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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。

DPR of Atriplex canescens in differenttreatments are quite different, 2.87μmolm~(-2)s~(-1) under no soil water stress, 6.46μmolm~(-2)s~(-1) under light soil water stress, 6.06μmolm~(-2)s~(-1) under medium soil waterstress, 3.04μmolm~(-2)s~(-1) under heavy soil water stress. Comparing with the DPRunder light soil water stress, DPR decreased by 6.19% under medium soil waterstress, by 52.94% under heavy soil water stress and by 55.57% under no soil waterstress.

不同土壤水分胁迫下四翅滨藜的DRR表现出显著的差异，无土壤水分胁迫下DRR为2.87μmolm~(-2)s~(-1)，轻度土壤水分胁迫的DRR为6.46μmolm~(-2)s~(-1)，中度土壤水分胁迫的DRR为6.06μmolm~(-2)s~(-1)，重度土壤水分胁迫的DRR为3.04μmolm~(-2)s~(-1)，以轻度土壤水分胁迫为基础中度土壤水分胁迫下降了6.19％、重度土壤水分胁迫下降了52.94％、无土壤水分胁迫下降了55.57％。

As to'Cabemet Sauvignon'and'Queen of Vineyard', which belong to the'West Europe Cultivars Group', no obvious decline of Fv/Fm was found in their potted plants even under severe drought stress. Their photosynthetic abilities also greatly recovered after rewatering, i. e. no serious photodamage was formed in these cultivars under drought stress. Between them, the φPSⅡ of 'Queen of Vineyard'under severe drought stress was much lower than that of'Cabernet Sauvignon', which suggested that the light use efficiency of the former was much lower than the latter under severe drought stress. The potted plants of'Autumn Royal'and'Rizamat' sustained high Fv/Fm and φPSⅡ before moderate drought stress, but seriously declined under severe drought stress, which indicated that these cultivars had a weak resistant ability to extreme drought stress. A hybridized cultivar of Vitis vinifera L. and V. labrusca L.,'Red Double Taste', its Fv/Fm and φPSⅡ expressed mild decline along drought stress grade.φPSⅡ of'Red Double Taste'was the highest among seven cultivars under severe drought stress condition, which might closely connected with its high photorespiration activity. Another new cultivar,'Red Globe', and a rootstock,'1103Paulsen', the Fv/Fm and φPSⅡ of their potted plants declined markedly under slight drought stress, which suggested that they held a weak ability to defend against photoinhibition.

西欧品种群的赤霞珠和葡萄园皇后，其盆栽苗的Fv／Fm直到重度干旱胁迫下仍没有明显的降低，且复水后光合能力恢复程度较高，即干旱没有给这两个品种造成严重的光破坏，而两个品种之间，葡萄园皇后在重度干旱胁迫下的φPSⅡ明显低于赤霞珠，说明其光合器官在严重干旱胁迫时对光能的利用率较差；新品种皇家秋天和东方品种群的里扎马特在中度干旱胁迫下仍可维持较高的Fv／Fm和φPSⅡ，但在重度干旱胁迫下则降低幅度较大，说明其抵御极端干旱胁迫的能力较差；欧美杂种红双味的Fv／Fm和φPSⅡ随着干旱胁迫程度的增加呈现平缓的下降趋势，而且其φPSⅡ在重度干旱胁迫下是七个品种中最高的，这应该与其此时仍维持较强的光呼吸活性有关；红地球和砧木1103Paulsen的Fv／Fm和φPSⅡ在轻度干旱胁迫下就明显下降，表明干旱条件下其抵御光抑制的能力较差。

The maximum rate of decomposition of soil organic carbon insubtropical wetness area is red soil under coniferous and broad-leaved mixed forest＞yellowsoil under grass＞yellow soil under shrub＞yellow soil under broad-leaved forest＞red soilunder camellia oleifera; decomposition rate of yellow soil is faster than red soil. Themaximum rate of decomposition of soil organic carbon in subtropical wetness zone isyellow-brown soil under mixed forest in Nanjing＞red soil under adult fir in Yujiang＞redsoil under broad-leaved forest in Yujiang.

湿润亚热带地区森林土壤有机碳分解速率最大值出现在培养初期的一周内，其顺序：针阔混交林红壤＞茅草黄壤＞灌木林黄壤＞常绿阔叶林黄壤＞油茶红壤，同一植被下黄壤有机碳分解速率大于红壤，南京混交林黄棕壤＞余江杉木(32年)红壤＞余江常绿阔叶林红壤。

The thesis can be divided into five parts as follows: First, the structural characteristics of finned-pipe evaporator are analyzed. After selecting suitable microelement controller, the heat-transfer and mass-transfer processes are analyzed for every microelement under the conditions of dryness, wetness and frostiness. Based on previous equations, some parameters of frostiness are confirmed and the frost-growing model is set up under frost condition. Some hypotheses are postulated and with the help of the equation of mass-conservation, energy-conservation and momentum-conservation, the evaporation model which fits in the dynamic simulation is built, which set a solid foundation for system simulation. Second, the starting and stopping behaviors under disturbed condition are analyzed and calculated by using the dynamic concentrative parameter model, which gives some advice to better prescribe refrigeration system and set theoretic foundation for carrying out automatic control of refrigeration system. Third, the normal running process is analyzed and calculated by means of rational matching theory, which gives some advice on how to better understand the parameter change under steady state and the affection of inlet-parameter on evaporator. Fourth, the simulation software with dynamic characteristic is designed, which can be applied to calculate thernio-parameter of cryogen, air humidity and frost thickness under different initial and boundary conditions, and to carry out dynamic simulation under conditions of dryness, wetness and frostiness, at the same time, to achieve detection and simulation at any stage from starting to stopping.

本文的主要内容如下：1对翅片管蒸发器结构特点进行分析，选取适当的微元控制体，就干、湿和霜工况下对每个微元分别进行传热传质分析，基于经验关系式确定霜的有关参数，对于霜工况下的霜生长建立模型，经适当假设，运用质量守恒、能量守恒和动量守恒方程建立适合动态仿真的蒸发器数学模型，为系统仿真奠定基础； 2对蒸发在大扰动下的开、停机过程，运用动态集中参数模型进行分析和计算，为更好地描述制冷系统运行的全过程奠定基础，同时也为制冷系统实现自动控制提供一定的理论基础； 3对蒸发器正常运行过程，运用动态分布参数和参数间定量耦合的观点来分析和计算，为更好地了解稳态工况下各点参数的变化情况及各入口参数对蒸发器动态特性的影响即蒸发器性能对各参数变化的敏感性； 4编写翅片管蒸发器动态特性仿真计算程序，可以计算不同边界条件和初始条件下的制冷剂热力参数、空气温湿度和霜厚度分布场，实现对翅片管蒸发器在干、湿和霜工况下的动态仿真。

The vibrations can be effectively suppressed under various operation modes, including chopping control and single pulse control, by adopting the novel control strategy. Furthermore, the novel control strategy minimizes the torque ripple under the torque chopping control.

采用新的控制策略，在斩波控制和单脉冲控制下，振动都可得到有效抑止，且新控制策略可在转矩斩波控制下减小转矩脉动。

By the balance of communication link power, SNR balance guidelines and BER balance, under the base to meet the requirements of systems and not affecting thequality of call. Finally, the open-loop/closed-loop variable step length reverse power control is introduced, its principle is under the original open-loop power control to select suitable power control step by the new power control bit, and achieves a balanced system fastest and most effective.Keywords: Step, Power-control, Brethren interference, Proximity effect

依据通信链路的功率平衡准则、信噪比平衡准则和误码率平衡准则，在满足系统要求和不影响通话质量的基础上，最后提出了开环/闭环可变步长的反向功率控制，其原理是在原有的开环功率控制的基础上，依据新的功率控制比特，来选取合适的功率控制步长，以最快、最有效的方法使系统达到平衡。

The mechanical behavior of Shape Memory Alloys material is tested, and the constitutive model of the SMA is established. A kind of SMA combined rubber isolator is developed, and the isolation effect of the SMA combined rubber isolator for long-span bridge and tall building structures is numerically simulated, from which the adaptive isolation performance and the self-restoring capacity of the SMA combined rubber isolator are verified. A kind of SMA damper is developed, the mechanical behavior of the SMA damper is tested, and the model of restoring force of the SMA damper is established. The theory and method of adaptive control based on the SMA damper for the long-span bridge are built, and the effectiveness and reliability of the adaptive control for the long-span bridge using the SMA damper are verified through numerical simulation and model test. The MRF-04K type magnetorheological damper is developed, the mechanical behavior of the MR damper is tested, and the model of restoring force of the MR damper is established. The theory and method of adaptive control based on the MR damper for the long-span bridge and tall building structures are built, and the effectiveness and reliability of the adaptive control for the long-span bridge and tall building structures using the MR damper are verified through numerical simulation and model test. In addition, the theory and method of sub-structural damage identification for long-span bridge are derived, the influence of soil-structure dynamic interaction on the seismic isolation and control effects with different isolation and control measures and the damage responses and the sliding base-isolation of large structures under the excitation of underground explosion are investigated.

试验研究了形状记忆合金材料的力学性能，建立了SMA材料的本构模型；研制了一种SMA复合橡胶隔震支座，数值仿真分析了应用SMA复合橡胶支座的大跨桥梁和高层建筑结构的隔震效果，从而验证了SMA复合橡胶支座的自适应隔震性能及其震后自恢复能力；研制了一种SMA阻尼器，试验研究了SMA阻尼器的力学性能，建立了SMA阻尼器的恢复力模型，建立了基于SMA阻尼器的大跨桥梁结构自适应控制理论与方法，通过数值仿真与模型试验验证了大跨桥梁结构SMA阻尼器自适应控制的有效性与可靠性；研制了一种MRF-04K型磁流变阻尼器，试验研究了MR阻尼器的力学性能，建立了MR阻尼器的恢复力模型，建立了基于MR阻尼器的大跨桥梁和高层建筑结构的自适应控制理论与方法，通过数值仿真和模型试验验证了大跨桥梁和高层建筑结构MR阻尼器自适应控制的有效性与可靠性；还建立了大跨桥梁结构的子结构损伤识别的理论与方法，研究了土-结构动力相互作用对不同隔震和控制措施的减震控制效果的影响以及地下爆炸波作用下各类大型结构的灾害响应与滑移隔震。

The compatibility of both Gvirens and B.firmus was researched. The fermentation filtrate of Gvirens , under the concentration of 70%, had not distinct inhibitory activity to B.firmus, the biomass of B.firmus would decrease with above the 70% filtrate of Gvirens, but the fermentation filtrate of B.firmus had not inhibitive role to Gvirens. 7, The cooperation control of both Gvirens and B.firm to the pine needle blight was explored:(1) Pathogen inoculation happened prior to the bio-control treatment for 7 days, however, the disease index and control effect had not distinct differences in any treatments even if combination of the two antagonists, but the susceptibility for different kind of pine were different.(2)when antagonist and pathogen were inoculated at the same time, some control effect to the pine needle blight, including certain extent cooperation control of both Gvirens and B.firm were proved, but it wasn't distinct when two antagonists used separately, and the change of the antagonist concentration had little effect to the control effect.

G.virens与B.firmus对松赤枯病的协同控制显示：(1)预先接种病菌后(7天)再进行生物防治处理，不管那种情况，感病指数和防治效果在处理间差异不明显，浓度影响无显著差异，即使是两种生防制剂联合作用也未显著提高其防效，但不同树种间的感病性有明显差异；(2)领抗菌与病原菌同时接种，对松赤枯病有一定防治效果，两菌联合有一定的协同作用，两菌分别单独施用防效差异不显著，浓度变化对防效影响不大；(3)预先接种颇抗菌能显著提高防治效果，两菌联合处理防效更优，感病树种的感病指数可降至13一15，抗病树种的感病指数可控制在3%左右；在同一浓度下B.f1'r功US、叹叮厂即s间无显著差异，在同一领抗菌下，浓度愈高，防效愈高：松，(4)三种生防接种方式的平均效果分析表明，叹F行ens最高平均防效49.5%黑 B。

In the last chapter,we study the control problems of the distributedparameter system governed by a class of higher order pseudohyperbolicequation related to the symmetric regularized long wave equation.we havediscussed the controllability and optimal control problems.we have obtainedcompatibility condition of the constraint when the state is controllable,therepresentation of the optimal control for both the time optimal control problemand the optimal control problem of minimum energy type,and the equationsatisfied by the minimum time.we have shown that the optimal control belongsto the boundary of the admissible control set.

在第六章中，我们研究了与对称正则长波方程相关的一类高阶拟双曲型方程支配的分布参数系统的控制问题。讨论了系统的状态能控性问题和最优控制问题，给出了状态能控时的约束相容性条件，给出了最速控制问题、最小能量型最优控制问题的最优控制表达式和最速时间所满足的方程式，证明了最优控制属于控制集合的边界。

This matter overthrew all basises I learned from Sunday school .

这件事把我从周日学校学到的所有道理都颠覆了。

It's one of the cruel ironies of aging: if you want to remember your favorite restaurants, the less you should eat at them.

这是一个老化的残酷讽刺：如果你想记住你最喜欢的餐馆，你应该更少吃到它们。