基于微分同胚的非线性系统解耦线性化

利用现代微分几何方法研究了非线性系统，通过构造适当的微分同胚，给出了非线性系统解耦线性化的充分必要条件。最后，用数值例子说明了本文所得的结论。     

一类广义浅水波KdV方程的可积性研究

该文应用双Bell多项式,系统研究了一类广义浅水波KdV方程的可积性.先构造出双线性表达式、B?klund变换,再通过B?klund变换线性化得到孤子解与Lax对.最后通过级数展开式代入得到无穷守恒律,从而证明此方程具有可积性.     

时变仿射非线性系统的动态补偿线性化

用微分几何方法讨论了时变仿射非线性系统的动态补偿线性化问题，给出了系统动态的反馈线性化的条件，它是状态反馈线性化的推广。     

基于Bell多项式的一类(3+1)维变系数广义浅水波方程的可积性研究

本文基于Bell多项式研究了一类(3+1)维变系数广义浅水波方程的可积性问题.首先,引入变量变换,借助Bell多项式与Hirota双线性算子之间的关系,导出方程的Hirota双线性形式,求出方程的N-孤子解,并对单孤子、双孤子和三孤子在不同情形下的传播进行图像模拟;其次,基于双线性方程,结合Bell多项式获得方程的双线性B?cklund变换;然后,通过Hopf-Cole变换,将双线性Backlund变换线性化,求出方程的Lax对;最后,利用级数展开法得到方程的无穷守恒律.从而证明该方程具有可积性.     

垂直裂缝气藏中凝析油气试井模型及应用

凝析气井经过压裂产生垂直裂缝,流体在地层与裂缝中往往形成双线性流.根据凝析气形成的双线性流渗流特点,通过凝析油气不稳定渗流的基本微分方程,经过线性化处理,考虑裂缝传导能力和表皮效应,应用拉普拉斯变换,建立了垂直裂缝气藏中凝析油气渗流的双线性流的新模型,求出了模型的解.并绘出了凝析气藏试井理论曲线,通过试井测试资料解释,可计算凝析气井的地层渗透率,气藏压力,裂缝传导能力和裂缝表皮系数等相应的地层参数,可为气藏开发提供动态参数和理论依据.     

线性奇异系统的解耦问题

本文讨论在状态反馈下的线性奇异系统的解耦问题，利用奇异系统的受限等价变换，给出了输出，输入维数相同的方线性奇异系统解耦问题有解的充分必要条件。     

Markov切换随机双线性系统依概率渐进稳定性

本文研究随机双线性系统大范围渐进稳定性。利用数学期望不等式给出了随机双线性系统渐进稳定的新标准。设计了一种非线性状态反馈控制器,利用类Riccati不等式推出了Markov切换随机双线性系统大范围依概率渐进稳定的充分条件。数值算例表明本文提出的方法是可行的。     

一类时变仿射非线性系统的动态状态反馈线性化的条件

本文用微分几何方法讨论了一类时变仿射非线性系统（即ｎ＝ｍ＋１）的动态状态反馈线性化与系统的线性近似的关系，得出了系统可动态状态反馈线性化的条件。     

基于谱变换的奇异二阶系统解耦研究

针对奇异二阶系统的解耦问题,提出了一种基于谱变换的解耦方法.首先分析了质量矩阵非奇异的解耦条件,提出一种非奇异二阶同谱对角系统的构造解耦方法,然后引入谱变换将首系数转换为非奇异的,利用非奇异的构造方法来构造同谱对角系统,最后对解耦系统进行还原,从而实现奇异二阶系统的解耦.数值试验证明该方法确实有效.     

用精确线性化控制Lorenz混沌

本文采用状态空间精确线性化方法研究Ｒａｙｌｅｉｇｈ数可控的Ｌｏｒｅｎｚ系统中混沌的控制问题·在证明系统可以精确线性化的基础上，借助非线性反馈构造出变换关系使原系统转化为线性可控系统而实现控制，并给出了控制算例     

Consistent systems and pole assignment: I

We study the consistency property of a linear time-invariant control system with incomplete feedback and of a bilinear time-invariant control system in connection with the pole assignment problem. We show that consistency is a sufficient and, in some cases, necessary condition for the arbitrary pole assignability of systems with coefficients of a special form.     

Invariant bilinear forms on real irreducible representations of real semisimple lie algebras *

In this note, we give a necessary and sufficient condition for a real irreducible representation of a real simple Lie algebra to admit an invariant bilinear form. We also determine when the invariant bilinear form is symmetric or skew-symmetric.     

GENERALIZED RANK CONDITIONS FOR SYSTEMS IN A CATEGORY

ABSTRACT

A generalized rank condition is used to deduce necessary and sufficient conditions for the reachability and observability of a system in a category. A duality principle between reachability and observability is established. These results generalize those known previously for bilinear and linear systems over rings.     

Consistent systems and pole assignment: II

We obtain sufficient conditions for the consistency of a bilinear time-invariant control system. For systems with coefficients of special form, we prove the equivalence of the consistency of the bilinear system and the arbitrary pole assignability.     

The uniform asymptotic stability of certain neutral differential-difference equations

In this paper we give a necessary and sufficient condition for a general class of neutral differential-difference equations to be exponentially stable. This condition is expressed in terms of certain bilinear functionals which are the equivalent of quadratic Liapunov functions for finite-dimensional systems.     

Comments on the feedback stabilization for bilinear control systems

Necessary and sufficient condition are given for state feedback stabilization of distributed control bilinear systems. The results are based on the theory of linear and nonlinear contraction semigroups.     

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。     

对称自对偶李代数的一些性质

给出了一类带有非退化对称不变双线性型及对称自对偶李代数的分解唯一性的一个充分条件,并讨论此类李代数的特殊性质.     

Leibniz algebras with pseudo-Riemannian bilinear forms

M. Bordemann has studied non-associative algebras with nondegenerate associative bilinear forms. In this paper, we focus on pseudo-Riemannian bilinear forms and study pseudo-Riemannian Leibniz algebras, i.e., Leibniz algebras with pseudo-Riemannian non-degenerate symmetric bilinear forms. We give the notion and some properties of T*-extensions of Leibniz algebras. In addition, we introduce the definition of equivalence and isometrical equivalence for two T*-extensions of a Leibniz algebra, and give a sufficient and necessary condition for the equivalence and isometrical equivalence.     

Asymptotical Stability in Probability for Stochastic Bilinear Systems with Markovian Switching

This paper deals with asymptotical stability in probability in the large for stochastic bilinear systems. Some new criteria for asymptotical stability of such systems have been established in the inequality of mathematic expectation. A sufficient condition for bilinear stochastic jump systems to be asymptotically stable in probability in the large in Markovian switching laws is derived in a couple of Riccati-like inequalities by introducing a nonlinear state feedback controller. An illustrative example shows the effectiveness of the method.