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1.
In this article,we prove that viscosity solutions of the parabolic inhomogeneous equations can be characterized using asymptotic mean value properties for all p ≥ 1,including p = 1and p = ∞.We also obtain a comparison principle for the non-negative or non-positive inhomogeneous term / for the corresponding initial-boundary value problem and this in turn implies the uniqueness of solutions to such a problem.  相似文献   

2.
The aim of this work is to investigate the integrability properties of the maximal operator Mu,associated with a non-doubling measure μ defined on Rn. We start by establishing for a wide class of radial and increasing measures μ that Mu is bounded on all the spaces Lu^p(R^n),P〉1.Also,we show that there is a radial and increasing measure p for which Mμ does not map Lμ^p(R^n) into weak Lμ^p(R^n),1≤p〈∞.  相似文献   

3.
Let E be a cookie-cutter set with dimH E =s. It is known that the Hausdorff s-measure and the packing s-measure of the set E are positive and finite. In this paper, we prove that for a gauge function g the set E has positive and finite Hausdorff g-measure if and only if 0 〈 liminft→0 g(t)/ts 〈 ∞. Also, we prove that for a doubling gauge function g the set E has positive and finite packing g-measure if and only if 0 〈 lim supt→0 g(t)/ts 〈 ∞.  相似文献   

4.
In this paper, we consider some classes of 2π-periodic convolution functions Bp, and Kp with kernels having certain oscillation properties, which include the classical Sobolev class as special case. With the help of the spectral of nonlinear integral equations, we determine the exact values of Bernstein n-width of the classes Bp, Kp in the space Lp for 1 〈 p 〈 ∞.  相似文献   

5.
Let n≥ 2 and let L be a second-order elliptic operator of divergence form with coefficients consisting of both an elliptic symmetric part and a BMO anti-symmetric part in Rn.In this article,we consider the weighted Kato square root problem for L.More precisely,we prove that the square root L1/2 satisfies the weighted Lp estimates ■ for any p∈(1,∞) and ω∈ Ap(Rn)(the class of Muckenhoupt weights),and that ■ for any p ∈(1,2+ε) and ■(the class o...  相似文献   

6.
Using the technique of block-operators, in this note, we prove that if P and Q are idempotents and (P - Q)^2n+1 is in the trace class, then (P - Q)^2m+1 is also in the trace class and tr(P - Q)^2m+1 = dim(k(P) ∩ k(Q)^⊥) -dim(k(P)^⊥ N k(Q)), for all m ≥ n. Moreover, we prove that dim(k(P)∩ k(Q)^⊥) = dim(k(P)^⊥ ∩k(Q)) if and only if there exists a unitary U such that UP = QU and PU = UQ, where k(T) denotes the range of T. Keywords Fredholm, orthogonal projection, positive operator  相似文献   

7.
Parametrized Area Integrals on Hardy Spaces and Weak Hardy Spaces   总被引:3,自引:1,他引:2  
In this paper, the authors prove that if Ω satisfies a class of the integral Dini condition, then the parametrized area integral μΩ,S^ρ is a bounded operator from the Hardy space H1 (R^n) to L1 (R^n) and from the weak Hardy space H^1,∞ (R^n) to L^1,∞ (R^n), respectively. As corollaries of the above results, it is shown that μΩ,S^ρ is also an operator of weak type These conclusions are substantial improvement and (1, 1) and of type (p,p) for 1 〈 p 〈 2, respectively extension of some known results.  相似文献   

8.
In this paper, we prove that under some restricted conditions, the non-bandiimited functions can be reconstructed by the multidimensional sampling theorem of Hermite type in the space of Lp(R^n), 1 〈 p 〈 ∞.  相似文献   

9.
In this article, we give an operator transform T (*) from class A operator to the class of hyponormal operators. It is different from the operator transform T defined by M. Ch and T. Yamazaki. Then, we show that σ(T ) = σ( T (*)) and σa(T )\{0} = σa( T (*))\{0}, in case T belongs to class A. Next, we obtain some relations between T and T (9).  相似文献   

10.
In this paper we consider a proper subclass nA of the full class of spirallike mappings on the Euclidean unit ball Bn in Cn with respect to a given linear operator A. We use the method of subordination chains to obtain an upper growth result for nA , and we obtain various examples of mappings in the same class of normalized biholomorphic mappings on the unit ball Bn in Cn . We also prove that the class nA is compact, while the full class of spirallike mappings with respect to a linear operator need not be compact in dimension n≥2, even when the operator is diagonal. This is one of the motivations for considering the class nA . Finally we prove that if f is a quasiregular strongly spirallike mapping on Bn such that ||[Df(z)]-1 Af(z)|| is uniformly bounded on Bn , then f extends to a homeomorphism of R2n onto itself. In addition, if A + A* = 2aI n for some a 0, this extension is also quasiconformal on R2n .  相似文献   

11.
The goal of this paper is to study the multiplicity result of positive solutions of a class of degenerate elliptic equations. On the basis of the mountain pass theorems and the sub- and supersolutions argument for p-Laplacian operators, under suitable conditions on the nonlinearity f(x, s), we show the following problem:-△pu=λu^α-a(x)u^q in Ω,u│δΩ=0 possesses at least two positive solutions for large λ, where Ω is a bounded open subset of R^N, N ≥ 2, with C^2 boundary, λ is a positive parameter, Ap is the p-Laplacian operator with p 〉 1, α, q are given constants such that p - 1 〈α 〈 q, and a(x) is a continuous positive function in Ω^-.  相似文献   

12.
Making use of the fractional differential operator, we impose and study a new class of analytic functions in the unit disk (type fractional differential equation). The main object of this paper is to investigate inclusion relations, coefficient bound for this class. Moreover, we discuss some geometric properties of the fractional differential operator.  相似文献   

13.
王莉雅  汪文珑 《东北数学》2008,24(2):95-100
In this paper we investigate the asymptotic spectrum and accumulation of a transport operator A in slab geometry with continuous energy, anisotropic scattering and inhomogeneous medium. In L^p (1 ≤ p 〈 +∞) space we show a series of new results for the asymptotic point spectrum and accumulation of A.  相似文献   

14.
It is well known that the commutator Tb of the singular integral operator T with a BMO function b is bounded on L^P(R^n), 1 〈 p 〈 ∞. In this paper, we consider the endpoint estimates for a kind of commutator of singular integrals. A BMO-type estimate for Tb is obtained under the assumption b ∈ LMO.  相似文献   

15.
Let {X(t), t ≥ 0} be a Lévy process with EX(1) = 0 and EX^2(1) 〈 ∞. In this paper, we shall give two precise asymptotic theorems for {X(t), t 〉 0}. By the way, we prove the corresponding conclusions for strictly stable processes and a general precise asymptotic proposition for sums of i.i.d. random variables.  相似文献   

16.
Let T be a bounded linear operator on a complex Hilbert space H. In this paper we introduce a new class denoted by l-*-A, of operators satisfying T*|T2|T≥ T*|T*|2T, and we prove the basic properties of these operators. Using these results, we also prove that if T or T* ∈l-*-A, then w(f(T)) = f(w(T)), σea(f(T)) = f(σea(T)) for every f C H(σ(T)), where g(σ(T)) denotes the set of all analytic functions on an open neighborhood of σ(T).  相似文献   

17.
The Picard dimension dimμ of a signed local Kato measure μ on the punctured unit ball in R^d, d ≥ 2, is the cardinal number of the set of extremal rays of the convex cone of all continuous solutions u ≥ 0 of the time-independent SchrSdinger equation Δu -- uμ = 0 on the punctured ball 0 〈 ||x|| 〈 1, with vanishing boundary values on the sphere ||x|| = 1. Using potential theory associated with the Schrodinger operator we prove, in this paper, that the dimμ for a signed radial Kato measure is 0, 1 or +∞. In particular, we obtain the Picard dimension of locally Holder continuous functions P proved by Nakai and Tada by other methods.  相似文献   

18.
Abstract The main purpose of this article is to prove a collection of new nxea point theorems for (ws)-compact and so-called 1-set weakly contractive operators under Leray- Schauder boundary condition. We also introduce the concept of semi-closed operator at the origin and obtain a series of new fixed point theorems for such class of operators. As consequences, we get new fixed point existence for (ws)-compact (in particular nonexpansive) self mappings unbounded closed convex subset of Banach spaces. The main condition in our results is formulated in terms of axiomatic measures of weak noncompactness. Later on, we give an application to generalized Hammerstein type integral equations.  相似文献   

19.
The adaptive regularization method is first proposed by Ryzhikov et al. in [6] for the deconvolution in elimination of multiples which appear frequently in geoscience and remote sensing. They have done experiments to show that this method is very effective. This method is better than the Tikhonov regularization in the sense that it is adaptive, i.e., it automatically eliminates the small eigenvalues of the operator when the operator is near singular. In this paper, we give theoretical analysis about the adaptive regularization. We introduce an a priori strategy and an a posteriori strategy for choosing the regularization parameter, and prove regularities of the adaptive regularization for both strategies. For the former, we show that the order of the convergence rate can approach O(||n||^4v/4v+1) for some 0 〈 v 〈 1, while for the latter, the order of the convergence rate can be at most O(||n||^2v/2v+1) for some 0 〈 v 〈 1.  相似文献   

20.
In this paper,we prove that the necessary and sufficient condition for a Toeplitz operator Tu on the Dirichlet space to be hyponormal is that the symbol u is constant for the case that the projection of u in the Dirichlet space is a polynomial and for the case that u is a class of special symbols,respectively.We also prove that a Toeplitz operator with harmonic polynomial symbol on the harmonic Dirichlet space is hyponormal if and only if its symbol is constant.  相似文献   

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