Paley–Wiener–Schwartz type theorem for the wavelet transform

In the present paper, we discuss about extension of the wavelet transform on distribution space of compact support and develop the Paley–Wiener–Schwartz type theorem for the wavelet transform on the same. Furthermore, Paley–Wiener–Schwartz type theorem for the wavelet transform is also established using the relation between the wavelet transform and double Fourier transform.     

On solvability of one nonlinear integral equation in the class of analytic functions

We consider a nonlinear integral equation of a special type that appears in the inverse spectral theory of integro-differential operators and whose unique solvability in the class of square-integrable functions is known. However, for some applied issues in order to construct effective algorithms for solving equations of this type, it is required to establish their solvability in the class of analytic functions. Assuming the free term of the nonlinear equation under consideration to be an entire function of exponential type, we prove that so is its solution. Leaning on this result we provide a constructive procedure for solving this equation in the class of square-integrable functions, which can be easily implemented numerically.     

错误数据集的变换研究

首先介绍错误数据集C的定义;再者引出错误数据集合的变换,最后研究各类错误数据集的有关运算及这些运算所满足的运算律.得出错误数据集的变换包括逆、或、积;错误集的变换类型有7种包括单位变换、置换变换、分解变换、组合变换、毁灭变换、增加变换、相似变换.     

Continuity of the fractional Hankel wavelet transform on the spaces of type S

In this present article, we study the fractional Hankel transform and its inverse on certain Gel'fand‐Shilov spaces of type S. The continuous fractional wavelet transform is defined involving the fractional Hankel transform. The continuity of fractional Hankel wavelet transform is discussed on Gel'fand‐Shilov spaces of type S. This article goes further to discuss the continuity property of fractional Hankel transform and fractional Hankel wavelet transform on the ultradifferentiable function spaces.     

离散余弦变换的一种推广

离散余弦变换(DCT)在数字信号、图像处理、频谱分析、数据压缩和信息隐藏等领域有着广泛的应用.推广离散余弦变换,给出一个包含三个参数的统一表达式,并证明在许多情形新变换是正交变换.最后给出一种新型离散余弦变换,并证明它是正交变换.     

On the index integral transformation with Nicholson's function as the kernel

The integral transformation, which is associated with the Nicholson function as the kernel, is introduced and investigated in the paper. This transformation is an integral, where integration is with respect to an index of the sum of squares of Bessel functions of the first and second kind. Composition representations and relationships with the Meijer K-transform, the Kontorovich-Lebedev transform, the Mellin transform, and the sine Fourier transform are given. We also present boundedness properties, a Parseval type equality, and an inversion formula.     

Integral transformations by the index of Lommel's function

In this paper we study a class of integral transformations with kernels consisting of Lommel's functions of a certain index. Boundedness properties, Parseval type formula, inversion theorem are proved in Lebesgue spaces of integrable functions. This revised version was published online in August 2006 with corrections to the Cover Date.     

On an αth-order fractional Radon transform and a wave type of equation

The Fourier slice theorem holds for the classical Radon transform. In this paper, we consider a fractional Radon transform for which a sort of Fourier slice theorem also holds, and then present an inversion formula. The fractional Radon transform is shown to be characterized by the multi-dimensional case of a wave type of equation in analogy to the classical Radon transform.     

Integrals involving products of Airy functions, their derivatives and Bessel functions

A new integral representation of the Hankel transform type is deduced for the function Fn(x,Z)=Zn−1Ai(x−Z)Ai(x+Z) with x∈R, Z>0 and n∈N. This formula involves the product of Airy functions, their derivatives and Bessel functions. The presence of the latter allows one to perform various transformations with respect to Z and obtain new integral formulae of the type of the Mellin transform, K-transform, Laplace and Fourier transform. Some integrals containing Airy functions, their derivatives and Chebyshev polynomials of the first and second kind are computed explicitly. A new representation is given for the function ²|Ai(z)| with z∈C.     

Remarks on the degenerate Radon transform in

The aim of this note is to prove endpoint boundedness of the generalized Radon transform which was introduced by Phong and Stein. M. Christ's combinatorial method is used to obtain restricted weak type at the endpoints. Also we show that the results of this note are essentially optimal.

     

一维连续小波变换

1引言小波分析是近年来迅速发展起来的一门新兴学科,小波分析最显著的特征是频域和时域具有良好局部化特性,可以观察函数的任意细节,被誉为数学的显微镜．它不仅理论深刻,且理论与应用的发展交织在一起,它成功地应用于信噪分离、图像编码、图像的边缘检测、数据压缩、计算机视觉中的多分辨率分析等领域．     

A Class of Index Transforms with General Kernels

This paper deals with a class of integral transforms of the non - convolution type involving sufficiently general kernels, which depend upon two essentially independent arguments. One of them, in various particular cases, is a parameter or index of the corresponding special functions. This class of integral transforms comprises the famous Kontorovich-Lebedev and Mehler-Fock transforms. We study here the mapping properties and give also inversion theorems of the general index transforms on the space L_p(?), p ≥ 1, that covers the respective measurable functions on the whole real axis with the norm It is shown that the images of the transforms belong to the space L_{ν, p}(?₊), νε ?, 1 ≤ p ≤ ∞ of functions normed by In particular, when v = 1/p we get the usual L_p(?₊) space. We also direct our attention to the case of the Hilbert space and give certain interesting examples of these transforms.     

On the boundedness result of wavelet transform associated with fractional Hankel transform

This article is concerned with the study of the continuity of wavelet transform involving fractional Hankel transform on certain function spaces. The n-dimensional boundedness property of the fractional wavelet transform is also discussed on Sobolev type space. Particular cases are also considered.     

Another Grüss Type Inequality for Sequences of Vectors in Normed Linear Spaces and Applications

A discrete inequality of Grüss type in normed linear spaces and applications for the Fourier transform, Mellin transform of sequences, for polynomials with coefficients in normed spaces and for vector valued Lipschitzian mappings, are given.     

Characterizations of the Gelfand-Shilov spaces via Fourier transforms

We give symmetric characterizations, with respect to the Fourier transformation, of the Gelfand-Shilov spaces of (generalized) type and type . These results explain more clearly the invariance of these spaces under the Fourier transformations.

     

Dirichlet空间上Toeplitz算子与Berezin型变换相关的一些性质

本文研究了单位圆盘D 的Dirichlet 空间上Toeplitz 算子和小Hankel 算子. 利用Berezin 型变换讨论了Toeplitz 算子的不变子空间问题, 具有Berezin 型符号的Toeplitz 算子的渐进可乘性以及Toeplitz 算子的Riccati 方程的可解性. 应用Berezin 变换得到了Toeplitz 算子和小Hankel 算子可逆的充分条件. 此外, 还利用Hankel 算子和Berezin 变换刻画了算子2T_uv-T_uT_v-T_vT_u 的紧性, 其中函数u,v ∈ L^2,1.     

关于一类数学物理反问题的解

本文通过构造迭代序列，研究了抛物型偏微分方程的一类反问题的解，并推广了文［１］的结果     

Laplace-Stieltjes变换所定义的解析函数的精确型

In present paper, we study precisely the growth of analytic functions defined by zero order Laplace-Stieltjes transformation converging in right plane. The coefficient characterizations of generalized logarithmic p-type and generalized lower logarithmic p-type are obtained, which improve the results of logarithmic type and lower logarithmic type.     

Windowed Fourier transform of two-dimensional quaternionic signals

In this paper, we generalize the classical windowed Fourier transform (WFT) to quaternion-valued signals, called the quaternionic windowed Fourier transform (QWFT). Using the spectral representation of the quaternionic Fourier transform (QFT), we derive several important properties such as reconstruction formula, reproducing kernel, isometry, and orthogonality relation. Taking the Gaussian function as window function we obtain quaternionic Gabor filters which play the role of coefficient functions when decomposing the signal in the quaternionic Gabor basis. We apply the QWFT properties and the (right-sided) QFT to establish a Heisenberg type uncertainty principle for the QWFT. Finally, we briefly introduce an application of the QWFT to a linear time-varying system.     

一类抛物型偏微分方程反问题的稳定性

本文讨论一类抛物型偏微分方程反问题，研究测量值在特定边界上给定时源项确定的稳定性，在合理的假设下证明了该反问题具有按Ｌｉｐｓｃｈｉｔｚ型连续依赖于测量值的稳定性，推广了Ｙａｍａｍｏｔｏ的结果．