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1.
The notion of a generalized Lie bialgebroid (a generalization of the notion of a Lie bialgebroid) is introduced in such a way that a Jacobi manifold has associated a canonical generalized Lie bialgebroid. As a kind of converse, we prove that a Jacobi structure can be defined on the base space of a generalized Lie bialgebroid. We also show that it is possible to construct a Lie bialgebroid from a generalized Lie bialgebroid and, as a consequence, we deduce a duality theorem. Finally, some special classes of generalized Lie bialgebroids are considered: triangular generalized Lie bialgebroids and generalized Lie bialgebras.  相似文献   

2.
李彦敏  陈向炜  吴惠彬  梅凤翔 《物理学报》2016,65(8):80201-080201
提出了两类广义梯度系统, 即广义斜梯度系统以及具有对称负定矩阵的广义梯度系统. 分别讨论了这两类梯度系统与动力学系统稳定性的关系. 研究了广义Brikhoff系统的两类广义梯度表示, 分别给出条件和表达式. 给出了广义Brikhoff系统稳定性的梯度判别法, 利用广义梯度系统的性质来研究广义Birkhoff系统的稳定性. 并举例说明了方法的应用.  相似文献   

3.
A new approach to the construction of a system of the generalized radiometric quantities expressed in terms of the cross-spectral density function of the wave field is proposed. The key distinction of this approach lies in the fact that the initial hypothesis of beamlike wave propagation allows to invoke the paraxial approximation when deducing the generalized radiant flux. Within the framework of this approach the new expressions for the generalized radiant emittance, the generalized radiant intensity and the generalized radiance are derived. All the proposed generalized radiometric characteristics represent physically measurable quantities and, hence, may be used in practical radiometry. The results obtained in this paper can be regarded as a particular case of the modern radiometry theory in paraxial approximation for beamlike wave propagation.On leave from Kiev Polytechnic Institute, Ukraine.  相似文献   

4.
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.  相似文献   

5.
R.C. Venkatesan  A. Plastino 《Physica A》2011,390(15):2749-2758
There exist two different versions of the Kullback-Leibler divergence (K-Ld) in Tsallis statistics, namely the usual generalized K-Ld and the generalized Bregman K-Ld. Problems have been encountered in trying to reconcile them. A condition for consistency between these two generalized K-Ld forms is derived by recourse to the additive duality of Tsallis statistics. It is also shown that the usual generalized K-Ld subjected to this additive duality, known as the dual generalized K-Ld, is a scaled Bregman divergence. This leads to an interesting conclusion: the dual generalized mutual information is a scaled Bregman information. The utility and implications of these results are discussed.  相似文献   

6.
We investigate generalized holomorphic structures in generalized complex geometry. We find that a generalized holomorphic vector bundle carries a generalized complex structure on its total space if some additional conditions hold. We prove that generalized holomorphicity is equivalent to the integrability of a distribution on the total space, and a family of linear Dirac structures associated with this distribution is a generalized complex structure if a further condition holds. Under the same condition, we also prove that local generalized holomorphic frames exist around a regular point.  相似文献   

7.
Constrained quantum dynamics is used to propose a nonlinear dynamical equation for pure states of a generalized coarse-grained system. The relevant constraint is given either by the generalized purity or by the generalized invariant fluctuation, and the coarse-grained pure states correspond to the generalized coherent, i.e. generalized nonentangled states. Open system model of the coarse-graining is discussed. It is shown that in this model and in the weak coupling limit the constrained dynamical equations coincide with an equation for pointer states, based on Hilbert-Schmidt distance, that was previously suggested in the context of the decoherence theory.  相似文献   

8.
约束系统的变换和推广的Killing方程   总被引:2,自引:0,他引:2       下载免费PDF全文
李子平 《物理学报》1984,33(6):814-825
本文从约束系统的作用量和约束方程的普遍变换性质出发,得到了约束系统的推广Killing方程组,此方程组的解所生成的变换可产生经典Noether定理的守恒量。讨论了连续系统的时空变换和内禀变换,在变换保持约束方程不变时,指出此变换能导致守恒流的充要条件,给出了对不可压缩连续介质的应用,讨论了对广义力学和经典力学的应用,并给出了推广Killing方程组解的某些实例,将Poincare不变量推广到了受约束广义力学系统。 关键词:  相似文献   

9.
This paper generalizes the control and synchronization of chaotic dynamics in resistive–capacitive–inductive-shunted Josephson junction (RCLSJ) models via the backstepping nonlinear control theory. The method, which consists in a recursive approach that interlaces the choice of a Lyapunov function with the control, is used to design a generalized control function that is capable of controlling the chaotic dynamics exhibited by RCLSJ model to track desired dynamics. The result suggests that the generalized controller could be used as a device for tuning the junction signal into any desired form. The active backstepping technique is used to design a single control function that achieves generalized projective synchronization between two RCLSJ systems evolving from different initial conditions. This result suggests that the controller for generalized projective synchronization could be used to amplify the junction signal. Numerical simulation results show that the generalized control functions are effective in both the tracking control and generalized projective synchronization of RCLSJ models.  相似文献   

10.
We present a generalized convolution theorem in the fractional Fourier domains that preserves the convolution theorem of the conventional Fourier transform. The Papoulis-like generalized sampling expansions in the fractional Fourier domains using this generalized convolution theorem are also derived and it is shown that the classical generalized Papoulis sampling expansion is a special case of it. Its application in the context of the image superresolution is also discussed.  相似文献   

11.
A novel conception and its applications, the generalized metric for correlation fringes, are presented, which can be used to develop and analyze the relevant algorithms. The relationship between the metric and the correlation fringes representation is examined and the generalized metric is defined. The theoretical analysis of traditional algorithms for correlation fringes indicates that all of them can be regarded as the generalized metrics. In addition, the generalized metric for correlation fringes is applied in developing a new algorithm. A novel generalized metric for correlation fringes based on cross entropy is presented and is proved by theoretical derivation and experimental verification. All the investigations show that it is reasonable and valid to define the generalized metric for correlation fringes in digital speckle pattern interferometry (DSPI). The fringes obtained by cross-entropy metric can be used to represent the same desired information by subtracting. There are different vector function structures among the generalized metrics, which directly influence the quality of fringes and the difficulty in post-processing.  相似文献   

12.
The generalized Kullback-Leibler divergence (K-Ld) in Tsallis statistics [constrained by the additive duality of generalized statistics (dual generalized K-Ld)] is here reconciled with the theory of Bregman divergences for expectations defined by normal averages, within a measure-theoretic framework. Specifically, it is demonstrated that the dual generalized K-Ld is a scaled Bregman divergence. The Pythagorean theorem is derived from the minimum discrimination information principle using the dual generalized K-Ld as the measure of uncertainty, with constraints defined by normal averages. The minimization of the dual generalized K-Ld, with normal averages constraints, is shown to exhibit distinctly unique features.  相似文献   

13.
A simplified method for the free vibration and flutter analysis of bridge decks is presented. Bending-torsion coupled beam theory with warping stiffness included is used in the structural idealization of bridge decks in order to derive explicit formulae for natural frequencies and mode shapes. These are used to perform the flutter analysis. The time-dependent aerodynamic forces are modelled using Theodorsen type flat plate theory. Expressions for generalized mass, generalized stiffness and generalized aerodynamic force terms are derived in compact explicit form. The flutter problem is then formulated by summing algebraically the analytical expressions for generalized mass, generalized stiffness and generalized aerodynamic forces, and the associated flutter determinant is expanded in analytical form. Finally, the flutter speed and flutter frequency are thereby determined by using a standard root finding procedure. The method is demonstrated by numerical results. This is followed by some concluding remarks.  相似文献   

14.
贾利群  孙现亭  张美玲  张耀宇  韩月林 《物理学报》2014,63(1):10201-010201
研究相对运动变质量完整系统Appell方程的广义Lie对称性及其直接导致的广义Hojman守恒量.在群的无限小变换下,给出相对运动变质量完整系统Appell方程广义Lie对称性的确定方程;得到相对运动变质量完整系统Appell方程广义Lie对称性直接导致的广义Hojman守恒量的表达式.最后,利用本文结果研究相对运动变质量完整约束的三自由度力学系统问题.  相似文献   

15.
In this paper, we construct Hamiltonian systems for 2 N particles whose force depends on the distances between the particles. We obtain the generalized finite nonperiodic Toda equations via a symmetric group transformation. The solutions of the generalized Toda equations are derived using the tau functions. The relationship between the generalized nonperiodic Toda lattices and Lie algebras is then be discussed and the generalized Kac-van Moerbeke hierarchy is split into generalized Toda lattices, whose integrability and Darboux transformation are studied.  相似文献   

16.
Jun Li  Lingen Chen  Fengrui Sun 《Pramana》2010,74(2):219-230
The fundamental optimal relation between heating load and coefficient of performance (COP) of a generalized irreversible Carnot heat pump is derived based on a new generalized heat transfer law, which includes the generalized convective heat transfer law and generalized radiative heat transfer law, q ∝ (ΔT n ) m . The generalized irreversible Carnot heat pump model incorporates several internal and external irreversibilities, such as heat resistance, bypass heat leakage, friction, turbulence and other undesirable irreversibility factors. The added irreversibilities besides heat resistance are characterized by a constant parameter and a constant coefficient. The effects of heat transfer laws and various loss terms are analysed. The heating load vs. COP characteristic of a generalized irreversible Carnot heat pump is a parabolic-like curve, which is consistent with the experimental result of thermoelectric heat pump. The obtained results include those obtained in many literatures and indicated that the analysis results of the generalized irreversible Carnot heat pump were more suitable for engineering practice than those of the endoreversible Carnot heat pump.  相似文献   

17.
A new generalized solitary solution of the Jaulent-Miodek equations is obtained using the Exp-function method. By a transformation, the solitary solution can be easily converted into a generalized compacton-like solution. The free parameters in the obtained generalized solutions might imply some meaningful results in physical process.  相似文献   

18.
截断光束的广义M2因子   总被引:2,自引:0,他引:2       下载免费PDF全文
罗时荣  吕百达  孙年春 《物理学报》2004,53(7):2145-2149
使用渐近分析法、广义截断二阶矩法和自收敛束宽法研究了旋转对称截断光束的广义M2因子,分析了这三种方法的物理联系以及如何惟一确定广义M2因子问题,并用数值计算结果做了说明. 关键词: 广义M2因子 渐近分析 广义截断二阶矩法 自收敛束宽  相似文献   

19.
李农  李建芬 《物理学报》2011,60(11):110512-110512
提出一种实现混沌系统投影同步的统一方法.通过构建一个广义比例矩阵和一个合适的响应系统,建立了混沌投影同步的通用模型,依据比例矩阵的不同种类,可实现广义投影同步、错位投影同步和广义混合错位投影同步等各种类型的混沌投影同步.利用Lyapunov稳定性理论给出了相应的证明,最后以多卷波混沌系统和超混沌Qi系统为例,进行了错位投影同步和广义混合错位投影同步的数值仿真,仿真结果进一步表明了该方法的有效性. 关键词: 混沌系统 广义比例矩阵 统一投影同步  相似文献   

20.
截断光束的广义M2因子   总被引:1,自引:0,他引:1       下载免费PDF全文
使用渐近分析法、广义截断二阶矩法和自收敛束宽法研究了旋转对称截断光束的广义M2 因子 ,分析了这三种方法的物理联系以及如何惟一确定广义M2 因子问题 ,并用数值计算结果做了说明 .  相似文献   

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