查询词典 analytical differential

A generalized mathematical model was developed to describe the distribution of over-potential.Dimensionless variables μ and ω that characterize the polarization and influence of side electrode reaction in the system,were derived from modeling.Adomian's decomposition methodADM）was used to solve the nonlinear differential equation of the model to obtain an approximate analytical solution,which was in the form of algebraic expressions of infinite power series.By the solution,the relationship between over-potential distribution and average selectivity could be easily calculated without solving the nonlinear model time and again.

建立了描述超电势分布的普遍化数学模型，归纳出表征电极极化和副反应影响的量纲1数μ和ω，并用ADM（Adomian's decomposition method）对该非线性微分方程模型求解；所获得的逼近解代数表达式，可方便地计算不同参数下超电势分布对平均选择性的影响，而毋需反复求解模型微分方程。

The most common and most widely studied methods of all analytical approximation methods for nonlinear differential equations are the perturbation methods.

非线性振动由于其振动方程的特点，到现在还没有通用的解析求解方法，只能根据系统的特点采用一些特殊的方法来求解。

We have researched the decentralized stabilization problem of nonlinear large scale composite systems by differential geometric and analytical method, it is shown that the results are better than that one obtained by using only one of these two methods.

本文分别采用代数方法与分析方法、微分几何方法和分析方法相结合的方式讨论了比较广泛的非线性组合大系统的分散反馈镇定问题。

With the publication of the Dai Wei Ji Shi Ji, a translation of Loomis' textbook Elements of Analytical Geometry and of the Differential and Integral Calculus (1851), in 1859, the differential and integral calculus was introduced into China.

19世纪后期是中国数学由传统向近现代转化的一个重要时期，微积分是近代数学乃至大部分自然科学的最基础的理论，这个理论是从1859年出版的译著《代微积拾级》中介绍到中国来的。

Key words: partial differential equation; Lewy equation; real analytical; infinitely differential solution; compactly supported set

引用格 式：吴小庆。Lewy方程的无穷可微解。中国科技论文在线精品论文，2010，3(1)：19～27。

The second-order linear homogeneous differential equations in differential equation theory occupies an important position, but the second order differential equation has no general solution method, most of the solutions of these equations is difficult to obtain analytical expressions and even some impossible to obtain the solution of the form, and the second order differential equation solving is divided into homogeneous and inhomogeneous problems.

二阶线性齐次微分方程在微分方程理论中占有重要位置，但二阶变系数微分方程却没有一般的求解方法，大多数这类方程很难求得解的分析表达式甚至有的根本不可能求得其解的分析形式，并且二阶变系数微分方程的求解又分为齐次的和非齐次的问题。

First of all,we have given some of the basic concepts of differential equations, described the constant coefficient linear ordinary differential equation solution, for a class of second-order variable coefficient linear ordinary differential equation initial value problem, an approximate solution, the method is first unknown function of a definition for N sub-interval, and then in between each district within a constant coefficient ordinary differential equations similar to the replacement, the solution has been the problem as similar to the original analytical solution, and then gives a detailed second-order change order coefficient of linear homogeneous ordinary differential equation solution examples, the examples of the approximate method proposed in this paper is valid.

首先给出了微分方程的一些基本概念，讲述了常系数线性常微分方程的解法，针对一类二阶变系数线性常微分方程初值问题，提出了一个近似解法，本方法是先对未知函数的一个定义区间作N等分，然后在每一个小区间内用一个常系数常微分方程近似替换，所得到的解作为原问题的近似解析解，随后详细给出了一个求二阶变系数齐次线性常微分方程的解的实例，该实例说明本文提出的近似方法是有效的。

Three elements should be calculated in first-order circuit, which can synthesise analytical solution. Second-order series RLC and parallel RLC both can be calculated by the general function, which uses the Matlab to calculate differential equations. Generally, second-order and high-order circuits use Laplace transformation to formulate circuit equation, and get analytical solution by using Laplace inverse transform.

一阶电路先计算3要素，后合成解析结果；RLC串联和并联的二阶电路采用自编的通用函数计算，自编函数采用了Matlab求解微分方程的符号运算方法；一般的二阶电路和高阶电路采用拉氏变换列写电路方程，再用拉氏反变换得到解析结果。

Therefore,it is necessary to research diffusion equation for suspended sediment because it describes the sediment move process in the water body.The equation is a various coefficients second-order linear partial differential equa-tion,such equation under complex boundary condition is very difficult to get its analytical solution,while its numerical solution relative analytical solution is more easier and has the obvious superiority:simple,the computation convenience.but to get a kind of difference format which is good accuracy and stability is not easy.

泥沙扩散方程实际上是一个变系数的二阶线性偏微分方程，这样的方程在各种复杂边界条件下求解是十分困难的，求它的解析解在数学上存在着难以克服的障碍，无法求出其精确解，因此常用数值方法求它的近似解，相比较而言，数值方法有着明显的优势：即简单灵活、计算方便快捷，但要寻找一种精度高、稳定性好、计算方便的差分格式也并非易事。

On applying the theory of differential geometry, the research shows the procedure for determining the required cutter path for cutting conical cam profile using a NC milling machine based on the analytical profile expression of conical cam with oscillation conical roller follower or with a translating conical roller follower established in 3D space. The analytical expression of cutter path is provided for a tapered endmill cutter, whose size may be identical to or smaller than that of the conical roller.

应用微分几何理论，以在3维空间所建立的圆锥滚子摆动从动件和直动从动件圆锥凸轮机构凸轮廓面的解析表达式为基础，对数控铣床加工圆锥凸轮廓面所需刀具轨迹方程的建立方法进行了研究，根据所采用的锥形刀尺寸等于或小于圆锥滚子尺寸的情况，推导出相应的刀具轨迹方程的解析表达式。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。