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Dissertations / Theses on the topic 'Inversion methods'

Author: Grafiati

Published: 10 March 2023

Last updated: 31 July 2025

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1

DENICH, ELEONORA. "Numerical methods for electromagnetic inversion." Doctoral thesis, Università degli Studi di Trieste, 2023. https://hdl.handle.net/11368/3042164.

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The aim of electromagnetic (EM) sounding methods in geophysics is to obtain information about the subsurface of the earth by recorded measurements taken at the surface. In particular, the goal is to determine variations in the electrical conductivity of the earth with depth by employing an inversion procedure. In this work we focus on one technique, that consists of placing a magnetic dipole above the surface, composed of a transmitter coil and different couples of adjacent receiver coils. The receiver couples are placed at different distances (offsets) from the transmitter coil. In this setti

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2

Kamm, Jochen. "Inversion and Joint Inversion of Electromagnetic and Potential Field Data." Doctoral thesis, Uppsala universitet, Geofysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-215673.

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In this thesis, four inversion problems of different scale and difficulty are solved. Two of them are electromagnetic inverse problems. Two more are joint inversion problems of potential field data and other types of data. First, a linear approximation, which is a generalization of the low-induction-number approximation standard in slingram dual-loop interpretation is developed and used for rapid two and three dimensional inversion. The approximation takes induction within a background half-space into account and can thus be applied in conductive scenarios, where otherwise a rigorous electroma

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3

Saunders, Jonathan Howard. "Electrical inversion and characterisation methods in geophysics." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413721.

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4

MACIEL, Jonathas da Silva. "Structural constraints for image-based inversion methods." Universidade Federal do Pará, 2016. http://repositorio.ufpa.br/jspui/handle/2011/9021.

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Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-07-26T14:09:55Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_StructuralconstraintsImage.pdf: 21057747 bytes, checksum: c218ce93af99d33375ec25eeec4aa33e (MD5)<br>Approved for entry into archive by Irvana Coutinho (irvana@ufpa.br) on 2017-08-23T13:21:47Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_StructuralconstraintsImage.pdf: 21057747 bytes, checksum: c218ce93af99d33375ec25eeec4aa33e (MD5)<br>Made available in

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5

Walker, Matthew James. "Methods for Bayesian inversion of seismic data." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/10504.

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The purpose of Bayesian seismic inversion is to combine information derived from seismic data and prior geological knowledge to determine a posterior probability distribution over parameters describing the elastic and geological properties of the subsurface. Typically the subsurface is modelled by a cellular grid model containing thousands or millions of cells within which these parameters are to be determined. Thus such inversions are computationally expensive due to the size of the parameter space (being proportional to the number of grid cells) over which the posterior is to be determined.

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6

Vu, Tuan-Anh. "One-shot inversion methods and domain decomposition." Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAE009.

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Notre objectif principal est d’analyser la convergence d’une méthode d’optimisation basée sur le gradient, pour résoudre des problèmes inverses d’identification de paramètres, dans laquelle les problèmes directs et adjoints correspondants sont résolus par un solveur itératif. Le couplage des itérations pour les trois inconnues (le paramètre du problème inverse, la solution du problème direct et la solution du problème adjoint) donne ce que l’on appelle les méthodes d’inversion de type one-shot. De nombreux tests numériques ont montré que l’utilisation de très peu d’itérations internes pour les

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7

Li, Song. "Numerical methods for stable inversion of nonlinear systems." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/15028.

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8

Wilson, Adam. "Theory and methods of frequency-dependent AVO Inversion." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4740.

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Amplitude-versus-offset, AVO, approximations allow the estimation of various properties from pre-stack seismic gathers. Recently it has been suggested that fluid mobility is a controlling factor in pore pressure equalisation and can result in anomalous velocity dispersion in the seismic bandwidth. However, current approximations all assume an elastic subsurface and are unable to account for velocity dispersion. I have applied existing methodologies to a real dataset to qualitatively detect and interpret spectral amplitude anomalies. Three areas had AVO and spectral signature consistent with fr

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9

Sawyer, Nicolas B. E. "Novel optical surface metrology methods." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287239.

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10

Thurin, Julien. "Uncertainties estimation in Full Waveform Inversion using Ensemble methods." Thesis, Université Grenoble Alpes, 2020. https://tel.archives-ouvertes.fr/tel-02570602.

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L'inversion de forme d'onde complète (FWI) est une méthode d'inversion non-linéaire qui a pour but l'obtention de modèles précis des propriétés physiques du sous-sol terrestre. Ces modèles, véritables cartes de propriétés physiques, sont indispensables pour l'exploration et l'étude des structures internes de la Terre.Généralement formulée sous la forme d'un schéma d'optimisation par la méthode des moindres carrés, la FWI compare des enregistrements sismiques observés en surface, avec des données synthétiques calculées à partir d'un modèle numérique de sous-sol. Alors qu'une infinité de modèles

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11

Kim, Junkyoung. "Complex seismic sources and time-dependent moment tensor inversion." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184841.

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There are many examples of earthquakes whose surface expressions are much more complicated than the seismologically derived faulting models. Seismologists also have found seismic source complexity and improved seismicity data have shown that rupture may occur on irregular or multiple shear surfaces. To simultaneously map both geometrical and temporal variation of the seismic sources for a complex rupture history from observed seismograms, it is possible to use a time dependent moment tensor (TDMT) inversion. The TDMT inversion algorithm has been tested with three synthetic data examples with v

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12

Michelen, Strofer Carlos Alejandro. "Machine Learning and Field Inversion approaches to Data-Driven Turbulence Modeling." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/103155.

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There still is a practical need for improved closure models for the Reynolds-averaged Navier-Stokes (RANS) equations. This dissertation explores two different approaches for using experimental data to provide improved closure for the Reynolds stress tensor field. The first approach uses machine learning to learn a general closure model from data. A novel framework is developed to train deep neural networks using experimental velocity and pressure measurements. The sensitivity of the RANS equations to the Reynolds stress, required for gradient-based training, is obtained by means of both variat

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13

Pugh, David James. "Bayesian source inversion of microseismic events." Thesis, University of Cambridge, 2016. https://www.repository.cam.ac.uk/handle/1810/253751.

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Rapid stress release at the source of an earthquake produces seismic waves. Observations of the particle motions from such waves are used in source inversion to characterise the dynamic behaviour of the source and to help in understanding the driving processes. Earthquakes either occur naturally, such as in volcanic eruptions and natural geothermal fields, or are linked to anthropogenic activities including hydrofracture of gas and oil reservoirs, mining events and extraction of geothermal fluids. Source inversion is very sensitive to uncertainties in both the model and the data, especially fo

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14

Hicks, Graham John. "Seismic velocities from reflection waveforms : the application of Newton inversion methods." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325127.

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15

Yang, Di Ph D. Massachusetts Institute of Technology. "Full wavefield inversion methods for monitoring time-lapse subsurface velocity changes." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/95558.

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Thesis: Ph. D. in Geophysics, Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2014.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 243-252).<br>Quantitative measurements of seismic velocity changes from time-lapse seismic experiments provide dynamic information about the subsurface that improves the understanding of the geology and reservoir properties. In this thesis, we propose to achieve the quantitative analysis using full wavefield inversion methods which are robust in complex geology. We developed se

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16

Virtanen, I. (Ilkka). "Multi-purpose methods for ionospheric radar measurements." Doctoral thesis, Oulun yliopisto, 2009. http://urn.fi/urn:isbn:9789514292842.

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Abstract From the very beginning of modern ionospheric science, different radar applications have been utilised in ionospheric measurements. The most sophisticated ionospheric radars are the incoherent scatter radars, which detect the extremely weak scattering of radio waves from thermal fluctuations in the ionospheric plasma. Besides the low signal level, the stochastic nature of the scattering process causes further complications to the measurements. The scattering produces a zero-mean random signal, whose autocorrelation function contains the information of the ionospheric plasma parameter

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17

POONDRU, SHIRDISH. "A NEW DIRECT MATRIX INVERSION METHOD FOR ECONOMICAL AND MEMORY EFFICIENT NUMERICAL SOLUTIONS." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1060976742.

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18

Seyfried, Ruben [Verfasser]. "Summability Methods for the Inversion of the Spherical Mean Operator / Ruben Seyfried." Aachen : Shaker, 2014. http://d-nb.info/1059344386/34.

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19

Jokinen, J. (Jarkko). "Uncertainty analysis and inversion of geothermal conductive models using random simulation methods." Doctoral thesis, University of Oulu, 2000. http://urn.fi/urn:isbn:9514255909.

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Abstract Knowledge of the thermal conditions in the lithosphere is based on theoretical models of heat transfer constrained by geological and geophysical data. The present dissertation focuses on the uncertainties of calculated temperature and heat flow density results and on how they depend on the uncertainties of thermal properties of rocks, as well as on the relevant boundary conditions. Due to the high number of involved variables of typical models, the random simulation technique was chosen as the applied tool in the analysis. Further, the random simulation technique was applied in invers

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20

Sievert, Thomas. "GNSS Radio Occultation Inversion Methods and Reflection Observations in the Lower Troposphere." Licentiate thesis, Blekinge Tekniska Högskola, Institutionen för matematik och naturvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17484.

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GNSS Radio Occultation (GNSS-RO) is an opportunistic Earth sensing technique where GNSS signals passing through the atmosphere are received in low Earth orbit and processed to extract meteorological parameters. As signals are received along an orbit, the measured Doppler shift is transformed to a bending angle profile (commonly referred to as bending angle retrieval), which, in turn, is inverted to a refractivity profile. Thanks to its high vertical resolution and SI traceability, GNSS-RO is an important complement to other Earth sensing endeavors. In the lower troposphere, GNSS-RO measurement

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21

Berkel, Paula. "Multiscale methods for the combined inversion of normal mode and gravity variations." Aachen Shaker, 2009. http://d-nb.info/997085304/04.

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22

Gower, Robert Mansel. "Sketch and project : randomized iterative methods for linear systems and inverting matrices." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20989.

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Probabilistic ideas and tools have recently begun to permeate into several fields where they had traditionally not played a major role, including fields such as numerical linear algebra and optimization. One of the key ways in which these ideas influence these fields is via the development and analysis of randomized algorithms for solving standard and new problems of these fields. Such methods are typically easier to analyze, and often lead to faster and/or more scalable and versatile methods in practice. This thesis explores the design and analysis of new randomized iterative methods for solv

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23

Downs, M. L. N. "Mobius inversion of some classical groups and their application to the enumeration of regular hypermaps." Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381232.

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24

Berkel, Paula [Verfasser]. "Multiscale Methods for the Combined Inversion of Normal Mode and Gravity Variations / Paula Berkel." Aachen : Shaker, 2009. http://d-nb.info/1159835357/34.

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25

Prieto, Moreno Kernel Enrique. "Novel mathematical techniques for structural inversion and image reconstruction in medical imaging governed by a transport equation." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/novel-mathematical-techniques-for-structural-inversion-and-image-reconstruction-in-medical-imaging-governed-by-a-transport-equation(b45f5566-daa7-4d47-a982-cf479e360c6f).html.

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Since the inverse problem in Diffusive Optical Tomography (DOT) is nonlinear and severely ill-posed, only low resolution reconstructions are feasible when noise is added to the data nowadays. The purpose of this thesis is to improve image reconstruction in DOT of the main optical properties of tissues with some novel mathematical methods. We have used the Landweber (L) method, the Landweber-Kaczmarz (LK) method and its improved Loping-Landweber-Kaczmarz (L-LK) method combined with sparsity or with total variation regularizations for single and simultaneous image reconstructions of the absorpti

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26

Jiang, Zixian. "Some inversion methods applied to non-destructive testings of steam generator via eddy current probe." Palaiseau, Ecole polytechnique, 2014. http://pastel.archives-ouvertes.fr/docs/00/94/36/13/PDF/Thesis.pdf.

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L'objectif principal de cette thèse est de proposer et de tester quelques méthodes de l'optimisation de forme afin d'identifier et de reconstruire des dépôts qui couvrent la paroi extérieure d'un tube conducteur dans un générateur de vapeurs en utilisant des signaux courant de Foucault. Ce problème est motivé par des applications industrielles en contrôle non-destructive dans le secteur de l'énergie nucléaire. En fait, des dépôts peuvent obstruer le passage de circuit de refroidissement entre les tubes et les plaques entretoises qui les soutiennent, ce qui entraînerait une baisse de productivi

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27

Günther, Thomas. "Inversion methods and resolution analysis for the 2D/3D reconstruction of resistivity structures from DC measurements." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola&quot, 2009. http://nbn-resolving.de/urn:nbn:de:swb:105-4152277.

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The presented thesis deals with the multi-dimensional reconstruction of the earth's conductivity distribution based on DC resistivity data. This task represents a nonlinear and ill-posed minimization problem with many degrees of freedom. In this work, techniques for regularization and controlling of this problem are depicted and classified. Particularly, it is concentrated on explicit regularization types, which impose constraints onto the model. The system of equations as resulting from the application of the Gauss-Newton minimization can be solved efficiently. Furthermore, it is shown how th

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28

Blick, Christian [Verfasser]. "Multiscale Potential Methods in Geothermal Research: Decorrelation Reflected Post-Processing and Locally Based Inversion / Christian Blick." München : Verlag Dr. Hut, 2015. http://d-nb.info/1080754636/34.

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29

Sheffer, Megan Rae. "Forward modelling and inversion of streaming potential for the interpretation of hydraulic conditions from self-potential data." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/235.

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The self-potential method responds to the electrokinetic phenomenon of streaming potential and has been applied in hydrogeologic and engineering investigations to aid in the evaluation of subsurface hydraulic conditions. Of specific interest is the application of the method to embankment dam seepage monitoring and detection. This demands a quantitative interpretation of seepage conditions from the geophysical data. To enable the study of variably saturated flow problems of complicated geometry, a three-dimensional finite volume algorithm is developed to evaluate the self-potential distributio

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30

ARDUINO, ALESSANDRO. "Mathematical methods for magnetic resonance based electric properties tomography." Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2698325.

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Magnetic resonance-based electric properties tomography (MREPT) is a recent quantitative imaging technique that could provide useful additional information to the results of magnetic resonance imaging (MRI) examinations. Precisely, MREPT is a collective name that gathers all the techniques that elaborate the radiofrequency (RF) magnetic field B1 generated and measured by a MRI scanner in order to map the electric properties inside a human body. The range of uses of MREPT in clinical oncology, patient-specific treatment planning and MRI safety motivates the increasing scientific interest in its

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31

Rojas, Jose G. "Geoacoustic inversion using direct methods of ambient noise and explosive acoustic data in a shallow water waveguide." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA343684.

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32

Ernesti, Johannes [Verfasser], and C. [Akademischer Betreuer] Wieners. "Space-Time Methods for Acoustic Waves with Applications to Full Waveform Inversion / Johannes Ernesti ; Betreuer: C. Wieners." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1160303525/34.

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33

Guan, Borui. "Characterization of building materials by electromagnetic non-destructive methods : application to limestone." Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4003/document.

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Le tuffeau est un matériau de construction calcaire largement utilisé dans la vallée de la Loire pour les bâtiments historiques. Le temps passant, il est confronté à des problèmes de pathologies, principalement liées à sa teneur en eau. Pour évaluer cet indicateur, le radar à sauts de fréquence (SFR) a été retenu parmi les techniques d’évaluation non destructives. Cette dernière peut être associée à une technique d’inversion « forme d’onde » dans le domaine fréquentiel (FWFI), technique performante pour obtenir la permittivité, directement en lien avec la teneur en eau. L’inversion FWFI d’un s

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34

Cárdenas, Chapellín Julio José. "Inversion of geophysical data by deep learning." Electronic Thesis or Diss., Sorbonne université, 2022. http://www.theses.fr/2022SORUS185.

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Cette thèse présente la caractérisation d’anomalies magnétiques par des réseaux de neurones convolutifs, et l’application d’outils de visualisation pour comprendre et valider leurs prédictions. L’approche développée permet la localisation de dipôles magnétiques, incluant le comptage dunombre de dipôles, leur position géographique, et la prédiction de leurs paramètres (moment magnétique, profondeur, et déclinaison). Nos résultats suggèrent que la combinaison de deux modèles d’apprentissage profond, "YOLO" et "DenseNet", est la plus performante pour atteindre nos objectifs de classification et d

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Cazenave, Quitterie. "Development and evaluation of multisensor methods for EarthCare mission based on A-Train and airborne measurements." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLV020/document.

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L'impact des nuages de glace sur le cycle de l'eau et le bilan radiatif est encore incertain en raison de la complexité des processus nuageux qui rend difficile l'acquisition d'observations adéquates sur les propriétés des nuages de glace et leur représentation dans les modèles de circulation générale. Les instruments de télédétection actifs et passifs, tels que les radiomètres, les radars et les lidars, sont couramment utilisés pour les étudier. La restitution des propriétés microphysiques des nuages (extinction, contenu en glace, rayon effectif, ...) peut être effectuée à partir d'un seul in

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36

Christodoulou, Apostolos A. "Etude sismotectonique et inversion tridimensionnelle en Grèce du Nord." Grenoble 1, 1986. http://www.theses.fr/1986GRE10086.

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Première Partie: Etude sismotectonique d'un graben complexe, exemple: le graben Mygdonien (Grèce du Nord). Durant les printemps de 1984 et 1985 nous avons installé un réseau sismologique de 29 stations portables dans la région du graben Mydgonien près de Thessaloniki. La sismicité et les mécanismes au foyer ont montré une structure complexe. Des phénomènes compressifs ont été observés au centre du graben. Nous proposons un modèle pour la formation et l'évolution du graben. Au départ la déformation a lieu le long des failles pré-existantes de direction NW-SE ou NNE-SSW avec des mouvements norma

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Chanet, Alain. "Determination de vitesses sismiques entre puits, inversion des temps de parcours par modelisation iterative." Paris 6, 1988. http://www.theses.fr/1988PA066134.

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La tomographie appliquee a la geologie presentee dans ce travail repose sur l'estimation d'une grille de repartition des vitesses sismiques entre puits. Cette estimation est faite a partir des temps de parcours d'ondes sismiques traversant la zone a explorer, elle est effectuee suivant un processus iteratif. Ce processus se presente sous deux aspects : - resolution du probleme direct correspondant aux calculs de temps de parcours theoriques en fonction d'une repartition donnee de vitesses de propagation. - resolution du probleme inverse qui consite a fixer un schema de repartition des vitesses

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Tan, Xihe [Verfasser], Julia [Akademischer Betreuer] Kowalski, and Andreas [Akademischer Betreuer] Kemna. "Development of electromagnetic induction measurement and inversion methods for soil electrical conductivity investigations / Xihe Tan ; Julia Kowalski, Andreas Kemna." Aachen : Universitätsbibliothek der RWTH Aachen, 2020. http://d-nb.info/1238602371/34.

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Indratno, Sapto Wahyu. "Numerical methods for solving linear ill-posed problems." Diss., Kansas State University, 2011. http://hdl.handle.net/2097/8109.

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Doctor of Philosophy<br>Department of Mathematics<br>Alexander G. Ramm<br>A new method, the Dynamical Systems Method (DSM), justified recently, is applied to solving ill-conditioned linear algebraic system (ICLAS). The DSM gives a new approach to solving a wide class of ill-posed problems. In Chapter 1 a new iterative scheme for solving ICLAS is proposed. This iterative scheme is based on the DSM solution. An a posteriori stopping rules for the proposed method is justified. We also gives an a posteriori stopping rule for a modified iterative scheme developed in A.G.Ramm, JMAA,330 (2007

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40

Srivastava, Deepansh. "NMR methods and analysis for determining correlated structural distributions in amorphous solids." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531928644070636.

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41

Chibawara, Trust. "Pricing and hedging asian options using Monte Carlo and integral transform techniques." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4292.

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Thesis (MSc (Mathematics))--University of Stellenbosch, 2010.<br>ENGLISH ABSTRACT: In this thesis, we discuss and apply the Monte Carlo and integral transform methods in pricing options. These methods have proved to be very e ective in the valuation of options especially when acceleration techniques are introduced. By rst pricing European call options we have motivated the use of these methods in pricing arithmetic Asian options which have proved to be di cult to price and hedge under the Black􀀀Scholes framework. The arithmetic average of the prices in this framework, is a sum of correla

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Wittke, Jan [Verfasser], Bülent [Gutachter] Tezkan, Klaus [Gutachter] Spitzer, and Becken [Gutachter] Michael. "Meshless methods for Maxwell’s equations with applications to magnetotelluric modelling and inversion / Jan Wittke ; Gutachter: Bülent Tezkan, Klaus Spitzer, Becken Michael." Köln : Universitäts- und Stadtbibliothek Köln, 2017. http://d-nb.info/1148623698/34.

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Han, Chao. "Advanced signal and imaging methods in ultrasound cortical bone assessment." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS144.

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La technologie à ultrasons constitue un moyen abordable de mettre en œuvre des solutions non invasives pour évaluer de manière diagnostique les caractéristiques mécaniques de l'os. Dans cette thèse nous introduisons la poursuite orthogonale (OMP) pour obtenir une reconstruction robuste de la forme d'onde de chaque écho après rebond sur les faces externe et interne de l'os cortical. Le temps de vol et les fréquences centrales des échos sont utilisés pour calculer l'atténuation normalisée à large bande (nBUA). Des mesure in vivo ont été effectuées avec succès en mode écho et des données de référ

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Galiana, Blanch Savitri. "Two-dimensional modeling and inversion of the controlled-source electromagnetic and magnetotelluric methods using finite elements and full-space PDE-constrained optimization strategies." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/400616.

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The controlled-source electromagnetics (CSEM) and magnetotellurics (MT) methods are common geophysical tools for imaging the Earth's electrical interior. To appreciate measured data, both methods require forward and inverse modeling of the subsurface with the ultimate goal of finding a feasible model for which the simulated data reasonably fits the observations. The goodness of this fit depends on the error in the measured data, on the numerical error and on the degree of approximation inferred by numerical modeling. Therefore, active research focuses on new methods for modeling and inversion

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Line, Michael R., Kevin B. Stevenson, Jacob Bean, et al. "NO THERMAL INVERSION AND A SOLAR WATER ABUNDANCE FOR THE HOT JUPITER HD 209458B FROM HST /WFC3 SPECTROSCOPY." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622434.

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The nature of the thermal structure of hot Jupiter atmospheres is one of the key questions raised by the characterization of transiting exoplanets over the past decade. There have been claims that many hot Jupiters exhibit atmospheric thermal inversions. However, these claims have been based on broadband photometry rather than the unambiguous identification of emission features with spectroscopy, and the chemical species that could cause the thermal inversions by absorbing stellar irradiation at high altitudes have not been identified despite extensive theoretical and observational effort. Her

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Pinard, Hugo. "Imagerie électromagnétique 2D par inversion des formes d'ondes complètes : Approche multiparamètres sur cas synthétiques et données réelles." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU041/document.

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Le radar géologique est une méthode d'investigation géophysique basée sur la propagation d'ondes électromagnétiques dans le sous-sol. Avec des fréquences allant de 5 MHz à quelques GHz et une forte sensibilité aux propriétés électriques, le géoradar fournit des images de réflectivité dans des contextes et à des échelles très variés : génie civil, géologie, hydrogéologie, glaciologie, archéologie. Cependant, dans certains cas, la compréhension fine des processus étudiés dans la subsurface nécessite une quantification des paramètres physiques du sous-sol. Dans ce but, l'inversion des formes d'on

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Ben, Youssef Atef. "Contrôle de têtes parlantes par inversion acoustico-articulatoire pour l’apprentissage et la réhabilitation du langage." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENT088/document.

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Les sons de parole peuvent être complétés par l'affichage des articulateurs sur un écran d'ordinateur pour produire de la parole augmentée, un signal potentiellement utile dans tous les cas où le son lui-même peut être difficile à comprendre, pour des raisons physiques ou perceptuelles. Dans cette thèse, nous présentons un système appelé retour articulatoire visuel, dans lequel les articulateurs visibles et non visibles d'une tête parlante sont contrôlés à partir de la voix du locuteur. La motivation de cette thèse était de développer un tel système qui pourrait être appliqué à l'aide à l'appr

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Böhm, Christian [Verfasser], Michael [Akademischer Betreuer] Ulbrich, Anton [Akademischer Betreuer] Schiela, and Georg [Akademischer Betreuer] Stadler. "Efficient Inversion Methods for Constrained Parameter Identification in Full-Waveform Seismic Tomography / Christian Böhm. Gutachter: Anton Schiela ; Georg Stadler ; Michael Ulbrich. Betreuer: Michael Ulbrich." München : Universitätsbibliothek der TU München, 2015. http://d-nb.info/1071948024/34.

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Böhm, Christian Verfasser], Michael [Akademischer Betreuer] [Ulbrich, Anton [Akademischer Betreuer] Schiela, and Georg [Akademischer Betreuer] Stadler. "Efficient Inversion Methods for Constrained Parameter Identification in Full-Waveform Seismic Tomography / Christian Böhm. Gutachter: Anton Schiela ; Georg Stadler ; Michael Ulbrich. Betreuer: Michael Ulbrich." München : Universitätsbibliothek der TU München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20150227-1232040-1-7.

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Cazenave, Quitterie. "Development and evaluation of multisensor methods for EarthCare mission based on A-Train and airborne measurements." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLV020.

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L'impact des nuages de glace sur le cycle de l'eau et le bilan radiatif est encore incertain en raison de la complexité des processus nuageux qui rend difficile l'acquisition d'observations adéquates sur les propriétés des nuages de glace et leur représentation dans les modèles de circulation générale. Les instruments de télédétection actifs et passifs, tels que les radiomètres, les radars et les lidars, sont couramment utilisés pour les étudier. La restitution des propriétés microphysiques des nuages (extinction, contenu en glace, rayon effectif, ...) peut être effectuée à partir d'un seul in

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