查询词典 difference differential equation

The thesis is organized as follows:In Chapter 1,a new partial differential equation model for Spontaneous Potential log in heterogeneous formations is introduced.At the same time,the existence and uniqueness of weak solution to the problem are proved,and the problem of resistance identification in SP log is studied.Furthermore,a jump condition capturing finite difference scheme is proposed and applied to solve such elliptic interface problems.The effects of various factors on SP response,which include objective layers resistivity,bed thickness,bore-hole diameter,invasion and water-flooded zones and so on,are investigated quantitatively by the proposed method, and satisfactory results are obtained.

具体安排如下：第一章首先建立复杂地层中自然电位测井的偏微分方程数学模型，证明了该边值问题弱解的存在唯一性，在此基础上研究了自然电位测井电阻率识别问题：然后发展了用于求解椭圆交界面问题的间断捕捉有限差分方法，利用该方法定量分析了目的层电阻率、地层厚度、井径、侵入带和水淹层等因素对自然电位测井响应的影响，取得了满意的结果。

By discussing the position hypothesis of fractional-dimension derivative about general function and the formula form the hypothesis of fractional-dimension derivative about power function, the concrete equation formulas of fractional-dimension derivative, differential and integral are described distinctly further, and the difference between the fractional-dimension derivative and the fractional-order derivative are given too. Subsequently, the concrete forms of measure calculation equations of self-similar fractal obtaining by based on the definition of form in fractional-dimension calculus about general fractal measure are discussed again, and the differences with Hausdorff measure method or the covering method at present are given. By applying the measure calculation equations, the measure of self-similar fractals which include middle-third Cantor set, Koch curve, Sierpinski gasket and orthogonal cross star are calculated and analyzed.

通过讨论一般函数的分维导数的位置假设及幂函数的分维导数的形式假设，进一步明晰了幂函数的分维导数、分维微分及分维积分的具体方程形式，给出分维导数与分数阶导数的区别，随后讨论了基于一般分形测度的分维微积分形式定义导出的自相似分形的测度计算方程具体形式，给出了其与目前 Hausdorff 测度方法的区别，并对包括三分 Cantor 集合、 Koch 曲线、 Sierpinski 垫片及正交十字星形等自相似分形在内的测度进行了计算分析。

Differential difference equation is a kind of powerful means to investigate the rule of natural phenomena, whose qualitative analysis has always been the hot spot subject to be studied in the recent years.

微分差分方程是用来描绘自然现象变化规律的一种有力工具，其定性分析一直是近年来研究的热点问题。

A sufficient condition for the oscillation of bounded solutions of a kind of second order neutral differential difference equation s established.

建立了一类二阶中立型微分差分方程有界解振动的充分条件，且当变系数都是常数时，该条件也是必要的；同时，根据该方程的"极限"方程建立了它自身的一个有界振动准则。

It simulates the human thought and the decision-making process, and solves the control difficult problem of complex system that describing is very difficult with the precise mathematical model (differential or difference equation).

基于知识驱动的拟人智能控制系统，是一种模拟人类思维和决策过程，解决难以用精确的数学模型来描述的复杂系统的控制难题的一种全新的控制系统。

The Fourier method and heuristic stability theory for the analysis of the computational stability criterion of the difference scheme of linear partial differential equation are also briefly introduced.

对分析线性偏微分方程差分格式计算稳定性判据的Fourier方法、启发性稳定性分析方法，也做了简要的介绍。

This main approach is also coincidence degree theory. Moreover, when the time scale T is chosen as the sets of real or integer numbers, the existence of periodic solutions for its differential or difference equation are obtained respectively.

若分别选取时标T为实数集或整数集时，则分别得到它的微分方程或差分方程周期解的存在性，这就避免了对这些生态系统的微分和差分方程周期解的存在性分别进行讨论。

Near the bifurcation point, the linear stability of difference differential equation which describes acoustooptic bistable systems is analyzed, the expression of resonance frequency and amplification multiple are given.

在分岔点附近，通过对描述布拉格型声光双稳系统的差分－微分方程进行线性稳定性分析，得到了系统对小信号放大时的共振频率，给出了放大倍数的表达式。

To discuss deeply, this article use indirect means to research by difference differential equation, that is: using the Liyapnof function to discuss the time delay stability of one-dimensionality force telepresence system in order to determine the time delay limits which could ensue the system work normal.

为了进一步深入讨论，本文还从差分微分方程入手，采用间接法进行进一步讨论，即：利用李亚普诺夫函数对一维力觉临场感系统的时延稳定性进行讨论，确定保障系统正常工作的时延界限。

Differential coefficient and difference simulation equation of gray model GM (1, 2), representing the relationship between 28d compressive strength and 4-32μ m particle content respectively is

颗粒粒级范围对强度的灰色系统关联度分析结果表明：对于普通硅酸盐水泥，4-8μm颗粒含量对水泥3d抗压强度的影响最大，8-16μm颗粒含量对水泥28d抗压强度的影响最大，对水泥90d抗压强度，则16-24μm颗粒的影响最大。28d抗压强度与4-32μm颗粒含量灰色模型GM（1，2）的微分方程和差分模拟式分别为

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。