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101.
The theory of optical subdivision techniques of dual-frequency laser interferometers is stated. And a novel optical subdivision technique is proposed originally to enhance resolution of a commercial interferometer by adding some corner-cubes. Then the performance of the interferometer is tested. The interferometer resolution of 1.24 nm and the average error of below 2 nm are achieved by using the technique. The most novel of the optical subdivision technique is without λ/4 plates. It is less sensitive to environmental changes, it has prodigious potential to improve resolution farther and it can reduce polarization mixing error.  相似文献   
102.
Wavelets are generated from refinable functions by using multiresolution analysis. In this paper we investigate the smoothness properties of multivariate refinable functions in Sobolev spaces. We characterize the optimal smoothness of a multivariate refinable function in terms of the spectral radius of the corresponding transition operator restricted to a suitable finite dimensional invariant subspace. Several examples are provided to illustrate the general theory.

  相似文献   

103.
几何造型的有理矩阵细分方法   总被引:3,自引:0,他引:3  
Micchelli,Prautzsch给出了一类生成曲线的细分法-矩阵细分方程,但该方法仅能生成多项式类型的曲线,为了弥补其不足,本文提出了有理矩阵细分方法,并证明了其生成曲线的优良性质,例如凸包性,几何不变性,变差缩减性等。  相似文献   
104.
We prove the following recent conjecture of Halin. Let Γ0 be the class of all graphs, and for every ordinal μ > 0 let Γμ be the class of all graphs containing infinitely many disjoint connected graphs from Γλ, for every λ < μ. Then a graph lies in all these classes Γμ if and only if it contains a subdivision of the infinite binary tree. Published by John Wiley & Sons, Inc., 2000 J Graph Theory 35: 273–277, 2000  相似文献   
105.
In this paper,some characterizations on the convergence rate of both the homoge- neous and nonhomogeneous subdivision schemes in Sobolev space are studied and given.  相似文献   
106.
107.
研究多尺度多重向量值双正交小波的构建算法与性质.运用向量细分格式、矩阵理论和多重向量值多分辨分析,证明了与一对给定的多尺度多重向量值双正交尺度函数对应的多尺度多重向量值双正交小波函数的存在性.提出了紧支撑多尺度多重向量值双正交小波的构造算法.讨论了多尺度多重向量值小波包的性质,得到了多重向量值小波包的双正交公式与向量值小波包基.  相似文献   
108.
Abstract

This paper forms part of a study aimed at the development of a procedure for the determination of heavy metals in compost. The present paper deals with the sample preparation stage, including subdividing laboratory samples and reduction of the particle size.

The effect of particle size reduction on the random error due to the analysis of test portions was examined. It was found that milling for 20min in a quartz planet ball mill yields sufficiently homogeneous test samples. As the milling capacity of this device is too small, prior to milling subdivision of the laboratory sample is required. Subdivision before drying is recommended for practical reasons.  相似文献   
109.
The purpose of this paper is to investigate the mean size formula of wavelet packets (wavelet subdivision tree) on Heisenberg group. The formula is given in terms of the p-norm joint spectral radius. The vector refinement equations on Heisenberg group and the subdivision tree on the Heisenberg group are discussed. The mean size formula of wavelet packets can be used to describe the asymptotic behavior of norm of the subdivision tree.  相似文献   
110.
This paper presents a new numerical method for computing global stable manifolds and global stable sets of nonlinear discrete dynamical systems. For a given map f:ℝ d →ℝ d , the proposed method is capable of yielding large parts of stable manifolds and sets within a certain compact region M⊂ℝ d . The algorithm divides the region M in sets and uses an adaptive subdivision technique to approximate an outer covering of the manifolds. In contrast to similar approaches, the method requires neither the system’s inverse nor its Jacobian. Hence, it can also be applied to noninvertible and piecewise-smooth maps. The successful application of the method is illustrated by computation of one- and two-dimensional stable manifolds and global stable sets.  相似文献   
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