查询词典 geometric difference equation

Differential equations and difference equations are powerful tools that describe the law of nature, but it is difficult to find their general solutions. Therefore , there has been an increasing interest in the study of the nature of solutions of differential equation and difference equation in theory.

微分方程及差分方程是用来描述自然现象变化规律的一种有力工具，由于寻求其通解十分困难，故从理论上探讨解的性态一直是近年来研究的热点问题。

Through the limit difference method,the partial differential equation of the semiconductor device is transformed into a difference equation,and the corresponding boundary condition is discretized with high accuracy.

采用有限差分法把器件工作的偏微分方程转化为差分方程，并将相应的边界条件转化为精度较高的离散化形式。

It is known theoretically that to the variational problem with weak constraints in cost functional J, its Euler equation can be discreted into difference format, by using matrix theory and difference method of partial differential equation we know that there exists optimal selection of weight factors in the cost functional under the condition of minimal variance between analysis field and ideal field.

从理论上可知，对于目标泛函J带有约束条件的变分问题，将其Euler方程离散成差分形式，利用矩阵理论和偏微分方程的差分方法，则目标泛函的权重因子，在分析场和理想场的最小方差意义下存在最优选取。

Because the equation is a various coefficients second-order parabolical partial differential equation,explicit difference formats usually have high condition for stability. Implicit difference formats have good stability,but they must calculate a set of algebraic equations,which are too complex.

由于泥沙扩散方程是一个二维变系数的抛物型方程，对于多维的方程，显格式往往稳定性要求很高，而隐格式虽然稳定性较好，但它要解大型的代数方程组，工作量也非常大，为了克服这两种格式的不足，常用ADI法求解，但仍存在一些计算量偏大等不足之处，因此构造出更好的差分格式是有必要的。

This model used the finite—difference approximation to the advection— dispersion equation. The spatial derivatives in the flow equation are approximated by central difference written about grid—block boundaries and time derivatives are approximated by a fully implicit backward scheme.

水流方程的空间导数采用中心差分格式离散，时间导数采用隐式差分格式离散，建立了土壤水分和污染物在各种饱和度的条件下迁移转化方程耦合求解的二维数值计算模型。

The input - output relationship of any linear time-invariant discrete system can be described by a difference equation The complete solution of a linear difference equation consists of two parts: the free component and the forced component.

任何一个线性时不变离散系统的输入输出关系都可用线性差分方程式来描写。差分方程式的解答包括两部分：即自由分量和强制分量。

In this paper, the author is concerned with the problems that are to be solved in the field of Partial Difference Equations such as the following: the existence of oscillatory solutions of some partial difference equation, the asymptotic behavior of positive solutions of the same equation.

本文旨在研究当前偏差分方程领域中尚待解决的有关振动解的存在性及正解的渐近存在性等问题。

In this paper difference equation of motion fr om one point to another point on the earth is derived from the geodesic equation on the earth and spherical trigonometry formulas. Some difference track formul as of a maneuvering object are also given.

以大地椭球三角形模型为基础，利用地球表面二点间最短路径的大地线方程和球面三角形的有关公式，建立了由地球表面一点运动到另一点的差分运动方程，同时也给出了在进行航向机动时的差分运动轨迹。

By considering higher orderapproximation to interaural phase difference,a moregeneral localization equation(which is applicable to f＜1.4kHz)is derived,and the localization equation forstereo sound image with interchannel phase difference isalso given.

并且提出了重发通路间存在相位差时的立体声声像定位公式。

A concept, shadow equation, was put forward to search the real geometric meaning of complex roots for general equation.

提出了影像方程的概念，从而可以研究一般方程复数解在实平面上的几何意义。

I was just taking her hand, to help her out of a car, and I knew it.

我只是握着她的手，扶她下车，但我知道这一切。

China and South Korea have excoriated Japan over its approval of new school books which they say whitewash the atrocities committed during Japanese occupation, and anti-Japanese protests have been held in Chinese cities. The lingering bitterness over Japan's past imperialism still threatens to mar relations between the big East Asian powers

中国和韩国强烈谴责日本通过新的中学历史教科书，他们认为这一教科书掩盖了日本在其占领期间所犯下的残酷暴行，反日抗议活动在中国数座城市发生，历史上日本帝国主义制造的痛楚无法被忘却，这有可能破坏东亚强国间的关系。