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141.
142.
QIAOYong-Fen LIRen-Jie MAYong-Sheng 《理论物理通讯》2004,42(6):801-804
Using the Lie Symmetry under infinitesimal transformations in which the time is not variable, the nonNoether conserved quantity of nonholonomic system having variable mass and unilateral constraints is studied. The differential equations of motion of the system are given. The determining equations of Lie symmetrical transformations of the system under infinitesimal transformations are constructed. The Hojman‘s conservation theorem of the system is established. Finally, we give an example to illustrate the application of the result. 相似文献
143.
FANG Jian-Hui 《理论物理通讯》2004,41(3):349-352
The definition and criterion of the Mei symmetry of
a relativistic variable mass system are given. The relation between
the Mei symmetry and the Noether symmetry of the system is found
under infinitesimal transformations of groups. The conserved
quantities to which the Mei symmetry and Noether symmetry of
the system lead are obtained. An example is given to illustrate
the application of the result. 相似文献
144.
A new conserved quantity of mechanical systems with differential constraints 总被引:1,自引:0,他引:1
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A new conserved quantity of non-Noether symmetry for the mechanical systems with differential constraints is studied. First, the differential equations of motion of the systems are established. Then, the determining equations and restriction equations of the non-Noether symmetry are obtained and a new conserved quantity is given. Finally, an example is given to illustrate the application of the results. 相似文献
145.
Filtering for linear systems with noise correlation and its application to singular systems
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In this paper, an optimal filter for a stochastic linear system with previous stage noise correlation is designed.Based on this result, together with the decomposition techniques of the stochastic singular linear system, the design ofan optimal filter for a stochastic singular linear system is given. 相似文献
146.
For a nonholonomic system, a new type of Lie symmetrical non-Noether conserved quantity is given under general infinitesimal transformations of groups in which time is variable. On the basis of the invariance theory of differential equations of motion under infinitesimal transformations for t and q_s, we construct the Lie symmetrical determining equations, the constrained restriction equations and the additional restriction equations of the system. And a new type of Lie symmetrical non-Noether conserved quantity is directly obtained from the Lie symmetry of the system, which only depends on the variables t, q_s and \dot{q}_s. A series of deductions are inferred for a holonomic nonconservative system, Lagrangian system and other dynamical systems in the case of vanishing of time variation. An example is given to illustrate the application of the results. 相似文献
147.
148.
The differential equations of motion of a relativistic variable mass system are given.By using the invariance of the differential equations under the infinitesimal transformations of groups,the determining equations and the restriction equations of the Lie symmetries of a relativistic variable mass system are built,and the structure equation and the conserved quantity of the Lie symmetries are obtained.Then the inverse problem of the Lie symmetries is studied.The corresponding Lie symmetries are found according to a known conserved quantity.An example is given to illustrate the application of the result. 相似文献
149.
对D型截面托卡马克用平板模型求出等离子体中的场量及微分场量的分布,由此对入射波进行波束划分,并给出每一波束的初始条件.用射线轨迹方法计算并叠加每一波束功率沉积,得到快波功率沉积的计算结果. 相似文献
150.