共查询到20条相似文献,搜索用时 843 毫秒
1.
王阳 《数学物理学报(B辑英文版)》2007,27(2):274-282
This article consider, for the following heat equation ut/|x|s-△pu=uq,(x,t)∈Ω×(0,T), u(x,t)=0,(x,t)∈(?)Ω×(0,T), u(x,0)=u0(x),u0(x)≥0,u0(x)(?)0 the existence of global solution under some conditions and give two sufficient conditions for the blow up of local solution in finite time, whereΩis a smooth bounded domain in RN(N>p),0∈Ω,△pu=div(|▽u|p-2▽u),0≤s≤2,p≥2,p-1
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2.
Let X be a metric space andμa finite Borel measure on X. Let pμq,t and pμq,t be the packing premeasure and the packing measure on X, respectively, defined by the gauge (μB(x,r))q(2r)t, where q, t∈R. For any compact set E of finite packing premeasure the authors prove: (1) if q≤0 then pμq,t(E)=pμq,t(E);(2)if q>0 andμis doubling on E then pμq,t(E) and pμq,t(E) are both zero or neither. 相似文献
3.
This note shows that every positive solution to the following third order non–autonomous max-type difference equationwhen is a three-periodic sequence of positive numbers, is periodic with period three. The same result was proved for the following min-type difference equation 相似文献
4.
We consider the eigenvalue problems for boundary value problems of second order difference equations(1) and(2) Comparison results for the eigenvalues of the problem (1) and the problem (2) are established. 相似文献
5.
Positive solutions of three-point boundary value problems for systems of nonlinear second order ordinary differential equations 总被引:1,自引:0,他引:1
In this paper, we study the three-point boundary value problems for systems of nonlinear second order ordinary differential equations of the form Under some conditions, we show the existence and multiplicity of positive solutions of the above problem by applying the fixed point index theory in cones. 相似文献
6.
We consider the problem of deciding whether a given rational function has a power series expansion with all its coefficients positive. Introducing an elementary transformation that preserves such positivity we are able to provide an elementary proof for the positivity of Szegö's function which has been at the historical root of this subject starting with Szegö. We then demonstrate how to apply the transformation to prove a 4-dimensional generalization of the above function, and close with discussing the set of parameters (a,b) such that has positive coefficients. 相似文献
7.
Blow-up analysis for a system of heat equations with nonlinear flux which obey different laws 总被引:1,自引:0,他引:1
We consider a system of heat equations ut=Δu and vt=Δv in Ω×(0,T) completely coupled by nonlinear boundary conditions We prove that the solutions always blow up in finite time for non-zero and non-negative initial values. Also, the blow-up only occurs on ∂Ω with for p,q>0, 0≤α<1 and 0≤β<p. 相似文献
8.
In this paper, the existence of a positive solution of the boundary value problem of the following fourth-order nonlinear differential equation: is discussed. 相似文献
9.
In this work the existence of a global solution for the mixed problem associated to the nonlinear equationis proved in a Hilbert space framework by using Galerkin method. 相似文献
10.
Ivan Kiguradze Tariel Kiguradze 《Nonlinear Analysis: Theory, Methods & Applications》2008,69(7):1914-1933
In the rectangle Ω=[0,a]×[0,b] for the nonlinear hyperbolic equation the boundary value problems of the type are considered, where and are linear bounded functionals.Sufficient conditions of solvability and unique solvability of the general problem and its particular cases (Nicoletti type, Dirichlet, Lidstone and Periodic problems) are established. 相似文献
11.
We consider in this paper the problem(0.1) where Ω is the unit ball in centered at the origin, 0α<pN, β>0, N8, p>1, qε>1. Suppose qε→q>1 as ε→0+ and qε,q satisfy respectively we investigate the asymptotic behavior of the ground state solutions (uε,vε) of (0.1) as ε→0+. We show that the ground state solutions concentrate at a point, which is located at the boundary. In addition, the ground state solution is non-radial provided that ε>0 is small. 相似文献
12.
We prove the Marcinkiewicz–Zygmund Strong Law of Large Numbers for U-statistics of strictly stationary, absolutely regular observations (ξi)i≥1. Under suitable moment conditions and conditions on the mixing rate, we show that for some γ≥0, in the non-degenerate case, and in the degenerate case. 相似文献
13.
In this paper the homogenization of degenerate nonlinear parabolic equations where a(t,y,λ) is periodic in (t,y), is studied via a weighted compensated compactness result. 相似文献
14.
Blow-up of positive-initial-energy solutions of a nonlinear viscoelastic hyperbolic equation 总被引:2,自引:0,他引:2
Salim A. Messaoudi 《Journal of Mathematical Analysis and Applications》2006,320(2):902-915
In this paper, we consider the nonlinear viscoelastic equation with initial conditions and Dirichlet boundary conditions. For nonincreasing positive functions g and for p>m, we prove that there are solutions with positive initial energy that blow up in finite time. 相似文献
15.
Global existence and blow-up of solutions for a system of nonlinear viscoelastic wave equations with damping and source 总被引:1,自引:0,他引:1
In this paper we investigate the global existence and finite time blow-up of solutions to the system of nonlinear viscoelastic wave equations in Ω×(0,T) with initial and Dirichlet boundary conditions, where Ω is a bounded domain in . Under suitable assumptions on the functions gi(), , the initial data and the parameters in the equations, we establish several results concerning local existence, global existence, uniqueness and finite time blow-up property. 相似文献
16.
By using the integral operator, we establish some oscillation criteria for the damped half-linear PDE The results are extensions of integral averaging technique of Kamenev and include earlier results of Usami, Xu and Xing. 相似文献
17.
We consider the following nonlinear elliptic equation with singular nonlinearity: where α>β>1, a>0, and Ω is an open subset of , n2. Let uH1(Ω) with and be a nonnegative stationary solution. If we denote the zero set of u by we shall prove that the Hausdorff dimension of Σ is less than or equal to . 相似文献
18.
Let be a bounded domain such that 0Ω. Denote by , the set of all complex polynomials of degree at most n. Let where . We relate the maximal polynomial range to the geometry of Ω. 相似文献
19.
By using a fixed point theorem of strict-set-contraction, some new criteria are established for the existence of positive periodic solutions of the following periodic neutral Lotka–Volterra system with state dependent delays where (i,j=1,2,…,n) are ω-periodic functions and (i=1,2,…,n) are ω-periodic functions with respect to their first arguments, respectively. 相似文献
20.
Let H,V and K be separable Hilbert spaces. In this paper we consider the existence and uniqueness of energy solutions to the following stochastic evolution equation: where is a linear bounded operator with coercivity, monotone condition and hemicontinuity, and are measurable functions and satisfy the local non-Lipschitz condition proposed by the author [T. Taniguchi, Successive approximations to solutions of stochastic differential equations, J. Differential Equations 96 (1992) 152–169]. 相似文献