共查询到20条相似文献,搜索用时 15 毫秒
1.
Guochun Wen 《分析论及其应用》2005,21(2):118-131
The present paper deals with the mixed boundary value problem for elliptic equations with degenerate rank 0. We first give the formulation of the problem and estimates of solutions of the problem, and then prove the existence of solutions of the above problem for elliptic equations by the above estimates and the method of parameter extension. We use the complex method, namely first discuss the corresponding problem for degenerate elliptic complex equations of first order, afterwards discuss the above problem for degenerate elliptic equations of second order. 相似文献
2.
《复变函数与椭圆型方程》2012,57(4):257-270
In [], the authors discussed the Tricomi problem of second order mixed equations with nonsmooth degenerate line, but they only consider some special mixed equations. In [], the author discussed the uniqueness of solutions of the Tricomi problem for some second order mixed equations with nonsmooth degenerate line. The present article deals with oblique derivative problems for general second order mixed equations with nonsmooth parabolic degenerate line, and prove the uniqueness of solutions of the problems. We first give the formulation of the problems for the equations, and then prove the uniqueness of solutions for the above problems. 相似文献
3.
This article studies positive solutions of Robin problem for semi-linear second order ordinary differential equations. Nondegeneracy and uniqueness results are proven for homogeneous differential equations. Necessary and sufficient conditions for the existence of one or two positive solutions for inhomogeneous differential equations or differential equations with concave-convex nonlinearities are obtained by making use of the nondegeneracy and uniqueness results for positive solutions of homogeneous differential equations. 相似文献
4.
闻国椿 《数学物理学报(B辑英文版)》2007,27(3):663-672
The present article deals with some boundary value problems for nonlinear elliptic equations with degenerate rank 0 including the oblique derivative problem.Firstly the formulation and estimates of solutions of the oblique derivative problem are given, and then by the above estimates and the method of parameter extension,the existence of solutions of the above problem is proved.In this article,the complex analytic method is used,namely the corresponding problem for degenerate elliptic complex equations of first order is firstly discussed,afterwards the above problem for the degenerate elliptic equations of second order is solved. 相似文献
5.
Hyung-Chun Lee Byeong Chun Shin 《Journal of Mathematical Analysis and Applications》2002,273(2):457-479
The long-time behavior of solutions for an optimal distributed control problem associated with the Boussinesq equations is studied. First, a quasi-optimal solution for the Boussinesq equations is constructed; this quasi-optimal solution possesses the decay (in time) properties. Then, some preliminary estimates for the long-time behavior of all solutions of the Boussinesq equations are derived. Next, the existence of a solution for the optimal control problem is proved. Finally, the long-time decay properties for the optimal solutions is established. 相似文献
6.
利用辅助方程与函数变换相结合的方法,构造了Degasperis-Procesi(D-P)方程的无穷序列类孤子新解.首先,通过两种函数变换,把D-P方程化为常微分方程组.然后,利用常微分方程组的首次积分,把D-P方程的求解问题化为几种常微分方程的求解问题.最后,利用几种常微分方程的Bcklund变换等相关结论,构造了D-P方程的无穷序列类孤子新解.这里包括由Riemannθ函数、Jacobi椭圆函数、双曲函数、三角函数和有理函数组成的无穷序列光滑孤立子解、尖峰孤立子解和紧孤立子解. 相似文献
7.
J. Baris 《Journal of Mathematical Analysis and Applications》2008,341(2):1155-1162
We investigate the existence problem for blow-up solutions of cubic differential systems. We find sets of initial values of the blow-up solutions. We also discuss a method of finding upper estimates for the blow-up time of these solutions. Our approach can be applied to systems of partial differential equations. We apply this approach to the Cauchy-Dirichlet problem for systems of semilinear heat equations with cubic nonlinearities. 相似文献
8.
9.
Many authors have discussed the Tricomi problem for some second order equations of mixed type, which has important applications in gas dynamics. In particular, Bers proposed the Tricomi problem for Chaplygin equations in multiply connected domains [L. Bers, Mathematical Aspects of Subsonic and Transonic Gas Dynamics, Wiley, New York, 1958]. And Rassias proposed the exterior Tricomi problem for mixed equations in a doubly connected domain and proved the uniqueness of solutions for the problem [J.M. Rassias, Lecture Notes on Mixed Type Partial Differential Equations, World Scientific, Singapore, 1990]. In the present paper, we discuss the general Tricomi-Rassias problem for generalized Chaplygin equations. This is one general oblique derivative problem that includes the exterior Tricomi problem as a special case. We first give the representation of solutions of the general Tricomi-Rassias problem, and then prove the uniqueness and existence of solutions for the problem by a new method. In this paper, we shall also discuss another general oblique derivative problem for generalized Chaplygin equations. 相似文献
10.
We consider the problem on periodic solutions for linear systems of functionaldifferential equations of neutral type with
periodic coefficients and periodic deviations of the argument. By reduction to associated functional equations, we derive
necessary and sufficient conditions under which the problem on periodic solutions for such a system is Fredholm or semi-Fredholm. 相似文献
11.
考 虑具有未 知源项的 某些非 线性伪 抛物 型方程 的反演 问题. 首先 将伪抛 物型 方程初 边值问 题化为非线 性发展方 程 Couch y 问题,然 后,利用半 群理论,论 证发展 方程反问 题解的存 在唯一 性,最后, 利用不 动点方法得到 伪抛物型方程反 问题的可解性 相似文献
12.
§1. ConditionsforGeneralEllipticComplexEquationsofFourthOrder LetDbeaboundeddomain,weconsiderthegeneralellipticcomplexequationoffourthorderinthefollowingformwz2z2=F(z,w,wz,wz,…,wz3,wz4,wz3z,wz3z,wz4)+G(z,w,wz,wz,…,wz3),F=∑j+k=4(j,k)≠(2,2)Qj… 相似文献
13.
Guo Chun Wen 《数学学报(英文版)》2008,24(11):1759-1774
The present paper deals with Tricomi and Frankl problems for generalized Chaplygin equations in multiply connected domains. We first give the representation of solutions of the Tricomi problem for the equations, and then prove the uniqueness and existence of solutions for the problem by a new method, i.e. the complex functions in the elliptic domain and the hyperbolic complex functions in hyperbolic domain are used. Finally we discuss the Frankl problem for generalized Chaplygin equations in multiply connected domains. 相似文献
14.
In this article, we first give the representation of solutions for the oblique derivative problem of mixed (Lavrentév-Bitsadze) equations in two connected domains, afterwards prove the uniqueness of solutions of the above problem. Moreover, we prove the solvability of oblique derivative problem for quasilinear mixed (Lavrentév-Bitsadze) equations of second order, and obtain a priori estimates of solutions of the above problem. The above problem is an open problem proposed by Rassias. 相似文献
15.
Anar T. Assanova Narkesh B. Iskakova Nurgul T. Orumbayeva 《Mathematical Methods in the Applied Sciences》2020,43(2):881-902
A periodic problem for the system of hyperbolic equations with finite time delay is investigated. The investigated problem is reduced to an equivalent problem, consisting the family of periodic problems for a system of ordinary differential equations with finite delay and integral equations using the method of a new functions introduction. Relationship of periodic problem for the system of hyperbolic equations with finite time delay and the family of periodic problems for the system of ordinary differential equations with finite delay is established. Algorithms for finding approximate solutions of the equivalent problem are constructed, and their convergence is proved. Criteria of well-posedness of periodic problem for the system of hyperbolic equations with finite time delay are obtained. 相似文献
16.
Andrzej Rozkosz 《Journal of Theoretical Probability》2013,26(4):1061-1083
We consider the Cauchy problem for systems of viscous conservation laws. We obtain three different but related stochastic representations of weak solutions of the problem: in terms of solutions to systems of usual backward stochastic differential equations, in terms of solutions to some stochastic backward systems, and in terms of solutions to some forward-backward stochastic differential equations. 相似文献
17.
Emil Minchev 《Southeast Asian Bulletin of Mathematics》2002,25(4):681-704
The paper deals with the asymptotic behaviour and global existence of solutions for some classes of nonlinear parabolic equations in regard to the monotone properties of the nonlinear term. The asymptotic behaviour of the solutions of initial-boundary value problem for nonlinear parabolic equations is studied via the method of differential inequalities in order to obtain oscillation criterion for the solutions. Existence of extremal solutions of semilinear elliptic and parabolic equations is investigated via monotone iterative methods. The extremal solutions are obtained via monotone iterates. 相似文献
18.
G. V. Demidenko V. A. Likhoshvai T. V. Kotova Yu. E. Khropova 《Siberian Mathematical Journal》2006,47(1):45-54
We establish a connection between solutions to a broad class of large systems of ordinary differential equations and solutions to retarded differential equations. We prove that solving the Cauchy problem for systems of ordinary differential equations reduces to solving the initial value problem for a retarded differential equation as the number of equations increases unboundedly. In particular, the class of systems under consideration contains a system of differential equations which arises in modeling of multiphase synthesis. 相似文献
19.
Tomasz Klimsiak 《Potential Analysis》2012,36(2):373-404
We prove that under natural assumptions on the data strong solutions in Sobolev spaces of semilinear parabolic equations in
divergence form involving measure on the right-hand side may be represented by solutions of some generalized backward stochastic
differential equations. As an application we provide stochastic representation of strong solutions of the obstacle problem
by means of solutions of some reflected backward stochastic differential equations. To prove the latter result we use a stochastic
homographic approximation for solutions of the reflected backward equation. The approximation may be viewed as a stochastic
analogue of the homographic approximation for solutions to the obstacle problem. 相似文献
20.
Michal Fec?kan JinRong Wang 《Communications in Nonlinear Science & Numerical Simulation》2012,17(7):3050-3060
This paper is motivated from some recent papers treating the problem of the existence of a solution for impulsive differential equations with fractional derivative. We firstly show that the formula of solutions in cited papers are incorrect. Secondly, we reconsider a class of impulsive fractional differential equations and introduce a correct formula of solutions for a impulsive Cauchy problem with Caputo fractional derivative. Further, some sufficient conditions for existence of the solutions are established by applying fixed point methods. Some examples are given to illustrate the results. 相似文献