查询词典 difference equation

In this paper, the finite difference method for the homogenous initial boundary value problem of symmetric regularized long-wave equation is considered.

本文考虑了具有齐次边界条件的对称正则长波方程的有限差分方法。

In this paper, we study the initial value problem of Duffing equation in the difference form with multiple-scale method, which is one of the perturbation method.

本文以摄动法中的多重尺度法为基础，讨论差分形式的Duffing方程的初值问题。

A finite difference method was derived for the analysis of time domain electric field integral equation of thin wire structures.

提出一种求解基于细线结构的时域电场积分方程的方法-有限差分方法。

A finite difference method is derived for the analysis of time domain electric field integral equation of thin wire-structures.

针对时域电场积分方程的矩量法求解过程的繁琐及算法的时序推进稳定性不好等问题，提出了一种有限差分法求解时域电场积分方程的方法。

At present the numerical simulation of electromagnetic method of finite difference method, finite element method, boundary element law, integral equation method, and so on were commonly used in the exploration.

目前电磁法勘探中常用的数值模拟方法主要有：有限差分法、有限单元法、边界单元法和积分方程法等。

In the forward aspect, the advantages and disadvantages of such methods as finite difference, finite element and integral equation as well as their development trend are discussed. In the inversion aspect, mainly linear and nonlinear inversions are analyzed, with a detailed discussion on the linear inversion methods both in the time domain and in the frequency domain as well as a prediction of their future development trend.

正演方面主要讨论了有限差分、有限元和积分方程法，分析了各种方法的优缺点、适用范围，并指出了未来发展趋势；反演方面主要讨论了线性反演和非线性反演，根据井间电磁波成像的性质，对时间域和频率域线性反演方法分别做了详细论述，并给出了未来发展趋势。

In the fifth part, we obtained a solution of the boundary function for the Laplace equation by knowing some of its interior points values of five-point difference approximation.

给出从Laplace方程的解的内点值求边界函数的方法。

By the analysis of dive and horizontal plane nonlinear model, the catastrophe model on de dive plane is deduced, and catastrophe stability is analysized. In the horizontal plane, simplified equation is gained by center manifold theory, then draws the conclusion that the stability of limit circle arises from critical point is relate to small difference of move point and critical point.

通过对潜艇垂直面和水平面非线性运动模型进行分析，导出垂直面运动的突变控制模型，并进行了突变稳定性分析；在水平面运动的非线性分析中，通过中心流形定理简化方程，得出临界点处极限环的稳定性与微差占的符号有关的结论，这样在无法或很难得到李亚普诺夫函数的情况下，可以通过这种方法判别临界点的稳定性。

In chapter two,we consider a lumped mass generalized difference scheme for linear integro-differential equation in two dimensions.Lp and error estimates of the generalized Ritz-Volterra projection u ? V and and -norm error estimates of Dk = 1,2 are made,then we obtain and -norm error estimates of u?

第二章考虑二维线性积分微分方程的广义差分集中质量法，建立了广义Ritz-Volterra投影，得到u-V_h~*u的W~(1，p)和L~p(2≤p≤∞)模误差估计和D_t~k，k=1，2的V~p和W~(1，p)(2≤p≤∞)模误差估计，从而得到u-u_h的最优W~(1，p)和L~p(2≤p≤∞)模误差估计。

In chapter three,we consider first order generalized difference scheme for linear Sobolev equation in two dimensions.Lp and W1,p-norm error estimates of the Ritz-Volterra projection u-Vhu and W1,p-norm super error estimate of uh-Vhu are made,so we obtain Lp and W1,p-norm error estimatesOf u-uh.

第三章考虑二维线性Sobolev方程的一阶广义差分格式，建立 Ritz－Volterra投影模误差估计和的模超收敛估计，从而得到的最优模误差估计。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。