查询词典 wavelet

At this text I bring forward effective project strategy of non-maturity haleness watermark model arithmetic. Making use of time-frequency local characteristic of wavelet switch, I bring forward digital image watermark insetting project basing on block of wavelet switch, at the first ,make the image disporting to block of 8×8,then make use of the characteristic of Haar wavelet switch,then make the image the second layer wavelet switch and carry through power modulus transaction.

本文提出了非完备性鲁棒性数字水印典型算法中的行之有效的设计策略，利用小波变换良好的时频局部特性，提出了基于块的小波变换的数字图像水印嵌入方案，把宿主图像分为8×8的小块，利用 Haar小波变换的特性，对图像进行二层小波变换分解，对变换系数进行权重处理，然后把每一个水印象素隐藏在相应的图像块的中低频小波系数之中，提高了数字水印的隐蔽性和鲁棒性。

The definition of Wavelet Analysis is that shifting the mother wavelet e.g. which has limited energy, such as shifting for, then proceeding dimensions, we obtained wavelet basis function ,, which make the inside product to the function to analysis With the Fourier transformation to the and, then the equivalent frequency spectrum of wavelet transformation can be expressed as where 、 are the transformations of 、 respectively and i is an imaginary number unit.

小波变换的含义是：把一具有有限能量的母小波，如进行移位后，再进行尺度的伸缩得到小波基函数为然后与待分析的函数作内积，即对和作Fourier变换后，可得到小波变换的等效频域表示为：其中、分别是、的Fourier变换，i为虚数单位。

This paper describes a wavelet filter using wavelet transform method,it obtains the rational formula of wavelet function around the mathematical approximation of a mother wavelet. By using Mexican Hat wavlet as an example to simulate the approximation process and using Matlab to simulate.

本文描述了一种用小波滤波器实现小波变换的方法，它通过对母小波的一种数值逼近得到小波函数的有理公式，并以Mexican Hat小波为例来模拟这个逼近过程并用Matlab对逼近过程进行仿真。

The choice of the best wavelet bases is one of the subjects attracting more attentions. This paper presents a new choosing method based on numerical analysis. Here the coding performance of wavelet bases is evaluated overall numerically by using several standards, which had been confirmed to be relating to image coding The best chosen wavelet bases fitting static images and video coding are respectively Daubechies's biorthogonal wavelet 9-7 and 5-3, which have been proved by coding experiments.

最佳小波基的选择是倍受关注的问题之一，本文提出一种新的基于数值分析的挑选方法，通过用几个已被证实是与图像编码密切相关的小波基评价标准对小波基的编码性能进行全面的数值评价，并经实际编码检验，选出了适宜静态与活动图像编码的最佳基分别为Daubechies双正交小波9-7与5-3。

The practical employment of multidimensional wavelet is only limited to tensor product wavelet. To construct a tensor product orthonormal wavelet basis in L〓, 2〓-1 different mother wavelets are used, and thus storing and computing wavelet basis of large dimension are of prohibitive cost.

根据Meyer的小波基存在性定理，利用张量积方法构造L〓的一个规范正交小波基，需要2〓-1个不同的函数，存储和计算方面的开销太大，在实时应用方面尚有很大的局限性。

Tansformed the real part and imaginary part of interferogram to stationary wavelet domain, analyzed the PDF of signal and noise wavelet coefficients using Pearson distribution system, then evaluated the wavelet coefficients of signal in stationary wavelet domain by Maximum A Posterior criteria to reconstruct the interferogram.

2将干涉图的实部和虚部分解到静态小波域，用Pearson分布系作近似，分析了信号和噪声小波系数的概率密度函数，在静态小波域用MAP准则估计信号的小波系数用于干涉图的重建。

The results of quantitative coding to wavelet transform coefficient show that low-scale extreme wavelet coefficients can accurately localize the subaerial position of fractures.The shifting of extreme wavelet coefficients can be used to judge relative magnitude of dip angle and dip direction of fracture with scale increasing.The value of extreme wavelet coefficients can reflect density difference of formations on both sides of fracture and provide information of physical properties for fracture analysis.

小波变换系数量化编码结果表明，低尺度小波系数极值可以准确定位断裂在地表的位置；随着尺度的增加，小波系数极值会发生偏移，可以判断断裂的倾向和倾角的相对大小；小波系数极值可以反映断裂两侧地层的密度差异，为断裂分析提供物性信息。

A new approach for pattern recognition of ultra-high frequency signals of transformer partial discharge based on multi-scale analysis of wavelet packet and grid dimensionality is proposed, in which the multi-scale transform of wavelet packet is used to extract wavelet coefficients of UHF PD signals and by means of improving difference box-counting method the grid dimensionality of multi-scale wavelet coefficients is calculated and the multi-scale grid dimensionality is taken as the characteristic quantity that is used in the recognition of UHF PD signals.

提出了一种基于小波包多尺度分析和网格维数的变压器局部放电超高频信号模式识别的新方法，采用小波包多尺度变换提取局部放电超高频信号在多尺度上的小波系数，通过改进差盒计数法计算多尺度小波系数的网格维数，并将多尺度网格维数作为特征量用于局部放电超高频信号的识别。

The common methods of wavelet transform incudes the best wavelet packet-based method, embedded wavelet prediction coding ,wavelet zero-tree compression factor, and so on.

常见的基于小波变换的图像压缩方法有小波包最好基、嵌入式小波预测编码和小波系数零树压缩等。

The issues of present seismic wavelet frequency caused by different concepts, such as apparent frequency, dominant frequency, peak frequency and centroid frequency, etc., which are defined by different methods, and understanding deviation, definition of seismic wavelet frequency for time and frequency domain are concluded and summarized. On this basis, three kinds of seismic wavelets in common use such as Ricker and Zinc wavelets as well as sine wavelet with exponential attenuation characteristics are analyzed and a conclude is achieved that apparent frequency and dominant frequency are consistent in essence, but peak frequency and centroid frequency as well as apparent frequency or dominant frequency are not completely consistent with different seismic wavelets. For actual seismic data, peak frequency can approximately be used as dominant frequency, but it is not suitable when seismic wavelet is known for it can give out any wrong knowledge and results.

针对目前地震子波频率由于定义方式出现的各种概念（视频率、主频、峰值频率、中心频率等）以及理解上出现的偏差等问题，首先从时间域定义和频率域定义2个方面进行了归纳和总结，并在此基础上对3种常用地震子波（Ricker子波，Zinc子波，正弦指数衰减子波）进行了分析和研究，得出视频率与主频概念一致，但不同地震子波的峰值频率、中心频率和视频率之间并不完全一致的结论；而对于实际地震资料，将峰值频率近似看作地震子波的主频是可以的，但在地震子波已知的情形下这样做是不恰当的，甚至可能会得出错误的结论和认识。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。