POSITIVE SOLUTIONS OF NONLOCAL BOUNDARY VALUE PROBLEM FOR NONLINEAR RETARDED DIFFERENTIAL EQUATION

§1　IntroductionAt present,boundary value problems (BVPs) are widely investigated with variousmethods and techniques. BVPs with integral boundary conditions constitute a veryinteresting class of problems such as multipoint,three-point,four-point and nonlocalboundary value problems which are considered by many authors.And the existence ofpositive solutions for these problems becomes the subjectof many papers[1—6] .In a recentpaper[7] ,the authors have studied the existence of positive solut…     

ASYMPTOTIC BEHAVIOUR OF THE SOLUTIONS OF A CERTAIN FOURTH-ORDER DIFFERENTIAL EQUATION

The present paper establishes sufficient conditions for the uniformly bounded of any solution of (1.1) and which tend to zero as t → ∞.     

EXISTENCE OF GENERALIZED WEAKLY SOLUTIONS OF DIFFERENTIAL EQUATIONS IN PRODUCT SPACES

In this paper, by using Lyapunov function and weak noncompactness conditions, we give an existence theorem of generalized weakly solutions of Cauchy problem of differential equations in product spaces.     

强链回归集与强跟踪性

为了研究强跟踪性，本文给出了强链回归集的定义．证明了：若度量空间上的一个连续自映射有强跟踪性，则其强链回归集与极限集相同．     

ULTIMATE BOUNDEDNESS FOR A DIFFERENTIAL DELAY MODEL

This paper considers the scalar differential delay equation x(t) = -μx(t)-f(x(t-Τ(t)), t). By using the mapping method we obtain that the solutionswill be ultimately in some interval.     

On the solution of Falkner-Skan equations

New existence and uniqueness proofs are given for the solutions of the equations governing the self-similar compressible boundary layer (Falkner-Skan equations). The properties of the solutions are studied and some bounds on important quantities are concluded. The paper is restricted to favourable pressure gradients and to wall cooling.     

奇异微分系统的初值问题及其应用

利用依赖于解的奇异非线性时间变换，把奇异微分系统转换为非奇异的常微系统，建立了奇异微分系统初值问题解的(非)存在性和惟一性及多解的存在性．一阶和二阶奇异微分方程的初值问题的应用结果与Petio(2000)和Agarwal(1999)的结果相比，条件简单容易验证，且结论更详细。     

Periodic solutions of a second order forced sublinear differential equation with delay

In this paper, existence criteria are established for the existence of periodic solutions of a second order sublinear differential equation with delay and forcing function. Our method is based on careful a priori estimation and continuation theorems, and our sublinear condition is an improvement of the boundedness condition in some recent results.     

用无限阶Toeplitz矩阵求常系数微分方程的级数解

无限阶Toeplitz矩阵的属于0的特征向量可递推地求得,可表示常系数齐次微分方程的解.用它的逆可求得常系数非齐次微分方程的特解.