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1.
We obtain a local regularity result for solutions to Kψ,θ-obstacle problem of A-harmonic equation divA(x,u(x),▽u(x))=0,where A:Ω× R×Rn → Rn is a Carath'eodory function satisfying some coercivity and growth conditions with the natural exponent 1pn,the obstacle function ψ≥0,and the boundary data θ∈W1,p(?).  相似文献   

2.
In this paper we study the oscillation of the retarded differential equation x′(t)+∫abp(t,ξ)x[g(t,ξ)]dσ(ξ)=0 (b>a) (1)and the advanced differential equation x′(t)-∫abp(t,ξ)x[g(t,ξ)]dσ(ξ)=0 (b>a) (2) We improved the main results of [1-4].  相似文献   

3.
In this note, we establish some estimates of solutions of the scalar Ginzburg-Landau equation and other nonlinear Laplacian equation △u =f(x, u). This will give an estimate of the Hausdorff dimension for the free boundary of the obstacle problem.  相似文献   

4.
杨小京 《数学进展》2001,30(3):283-285
In [1], Lu discussed the existence of positive solution for the BVPwhere f: [0, 1] × [0, ∞) → R is continuous and satisfies the following conditions(H1) There exists an M > 0 such that(H2) limx→∞ f(t, x)/x =∞uniformly for t [α,β] (0, 1) for some α < β and λ > 0 is a parameter.In this paper, the result of [1] is generalized to the following 2n-th-order BVPThe result of this paper isTheorem 1 Assume (H1) and (H2) hold. Then the BVP (3)-(4) has a positive solutionifλ > 0 is sm…  相似文献   

5.
Consider the following Cauchy problem:u_t = div(|▽u ~m |~ p-2▽u~m),(x,t) ∈ST=R~N ×(0,T),u(x,0) = μ,x ∈R~N,where 1相似文献   

6.
Our interest is to determine the critical Fujita exponent concerned withthe following initial-boundary value problem ut= Δum, x ∈RN+, t>0, (1) u(x,0)=u0(x), x∈RN+, (2) -(um)/(x1)=up, x1=0, t>0, (3) where RN+=(x1, x′)| x′∈R{N-1, x1>0,m>1, p>0, and u0(x) is a nonnegative bounded function with compact supportsatisfying thecompatibility condition -(um0(x))/(x1)=up0(x), x1=0. We call p0 the critical global existence exponent if ithas the following property: if p>p0, there always exist nonglobalsolutions of the problem (1)--(3) while if 0pc small data solutionsexist globally in time while large data solutions are nonglobal.  相似文献   

7.
51. IntroductionThe aim of thi8 paPer is to establish the stability criteria for the indnite de1ay differenceequations of the formx(n 1) = F(n,x.) for n E Z, (1'l)where F: Z x CH -- Rk, Z denotes the integer set, Rh is the n-dimensional Euclidean space,CH = {T E C: llWII < H} fOr some constan H > 0, whileC = {yt: {... l --2, --1,0} - Rk l W is bounded}withllytIl = sup IW(8)I for W E C,8<0and x.(8) = x(n 8) for 8 5 0. Here, and in the sequel, l' I is a norm in Rk, and we atwa…  相似文献   

8.
This paper is concerned with the initial-boundary value problem for damped wave equations with a nonlinear convection term in the multi-dimensional half space R n + : u tt u + u t + divf (u) = 0, t > 0, x = (x 1 , x ′ ) ∈ R n + := R + × R n 1 , u(0, x) = u 0 (x) → u + , as x 1 → + ∞ , u t (0, x) = u 1 (x), u(t, 0, x ′ ) = u b , x ′ = (x 2 , x 3 , ··· , x n ) ∈ R n 1 . (I) For the non-degenerate case f ′ 1 (u + ) < 0, it was shown in [10] that the above initialboundary value problem (I) admits a unique global solution u(t, x) which converges to the corresponding planar stationary wave φ(x 1 ) uniformly in x 1 ∈ R + as time tends to infinity provided that the initial perturbation and/or the strength of the stationary wave are sufficiently small. And in [10] Ueda, Nakamura, and Kawashima proved the algebraic decay estimates of the tangential derivatives of the solution u(t, x) for t → + ∞ by using the space-time weighted energy method initiated by Kawashima and Matsumura [5] and improved by Nishihkawa [7]. Moreover, by using the same weighted energy method, an additional algebraic convergence rate in the normal direction was obtained by assuming that the initial perturbation decays algebraically. We note, however, that the analysis in [10] relies heavily on the assumption that f ′ (u) < 0. The main purpose of this paper isdevoted to discussing the case of f ′ 1 (u b ) ≥ 0 and we show that similar results still hold for such a case. Our analysis is based on some delicate energy estimates.  相似文献   

9.
61. IntroductionAs well knoWn, the solutionS of semilinear Parabolic equations at = An -- ac, 0 < q < 1have the ISS (the thetantaneous shrinking of the support) ~erty (see 11--5]).Such PrOPerty is d~d as follows.Defiallion 1.1. A hoction u E La(Q) is sold to haw the ISS p~rty, ijjor augr > 0, there hots a POsiboe n~ber R = R(T) such thatu(z, t) = 0for a. e. (z,t) e (R" \ Ba) x (T, co), tDhere AN is the N-dimensional Euclidean space,and Q = AN X (0, co).UP to the preseDt, there…  相似文献   

10.
The aim of this paper is to discuss the existence and uniqueness ofsolutions for the porous medium equation ut-(u^m)xx=μ(x) in (x,t)∈R&#215;(0,+∞) with initial condition u(x,0)=u0(x) x∈(-∞,+∞),where μ(x) is a nonnegative finite Radon measure, u0∈L^1 (R)∩L^∞ (R) is a nonnegative function, and m&gt;1, and R≡(-∞, +∞).  相似文献   

11.
<正>Submission Authors must use LaTeX for typewriting,and visit our website www.actamath.com to submit your paper.Our address is Editorial Office of Acta Mathematica Sinica,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,P.R.China.  相似文献   

12.
正August 10-14,2015Beijin,China The International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists  相似文献   

13.
14.
The present paper investigates the fractal structure of fractional integrals of Weierstrass functions. The ezact box dimension for such functions many important cases is established. We need to point out that, although the result itself achieved in the present paper is interesting, the new technique and method should be emphasized. These novel ideas might be useful to establish the box dimension or Hausdorff dimension (especially for the lower bounds) for more general groups of functions.  相似文献   

15.
English Series     
正1 Aims and Scope Acta Mathematicae Applicatae Sinica(English Series)is a quarterly journal established by the Chinese Mathematical Society.The journal publishes high quality research papers from all branches of applied mathematics,particularly welcomes those from partial differential equations,computational mathematics,applied probability,mathematical finance,statistics,dynamical systems,optimization and management science.  相似文献   

16.
17.
We characterize congruence lattices of standard QBCC-algebras and their connection with the congruence lattices of congruence kernels. Work on the paper was supported by Council of Czech Government No J14/98:153100011.  相似文献   

18.
A new class of sets in ideal topological spaces is introduced and using these sets, a decomposition of continuity is given.   相似文献   

19.
We obtain (a) necessary and sufficient conditions and (b) sufficient conditions for a compact (countably compact) set to be closed in products (sequential products) and subspaces (sequential subspaces) of normal spaces. As a consequence of these, sufficient conditions are obtained for (i) the closedness of arbitrary (countable) union of closed sets and (ii) the equality of the union of the closures and the closure of the union of arbitrary (countable) families of sets in these spaces. It is also shown that these results do not hold for quotients of even T 4,-spaces.  相似文献   

20.
The current paper considers the problem of recovering a function using a limited number of its Fourier coefficients. Specifically, a method based on Bernoulli-like polynomials suggested and developed by Krylov, Lanczos, Gottlieb and Eckhoff is examined. Asymptotic behavior of approximate calculation of the so-called "jumps" is studied and asymptotic L2 constants of the rate of convergence of the method are computed.  相似文献   

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