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1.
We obtain, for T ε U=U(T)≤T 1/2−ε , asymptotic formulas for
where Δ(x) is the error term in the classical divisor problem, and E(T) is the error term in the mean square formula for . Upper bounds of the form O ε (T 1+ε U 2) for the above integrals with biquadrates instead of square are shown to hold for T 3/8U=U(T) T 1/2. The connection between the moments of E(t+U)−E(t) and is also given. Generalizations to some other number-theoretic error terms are discussed.   相似文献   

2.
Statistical properties of continued fractions for numbers a/b, where a and b lie in the sector a, b ≥ 1, a2 + b2 ≤ R2, are studied. The main result is an asymptotic formula with two meaning terms for the quantity
where sx(a/b) = |{j ε {1, …, s}: [0; tj, …, ts] ≤ x}| is the Gaussian statistic for the fraction a/b = [t0; t1, …, ts]. Bibliography: 12 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 322, 2005, pp. 186–211.  相似文献   

3.
Consider a stochastic process {X t , 0 ≤ tT} governed by a stochastic differential equation given by
dXt = S(Xt)   dt + e  dWtH,    X0=x0,    0 £ tT dX_t= S(X_t) \;dt + \epsilon \; dW_t^H,\quad X_0=x_0,\quad 0 \leq t \leq T  相似文献   

4.
Let T(t), t ≥ 0, be a C 0-semigroup of linear operators acting in a Hilbert space H with norm ‖·‖. We prove that T(t) is uniformly bounded, i.e., ‖T(t)‖ ≤ M, t ≥ 0, if and only if the following condition is satisfied:
, where T* is the adjoint operator. __________ Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 6, pp. 853–858, June, 2007.  相似文献   

5.
In this paper the forced neutral difterential equation with positive and negative coefficients d/dt [x(t)-R(t)x(t-r)] P(t)x(t-x)-Q(t)x(t-σ)=f(t),t≥t0,is considered,where f∈L^1(t0,∞)交集C([t0,∞],R^ )and r,x,σ∈(0,∞),The sufficient conditions to oscillate for all solutions of this equation are studied.  相似文献   

6.
In this work we prove a new strong convergence result of the regularized successive approximation method given by yn+1 = qnz0 + (1 - qn)T^nyn, n = 1, 2,…,where lim n→∞ qn = 0 and ∞∑n=1 qn=∞ for T a total asymptotically nonexpansive mapping, i.e., T is such that
││T^n x - T^n y││ ≤ x - y ││ + kn^(1)φ(││x - y││) + kn^(2),where kn^1 and kn^2 are real null convergent sequences and φ:R^+→R^+ is continuous such that φ(0)=0 and limt→∞φ(t)/t≤ C for a certain constant C 〉 0.
Among other features, our results essentially generalize existing results on strong convergence for T nonexpansive and asymptotically nonexpansive. The convergence and stability analysis is given for both self- and nonself-mappings.  相似文献   

7.
LetA be the class of normalized analytic functions in the unit disk Δ and define the class
For a functionf εA the Alexander transformF 0 is given by
Our main object is to establish a sharp relation betweenβ andγ such thatf εP β implies thatF 0 is starlike of orderγ, 0 ≤γ ≤ 1/2. A corresponding result for the Libera transformF 1(z) = 2∫ 0 1 f(tz)dt is also given.  相似文献   

8.
Let (M,g(t)), 0 ≤ tT, be an n-dimensional closed manifold with nonnegative Ricci curvature, |Rc| ≤ C/t for some constant C > 0 and g(t) evolving by the Ricci flow
$\frac{{\partial g_{ij} }} {{\partial t}} = - 2R_{ij} . $\frac{{\partial g_{ij} }} {{\partial t}} = - 2R_{ij} .   相似文献   

9.
The solvability of the boundary-value problem
in the space H 0 2 (0, 1) is proved under the following assumptions: p0(t)t3(1 − t)3 ∈ L(0, 1), p1(t)t(1 − t) ∈ L(0, 1), f(t)t3/2(1 − t)3/2 ∈ L(0, 1), 0 ≤ p2(t)[t(1 − t)]k+1 ∈ L(0, 1), 0 ≤ f0(t)[t(1 − t)]3/2 ∈ L(0, 1), 0 ≤ f1(t)[t(1 − t)]3m+3 ∈ L(0, 1), ϕ(u)u ≥ −c|u|, c > 0,
. Bibliography: 6 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 334, 2006, pp. 233–245.  相似文献   

10.
In the present paper, we derive the Laplace transforms of the integral functionals
and
where p and q are real numbers, {B t (μ) : t ≥ 0} is a Brownian motion with drift μ > 0 (denoted BM(μ)), and {R t (3) : t ≥ 0} is a 3-dimensional Bessel process (denoted BES(3)). The transforms are given in terms of Gauss' hypergeometric functions, and the results are closely related to some results for functionals of Jacobi diffusions. This work generalizes and completes some results of Donati-Martin and Yor and Salminen and Yor. Bibliography: 18 titles. __________ Published in Zapiski Nauchnykh Seminarov POMI, Vol. 311, 2004, pp. 51–78.  相似文献   

11.
We consider the following singularly perturbed boundary-value problem:
on the interval 0 ≤x ≤ 1. We study the existence and uniqueness of its solutionu(x, ε) having the following properties:u(x, ε) →u 0(x) asε → 0 uniformly inx ε [0, 1], whereu 0(x) εC [0, 1] is a solution of the degenerate equationf(x, u, u′)=0; there exists a pointx 0 ε (0, 1) such thata(x 0)=0,a′(x 0) > 0,a(x) < 0 for 0 ≤x <x 0, anda(x) > 0 forx 0 <x ≤ 1, wherea(x)=f′ v(x,u 0(x),u′ 0(x)). Translated fromMatematicheskie Zametki, Vol. 67, No. 4, pp. 520–524, April, 2000.  相似文献   

12.
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   

13.
For families of processes with independent increments (t), 0tT, with frequent small jumps, limit theorems for expectations of the functionals F([0, T]) are proved of the form where diD, are positive numbers, A di are linear integro-differential or differential operators acting on functionals, and some differentiability conditions are imposed on the functional F. The case of power tails of the jump distribution is considered.Mathematics Subject Classification (2000):60F17  相似文献   

14.
 Let Y=(X,{R i }0≤i≤D) denote a symmetric association scheme with D≥3, and assume Y is not an ordinary cycle. Suppose Y is bipartite P-polynomial with respect to the given ordering A 0, A 1,…, A D of the associate matrices, and Q-polynomial with respect to the ordering E 0, E 1,…,E D of the primitive idempotents. Then the eigenvalues and dual eigenvalues satisfy exactly one of (i)–(iv). (i)
(ii) D is even, and
(iii) θ* 00, and
(iv) θ* 00, D is odd, and
Received: February 13, 1996 / Revised: October 16, 1996  相似文献   

15.
We describe sequences of zeros of functionsf≢0 that are analytic in the half-plane ℂ+={z:Rez> and satisfy the condition
where 0≤σ<+∞ and η is a positive function continuously differentiable on [0; +∞) and such thatxη′(x)/η(x)→0 asx→+∞. Drohobych Pedagogic University, Drohobych. Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 51, No. 7, pp. 904–909, July, 1999.  相似文献   

16.
WEIGHTEDAPPROXIMATIONOFRANDOMFUNCTIONSYUJIARONGAbstract:Let(Ω,A,P)beaprobabilityspace,X(t,ω)arandomfunctioncontinuousinprobab...  相似文献   

17.
This paper deals with the blow-up properties of solutions to a system of heat equations u tu, v tv in B R×(0, T) with the Neumann boundary conditions εu/εη=e v, εv/εη=e u on S R×[0, T). The exact blow-up rates are established. It is also proved that the blow-up will occur only on the boundary. This work is supported by the National Natural Science Foundation of China  相似文献   

18.
The behavior on the space L∞((R)n) for the multilinear singular integral operator defined by TAf(x)=∫Rn Ω(x-y)/|x-y|n 1(A(x)-A(y)-(△)A(y)(x-y))f(y)dy is considered, where Ω is homogeneous of degree zero, integrable on the unit sphere and has vanishing moment of order one, A has derivatives of order one in BMO((R)n). It is proved that if Ω satisfies some minimum size condition and an L1-Dini type regularity condition, then for f ∈ L∞((R)n), TAf is either infinite almost everywhere or finite almost everywhere, and in the latter case, TAf ∈ BMO((R)n).  相似文献   

19.
Let II be a bounded symmetric domain, ω ⇉ I a bounded subdomain, and let denote the weighted Bergman space of holomorphic square integrable functions on I. Let Tλ, ω be the Berezin-Toeplitz operator on with symbol χΩ and kth eigenvalue λ k (T λ,Ω). We prove that for δ1 sufficiently close to 0 and δ2 sufficiently close to 1 the estimate
holds for all domains ω satisfying the condition |{z ∈ I |d(z, Ω) < ε}| ≤c|Ω|, where d is the invariant distance on I and |ω| is the invariant volume of ω. The proof is based on the fact that the operator norm of the Berezin transform is smaller than 1. Our main technical tool are some of the formulae for the Berezin transform obtained by Unterberger and Upmeier in [11].  相似文献   

20.
ANOTEONTHEBEHAVIOROFBLOW┐UPSOLUTIONSFORONE┐PHASESTEFANPROBLEMSZHUNINGAbstract.Inthispaper,thefolowingone-phaseStefanproblemis...  相似文献   

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