中轴的

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。

According to the biaxial reciprocating gear-driven principle that presents by professor He guo jin in this thesis, the biaxial reciprocating cylinder gear reducer has been designed and interiorinput power of this reducer is forty watt.

本文根据何国金教授提出的两平行轴间多级圆柱齿轮来复传动原理，设计了一台两平行轴大速比来复传动圆柱齿轮减速器，其输入功率为40w，这种减速器中的双联齿轮与轴之间为空套联接，双联齿轮所在的轴段只受弯矩，不受扭矩；也就是说，输入轴只有靠近电动机一端的20mm长度上受扭矩，输出轴只是在靠近外伸输出端与其键联接的齿轮和外伸端部之间承受扭矩，因此轴的扭转刚度高。

III Investigations of ferromagnetic alloy films by XMCD1. By using XMCD and SQUID magnetometry, the spin and orbital moments of Fe and Co in the Co_(0.9)Fe_(0.1)(50nm) are studied. Compared with single-element film, the spin moment of Co remains constant while that of Fe reduced from 1.98 to 1.63μB. The contributions of different elements in the film is, m_ : m_ - 10.5 : 89.5. The average magnetic moment (1.90μB) determined by XMCD is in agreement with that (1.82μB) obtained from SQUID measurements. Utilizing XMCD spectra in-plane element-dependent magnetic anisotropy in Co_(0.9)Fe_(0.1) films has been investigated. Apart from known field-induced easy axis during film growth, a soft axis perpendicular to it was observed, and hard axes are 66° away from the easy axis.

利用XMCD谱研究了50nm Co_(0.9)Fe_(0.1)薄膜，结果发现：样品中Fe、Co元素对磁化强度的贡献比为10.5∶89.5；由XMCD获得的合金平均原子磁矩1.90μ_B与用SQUID磁强计得到的合金平均原子磁矩1.82μ_B基本相符；对Co_(0.9)Fe_(0.1)薄膜面内元素分辨的磁各向异性的研究发现，除了在生长的磁诱导方向存在易磁化轴外，与该轴垂直的方向还存在一个类似易轴的软磁化轴；面内的两个难磁化轴与易磁化轴取向大约成66°夹角，构成面内双轴磁各向异性，并根据XMCD结果对面内双轴形成的原因进行了分(来源：Ad2BC82论文网www.abclunwen.com)析。2。

Our patients were seen to have higher rate of feet postaxial polydactyly both clinically and radiologically; they had lower rate of clinical postaxial polydactyly over hands, with feet preaxial polydactyly both clinically and radiologically compared to previous review articles covering 52 cases.

临床上，与文献上收集52例比较不管是外观或放射线检查上皆有较高比例的足部中轴后多趾；较低比例的手部中轴后多指及足部中轴前多趾之现象。

To improve the investment environment, SED designs a city central axis landscape belt which will become the green hinge of Chengyang District, combining the functions of culture, business, living and tourism. Sea culture theme--modern development--natural ecology will be the main melody of the central landscape axis. The civic square, commercial area and residential communities are designed to imply the significancy of "openness, creativity, and harmony" respectively.

为更加完善的投资环境， SED新西林景观国际设计了城阳区城市中轴景观带，在设计规划中，未来的中轴景观带将成为城阳区文化、商业、旅游、居住的绿色枢纽；海文化主题--现代发展--自然生态，成为中轴景观主旋律。

Child growth and development in the eye, the eye grew from a small, axial length gradually increase, if the eyeball as a sphere, it has three axes, namely, longitudinal, transverse, sagittal axis, a sphere is the length of the three-axis equivalent.

儿童的眼睛在生长发育中，眼球由小长大，眼轴逐渐增长，如果将眼球看成一个球体，它有三个轴，即纵轴、横轴、矢状轴，一个正球体的三个轴的长度相等。

In this paper, several methods are put forward, by which axial resolution of scan microscope could be improved. One is that detecting method of ordinary laser feedback is improved, the orthogonal polarized lights split by Wollaston prism are detected separately, comparing to the ordinary feedback, the axial resolution is improved about 2.9 times.

提出并实验研究了几种可以提高激光反馈扫描显微镜轴向分辨率的方法，一种方法是对常规激光反馈实验中的探测技术进行了改进，用渥拉斯顿棱镜把垂直偏振光分开探测，轴向分辨率可以提高约 2 9倍；另一种方法是用双频激光器中产生的偏振态相互垂直的o光和e光作为反馈光代替了传统的单一光的反馈，轴向分辨率被提高了约 2倍；第三种方法是用双频激光器中产生的o光或e光作为反馈光，轴向分辨率可以提高约 2 5倍。

Therefore, for improving the accuracy of exceed slender axle on turning,must need to do with the lathe fixture and cutting tool for further improvement. In order to reached the requirements of precision machining,in machining process must use follower rest、flexible active thimble、space block and bracket etc fixture and assistive device.

超细长轴在车削加工中承受自身重力、切削力、高速旋转产生的离心力的作用，极容易出现振动与弯曲变形现象，增大轴的几何形状误差，而超细长轴的轴向尺寸较大，直径较小，热扩散性及刚性差，受切削热作用会在轴向发生线性膨胀，若在轴向的伸长量无法得到消除，轴将受迫弯曲，从而影响轴的精度。

By implementing immersion lithography, Matsushita/Panasonic has achieved the smallest minimum metal patterning that we have seen to date, at 67-nm M4 half-pitch.

由于使用了浸入式光刻，松下实现了至今为止最小的金属布线，第四金属层半节距为67nm（两条布线中轴的距离为节距，按布线宽与隔离空间各一半算的话，布线的实际宽度为半节距）。

The distance from focus of linear accelerator to middle abdomen of patients was 600cm.

我们使用从加速器射源焦点到病患中轴的距离为600cm的技术。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。