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Toomire, Bruce Vincent. "Studies in the Wigner-Poisson and Schroedinger-Poisson Systems." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/29464.
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The need to model the quantum effects in semiconductor devices such as resonance tunneling diodes and quantum dots has lead to an intense study of the Wigner-Poisson (WP) and Schroedinger-Poisson (SP) systems. In this work we present the mathematical analysis of several related models for these systems. These include: a time-dependent model of dissipation in (SP), a quasi-linear (SP) system, a study of the stationary (WP)-(SP) problem with a discussion of the quantum analogue of classical BGK modes and a proof of existence of eigenfunctions for (SP) with periodic boundary conditions, and an examination of the stationary Wigner equations with inflow" boundary conditions. Finally, a proposed numerical scheme for the stationary (SP) system with Boltzmann distribution functions is shown along with its corresponding Bloch equation.Ph. D.
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Lecoutre, César. "Polynomial Poisson algebras : Gel'fand-Kirillov problem and Poisson spectra." Thesis, University of Kent, 2014. https://kar.kent.ac.uk/47941/.
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We study the fields of fractions and the Poisson spectra of polynomial Poisson algebras. First we investigate a Poisson birational equivalence problem for polynomial Poisson algebras over a field of arbitrary characteristic. Namely, the quadratic Poisson Gel'fand-Kirillov problem asks whether the field of fractions of a Poisson algebra is isomorphic to the field of fractions of a Poisson affine space, i.e. a polynomial algebra such that the Poisson bracket of two generators is equal to their product (up to a scalar). We answer positively the quadratic Poisson Gel'fand-Kirillov problem for a large class of Poisson algebras arising as semiclassical limits of quantised coordinate rings, as well as for their quotients by Poisson prime ideals that are invariant under the action of a torus. In particular, we show that coordinate rings of determinantal Poisson varieties satisfy the quadratic Poisson Gel'fand-Kirillov problem. Our proof relies on the so-called characteristic-free Poisson deleting derivation homomorphism. Essentially this homomorphism allows us to simplify Poisson brackets of a given polynomial Poisson algebra by localising at a generator. Next we develop a method, the characteristic-free Poisson deleting derivations algorithm, to study the Poisson spectrum of a polynomial Poisson algebra. It is a Poisson version of the deleting derivations algorithm introduced by Cauchon [8] in order to study spectra of some noncommutative noetherian algebras. This algorithm allows us to define a partition of the Poisson spectrum of certain polynomial Poisson algebras, and to prove the Poisson Dixmier-Moeglin equivalence for those Poisson algebras when the base field is of characteristic zero. Finally, using both Cauchon's and our algorithm, we compare combinatorially spectra and Poisson spectra in the framework of (algebraic) deformation theory. In particular we compare spectra of quantum matrices with Poisson spectra of matrix Poisson varieties.
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Damianou, Pantelis Andrea. "Nonlinear Poisson brackets." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184704.
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A hierarchy of vector fields (master symmetries) and homogeneous nonlinear Poisson structures associated with the Toda lattice are constructed and the various connections between them are investigated. Among their properties: new brackets are generated from old ones by using Lie-derivatives in the direction of certain vector fields; the infinite sequences obtained consist of compatible Poisson brackets in which the constants of motion for the Toda lattice are in involution. The vector fields in the construction are unique up to addition of a Hamiltonian vector field. Similarly the Poisson brackets are unique up to addition of a trivial Poisson bracket. These are Poisson tensors generated by wedge products of Hamiltonian vector fields. The non-trivial brackets may also be obtained by the use of r-matrices; we give formulas and prove this for the quadratic and cubic Toda brackets. We also indicate how these results can be generalized to other (semisimple) Toda flows and we give explicit formulas for the rank 2 Lie algebra of type B₂. The main tool in this calculation is Dirac's constraint bracket formula. Finally we study nonlinear Poisson brackets associated with orbits through nilpotent conjugacy classes in gl(n, R) and formulate some conjectures. We determine the degree of the transverse Poisson structure through such nilpotent elements in gl(n, R) for n ≤ 7. This is accomplished also by the use of Dirac's bracket formula.
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Al-Shujary, Ahmed. "Kähler-Poisson Algebras." Licentiate thesis, Linköpings universitet, Matematik och tillämpad matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-150620.
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The focus of this thesis is to introduce the concept of Kähler-Poisson algebras as analogues of algebras of smooth functions on Kähler manifolds. We first give here a review of the geometry of Kähler manifolds and Lie-Rinehart algebras. After that we give the definition and basic properties of Kähler-Poisson algebras. It is then shown that the Kähler type condition has consequences that allow for an identification of geometric objects in the algebra which share several properties with their classical counterparts. Furthermore, we introduce a concept of morphism between Kähler-Poisson algebras and show its consequences. Detailed examples are provided in order to illustrate the novel concepts.The series name is corrected in the electronic version of the cover.
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Arnal, Céline. "Ecologie comportementale de la symbiose poisson nettoyeur/poisson client : motivations et honnêteté." Perpignan, 2000. http://www.theses.fr/2000PERP0379.
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La symbiose de nettoyage implique un poisson "nettoyeur" qui nettoie le corps de poissons "clients". Cette relation a lieu dans le territoire du poisson nettoyeur : la station de nettoyage. Les nettoyeurs intègrent, lors de leur inspection, des ectoparasites, des écailles et du mucus. Malgré le nombre croissant d'études sur la symbiose de nettoyage, le gain énergétique net issu de cette relation pour les deux protagonistes reste encore à déterminer. Il apparaît ainsi difficile de définir précisement la véritable nature de la relation. Dans ce travail, deux questions principales ont été posées : 1)quels facteurs influencent la symbiose de nettoyage?, et 2) les nettoyeurs sont-ils honnêtes? Quatre espèces de nettoyeurs, issus de trois localités différentes, ont été étudiés : Symphodus melanocercus (Banyuls-sur- Mer), Labroides dimidiatus (Lizard Isaland et Moorea), et les gobies Elacatinus evelynae et Elacatinus prochilos (La Barbade). Une approche de terrain a été utilisée, avec des observations comportementales, des mesures de l'alimentation des nettoyeurs, du parasitisme et des caractéristiques du mucus de leurs clients. Suite à l'étude de chacune des espèces, une comparaison inter-spécifique a été effectuée. L'honnêteté apparaît comme une stratégie importante dans la relation de nettoyage. Ce sont les clients les plus parasités qui visitent le plus les stations de leurs clients. L'honnêteté des nettoyeurs peut, cependant, varier en fonction de plusieurs facteurs comme : l'abondance en ectoparasites, la sexualité, et la localisation de la station de nettoyage. Enfin, il apparaît que chaque espèce de nettoyeur est caractérisée par une spécialisation trophique déterminée, et que les nettoyeurs tropicaux sont plus spécialistes que les nettoyeurs de régions tempéréesCleaning symbiosis involves a cleaner fish, which cleams the body surface of client fishes. The relationship generally occurs in the cleaner territory : the cleaning station, Cleaner fishes remove ectoparasites, scales and mucus when inspecting their client fishes. Despite years of studies, the net fitness of the two protagonists are still not fully understood. It is, thus, difficult to define clearly this relationship. In this study, two main questions have been asked : 1)what factors influence cleaning interactions? and 2) is the cleaner fish behaviour honest? Four species of cleaner fishes from three localities were studied : Symphodus melanocercus (Banyuls-sur- Mer), Labroides dimidiatus (Lizard Isaland et Moorea), and the gobies Elacatinus evelynae and Elacatinus prochilos (Barbados). Field work experiments were conducted through behavioural observations, and direct measurement of cleaners' diet, clients' ectoparasitim and mucus characteristics. Each species was studied separately, and a comparative analysis was performed. Honesty appears to be an important strategy in cleaning symbioses. The most parasited clients visit cleaning stations higher rates, and ectoparasites are the major items removed by cleaner fishes. Cleaner fish honesty shows variations, depending on ectoparasites density, sex, and the localisation of the cleaning station. Finally, cleaning specialisation appears to be species-specific, which more specialised cleaners in tropical than in temperate waters
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Bertozzi, Luca. "Formula integrale di Poisson." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10034/.
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Il tema centrale di questa tesi è lo studio del problema di Dirichlet per il Laplaciano in R^2 usando le serie di Fourier. Il problema di Dirichlet per il Laplaciano consiste nel determinare una funzione f armonica e regolare in un dominio limitato D quando sono noti i valori che f assume sul suo bordo. Ammette una sola soluzione, ma non esistono criteri generali per ricavarla. In questa tesi si mostra come la formula integrale di Poisson, sotto determinate condizioni, risolva il problema di Dirichlet in R^2 e in R^n.
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Zocher, Mathias. "Multivariate Mixed Poisson Processes." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2005. http://nbn-resolving.de/urn:nbn:de:swb:14-1134744627176-09576.
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Multivariate mixed Poisson processes are special multivariate counting processes whose coordinates are, in general, dependent. The first part of this thesis is devoted to properties which multivariate counting processes may possess. Such properties are, for example, the Markov property, the multinomial property and regularity. With regard to regularity we study the properties of transition probabilities and intensities. The second part of this thesis restricts the class of all multivariate counting processes by additional assumptions leading to different types of multivariate mixed Poisson processes which, however, are connected with each other. Using a multivariate version of the Bernstein-Widder theorem, it is shown that multivariate mixed Poisson processes are characterized by the multinomial property. Furthermore, regularity of multivariate mixed Poisson processes and properties of their moments are studied in detail. Throughout this thesis, two types of stability of properties of multivariate counting processes are studied: It is shown that most properties of a multivariate counting process are stable under certain linear transformations including the selection of single coordinates and summation of all coordinates. It is also shown that the different types of multivariate mixed Poisson processes under consideration are in a certain sense stable in time.
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Beltrán, Johel. "Medida aleatoria de Poisson." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/96813.
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In this monograph we continue with the inspection initiated in [1] on the fundamental tools introduced in the approach proposed in [2,3] for the study of metastability. We give the definition of the Poisson random measures and prove the main properties that we will subsequently use to construct Markov processes with finite state space. Such construction will allow us to provide a probabilistic proof of the fact that the law of a Markov process solves the martingal problem.En esta monografía continuamos con el desarrollo iniciado en [1] sobre las herramientas fundamentales usadas en el abordaje propuesto en [2,3] para el estudio de la metaestabilidad. Definimos las medidas aleatorias de Poisson y probamos las principales propiedades que seran usadas para construir procesos de Markov con espacio de estados finito. Esta forma de abordar la propiedad Markoviana nos permitirá dar una demostración probabilística de que la ley de un proceso de Markov resuelve un problema martingala.
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Abbaci, Mohamed. "Espaces homogènes de Poisson." Lyon 1, 1986. http://www.theses.fr/1986LYO11705.
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On fait l'etude geometrique des espaces homogenes de poisson. Dans le cas des espaces a feuilles fermees, on etudie ceux de type hamiltonien. On etablit un theoreme de structure qui permet de les classer, et un resultat sur une realisation reguliere d'un espace homogene de poisson de type hamiltonien
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Chloup-Arnould, Véronique. "Groupes de Lie-Poisson." Metz, 1996. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1996/Chloup_Arnould.Veronique.SMZ9619.pdf.
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Dans cette thèse nous étudions les structures de Lie-Poisson. De manière plus précise deux thèmes sont abordés. Le premier est de nature classificatoire. Nous donnons une description complète des algèbres de Manin (c'est-à-dire les grandes algèbres d'un triple de Manin) associées à des structures de bigèbre de lie sur une algèbre de lie réelle semi-simple. Ensuite, en adaptant au cas réel les résultats de Belavin et Drinfeld décrivant les solutions de l'équation de Yang-Baxter standard modifiée non nulle sur une algèbre de lie semi-simple complexe, nous donnons les solutions générales de l'équation de Yang-Baxter modifiée standard non nulle sur une algèbre de lie réelle semi-simple. Enfin nous donnons des résultats partiels concernant les structures de bigèbre liées aux solutions de l'équation de Yang-Baxter modifiée non standard sur une algèbre de lie réelle simple telle que sa complexifiée ne soit pas simple. Le deuxième thème est celui de la linéarisation locale d'une structure de lie-poisson. Nous montrons, en utilisant le théorème de linéarisation analytique dans le cas d'une structure de poisson de j. Conn, que si (g,p) est un groupe de lie-poisson, et si l'algèbre duale est la somme directe d'un idéal semi-simple et d'un idéal abélien, alors p est analytiquement linéarisable dans un voisinage de l'identité. Dans le cadre d'une structure de poisson générale cette proposition peut-être mise en défaut. Nous montrons par ailleurs que toute structure de lie-poisson exacte sur un groupe de lie nilpotent de pas deux est linéaire, sur un groupe de lie nilpotent de pas trois et de dimension inferieure ou égale a six est linéarisable et qu'il existe des structures de lie-poisson exactes sur un groupe de lie nilpotent de pas quatre et de dimension cinq qui ne sont pas linéarisables
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Haraki, Abdeljalil. "Structures de Poisson quadratiques." Montpellier 2, 1993. http://www.theses.fr/1993MON20223.
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Dans un premier chapitre, on associe a chaque structure de poisson des isomorphismes infinitesimaux d'un type special, appeles rotationnels de la structure. Utilisant ces rotationnels, on definit une strategie de classification a isomorphismes lineaires pres, des structures de poisson quadratiques. Cette strategie donne une classification complete en dimension 3, partielle en dimension 4, et permet d'obtenir generiquement les modeles des structures de poisson quadratiques en toute dimension. Dans le second chapitre, on montre la non-degenerescence formelle des structures de poisson quadratiques dont le rotationnel possede des valeurs propres ne verifiant pas certaines relations de non-resonance. Au passage, on donne generiquement une forme normale formelle des structures de poisson dont le 1-jet est nul en un point. Enfin, dans le cas de la dimension 3, on montre qu'on peut associer a toute structure de poisson quadratique a rotationnel inversible, une action commutative de r#2 sur r#3, donnee par le rotationnel et un autre champ de vecteurs. Lorsque cette action est non resonnante et hyperbolique, on montre que la structure de poisson quadratique associee est non-degeneree au sens differentiable
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CHLOUP-ARNOULD, VERONIQUE GUTT S. "GROUPES DE LIE-POISSON /." [S.l.] : [s.n.], 1996. ftp://ftp.scd.univ-metz.fr/pub/Theses/1996/Chloup_Arnould.Veronique.SMZ9619.pdf.
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Guerri, Silvia. "I processi di Poisson." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2589/.
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El, Hadrami Mohamed Lemine Ould 1962. "Poisson algebras and convexity." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/290675.
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In this dissertation, we identify a subgroup Tˢ of Dˢ(μ), the group of Sobolev symplectomorphisms of CP (n), n = 1,2 that has all the properties of a torus of a compact finite dimensional Lie group. We prove that Tˢ: (1) topologically is a submanifold of Dˢ(μ); (2) algebraically is a maximal abelian subgroup of Dˢ(μ); (3) geometrically is flat and totally geodesic. We also characterize the doubly stochastic operators on measurable spaces and use this result to extend the convexity Theorem of T. Bloch, H. Flaschka and T. Ratiu.
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Casati, Matteo. "Multidimensional Poisson Vertex Algebras and Poisson cohomology of Hamiltonian structures of hydrodynamic type." Doctoral thesis, SISSA, 2015. http://hdl.handle.net/20.500.11767/4853.
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The Poisson brackets of hydrodynamic type, also called Dubrovin-Novikov brackets, constitute the Hamiltonian structure of a broad class of evolutionary PDEs, that are ubiquitous in the theory of Integrable Systems, ranging from Hopf equation to the principal hierarchy of a Frobenius manifold. They can be regarded as an analogue of the classical
Poisson brackets, defined on an infinite dimensional space of maps Σ → M between two manifolds. Our main problem is the study of Poisson-Lichnerowicz cohomology of such space when dim Σ > 1. We introduce the notion of multidimensional Poisson Vertex Algebras, generalizing and adapting the theory by A. Barakat, A. De Sole, and V. Kac [Poisson Vertex Algebras in the theory of Hamiltonian equations, 2009]; within this framework we explicitly compute the first nontrivial cohomology groups for an arbitrary Poisson bracket of hydrodynamic type, in the case dim Σ = dim M = 2. For the case of the so-called scalar brackets, namely the ones for which dim M = 1, we give a complete description on their Poisson–Lichnerowicz cohomology. From this computations it
follows, already in the particular case dim Σ = 2, that the cohomology is infinite dimensional.
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Thiffault, Johanne. "Estimation for homogeneous Poisson processes." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63370.
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Lares, Santos Asin. "Deformation quantization on poisson manifolds." Thesis, University of Warwick, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340626.
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Streftaris, George. "Bayesian methods for Poisson models." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/14505.
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To account for overdispersion in count data, that is variation in excess of that justified from the assumed model, one may consider an additional source of variation, by assuming that each observation, Yi, i = 1, ..., m, arises from a conditionally independent Poisson distribution, given its respective mean qi, i = 1, ..., m. We review various frequentist methods for the estimation of the Poisson parameters qi, i = 1, ..., m, which are based on the inadmissibility of the usual unbiased maximum likelihood estimator, in terms of the associated risk in dimensions greater than two. The so called shrinkage estimators adjust the maximum likelihood estimates towards a fixed or data-determined point, abandoning unbiasedness in favour of lower risk. Inferences for the parameters of interest can also be drawn employing Bayesian methods. Conjugate models are often adopted to facilitate the computational procedure. In this thesis we assume a nonconjugate log-normal prior distribution, which allows for more dispersion in the Poisson means and can also accommodate a correlation structure. We derive two empirical Bayes estimators, which approximate the posterior mean. The first is based on a linear shrinkage rule, while the second employs a non-iterative importance sampling technique. The frequency properties of the two estimators in terms of average risk are assessed and compared to other estimating approaches proposed in the literature. A full hierarchical Bayes analysis is also considered, assuming both informative and non-informative prior distributions at the lower stage of the hierarchy. Some analytical posterior inferences, based on simple approximations are obtained. We then employ stochastic simulation techniques, suggesting two Markov chain Monte Carlo methods which involve the Gibbs sampler and a hybrid strategy. They rely on a log-normal/gamma mixture approximation to the full conditional posterior distribution of the parameters qi, i = 1, ,..., m. The shrinkage behaviour of the hierarchical Bayes estimator is explored, and its average risk is examined through frequency simulations. Examples and applications of the considered methods are given throughout the thesis.
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Costa, Paulo Henrique Pereira da 1983. "Difusões em variedades de poisson." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/306283.
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Orientador: Paulo Regis Caron RuffinoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
Made available in DSpace on 2018-08-13T23:01:19Z (GMT). No. of bitstreams: 1 Costa_PauloHenriquePereirada_M.pdf: 875708 bytes, checksum: 8862a1813f1bb85b5d0269462a80501e (MD5) Previous issue date: 2009
Resumo: O objetivo desse trabalho é estudar as equações de Hamilton no contexto estocástico. Sendo necessário para tal um pouco de conhecimento a cerca dos seguintes assuntos: cálculo estocástico, geometria de segunda ordem, estruturas simpléticas e de Poisson. Abordamos importantes resultados, dentre eles o teorema de Darboux (coordenadas locais) em variedades simpléticas, teorema de Lie-Weinstein que de certa forma generaliza o teorema de Darboux em variedades de Poisson. Veremos que apesar de o ambiente natural para se estudar sistemas hamiltonianos ser variedades simpléticas, no caso estocástico esses sistemas se adaptam bem em variedades de Poisson. Além disso, para atingir a nossa meta, estudaremos equações diferenciais estocásticas em variedades de dimensão finita usando o operador de Stratonovich
Abstract: This dissertation deals with transfering Hamilton's equations in stochastic context. This requires some knowledge about the following: stochastic calculus, second order geometry and Poisson and simplectic structures. Important results that will be discussed in this theory are Darboux's theorem (local coordinates) for simplectic manifolds, and Lie-Weintein's theorem that is in a certain way of Darboux's theorem on Poisson manifolds. We will see that although the natural environment for studying hamiltonian systems is symplectic manifolds, if we have a Poisson structure we will still be able to study them. Moreover, to achieve our goal, we will study stochastic differential equations on finite dimensional manifolds using the Stratonovich operator
Mestrado
Geometria Estocastica
Mestre em Matemática
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Arruda, Marcelo Leme de. "Poisson, Bayes, Futebol e DeFinetti." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/45/45133/tde-19072012-112940/.
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Nesta dissertação é abordado o problema de previsões probabilísticas para eventos tricotômicos, além da questão de comparação de qualidade das previsões através de curvas de calibração e da Medida de DeFinetti. É feita uma aplicação paraprevisões de resultados de futebolThis dissertation deals with the problem of probabilistic previsions for tricotomic events, in addiction with the question of comparison of quality of the previsions, by using calibration curves and the DeFinetti Measure. An application is developed for previsions of soccer games results.
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Edou, Ebolo Clet Mesmin. "Marché du poisson au Gabon." Montpellier 3, 1993. http://www.theses.fr/1993MON30028.
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La mise a disposition du consommateur gabonais des produits halieutiques issus des zones de production implique un cheminement des produits a travers de nombreuses operations techniques. Les premieres etapes du marche comprennent la capture, le conditionnement et le groupage des produits de la peche. Ils se deroulent sur les lieux de production et sont suivis de l'expedition sur les marches. L'etape suivante de la distribution est constituee par la commercialisation puis la consommation de ces produits par differentes familles. Cependant la commercialisation du poisson est confrontee a plusieurs problemes. La situation actuelle se caracterise par l'insuffisance et la mauvaise qualite de l'equipement des revendeurs de poissons et de l'equipement routier, des marches souvent insalubres, des infrastructures de mises a terre et de conditionnement inadaptees voire inexistances. Il est a craindre, dans ces conditions, que les differents projets de developpement du marche des produits halieutiques ne puissent voir le jourTo put halieutic products at gabonese consumers' disposal, one should follow severals technical operations. This first steps of marketing deal with capture, conditioning and bulking of commodities. They take place in the production areas before being dispatched on marketplaces. The following stage deals with handling and consumption by different households. However handling of halieutic products encounters many problems : - shortage and bad quality of fish retailers' equipment - insufficiency and bad quality of roads - maladjusted or non-existent of landing and conditioning infrastructures. In such conditions, one should fear the non realization of fish-markets development projects
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Wade, Aïssa. "Normalisation de structures de Poisson." Montpellier 2, 1996. http://www.theses.fr/1996MON20117.
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Molinier, Jean-Christophe. "Linéarisation de structures de Poisson." Montpellier 2, 1993. http://www.theses.fr/1993MON20006.
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Soit (m, p) une variete de poisson de rang nul a l'origine. Si l'on considere le developpement en serie de taylor du tenseur p, on peut ecrire p=p#l+r ou p#l designe la partie lineaire de p et ou r est d'ordre superieur a 2. On dit que p est linearisable (formellement, analytiquement ou differentiablement) si p est localement diffeomorphe (au sens precise) a p#l. Si l'on note que les coefficients de p#l sont les constantes de structures d'une algebre de lie g, on dira que g est non degeneree pour exprimer que toutes les structures de poisson associees a g sont linearisables. Ce travail debute sur l'etude des algebres de lie de dimension 4 et des arguments geometriques permettent de demontrer qu'elles sont toutes degenerees sauf 4 algebres particulieres. Ceci amene dans un second chapitre a demontrer la non-degenerescence formelle de g#2x. . . Xg#2 (n fois) ainsi que la non-degenerescence differentiable de g#2g#2 en utilisant des techniques de changement de variables, ainsi que la notion de rotationnel (ou g#2 est l'algebre de lie de dimension 2 non triviale). Enfin nous generalisons un travail de j. F. Conn pour demontrer la non-degenerescence des algebres du type produit direct gr ou g est semi-simple
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GAVARINI, FABIO. "Quantizzazione di gruppi di Poisson." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 1996. http://hdl.handle.net/2108/40610.
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Sia G ^\tau un gruppo algebrico semisemplice connesso e semplicemente connesso, dotato della struttura di gruppo di Poisson di Sklyanin-Drinfel’d generalizzata; sia H^\tau il suo gruppo di Poisson duale.
Mediante la costruzione del doppio quantico e la dualizzazione tramite algebre di Hopf formali, costruiamo nuovi gruppi quantici U^M_{q,\varphi}(h) — duali dei gruppi quantici multiparametrici U^{M'}_{q,\varphi}(g) costruiti su g^\tau , con g = Lie(G) — che danno quantizzazioni infinitesimali di H ^\tau e G^\tau ; studiamo le loro specializzazioni alle radici dell'unità (in particolare, i loro limiti classici), scoprendo così nuovi morfismi di Frobenius quantici. L'intera descrizione dualizza per H ^\tau quel che era noto per G^\tau , completando la quantizzazione della coppia (G^\tau,H^\tau).Let G ^\tau be a connected simply connected semisimple algebraic group, endowed with generalized Sklyanin-Drinfel’d structure of Poisson group; let H^\tau be its dual Poisson group. By means of quantum double construction and dualization via formal Hopf algebras, we construct new quantum groups U^M_{q,\varphi}(h) — dual to the multiparameter quantum group U^{M'}_{q,\varphi}(g) built upon g^\tau , with g = Lie(G) — which yield infinitesimal quantization of H ^\tau and G^\tau ; we study their specializations at roots of 1 (in particular, their classical limits), thus discovering new quantum Frobenius morphisms. The whole description dualize for H ^\tau what was known for G^\tau , completing the quantization of the pair (G^\tau , H^\tau).
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Monnier, Philippe. "Une cohomologie associée à une fonction. Applications aux cohomologies de Poisson et de Nambu-Poisson." Montpellier 2, 2001. http://www.theses.fr/2001MON20083.
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Juhel, Frédéric. "Etude de l'application de deux nouvelles opérations de séchage, texturation du poisson : analyse comparative du procédé et du produit." La Rochelle, 2000. http://www.theses.fr/2000LAROS050.
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Le travail qui est présenté dans cette thèse soulève la difficulté de sécher des produits thermoïoniques avec les procédés de déshydratation traditionnels. Ces procédés sont ici représentés par le séchage à l'air chaud, le séchage sous vide et la lyophilisation. Deux nouveaux procédés, inventés et mis au point au laboratoire Maitrise des technologies agro-industrielles, présentent une alternative aux procédés traditionnels. Ces deux nouveaux procédés, la détente instantanée contrôlée (DIC) et la déshydratation par détentes successives (DDS), sont basés sur une détente instantanée vers le vide qui provoque l'auto-vaporisation d'une partie de l'eau. La DIC utilise la vapeur pour monter en pression avant la détente. L’auto-vaporisation donne alors une structure poreuse au produit. Ce procédé s'insère dans un séchage par air chaud traditionnel ou peut être précédé d'un pressage. La DDS utilise de l'air comprimé et l'auto-vaporisation est moins intense que dans le cas de la DIC. La répétition des cycles DDS de montée en pression et détente permet la déshydratation complète le produit. L’étude consiste à comparer les procédés sur leur cinétique de séchage et sur la qualité du produit fini. Le poisson a été choisi comme produit de référence pour sa sensibilité au séchage et à la chaleur et pour les propriétés rhéologiques de sa chair. En premier lieu, les cinétiques de déshydratation des cinq procédés sont décrits et une méthode de caractérisation de la vitesse de séchage est définie. Dans le cas des nouveaux procédés DIC et DDS, l'effet des paramètres opératoires est étudié et souvent optimisé par plans d'expériences. Les nouveaux procédés montrent une grande rapidité pour le séchage du poisson. En effet, alors que le séchage convectif demande une trentaine d'heures pour déshydrater des cubes de poisson (et 17 h pour le séchage sous vide), la DDS ne prend que 7 h et le procédé pressage-DIC-air chaud environ 3,5 h. En outre, la DIC élimine les problèmes de transferts de matière liés à la croûte qui se forme lors des séchages par air chaud, sous vide et dans une moindre mesure, par DDS. Les différents procédés sont ensuite comparés sur le plan de la qualité finale des produits. Les mesures réalisées sur les produits DIC montrent leur grande qualité sur le plan fonctionnel : masse volumique importante, peu de micro-organismes et une très bonne réhydratation. Ces propriétés sont même supérieures à celles des produits lyophilisés. En revanche, la DDS se montre de qualité moyenne, proche de la qualité du séchage sous vide. Le séchage à l'air chaud présente d'importants défauts pour chacune des trois caractéristiques évaluées. Les produits sont également comparés sur le plan de la qualité organoleptique. Les profils sensoriels de couleur et de texture, confortés par des mesures instrumentales, montrent encore une fois que les poissons DIC, bien que moins appréciés par le consommateur, sont très proches des produits lyophilisés. Les produits DDS et séchés sous vide présentent encore une couleur et une texture moyenne mais qui restent supérieures à celles des produits séchés par air chaud. Enfin, les observations structurales et le recoupement de données permettent l'émission de certaines hypothèses sur le déroulement des phénomènes apparaissant au cours de la détente instantanée et en particulier au cours de la DIC. L'importance de l'hydrothermorhéologie du produit est mise en avant dans les phénomènes d'expansion. De la même manière l'observation microscopique de produits alimentaires expansés montre que les bulles et cavités apparaissent principalement au niveau cellulaire. La microrhéologie des constituants de l'aliment est donc également un des principaux facteurs de l'expansion.
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Bismuth, Anne. "Mycoses et parasitoses du tégument et des branchies chez les poissons d'aquarium dulçaquicoles." Paris 5, 1997. http://www.theses.fr/1997PA05P196.
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Dietz, Svetlana. "Flache Lösungen des Vlasov-Poisson-Systems." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964209292.
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Mayboroda, Svitlana. "The poisson problem on Lipschitz domains." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4133.
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Thesis (Ph.D.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 25, 2007) Vita. Includes bibliographical references.
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Dietz, Svetlana. "Flache Lösungen des Vlasov-Poisson-Systems." Diss., lmu, 2002. http://nbn-resolving.de/urn:nbn:de:bvb:19-14.
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Bäck, Viktor. "Localization of Multiscale Screened Poisson Equation." Thesis, Uppsala universitet, Algebra och geometri, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-180928.
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Gu, Kangxia. "Testing the rates of Poisson distribution." Ann Arbor, Mich. : ProQuest, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3213456.
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Thesis (Ph.D. in Statistical Science)--S.M.U.Title from PDF title page (viewed July 6, 2007). Source: Dissertation Abstracts International, Volume: 67-03, Section: B, page: 1504. Advisers: Hon Keung Tony Ng; William R. Schucany. Includes bibliographical references.
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Zwicknagl, Sebastian. "Equivariant Poisson algebras and their deformations /." view abstract or download file of text, 2006. http://proquest.umi.com/pqdweb?did=1280144671&sid=2&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2006.Typescript. Includes vita and abstract. "In this dissertation I investigate Poisson structures on symmetric and exterior algebras of modules over complex reductive Lie algebras. I use the results to study the braided symmetric and exterior algebras"--P. 1. Includes bibliographical references (leaves 150-152). Also available for download via the World Wide Web; free to University of Oregon users.
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Ahluwalia, Kanwardeep Singh. "Lie bialgebras and Poisson lie groups." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388758.
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Martino, Maurizio. "Symplectic reflection algebras and Poisson geometry." Thesis, University of Glasgow, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426614.
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Cruz, Ines Maria Bravo de Faria. "The local structure of Poisson manifolds." Thesis, University of Warwick, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309896.
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Faltinsen, Stig. "Geometric integration of lie-poisson systems." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621090.
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Sellner, Richard, Manfred M. Fischer, and Matthias Koch. "A Spatial Autoregressive Poisson Gravity Model." Wiley-Blackwell, 2013. http://dx.doi.org/10.1111/gean.12007.
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In this article, a Poisson gravity model is introduced that incorporates spatial dependence
of the explained variable without relying on restrictive distributional assumptions of the
underlying data-generating process. The model comprises a spatially filtered component
including the origin-, destination-, and origin-destination-specific variables and a spatial
residual variable that captures origin- and destination-based spatial autocorrelation. We
derive a two-stage nonlinear least-squares (NLS) estimator (2NLS) that is heteroscedasticity-
robust and, thus, controls for the problem of over- or underdispersion that often
is present in the empirical analysis of discrete data or, in the case of overdispersion, if
spatial autocorrelation is present. This estimator can be shown to have desirable properties
for different distributional assumptions, like the observed flows or (spatially) filtered component
being either Poisson or negative binomial. In our spatial autoregressive (SAR)
model specification, the resulting parameter estimates can be interpreted as the implied
total impact effects defined as the sum of direct and indirect spatial feedback effects. Monte
Carlo results indicate marginal finite sample biases in the mean and standard deviation of
the parameter estimates and convergence to the true parameter values as the sample size
increases. In addition, this article illustrates the model by analyzing patent citation flows
data across European regions. (authors' abstract)
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Zhang, Pumei. "Algebraic aspects of compatible poisson structures." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/10110.
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This thesis consists of three chapters. In Chapter one, we introduce some notions and definitions for basic concepts of the theory of integrable bi-Hamiltonian systems. Brief statements of several open problems related to our main results are also mentioned in this part. In Chapter two, we applied the so-called Jordan-Kronecker decomposition theorem to study algebraic properties of the pencil P generated by two constant compatible Poisson structures on a vector space. In particular, we study the linear automorphism group GP that preserves P. In classical symplectic geometry, many fundamental results are based on the symplectic group, which preserves the symplectic structure. Therefore in the theory of bi-Hamiltonian structures, we hope GP also plays a fundamental role. In Chapter three, we study one of the famous Poisson pencils which is sometimes called 'argument shift pencil'. This pencil is defined on the dual space g * of an arbitrary Lie algebra g. This pencil is generated by the Lie-Poisson bracket { , } and constant bracket { , }a for a ε g * . Thus we may apply the Jordan-Kronecker decomposition theorem to introduce the so-called Jordan-Kronecker invariants of a finite-dimensional Lie algebra g. These invariants can be understood as the algebraic type of the canonical Jordan-Kronecker form for the 'argument shift pencil' at a generic point. Jordan-Kronecker invariants are found for all low-dimensional Lie algebras (dim g ≤ 5) and can be used to construct the families of polynomials in bi-involution. The results are found to be useful in the discussion of the existence of a complete family of polynomials in bi-involution w.r.t. these two brackets { , } and { , }a.
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Pereira, Hemilhana Tolentina. "Estudo da distribuição de Poisson generalizada." reponame:Repositório Institucional da UnB, 2016. http://repositorio.unb.br/handle/10482/22839.
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Estatística, 2016.Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2017-03-02T16:05:18Z No. of bitstreams: 1 2016_HemilhanaTolentinaPereira.pdf: 1525219 bytes, checksum: 02fb8ee02557f6809a634f47ca36beec (MD5)
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Esta dissertação se dedica ao estudo e à revisão bibliográfica da distribuição de Poisson generalizada. Essa distribuição é uma alternativa aos modelos discretos que apresentam sobredispersão. A flexibilização do valor da variância em relação ao da média é devido ao acréscimo de um parâmetro à distribuição de Poisson. A distribuição de Poisson generalizada foi inicialmente introduzida como elemento da classe de distribuições Lagrangeanas. Neste trabalho é proposta uma parametrização em função da W de Lambert que permite relacioná-la à classe de distribuições de série de potência e, desse modo, valer-se das propriedades e das características dessa classe de distribuições. Além disso, serão apresentadas aplicações de diferentes áreas do conhecimento, métodos de estimação pontual e intervalar, testes de hipóteses e as funções do software R dedicadas a essa distribuição.
In this dissertation we present a review of the generalized Poisson distribution. This distribution is an alternative to allow over dispersion in discrete models. The flexibility of the value of the variance in relation to the average is due to the presence of an additional parameter with respect to the Poisson distribution. The generalized Poisson distribution was first introduced as an element of the class of Lagrangian distributions. In this work it is proposed a new parametrization in terms of the Lambert W function that allows us to relate it to the class of power series distributions and, therefore, to use well known properties and characteristics of this class. In addition, we will present applications from different areas of knowledge, inference methods for both point and interval estimation and hypotheses testing. Were also review some R packages which deal with this distribution.
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Saint-Germain, Michel. "Algebres de poisson et structures transverses." Paris 7, 1997. http://www.theses.fr/1997PA077150.
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Pour une algebre de lie nilpotente reelle, on considere une orbite coadjointe dans le dual de cette algebre. C'est une feuille symplectique de la structure de poisson de ce dual. L'algebre des fonctions regulieres sur l'orbite est une algebre de poisson-weyl. On a ainsi l'existence de fonctions regulieres sur l'orbite verifiant les relations de darboux. Le premier probleme etudie est celui du prolongement de ces fonctions par des fonctions sur le dual, verifiant encore les relations de darboux. On montre l'existence de relevements (homomorphismes d'algebres de poisson) de l'algebre de poisson-weyl precitee dans le complete de l'algebre symetrique de l'algebre de lie (complete pour la topologie associee a la filtration par les puissances de l'ideal attache a l'orbite). Il est muni naturellement d'une structure d'algebre de poisson. On rapproche ces resultats de ceux obtenus par alan weinstein. Le second probleme est l'etude du commutant de l'image de l'algebre de poisson-weyl attachee a l'orbite par un relevement. C'est une algebre de series formelles dont la classe d'isomorphie ne depend pas du relevement choisi. On compare cette algebre a celle donnee par la structure de poisson transverse a l'orbite, calculee par le theoreme de decomposition de alan weinstein ou la formule de p. A. M. Dirac. La methode des orbites associe a l'orbite coadjointe un ideal primitif de l'algebre enveloppante. Cette these est inspiree de l'etude faite par fokko du cloux du voisinage d'un tel ideal primitif. Celui est decrit par une algebre. Notre philosophie est que cette algebre est une quantification de la structure de poisson transverse a l'orbite.
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Ryan, Anne Garrett. "Surveillance of Poisson and Multinomial Processes." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/26549.
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As time passes, change occurs. With this change comes the need for surveillance. One may be a technician on an assembly line and in need of a surveillance technique to monitor the number of defective components produced. On the other hand, one may be an administrator of a hospital in need of surveillance measures to monitor the number of patient falls in the hospital or to monitor surgical outcomes to detect changes in surgical failure rates. A natural choice for on-going surveillance is the control chart; however, the chart must be constructed in a way that accommodates the situation at hand. Two scenarios involving attribute control charting are investigated here. The first scenario involves Poisson count data where the area of opportunity changes. A modified exponentially weighted moving average (EWMA) chart is proposed to accommodate the varying sample sizes. The performance of this method is compared with the performance for several competing control chart techniques and recommendations are made regarding the best preforming control chart method. This research is a result of joint work with Dr. William H. Woodall (Department of Statistics, Virginia Tech). The second scenario involves monitoring a process where items are classified into more than two categories and the results for these classifications are readily available. A multinomial cumulative sum (CUSUM) chart is proposed to monitor these types of situations. The multinomial CUSUM chart is evaluated through comparisons of performance with competing control chart methods. This research is a result of joint work with Mr. Lee J. Wells (Grado Department of Industrial and Systems Engineering, Virginia Tech) and Dr. William H. Woodall (Department of Statistics, Virginia Tech).Ph. D.
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Jin, Xiaodan. "Poisson Approximation to Image Sensor Noise." University of Dayton / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1292306911.
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Bailleul, Ismaël. "Frontière de Poisson d'une diffusion relativiste." Paris 11, 2006. http://www.theses.fr/2006PA112251.
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Cette thèse a pour objet l'étude du comportement asymptotique d'une diffusion définie sur l'espace/temps de minkowski. Le pendant analytique de ce problème est la détermination de l'ensemble des fonctions bornées du noyau d'un certain opérateur différentiel d'ordre 2. Utilisant des méthodes probabilistes (équations différentielles stochastiques, couplage), on donne une description explicite de cet ensemble de fonctions. On donne dans le meme temps une toute autre démonstration de ce résultat, dans l'esprit de travaux sur les marches aléatoires existant déjà. On montre par ailleurs comment la géométrie de l'espace se reflète sur le comportement asymptotique de la diffusion. En un sens, une trajectoire (aléatoire) typique finit par se comporter comme un trajectoire de lumièreIn this PhD thesis, we study the asymptotic behaviour of a diffusion defined on minkowski's spacetime. The analytic counterpart of this problem is to determine the set of bounded functions belonging to the kernel of some second order differential operator. Using probabilistic methods (stochastic differential equations, coupling), one gives an explicit description of this set of functions. In the same time, one give a completely different proof of this result, in the spirit of preexisting works on random walks on groups. Besides, one shows how the geometry of spacetime reflects on the asymptotic behaviour of the diffusion. In some sense, a typical (random) trajectory eventually behaves as a light ray
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Wang, Ling. "Homogeneity tests for several poisson populations." HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/909.
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van, de Ven Remy Julius. "Estimation in mixed Poisson regression models." Thesis, The University of Sydney, 1996. https://hdl.handle.net/2123/26822.
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This thesis considers estimation of the parameters associated with models for count data displaying over-dispersion relative to the Poisson distribution where the over-dispersion is modelled using mixing. It is divided into seven chapters with Chapters Two to Five specific to the over-dispersed Poisson problem whilst Chapter Seven, which uses results from Chapter Six, is more general. The motivation for some of this work was the modelling of repeat counts of the number of fibres contained on microscopic slides as obtained by asbestos fibre counters and the subsequent estimation of mean fibre concentrations and counter variability.
Chapter One introduces the above mentioned asbestos fibre problem and follows this with an overview of the thesis. In Chapter Two a model for repeated measures count data over-dispersed relative to the Poisson distribution appropriate to the asbestos problem is given. To accommodate the over-dispersion a Poisson random variable is compounded with a positive random variable with mean equal one and variance linked linearly, via a log function, to a set of covariates. Maximum likelihood estimators of the parameters are obtained for the case where the compounding distribution is gamma and extended quasi-likelihood parameter estimators are obtained when the compounding distribution is unspecified. These two sets of parameter estimators are then shown to be comparable in certain circumstances.
In Chapter Three a special case of the general model in Chapter Two with a gamma compounding distribution is considered. Here repeat counts for a “subject” are taken as independent Poisson random variables with constant mean. The means are then modelled as independent observations from a gamma distribution. Two sets of moment estimators for the parameters of the model are obtained and generalized variances of the limiting distribution of the moment estimators are compared with the corresponding quantity for the maximum likelihood estimators. Also in this chapter we derive asymptotic results that explain some of the erratic behaviour of the moment estimators.
Chapter Four considers the estimation of the shape parameter of the negative binomial distribution (NBD), this distribution being a special case of the model in Chapter Three. Here the results are given for a simulation study comparing four estimators for the shape parameter of the NBD distribution. Two criteria are used to compare the estimates obtained in the simulations, one being the traditional moment based criterion whilst the other is based on a new measure termed the “percentile measure”. This measure, based on the difference between the percentiles of the true and estimated distribution function, is argued to be more appropriate in many cases.
In Chapter Five we continue studying the NBD and obtain some quantile related results. First we obtain bounds for the median in terms of the mean that are improvements on the bounds obtained by Payton, Young and Young (1989). Second we obtain percentile related bounds for the mean and use this to obtain a robust estimator for the mean of the NBD when the shape parameter is known.
The remaining two chapters are devoted to robust estimation in (generalized) linear mixed models. In Chapter Six a modification to the Fellner (1991) procedure for robustly estimating variance components in normal linear mixed models is proposed and studied. Also given is a robust moment based method. These robust methods are then applied in Chapter Seven to the generalized linear mixed model to obtain robust parameter estimators and the behaviour of these new estimators is studied via a simulation study.
From this simulation study in Chapter Seven it is concluded that the extension to generalized linear mixed models of the modification to Fellner’s method has merit.
There should though be scope for improvement in the method and this could be a subject for further research. In particular, a possible mechanism for achieving an improvement would be to have more robust starting values for the variance components in the iterative procedure proposed. One solution would be to develop quantile based variance components estimates in the generalized linear mixed model and to use these as starting values.
Another project for further research would be to obtain expressions for the variances of the fixed effects estimates for the linear mixed model obtained using the Fellner (1991) method. This would necessarily be an asymptotic result and of interest in its own right. However, once this was available the modified Fellner method of Chapter Six and its extension to generalized linear mixed models given in Chapter Seven could be improved. This is the case as the modification to Fellner’s method given in Chapter Six currently uses for these values the variances of the BLUP estimates of the fixed effects.
Finally, an alternative robust estimation procedure based on the results of Windham (1995) could be another subject for further research. That paper, which assumes the data are independent and identically distributed (iid), proposes an estimation procedure that weights datum according to the value of the estimated likelihood at that datum point. The procedure seems to have merit based on the examples considered in Windham’s paper, which include some skewed distributions (e.g. gamma). Further research could consider extending the results to the non it'd
case, in particular data from generalized linear mixed model problems. It may be possible using such a procedure in generalized linear mixed model cases to reduce some of the bias that is inherent in procedures based on Winsorization.
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Magnano, Guido. "Poisson-Nijenhuis Structures and Sato Hierarchy." Doctoral thesis, SISSA, 1991. http://hdl.handle.net/20.500.11767/4437.
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The thesis is organized in three distinct parts. The first part ( § 1 and §2) is purely
expository. After a brief introduction to the basic ideas of the bi-Hamiltonian approach
to integrable systems in §1, in §2 the bi-Hamiltonian factorization of Sato's equations is
described as explicitly as possible. This section collects the "experimental facts" which
we aim to explain in the following part of the thesis. In §2 we also introduce and discuss
different representations of the Sato hierarchy, as families of integro-differential equations
in two space variables and in a finite number of fields, which we call Sato-Gel'fand-Dikii
hierarchies. The simplest representation of this type coincides with the well-known KP
hierarchy, while the other representations do not appear, to oμr knowledge, in the previous
literature. The second part of the thesis includes §3, §4 and §5 and represents the theoretical core
of this work. The main result (§4) is the construction of the Poisson-Nijenhuis structures
already mentioned; in §5 we introduce the Kac-Moody algebra of Hamiltonian vector fields,
and we show that these vector fields admit a Lax representation. The only arbitrary point
in the construction is the choice of a Lie-algebra cocycle corresponding to the affine part
of the Lie-Poisson brackets: both the Kac-Moody algebra of bi-Hamiltonian vector fields
and its Lax representation are completely determined by that cocycle.
The third and final part is devoted to the formal application of the abstract framework
to algebras of pseudodifferential operators. In §6 the Gel'fand-Dikii and the Sato-Gel'fandDikii
hierarchies are obtained as reductions (on different affine subspaces) of the dynamical
systems previously obtained, for finite n, while the Sato hierarchy is recovered in §7 as a
generalization of the same construction to the case n = oo.
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Eude, Thierry. "Contribution à l'étude du poisson-pierre." Paris 5, 1988. http://www.theses.fr/1988PA05P085.
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AMBROSO, ANNALISA. "Sur la resolution des problemes de vlasov-poisson et d'euler-poisson. Applications a la physique des plasmas." Palaiseau, Ecole polytechnique, 2000. http://www.theses.fr/2000EPXX0048.
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Mes travaux de these se focalisent principalement sur l'etude de quelque dispositif a plasma electrostatiques, qui fonctionnent en regime stationnaire. D'une part, je me suis interessee a l'analyse des phenomenes d'apparition de couches limites dans les diodes a plasma dont le modele peut etre reduit a la resolution d'un probleme de perturbation singuliere pour une equation elliptique nonlineaire portant sur le potentiel electrique. On a demontre l'existence de solutions a ce probleme, en particulier, on a montre la presence de couches limites et de couches libres que l'on a etudie a l'aide d'une analyse asymptotique complete. D'autre part, j'ai analyse la non-linearite due au couplage entre le mouvement de particules de signe oppose et le champ electrique auto-consistant et, en particulier, aux phenomenes de piegeage des particules. On a etudie un systeme de vlasov-poisson stationnaire en presence d'un terme source. Ce probleme est issu d'un modele pour un faisceau d'ions se propageant en presence d'un gaz residuel. Notre but a ete de montrer qu'il existe des situations physiques pour lesquelles le probleme n'admet pas de solution et de proposer des modeles differents pour remedier a cette difficulte. En premier lieu, on a pris en compte les collisions et nous avons etabli un theoreme d'existence pour une equation de vlasov lineaire incluant un terme de diffusion. D'un autre cote, nous avons considere un modele dit du gap qui permet d'obtenir un resultat d'existence pour le probleme nonlineaire complet.
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Bernis, Laurent. "Etude mathématique d'équations aux dérivées partielles issues de la physique des plasmas (Vlasov-Poisson et Vlasov-Poisson-Boltzmann)." Orléans, 2006. http://www.theses.fr/2006ORLE2040.
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Les deux premiers chapitres de ce travail sont consacrés à l’étude de l’équation de Vlasov-Poisson dans le cadre de la modélisation d’un faisceau de particules chargées. Nous établissons l’existence et l’unicité de solutions stationnaires, qui sont des fonctions fixées de l’énergie et du moment angulaire. Nous recourons d’abord à une méthode variationnelle, puis à une méthode constructive de tir. Le troisième chapitre étudie, pour des solutions de l’équation de Vlasov-Poisson-Boltzmann, la propagation des singularités locales de la distribution initiale.