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1

Kannan, Ravishekar. "High order spectral volume and spectral difference methods on unstructured grids." [Ames, Iowa : Iowa State University], 2008.

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2

Lenz, Daniel. "Aspects of aperiodic order: spectral theory via dynamical systems." Doctoral thesis, [S.l.] : [s.n.], 2005. http://archiv.tu-chemnitz.de/pub/2005/0079.

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3

Binci, Massimiliano Kalidindi Surya. "A novel spectral framework for second-order homogenization theories /." Philadelphia, Pa. : Drexel University, 2008. http://hdl.handle.net/1860/2662.

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4

Mason, Colin Stuart. "Boundary perturbations and ultracontractivity of singular second order elliptic operators." Thesis, King's College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395943.

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5

Rossi, Lorenzo. "Functional renormalization group: higher order flows and pseudo-spectral methods." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18120/.

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Diamo una rapida introduzione alle idee su cui si basa il Gruppo di Rinormalizzazione Funzionale e deriviamo l’equazione di flsso esatta per l’azione effettiva media nella formulazione proposta da Wetterich e Morris. Lavorando in tale contesto, discutiamo i più comuni troncamenti LPA e LPA’ e li applichiamo a una teoria con un campo scalare reale in D dimensioni. Discutiamo la struttura dei puntifissi della teoria in dimensioni arbitrarie tramite un metodo numerico di shooting e concentrandoci sul caso D = 3, che corrisponde alla classe di universalità del modello di Ising, studiamo le soluzio
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6

Strauss, Michael. "Spectral pollution and higher order projection methods for operator pencils." Thesis, King's College London (University of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497989.

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7

Junior, Carlos Breviglieri. "High-order unstructured spectral finite volume method for aerodynamic applications." Instituto Tecnológico de Aeronáutica, 2010. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1133.

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An implicit finite volume algorithm is developed for higher-order unstructured computation of inviscid compressible flows. The Spectral Finite Volume method is used to achieve high-order spatial discretization of the domain, coupled with a matrix-free LU-SGS algorithm to solve the linear systems arising from implicit time marching of the governing equations, avoiding the explicit storage of the flux Jacobian matrices. A new limiter formulation for the high-order terms of the reconstruction polynomial is introduced. The issue of mesh refinement in accuracy measurements for unstructured meshes i
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8

Vanharen, Julien. "High-order numerical methods for unsteady flows around complex geometries." Phd thesis, Toulouse, INPT, 2017. http://oatao.univ-toulouse.fr/17967/1/vanharen.pdf.

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This work deals with high-order numerical methods for unsteady flows around complex geometries. In order to cope with the low-order industrial Finite Volume Method, the proposed technique consists in computing on structured and unstructured zones with their associated schemes: this is called a hybrid approach. Structured and unstructured meshes are then coupled by a nonconforming grid interface. The latter is analyzed in details with special focus on unsteady flows. It is shown that a dedicated treatment at the interface avoids the reflection of spurious waves. Moreover, this hybrid approach i
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9

Baker, Steven Jeffrey. "Spectral properties of displacement models." Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2007p/baker.pdf.

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Thesis (Ph. D.)--University of Alabama at Birmingham, 2007.<br>Additional advisors: Richard Brown, Ioulia Karpechina, Ryoichi Kawai, Boris Kunin. Description based on contents viewed Feb. 5, 2008; title from title screen. Includes bibliographical references (p. 73-75).
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10

Qin, Lihai. "Development of Reduced-Order Models for Lift and Drag on Oscillating Cylinders with Higher-Order Spectral Moments." Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/29542.

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An optimal solution of vortex-induced vibrations of structures would be a time-domain numerical simulation that simultaneously solves the fluid flow and structural response. Yet, the requirements in terms of computing power remains a major obstacle for implementing such a simulation. On the other hand, lower- or reduced-order models provide an alternative for determining structural response to forcing by fluid flow. The objective of this thesis is to provide a consistent approach for the development of reduced-order models for the lift and drag on oscillating cylinders and the identification o
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11

Owen, Mark Philip. "Topics in the spectral theory of fourth order elliptic differential operators." Thesis, King's College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244119.

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12

Claire, Narinder Singh. "Spectral theory and heat kernel estimates for higher order differential operators." Thesis, King's College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395811.

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13

Namburu, Visala. "Speech Coder using Line Spectral Frequencies of Cascaded Second Order Predictors." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35670.

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A major objective in speech coding is to represent speech with as few bits as possible. Usual transmission parameters include auto regressive parameters, pitch parameters, excitation signals and excitation gains. The pitch predictor makes these coders sensitive to channel errors. Aiming for robustness to channel errors, we do not use pitch prediction and compensate for its lack with a better representation of the excitation signal. We propose a new speech coding approach, Vector Sum Excited Cascaded Linear Prediction (VSECLP), based on code excited linear prediction. We implement forward
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14

Ong, Hannah Chien Leing. "Virus recognition in electron microscope images using higher order spectral features." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16186/1/Hannah_Chien_Leing_Ong_Thesis.pdf.

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Virus recognition by visual examination of electron microscope (EM) images is time consuming and requires highly trained and experienced medical specialists. For these reasons, it is not suitable for screening large numbers of specimens. The objective of this research was to develop a reliable and robust pattern recognition system that could be trained to detect and classify different types of viruses from two-dimensional images obtained from an EM. This research evaluated the use of radial spectra of higher order spectral invariants to capture variations in textures and differences in sym
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15

Ong, Hannah Chien Leing. "Virus recognition in electron microscope images using higher order spectral features." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16186/.

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Virus recognition by visual examination of electron microscope (EM) images is time consuming and requires highly trained and experienced medical specialists. For these reasons, it is not suitable for screening large numbers of specimens. The objective of this research was to develop a reliable and robust pattern recognition system that could be trained to detect and classify different types of viruses from two-dimensional images obtained from an EM. This research evaluated the use of radial spectra of higher order spectral invariants to capture variations in textures and differences in symmetr
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16

Feleqi, Ermal. "Spectral stability estimates for the eigenfunctions of second order elliptic operators." Doctoral thesis, Università degli studi di Padova, 2009. http://hdl.handle.net/11577/3421876.

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The thesis deals with a new direction in the spectral stability problem of elliptic operators, namely to find estimates for the variation of eigenfunctions due to domain perturbation. Unlike the problem of the variation of the eigenvalues, this problem had practically never been investigated previously. The approach developed in the thesis is based on the concept of "gap'' between linear operators. This concept, which measures the proximity of two unbounded linear operators, extends to the case of operators defined on different domains. Thereafter, there are obtained estimates of the gap
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17

Downes, Robert James. "Cosserat elasticity, spectral theory of first order systems, and the massless Dirac operator." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1417503/.

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This thesis is concerned with the study of the massless Dirac operator in dimension three and is, in part, based upon [12, 22, 21, 26, 25]. An introduction is given in Chapter 1. In Chapter 2 we study a special version of Cosserat elasticity, with deformations induced by rotations only, and no displacements. We prove that for a particular choice of elastic moduli and in the stationary setting (harmonic dependence on time) our mathematical model reduces to the massless Dirac equation. Chapter 3 contains a description of the progress recently made in the spectral theory of first order systems, w
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18

Fang, Y. L. "Analysis of first order systems on manifolds without boundary : a spectral theoretic approach." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1560979/.

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In this thesis we study first order systems of partial differential equations on manifolds without boundary. The thesis is, in part, based upon my publications. The importance of analysing first order systems can be seen directly from the special case, namely, the study of Dirac-type operators. In the first part, I assume my manifolds to be 4-dimensional and consider the simplest non-trivial first order linear differential operators on such manifolds. I give a systematic way of extracting the geometric content encoded within these operators. More importantly, a new concept called covariant sub
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19

Sobol, Zeev. "Some problems on the semigroups associated with second order elliptic expressions with singular real measurable coefficients." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340358.

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20

Smith, Euan Christopher. "Ultrafast third-order nonlinearities in novel zwitterionic molecules." Thesis, Heriot-Watt University, 1998. http://hdl.handle.net/10399/599.

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21

Ekelschot, Dirk. "Mesh adaptation strategies for compressible flows using a high-order spectral/hp element discretisation." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/43340.

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An accurate calculation of aerodynamic force coe cients for a given geometry is of fundamental importance for aircraft design. High-order spectral/hp element methods, which use a discontinuous Galerkin discretisation of the compressible Navier-Stokes equations, are now increasingly being used to improve the accuracy of flow simulations and thus the force coe cients. To reduce error in the calculated force coe cients whilst keeping computational cost minimal, I propose a p-adaptation method where the degree of the approximating polynomial is locally increased in the regions of the flow where lo
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22

Hao, Zhaopeng. "High-order numerical methods for integral fractional Laplacian: algorithm and analysis." Digital WPI, 2020. https://digitalcommons.wpi.edu/etd-dissertations/612.

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The fractional Laplacian is a promising mathematical tool due to its ability to capture the anomalous diffusion and model the complex physical phenomenon with long-range interaction, such as fractional quantum mechanics, image processing, jump process, etc. One of the important applications of fractional Laplacian is a turbulence intermittency model of fractional Navier-Stokes equation which is derived from Boltzmann's theory. However, the efficient computation of this model on bounded domains is challenging as highly accurate and efficient numerical methods are not yet available. The bottlene
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23

Harris, Robert Evan. "An adaptive quadrature-free implementation of the high-order spectral volume method on unstructured grids." [Ames, Iowa : Iowa State University], 2008.

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24

Huang, Yongxiang. "ARBITRARY ORDER HILBERT SPECTRAL ANALYSIS DEFINITION AND APPLICATION TO FULLY DEVELOPED TURBULENCE AND ENVIRONMENTAL TIME SERIES." Phd thesis, Université des Sciences et Technologie de Lille - Lille I, 2009. http://tel.archives-ouvertes.fr/tel-00439605.

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La Décomposition Modale Empirique (Empirical Mode Decomposition - EMD) ou la Transformation de Hilbert-Huang (HHT) est une nouvelle méthode d'analyse temps-fréquence qui est particulièrement adaptée pour des séries temporelles nonlinéaires et non stationnaires. Cette méthode a été proposée par NE. HUANG. il y a plus de dix ans. Pendant les dix dernières années, plus de 1000 articles ont appliqué cette méthode dans le cadre de diverses applications ou domaines de recherche. Dans cette thèse, nous appliquons cette méthode à des séries temporelles de turbulence, pour la première fois, et à des sé
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25

Vadsola, Mayank. "High-Order Spectral Element Method Simulation of Flow Past a 30P30N Three-Element High Lift Wing." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40964.

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The purpose of a multi-element high lift device is to increase lift dramatically while controlling the stall limit. The fluid flow over a multi-element high lift device has been explored widely both experimentally and numerically at high Reynolds numbers (O(10^6 )). The numerical simulations use turbulence models and hence details of the flow are not yet available. Low Reynolds number (O(10^4 )) flows over high lift devices have not been explored until recently. These lower Reynolds number flows have applications in the development of small aerial vehicles. The present work discusses bo
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26

Thomas, Gregory Robert. "A combined high-order spectral and boundary integral equation method for modelling wave interactions with submerged bodies." Thesis, Monterey, California. Naval Postgraduate School, 1996. http://hdl.handle.net/10945/8098.

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27

Thomas, Gregory Robert. "A combined high-order spectral and boundary integral equation method for modelling wave interactions with submerged bodies." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/17432.

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28

Barnes, Caleb J. "An Implicit High-Order Spectral Difference Method for the Compressible Navier-Stokes Equations Using Adaptive Polynomial Refinement." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1315591802.

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29

Durugo, Samuel O. "Higher-order airy functions of the first kind and spectral properties of the massless relativistic quartic anharmonic oscillator." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16497.

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This thesis consists of two parts. In the first part, we study a class of special functions Aik (y), k = 2, 4, 6, ··· generalising the classical Airy function Ai(y) to higher orders and in the second part, we apply expressions and properties of Ai4(y) to spectral problem of a specific operator. The first part is however motivated by latter part. We establish regularity properties of Aik (y) and particularly show that Aik (y) is smooth, bounded, and extends to the complex plane as an entire function, and obtain pointwise bounds on Aik (y) for all k. Some analytic properties of Aik (y) are also
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30

ITAKURA, Fumitada, Kazuya TAKEDA, and Tran Huy DAT. "Gamma Modeling of Speech Power and Its On-Line Estimation for Statistical Speech Enhancement." Institute of Electronics, Information and Communication Engineers, 2006. http://hdl.handle.net/2237/15052.

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31

Pérignon, Yves. "Modélisation déterministe des états de mer : application à la rétrodiffusion d'ondes radar." Ecole centrale de Nantes, 2011. https://tel.archives-ouvertes.fr/tel-00624645v2.

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Les études et développement menés dans ce travail de thèse ont porté sur divers aspects du traitement de l’évolution réaliste des états de mer, notamment sur les spécificités d’une approche déterministe non-linéaire, sur la prise en compte d’un forçage par le vent et de la dissipation dans une approche à phase résolue, et sur un développement à but opérationnel des techniques de modélisations réalistes. En parvenant à une meilleure modélisation des états de mer, ils visent à permettre une meilleure interprétation des images radar rétrodiffusées par la surface de la mer. Les applications concer
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32

Lu, Yunkai. "Random Vibration Analysis of Higher-Order Nonlinear Beams and Composite Plates with Applications of ARMA Models." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/29128.

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In this work, the random vibration of higher-order nonlinear beams and composite plates subjected to stochastic loading is studied. The fourth-order nonlinear beam equation is examined to study the effect of rotary inertia and shear deformation on the root mean square values of displacement response. A new linearly coupled equivalent linearization method is proposed and compared with the widely used traditional equivalent linearization method. The new method is proven to yield closer predictions to the numerical simulation results of the nonlinear beam vibration. A systematical investigation o
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33

Dorai-Raj, Sundardas Samuel. "First- and Second-Order Properties of Spatiotemporal Point Patterns in the Space-Time and Frequency Domains." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28540.

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Point processes are common in many physical applications found in engineering and biology. These processes can be observed in one-dimension as a time series or two-dimensions as a spatial point pattern with extensive amounts of literature devoted to their analyses. However, if the observed process is a hybrid of spatial and temporal point process, very few practical methods exist. In such cases, practitioners often remove the temporal component and analyze the spatial dependencies. This marginal spatial analysis may lead to misleading results if time is an important factor in the process. In
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34

Di, Donfrancesco Fabrizio. "Reduced Order Models for the Navier-Stokes equations for aeroelasticity." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS603.

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Le coût d’une simulation numérique aéroélastique peut devenir trop onéreuse lorsque une analyse paramétrique à haut fidélité est requise. Dans ce contexte, des Modèles d'Ordre Réduit (MOR) ont été développés en vue de réduire le coût de calcul des simulations numériques en préservant un haut niveau de précision. Ce travail de thèse porte sur la construction d'un MOR pour les équations de Navier-Stokes en tenant compte d'un maillage déformable dans le cas d'une application aéroélastique. Une base modale pour l'écoulement est obtenue via la Décomposition Orthogonale aux valeurs propres et une pr
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35

Lundquist, Tomas. "High order summation-by-parts methods in time and space." Doctoral thesis, Linköpings universitet, Beräkningsmatematik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-126172.

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This thesis develops the methodology for solving initial boundary value problems with the use of summation-by-parts discretizations. The combination of high orders of accuracy and a systematic approach to construct provably stable boundary and interface procedures makes this methodology especially suitable for scientific computations with high demands on efficiency and robustness. Most classes of high order methods can be applied in a way that satisfies a summation-by-parts rule. These include, but are not limited to, finite difference, spectral and nodal discontinuous Galerkin methods. In the
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36

Jaimes, Rafael. "Spatiotemporal Organization of Atrial Fibrillation Using Cross-Bicoherence with Surrogate Data." Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-theses/828.

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Atrial fibrillation (AF) is a troublesome disease often overlooked by more serious myocardial infarctions. Up until now, there has been very little or no use of high order spectral techniques in order to evaluate the organization of the atrium during AF. Cross-bicoherence algorithm can be used alongside a surrogate data threshold in order to determine significant phase coupling interactions, giving rise to an organizational metric. This proposed algorithm is used to show rotigaptide, a gap junction coupling drug, significantly increases the organization of the atria during episodes of AF due t
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37

Saccoletto, Marta. "La metrica di Agmon ed il decadimento esponenziale delle soluzioni di equazioni alle derivate parziali." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11437/.

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The aim of this master thesis is to study the exponential decay of solutions of elliptic partial equations. This work is based on the results obtained by Agmon. To this purpose, first, we define the Agmon metric, that plays an important role in the study of exponential decay, because it is related to the rate of decay. Under some assumptions on the growth of the function and on the positivity of the quadratic form associated to the operator, a first result of exponential decay is presented. This result is then applied to show the exponential decay of eigenfunctions with eigenvalues w
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38

Bassili, Niclas, and Douglas Eriksson. "An evaluation of deterministic prediction of ocean waves using pressure data to assist a Wave Energy Converter." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279600.

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Currently, existing devices for extracting electrical power from ocean waves all suffer from problems with low efficiency due to a lack of information about the incoming waves in advance. The complex dynamic nonlinear characteristics of the ocean make the prediction of these incoming waves a great challenge. This paper aims to investigate a deterministic short-term wave-by-wave prediction system, that can accurately predict the wave height and timing of the incoming waves, based on measurements from a submerged pressure sensor. The complete prediction process contains three steps, namely recon
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39

Perignon, Yves. "Modélisation déterministe des états de mer - Application à la rétrodiffusion d'ondes radar." Phd thesis, Ecole centrale de nantes - ECN, 2011. http://tel.archives-ouvertes.fr/tel-00624645.

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Les études et développement menés dans ce travail de thèse ont porté sur divers aspects du traitement de l'évolution réaliste des états de mer, notamment sur les spécificités d'une approche déterministe non-linéaire, sur la prise en compte d'un forçage par le vent et de la dissipation dans une approche à phase résolue, et sur un développement à but opérationnel des techniques de modélisations réalistes. En parvenant à une meilleure modélisation des états de mer, ils visent à permettre une meilleure interprétation des images radar rétrodiffusées par la surface de la mer. Les applications concer
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40

Ouladj, Maamar. "Optimisations des attaques par canaux cachés." Electronic Thesis or Diss., Paris 8, 2020. http://www.theses.fr/2020PA080019.

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L’ère numérique d’aujourd’hui relie tous les objets entre eux grâce à l’Internet des objets (IoT). Cela conduit à une omniprésence des systèmes embarqués, qui sont dotés de protocoles cryptographiques. Néanmoins, les implémentations de ces protocoles, entraînent des fuites d’informations sensibles pendant leur exécution. Les attaques par canaux auxiliaires (SCA) est un domaine dont l’objectif est l’analyse de ces fuites d’informations, afin de récupérer les paramètres secrets des protocoles.En fonction des habilités de l’adversaire, l’attaque optimale est soit l’analyse par corrélation de la c
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41

Pereira, Daniel de Almeida. "Efeito de não linearidades estruturais na resposta aeroelástica de aerofólios." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18148/tde-26072016-075942/.

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A aeroelasticidade estuda a interação mútua entre os efeitos aerodinâmicos e estruturais. É sabido que essa relação muitas vezes se comporta de maneira não linear, causando diversos problemas, tais como flutter, oscilações em ciclo limite, bifurcações e caos. Tais fenômenos são difíceis de serem diagnosticados, podendo causar problemas graves à estrutura das aeronaves e também inviabilizar as suas operações. Dentre as principais fontes de não linearidades em sistemas aeroelásticos, pode-se citar as de origem aerodinâmica e estrutural. As de origem estrutural, por sua vez, podem ter caráter dis
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42

Pester, Cornelia. "A posteriori error estimation for non-linear eigenvalue problems for differential operators of second order with focus on 3D vertex singularities." Doctoral thesis, Logos Verlag Berlin, 2005. https://monarch.qucosa.de/id/qucosa%3A18520.

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This thesis is concerned with the finite element analysis and the a posteriori error estimation for eigenvalue problems for general operator pencils on two-dimensional manifolds. A specific application of the presented theory is the computation of corner singularities. Engineers use the knowledge of the so-called singularity exponents to predict the onset and the propagation of cracks. All results of this thesis are explained for two model problems, the Laplace and the linear elasticity problem, and verified by numerous numerical results.
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43

BARBARINO, ANDREA. "Numerical Methods for Neutron Transport Calculations of Nuclear Reactors." Doctoral thesis, Politecnico di Torino, 2014. http://hdl.handle.net/11583/2561774.

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The objective of this thesis, which in clearly inspired by an industrial framework, is to try and narrow the gap between theoretical neutron modelling and application in the context of nuclear reactor design. This thesis is divided into three main chapters, preceded by a general overview. This structure reflects the three main topics which were chosen for this research project. The first topic develops the Spectral Element Method (SEM) approach and its use in conjunction with transport approximations. As it is documented in the specialized numerical analysis handbooks and in previous works by
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44

Quintard, Ludovic. "Caractérisation et contrôle des profils spatiaux, spectraux et temporels de faisceaux XUV obtenus par génération d’harmoniques d’ordres élevés dans des gaz." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0641/document.

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Dans ce travail nous présentons nos travaux réalisés sur le contrôle de la générationd’harmoniques d’ordres élevés dans les gaz. Dans un premiers temps nous montronscomment, en générant les harmoniques hors du foyer du faisceau IR, il est possiblede contrôler la phase spatiale des harmoniques dans le milieu générateur permettantd’obtenir un front d’onde divergent, collimaté ou convergent. Par cette méthode nousmontrons qu’il est possible de focaliser les harmoniques à des distances pouvant atteindresix longueur de Rayleigh après le point focal du faisceau IR. Nous avons ensuiteétudié des faisc
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45

Pester, Cornelia. "A posteriori error estimation for non-linear eigenvalue problems for differential operators of second order with focus on 3D vertex singularities." Doctoral thesis, Berlin Logos-Verl, 2006. http://deposit.ddb.de/cgi-bin/dokserv?id=2806614&prov=M&dok_var=1&dok_ext=htm.

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46

Huismann, Immo. "Computational fluid dynamics on wildly heterogeneous systems." TUDPress, 2018. https://tud.qucosa.de/id/qucosa%3A74002.

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In the last decade, high-order methods have gained increased attention. These combine the convergence properties of spectral methods with the geometrical flexibility of low-order methods. However, the time step is restrictive, necessitating the implicit treatment of diffusion terms in addition to the pressure. Therefore, efficient solution of elliptic equations is of central importance for fast flow solvers. As the operators scale with O(p · N), where N is the number of degrees of freedom and p the polynomial degree, the runtime of the best available multigrid algorithms scales with O(p · N) a
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47

Hunter, Aaron Matthew. "Arithmetic operations in first-order spectra." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq37553.pdf.

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48

Li, Qi. "Intermittency of Global Solar Radiation over Reunion island : Daily Mapping Prediction Model and Multifractal Parameters." Thesis, La Réunion, 2018. http://www.theses.fr/2018LARE0016/document.

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Les îles tropicales sont soumises à un ennuagement hétérogène et changeant rapidement. Par ailleurs, elles ont une ressource solaire importante mais significativement variable d’un jour à l’autre. Dans le sud-ouest de l’océan indien (SWIO), La Réunion fait partie de ces îles tropicales ayant un potentiel solaire colossal mais fortement intermittent. Dans cette étude, nous proposons une nouvelle approche de prévision déterministe des cartes journalières rayonnement solaire (SSR), basée sur quatre modèles de régression linéaire : une régression linéaire multiple (MLR), une régression en composan
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Cathelain, Marie. "Développement d’un modèle de simulation déterministe pour l’étude du couplage entre un écoulement atmosphérique et un état de mer." Thesis, Ecole centrale de Nantes, 2017. http://www.theses.fr/2017ECDN0001/document.

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La physique de la couche limite atmosphérique en domaine océanique est principalement régie par les processus couplés liés au vent, à l’état de mer local, et à des effets de flottabilité. Leur compréhension reste néanmoins parcellaire et leurs descriptions théoriques et stochastiques sont pour le moins lacunaires, lorsqu’elles ne sont tout simplement pas mises à mal par les rares observations. Dans un contexte d’exploitation croissante de la ressource éolienne offshore, la mise en place de méthodes numériques visant à une description plus fine des propriétés turbulentes de cette couche limite
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Vazquez, Thais Godoy. "Funções de interpolação e regras de integração tensorizaveis para o metodo de elementos finitos de alta ordem." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263500.

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Orientador: Marco Lucio Bittencourt<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica<br>Made available in DSpace on 2018-08-10T12:57:32Z (GMT). No. of bitstreams: 1 Vazquez_ThaisGodoy_D.pdf: 11719751 bytes, checksum: c6d385d6a6414705c9f468358b8d3bea (MD5) Previous issue date: 2008<br>Resumo: Este trabalho tem por objetivo principal o desenvolvimento de funções de interpolaçao e regras de integraçao tensorizaveis para o Metodo dos Elementos Finitos (MEF) de alta ordem hp, considerando os sistemas de referencias locais dos elementos. Para isso, primeira
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