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A Gaussian beam is expanded intothe sum over a set of plane waves with the aid of the plane-wave spectrumtechnique.

文中应用电磁散射理论重点分析亚毫米高斯波通过金属栅网的散射特性，通过数值计算、仿真及实验测量分析金属栅网的近场散射特性。

Based on the method that a rectangular function can be expanded into a sum of complex Gaussian functions with finite numbers, the propagation characteristics of a Gaussian beam passing through apertured spatial filter systems are analysed and the corresponding analytical formulae are obtained respectively.

根据矩形函数可以展开为有限复高斯函数之和的方法，从柯林斯衍射积分公式出发，对高斯光束通过受限空间滤波器传输特性进行分析，得到了相应的近似解析式。利用Matlab对其解析式进行数值模拟，得出一组直观的结果。

In this paper, by using the method of expanding the hard-edge aperture function into a finite sum of complex Gaussian functions, the recurrence propagation expression for the propagation of partially coherent beams through a multiple apertured ABCD optical system is derived, which provides a fast algorithm for simulating the propagation of partially coherent beams through hard-aperture optics.

用有限个复高斯函数之和来逼近硬边光阑窗函数的方法，推导出了部分相干光通过多个硬边光阑ABCD光学系统传输的递推公式，提供了一种模拟部分相干光通过硬边光学系统传输的快速算法。

Base on the fact that a hard-edge aperture function can be expanded into a finite sum of complex Gaussian functions, the approximate analytical expressions for the propagation characters of Hermite-Guassian beams passing through double rectangular apertured are derived. The approximate analysis uses Collins formula. At last, Matlab illustrates some numerical examples.

基于硬边孔函数能拓展成一组有限复高斯函数的和，研究厄米－高斯光束通过双矩孔的传输特性，用Collins公式分析，用Matlab进行一些数值模拟。

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。

The expansion coefficients Of aperture fields are Obtained after the three-dimensional arbitrary aperture fields have been represented by the sum of three-dimensional Gaussian function in the configuration-spatial wavenumber phase space.

本文利用Gabor原理把三维任意口面场表示成离散结构－波数相位空间中三维高斯基函数的叠加，将二维高斯基函数与相位空间谱双重正交的函数推广到三维，从而得到口面场展开函数。

The propagation equations for oblique and off-axial Gaussian beams passing through cat-eye optical lens are deduced by using the theory of matrix optics and expanding the aperture function into a finite sum of complex Gaussian functions.

运用矩阵光学理论以及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，进一步推导了倾斜离轴高斯光束通过猫眼光学镜头的解析传输公式，通过数值计算分析得到了倾斜系数和离轴量对猫眼效应反射光光强分布的影响规律。

Using the relations between Hermite and Laguerre-Gaussian modes and expanding the window function of two-dimensional rectangular hard-edged apertures into a finite sum of complex Gaussian functions, the propagation of complex- argument Laguerre-Gaussian beams through a paraxial optical ABCD system with a rectangular hard-edged aperture is studied. An analytical propagation equation is derived and used to study the diffraction at the rectangular hard-edged aperture and the focusing properties of complex-argument LG beams.

利用拉盖尔－高斯模和厄米－高斯模的变换公式，并使用将二维矩孔光阑窗口函数展开为有限个复高斯函数之和的方法，得到了复宗量拉盖尔－高斯光束通过含矩形硬边光阑近轴ABCD光学系统的变换的解析传输公式，并对复宗量LG光束通过矩形硬边光阑的衍射和聚焦特性进行了研究。

Surface ozone data of Mauna Loa and the other 14 monitoring sites of altitude lower than 1000 m in the northern hemisphere were used to give a joint discussion for the distribution and variation features of surface O3. The data, based on ground observation, were collected, processed, and distributed by WDCGG (World Data Centre for Greenhouse Gases) in GAW. The monthly mean and hourly data of surface ozone in these 15 sites were analyzed to sum up the difference of surface ozone annual and seasonal variations in different areas of the northern hemisphere.

利用来自GAW（Global Atmosphere Watch，全球大气监测）的、由WDCGG World Data Centre for Greenhouse Gases，世界温室气体数据中心）收集整理和发布的、基于地基观测的北半球共15个站点的地面O3含量的逐月观测资料以及逐时观测资料，分析、对比并总结了北半球不同经纬度各区域的地面O3含量的年变化和各个季节的日变化规律。

New type of fuzzy clustering model, based on least sum of entropy and generalized distance of weight, has been put forward. Weight of indexes is considered in the model.

4提出了基于模糊熵及权广义距离之和最小的新型的模糊聚类模型，该模型考虑了指标的权重。

Do not gum up the work by telling mother what we are going to do .

别告诉母亲我们要干的事，那会把事情搞糟的。

In recent years, application of the partial prestressed concrete beam s is developed.

近年来，随着部分预应力砼梁应用的推广，发现我国规范所采用的名义拉应力法的计算结果不稳定。