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Integrating Factors and Conservation Laws of Herglotz Type for Birkhoffian Systems
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作者 WANG Wenjing ZHANG Yi 《Wuhan University Journal of Natural Sciences》 2025年第1期49-56,共8页
The method of integrating factors is used to study the conservation laws of the Herglotz type Birkhoffian systems in this paper.Firstly,the definition of the integrating factors of the Herglotz type Birkhoffian system... The method of integrating factors is used to study the conservation laws of the Herglotz type Birkhoffian systems in this paper.Firstly,the definition of the integrating factors of the Herglotz type Birkhoffian systems is given.Secondly,the relationship between the integrating factors and conservation laws is studied,and the conservation theorems of Herglotz type Birkhoff's equations and their inverse theorems are established.Thirdly,two types of generalized Killing equations for calculating integrating factors are given.Finally,as an example,a linear damped oscillator is taken.This example can be transformed into a Herglotz type Birkhoffian system.The resulting conservation theorems are used to find the conserved quantities for this example. 展开更多
关键词 birkhoffian system Herglotz's variational principle integrating factors conservation law
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Perturbation to Symmetries and Adiabatic Invariants for Generalized Birkhoffian Systems on Time Scales 被引量:2
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作者 HOU Shuang SONG Chuanjing 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2024年第3期263-272,共10页
Time scale is a new and powerful tool for dealing with complex dynamics problems. The main result of this study is the exact invariants and adiabatic invariants of the generalized Birkhoffian system and the constraine... Time scale is a new and powerful tool for dealing with complex dynamics problems. The main result of this study is the exact invariants and adiabatic invariants of the generalized Birkhoffian system and the constrained Birkhoffian system on time scales. Firstly, we establish the differential equations of motion for the above two systems and give the corresponding Noether symmetries and exact invariants. Then, the perturbation to the Noether symmetries and the adiabatic invariants for the systems mentioned above under the action of slight disturbance are investigated, respectively. Finally, two examples are provided to show the practicality of the findings. 展开更多
关键词 time scale generalized birkhoffian system Noether symmetry perturbation and adiabatic invariants
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Method of variation of parameters for solving a constrained Birkhoffian system
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作者 张毅 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期342-345,共4页
For an in-depth study on the integration problem of the constrained mechanical systems the method of integration for the Birkhoffian system with constraints is discussed and the method of variation of parameters for s... For an in-depth study on the integration problem of the constrained mechanical systems the method of integration for the Birkhoffian system with constraints is discussed and the method of variation of parameters for solving the dynamical equations of the constrained Birkhoffian system is provided.First the differential equations of motion for the constrained Birkhoffian system as well as for the corresponding free Birkhoffian system are established.Secondly a system of auxiliary equations is constructed and the general solution of the equations is found.Finally by varying the parameters and utilizing the properties of the generalized canonical transformation of the Birkhoffian system the solution of the problem can be obtained.The proposed method reveals the inherent relationship between the solution of a free Birkhoffian system and that of a constrained Birkhoffian system. The research results are of universal significance which can be further used in a variety of constrained mechanical systems such as non-conservative systems and nonholonomic systems etc. 展开更多
关键词 birkhoffian mechanics method of integration method of variation of parameter constrained birkhoffian system
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Form Invariance of Birkhoffian Systems 被引量:4
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作者 梅凤翔 陈向炜 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期138-142,共5页
The form invariance of Birkhoffian systems is a kind of invariance of the Birkhoffian equations under the infinitesimal transformations. The definition and criteria of the form invariance are given, and the relation b... The form invariance of Birkhoffian systems is a kind of invariance of the Birkhoffian equations under the infinitesimal transformations. The definition and criteria of the form invariance are given, and the relation between the form invariance and the Noether symmetry is studied. 展开更多
关键词 birkhoffian system form invariance Noether symmetry
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Symmetries and conserved quantities of generalized Birkhoffian systems 被引量:3
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作者 张毅 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期146-150,共5页
Three kinds of symmetries and their corresponding conserved quantities of a generalized Birkhoffian system are studied. First, by using the invariance of the Pfaffian action under the infinitesimal transformations, th... Three kinds of symmetries and their corresponding conserved quantities of a generalized Birkhoffian system are studied. First, by using the invariance of the Pfaffian action under the infinitesimal transformations, the Noether theory of the generalized Birkhoffian system is established. Secondly, on the basis of the invariance of differential equations under infinitesimal transformations, the definition and the criterion of the Lie symmetry of the generalized Birkhoffian system are established, and the Hojman conserved quantity directly derived from the Lie symmetry of the system is given. Finally, by using the invariance that the dynamical functions in the differential equations of the motion of mechanical systems still satisfy the equations after undergoing the infinitesimal transformations, the definition and the criterion of the Mei symmetry of the generalized Birkhoffian system are presented, and the Mei conserved quantity directly derived from the Mei symmetry of the system is obtained. Some examples are given to illustrate the application of the results. 展开更多
关键词 generalized birkhoffian system SYMMETRY conserved quantity
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A new method for integration of a Birkhoffian system 被引量:1
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作者 张毅 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期188-191,共4页
The idea of the gradient method for integrating the dynamical equations of a nonconservative system presented by Vujanovic is transplanted to a Birkhoffian system, which is a new method for the integration of Birkhoff... The idea of the gradient method for integrating the dynamical equations of a nonconservative system presented by Vujanovic is transplanted to a Birkhoffian system, which is a new method for the integration of Birkhoff's equations. First, the differential equations of motion of the Birkhoffian system are written out. Secondly, 2n Birkhoff's variables are divided into two parts, and assume that a part of the variables is the functions of the remaining part of the variables and time. Thereby, the basic quasi-linear partial differential equations are established. If a complete solution of the basic partial differential equations is sought out, the solution of the problem is given by a set of algebraic equations. Since one can choose n arbitrary Birkhoff's variables as the functions of n remains of variables and time in a specific problem, the method has flexibility. The major difficulty of this method lies in finding a complete solution of the basic partial differential equation. Once one finds the complete solution, the motion of the systems can be obtained without doing further integration. Finally, two examples are given to illustrate the application of the results. 展开更多
关键词 birkhoffian system integration method basicpartial differential equation
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The Noether's Theory of Constrained Birkhoffian System
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作者 尚玫 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期221-228,共8页
By using the synmeby and the qusi-symmetry of the infinitesimal transformation of the transformation group G1 and by imposing restrictions of constraints on the transformation, the Noether's theory of constrained ... By using the synmeby and the qusi-symmetry of the infinitesimal transformation of the transformation group G1 and by imposing restrictions of constraints on the transformation, the Noether's theory of constrained Birkhoffian system has been established. The theory includes the generalized Noether's theorem obtaining the first integrals from the known symmetry and quasi-symmetry and its inverse obtaining the corresponding symmetry and quasi-symmetry from the known first integrals for the systerm. 展开更多
关键词 .birkhoffian system: constraint TRANSFORMATION conservation law Noether's theorem
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非线性非保守系统的近似Birkhoffian化
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作者 姜文安 夏丽莉 《江苏科技大学学报(自然科学版)》 CAS 2019年第1期121-123,130,共4页
研究了非线性非保守动力学系统的近似Birkhoffian化.基于等效线性化方法,通过平方误差累积最优原理,给出了非线性非保守系统的等效线性化系统.运用Santilli第一方法,得到Birkhoff函数为系统总能量的近似Birkhoff系统.最后,应用文中提出... 研究了非线性非保守动力学系统的近似Birkhoffian化.基于等效线性化方法,通过平方误差累积最优原理,给出了非线性非保守系统的等效线性化系统.运用Santilli第一方法,得到Birkhoff函数为系统总能量的近似Birkhoff系统.最后,应用文中提出的方法,给出了两类非线性非保守系统的近似Birkhoffian方程. 展开更多
关键词 非保守系统 birkhoffian 等效线性化方法
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Structure-preserving algorithms for autonomous Birkhoffian systems
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作者 孔新雷 吴惠彬 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 2012年第1期1-7,共7页
The Pfaff-Birkhoff variational principle is discretized, and based on the discrete variational principle the discrete Birkhoffian equations are obtained. Taking the discrete equations as an algorithm, the correspondin... The Pfaff-Birkhoff variational principle is discretized, and based on the discrete variational principle the discrete Birkhoffian equations are obtained. Taking the discrete equations as an algorithm, the corresponding discrete flow is proved to be symplectic. That means the algorithm preserves the symplectic structure of Birkhofflan systems. Finally, simulation results of the given example indicate that structure-preserving algorithms have great advantage in stability and energy conserving. 展开更多
关键词 birkhoffian system discrete birkhoffian equations structure-preserving algorithm
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First Integrals and Reduction of the Birkhoffian System 被引量:5
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作者 郑改华 陈向炜 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期17-22,共6页
Refer to the Hamiltonian system, first integrals of the Birkhoffian system can be found by using of the perfect differential method. Through these first integrals, the order of the Birkhoffian system can be reduced. T... Refer to the Hamiltonian system, first integrals of the Birkhoffian system can be found by using of the perfect differential method. Through these first integrals, the order of the Birkhoffian system can be reduced. Then according to the alternate of the coordinate, a kind of new partial differential operator was defined in order to hold the Birkhoff form. The result shows that the Birkhoffian system has generalized energy integrals and cyclic integrals. Furthermore, each integral can reduce the order of equations two degrees. 展开更多
关键词 birkhoffian system first integral generalized energy integral cyclic integral REDUCTION
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Noether's theorems of a fractional Birkhoffian system within Riemann-Liouville derivatives 被引量:17
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作者 周燕 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期281-288,共8页
The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding ... The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding transversality conditions are given. Secondly, from special to general forms, Noether's theorems of a standard Birhoffian system are given, which provide an approach and theoretical basis for the further research on the Noether symmetry of the fractional Birkhoffian system. Thirdly, the invariances of the fractional Pfaffian action under a special one-parameter group of infinitesimal transformations without transforming the time and a general one-parameter group of infinitesimal transformations with transforming the time are studied, respectively, and the corresponding Noether's theorems are established. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 fractional birkhoffian system Noether's theorem fractional conserved quantity Riemann–Liouville fractional derivative
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Bifurcation for the generalized Birkhoffian system 被引量:7
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作者 梅凤翔 吴惠彬 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期419-420,共2页
The system described by the generalized Birkhoff equations is called a generalized Birkhoffian system. In this paper, the condition under which the generalized Birkhoffian system can be a gradient system is given. The... The system described by the generalized Birkhoff equations is called a generalized Birkhoffian system. In this paper, the condition under which the generalized Birkhoffian system can be a gradient system is given. The stability of equilibrium of the generalized Birkhoffian system is discussed by using the properties of the gradient system. When there is a parameter in the equations, its influences on the stability and the bifurcation problem of the system are considered. 展开更多
关键词 generalized birkhoffian system gradient system STABILITY BIFURCATION
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Skew-gradient representation of generalized Birkhoffian system 被引量:7
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作者 梅凤翔 吴惠彬 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期312-314,共3页
The skew-gradient representation of a generalized Birkhoffian system is studied. A condition under which the generalized Birkhoffian system can be considered as a skew-gradient system is obtained. The properties of th... The skew-gradient representation of a generalized Birkhoffian system is studied. A condition under which the generalized Birkhoffian system can be considered as a skew-gradient system is obtained. The properties of the skew-gradient system are used to study the properties, especially the stability, of the generalized Birkhoffian system. Some examples are given to illustrate the application of the result. 展开更多
关键词 generalized birkhoffian system skew-gradient system Lyapunov function STABILITY
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Generalized canonical transformation for second-order Birkhoffian systems on time scales 被引量:5
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作者 Y.Zhang X.H.Zhai 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期353-357,共5页
The theory of time scales,which unifies continuous and discrete analysis,provides a powerful mathematical tool for the study of complex dynamic systems.It enables us to understand more clearly the essential problems o... The theory of time scales,which unifies continuous and discrete analysis,provides a powerful mathematical tool for the study of complex dynamic systems.It enables us to understand more clearly the essential problems of continuous systems and discrete systems as well as other complex systems.In this paper,the theory of generalized canonical transformation for second-order Birkhoffian systems on time scales is proposed and studied,which extends the canonical transformation theory of Hamilton canonical equations.First,the condition of generalized canonical transformation for the second-order Birkhoffian system on time scales is established.Second,based on this condition,six basic forms of generalized canonical transformation for the second-order Birkhoffian system on time scales are given.Also,the relationships between new variables and old variables for each of these cases are derived.In the end,an example is given to show the application of the results. 展开更多
关键词 birkhoffian systems GENERALIZED CANONICAL transformation Time scales CALCULUS Generating function
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Poisson theory and integration method of Birkhoffian systems in the event space 被引量:6
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作者 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期80-84,共5页
This paper focuses on studying the Poisson theory and the integration method of a Birkhoffian system in the event space. The Birkhoff's equations in the event space are given. The Poisson theory of the Birkhoffian sy... This paper focuses on studying the Poisson theory and the integration method of a Birkhoffian system in the event space. The Birkhoff's equations in the event space are given. The Poisson theory of the Birkhoffian system in the event space is established. The definition of the Jacobi last multiplier of the system is given, and the relation between the Jacobi last multiplier and the first integrals of the system is discussed. The researches show that for a Birkhoffian system in the event space, whose configuration is determined by (2n + 1) Birkhoff's variables, the solution of the system can be found by the Jacobi last multiplier if 2n first integrals are known. An example is given to illustrate the application of the results. 展开更多
关键词 birkhoffian system event space method of integration Jacobi last multiplier
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Conservation laws for Birkhoffian systems of Herglotz type 被引量:6
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作者 Yi Zhang Xue Tian 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期223-229,共7页
Conservation laws for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are studied. We propose a new differential variational principle, called the Pfaff-Birkhoff-d'Alembert principle of... Conservation laws for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are studied. We propose a new differential variational principle, called the Pfaff-Birkhoff-d'Alembert principle of Herglotz type. Birkhoff's equations for both the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are obtained. According to the relationship between the isochronal variation and the nonisochronal variation, the conditions of the invariance for the Pfaff-Birkhoff-d'Alembert principle of Herglotz type are given. Then, the conserved quantities for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are deduced. Furthermore, the inverse theorems of the conservation theorems are also established. 展开更多
关键词 birkhoffian system conversation law differential variational principle variational problem of Herglotz type
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Stability of Motion for Generalized Birkhoffian Systems 被引量:5
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作者 张毅 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第3期161-165,共5页
The problem on the stability of motion for a generalized Birkhoffian system was studied. The disturbed equations of motion and their first approximation for the system were established. The criterion of stability of m... The problem on the stability of motion for a generalized Birkhoffian system was studied. The disturbed equations of motion and their first approximation for the system were established. The criterion of stability of motion for the system was set up by using Liapunov's first approximation theory. Based on the theory of Noether symmetry,the Liapunov's function was constructed,and the criterion of stability of motion for the system was also set up by using Liapunov's direct method. Two examples were given to illustrate the application of the results. 展开更多
关键词 applied mathematics generalized birkhoffian system stability of motion Noether symmetry
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Routh Order Reduction Method of Relativistic Birkhoffian Systems 被引量:3
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作者 LUO Shao-Kai GUO Yong-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期209-212,共4页
Routh order reduction method of the relativistic Birkhoffian equations is studied. For a relativistic Birkhoffian system, the cyclic integrals can be found by using the perfect differential method. Through these cycli... Routh order reduction method of the relativistic Birkhoffian equations is studied. For a relativistic Birkhoffian system, the cyclic integrals can be found by using the perfect differential method. Through these cyclic integrals, the order of the system can be reduced. If the relativistic Birkhoffian system has a cyclic integral, then the Birkhoffian equations can be reduced at least by two degrees 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 Routh order reduction method of the relativistic Lagrangian system is obtained. And an example is given to illustrate the application of the result. 展开更多
关键词 RELATIVITY birkhoffian system Lagrangian system cyclic integral order reduction method
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Conserved quantities and adiabatic invariants of fractional Birkhoffian system of Herglotz type 被引量:4
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作者 Juan-Juan Ding Yi Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期303-311,共9页
In order to further study the dynamical behavior of nonconservative systems,we study the conserved quantities and the adiabatic invariants of fractional Brikhoffian systems with four kinds of different fractional deri... In order to further study the dynamical behavior of nonconservative systems,we study the conserved quantities and the adiabatic invariants of fractional Brikhoffian systems with four kinds of different fractional derivatives based on Herglotz differential variational principle.Firstly,the conserved quantities of Herglotz type for the fractional Brikhoffian systems based on Riemann-Liouville derivatives and their existence conditions are established by using the fractional Pfaff-Birkhoff-d Alembert principle of Herglotz type.Secondly,the effects of small perturbations on fractional Birkhoffian systems are studied,the conditions for the existence of adiabatic invariants for the Birkhoffian systems of Herglotz type based on Riemann-Liouville derivatives are established,and the adiabatic invariants of Herglotz type are obtained.Thirdly,the conserved quantities and adiabatic invariants for the fractional Birkhoffian systems of Herglotz type under other three kinds of fractional derivatives are established,namely Caputo derivative,Riesz-Riemann-Liouville derivative and Riesz-Caputo derivative.Finally,an example is given to illustrate the application of the results. 展开更多
关键词 FRACTIONAL birkhoffian system Pfaff-Birkhoff-d’Alembert PRINCIPLE ADIABATIC invariant Herglotz generalized VARIATIONAL PRINCIPLE
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Perturbation to Mei symmetry and Mei adiabatic invariants for discrete generalized Birkhoffian system 被引量:3
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作者 张克军 方建会 李燕 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第5期305-309,共5页
Based on the concept of discrete adiabatic invariant, this paper studies the perturbation to Mei symmetry and Mei adiabatic invariants of the discrete generalized Birkhoffian system. The discrete Mei exact invariant i... Based on the concept of discrete adiabatic invariant, this paper studies the perturbation to Mei symmetry and Mei adiabatic invariants of the discrete generalized Birkhoffian system. The discrete Mei exact invariant induced from the Mei symmetry of the system without perturbation is given. The criterion of the perturbation to Mei symmetry is established and the discrete Mei adiabatic invariant induced from the perturbation to Mei symmetry is obtained. Meanwhile, an example is discussed to illustrate the application of the results. 展开更多
关键词 discrete generalized birkhoffian system Mei symmetry PERTURBATION Mei adiabatic in-variant
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