矢函数

It is shown that the expression of electric-type dyadic Green's function is the sum of an eigen-mode expansion containing nine dyadic components and a singular term.

得到的电型并矢格林函数表达式由包括九个并矢分量的本征模展开式和一个奇异项组成。

It is hard to draw in two dimensions a picture of a vector function in three-dimensional space.

在两维图上画三维空间的矢函数图形是件难事。

A series of theoretical and experimental studies on the microstrip patch antennas with dielectric superstrates is carried out systematically. Firstly, a comprehensive survey of the microstrip antenna technology and its theories are presented. Then, two analysis techniques, named as the spectral domain Green's function method and the spectral domain integral equation method are developed. The SDGF method is a simplified analysis technique, which takes advantage of the spectral domain immittance approach to find the dyadic Green's function for the stratified media, and obtains the complete closed-form formulas for radiation patterns, directivity, efficiency, gain etc. Some interesting calculated results are presented. The SDIE method is capable of determining resonant frequency, radiation characteristics, input impedance etc, for the covered microstrip patch antennas. Comparing with other full-wave analyses it reduced computation and mathematical labour remarkably. The singularities near the pole location of the surface-wave modes and the difficulty of the integral computation over infinite range of oscillating integrands are dealt with actively and documented well. Results predicted by the SDIE method agree extremely well with our experimental results for resonant frequencies of various superstrates. The superstrate effects on impedance and radiation characteristics also have been investigated experimentally so that the gap due to lack of measured data and computed results for multi-layered superstrate has been filled to some degrees and two useful observations have been achieved for weakening the resonant frequency shift and optimizing the microstrip antenna gain. As a meaningful application, the design and analysis of a 4×4 patch array are introduced.

实用微带天线普遍加介质覆盖层来防护热，物理损伤和环境影响，也可能在飞行或严酷气候条件下自然形成覆盖层本论文对带介质覆盖层的微带贴片天线系统地作了一系列理论和实验研究首先，对微带天线技术和理论作了全面的综述然后，发展了两种分析方法，称为谱域格林函数法和谱域积分方程法SDGF法是一种简化的分析技术，它利用谱域导抗法来求得分层媒质的并矢格林函数，并得出方向图、方向性系数、增益等参数的完整的闭式公式，给出了一些令人感兴趣的计算结果SDIE法能确定介质覆盖微带天线的谐振频率、辐射特性和输入阻抗等与其它全波分析方法相比，它明显减小了计算量和数学工作量已有效地处理了表面波模极点附近的奇异性和对振荡的被积函数的无限区间积分计算的困难对于不同覆盖层情况下的谐振频率，由SDIE法所预示的结果与我们的实验结果吻合得很好对于覆盖层对阻抗和辐射特性的影响也已作了实验研究这在某种程度上填补了缺少实验数据和计算结果之间的间隙，并得出了缓解谐振频率偏移和优化天线增益的两点有用的结论作为有意义的应用，介绍了一个4×4元矩形贴片天线阵的设计和分析。

Substitute surface conception was introduced in the tolerance modeling. Intrinsic deviation between the substitute surface and the theoretical surface was described by vector function on the basis of the vector parametric representation of the theoretical surface.

引入替代表面的概念，基于理论表面矢量参数化表示，用矢函数来描述替代表面和理论表面之间的本质特征偏差。

A convergence acceleration technique based on functional asymptotic expansion and Poisson's summation formula is developed to raise the calculation efficiency of waveguide dyadic Green's functions which are expanded in infinite series.

为此，作者提出"谱展开边界元法"，以求解波导外空间的并矢Green函数；引入边界元法以求解波导壁内折曲缝隙腔的并矢Green函数；并研究了无穷级数的逐级加速收敛变换，以解决波导中Green函数的计算问题。

For acquiring relations between the eigenfunctions of waveguides and tensor Green function, we first take the Fourier transform of Green function. In isotropic media the simplest image function can be expressed in dyadic form, and in anisotropic media in the form of ABA+-ikz0,where A is the coordinate matrix.

为了得到波导管的本征函数和格林张量函数的一些关系，我们首先对格林函数作富氏变换，它的象函数在各向同性介质波导中以并矢形式作为最简单的表达方法，而在充有各向异性介质波导中可以表为ABA~+e~的形式，这里A是坐标矩阵。

By using this method, the boundary value problem of vector wave equation can be transformed Into two independent boundary value problems of scalar wave equations and other two additional vector differentia! operations.

用这种方法可以很方便地求解所有现在用并矢格林函数的本征展开法所能求得的各种并矢格林函数。

3D-CTM (Coupled Thermo-Mechanical Forming Simulation) software for precision forging process of aero-engine blade was developed. The key technologies of 3D coupled rigid-viscoplastic thermo-mechanical FEM simulation of blade forging process were studied systematically. By using the remeshing method of contracting from the boundary to the inner, new mesh system from old distorted mesh system can be obtained. A method of modifying the position of nodes touching on the die according to its original normal was proposed to avoid "dead lock" problem due to uncontinuity of normal of scatted die meshes. The pseudo-static iterative algorithm was used to simplify the coupled thermo-mechanical computation. In particular, formulations to determine relaxation factor β was established for rigid viscoplastic FEM adopting penalty function method, and an improved cubic factor rapid algorithm derived from these formulations was proposed by combining with the advantage of advance and retreat search method.

采用基于边界构形的内缩法，实现了三维畸变网格的重新划分；提出了初矢修正法对触模节点的位置进行修正，解决了由于离散的模具网格的法矢不连续造成的&死锁&问题；采用准静态迭代法简化了速度场和温度场耦合计算过程；特别是针对减速因子β的选取，建立了适用于三维复杂成形过程刚粘塑性罚函数法有限元三次因子法的计算公式，并结合进退搜索法提出了改进的三次因子快速算法，提高了模拟计算效率和稳定性，在此基础之上，开发了面向叶片精锻过程的三维刚粘塑性热力耦合有限元模拟分析系统(3D-CTM)，系统的可靠性得到了圆柱体镦粗的验证。

For the dyadic Green's function, we have the constituent method, source dyadic method and the quasi source dyadic method.

对于并矢格林函数奇异性问题处理方法有：分量处理法、源并矢法和拟源并矢法等处理方法。

A recursive matrix method is adopted for computing the magnetic-current-source dyadic Green′s function in anisotropic media. The response of multi-component induction logging in layered and deviated anisotropic formation is simulated by using the obtained dyadic Green′s function. The influence of coil spacing, bed thickness, deviation angle and shoulder bed on the response is analyzed.

采用递推矩阵方法计算各向异性介质的磁流源并矢Green函数，并利用上述并矢Green函数对层状各向异性倾斜地层中多分量感应测井的响应进行数值模拟，分析了线圈距、层厚、倾角和围岩对多分量感应测井响应的影响。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。