3125763 documents found, page 8452 of 312577
Estudo de uma classe de equações elípticas semilineares em Rn
Santos, Tatiane CarvalhoIn this work we study the semilinear elliptic equation -u + jujp + f (x) = 0 in Rn, where n - 3, p > n-(n - - 2) and f is a Hölder continuous function. Assuming a growth condition on f at in nity we discuss the existence of classical solution. Furthermore, we prove a comparison principle and as a consequence we obtain results of non-existence and uniqueness of classical solution in a certain class of functions....
Reduções em Família e Multiplicidades Mistas
Sarria, Luis Alberto AlbaLet (R,m) be a Noetherian local ring. Mixed multiplicities of finitely many m-primary ideals were first defined by J. Risler and B. Teissier in [Teissier] and they proved that these could be described as the usual Hilbert-Samuel multiplicity of the ideal generated by an appropriated superficial sequence. This result was later generalized by D. Rees in [Rees], who first introduced the notion of joint reduction f...
Um Sistema Hiperbólico Acoplado Envolvendo o Operador p-Laplaciano
Carvalho, Pitágoras Pinheiro deOur goal in this work is to study the existence of weak solutions for the coupled system, in the form: 8> ><>>: u00 + Au --- u0 + --jvj-+2 + jzj-+2-juj- u = f1 v00 + Av -- -v0 + --juj-+2 + jzj-+2-jvj- v = f2 z00 + Az -- -z0 + --juj-+2 + jvj-+2-jzj- z = f3 ; em Q; com, Q = (0; T)- with, Q = (0; T) - where (0; T) is a real line, an open, limited and regular of R3; and - = 3 Xj=1 @2 @x2 j is the Laplacian operator...
Controlabilidade Finito-Aproximada e Nula para a Equação do Calor Semilinear
Pires, Elielson MendesWe consider the semilinear heat equation involving gradient terms in a bounded domain of Rn. It is assumed the non-linearity is globally Lipschitz. We prove that the system is approximately controllable when the control acts on a bounded subset of the domain. The proof uses a variant of a classical fixed point method and is a simpler alternative to the earlier proof existing in the literature by means of the pe...
Representação Tipo Weierstrass para Superfícies Imersas em Espaços de Heisenberg.
Santos Júnior, Valdecir Alves dosIn this work we obtain Weierstrass-type representations for immersed surfaces in Heisenberg space, endowed with a left-invariant metric. We will consider the Riemannian and Lorentzian case. We will define two complex functions (spinors) satisfying a linear Dirac-type equation, obtaining thus a representation for immersed surfaces with prescribed mean curvature. The same will enable us write a representation of ...
Idealizadores tangenciais e derivações de Anéis de Stanley-Reisner
Oliveira, Ana Karine Rodrigues deThe present dissertation furnishes a detailed study about modules of logarithmic derivations, here dubbed tangential idealizers, and some of their main features. Initially, several comparisons between such modules are investigated starting from sufficiently related ideals, motivated by a previous study due to Kaplansky as well as by their close relationship with the classical theory of differential ideals of Se...
Multiplicidade de soluções positivas para algumas classes de problemas elíptico...
Oliveira, Elisânia Santana deIn this work, we prove the existence and multiplicity of positive weak solutions for some classes of elliptic problems in plane involving exponential growth of the Trudinger-Moser type with Neumann boundary condition. To do this, we use the method of sub and supersolution in combination with variational methods and the maximum principle.; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES; Nest...
Sobre a Fibra Especial de Ideais
Silva, Tarciana Maria Santos daIn this dissertation, we study Cohen-Macaulay and Gorenstein properties of the fiber cone of an ideal I of d-dimensional Cohen-Macaulay local ring (R,m).We also obtain a formula to express the multiplicity of the fiber cone of a m-primary ideal I in terms of mixed multiplicity ed−1(m|I) and superficial elements. As a consequence, we have that the Cohen-Macaulay properties of the fiber cone of I, with minimal mi...
Controlabilidade exata local para as trajetórias de um sistema não-linear acopl...
Souza, Diego Araujo deThis dissertation is devoted to prove the local exact controllability to the trajectories for a coupled system, of the Boussinesq kind. In the state system, the unknowns are the velocity field and pressure of the uid (y; p), the temperature (-) and an additional variable c that can be viewed as the concentration of a contaminant solute. We prove several results, that essentially show that it is sufficient to ac...
Sobre um Sistema do tipo Schrödinger-Poisson
Batista, Alex de MouraIn this dissertation, we study the existence of two types of non-negative weak solutions for a class of problems of Schrodinger-Poisson type. This kind of problem models, for example, several physical phenomena in quantum mechanics. Initially, by minimization arguments, Splitting Lemma and the Variational Principle of Ekeland we find a weak solution that minimizes the minimum energy level associated to the vari...