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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 effects of eccentric mass, damping, inertia force and gravity on the vibration amplitude were analyzed.

在此基础上，分析了质量偏心、阻尼、惯性力和重力对振幅的影响。

Result Compared with hole planting, the characters of plant height, tiller number, eustipes number and leaf size etc. of banana dasheen were good in row-planting, the yield could be raised by 4 501.0-16 132.5 kg/hm^2 with the increasing amplitude between 1.9% and 21.9%.

结果］与窝栽种植相比，行栽种植下，芭蕉芋的株高、分蘖数、茎节数和叶片大小等性状好，产量可增加4 501.0~16 132.5 kg/hm^2，增幅在

Results:DPOAEs amplitude decreased significantly and rapidly after decerebration and remained at the lowest levels for 2,5,10 min. DPOAEs gradually recovered to the previous levels with time delay.

结果：在避免体温和颅温下降、缺氧等情况下，豚鼠去大脑僵直后 2 min、 5 min、 10 min 的DPOAEs幅值显著下降， 30 min 开始逐渐恢复， 60 min 基本恢复到术前水平。

A detection method of double-threshold constant false alarm movement object on double-base synthetic aperture radar includes finalizing distance compression of various pulse-sampling, dividing orientation time to be multiple CPI, carrying out FFT in each CPI to enter orientation frequency domain, comparing data amplitude of frequency channel at external of clutter region with the first threshold and outputting point trace, making coagulation on point trace, making Hough transform in point trace domain and making decision of the second threshold.

本发明涉及一种用于双基地合成孔径雷达的双门限恒虚警运动目标检测方法，其特征在于：1对每个脉冲采样完成距离压缩；2把方位时间分割成多个相干处理间隔；3在每个CPI内做快速傅立叶变换进入方位频域；4把杂波区外的频率通道的数据幅度和第一门限比较做判决并输出点迹；5点迹凝聚；6在点迹域做Hough变换并做第二门限判决。

The spontaneous type 2 diabetes GK rats had a characters on increase of delitescence and reduce of amplitude of F-ERG every wave.

结果：(1)血糖升高6个月的GK大鼠的fERG随病程的延长各子波峰潜时增加，振幅降低。

Dynamic derivatives of a 60° delta wing and F-18 aircraft model are calculated by this method, and then the effects of the amplitude,the frequency and the change of angle of attack on the dynamic derivatives are studied.

对60°三角翼和F-18飞机模型进行动导数仿真计算，研究了不同振幅、频率及迎角变化对动导数的影响。

SP can affect the function of DRG neurons by activing the non-selective cation channels combining with its selective NK1 receptor. ATP depolarize DRG neurons and make some sodium channels closed so that the amplitude of action potentials and Vmax decreased which result in decreaced releasing of neurotrasmitters from DRG neurons, the way is same like GABA-induced presynaptic inhibition by activing the non-selective cation channels possibly combining with P2X2/3-receptor.

SP可能通过开放非选择性阳离子通道从而影响DRG神经元膜的兴奋性；ATP通过与P2X2/3-R结合开放非选择性阳离子通道，使得A类神经元膜预先去极化，引起膜钠通道部分关闭，动作电位幅值降低，斜率Vmax减小，使神经末梢递质释放减少，其作用与GABA介导的突触前抑制类似。

A general form of D-FOG has been proposed in order to lower the bias drift and several forms of that have been studied:(1) The Blake type in which a depolarizer is inserted between the polarizer and coil-coupler of D-FOG can suppress the intensity error but not change the magnitude order of the amplitude error.(2) The type with two Lyot depolarizers added in the ends of sensing coil can suppress efficiently the both errors.

为了减小D-FOG漂移，作者提出去偏陀螺的一般形式，并分析其中几种重要形式：（1）在偏振器与环分束器之间插入Lyot去偏器的Blake形式，可以有效地降低强度误差但不改变振幅误差的量级；（2）在传感环两端各插入一个去偏器可以有效地抑制这两种误差。

A novel amplitude sensitive optical heterodyne polarimeter with sourse of a Zeeman laser was setup. The aim was to measure the optical activity of a Quartz Cornu Depolarizer, OCD, and Twisted-Nematic Liquid Crystal, TN-LC, at high accuracy and of aqueous humor in rabbit, in vivo, compared with the test of the concentration of blood sugar, in vitro.

本实验利用极化光共路径光学外差干涉方式架设极化仪；此种光学架构特性在於其结构简单，光学外差共光路特性加上采用参考光得以大幅度的降低雷射以及环境所造成的杂讯，进而得到准确且高灵敏度的旋光性量测结果。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。