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一种基于ICA的盲信号分离快速算法 总被引：11，自引：0，他引：11
基于ICA(独立成分分析:Independent Component Analylsis)原则,给出一种盲信号分离的快速学习算法.通过寻求观测变量线性组合的四阶累积量(即kurtosis系数)局部极值,得出该算法的模型和步骤.将该算法用于盲信号分离实验,实验结果表明,该算法在盲信号分离和信号特征提取方面具有收敛速度快、无需动态参数等优点.该算法能有效地分离出任意分布的非高斯盲源信号的各个独立成分,是信号处理的一种新的、高效可靠的方法. 相似文献
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根据CO分子吸附在Pt表面相互作用的类Rose势中的不同吸附能参量E0、振动参量α0和平衡间距γe,利用时域有限差分方法数值求解CO-Pt吸附体系的Schr(o)dinger方程,得到CO-Pt体系波函数的数值解.通过离散Fourier变换得到本征振动能量,并拟合成非谐性光谱项表达式.结果表明E0对CO-Pt体系的振动频率影响不大,而α0变小或γe变大时体系振动频率降低,导致谱线红移;同时表明CO-Pt体系的本征振动仍接近谐振动. 相似文献
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利用复数坐标系上的保角变换和利用势的拉普拉斯方程分别讨论了带有半圆柱形凸出疤和半球形占出疤两种有缺陷的平行板电容器的电场分布,进而得出一些有益的结论。 相似文献
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In view of the disadvantages of the traditional phase space reconstruction method,this paper presents the method of phase space reconstruction based on the wavelet decomposition and indicates that the wavelet decomposition of chaotic dynamical system is essentially a projection of chaotic attractor on the axes of space opened by the wavelet filter vectors,which corresponds to the time-delayed embedding method of phase space reconstruction proposed by Packard and Takens.The experimental results show that,the structure of dynamical trajectory of chaotic system on the wavelet space is much similar to the original system,and the nonlinear invariants such as correlation dimension,Lyapunov exponent and Kolmogorov entropy are still reserved.It demonstrates that wavelet decomposition is effective for characterizing chaotic dynamical system. 相似文献
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Based on the nanostructured surface model that the (platinum,Pt) nanocones grow out symmetrically from a plane substrate, thelocal electric field near the conical nanoparticle surface iscomputed and discussed. On the basis of these results, the adsorbedCO molecules are modelled as dipoles, and three kinds ofinteractions, i.e. interactions between dipoles and local electricfield, between dipoles and dipoles, as well as between dipoles andnanostructured substrate, are taken into account. Thespatial configuration of CO molecules adsorbed on the nanoconesurface is then given by Monte-Carlo simulation. Our results show thatthe CO molecules adsorbed on the nanocone surface cause localagglomeration under the action of an external electric field, andthis agglomeration becomes more compact with decreasing conicalangle, which results in a stronger interaction among molecules.These results serve as a basis for explaining abnormal phenomenasuch as the abnormal infrared effect (AIRE), which was found when COmolecules were adsorbed on the nanostructured transition-metalsurface. 相似文献
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Combination of the wavelet transform and independent component analysis （ICA） was employed for blind source separation （BSS） of multichannel electroencephalogram （EEG）. After denoising the original signals by discrete wavelet transform, high frequency components of some noises and artifacts were removed from the original signals. The denoised signals were reconstructed again for the purpose of ICA, such that the drawback that ICA cannot distinguish noises from source signals can be overcome effectively. The practical processing results showed that this method is an effective way to BSS of multichannel EEG. The method is actually a combination of wavelet transform with adaptive neural network, so it is also useful for BBS of other complex signals. 相似文献
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过渡金属纳米结构表面吸附CO分子时会出现异常红外效应,这一现象可以用纳米结构表面吸附分子在外电场作用下产生局部凝聚从而相互作用能增加来解释.在前期研究的基础上,给出金属基底表面生长出的纳米颗粒为椭球状颗粒的理论计算结果.基于均匀外电场中金属纳米椭球颗粒按一定对称性排列的表面结构模型,用经典电磁学理论计算了纳米椭球颗粒表面附近的局域电场.在此基础上,将吸附的CO分子等效为偶极子,在考虑了偶极子与局域电场、偶极子之间以及偶极子与金属基底三种相互作用的情况下,用Monte-Carlo方法进行数值模拟,最后给出纳关键词：金属纳米结构表面纳米椭球吸附分子局域电场 相似文献
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基于Maxwell—Garnett(M-G)有效介质理论,建立 了研究金属纳米不连续薄膜光学性质的理论 模型,对半球形纳米颗粒在等效薄膜中的体积分数和纳米尺度效应提出修正处理; 给出了可见光区附近Au纳米颗粒等效薄膜的有效相对电容率和光学常数随波长变化的结果, 并 获得薄膜的光反射率、透射率和吸收率随膜纳米尺度的变化谱。计算结果表明,金属纳米等 效 薄膜有效电容率和光学常数随纳米尺度增大而增大,谱峰出现很小的红移。进一步发现,纳 米尺 度越小,光的反射率和吸收率越小,但透射率越大,峰值位置随纳米尺度增大有小量红移, 结果与实验相符。 相似文献