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1.
In this paper, we study the Noether-form invariance of nonholonomic mechanical controllable systems in phase space. Equations of motion of the controllable mechanical systems in phase space are presented. The definition and the criterion for this system are presented. A new conserved quantity and the Noether conserved quantity deduced from the Noether-form invariance are obtained. An example is given to illustrate the application of the results.  相似文献   

2.
非Chetaev型非完整可控力学系统的Noether-形式不变性   总被引:2,自引:0,他引:2       下载免费PDF全文
夏丽莉  李元成  王静  后其宝 《物理学报》2006,55(10):4995-4998
基于函数对时间的全导数采用沿系统的运动轨线方式, 研究非Chetaev型非完整可控力学系统的Noether-形式不变性. 给出非Chetaev型非完整可控力学系统的Noether-形式不变性的定义和判据. 由Noether-形式不变性同时得到了Noether守恒量和新型守恒量. 并举例说明结果的应用. 关键词: 非Chetaev型非完整系统 可控力学系统 Noether-形式不变性 守恒量  相似文献   

3.
夏丽莉  Li Yuan-Cheng 《物理学报》2008,57(8):4652-4656
在时间不变的特殊无限小变换下,研究相对论性变质量非完整可控力学系统的非Noether守恒量——Hojamn守恒量.建立了系统的运动微分方程, 给出了系统在特殊无限小变换下的形式不变性(Mei对称性)的定义和判据以及系统的形式不变性是Lie对称性的充分必要条件.得到了系统形式不变性导致非Noether守恒量的条件和具体形式.举例说明结果的应用. 关键词: 相对论 非完整可控力学系统 变质量 非Noether守恒量  相似文献   

4.
非完整系统的形式不变性与Hojman守恒量   总被引:5,自引:0,他引:5       下载免费PDF全文
罗绍凯  郭永新  梅凤翔 《物理学报》2004,53(8):2413-2418
研究非完整力学系统的形式不变性导致的非Noether守恒量——Hojman守恒量. 在时间不变的特殊无限小变换下,给出非完整系统形式不变性的确定方程、约束限制方程和附加限制方程,提出并定义弱(强)形式不变性的概念. 研究特殊形式不变性导致特殊Lie对称性的条件,由系统的特殊形式不变性,得到相应完整系统的Hojman守恒量以及非完整系统的弱Hojman守恒量和强Hojman守恒量. 给出两个经典例子说明结果的应用. 关键词: 分析力学 非完整系统 形式不变性 非Noether守恒量 Hojman守恒量  相似文献   

5.
夏丽莉  李元成 《物理学报》2007,56(11):6183-6187
研究相空间中非完整可控力学系统的对称性摄动与绝热不变量. 列出相空间中未受扰非完整可控力学系统的形式不变性导致的Noether守恒量. 基于力学系统高阶绝热不变量的定义,研究小扰动作用下相空间中非完整可控力学系统的形式不变性摄动与绝热不变量,给出了精确不变量与绝热不变量存在的条件与形式,并举例说明结果的应用.  相似文献   

6.
王廷志  孙现亭  韩月林 《物理学报》2014,63(10):104502-104502
研究了相空间中相对运动完整力学系统的共形不变性与守恒量.给出了该系统共形不变性的定义,并推导出相空间中相对运动完整力学系统的运动微分方程具有共形不变性并且是Lie对称性的充分必要条件.利用规范函数满足的结构方程导出该系统相应的守恒量,并给出应用算例.  相似文献   

7.
闫向宏  方建会 《中国物理》2006,15(10):2197-2201
This paper focuses on studying non-Noether conserved quantities of Lie symmetry and of form invariance for a mechanical system in phase space under the general infinitesimal transformation of groups. We obtain a new non-Noether conserved quantity of Lie symmetry of the system, and Hojman and Mei's results are of special cases of our conclusion. We find a condition under which the form invariance of the system will lead to a Lie symmetry, and, further, obtain a new non-Noether conserved quantity of form invariance of the system. An example is given finally to illustrate these results.  相似文献   

8.
Conformal invariance and a new type of conserved quantities of mechanical systems with variable mass in phase space are studied. Firstly, the definition and determining equation of conformal invariance are presented. The relationship between the conformal invariance and the Lie symmetry is given, and the necessary and sufficient condition that the conformal invariance would be the Lie symmetry under the infinitesimal transformations is provided.Secondly, a new type of conserved quantities of the conformal invariance are obtained by using the Lie symmetry of the system. Lastly, an example is given to illustrate the application of the results.  相似文献   

9.
张明江  方建会  路凯  张克军  李燕 《中国物理 B》2009,18(11):4650-4656
This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non-conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conformal invariance of the system are presented. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The necessary and sufficient condition that conformal invariance of the system would have Lie symmetry under single-parameter infinitesimal transformations is obtained. The corresponding conserved quantity of conformal invariance is derived with the aid of a structure equation. Lastly, an example is given to illustrate the application of the results.  相似文献   

10.
In this paper, the Lie-form invariance of a type of non-holonomic singular systems is studied. The differential equations of motion of the systems are given. The definition and the criterions of the Lie-form invariance for the systems are presented. The Hojman conserved quantity and the Mei conserved quantity are obtained. An example is given to illustrate the application of the results.  相似文献   

11.
张毅 《中国物理 B》2009,18(11):4636-4642
This paper is devoted to studying the conformal invariance and Noether symmetry and Lie symmetry of a holonomic mechanical system in event space. The definition of the conformal invariance and the corresponding conformal factors of the holonomic system in event space are given. By investigating the relation between the conformal invariance and the Noether symmetry and the Lie symmetry, expressions of conformal factors of the system under these circumstances are obtained, and the Noether conserved quantity and the Hojman conserved quantity directly derived from the conformal invariance are given. Two examples are given to illustrate the application of the results.  相似文献   

12.
A non-Noether conserved quantity, i.e., Hojman conserved quantity, constructed by using Mei symmetry for the nonholonomic controllable mechanical system, is presented. Under general infinitesimal transformations, the determining equations of the special Mei symmetry, the constrained restriction equations, the additional restriction equations, and the definitions of the weak Mei symmetry and the strong Mei symmetry of the nonholonomic controllable mechanical system are given. The condition under which Mei symmetry is a Lie symmetry is obtained. The form of the Hojman conserved quantity of the corresponding holonomic mechanical system, the weak Hojman conserved quantity and the strong Hojman conserved quantity of the nonholonomic controllable mechanical system are obtained. An example is given to illustrate the application of the results.  相似文献   

13.
王静  李元成  夏丽莉  后其宝 《中国物理》2006,15(8):1665-1668
In this paper the Lie-form invariance of the non-holonomic systems with unilateral constraints is studied. The definition and the criterion of the Lie-form invariance of the system are given. The generalized Hojman conserved quantity and a new type of conserved quantity deduced from the Lie-form invariance are obtained. Finally, an example is presented to illustrate the application of the results.  相似文献   

14.
研究相对论性转动变质量非完整可控力学系统的非Noether守恒量——Hojman守恒量. 建立了系统的运动微分方程, 给出了系统在特殊无限小变换下的Mei对称性(形式不变性) 和Lie对称性的定义和判据, 以及系统的Mei对称性是Lie对称性的充分必要条件. 得到了系统Mei对称性导致非Noether守恒量的条件和具体形式. 举例说明结果的应用. 关键词: 相对论性转动 可控力学系统 变质量 非Noether守恒量  相似文献   

15.
质量变化对力学系统形式不变性和守恒量的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
葛伟宽 《物理学报》2005,54(6):2478-2481
研究质量变化对力学系统形式不变性和守恒量的影响.给出常质量系统和变质量系形式不变性的判据方程.比较两个判据方程得到质量变化时形式不变性仍保持的条件.给出两个系统有同样守恒量的条件.举例说明结果的应用. 关键词: 分析力学 变质量系统 形式不变性 守恒量  相似文献   

16.
完整力学系统的Lie-形式不变性   总被引:2,自引:0,他引:2       下载免费PDF全文
葛伟宽  张毅 《物理学报》2005,54(11):4985-4988
研究完整力学系统Lie-形式不变性的定义与判据,给出由Lie-形式不变性导出的Noether守恒量,Hojman守恒量和Lutzky守恒量. 举例说明结果的应用. 关键词: 完整系统 Lie-形式不变性 Noether守恒量 Hojman守恒量 Lutzky守恒量  相似文献   

17.
相空间中二阶线性非完整系统的形式不变性   总被引:4,自引:1,他引:3       下载免费PDF全文
楼智美 《物理学报》2004,53(7):2046-2049
研究相空间中二阶线性非完整系统的形式不变性.给出相空间中二阶线性非完整系统形式不变性的定义和判据,得到形式不变性的结构方程和守恒量的形式,并举例说明结果的应用. 关键词: 相空间 二阶线性非完整系统 形式不变性 守恒量  相似文献   

18.
陈蓉  许学军 《物理学报》2012,61(2):21102-021102
研究变质量完整系统在无限小变换下的共形不变性与Noether对称性和Lie对称性.首先,给出了变质量完整系统的共形不变性的定义;其次,研究了系统的共形不变性与Noether对称性之间的关系,得到了共形不变性导致的Noether守恒量;最后,研究了系统的共形不变性与Lie对称性之间的关系,得到了共形不变性同时是Lie对称性导致的Hojman守恒量.最后举例说明了结果的应用.  相似文献   

19.
FORM INVARIANCE OF APPELL EQUATIONS   总被引:33,自引:0,他引:33       下载免费PDF全文
梅凤翔 《中国物理》2001,10(3):177-180
The form invariance of Appell equations of holonomic mechanical systems under the infinitesimal transformations of groups is studied. The definition and the criterion of the form invariance of Appell equations are given. This form invariance can lead to a conserved quantity under certain conditions.  相似文献   

20.
This paper studies the conformal invariance and conserved quantities of general holonomic systems in phase space. The definition and the determining equation of conformal invariance for general holonomic systems in phase space are provided. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The relationship between the conformal invariance and the Lie symmetry is discussed, and the necessary and sufficient condition that the conformal invariance would be the Lie symmetry of the system under the infinitesimal single-parameter transformation group is deduced. The conserved quantities of the system are given. An example is given to illustrate the application of the result.  相似文献   

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