成对比的

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 will promote to the airline company improving services and enhance level of management and benefit of operation. This will advances the development of national economic and meet the requirement of people life and business activity, and increase the living quantity, and adapt to the travel industry to make use of. Everyone in the civil aviation should pay attention to.This paper analyzes the problem of development of regional aviation transport from three angles. Combining with the background of our country social economy development, and the speeding and improving service and advancing the marketing means, the compete power of three main transportation modes of regional aviation and railroad and highway in our country. From angle of tripper, a mathematical model of trip cost is established to quantitatively describe the choice behavior of passengers to select the model transportation. A

结合我国社会经济发展的背景，以及地面铁路和公路不但提速、改进服务和营销手段的现状，首先定性的分析了我国目前主要的三种客运方式支线航空运输、公路运输和铁路运输的竞争能力，然后从旅行者的角度，使用旅客出行成本模型，对成渝线、福厦线和台高线航线上不同出行方式的出行成本进行了对比研究，提出降低旅行成本，增强支线航空运输竞争能力的建议和方法；接着提出了利用层次分析法和模糊评判理论，对目前国内所采用的支线机型进行分析比较的方法，建立了选择支线机型的方法和评判标准，这给航空公司在发展支线航空选择机型时提供了一种评价选择方式；然后应用博弈论的方法、模型，分析支线航空运输航线结构变动时各种运输方式的经济行为、成因、结果及合理措施，提出航空公司发展支线航空运输的对策；最后对我国支线航空运输的现状进行了分析，并对未来支线航空运输的发展进行了预测，有针对性地提出了我国支线航空运输的发展策略。

Focusing on the PGE enrichment mechanism in the basic-ultrabasic intrusions in the Panxi rift, firstly, through the interpretation of TM photograph, data processing of regional geochemical exploration and geophysical prospecting results of gravity, magnetic force and seism, we analyzed the controlling effect of structure and magmatic movement on the PGE mineralization; Secondly, through the study of volcanic apparatus, petrography, measurement of comprehensive geochemical section, isotope tracing and dating of typical PGE-rich melanocratic rock series, we discussed the sources of the PGE-bearing mafic-ultramafic intrusions and basalts, their timing, evolvement sequences, the geochemical processes of magma crystallization and fractionation, and the relationship between magma evolution and structural development; Finally, through the analysis of PGE and chalcophile elements concentrations in the melanocratic rock series and the contrastive study with the Noril''sk magmatic Ni-Cu-PGE sulfide deposit, its related continental flood basalts and Siberia Traps, we discussed PGE mineralization characteristics and its enrichment mechanisms in the melanocratic rock series in the Panxi rift.

本项目首先围绕川西地区主要的PGE矿床及伴生矿的地质环境和有关的地质构造背景，通过TM卫片解译、区域化探和重、磁及地震物探资料分析，总体把握构造及岩浆活动对PGE成矿的控制作用；然后通过对典型富PGE暗色岩套的火山机构地质构造、岩石岩相学、地球化学、同位素定年和示踪等方面的工作，分析本区基性－超基性含矿岩体与喷出岩之间的成岩物质来源、侵入时代及演化序列，研究该区同一岩浆房分异结晶的地球化学过程及其随构造发展的耦合关系；最后通过对暗色岩套PGE地球化学剖面分析以及与俄罗斯诺里尔斯克陆内裂谷溢流型玄武岩中PGE矿化的岩石－构造环境对比研究，探讨该区暗色岩套中的矿化特点和富集部位及其PGE富集机制。

Objective: This experimental study is based on earlier animal and clinical experiment, drawn thinkings of combinations with two methods and pursued a synthesis method of high-efficiency, cheap and convenient calcium and exercise treatment. We adopt taking natural-clam's casing powder and preconcereted-intensity excises to intervene shape of osteoporosis in gelded rats, than we compare the indexes such as the biomechanics indexes of the right femur and the third lumbar vertebrae, the weight and uterus quotiety of rats before the experiment to these indexes after the experiment. We hope to find better and suitable way to prevent and treat the postmenopausal osteoporosis and offer reference for clinic.

目的 本实验的主要目的是在前期动物实验的基础上，引入两种方式联合干预的思维，立足于探求既高效又经济、方便的补钙剂加上与运动疗法相联合的方式，对切除雌性大鼠卵巢而复制成的骨质疏松症模型进行服用天然贝类蛤蜊壳粉，同时施以预定强度的运动刺激的方法，再通过试验前后大鼠体重、子宫指数的变化及大鼠股骨和椎体生物力学指标的对比变化进行分析，以期探索出防治绝经后骨质疏松症的更好的、更适宜于大众的手段；并为天然钙剂和运动联合作用防治PMOP提供参考。

Results: l、The optimal scan parameters for chinese people are flow rate of 3. 0 mL/sec and total injection 125ml. 2、Visibility of coronary arteries and segments: only those proximal and mid segment is image quality sufficient to allow a semiquantitative assessment. 3、Detection of Atherosclerotic Plaque: CT coronary imaging revealed highest sensitivities for the detection of atherosclerotic wall changes the sensitivity of stenoses was 86. 3％. 4、MSCT coronary angiography is easy to prove the entire anatomic structure of coronary and it is an effective technique for evaluating coronary patency. 5、MSCT coronary angiography correctly identified all normal controls and all patients with coronary artery fistula. The anatomic course of the coronary artery fistula was correctly classified. 6、A11 severe lesion could be visualised by

结果：1、不同的扫描技术参数所获得的造影图像质量不同，注射速率3.0ml/s组以及125m1对比剂总量组比较适合国内患者。2、多层螺旋CT冠状动脉造影可显示冠状动脉的主要分支，尤其是冠状动脉的近、中段，显示率在90％以上。3、多层螺旋CT冠状动脉造影对狭窄病变的敏感性为87.3％，能检出冠状动脉造影不易发现的细小斑块，判断狭窄的原因及斑块的特征。4、多层螺旋CT冠状动脉造影可显示搭桥血管的形态、位置及通畅程度，显示桥血管及支架的内腔，安全便捷。5、多层螺旋CT显示冠状动脉畸形准确性高（3/3），多种成像方法可弥补冠状动脉造影显示的不足。6、仿真内窥镜可显示冠状动脉内膜和内腔，显示狭窄斑块的性质。

The reason included five aspects:①the effect of physical environment: the open geographical environment and barren soil urge the Greeks to look for development outward while the close geographical environment and advantaged condition for agriculture shaped the Chinese conservative thought and obstructed their steps of going out.②the advancing and blocking of the economic: the frequent trade offered an abundant living supply and open view while the self-sufficient agriculture with restraining trade rigidified the thought.③ the difference in politic institute and situation: the democracy polis of ancient Greece is exclusive in the ancient world. It shaped the atmosphere of freedom, democracy and adversary. While the monarchy in ancient China pursued the "united country" and shaped the atmosphere serving for politic and consolidating thoughts.④the guiding of traditional culture: the Greeks pursued freedom and wisdom and were curious about nature while the Chinese adored ancestor and obeyed the authority and prefer to pragmatism.

出现这种关系的原因本文从以下五点进行分析：①自然环境的影响：古希腊开放的地理环境和贫瘠的土壤种植条件促使古希腊人向外寻求发展，而古代中国封闭的地理环境和优越的农业环境阻碍了中华民族外出的脚步和开放的思维；②经济条件的推动与束缚：工商业发展的农业经济和自给自足的小农经济所创造的物质条件和对思维影响的差别是很大的；③政治制度和政治形势的差异：古希腊民主城邦制在古代世界是独树一帜的，它所营造的自由、民主的氛围和古代中国追求&大一统&的君主专制下为政治服务、思想趋向统一的氛围截然不同；④传统文化的引导：古希腊人在长期的城邦生活和参与海外贸易的生活中形成的开放、自由、对自然充满好奇、追求智慧等民族文化传统与中国保守崇古、讲究实用的文化传统形成了鲜明的对比；⑤思想家本身(来源：A58BC论文网www.abclunwen.com)目的不同：古希腊思想家为了变得智慧而获取知识，享受知识带来的乐趣，而古代中国思想家的一切动机都是为了&成化天下&、&以政裕民&服务。

The reason included five aspects:①the effect of physical environment: the open geographical environment and barren soil urge the Greeks to look for development outward while the close geographical environment and advantaged condition for agriculture shaped the Chinese conservative thought and obstructed their steps of going out.②the advancing and blocking of the economic: the frequent trade offered an abundant living supply and open view while the self-sufficient agriculture with restraining trade rigidified the thought.③ the difference in politic institute and situation: the democracy polis of ancient Greece is exclusive in the ancient world. It shaped the atmosphere of freedom, democracy and adversary. While the monarchy in ancient China pursued the "united country" and shaped the atmosphere serving for politic and consolidating thoughts.④the guiding of traditional culture: the Greeks pursued freedom and wisdom and were curious about nature while the Chinese adored ancestor and obeyed the authority and prefer to pragmatism.

出现这种关系的原因本文从以下五点进行分析：①自然环境的影响：古希腊开放的地理环境和贫瘠的土壤种植条件促使古希腊人向外寻求发展，而古代中国封闭的地理环境和优越的农业环境阻碍了中华民族外出的脚步和开放的思维；②经济条件的推动与束缚：工商业发展的农业经济和自给自足的小农经济所创造的物质条件和对思维影响的差别是很大的；③政治制度和政治形势的差异：古希腊民主城邦制在古代世界是独树一帜的，它所营造的自由、民主的氛围和古代中国追求&大一统&的君主专制下为政治服务、思想趋向统一的氛围截然不同；④传统文化的引导：古希腊人在长期的城邦生活和参与海外贸易的生活中形成的开放、自由、对自然充满好奇、追求智慧等民族文化传统与中国保守崇古、讲究实用的文化传统形成了鲜明的对比；⑤思想家本身目的不同：古希腊思想家为了变得智慧而获取知识，享受知识带来的乐趣，而古代中国思想家的一切动机都是为了&成化天下&、&以政裕民&服务。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。