余弦波

Detection and analysis of power quality disturbances signal based on discrete cosine transform and wavelet transform.

基于离散余弦变换和小波变换的电能质量扰动信号检测方法。

Methods of Discrete Cosine Transformation and Discrete Wavelet Transformation are two ways, and also make a comparison of these two ways.

采用的方法是离散余弦变换和离散小波变换两种方法，并且还对这两种方法进行了比较。

For every ULA, the wide-band signals are sampled in spatial and temporal, then 2-D discrete Fourier transform is carried out. A projection operation on 2-D representation of wide-band signals is applied in the spatial-temporal frequency domain. The direction cosine relative to the ULA axes is estimated by MUSIC algorithm.

该方法采用3个共面的均匀线阵，每一均匀线阵对宽带信号空间采样，然后进行空时二维DFT变换，在空时频率域对宽带信号进行投影变换，用MUSIC算法实现宽带来波信号方向余弦的估计。

At present,the research of digital watermarking focused on discrete fourier transform domain, Discrete cosine transform domain, Discrete wavelet transform domain and others, but its robustness need to be improved.

目前，对于频域数字水印技术的研究主要集中于离散傅里叶变换域、离散余弦变换域和离散小波变换域等，但其鲁棒性能都有待提高。

Adaptive filtering ; time-domain LMS ; discrete Fourier transform ; discrete cosine transform ; discrete wavelet transform

自适应滤波；时域LMS ；离散Fourier变换；离散余弦变换；小波变换

Then, the concept of frequency warping is then extended to discrete Fourier transform, discrete cosine transform and discrete wavelet transform, i.e., applying the idea of nonuniform frequency resolution to these common transforms.

接著，我们将频率变形的概念延伸离散傅立叶转换、离散余弦转换以及离散小波转换，把不均匀频率解析度的原理应用在这些讯号处理常使用的转换式上。

It is shown that many of the existing integral transforms (including their logically equivalents) such as chirplet transform, dispersion transform, wavelet transform, chirp-Fourier transform, short-time Fourier transform, Gabor transform, Fourier transform, cosine transform, sine transform, Hartley transform, Laplace transform, z transform, Mellin transform, Hilbert transform, autocorrelation function, cross-correlation function, and the energy and mean of a signal, can each be considered as a special case of the FMmlet transform with specific parameters. In fact, an inventory of subspaces of FMmlet transform runs into countless numbers. The subspaces mentioned above are merely a few among a zoo of subspaces. They are essentially obtained by cutting the transform space of FMmlet transform at different positions, and can be likened to the computed tomography in medical diagnosis. Through these subspaces we actually see different slices or profiles of the FMmlet transform.

将现有诸多变换置于统一的 FMmlet 变换中加以审视，发现 chirplet 变换、频散变换、小波变换、 chirp-Fourier 变换、短时 Fourier 变换、 Gabor 变换、 Fourier 变换、余弦变换、正弦变换、 Hartley 变换、 Laplace 变换、变换、 Mellin 变换、 Hilbert 变换、自相关函数、互相关函数、能量和均值等，均为 FMmlet 变换在其参数取特定值时的特例；上述诸变换之间的差别，主要在于变换空间的维数有别，以及在不同空间维上取值的不同；这些变换有如医学诊断中的 CT，均由压缩 FMmlet 变换域空间所致，可以说我们通过这些变换看到的，是 FMmlet 变换的不同剖面。

Contents : Chapter 4 Image Enhancement (contrast enhancement, gray transform, histogram dressing, image smoothing, sharpening, Pseudo-color and false color enhancement); Chapter 5 of Image Restoration (inverse filter rehabilitation, Wiener filtering method); Chapter 6 of image processing orthogonal transformation Fourier transform, discrete cosine transform (DCT, the Walsh transform, Based on the eigenvectors of transformation, Hotelling transform, SVD transform, wavelet transform, Mallat algorithm; Chapter 7 Image Coding Hoffman (Huffman coding, arithmetic coding, RIc, the bit-plane coding, predictive coding, DPCM.

内容：第4章图像增强（对比度增强、灰度变换法、直方图修整法、图像平滑、图像锐化、伪彩色和假彩色增强）；第5章图像复原（逆滤波复原、维纳滤波方法）；第6章图像处理中的正交变换（傅立叶变换、离散余弦变换、沃尔什变换、基于特征向量的变换、霍特林变换、SVD变换、小波变换、Mallat算法）；第7章图像压缩编码（霍夫曼编码、算术编码、游程编码、位平面编码、预测编码、DPCM、JPEG 2000编码

A novel true 2-D nonseparable wavelet filter bank-all phase discrete inverse cosine sequency filter was presented.

构造了一组新的纯二维不可分离的小波滤波器―全相位离散反余弦列率滤波器。

According to Floquet theory and transition curves of Mathieu equation, two different modified strained parameter methods are compared on precision of periodic solutions.

中文摘要：为研究参数横摇对船舶运动和倾覆的影响，通过对船在规则波上随浪航行时，恢复力矩中出现的1个以正余弦规律变化的强参数激励项进行适当的变量置换，将船舶的横摇运动方程转换成标准形式的Mathieu方程。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。