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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。

This paper studies the resources allocation in multi-project based on the analysis of relevant articles from home and abroad. This paper focuses on organization structure and resource optimization allocation based on the quantity of resource allocation on an activity as decision variable.

本文面向多项目管理中的资源优化配置问题，针对现有优化方法存在的不足，从组织结构和资源受限条件下资源作为决策变量的多项目资源优化配置方法两方面展开研究。

There are four categoriesabout the method of magnetic field : base on law of electromagnetic induction, the methods of measurement based on mechanical, base on magnetic field effect, based on the magnetic resonance method.

磁场测量的方法主要有四类：基于电磁感应定律的方法，基于力学测量的方法，基于磁场电效应的方法，基于磁共振的方法。

This thesis is based on Becker's subjective expected utility theory. This thesis analyses crimes by economic perspectives and from criminals' viewpoint regarding cost and benefit. Besides, based on crime deterrence theory, this thesis applies crime examples to deliberate on social, economic and political variables' influence on crime rates of grand total crime, larceny and violent crime.

中文摘要本文主要系以Becker的主观预期效用理论为基础架构，尝试以经济学的观点来分析犯罪行为，从犯罪者的角度，考虑其犯罪成本与利益，再根据犯罪吓阻理论，以实证来探讨社会、经济及政治因素的变动对全般刑案、窃盗及暴力等三种类型犯罪发生率的影响。

This paper analyze and study the influence of the superimposition in depth based on the previous achievements and combined with the theoretical qualitative analysis and project instances. The main contents as follow:Chapter 1: Indicate the significance and objective of this paper, review the previous achievements of the transient process and superimposition, and then present the study purpose of this paper.Chapter 2: combined with the physic knowledge of the fluctuation and the superimposition, Indicate the physical essences and the influence of the superimposition phenomena that exist in the diversion pipe system, and take one hydraulic turbine owning only one diversion tunnel and two hydraulic turbines sharing one tailrace conduit for instance to study out the numerical calculation superimpose operations.Chapter 3: From the calculation theory of the parameter of the guaranty calculation of regulation of the hydro-turbine, qualitative analyze the influence of the superimposition on them and the superpose time, combined with some project instances, get the numerical value of the influence of the superimposition and the superpose time.Chapter 4: Based on the previous achievements of the calculation and theoretical analysis of the surge-chamber ground swell, analyze the influence of the superimposition on it and the superpose time.

本文在前人研究成果的基础上，结合理论定性分析及工程实例，对波动叠加带来的影响进行深入分析研究，其主要内容如下：第1章，指出本文研究的意义和目的，回顾前人对水电站过渡过程及波动叠加方面的有关研究成果，在此基础上提出本文的研究内容；第2章，结合物理学中有关振动与波动叠加方面的有关知识，阐述水电站引水发电系统中存在的波动现象的实质及其影响，并以两机一洞和一机一洞具有上游调压室或下游调压室的水电站拟定其数值计算叠加工况；第3章，从机组调保参数的理论出发，定性的分析波动叠加对机组调保参数的不利影响及叠加时间，结合几个工程实例，得到波动叠加带来的影响大小及叠加时间；第4章，在前人对调压室涌浪进行计算和理论分析的基础上，分析波动叠加对调压室涌浪的影响及其叠加时间。

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These descriptions are brief, but based on them it is indeterminable and has disadvantage in system design and direct implementation. On the other hand, these works mostly focus on describing variants behaviors of Ambient calculus in one level, which makes it complicated to understand clearly how these variants behaviors work and how they work together. As a result, based on the unit ambient of Ambient calculus, a three-level semantics description framework is given for Ambient calculus.

这种描述方式尽管简洁，一方面却具有不确定性，不利于实际的网络计算系统的设计和直接实现；另一方面，这种语义描述方式均在一个层次上描述Ambient演算系统中的各种行为语义，使得Ambient演算中各种计算行为纠缠在一起，复杂而难以理解。

Combining the experimental results and theoretical analysis, the following work has been accomplished.(1) Reasons of the decrease of interelectrode capacitance and the increase of discharge gap caused by the powder suspended in dielectric fluid are explained. And the mechanism that surface quality of workpiece improved by powder-mixed EDM is analyzed from this viewpoint.(2) The variation regularity of the percentage of silicon on the machined surface of workpiece has been summarized according to the experiment results when silicon powder was added into the working fluid. The entropy is introduced to explain the reasons for this variation regularity by thermodynamics.(3) The dimensional accuracy is greatly influenced by the overcut resulting from discharge gap and electrode wear in practice application. Empirical formulas for the overcut in EDM and powder-mixed EDM are established based on the experimental results using the ternary linear regressive method in this paper.(4) The influence of main factors on the machined surface characteristics has been evaluated based on the orthogonal experimental design method.

通过一系列普通电火花加工与混粉电火花加工的对比实验，运用工艺实验和理论分析相结合的方法，重点做了以下工作：(1)探讨了粉末颗粒导致极间电容减小、放电间隙增大的原因，并从这个角度解释了混粉电火花加工可以改善工件表面质量的机理；(2)以混合硅粉的电火花加工为例，实验得出峰值电流和脉冲宽度对加工表面层成分中硅元素含量的影响规律，并引入熵的概念从热力学的角度对硅元素含量变化的原因寻找了理论依据；(3)在实际加工中，由于粉末的加入使放电间隙变大，这使得混粉电火花加工的尺寸精度难以控制，本文利用三元线性回归的方法，在实验数据的基础上，建立了两种电火花加工过切量的计算公式；(4)将正交试验法应用于混粉电火花加工实验研究，并通过对实验指标极差的直观分析，得出各电参数对加工指标影响的敏感程度。

All enhancers did not significantly change the transcorneal lag time of ENX. The irritancy of poloxamer and Azone was observed.? The results of in vitro release studies showed that the ENX gel based 3% HPMC K4M and 3%HPMC F4M povided sustained release of the drug over an 8-h period in vitro.Diffusion area has significantly effect on drug release, and pH value of medium and rotation rate have effcet on drug release.However, the diffusion shield has no effect on drug release. The P_ value of the preparation based on 3% HPMC F4M was 1.34-fold of conventional eye drops of ENX.

体外溶出度试验结果表明，以3％的HPMC K4M和F4M为基质制备的ENX凝胶剂的体外释放行为符合眼用缓释制剂的要求；体外释放度影响因素试验结果表明，释放面积对释放度有显著性影响，pH值和转速略有影响，而扩散屏障没有影响；离体角膜透过实验结果表明，以F4M为基质制备的凝胶剂中ENX的表观渗透系数P_(app是对照组的1.34倍，说明F4M与眼角膜的相容性较好，是一种理想的眼用制剂增稠剂，可以在眼用制剂中广泛采用。

In this paper the definition of signcryption KEM is extended in ID-based cryptography. Based on Sakai-Kasahara identity-based key contracture and elliptic-curves-related hard problems, an instance scheme of ID-based signcryption key encapsulation is proposed. Security properties of the proposed scheme are proven with the random oracle model.

在基于身份密码体制上扩展了签密密钥封装的定义，结合Sakai-Kasahara私钥提取结构以及椭圆曲线上相关的困难问题给出了一个基于身份的签密密钥封装的实例方案，并在随机预言机模型下对该实例方案的安全性进行了证明。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。