoir identifié des cas d’usage et réalisé un état de l’art technologique, j’ai analysé et réalisé la partie interface graphique d’un prototype de viewer 3D facilitant le contrôle des équipements de défenses incendies à l’échelle d’un quartier. Note de contenu :
Introduction
1. Contexte du sujet
1.1 L’entreprise Sword
1.2 Les objectifs du stage
1.3 Réflexion sur les cas d’usages et définition d’un projet d’application
2. Organisation du stage
2.1 Cadre de travail
2.2 Organisation du travail
2.3 Spécificité de mon travail
3. Analyse
3.1 Analyse du besoin
3.2 Étude technique
4. Résultats et perspectives
4.1 Résultats du projet
4.2 Perspectives
4.3 Retour d’expérience sur les technologies utilisées
ConclusionNuméro de notice : 26365 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Mémoire de projet pluridisciplinaire Organisme de stage : SWORD SAS Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95807 Documents numériques
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Prototype de viewer web 3D intégrant le BIM au SIG - pdf auteurAdobe Acrobat PDFRealistic modeling of power transmission lines with geographic information systems / Joram Schito (2020)
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Titre : Realistic modeling of power transmission lines with geographic information systems Type de document : Thèse/HDR Auteurs : Joram Schito, Auteur Editeur : Zurich : Eidgenossische Technische Hochschule ETH - Ecole Polytechnique Fédérale de Zurich EPFZ Année de publication : 2020 Importance : 266 p. Format : 21 x 30 cm Note générale : bibliographie
A dissertation submitted to attain the degree of Doctor of Sciences of ETH ZurichLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] analyse multicritère
[Termes IGN] ligne électrique
[Termes IGN] outil d'aide à la décision
[Termes IGN] programmation par contraintes
[Termes IGN] recherche du chemin optimal, algorithme de
[Termes IGN] réseau électrique
[Termes IGN] réseau technique souterrain
[Termes IGN] SIG 3DRésumé : (auteur) Since renewable energy sources are in increasing demand due to the energy transition, the planning of new (Power) Transmission Line (TL) is becoming more and more important. Conflicting interests between stakeholders, the legislation and different transmission technologies turn TL planning into a complex spatial decision problem, however. Therefore, a Spatial Decision Support System (SDSS) which combines Multi-Criteria Decision Analysis (MCDA) techniques with methods provided by Geographic Information Systems (GIS) can support decision-makers in finding an optimal Transmission Line Path (TLP) that suits different interests. Existing SDSS, however, are constrained to either overhead lines or earth cables, while no computational solution has been found so far, for how they can be combined with each other. Furthermore, the methods prevailingly used come with some conceptual issues that affect realistic TL planning. Therefore, we investigated several methods for making GIS-based TL planning more realistic, developing two approaches that are the first of their kind to identify an optimal corridor for a combined line (CL), based on two different decision models. Both approaches were included in a 3D Decision Support System (3D DSS), which consists of various algorithms for determining optimal TL corridors and paths on different voltage levels, regardless of the transmission technology. A user study conducted with nine experts revealed that the procedural approach was most supported and represented stakeholders’ interests most reliably when identifying optimal CLs. Our results provide evidence that the 3D DSS facilitates the planning of new TLs, fosters the profound analysis of different alternatives, and supports stakeholders when discussing the benefits and weaknesses of different TLP alternatives. Since experts have high confidence in benefiting from a computer-based semi-automated approach, SDSS will play an increasingly important role in future TL planning. Numéro de notice : 17654 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Thèse étrangère Note de thèse : Doctoral thesis : Sciences : ETH Zurich : 2020 En ligne : http://dx.doi.org/10.3929/ethz-b-000454195 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97912
Titre : Remotely sensing the species of individual trees Type de document : Thèse/HDR Auteurs : Yifang Shi, Auteur ; Andrew K. Skidmore, Directeur de thèse ; Tiejun Wang, Directeur de thèse Editeur : Enschede [Pays Bas] : University of Twente Année de publication : 2020 Collection : ITC Dissertation num. 376 Importance : 163 p. Format : 21 x 30 cm Note générale : bibliographie
Doctor of Philosophy, Faculty of Geo-Information Science and Earth Observation, University of TwenteLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Abies alba
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] Bavière (Allemagne)
[Termes IGN] chlorophylle
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] forêt tempérée
[Termes IGN] image hyperspectrale
[Termes IGN] image infrarouge couleur
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Leaf Mass per Area
[Termes IGN] orthoimageRésumé : (auteur) The accurate identification of tree species is critical for the management of forest ecosystems. Mapping of tree species is an important task as it can assist a wide range of environmental applications, such as biodiversity monitoring, ecosystem services assessment, invasive species detection, and sustainable forest management. Compared to the conventional approaches based on labor-intensive field measurements, remote sensing has supplied a large variety of cutting-edge techniques to accomplish forest inventory. However, individual tree species classification in natural mixed forests, as it is typical in central Europe, is still a challenging task. High spectral and structural intra-species variability and inter-species similarity, due to phenological effects, differences in tree age and openness of canopies, shadowing effects, and environment variability, restrict tree species separability. An in-depth understanding of the relationship between species-specific features and remote sensing observations for tree species classification needs further investigation. This thesis aimed to accurately map the species of individual trees using multi-source remotely sensed data, including aerial photographs, airborne LiDAR and hyperspectral data. The research in the thesis firstly evaluated the performance of geometric and radiometric metrics from airborne LiDAR data under leaf-on and leaf-off conditions for individual tree species discrimination. The results empathized the importance of intensity-related LiDAR metrics for tree species identification under both leaf-on and leaf-off conditions. Then, the thesis examined whether multi-temporal digital CIR orthophotos could be used to further increase the accuracy of airborne LiDAR-based individual tree species mapping. The results showed that the texture features generated from multi-temporal digital CIR orthophotos under different view-illumination conditions are species-specific. Combining these texture features with LiDAR metrics significantly improved the accuracy of individual tree species mapping. To explore more valuable species-specific features, the thesis consequently integrated three plant functional traits (i.e. equivalent water thickness, leaf mass per area and leaf chlorophyll) retrieved from hyperspectral data with hyperspectral derived spectral features and airborne LiDAR derived metrics for mapping five tree species. Three selected plant functional traits were accurately retrieved using radiative transfer model and further improved the accuracy of tree species classification. Eventually, the thesis focused on an important tree species silver fir, and accurately mapped individuals of this species based on one-class classifiers using integrated airborne hyperspectral and LiDAR data. The mapping results provided the references locating the areas with a high occurrence probability of silver fir trees and hence increase the efficiency in subsequent field campaigns for forest management and biodiversity monitoring. This thesis explored the potential of various remotely sensed datasets for individual tree species mapping. The methodologies and findings in this thesis can be applied in the mapping of other tree species, which enriches the knowledge of species-specific characteristics and related remotely sensed signatures. The emerging of UAVs and the upcoming hyperspectral missions such as EnMAP and HySPIRI deliver valuable datasets with multi-scale coverage and revisit observations, which can be used for mapping the diversity of tree species at stand or regional level. Note de contenu : - General introduction
- Important LiDAR metrics for discriminating tree species
- Improving LiDAR-based tree species mapping using multi-temporal CIR orthophotos
- Tree species classification using remotely sensed plant functional traits
- Mapping individual silver fir trees in a Norway spruce dominated forest
- Synthesis: Mapping individual tree species using multi-source remotely sensed dataNuméro de notice : 17671 Affiliation des auteurs : non IGN Thématique : FORET Nature : Thèse étrangère Note de thèse : PhD thesis : : University of Twente : 2020 DOI : 10.3990/1.978903654953-0 Date de publication en ligne : 31/01/2020 En ligne : https://doi.org/10.3990/1.978903654953-0 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97985 Robust deformation monitoring of bridge structures using MEMS accelerometers and image-assisted total stations / Mohammad Omidalizarandi (2020)
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Titre : Robust deformation monitoring of bridge structures using MEMS accelerometers and image-assisted total stations Type de document : Thèse/HDR Auteurs : Mohammad Omidalizarandi, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2020 Collection : DGK - C, ISSN 0065-5325 num. 859 Importance : 260 p. Format : 21 x 30 cm Note générale : bibliographie
Diese Arbeit ist gleichzeitig veröffentlicht in: Wissenschaftliche Arbeiten der Fachrichtung Geodäsie und Geoinformatik der Universität Hannover, ISSN 0174-1454, Nr. 366Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] accéléromètre
[Termes IGN] algorithme espérance-maximisation
[Termes IGN] auscultation d'ouvrage
[Termes IGN] méthode robuste
[Termes IGN] microsystème électromécanique
[Termes IGN] pont
[Termes IGN] surveillance d'ouvrage
[Termes IGN] tachéomètre électronique
[Termes IGN] topométrie de précisionRésumé : (auteur) Today, short- and long-term structural health monitoring (SHM) of bridge structures has received considerable attention. However, permanent, cost-effective, and reliable monitoring are still challenging issues. From a surveying or civil engineer's point of view, vibration-based SHM is often carried out by inspecting the changes in the dynamic responses of bridge structures known as modal parameters, such as eigen frequencies, eigenforms and modal damping. The use of cost-effective micro-electro-mechanical-systems (MEMS) accelerometers with a high sampling frequency is becoming more affordable and feasible for the aforementioned monitoring task. Within this dissertation, a three-step scenario is proposed to choose a suitable MEMS accelerometer despite of its purchase price, measurement range and sampling frequency. Firstly, a robust calibration procedure is proposed and implemented to model MEMS related systematic errors such as biases, scale factors, and non-orthogonality angles between the axes. Secondly, a controlled excitation experiment is conducted by using a high-precision shaker. Thirdly, a statictest experiment is accomplished over a long period. Robust, accurate, and automatic estimation of the modal parameters is particularly challenging when vibration measurements are contaminated with a high coloured measurement noise, e.g., due to cost-effective MEMS acceleration data. This is even more challenging when the structure is continuously under imposed forces due to moving vehicles or wind. For this purpose, a robust and automatic vibration analysis procedure the so–called robust time domain modal parameter identification (RT-MPI) approach is proposed and implemented. It is a novel approach in the sense of automatic excitation (e.g. ambient) window selection, automatic and reliable identification of initial eigen frequencies even closely spaced ones as well as robustly and accurately estimating the modal parameters. To estimate frequencies, damping ratio coefficients, amplitudes, and phase shifts, an observation model consisting of a damped harmonic oscillation (DHO) model, an autoregressive model of coloured measurement noise and a stochastic model in the form of the heavy-tailed family of scaled t-distributions with unknown degree of freedom and scale factor, is employed. The aforementioned three parametric models are jointly adjusted by means of a generalised expectation maximisation (GEM) algorithm. The proposed RT-MPI algorithm is also able to estimate amplitudes in a metric unit and with a high accuracy for the recorded acceleration data by means of double integration of the DHO model. The eigenforms are characterised in a subsequent step, and by using the estimated parameters from the GEM algorithm. In addition, having amplitudes in the metric unit allows to characterise deflection eigen forms in their true scales for selected excitation windows within short time intervals. The deformation/displacement monitoring by merely using the MEMS accelerometer is challenging, since it suffers from accuracy degradation with time for absolute position/displacement estimates. Therefore, the MEMS accelerometers and an image-assisted total station (IATS) are fused by performing one-dimensional (1D) coordinate update within the Kalman filtering framework. To generate 1D displacement data from the IATS, video frames of a passive target, that is attached to a bridge structure, are captured by means of a telescope camera of the IATS. A passive target centroid detection algorithm is proposed and implemented, which is robust and reliable with respect to poor environmental conditions, such as low lighting, dusty situations, and skewed angle targets. Next, an angular conversion factor of the telescope camera is calibrated, which allows to convert the generated displacement data from pixel to metric unit.
Experiments are performed in four case studies including simulation, controlled excitation and two real applications of a footbridge structure and a synthetic bridge. The estimated modal parameters are compared and validated by their true values as well as their corresponding estimates obtained from reference sensors such as reference accelerometer, geophone, and laser tracker. Additionally, the estimated eigen frequencies and damping ratio coefficients are compared with a well-known covariance driven stochastic subspace identification (SSI-COV) approach. The results show that the MEMS accelerometers are suitable for identifying all occurring eigen frequencies of the bridge structures. Moreover, the vibration analysis procedure demonstrates that amplitudes are estimated in submillimetre range accuracy, frequencies with an accuracy of better than 0.1 Hz and damping ratio coefficients with an accuracy of better than 0.1 and 0.2%for modal and system damping, respectively. The analysis reveals the superiority of the proposed RT-MPI algorithm compared to the SSI-COV algorithm. Finally, a high accurate displacement time series at the level of submillimetre is generated by fusion of the IATS and the MEMS measurements.Numéro de notice : 17680 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère En ligne : https://dgk.badw.de/fileadmin/user_upload/Files/DGK/docs/c-859.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98021 Robust pose estimation and calibration of catadioptric cameras with spherical mirrors / Sagi Filin in Photogrammetric Engineering & Remote Sensing, PERS, vol 86 n° 1 (January 2020)
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PermalinkTrajectoires paysagères des cônes de déjection torrentiels des Alpes du nord (Maurienne et Tarentaise) / Thérèse Hugerot (2020)
PermalinkFaut-il des relevés de flore exhaustifs pour caractériser et cartographier l'acidité et les propriétés nutritionnelles des sols ? / Paulina E. Pinto in Rendez-vous techniques, n° 61-62 (hiver - printemps 2019)
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PermalinkNovel adaptive histogram trend similarity approach for land cover change detection by using bitemporal very-high-resolution remote sensing images / Zhi Yong Lv in IEEE Transactions on geoscience and remote sensing, vol 57 n° 12 (December 2019)
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PermalinkRobust acquisition at GPS receivers in unsafe locations using complex wavelet transform / M. Moazedi in Survey review, vol 51 n° 369 (November 2019)
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