Periodic solutions of Abel differential equations

For a class of polynomial non-autonomous differential equations of degree n, we use phase plane analysis to show that each equation in this class has n periodic solutions. The result implies that certain rigid two-dimensional systems have at most one limit cycle which appears through multiple Hopf bifurcation.     

On the determination of the number of periodic (or closed) solutions of a scalar differential equation with convexity

It is well known that a scalar differential equation , where f(t,x) is continuous, T-periodic in t and weakly convex or concave in x has no, one or two T-periodic solutions or a connected band of T-periodic solutions. The last possibility can be excluded if f(t,x) is strictly convex or concave for some t in the period interval. In this paper we investigate how the actual number of T-periodic solutions for a given equation of this type in principle can be determined, if f(t,x) is also assumed to have a continuous derivative . It turns out that there are three cases. In each of these cases we indicate the monotonicity properties and the domain of values for the function P(ξ)=S(ξ)−ξ, where S(ξ) is the Poincaré successor function. From these informations the actual number of periodic solutions can be determined, since a zero of P(ξ) represents a periodic solution.     

Existence of nontrivial nonnegative periodic solutions for a class of doubly degenerate parabolic equation with nonlocal terms

In this paper, the authors establish the existence of nontrivial nonnegative periodic solutions for a class of doubly degenerate parabolic equation with nonlocal terms by using the theory of Leray-Schauder's degree.     

Two classes of piecewise-linear difference equations with eventual periodicity three

In this paper, we will study two classes of difference equations which are piecewise-linear and of similar forms. We will show that all nontrivial solutions of one equation are eventually periodic with prime period three. We will show this result for one case of the second equation.     

共振下n维Lienard型方程的2π周期解

本文在跨共振点条件下证明n维Lienard型方程存在2π周期解.     

带Carathodory函数的积分微分方程周期边值问题

本文研究带Caratheodory函数的非线性Volterra型积分微分方程周期边值问题．对于下解α与上解β的两种情形：或,解的存在性和建立极解的单调迭代法均被讨论．     

PERIODIC SOLUTION AND ASYMPTOTICITY OF ABEL EQUATION

Inarticles[1]and[2]theexistenceandstabilityofperiodicsolutionofAbelequation:werediscllsscd,wb')lteth'3coefficientsa(t),b(t),c(t)andd(t)areradalcollt,inuouslyp(3riodicfunctions.111thispal)erwenotonlystudythegeneralI\)rnlofeqllation(A),hiltalsodiscllssitssomespecialcases.FOT'example,as(l(l-)=0l,hcAbelequationbecomesfWeshallobtainsomeinterestingresultsfromit,suchdoubleperiodicsolution,etc.Equation(B)alsohassomeapplication,weknowthattheOdum(1971)*ThispaperissponsoredbyNationalScienceFundation…     

二维周期系数线性微分方程的特征指数

给出利用系数直接判定二维周期系数线性微分方程特征指数符号的若干结论．     

Interpolation on Sparse Grids and Tensor Products of Nikol'skij–Besov Spaces

We investigate the order of convergence of periodic interpolation on sparse grids (blending interpolation) in the framework of tensor products of Nikol'skij–Besov spaces. To this end, we make use of the uniformity of the considered tensor norms and provide a unified approach to error estimates for the interpolation of univariate periodic functions from Nikol'skij–Besov spaces.     

REAL-VALUED PERIODIC WAVELETS: CONSTRUCTION AND RELATION WITH FOURIER SERIES

1.IntroductionWaveletshaverecentlyreceivedagreatdealofattentioninsuchareasassignalprocessingandimageprocessing([12],[8]).Variousmethodstoconstructwaveletshavebeengiven([14],[13],[9],[7]).Itiswellknownthatinmathematicsandmathematicphysicsmanyperiodicp...