Gotowa bibliografia na temat „Bornes non asymptotiques”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Spis treści
Zobacz listy aktualnych artykułów, książek, rozpraw, streszczeń i innych źródeł naukowych na temat „Bornes non asymptotiques”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Artykuły w czasopismach na temat "Bornes non asymptotiques"
COULOVRAT, F. "ANALYSE ASYMPTOTIQUE DE LA PROPAGATION DE FAISCEAUX BORNÉS GAUSSIENS NON LINÉAIRES". Le Journal de Physique Colloques 51, nr C2 (luty 1990): C2–1223—C2–1226. http://dx.doi.org/10.1051/jphyscol:19902287.
Pełny tekst źródłaRozprawy doktorskie na temat "Bornes non asymptotiques"
Mammeri, Youcef. "Sur quelques modèles asymptotiques dans la théorie des ondes hydrodynamiques". Thesis, Lille 1, 2008. http://www.theses.fr/2008LIL10040/document.
Pełny tekst źródłaThe Kadomtsev-Petviashvili equations (KP) describe the small amplitude long wave moving mainly in the x-direction in shallow water. As for ti Benjamin-Ono equation (BO), it describes such waves moving inside water. We are interested in these equations seen as equations of Benjamin-BonaMahony type (BBM). Our work is subdivided in three parts. ln the first one, we recall the modelling of the different equations. More particularly, we show that the BBM models are obtained from the fundamental principle of dynamics via an asymptotic analysis. We compare then the solutions of the KP equations, respectively of the BO one, with the solutions of the equations of BBM type. ln the second part, we are interested in sorne qualitative properties of the generalized equations of BBM type. Sorne results of continuation in time of bounds on Sobolev norms, decay in time and unique continuation of the solutions, are established. Finally, we conclude with a numerical study of the solutions of the generalized KP equations in space dimension 3. (n this last part, in collaboration with F. Hamidouche and S. Mefire, we inspect numerically the phenomena of dispersion, blow-up in finite time, solitonic behaviour and transverse instability
El, Korso Mohammed Nabil, i Korso Mohammed Nabil El. "Analyse de performances en traitement d'antenne. : bornes inférieures de l'erreur quadratique moyenne et seuil de résolution limite". Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00625681.
Pełny tekst źródłaMénard, Pierre. "Sur la notion d'optimalité dans les problèmes de bandit stochastique". Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30087/document.
Pełny tekst źródłaThe topics addressed in this thesis lie in statistical machine learning and sequential statistic. Our main framework is the stochastic multi-armed bandit problems. In this work we revisit lower bounds on the regret. We obtain non-asymptotic, distribution-dependent bounds and provide simple proofs based only on well-known properties of Kullback-Leibler divergence. These bounds show in particular that in the initial phase the regret grows almost linearly, and that the well-known logarithmic growth of the regret only holds in a final phase. Then, we propose algorithms for regret minimization in stochastic bandit models with exponential families of distributions or with distribution only assumed to be supported by the unit interval, that are simultaneously asymptotically optimal (in the sense of Lai and Robbins lower bound) and minimax optimal. We also analyze the sample complexity of sequentially identifying the distribution whose expectation is the closest to some given threshold, with and without the assumption that the mean values of the distributions are increasing. This work is motivated by phase I clinical trials, a practically important setting where the arm means are increasing by nature. Finally we extend Fano's inequality, which controls the average probability of (disjoint) events in terms of the average of some Kullback-Leibler divergences, to work with arbitrary unit-valued random variables. Several novel applications are provided, in which the consideration of random variables is particularly handy. The most important applications deal with the problem of Bayesian posterior concentration (minimax or distribution-dependent) rates and with a lower bound on the regret in non-stochastic sequential learning
El, Korso Mohammed Nabil. "Analyse de performances en traitement d'antenne : bornes inférieures de l'erreur quadratique moyenne et seuil de résolution limite". Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112074/document.
Pełny tekst źródłaThis manuscript concerns the performance analysis in array signal processing. It can bedivided into two parts :- First, we present the study of some lower bounds on the mean square error related to the source localization in the near eld context. Using the Cramér-Rao bound, we investigate the mean square error of the maximum likelihood estimator w.r.t. the direction of arrivals in the so-called asymptotic area (i.e., for a high signal to noise ratio with a nite number of observations.) Then, using other bounds than the Cramér-Rao bound, we predict the threshold phenomena.- Secondly, we focus on the concept of the statistical resolution limit (i.e., the minimum distance between two closely spaced signals embedded in an additive noise that allows a correct resolvability/parameter estimation.) We de ne and derive the statistical resolution limit using the Cramér-Rao bound and the hypothesis test approaches for the mono-dimensional case. Then, we extend this concept to the multidimensional case. Finally, a generalized likelihood ratio test based framework for the multidimensional statistical resolution limit is given to assess the validity of the proposed extension
Donier-Meroz, Etienne. "Graphon estimation in bipartite networks". Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAG010.
Pełny tekst źródłaMany real-world datasets can be represented as matrices where the entries represent interactions between two entities of different natures. These matrices are commonly known as adjacency matrices of bipartite graphs. In our work, we make the assumption that these interactions are determined by unobservable latent variables.Firstly, our main objective is to estimate the conditional expectation of the data matrix given the unobservable variables under the assumption that matrix entries are i.i.d. This estimation problem can be framed as estimating a bivariate function known as a graphon. In our study, we focus on two cases: piecewise constant graphons and Hölder-continuous graphons.We derive finite sample risk bounds for the least squares estimator. Additionally, we propose an adaptation of Lloyd's algorithm to compute an approximation this estimator and provide results from numerical experiments to evaluate the performance of these methods.Secondly, we address the limitations of the previous framework, which may not be suitable for modeling situations with bounded degrees of vertices, among other scenarios. Therefore, we extend our study to the relaxed independence assumption, where only the rows of the adjacency matrix are assumed to be independent. In this context, we specifically focus on piecewise constant graphons
Bacharach, Lucien. "Caractérisation des limites fondamentales de l'erreur quadratique moyenne pour l'estimation de signaux comportant des points de rupture". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS322/document.
Pełny tekst źródłaThis thesis deals with the study of estimators' performance in signal processing. The focus is the analysis of the lower bounds on the Mean Square Error (MSE) for abrupt change-point estimation. Such tools will help to characterize performance of maximum likelihood estimator in the frequentist context but also maximum a posteriori and conditional mean estimators in the Bayesian context. The main difficulty comes from the fact that, when dealing with sampled signals, the parameters of interest (i.e., the change points) lie on a discrete space. Consequently, the classical large sample theory results (e.g., asymptotic normality of the maximum likelihood estimator) or the Cramér-Rao bound do not apply. Some results concerning the asymptotic distribution of the maximum likelihood only are available in the mathematics literature but are currently of limited interest for practical signal processing problems. When the MSE of estimators is chosen as performance criterion, an important amount of work has been provided concerning lower bounds on the MSE in the last years. Then, several studies have proposed new inequalities leading to tighter lower bounds in comparison with the Cramér-Rao bound. These new lower bounds have less regularity conditions and are able to handle estimators’ MSE behavior in both asymptotic and non-asymptotic areas. The goal of this thesis is to complete previous results on lower bounds in the asymptotic area (i.e. when the number of samples and/or the signal-to-noise ratio is high) for change-point estimation but, also, to provide an analysis in the non-asymptotic region. The tools used here will be the lower bounds of the Weiss-Weinstein family which are already known in signal processing to outperform the Cramér-Rao bound for applications such as spectral analysis or array processing. A closed-form expression of this family is provided for a single and multiple change points and some extensions are given when the parameters of the distributions on each segment are unknown. An analysis in terms of robustness with respect to the prior influence on our models is also provided. Finally, we apply our results to specific problems such as: Gaussian data, Poisson data and exponentially distributed data
Pokorný, Milan. "Comportement asymptotique des solutions de quelques équations aux dérivées partielles decrivant l'écoulement de fluides dans les domaines non-bornes". Toulon, 1999. http://www.theses.fr/1999TOUL0003.
Pełny tekst źródłaWe consider two different problems here. In the first part we study the asymptotic behaviour at, infinity of solutions to equations describing steady flow of certain classes of non-Newtonian fluid, the other part concerns threedi-rnensional flow of viscous and ideal fluid in the whole space. We first introduce several models of fluids and the systems of equations describing, the stationary flow of the non-Newtonian fluids are reformulated in order to point up their mixed hyperbolic elliptic character. The next part is devoted to a detailed study of certain linear problems; we first, consider the (classical) Oseen problem, where the greatest interest is devoted to the weighted estimates of both singular and weakly singular integral operators with kernels corresponding to the fundamental solution to the Oseen problem and its derivatives. Next we study the so-called modified Oseen problem, i. E. A small linear perturbation of the classical Oseen problem. Further we summarize and slightly extend the results on the steady transport equation. Afterwards, these results are used in the construction of solutions and the study of the asymptotic properties of solutions to the systems of equations describing the stationary flow of certain classes of viscoeiastic fluids past an obstacle. We show that for sufficiently slow flows the a. Symptotic properties of the solution correspond to those of the fundamental solution to the Oseen problem. In the other part of the thesis we consider non stationary flow of both linearly viscous and ideal fluid in the whole space. We show that under the additional a. Ssumption of the axial symmetry of the data, the solution is smooth if the data are smooth and therefore unique in the class of all weak solutions
Côte, Delphine. "Vortex et données non bornées pour les équations de Ginzburg-Landau paraboliques". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066002.
Pełny tekst źródłaWe are interested in this thesis in evolution equations related to the Ginzburg-Landau functionals, of parabolic nature. Our goal is to describe the temporal behavior of limiting solutions as a small penalisation parameter tends to 0.In the first chapter, we retrace in a synthetic way the remarkable study by Bethuel, Orlandi and Smets on the parabolic Ginzburg-Landau equation in dimension 2 : the evolution of point vortices is governed by the gradient flow of the Kirchoff-Onsager functionnal modified by a drift term ; it is smooth away from the merging and splitting times ; these phenomenon are subject to conservation of the local degree and energy dissipation.In the second chapter, we consider the Cauchy problem for systems of semi-linear parabolic equations. Motivated by the example of the vortices, we construct, for defocusing nonlinearities, global solutions to the associated integral equation with intial data unbounded in space (allowed to grow like exp(x^2)). In the case of focusing nonlinearities, we show a phenomenon of instantaneous blow-up.In the third chapter, we go back to the parabolic Ginzburg-Landau equation. We replace the energy bound of Bethuel, Orlandi et Smets by a local-in-space bound on the energy. This allows to consider general configurations of vortices without the help of « vanishing vortices ». We extend their analysis, and show various results of decomposition of the renormalized energy, and that the concentrated energy moves according to the mean curvature flow
Pinto, Manuel. "Des inegalites fonctionnelles et leurs applications". Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13097.
Pełny tekst źródłaHarrat, Ayoub. "Problème de moments avec applications et estimations du spectre discret des opérateurs définis par des matrices infinies non bornées THE QUINTIC COMPLEX MOMENT PROBLEM ASYMPTOTIC EXPANSION OF LARGE EIGENVALUES FOR A CLASS OF UNBOUNDED JACOBI MATRICES". Thesis, Littoral, 2020. http://www.theses.fr/2020DUNK0563.
Pełny tekst źródłaIn this thesis, we first provide a concrete solution to the, almost all, quintic TCMP (that is, when m = 5). We also study the cardinality of the minimal representing measure. Based on the bi-variate recurrence sequence properties with some Curto-Fialkow's results. Our method intended to be useful for all odd-degree moment problems. Second, we investigate the full moment problem for discrete measures using Vasilescu's idempotent approach based on Λ-multiplicative elements with respect to the associated square positive Riesz functional. We give a sufficient condition for the existence of a discrete integral representation for the associated Riesz functional, which turns to be necessary in bounded shift space case. A particular attention is given to Λ-multiplicative elements, where a total description, for the cases where they are a single point indicator functions, is given. Lastly, We investigate a class of infinite Jacobi matrices which define unbounded self-adjoint operators with discrete spectrum. Our purpose is to establish the asymptotic expansion of large eigenvalues and to compute two correction terms explicitly. This method works in general for band matrices but Jacobi matrices case still much interesting due to applications and explicit expressions obtained for the first correction terms in the asymptotic formula