Results 31 to 40 of about 2,830 (310)

Degenerate singular parabolic problems with natural growth [PDF]

Opuscula Mathematica
In this paper, we study the existence and regularity results for nonlinear singular parabolic problems with a natural growth gradient term \[\begin{cases}\frac{\partial u}{\partial t}-\operatorname{div}((a(x,t)+u^{q})|\nabla u|^{p-2}\nabla u)+d(x,t)\frac{
Mounim El Ouardy, Youssef El Hadfi, Abdelaaziz Sbai   +2 more
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Local Calderón-Zygmund estimates for parabolic equations in weighted Lebesgue spaces

Mathematics in Engineering, 2023
We prove local Calderón-Zygmund type estimates for the gradient of weak solutions to degenerate or singular parabolic equations of $ p $-Laplacian type with $ p > \frac{2n}{n+2} $ in weighted Lebesgue spaces $ L^q_w $.
Mikyoung Lee, Jihoon Ok
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Optimal Control Problems of a Class of Nonlinear Degenerate Parabolic Equations

Mathematics
The optimal control problems of degenerate parabolic equations have many applications in economics, physics, climatology, and so on. Motivated by the applications, we consider the optimal control problems of a class of nonlinear degenerate parabolic ...
Yang Na, Tianjiao Men, Runmei Du, Yingjie Zhu   +3 more
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Expansion of positivity to a class of doubly nonlinear parabolic equations

Electronic Journal of Qualitative Theory of Differential Equations, 2022
We establish the expansion of positivity of the nonnegative, local, weak solutions to the class of doubly nonlinear parabolic equations $$\partial_t (u^{q}) -\operatorname{div}{(|D u|^{p-2} D u)}=0, \qquad\ p>1 \ \text{and} \ q>0$$ considering ...
Eurica Henriques
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Difference schemes for degenerate parabolic equations [PDF]

Mathematics of Computation, 1986
Diagonal dominant implicit-difference schemes approximating a porous media type class of multidimensional nonlinear equations are shown to generate semigroups in an approximate L 1 {L^1} -space, and the rate of convergence to the semigroup solution in L 1
openaire   +1 more source

Null controllability of degenerate parabolic operators with drift

Networks and Heterogeneous Media, 2007
We give null controllability results for some degenerate parabolic equations in non divergence form with a drift term in one space dimension. In particular, the coefficient of the second order term may degenerate at the extreme points of the space domain.
Piermarco Cannarsa, Genni Fragnelli, Dario Rocchetti   +2 more
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Impulsive Quenching for Degenerate Parabolic Equations

Journal of Mathematical Analysis and Applications, 1996
An impulsive problem for a singular degenerate parabolic equation is studied. Sufficient conditions for the existence of a unique critical length are given. The critical length \(a^*\) is the length of the space interval such that the solution with zero initial and boundary data quenches for intervals larger than \(a^*\) but it exists globally for ...
Chan, C.Y., Kong, P.C.
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NULL CONTROLLABILITY OF DEGENERATE NONAUTONOMOUS PARABOLIC EQUATIONS [PDF]

Facta Universitatis, Series: Mathematics and Informatics, 2019
In this paper we are interested in the study of the null controllability for the one dimensional degenerate non autonomous parabolic equation$$u_{t}-M(t)(a(x)u_{x})_{x}=h\chi_{\omega},\qquad  (x,t)\in Q=(0,1)\times(0,T),$$ where $\omega=(x_{1},x_{2})$ is asmall nonempty open subset in $(0,1)$, $h\in L^{2}(\omega\times(0,T))$, the diffusion coefficients
Benaissa, Abbes, Mezadek, Abdelatif Kainane, Maniar, Lahcen   +2 more
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Singularly perturbed periodic parabolic equations with alternating boundary layer type solutions

Abstract and Applied Analysis, 2006
We consider a class of singularly perturbed parabolic equations for which the degenerate equations obtained by setting the small parameter equal to zero are algebraic equations that have several roots.
Adelaida B. Vasil'eva, Leonid V. Kalachev   +1 more
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Fundamental solutions for degenerate parabolic equations [PDF]

Acta Mathematica, 1974
This chapter explains the construction of a candidate for a fundamental solution and the existence, smoothness, and certain bounds for a fundamental solution Γ. The underlying assumptions were that ( a ij , ( x )) is uniformly positive definite and a ij , b i are bounded and uniformly Holder continuous. The chapter presents a proof of how if a ij ,
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