Чаплыгин系统平衡状态的稳定性

考虑Чаплыгин系统平衡状态的稳定性，给出Чаплыгин系统的运动方程及其平衡状态的存在性条件，得到Чаплыгин系统平衡状态的一些稳定性判据，最后举例说明其应用。     

变质量非线性非完整系统相对于非惯性系的平衡状态的稳定性

首先，将变质量非线性非完整系统相对于非惯性系的运动问题当作一个有条件的完整系统问题来处理．其次，当系统存在平衡状态时，用一次近似方程来研究其相应完整系统平衡态的稳定性问题，如果一次近似方程是常系数的，其特征方程不可避免地会出现零根，零根的数目等于非完整约束方程的数目与完整系统平衡状态流形的维数之和，将这些零根简单地去掉，就可根据其它根是否有负实部来判断稳定性．最后，举例说明此方法的应用．     

广义Birkhoff自治系统的平衡稳定性

研究广义Ｂｉｒｋｈｏｆ自治系统的平衡稳定性问题·首先建立了广义Ｂｉｒｋｈｏｆ自治系统的平衡方程,然后研究平衡状态稳定性的一次近似方法和直接法,并应用Ляпунов定理得到了广义Ｂｉｒｋｈｏｆ自治系统平衡稳定性的一些结果·最后举例说明了这些结果的应用     

具有反应扩散项的变时滞复数域神经网络的指数稳定性

该文研究了一类具有反应扩散项的变时滞复数域神经网络的指数稳定性.首先在假设复数域激活函数可分解的情况下,将该系统分解为相应的实部系统和虚部系统.利用矢量Lyapunov函数法和M矩阵理论,得到了确保该系统平衡状态指数稳定性的充分条件.该条件不含有任何自由变量,相对现有结论具有较低的保守性.最后通过一个数值仿真算例验证了所得结论的正确性.     

电力系统渐近稳定域的估计

电力系统暂态稳定问题在远距离电力输送中意义格外重大。函数方法正是研究电力系统暂态稳定性的有力工具,近年来有不少人用直接方法研究这个问题,其中[1—3]用非线性系统绝对稳定性的Popov定理建立型的函数V(x),借助于这个函数估计围绕故障后系统平衡状态的渐近稳定域,即所谓吸引区域。现有的结果往往是保守的,因为由估计得到的渐近稳定域在实际的渐近稳定域之内。本文给出估计渐近稳定域的一种方法,它比[3]中方法更精确,因而也比[1—2]中的方法更精确。     

非线性球形薄膜的膨胀失稳

本文应用分支理论研究了非线性球形薄膜在轴对称大变形膨胀过程中的失稳问题.证明了所论非线性边值问题的奇点只能是单重极限点,并讨论了载荷和材料两个参数对球形薄膜平衡状态及其稳定性的影响.     

对一个课本习题解答的辨析

文[1]有如下问题： 如图1所示，一根绳子穿过两个定滑轮，且两端分别挂有3N，2N的重物，现在两个滑轮之间的绳上挂一个重量为mN的重物，恰好使得系统处于平衡状态，求正数m的取值范围．     

低维宏观交通流模型的稳定性和分岔分析

交通流模型的分岔点对应临界的交通状态,对研究交通流的稳定性具有重要的理论意义.为了分析宏观交通流模型的分岔特征,通过对低维宏观交通流模型的求解得到两个平衡点,并讨论了其稳定性,发现该模型存在一个跨临界分岔点.数值仿真验证了结论的正确性,并且在一定条件下,通过改变响应时间会影响到最终的平衡状态.     

一类非完整系统的Lagrange定理及其应用

本文研究一类非完整系统平衡位置流形的稳定性问题·利用Ляпунов直接法和稳定性定义将完整系统的Ｌａｇｒａｎｇｅ定理推广到一类非完整保守系统与耗散系统，并对该类非完整系统平衡位置流形的渐近稳定性与耗散力间的关系作了新的表述，最后举例说明定理的应用·     

马尔可夫跳跃双线性离散随机系统的稳定性

本研究了一类带有马尔可夫姚跃参数的双线性离散随机系统的稳定性，获得了该系统的稳定性和能稳定性的充分条件。     

Mac-Millan方程对非线性非完整力学系统的推广

本文首先将Mac-Millan方程推广到最一般的非完整力学系统,得到非线性非完整系统的广义Mac-Millan方程.其次,证明广义Mac-Millan方程与广义Чаплыгин方程的等价性,最后给出一个例子.     

Cone inequalities and stability of differential systems

We investigate generalizations of classes of monotone dynamical systems in a partially ordered Banach space. We establish algebraic conditions for the stability of equilibrium states of differential systems on the basis of linearization and application of derivatives of nonlinear operators with respect to a cone. Conditions for the positivity and absolute stability of a certain class of differential systems with delay are proposed. Several illustrative examples are given. Translated from Ukrains'kyi Matematychnyi Zhurnal, Vol. 60, No. 8, pp. 1058–1074, August, 2008.     

Stability of non-constant equilibrium solutions for two-fluid Euler–Maxwell systems

In this work we consider periodic problems for two-fluid compressible Euler–Maxwell systems for plasmas. The initial data are supposed to be in a neighborhood of non-constant equilibrium states. Mainly by an induction argument used in Peng (2015), we prove the global stability in the sense that smooth solutions exist globally in time and converge to the equilibrium states as the time goes to infinity. Moreover, we obtain the global stability of solutions with exponential decay in time near the equilibrium states for two-fluid compressible Euler–Poisson systems.     

Multiplicity and Stability of Equilibrium States of Three-Dimensional Nonlinear System

The multiplicity and stability of the equilibrium states of a three-dimensional differential system with initial conditions and three cross terms are studied in this paper. The existence and multiplicity of equilibrium states are given under the different qualifications of parameters. Besides, the local stability of the equilibrium state is shown by analyzing the eigenfunction of the Jacobi matrix. The global stability of the equilibrium state is obtained by constructing the Lyapunov function. Furthermore, the numerical simulation intuitively reflected the relationship of variables and verified the correctness of theoretical analysis.     

Thermodynamic Formalism and Multifractal Analysis of Conformal Infinite Iterated Function Systems

We develop the thermodynamic formalism for equilibrium states of strongly Hölder families of functions. These equilibrium states are supported on the limit set generated by iterating a system of infinitely many contractions. The theory of these systems was laid out in an earlier paper of the last two authors. The first five sections of this paper except Section 3 are devoted to developing the thermodynamic formalism for equilibrium states of Hölder families of functions. The first three sections provide us with the tools needed to carry out the multifractal analysis for the equilibrium states mentioned above assuming that the limit set is generated by conformal contractions. The theory of infinite systems of conformal contractions is laid out in [13]. The multifractal analysis is then given in Section 7. In Section 8 we apply this theory to some examples from continued fraction systems and Apollonian packing.     

Chaos and optimal control of cancer self-remission and tumor system steady states

This paper is devoted to study the problem of optimal control of cancer self-remission and tumor unstable steady-states. The stability analysis of the biologically feasible equilibrium states is presented using a local stability approach. The system appears exhibit a chaotic behavior for some ranges of the system parameters. The necessary optimal control inputs for the asymptotic stability of the positive equilibrium states and minimizes the require performance measure are obtained as nonlinear function of the system densities. Analysis and extensive numerical examples of the uncontrolled and controlled systems were carried out for various parameters values and different initial densities.     

The stability of systems with a delay at points on the boundaries of stability domains where safe sections become unsafe ones

The results obtained in [1–5] are applied to give a criterion for the stability of the equilibrium states of systems with a delay at points on the boundaries of stability domains where safe sections become unsafe.     

Unsafe and safe boundaries of the stability region of systems with delay in the case of a pair of pure imaginary roots and one zero root

A criterion of unsafe and safe parts of the boundary of stability regions of the equilibrium states of systems with delay, when the characteristic equation has a pair of pure imaginary roots and one zero root, is given, which develops results obtained previously in [1–6].     

Finite-time stabilization of nonlinear impulsive dynamical systems

Finite-time stability involves dynamical systems whose trajectories converge to a Lyapunov stable equilibrium state in finite time. For continuous-time dynamical systems finite-time convergence implies nonuniqueness of system solutions in reverse time, and hence, such systems possess non-Lipschitzian dynamics. For impulsive dynamical systems, however, it may be possible to reset the system states to an equilibrium state achieving finite-time convergence without requiring non-Lipschitzian system dynamics. In this paper, we develop sufficient conditions for finite-time stability of impulsive dynamical systems using both scalar and vector Lyapunov functions. Furthermore, we design hybrid finite-time stabilizing controllers for impulsive dynamical systems that are robust against full modelling uncertainty. Finally, we present a numerical example for finite-time stabilization of large-scale impulsive dynamical systems.     

On the gyroscopic stabilization of conservative systems

We consider conservative systems with gyroscopic forces and prove theorems on stability and instability of equilibrium states for such systems. These theorems can be regarded as a generalization of the Kelvin theorem to nonlinear systems.