小沟

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。

Saying to come to God uprear, wipe clean with the dress, move deferentially into temple, put on, did obeisance to next two do obeisance to ability to leave.

庙门前有一条小水沟，有个人走路来到沟前，过不去，四下看看，看见小庙，便进去把神像搬下来，横放在沟上，踩着走过去。

Base on the threshold voltage model presented, an intrinsic drain current model in strong inversion region is developed, which can describe the short-channel effects such as DIBL and charge-sharing effect well, and give special considerations for mobility, velocity saturation, channel length modulation and quantum effect. Based on the front interface surface potential model, a formula of unified inversion charge is derived, and an intrinsic drain current model in middle inversion region is developed.

利用所提出的深亚微米FD器件正、背界面表面势模型，建立了一个能够完整描述深亚微米FD器件本征亚阈漏电流特性的模型，能够准确地描述DIBL效应和背沟道漏电效应；利用所提出的阈值电压模型，建立了深亚微米全耗尽器件的本征强反型电流模型，很好地描述包括DIBL效应、电荷分配效应在内的小尺寸效应，对迁移率、速度饱和效应、沟道长度调制效应和量子效应进行了特别的考虑；利用所提出的深亚微米FD器件正界面表面势模型，推导了统一反型层电荷公式，建立了深亚微米FD器件的本征中反型漏电流模型。

In the Paper, through theoretical analysis of minimum allowance of that type bearing raceway , the determining method of raceway allowance is given.

本文通过对该类轴承沟道最小余量的理论分析，给出厂沟道余量的确定方法。

Ehrlichia chaffeensis 16S rRNA was amplified for the 1st time from Ixodes persulcatus and Dermacenter silvarum in China. The EC infection rate of 39.1 % in I. persulcatus and 10 % in D.

结果：从内蒙古莫尔道嘎林业局采集的全沟硬蜱和森林革蜱中扩增出查菲埃立克体的16S rRNA基因，阳性率分别是39.06%和10.00%；并从新疆精河采集的全沟硬蜱和草原革蜱中也测到相同的序列，最小阳性率分别为5.79%和1.67%。

But the value of H angle is smaller than class I malocclusion . Campared with the data of class II malocclusion , for class III malocclusion there are significant differences in LsL , LiL , lower lip angle of inclination , mentolabial sulcus angle , H angle , upper lower lip angle , Ns-Sn-Ls . For class III malocclusion the value of LsL is shoter than class II malocclusion , but the value of LiL is longer than class II malocclusion . The value of lower lip angle of inclination , mentolabial sulcus angle , upper lower lip angle is bigger than class II malocclusion .

安氏Ⅱ类错合患者与安氏Ⅲ类错合患者相比，在上唇长、下唇长、上唇倾角、下唇倾角、颏唇沟角、H角、上下唇角和软组织轮廓这些指标有显著性差异；安氏Ⅱ类错合患者的上唇长比安氏Ⅲ类错合患者的长、安氏Ⅱ类错合患者的下唇长比安氏Ⅲ类错合患者的短；安氏Ⅱ类错合患者的上唇倾角和H角比安氏Ⅲ类错合患者的大，安氏Ⅱ类错合患者的下唇倾角、颏唇沟角和上下唇角比安氏Ⅲ类错合患者的小。

Based on the result of field artificial rainfall experiments on 60m length slopes,sedi-ment delivery is consisted of raindrop impact,slope runoff and rill flow delivery.Accord-ing to their functions,rill was ranked firstly then slope run off,and last raindrop impact.

通过野外60m坡面人工降雨实验及过程结果分析可知：输移由雨滴击溅、坡面径流和细沟输移三部分组成，按作用大小来排，细沟流占第一位，坡面径流占第二位，雨滴击溅最小。

Methods 30 cases of nasal soft tissue de fects were reconstructed by different kinds of local flaps according to modified Burget′s nasal subunit. The Rintala flaps were used above the lowest level of low eyelids; at the area between low eyelids and the alar groove, the dorsal def ects were covered by ax-like local flaps and defects on side wall were reconstru cted by flaps rotated from the contralateral wall covered by skin graft; when it was below the highest level of alar groove, nasolabial flaps with subdermal ped ical were applied to nasal tip defection, and nasolabial local flaps to alar def ects, axial nasodorsum flaps supplied by the lateral nasal artery to defects inv olving columellae.

结合Burget鼻部美学分区，将其再分为三个区域，根据分区选用局部或邻位皮瓣修复鼻部各区软组织缺损30例(鼻根部以Rintala鼻额部局部皮瓣推进3例；鼻中段的鼻背部行双侧斧状局部皮瓣旋转3例；鼻侧壁行对侧壁局部皮瓣转移，供区植皮4例；鼻端部以鼻唇沟皮下蒂岛状瓣转移修复鼻尖部7例；鼻唇沟局部皮瓣旋转修复鼻翼部7例；鼻背轴型皮瓣旋转修复鼻小柱6例)。

Large amount of geological material was studied with statistics and geomechanics method,and the distribution law of factures in Cuijiagou mine has been found out:the main fracture s are along NNE and SN directions,other small fractures are controlled by the main fracture s.

利用统计分析、相关因素、地质力学分析方法对崔家沟井生产中积累的大量实际地质资料进行分析研究，找出了崔家沟井田范围内断层发育展布的规律，即近SN向及NNE向断层是本区的主干断层，共它小断层为其派生产物，小断层的展布受主干断层的控制。

Chestnut soil in an elevation of 2200-2800 meters ditch horse business, Jackdaws small ditch on the south side of the fire northwest of Chung Ling, Donggou, Zhang Bailu, XIAOLIUGOU, West Osaka Liang, Yan Hua stockade on the south side, the north slope of the Qilian Alluvial fan, a total of 202.56 million.

栗钙土 分布在海拔2200-2800米处的马营沟、小寒鸦沟南侧、火松岭西北侧、东沟、白露掌、大柳沟、西大坂梁、严家花寨子南侧、祁连北坡冲积扇上，共202.56万亩。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。