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111.
1.引言 近年来,一类新的非重叠区域分解方法一非匹配网格区域分解法,日益引起人们的广泛兴趣,并已成为当今区域分解方法研究的热门课题。这类区域分解方法的特点是:相邻子区域在公共边(或面)上的结点可以不重合,从而能解决许多传统区域分解方法不便解决的问题(如变动网格问题).目前主要有两类方法来处理这种区域分解的强非协调性:Mortar无法(见[1-2]和[9-10])和拉格朗日乘子法(见[5],[8],[11]和[12]).拉格朗日乘子法比Mortar无法有明显的优点:(1)界面变量(即拉格朗日乘子)… 相似文献
112.
Integrating Factors and Conservation Theorems of Lagrangian Equations for Nonconservative Mechanical System in Generalized Classical Mechanics 总被引:1,自引:0,他引:1
QIAO Yong-Fen ZHAO Shu-Hong 《理论物理通讯》2006,46(1):43-45
The conservation theorems of the generalized Lagrangian equations for nonconservative mechanical system are studied by using method of integrating factors. Firstly, the differential equations of motion of system are given, and the definition of integrating factors is given. Next, the necessary conditions for the existence of the conserved quantity are studied in detail. Finally, the conservation theorem and its inverse for the system are established, and an example is given to illustrate the application of the result. 相似文献
113.
YANGGuo-Hong WANGYu-Sheng DUANYi-Shi 《理论物理通讯》2004,42(2):185-188
In the light of C-mapping method and topological current theory, the contribution of disclination lines to free energy density of liquid crystals is studied in the single-elastic constant approximation. It is pointed out that the total free energy density can be divided into two parts. One is the usual distorted energy density of director field around the disclination lines. The other is the free energy density of disclination lines themselves, which is shown to be centralized at the disclination lines and to be topologically quantized in the unit of kn/2. The topological quantum numbers are determined by the Hopf indices and Brouwer degrees of the director l~eld at the disclination lines, i.e. the disclination strengths. From the Lagrange‘s method of multipliers, the equilibrium equation and the molecular field ofliquid crystals are also obtained. The physical meaning of the Lagrangian multiplier is just the distorted energy density. 相似文献
114.
LUOShao-Kai HUANGFei-Jiang LUYi-Bing 《理论物理通讯》2004,42(6):817-820
The order reduction method of the relativistic Birkhollian equations is studied. For a relativistic autonomous Birkhotffian system, if the conservative law of the Birkhotffian holds, the conservative quantity can be called the generalized energy integral. Through the generalized energy integral, the order of the system can be reduced. If the relativisticBirkhoffian system has a generalized energy integral, then the Birkhoffian equations can be reduced by at least twodegrees and the Birkhoffian form can be kept. The relations among the relativistic Birkhoffian mechanics, the relativistic Hamiltonian mechanics and the relativistic Lagrangian mechanics are discussed, and the Whittaker order reduction method of the relativistic Lagrangian system is obtained. And an example is given to illustrate the application of theresult. 相似文献
115.
Quantum gauge theory of gravity is formulated based on gauge principle. Because the Lagrangian has strict local gravitational gauge symmetry, gravitational gauge theory is a perturbatively renormalizable quantum theory. Gravitational gauge interactions of scalar field are studied in this paper. In quantum gauge theory of gravity, scalar field minimal couples to gravitational field through gravitational gauge covariant derivative. Comparing the Lagrangian for scalar field in quantum gauge theory of gravity with the corresponding Lagrangian in quantum fields in curved space-time, the definition for metric in curved space-time in geometry picture of gravity can be obtained, which is expressed by gravitational gauge field. In classical level, the Lagrangian and Hamiltonian approaches are also discussed. 相似文献
116.
本文以依存语法作为语言模型,首先提出了一种全新的句子分析策略,分析在两极上进行,一级是基于中心动词同其他成分间的约束关系,通过寻找汉语语义类之间可能存在的句法关系,实现句子成分过滤,完成句子主干提取,另一级是上下文级,将语法,语义和语境信息一体化,结合依存语法确定汉语句子中各成分间的依存这后给出了一种快有效的用于完成句子分析的松驰匹配迭代算法,通过实验表明了该分析策略和算法的可行性。 相似文献
117.
A field method for integrating the equations of motion of mechanico--electrical coupling dynamical systems 下载免费PDF全文
A field method for integrating the equations of motion for mechanico-electrical coupling dynamical systems is studied. Two examples in mechanico-electrical engineering are given to illustrate this method. 相似文献
118.
119.
关于条件极值的一个充分性条件 总被引:4,自引:1,他引:3
对于求多元函数的条件极值问题,有下面熟知的拉格朗日乘数法为了求函数f(x,y,z)在附加条件φ(x,y,z)=0下的极值,令F(x,y,z)=f(x,y,z)+λφ(x,y,z)则方程组Fx(x,y,z)≡fx(x,y,z)+λφx(x,y,z)=0... 相似文献
120.
任何一个二次型f=n↑∑↑i,j=1αijxixj都可以通过非退化的线性变换变成标准形f=λ1y1^2 λ2y2^2 … λnyn^2,这个问题不仅在数学上,而且在物理学、工程学、经济学等领域中都是一个重要的问题,变换的方法很多,但工程数学教材中一般只用了正交变换法和拉格朗日配方法,现以一题为例, 相似文献