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161.
Óscar Ciaurri 《Rendiconti del Circolo Matematico di Palermo》2004,53(2):231-234
A transference theorem for multipliers of Hermite expansions is proved. The result allows to transfer weightedL
2(ℝ
n
) estimates from lower to higher dimensions.
Research of the author supported by grant BFM2003-06335-603-03 of the D.G.I.. 相似文献
162.
H.?IshikawaEmail author J.?M.?ThuswaldnerEmail author 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》2004,74(1):11-32
Matsuoka showed an asymptotic formula for the coefficients of the Laurent expansion of ζ (s) at s = 1. In the present paper we extend this result to a large class of Dirichlet series which was first studied by Chandrasekharan
and Narasimhan. Our proofs are based on a saddle point argument and use the fact that the Dirichlet series under consideration
admit a functional equation.
The second author was supported by the FWF project S381O. 相似文献
163.
Let F (s) be a function belonging to the Selberg class. For a primitive Dirichlet character , we can define the -twist F(s) of F (s). If F(s) also belongs to the Selberg class and satisfies some other conditions then there is a relation between the zeros of F (s) and the zeros F(s). Further we give an operator theoretic interpretation of this relation according to A. Connes study.Received: 5 January 2004 相似文献
164.
Solutions are obtained for the stress state problem for an elastic space with an internal toroidalshaped cavity that can be expanded in a trigonometric series in the angle in cylindrical coordinates. Displacements and stresses are specified on the boundary. An analytic solution of the problem is found using generalized analytic functions. Stresses and displacements of points in the elastic space are calculated. 相似文献
165.
We establish a discrepancy theorem for signed measures, with a given positive part, which are supported on an arbitrary convex
curve. As a main application, we obtain a result concerning the distribution of zeros of polynomials orthogonal on a convex
domain. 相似文献
166.
M. I. Ganzburg 《Constructive Approximation》2001,17(2):275-306
We study Pólya-and Remez-type inequalities for univariate and multivariate polynomials and discuss their applications to Nikolskii-type
inequalities and upper estimates of trigonometric integrals. 相似文献
167.
It is shown that the m th-order derivative of the n th-order Bernstein polynomial of a function f satisfying a certain Lipschitz condition, can be written for n\rightarrow +∈fty as a singular integral of Gauss—Weierstrass type, m times differentiated (in a certain sense) under the integral sign. The theorem is applied to yield an overdifferentiation formula, involving p times differentiated Bernstein polynomials of functions that are not C
p
.
December 1, 1998. Dates revised: July 22, 1999 and January 11, 2000. Date accepted: February 1, 2000. 相似文献
168.
J. Yoon 《Constructive Approximation》2001,17(2):227-247
A new multivariate approximation scheme on R
d
using scattered translates of the “shifted” surface spline function is developed. The scheme is shown to provide spectral
L
p
-approximation orders with 1 ≤ p ≤ ∞, i.e., approximation orders that depend on the smoothness of the approximands. In addition, it applies to noisy data
as well as noiseless data. A numerical example is presented with a comparison between the new scheme and the surface spline
interpolation method. 相似文献
169.
Let (X, F) be an Alexandroff space, let A(F) be the Boolean subalgebra of 2
X
generated by F, let G be a Hausdorff commutative topological lattice group and let rbaF(A(F), G) denote the set of all order bounded F-inner regular finitely additive set functions from A(F) into G. Using some special properties of the elements of rbaF(A(F), G), we extend to this setting the first decomposition theorem of Alexandroff. 相似文献
170.
Ole Christensen 《Journal of Fourier Analysis and Applications》2000,6(1):79-91
A frame in a Hilbert space
allows every element in
to be written as a linear combination of the frame elements, with coefficients called frame coefficients. Calculations of
those coefficients and many other situations where frames occur, requires knowledge of the inverse frame operator. But usually
it is hard to invert the frame operator if the underlying Hilbert space is infinite dimensional. In the present paper we introduce
a method for approximation of the inverse frame operator using finite subsets of the frame. In particular this allows to approximate
the frame coefficients (even inl
2) using finite-dimensional linear algebra. We show that the general method simplifies in the important cases of Weil-Heisenberg
frames and wavelet frames. 相似文献