噪声抑制

However, for the nonperiodic signal buried in high power noise, conventional method are usually not so effective as in the case with lower power noise.

然而，对于淹没于高功率噪声中的非振荡信号，传统的抑制噪声方法是无效的。

The main works are as follows:Firstly, in order to produce quincunx down sampling and up sampling which could form directional wavelet transform, the rotated factor matrixes is introduced based on discrete wavelet transform.

在遥感图像去除噪声的过程中提出一种软阈值映射函数，在不同尺度的高频子带图像采用不同的软阈值增益，并采用新的阈值估计算法来确定不同分辨率的高频小波系数的分布来进行图像噪声的有效抑制。

Aimed at the use of underwater active detection system, an analog pretreatment circuit is designed. More than one amplifier and two filters are used to process the signal. The signal can be amplified and self-excitation is avoided. The series of AD867X are used to restrain the circuit noise.

针对水下主动探测系统的应用，设计了一种模拟预处理机，该电路采用分级放大结构，并使用两级滤波器对信号进行滤波处理，在达到对信号放大倍数要求的同时避免了放大器自激，采用噪声性能好的AD867X系列芯片有效抑制了电路噪声对信号的影响。

For the singular spectrum analysis of time series, a method of constructing covariance matrix by using forth order cumulant is proposed. The method could restrain the Gaossian noise and symmetrical distributed noise mixed with chaotic signals.

对于时间序列的高阶奇异谱分析，提出了一种利用四阶累积量函数构造协方差矩阵的方法，该方法从理论上能有效地抑制叠加在混沌信号中的高斯噪声和对称分布噪声对重构结果的影响。

In order to provide a photo detector in which the generation of spontaneous noise is suppressed and external noise is effectively reduced, a p-type diffusion layer is provided on the obverse side of an n-type semiconductor substrate, a p-type low-resistance layer is provided on the obverse side of the p-type diffusion layer, a lead frame is provided on the reverse side of the n-type semiconductor substrate with an insulative resin film in between, and the p-type low-resistance layer is electrically connected to the lead frame.

为了提供能够抑制自发噪声的产生并有效地减少外部噪声的光检测器，在n型半导体衬底正面设置p型扩散层，在p型扩散层正面设置p型低电阻层，在n型半导体衬底的反面设置引线框架、中间夹有绝缘树脂薄膜，p型低电阻层电连接到引线框架。

This paper deals with the key technique of the portable vibrator system,whose correlation and tapper processing can restrain random noise and improve resolution greatly.

笔者介绍了轻便可控震源的关键技术，相关与锥化能有效地抑制随机噪声及环境噪声，提高信噪比与分辨率。

The numerical results show that the filter is suitable for the reduction of both Gaussian noise and noise with uniform distribution.

大量的实验结果表明，该滤波算法对Gauss白噪声及均匀分布的噪声都有良好的抑制特性。

To meet the needs, a novel low-noise fiber laser with compound cavity structure is designed. The stable single-mode operation is realized by using a transient self-written fiber grating, produced by the effect of saturable absorption within a section of unpumped erbium-doped fiber, as narrow band filter for mode selecting and linewidth squeezing. Through optical path modification, the spectral signal-to-noise ratio is better than 62 dB.

激光器采用复合腔结构，以掺铒光纤作为工作物质，通过在未被抽运的掺铒光纤中形成的瞬态自写入光纤光栅的窄带滤波特性进行选模和压窄线宽，产生稳定的单频激光输出；经过光路改进，激光输出光谱信噪比优于62 dB；利用光电负反馈电路，弛豫振荡峰下降了约25 dB，低频段强度噪声也大为改善，有效地抑制了光源的强度噪声。

This study has achieved the following purposes,observed effects of different levels of noise exposure on the auditory function and the hearing organ of guinea pigs,explored optimal noise exposure profiles for research of NIHL susceptibility,established NIHL susceptibility model,148 differentially expressed genes of cochlea between NIHL susceptible and unsusceptible guinea pigs were screened by using suppression subtractive hybridization.The results of bioinformatics analysis showed that there are 34 sequences whose homology were larger than 80% and match sequence larger than 100 bp.

本研究观察了不同噪声暴露量对豚鼠听觉功能和听觉器官结构的影响，探讨了NIHL易感性研究的最佳噪声暴露方案，建立了NIHL易感豚鼠模型，利用抑制性消减杂交技术筛选NIHL易感与不易感豚鼠耳蜗的差异表达基因片段148条，生物信息学结果显示同源性大于80%且匹配碱基大于100 bp的片段共34条。

In order to enhance the image with better anti-noise ability,this paper proposes a image pre-processing algorithm based on lateral inhibition and adaptive filter,which can not only outstands the image'outline,but also eliminates the noise by adaptively changing the model parameters accordingly to the local image's mean,variance and the noise variance.

为了既能增强图像，又具有较好抗噪性能，提出一种基于侧抑制网络和自适应滤波相结合的图像预处理算法，不仅突出了图像的轮廓，而且能根据图像的局部均值和方差以及噪声方差的不同，自适应地改变模型的参数来消除噪声。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。