信噪比

The simulation results show that the denoising effects of the three methods are all superior to that o f Fourier transform, and the influence of colored noise can be eliminated effectively by bispectrum methods. That is very i mportant for reconstructing LoranˉC signal under the condition of small signalˉtoˉnoise ratio, and also lays the fou ndation for digital LoranˉC signal processing.

仿真分析结果表明，三种方法的去噪效果都优于传统的傅氏变换法，且双谱估计能够有效地去除色噪声的影响，对于小信噪比条件下的罗兰C信号的提取和恢复具有重要意义，也为复杂环境下对罗兰C信号的数字处理奠定了良好的基础。

In order to improve the signal-to-noise ratio of the pulsar signal, a wavelet denoising algorithm based on fuzzy threshold is put forward.

为了提高脉冲星辐射脉冲信号的信噪比，提出了基于模糊阈值的小波降噪算法。

It is necessary to study image denoising methods to enhance image signal to noise ration.

为了提高图像的信噪比，对图像降噪方法的研究是十分必要的。

In functional optical imaging,the very low SNR makes the sample covariance matrix have singularity,which brings the whitening the operation of the ICA denoising method to reduce the dimensionality,so the ICA denoising method will lost the signal detection ability.

在光学功能成像中，极低信噪比会使得样本协方差矩阵具有奇异性，因此导致Emir等人提出的ICA去噪方法在白化预处理过程会出现降维现象，最终使得该方法无法检测出信号。

The experiments show that the proposed image compression and denoising method can significantly outperform those that are based on Bandelet or Contourlet transform in visual quality for the images with abundant edges and texture, and the peak signal to noise ratio is also increased by more than 0.1 dB.

实验结果表明，对于纹理和边缘丰富的图像，所提出的图像压缩和去噪方法在视觉质量上明显优于基于Bandelet或Contourlet变换的方法，峰值信噪比也提高了0.1dB以上。

The eminent performance of this method is proved by its higher SNR(signal- to- noise rate), smaller MSE(Minimizes the mean squared error) The discal surface of the contaminated insulators is the interesting area of the research.

数值试验证明，与固定阈值法和极大极小阈值法比较，运用该方法去噪后的图像具有更高的信噪比和更小的最小均方误差。

In this work,a signal process method for NQR signals is presented,which is based on wavelet transform and specially designed for the detection of pentaerythritol tetranitrate with NQR.

为提升NQR信号信噪比，根据NQR信号的特点，提出了一种基于改进阈值函数小波变换的NQR信号去噪方法。

By ultrasonic echo noise-reduction testing on CS-1-5 test block's flat bottom hole and certain helicopter totors' fatigue flaw, it is shown that ultrasonic signal SNR is increased remarkably.

经对CS-1-5试块的Φ2平底孔超声反射回波和某型直升机旋翼大梁疲劳裂纹超声反射回波的降噪试验，试验结果表明，处理后的超声信号信噪比显著增强。

For frequency information fluid identification technology:the basic theory of fluid identification based on frequency information has been introduced,for inner and external factor affecting frequency,some steps have been proposed to attain reserved amplitude and frequency analysis data with high resolution,high S/N ratio;through the comparison of time-frequency analysis method, the high accuracy time-frequency analysis method has been selected to extract time-frequency attributes;the analysis method flow of common single frequency fluid identification has been proposed,according to the data of full frequency band,several anomaly zone modes of common single frequency attribute have segregated; incorporating converted wave and compression wave,fluid identification method based on PS wave combined time-frequency analysis has been proposed;the AVO property of various fluid type in frequency domain has been studied;the generalized fourier analysis method,Proni absorption filter has been introduced,and researched for anti-noise and for the seismic processing interpretation flow.The above technology have been applied to fluid identification of organic reef in WBT area in the east of Sichuan and fluid identification of clastic rock in GUANGAN area in the middle of Sichuan,the results show that the above methods are effective.

基于频率信息的流体识别技术方面：介绍了利用频率信息流体识别的基本理论，针对影响频率的内、外在因素，提出一些针对措施，以获得高分辨率、高信噪比的保幅、保频分析数据；通过时频分析方法的比较，选取高精度的时频分析方法提取时频属性；提出共单频属性进行流体识别的分析方法流程，结合全频带数据，分出几种共单频属性异常带模式；联合转换波资料和纵波资料，提出基于纵横波联合时频分析进行流体识别方法；研究了频率域内不同流体类型AVO现象；引进一种广义傅立叶分析方法：Proni吸收滤波，研究其抗噪性以及进行地震处理解释的流程；将这些技术应用川东北五百梯区块进行生物礁储层流体的识别和川中广安陆相碎屑岩的流体识别，取得较好的效果。

Two image quality evaluation of the function. Including psnr PSNR, it is mean-square error nmse other. Images can be used for de-noising and compression of image quality evaluation.

详细说明：两个图像质量评价函数，psnr峰值信噪比，正则均方误差nmse，能可用于去噪图像和压缩图像的质量评价，很有用啊。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。