特征方程

The physical interpretations,character and suppressing methods of absolute instability were analyzed and verified by a W-band TE_(01) experiment.

通过回旋行波管色散方程，详细分析了W波段基波回旋行波管绝对不稳定性的形成和特征，提出了采用多段损耗波导来抑制绝对不稳定性的方法。

This dissertation is changed into two parts. The first part, the theory and application about Wu-Ritt differential characteristic sequence method are discussed, which involves the theories of differential equations, abstract algebra and computer algebra etc.

本文共分两部分，第一部分讨论微分特征列法的理论和应用问题，涉及到微分方程，抽象代数，计算机代数等重要学科。

The formal solution of partial differential equations is given on characteristic line, the existence of the optimal control is proven by using Ekeland\'s variational principle, Gronwall Lemma and adjoint system, then the necessary condition of optimality is obtained by means of the conception of normal cone.

用特征线法表示出偏微分方程的形式解，利用Ekeland变分原理，Gronwall引理和共轭系统证明了最优控制的存在性，并借助于法锥概念得到了最优控制的必要性条件。

Base on the systematically geological investigation and study, we choose to use aremote sensing data source,the geography control data source(1:50,000relief map of Qiaojia and measured GPS ) as the data source of this research, adopt"Digital Landslide"processing image data, and carry on time-space analysiscombining geological investigation and related data. Application aerodynamicist theories, some important conclusions that obtained from the wind-tunnel experiment,and according to the time –space analysis result, we analyzed the landslide dammingmovement mechanism, presumed the movement format of this high-speed landslide,studied the formation mechanism and the movement characteristic of this landslide ,calculated it's movement equation, applied VC language to write calculationprocedure of each stage of the landslide, computed movement speed and displacement,and made sure its possible stop district.

本文在前人研究的基础上，选用遥感数据源、地理控制数据源(1：5万巧家幅地形图及实测GPS点)为本研究的数据源，采用"数字滑坡"技术处理图像数据，结合野外实地考察及相关资料对石膏地滑坡进行了时空分析；运用空气动力学理论，采用胡厚田等人在风洞实验中得出的许多重要结论，根据时空分析结果分析滑坡的运动机理，推测高速滑坡的运动模式；研究石膏地滑坡的形成机理、运动特征及运动方程，并用C++语言在VC开发环境中编写滑坡各阶段的计算程序，计算滑坡的流动速度及运动位移，确定其可能的停止区域。

Introducing the affixation variables instead of solving non linear equation, we can make use of several corresponding points on the object and obtain a group of linear equations.

通过引入了中间变量，以避免求解非线性方程，在物体上选择多个特征点，可以得到一个线性方程组。

Function of air valve for water hammer protection is analyzed with method of characteristics through practical engineering example.

针对长距离有压输水系统的特点，从基本的空气动力学方程入手，分析推导了空气阀的数学模型，并采用水锤计算的特征线方法，进行了空气阀水锤防护的实例分析。

And the texture characters of flow canals.

推导出了描述热液管流上侵动力学特征的柏努利方程关系式，表明热液的流速与所处构造压力差、流体的性质，以及流动通道的结构特征有关。

Based this better correlation and using the multiple regression method, we reconstructed the historical spring and summer flood/drought index from 1835 to 1996. The reconstructed series shows obvious decadal variability, and thus provides a reliable reference for the local climatic change study.

根据此显著相关性，利用多元回归方程重建了历史时期的春夏季旱涝指数，分析表明天目山地区春夏季旱涝的发生具有比较明显的年代际变化特征，为研究该地区气候变化特征提供了较可靠的参考依据。

The theories proposed by Wilson (1994) were adopted to describe the fundamental behaviors of temperature and variation of suction of soil. The Darcy's law and Pick's law described the flows and evaporation of water respectively. Some proposed assumptions including the characteristic curve of volumetric water content and hydraulic conductivity were only related to the suction of unsaturated soil. The coefficient of latent heat for water was a linear function of temperature; and the heat conductivity was calculated according to the equation proposed by De Vries.

对于土体的温度和吸力变化特征，采用Wilson提出的理论加以描述，在此理论中，分别利用Darcy和Fick定律描述水和蒸汽的流动规律，土水特征曲线和水力传导系数假定仅仅相关于非饱和土吸力，水的潜热系数是温度的线性函数，温度传导系数采用De Vries建议方程加以计算。

Based on the Roe′s approximate Riemann solver, this paper presents the flux balance Godunov scheme for the shallow water equation with source terms.

以Roe的近似Riemann解为基础，将源项按特征方向进行特征分解，建立了带源项浅水方程的通量平衡Go dunov求解格式。

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