查询词典 noise elimination

Based on the noise theory and experi mentation ,the author founded the onli ne method to test current noise , validated the relation bet ween te mperature ,aperture and pressure with current noise .This paper firstly analyzed gener— ati ng mechanis mof discharge niose ,studied the measure and factor of discharge niose ,i ndicated an effective method for degradi ng the discharge noise ,which pro moted the performance of laser gyro fro m0.01°／h to 0.001°／h.

文中以氦氖气体激光器的噪声特性理论为指导，以试验研究为基础，建立了在线噪声电流测试方法，通过试验验证了温度、腔体毛细孔径、谐振腔充气气压等参数与放电噪声的关系，首次提出了放电噪声产生的机理，分析了电流噪声的检测方法及影响因素，给出了减小和抑制放电噪声的有效方法，使得激光陀螺的性能由0.01°／h 提高到0.001°／h。

At present, the city has chosen the 30 kinds of green plants mainly noise, absorption and scattering properties of the test, found the crown of large, heavy branches of trees, such as cypress, camphora, Ligustrum, Photinia, coral and so on, by Noise excellent skills; oleander, octagonal gold, small wax, shrubs and other mosquito-mother, but also the noise of the reactive barrier, which will provide noise reduction mature green residential experience.

目前，该市已选择了30种主要绿化植物噪音，吸收和散射特性的测试，发现树冠大，重型分行的树木，如柏树，香樟，女贞，石楠，珊瑚等，噪声优秀技能；夹竹桃，八角金，小蜡，灌木及其他经蚊子母亲，而且噪音屏障的反应，这将提供降噪成熟绿色住宅的经验。

Preprocessing consists of data selection, baseline adjustment, noise filtering and peak identification. Data selection removes preprimer data section which contains little useful information. Baseline adjustment adjusts the baselines of four channels to the same level. Noise filtering removes the impulse noise and white noise. Peak identification selects the peak data for use in cross matrix determination.

预处理包括数据段选取、基线调整、噪声滤除、峰值识别四个模块：数据段选取删除前段冗余数据；基线调整使得四色荧光信号的基线高度一致；噪声滤除去除信号中的脉冲噪声和白噪声；峰值识别选取峰值数据，作为求解串扰矩阵的数据。

Based on summarying the measures of traffic noise control in the world, in terms of theory and experience of noise control , as well as adapting concrete environmental condition and development tendency china western , this paper puts forward the measures of traffic noise control which reduct the effect of noise pollution and accelerat the management of highway environment protection .

在总结国内外防治交通噪声措施的基础上，根据噪声控制的理论经验，结合西部地区具体环境状况和发展趋势，提出了适合中国西部的交通噪声防治对策，以减少噪声污染和推动西部地区交通环保事业的发展。

This essay will remark on auto air-condition noise problems through studying expansion valve. The main reasons incurred noise are two, one is vibration, which is from big air bubble caused by the refrigerant flows through expansion valve. Another is resonance, which is from engineering working itself. So, the two methods for eliminating noise are found. On one hand, through increasing damp to weaken resonance. On another hand, through taking off air bubble to eliminate vibration. The essay presents method of solving noise through improving expansion valve and elaborate the disadvantages caused by these solvement.

本文从膨胀阀的角度去考虑解决汽车空调异响问题，认为产生异响的主要原因是制冷剂流经膨胀阀节流部时有大气泡存在引起振动与汽车发动机共振造成，从增加阻尼块来减振和分解大气泡来消除震动等两方面提出解决方法，并对此方法造成的不利方面也进行了阐述。

With the support of a major research grant of Zhejiang Province (No. 001101027) and the Plan of Promoting Education of Excellence of Zhejiang University in the 21st Century, this dissertation is devoted to address the above problems and fabricate an L-band EDFA with low cost, high performance and technological innovation.First the mechanism of an erbium doped fiber amplifier is introduced. Various theoretical models based on classical rate propagation equations are summarized and compared for their applications. We use a modified numerical model based on the Giles model, which agrees with the experimental results well. This serves as the theoretical base for the whole thesis and will be used to optimize the characteristics of EDFAs. A novel method based on a map of noise figure and gain is proposed to analyze efficiently the dependence of the noise figure and gain for EDFAs on the EDF length and the pump power. The characteristics of various EDFAs are studied and compared.Secondly, some important parameters are introduced to describe the characteristics of EDFAs. The methods and the experimental setups for measuring the gain and noise figure of an EDFA are emphasized. We introduce how to measure the characteristics of each component of an EDFA, especially the gain and absorption coefficient of an erbium doped fiber.Thirdly, four types of simple and novel L-band EDFA structures with low noise, high gain and low gain ripple are proposed to satisfy the requirement of a DWDM system. They can be classified into two categories. In the first category, a single ASE pumping is served asa secondary pump. This category includes the following three types. Type: a new construction using a fiber Bragg grating in an unpumped EDF section at the input side. Type: a new structure of L-Band EDFA with two-stage pumps, which utilizes the forward ASE as a second pump.

本论文本着科技创新、服务于生产实践的精神，以设计价格低廉，性能优越、结构合理简单的L-band EDFA为目标，依托浙江省科技厅重大科学基金资助项目(001101027)和浙江大学振兴教育计划资助的全光网络的搭建—《光通信技术》课程实验建设项目，展开了如下工作：首先，介绍了掺铒光纤放大器的工作原理，归纳总结了基于速率方程基础的EDFA的各种理论模型，分析比较了各个模型的特点和适用场合，最终选择完善的Giles理论模型作为本论文分析设计EDFA的理论基础；针对实际实验条件提出了修正的EDFA模型的数值计算方法；创新地提出了增益—噪声系数全局分析法，直观有效地分析了EDFA的增益和噪声系数与掺铒光纤长度和泵浦功率的依赖关系，并对各种EDFA的性能作了全面的比较；第二，介绍了掺铒光纤放大器特性参数的定义与测量方法，重点介绍了噪声系数和增益系数的测量方法及实验装置；介绍了组成掺铒光纤放大器各组件的特性测量方法，重点介绍了测量掺铒光纤参数的方法和实验装置；第三，针对WDM系统对L-band EDFA谱平坦、低噪声、高增益的要求，我们创新地提出了四种不同的L-band EDFA结构，按设计思路可以分为两大类：一类是基于单抽运二级泵浦法，这一类包括在未泵浦掺铒光纤的输入端插入一根布拉格光纤光栅的两段L-band的EDFA的新结构；基于前向ASE光作为二级泵浦源推动下一级EDF工作的泵浦分配、两段级联L-band的EDFA的新结构；基于单根光纤光栅、泵浦分配、两段级联的EDFA；另一类则是基于同时应用前后向C-band ASE作二级泵浦源的双抽运法，如基于前后向ASE光作为二级泵浦源的三段级联L-band的EDFA的新结构。

The information includes combustion, valve-open and valve-close information. But this signal also contains interfering noise, like exhaust noise and other noise eradiated from the other part of the diesel engine, and the frequency composition of useful signal and interfering noise are largely overlapped in the frequency band under 20 KHz.

但是提取的缸盖噪声信号中也含有柴油机工作时产生的排气噪声和机体其它部位辐射噪声等干扰信号，且干扰信号与有用信号的频率成分在20 kHz以下的频带内重叠在一起。

In view of the concrete crack image characteristic, it emphatically discussed the recognition system three core issues. Firstly, it particularizes image preprocessing technology for reducing noise of concrete crack image. On the base of anglicizing the noise of specimen crack image and the characteristic of the noise , it propose the scheme that a hybrid filter will be used to reduce noise and introduce the principle of a hybrid filter.

随后，针对混凝土裂纹图像的特点，着重讨论了识别系统的三个核心问题：首先，详细讨论了对混凝土裂纹图像进行降噪的图像预处理技术，在分析了试件表明裂纹图像噪声的基础上，结合试件裂纹图像噪声的特点，提出组合滤波器的降噪方案，并介绍了组合滤波器的原理。

Increasing the input noise may increase the signal-to-noise ratio of the output response V(t within the element's parameter region indicating that the periodic components of V increase as the input noise increases. The relationsip between the variation of the SNR of the V curve and the noise is similar to the that of the resonance.

结果表明：在一定的条件下，增大输入噪声的值不仅不降低输出响应信噪比；反而迅速增加输出响应的信噪比，使输出响应中周期信号的分量反而加强，而且输出响应的信噪比对于输入噪声的变化具有&共振&形状的曲线。

However, this is mostly true for signals we receive directly, like noise sources, and not so much for signals from broadcast stations coming to us through skywave propagation. I aim the antenna for minimum noise pickup, which results in the best signal to noise ratio. In some situations it is quite possible to fully tune out a noise source such as a TV or computer monitor.

喜欢听干扰台的有福了，VOA和干扰台的信号不会是一个方向来的，把环对准VOA信号最强的方向，那么在另外方向的干扰信号就会衰减，VOA来的斗争指示你会听得更清），我更感兴趣的是最小噪声拾取，这会带来会好的信噪比，在一些情况下，很有可能将电视或电脑带来的噪声剔出出去。

Finally it offers the analysis of the fault-tolerance system as well as its test verification.

这样，运行于空间环境中的系统的设计目标就是在保证系统实时性

However, it is still difficult to find out the real reason of the increase of the keratinized gingiva during the orthodontic extrusion whether it is due to the proliferation of the gingival tissue or to its elastic nature, that is because the proliferation of the fibroblasts as well as the connective tissue changes in volume and the intra-fibers spaces were all immeasurable in most of the studies.

然而，仍然难以找到真正的原因增加的角化牙龈在正畸挤压它是否是由于扩散的牙龈组织或其弹性性质，这是因为增殖的成纤维细胞以及作为结缔组织的变化量和内部纤维空格都是不可估量的，大多数的研究。