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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。

At present under the socialist market economy condition, completes the enterprise staff thought political work the key is the Central Party Committee 17 big spirits in every sense of the term implementations basic unit Since the specially reform and open policy, has had many head of undertaking, deceives both superiors and subordinates works for one's own interests under the guise of working for the public, thought the present does not have the movement, in the waist the animal pen axe, the fan which in the hand takes, often on greatly sends the arms, teaches whips the staff, often on to the authority coerces the staff, simply not staff when the person looked, the wages casually decides, bully softly, is hard feared, pays out the wages not to have the pay list, wants to give how many to give how many, Sunday does not let the staff rest, does not pay adds the spot to spend If you offer an opinion to him, regards you is the thorn in one's side, the thorn in the side, does everything possible to carry on retaliates you, and direct descendant wilfully tolerates using the hand in authority to oneself, to give the green light to something, to holds the different political view greatly to open killing They use in the hand two "magic weapon" to benefit as the third party in a dispute, deceive both superiors and subordinates flatter the higher authority, exploits power, violates the country head of undertaking the cadre relative about to forbid in this enterprise to be engaged in production management the stipulation Also uses in the hand the authority private full center pouch, is greedy, does everything possible to concoct pretexts makes the forged account, high keeps off the office supplies with the government money purchase modern age to converge the oneself to have, makes the forged account to reimburse the beach person cost, digs national the corner of a wall Then receives using the duty gives the sales commission,包产 outside the package exits the enterprise outside, fishes for the wealth, even allies the annual bonus, violates the country and the enterprise stipulated, then 参股using the duty manages the enterprise But greatly gives the discount in the staff benefit treatment aspect, in 工资分 is joined to greatly makes the issue, drills the national policy spatial, borrows the wage reform is the excuse, seeks the benefit for own clique, borrows the work then to provide the special sedan car for the enterprise basic unit leadership, all expenses completely are responsible by the unit, to become not to pay the solid private sedan car The party and the country stressed repeatedly that, strictly prohibits the leading cadre to exploit power, but such stipulation into head of undertaking cadre's neglected advice, really it may be said in has the policy, gets down has the countermeasure If the country does not carry on effective supervising and managing to the enterprise, does not carry on the strengthened management, gets down for a long time, they can depend on right and not the improper income become the millionaires and surely the wealthy man, the state asset can massively drain, but government's policy can become a mere scrap of paper, loses it in common people's prestige Let these clothes eating insects embezzle national the property, thus causes the enterprise to move towards goes out of business, such example is too numerous to cite individually The working class is the national master, such formulation until now is does not have the question, but present working class's actual condition how?

目前在社会主义市场经济条件下，做好企业职工思想政治工作的关键是把党中央十七大精神不折不扣的贯彻到基层。特别是改革开放以来，有不少的企业领导，欺上瞒下假公济私，认为现在没有运动，腰里苄着斧子，手里拿的扇子，动不动就大发干戈，训策职工，动不动就以权力要挟职工，简直不把职工当人看，工资随便定，欺出软，硬出怕，发工资没有工资单，想给多少给多少，星期天不让职工休息，不付加斑费。如果你给他提意见，就视你为眼中钉，肉中刺，想方设法进行报复你，利用手中的权力对自己和嫡系任意纵容，大开绿灯，对持不同政见者大开杀界。他们用手中的两件"法宝"渔翁得利，欺上瞒下讨好上级，以权谋私，违反国家关于企业领导干部亲属禁止在本企业从事生产经营活动的规定。还利用手中的权力私饱中囊，多吃多占，想方设法巧立名目做假帐，用公款购买现代高挡办公用品归为己有，做假帐报销滩人成本，挖国家的墙角。利用职务之便收授回扣，把企业外包产品外包出去，从中捞取钱财，甚至加盟人股，违反国家和企业规定，利用职务之便参股办企业。而在职工福利待遇方面大打折扣，在工资分配上大做文章，钻国家政策的空，借工资改革为借口，为自己的小集团谋利益，借工作之便为企业基层的领导配备专门的小轿车，一切费用全部由单位负责，成为名不付实的私家小轿车。党和国家一再强调，严禁领导干部以权谋私，而这样的规定成为企业领导干部的耳旁风，真可谓上上有政策，下有对策。如果国家对企业不进行有效监管，不进行强化管理，长期下去，他们会靠正当和不正当的收入成为百万富翁和千万富翁，国有资产就会大量流失，而政府的政策就会成为一纸空文，失去其在老百姓中的信誉。让那些蛀虫侵吞国家的财产，从而使企业走向倒闭，这样的例子不胜枚举。工人阶级是国家的主人，这样的提法至今是没有问题的，可是现在的工人阶级的实际状况又如何呢？

The sufficient conditions to guarantee robust exponential stability for the closed-loop systems are obtained based on Linear Matrix Inequality, moreover, the approach of design of robust H# output feedback controller is introduced.3 The problem of reliable H# control for a class of Lur"e systems with polytopic uncertainties is studied when all control components are operational as well as when some control components experience failures, the design approach of reliable H# controller is also obtained.4 Considering a class of uncertain Lur"e singular system with time-delays, the problem of robust stability is investigated based on Barbalats Lemma and nonsingular linear transformation of model reduction.

针对一类不确定Lur'e奇异时滞系统，基于Barbalat引理以及非奇异降阶变换，讨论了Lur'e奇异时滞系统的鲁棒稳定问题，提出了鲁棒H_∞状态浙江大学博士学位论文反馈控制器的设计方法。5、针对一类具有饱和执行器的不确定Lur'e奇异系统，提出了时滞依赖的鲁棒稳定与鲁棒二次镇定的充分条件，所的结果不需要参数的整定。6、针对任意协方差有界的有色噪声，讨论了一类不确定Lur'e奇异系统的鲁棒凡滤波问题，得出了鲁棒几滤波器设计的充分条件。7、针对一类不确定Lur'e时滞系统，通过线性变换，把它转换成奇异系统，根据奇异系统鲁棒控制理论所得出的鲁棒稳定与鲁棒镇定控制器设计的充分条件具有很小的保守性。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。