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Hipoeliticidade global e vetores simultaneamente aproximáveis.
(Universidade Federal de São Carlos, 2003-08-11)
A necessary and sufficient condition is given for a sum of squares operator to be globally hypoelliptic. This condition is expressed in terms of Diophatine approximation properties of the coefficients. The proof of the ...
Sistemas elípticos com pesos envolvendo o expoente crítico de Hardy-Sobolev
(Universidade Federal de São Carlos, 2007-11-20)
In this work, we will study the existence and nonexistence of positive weak solutions
for two classes of elliptic systems with weights. The first class will involve nonlinearities of
the type positone and semipositone. We ...
Resolubilidade global para operadores diferenciais parciais reais de ordem um
(Universidade Federal de São Carlos, 2006-06-30)
The present work study the global solvability of first order real linear partial diferential
operators when the principal part has precisely one equilibrium point.
Moreover, examples and counterexamples are presented.
Estabilidade dinâmica para sistemas quânticos dependentes do tempo
(Universidade Federal de São Carlos, 2006-10-16)
We study if a time-dependent system is either dynamically stable or unstable,
i.e., if the expected value of a positive and discrete observable is a bounded
function of time or not. Initially we consider topological ...
Existência de múltiplas soluções para classes de problemas elípticos com função peso mudando de sinal em domínios ilimitados
(Universidade Federal de São Carlos, 2009-03-20)
The aim of this work is to give some suficient conditions for the existence and multiplicity of the solutions for a class of elliptic problems with sign-changing weight function in unbounded domains, using for this variational ...
Existência de variedade invariante e atrator para a equação ut = uxx + f(u)
(Universidade Federal de São Carlos, 2007-03-26)
In this work we study the differential equation
ut = uxx+ f (u); 0 6 x 6 1; t > 0
with homogeneous Dirichlet boundary conditions and f 2C1(R;R) lipschitz and bounded globally
and satisfying the following conditions:
...
Extensões de distribuições quase-homogêneas
(Universidade Federal de São Carlos, 2007-02-02)
In this dissertation the author proves two results of extensions for IRn of distribution solutions in IRn{0} of the operator Lλ,a = n ∑ i=1 λixi@xi − a, with λ = (λ1, . . . , λn) E Rn ...
G-variedades riemannianas como hipersuperfícies de formas espaciais
(Universidade Federal de São Carlos, 2006-02-20)
(See full text for download)
It is proved that an isometric immersion f: Mn ! Qn+1
c of a compact Riemannian mani-fold of dimension n ¸ 3 into a space form of dimension n + 1 is equivariant with respect
to a Lie group ...
Sincronização e continuidade em um problema parabólico governado pelo p-Laplaciano
(Universidade Federal de São Carlos, 2009-02-16)
In this work we study a reaction diffusion problem governed by the p-laplacian with p > 2 and we analyze properties of the continuity of the set of equilibria with respect to the diffusion parameter. We also consider coupled ...
Movimento de interface para duas equações de reação-difusão
(Universidade Federal de São Carlos, 2007-02-26)
In this work, following [15], we will use the technique of matched asymptotic
expansions to study the movement of interface for the solutions of an advection-reaction-
difuusion equations and the equation of reaction-difusion ...