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Now showing items 21-30 of 75
Geometric invariants of groups and property R-infty
(Universidade Federal de São Carlos, 2022-01-05)
In this thesis we study property R_\infty for some classes of finitely generated groups by the use of the BNS invariant \Sigma^1 and some other geometric tools. In the combinatorial chapters of the work (4, 5, 6, 10 and ...
Um estudo de valorizações transcendentes e algébricas via polinômios-chaves e pares minimais
(Universidade Federal de São Carlos, 2022-02-24)
The main goal of this work is to study transcendental valuations and algebraic valuations. To achieve this, we use some of the main objects in Valuation Theory, such as key polynomials, truncations and minimal pairs. These ...
Estabilidade, instabilidade e fenômenos de concentração em equações de reação e difusão: uma abordagem geométrica
(Universidade Federal de São Carlos, 2022-12-07)
In this work, we adress the study of stability of a reaction-difusion equation in two domains: in a family of surfaces of revolution without boundary and in a bounded open interval whose diffusion function vanishes at a ...
Não unicidade para uma classe de operadores do tipo parabólico
(Universidade Federal de São Carlos, 2022-01-18)
In this thesis we consider the non-uniqueness for a class of parabolic operators. We will
prove that for certain real analytic perturbation of the Heat Operator there is a non unique
solution for the Initial Value Problem.
Soluções positivas para equações elípticas com operadores fracionários
(Universidade Federal de São Carlos, 2022-03-18)
In this work, we present results of existence, non-existence and multiplicity of positive
solutions to elliptic problems involving the fractional p-Laplacian operator and the
fractional Laplacian in the critical case, ...
O número de Bruce-Roberts sobre uma ICIS
(Universidade Federal de São Carlos, 2022-01-19)
In this work we study the relations between the Bruce-Roberts number, $\mu_{BR}(f,X)$, the relative Bruce-Roberts, $\mu_{BR}^{-}(f,X)$, of a function germ $f\in\mathcal{O}_{n}$ over an ICIS, $(X,0)\subset (\C^{n},0)$, and ...
Polynomial Weingarten surfaces of tubular type
(Universidade Federal de São Carlos, 2022-04-04)
This work seeks to contribute to the classification of Weingarten surfaces. More precisely, it fully classifies three families of surfaces (named tubular, cyclic and canal surfaces) in a tridimensional space form (Euclidean, ...
Laplaciano de Dirichlet em faixas com cantos
(Universidade Federal de São Carlos, 2022-02-24)
Let $\Omega_\theta$ be an unbounded V-shaped set of the plane $\mathbb{R}^2$ , that is, a strip with a corner, and consider $ - \Delta^{D}_{\Omega_\theta}$ the Dirichlet Laplacian in $ \Omega_\theta$. In this work, we will ...
A álgebra graduada associada a uma valorização
(Universidade Federal de São Carlos, 2021-11-30)
We begin this work with a study of the graded algebra associated to a valuation $\nu: K \longrightarrow \Gamma_{\infty}$. We verify that in the cases where the value group is free or the residue field is closed by radicals, ...
Hipoelipticidade global analítica e Gevrey de sublaplacianos sob condições Diofantinas
(Universidade Federal de São Carlos, 2022-09-22)
In this dissertation we consider the problem of global Gevrey regularity for a class of partial differential
operators in the form of a sum of squares of vector fields and we show that these operators are
globally Gevrey ...