查询词典 Bessel functions

While calculating tensor Green's functions, the algorithm of secondary division is adopted to solve the singular problem. The Gaussian quadrature and continued fraction is adopted to calculate the integral with Bessel function. This method not only can ensure the right calculation of tensor Green's functions but also can get high precision.

求取张量格林函数积分时，采用二次剖分算法解决计算中奇异值问题，对于含有贝塞尔函数的积分项，利用结合连分式展开的高斯求积代替常规的快速汉克尔变换方法，确保了张量格林函数的正确计算并提高了计算精度。

In order to study the propagation of partially coherent modified Bessel-Gaussian beams passing through a paraxial ABCD optical system with hard-edge aperture,the approximate analytical propagation equation was derived with the hard-edged aperture function expanded into a finite sum of complex Gaussian functions.

为了对部分相干修正贝塞尔－高斯光束通过有硬边光阑近轴4BCD光学系统的传输进行研究，采用将硬边光阑窗口函数展开为有限个复高斯函数之和的方法，得到了近似的解析传输公式。

Diffraction by helices It may be shownthat the intensity distribution in the diffraction pattern of a series of points equally spaced along a helix is given by the squares of Bessel functions.

衍射螺旋这可能是显示的强度分布的衍射图样的一系列点同样距离的沿螺旋给予的平方贝塞尔函数。

The squares of Bessel functions are plotted about O on the equator and on the first , second, third an fifth layer lines for half of the nucleotide mass at 20 A. diameter and remainder distributed along a radius, the mass at a given radius being proportional to the radius.

的平方贝塞尔函数绘制关于澳赤道和第一，第二，第三行的第五层的一半，在20个核苷酸大众答：直径和其余分布在半径，大众在某一半径正在比例到半径。

Steady-state harmonics and transient performance of the conventional static synchronous compensator controllers are first investigated. Based on the sensitivity analysis of the STATCOM output power, it is found that the voltage magnitude is more effective than the phase angle in controlling the reactive power output. An analytical approach to harmonic analysis of a STATCOM based on Bessel functions of the first kind is described.

本博士论文首先分析传统静态同步补偿器(Static Synchronous Compensator， STATCOM)控制器的优缺点，利用对静态同步补偿器输出功率的灵敏度分析，得知要控制补偿器输出虚功大小时，直接对静态同步补偿器输出电压大小作控制，会比对相角作控制来得有效。

To match the boundary conditions, the modified Bessel functions are expanded to the planar wave in the interface. Then the eigenvalue equations of different polarizations are obtained by scalar approximation. At last, the relations between propagation losses and the states of polarizations, the geometric structures of the fiber, the refractive index and thickness of the polymer are calculated.

论文首先给出其等效折射率数学模型，在纤芯和包层中，光场用贝塞尔函数及虚宗量贝塞尔函数的求和表示，在聚合物和金属中用指数函数的求和表示，交界面上采用将虚宗量贝塞尔函数用平面波展开的方法匹配边界条件，然后利用标量近似求出极化D型光纤不同偏振态光场模式的本征值方程，最后通过数值计算得到光纤的传输损耗与抛磨平面和纤芯之间的距离，聚合物粘接材料的折射率和厚度，以及偏振态之间的关系。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。