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Approximation properties of wavelets and relations among scaling moments II

Václav Finěk — 2004

Open Mathematics

A new orthonormality condition for scaling functions is derived. This condition shows a close connection between orthonormality and relations among discrete scaling moments. This new condition in connection with certain approximation properties of scaling functions enables to prove new relations among discrete scaling moments and consequently the same relations for continuous scaling moments.

Daubechies wavelets on intervals with application to BVPs

Václav Finěk — 2004

Applications of Mathematics

In this paper, Daubechies wavelets on intervals are investigated. An analytic technique for evaluating various types of integrals containing the scaling functions is proposed; they are compared with classical techniques. Finally, these results are applied to two-point boundary value problems.

Quadrature formulas based on the scaling function

Václav Finěk — 2005

Applications of Mathematics

The scaling function corresponding to the Daubechies wavelet with two vanishing moments is used to derive new quadrature formulas. This scaling function has the smallest support among all orthonormal scaling functions with the properties M 2 = M 1 2 and M 0 = 1 . So, in this sense, its choice is optimal. Numerical examples are given.

On the computation of scaling coefficients of Daubechies' wavelets

Dana ČernáVáclav Finěk — 2004

Open Mathematics

In the present paper, Daubechies' wavelets and the computation of their scaling coefficients are briefly reviewed. Then a new method of computation is proposed. This method is based on the work [7] concerning a new orthonormality condition and relations among scaling moments, respectively. For filter lengths up to 16, the arising system can be explicitly solved with algebraic methods like Gröbner bases. Its simple structure allows one to find quickly all possible solutions.

Approximate multiplication in adaptive wavelet methods

Dana ČernáVáclav Finěk — 2013

Open Mathematics

Cohen, Dahmen and DeVore designed in [Adaptive wavelet methods for elliptic operator equations: convergence rates, Math. Comp., 2001, 70(233), 27–75] and [Adaptive wavelet methods II¶beyond the elliptic case, Found. Comput. Math., 2002, 2(3), 203–245] a general concept for solving operator equations. Its essential steps are: transformation of the variational formulation into the well-conditioned infinite-dimensional l 2-problem, finding the convergent iteration process for the l 2-problem and finally...

On the exact values of coefficients of coiflets

Dana ČernáVáclav FiněkKarel Najzar — 2008

Open Mathematics

In 1989, R. Coifman suggested the design of orthonormal wavelet systems with vanishing moments for both scaling and wavelet functions. They were first constructed by I. Daubechies [15, 16], and she named them coiflets. In this paper, we propose a system of necessary conditions which is redundant free and simpler than the known system due to the elimination of some quadratic conditions, thus the construction of coiflets is simplified and enables us to find the exact values of the scaling coefficients...

Wavelet bases for the biharmonic problem

Bímová, DanielaČerná, DanaFiněk, Václav — 2013

Programs and Algorithms of Numerical Mathematics

In our contribution, we study different Riesz wavelet bases in Sobolev spaces based on cubic splines satisfying homogeneous Dirichlet boundary conditions of the second order. These bases are consequently applied to the numerical solution of the biharmonic problem and their quantitative properties are compared.

Quantitative properties of quadratic spline wavelet bases in higher dimensions

Černá, DanaFiněk, VáclavŠimůnková, Martina — 2015

Programs and Algorithms of Numerical Mathematics

To use wavelets efficiently to solve numerically partial differential equations in higher dimensions, it is necessary to have at one’s disposal suitable wavelet bases. Ideal wavelets should have short supports and vanishing moments, be smooth and known in closed form, and a corresponding wavelet basis should be well-conditioned. In our contribution, we compare condition numbers of different quadratic spline wavelet bases in dimensions d = 1, 2 and 3 on tensor product domains (0,1)^d.

A quadratic spline-wavelet basis on the interval

Černá, DanaFiněk, VáclavŠimůnková, Martina — 2013

Programs and Algorithms of Numerical Mathematics

In signal and image processing as well as in numerical solution of differential equations, wavelets with short support and with vanishing moments are important because they have good approximation properties and enable fast algorithms. A B-spline of order m is a spline function that has minimal support among all compactly supported refinable functions with respect to a given smoothness. And recently, B. Han and Z. Shen constructed Riesz wavelet bases of L 2 ( ) with m vanishing moments based on B-spline...

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