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1.
X(t) (t∉[0,∞)) is a subordinator with its upper index β less than one, g(u) is the index function ofX(t), andX(t), andX[0,1]={xϕR:X(t)=x} for sometϕ[0,1]{. If φ(s)(sϕ(0,1)) is a measure function andh , then
. The packing dimension ofX (t) is the uppcr index β. Project supported by the Natural Science Foundation of Zhejiang Province.  相似文献   

2.
Let X, X1, X2,... be i.i.d, random variables with mean zero and positive, finite variance σ^2, and set Sn = X1 +... + Xn, n≥1. The author proves that, if EX^2I{|X|≥t} = 0((log log t)^-1) as t→∞, then for any a〉-1 and b〉 -1,lim ε↑1/√1+a(1/√1+a-ε)b+1 ∑n=1^∞(logn)^a(loglogn)^b/nP{max κ≤n|Sκ|≤√σ^2π^2n/8loglogn(ε+an)}=4/π(1/2(1+a)^3/2)^b+1 Г(b+1),whenever an = o(1/log log n). The author obtains the sufficient and necessary conditions for this kind of results to hold.  相似文献   

3.
For given 2n×2n matricesS 13,S 24 with rank(S 13,S 24)=2n we consider the eigenvalue problem:u′=A(x)u+B(x)v,v′=C 1(x;λ)u-A T(x)v with
  相似文献   

4.
The following regularity of weak solutions of a class of elliptic equations of the form are investigated.  相似文献   

5.
The distributionF(x +, −r) Inx+ andF(x , −s) corresponding to the functionsx + −r lnx+ andx −s respectively are defined by the equations
(1) and
(2) whereH(x) denotes the Heaviside function. In this paper, using the concept of the neutrix limit due to J G van der Corput [1], we evaluate the non-commutative neutrix product of distributionsF(x +, −r) lnx+ andF(x , −s). The formulae for the neutrix productsF(x +, −r) lnx + ox −s, x+ −r lnx+ ox −s andx −s o F(x+, −r) lnx+ are also given forr, s = 1, 2, ...  相似文献   

6.
Let f∈C [−1,1] (r≥1) and Rn(f,α,β,x) be the generalized Pál interpolation polynomials satisfying the conditions Rn(f,α,β,xk)=f(xk),Rn (f,α,β,xk)=f′(xk)(k=1,2,…,n), where {xk} are the roots of n-th Jacobi polynomial Pn(α,β,x),α,β>−1 and {x k } are the roots of (1−x2)Pn″(α,β,x). In this paper, we prove that holds uniformly on [0,1]. In Memory of Professor M. T. Cheng Supported by the Science Foundation of CSBTB and the Natural Science Foundatioin of Zhejiang.  相似文献   

7.
1. IntroductionIt is a useful and challenging task to find efficient algorithms for many computationalhard problems. Recently, the research on Fixed-Parameter nactable Theory arouses muchinterest. FOr example, different fixed- p ax amet er- t rac t ab le- algori t hms for many well- knowndecisio11 pruble11ls illc1udi11g 3-dimellsio11al IIlatchiIlg: a11d vertex--cover Problen1 have beenPrese11ted in [1 8]. Jia11er Chen, DoIlald K. FYiesen al1d Weijia Jia proPosed a coll1pletelynew appro…  相似文献   

8.
Carleman estimates for one-dimensional degenerate heat equations   总被引:1,自引:0,他引:1  
In this paper, we are interested in controllability properties of parabolic equations degenerating at the boundary of the space domain. We derive new Carleman estimates for the degenerate parabolic equation $$ w_t + \left( {a\left( x \right)w_x } \right)_x = f,\quad \left( {t,x} \right) \in \left( {0,T} \right) \times \left( {0,1} \right), $$ where the function a mainly satisfies $$ a \in \mathcal{C}^0 \left( {\left[ {0,1} \right]} \right) \cap \mathcal{C}^1 \left( {\left( {0,1} \right)} \right),a \gt 0 \hbox{on }\left( {0,1} \right) \hbox{and }\frac{1} {{\sqrt a }} \in L^1 \left( {0,1} \right). $$ We are mainly interested in the situation of a degenerate equation at the boundary i.e. in the case where a(0)=0 and / or a(1)=0. A typical example is a(x)=xα (1 − x)β with α, β ∈ [0, 2). As a consequence, we deduce null controllability results for the degenerate one dimensional heat equation $$ u_t - (a(x)u_x )_x = h\chi _w ,\quad (t,x) \in (0,T) \times (0,1),\quad \omega \subset \subset (0,1). $$ The present paper completes and improves previous works [7, 8] where this problem was solved in the case a(x)=xα with α ∈[0, 2). Dedicated to Giuseppe Da Prato on the occasion of his 70th birthday  相似文献   

9.
We consider the weighted Hardy integral operatorT:L 2(a, b) →L 2(a, b), −∞≤a<b≤∞, defined by . In [EEH1] and [EEH2], under certain conditions onu andv, upper and lower estimates and asymptotic results were obtained for the approximation numbersa n(T) ofT. In this paper, we show that under suitable conditions onu andv, where ∥wp=(∫ a b |w(t)|p dt)1/p. Research supported by NSERC, grant A4021. Research supported by grant No. 201/98/P017 of the Grant Agency of the Czech Republic.  相似文献   

10.
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   

11.
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   

12.
LetX 1,X 2, ...,X n be a sequence of nonnegative independent random variables with a common continuous distribution functionF. LetY 1,Y 2, ...,Y n be another sequence of nonnegative independent random variables with a common continuous distribution functionG, also independent of {X i }. We can only observeZ i =min(X i ,Y i ), and . LetH=1−(1−F)(1−G) be the distribution function ofZ. In this paper, the limit theorems for the ratio of the Kaplan-Meier estimator or the Altshuler estimator to the true survival functionS(t) are given. It is shown that (1)P(n)=1 i.o.)=0 ifF H ) < 1 andP n =0 i.o. )=0 ifGH) > 1 where δ(n) is the corresponding indicator function of and have the same order a.s., where {T n } is a sequence of constants such that 1−H(T n )=n −α(logn)β(log logn)γ.  相似文献   

13.
The paper proves that, if f(x) ∈ L^p[-1,1],1≤p〈∞ ,changes sign I times in (-1, 1),then there exists a real rational function r(x) ∈ Rn^(2μ-1)l which is eopositive with f(x), such that the following Jackson type estimate ||f-r||p≤Cδl^2μωφ(f,1/n)p holds, where μ is a natural number ≥3/2+1/p, and Cδ is a positive constant depending only on δ.  相似文献   

14.
For any a,b∈R let ϕa,b(x)=ax+b(x∈R). Suppose 0<a<1. Let Ca,b be the generalized a-Cantor set with generating iterated function systme {ϕa,0, ϕa,b; ϕa,l}. Then we prove the Hausdorff dimension of Ca,c2 C_{a,c^2 } is \fracln(3 - ?5 - ln2lna\frac{{ln(3 - \sqrt 5 - ln2}}{{lna}} when 0<a≤2 cos 80°.  相似文献   

15.
Let Sk(Γ) be the space of holomorphic Γ-cusp forms f(z) of even weight k ≥ 12 for Γ = SL(2, ), and let Sk(Γ)+ be the set of all Hecke eigenforms from this space with the first Fourier coefficient af(1) = 1. For f ∈ Sk(Γ)+, consider the Hecke L-function L(s, f). Let
It is proved that for large K,
where ε > 0 is arbitrary. For f ∈ Sk(Γ)+, let L(s, sym 2 f) denote the symmetric square L-function. It is proved that as k → ∞ the frequence
converges to a distribution function G(x) at every point of continuity of the latter, and for the corresponding characteristic function an explicit expression is obtained. Bibliography: 17 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 314, 2004, pp. 221–246.  相似文献   

16.
Summary In this paper we determine all orthogonal polynomials Un(x) such that Un(x)=x1/2 F 2n+1 (x 1/2 ) and where f(t), u(t) have Taylor series expansions. Supported in part by N. S. F. grant GP-1593.  相似文献   

17.
Assuming a quasi Generalized Riemann Hypothesis (quasi-GRH for short) for Dedekind zeta functions over Kummer fields of the type we prove the following prime analogue of a conjecture of Erd?s & Pomerance (1985) concerning the exponent function fa(p) (defined to be the minimal exponent e for which ae ≡ 1 modulo p):
((‡))
where
The main result is obtained by computing all the higher moments corresponding to ω(fa(p)), and by comparing them, via the Fréchet-Shohat theorem, with estimates due to Halberstam concerning the moments of ω(p − 1). Received: 25 October 2004; revised: 12 February 2005  相似文献   

18.
Recently, Girstmair and Schoissengeier studied the asymptotic behavior of the arithmetic mean of Dedekind sums \frac1j(N) ? 0 £ m < Ngcd(m,N)=1 |S(m,N)|\frac{1}{\varphi(N)} \sum_{\mathop{\mathop{ 0 \le m< N}}\limits_{\gcd(m,N)=1}} \vert S(m,N)\vert , as N → ∞. In this paper we consider the arithmetic mean of weighted differences of Dedekind sums in the form Ah(Q)=\frac1?\fracaq ? FQh(\fracaq) ×?\fracaq ? FQh(\fracaq) |s(a,q)-s(a,q)|A_{h}(Q)=\frac{1}{\sum_{\frac{a}{q} \in {\cal F}_{Q}}h\left(\frac{a}{q}\right)} \times \sum_{\frac{a}{q} \in {\cal F}_{\!Q}}h\left(\frac{a}{q}\right) \vert s(a^{\prime},q^{\prime})-s(a,q)\vert , where h:[0,1] ? \Bbb Ch:[0,1] \rightarrow {\Bbb C} is a continuous function with ò01 h(t)  d t 1 0\int_0^1 h(t) \, {\rm d} t \ne 0 , \fracaq{\frac{a}{q}} runs over FQ{\cal F}_{\!Q} , the set of Farey fractions of order Q in the unit interval [0,1] and \fracaq < \fracaq{\frac{a}{q}}<\frac{a^{\prime}}{q^{\prime}} are consecutive elements of FQ{\cal F}_{\!Q} . We show that the limit lim Q→∞ A h (Q) exists and is independent of h.  相似文献   

19.
Summary LetS i have the Wishart distributionW p(∑i,ni) fori=1,2. An asymptotic expansion of the distribution of for large n=n1+n2 is derived, when 12 −1 =I+n−1/2θ, based on an asymptotic solution of the system of partial differential equations for the hypergeometric function2 F 1, obtained recently by Muirhead [2]. Another asymptotic formula is also applied to the distributions of −2 log λ and −log|S 2(S 1+S 2)−1| under fixed 12 −1 , which gives the earlier results by Nagao [4]. Some useful asymptotic formulas for1 F 1 were investigated by Sugiura [7].  相似文献   

20.
In this paper, the relationship between the s-dimensional Hausdorff measures and the g-measures in Rd is discussed, where g is a gauge function which is equivalent to ts and 0 < s≤d. It shows that if s=d, then Hg = c1Hd, Cg = c2Cd and Pg = c3Pd on Rd, where constants c1, c2 and c3 are determined by where Wg, Cg and Pg are the g-Hausdorff, g-central Hausdorff and g-packing measures on Rd respectively. In the case 0相似文献   

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