查询词典 anomalous scattering

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。

Based on the research on the scattering of the Gaussian beam from single sphere, the intensity distributions of LGB beam in different propagation distance is analyzed. Without considering the relationship of scattering and phase shift, the beam coefficients is gained by the solution of scattering cross section, and the LGB is expanded in terms of the vector spherical harmonics as fundamental Gaussian beam. The scattering of the beam with orbital angular momentum from single sphere located on the propagation axis is studied.

在单体球粒子对高斯光束散射研究的基础上，分析了在自由空间不同传输距离LGB光束的光强分布情况，在不考虑散射和波束相移关系的情况下，将LGB作为入射高斯光束，通过对波束入射时的散射衰减截面求解得到波束因子，利用矢量球谐函数对入射高斯波束进行展开，从而研究了单球粒子在在轴条件下对具轨道角动量高斯波束入射的散射问题。

But using infrared CCD, which has little scattering light, strong penetration ability, can improve image quality greatly. This paper analyzes the effects on surveillance by Rayleigh scattering, Mie scattering and unselective scattering theoretically. In addition it discusses the relation between transmission coefficient, reflection coefficient and wavelength of infrared CCD.

而采用散射光小，穿透能力强的红外CCD，则可以显著改善图象质量，从理论上分析了Rayleigh散射，Mie散射，无选择散射对监测的影响，讨论了红外波段CCD的反射系数、透射系数与波长的关系。

Some methods to restrain reverberation are developed. Three scattering models(bottom scattering, surface scattering and volume scattering model) in bistatic sonars are developed and simulated.

重点研究了双基地声纳的各种散射模型(海底散射模型、海面散射模型、体积散射模型)，通过对各种影响因素的分析，给出了各种模型的明确表达式，并对模型进行了仿真分析。

The results of the simulation analysis and experiments indicate that the loss of ultraviolet scattering transmission in atmosphere is high because of the particle scattering and absorbing in solar-blind zone; that is, the received power can descend 20 dB with the distance increasing 10 times. Therefore, the ultraviolet scattering is fit for short range communication. In short range, the pulse extension due to scattering is at microsecond order and its influence for low and moderate bit rate communication systems is weak. Since the light output power of a single ultraviolet LED is low, a multi-LED array can be used to increase the transmit power and extend the communication range.

仿真分析与实验结果显示：日盲区紫外光在大气中散射传输时由于大气粒子的强烈散射与吸收，传输损耗较大，距离每增加10倍，接收功率下降20dB，因此日盲区紫外光大气散射通信适用于近距离通信场合；近距离传输时散射造成的光脉冲多径展宽为微秒量级，对中低速通信系统影响较小；单个紫外LED发光功率较低，可通过多个LED阵列来提高发射功率，增大通信距离。

Scattering characteristics are studied of inhomogeneous cylinders immersed in an absorbing medium illuminated normally by plane waves. Scattering and extinction cross sections are derived, and the efficient algorithm is presented. Scattering matrix is simulated and discussed.

系统地解决了吸收介质中非均匀柱粒子对垂直入射平面波的散射问题，包括散射场、散射截面、消光截面的解析解，提出了快速、有效的计算方法；数值模拟了均匀、非均匀圆柱的散射矩阵，并与已有文献发表结果对比。

Basing on the Graf′s addition theorem, two expessions, interior and exterior expression, are deduced and the suitable problems for them are discussed. It has been found that the interior expression is the main point for sovling the scattering problem of circular inclusion in half-space. It also has been found that the exterior expression is the key for the scattering problem of circular arc canyon and circular arc alluvial valley, and is one of the main points for scattering problem of circular arc hill as well.

从Graf原有加法公式出发，本文给出了其内域型和外域型两种表达形式并讨论了这两种表达的适用范围，同时指出：内域型表达是求解半空间内含夹塞区出平面散射问题的要点，而外域型表达是解决任意圆弧型凹陷地形和任意圆弧型沉积盆地出平面散射问题中求解难点的关键，同时也是克服任意圆弧型凸起地形出平面散射问题求解困难的要点之一。

The Airy function is used to calculate the plasma impedance and the grill-plasma scattering matrix is deduced, then the coupling properties of the HT-7 LHCD MJ launcher are studied with the antenna scattering matrix and the grill-plasma scattering matrix based on the liner coupling theory. The average power reflection coefficient, directivity, power spectrum are obtained for different edge plasma densities and for different phasings between main waveguides.

采用线型耦合理论，用艾黎函数计算了等离子体阻抗，推导出常规波导阵对等离子体的散射矩阵，并利用它和天线自身的散射矩阵研究了HT-7装置低杂波多结波导阵天线的耦合特性；计算了其平均功率反射系数、方向性系数和功率谱与等离子体边缘密度和主波导相位差等参数的关系。

The angular distribution of the bistaticscattering coefficient of HH polarization were obtained by numerical implementation. Influences of the permittivity and the mean layer thickness of intermediate medium, friction velocity and the frequency of the incident wave on the bistatic scattering coefficient were discussed. The basic characteristics, the zonal characteristics and the characteristics with varying of frequency of the scattering coefficient from stratified sea surface were obtained. The numerical results show that the scattering coefficient has approximate "quantization" characteristics.

通过数值计算得到了HH 极化双站散射系数随散射角的变化曲线，讨论了中间介质介电常数和厚度、摩擦风速和入射波频率对双站散射系数的影响，得到改进的一维分形分层海面散射系数的基本特征、分区特征和随频率变化的特征，结果表明散射系数近似具有"量子化"特征。

In this paper, firstly we researched the relationships of the communicating distanceand the channel characteristic, the effect of the multiple scattering to the laserpropagation, the requirement of the laser communication to the ATP system and theway to determine the angular dispersion and receive field of view. It is proved that inlight haze weather, letting the input and output laser\'s wavelength are diferrent witheach other, after passing by the filter, it can avoid backward scattering effectually andfor the communication within 15km, the influence of the multiple scattering inatmosphere can be ignored.

论文对通信距离与信道特性、多次散射对光传输的影响、无线激光通信对ATP带宽的需求以及光束发散角和接收视场角等重要系统性能参数和指标进行了分析和研究，证明了在轻霾天气状态下，使系统中两终端发送的激光束波长各不相同，经过光束滤波，可以有效地消除后向散射干扰；在15km的通信距离范围内，大气中的多次散射对无线激光通信光传输的影响可以忽略。

But this is impossible, as long as it is engaging in a market economy, there are risks in any operation.

但是，这是不可能的，只要是搞市场经济，是有风险的任何行动。

We're on the same wavelength.

我们是同道中人。