Scientists and technologists of many countries have dedicated a great effort to solve this problem , many achievements were achieved , a lot of measures to decrease vibration and noise were made out . each kind of measure has certain effect to decrease vibration and noise 各国科技工作者已经对此展开了长期深入的研究,取得了很多的成果,并制定了一些减振降噪的措施,每一种措施都有一定的减振降噪效果。
Study mechanical vibration and noise theory , through analyzing the frequency spectrum of the vibration noise , study the spread characteristic of the vibration noise and method and technology of reducing vibration and noise , improve the security and environmental protection of the equipment operation 研究机械振动与噪声理论，通过对振动噪声的频谱分析，研究振动噪声的传播特性及减振、降噪的方法与技术，提高设备运行的安全性和环保性。
( 2 ) a new perturbation method for noise reduction of chaotic signal is promoted , the approach consists of deploying a series of proper disturbance to the observing orbit yn = ( yi , y2 , . - . j / / ) ? so as to gradually acquire the estimation xn - ( jc , , 5c2 , . . . , jcw ) of the real orbit xn = ( * i , x2 , . . . , xar ) P ）提出了一种混饨信号降噪的微扰方法，其基本思想是通过在观测轨道yn blot ， …砌上施加一系列适当的微扰来逐步得到真实轨道xn （ x ? ， …砌的估计值及。
After analyzed the basic principle of optimized noise reduction on tyre pattern , summarized three approaches to noise reduction . the first is trying to reduce size of single block or socket to reduce noise amplitude on time domain , the second is to adjust stripes sorting order and their interlace value to avoid noise - made by every single block - peak values on time domain overlayed and the last is to adjust ratio of blocks and sockets , ratio of stripe interval and stripe sorting order to avoid noise periodical distribution and abnormal high peak values in some frequency strip 论文第四章分析了轮胎花纹优化降噪的基本原理，总结出三条降噪途径：在允许范围内尽量减小单个块或槽的大小、刻刀槽软化花纹块来减小噪声时域波幅度；调整节距排列顺序、花纹条之间的错位值，使各发声单元发出的声压时域波形的同向峰值错开，避免同向峰值叠加；调整花纹块和槽比例、节距比例、节距排列顺序，尽量避免周期性分布，使轮胎所发出的噪声趋于白噪化，避免某些频段的异常高峰值。
In the de - noise part , the author firstly proved that the snr of the live image can be improved by integrating several images . because the subtraction images are image sequences , which related to time , so in the arithmetic realization , different images are integrated after assigning different weight that is convenient for optimization 在降噪的处理过程中首先从理论分析中证明了通过积分累加可以使得造影图象的信噪比获得提高，在实现中考虑到数字剪影图象是与时间有关的序列，因此采用利于优化的多权重积分累加，提高了运算效率。
Through using for reference and demonstrating the technology of video processing system of domestic and foreign , author has put forward a set of video processing system schemes suitable for the china " s actual conditions . by using the digital technology , such as digital encode - decode , digital phase - locked , digital filter , digital image storing , the system schemes realizes tv signal noise reduction and time error elimination in real time , and makes the system be a integrated noise reduction and time based corrector really 通过借鉴和论证国内外时基校正和视频降噪的相关技术，作者提出了一套适合于中国国情的视频处理系统软、硬件方案实现模拟电视的信号数字转换以及利用数字编解码、数字锁相、数字滤波、数字图像存储等数字技术来实现电视信号实时去噪和消除时基误差，使系统真正做到集时基校正与降噪一体化。
Specifically , this thesis includes the following work : the basic theory of speech processing and noise in speech reduce . we study the short interval character of speech signal and short interval process technology , and classify the noise and disturbance in wireless receiver terminal into 3 categories and present corresponding schemes 本文针对高质量无线语音传输的需求,对语音处理及语音降噪的基础理论、关键技术及降噪设备的实现方法展开研究,在此基础上设计实现了无线语音通信降噪器实验系统,并对实验系统的降噪效果进行了测试。
The dynamic predigesting model for passive isolation of flexible base system was established , and the four - pole parameters and machinery impedance methods were adopted to analyse the system , the expression of the responsibility and power flow transmissibility was deduced . by means of the matlab programming language , the responsibility and power flow transmissibility were simulated . proposed the vibration contrl method of optimizing system parameters . the methods proposed in this dissertation , can meet the requirement of decreasing vibration and noise for flexible base , and have some practicability and reference value 对柔性基础被动隔振系统进行了力学建模简化，并采用四端参数和机械阻抗方法对其进行分析，推导出其响应比和功率流传递率的表达式，并利用matlab程序设计语言对响应比和功率流传递率进行了模拟仿真。提出了以优化系统参数为措施的振动控制方法。本文所提出的方法，能够满足柔性基础减振降噪的要求，具有一定的实用性和参考价值。
The applicability of several commonly used de - noising methods is examined in signal analysis of instant vibration testing for soil compactness . the analysis result indicates that the method based on wavelet thresholds is the best . the method for determination the threshold of wavelet de - noising is also proposed to satisfy soil compactness test signal 对比了几种常用信号降噪方法在土密实度瞬态振动测试信号中的适用性，得到了小波阈值降噪法最适用于土密实度瞬态锤击测试信号的结论，并给出了适用于土密实度测试信号降噪的小滤阈值确定方法。
This dissertation aims at the problem of the noise of over length truck falling short of the lately country standard , and makes research on the reason of the gear - box vibrating noise . by combine using finite element analysis and experimental analysis method , the dissertation directly researches the vibrating noise of the gear - box , and takes some availability measures to control vibrating noise from the box surface . by improving the box to reduce its noise , and validate the effect 本文针对一汽超长载重汽车噪声指标不符合国家最新标准的实际问题,对其变速箱振动噪声的产生机理进行深入研究,应用有限元分析与实验分析相结合的方法直接对其进行振动和噪声分析,在此基础上提出控制其振动噪声的有效措施,并通过对其箱体的改进设计,最终达到减振降噪的目的。
