论实半单李代数的Cartan子代数的内共轭分类

<正> 1.实半单李代数的 Cartan 子代数的共轭分类问题好几位作者曾经讨论过.首先,B.Kostant 在1955年发表了他关于这一问题的讨论的摘要.他从 Cartan 子代数的“向量部分”的讨论出发,得出 Cartan 子代数的共轭分类的初步结果.随后,M.Sugiura 在Kostant 的讨论的基础上,也从“向量部分”的讨论出发得出 Cartan 子代数的共轭分类的完全结果.同年陈仲沪从 Cartan 子代数的“环面部分”的讨论出发,讨论了 Cartan 子代     

一类具有扩散的捕食模型的共存解

该文讨论了具有扩散的捕食模型.利用上下解方法和分支理论,得到了椭圆系统的共存解的存在性,并且讨论了共存解的稳定性.     

具有多合同的广义加权保费的信度估计(英文)

本文讨论了广义加权保费原理下的信度估计,并把结论推广到多合同模型.通过概率分布的变换,本文得到了多合同模型下广义加权保费的非齐次和齐次信度估计.并且讨论了这些估计的统计性质.最后,运用重抽样方法讨论了信度因子中未知结构参数的估计.数值模拟表明,非齐次信度估计能运用于保险实际.     

一类具滞后影响的捕食与被捕食者模型的探讨

1973年 May 讨论过模型(?)他主要从生态的角度进行了讨论.数学上的讨论集中在分析特征方程及平衡点的稳定性,并未严格证明非常数周期解的存在性.1957年 Wangersky 和 Cunuinghan 曾讨论过下面的模型:(?)他们的讨论比之前者更偏重于生态的讨论,很少涉及数学上的深入讨论.本文讨论下面的模型:     

任2n个元生成的子代数都是n步次理想的诣零Jordan代数

<正> 众所周知,幂零群的任一子群是n步次正规子群.反之如何呢?这正是[1]中的第22问题.对此,文章[2]进行了讨论.类似地,对于其它代数系统,[3]讨论了结合环,[4]讨论了Lie代数,[5]讨论了交错代数.本文讨论Jordan代数. 以下用J表示域F(特征任意)上的Jordan代数,表示由J的子集H生成的子代数.     

广义阿贝尔微分方程的周期解

本文讨论了广义阿贝尔微分方程.利用不动点定理,得到了方程存在两个非零周期解的充分条件.同时,我们还讨论了不存在非零周期解和存在唯一非零周期解的情况.     

自动微分的原理和方法

从计算一阶和二阶各种导数形式的角度,讨论了自动微分的基本原理和方法,给出了一阶和二阶各种微分模式最简单而最直观的表述形式,分别讨论了用不同微分模式计算不同导数形式的计算代价,讨论并给出了非线性问题求解中常用数值算法的计算代价.讨论了断点存储、正向积分和反向积分方法.     

鞅的自正则指数不等式

本文讨论了局部平方可积鞅,给出了Delyon不等式的推广形式. 这个结果对于建立鞅的自正则指数不等式有一定的意义. 本文还讨论了线性回归的一个应用.     

含估计参数的加权经验过程

在讨论(广义)非参数似然比拟合优度检验时,加权经验过程理论是一个非常重要的基础.但对含估计参数的加权经验过程理论,目前文献中很少讨论.对含估计参数的加权经验过程的上界型和积分型两种统计量的近似分布进行了讨论,给出了较一般的结果.所得结论叮以为进一步讨论复合零假设下(广义)非参似然比拟合优度检验提供理论基础.     

林木病虫害的动力学模型

本文讨论森林病虫害方程 ,建立了森林病虫害的一些常微分方程模型 ,并讨论了模型解的性质 .     

一个A（f）≠M（f）的紧致系统（X，f）

本文证明，存在紧致系统，其几乎周期点集闭包不等于其测度中心．藉此，我们否定地回答了两个未解决的问题．     

Construction of almost periodic solutions to one quasilinear system with two delays

In this paper we construct an almost periodic solution to a quasilinear system with constant and linear delays. We prove the asymptotic stability of this solution.     

PERIODIC SOLUTIONS AND ALMOST PERIODIC SOLUTIONS OF A NONAUTONOMOUS PREDATOR-PREY SYSTEM WITH STAGE-STRUCTURE AND DELAY

In this paper, by using the comparing theorem, Razumikhin-type theorem and V-function method, we consider a nonautonomous predator-prey system with stage-structure and time-delay. We get the sufficient conditions for the uniform persistence and the solutions global attractivity of this system. For a periodic system, we obtain the existence and uniqueness of a positive periodic solution of this system. For an almost periodic system, we prove the existence and the uniform asymptotic stability of the almost periodic solutions of this system.     

Exponential stability of pseudo almost periodic delayed Nicholson‐type system with patch structure

In this paper, we consider the existence and global exponential stability of positive pseudo almost periodic solutions for a delayed Nicholson‐type system with patch structure. With the aid of ergodic theory and differential inequality technique, we prove the existence and global exponential stability of positive pseudo almost periodic solutions for the addressed system, which generalize and improve some known results. Specially, an example and its numerical simulations are provided to manifest the effectiveness of theoretical results.     

Global dynamics behaviors for a nonautonomous Lotka–Volterra almost periodic dispersal system with delays

A nonautonomous Lotka–Volterra dispersal system with continuous delays and discrete delays is considered. By using a comparison theorem and delay differential equation basic theory, we obtain sufficient conditions for the permanence of the population in every patch. By constructing a suitable Lyapunov functional, we prove that the system is globally asymptotically stable under some appropriate conditions. Using almost periodic functional hull theory, we get sufficient conditions for the existence, uniqueness and globally asymptotical stability for an almost periodic solution. This implies that the population in every patch exhibits stable almost periodic fluctuation. Furthermore, the results show that the permanence and global stability of system, and the existence and uniqueness of a positive almost periodic solution, depend on the delay; then we call it “profitless”.     

Periodic solution and almost periodic solution for a nonautonomous Lotka-Volterra dispersal system with infinite delay

This paper studies a nonautonomous Lotka-Volterra dispersal systems with infinite time delay which models the diffusion of a single species into n patches by discrete dispersal. Our results show that the system is uniformly persistent under an appropriate condition. The sufficient condition for the global asymptotical stability of the system is also given. By using Mawhin continuation theorem of coincidence degree, we prove that the periodic system has at least one positive periodic solution, further, obtain the uniqueness and globally asymptotical stability for periodic system. By using functional hull theory and directly analyzing the right functional of almost periodic system, we show that the almost periodic system has a unique globally asymptotical stable positive almost periodic solution. We also show that the delays have very important effects on the dynamic behaviors of the system.     

Dynamic analysis of a non-autonomous ratio-dependent predator-prey model with additional food

In this paper, a non-autonomous ratio-dependent three species predator-prey system with additional food to top predator was proposed. The permanence of the model is obtained. Based on the continuation theorem, the sufficient conditions for the existence of a periodic solution are obtained. By using the method of Lyapunov function, we prove that the system exists a unique positive almost periodic solution under some certain conditions.     

Almost periodicity,finite automata mappings,and related effectiveness issues

We introduce a class of eventually almost periodic sequences where some suffix is almost periodic (i.e., uniformly recurrent). The class of generalized almost periodic sequences includes the class of eventually almost periodic sequences, and we prove this inclusion to be strict. We also prove that the class of eventually almost periodic sequences is closed under finite automata mappings and finite transductions. Moreover, we obtain an effective form of this result. In conclusion we consider some algorithmic questions related to the almost periodicity.     

PROPERLIES OF ALMOST PERIODIC SOLUTION FOR A KIND OF ECOLOGICAL SYSTEMSWITH TIME DELAY

AMSSubjectClassification34C27Thespatialelementinpopulationbiologyisimportanttounderstandthedynamicsofecologicalsystems.ThetheoreticalworksonthisproblemwerepioneeredbySkellamif]in1951andwerereviewedbyLevin[2]in1974.In12],Levinfirstestablishedthiskindofmode…     

Almost-periodic solutions to systems of differential equations with fast and slow time in the degenerate case

We consider a system of ordinary first-order differential equations. The right-hand sides of the system are proportional to a small parameter and depend almost periodically on fast time and periodically on slow time. With this system, we associate the system averaged over fast time. We assume that the averaged system has a structurally unstable periodic solution. We prove a theorem on the existence and stability of almost periodic solutions of the original system. Translated fromMatematicheskie Zametki, Vol. 63, No. 3, pp. 451–456, March, 1998.