查询词典 Bessel

A new method based on the Fourier-Bessel series is proposed to calculate the higher-order harmonic components of a nonlinear ultrasound field in absorbing medium and an analytical solution of a series form is obtained. A closed analytical solution of the higher-order harmonics in the zeroth-order Bessel ultrasound field and the focused Gaussian ultrasound field is deduced to study the field property, especially the near-field property.

提出了一种基于Fourier-Bessel级数的新方法，用于计算吸收媒质中非线性超声场的高次谐波分量，得到其级数形式的解析解，由此推导出吸收媒质中零阶Bessel超声场、Gauss聚焦超声场高次谐波的封闭解析解，进而对其声场特性尤其是近场特性进行了研究。

The fundamental and higher-order harmonic ultrasound fields of a zeroth-order Bessel ultrasound field and focused Gaussian field in absorbing medium are computed and simulated by solving the KZK equation using a frequency domain finite difference method.

通过频域有限差分方法求解KZK方程，对吸收媒质中的零阶Bessel超声场、Gauss聚焦超声场进行计算，得到基波和高次谐波声场的数值解和仿真图，计算仿真结果验证了上述的理论结论。

The potential functions of incident and scattered waves were expanded into Fourier-Bessel series, and the coefficients of scattering waves field were determined by imposing continuity conditions of stress and displacement at the soil-pile interfaces with the help of a set of cylindrical coordinate systems and in accordance with the Graff's addition theorem.

将倾斜入射波和散射坡的势函数展开成Fourier-Bessel函数的无穷级数的形式，利用一组圆柱坐标系统和Graff加法转换定理，通过施加桩土界面处的应力和位移连续的边界条件，求解出散射波势函数的待定系数，进而得到饱和土体中任意点的位移和应力。

Propagation properties of high-order Bessel-Gaussian beam through a misaligned first-order ABCD system have been studied by using the generalized Huygens-Fresnel diffraction integral and augmented matrix .

使用广义惠更斯-菲涅耳衍射积分和增广矩阵，研究了Bessel-Gaussian光束通过失调一阶ABCD系统的传输特性。

Many types of optical transmission, and here I step on the weak-guided wave fiber wave equation to study and understand the step-index optical waveguide mode, are second-order differential equations Bessel equation.

光纤传输的种类很多，在这里我只对阶跃型弱导波光纤波动方程进行研究，了解阶跃折射率光纤的波导模式，得到二阶微分方程Bessel方程。

Code of drawing a map in Bessel Newmann function, WINDOWSthe generalized Bessel equation and the Hankel function.

并利用球Bessel函数与半奇数阶Bessel函数的关系计算了本征函数的模方。

By means of variable substitution, it is found that the differential equation of motion is a Bessel equation. Based on the equation, responses of elastic displacement, velocity, acceleration of skip and cable tension close to sheave were deduced.

通过变量代换，发现箕斗运动微分方程是可求解的Bessel方程，从而得到了装载过程中箕斗的弹性位移、速度、加速度和天轮处钢丝绳的张力的解析表达式。

Moreover, the quasi-analytical expressions of the relative concentrations at the mobile region and the immobile region are deduced respectively by using Bessel equation, Bessel function and the method of Laplace transform under the initial concentration zero and the first or second boundary condition of a semi-infinite one-dimensional space.

并分别在初始浓度为零，半无限一维空间内第一类边界条件和第二类边界条件下，利用Bessel方程、Bessel函数和Laplace变换法推导出了可动区和不动区溶质相对浓度的准解析表达式。

Within this framework we develop a theoretical approach to interpret photoelectron angular distributions in terms of a generalized phase Bessel function which can determine the principal features of the distribution and its variation with laser frequency and intensity.

文章作者及其合作者发展了光电子角分布的处理方法，利用复合相位Bessel函数来表征光电子的跃迁几率幅，将光电子的角分布与复合相位Bessel函数直接联系起来。

The mutual connection that analyses Bessel beam of light and Bessel-Gauss beam of light theoretically reachs distinction, beam of light of Bessel of numeric imitate ideal and Bessel-Gauss beam of light are in the radial light intensity of aleatoric plane distributings, and the influence that smooth waist radius and syntonic antrum antrum grow pair of output Bessel-Gauss beam of light.

梗概： 理论分析Bessel光束和Bessel-Gauss光束的相互联系及区别，数值模拟理想Bessel光束和Bessel-Gauss光束在任意平面的径向光强分布，以及光腰半径和谐振腔腔长对输出Bessel-Gauss光束的影响。

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％。