Page 1

Displaying 1 – 15 of 15

Showing per page

Generating singularities of solutions of quasilinear elliptic equations using Wolff’s potential

Darko Žubrinić (2003)

Czechoslovak Mathematical Journal

We consider a quasilinear elliptic problem whose left-hand side is a Leray-Lions operator of p -Laplacian type. If p < γ < N and the right-hand side is a Radon measure with singularity of order γ at x 0 Ω , then any supersolution in W l o c 1 , p ( Ω ) has singularity of order at least ( γ - p ) ( p - 1 ) at x 0 . In the proof we exploit a pointwise estimate of 𝒜 -superharmonic solutions, due to Kilpeläinen and Malý, which involves Wolff’s potential of Radon’s measure.

Gevrey hypoellipticity for a class of degenerated quasi-elliptic operators

Genadij O. Hakobyan, V. N. Margaryan (2003)

Commentationes Mathematicae Universitatis Carolinae

The problems of Gevrey hypoellipticity for a class of degenerated quasi-elliptic operators are studied by several authors (see [1]–[5]). In this paper we obtain the Gevrey hypoellipticity for a degenerated quasi-elliptic operator in 2 , without any restriction on the characteristic polyhedron.

Global attractivity, oscillation and Hopf bifurcation for a class of diffusive hematopoiesis models

Xiao Wang, Zhixiang Li (2007)

Open Mathematics

In this paper, we discuss the special diffusive hematopoiesis model P ( t , x ) t = Δ P ( t , x ) - γ P ( t , x ) + β P ( t - τ , x ) 1 + P n ( t - τ , x ) with Neumann boundary condition. Sufficient conditions are provided for the global attractivity and oscillation of the equilibrium for Eq. (*), by using a new theorem we stated and proved. When P(t, χ) does not depend on a spatial variable χ ∈ Ω, these results are also true and extend or complement existing results. Finally, existence and stability of the Hopf bifurcation for Eq. (*) are studied.

Global existence and blow up of solutions for a completely coupled Fujita type system of reaction-diffusion equations

Joanna Rencławowicz (1998)

Applicationes Mathematicae

We examine the parabolic system of three equations u t - Δu = v p , v t - Δv = w q , w t - Δw = u r , x ∈ N , t > 0 with p, q, r positive numbers, N ≥ 1, and nonnegative, bounded continuous initial values. We obtain global existence and blow up unconditionally (that is, for any initial data). We prove that if pqr ≤ 1 then any solution is global; when pqr > 1 and max(α,β,γ) ≥ N/2 (α, β, γ are defined in terms of p, q, r) then every nontrivial solution exhibits a finite blow up time.

Currently displaying 1 – 15 of 15

Page 1