查询词典 amplitudes

Variances were found among the varying amplitudes of the individual ecological field gradients of Alsophila spinulosa in different sites. The maximal gradient values and effect distances of the maximal gradients also varied.

不同地段的桫椤种群个体场梯度大小变化幅度不同，最大场梯度值以及出现最大场梯度时的作用距离亦不相同。

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。

The experiment used methods of sport biomechanics to investigate the electromyographic magnitude of eccentric and concentric phases under two different stretch amplitudes of drop jumps in order to understand neuromusculor characteristics of different stretch amplitudes of SSC movement.

本研究是利用运动生物力学的方法，探讨肌肉牵张缩短循环（stretch-shortening-cycle SSC）的典型动作drop jump 20、40和60cm之肌肉工作特徵，以便了解浅蹲和深蹲法的DJ跳法之离心和向心收缩二阶段的肌电活动特徵。

Formant amplitudes are produced from input cross-section amplitudes at estimated formant frequencies.

共振峰幅度是由在估计的共振峰频率上的输入截面幅度产生的。

On the other hand, in terms of the above,"superposition principle of probability amplitudes" in quantum mechanics ought to be indicated as "probability amplitudes is independent of passage conditions."

另一方面，按照上面的用语，量子力学中的"概率幅的迭加原理"应表成"概率幅不依赖于通道条件"。

As a whole the effective assess ment index of intraoperational monitor had been established, providing reference for the lumbar spondylolisthesis surgery.Taking the SEP index value of postanesthetic patients before operation as the standard, the changes of intraoperational potential may indicate the following status: The latency period decreasing in 10%-15% or the amplitudes increasing in 40% indicated that the outlook of recovery was good enough and the prognosis was favoured.The latency period decreasing in less than 10% or the amplitudes increasing in less than 30% indicated that part of the function could be reduced.

以患者术前以及麻醉后的SEP指标值为基础，术中监测电位指标变化表现形式：①滑脱复位后，若潜伏期缩短10％～15％或波幅增加＞40％，提示预后良好；②监测电位指标平稳，或潜伏期缩短＜10％，或波幅增加＜30％，可继续完成复位，术后可有部分功能恢复和症状改善；③在复位过程中，监测电位指标出现暂时性波动，可在15～20min内恢复到基础电位，应在电位出现波动时停止复位，术后仍可恢复部分功能和改善症状。

Under different forestry work conditions,the EMG amplitudes of Erector spinae were not at the same level in the process of forestry operating,although the average intensity of Erector spinae was probably identical under different forestry work conditions,the EMG amplitudes of Erector spinae distribute in different ranges of MVE%,and the duration spent in the certain ranges of MVE%is not same in the process of entire operating.

在不同作业工况下背部竖脊肌在整个操作过程中工作强度不尽相同，虽然在不同的作业工况下背部竖脊肌平均工作强度可能相近，但是在整个操作过程中，肌肉的用力程度是处于不同MVE%范围内的，且在整个操作过程中肌肉在不同的MVE%范围内所持续时间不同。

The thesis analyzed the influence of terrains and chain saws on the trunk muscles.The results showed that the terrains only influenced the Erector spinae amplitudes(p＜0.05),while it makes no sense to study the the influence of terrains on other muscles amplitudes.

在对不同地势与不同油锯对躯干各肌肉活动影响进行分析时发现，不同地势只对背部竖脊肌肌肉活动有影响(p＜0.05)，而对其他肌肉活动影响无统计学意义。

In the protanopes,the shorter latencies of N1 ,P1,N2 and greater amplitudes of N1-P1,P1-N2 appeared in 520~530nm and 570nm,forming the two-thoughs and two-peaks shapes,with the shortest latencies and the greatest amplitudes in 520~530nm.

先天性红色盲则分别在520~530nm和570nm处潜伏期较短而振幅较大，形成双谷样和双峰样改变；最短潜伏期和最大振幅位地520~530nm处。

Results No statistical differences of amplitudes and latencies of the maximal electrical twitch of femoral nerve were found between involved and uninvolved limbs,but the amplitudes of quantitative patella tendon reflex of involved limbs were statistically lower than those of uninvolved limbs.

结果：健侧与患侧相比，膝OA的股神经最大电刺激的肌电波幅与潜伏期无显著差别，但患侧定量髌腱反射肌电波幅却显著地低于健侧。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。