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CLASSIFICATION AND EXISTENCE OF POSITIVE SOLUTIONS OF SECOND ORDER NONLINEAR DIFFERENTIAL EQUATIONS WITH DELAY DEPENDING ON THE UNKNOWN FUNCTION 被引量:5
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作者 LiWantong DongZhongqi 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期403-411,共9页
A class of second order nonlinear differential equations with delay depenging on the unknown function of the fromin the case where ∫0∞ ds/r(s) < ∞ is studied. Various classifications of their eventually positive... A class of second order nonlinear differential equations with delay depenging on the unknown function of the fromin the case where ∫0∞ ds/r(s) < ∞ is studied. Various classifications of their eventually positive solutions are given in terms of their asymptotic magnitudes, and necessary as well as sufficient conditions for the existence of these solutions are also obtained. 展开更多
关键词 Nonlinear differential equation with delay eventually positive solution asymptotic behavior fixed point theorem
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MULTIPLICITY AND CONCENTRATION BEHAVIOUR OF POSITIVE SOLUTIONS FOR SCHRDINGER-KIRCHHOFF TYPE EQUATIONS INVOLVING THE p-LAPLACIAN IN R^N 被引量:2
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作者 贾慧芳 李工宝 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期391-418,共28页
In this article, we study the multiplicity and concentration behavior of positive solutions for the p-Laplacian equation of SchrSdinger-Kirchhoff type -εpM(εp-N∫RN|△u|p)△pu+v(x|u|p-2u=f(u)in RN, where ... In this article, we study the multiplicity and concentration behavior of positive solutions for the p-Laplacian equation of SchrSdinger-Kirchhoff type -εpM(εp-N∫RN|△u|p)△pu+v(x|u|p-2u=f(u)in RN, where △p is the p-Laplacian operator, 1 〈 p 〈 N, M : R+ → R+ and V : RN →R+ are continuous functions, ε is a positive parameter, and f is a continuous function with subcritical growth. We assume that V satisfies the local condition introduced by M. del Pino and P. Felmer. By the variational methods, penalization techniques, and Lyusternik- Schnirelmann theory, we prove the existence, multiplicity, and concentration of solutions for the above equation. 展开更多
关键词 SchrSdinger-Kirchhoff type equation variational methods multiple positive solutions concentrating solution penalization method
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Some Equations for the External Space and Their Implications on the Inverse Cone Concept and the Geometry of the Physical Universe
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作者 J. G. Lartigue 《Journal of Modern Physics》 2020年第7期1005-1012,共8页
In previous works, they were proposed a photonic model of the Big Bang<a href="#ref1"> [1] </a>and several parameters derived from the Hubble-Lemaitre equation <a href="#ref2">[2]... In previous works, they were proposed a photonic model of the Big Bang<a href="#ref1"> [1] </a>and several parameters derived from the Hubble-Lemaitre equation <a href="#ref2">[2]</a>. Since these parameters result higher than the classical ones and, otherwise, the General Theory of Relativity does not apply far away the Physical Universe, in this paper, it will be revised the adequacy of such parameters in the external Space and their influence on the relativistic concept of the cone of time. As well, it will be intended to define the Physical Universe geometry accordingly to a thermo-dynamical analysis of the Big Bang. 展开更多
关键词 De Sitter Equation the inverse Time Cone Big Bang Characteristics
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Asymptotic Behavior and Nonexistence of Positive Solutions of Delay Difference Equations
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作者 彭名书 徐千里 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期25-30,共6页
目的讨论一类带可变系数二阶非线性中立型时滞差分方程正解所具有的性质.方法通过运用差分不等式及几个常用不等式,建立了两个引理.结果与结论获得了有关此类方程正解的渐近性质及不存在正解的新准则,推广并改善了最近文献的某些结... 目的讨论一类带可变系数二阶非线性中立型时滞差分方程正解所具有的性质.方法通过运用差分不等式及几个常用不等式,建立了两个引理.结果与结论获得了有关此类方程正解的渐近性质及不存在正解的新准则,推广并改善了最近文献的某些结果,同时还给出了具体的实例,以说明结果的实用、精确和重要. 展开更多
关键词 振动 渐近性 正解 中立型时滞差分方程 非线性
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Hermite Positive Definite Solution of the Quaternion Matrix Equation Xm + B*XB = C
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作者 Yiwen Yao Guangmei Liu +1 位作者 Yanting Zhang Jingpin Huang 《Journal of Applied Mathematics and Physics》 2023年第11期3760-3772,共13页
This paper discusses the necessary and sufficient conditions for the existence of Hermite positive definite solutions of the quaternion matrix equation X<sup>m</sup>+ B*XB = C (m > 0) and its iterative ... This paper discusses the necessary and sufficient conditions for the existence of Hermite positive definite solutions of the quaternion matrix equation X<sup>m</sup>+ B*XB = C (m > 0) and its iterative solution method. According to the characteristics of the coefficient matrix, a corresponding algebraic equation system is ingeniously constructed, and by discussing the equation system’s solvability, the matrix equation’s existence interval is obtained. Based on the characteristics of the coefficient matrix, some necessary and sufficient conditions for the existence of Hermitian positive definite solutions of the matrix equation are derived. Then, the upper and lower bounds of the positive actual solutions are estimated by using matrix inequalities. Four iteration formats are constructed according to the given conditions and existence intervals, and their convergence is proven. The selection method for the initial matrix is also provided. Finally, using the complexification operator of quaternion matrices, an equivalent iteration on the complex field is established to solve the equation in the Matlab environment. Two numerical examples are used to test the effectiveness and feasibility of the given method. . 展开更多
关键词 QUATERNION Matrix Equation Hermite positive Definite Solution Matrix Inequality ITERATIVE CONVERGENCE
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PROPER SPLITTINGS FOR RESTRICTED LINEAR EQUATIONS AND THE GENERALIZED INVERSE A_(T,S)~2 被引量:2
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作者 王国荣 魏益民 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1998年第1期1-13,共13页
This paper presents a proper splitting iterative method for comparing the general restricted linear euqations Ax=b, x ∈T (where, b ∈AT, and T is an arbitrary but fixed subspace of C<sup>m</sup>) and th... This paper presents a proper splitting iterative method for comparing the general restricted linear euqations Ax=b, x ∈T (where, b ∈AT, and T is an arbitrary but fixed subspace of C<sup>m</sup>) and the generalized in A<sub>T,S</sub> For the special case when b ∈AT and dim(T)=dim(AT), this splitting iterative methverse A<sub>T,S</sub> hod converges to A<sub>T,S</sub>b (the unique solution of the general restricted system Ax=bx ∈T). 展开更多
关键词 PROPER SPLITTING RESTRICTED linear equations the generalized inverse A2T S.
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THE EXISTENCE AND LOCAL UNIQUENESS OF MULTI-PEAK POSITIVE SOLUTIONS TO A CLASS OF KIRCHHOFF EQUATION 被引量:4
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作者 李工宝 牛亚慧 《Acta Mathematica Scientia》 SCIE CSCD 2020年第1期90-112,共23页
In the present paper,we consider the nonlocal Kirchhoff problem-(ε^2a+εb∫|■u|^2)Δu+u=Q(x)u^p,u>0 in R^3,,where a,b>0,1<p<5 andε>0 is a parameter.Under some assumptions on Q(x),we show the existenc... In the present paper,we consider the nonlocal Kirchhoff problem-(ε^2a+εb∫|■u|^2)Δu+u=Q(x)u^p,u>0 in R^3,,where a,b>0,1<p<5 andε>0 is a parameter.Under some assumptions on Q(x),we show the existence and local uniqueness of positive multi-peak solutions by LyapunovSchmidt reduction method and the local Pohozaev identity method,respectly. 展开更多
关键词 KIRCHHofF equations multi-peak positive solutions LOCAL UNIQUENESS LOCAL Pohozaev identity Lyapunov-Schmidt reduction
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EXISTENCE OF THE MINIMAL POSITIVE SOLUTION OF SOME NONLINEAR ELLIPTIC SYSTEMS WHEN THE NONLINEARITY IS THE SUM OF A SUBLINEAR AND A SUPERLINEAR TERM 被引量:2
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作者 Nicolae Tarfulea (Department of Mathematics, the Pennsylvania State University, University Park, PA 16802, U S A) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第3期283-290,共8页
It is shown that there exists Λ>0 such that, for every λ∈(0,Λ), the semilinear elliptic system: - Δ u=λu|u| q-1 +u|u| p-1 -v inΩ, - Δ v=δu-γv in Ω, u=v=0 on Ω, where Ω∈R N(N≥2) is ... It is shown that there exists Λ>0 such that, for every λ∈(0,Λ), the semilinear elliptic system: - Δ u=λu|u| q-1 +u|u| p-1 -v inΩ, - Δ v=δu-γv in Ω, u=v=0 on Ω, where Ω∈R N(N≥2) is a bounded domain with smooth boundary and 0<q<1<p,has a minimal positive solution (u λ,v λ). Moreover: u λ and v λ are strictly increasing with respect to λ. 展开更多
关键词 reaction diffusion system positive solution nonlinear equation
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The Factorization Method to Solve a Class of Inverse Potential Scattering Problems for Schrdinger Equations 被引量:2
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作者 LI YUAN MA FU-MING 《Communications in Mathematical Research》 CSCD 2010年第4期321-336,共16页
This paper is concerned with the inverse scattering problems for Schrdinger equations with compactly supported potentials.For purpose of reconstructing the support of the potential,we derive a factorization of the sca... This paper is concerned with the inverse scattering problems for Schrdinger equations with compactly supported potentials.For purpose of reconstructing the support of the potential,we derive a factorization of the scattering amplitude operator A and prove that the ranges of (A* A) ^1/4 and G which maps more general incident fields than plane waves into the scattering amplitude coincide.As an application we characterize the support of the potential using only the spectral data of the operator A. 展开更多
关键词 factorization method inverse scattering Schrdinger equation interior transmission problem
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GLOBAL ATTRACTIVITY OF NEUTRAL DIFFERENCE EQUATIONS WITH POSITIVE AND NEGATIVE COEFFICIENTS 被引量:2
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作者 Li Xiaoping Jiang Jianchu Gao PingDept. of Math., Loudi Teacher’s College, Loudi 417000,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第3期258-266,共9页
A neutral difference equation with positive and negative coefficientsΔ(x n-c nx n-k )+p nx n-l -q nx n-r =0, n=0,1,2,...,is considered and a sufficient condition for the global attractivity of the ze... A neutral difference equation with positive and negative coefficientsΔ(x n-c nx n-k )+p nx n-l -q nx n-r =0, n=0,1,2,...,is considered and a sufficient condition for the global attractivity of the zero solution of this equation is obtained, which improves and extends the all known results in the literature. 展开更多
关键词 global attractivity neutral difference equations positive and negative coefficients.
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FINITE TIME BLOW UP OF THE SOLUTIONS TO BOUSSINESQ EQUATION WITH LINEAR RESTORING FORCE AND ARBITRARY POSITIVE ENERGY 被引量:2
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作者 nikolay kutev natalia kolkovska milena dimova 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期881-890,共10页
Finite time blow up of the solutions to Boussinesq equation with linear restoring force and combined power nonlinearities is studied. Sufficient conditions on the initial data for nonexistence of global solutions are ... Finite time blow up of the solutions to Boussinesq equation with linear restoring force and combined power nonlinearities is studied. Sufficient conditions on the initial data for nonexistence of global solutions are derived. The results are valid for initial data with arbitrary high positive energy. The proofs are based on the concave method and new sign preserving functionals. 展开更多
关键词 Boussinesq equation with linear restoring force finite time blow up arbitrary high positive energy combined power nonlinearities sign preserving functionals
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EPSILON-ALGORITHM AND ETA-ALGORITHM OF GENERALIZED INVERSE FUNCTION-VALUED PAD APPROXIMANTS USING FOR SOLUTION OF INTEGRAL EQUATIONS 被引量:1
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作者 李春景 顾传青 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第2期221-229,共9页
Two efficient recursive algorithms epsilon_algorithm and eta_algorithm are introduced to compute the generalized inverse function_valued Padé approximants. The approximants were used to accelerate the convergenc... Two efficient recursive algorithms epsilon_algorithm and eta_algorithm are introduced to compute the generalized inverse function_valued Padé approximants. The approximants were used to accelerate the convergence of the power series with function_valued coefficients and to estimate characteristic value of the integral equations. Famous Wynn identities of the Pad approximants is also established by means of the connection of two algorithms. 展开更多
关键词 generalized inverse function_valued Padé approximant epsilon_algorithm eta_algorithm integral equations
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A CONTINUATION HOMOTOPY METHOD FOR THE INVERSE PROBLEM OF OPERATOR IDENTIFICATION AND ITS APPLICATION 被引量:1
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作者 韩波 刘家琦 卢惠林 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第1期69-75,共7页
A new widly convergent method for solving the problem of operator identification is illustrated. Numerical simulations are carried out to test the feasibility and to study the general characteristics of the technique ... A new widly convergent method for solving the problem of operator identification is illustrated. Numerical simulations are carried out to test the feasibility and to study the general characteristics of the technique without the real measurement data. This technique is a direct application of the continuation homo-topy method for solving nonlinear systems of equations. It is found that this method does give excellent results in solving the inverse problem of the elliptic differential equations. 展开更多
关键词 inverse Problem Homotopy Method Elliptic Differential equations.
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STRUCTURE OF NONNEGATIVE NONTRIVIAL AND POSITIVE SOLUTIONS OF SINGULARLY PERTURBED p-LAPLACE EQUATIONS 被引量:1
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作者 张正策 李开泰 LINZong-chi 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第8期929-936,共8页
Structure of nonnegative nontrivial and positive solutions was precisely studied for some singularly perturbed p-Laplace equations. By virtue of sub- and supersolution method, it is shown that there are many nonnegati... Structure of nonnegative nontrivial and positive solutions was precisely studied for some singularly perturbed p-Laplace equations. By virtue of sub- and supersolution method, it is shown that there are many nonnegative nontrivial spike-layer solutions and positive intermediate spike-layer solutions. Moreover, the upper and lower bound on the measure of each spike-layer were estimated when the parameter is sufficiently small. 展开更多
关键词 p-Laplace equation nonnegative nontrivial solution positive solution spike-layer solution sub- and supersolution
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The Generalized Inverse of Singular Integral Operators on an Open Arc and Its Applications 被引量:1
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作者 Li Hong-yan Wang Xiao-ling 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第4期747-753,共7页
After choosing weight functions suitably, we define a Banach spaceH ω μ (L) and discuss the generalized inverse of singular integral operators on an open arc. Using the generalized inverse, we obtain the solutions f... After choosing weight functions suitably, we define a Banach spaceH ω μ (L) and discuss the generalized inverse of singular integral operators on an open arc. Using the generalized inverse, we obtain the solutions for the following singular integral equation 展开更多
关键词 open arc generalized inverse singular integral equations with kernel having singularities of order one
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Existence and Multiple of Positive Solution for Nonlinear Fractional Difference Equations with Parameter 被引量:1
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作者 Youji Xu 《Journal of Applied Mathematics and Physics》 2015年第7期757-760,共4页
Let,. We study the existence and multiple positive solutions of n-th nonlinear discrete fractional boundary value problem of the form By using a fixed-point theorem on cone, the parameter intervals of problem is estab... Let,. We study the existence and multiple positive solutions of n-th nonlinear discrete fractional boundary value problem of the form By using a fixed-point theorem on cone, the parameter intervals of problem is established. 展开更多
关键词 Fractional Difference equations PARAMETER INTERVALS positive Solution FIXED-POINT theorem
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The General and Centro(Kewsy) Symmetric Solutions to a System of Matrix Equations over an Arbitrary Skew Field 被引量:3
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作者 QIN Jian-guo SONG Guang-ai 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期66-70,共5页
必要、足够的条件在任意的斜域上为一般解决方案,中心对称的解决方案,和线性矩阵方程的一个系统的 centroskewsymmetric 答案的存在被给。系统的如此的答案的代表也被导出。
关键词 矩阵方程系统 内逆矩阵 均衡矩阵 反称域
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THE SYMMETRIC AND SYMMETRIC POSITIVE SEMIDEFINITE SOLUTIONS OF LINEAR MATRIX EQUATION——B^TXB = D ON LINEAR MANIFOLDS 被引量:4
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作者 邓远北 胡锡炎 张磊 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2003年第2期186-192,共7页
This paper discusses the solutions of the linear matrix equation BT X B=Don some linear manifolds.Some necessary and sufficient conditions for the existenceof the solution and the expression of the general solution ar... This paper discusses the solutions of the linear matrix equation BT X B=Don some linear manifolds.Some necessary and sufficient conditions for the existenceof the solution and the expression of the general solution are given.And also someoptimal approximation solutions are discussed. 展开更多
关键词 半定解 线性矩阵方程 线性流形 半定矩阵 正交矩阵
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Positive solutions of nonlinear elastic beam equations with a fixed end and a movable end 被引量:3
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作者 姚庆六 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第5期545-548,共4页
The existence of n positive solutions is studied for a class of fourth-order elastic beam equations where one end is fixed and other end is movable. Here, n is an arbitrary natural number. Our results show that the cl... The existence of n positive solutions is studied for a class of fourth-order elastic beam equations where one end is fixed and other end is movable. Here, n is an arbitrary natural number. Our results show that the class of equations may have n positive solutions provided the “heights” of the nonlinear term are appropriate on some bounded sets. 展开更多
关键词 非线性弹性梁方程 边界值问题 正解 存在性 多样性
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THE NECESSARY AND SUFFICIENT CONDITIONS FOR THE SOLVABILITY OF A CLASS OF THE MATRIX INVERSE PROBLEM
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作者 廖安平 张磊 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1998年第2期195-200,共6页
Censider the solutions of the matrix inverse problem, which are symmetric positive semide finite on a subspace. Necessary and sufficient conditions for the solvability, as well as the general solution are obtained. Th... Censider the solutions of the matrix inverse problem, which are symmetric positive semide finite on a subspace. Necessary and sufficient conditions for the solvability, as well as the general solution are obtained. The best approximate solution by the above solution set is given. Thus the open problem in [1] is solved. 展开更多
关键词 MATRIX inverse problem SYMMETRIC positive SEMIDEFINITE MATRIX best APPROXIMATE solution.
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