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91.
ZHANG Hong-Hao YAN Wen-Bin J.K. Parry LI Xue-Song 《理论物理通讯》2008,49(3):723-724
The compact form of the electroweak chiral Lagrangian is a reformulation of its original form and is expressed in terms of chiral rotated electroweak gauge fields, which is crucial for relating the information of underlying theories to the coefficients of the low-energy effective Lagrangian. However the compact form obtained in previous works is not complete. In this letter we add several new chiral invariant terms to it and discuss the contributions of these terms to the original electroweak chiral Lagrangian. 相似文献
92.
The series composed by beam mode function is used to approximate the displacement function of constrained damping of laminated cantilever plates, and the transverse deformation of the plate on which a concentrated force is acted is calculated using the principle of virtual work.By solving Lagrange's equation, the frequencies and model loss factors of free vibration of the plate are obtained, then the transient response of constrained damping of laminated cantilever plate is obtained, when the concentrated force is withdrawn suddenly.The theoretical calculations are compared with the experimental data, the results show:both the frequencies and the response time of theoretical calculation and its variational law with the parameters of the damping layer are identical with experimental results.Also, the response time of steel cantilever plate, unconstrained damping cantilever plate and constrained damping cantilever plate are brought into comparison, which shows that the constrained damping structure can effectively suppress the vibration. 相似文献
93.
Heavy gauge bosons such as W' are expected to exist in many extensions of the Standard Model. In this paper, the most general Lagrangian for the interaction of W' with top and bottom quarks is considered. This Lagrangian consists of V- A and V + A structure with in general complex couplings. Such interactions produce an Electric Dipole Moment (EDM) for the top quark at one loop level. We predict the allowed ranges for the mass and couplings of W' by using the upper limit on the top quark EDM. 相似文献
94.
We present the classical solution of Lagrange equations for the black hole with a global monopole or with a cosmic string. Then we obtain the wavefunction of the space-time by solving the Wheeler-De Witt equation. De Broglie-Bohm interpretation applied to the wavefunction gives the quantum solution of the space-time. In the end, the quantum effect on Hawking radiation is studied. 相似文献
95.
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
96.
97.
解不适定算子方程的一个定常二步隐式迭代法 总被引:1,自引:0,他引:1
1.引言 设X,Y是两个Hilbert空间,A:X→Y是有界线性算子,考虑算子方程 Ax=y(1.1)如果A的值域R(A)在Y中非闭,则方程(1.1)是不适定的[1].许多应用科学中都归结出这一类方程,特别地,许多反问题是不适定的[2,3].本文考虑方程(1.1)的 Moore-Penrose广义解,这里A是算子A的Moore-Penrose广义逆[1].A+y存在当且仅当本文均作这一假设.在实际中,通常代替(1.1)的是扰动方程这里右端项,为一给定的误差水平,Q是Y到R(A)的正交投影算子.对扰… 相似文献
98.
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
99.
The Lagrangian and the Lie symmetries of charged particle motion in homogeneous electromagnetic field 下载免费PDF全文
In this paper, a constant of motion of charged particle motion in
homogeneous electromagnetic field is derived from Newton's equations and the
characteristics of partial differential equation, the related
Lagrangian is also given by means of the obtained constant of motion. By
discussing the Lie symmetry for this classical system, this paper
obtains the general
expression of the conserved quantity. It is shown that the conserved
quantity is the same as the constant of motion in essence. 相似文献
100.
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