查询词典 dirichlet boundary condition

In the numerical simulation of the wave equation, to develop an absorbing boundary condition in the finite domain is a very important problem.

在地震波传播的数值模拟中，在有限区域建立吸收边界条件是一个很重要的问题。

Stability, numerical dispersion and boundary condition are the several key problems in the seismic modeling.

稳定性，数值频散和边界是数值模拟中的关键性问题。

Keywords: Banach space;operator;equation;boundary condition;perturbation.

中文关键词：巴拿赫空间；算子；方程；边界条件；扰动

Paraxial approximation absorption boundary condition based on acoustic wave equation can obtain better absorption results by increasing paraxial approximation order of Taylor series. However, this kind of operation will increase the complexity of difference computation, and result in instability of computation process.

基于声波波动方程的旁轴近似吸收边界条件可以通过提高泰勒级数展开的旁轴近似阶数获得更好的吸收效果，但这样不仅增加了差分计算的复杂性，同时还导致计算过程不稳定。

On the ship body, the parabolic curve panels are adopted to discretize the surface in order to improve the continuity and the linearly variable sources are distributed on panels. The solid boundary condition is satisfied rigidly on the curve panel.

在船体上，本文采用了二阶抛物面单元离散船休表面，以改善用平面单元离散时出现的不连续，并在单元上布置强度呈线性分布的源汇，固面条件在曲面单元上严格满足。

Secondly, point out that meshless method is different from finite element method in handling boundary condition and numerical integral because the approximation function of meshless method is not inserted function, it have itself special methods. Deduces meshless Galerkin essential equation of parabolic partial differential equation with the method ofweighted residuals------Galerkin. Furthermore, discusses the main factors which may effectthe calculation precision and give some suggestion with which can get the best result.

其次，由于无网格法的近似函数不是插值函数，所以无网格Galerkin法在处理边界条件和对区域积分时是不同于有限元的，它有其独特的处理方法，从加权残量法——Galerkin出发，推导出抛物型偏微分方程无网格Galerkin法的基本方程，并对影响无网格Galerkin法的主要因素进行探讨，给出了取得最佳效果的相应建议。

And boundary condition and parametrization of offset data points influencing on interpolating curve is discussed.

因此，正确地选择边界条件和型值点的参数化方法将会得到所需要的插值曲线。

The method is easily realized with small computation amount,and its absorption effect is better than conventional paraxial approximation absorption boundary condition.

该方法简单易行，计算量小，而吸收效果比常规旁轴近似吸收边界条件更好。

Therefore,it is necessary to research diffusion equation for suspended sediment because it describes the sediment move process in the water body.The equation is a various coefficients second-order linear partial differential equa-tion,such equation under complex boundary condition is very difficult to get its analytical solution,while its numerical solution relative analytical solution is more easier and has the obvious superiority:simple,the computation convenience.but to get a kind of difference format which is good accuracy and stability is not easy.

泥沙扩散方程实际上是一个变系数的二阶线性偏微分方程，这样的方程在各种复杂边界条件下求解是十分困难的，求它的解析解在数学上存在着难以克服的障碍，无法求出其精确解，因此常用数值方法求它的近似解，相比较而言，数值方法有着明显的优势：即简单灵活、计算方便快捷，但要寻找一种精度高、稳定性好、计算方便的差分格式也并非易事。

Numerical results for perfectly conduction and homogeneous penetrable circular cylinder are presented and compared with the solutions by using second-order differential operator B2 type absorbing boundary condition.

本文使用这种边界条件对理想导电及均匀电磁可穿透材料圆柱散射体的表面场进行了数值计算，并与使用二阶微分算子B_2型的吸收边界条件的结果作了比较。

The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn't be stripped along myofibrillar trajectory since they were prone to break because of their friability.

组2的心脏解剖困难，表现为纤维组织坚韧，游离肺动脉非常困难；徒手无法松解左、右纤维三角，肺动脉和主动脉根部的游离非常困难；心肌纤维坚硬、质脆，解剖时容易断离成碎块，无法沿纤维走行方向剥离。

We have battled against the odds in a province that has become increasingly violent.

我们对在一个争夺日益激烈省的可能性。