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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。

After the supernova SN1987A exploded for more than a decade, the surrounding gas ring gradually brightened up.

超新星SN1987A爆发后十多年，周围的气体环反而逐渐变亮。

The alarm valve should be installed vertically. When there is a fire in the protected area, temperature rises up, pressed water jet from sprayer, and the alarm valve is initiated to jet water onto fire. After 5-20 seconds, the delayer will sent out alarming signal to ring the bell for fire extinguishing.

当保护区某处发生火灾时，环境温度升高，闭式喷头的维护敏感元件破裂，压力水从喷孔口喷出并自动启动报警阀将水直接喷向火灾发生区域，延迟器延时5-20秒后发出报警信号，带动警铃以达到报警、灭火的目的。

The following are main points in the thesis.(1) On the basis of widely researching of the domestic and overseas references, there are four types of depolarizers being summed up and introduced in this thesis, the four types are spatial averaging depolarizer, time averaging depolarizer, fiber ring depolarizer and spectral averaging depolarizer.

本论文主要完成的工作是：(1)在查阅了大量的文献的基础上，总结了四种类型的退偏器，空间偏振态平均退偏器、时域平均退偏器、光纤环退偏器、光谱平均退偏器，并分别对四种类型的退偏器的工作原理进行了深入的研究，为每种退偏器的设计方法建立了数学模型。

The main contents include: Setting up a theoretic vibration decreasing model of ERSFD and deriving its differential equation; Analyzing and comparing the features of ERSFD, SFD and Porous Squeeze Film Damper , and finding out that SFD and PSFD are the special examples of ERSFD; Giving an over-relaxation differential algorithm for the solution of the oil film force of ERSFD; Deriving the differential equations of the elastic ring deformation with and without tension and solution method.

给出了求解ERSFD油膜力的超松驰差分迭代格式和算法。

Wake up one morning and just ignore everything else but getting to London, get lost in the Underground, ring the doorbell at Sheva's apartment, and when Sheva is standing on the other side of the doorframe, say I love you.

早上起来，什么也不管，一股脑跑到伦敦，然后迷失在地铁嘈杂的人群中，敲sheva的门，对来开门的sheva说："我爱你，告诉我你还爱不爱我。"

The second part, with the theories of the first part for guide, pass a software ANSYS to imitate the napu big bridge main arch ring's ultimate load carrying capacity under well-distributed loads, in imitating process, distinguishing the emulation by three ways: 1, the characteristic value emulation, 2,the geometric nonlinearity emulation 3,double nonlinearity emulations, and sum up the frame of the order flow within various emulation process, so that the good leading function can be provided with related calculations.

第二部分，以第一部分的理论为指导，通过大型有限元软件ANSYS来模拟南浦大桥主拱圈在均布荷载作用下的极限承载力，并探究主拱肋在极限荷载作用下的破坏过程。

The dried materials after the de-watering will go up with the heat-air flow. The step rings will stop and keep the big particles. Small particles will be discharged out of the drier from the ring center and will be restored by the whirl separator and dust remover. The not-fully-dried or big piece materials will be sent to the wall of the equipment by centrifugal force function and be smashed again after they fall down to the bottom.

脱水后的干物料随热气流上升，分级环将大颗粒截留，小颗粒从环中心排出干燥器外，由旋风分离器和除尘器回收，未干透或大块物料受离心力作用甩向器壁，重新落到底部被粉碎干燥。

To change the pick type, the cutting depth etc, so as to observe their influences on the deformation and destruction law of coal body; To adopt octagonal ring dynamometry made by ourselves and signals picking up system of multi-channel, low frequency and high-accuracy so as to monitor the cutting force in coal cutting course; To adopt the high-speed photography method, so as to shoot the cutting course and analyze the law of shaping.

改变截齿类型、截割深度等，观察对煤体变形破坏的影响；采用自制的八角环测力仪和多通道低频高精度信号拾取系统对截齿截割煤体过程中的截割力进行了在线监测；采用高速摄影的办法拍摄截割过程，分析变形破坏的规律。

As China's economic center of Shanghai, Pudong with the re-emergence of full-scale development, now the Shanghai people most likely to have association with the image is no longer just the Bund, the International Hotel, there are Lujiazui financial district many of the super high-rise buildings, the Shanghai Grand Theater, the Oriental Pearl TV Tower, Jinmao Tower, inner ring elevated road will constitute a new urban landscape of Shanghai; and the people of Shanghai are full of confidence that the city of their spirit and determination to catch up with Hong Kong then let all Chinese people believe that Shanghai's re-emergence in the world will not be too far off.

作为中国经济中心的上海浦东的重新出现的全面发展，现在的上海人最有可能与形象已不再仅仅是外滩，国际饭店，还有陆家嘴金融区的许多超高层建筑，在上海大剧院，东方明珠电视塔，金茂大厦，内环高架路将构成一个新的城市景观的上海和上海人民充满了信心，该城市的精神和决心赶上香港然后让全体中华儿女认为，上海的重新崛起在世界将不会太遥远。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。