Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Ingram, Mary Ann; Committee Member: Blough, Douglas; Committee Member: Sivakumar, Raghupathy. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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Among all stochastic processes with independent increments, essentially only Brownian motion and Poisson process have a chaotic representation property. In the case of a Levy process, several approaches have been proposed in order to construct an orthogonal decomposition of the corresponding L2-space. In this dissertation, we deal with orthogonal (chaotic) decompositions for generalized processes with independent values. We do not suppose stationarity of the process, as a result the Levy measure of the process depends on points of the space. We first construct, in Chapter 3, a unitary isomorphism between a certain symmetric Fock space and the space L2 (D',mu). Here D' is a co-nuclear space of generalized functions (distributions), and mu is a generalized stochastic process with independent values. This isomorphism is constructed by employing the projection spectral theorem for an (uncountable) family of commuting self-adjoint operators. We next derive, in Chapter 4, a counterpart of the Nualart Schoutens decomposition for generalized stochastic process with independent values. Our results here extend those in the papers of Nualart Schoutens and Lytvynov. In Chapter 5, we construct an orthogonal decomposition of the space L2 (D',mu) in terms of orthogonal polynomials on D'. We observe a deep relation between this decomposition and the results of the two previous chapters. Finally, in Chapter 6, we briefly discuss the situation of the generalized stochastic processes of Meixner's type.

Orientador: Eliana Xavier Linhares de Andrade / Banca: Sérgio Antonio Tozoni / Banca: Dimitar Kolev Dimitrov / Resumo: O principal objetivo deste trabalho é estudar um problema de eletrostática geral que envolve ambos, um campo externo e restrições sobre cargas livres. Foram fornecidas condições necessárias e suficientes para o mínimo da energia em termos de soluções polinomiais de uma equação diferencial de Lamé modificada. Além disso, foram dadas novas demonstrações, mais simples, de resultados clássicos de Stieltjes e Szego. Finalmente, foi obtida uma interpretação eletrostática para os zeros dos polinômios comumente chamados de Hermite-Laurent. / Abstract: A general electrostatic problem which involves both an external field and restrictions on the free charges is studied. Necessary and sufficient conditions for the minimum of the energy are furnished in terms of polynomial solutions of a modified Lamé differential equation. New simplified proofs of classical results of Sitieltjes and Szego are given. An electrostatic interpretation of the so-called Hermite-Laurent polynomials is obtained. / Mestre

Much of weighted polynomial approximation originated with the famous Bernstein qualitative approximation problem of 1910/11. The classical Bernstein approximation problem seeks conditions on the weight functions \V such that the set of functions {W(x)Xn};;"=l is fundamental in the class of suitably weighted continuous functions on R, vanishing at infinity. Many people worked on the problem for at least 40 years. Here we present a short survey of techniques and methods used to prove Markov and Bernstein inequalities as they underlie much of weighted polynomial approximation. Thereafter, we survey classical techniques used to prove Jackson theorems in the unweighted setting. But first we start, by reviewing some elementary facts about orthogonal polynomials and the corresponding weight function on the real line. Finally we look at one of the processes (If approximation, the Lagrange interpolation and present the most recent results concerning mean convergence of Lagrange interpolation for Freud and Erdos weights. / Andrew Chakane 2018

MSc., Faculty of Science, University of the Witwatersrand, 2011 / We try to develop a collective field theory of single matrix models by using the formalism of Jevicki and Sakita in [1], with Schur polynomials as our collective fields. Field operators and the relation for the change of variables required to obtain the collective field Hamiltonian are found using group representation theory.

Made available in DSpace on 2014-06-11T19:26:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-01-20Bitstream added on 2014-06-13T20:55:41Z : No. of bitstreams: 1 campetti_mh_me_sjrp.pdf: 574554 bytes, checksum: a27f7403e37f640c1f02b66b9632ca90 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo deste trabalho é fazer um estudo das propriedades de duas sequências de polinômios, {Pϕ0 n }∞ n=0 e {Pϕ1 n }∞ n=0, ortogonais com relação, respectivamente, às medidas dϕ0 e dϕ1, relacionadas entre si, e das propriedades de duas sequências de polinômios L-ortogonais, {Bψ0 n }∞ n=0 e {Bψ1 n }∞ n=0, quando as medidas associadas, dψ0 e dψ1, est˜ao tamb´em relacionadas. Para os polinômios ortogonais, foram considerados dois casos: polinômios ortogonais associados a medidas simétricas relacionadas por dϕ1(x) = c 1 + qx2 dϕ0(x) e polinˆomios ortogonais associados a medidas relacionadas por (x − q) dϕ1(x) = c dϕ0(x). Como exemplo, os resultados foram aplicados no estudo de polinˆomios ortogonais de Sobolev associados a medidas simétricas como os de Gegenbauer e Hermite, e medidas não simétricas como as de Jacobi e Laguerre. Para os polinômios L-ortogonais, considerou-se o estudo de duas sequências de polinômios associados a medidas positivas fortes dψ0 e dψ1 relacionadas por (z − κ) dψ1(z) = c dψ0(z). Como consequência dessas propriedades, algoritmos para gerar qualquer um dos pares de coeficientes das relações de recorrência, {αψ0 n , βψ0 n } ou {αψ1 n , βψ1 n }, dado o outro, foram dados. / The main purpose of this work is to study some properties of two sequences of polynomials, {Pϕ0 n }∞ n=0 and {Pϕ1 n }∞ n=0, orthogonal, respectively, with respect to the related measures dϕ0 and dϕ1, and properties of two sequences of L-orthogonal polynomials, {Bψ0 n }∞ n=0 and {Bψ1 n }∞ n=0, when the associated measures, dψ0 and dψ1, are also related. For the orthogonal polynomials, we considered two cases: orthogonal polynomials associated with symmetric measures related to each other by dϕ1(x) = c 1 + qx2 dϕ0(x) and orthogonal polynomials associated with measures related by (x − q) dϕ1(x) = c dϕ0(x). As examples, the results are applied to obtain informations regarding Sobolev orthogonal polynomials associated with symmetric measures as Gegenbauer and Hermite measures, and non-symmetrical measures such as Jacobi and Laguerre measures. For the L-orthogonal polynomials, we considered the study of two sequences of polynomials associated with strong positive measures dψ0 and dψ1 and related to each other by (z −κ) dψ1(z) = c dψ0(z). As a consequence of these properties, algorithms to generate any pair of coefficients of the recurrence relations, {αψ0 n , βψ0 n } or {αψ1 n , βψ1 n }, given the other, were given.

Orientador: Eliana Xavier Linhares de Andrade / Banca: Fernando Akira Kurokawa / Banca: Cleonice Fátima Bracciali / Resumo: O objetivo deste trabalho é fazer um estudo das propriedades de duas sequências de polinômios, {Pϕ0 n }∞ n=0 e {Pϕ1 n }∞ n=0, ortogonais com relação, respectivamente, às medidas dϕ0 e dϕ1, relacionadas entre si, e das propriedades de duas sequências de polinômios L-ortogonais, {Bψ0 n }∞ n=0 e {Bψ1 n }∞ n=0, quando as medidas associadas, dψ0 e dψ1, est˜ao tamb'em relacionadas. Para os polinômios ortogonais, foram considerados dois casos: polinômios ortogonais associados a medidas simétricas relacionadas por dϕ1(x) = c 1 + qx2 dϕ0(x) e polinˆomios ortogonais associados a medidas relacionadas por (x − q) dϕ1(x) = c dϕ0(x). Como exemplo, os resultados foram aplicados no estudo de polinˆomios ortogonais de Sobolev associados a medidas simétricas como os de Gegenbauer e Hermite, e medidas não simétricas como as de Jacobi e Laguerre. Para os polinômios L-ortogonais, considerou-se o estudo de duas sequências de polinômios associados a medidas positivas fortes dψ0 e dψ1 relacionadas por (z − κ) dψ1(z) = c dψ0(z). Como consequência dessas propriedades, algoritmos para gerar qualquer um dos pares de coeficientes das relações de recorrência, {αψ0 n , βψ0 n } ou {αψ1 n , βψ1 n }, dado o outro, foram dados. / Abstract: The main purpose of this work is to study some properties of two sequences of polynomials, {Pϕ0 n }∞ n=0 and {Pϕ1 n }∞ n=0, orthogonal, respectively, with respect to the related measures dϕ0 and dϕ1, and properties of two sequences of L-orthogonal polynomials, {Bψ0 n }∞ n=0 and {Bψ1 n }∞ n=0, when the associated measures, dψ0 and dψ1, are also related. For the orthogonal polynomials, we considered two cases: orthogonal polynomials associated with symmetric measures related to each other by dϕ1(x) = c 1 + qx2 dϕ0(x) and orthogonal polynomials associated with measures related by (x − q) dϕ1(x) = c dϕ0(x). As examples, the results are applied to obtain informations regarding Sobolev orthogonal polynomials associated with symmetric measures as Gegenbauer and Hermite measures, and non-symmetrical measures such as Jacobi and Laguerre measures. For the L-orthogonal polynomials, we considered the study of two sequences of polynomials associated with strong positive measures dψ0 and dψ1 and related to each other by (z −κ) dψ1(z) = c dψ0(z). As a consequence of these properties, algorithms to generate any pair of coefficients of the recurrence relations, {αψ0 n , βψ0 n } or {αψ1 n , βψ1 n }, given the other, were given. / Mestre