自全国各地100多位理事Road Machinery Branch of China Highway and Transportation Society He

In this paper, a three dimensional ratio-dependent chemostat model with periodically pulsed input is considered. By using the discrete dynamical system determined by the stroboscopic map and Floquet theorem, an exact periodic solution with positive concentrations of substrate and predator in the absence of prey is obtained. When β is less than some critical value the boundary periodic solution (xs(t), 0, zs(t)) is locally stable, and when β is larger than the critical value there are periodic oscillations in substrate, prey and predator. Increasing the impulsive period τ, the system undergoes a series of period-doubling bifurcation leading to chaos, which implies that the dynamical behaviors of the periodically pulsed ratio-dependent predator-prey ecosystem are very complex.     

THE HAMILTONIAN SYSTEM AND COMPLETENESS OF SYMPLECTIC ORTHOGONAL SYSTEM

I.IntroductionThemethodofseparationofvariablesisimportanttosolvethesoluti0n0fprobIem0fmathematicalphysics,butmanyproblen1sofmathematicalphysicscannotseparatet'ariab1es,thereforeitrestrictstheranget0appIicatemethodofseparationofvariable.Inthepaperlll,Zhong…     

Stirling渐进公式的一个新的构造证明

本文用简易的分析工具，对ｎ！给出了一个精确等式，从而导出Ｓｔｉｒｌｉｎｇ渐近公式（２）的一个新的简短证明.     

样条的机械化求解

本文在逐次分解法的基础上，给出一种样条机械化求解方法．该方法对多项式样条，有理样条乃至更一般样条的研究都是十分有效的．它适用于三角剖分，矩形剖分乃至更一般的代数曲线剖分     

两个涉及第二类Stirling数的求和规则

本文利用第二类Ｓｔｉｒｌｉｎｇ数给出了两个求和规则，从而重新得到了一些古典组合恒等式的统一证明，并由此给出了一些级数求和的渐近估计。     

关于广义分数次积分的合成

Compositions of generalized fractional integral operators involving Gauss hy-pergeometric function with power weights are studied. Composition formulas for such integrals which are the operators of the same type are obtained. In parti-cular, compositions of two identical operators are given.     

关于一类复值大数的积分（英）

Here presented are two limit theorems for a kind of integrals involvingcomplex-valued functions of large numbers. The form of integrals may be regardedas a natural generalization of those integrals occured in the probability limit theoremsof Chung and Erds. Our main result is Theorem 2 whose Proof rests upon some knownresults of [1] and makes an extentive use of Bonnet's second mean value theorem andrelated analytic techniques.     

关于重积分换元公式证明的一个评注

本文指出了现行数学分析教本中有关重积分换元公式证明所普遍忽视的一个漏洞，同时给出了该公式的一个新的初等证明．     

Sasakian空间型的C-全实伪脐子流形

本文讨论了Ｓａｓａｋｉａｎ空间型的Ｃ-全实伪脐子流形，给出关于第二基本形式长度的一个Ｐｉｎｃｈｉｎｇ定理．     

关于含有Stirling公式的双边不等式(英)

本文证明了有关n！的一个便于应用的双边不等式，它对一切自然数都成立，且当n变大时，上界不等式能给出误差界为O（n^－3）的Stirling渐近公式，从一定意义上说，文中的上界不等式具有最优形式，因为其中的常数0．5已作了最佳选择．文末还给出了关于Catalan数的一个双边不等式．