On Solvability of Boundary Value Problems for Kinetic Operator-Differential Equations

We study solvability of boundary value problems for the so-called kinetic operator-differential equations of the form B(t)u _t ?L(t)u = f, where L(t) and B(t) are families of linear operators defined in a complex Hilbert space E. We do not assume that the operator B is invertible and that the spectrum of the pencil L ?λ B is included into one of the half-planes Re λ < a or Re λ > a \({(a\in {\mathbb{R}})}\) . Under certain conditions on the above operators, we prove several existence and uniqueness theorems and study smoothness questions in weighted Sobolev spaces for solutions.     

扰动周期边值问题的可解性

本文借助于Borsuk定理的拓扑度的同任性,建立了一类拓动周期边值问题解的存在性定理。     

Strong Solvability of Boundary Value Contact Problems

Strong solvability in Sobolev spaces is proved for a unilateral contact boundary value problem for a class of nonlinear discontinuous operators. The operator is assumed to be of Caratheodory type and to satisfy a suitable ellipticity condition. Only measurability with respect to the independent variable x is required. The main tool of the proof is an estimate for the second derivatives of the functions which satisfy the unilateral boundary conditions, in which it has been possible to prove that the constant is equal to 1.     

一类非线性泛函边值问题的可解性

本文考虑非线性泛函边值问题，利用Ｂｏｒｓｕｋ定理与Ｌｅｒａｙ－Ｓｃｈａｕｄｅｒ不动点定理，得到了上述边值问题的若干可解性结果。     

不连续三阶两点边值问题的可解性

证明了非线性三阶两点边值问题u′″（t）-q（u″（t））f（t，u（t）），u（O）=a，u（1）=b，u″（0）=c解的一个存在定理．在这个问题中，f（t，u）是一个Carathéodory函数而边界条件是非齐次的．我们的结论表明该问题能够有一个解，只要在R。的某个有界集合上q（υ）的“本性高度”与f（t，u）的“最大高度”积分的乘积是适当的．     

一类三阶两点边值问题的可解性

讨论了一类非线性项含一阶和二阶导数的三阶两点边值问题的可解性.在非线性项f满足线性增长的限制的条件下.通过构造适当的Banach空间并利用Leray-Schauder非线性抉择证明了一个存在定理.     

共振下椭圆偏微分方程边值问题的可解性:无标准Landesman-Lazer条件情形

本文研究如下共振下的椭圆偏微分方程边值问题的可解性：△u＋λku＋g（x，u）＝h（x）；u＝0，x∈Ω．提出了三类非标准的Landesman－Lazer条件，证明了上述问题弱解存在性的非常一般性的结果．最有意义的应用是关于λk＝λ1的情形，在此我们使用了几种易于验证的非标准的Landesman－Lazer条件（或拟Landesman－Lazer条件）．进一步，我们提出了新的符号条件从而全面推广了Figueiredo和倪维明（［1］）的一个主要结果．     

一类二阶拟线性边值问题的可解性

当非线性项奇异和无穷远处的极限增长函数存在时,考察了一类二阶拟线性边值问题.通过引入非线性项在有界集合上的高度函数,并且考察高度函数的积分,证明了一个解的存在定理.该定理表明当极限增长函数的积分具有适当值时此问题有一个解.     

Solvability of Elliptic Boundary Value Problems without Standard Landesman-Lazer Condition

Abstract In this paper we prove a very general result concerning solvability of the resonant problem: Δu + λ_κ u + g(x, u) = h (x); u = 0, x ∈∂Ω, which immediately gives three generalized Landesman-Lazer conditions. The most interesting application of the general result is concerned with the problem when λ_κ = λ₁, in which case we prove solvability results for it under conditions which are not the standard Landesman-Lazer condition or only partly enjoy it. Furthermore, we propose a new sign condition and give a comprehensive extension of a main result of Figueiredo and Ni.     

Solvability of Boundary Value Problems for Some Functional Differential Equations

This paper considers the following boundary value problems for functional differential equations: x' (t) = f(t, xt) (0相似文献   

Solvability of Boundary Value Problems for Operator-Differential Equations of Mixed Type

Siberian Mathematical Journal -     

On the Solvability of the Same Nonlinear Compound Boundary Valued Problems

In this paper, we may make tbe following: {|W(t)| = Φ(t), \qquad t ∈ L ⊂ ∂D Re[a(t) - i · b(t)]W(t) = ψ(t), t ∈ M = ∂D - L equal to searching for a positive solution of nonlinear singular integral equation. The solvability and discrete approximate solution of the singular integral equation have been studied.     

Solvability for Some Higher Order Multi-Point Boundary Value Problems at Resonance

In this paper, by using the Mawhin’s continuation theorem, we obtain an existence theorem for some higher order multi-point boundary value problems at resonance in the following form: $$\begin{array}{lll}x^{(n)}(t) = f(t,x(t),x'(t),\ldots,x^{(n-1)}(t))+e(t),\ t\in(0,1),\\x^{(i)}(0) = 0, i=0,1,\ldots,n-1,\ i\neq p, \\x^{(k)}(1) = \sum\limits_{j=1}^{m-2}{\beta_j}x^{(k)}(\eta_j),\end{array}$$ where ${f:[0,1]\times \mathbb{R}^n \to \mathbb{R}=(-\infty,+\infty)}$ is a continuous function, ${e(t)\in L^1[0,1], p, k\in\{0,1,\ldots,n-1\}}$ are fixed, m ≥ 3 for p ≤ k (m ≥ 4 for p > k), ${\beta_j \in \mathbb{R}, j=1,2,\ldots,m-2, 0 < \eta_1 < \eta_2 < \cdots < \eta_{m-2} <1 }$ . We give an example to demonstrate our results.     

一类多点边值问题的可解性

This paper deals with the existence of solutions for the problem
{（Фp（u′））′=f（t,u,u′）,t∈（0,1）,
u′（0）=0,u（1）=∑i=1^n-2aiu（ηi）,
where Фp（s）=｜s｜^p-2s,p〉1.0〈η1〈η2〈…〈ηn-2〈1,ai（i=1,2,…,n-2）are non-negative constants and ∑i=1^n-2ai=1.Some known results are improved under some sign and growth conditions. The proof is based on the Brouwer degree theory.     

Banach空间中高阶常微分方程初边值问题的可解性

利用基于度理论的不动点定理,该文给出了Ｂａｎａｃｈ空间中ｎ阶常微分方程的初、边值问题有解的某些充分条件,同时证明了一类最大最小解的存在性．推广了现有文献中的某些结果．