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Esistenza e unicità degli stati fondamentali per equazioni ellittiche quasilineari

Bruno Franchi, Ermanno Lanconelli, James Serrin (1985)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

In this paper we describe some existence and uniqueness theorems for radial ground states of a class of quasilinear elliptic equations. In particular, the mean curvature operator and the degenerate Laplace operator are considered.

Estimates and computations for melting and solidification problems

James M. Greenberg (2001)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

In this paper we focus on melting and solidification processes described by phase-field models and obtain rigorous estimates for such processes. These estimates are derived in Section 2 and guarantee the convergence of solutions to non-constant equilibrium patterns. The most basic results conclude with the inequality (E2.31). The estimates in the remainder of Section 2 illustrate what obtains if the initial data is progressively more regular and may be omitted on first reading. We also present some...

Estimates and Computations for Melting and Solidification Problems

James M. Greenberg (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

In this paper we focus on melting and solidification processes described by phase-field models and obtain rigorous estimates for such processes. These estimates are derived in Section 2 and guarantee the convergence of solutions to non-constant equilibrium patterns. The most basic results conclude with the inequality (E2.31). The estimates in the remainder of Section 2 illustrate what obtains if the initial data is progressively more regular and may be omitted on first reading. We also present...

Estimates for Principal Lyapunov Exponents: A Survey

Janusz Mierczyński (2014)

Nonautonomous Dynamical Systems

This is a survey of known results on estimating the principal Lyapunov exponent of a timedependent linear differential equation possessing some monotonicity properties. Equations considered are mainly strongly cooperative systems of ordinary differential equations and parabolic partial differential equations of second order. The estimates are given either in terms of the principal (dominant) eigenvalue of some derived time-independent equation or in terms of the parameters of the equation itself....

Estimates near the boundary for second order derivatives of solutions of the Dirichlet problem for the biharmonic equation

Vladimir A. Kondratiev, Olga A. Oleinik (1986)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

Per ogni soluzione della (1) nel dominio limitato Ω ,, appartenente a H 0 2 ( Ω ) e soddisfacente le condizioni (2), si dimostra la maggiorazione (5), valida nell'intorno di ogni punto x 0 del contorno; si consente a Ω di essere singolare in x 0 .

Etude asymptotique de la jonction d'un massif tridimensionnel et d'une tige élancée en flexion.

B. Mampassi (1994)

Revista Matemática de la Universidad Complutense de Madrid

We are very interested with asymptotic problems for the system of elasticity involving small parameters in the description of the domain where the solutions is searched. The corresponding asymptotic expansions have different forms in the various between them. More precisely, our work is concerned with a precise description of the deformation and the stress fields at the junction of an elastic three-dimensional body and a cylinder. The corresponding small parameter is the diameter of the cylinder....

Evolution in a migrating population model

Włodzimierz Bąk, Tadeusz Nadzieja (2012)

Applicationes Mathematicae

We consider a model of migrating population occupying a compact domain Ω in the plane. We assume the Malthusian growth of the population at each point x ∈ Ω and that the mobility of individuals depends on x ∈ Ω. The evolution of the probability density u(x,t) that a randomly chosen individual occupies x ∈ Ω at time t is described by the nonlocal linear equation u t = Ω φ ( y ) u ( y , t ) d y - φ ( x ) u ( x , t ) , where φ(x) is a given function characterizing the mobility of individuals living at x. We show that the asymptotic behaviour of u(x,t)...

Evolution of convex entire graphs by curvature flows

Roberta Alessandroni, Carlo Sinestrari (2015)

Geometric Flows

We consider the evolution of an entire convex graph in euclidean space with speed given by a symmetric function of the principal curvatures. Under suitable assumptions on the speed and on the initial data, we prove that the solution exists for all times and it remains a graph. In addition, after appropriate rescaling, it converges to a homothetically expanding solution of the flow. In this way, we extend to a class of nonlinear speeds the well known results of Ecker and Huisken for the mean curvature...

Exact controllability of the wave equation with mixed boundary condition and time-dependent coefficients

M. M. Cavalcanti (1999)

Archivum Mathematicum

In this paper we study the boundary exact controllability for the equation t α ( t ) y t - j = 1 n x j β ( t ) a ( x ) y x j = 0 in Ω × ( 0 , T ) , when the control action is of Dirichlet-Neumann form and Ω is a bounded domain in R n . The result is obtained by applying the HUM (Hilbert Uniqueness Method) due to J. L. Lions.

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