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LOWER BOUNDS OF DIRICHLET EIGENVALUES FOR A CLASS OF FINITELY DEGENERATE GRUSHIN TYPE ELLIPTIC OPERATORS 被引量:2
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作者 陈化 陈洪葛 +1 位作者 段忆芮 胡鑫 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1653-1664,共12页
Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmande... Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmander's condition, then the vectorfield is finitely degenerate and the sum of square operator △X =m∑j=1 X2 j is a finitely de-generate elliptic operator. In this paper, we shall study the sharp estimate of the Dirichlet eigenvalue for a class of general Grushin type degenerate elliptic operators △x on Ω. 展开更多
关键词 Dirichlet eigenvalues finitely degenerate elliptic operators HSrmander's con-dition sub-elliptic estimate Grushin type operator
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THE FIRST BOUNDARY VALUE PROBLEM FOR A CLASS OF QUASILINEAR DEGENERATE ELLIPTIC EQUATIONS 被引量:2
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作者 赵俊宁 曾小明 《Acta Mathematica Scientia》 SCIE CSCD 2005年第4期577-586,共10页
In this paper, the first boundary value problem for quasilinear equation of the form △A(u,x)+∑i=1^m δb^i(u,x)/δxi+c(u,x)=0,Au(u,x) ≥0is studied. By using the compensated compactness theory, some results... In this paper, the first boundary value problem for quasilinear equation of the form △A(u,x)+∑i=1^m δb^i(u,x)/δxi+c(u,x)=0,Au(u,x) ≥0is studied. By using the compensated compactness theory, some results on the existence of weak solution are established. In addition, under certain condition the uniqueness of solution is proved. 展开更多
关键词 Dirichlet problem degenerate elliptic equation existence of solutions
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HLDER ESTIMATES FOR A CLASS OF DEGENERATE ELLIPTIC EQUATIONS 被引量:1
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作者 宋巧珍 王立河 李东升 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1202-1218,共17页
In this paper we study the regularity theory of the solutions of a class of degenerate elliptic equations in divergence form. By introducing a proper distance and applying the compactness method we establish the HSlde... In this paper we study the regularity theory of the solutions of a class of degenerate elliptic equations in divergence form. By introducing a proper distance and applying the compactness method we establish the HSlder type estimates for the weak solutions. 展开更多
关键词 degenerate elliptic equations HSlder estimates compactness method
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INFINITELY MANY SOLUTIONS FOR A CLASS OF DEGENERATE ELLIPTIC EQUATIONS 被引量:1
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作者 李珂 魏红军 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1899-1910,共12页
Let X = (X1, ···, Xm) be an infinitely degenerate system of vector fields. The aim of this paper is to study the existence of infinitely many solutions for the sum of operators X =sum ( ) form j=1 t... Let X = (X1, ···, Xm) be an infinitely degenerate system of vector fields. The aim of this paper is to study the existence of infinitely many solutions for the sum of operators X =sum ( ) form j=1 to m Xj Xj. 展开更多
关键词 degenerate elliptic equations logarithmic Sobolev inequality
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STRONG COMPACTNESS OF APPROXIMATE SOLUTIONS TO DEGENERATE ELLIPTIC-HYPERBOLIC EQUATIONS WITH DISCONTINUOUS FLUX FUNCTION 被引量:1
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作者 Helge Holden Kenneth H. Karlsen +1 位作者 Darko Mitrovic Evgueni Yu. Panov 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1573-1612,共40页
Under a non-degeneracy condition on the nonlinearities we show that sequences of approximate entropy solutions of mixed elliptic-hyperbolic equations are strongly precompact in the general case of a Caratheodory flux ... Under a non-degeneracy condition on the nonlinearities we show that sequences of approximate entropy solutions of mixed elliptic-hyperbolic equations are strongly precompact in the general case of a Caratheodory flux vector. The proofs are based on deriving localization principles for H-measures associated to sequences of measurevalued functions. This main result implies existence of solutions to degenerate parabolic convection-diffusion equations with discontinuous flux. Moreover, it provides a framework in which one can prove convergence of various types of approximate solutions, such as those generated by the vanishing viscosity method and numerical schemes. 展开更多
关键词 degenerate hyperbolic-elliptic equation degenerate convection-diffusion equation conservation law discontinuous flux approximate solutions COMPACTNESS
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TWO PROBLEMS OF HERMITE ELLIPTIC EQUATIONS
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作者 黄飞敏 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期409-414,共6页
In this article, the author investigates some Hermite elliptic equations in a modified Sobolev space introduced by X. Ding [2]. First, the author shows the existence of a ground state solution of semilinear Hermite el... In this article, the author investigates some Hermite elliptic equations in a modified Sobolev space introduced by X. Ding [2]. First, the author shows the existence of a ground state solution of semilinear Hermite elliptic equation. Second, the author studies the eigenvalue problem of linear Hermite elliptic equation in a bounded or unbounded domain. 展开更多
关键词 Hermite elliptic equation modified Sobolev space eigenvalue problem
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THE MIXED PROBLEM FOR DEGENERATE ELLIPTIC EQUATIONS OF SECOND ORDER
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作者 Guochun Wen 《Analysis in Theory and Applications》 2005年第2期118-131,共14页
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 e... 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 展开更多
关键词 mixed problem elliptic equations degenerate rank 0
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A NOTE ON REGULARITY AND EXISTENCE OF SOLUTIONS FOR A CLASS OF NON-UNIFORMLY DEGENERATE ELLIPTIC EQUATIONS
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作者 LI JUNJIE(Dept.of Math.,Zhejiang University,Hangzhou,310027) 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1994年第1期55-64,共10页
In this paper we consider the Dirichlet problems of a non-uniformly digenerate elliptic equations of the formwhose prototype iswhere n C 1 N is a bounded domain,0<b(x)<1,0<o<P.We establish that if Aand B a... In this paper we consider the Dirichlet problems of a non-uniformly digenerate elliptic equations of the formwhose prototype iswhere n C 1 N is a bounded domain,0<b(x)<1,0<o<P.We establish that if Aand B are under some structure conditions and 0<or S P<max{aam +k,o+1}tthen there exists a CI+o-solution of(0.1)associated with the Dirichlet boundary dsta. 展开更多
关键词 elliptic equation Non-uniformly Degenerate.
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Entropy Formulation for Triply Nonlinear Degenerate Elliptic-Parabolic-Hyperbolic Equation with Zero-Flux Boundary Condition
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作者 Mohamed Karimou Gazibo 《Journal of Applied Mathematics and Physics》 2023年第4期933-948,共16页
In this note, we investigated existence and uniqueness of entropy solution for triply nonlinear degenerate parabolic problem with zero-flux boundary condition. Accordingly to the case of doubly nonlinear degenerate pa... In this note, we investigated existence and uniqueness of entropy solution for triply nonlinear degenerate parabolic problem with zero-flux boundary condition. Accordingly to the case of doubly nonlinear degenerate parabolic hyperbolic equation, we propose a generalization of entropy formulation and prove existence and uniqueness result without any structure condition. 展开更多
关键词 Degenerate elliptic-Parabolic Hyerbolic equation Zero-Flux Boundary Condition Structure Condition Entropy Formulation Multi-Step Approximation Nonlinear Semigroup Theories Integral and Mild Solution
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THE EXPONENTIAL PROPERTY OF SOLUTIONS BOUNDED FROM BELOW TO DEGENERATE EQUATIONS IN UNBOUNDED DOMAINS
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作者 Lidan WANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第1期323-348,共26页
This paper is focused on studying the structure of solutions bounded from below to degenerate elliptic equations with Neumann and Dirichlet boundary conditions in unbounded domains.After establishing the weak maximum ... This paper is focused on studying the structure of solutions bounded from below to degenerate elliptic equations with Neumann and Dirichlet boundary conditions in unbounded domains.After establishing the weak maximum principles,the global boundary Holder estimates and the boundary Harnack inequalities of the equations,we show that all solutions bounded from below are linear combinations of two special solutions(exponential growth at one end and exponential decay at the other)with a bounded solution to the degenerate equations. 展开更多
关键词 degenerate elliptic equations unbounded domains boundary Harnack inequalities
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Hlder continuity for solutions of elltptic equations involving measures
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作者 LiangXiting LuYouwen 《怀化师专学报》 1996年第5期34-43,共10页
The Hoider continuity is proved to bounded solutions of degenerate elliptic e-quations involving measures. The structural conditions of the equation are more general and therestrictions on the structural coofficients ... The Hoider continuity is proved to bounded solutions of degenerate elliptic e-quations involving measures. The structural conditions of the equation are more general and therestrictions on the structural coofficients are weaker. 展开更多
关键词 包含测度 椭圆型方程解 Hoolder连续性 结构系数
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一类退化椭圆方程的耗散系数识别问题
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作者 张霁澳 杜润梅 《吉林大学学报(理学版)》 CAS 北大核心 2024年第5期1037-1042,共6页
首先,考虑一类退化椭圆方程的耗散系数识别问题,通过把未知的耗散系数视为控制函数,把方程的解视为状态变量,定义目标泛函为状态与测量值的误差与人工正则项的和,将系数识别问题转化为最优控制问题.其次,利用最优控制问题的研究方法研... 首先,考虑一类退化椭圆方程的耗散系数识别问题,通过把未知的耗散系数视为控制函数,把方程的解视为状态变量,定义目标泛函为状态与测量值的误差与人工正则项的和,将系数识别问题转化为最优控制问题.其次,利用最优控制问题的研究方法研究系数识别问题,给出最优控制的表达式,并证明在适当条件下最优控制的唯一性. 展开更多
关键词 退化椭圆方程 系数识别 最优控制
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一类退化椭圆方程解的存在性与爆破行为
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作者 刘航 田书英 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2024年第3期282-291,共10页
研究了一类具有位势函数的锥形退化椭圆方程。通过探究约束极小化问题,建立了方程基态解的存在性定理,并分析了其爆破行为。证明了当参数满足一定条件时,约束极小化问题至少存在1个可达元,但当参数不满足此条件时,不存在可达元。详细分... 研究了一类具有位势函数的锥形退化椭圆方程。通过探究约束极小化问题,建立了方程基态解的存在性定理,并分析了其爆破行为。证明了当参数满足一定条件时,约束极小化问题至少存在1个可达元,但当参数不满足此条件时,不存在可达元。详细分析了当参数趋近于临界值时,可达元的爆破行为。 展开更多
关键词 退化椭圆方程 约束极小化问题 基态解
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一类退化椭圆方程跳跃问题解的存在性
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作者 安毕军 张家锋 《贵州工程应用技术学院学报》 2024年第3期22-29,共8页
利用紧自伴算子的谱理论、Schechter的环绕定理和变分方法证明了一类退化椭圆方程跳跃问题解的存在性,在一定程度上丰富了相关文献的一些相关结果。
关键词 退化椭圆方程 环绕定理 跳跃问题 解的存在性
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一类超二次退化椭圆方程非平凡解的存在性 被引量:4
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作者 安育成 索洪敏 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2014年第9期1284-1288,共5页
为获得退化椭圆方程在超二次条件下非平凡解的存在性,利用紧自伴算子的谱理论,研究退化椭圆方程对应特征值问题,给出特征值和对应的特征函数的性态;根据微分方程中的变分方法,建立退化椭圆方程对应的变分结构,利用临界点理论中的局部环... 为获得退化椭圆方程在超二次条件下非平凡解的存在性,利用紧自伴算子的谱理论,研究退化椭圆方程对应特征值问题,给出特征值和对应的特征函数的性态;根据微分方程中的变分方法,建立退化椭圆方程对应的变分结构,利用临界点理论中的局部环绕定理,获得了一些新的可解性条件,统一和推广了已有文献的一些结果. 展开更多
关键词 退化椭圆方程 变分方法 局部环绕定理 超二次条件 非平凡解
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一类退化半线性椭圆方程的Pontryagin最大值原理 被引量:2
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作者 张敬 周莉 郭金龙 《黑龙江大学自然科学学报》 CAS 北大核心 2015年第6期740-745,共6页
研究一类由退化半线性椭圆方程所支配的分布参数系统的最优控制问题。由于系统的退化性,当退化点集为单点集时,利用正则化方法得到正则化方程解的一些一致估计,再通过一个逼近过程证明了非退化系统最优控制的存在性。利用变分思想,得到... 研究一类由退化半线性椭圆方程所支配的分布参数系统的最优控制问题。由于系统的退化性,当退化点集为单点集时,利用正则化方法得到正则化方程解的一些一致估计,再通过一个逼近过程证明了非退化系统最优控制的存在性。利用变分思想,得到该分布参数系统的Pontryagin最大值原理。 展开更多
关键词 退化半线性椭圆方程 正则化方法 变分思想 Pontryagin最大值原理
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一类退缩的椭圆型方程弱解的正则性 被引量:2
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作者 冉启康 周树清 《高校应用数学学报(A辑)》 CSCD 北大核心 2000年第1期41-50,共10页
本文给出了一类退缩的拟线性椭圆型方程- Div[| Δu|p- 2 Δu + F(x,u)] = B(x,u, Δu)在W1,p(Ω)中弱解的C1,λloc (Ω)正则性,其中Ω为RN 中任一区域.
关键词 椭圆型方程 正则性 Poincsre不等式 弱解
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一类退化半线性椭圆方程支配系统的最优控制条件 被引量:1
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作者 张敬 高夯 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2015年第4期1-6,共6页
研究了一类由退化半线性椭圆方程所支配的分布参数系统的最优控制问题.当退化点集的测度为零时,利用正则化方法和变分思想,得到了该分布参数系统最优控制所满足的必要条件.
关键词 退化半线性椭圆方程 最优控制 正则化方法 变分思想 最大值原理
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一类二阶退化半线性椭圆型方程边值问题的适定性及解的正则性 被引量:4
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作者 何跃 《数学年刊(A辑)》 CSCD 北大核心 2004年第2期225-242,共18页
本文考虑一类二阶退化半线性椭圆型方程边值问题.由椭圆正则化方法建立能量不等式,利用紧性推理,Banach—Saks定理,弱解与强解一致性,解常微分方程,椭圆型方程正则性定理,迭代方法.极值原理和Fredholm—Riesz-Schauder理论,可得相应线... 本文考虑一类二阶退化半线性椭圆型方程边值问题.由椭圆正则化方法建立能量不等式,利用紧性推理,Banach—Saks定理,弱解与强解一致性,解常微分方程,椭圆型方程正则性定理,迭代方法.极值原理和Fredholm—Riesz-Schauder理论,可得相应线性问题适定性及解的高阶正则性;再由Moser引理和Banach不动点定理可得半线性问题解的存在性.这类问题与几何中无穷小等距形变刚性问题密切相关,其高阶正则性解的存在性对几何应用尤为重要. 展开更多
关键词 退化半线性椭圆型方程 适定性 正则性 先验估计
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退化椭圆型方程Dirichlet问题的概率数值解法 被引量:1
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作者 王刚 杨海亮 《内蒙古大学学报(自然科学版)》 CAS CSCD 1990年第1期17-23,共7页
A.Friedman 在参考文献中给出了退化椭圆型方程 Dirichlet 问题解的概率表达式,本文在此基砷上,给出了它的概率数值解及其误差估计.
关键词 退化 椭圆方程 概率数值解法 误差
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