查询词典 dirichlet conditions

The result shows that the mixed boundary condition can greatly reduce the calculation area without affecting accuracy of the solution.It is followed by the higher accuracy of Dirichlet boundary condition which makes the boundary error greater when measured points is near the boundary, so we must take a sufficiently large border region.The homogeneous boundary condition has relatively large error, but the use of non-triangle poles devices makes apparent resistivity calculation error become small, because of elimination of the effect on potential difference for the infinite boundary. In inversion, in order to save computing time, homogeneous boundary conditions are often used to perform finite element forward calculation.

结果表明，混合边界条件精度最高，可大大缩小求解区域而不影响计算精度，其次是Dirichlet边界条件精度较高，但测点越靠边界误差会越大，必须取足够大的边界区域，齐次边界条件的误差比较大，但如果采用非二极装置，通过电位差计算得到的视电阻率，由于无穷远边界对电位差的影响基本消除，视电阻率计算误差与混合边界条件下的接近，在反演中，为了节省计算时间，经常使用齐次边界条件进行有限元正演。

What differ from that of the researchers in the past is the consideration of the direction of Hopf bifurcation with Dirichlet boundary condition , that is, the conditions when the Hopf bifurcation periodic solutions are orbitally asymptotically stable with asymptotic phase.Our basic idea come from the results given by Tang[30]. We adopt the method used by Hassard in the Hopf bifurcation theorem in [24], which is to judge the existence and the direction of Hopf bifurcation, and the stability of the Hopf bifurcation periodic solutions.

与以前的研究者不同的是，本文不仅讨论了在Dirichlet边界条件下系统的Hopf分支在以扩散系数为分支参数的情况下的存在性和分支周期解的空间非齐次性，而且更多的关注了系统在Dirichlet边界条件下Hopf分支解的稳定性及Hopf分支的方向，也即系统定态解在何种条件下，当分支参数如何变化时产生Hopf分支且分支周期解是带渐近位相轨道渐近稳定的。

In part two, this thesis is dealt with properties of solutions to a degenerate parabolic system coupled via non-local sources, subject to homogeneous Dirichlet conditions and nonnegative initial data.

第二部分，讨论了一类具有齐次Dirichlet边界条件和非负初值的非局部源耦合的退化抛物系统的第一初边值问题。

When there are diffusion effects and Dirichlet boundary conditions, we firstly obtain the conditions such that the system exists positive equilibrium solutions and give the asymptotic expression of these positive equilibrium solutions.

在具有扩散影响和Dirichlet边界条件时，首先利用隐含数定理获得了系统存在正平衡解的条件和正平衡解的渐近表达式。

The boundary conditions are assumed to be either the Dirichlet condition or linear Robin conditions.

在第一章，我们应用上、下解方法，bootstrap技巧和Schauder不动点定理考察如下三类周期反应扩散方程组的周期稳态解的存在性和一般的时变解的渐近性态：（1）拟单增系统；（2）混拟单调系统；（3）一个非拟单调2-系统，其边界条件是Dirichlet条件或线性Robin条件。

In Chapter 1, we use the upper and lower solutions method, the bootstrap technique and the Schauder fixed point theorem to investigate the existence of periodic solutions and the asymptotic behavior of general time-dependent solutions for periodic reaction-diffusion systems of the following three types:(1) Quasimonotone nondecreasing system;(2) Mixed quasimonotone system;(3) A nonquasimonotone 2-system. The boundary conditions are assumed to be either the Dirichlet condition or linear Robin conditions.

在第一章，我们应用上、下解方法，bootstrap技巧和Schauder不动点定理考察如下三类周期反应扩散方程组的周期稳态解的存在性和一般的时变解的渐近性态：（1）拟单增系统；（2）混拟单调系统；（3）一个非拟单调2-系统，其边界条件是Dirichlet条件或线性Robin条件。

Apparently, the approximate controllability doesn"t hold for generally linear parabolic equations with bounded control. It doesn"t hold for the semilinear heat equations presented there,either. Then, it is proved by analyzing its" solutions that no matter how long the time T is , there are targets that can"t be approximated by the solution of heat equation with Dirichlet boundary conditions;If a given target satisying certain conditions can be reached by the solution of heat equation .

本文先针对两个具体的半线性热方程系统证明了控制加约束后系统是不能控的；然后通过分析方程的解，对带位势及Dirichlet边界条件的热方程系统，无论时间多大，都存在不能控的目标；文中还证明了满足一定条件的目标可达。

In Chapter 1, the present conditions of numerical methods for the Dirichlet problem, the probability theory which connects with the Dirichlet problem, and the essence and characteristics of the probabilistic numerical method are summarized.

第一章综述了Dirichlet问题数值解的现状、与Dirichlet问题密切联系的概率理论以及概率数值方法的实质和特点。

The classical overlapping Schwarz methods try to transport boundary information by exchanging message on the artificial boundaries. However because of taking Dirichlet conditions as the transmission conditions, which makes the solution reflect when across the artificial boundaries, classical overlapping Schwarz methods converge very slowly—suppose the overlapping domains take a little percentage.

人们很早就认识到，在Schwarz方法中可以采用其它的内边界条件—如Robin条件来代替Dirichlet内边界条件，而且也注意到如果参数选取合适，那么这些内边界条件可以大大加快Schwarz方法的收敛速度。

Chapter 2 investigates the convergence of triple and n -ple Dirichlet series, the convergence of triple random Dirichlet series under certain conditions, and the convergence of double bi-random Dirichlet series under the conditionand obtains some results similar to double Dirichlet series.

此外还在条件 sum from m=1 to +∞ sum from n=0 to +∞ P{|X_|≥m~pn~p}＜+∞下，研究了二重双随机Dirichlet级数的收敛性，得到了一些类似于二重Dirichlet级数的有关结论。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

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