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测度链上非线性微分方程的三正解(英文) 被引量:1
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作者 柏传志 《数学杂志》 CSCD 北大核心 2004年第4期361-364,共4页
运用文 [1 ]中的Leggett Williams不动点定理 ,我们给出了测度链上的非线性微分方程-xΔΔ(t) =f(t,x(σ(t) ) ) ,t∈ [a,b]关于两点边值条件αx(a) - βxΔ(a) =0 ,γx(σ(b) ) +δxΔ(σ(b) )
关键词 边界值问题 测度链 三正解 Leggett—Williams不动点定理
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带有积分边值条件的分数阶微分方程正解的存在性 被引量:4
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作者 刘晓娟 魏永芳 白占兵 《山东科技大学学报(自然科学版)》 CAS 北大核心 2019年第2期100-105,共6页
运用推广的Leggett-Williams不动点定理,得到了带有积分边值条件的分数阶微分方程的三正解的存在性结果,并通过例子验证给出结果的有效性。
关键词 不动点定理 分数阶微分方程 三正解
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Application of 3D AVO Interpretation Technique to Lithological Reservoir in the Hongze Area
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作者 谢占安 《Applied Geophysics》 SCIE CSCD 2005年第3期168-174,F0003,共8页
In the Hongze Area, the reservoirs vary rapidly laterally and are controlled by many factors, such as structure, lithology, oil source, and so on. S-wave well log curves are calculated from an equation derived from mu... In the Hongze Area, the reservoirs vary rapidly laterally and are controlled by many factors, such as structure, lithology, oil source, and so on. S-wave well log curves are calculated from an equation derived from multiple-attribute regression analysis of RT, DT, GR, and DEN logs. Representative P-and S-wave velocities and Poisson's ratio are statistically computed for oil and water bearing reservoir rock, shale, and calcareous shale in each well. The averaged values are used for AVO forward modeling. Comparing the modeling results with actual seismic data limit the possible AVO interpretations. Well and seismic data are used to calibrate inverted P-wave, S-wave, Poisson's ratio, and AVO gradient attribute data sets. AVO gradient data is used for lithofacies interpretation, P-wave data is used for acoustic impedance inversion, S-wave data is used for elastic impedance, and Poisson's ratio data is used for detecting oil and gas. The reservoir and hydrocarbon detections are carried out sequentially. We demonstrate that the AVO attributes method can efficiently predict reservoir and hydrocarbon potential. 展开更多
关键词 S-WAVE Poisson's ratio GRADIENT modeling attribute calibration
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Existence of Multiple Positive Solutions on the Three Point Boundary Value Problems 被引量:1
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作者 任立顺 王治国 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期406-411,共6页
In this paper, using fixed theorem in cones, the authors obtain the existence of multiple positive solutions on the following boundary value problem u"+a(t)f(u)=0,t∈[0,1],u(0)=0,au(η)^*=u(1).
关键词 second order three point BUP positive solution cone EXISTENCE
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Direct linear discriminant analysis based on column pivoting QR decomposition and economic SVD
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作者 胡长晖 路小波 +1 位作者 杜一君 陈伍军 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期395-399,共5页
A direct linear discriminant analysis algorithm based on economic singular value decomposition (DLDA/ESVD) is proposed to address the computationally complex problem of the conventional DLDA algorithm, which directl... A direct linear discriminant analysis algorithm based on economic singular value decomposition (DLDA/ESVD) is proposed to address the computationally complex problem of the conventional DLDA algorithm, which directly uses ESVD to reduce dimension and extract eigenvectors corresponding to nonzero eigenvalues. Then a DLDA algorithm based on column pivoting orthogonal triangular (QR) decomposition and ESVD (DLDA/QR-ESVD) is proposed to improve the performance of the DLDA/ESVD algorithm by processing a high-dimensional low rank matrix, which uses column pivoting QR decomposition to reduce dimension and ESVD to extract eigenvectors corresponding to nonzero eigenvalues. The experimental results on ORL, FERET and YALE face databases show that the proposed two algorithms can achieve almost the same performance and outperform the conventional DLDA algorithm in terms of computational complexity and training time. In addition, the experimental results on random data matrices show that the DLDA/QR-ESVD algorithm achieves better performance than the DLDA/ESVD algorithm by processing high-dimensional low rank matrices. 展开更多
关键词 direct linear discriminant analysis column pivoting orthogonal triangular decomposition economic singular value decomposition dimension reduction feature extraction
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Multiple Positive Solutions to a Nonlinear Two-point Boundary Value Problem with p-Laplacian 被引量:4
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作者 李志艳 严树林 葛渭高 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2006年第3期480-488,共9页
By a simple application of a new three functionals fixed point theorem, sufficient conditions axe obtained to guarantee the existence of at least three positive solutions for p-Laplacian equation: (φp(u′))′ +... By a simple application of a new three functionals fixed point theorem, sufficient conditions axe obtained to guarantee the existence of at least three positive solutions for p-Laplacian equation: (φp(u′))′ + α(t)f(t,u(t)) = 0 subject to nonlinear boundary value conditions. An example is presented to illustrate the theory. 展开更多
关键词 boundary value problem p-Laplacian operator positive solution the threefunctionals fixed point theorem.
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Existence of Positive Solutions for a Third-Order Three-Point Boundary Value Problem with Semipositone Nonlinearity * 被引量:5
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作者 姚庆六 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第4期591-596,共6页
The existence of positive solutions is investigated for following semipositone nonlinear third-order three-point BVP ω''(t) - λf(t,w(t)) = 0, 0 ≤ t ≤ 1, ω(0) = ω'(n) = ω'(1) = 0.
关键词 third-order semipositone ODE three-point BVP existence ot positive solution fixed point theorem on cone.
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Positive Solutions of a Three-Point Boundary Value Problem
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作者 韩晓玲 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2007年第3期497-504,共8页
We study the existence of positive solutions of the three-point boundary value problem u"+g(t)f(u)=0,t∈(0,1),u′(0)=0,u(1)=αu(η), where η∈(0, 1), and α∈R with 0 〈α〈 1. The existence of posit... We study the existence of positive solutions of the three-point boundary value problem u"+g(t)f(u)=0,t∈(0,1),u′(0)=0,u(1)=αu(η), where η∈(0, 1), and α∈R with 0 〈α〈 1. The existence of positive solutions is studied by means of fixed point index theory under some conditions concerning the first eigenvalue with respect to the relevant linear operator. The results, here essentially extend and improve the main result in [1]. 展开更多
关键词 three-point boundary value problem positive solution CONE fixed point index.
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The Existence of Three Positive Solutions for a Class of Nonlinear Three-Point Boundary Value Problem with p-Laplacian 被引量:2
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作者 LI Xiang Feng XU Hong Wu 《Journal of Mathematical Research and Exposition》 CSCD 2009年第3期507-516,共10页
This paper deals with the existence of three positive solutions for a class of nonlinear singular three-point boundary value problem with p-Laplacian. By means of a fixed point theorem duo to Leggett and Williams, suf... This paper deals with the existence of three positive solutions for a class of nonlinear singular three-point boundary value problem with p-Laplacian. By means of a fixed point theorem duo to Leggett and Williams, sufficient condition for the existence of at least three positive solutions to the nonlinear singular three-point boundary value problem is established 展开更多
关键词 p-Laplacian operator positive solution three-point singular boundary value problem fixed-point theorem
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Selectively constructing sandwich-like heterostructure of CdS/PbTiO_(3)/TiO_(2)to improve visible-light photocatalytic H_(2)evolution 被引量:5
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作者 Gedeng Wan Yongqiang Yang +4 位作者 Huaze Zhu Chao Zhen Xiaoxiang Xu Lianzhou Wang Gang Liu 《Science China Materials》 SCIE EI CAS CSCD 2022年第12期3428-3434,共7页
Fast migration and efficient spatial separation of photogenerated charges in photocatalytic materials are indispensable to efficient solar water splitting reactions.Here,we construct a three-phase heterostructure of C... Fast migration and efficient spatial separation of photogenerated charges in photocatalytic materials are indispensable to efficient solar water splitting reactions.Here,we construct a three-phase heterostructure of CdS/PbTiO_(3)/TiO_(2)by selectively depositing CdS and TiO_(2)at oppositely poled crystal facets of PbTiO_(3)using single-domain ferroelectric PbTiO_(3).The heterostructure has matching band edge alignments and strong interfacial connections at different moieties.The heterostructure combines the interfacial electrical and ferroelectric fields because of their peculiar microstructures,which provide a strong driving force throughout the whole bulk to separate photogenerated charges.Almost two orders of magnitude improvement of visible-light-driven photocatalytic H_(2) production has been realized in CdS/PbTiO_(3)/TiO_(2)compared with bare PbTiO_(3)/TiO_(2),showing the efficiency of charge separation in the heterostructure.The idea of combining ferroelectrics with potential light capture semiconductor provides a paradigm to accurately design charge migration pathways,bringing a step closer to efficient solar water splitting. 展开更多
关键词 photocatalysis FERROELECTRIC PBTIO3 water splitting HETEROSTRUCTURE
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