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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。

Lasting Chanel, Chanel has already become the most well-known brand of world;Double the classic LOGO of the C will inherit a vogue forever popular, never be absent.The Chanel madam is born in 1883 and passes away in 1971, the COCO is her childhood name, although she lees us for a long time, the style of its classic always that time still the founder of boundary.She most shows affection for to be with black and white carry on beautifully changing magically and carry out a kind of absolute pleasant impression and perfect harmony.She lee many become the direct mind tutor who guides to spread this ages to popular viewpoints, she think what the United States point is inside outside all beautiful, although spread to continuously put forth new ideas, the style can never be eliminate.In the meantime her believe deeply is the be"simple" st way which lets the fine texture present and her classic design for lee include:NO.5 perfume, be the inclined line soft, double color shoe, black and small dress etc., the accessories of classic is the leather that the assertion lets woman's hands vacate to wear the handbag that the chain take, she show affection for of the mountain camellia also still blooms in the dinner of silk ans stain the pack the ectype pattern.Chanel although from clothing house, as early as 1925 she starts entrust to produce a little amount rouge, lipstick and skin care products and provide oneself and the guest use, display just in the Chanel dress boutique, these merchandises he already beat up the CHANEL name, the perfume of the No.5 appears on market in 1921, beginning go toward perfume, cosmetics development, perfume and cosmetics he become Chanel performance very outstanding item now, separate to release a kind of new perfume for a while each time, in the aspects of leading cosmetics fad, Chanel also takes a lot of trouble, the quarterly releases a new merchandise each time, and lead the quarter don't sell!

永远的香奈儿，香奈儿已经成为全球最知名的品牌；双C的经典LOGO将永远袭卷时尚流行、永不缺席香奈儿夫人出生于1883年、逝世于1971年，COCO是她的小名，虽然她离开我们很久，但是其经典的风格一直是时尚界的鼻祖她最钟爱用黑色与白色进行美丽的幻化，实现一种绝对的美感以及完美的和谐她留下许多对流行的看法，成为引导这个时代流行的直接心灵导师，她认为美指的是内外皆美，虽然流行不断推陈出新，但是风格永远不会被淘汰香奈儿虽然由服装起家，但早在1925年她就开始委托生产少量腮红、口红和保养品，供自己和客人使用，仅在香奈儿服饰精品店陈列，但这些商品已打上CHANEL名号，1921年五号香水上市，开始往香水、化妆品开发，现在香水与化妆品已成为香奈儿表现相当出色的项目，每隔一阵子就推出一种新香水，在领导化妆品流行方面，香奈儿也煞费苦心，每一季推出一项新商品，而且过季不售！

The present invention is one opening hardware safety platform enclosed inside one casing and with relaxed application environment, powerful attack resistance and high reliability. The present invention has several enciphered algorithms, supports several kinds of application service, has high versatility, and may be used also in ciphering server, VPN ciphering gateway, SSL safety gateway, safety router, hardware fire wall and other safety devices.

本发明是一个开放式的硬件安全平台，组件封装在一个机壳内，对应用环境的要求低，抗攻击能力强，可靠性高；由于本发明提供多种加密算法、支持各种应用服务，通用性极高，也可以广泛应用于加密服务器、VPN加密网关、SSL安全网关、安全路由器、硬件防火墙等安全设备中。

While on duty, Customs officer will be neat, clean and businesslike; uniforms must be free from tears, or other visible blemishes; the Customs badge and epaulets must be worn; black footwear will be kept clean; hairstyles will not interfere with the proper performance of duty, hair will be neat, clean and present a gloomed appearance; necklaces and jewelry shall not be worn by uniformed Customs officer.

执勤时，海关关员干净利落、忙忙碌碌，制服不得有破损或其可见的污点，他们必须戴上徽章和肩章，黑色的鞋子时刻保持干净，发型不得影响到工作时的正常活动，头应该整齐、干净、精心梳理，身着制服的关员不能戴项链及首饰。

Furthermore, the present model is employed to compute the wave field in the inner area of the deepwater channel jetties in the Yangtze River Estuary. Results demonstrate that the present model, which takes into account energy dissipation and the partial reflection of waves, can be used in the relatively large harbor basin, not only simple and convenient to conduct but also provides enough accuracy to satisfy the demand of engineering design.

同时从对长江口深水航道一期工程导堤内侧水域波浪场的计算结果看，本文的计算方法能够应用于较大范围的港内水域的波浪数值计算，并考虑了底摩阻耗散和边界不完全反射的影响，计算简便，精度满足工程应用要求。

This line of public figures indicated that stops issuing the primary cause is holds the euro investor quantity to be few at present , and the present US dollar revalues continually , the euro faced with the big depreciation pressure , the prospect is not very bright .

该行人士表示，停发的主要原因是目前持欧元的投资者数量较少，且目前美元持续升值，欧元面临较大贬值压力，前景很不明朗。

Any person who, being or having been a Crown servantmaintains a standard of living above that which is commensurate with his present or past official emoluments; oris in control of pecuniary resources or property disproportionate to his present or past official emoluments, shall, unless he gives a satisfactory explanation to the court as to how he was able to maintain such a standard of living or how such pecuniary resources or property came under his control, be guilty of an offence.

二香港「防止贿赂条例（ Prevention of Bribery Ordinance ）」第十条规定：「任何现任或曾任官方雇员的人维持高於与其现在或过去的公职薪俸相称的水准；或控制与其现在或过去的公职薪俸不相称的金钱资源或财产，除非就其如何能维持该生活水准或就该等金钱资源或财产如何归其控制向法庭作出圆满解释，否则即属犯罪。

To make a comprehensive view of metapopulation researches, we folly analyze and summarize the present concepts, theories and models of metapopulation in this paper, which primarily includes the dynamical models and simulation approaches of single and competitive metapopulations. Based on the Levin's patch occupant model, the center framework of metapopulation researches, primary principles and mechanisms are discussed. First, Levins rule: the fraction of empty patch will remain constant with habitat destruction as long as metapopulation survives. This rule implies that empty patches have determinant effects on persistence and conservation. Second. Allee effect of metapopulation is incurred by establishing difficulties and dispersal costs, which is important to the studies of reserve area and the minimum available metapopulation size. Third, we analyze the rescue effect that immigrants can reduce the extinction risk of the presented local population. Rescue effect can leads to the improvement of metapopulation sustainability and the decrease of fraction of empty patches. Fourth, the coexistence mechanism of two competing metapopulation is discussed, which suggests that competition-colonization trade off may be prevalent in competing systems. Finally, extinction debt ob tamed from coexistence mechanism is given, which depicts the lost of species richness in the future for the current habitat destruction. After theoretical discussion, we present two popular simulated approaches in metapopulations: probability transition model and stochastic process model.

为了能总观集合种群进展的全局并开展进一步的工作，首先对集合种群的已有概念、理论和模型做了全面的分析和总结；其次对集合种群的发展和概念进行了探讨，以集合种群模型的中心框架：Levins的斑块占据模型为基础，展开对其它原理、效应和机制的探讨；主要包括了Levins原理，即当生境进到破坏时，空斑块比例在集合种群灭绝前保持不变，然后还分析了Allee效应（集合种群的Allee效应主要是由于建群困难和扩散损失造成的）；第三，分析了援救效应：迁人个体可以降低斑块中现有局域种群的灭绝风险，援救效应会增强集合种群的生存力，使空斑块比例下降第四，探讨了两竞争集合种群的共存机制，即竞争－侵占妥协，其共存机制为空间生境中物种共存提供了有力的理论解释。

The company researches and develops the main camp product is thecollection solar energy gentle breeze can to body wind, the energy oflight series street light, the garden lamp, the lawn lamp and thetraffic signal indicator lamp, the product core disposition module bethe present performance best, the technical maturest wind, the energyof light supplementary generating system and the highly effectiveenergy conservation electricity photosource, the product has thequality to be reliable, the highly effective energy conservation, thesecurity environmental protection, simple and the artistic manymerits, installs when may avoid excavating with the shop line, isgreen environmental protection energy conservation illuminationproduct which the present country advocated vigorously.

公司研发的主营产品是集太阳能和风能于一体的风、光能系列路灯、庭院灯、草坪灯及交通信号指挥灯，产品核心配置的组件均是目前性能最好、技术最成熟的风、光能互补发电系统和高效节能的电光源，产品具有质量可靠、高效节能、安全环保、简便及美观的诸多优点，安装时可避免开挖和铺线，是目前国家极力提倡的绿色环保节能型照明产品。公司秉着&科技领先、质量第一、客户至上&的服务理念，着力打造天时。

L Qualified faculty members can be drawn from the ranks of present and past club presidents, present and past R.I. officers and even non-past presidents with skills/experience in special areas

l 适任的教员可由扶轮社现任的社长及前社长、国际扶轮现任的及前职员中选任，以及甚至那些非前社长而在特殊领域有技巧/经验的人亦可担任

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。