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1.
Let Ω be a bounded open subset of ℝ n , n > 2. In Ω we deduce the global differentiability result
for the solutions uH 1 (Ω, ℝ n ) of the Dirichlet problem
with controlled growth and nonlinearity q = 2. The result was obtained by first extending the interior differentiability result near the boundary and then proving the global differentiability result making use of a covering procedure.  相似文献   

2.
We study the limit as n goes to +∞ of the renormalized solutions u n to the nonlinear elliptic problems
where Ω is a bounded open set of ℝ N , N≥ 2, and μ is a Radon measure with bounded variation in Ω. Under the assumption of G-convergence of the operators , defined for , to the operator , we shall prove that the sequence (u n ) admits a subsequence converging almost everywhere in Ω to a function u which is a renormalized solution to the problem
  相似文献   

3.
The problem of establishing necessary and sufficient conditions for l.s.c. under PDE constraints is studied for a special class of functionals:
with respect to the convergence un → u in measure, vn ⇀ v in Lp(Ω;ℝd) in W−1,p(Ω), and χn ⇀ χ in Lp(Ω), where χn ∈ Z:= {χ ∈ L(Ω): 0 ≤ χ(x) ≤ 1 for a.e. x}. Here is a constant-rank partial differential operator. The main result is that if the characteristic cone of has the full dimension, then the l.s.c. is equivalent to the fact that the F± are both -quasiconvex and
for a.e. x ∈ Ω and for all u ∈ ℝd. As a corollary, we obtain several results for the functional
with respect to the same convergence. We show that this functional is l.s.c. iff
Bibliography: 14 titles. Published in Zapiski Nauchnykh Seminarov POMI, Vol. 318, 2004, pp. 100–119.  相似文献   

4.
We investigate the boundary growth of positive superharmonic functions u on a bounded domain Ω in , n ≥ 3, satisfying the nonlinear elliptic inequality
where c >  0, α ≥ 0 and p >  0 are constants, and is the distance from x to the boundary of Ω. The result is applied to show a Harnack inequality for such superharmonic functions. Also, we study the existence of positive solutions, with singularity on the boundary, of the nonlinear elliptic equation
where V and f are Borel measurable functions conditioned by the generalized Kato class.  相似文献   

5.
We study the existence of an integral representation for the functional
when μ is a positive Radon measure on ℝN, Ω⊂ℝN is a bounded open set, and is a continuous function not necessarily convex with growth conditions of order p>1. Mathematics Subject Classification (2000)  49J45, 49Q20  相似文献   

6.
Consider a plate occupying in a reference configuration a bounded open set Ω ⊂ ℝ 2 , and let be its stored-energy function. In this paper we are concerned with relaxation of variational problems of type:
, where with is the scalar product in ℝ 3 and is the external loading per unit surface. We take into account the fact that an infinite amount of energy is required to compress a finite surface of the plate into zero surface, i.e.,
Mathematics Subject Classification (2000) 49J45  相似文献   

7.
The paper is devoted to the study of the behavior of the following mixed problem for large values of time:
where Ω is an unbounded region of ℝ n with, generally speaking, noncompact boundary ; the surface Γ is star-shaped (relative to the origin), ν is the unit outer normal to ∂Ω; and the initial functionsf andg are assumed to be sufficiently smooth and finite. Under certain restrictions on the part of the boundary Γ2 constrained by the impedance condition, we establish that one can match the impedanceg≥0 (characterizing the absorption of energy by the surface Γ2) to the geometric properties of this surface so that the energy on an arbitrary compact set will decay at a rate characteristic for the first mixed problem. Translated fromMatematicheskie Zametki, Vol. 66, No. 3, pp. 393–400, September, 1999.  相似文献   

8.
Let u=u(x,t,uo)represent the global solution of the initial value problem for the one-dimensional fluid dynamics equation ut-εuxxt+δux+γHuxx+βuxxx+f(u)x=αuxx,u(x,0)=uo(x), whereα〉0,β〉0,γ〉0,δ〉0 andε〉0 are constants.This equation may be viewed as a one-dimensional reduction of n-dimensional incompressible Navier-Stokes equations. The nonlinear function satisfies the conditions f(0)=0,|f(u)|→∞as |u|→∞,and f∈C^1(R),and there exist the following limits Lo=lim sup/u→o f(u)/u^3 and L∞=lim sup/u→∞ f(u)/u^5 Suppose that the initial function u0∈L^I(R)∩H^2(R).By using energy estimates,Fourier transform,Plancherel's identity,upper limit estimate,lower limit estimate and the results of the linear problem vt-εv(xxt)+δvx+γHv(xx)+βv(xxx)=αv(xx),v(x,0)=vo(x), the author justifies the following limits(with sharp rates of decay) lim t→∞[(1+t)^(m+1/2)∫|uxm(x,t)|^2dx]=1/2π(π/2α)^(1/2)m!!/(4α)^m[∫R uo(x)dx]^2, if∫R uo(x)dx≠0, where 0!!=1,1!!=1 and m!!=1·3…(2m-3)…(2m-1).Moreover lim t→∞[(1+t)^(m+3/2)∫R|uxm(x,t)|^2dx]=1/2π(x/2α)^(1/2)(m+1)!!/(4α)^(m+1)[∫Rρo(x)dx]^2, if the initial function uo(x)=ρo′(x),for some functionρo∈C^1(R)∩L^1(R)and∫Rρo(x)dx≠0.  相似文献   

9.
We consider the following semilinear elliptic equation with singular nonlinearity:
where and Ω is an open subset in . Let u be a non-negative finite energy stationary solution and be the rupture set of u. We show that the Hausdorff dimension of Σ is less than or equal to [(n−2) α+(n+2)]/(α +1).  相似文献   

10.
Let Ω be an open bounded set in ℝN, N≥3, with connected Lipschitz boundary ∂Ω and let a(x,ξ) be an operator of Leray–Lions type (a(⋅,∇u) is of the same type as the operator |∇u|p−2u, 1<p<N). If τ is the trace operator on ∂Ω, [φ] the jump across ∂Ω of a function φ defined on both sides of ∂Ω, the normal derivative ∂/∂νa related to the operator a is defined in some sense as 〈a(⋅,∇u),ν〉, the inner product in ℝN, of the trace of a(⋅,∇u) on ∂Ω with the outward normal vector field ν on ∂Ω. If β and γ are two nondecreasing continuous real functions everywhere defined in ℝ, with β(0)=γ(0)=0, fL1(ℝN), gL1(∂Ω), we prove the existence and the uniqueness of an entropy solution u for the following problem,
in the sense that, if Tk(r)=max {−k,min (r,k)}, k>0, r∈ℝ, ∇u is the gradient by means of truncation (∇u=DTku on the set {|u|<k}) and , u measurable; DTk(u)∈Lp(ℝN), k>0}, then and u satisfies,
for every k>0 and every . Mathematics Subject Classifications (2000)  35J65, 35J70, 47J05.  相似文献   

11.
Solutions of elliptic problems with nonlinearities of linear growth   总被引:1,自引:0,他引:1  
In this paper, we study existence of nontrivial solutions to the elliptic equation
and to the elliptic system
where Ω is a bounded domain in with smooth boundary ∂Ω, , f (x, 0) = 0, with m ≥ 2 and . Nontrivial solutions are obtained in the case in which the nonlinearities have linear growth. That is, for some c > 0, for and , and for and , where I m is the m × m identity matrix. In sharp contrast to the existing results in the literature, we do not make any assumptions at infinity on the asymptotic behaviors of the nonlinearity f and . Z. Liu was supported by NSFC(10825106, 10831005). J. Su was supported by NSFC(10831005), NSFB(1082004), BJJW-Project(KZ200810028013) and the Doctoral Programme Foundation of NEM of China (20070028004).  相似文献   

12.
Let Ω be a bounded convex domain in . We consider constrained minimization problems related to the Euler-Lagrange equation
over classes of functions (Ω) with convex super level sets. We then search for sufficient conditions ensuring that the minimizer obtained is a classical solution to the above equation. Supported by ESF activity “Global and geometrical aspects of nonlinear P.D.E.’s.” Received: 4 April 2006  相似文献   

13.
Let Ω be an open bounded domain in ℝN(N ≥ 3) and . We are concerned with two kinds of critical elliptic problems. The first one is
(*)
where 0 ∈ Ω, , 2 < m < 2* and λ > 0. By using the fountain theorem and concentration estimates, if N ≥ 7 and θ > 0, we establish the existence of infinitely many solutions for the following regularization of (*) with small number ϵ > 0
Then if θ > 0 is suitably small, we obtain many solutions for problem (*) by taking the process of approximation. The second problem is
where q ∈ (0, 1), t > 0. By using similar methods as in (*), we prove that if N ≥ 7, and t > 0, there exist infinitely many solutions with positive energy. In particular, we give a positive answer to one open problem proposed by Ambrosetti, Brezis and Cerami [1].  相似文献   

14.
This paper deals with the existence of weak solutions in W 01(Ω) to a class of elliptic problems of the form
in a bounded domain Ω of ℝ N . Here a satisfies
for all ξ∈ℝ N , a.e. x∈Ω, , h 1L loc 1(Ω), h 1(x)1 for a.e. x in Ω; λ 1 is the first eigenvalue for −Δ p on Ω with zero Dirichlet boundary condition and g, h satisfy some suitable conditions.   相似文献   

15.
A Robin boundary problem with Hardy potential and critical nonlinearities   总被引:1,自引:0,他引:1  
Let Ω be a bounded domain with a smooth C 2 boundary in ℝn (n ≥ 3), 0 ∈ , and υ denote the unit outward normal to ∂Ω. In this paper, we are concerned with the following class of boundary value problems:
(*)
where 2* = 2n/(n − 2) is the limiting exponent for the embedding of H 1(Ω) into L p (Ω), 2 < p < 2*, , η ≥ 0 and λ ∈ ℝ1 are parameters, and α(x) ∈ C(∂Ω), α(x) ≥ 0. Through a compactness analysis of the functional corresponding to the problem (*), we obtain the existence of positive solutions for this problem under various assumptions on the parameters μ, λ and the fact that 0 ∈ Ω or 0 ∈ ∂Ω. The research was supported by NSFC(10471052, 10571069, 10631030) and the Key Project of Chinese Ministry of Education(107081) and NCET-07-0350.  相似文献   

16.
Let H be an infinite-dimensional real Hilbert space equipped with the scalar product (⋅,⋅) H . Let us consider three linear bounded operators,
We define the functions
where a i H and α i ∈ℝ. In this paper, we discuss the closure and the convexity of the sets Φ H ⊂ℝ2 and F H ⊂ℝ3 defined by
Our work can be considered as an extension of Polyak’s results concerning the finite-dimensional case.  相似文献   

17.
We establish the optimal regularity (of class W 2 ) of a solution to the two-phase obstacle problem
with a nonhomogeneous Dirichlet condition in a bounded domain Ω ⊂ ℝn with smooth boundary ∂Ω. Bibliography: 10 titles. __________ Translated from Problemy Matematicheskogo Analiza, No. 34, 2006, pp. 3–11.  相似文献   

18.
Let Ω be a smooth bounded domain of with N ≥ 5. In this paper we prove, for ɛ > 0 small, the nondegeneracy of the solution of the problem
under a nondegeneracy condition on the critical points of the Robin function. Our proof uses different techniques with respect to other known papers on this topic.  相似文献   

19.
We consider the following Liouville equation in
For each fixed and a j  > 0 for 1 ≤ jk, we construct a solution to the above equation with the following asymptotic behavior:
  相似文献   

20.
In this paper, we study the asymptotic behaviour of the scattering phases(λ) of the Dirichlet Laplacian associated with obstacle , where Ω is a bounded open subset of ℝ n (n≥2) with non-smooth boundary ∂Ω and connected complement Ω e =ℝ n . We can prove that if Ω satisfies a certain geometrical condition, then
where ,d n>0 depending only onn, and |·| j (j = n - l, n) is aj- dimensional Lebesgue measure. Research partially supported by the Natural Science Foundation of China and the Grant of Chinese State Education Committee  相似文献   

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