专门技术

"Cyberterminology" the subject of the authors study in this thesis, is a general reference to all the special words and expressions used in computer network technology and those used in cyberculture and cybercommunication.

本文的研究对象"网络词语"是指计算机网络技术专门词语、网络文化词语及网络交际所使用的词语总和。

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。

In 1962, Peter Drucker, the famous master of economics and management, presents definitely that logistics was the last area for decreasing cost in his paper Economy"s Dark Continent published in fortune. For 40 years, the concept of logistics was expanded continually and more and more attentions were paid on it. Especially from middle of 1980"s to this day, with the increase of economic globalization and development of the information technology, more and more enterprises go back to their main businesses, and pay their points on these businesses such as product development, manufacture, marketing, which are their core businesses and they are good at. These businesses embody the competitive advantages of the enterprises.

1962年著名经济管理学大师彼得·杜拉克在美国《财富》杂志上发表《经济的黑暗大陆》一文，首次明确地提出物流是节约成本的最后领域。40年来，物流的概念在不断地拓展，人们对物流管理越来越重视，特别是80年代中期至今，随着经济全球化竞争的加剧、信息技术的飞速发展，许多生产企业回归主业，将精力集中于产品开发、生产、销售等具有竞争优势的核心专长业务的呼声日益高涨，理论界和企业界已不再浅层次的探讨物流管理的重要性问题了，他们开始探讨物流管理的模式问题，即：究竟是自营物流业务，还是将物流业务外包给专门从事物流管理的企业去做。

As a technological company integrating scientific research, production and sale, it specializes in the research and development of deoxidizer and the technology of storage by deoxidizing and sealing.

是集科研、生产、销售为一体的专门从事除氧剂与除氧封存技术研发的科技公司。

Finally a all-digital recorder system based on RAID5 which has a RT-Linux real-time software operation system and intermediate/video frequency acquisition card driver to overcome such problems as real-time quality reliability chunnel expansibility and standardization.

最终提出了以RT-Linux实时操作系统为软件平台和专门设计的中频和视频采集卡驱动为底层硬件平台的基于RAID5阵列的全数字记录系统，全面解决了记录实时性、可靠性以及通道扩展性和标准化的技术难题。

GARETH MITCHELL: Now that Joe Selanikio who is cool founder of "Data Dyne", which is a non-profit company that assist governments and NGAs with information technology.

加雷思·米切尔：现在乔·瑟拉尼克欧创办了"数据达因"，这是一家非营利性质的公司，专门协助政府和NGA解决信息技术问题。

Eastbound Shanghai Institute is the process research and development center for Eastbound group of companies.

上海展昱生化科技有限公司，是Eastbound 集团下属的专门从事工艺研究和开发的技术中心。

This programme is designed for those who want to know how information technology can en...

这一方案是专门为那些谁想知道的信息技术可以提高他们的决策，以及日常运作。

Here we exchange programming algorithm for ideas, etc.

这里专门给大家交流编程算法，思路等技术。

Welcoming Sir Ka-shing Li's donation, Professor Farrar said it was an incredibly exciting development for clinical research and education in international health.

牛津大学的全球卫生科学系理学硕士课程专门为研究生和在职专家，提供有关热带传染病、流行病学、公共卫生，以及卫生经济等范畴的知识和技术。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。