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Spectral clustering eigenvector selection of hyperspectral image based on the coincidence degree of data distribution
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作者 Zhongliang Ren Qiuping Zhai Lin Sun 《International Journal of Digital Earth》 SCIE EI 2023年第1期3489-3512,共24页
Spectral clustering is a well-regarded subspace clustering algorithm that exhibits outstanding performance in hyperspectral image classification through eigenvalue decomposition of the Laplacian matrix.However,its cla... Spectral clustering is a well-regarded subspace clustering algorithm that exhibits outstanding performance in hyperspectral image classification through eigenvalue decomposition of the Laplacian matrix.However,its classification accuracy is severely limited by the selected eigenvectors,and the commonly used eigenvectors not only fail to guarantee the inclusion of detailed discriminative information,but also have high computational complexity.To address these challenges,we proposed an intuitive eigenvector selection method based on the coincidence degree of data distribution(CDES).First,the clustering result of improved k-means,which can well reflect the spatial distribution of various types was used as the reference map.Then,the adjusted Rand index and adjusted mutual information were calculated to assess the data distribution consistency between each eigenvector and the reference map.Finally,the eigenvectors with high coincidence degrees were selected for clustering.A case study on hyperspectral mineral mapping demonstrated that the mapping accuracies of CDES are approximately 56.3%,15.5%,and 10.5%higher than those of the commonly used top,high entropy,and high relevance eigenvectors,and CDES can save more than 99%of the eigenvector selection time.Especially,due to the unsupervised nature of k-means,CDES provides a novel solution for autonomous feature selection of hyperspectral images. 展开更多
关键词 Eigenvector selection spectral clustering coincidence degree of data distribution hyperspectral mineral mapping
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Existence of Periodic Solutions for Generalized Liénard-Typed Functional Differential Equations
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作者 贺小明 葛渭高 单文锐 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期325-328,共4页
The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are ... The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are established for the existence of periodic solutions and some previous results are extended. 展开更多
关键词 functional differential equation periodic solution coincidence degree
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EXISTENCE OF POSITIVE SOLUTION FOR A TWO-PATCHES COMPETITION SYSTEM WITH DIFFUSION AND TIME DELAY AND FUNCTIONAL RESPONSE 被引量:12
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作者 LiBiwen ZengXianwu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期1-8,共8页
By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]... By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]′ 1 (t)=x 1(t)a 1(t)-b 1(t)x 1(t)-c 1(t)y(t)1+m(t)x 1(t)+D 1(t)[x 2(t)-x 1(t)], x [FK(W1*3/4。*2/3]′ 2 (t)=x 2(t)a 2(t)-b 2(t)x 2(t)-c 2(t)∫ 0 -τ k(s)x 2(t+s) d s+D 2(t)[x 1(t)-x 2(t)], y′(t)=y(t)a 3(t)-b 3(t)y(t)-c 3(t)x 1(t)1+m(t)x 1(t)is established, where a i(t),b i(t),c i(t)(i=1,2,3),m(t) and D i(t)(i=1,2) are all positive periodic continuous functions with period w >0, τ is a nonnegative constant and k(s) is a continuous nonnegative function on [- τ ,0]. 展开更多
关键词 periodic solutions competition diffusive system functional response continuation theorem of coincidence degree topological degree.
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Existence of two periodic solutions of a ratio-dependent Holling-Taner model with infinite delay and prey harvest 被引量:5
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作者 TIAN De-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期136-142,共7页
This paper considers a class of ratio-dependent Holling-Taner model with infinite delay and prey harvest, which is of periodic coefficients. By means of the coincidence degree theory, a set of sufficient conditions fo... This paper considers a class of ratio-dependent Holling-Taner model with infinite delay and prey harvest, which is of periodic coefficients. By means of the coincidence degree theory, a set of sufficient conditions for the existence of at least two positive periodic solutions of this model is established. 展开更多
关键词 Holling-Taner model RATIO-DEPENDENT HARVEST periodic solution coincidence degree.
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Periodic Solution for Diffusive Predator-Prey System with Functional Response 被引量:4
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作者 Li Bi\|wen 1,2 , Cheng Jian 1 1. Department of Mathematics, Hubei Normal University, Huangshi 435002, Hubei,China 2. School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期267-273,共7页
In this paper, a three species diffusive predator-prey model with functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence ... In this paper, a three species diffusive predator-prey model with functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for this system is established. 展开更多
关键词 diffusive model functional nesponse positive periodic solution continuation theorem of coincidence degree fopological degree
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EXISTENCE OF PERIODIC SOLUTIONS OF PLANAR SYSTEMS WITH FOUR DELAYS 被引量:3
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作者 Zhang Zhengqiu Wang ZhichengDept. of Appl. Math.,Hunan Univ.,Changsha 410082. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第4期355-363,共9页
The sufficient condition for the existence of non constant periodic solutions of the following planar system with four delays are obtained:x [FK(W1*1。*3/4]′ 1(t)=-a 0x α 1(t)+a 1f 1(x 1(t-τ 1),x 2... The sufficient condition for the existence of non constant periodic solutions of the following planar system with four delays are obtained:x [FK(W1*1。*3/4]′ 1(t)=-a 0x α 1(t)+a 1f 1(x 1(t-τ 1),x 2(t-τ 2)), x [FK(W1*1。*3/4]′ 2(t)=-b 0x α 2(t)+b 1f 2(x 1(t-τ 3),x 2(t-τ 4)).This approach is based on the continuation theorem of the coincidence degree, and the a priori estimate of periodic solutions. 展开更多
关键词 Planar systems non constant periodic solutions coincidence degree the a priori estimate.
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2π-periodic Solution for a Kind High Order Delay Duffing Equation 被引量:4
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作者 LIN Wen-xian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期85-89,共5页
In this paper, the high order delay Duffing equation ax^(2n) +bx+g(x(t-r)) = p(t) are considered,using the theory of coincidence degree, the sufficient condition for its there being at least a 2π-periodic s... In this paper, the high order delay Duffing equation ax^(2n) +bx+g(x(t-r)) = p(t) are considered,using the theory of coincidence degree, the sufficient condition for its there being at least a 2π-periodic solution is obtained. 展开更多
关键词 Duffing equation periodic solution coincidence degree
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EXISTENCE OF SOLUTIONS FOR HIGHER ORDER MULTI-POINT BOUNDARY VALUE PROBLEM AT RESONANCE 被引量:3
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作者 林晓洁 杜增吉 葛渭高 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第5期705-711,共7页
Using the theory of coincidence degree, a class of higher order multi-point boundary value problem for ordinary differential equations are studied. Under the boundary conditions satisfying the resonance case, some new... Using the theory of coincidence degree, a class of higher order multi-point boundary value problem for ordinary differential equations are studied. Under the boundary conditions satisfying the resonance case, some new existence results are obtained by supposing some conditions to the nonlinear term and applying a priori estimates. 展开更多
关键词 boundary value problem RESONANCE coincidence degree theory
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Existence Results of Third Order Multi-Point Boundary Value Problem at Resonance 被引量:3
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作者 杜增吉 白占兵 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期449-452,共4页
A kind of third order multi-point boundary value problems, x'''( ι) = f( t, x ( t ), x" ( t ), x''' ( t ) ) + m 2 e(t),t∈(0, 1),x(0)=ax(ξ),x'(0)-0,x(l)= ^m2∑j=1 βjx(ηj), fεC[0,... A kind of third order multi-point boundary value problems, x'''( ι) = f( t, x ( t ), x" ( t ), x''' ( t ) ) + m 2 e(t),t∈(0, 1),x(0)=ax(ξ),x'(0)-0,x(l)= ^m2∑j=1 βjx(ηj), fεC[0, 1]×R^3, e(t)∈L^1[0, 1],a≥0, is considered, all theβj's have not the same sign, 0〈ξ〈 l, 0〈η1〈 η2〈… 〈ηm.2〈 1. By using the coincidence degree theory, some existence theorems for the problems at resonance are obtained. 展开更多
关键词 multi-point boundary value problem RESONANCE coincidence degree theory
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BOUNDARY VALUE PROBLEM FOR A GENERALIZED LINARD EQUATION 被引量:2
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作者 LiuBing YuJianshe 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期31-38,共8页
By coincidence degree,the existence of solution to the boundary value problem of a generalized Liénard equationa(t)x'+F(x,x′)x′+g(x)=e(t), x(0)=x(2π),x′(0)=x′(2π)is proved,where a∈C 1[0,2π],a(t)>... By coincidence degree,the existence of solution to the boundary value problem of a generalized Liénard equationa(t)x'+F(x,x′)x′+g(x)=e(t), x(0)=x(2π),x′(0)=x′(2π)is proved,where a∈C 1[0,2π],a(t)>0(0≤t≤2π),a(0)=a(2π),F(x,y)=f(x)+α|y| β,α>0,β>0 are all constants,f∈C(R,R),e∈C[0,2π]. An example is given as an application. 展开更多
关键词 coincidence degree boundary value problem generalized Liénard equation existence.
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SOLUTIONS TO A SECOND-ORDER MULTI-POINT BOUNDARY VALUE PROBLEM AT RESONANCE 被引量:2
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作者 杜增吉 孟凡超 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1567-1576,共10页
This article deals with the following second-order multi-point boundary value problem x″(t)=r(t,x(t),x′(t))+e(t),t∈(0,1)x′(0)=m∑i=1aix′(ξi),x(1)=n∑j=1βjx(ηj), Under the resonance conditi... This article deals with the following second-order multi-point boundary value problem x″(t)=r(t,x(t),x′(t))+e(t),t∈(0,1)x′(0)=m∑i=1aix′(ξi),x(1)=n∑j=1βjx(ηj), Under the resonance conditions m∑i=1ai=1,n∑j=1βj=1,n∑j=1βjηj=1 , by applying the coincidence degree theory, some existence results of the problem are established. The emphasis here is that the dimension of the linear operator is two. In this paper, we extend and improve some previously known results like the ones in the references. 展开更多
关键词 coincidence degree multi-point boundary value problem RESONANCE
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Permanence and periodic solutions of delayed predator-prey system with impulse 被引量:1
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作者 SHI Hong-bo 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期264-276,共13页
The existence of positive periodic solution of a generalized semi-ratio-dependent predator-prey system with time delay and impulse is studied by using the continuation theorem based on the coincidence degree theory. T... The existence of positive periodic solution of a generalized semi-ratio-dependent predator-prey system with time delay and impulse is studied by using the continuation theorem based on the coincidence degree theory. The permanence of the system is also considered. The results partially improve and extend some known criteria. 展开更多
关键词 Predator-prey system IMPULSE periodic solution PERMANENCE coincidence degree.
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ON THE ASYMPTOTIC BEHAVIOR OF HOPFIELD NEURAL NETWORK WITH PERIODIC INPUTS 被引量:1
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作者 向兰 周进 +1 位作者 刘曾荣 孙姝 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1367-1373,共7页
Without assuming the boundedness and differentiability of the nonlinear activation functions, the new sufficient conditions of the existence and the global exponential stability of periodic solutions for Hopfield neur... Without assuming the boundedness and differentiability of the nonlinear activation functions, the new sufficient conditions of the existence and the global exponential stability of periodic solutions for Hopfield neural network with periodic inputs are given by using Mawhin's coincidence degree theory and Liapunov's function method. 展开更多
关键词 Hopfield neural network periodic solution global exponential stability coincidence degree Liapunov's function
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PERIODIC SOLUTIONS OF THIRD-ORDER FUNCTIONAL DIFFERENTIAL EQUATIONS WITH VARIABLE COEFFICIENTS 被引量:2
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作者 Zhang Zhengqiu Wang ZhichengDept.ofAppl.Math.,HunanUniv.,Changsha410082,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期145-154,共10页
The sufficient condition for the existence of2 π- periodic solutions of the following third- order functional differential equations with variable coefficients a(t) x (t) +bx″2 k- 1(t) +cx′2 k- 1(t) + 2 k- 1 i=1... The sufficient condition for the existence of2 π- periodic solutions of the following third- order functional differential equations with variable coefficients a(t) x (t) +bx″2 k- 1(t) +cx′2 k- 1(t) + 2 k- 1 i=1 cixi(t) +g(x(t-τ) ) =p(t) =p(t+2π) is obtained.The approach is based on the abstract continuation theorem from Mawhin and the a- priori estimate of periodic solutions 展开更多
关键词 periodic solution abstract continuation theorem a- priori estimate coincidence degree functional differential equation
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Existence of Four Periodic Solutions of a Ratio-Dependent Predator-Prey Model with Exploited Terms 被引量:1
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作者 TIAN Desheng ZHANG Zhengqiu 《Wuhan University Journal of Natural Sciences》 CAS 2008年第1期1-5,共5页
We study a non-autonomous ratio-dependent predator-prey model with exploited terms. This model is of periodic coefficients, which incorporates the periodicity of the varying environment. By means of the coincidence de... We study a non-autonomous ratio-dependent predator-prey model with exploited terms. This model is of periodic coefficients, which incorporates the periodicity of the varying environment. By means of the coincidence degree theory, we establish sufficient conditions for the existence of at least four positive periodic solutions of this model. 展开更多
关键词 predator-prey model RATIO-DEPENDENT exploited term periodic solution coincidence degree
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PERIODICITY IN A DELAYED SEMI-RATIO-DEPENDENT PREDATOR-PREY SYSTEM 被引量:1
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作者 DingXiaoquan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第2期151-158,共8页
A delayed semi-ratio-dependent predator-prey system in a periodic environment is investigated in this paper.By using a continuation theorem based on Gaines and Mawhin's coincidence degree,the global existence of p... A delayed semi-ratio-dependent predator-prey system in a periodic environment is investigated in this paper.By using a continuation theorem based on Gaines and Mawhin's coincidence degree,the global existence of positive periodic solution is studied.A set of easily verifiable sufficient conditions are obtained. 展开更多
关键词 semi-ratio-dependent predator-prey system periodic solution coincidence degree.
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Solvability of 2n-order m-point boundary value problem at resonance 被引量:1
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作者 江卫华 郭彦平 仇计清 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第9期1219-1226,共8页
The existence of solutions at resonance is obtained by using the an example to demonstrate our result. noncontinuous. for the 2n-order m-point boundary value problem coincidence degree theory of Mawhin. We give The ... The existence of solutions at resonance is obtained by using the an example to demonstrate our result. noncontinuous. for the 2n-order m-point boundary value problem coincidence degree theory of Mawhin. We give The interest is that the nonlinear term may be 展开更多
关键词 RESONANCE Predholm operator multi-point boundary value problem coincidence degree theory
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Positive periodic solution for a nonautonomous periodic model of population with time delays and impulses 被引量:1
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作者 ZHOU Gang SHI Bao GAI Ming-jiu ZHANG De-cun Institute of Systems Science and Mathematics, Naval Aeronautical and Astronautical University, Yantai264001, China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第1期18-24,共7页
In this paper, a nonautonomous periodic model of population with time delays and impulses, which arises in order to describe the control of a single population of cells, is studied. By the coincidence degree theory we... In this paper, a nonautonomous periodic model of population with time delays and impulses, which arises in order to describe the control of a single population of cells, is studied. By the coincidence degree theory we obtain the conditions for the existence of periodic solution of this system. 展开更多
关键词 Positive periodic solution IMPULSE coincidence degree time delay.
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Existence of Solutions for Infinity-Point Nonlinear Fractional Boundary Value Problem at Resonance 被引量:1
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作者 刘瑞娟 金冉 《Journal of Donghua University(English Edition)》 EI CAS 2015年第4期665-671,共7页
A class of the boundary value problem for fractional order nonlinear differential equation with Riemann-Liouville fractional derivative on the half line was studied. By using the coincidence degree theory due to Mawhi... A class of the boundary value problem for fractional order nonlinear differential equation with Riemann-Liouville fractional derivative on the half line was studied. By using the coincidence degree theory due to Mawhin and constructing the suitable operators,the existence theorem of at least one solution has been established. An example is given to illustrate our result. 展开更多
关键词 fractional differential equation infinity-point boundary value problem coincidence degree theorem RESONANCE half line
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Positive solutions of three-point boundary value problems 被引量:1
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作者 缪烨红 张吉慧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第6期817-823,共7页
In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in... In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in resonance cases. The proposed approach is based on the Krasnoselskii's fixed point theorem and the coincidence degree. 展开更多
关键词 three-point boundary value problems positive solution fixed point theorem coincidence degree theorem
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