This paper is concerned with the following n-th ordinary differential equation:{u～(n)(t)=f(t,u(t),u～(1)(t),···,u～(n-1) (t)),for t∈(0,1),u～(i) (0)=0,0 ≤i≤n3,au～(n-2)(0)du～(n-1)(0)=0,cu～(n-2)(1)...This paper is concerned with the following n-th ordinary differential equation:{u～(n)(t)=f(t,u(t),u～(1)(t),···,u～(n-1) (t)),for t∈(0,1),u～(i) (0)=0,0 ≤i≤n3,au～(n-2)(0)du～(n-1)(0)=0,cu～(n-2)(1)+du～(n-1)(1)=0,where a,c ∈ R,,≥,such that a～2 + b～2 >0 and c～2+d～2>0,n ≥ 2,f:[0,1] × R → R is a continuous function.Assume that f satisfies one-sided Nagumo condition,the existence theorems of solutions of the boundary value problem for the n-th-order nonlinear differential equations above are established by using Leray-Schauder degree theory,lower and upper solutions,a priori estimate technique.展开更多
This paper deals with a four-point boundary value problem [φ(u')]' = f(t, u, u'),a < t < b with u(a) - u(ao) = A, u(b) - u(bo) = B, where a < a0 <b0 < b.
This paper is concerned with the existence of periodic solutions for a nonlinear system of ordinary differential equations.We obtain a Nagumo-type a priori bound for the periodic solutions and then by using this a pri...This paper is concerned with the existence of periodic solutions for a nonlinear system of ordinary differential equations.We obtain a Nagumo-type a priori bound for the periodic solutions and then by using this a priori bound we prove the existence of at least one T-periodic solution under some general conditions展开更多
The author studies the boundary value problems for systems of nonlinear second order differential dmerence equstions and adopts a new-type Nagumo conditinn, in which the controlfunction is a vector-Valued function of ...The author studies the boundary value problems for systems of nonlinear second order differential dmerence equstions and adopts a new-type Nagumo conditinn, in which the controlfunction is a vector-Valued function of several variables and which can guarsntee simultaneously and easily finding a priori bounds of eaCh component of the deriVatives of the solutions.Under this new-type Nagumo condition the existence results of solution are proved by meansof differential inopality technique.展开更多
This paper is concerned with a singular second-order nonlinear boundary value problem with a time depending on derivative operator and posed on the positive half-line. The nonlinearity is derivative-dependent, which h...This paper is concerned with a singular second-order nonlinear boundary value problem with a time depending on derivative operator and posed on the positive half-line. The nonlinearity is derivative-dependent, which has singularities at t=0 and/or x=0, and may change sign. The method of the upper and lower solutions on unbounded domains combined with the topological degree theory are employed to prove the existence and multiplicity of solutions.展开更多
文摘This paper is concerned with the following n-th ordinary differential equation:{u～(n)(t)=f(t,u(t),u～(1)(t),···,u～(n-1) (t)),for t∈(0,1),u～(i) (0)=0,0 ≤i≤n3,au～(n-2)(0)du～(n-1)(0)=0,cu～(n-2)(1)+du～(n-1)(1)=0,where a,c ∈ R,,≥,such that a～2 + b～2 >0 and c～2+d～2>0,n ≥ 2,f:[0,1] × R → R is a continuous function.Assume that f satisfies one-sided Nagumo condition,the existence theorems of solutions of the boundary value problem for the n-th-order nonlinear differential equations above are established by using Leray-Schauder degree theory,lower and upper solutions,a priori estimate technique.
文摘This paper deals with a four-point boundary value problem [φ(u')]' = f(t, u, u'),a < t < b with u(a) - u(ao) = A, u(b) - u(bo) = B, where a < a0 <b0 < b.
基金Research supported by the NNSF of China and the RFDP of China.
文摘This paper is concerned with the existence of periodic solutions for a nonlinear system of ordinary differential equations.We obtain a Nagumo-type a priori bound for the periodic solutions and then by using this a priori bound we prove the existence of at least one T-periodic solution under some general conditions
文摘The author studies the boundary value problems for systems of nonlinear second order differential dmerence equstions and adopts a new-type Nagumo conditinn, in which the controlfunction is a vector-Valued function of several variables and which can guarsntee simultaneously and easily finding a priori bounds of eaCh component of the deriVatives of the solutions.Under this new-type Nagumo condition the existence results of solution are proved by meansof differential inopality technique.
文摘This paper is concerned with a singular second-order nonlinear boundary value problem with a time depending on derivative operator and posed on the positive half-line. The nonlinearity is derivative-dependent, which has singularities at t=0 and/or x=0, and may change sign. The method of the upper and lower solutions on unbounded domains combined with the topological degree theory are employed to prove the existence and multiplicity of solutions.
