查询词典 increase speed

The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.

理论分析和试验研究表明： 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的，具有摩擦动力学的本质，任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响； 2中心轴向载荷作用下，载荷增大使球轴承的固有振动频率升高，载荷越大同样的载荷增幅引起的频率升幅减小，足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响； 3轴向和径向联合载荷作用下，径向载荷不大时球轴承振动的固有频率基本不变，但是可能引起变刚度激励的非线性振动，出现新的频峰，过大的径向载荷将使部分钢球脱离接触，使球轴承的振动和噪声呈现不稳定状态； 4润滑对球轴承的振动和噪声特性有重要的影响，良好的润滑对振动有明显的抑制作用，润滑不充分时，振动和噪声的水平会有明显增高，一定条件下还会激发接触副中的谐振，发出啸声，造成接触表面的伤害，无润滑干接触时，短时的运转就会损伤接触副表面，使振动和噪声迅速增大，并随时可能引发严重的磨损和卡滞失效；接触副润滑良好时，油膜的"刚化效应"使球轴承振动的固有频率有所提高，润滑剂中含有弥散性污浊时，振动的幅度总体升高，但弥散性污浊不会改变球轴承振动的频率特性；浙江大学博士学位论文：球轴承振动的研究 5低速时，球轴承振动的基本特征呈现不稳定状态，随着转速的提高，球轴承振动的频率特性趋于稳定，固有频率频峰升高； 6理论分析表明，干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动，振动的幅值与谐波幅值成正比，实际球轴承中钢球的分布不可能完全均匀，波纹度的激励作用会随时发生；润滑接触的分析表明，波纹度的任意谐波分量均能激励球轴承的振动； 7球轴承的几何和结构参数分析表明，球轴承尺寸越大，径向、轴向和角振动的固有频率越低；钢球中心圆直径增大，球轴承的径向和轴向振动的固有频率基本不变，角振动的固有频率有所上升，振动的幅频特性基本不变；径向游隙加大使球轴承的径向振动固有频率降低，轴向和角振动的固有频率有所升高，径向振动幅频特性的幅值升高，而轴向和角向降低；钢球的数量增多使球轴承振动的固有频率上升，幅频特性的幅值下降，径向振动的幅值下降最为明显；外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高，轴向和角振动的固有频率降低，径向幅频特性基本不变，轴向和角向幅频特性幅值升高；内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降，振动幅频特性的幅值均有升高； 8试验对比表明，传感器采用探针式安装时，由于探针接触副接触特性的影响，钡(量得到的球轴承振动信号有失真，采用专门设计和制作的试验球轴承，以固定式安装加速度计，首次测量得到了球轴承振动的真实信号，通过对振动信号的分析，验证了球轴承振动的理论模型； 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析，以样本长度的均方根值作定阶上界，FPE做判阶准则，给出的AR谱光滑，频率分辨率高，是球轴承振动分析的简便而可靠的手段； 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间，时间间隔，频率范围，同样是球轴承振动分析的可靠的手段，可用作球轴承故障诊断技术。

The results showed that the use of tourmaline could increase alcoholic fermentation speed of molasses, the fermentation speed kept increasing with the increase of the use level of tourmaline, however, as its use level was above 11 %, the increase of fermentation speed was inevident; the use of tourmaline had no side-effects on the content of the main impurities including methanol, n-propyl alcohol, isobutyl alcohol, isoamyl alcohol; though it had weight loss after a period of use, it could still promote alcoholic fermentation of molasses.

结果表明，电气石对提高酵母酒精的发酵速率有促进作用，随着使用量的增加，发酵速率也随着提高，当使用量超过11 %时，发酵速率的继续提高不明显；电气石对发酵过程主要杂质甲醇、正丙醇、异丁醇、异戊醇等没有影响；电气石在使用一段时间后，重量减轻，但仍有促进发酵的作用。

When the other parameters are fixed, the SSD can be decreased with the decrease of wheel infeed, the increase of wheel rotating speed and the increase of chuck rotating speed, and the increase of chuck rotating speed within a suitable range.

在一定的范围内，当其它磨削参数不变时，硅片的损伤深度随着砂轮进给率的增大而增大，随着砂轮转速的增大而减小，随着工作台转速的增大而减小。

The agitation power consumptions in boiling systems decrease uniformly with the increase of agitation speed, whereas the relative power demand (RPD-the ratio of agitation power input of HEDT for gassed system to that for ungassed system and under the same agitation speed) can maintain at a high level for high gas loadings even when the impeller is operating with a high impeller tip speed. The gas hold-up in the boiling system is much lower than that in the cold gassed system, and the gas hold-up in boiling system increases at first and then decreases with the increase of the agitation power consumption per liquid mass P(subscript m. It implies that the boiling three-phase system has a maximum gas hold-up point. The changes of nucleation site of vapour bubble and the character of suspension of the solid particles with the rotational speed of the impeller are responsible for those behaviors mentioned.

在沸腾条件下，搅拌功率消耗随着搅拌转速的增加有所下降，但HEDT桨具有较高的载气能力，即使在高叶端线速度下，相对功率消耗仍能保持在较高的水平；沸腾体系的气含率随单位质量流体输入功率的增加表现出先增后减的规律，即存在气含率的极大值，蒸汽成核位置和固体颗粒悬浮特性随搅拌功率增加而改变是造成上述行为的主要原因；沸腾体系中的气含率远远低于常温通空气体系。

The results indicate that in the synchronizing condition the MRF is unyielded, every point of MRF in the flow field has the same angular velocity. Under the slipping condition, with the increase of magnetic field or the decrease of slip speed, MRF may transfer from whole yield to partial yield. When the MRF wholly yields, the angular velocity of MRF increases nonlinearly with its radius, the non-linear distribution becomes more obvious as the magnetic intensity in the working gap increases. When the MRF partially yields, the yield region expands with the decrease of magnetic intensity or the increase of slip speed and the unyield region always reaches the driven rotor. The transfer torque of MRTD increases with the increase of the external magnetic field, but the transfer torque maintains a constant value approximately with the variation of slip speed at the same magnetic intensity.

研究结果表明，在同步工况下，传动装置流场中磁流变液未屈服，各点角速度相同；在滑差工况下，随外加磁场的增大和滑差转速的减小，磁流变液逐渐从完全屈服向部分屈服转变；磁流变液完全屈服时，磁流变液角速度随半径呈非线性增加，工作间隙中磁场越强，流场的非线性分布越明显；磁流变液部分屈服时屈服区域随外加磁场的增大而减小，随滑差转速的增大而增大，未屈服区与主动转子相连；稳态下磁流变传动装置传递的转矩随外加磁场的增加而近似呈线性增大，但在相同外加磁场下，传递转矩基本不随滑差转速改变而改变，表现出良好的恒转矩特性。

Psis: You must minimize the number and duration of fixations per line to increase speed.

一 概要：减少每行的注视次数，缩短注视时间以提高阅读速度。

The root factor is still the increase speed of economy and is showed that people's livings are becoming better gradually.

最根本的因素，还是经济增长速度，而且要体现在人民的生活逐步地好起来。

B Where the Load up/down program is not provided, the Engineer shall increase and decrease the speed in accordance with the speed increase and decrease procedure of each ship, and shall pay attention to the Load Indicator, the RPM of the Main Engine or RPM of the propeller shaft, CPP pitch, the speed

如已提供增减负荷程序，轮机员应根据速度增加和减少程序进行加减速，特别注意，负荷显示、主机转速、螺旋桨轴转速、可变螺距、船速等，避免突然加减负荷。

In order to increase speed control,we need to take the following two measures while fully utilizingthe adjustable nature of rotors in series-wound asynchronousmotor

在发挥绕线式异步电动机转子的可控性优势的基础上，提高调速性能需要从两方面着手

Use high- k dielectrics and transistors with the metallic lock, according to the estimations of Intelrepresentatives , will make it possible to increase speed by 20% in comparison with the existing processors of company.

利用高k电介质和晶体管的金属锁，据估计英特尔代表将有可能提高到20%的速度相比，现有处理器的公司。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。