查询词典 bessel function of the third kind

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。

In the fiber cladding and core, the optical fields are represented by the sum of the Bessel and modified Bessel functions, respectively. In the polymer and metal, the optical fields are written to the sum of the exponential functions.

针对热极化光纤的特点，本论文完成了以下理论分析和实验工作： 1、首次利用圆波导模型和标量近似理论对具有复杂几何结构的极化D型光纤的传输特性进行了理论分析。

Finally the connections between the Lebesgue measure for its image and Bessel-Ricsz capacity are discussed and an explicit Bessel-Riesz capacity estimate is obtained.

利用鞅的方法讨论了广义布朗单的碰撞概率与容度之间的关系，给出了其碰撞概率的容度估计。

In this paper, the propagation and focus properties for several modes describing hollow beam are analyzed, and the focus properties for hollow gaussian mode are particularly discussed. Furthermore, a new mode, high-order Bessel-Gauss mode, is put forward to describe hollow beams. The results for high order Bessel-Gauss beams propagating through lens focusing system and free space are derived by terms of Collins integral formula.

本文分析了几种描述空心光束数学模型的传输特性和聚焦特性，着重讨论了描述非中空光束的数学模型的聚焦特性；同时提出了一种描述完全中空的空心光束的新模型――高阶贝赛耳高斯模型，并且运用Collins积分公式，分析了这种新模型的空心光束的传输特性和聚焦特性。

The double integration can be simplified to standard Bessel integration through the relation of Bessel functions.

利用贝塞尔函数的性质可将该二重积分化为标准的贝塞尔积分，然后采用直接数值积分的方法计算该积分。

Though comparing Canny operator and center B spline dyadic wavelet, the following conclusion is proven in this dissertation: a Center B spline function has tight support and Canny operator hasn't. b Center B spline function asymptotic convergence to Gaussian function and the derivative of Center B spline function asymptotic convergence to Canny operator. c The derivative of fourth order center spline B function is more suitable as a optimal edge detector than Canny operator. d Center B spline function can balance the smoothing and approximation of original data, and the fourth center B spline function is the only optimal solution of two order smoothing problem. e The error between the valve of time-frequency uncertainty of the fourth center B spline function and the lower bound of time-frequency uncertainty does not exceed 0.143% of the lower bound. f The derivative of center spline B function can construct a stability dyadic wavelet and can give a fast algorithm for multiscale edge detection, but Canny operator can do neither.

作者给出了Canny算子与中心B样条二进小波严格的比较证明，得出如下结论：a中心B样条函数具有紧支集，Canny算子不具有紧支集。b中心B样条函数的极限收敛于高斯函数，中心B样条函数的导数收敛于Canny算子。c四阶中心B样条函数的导数比Canny算子更接近最佳边缘检测滤波器。d中心B样条函数比高斯函数更能兼顾对原函数平滑和逼近的折中要求，并且四阶中心B样条函数是二阶逼近问题的唯一最优解。e四阶中心B样条函数的时频测不准关系值与时频测不准关系下界的逼近误差不超过0.143％。f中心B样条函数的导数可以构成稳定的二进小波，存在快速的多尺度算法；而Canny算子不构成稳定的二进小波，无法给出快速的多尺度算法。

The problem of multi-objective usually meet many conflict each other and can not use the objective of the same standard unit, then to employ membership function of fuzzy theory,at first each objective function to change fuzzy set and express with membership function, membership function include the maximum constraint, minimum constraint, the decrease function of monotonic property, to become optimal of the multi-objective function, but still to scanty of weighting value with regard to adjustment of objective function, thus this thesis proposes the method of combine orthogonal arrays and particle swarm optimization to solve the problem of multi-objective optimal power flow, each objective function separately add weighting value, to setting each weighting value of objective function in order to the result of anticipating.

多目标最佳化的问题通常会面临到许多互相冲突且不能用同ㄧ标准单位的目标，於是利用模糊理论中的归属函数，首先将各目标函数转换成模糊集合并以归属函数表示，归属函数包含了最大限制值、最小限制值、单调的递减函数所组成，将各目标函数利用归属函数表示，形成单一目标函数的最佳化，但是仍缺乏权重值对於目标函数的调整，於是本篇论文提出ㄧ种权重值设定与粒子群优演算法的方法去解决多目标最佳电力潮流的问题，将各目标函上分别加上权重值设定各目标函数的权重值，得到预期的效果。

Since the multiple scattering should be considered, the scattering problem of many-cylinders is more complicated than single cylinder. By using scattering matrix method to solve the scattering problem of many-cylinders, first we have to express the incident fieldand scattered field by special function（for example, Bessel function and Hankel function）under cylindrical coordinate, then use the addition theorem of special function to get a linear system of equations to relate the incident field coefficients and scattered field coefficients. The incident and scattered field coefficients for every cylinder can be solved from the linear equations by matching electromagnetic boundary condition pointwisely.

单颗圆柱散射体的散射场解析解很早就被解出，而多个圆柱阵列的散射场问题因为涉及到入射光在圆柱与圆柱间的多重散射，故散射行为较单颗圆柱的散射复杂，因此圆柱阵列的多重散射问题需要利用加法定理来处理；散射矩阵法的主要精神即是先用圆柱座标下的特殊函数对平面波和圆柱散射体的内外域电磁场做无穷级数展开，再藉由特殊函数的加法定理将所有圆柱散射体的展开中心移到同一个展开中心，最后可以得到一组连结整个散射系统的入射电磁场系数及散射电磁场系数的线性方程组，将该组线性方程配合电磁场在散射体边界的连续条件，便可分别求出圆柱阵列中各个圆柱体的内部电磁场与外部散射场，再利用线性叠加原理即可求得整个圆柱系统的全域电磁场分布。

Trichogramma showed high control efficacy on cotton bollworm eggs after three times of release both in the second and in the third generation bollworm periods. The parasitism on the second and third generation bollworm eggs were 66.0%-70.7% and 76.0%-81.2%, respectively, which were significantly higher than that in the control (second generation: 7.0%-12.3%, third generation: 5.2%-7.4%). And the injury rate of cotton buds and bolls in the second and third generation bollworm were 2.2% and 3.1%, respectively, which were significantly lower than that in the control (second generation:8.5%, third generation: 20.9%). In the second generation bollworm period, number of bollworm eggs or larvae in the Trichogramma released cotton field did not differ to that in the chemically controlled field. But in the third generation, there were significantly less bollworm eggs and larvae in the Trichogramma released cotton field. There were more predators in the Trichogramma released cotton field. These results indicated that cotton boll worm in the transgenic insect-resistant cotton field can he effectively controlled by mass-releasing of T.

结果发现：棉铃虫卵在棉株不同部位的分布差异较大，2代棉铃虫卵主要分布在叶正面、叶背面和茎尖，3代棉铃虫卵主要分布于蕾铃；在放蜂田，赤眼蜂对棉株不同部位棉铃虫卵的寄生率差异较大，2，3代棉铃虫时期对叶正面、叫背面、茎尖、蕾铃的棉铃虫卵寄生率均较高，对叶柄和茎杆处卵的寄生率较低；并以3代棉铃虫时期的寄生率较高；在2，3代棉铃虫时期分别连续释放3次赤眼蜂，对棉铃虫具有很强控制作用，2，3代棉铃虫卵的被寄生率分别为66.0%~70.7%和76.0%~81.2%，均显著高于化防田的自然寄生率（2代：7.0%~12.3%，3代：5.2%~7.4%）；蕾铃被害率分别为2.2%和3.1%，均显著低于化防田（2代：8.5%，3代：20.9%；2代棉铃虫时期，放蜂田和化防田的棉铃虫卵量和幼虫数量差异均不显著，但3代棉铃虫以后，放蜂田棉铃虫卵量和幼虫数量均显著低于化防田，且放蜂田的捕食性天敌数量显著高于化防田。

Second, based on the spherical vector wave function in uniaxial anisotropic medium, and the first, second, third and fourth spherical Bessel functions satisfy the same differential equation and recursive formula. The scattering fields in terms of spherical vector wave function from a uniaxial anisotropic spherical shell and an anisotropic uniaxial-coated conducting sphere by a plane wave are derived. The electromagnetic fields in uniaxial anisotropic medium and free space can be expressed in terms of spherical vector wave functions in uniaxial anisotropic media and isotropic medium.

二、在建立均匀各向异性单轴介质球矢量波函数理论的基础上，利用二阶线性偏微分方程的性质和第一、第二、第三和第四类球Bessel函数满足相同的微分方程和递推关系，我们分别研究了单轴介质球壳和单轴介质涂覆导体球对平面波的电磁散射特性，首先给出了各个区域的电磁场用球矢量波函数来表示的解析表达式，进而利用电磁场在边界上满足电磁场切向连续的边界条件和球谐函数的正交性，得出了各向异性单轴介质球结构中电磁场用球矢量波函数表示的系数所满足的矩阵方程。

World War II: Battle of Saipan - Americans take Saipan.

1944年的今天，美国在塞班战役中拿下塞班岛。

When the scorner, the rejecter of truth, has become presumptuous; when the routine of work in the various money-making lines is carried on without regard to principle; when the student is eagerly seeking knowledge of everything but his Bible, Christ comes as a thief.{DA 635.3

当讥诮和拒绝真理的人，到了任意妄为时，当追求财利者罔顾按道义经营谋利时，当学人正在兢兢业业地研究各种知识，而单把圣经丢在一边时，基督要像贼一样来临。