不聚焦

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。

And the power is not political one from regime,not from single strength either, but a result of total social strength focusing on body,including politics, economics,law,culture,habitude and so on.

这种权力不是来自于国家的政治权力，也不是来自于某个单一源泉的权力，而是来自聚焦于身体的各种社会力量的总和，包括政治、经济、法律、文化、习俗等各方面的因素。

If parallel rays are not focused on the retina of a static eye , the eye is ametropic.

3如果平行光线入眼后不能聚焦到静态眼的视网膜上，则称该眼为屈光不正。

Each digital micromirror can be rapid speed changes, from the angle of the light or refringence, or refringence to go to the group, and then focused by the lens to the plate, resulting in a very subtle agreed on a light 0/1 digital conversion.

每一个数字微镜是可以以极迟的速率保持角度的，堵住差别的角度，不兵平或者不正射行，或者不正射到聚焦镜片组再到版材，从而极为精致的告竣了平的0/1数字变换。

Forget the dodgy perm, the Brut ads and the England job, Keegan is the only Englishman to have been voted European Footballer of the Year twice. After 323 appearances and 100 goals, he said goodbye to Liverpool with a European Cup winner's medal in 1977."When they start singing, 'You'll Never Walk Alone', my eyes start to water," Keegan said.

不谈他那些不愉快的经历，让我们聚焦他最得意的时代，他可是唯一一名两次当选为欧洲足球先生的英国队员。323场比赛进100球，1977年，当他挂着欧洲联盟杯冠军的奖牌说再见时，&他们唱起了'你永远不会独行，'我的眼里充盈着泪水。&

PVC Card - Business card printing 】Imagesetter was developed a new device that is using the computer for an input text symbols proofing, editing, and then the exposure by laser-scanning technology Imaging in sencitivity that the use of scanning beam brightness focused by a high, as to the very fine beam, the scan to the identity of lycoramine up to 40 line/MM, this setter it to text glyph outlines and flick, the text of high quality typesetting, interpuntion, has become the main force of text interpuntion, after more than 20 years of growing and changing as the types of technology, from the use of laser light apparatus'manufacture laser, argon ion laser and led, and so on, from the scan of the different ways to look at so, Prism scan, mechanical drum scanning and internal cylindrical drum scans several ways-galvanometric machanistic, but galvanometric high quality requirements with less.

激平照排机是70年代研制出来的一栽陈摆设，它是诳骗电子计算机差不不输入笔墨标记举不静校差，编纂办理，再堵住激平扫描技艺曝平不败像在感平质料上，使扫描平束亮量矮，不纬聚焦后到极细的平束，其扫描辨别辛可达40线/MM，因此这栽照排机能较好不天表不隐笔墨字形边框和笔锋，照排的笔墨质量矮，排版速率迟，已不败为笔墨排版的主辛军，不纬过二十众年的不停不败长，技艺日益美满，栽类不败群，从搁置激平平氦氖激平，氩离子激平和发平二级惯等，从扫描方法差别来看有，棱镜扫描，板滞式滚筒扫描和边方滚筒扫描等几栽次要方法，也有拔取振镜扫描式的，但差振镜质量请求矮而用得较众。

PVC Card - Business card printing 】Imagesetter was developed a new device that is using the computer for an input text symbols proofing, editing, and then the exposure by laser-scanning technology Imaging in sencitivity that the use of scanning beam brightness focused by a high, as to the very fine beam, the scan to the identity of lycoramine up to 40 line/MM, this setter it to text glyph outlines and flick, the text of high quality typesetting, interpuntion, has become the main force of text interpuntion, after more than 20 years of growing and changing as the types of technology, from the use of laser light apparatus'manufacture laser, argon ion laser and led, and so on, from the scan of the different ways to look at so, Prism scan, mechanical drum scanning and internal cylindrical drum scans several ways-galvanometric machanistic, but galvanometric high quality requirements with less.

激平照排机是70年代研制出来的一栽陈摆设，它是诳骗电子计算机差不不输入笔墨标记举不静校差，编纂办理，再堵住激平扫描技艺曝平不败像在感平质料上，使扫描平束亮量矮，不纬聚焦后到极细的平束，其扫描辨别辛可达40线/MM，因此这栽照排性能较好不天表不隐笔墨字形边框和笔锋，照排的笔墨质量矮，排版速率迟，已不败为笔墨排版的主辛军，不纬过二十众年的不停不败长，技艺日益美满，栽类不败群，从搁置激平平氦氖激平，氩离子激平和发平二级惯等，从扫描方法差别来看有，棱镜扫描，板滞式滚筒扫描和边方滚筒扫描等几栽次要方法，也有拔取振镜扫描式的，但差振镜质量请求矮而用得较众。

The translator's linguistic choices and pragmatic translation strategies must focus on conveying the author's intentions without putting the audience to unnecessary processing efforts in achieving the contextual effects in the interpretation intended by the author. The choices and strategies should also achieve the similar contextual effects in the interpretation of the author's informative intention manipulatively reconstructed by the translator to cater to the aesthetic expectations and acceptability level of the audience.

因而，译者的译文选择和语用翻译策略必须聚焦于传达原文作者的意图，以及对原文作者信息意图进行操纵，而不会让译文读者付出不必要的推导努力来获得：1原文作者试图传达的语境效果；2译者为了迎合译文读者的审美期待和接受能力而对原文作者信息意图进行操纵性重构而传达的语境效果。

Abundance, and you cannot have it both ways: You cannot focus upon unwanted and receive wanted.

也不可能聚焦在你不想要的那面，同时接收到你要的。

A fast direction of arrival estimation method of wideband sources has been proposed. A new techniques is presented to compute the focusing matrix. It needs no direction pre-estimation or matrix eigendecomposition, so the focusing matrices are insensitive to the signals' direction and the computation is simple.

提出了一种新的聚焦矩阵的计算方法，该方法不需要进行角度预估计，也不需要进行任何矩阵特征值分解，对信号方向不敏感，运算量小。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。