查询词典 keep the change

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。

All right, here is the money. You can keep the change.

好的，这是邮费，找的钱你留着吧。

Here's the 1100 yuan, keep the change.

这是1100元，不用找了。

Here is ten yuan and keep the change.

这是找给你的十元钱。

Keep the change, it's neither here nor there.

你拿着找的钱，这无关紧要。

Pearl S.Buck's translation of Shui Hu Chuan adopts the foreignizing or defamiliarizing method to keep the foreign flavor so that the target readers can keep having new findings and that the target text can increase its readers' aesthetic happiness and change the familiar in their perce...

赛珍珠的《水浒传》英译本采用了能够保留异国情调的异化或"陌生化"翻译手段，从而使译入语读者不断有新的发现；或者说译本通过延长审美时间和增加感觉难度而增强了读者的审美快感，并最终使其在观察世界的原初感受中化习见为新奇。

It is well known that the vocabulary of English word is very large, so if learners just recite every word independently, they cannot keep their memory long. In order to keep the memory of word effectively and firmly, one should grasp the basic word-building elements, and then recite the word systemically and relationally according to its relationship with other words and its own pronunciation, form and meaning. It is also necessary to grasp the rule of the words' change and transform in every aspects, turn rote reciting into comprehension reciting, singleness reciting into colony reciting, stiffness reciting into agility reciting.

英语词汇数量之多是众所周知的，而彼此孤立的词是难保持长期记忆的，所以要更有效地、更牢固地记忆单词，只有抓住其基本构词成分，根据每个词的音，形，义及其与其他词之间的诸多联系进行有系统地、有联系地记忆，掌握英语词汇在各方面变化和转化的规律，化机械记忆为理解记忆，化单个记忆为群体记忆，化呆板记忆为灵活记忆。

Ford was very kind – he gave the barman another five-pound note and told him to keep the change.

福特确实是一个好心人——他给了老板另外一张5英镑的钞票然后告诉他不用找了。

Change is inevitable, but if you take a bird's-eye-view of the landscape, the change won't be so disorientating and you will keep perspective at all times.

变化是不可避免的，但是如果你鸟瞰景色，变化则不会如此迷茫，你也可以随时保持判断。

None Other Than a Soldier Best Reward Skunk A Mistake Good News And Bad News Perfect Match Patience The World's Greatest Swordsman Only Once Starstruck Keep the Change Persistance Treat Imitation Bedtime Prayers I'm Glad I Taught the Teacher A Baby Sister Lucky Mother A Problem in Arithmetic Things Have Been Okay That's Why Millionaire A Trip to Disney A Family Rule An Old Couple's Quarrel Twin Lobsters A Fine Match The Same Service I Don't Know Her Class and Ass Plagiarism Virtue Difference Flunking Math Part-time Job Keys?

其余的事由我负责热与冷士兵的高招新发现一个坏印象⊙工作插曲安眠药创造性催单模仿鸟儿你是怎样来的？

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。