查询词典 boundary line

We present a new direct boundary integral equation in terms of the boundary magnetic field only.

文中提出了一个新的直接边界积分公式，仅仅由边界上的已知磁场值确定空间点的磁场值。

Next, the boundary value problem is changed into an integral equation by applying a Green function. Then, by establishing a normalized boundary equation, the irregularity of the kernel of integral equation is overcome.

弹性扭转问题可看成是Poisson方程的边值问题，R 函数理论保证了对于任何复杂的区域，总可以找到一个规范化方程，从而可以将弹性扭转问题化为一个无奇异性的第二类Fredholm积分方程。

Based on a chosen normalized boundary equation, a new normalized boundary equation can be established such that the irregularity of the kernel of integral equations is overcame. Finally, natural frequency is obtained by the existence condition of nontrivial solution of the discrete algebraic equations derived from the integral equations.

边界方程有多种选择，在选定一种边界方程的基础上，可以通过建立一个新的边界方程来表示问题的边界，以克服积分核的奇异性；最后由积分方程的离散化方程组有非平凡解的条件，求得固有频率。

The research achievement are acquired as follows: 1From mathematical models for inverse scattering in two dimensional homogenous media including Dirichlet, Neumann, Robin,all kinds of probable mixed boundaries and cracks, direct and inverse scattering are discussed, and ill-posed integral equation and indicator function method are formulated for the diverse of boundary identification. It is shown that the kernel of the integral equation characters the boundary of scatterer, which is determined by solving it by virtual of regularity method, meanwhile, some numerical tests are given.

本研究取得了如下研究成果： 1）在二维均匀介质逆散射各种边界识别的数学模型（包括Dirichlet，Neumann，Robin，各种可能的混合边界问题，裂纹问题）下，分别考虑了正散射问题和逆散射问题，推导了上述各种边界识别的不适定积分方程以及指示函数方法，由于积分方程的核充分表征了散射物的边界，由此说明只要利用正则化方法求解该积分方程，就可以确定散射物的边界，并给出了一些数值实验。

A boundary integral formulation describing constant-αforce-free field with finite energycontent in the semi-infinite space above the sun was proposed(Yan,1995), this formulationcontains boundary field and its normal gradient under integral sign.

颜毅华1995年在太阳物理杂志上发表一文，就太阳磁场提出了一个具有有限能量的线性无力场模型，并对磁场给出了一个边界积分表示公式，该公式用边界上的已知磁场值和未知的磁场法向导数值来确定空间任意点的磁场值。

Firstly, by using the vector integral theory and boundary conditions of the electromagnetic filed, the boundary problem of two electromagnetic fields in the upper half space and lower half space is transformed into two vector integral equations just related to the topography interface, i.e.

提出了一种用边界元法计算频率域人工源三维地形电磁场的数值模拟方法。

In the hybrid algorithm, we use FEM to model the EM field in the interior domain, and then use the integral equation to compute the field on the boundary (to provide an artificial boundary condition for FEM system), and the finite element approximation is also convenient for deriving discrete equations of the integral equation.

混合法的原理是引入一个包围非均匀目标体的虚构边界，在边界内部的场用有限元法模拟，在边界外部的场用积分方程表达，二者在边界上通过场的连续性耦合起来。

It has been solved to deal with the boundary when using interpolation function method to evaluate boundary value problem.

解决了插值函数法的边界（以及求解区域内不同介质间分界线）处理问题，其结果已得到实际计算的验证。

Starting from the concept of Measured Equation of Invariance and the local equivalent theorem, it regarded the determination of the truncation boundary condition as a question of field simulation in a small area near the grid boundary. The practical disposal in the 2D and 3D cases was discussed.

基于测度不变方程的概念和局部等效原理，将截断边界条件的确定归结为网格边界上一小区域的电位场模拟问题，并讨论了在二维、三维情况下的具体处理。

Special attention should be paid when we apply the decomposition method to two-point boundary value problems, it is necessary to solve a algebraic system;It should be noted that a modification of inverse operator should be made when dealing with singular boundary value problems;Laplace transform and Pade approximants can be coupled to enhance the efficiency of the decomposition method.

比如，在求解两点边值问题时就需要特别注意，这时需要采用待定系数法，最后会涉及到系数方程组的求解；在处理奇异边值问题时需要重新定义逆运算；不少研究人员还把分解方法与Laplace变换和Padé逼近相结合来进一步提高分解方法的精度。

You can buy sweetened beverages, if that suits you.

你若喜欢的话，可以买些含有糖精的混合饮料。

As many of you are probably aware, Nick and Vanessa were recently faced with an embarrasing sex scandal after naked pictures of the two getting jiggy with it in a hot tub surfaced the net.

正如很多你可能知道，尼克和 Vanessa 最近面临一个尴尬的绯闻事件后，赤裸裸的图片两个越来越jiggy与它在浴缸中的一个热点浮现净。