半径范围

The results indicate that: the cavity radius becomes stable at approximately 6000μs;the blasting pressure waves mainly are transmitted horizontally;the peak pressure has a negative logarithm relationship with distance perpendicular to the charging bisector;and the valid influence area r.

应用ANSYS/LS-DYNA有限元程序对条形装药黄土地基中爆炸过程进行了三维数值模拟，发现在6000μs爆炸空腔已基本稳定，条形装药爆炸产生的压力波以水平方向传播为主，装药中垂线方向爆炸产生的峰值压力与离中垂线距离呈负对数关系，土的有效影响范围半径大约为爆炸后形成的空腔半径的4倍。

A coronagraph uses an occulting disk to create an artificial eclipse, revealing the corona and objects hidden in the solar glare. C2's field of view extends from about 2 to 6 solar radii, while C3's runs from about 4 to 32 solar radii.

日冕仪利用一个遮光板产生人造日食，使得淹没在太阳强光中的日冕和其他天体显现出来）。C2照相机的视野范围在2到6个太阳半径之间，C3的视野在4到32太阳半径间。

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。

The result indicates that the output power oscillates and weakens along with increasing input power,and its oscillation period depends on the distance between the medium and beam focal point.Limiter′s limiting ability will decrease if waist size of the incident Gaussian beam and the aperture size increase.With a fixed input power scope,medium′s best limiting position will move towards the focal point if waist size of Gaussian beam and the aperture size increase,but the best limiting position will change a lot with different input power scopes.

结果表明：限幅器的出射功率随入射功率的增加衰减振荡，其振荡周期取决于介质相对于光束焦点的位置；限幅器的限幅能力随入射光束腰半径和光阑孔径的变大而减弱；入射功率范围固定，入射光束腰半径和光阑孔径增大时，介质的最佳限幅位置向入射光束的焦点靠近，但是在某些入射功率范围内会存在多个最佳限幅位置；光限幅器的箝位输出功率随光阑线性透过率的增加存在线性增加和非线性增加两个不同区域，实际应用中应在线性增加区域确定光阑孔径的大小。

This project studies the scale-dependent deformation behavior of the metal matrix composite, the void nucleation and void growth mechanisms at the micron/submicron scale. The main results are:(1) In prophase, growth and coalescence of the void embedded in the graded matrix are analyzed in detailed;(2) Based on the infinite solid model containing a micro-void, coupling effects of the void shape and the void size on the void growth are studied carefully, the results show that it seems to exist a critical equivalent void radius, which is associated with the material length. When radius of a microvoid is close to or smaller than the critical void radius, the micro-void growth rate is essentially eliminated;(3) The coupling effects of the particle shape and size on the mesoscopic stress fields within the particle and matrix are also investigated by introducing the conception of inclusion/matrix interfacial energy. The results show that the stress concentration factors within the particle and on the matrix/particle interface are also strongly size-dependent,so the void nucleation mechanism is size-dependent.(4) By employing a specific orthogonal curve coordinate frame and a 'kernel function' conception, a 'unified method'solving the spheriodal and spherical void problems is suggested; by this unified method, size-dependent plastic potentials of the porous materials containing the spheriodal or spherical voids are obtained, which extend the traditional Gurson model for the spherical void and GLD model for the spheriodal voids to the micron scale.(5) Based on the RVE model containing the spheriodal or spherical particles, the influences of the particle shape and size on the size-dependent mechanical behavior of metal matrix composite are studied.

中文摘要：本项目对金属基复合材料在微细观尺度下的尺度相关变形行为、孔洞形核及长大的机理和模型进行了研究，取得了如下主要结果：1）在前期研究中，探讨了基体的梯度分布对孔洞长大和聚合的影响；2）基于含孔洞的无限大体模型，探讨了孔洞形状和孔洞尺寸对其长大的耦合作用，结果表明：可能存在一个与材料特征长度相关的临界孔洞尺寸，当椭球孔洞的等效半径小于临界孔洞半径时，孔洞的长大受到明显抑制；3）通过引入基体/夹杂界面能的概念，分析了夹杂尺寸、夹杂形状对材料细观应力场的耦合影响，结果表明：颗粒内部和界面上的应力集中因子强烈地依赖于夹杂的尺寸和形状，因此，孔洞的形核机理是尺寸相关的；4）采用一种特殊的正交曲线坐标系和引入"核函数"的概念，"统一"地得到了含椭球和球形孔洞的材料的尺寸相关塑性势，它将传统的Gurson球形孔洞模型和GLD椭球孔洞模型推广到微尺度范围；5）基于含椭球和球形夹杂的体胞模型，初步研究了夹杂形状、夹杂尺寸对金属基复合材料尺寸相关力学行为的影响。

Secondly, the model of the passengers forecast were studied. The corridor analytic method was proposed in the metropolis rail transit passenger flow forecast application, The traffic district for passengers forecast was raised, which is centered on the hub, circled with the radius of attrahent scope .The forecast model applying toestimating the volume of collecting and dispersing passenger generation and transfer passenger distribution are raised, the example proved that the models are reliability and practicable.Thirdly, the plan theories of metropolitan rail transit were studied.

研究了都市圈城际轨道交通客流预测的方法；提出了走廊分析法在都市圈城际轨道交通客流预测中的应用，提出了以枢纽节点为中心、以吸引范围为半径的圆形范围为客流预测的虚拟交通小区的划分方法；并依此在确定吸引范围的基础上，提出了基于效用矩阵的都市圈轨道交通客流预测模型，实例分析证明该方法具有较强的实用性和可靠性。

The results showed that: with the regression analysis of Betula platyphylla, Pinus koraiensis, Abies nephrolepis, Picea koyamai var koraiensis, and Betula costata, there was a significant negative correlation between neighborhood interference index and the growth (0.40~0.89) and the correlation extent depended on the neighborhood influence zone and slope. The neighborhood influence zone corresponding to maximal regression coefficient R~2 was the neighborhood influence radius. Based on the linear subsection regression between neighborhood interference index and influence zone of five species, the neighborhood interference index increased with the increasing zone and there was a previous increasing trend in a certain scope, while the increasing trend slackened beyond the zone. The neighborhood influence zone corresponding to transition point was the neighborhood influence radius. The neighborhood interference index positively correlated with the neighborhood influence zone and the range of R~2 was 0.40-0.64. With the analysis of tree cores of Juglans mandshurica, Fraxinus mandshurica at middle and lower slope in a plot which was fostered in 1995, the distance which the growth release farthest neighborhood and object stub was judged, thus the neighborhood interference radius was inferred. According to the studies, we found that the neighborhood interference radius was different among different trees, even if the neighborhood interference radius of the identical tree species also had the difference at different slopes.

结果表明：通过对白桦、红松、冷杉、红皮云杉和枫桦树种进行邻体干扰指数与生长量回归分析发现，邻体干扰指数与生长量呈显著负相关(0.40～0.89)，相关程度因邻体影响范围和坡位而异，R~2达到最大值所对应的影响范围即为邻体影响半径；通过对白桦、红松、冷杉、红皮云杉和枫桦树种进行邻体干扰指数与影响范围的线性分段拟合，邻体干扰指数随影响范围的增加而增加，其在一定的范围内上升较快，而超出该范围后上升的幅度变慢，变化的转折点所对应的影n向范围可以判定为邻体影响半径，线性回归显著(0.40～0.64)；通过对1995a抚育的胡桃楸、水曲柳样树进行研究，分析邻体树种的中坡位和下坡位的生长锥芯，判断产生生长释放的最远邻木与基株树桩所对应的距离，推断邻体影响半径；根据研究发现，邻体影响半径因树种不同有一定的差异，即使同一树种的邻体影响半径在不同坡位也有一定的差异。

Results indicate that radial distance of the bushing from the rotor center and the radius of the hemispherical bushing significantly affect wear rate,and minimzing both two values will result in lowest wear for micro-rotor systems in MEMS.However,it is noted that the bearing radius sets a lower limit on the hemispherical bushing radius since the bushings are located beyond the rotor inner radius.It is desirable to reduce their effects on friction and wear on micro-rotors by regulating the radius of the bushing and the radial distance of the bushing from the rotor center within permissive range of micro-fabrication.Severe wear exists with increasing applied load and rotating speed of the rotor.Stress distributions in the contact region are different from Hertz solutions due to the convergence stresses apearing on the uncontinuous curvature line and the contact pressures display symmetrical parabola in the contact region.

结果表明：在MEMS微转子系统中，微转子轴衬偏心距离和转子轴衬半径影响线磨损率，以两者减至最小为较理想，但须注意设计中轴承半径的限制，并使轴衬偏心距离大于轴承内半径；在转子加工制造许可的范围内，可以通过调整转子轴衬的半径和偏心距离来减少摩擦磨损对微电机的影响，随着转子所承受载荷和转子旋转速度的增加，其磨损严重；接触区的应力分布不同于经典Hertz解，这是由于应力集中出现在不连续的曲率线上，且接触区的接触压力呈现轴对称抛物线状分布。

Some primary metering grooves with different curvature radiuses and geometrical dimensions were designed,and the hydraulic characteristics of them were all tested Based on the experiment results, different flow characteristics of them were obtained The great differences between the experimental results and the conventional theoretical predictions were found by the comparison between them Under the condition of this experiment, the critical Reynolds is 1000～1200, and is diminished as the decrease of th...

为了在设计层板发汗冷却推力室时选择合适的一次调节通道，对不同曲率半径、不同几何尺寸的一次调节通道进行了流阻试验，得出了不同几何尺寸的一次调节通道的流动特性。试验结果与经典的层流理论计算结果之间存在较大的差异。试验表明，一次调节通道的临界雷诺数随曲率半径的减小而减小，摩阻系数随曲率半径的减小而增加，并得出了相应条件下的一次调节通道摩阻系数的修正关系式，在层流范围内能较好地反映一次调节通道的流阻特性

A method was discovered to disable these ELF towers from exerting their mind control functions by placing a simple device known as an orgone generator within a radius of 1,300 feet of these towers.

一种方法被发现可用来使这些ELF塔不能实施它们的精神控制功能，这种方法是通过在这些塔周围1300英尺半径范围内布置一台简单的名为奥冈发生器的设备来实现。

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。