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1.
Abstract   Let ξ i ∈ (0, 1) with 0 < ξ1 < ξ2 < ··· < ξ m−2 < 1, a i , b i ∈ [0,∞) with and . We consider the m-point boundary-value problem
where f(x, y) ≥ −M, and M is a positive constant. We show the existence and multiplicity of positive solutions by applying the fixed point theorem in cones. *Supported by the NSFC (10271095). GG-110-10736-1003, NWNU-KJCXGC-212 and the Foundation of Major Project of Science and Technology of Chinese Education Ministry  相似文献   

2.
We consider the solutions of refinement equations written in the form
where the vector of functions ϕ = (ϕ 1, ..., ϕ r ) T is unknown, g is a given vector of compactly supported functions on ℝ s , a is a finitely supported sequence of r × r matrices called the refinement mask, and M is an s × s dilation matrix with m = |detM|. Inhomogeneous refinement equations appear in the construction of multiwavelets and the constructions of wavelets on a finite interval. The cascade algorithm with mask a, g, and dilation M generates a sequence ϕ n , n = 1, 2, ..., by the iterative process
from a starting vector of function ϕ 0. We characterize the L p -convergence (0 < p < 1) of the cascade algorithm in terms of the p-norm joint spectral radius of a collection of linear operators associated with the refinement mask. We also obtain a smoothness property of the solutions of the refinement equations associated with the homogeneous refinement equation. This project is supported by the NSF of China under Grant No. 10071071  相似文献   

3.
Some results concerning existence of positive solutions for the singular boundary value problems u^(4)(t)=f(t,u(t)) t∈(0,1) u(0)=u(1)=0 u‘(0)=u‘(1)=0 have been given, where f(t, x) may be singular at t = 0, 1.  相似文献   

4.
Abstract   Let Λ = {λ k } be an infinite increasing sequence of positive integers with λ k →∞. Let X = {X(t), t ∈? R N } be a multi-parameter fractional Brownian motion of index α(0 < α < 1) in R d . Subject to certain hypotheses, we prove that if N < αd, then there exist positive finite constants K 1 and K 2 such that, with unit probability,
if and only if there exists γ > 0 such that
where ϕ(s) = s N/α (log log 1/s) N/(2α), ϕ-p Λ(E) is the Packing-type measure of E,X([0, 1]) N is the image and GrX([0, 1] N ) = {(t,X(t)); ? [0, 1] N } is the graph of X, respectively. We also establish liminf type laws of the iterated logarithm for the sojourn measure of X. Supported by the National Natural Science Foundation of China (No.10471148), Sci-tech Innovation Item for Excellent Young and Middle-Aged University Teachers and Major Item of Educational Department of Hubei (No.2003A005)  相似文献   

5.
Let be a nondecreasing sequence of positive numbers and let l 1,α be the space of real sequences for which . We associate every sequence ξ from l 1,α with a sequence , where ϕ(·) is a permutation of the natural series such that , j ∈ ℕ. If p is a bounded seminorm on l 1,α and , then
Using this equality, we obtain several known statements. __________ Translated from Ukrains'kyi Matematychnyi Zhurnal, Vol. 57, No. 7, pp. 1002–1006, July, 2005.  相似文献   

6.
Summary In the paper we estimate a regressionm(x)=E {Y|X=x} from a sequence of independent observations (X 1,Y 1),…, (X n, Yn) of a pair (X, Y) of random variables. We examine an estimate of a type , whereN depends onn andϕ N is Dirichlet kernel and the kernel associated with the hermite series. Assuming, that E|Y|<∞ and |Y|≦γ≦∞, we give condition for to converge tom(x) at almost allx, provided thatX has a density. if the regression hass derivatives, then converges tom(x) as rapidly asO(nC−(2s−1)/4s) in probability andO(n −(2s−1)/4s logn) almost completely.  相似文献   

7.
The following regularity of weak solutions of a class of elliptic equations of the form are investigated.  相似文献   

8.
In this paper, we obtain positive solution to the following multi-point singular boundary value problem with p-Laplacian operator,{( φp(u'))'+q(t)f(t,u,u')=0,0〈t〈1,u(0)=∑i=1^nαiu(ξi),u'(1)=∑i=1^nβiu'(ξi),whereφp(s)=|s|^p-2s,p≥2;ξi∈(0,1)(i=1,2,…,n),0≤αi,βi〈1(i=1,2,…n),0≤∑i=1^nαi,∑i=1^nβi〈1,and q(t) may be singular at t=0,1,f(t,u,u')may be singular at u'=0  相似文献   

9.
In studying local harmonic analysis on the sphere Sn, R.S. Strichartz introduced certain zonal functions ϕ2(d(x, y)) which satisfy the equation , where Δz is the Laplace operator and δ−y the Dirac measure. The explicit expression of the constant a (λ) is given by R.S. Strichartz in the case that n is odd. Appyling the Apéry identity, we show in this paper that for n even, where wn-1 is the surface area of Sn-1, . The author's research was supported by a grant from NSFC.  相似文献   

10.
In this paper, we discuss the moving-average process Xk = ∑i=-∞ ^∞ ai+kεi, where {εi;-∞ 〈 i 〈 ∞} is a doubly infinite sequence of identically distributed ψ-mixing or negatively associated random variables with mean zeros and finite variances, {ai;-∞ 〈 i 〈 -∞) is an absolutely solutely summable sequence of real numbers.  相似文献   

11.
In this paper, we prove that the weak solutions u∈Wloc^1, p (Ω) (1 〈p〈∞) of the following equation with vanishing mean oscillation coefficients A(x): -div[(A(x)△↓u·△↓u)p-2/2 A(x)△↓u+│F(x)│^p-2 F(x)]=B(x, u, △↓u), belong to Wloc^1, q (Ω)(A↓q∈(p, ∞), provided F ∈ Lloc^q(Ω) and B(x, u, h) satisfies proper growth conditions where Ω ∪→R^N(N≥2) is a bounded open set, A(x)=(A^ij(x)) N×N is a symmetric matrix function.  相似文献   

12.
We consider the multidimensional abstract linear integral equation of Volterra type x(t) (*)∫Rtα(s)x(s)ds=f(t),t∈R,(1)as the limit of discrete Stieltjes-type systems and we prove results on the existence of continuous solutions. The functions x, α and f are Bauach space-valued defined on a compact interval R of R^n Rt is a subinterval of R depending on t ∈ R and (*) f denotes either the Bochner-Lebesgue integral or the Henstock integral. The results presented here generalize those in [1] and are in the spirit of [3]. As a consequence of our approach, it is possible to study the properties of (1) by transferring the properties of the discrete systems, The Henstock integral setting enables us to consider highly oscillating functions.  相似文献   

13.
Let X1, X2, ... be i.i.d. random variables with EX1 = 0 and positive, finite variance σ2, and set Sn = X1 + ... + Xn. For any α > −1, β > −1/2 and for κn(ε) a function of ε and n such that κn(ε) log log n → λ as n ↑ ∞ and , we prove that
*Supported by the Natural Science Foundation of Department of Education of Zhejiang Province (Grant No. 20060237 and 20050494).  相似文献   

14.
Let {xn}n∈ℕ be a sequence in [0, 1]d , {λn}n∈ℕ a sequence of positive real numbers converging to 0, and δ > 1. The classical ubiquity results are concerned with the computation of the Hausdorff dimension of limsup-sets of the form
Let μ be a positive Borel measure on [0, 1]d , ρ 2 (0, 1] and α > 0. Consider the finer limsup-set
We show that, under suitable assumptions on the measure μ, the Hausdorff dimension of the sets Sμ(ρ, δ, α) can be computed. Moreover, when ρ < 1, a yet unknown saturation phenomenon appears in the computation of the Hausdorff dimension of Sμ(ρ, δ, α). Our results apply to several classes of multifractal measures, and S(δ) corresponds to the special case where μ is a monofractal measure like the Lebesgue measure. The computation of the dimensions of such sets opens the way to the study of several new objects and phenomena. Applications are given for the Diophantine approximation conditioned by (or combined with) b-adic expansion properties, by averages of some Birkhoff sums and branching randomwalks, as well as by asymptotic behavior of random covering numbers.  相似文献   

15.
By using the continuation theorem of Mawhin's coincidence degree theory, a sufficient condition is derived for the existence of positive periodic solutions for a distributed delay competition modelwhere ri and r2 are continuous w-periodic functions in R+=[0,∞) with ,ai,ci(i =1,2) are positive continuous w-periodic functions in R+=[0,∞),bi (i = 1,2) is nonnegative continuous w-periodic function in R+=[0,∞), w and T are positive constants. Ki,Lt ∈ C([-T,0], (01 88)) and Ki(s)ds = 1,ds - 1. i = 1,2. Some known results are improved and extended.  相似文献   

16.
Let Δn−1 denote the (n − 1)-dimensional simplex. Let Y be a random 2-dimensional subcomplex of Δn−1 obtained by starting with the full 1-dimensional skeleton of Δn−1 and then adding each 2−simplex independently with probability p. Let denote the first homology group of Y with mod 2 coefficients. It is shown that for any function ω(n) that tends to infinity
* Supported by an Israel Science Foundation grant.  相似文献   

17.
Let p = (pk)k=0^∞ be a bounded sequence of positive reals, m C N and u be s sequence of nonzero terms. If x = (xk)k=0^∞ is any sequence of complex numbers we write Δ(m)x for the sequence of the m th order differences of x and Δu^(m)X = {x=(x)k=0^∞ uΔ(m)x ∈ X} for any set X of sequences. We determine the α-, β- and γ-duals of the sets Δμ^(m)X for X=co(p),c(p),l∞(p) and characterize some matrix transformations between these spaces Δ^(m)X.  相似文献   

18.
The factorization of the Laplacian by means of first order systems and of second order operators was considered by several authors (see, e.g [2],[3],[4]). In the paper the definition of Cauchy-Riemann system (CR-system) of ordern is given by their symbols. We prove that ifD (n) is the symbol andD (s, n) is the sign-matrix of CR-system, then
and
where Δ denotes teh Laplacian operator inR n. We show that(CN) n ≠ ϕ if and only ifn ∈ {2, 4, 8}. This work was supported in part by N.B.R.P in N.S. Vietnam  相似文献   

19.
Let H be a Hilbert space and A, B: HH two maximal monotone operators. In this paper, we investigate the properties of the following proximal type algorithm:
where (λ n ) is a sequence of positive steps. Algorithm may be viewed as the discretized equation of a nonlinear oscillator subject to friction. We prove that, if 0 ∈ int (A(0)) (condition of dry friction), then the sequence (x n ) generated by is strongly convergent and its limit x satisfies 0 ∈ A(0) + B(x ). We show that, under a general condition, the limit x is achieved in a finite number of iterations. When this condition is not satisfied, we prove in a rather large setting that the convergence rate is at least geometrical.  相似文献   

20.
Let Δ(x) denote the error term in the Dirichlet divisor problem, and E(T) the error term in the asymptotic formula for the mean square of . If with , then we obtain
. We also show how our method of proof yields the bound
, where T 1/5+εGT, T<t 1<...<t R ≤2T, t r +1t r ≥5G (r=1, ..., R−1).  相似文献   

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