Multivariate filter banks with a polyphase matrix built by matrix factorization （lattice structure） were proposed to obtain orthonormal wavelet basis. On the basis of that, we propose a general method of constructing filter banks which ensure second and third accuracy of its corresponding scaling function. In the last part, examples with second and third accuracy are given.
The authors provide optimized local trigonometric bases with nonuniform partitions which efficiently compress trigonometric functions. Numerical examples demonstrate that in many cases the proposed bases provide better compression than the optimized bases with uniform partitions obtained by Matviyenko.
In the present paper, we discuss some properties of piecewise linear spectral sequences introduced by Liu and Xu. We have a study on the pointwise and almost everywhere convergence of its corresponding series. Also, it is shown that the set G constructed from piecewise linear spectral sequences are bases, but not unconditional bases, for LP（0, 1） where 1 〈 p 〈 ∞, p ≠2.
We propose a fully discrete fast Fourier-Galerkin method for solving an integral equation of the first kind with a logarithmic kernel on a smooth open arc,which is a reformulation of the Dirichlet problem of the Laplace equation in the plane.The optimal convergence order and quasi-linear complexity order of the proposed method are established.A precondition is introduced.Combining this method with an efficient numerical integration algorithm for computing the single-layer potential defined on an open arc,we obtain the solution of the Dirichlet problem on a smooth open arc in the plane.Numerical examples are presented to confirm the theoretical estimates and to demonstrate the efficiency and accuracy of the proposed method.
WANG Bo1,WANG Rui2 & XU YueSheng3,4,1Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190,China
