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Existence of Positive Solution for Superlinear Semipositone Singular Second-order m-point Boundary Value Problem 被引量:4
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作者 ZHANG Xing-qiu 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期151-158,共8页
由使用固定的点定理,积极答案的存在为 superlinear semipositone 被认为单个m点边界价值问题--(n)(x)= f ( x ,(x))+ g (x), 0 < x < 1 ,( 0 ) =0 ,( 1 )= m-2i=1 ai (i),吗在哪儿(L)(x)=( p (x)“(x))”+ q (x)(x)和 i ... 由使用固定的点定理,积极答案的存在为 superlinear semipositone 被认为单个m点边界价值问题--(n)(x)= f ( x ,(x))+ g (x), 0 < x < 1 ,( 0 ) =0 ,( 1 )= m-2i=1 ai (i),吗在哪儿(L)(x)=( p (x)“(x))”+ q (x)(x)和 i ( 0 , 1 )与 0 < 1 < 2 << m-2 < 1 , ai R+, f C [( 0,1 )???嘠???畭瑬杩楲???????牥業整?? 展开更多
关键词 SEMIPOSITONE SUPERlineAR 单个 m 点边界价值 固定的点定理 积极答案
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BIFURCATION OF SINGULAR POINTS NEAR A DOUBLE FOLD POINT INZ_2 -SYMMETRIC NONLINEAR EQUATIONS
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作者 吴微 吴柏生 李荣华 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1993年第1期101-115,共15页
We consider the bifurcation of singular points near a double fold point in Z2 -symmetric nonlinear equations with two parameters,where the linearization has a two dimensional null space spanned by a symmetric null vec... We consider the bifurcation of singular points near a double fold point in Z2 -symmetric nonlinear equations with two parameters,where the linearization has a two dimensional null space spanned by a symmetric null vector and an ami-symmetric null vector. In particular, we show the existence of a turning point path and a pitchfork point path passing ihrough the double fold point and they are the only singular points nearby. Their nondegeneracy is confirmed. A supporting numerical example is also provided. The main tools for our analysis as well as the compulation are some extended systems. 展开更多
关键词 DOUBLE FOLD pointS Z2 -symmetry BIFURCATION of nonlinear equations singular pointS turning pointS pitchfork pointS extended systems.
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Regular-Singular Crossings on Nonlinear Systems with Turning Point
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作者 Zhang Hanlin (Beijing Polytechnic University) Zhang Heping (Beijing Electric Power College) 《Advances in Manufacturing》 SCIE CAS 1998年第3期21-23,共3页
We consider in this paper the boundary value problems of nonlinear systems the form εY″=F(t,Y,Y′,ε), -1<t<1, Y(-1,ε)=A(ε), Y(1,ε)=B(ε). Supoosing some or all of the components of F , that is, ... We consider in this paper the boundary value problems of nonlinear systems the form εY″=F(t,Y,Y′,ε), -1<t<1, Y(-1,ε)=A(ε), Y(1,ε)=B(ε). Supoosing some or all of the components of F , that is, f i satisfy 2 f y′ 2 i t =0 =0, we say that F possesses a generalized turning point at t =0. Our goal is to give sufficient conditions for the existence of solution of the problems and to study the asymptotic behavior of the solution when F possesses a generalized turning point at t =0. We mainly discuss regular singular crossings. 展开更多
关键词 turning point regular singular crossing differential inequality
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To Theory One Class Linear Model Noclassical Volterra Type Integral Equation with Left Boundary Singular Point
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作者 Nusrat Rajabov 《Applied Mathematics》 2013年第9期1301-1312,共12页
In this work, we investigate one class of Volterra type integral equation, in model case, when kernels have first order fixed singularity and logarithmic singularity. In detail study the case, when n = 3. In depend of... In this work, we investigate one class of Volterra type integral equation, in model case, when kernels have first order fixed singularity and logarithmic singularity. In detail study the case, when n = 3. In depend of the signs parameters solution to this integral equation can contain three arbitrary constants, two arbitrary constants, one constant and may have unique solution. In the case when general solution of integral equation contains arbitrary constants, we stand and investigate different boundary value problems, when conditions are given in singular point. Besides for considered integral equation, the solution found cane represented in generalized power series. Some results obtained in the general model case. 展开更多
关键词 NEOCLASSICAL VOLTERRA Type Integral Equation LEFT BOUNDARY singular point BOUNDARY Value Problems
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NUMERICAL SOLUTION OF QUASILINEAR SINGULARLY PERTURBED ORDINARY DIFFERENTIAL EQUATION WITHOUT TURNING POINTS
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作者 林平 苏煜城 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第11期1005-1010,共6页
In this paper we consider a quasilinear second order ordinary diferential equation with a small parameter Firstly an approximate problem is constructed. Then an iterative procedure is developed. Finally we give an alg... In this paper we consider a quasilinear second order ordinary diferential equation with a small parameter Firstly an approximate problem is constructed. Then an iterative procedure is developed. Finally we give an algorithm whose accuracy is good for arbitrary e>0 . 展开更多
关键词 NUMERICAL SOLUTION OF QUASIlineAR singularLY PERTURBED ORDINARY DIFFERENTIAL EQUATION WITHOUT TURNING pointS
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Symmetric Positive Solutions of Nonlinear Singular Second-order Three-point Boundary Value Problem
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作者 吴红萍 《Chinese Quarterly Journal of Mathematics》 2015年第3期358-365,共8页
In this paper, the second-order three-point boundary value problem u(t) + λa(t)f(t, u(t)) = 0, 0 < t < 1,u(t) = u(1- t), u(0)- u(1) = u(12)is studied, where λ is a positive parameter, under various assumption ... In this paper, the second-order three-point boundary value problem u(t) + λa(t)f(t, u(t)) = 0, 0 < t < 1,u(t) = u(1- t), u(0)- u(1) = u(12)is studied, where λ is a positive parameter, under various assumption on a and f, we establish intervals of the parameter λ, which yield the existence of positive solution, our proof based on Krasnosel'skii fixed-point theorem in cone.{u"(t)+λa(t)f(t,u(t))=0,0<t<1,u(t)=u(1-t),u′(0)-u′(1)=u(1/2)is studied,where A is a positive parameter,under various assumption on a and f,we establish intervals of the parameter A,which yield the existence of positive solution,our proof based on Krasnosel'skii fixed-point theorem in cone. 展开更多
关键词 three-point boundary value problem FIXED-point THEOREM singular POSITIVE solutions
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Singular perturbation of a second-order three-point boundary value problem for nonlinear systems
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作者 林晓洁 刘文斌 《Journal of Shanghai University(English Edition)》 CAS 2009年第1期16-19,共4页
This paper deals with the existence of solutions to a singularly perturbed second-order three-point boundary value problem for nonlinear differential systems. The authors construct an appropriate generalized lower- an... This paper deals with the existence of solutions to a singularly perturbed second-order three-point boundary value problem for nonlinear differential systems. The authors construct an appropriate generalized lower- and upper-solution pair, a concept defined in this paper, and employ the Nagumo conditions and algebraic boundary layer functions to ensure the existence of solutions of the problem. The uniformly valid asymptotic estimate of the solutions is given as well. The differential systems have nonlinear dependence on all order derivatives of the unknown. 展开更多
关键词 singular perturbation nonlinear systems three-point boundary value problem upper and lower solutions
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EXISTENCE OF SOLUTIONS FOR A SINGULARLY PERTURBED BOUNDARY VALUE PROBLEM FOR THE THIRD ORDER SEMI-LINEAR DIFFERENTIAL EQUATION WITH A TURNING POINT
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作者 蔡建平 林宗池 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第12期1089-1093,共5页
In this paper, by using the techniques of differential inequalities, we prove the existence of the solutions of a singularly perturbed boundary value problem for the third order semilinear differential equation with a... In this paper, by using the techniques of differential inequalities, we prove the existence of the solutions of a singularly perturbed boundary value problem for the third order semilinear differential equation with a turning point. 展开更多
关键词 turning point SEMI-lineAR singular perturbation
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MULTIPLE POSITIVE SOLUTIONS TO SINGULAR BOUNDARY VALUE PROBLEMS FOR SUPERLINEAR SECOND ORDER ODES 被引量:11
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作者 蒋达清 《Acta Mathematica Scientia》 SCIE CSCD 2002年第2期199-206,共8页
This paper deals with the existence of positive solutions to the singular boundary value problemwhere q(t) may be singular at t = 0 and t = 1, f(t,y) may be superlinear at y =∞ and singular, at y = 0.
关键词 singular boundary value problem existence SUPERlineAR the fixed point theorem
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MULTIPLE POSITIVE SOLUTIONS FOR FIRST ORDER IMPULSIVE SINGULAR INTEGRO-DIFFERENTIAL EQUATIONS ON THE HALF LINE 被引量:7
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作者 郭大钧 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2176-2190,共15页
In this paper, the author discusses the multiple positive solutions for an infinite boundary value problem of first order impulsive singular integro-differential equations on the half line by means of the fixed point ... In this paper, the author discusses the multiple positive solutions for an infinite boundary value problem of first order impulsive singular integro-differential equations on the half line by means of the fixed point theorem of cone expansion and compression with norm type. 展开更多
关键词 impulsive singular integro-differential equation infinite boundary valueproblem fixed point theorem of cone expansion and compression with normtype
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POSITIVE SOLUTIONS FOR SINGULAR BVPs ON THE POSITIVE HALF-LINE ARISING FROM EPIDEMIOLOGY AND COMBUSTION THEORY 被引量:2
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作者 Smaïl Djebali Ouiza Saïfi 闫宝强 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期672-694,共23页
In this work, we are concerned with the existence and multiplicity of positive solutions for singular boundary value problems on the half-line. Two problems from epi- demiology and combustion theory set on the positiv... In this work, we are concerned with the existence and multiplicity of positive solutions for singular boundary value problems on the half-line. Two problems from epi- demiology and combustion theory set on the positive half-line are investigated upper and lower solution techniques combined with fixed point index on cones in priate Banach spaces. The results complement recent ones in the literature. We use appropriate Banach spaces. The results complement recent ones in the literature. 展开更多
关键词 Fixed points index positive solution singular problem CONE lower andupper solution HALF-line
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Dynamic Response Analysis of the Equivalent Water Depth Truncated Point of the Catenary Mooring Line 被引量:3
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作者 ZHANG Huo-ming KONG Ling-bin +2 位作者 GUAN Wei-bing HUANG Sai-hua FANG Gui-sheng 《China Ocean Engineering》 SCIE EI CSCD 2017年第1期37-47,共11页
The real-time computer-controlled actuators are used to connect the truncated parts of moorings and risers in the active hybrid model testing system. This must be able to work in model-scale real time, based on feedba... The real-time computer-controlled actuators are used to connect the truncated parts of moorings and risers in the active hybrid model testing system. This must be able to work in model-scale real time, based on feedback input from the floater motions. Thus, mooring line dynamics and damping effects are artificially simulated in real time, based on a computer-based model of the problem. In consideration of the nonlinear characteristics of the sea platform catenary mooring line, the equations of the mooring line motion are formulated by using the lumped-mass method and the dynamic response of several points on the mooring line is investigated by the time and frequency domain analysis method. The dynamic response of the representative point on the mooring line is analyzed under the condition of two different corresponding upper endpoint movements namely sine wave excitation and random wave excitation. The corresponding laws of the dynamic response between the equivalent water depth truncated points at different locations and the upper endpoint are obtained, which can provide technical support for further study of the active hybrid model test. 展开更多
关键词 mooting line truncated point dynamic response lumped-mass method time domain simulation
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TWO POSITIVE SOLUTIONS TO THREE-POINT SINGULAR BOUNDARY VALUE PROBLEMS 被引量:3
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作者 李宇华 梁占平 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期29-38,共10页
In this article, we consider the existence of two positive solutions to nonlinear second order three-point singular boundary value problem: -u′′(t) = λf(t, u(t)) for all t ∈ (0, 1) subjecting to u(0) = ... In this article, we consider the existence of two positive solutions to nonlinear second order three-point singular boundary value problem: -u′′(t) = λf(t, u(t)) for all t ∈ (0, 1) subjecting to u(0) = 0 and αu(η) = u(1), where η ∈ (0, 1), α ∈ [0, 1), and λ is a positive parameter. The nonlinear term f(t, u) is nonnegative, and may be singular at t = 0, t = 1, and u = 0. By the fixed point index theory and approximation method, we establish that there exists λ* ∈ (0, +∞], such that the above problem has at least two positive solutions for any λ ∈ (0, λ*) under certain conditions on the nonlinear term f. 展开更多
关键词 Three-point singular boundary value problem positive solutions fixed point index
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A Singular Perturbation Method for Parametric Investigation on J-lay Installation of Deepwater Pipelines 被引量:3
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作者 王琴 段梦兰 +1 位作者 李海明 张庆元 《China Ocean Engineering》 SCIE EI CSCD 2013年第6期751-766,共16页
The maximum bending moment or curvature in the neighborhood of the touch down point (TDP) and the maximum tension at the top are two key parameters to be controlled during deepwater J-lay installation in order to en... The maximum bending moment or curvature in the neighborhood of the touch down point (TDP) and the maximum tension at the top are two key parameters to be controlled during deepwater J-lay installation in order to ensure the safety of the pipe-laying operation and the normal operation of the pipelines. In this paper, the non-linear governing differential equation for getting the two parameters during J-lay installation is proposed and solved by use of singular perturbation technique, from which the asymptotic expression of stiffened catenary is obtained and the theoretical expression of its static geometric configuration as well as axial tension and bending moment is derived. Finite element results are applied to verify this method. Parametric investigation is conducted to analyze the influences of the seabed slope, unit weight, flexural stiffness, water depth, and the pipe-laying tower angle on the maximum tension and moment of pipeline by this method, and the results show how to control the installation process by changing individual parameters. 展开更多
关键词 deepwater touch down point singular perturbation technique non-linear governing differential equation J-lay of pipeline geometric nonlinearity stiffened catenary
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MULTIPLE POSITIVE SOLUTIONS FOR SUPERLINEAR SECOND ORDER SINGULAR BOUNDARY VALUE PROBLEMS WITH DERIVATIVE DEPENDENCE 被引量:2
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作者 闫宝强 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期851-864,共14页
The existence of at least two positive solutions is presented for the singular second-order boundary value problem{1/p(t)( p(t)x′(t))′+Φ(t)f(t,x(t),p(t)x′(t))=0,0〈t〈1, limt→0 p(t)x′(t)=... The existence of at least two positive solutions is presented for the singular second-order boundary value problem{1/p(t)( p(t)x′(t))′+Φ(t)f(t,x(t),p(t)x′(t))=0,0〈t〈1, limt→0 p(t)x′(t)=0,x(1)=0by using the fixed point index, where f may be singular at x = 0 and px ′= 0. 展开更多
关键词 Boundary value problems singularITY fixed point index
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POSITIVE SOLUTIONS OF BOUNDARY VALUE PROBLEMS FOR SECOND-ORDER SINGULAR NONLINEAR DIFFERENTIAL EQUATIONS 被引量:2
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作者 LI Ren-gui(李仁贵) +1 位作者 LI Li-shan(刘立山) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第4期495-500,共6页
New existence results are presented for the singular second-order nonlinear boundary value problems u ' + g(t)f(u) = 0, 0 < t < 1, au(0) - betau ' (0) = 0, gammau(1) + deltau ' (1) = 0 under the cond... New existence results are presented for the singular second-order nonlinear boundary value problems u ' + g(t)f(u) = 0, 0 < t < 1, au(0) - betau ' (0) = 0, gammau(1) + deltau ' (1) = 0 under the conditions 0 less than or equal to f(0)(+) < M-1, m(1) < f(infinity)(-)less than or equal to infinity or 0 less than or equal to f(infinity)(+)< M-1, m(1) < f (-)(0)less than or equal to infinity where f(0)(+) = lim(u -->0)f(u)/u, f(infinity)(-)= lim(u --> infinity)f(u)/u, f(0)(-)= lim(u -->0)f(u)/u, f(infinity)(+) = lim(u --> infinity)f(u)/u, g may be singular at t = 0 and/or t = 1. The proof uses a fixed point theorem in cone theory. 展开更多
关键词 second-order singular boundary value problems positive solutions cone fixed point
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Precise integration method for a class of singular two-point boundary value problems 被引量:2
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作者 Wen-Zhi Zhang Pei-Yan Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期233-240,共8页
In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the met... In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations(ODEs) are transformed into homogeneous ODEs.Then the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction method.Finally numerical examples are elaboratedd to validate the present method. 展开更多
关键词 singular two point boundary value problem Precise integration method High order multiple perturbation method Reduction method
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A QUASILINEAR SINGULAR ELLIPTIC SYSTEM WITHOUT COOPERATIVE STRUCTURE 被引量:1
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作者 Dumitru MOTREANU Abdelkrim MOUSSAOUI 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期905-916,共12页
In this article, we investigate the existence of positive solutions of a singular quasilinear elliptic system for which the cooperative structure is not required. The approach is based on the Schauder fixed point theo... In this article, we investigate the existence of positive solutions of a singular quasilinear elliptic system for which the cooperative structure is not required. The approach is based on the Schauder fixed point theorem combined with perturbation arguments that involve the singular terms. 展开更多
关键词 singular system p-Laplacian Schauder's fixed point theorem bounded solution Moser iteration
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NEAR CRACK LINE ELASTIC-PLASTIC ANALYSIS FOR A CRACK LOADED BY ANTIPLANE POINT FORCES 被引量:1
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作者 吴承平 王成 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第12期1121-1126,共6页
In this paper, the improved near crack line analysis method proposed in Refs. [1]and [2] is used to investigate a mode Ⅲ crack loaded by antiplane point forces in aninfinite plate in an elastic-perfectly plastic sol... In this paper, the improved near crack line analysis method proposed in Refs. [1]and [2] is used to investigate a mode Ⅲ crack loaded by antiplane point forces in aninfinite plate in an elastic-perfectly plastic solid. The solutions of this paper aresufficiently precise near the crack line region because. the assumptions of the smallscale yielding theory have not been used and no other assumptions have been taken. 展开更多
关键词 mode Ⅲcrack near crack line analysis ELASTIC-PLASTIC antiplane point forces
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Evolution of emergent C-points,L-lines,and C-lines in free space 被引量:1
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作者 闫红卫 何德 吕百达 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期227-232,共6页
Polarization singularities,which emerge from the incoherent superposition of two vector electric fields with the same frequency,and their evolution in free space are studied analytically and illustrated by numerical e... Polarization singularities,which emerge from the incoherent superposition of two vector electric fields with the same frequency,and their evolution in free space are studied analytically and illustrated by numerical examples.It is shown that there exist C-points,L-lines,in particular,C-lines in incoherently superimposed two-dimensional wavefields.Usually,the C-lines are unstable and disappear during the free-space propagation.The motion,pair creation-annihilation process of the emergent C-points,as well as the distortion of the L-lines may take place,and the degree of polarization of the emergent C-points varies upon propagation and may be less than 1. 展开更多
关键词 vector singular optics emergent C-points L-lines and C-lines incoherent superposition degree of polarization
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