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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。

Clay minerals in 15 surficial samples and 5 profile samples from the Yangtze Delta plain were analyzed by X-ray diffraction.

采用XRD研究了长江三角洲地区15个表层样品和5个剖面样品中的粘土矿物。

After disinfection and medical activities before, samples were taken from three points in a diagonal of a relatively closed space with area not more than 30 square meters. In general, one point was from diagonal center, and the other two points from the two ends with one meter distance to walls. When the area exceeded 30 square meters, samples were collected from five points, one was from the center, and the other four points from four angles with one meter distance to walls, and the altitude was 80-150 cm from vertical distance to the ground. The total number of microbes not more than 200cfu/m^3 was considered qualified.

消毒后和进行医疗活动之前，相对封闭的空间，面积≤30平方公尺时，在一条对角线上取3点采样，一般是中心和两端距墙壁1米处各取1点；面积＞30平方公尺时，应取中央及四角距墙壁1米处共5点采样，布放高度为垂直地面80cm~150cm，微生物总数≤200cfu/立方公尺为合格。

With extension of keeping in storage diastase number of honey in six samples show different varying rule: the DN of the superior samples descend distinctly, but that of the inferior change not too obviously.

且随着放置时间变长，几种蜂蜜呈现出不同的变化规律：优质品A、B、F的DN值下降明显，而劣质品C、D的DN值变化不大。

The dielectric relaxation is non-Debye dielectric relaxation when slow polarization effect cannot be neglected in the samples. And from low frequency to radio frequency, the complex ε of the samples is not consistent with Kramers-Kroning relation.

实验表明：介质中慢极化效应的存在使得其介电弛豫普遍都不是德拜型的；在超低频至射频的广阔频段，样品的复ε不满足Kramers-Kroning关系。

This dissertation introduces x-ray diffractometer, and measured the C/W supermirror samples. The results show that the optical character of these samples is in good agreement with the calculated results.

本文采用了X射线小角衍射的方法测量了超反射镜的光学性能，反射镜的反射率曲线与理论计算结果符合较好，完全满足实际需要。

Simulation experiments make sure that the dilatometer is able to detect the expansion changes in low temperature. The high temperature reheating process with dilatometer analysis indicate that the firing temperature are little higher than 900℃ for one sample and lower than 900℃ for other five samples with firing temperature ranges of 550~650℃, 650~750℃ and 750~900℃. The results from mineral composition analysis of the samples by X-ray diffraction provide further evidence of the reliability of the thermal expansion measurement.

模拟实验表明，所采用的热膨胀仪能适应低温法测温实验；用热膨胀高温法测出早期陶片中有一块样品原始烧成温度略高于900℃，其余5块样品皆低于900℃；通过热膨胀低温法较为准确地测出这五块样品原始烧成温度是分别介于550~650℃、650~750℃、750~900℃三个范围，而X射线衍射分析结果从物相成分的角度证明了测温结果的可靠性。

The dentofacial characters of Class II division 1 in our samples,there were not only the different size between sex but also the wholeappearances. Because of that we defined there was sexual dimorphism in our samples.

的研究样本中除了有大小不同的差距，另外在整体的表现上也有性别的差异，因此我们认为本研究样本存在两性二形的情况。

RESULTS: We tested 778 samples and found 14 discrepant samples between the 2 assays.

结果：我们检测了778例临床标本，发现各采用两个检测方法学的检测结果出现了14例的差异。

The optimized weight is arrived by weighted the minimum variance distortionless response weights of these samples with their post probabilities. In addition, the samples with little post probabilities will be resampled and it improves the robustness of beamforming effectively.

在该算法中期望信号的波达方向被看成一个由若干样点组成的随机变量，利用后验概率对这些样点的最小畸变响应波束成形权值进行加权来取得优化的权值，并对小概率样点进行重采样，有效地提高了波束成形系统的鲁棒性。

But this is impossible, as long as it is engaging in a market economy, there are risks in any operation.

但是，这是不可能的，只要是搞市场经济，是有风险的任何行动。

We're on the same wavelength.

我们是同道中人。