查询词典 field intensity

Our theory predicts the minimum value of ponderomotive parameter and the corresponding critical laser intensity, below which no diffraction can occur; 6, We studied the energy transfer of a two-level atom moving in a cavity field, as well as its influence on the atomic emission spectra and on the photon distribution of the intro-cavity field.

我们用两对激光模来模拟紧聚焦的高斯光场，成功地得到了《Nautre》上Batleaan等人的实验观测结果，预言了有待实验进一步观测的新现象，并确立了发生电子衍射的激光场的临界强度； 6，研究了原子在激光场中运动时光场与原子之间的能量交换，以及这种能量在光谱上的反映和对激光场统计性质的影响。

The results of this study indicate that changing the angle of the intake port has a profound effect on the flow field during the intake stroke of the engine cycle. For the case with the intake-exhaust valves canted at zero degree (the so-called vertical valves), the tumble ratio, swirl ratio, turbulent intensity, and turbulent kinetic energy in the direction perpendicular to the bisecting plane of the cylinder are at their highest levels than those obtained for the other cases. This effect is most pronounced after the compression stroke of the cycle. As a result of this study, it is observed that the behavior of the overall flow field from the intake to the completion of compression stroke has a major impact on the effectiveness of the mixing of fuel-air prior to the ignition of the engine cycle.

结果显示，改变进排气阀的倾斜角度对进气期间的流场变化有很明显的影响，其中以垂直阀(进排气阀倾斜0度)所得的 Y轴向(Y方向系垂直於将汽缸对分为二平面的方向)滚流强度、涡漩比、紊流强度、紊流动能等流场强度为最强；若以流体经活塞压缩后的流场特性进行探讨，所得结果显示压缩冲程对汽缸内流场的效应是不容忽视的；因此由进气到压缩过程结束的整体流场现象，才是影响引擎点火前的油气混合程度与燃烧品质的关键。

In this text,according to home and abroad scholars's study on design of sonochemical reactor and parameters of ultrasound cavitation, I designed the sonochemical reactor cohered with transducers on its side wall, and study cavitation field and ultrasound field distribution by changing power and frequency ,and made research in absorption of different power and frequency ultrasound traveling in water, and especialy study the cavitation with different sound intensity.

笔者综合国内外学者关于声化学反应器的设计思路，设计了侧壁黏结换能器清洗槽式声化学反应器，改变频率定性测量反应器中的声场和空化场分布，研究不同频率的超声在水中传播的吸收情况、声空化和声压或声强的关系以及一定频率的超声在水中的有效空化范围。

As an example, the deposited oil Offshore Platform BZ28-1 of BohaiOil Field in China was numerated with genetic algorithms. The results show that the proposed method is significative in the design of the platforms.5. Theory and method of optimum design of earthquake-resistant structures based on optimal fortification intensity were introduced. Optimum design was performed for Platform BZ28-1 of Bohai Oil Field in China according to principle of three-level fortification and aseismic design method of two-stage of code for aseismic design of buildings.

介绍了基于最优设防烈度的抗震结构优化设计的理论和方法，并以渤海油田BZ28-1储油平台为例，在目标函数中既考虑了结构的造价又考虑了损失期望，根据&小震不坏、中震可修、大震不倒&三个水准的抗震设防原则，利用抗震规范的&二阶段&抗震设计方法，对其进行了结构优化设计，得到了考虑造价和损失期望、基于最优设防烈度的最优设计方案。

Small signal solution of aberrated second harmonic generation is deduced from three-dimension three wave coupling functions. The numerical work gives out lot of results of different aberrations. The effects of the fundamental wave's aberrations, which will change the conversion efficiency, distribution of intensity and phase in the frequency conversion, is analyzed. It shows that when walk-off and diffraction effects could be ignored approximately estimation of the phase distribution of second-harmonic wave could be done. The far field divergent angle and second moment radius of harmonic wave will vary with the aberration of fundamental wave, but the far field divergent angle will be obviously smaller than that of fundamental wave. The phase distribution of both fundamental and harmonic wave is measured using Hartmann-Shack wave front sensor in the experiment with 1064nm and 790nm lasers, respectively. Results are given.

首次从三维三波相互作用方程组推导得到了位相畸变光束倍频的小信号解；通过建立三维数值模型，编写相应仿真程序，首次得到了位相畸变光束倍频过程的大量计算结果，深入细致地研究了位相畸变光束经非线性光学频率变换后谐波的转换效率、光强分布、位相分布以及影响它们的各种因素；得出谐波的远场发散角和光斑二阶矩的变化规律会因为基波像差的不同而不同，但谐波的远场发散角明显地比相应基波的小的结论；得到了在走离效应和衍射效应等影响许多因素可以忽略的情况下，位相畸变传递到二次谐波的估算式；举例分析了KDP三倍频方案中，基波位相畸变对二次谐波和三次谐波的影响；实验工作中，用哈特曼-夏克传感器分别对1064nm倍频过程和790飞秒超短脉冲倍频过程中的基波和谐波的位相分布进行了测量，给出了相应结果。

Firstly, B-scan ultrasound images are captured form patients and the regions of interest are localized. During the feature extraction approach, three models are employed including mean intensity ratio of the near field and the far field, the gray level co-occurrence matrices and the gray level run-length matrices. 10 statistics are extracted from the three models for each image.

首先以脂肪肝B超图象纹理的变化为出发点，分别采集人体肝脏的B超图象，并选择图象中的感兴趣区域，计算出每一幅图象的近远场灰度比特征、灰度共生矩阵和灰度游程矩阵的二次统计量特征。

Flashover voltage under coaxial electric field depends on the electric intensity on the inner electrode surface and uniformity degree of radial electric field.

同轴电场下的闪络电压主要由内电极表面电场与径向电场分布的均匀程度决定。

Four types electromagnetic stirrers, such as round, half round, U shaped and modified U shaped, were used in the simulation and their effects of structure, coil current intensity and magnetic field frequency on the magnetic field distribution and the flow filed in the immersion nozzle and mold during the round billet continuous casting of steel were numerical simulated and analyzed.

在浸入式水口外部采用可移动的旋转电磁场装置，使水口内钢液形成旋转流动。

The main research tasks and results are as follows:(1) Through comparing the stress intensity factor of compact tension specimen calculated by finite element software with the theoretical value, the feasibility of calculating fracture parameters of crack tip in ABAQUS software was verified.(2) The relationship between the elastic modulus of the material and research scale was studied based on deriving the cohesive stress theory and other relevant theories. And the elastic modulus of the material on meso-scale was determined.(3) Global model and sub-model of the finite element were built in th...e macro-scale, and stress-strain field nearby the crack tip was analyzed, and the results show that the detailed stress-strain in the crack tip could be obtained by using the sub-model technique.(4) In meso-scale, the crack growth model was also established by assuming the crack propagating along the grain boundary, and the detailed stress-strain field in the crack tip was obtained.(5) The effect of crack length on Von Mises stress, and maximum principal stress and strain was analyzed in meso-scale when equivalent KI equals 30MPa.m1/2. And the results show that except for crack tip area, the stress-strain distribution in whole specimen is not affected.

主要完成研究内容和取得成果如下：(1)利用有限元软件计算出紧凑拉伸试样的裂纹尖端应力强度因子KI值，其结果与理论值一致，从而验证了利用ABAQUS计算裂纹尖端相关断裂参量的可行性；(2)在研究内聚应力等相关理论的基础上，推导出了研究尺度与材料弹性模量的近似关系，并确定了介观尺度上的弹性模量；(3)在宏观尺度上建立了全局有限元计算模型和子模型，得到了裂纹尖端应力应变场分布，结果表明利用子模型技术获得比较准确的裂纹尖端应力应变场分布是可行的；(4)在介观尺度上利用平均晶粒尺度的方式建立了裂纹沿晶扩展模型，得到了裂纹尖端断裂过程区的微观应力应变场；(5)当应力强度因子为30MPa.m1/2时，分析了介观尺度上在裂纹沿晶扩展过程中裂纹长度对Mises应力、最大主应力和应变的影响，结果表明，裂纹扩展长度对试样整体应力应变分布影响不大，而对裂纹尖端区域有较大影响；(6)介。。。

The analysis showed that the great value area of correlations is consistent between sea-level pressure field, 500hPa geopotential height field and intensity index of East Asian summer monsoon in Northeast China in pre-winter or summer, and the correlation is more better in summer than in pre-winter.

结果表明，前冬季和夏季海平面气压、500hPa位势高度与东北地区夏季风强度指数的正负相关大值区的分布基本一致，但夏季相关性更明显；海表温度与东北地区夏季风强度指数的相关不明显；北极海冰密集度与东北地区夏季风强度指数的相关性较好，前冬季以负相关为主，夏季以正相关为主；各振荡指数中只有NPO指数与东北地区夏季风强度指数有很好的相关性。

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。