具有分布偏差变元的二阶中立型方程的振动准则(英文)

利用Riccati变换及积分平均技巧,建立一类具有非线性中立项及分布偏差变元的二阶中立型方程的振动准则,我们的结果推广并改进了一些已有的结果.     

一类半线性椭圆型方程爆炸解的存在性与渐近行为

设Ω是Ｒ＾Ｎ（Ｎ≥２）中的Ｃ＾２有界区域,对非线性项带有适当的梯度与无界系数ｋ（ｘ）,首先应用非线性变换将爆炸解问题,转化成等价的带奇异项的Ｄｉｒｉｃｈｌｅｔ问题,应用极大值原理得到爆炸解问题的最小爆炸速度。随后,应用摄动方法,结合上下解方法与椭圆型方程的估计理论得到了爆炸解的存在性。     

Multi-separation, centrifugality and centripetality imply chaos

Let be an interval. need not be compact or bounded. Let be a continuous map, and be a trajectory of with or . Then there is a point such that . A point is called a centripetal point of relative to if or , and is centrifugal if or . In this paper we prove that if there exist centripetal points of in , then has periodic points of some odd () period . In addition, we also prove that if ) is multi-separated by Fix(), or there exists a centrifugal point of in , then is turbulent and hence has periodic points of all periods.

     

一类具阻尼非线性波动方程的Cauchy问题

本文研究一类具阻尼非线性波动方程Cauchy问题整体广义解和整体古典解的存在唯一性,并用凸性方法给出解爆破的充分条件.     

离心力场作用下多孔介质中强制对流换热的研究

对离心流化床中空气通过多孔物料层的强制对流换热进行了理论和实验研究。获得了气流和物料间强制对流换热的准则关联式。研究结果表明,在气流速度和温度梯度方向一致的条件下,强制对流换热比通常的边界层强制对流换热有所强化,其换热的准则关联式具有 Nu=CRePr的线性形式。从而验证了改变气流方向和热流密度矢量之间夹角可以强化换热的这一强化传热新原理。     

A new chaotic system without linear term and its impulsive synchronization

In this paper, a new chaotic system without linear term is presented by ordinary differential equations, and some basic dynamical properties are studied. Moreover, the impulsive synchronization problem of the new chaotic systems is investigated by using uncertain impulsive control matrix. Using the impulsive theory, sufficient conditions are derived for the synchronization of new chaotic systems. Numerical simulation example is provided to verify the effectiveness of the proposed approach.     

一种捕捉多向刚性爆轰波的激波定位随机投影方法

提出一种激波定位随机投影方法,利用当地随机投影,引入激波指示器并提出恰当的判定当地投影区域的规则,使爆轰波多向推进的问题得以解决。数值实验表明,激波定位随机投影方法不仅适用于爆轰波的多向推进,还能高效求解刚性反应方程,易于推广到三维情况。     

On the Length of Scales of Computability Potentials for n-Element Algebras

We find the length of scales of computability potentials for n-element algebras. As a consequence, we find the length of the filter generated by the clone of a discriminant function in the lattice of clones of functions on an n-element set.     

带非线性源项的变分不等式的区域分解法及其收敛速度分析

本文考虑一类带非线性源项的变化不等式。针对其有限元离散问题,我们构造了乘性与加性Ｓｃｈｗａｒｚ算法,其产生的上解序列或下解序列不仅单调收敛于有限元解,而且具有限元网格ｈ无关的收敛率．