特征方程

Based on the theory of tidal flow and sediment motion, a 2-D depth-integrated mathematical model for the Jiaojiang Estuary is developed by using explicit scheme of finite difference on the triangle elements. The results show that the rotary currents occurring in this area can be simply and effectively simulated by the model. Meanwhile, the suspended sediment concentration simulated is in agreement with the field data.

本文根据椒江口实测水文地形资料，从平面二维水流泥沙基本方程和基本理论出发，采用三角单元有限差分法对水流泥沙方程显示求解，对椒江口潮流泥沙进行了数值模拟，模型简单实用，较好地再现了具有旋转潮波性质的椒江河口水流运动特征，含沙量场也得到了基本正确的反映。

Some sufficient conditions for the forced oscillation of solutions of the equations are obtained using the Robin eigenfunction and the impulsive delay differential inequalities.

考虑一类具强迫项的满足Robin边值条件的脉冲时滞抛物型方程，利用Robin特征函数和脉冲时滞微分不等式获得了这类方程解强迫振动的若干充分条件。

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。

In this dissertation,we consider the following nonlinear singular partial differentialequation in complex domain 〓where u=uis a unknow function,Fis a holomorphic function withrespect to the variables〓.

本文主要考虑的问题是复空间中的非线性全特征型奇性偏微分方程解的性质，即考虑如下偏微分方程〓的解的性质，其中〓为未知函数，F是一个关于变量〓〓的已知全纯函数。

Sobolev equation is widely used in many areas, such as hydromechanics, thermodynamics and so on.

中文摘要： Sobolev方程是在流体力学，热力学等领域应用广泛的一类方程，其有限元数值方法研究已有很多工作，如[5]中提出了位移有限元法，[9]中建立了特征混合元方法，[7]提出了H1-Galerkin混合有限元方法，[10]中提出了最小二乘混合元方法。

A new graph theory methodology is presented for analysis of the unsteady flows in open channel network, including the structure and characteristics of the incidence matrix A, continuity equation and energy equation with matrix A.

提出了新的渠网非恒定流图论原理，包括适应渠网非恒定流特征的节支关联矩阵A的构建方法及性质分析，基于A的节点连续性矩阵方程和节点水深矩阵方程等。

After discussing the structural conditions of the existence of the active network solutions, the state equations in normal form over F of electrical network which are suited for studying the character of network structure are derived. If there is no loop containing only capacitor and independent voltage sources, and if there is no cut-set containing only inductors and independent current-sources, both matrix A and B in ?

在探讨了有源网络解存在的结构条件下，推导了适合研究网络结构特征的多元有理函数域上电网络的范式状态方程：如果不存在仅由独立电压源和电容器构成的回路，且不存在仅由独立电流源和电感器组成的割集，则无论是有源网络还是无源网络，在网络的范式状态方程？

Feature parameters are achieved by comparing the coefficient of standard representation and general representation. As for cone, parameter of general representation has no explicit geometric meaning and can not reflect design intent.

基于二次曲面的统一表示方程，采用最小二乘法进行参数拟合，通过对比其标准形式和二次曲面的统一表示方程，确定圆柱曲面特征带有明显几何意义的参数圆柱轴线法矢量、圆柱的中心和半径。

At the chapters of theory analysis,constitutive equation of dusty is deduced from the results of the experiment and related theories about oblique shock wave.after that relationship of parameters reflecting flow-field characteristic are deduced from theories of shock wave polar .The paper set up conservation equations depicting gas and solid flow-field by double fluid model,thus equations and constitutive equation of granular phase form closed equations.then the paper uses AUSNT vector splitting method to numerically calculate the equations.

理论部分主要包括：利用实验测试结果以及斜激波理论测试出该堆积粉尘的本构方程，然后利用和激波极曲线理论得到反映流场特征参数的变化曲线；本文还利用双流体模型，建立了描述气—固两相流动的守恒型方程组，与本构方程一起构成封闭方程组。

He also extended quasi-geostrophic non-acceleration theorem to primitive equation non-acceleration theorem.

他在国际上首创湿倾斜涡度发展理论和全型垂直涡度方程，成功地揭示青藏高原西南涡和夏季江淮流域的暴雨发展机理，揭示副热带高压形态变异的成因；证明创新的原始方程中的无加速定理以及大气运动的动力强迫和热力强迫的调配率；开展创新性气候动力研究，揭示中高纬和热带海气相互作用差异的机理及厄尔尼诺影响台风频率的机制，继承和发展了我国学者关于青藏高原对大气环流和天气气候影响的研究；在国际上首次把亚洲季风爆发分为三个阶段，证明由于中高纬度的强地转性和斜压性使其海气相互作用的特征与热带显著不同；首次用数值模式提出厄尔尼诺影响台风的机制，得到国际上的高度评价。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失