分布参数

In this paper, the JFO condition, satisfied with global mass continuity, is incorporated into an universal Reynolds equation with micro-polar fluid which is solved for the oil film pressure using OSM and FEM. The bearing load capacity and friction resistance were given, and stiffness/damping coefficients and critical rotor mass were obtained by solving a pressure perturbation equation with micro-polar lubricants.

本文采用满足全流场质量连续的JFO边界条件，采用微极性流体的广义雷诺方程来求解油膜压力分布，进而获得油膜承载力和粘性阻力等轴承动力特性量；采用小参数摄动法得出油膜压强扰动方程，并采用有限元法解出扰动压强，积分扰动压强获得油膜的阻尼系数和刚度系数，进而求得了表示轴承油膜稳定性的临界转子质量。

Through contrast and analysis of two sets of designed parameters, the result shows that optimizing method can obtain more satisfying effect in the hand of narrow azimuth seismic survey and equilibrium distribution of inline and crossline coverage.

应用该设计方法对胜利探区4个实际区块的观测系统参数进行了优化设计和对比分析，结果表明，在窄方位角采集，纵横向覆盖次数均匀分布等方面该方法的效果较好。

119 4 And 0. 006 7, respectively. Both the failure probability density function and the cumulative distribution function can be presented by this degradation failure model.

所选的某型金属化膜脉冲电容器未知参数估计值为0.0001194和0.0067，将该值代入失效分布函数和概率密度函数中。

The current sensitivity probability density function of energetic materials was deduced based on Frank-Kamenetskii parameter and resistance supposing as stochastic variable of normal distribution, by the application of the probability density formula of function in two random variables.

将Frank-Kamenetskii参数和电阻假设为正态分布的随机变量，应用二维随机变量函数的概率密度公式，推导出了含能材料电流点火感度的概率密度函数。

According to the connective equation of normal distribution function of these parameters, the paper proposes a simple and practical method for the reliability design of involute cylindric gear transmission, and derives a design formula and a proofread formula.

根据这些参数的正态分布函数的联接方程，提出了渐开线圆柱齿轮传动可靠性设计的一种简单适用的方法，并推导出了设计公式和校核公式。

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。

Non-parametric estimations reveal that the fat tail of the distribution of stock return satisfies power law decay.

非参数估计显示股票收益分布的非正态性及"肥尾"现象，其尾部满足幂律衰减。

The character and distribution rule of CC round billet internal defect are analyzed and the relation between the defect and process parameters are found, which provide the reference for the billet quality improvement.

本文分析了包钢连铸圆坯内部缺陷的特征及分布规律，找出了内部缺陷与生产工艺参数之间的关系，为改善圆坯质量提供了依

Using finite difference time domain method, the electromagnetic field distribution of THz wave is simulated in a THz 2D PC splitter and by plane wave expansion method the dispersion relation and defect modes are achieved in a THz rotated PC waveguide.5. A woodpile three-dimensional (3D) PC with face-centered-tetragonal symmetry is one of the most popular 3D PCs because of its favorable band gap characteristics. Based on the woodpile fct lattice structure, we propose a novel woodpile THz lattice structure with comparatively decreased symmetry, better band gap properties and easy fabrication by varying some structure parameters.

计算结果为利用非线性光学差频方法产生THz辐射源的实验研究提供了深入和全面的理论基础；四、利用平面波展开法，通过改变二维THz光子晶体的结构参数，对二维THz光子晶体完全带隙进行了优化，分析出两种适合工作在THz波段的二维光子晶体结构；采用时域有限差分法和平面波展开法，计算出THz波在二维光子晶体"T"型分束波导，45度旋转波导中传输的电磁场分布以及缺陷模；五、Woodpile面心立方四角结构是三维光子晶体中被研究最广泛的结构之一。

The co-Kriging method considering the altitude influences is applied to get the rainfall in grid elements. The vegetal cover and landuse conditions in regions of interest are acquired from remote sensing data. The function relationship between the maximum of soil moisture deficiency and topography index is given. The flow concentration paths of net rainfall in every grid element are gotten from DEM, which solve the problems of rainfall input and parameters grided.

利用考虑高程影响的协克里金方法确定单元网格时段降雨量；利用遥感资料获取研究区域内的植被覆盖情况、土地利用分布情况等；建立了最大缺水量同地形指数之间的函数关系，基于数字高程模型确定单元网格中净雨的汇流路径，从而解决了模型产汇流计算过程中的降雨输入和参数网格化问题。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。