查询词典 signal noise ratio

Better denitrification efficiency could be obtained with adding amylo and the removal ratios of ammonia nitrogen were at least 93%. The removal ratio of TN increased gradually with the increasing of C/N ratio. When C/N ratio was 10, the best removal ratio of TN could reach 80.81%. But when C/N ratio added on 12, the ratio removal of TN was not increased only keeping about 75%.

投加淀粉调整C/N比，系统能取得良好的脱氮效果，氨氮的去除率均在93%以上，随着C/N比的增加，TN的去除率也逐渐的增大，当C/N为10时，TN最高去除率能达到80.81%，但当C/N增大到12时，TN的去除率不再增大，只是稳定在75%左右。

When the gas flux is constant, the ratio of reduced resistance is improved with the increase of the water stream velocity. However, the relationship between the gas flux and the ratio of reduced resistance is more complex. When the water stream velocity is constant, if the gas flux is small in contrast, the effectiveness of reduced resistance is not obvious. But when the gas flux increased, the jetted gas will form """"archform"""" which will augment the shape resistance. In this condition, resistance could not be reduced and could even be increased, if the gas flux continues to be increased. So that there needs setting a baffle called step, which introduces the jetted gas into the turbulence boundary layer. In this case, the shape resistance may be fairly great. Besides, the waterline of model has also some effect on the ratio of reduced resistance, which acts on the size of wave. If waterline is deep, the wave could not affect the deployment of microbubble layer, so there is almost no effect on ratio of reduced resistance. However, the wave would affect distributing of microbubble layer under the model so that the gas could leak out from the two sides of model and directly affect the ratio of reduce resistance if the waterline is very small. Whether installing the dashplate or not has also the great influence on the effectiveness the ratio of reduced resistance. From the results of experiment, conclusion is that adding dashplate will greatly improve the effectiveness of reduced resistance.

当喷气量一定时，水流速度增大，减阻率提高；喷气量与减阻率之间的关系比较复杂，速度一定时，如果喷气量较小，减阻效果就比较差，但当喷气量增大的话，喷射出的气体就会形成一个&拱度&，增加了船模的形状阻力，在这种情况下最好采取断阶喷气，把气体引入到湍流边界层中，在这种情况下，船模的形状阻力比较大；船模的吃水对减阻率也有一定的影响，主要表现在波浪大小上，如果吃水较深，波浪影响不到微气泡层的分布，对减阻率不会造成太大影响，如果吃水较浅，波浪就会影响到微气泡层在船模底部的覆盖情况，可能会有部分微气泡从船模两侧泄漏，这样就直接影响到了减阻效果；是否安装压浪板，对减阻率也有较大的影响，从试验结果可以看出，在船模尾部加设了压浪板时，减阻效果明显得到改善。

Results of pulling test reveal that the nominal strength ratio of corroded hot-rolled steel bar over uncorroded one is approximately equal to the ratio of maximum residual sectional area over the uncorroded one.And the rupture extension ratio of corroded hot-rolled steel bar is exponentially decreased with the maximum sectional loss ratio.The effect of stress concentration caused by corrosion pits has a significant influence on the decrease of rupture extension ratio but it is ignorable on the nominal strength ratio.

实验结果表明：锈蚀钢筋与未锈钢筋的名义强度比可近似取锈后钢筋的最大残余面积率，受锈坑应力集中的影响甚微；锈蚀钢筋的断后延伸率随最大截面损失率呈指数下降，受锈坑应力集中的影响显著。

Markstein length increases with the increase of dilution ratio when equivalence ratio is less than 1.4, and the flame stability tends to increase with the increase of dilution ratio. The ratio of unstretched laminar burning velocity with and without diluent is only related to the dilution ratio and is little influenced by the equivalence ratio.

丙烷－空气－稀释气混合气随稀释系数的增加，火焰传播速率和层流燃烧速率降低，在当量比小于1.4时，随稀释系数的增加，马克斯坦长度值增加，火焰前锋面的稳定性趋势增加。

The factors that influence the noise performance of lithium-based grease were researched,the cleanliness of grease is merely one of essential conditions to decrease noise,the particle size of lithium soap thickener is smaller,the noise performance of grease is better,and the low viscosity naphthene base oil has good effect to decrease noise,the polymer can improve lubricity and decrease noise.

研究了影响锂基润滑脂噪音性能的各种因素，润滑脂的清洁度只是降低噪音的必要条件之一，锂皂稠化剂的微粒越小，润滑脂的噪音性能越好，低粘度的环烷基油具有良好的降低噪音的效果，高分子聚合物可以改善润滑性能，降低噪音。

NB/ANL button. Pressing this button enables the built in noise reducing functions. There are: noise blanker only, both noise blanker and automatic noise limiter, and automatic noise limiter only.

NB/ANL button ：静噪/噪音自动限制器按钮，按下这个按钮产生减少噪音功能：仅是噪音抑制器；既是噪音抑制器又是噪音自动限制器；和仅是噪音自动限制器。

Firstly the dissertation analyses the reason of vibration and noise of the transmission gear and the box, drawing a conclusion that the change of gear mesh rigidity and transmission error are the crucial causation to engender vibration and noise of the gear-box; the main source of the noise is the syntonic noise in box vibration and noise.

本文首先分别分析了变速箱传动齿轮和变速箱箱体的振动噪声产生机理，得知产生变速箱传动齿轮振动噪声的主要因素是轮齿啮合刚度的变化和传动误差的影响；且在变速箱箱体振动噪声中自鸣噪声是汽车变速箱的主要噪声源。

Methods : The noise intensity and spect ral analysis were monitored with HS6288 noise inspector.Cumulative noise exposure was calculated according to noise intensity and working age. Testof Audio acuity was carried out for 931 noise exposure workers,who are with non - otopathy.

用HS6288 系列噪声分析仪监测作业场所噪声强度，并进行频谱分析，计算累积噪声暴露量；对某纺织厂接触噪声作业的无耳疾患的931人进行听力检测；用EpiData 建立数据库，SAS 软件8.0 统计包进行统计分析。

This method can make sure the structure radiant sound status in total noise and the detail phonate part quickly and correctly.(3) Study on the control mechanism of structure noise radiated from rotary machines, we build a common model of rotary machine structure noise analysis relied on the general characters of rotary machines. Based on this model, we analyzed various influence factors to structure radiant noise using the union of revolution and numerical calculation method. We found that the joint stiffness between the rotor and the frame is the most sensitive parameter of structure radiant noise by calculating and analyzing.

根据本文对于旋转机械结构噪声控制技术的研究结果和惯性振动筛工作的特殊要求，对有关参数的选择进行了讨论，并通过试验为降低惯性振动筛噪声找到了两个新的方法：即，在轴间相对运动要求不高的情况下，可以在激振器与筛体之间安装一组减振器，通过适当选取减振器参数，既可以使机体在工作频率附近获得稳定振幅，保证振动筛正常工作，又可以使机体的高频响应减小，降噪效果显著；反之，如果轴间相对运动精度要求(来源：1aABC论文网www.abclunwen.com)较高，可以采用空心滚动体轴承，在保证滚动体强度的条件下也可以获得较好的降噪效果。

This paper,through measuring and analyzing the noise sources in the hot-dip galvanization workshop of a steel tube plant,indicated that the operation of inner blowing tube is the major environmental source of noise pollution,studied the mechanism of air current noise for blow pipe,put forward comprehensive administer steps with sealing cap,pressure reduction,noise elimination and noise insulation.

噪声治理工程初步实施结果表明，内吹管噪声瞬时峰值降低了10~15dB，厂界噪声瞬时峰值降低了20dB以上，收到了良好的工程效果。

Hanna: That's over now, isn't it?

都结束了，对吗

You must be ill. You look so pale.

你一定是病了，你的脸色苍白。