查询词典 difference differential equation

Firstly,the differential equation with parameters is given,at the same time,in order to let the truncation error of differential equation reach O(Δt~2+Δx~4) as high as possible,the method of undetermined coefficent is used to appropriately select the expression of these parameters.Secondly,the stability condition of the scheme derived is given by using the Fourier method of stability analysi...

首先给出了含参变量的差分方程，并用待定系数法适当地选取了这些参数的表示式，以使差分方程的截断误差阶尽可能高地达到了O(Δt2+Δx4)；其次用稳定性分析的Fourier方法给出了所得格式的稳定性条件；然后给出了确定差分格式中参数的两种方法，得到了一个稳定性条件为r/3的分支稳定的高精度显式差分格式；最后给出了数值例子，数值结果表明了本文格式较现有同类格式的优越性和理论分析的正确性。

In this paper, we construct the differential equation to solve the unconstrained optimization problem. Such methods solving the ill-conditioned problems are very effective. It indicates that the asymptotically stable region of explicit the Euler method to solve the differential equation equals to the descent region of the gradient method to solve the original unconstrained optimization problem.

我们发现，在用Euler方法求解二次优化问题的等价动力系统的方程时，由方法的步长确定的稳定区域对应于这些方法所得到的迭代公式的步长满足单调下降算法的条件确定的单调下降区域，因此我们可以利用这个性质构造解无约束优化问题的数值方法而不采用标准的常微分方程的数值求解公式。

We establish a differential equation system via Newton method, and prove that the solution of nonlinear complementarity problems is exact the equilibrium point of differential equation system.

应用了牛顿的方法建立了微分方程系统，证明了非线性互补问题的解是所构造微分方程系统的渐近稳定平衡点，并给出了算法，证明了算法具有二阶收敛速度。

The matrix differential equation is solved using method of steps and applying Laplace transform. Using this method and exact solution of the matrix differential equation with delayed arguments was....

待流场达稳态后，於注水井筛段注入追踪剂并在抽水井筛段量测浓度穿透曲线，使用适当数学模式分析其浓度穿透曲线及上、下井筛段泄降差，即可同时。。。。

In this thesis, we discuss several problems which exist to qualitative theory of the functional differential equation, within which we develop further two important theories, so-called the 3/2 - stability theory and the distribution of zeros of solutions of the functional differential equation.

本文中，我们对泛函微分方程定性研究中存在的若干理论问题进行探讨，对其中两个重要问题即3/2—稳定性理论和零点距估计问题，作了进一步推广。

In Chapters 3 and 4, we investigate the existence of periodic solutions of a class of second order functional differential equation and a class of third order functional differential equation, respectively, and obtain new sufficient conditions of their existence result of periodic solutions under growth conditions and linear growth condition, respectively.

第三章与第四章分别研究了一类二阶泛函微分方程及一类三阶泛函微分方程的周期解存在性，分别在增长条件及线性增长条件下，获得了这两类方程周期解存在性的新的充分条件，与文献中已知结果比较，我们所讨论的方程更为一般，所得结果较简洁且易于验证。

In Chapters 3 and 4, we investigate the existence of periodic solutions of a class of second order functional differential equation and a class of third order functional differential equation, respectively, and obtain new sufficient conditions of their existence result of periodic solutions under growth conditions and linear growth condition, respectively. Compared with some known results in the literature, the equations discussed by us are more general, and our results are concise and easy to be verified.

第三章与第四章分别研究了一类二阶泛函微分方程及一类三阶泛函微分方程的周期解存在性，分别在增长条件及线性增长条件下，获得了这两类方程周期解存在性的新的充分条件，与文献中已知结果比较，我们所讨论的方程更为一般，所得结果较简洁且易于验证。

In this paper we contribute the general integral formula of second order linear differential equation with constant coefficients by means of decreasing order So we can integrate directly to solve this kind differential equation .

本文通过降阶法给出了求二阶常系数线性微分方程通解的方法，并根据特征根的不同情形给出了具体的通解公式，即可通过积分直接求微分方程的通解。

Applying the Hermite polynomial expansion, this integral-differential equation is creatively transformed into deterministic differential equation.

创造性地使用Hermite多项式展开，将确定性的积分——微分方程转换为确定性的微分方程。

The integral inequality is a useful tool when we study the stability theory of differential equation, especially when we study the stability, the estimate of solution and the boundedness of differential equation.

在研究微分方程稳定性理论中，尤其在探讨微分方程的稳定性，解的估计及有界性的过程中，积分不等式是一强有力的工具。

There are different types of personal loans available.

有许多不同类型的个人贷款优惠。

The above mentioned teaching model of spiral rising can be used to avoid rigidness in teaching.

上述螺旋式上升的教学模式，可以避免教学形成模式後的僵化现象。