一类非线性时滞差分方程的稳定性

得到了一类线性非自治时滞差分方程的零解的一致稳定、一致渐近稳定和全局渐近稳定的充分条件.     

一类弱稳定的Banach空间

为了解决什么样的Ｂａｎａｃｈ空间，它的每个无穷维子空间几乎等距地含有Ｃ０或ｌｐ（１≤ｐ＜∞）问题，Ｊ．Ｌ．Ｋｒｉｖｉｎｅ１９７９年在［４］中引进了稳定的Ｂａｎａｃｈ空间的概念．Ｓ．Ａｒｇｙｏｒｓ．在［２］中引进了弱稳定的概念，列举了一个弱稳定而非稳定的Ｂａｎａｃｈ空间，本文引进具有Ｐ－凸完备极小系的Ｂａｎａｃｈ空间，证明了该空间是弱稳定以及可赋等价的稳定范数的充要条件是其自反．最后给出了不自反的具有Ｐ—凸完备极小系的Ｂａｎａｃｈ空间的例子从而推广了［２］中结果．     

具有扰动的非自治中立型泛函微分方程的渐近稳定性

本文讨论了具有扰动的非自治中立型泛函微分方程的3/2-稳定性,得到了零解一致稳定和渐近稳定的充分条件.     

隐稳定的充分条件

本文分析隐稳定矩阵的充分条件，得到几个关于低阶隐稳定矩阵扩充高阶后仍保持隐稳定的结果．     

幂稳定自由模范畴及其K0群

引进了稳定自由阶、稳定自由秩及幂稳定同构的概念.由此,通过一条新的途径,研究了环(不必可换)的幂稳定自由模范畴以及IBN(不变基数)环(不必可换)的幂稳定自由模范畴的K₀群的结构.推广了一些相关的结果.     

一类非线性动力系统实用稳定域的研究及应用

借助于李雅普诺夫函数讨论了一类非线性动力系统的实用稳定性和实用稳定域的估计问题,得到了实用稳定域存在的充分条件,给出了一类动力系统实用稳定域的具体形式.通过具体实例说明了所给条件的实用性,改进了已有的结果.     

迹稳定秩1的C~*-代数的稳定有限性与弱迹稳定秩1

主要给出了迹稳定秩1的C~*-代数的稳定有限性,证明了如果A是有单位元迹稳定秩1的C~*-代数,则A是稳定有限的,引入了弱迹稳定秩1的定义,并且证明了如果有单位元的C~*-代数A是迹稳定秩1的,则A是弱迹稳定秩1的．对于单的具有SP性质的有单位元的C~*-代数A,如果A是弱迹稳定秩1的,则A是迹稳定秩1的．同时给出了迹稳定秩1的C~*-代数的一个等价条件,证明了一个有单位元的可分的C~*-代数A是迹稳定秩1的,等价于A=(t_4)limn→∞(A_n,p_n),其中tsr(A_n)=1．     

迹稳定秩1的C*-代数的稳定有限性与弱迹稳定秩1

主要给出了迹稳定秩1的C*-代数的稳定有限性,证明了如果A是有单位元迹稳定秩1的C*-代数,则A是稳定有限的,引入了弱迹稳定秩1的定义,并且证明了如果有单位元的C*-代数A是迹稳定秩1的,则A是弱迹稳定秩1的.对于单的具有SP性质的有单位元的C*-代数A,如果A是弱迹稳定秩1的,则A是迹稳定秩1的.同时给出了迹稳定秩1的C*-代数的一个等价条件,证明了一个有单位元的可分的C*-代数A是迹稳定秩1的,等价于A=(t4)limn→∞(An,Pn),其中tsr(AN)=1.     

单的迹稳定秩一C*-代数的消去性质

本文证明了一个单的有单位元的迹稳定秩一的C*-代数具有消去律,利用此结果证明了单的有单位元的迹稳定秩一的C*-代数是稳定秩一的.最后讨论了迹稳定秩一的C*-代数的K0群的性质.     

带势的非线性Klein-Gordon方程柯西问题的稳定和不稳定集

对带势的非线性Klein-Gordon方程柯西问题,我们定义了新的对于初值的稳定和不稳定集.我们证明了如果发展进入了不稳定集,解在有限时间内爆破;如果发展进入了稳定集,解整体存在.运用势并讨论,我们回答了当初值为多少时,柯西问题的整体解存在.     

具有扰动项的n维Volterra型积分微分方程的稳定性

讨论具有扰动项的n维Volterra积分微分方程.x=A(x)x(t)+∫t0C(t,s)x(s)ds+f(t,x(t))零解的稳定性及一致稳定性,得到零解稳定和一致稳定的若干充分判据.     

正负系数的扰动的中立型微分方程的稳定性

In this paper the perturbed neutral differential equation with positive and negative coefficients d/dt[x(t)-C(t)x(t-r)] p(t)x(t-x)-Q(t)x(t-δ)=f(t,x(t)),t≥t0is considered. Sufficient conditions for the zero solution of this equation to be uniformly stable as well as asymptotically stable are obtained.     

ASYMPTOTIC STABILITY FOR A CLASS OF NONAUTONOMOUS NEUTRAL DIFFERENTIAL EQUATIONS

ＡＳＹＭＰＴＯＴＩＣＳＴＡＢＩＬＩＴＹＦＯＲＡＣＬＡＳＳＯＦＮＯＮＡＵＴＯＮＯＭＯＵＳＮＥＵＴＲＡＬＤＩＦＦＥＲＥＮＴＩＡＬＥＱＵＡＴＩＯＮＳ＊＊ＹＵＪＩＡＮＳＨＥ＊ＭａｎｕｓｃｒｉｐｔｒｅｃｅｉｖｅｄＪｕｌｙ４，１９９５．ＲｅｖｉｓｅｄＭａｒｃｈ２...     

Stability of functional equations in single variable

This paper discusses Hyers-Ulam stability for functional equations in single variable, including the forms of linear functional equation, nonlinear functional equation and iterative equation. Surveying many known and related results, we clarify the relations between Hyers-Ulam stability and other senses of stability such as iterative stability, continuous dependence and robust stability, which are used for functional equations. Applying results of nonlinear functional equations we give the Hyers-Ulam stability of Böttcher's equation. We also prove a general result of Hyers-Ulam stability for iterative equations.     

Orbital stability of solitary waves for Kundu equation

In this paper, we consider the Kundu equation which is not a standard Hamiltonian system. The abstract orbital stability theory proposed by Grillakis et al. (1987, 1990) cannot be applied directly to study orbital stability of solitary waves for this equation. Motivated by the idea of Guo and Wu (1995), we construct three invariants of motion and use detailed spectral analysis to obtain orbital stability of solitary waves for Kundu equation. Since Kundu equation is more complex than the derivative Schrödinger equation, we utilize some techniques to overcome some difficulties in this paper. It should be pointed out that the results obtained in this paper are more general than those obtained by Guo and Wu (1995). We present a sufficient condition under which solitary waves are orbitally stable for 2c₃+s₂υ<0, while Guo and Wu (1995) only considered the case 2c₃+s₂υ>0. We obtain the results on orbital stability of solitary waves for the derivative Schrödinger equation given by Colin and Ohta (2006) as a corollary in this paper. Furthermore, we obtain orbital stability of solitary waves for Chen-Lee-Lin equation and Gerdjikov-Ivanov equation, respectively.     

HYERS-ULAM-RASSIAS STABILITY FOR A MULTIVALUED ITERATIVE EQUATION

Because multifunctions do not have so good properties as single-valued functions, only the existence of solutions of the polynomial-like iterative equation of order 2 is discussed for multi functions. This article gives conditions for its Hyers-Ulam-Rassias stability. As a consequence, the authors obtain its Hyers-Ulam stability and prove that the equation has a unique multivalued solution near an approximate multivalued solution.     

Stability in the almost everywhere sense: A linear transfer operator approach

The problem of almost everywhere stability of a nonlinear autonomous ordinary differential equation is studied using a linear transfer operator framework. The infinitesimal generator of a linear transfer operator (Perron-Frobenius) is used to provide stability conditions of an autonomous ordinary differential equation. It is shown that almost everywhere uniform stability of a nonlinear differential equation, is equivalent to the existence of a non-negative solution for a steady state advection type linear partial differential equation. We refer to this non-negative solution, verifying almost everywhere global stability, as Lyapunov density. A numerical method using finite element techniques is used for the computation of Lyapunov density.     

STABILITY THEOREM FOR A CLASS OF PERTURBED NONAUTONOMOUS NEUTRAL DIFFERENTIAL EQUATION WITH UNBOUNDED DELAY

In this paper, we consider a one-dimensional nonautonomous neutral differential equation. We obtain sufficient conditions under which the zero solution to this equation with unbounded delay and perturbation is uniformly asymptotically stable.     

Feedback stabilization of a marginally stable parabolic equation and a counterexample to a conjecture on this topic

The first part of this paper is concerned with the exponential stabilization of certain marginally stable equations by means of a feedback. If you think of the standard Neumann problem for the Laplacian as an example of a marginally stable equation, there is the conjecture that for feedbacks with restricted sign the feedback system is always exponentially stable. We disprove this conjecture in the second part of our paper     

关于扰动微分方程组零解部分变元的稳定性

本文讨论未被扰动运动关于部分变元的稳定性，一致稳定性和全局渐近稳定性，给出了一种判定，改进了文［１］中的相应定理。