一类二元半正交小波包的构造

本文给出伸缩矩阵行列式为2的一类二元半正交小波包的构造算法.该小波包是以频域给出的,随着用于小波包分裂的滤波器选取的不同会得到L2(R2)中形态各异的Riesz基,这样使得L2(R2)中小波基的选择更灵活.     

r重非正交小波包

该文讨论了由有限个尺度函数｛φ1，φ2，…，φr｝所生成的L2（R）上的多分辨分析．并考虑了L2（R）上直接小波分解和直接小波包分解，对（对偶）非正交小波包以及产生它们的基的稳定性作了较为深人的研究，获得了一些结果．     

一类二维不可分非正交小波包

Zuowei Shen构造了L^2（R^s)空间的二进制小泡包,与伸缩矩阵M＝（1 1 1 －1）相关的小波适用于二维图像处理中的梅花状子取样,本文给出了一种构造非正交M－小滤包的方法。     

Construction of Multivariate Tight Framelet Packets Associated with Dilation Matrix

In this paper, we present a method for constructing multivariate tight framelet packets associated with an arbitrary dilation matrix using unitary extension principles.We also prove how to construct various tight frames for L2(Rd) by replac-ing some mother framelets.     

矩阵伸缩的高维向量值小波包

本文给出了对应于任意整数矩阵伸缩的高维向量值正交小波包的定义及其构造方法．并讨论了这种向量值正交小波包的性质,得到向量值函数空间L2(Rs,Cr)的新的正交小波基．     

向量值正交小波的构造与向量值小波包的特征

The notion of vector-valued multiresolution analysis is introduced and the concept of orthogonal vector-valued wavelets with 3-scale is proposed.A necessary and sufficient condition on the existence of orthogonal vector-valued wavelets is given by means of paraunitary vector filter bank theory.An algorithm for constructing a class of compactly supported orthogonal vector-valued wavelets is presented.Their characteristics is discussed by virtue of operator theory,time-frequency method.Moreover,it is shown how to design various orthonormal bases of space L2(R,Cn) from these wavelet packets.     

Wavelet packets associated with nonuniform multiresolution analyses

A multiresolution analysis was defined by Gabardo and Nashed for which the translation set is a discrete set which is not a group. We construct the associated wavelet packets for such an MRA. Further, from the collection of dilations and translations of the wavelet packets, we characterize the subcollections which form orthonormal bases for L²(R).     

Wavelet frames and shift-invariant subspaces of periodic functions

A general approach based on polyphase splines, with analysis in the frequency domain, is developed for studying wavelet frames of periodic functions of one or higher dimensions. Characterizations of frames for shift-invariant subspaces of periodic functions and results on the structure of these subspaces are obtained. Starting from any multiresolution analysis, a constructive proof is provided for the existence of a normalized tight wavelet frame. The construction gives the minimum number of wavelets required. As an illustration of the approach developed, the one-dimensional dyadic case is further discussed in detail, concluding with a concrete example of trigonometric polynomial wavelet frames.     

Wavelet bases on a manifold

Using the decomposition method, we present in this paper constructions of multiresolution analyses on a compact Riemannian manifold M of dimension n(n∈N). These analyses are generated by a finite number of basic functions and are adapted to the study of the Sobolev spaces H¹(M) and .     

On a class of bidimensional nonseparable wavelet multipliers

Let

A measurable function v is called an E-wavelet multiplier if is an E-wavelet whenever ψ is an E-wavelet. In this paper, some characterizations of E-wavelet multiplier are obtained. As an application of these techniques, we prove that the set of E-wavelets is arcwise connected.     

小波包变换及代价函数设计综述

小波包是小波理论的重要组成部分,在非平稳信号特征检测和故障诊断中具有广泛的应用。小波包教学是小波分析教学的一个难点,也是一个较容易忽视的知识点。本文分析了小波包理论,归纳总结了小波包目标函数,以及它们适用的领域,并提出了新的目标函数。本文可以对小波包的教学提供一些新的思路。     

A Class of Orthogonal Refinable Functions and Wavelets

We give a construction, for any n 2, of a space S of spline functions of degree n – 1 with simple knots in (1/4)Z which is generated by a triple of refinable, orthogonal functions with compact support. Indeed, the result holds more generally by replacing the B-spline of degree n – 1 with simple knots at the integers by any continuous refinable function whose mask is a Hurwitz polynomial of degree n. A simple construction is also given for the corresponding wavelets.     

具有特殊伸缩矩阵的Parseval框架小波集的结构

揭示具有特殊伸缩矩阵的Parseval框架小波集的丰富结构.借助于平移不变空间和维数函数,研究了具有特殊伸缩矩阵M的Parseval框架小波(M-PFW)、半正交M-PFW和MRA M-PFW的各种性质,探讨了M-PFW集合的各种子类,给出了这些子类的构造性算例.     

α带小波紧框架的显式构造方法

文中研究了对应于α-带尺度函数的小波紧框架,这个小波紧框架是由V₁中的n个函数ψ¹,ψ²,...,ψⁿ构成. 首先给出了这n个函数构成小波紧框架的充分条件, 并借助尺度函数给出了构造小波紧框架的显式公式. 如果尺度函数的符号是有理函数,则可以构造出符号为有理函数的小波紧框架. 其次给出类似于正交小波的小波紧框架的分解与重构算法,并构造了小波紧框架的数值算例.     

正交小波包的构造

本文给出尺度因子ａ＝４时正交小波包的构造，推广了［２，４］引入的正交小波包，并给出相应的分解与再构造算法．本文引入的正交小波包具有保持信号ｆ∈Ｌ^２的线性相位，也讨论了尺度因子ａ＝ｋ（ｋ∈Ｚ，ｋ≥２）正交小波的构造     

Fast Wavelet Transform for Toeplitz Matrices and Property Analysis

Fast wavelet transform algorithms for Toeplitz matrices are proposed in this paper. Distinctive from the well known discrete trigonometric transforms, such as the discrete cosine transform （DCT） and the discrete Fourier transform （DFT） for Toeplitz matrices, the new algorithms are achieved by compactly supported wavelet that preserve the character of a Toeplitz matrix after transform, which is quite useful in many applications involving a Toeplitz matrix. Results of numerical experiments show that the proposed method has good compression performance similar to using wavelet in the digital image coding. Since the proposed algorithms turn a dense Toeplitz matrix into a band-limited form, the arithmetic operations required by the new algorithms are O（N） that are reduced greatly compared with O（N log N） by the classical trigonometric transforms.     

L~2[0,1]上的正交小波基

从尺度因子 M =4的正交小波基出发 ,利用折叠方法得到了 L 2 [0 ,1 ]空间的正交小波基 .这种小波不同于折叠前的小波基 ,它是完全限制在有限区间 [0 ,1 ]上 ,且保持小波基的正交性 ,并在使用过程中拥有更大的灵活性 .也可用类似方法对一般尺度小波进行折叠     

Symmetric and antisymmetric tight wavelet frames

For a given set of wavelets Ψ, we provide a general, and yet simple, method to derive a new set of wavelets ${\Psi }^{\prime }$ such that each wavelet in ${\Psi }^{\prime }$ is either symmetric or antisymmetric. The affine system generated by ${\Psi }^{\prime }$ is a tight frame for the space $L_2({\mathbb{R}}^d)$ whenever the affine system generated by Ψ is so. Further, when Ψ is constructed via a multiresolution analysis, ${\Psi }^{\prime }$ can also be derived from a, but possibly different, multiresolution analysis. If moreover the multiresolution analysis for constructing Ψ is generated by a symmetric refinable function, then ${\Psi }^{\prime }$ is obtained from the same multiresolution analysis.     

一类d-disjunct矩阵的构作方法

(d,r)-disjunct矩阵、(d,r,z)-disjunct矩阵、(d,r,z]-disjunct矩阵等是一类d-disjunct矩阵,它们比d-disjunct矩阵有着更为广泛的应用.介绍了这一类d-disjunct矩阵的一种简单构作方法,并计算了它的参数.