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101.
广义小波变换及其在人工神经网络中的应用 总被引:1,自引:0,他引:1
相应于非线性系统用人工神经网络的逼近问题,本文引入了一种新的小波变换并研究了其性质.作为推论,本文给出了在Lp范数下单个隐层前馈神经网络逼近定理的构造性证明. 相似文献
102.
Song Fu 《中国科学A辑(英文版)》1998,41(6):638-646
The theoretical foundation for the modelling of the turbulent pressure-strain correlations in rotating reference frame is
presented. Based on the recently developed materially-frame indifference principle it is observed that most of the existing
second-moment closures violate the Taylor-Proudman theorem in the limit of rapid rotation. It is shown that the application
of the materially-frame indifference principle gives rise to the formation of a new pressure-strain correlation model which
satisfies the Taylor-Proudman theorem.
Project supported by thr National Natural Science Foundation of China (Grant No. 19421003), the State Education Commission
and Tsinghua University. 相似文献
103.
A novel precision wavemeter is presented with a resolution of better than 0·01 nm. A Sagnac interferometer with two diffraction gratings forms the basis of the instrument. Using spatial heterodyning techniques and a CCD camera/frame grabber data acquisition system allows fast computer control and power spectrum analysis. The mode structure and mode hopping characteristics of a typical laser diode were examined as a function of diode injection current. 相似文献
104.
Karlheinz Gröchenig 《Advances in Computational Mathematics》2003,18(2-4):149-157
It is shown that every localized frame is a finite union of Riesz sequences. This is a partial solution to a question of Feichtinger. 相似文献
105.
106.
M. A. Oliver 《Foundations of Physics Letters》1991,4(4):337-350
The distribution of astronomical redshifts and the cosmic background radiation define a unique inertial reference frame. This paper contains an investigation of questions concerning quantum theory which arise with the introduction of a unique rest frame into spacetime. The Mössbauer effect, photon pair production, and photoelectric effect are treated together with photon scattering by a moving reflector and the Compton effect. Dirac's 1928 quantum theory of electrons is shown to yield its well-known energy spectrum for the hydrogen atom independently of the velocity of the atom relative to the rest frame.1. Address for the academic year 1990–91: 415 Graduate Studies Research Center, University of Georgia, Athens, Georgia 30602, USA. 相似文献
107.
To include the pointfree case, the notion of a Cauchy map easily extends as the condition that the preimage of any regular Cauchy filter contains a regular Cauchy filter. This extension, however, can be unsatisfactory if the regular Cauchy filters are scarce or non-existent, making the condition too weak, indeed sometimes even void. In this paper a variant of the notion, independent on the existence of any kind of filters, is studied: a homomorphism is called fully Cauchy if it lifts to the completions. This is generally stronger than, and in the spatial and metric cases it coincides with the previously mentioned property. Moreover, it is stable under localization. 相似文献
108.
本文给出了变质量非完整系统相对于非惯性系的第一积分存在的条件,建立了这类系统的正则方程和变分方程,证明了由第一积分可直接构造系统的积分不变量,并给出一系列推论和一个例子. 相似文献
109.
利用DirectDraw模块进行快速动画设计,重点对其直接操纵显存的特性和用后缓冲区实现动画中背景擦除和重绘的技巧进行探索,并结合火焰字的实例说明本文提出的方法是Win95下开发动画软件的一种切实可行的方法. 相似文献
110.
Bin Meng Maozheng Guo Xiaohong Cao 《Proceedings of the American Mathematical Society》2005,133(10):3087-3096
We introduce the operator-valued free Fisher information for a random variable in an operator-valued noncommutative probability space and point out its relations to the amalgamated freeness. Using M. Frank and D. Larson's modular frame notion we can construct the conjugate variable for an operator-valued semicircle variable with conditional expectation covariance. Then we obtain its free Fisher information and show it is equal to the index of the conditional expectation. At last the conjugate variable with respect to a modular frame operator for a semicircle variable is also constructed.