微分的

The main idea of the finite difference method is as follows: We consider the discrete difference equation with the finite alphas as approximate substitution for the differential equation with the continuous variant and boundary conditions.

有限差分方法的基本思想是用离散的，只含有有限个未知数的差分方程去近似代替连续变量的微分方程及边界条件，并把相应的差分方程解作为微分方程的近似解。

In this paper,the asymptotic property for two kinds of ecological systems and oscillation for solutions of a neutral differential equations is studied by employing differential inequalities and using eigenvalue analysis,iterative algorithm,induction and comparison theorem etc.Here, the system\'s asymptotic property includes the uniform persistence,the global attractability of the solutions,the asmptotic stability of the solutions and the oscillation of solutions.

本文利用微分不等式、特征根分析法、迭代法、归纳法及比较原理等方法和理论，研究了两类生态模型解的渐近性和一类脉冲中立型微分方程解的振动性，其中包括模型的一致持久生存性，正平衡态的全局吸引性、局部与全局渐近稳定性以及解的振动性。

In this paper we study the method of interpolation by radial basis functions in H~k(k ≥ 1) and give some error estimates. By means of such interpolation with a special kind of radial basis function, we construct a basis in H~k(k ≥ 1). Combined with the Galerkin method, this theory can be applied to solve boundary value problems for elliptic partial differential equations (such as the third boundary value problem for Poisson equation and the corresponding problem for the biharmonic equation), and some numerical experiments are also given.

本文从求解偏微分方程的角度出发，在被逼近函数u属于一般的Sobolev空间H~k(k≥1)的情形，引入了一种径向基函数插值方法，并建立了相应的误差估计；再利用这种插值性质，从一类特殊径向基函数出发构造Sobolev空间的一组基，针对Poisson方程第三类边值问题和重调和方程类似边值问题，为用无网格算法求解偏微分方程边值问题建立了相应的理论，并通过算例来验证了这一算法。

By transforming the interlace series type linear differential equation with coefficient containing binomial coefficients and arrangement number into the linear differential equation of successive integral,the theory and method for solving this kind of equation are determined.

通过把系数含有二项式系数与排列数的交错级数型线性微分方程化为可逐次积分的线性微分方程，找出了求这类方程通解的方法与理论，把所得定理给出了严格的证明，并通过实例介绍了它的应用。

This text utilizes the stability theory of differential equation, establishes the mathematical model of praying on the relation among the living beings, then according to the characteristic of differential equation group set up, through analyze to its equalization point,discuss the rail line distribution situation and overall stability, studies the dynamic change situation of every species during sufficient long time slot.

摘要本文利用微分方程稳定性理论，建立生物间捕食关系的数学模型，然后根据建立的微分方程组的特性，通过对其平衡点分析，轨线分布情况以及全局稳定性的讨论，研究出各物种在充分长时间段中的动态变化情况。

In 1943 - 1945, he worked in the Institute for Advanced Study at Princeton. Having arrived in the United States for two months, he finished his famous paper entitled "A simple intrinsic proof of the Gauss-Bonnet formula for closed Riemannian manifolds", which inspired other differential geometers.

抵美两个月后，即完成其著名的论文──《闭曲面流形高斯--博内公式(Gauss-Bonnet Formula)的一个简单的内蕴证明》，对於后来微分几何的发展和微分几何学者的研究影响深远。

An analytical model describing the dispersion with an exponential dispersion function is built, which be transformed into CDE problem with variable coefficient, using hypergeometric function and inversion technique, an analytical solution for two type boundary conditions is obtained.

文章对于具有指数弥散函数的弥散过程建立了对流-弥散微分方程模型，应用积分变换将问题转化为具有变系数的常微分方程问题；对于两种类型的边界条件，应用超几何函数和反演技术得到了问题的解析解，并分析了指数弥散过程和常数弥散过程的不同性质。

Rties of the system are researched by using the comparison theorem of impulsive ordinary differential equations and using the solutions of dominating inpulsive ordinary differential equation to control and estimate the solutions of the system.

利用脉冲常微分方程的比较定理以及利用相应的脉冲常微分方程的解控制和估计所讨论模型的解，研究了系统模型的解的渐近性质。

Continuity equation and motion equation which can be applied to cone-shaped pipes are obtained and finite difference method for them is brought forward.

根据非稳定流的一维流动理论，对圆锥形管道中的瞬变流动进行了分析，推导出了适用于圆锥形管道的连续性微分方程和运动微分方程，给出了这两个方程的有限差分解法，同时对计算结果进行了相对误差的对比分析。

An optical system with refraction and total internal reflection was proposed according to the luminous characteristic of LED and the law of energy conservation. The ordinary differential equations satisfying the spots on the contour curve of TIR refractive and reflective planes were established. The coordinates of points on profile curves were obtained by solving these ordinary differential equations using Runge-Kutta method. The profile curves were acquired by curve fitting of the coordinate spots with software UG, and then TIR model of the projector and data of the surface shape suitable for NC manufacture were obtained.

根据LED的发光特性以及能量守恒定律选择采用折射全反射光学系统，通过建立TIR折射面及全反射面轮廓曲线上的点所满足的常微分方程，利用RungeKutta求解常微分方程得到轮廓曲线上点的坐标，再在UG中对坐标点进行曲线拟合得到轮廓曲线，进而得到TIR模型及适合数控加工的面形数据。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷