传统的特征提取方法主要有：主分量分析、奇异值分解、投影追踪、自组织映射等。

Classical feature extraction methods include: Principle Component Analysis, Singular Value Decomposition, Projection Pursuit, Self-Organizing Map, and so on.

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利用混沌映射结合矩阵奇异分解，将水印信息分散在原始图像的不同位置，提高了水印的视觉效果，保证了水印的安全性。

Chaos map and singular value decomposition of matrix technology are introduced to improve the watermarking imperceptibility, security and robustness of watermark image.

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冲击振动系统的映射“擦边”奇异性可能是这种非常规转迁过程的主要原因。

Grazing dis continuities in the poincare map of the vibratory system with a gap are likely to be a major cause of the unusual routes to chaos for the system.

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