查询词典 boundary value problem

Remove row and column' and 'put a big number' have been used for the first boundary;a continuous Regional Identification Function is used on the basis of non-variant nodal virtual flux method for the free surface boundary;Gauss formula is used to make the curved surface integral of the free surface boundary transformed as the difference between volumn integral and other curved surface integral to calculate the integral item on boundaries, which avoiding finding the position of free surface, while the continuous Regional Identification Function is applied to calculate volumn integral and surface integral;Crout and PCG method is used for solusion.

对于已知水头边界，采用&去行去列法&和&置大数法&进行处理；对于自由面穿过的单元，在固定网格节点虚流量法的基础上，引入连续的区域识别函数；对于非稳定渗流中自由面边界积分项，采用高斯公式将求自由面的面积分转化为求体积分与其他面积分之差，避免了求自由面的具体位置，同时在计算体积分和面积分时采用连续的区域识别函数；在解法上，采用直接解法和PCG法。

After comparing with many techniques available for dealing with the open boundary problems, the asymptotic boundary conditions combined with the finite element method are employed for the calculation of 3-D open boundary magnetic fields in ironless PM motor.

根据对各种开域电磁场计算方法的分析比较，本文将渐近边界条件法和有限元法结合解决无铁心永磁电机三维开域磁场计算问题。

However, such tidal overheight is often ignored in the current regional numerical simulation due to intensive computational requirement. Only the mean sea level is used as the fixed seaward boundary, which may wrongly predict the groundwater table position. Therefore, we aim to determine an equivalent seaward boundary through numerical modeling. The equivalent seaward boundary takes into account the tide-induced overheight effects.

然而，由于潮汐动边界处理的复杂性而导致巨大的计算量，在现有的区域地下水数学模型中，潮汐引起的海平面波动通常被忽略，仅仅以平均海平面高度作为模型的海岸边界条件，其预测出的地下水水位位置与实际情况可能会有一定的误差。

A simplified model was proposed to simulate material microstructure according that metal solidification is a Monte Carlo process. First, use the point of"putting randomly, growing uniformly"to generate grain boundary, then recognize grain boundary trifurcate points, eliminate bad trifurcate points, and distinguish the connections among these points, thus obtain straight grain boundary picture.

根据金属凝固过程是—Monte Carlo过程，建立了金属材料显微组织的简化Monte Carlo方法，采用&随机投放，等速生长&的方法形成矩齿形晶界图，并通过逐点判断法识别出晶界三重点，剔除奇异三重点，并识别出晶界及晶界间相邻关系，从而获得晶界结构的直线近似形态图，为细观组织短裂纹的数值模拟作好准备。

With that point in mind we review here some advances in the classical boundary layer, multilayer boundary layer, interacting boundary layer and diffusion parabolized NS equations theories and corresponding algorithms and applications.

以此为线索，简要评述经典边界层、多层边界层、干扰边界层、扩散抛物化 NS方程诸理论、相应算法和应用的若干研究进展；诸理论之间以及他们与实验的关系；简化湍流计算的一点注释以及物理分析和数值模拟相结合的一些问题。

The results show that the relationship betweentotal potential energy and time step exhibits periodic characteristic when sigma-3symmetric twist grain boundary model and sigma-3 tilt grain boundary model slide atOK. But for sigma-13 asymmetric tilt grain boundary, the relationship between totalpotential energy and time step exhibits damp surge characteristic.

结果发现，∑3对称扭转晶界模型与∑3对称倾侧晶界模型在0K滑动时，系统的势能与计算步数之间的关系曲线呈现周期性变化的规律，而∑13非对称倾侧晶界模型系统的势能与计算步数之间的关系却呈现阻尼振荡特征的变化规律。

The spring part of this boundary can be determined by Mindlin equations, and frequency dependent viscous material (resistance proportional to velocity) is introduced into the boundary dements to simulate dashpots of the viscous boundary.

提出一种能用于无限域地基动、静力有限元分析的简单人工边界-粘弹边界，采用一层边界单元来实现。

The apparent selective establishment criteria of the new strips may explain the low similarity in species composition between the original boundary and the new boundary plots: only non-woodland perennial monocots and dicots had high establishment rates in the herbaceous strips in all boundary types.

表观选择性建立标准的新带可以解释低，在相似的物种组成与原选区分界及新的边界情节：只有非林地多年生monocots和双子叶植物有较高的建立利率，在绿草带的所有边界类型。

Orientation method for the determination of grain boundary character distribution, single section trace method for the analysis of low??index grain boundary plane and five parameter method for the measurement of grain boundary plane character distribution are discussed significantly.

重点讨论了基于EBSD技术的晶界特征分布测定取向差法、低指数晶界面测定单一截面迹线法和晶界面特征分布测定五参数法。

In Chapter 4, the Thwaites＇s method for 2-D laminar boundary layer and the Truckenbrodt＇s method for 2-D turbulent boundary layer are developed to solve the"quasi-3-D"equations for the 3-D boundary layers on rotating helical blades, and a integral method, which can be solved by iteration, is resulted.

在第4章中，计算二维层流边界层的Thwaites方法和计算二维湍流边界层的Truckenbrodt方法被推广用以解关于旋转螺旋面上三维边界层的&准三维&方程，得到一种可迭代求解的积分方法。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。