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Diverse soliton solutions and dynamical analysis of the discrete coupled mKdV equation with 4×4 Lax pair
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作者 刘雪珂 闻小永 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期179-191,共13页
Under consideration in this study is the discrete coupled modified Korteweg-de Vries(mKdV)equation with 4×4 Lax pair.Firstly,through using continuous limit technique,this discrete equation can be mapped to the co... Under consideration in this study is the discrete coupled modified Korteweg-de Vries(mKdV)equation with 4×4 Lax pair.Firstly,through using continuous limit technique,this discrete equation can be mapped to the coupled KdV and mKdV equations,which may depict the development of shallow water waves,the optical soliton propagation in cubic nonlinear media and the Alfven wave in a cold collision-free plasma.Secondly,the discrete generalized(r,N-r)-fold Darboux transformation is constructed and extended to solve this discrete coupled equation with the fourth-order linear spectral problem,from which diverse exact solutions including usual multi-soliton and semi-rational soliton solutions on the vanishing background,higher-order rational soliton and mixed hyperbolic-rational soliton solutions on the non-vanishing background are derived,and the limit states of some soliton and rational soliton solutions are analyzed by the asymptotic analysis technique.Finally,the numerical simulations are used to explore the dynamical behaviors of some exact soliton solutions.These results may be helpful for understanding some physical phenomena in fields of shallow water wave,optics,and plasma physics. 展开更多
关键词 discrete coupled mKdV equation continuous limit discrete generalized(r N-r)-fold Darboux transformation multi-soliton solutions rational soliton solutions
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基于Maxwell方程和R-L分数阶导数的高频激励条件下纳米晶材料磁滞特性预测模型 被引量:1
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作者 姬俊安 赵志刚 +3 位作者 张时 杜振斌 翟志强 贾慧杰 《中国电机工程学报》 EI CSCD 北大核心 2024年第13期5431-5440,I0035,共11页
准确预测高频激励条件下纳米晶材料的磁滞特性,对电力电子变压器等高频电力设备磁性元件的优化设计具有重要意义。该文基于Maxwell方程和Riemann-Liouville(R-L)分数阶导数,建立高频激励下纳米晶材料磁滞特性预测模型。首先,根据Maxwel... 准确预测高频激励条件下纳米晶材料的磁滞特性,对电力电子变压器等高频电力设备磁性元件的优化设计具有重要意义。该文基于Maxwell方程和Riemann-Liouville(R-L)分数阶导数,建立高频激励下纳米晶材料磁滞特性预测模型。首先,根据Maxwell方程,首次推导出计及趋肤效应影响的涡流磁场强度解析式;其次,针对现有静态磁滞特性和异常效应建模方法未考虑趋肤效应影响的问题,依据R-L型分数阶导数理论,建立有效描述带材内部磁通密度分布不均时纳米晶静态磁滞特性与异常效应综合预测模型,并提出一种考虑频率效应的阻尼系数ρ和非整数阶n的解析计算方法;最后,基于磁场分离理论,建立高频激励下纳米晶材料磁滞特性预测模型。通过与纳米晶材料1K107B在高频激励下实测磁滞回线进行对比,验证该文所建预测模型的有效性。相较于经典模型,该文所建模型对磁滞回线的预测精度提升了35.8%。 展开更多
关键词 MAXWELL方程 riemann-Liouville(r-L)分数阶导数 趋肤效应 磁滞回线
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New Soliton Solutions with Compact Support for a Family of Two—Parameter Regularized Long—Wave Boussinesq Equations 被引量:1
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作者 YANZhen-Ya 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第6期641-644,共4页
Searching for special solitary wave solutions with compact support is of important significance in soliton theory. In this paper, to understand the role of nonlinear dispersion in pattern formation, a family of the re... Searching for special solitary wave solutions with compact support is of important significance in soliton theory. In this paper, to understand the role of nonlinear dispersion in pattern formation, a family of the regularized long-wave Boussinesq equations with fully nonlinear dispersion (simply called equations), ( const.), is studied. New solitary wave solutions with compact support of equations are found. In addition we find another compacton solutions of the two special cases, equation and equation. It is found that the nonlinear dispersion term in a nonlinear evolution equation is not a necessary condition of that it possesses compacton solutions. 展开更多
关键词 nonlinear evolution equation r(m n) equations compacton solution
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State-vector equation with damping and vibration analysis of laminates 被引量:2
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作者 卿光辉 徐建新 邱家俊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第2期253-259,共7页
Based on the modified mixed Hellinger-Reissner(H-R) variational principle for elastic bodies with damping, the state-vector equation with parameters is directionally derived from the principle. A new solution for th... Based on the modified mixed Hellinger-Reissner(H-R) variational principle for elastic bodies with damping, the state-vector equation with parameters is directionally derived from the principle. A new solution for the harmonic vibration of simply supported rectangular laminates with damping is proposed by using the precise integration method and Muller method. The general solutions for the free vibration of underdamping, critical damp and overdamping of composite laminates are given simply in terms of the linear damping vibration theory. The effect of viscous damping force on the vibration of composite laminates is investigated through numerical examples. The state-vector equation theory and its application areas are extended. 展开更多
关键词 laminted plates DAMPING vibration H-r variational theorem statevector equation
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Numerical stability of solution to delay differential equations under resolvent condition for Runge-Kutta methods
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作者 赵景军 刘明珠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第2期135-139,共5页
Deals with the application of Kreiss resolvent condition in the error growth analysis of numerical methods, and studies the stability of Runge Kutta method in respect of Kreiss resolvent condition with emphasis on the... Deals with the application of Kreiss resolvent condition in the error growth analysis of numerical methods, and studies the stability of Runge Kutta method in respect of Kreiss resolvent condition with emphasis on the study on the subclass of collocation methods with abscissas in [0,1] by applying the methods to the test equation U′(t)=λU(t)+μU(t-τ)τ>0 with complex constraints μ and λ, and proves under some assumptions on the R K methods that the error growth is uniformly bounded in the stability region. 展开更多
关键词 Delay differential equations STABILITY Kreiss resolvent r K methods
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New Compacton Solutions of Nonlinearly Dispersive R(m, n) Equations
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作者 Mustafa Inc 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期389-394,共6页
In this paper, we establish exact solutions for the .R(m,n) equations by using an sn-cn metnou,As a result, abundant new cornpactons, i,e, solitons with the absence of infinite wings, new type of Jacobi elliptic fun... In this paper, we establish exact solutions for the .R(m,n) equations by using an sn-cn metnou,As a result, abundant new cornpactons, i,e, solitons with the absence of infinite wings, new type of Jacobi elliptic function, solitary wave and periodic wave solutions, of this equation are obtained with minimal calculations. The properties of the R(m, n) equations are shown in figures. 展开更多
关键词 r(m n) equation compacton solution SOLITON
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Periodic Solutions in UMD Spaces for Some Neutral Partial Functional Differential Equations 被引量:1
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作者 Rachid Bahloul Khalil Ezzinbi Omar Sidki 《Advances in Pure Mathematics》 2016年第10期713-726,共15页
The aim of this work is to study the existence of a periodic solution for some neutral partial functional differential equations. Our approach is based on the R-boundedness of linear operators Lp-multipliers and UMD-s... The aim of this work is to study the existence of a periodic solution for some neutral partial functional differential equations. Our approach is based on the R-boundedness of linear operators Lp-multipliers and UMD-spaces. 展开更多
关键词 Neutral Partial Functional Differential equations Periodic Solutions r-BOUNDEDNESS Lp-Multipliers UMD Spaces
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Random Crank-Nicolson Scheme for Random Heat Equation in Mean Square Sense 被引量:1
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作者 M. T. Yassen M. A. Sohaly Islam Elbaz 《American Journal of Computational Mathematics》 2016年第2期66-73,共8页
The goal of computational science is to develop models that predict phenomena observed in nature. However, these models are often based on parameters that are uncertain. In recent decades, main numerical methods for s... The goal of computational science is to develop models that predict phenomena observed in nature. However, these models are often based on parameters that are uncertain. In recent decades, main numerical methods for solving SPDEs have been used such as, finite difference and finite element schemes [1]-[5]. Also, some practical techniques like the method of lines for boundary value problems have been applied to the linear stochastic partial differential equations, and the outcomes of these approaches have been experimented numerically [7]. In [8]-[10], the author discussed mean square convergent finite difference method for solving some random partial differential equations. Random numerical techniques for both ordinary and partial random differential equations are treated in [4] [10]. As regards applications using explicit analytic solutions or numerical methods, a few results may be found in [5] [6] [11]. This article focuses on solving random heat equation by using Crank-Nicol- son technique under mean square sense and it is organized as follows. In Section 2, the mean square calculus preliminaries that will be required throughout the paper are presented. In Section 3, the Crank-Nicolson scheme for solving the random heat equation is presented. In Section 4, some case studies are showed. Short conclusions are cleared in the end section. 展开更多
关键词 random Partial Differential equations (rPDEs) Mean Square Sense (m.s) Second Order random Variable (2r.v.'s) random Crank-Nicolson Scheme CONVErGENCE CONSISTENCY Stability
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An explicit solution to the matrix equation AV+BW=EVJ
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作者 Aiguo WU Guangren DUAN Bin ZHOU 《控制理论与应用(英文版)》 EI 2007年第1期47-52,共6页
In this note, the matrix equation AV + BW = EVJ is considered, where E, A and B are given matrices of appropriate dimensions, J is an arbitrarily given Jordan matrix, V and W are the matrices to be determined. Firstl... In this note, the matrix equation AV + BW = EVJ is considered, where E, A and B are given matrices of appropriate dimensions, J is an arbitrarily given Jordan matrix, V and W are the matrices to be determined. Firstly, a right factorization of (sE - A)^-1 B is given based on the Leverriver algorithm for descriptor systems. Then based on this factorization and a proposed parametric solution, an alternative parametric solution to this matrix equation is established in terms of the R-controllability matrix of (E, A, B), the generalized symmetric operator and the observability matrix associated with the Jordan matrix d and a free parameter matrix. The proposed results provide great convenience for many analysis and design problems. Moreover, some equivalent forms are proposed. A numerical example is employed to illustrate the effect of the proposed approach. 展开更多
关键词 Generalized Sylvester matrix equations Parametric solution r-controllability Leverriver algorithm
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Lie Symmetries of Klein-Gordon and Schrodinger Equations
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作者 Muhammad Iqbal Yufeng Zhang 《Applied Mathematics》 2018年第3期336-346,共11页
In this paper, we investigate the Lie point symmetries of Klein-Gordon equation and Schr?dinger equation by applying the geometric concept of Noether point symmetries for the below defined Lagrangian. Moreover, we org... In this paper, we investigate the Lie point symmetries of Klein-Gordon equation and Schr?dinger equation by applying the geometric concept of Noether point symmetries for the below defined Lagrangian. Moreover, we organize a strong relationship among the Lie symmetries related to Klein-Gordon as well as Schr?dinger equations. Finally, we utilize the consequences of Lie point symmetries of Poisson and heat equations within Riemannian space to conclude the Lie point symmetries of Klein-Gordon equation and Schr?dinger equation within universal Riemannian space. 展开更多
关键词 Lie symmetries of Klein-Gordon equation Lie Symmetries of Schrodinger equation Noether Point Symmetries Of Conformal Lagrangian sl(2 r)Algebra Oscillator System
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Application of <i>q</i>-Calculus to the Solution of Partial <i>q</i>-Differential Equations
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作者 Maliki Olaniyi Sadik Bassey Okpo Orie 《Applied Mathematics》 2021年第8期669-678,共10页
We introduce the concept of <i>q</i>-calculus in quantum geometry. This involves the <i>q</i>-differential and <i>q</i>-integral operators. With these, we study the basic rules gove... We introduce the concept of <i>q</i>-calculus in quantum geometry. This involves the <i>q</i>-differential and <i>q</i>-integral operators. With these, we study the basic rules governing <i>q</i>-calculus as compared with the classical Newton-Leibnitz calculus, and obtain some important results. We introduce the reduced <i>q</i>-differential transform method (R<i>q</i>DTM) for solving partial <i>q</i>-differential equations. The solution is computed in the form of a convergent power series with easily computable coefficients. With the help of some test examples, we discover the effectiveness and performance of the proposed method and employing MathCAD 14 software for computation. It turns out that when <i>q</i> = 1, the solution coincides with that for the classical version of the given initial value problem. The results demonstrate that the R<i>q</i>DTM approach is quite efficient and convenient. 展开更多
关键词 q-Differential q-Integral Operators rqDTM Method Initial Value Problem Partial Differential equation MathCAD 14
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S-asymptotically ω-periodic Solutions of R-L Fractional Derivative-Integral Equation
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作者 WANG Bing 《科技视界》 2015年第17期155-155,245,共2页
The aim of this paper is to study the S-asymptotically ω-periodic solutions of R-L fractional derivative-integral equation:v′(t)=∫t0(t-s)α-2/Γ(α-1)Av(s)ds+∫+∞-∞e-|τ|f(u(t-τ))dτ,(1)v(0)=u0∈X,(2)where 1 <... The aim of this paper is to study the S-asymptotically ω-periodic solutions of R-L fractional derivative-integral equation:v′(t)=∫t0(t-s)α-2/Γ(α-1)Av(s)ds+∫+∞-∞e-|τ|f(u(t-τ))dτ,(1)v(0)=u0∈X,(2)where 1 <α <2, A:D(A)X→X is a linear densely defined operator of sectorial type on a completed Banach space X, f is a continuous function satisfying a suitable Lipschitz type condition. We will use the contraction mapping theory to prove problem(1) and(2) has a unique S-asymptoticallyω-periodic solution if the function f satisfies Lipshcitz condition. 展开更多
关键词 微分方程 周期解 压缩映射原理 数学理论
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尖头塘鳢(Eleotris oxycephala)雌雄个体形态差异分析 被引量:1
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作者 陈宇舒 《渔业研究》 2023年第4期346-355,共10页
为探究尖头塘鳢(Eleotris oxycephala)雌雄个体形态学差异,提高其性别选育效率,本文运用了主成分分析、R-聚类分析、逐步判别分析和T检验分析等方法,对60尾、体质量为18.7~55.1 g的野生尖头塘鳢的17个直接测量性状和14个标准化性状进行... 为探究尖头塘鳢(Eleotris oxycephala)雌雄个体形态学差异,提高其性别选育效率,本文运用了主成分分析、R-聚类分析、逐步判别分析和T检验分析等方法,对60尾、体质量为18.7~55.1 g的野生尖头塘鳢的17个直接测量性状和14个标准化性状进行分析。T检验分析结果显示,尖头塘鳢雌雄个体之间体型大小差异显著,雄性个体体型较雌性个体大;而尖头塘鳢雌雄个体间丰满度差异较小。通过主成分分析、R-聚类分析和逐步判别分析筛选出尖头塘鳢雌雄群体间具有显著差异的性状,建立雌雄个体判别模型,雄:F 1=-63.908 X_(1)+626.425 X_(2)+2298.275 X_(3)+173.546 X_(4)-55.640 X_(5)-239.618,雌:F 2=68.365 X_(1)+510.204 X_(2)+1936.135 X_(3)+150.444 X_(4)+48.164 X_(5)-204.308,经回判验证可知,雌雄个体综合判别准确率为98.3%。将另一流域采集的23尾野生尖头塘鳢的形态性状数据带入判别模型进行验证,结果显示,综合判别准确率为82.6%。 展开更多
关键词 尖头塘鳢 形态学差异 主成分分析 逐步判别分析 r-聚类分析 雌雄个体判别模型
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40种乔木8种灌木燃烧性的R-Ⅲ方程计算与分类 被引量:15
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作者 张景群 王得祥 《林业科学》 EI CAS CSCD 北大核心 1999年第4期51-57,共7页
应用包含发热量、含水率、燃点和水分蒸发力4个因子的RⅢ方程,对40种乔木,8种灌木鲜可燃物完全燃烧的净放热量进行计算并分类表明,燃烧性强(净放热量>5822kJ)的植物有16种,燃烧性中等(净放热量为3590~58... 应用包含发热量、含水率、燃点和水分蒸发力4个因子的RⅢ方程,对40种乔木,8种灌木鲜可燃物完全燃烧的净放热量进行计算并分类表明,燃烧性强(净放热量>5822kJ)的植物有16种,燃烧性中等(净放热量为3590~5822kJ)的有19种,燃烧性差(净放热量>3590kJ的有13种。燃烧性差的植物是山杨(P.davidiana),青榨槭(A.davidi)、光皮桦(B.luminfera)、青(P.wilsoni)、漆树(R.verniciflua)、旱柳(S.matsudana)、化香(P.strobilacea)、毛白杨(P.tomentosa)、山楂(C.prinnatifida)、山桐子(I.polycarpa)、核桃(J.regia)、白玉兰(M.denudata)、女贞(L.lucidum),以上树种可作为防火林带的备选树种。 展开更多
关键词 乔木 灌木 燃烧性 r-Ⅲ方程 分类
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P-R方程在天然气热物性计算中的应用 被引量:11
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作者 洪丽娜 陈保东 +5 位作者 李庆杰 韩莉 顾福昕 王洋 仲权伟 张宏宇 《辽宁石油化工大学学报》 CAS 2008年第2期48-52,共5页
在天然气管道的水力、热力计算中需要进行热物性参数的计算,详细地介绍了用P-R方程求解天然气各物性参数的方法及其求解过程。分别采用范德瓦尔斯方程、RKS方程、P-R方程和BWRS方程求氮气的压缩因子,通过与已知实验数据比较表明P-R方程... 在天然气管道的水力、热力计算中需要进行热物性参数的计算,详细地介绍了用P-R方程求解天然气各物性参数的方法及其求解过程。分别采用范德瓦尔斯方程、RKS方程、P-R方程和BWRS方程求氮气的压缩因子,通过与已知实验数据比较表明P-R方程作为两参数立方型方程,计算气体物性参数精度高于范德瓦尔斯方程和RKS方程,略低于BWRS方程。P-R方程参数数目少,参数确定简洁,计算简单,可以在天然气物性计算领域广泛应用。 展开更多
关键词 天然气 P-r方程 应用
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P-R方程在天然气热物性计算中的应用 被引量:17
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作者 唐迎春 陈保东 +1 位作者 王凯 刘文启 《石油化工高等学校学报》 EI CAS 2005年第2期47-49,71,共4页
西气东输工程是目前我国距离最长、输量最大、设计压力最高的长输天然气管道。为了合理的生产和输送,实现有效的调度和管理,有必要对输气管进行工况模拟。工况模拟中天然气的热物理性质参数是首先需要求得的参数。在输气管高达10MPa的... 西气东输工程是目前我国距离最长、输量最大、设计压力最高的长输天然气管道。为了合理的生产和输送,实现有效的调度和管理,有必要对输气管进行工况模拟。工况模拟中天然气的热物理性质参数是首先需要求得的参数。在输气管高达10MPa的高压下,天然气的热物性若用理想气体状态方程进行分析计算,将会产生很大的误差。采用实际状态方程P -R方程,分析和计算输气管工艺计算中的热物性参数,常数确定简洁,能很好的满足工程计算精度和工艺要求。 展开更多
关键词 输气管道 模拟 热物理性质 P—r方程
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企业规模与R&D投入强度关系的实证分析 被引量:91
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作者 柴俊武 万迪昉 《科学学研究》 CSSCI 北大核心 2003年第1期58-62,共5页
以西安市近八百家企业为研究对象 ,应用结构方程模型 ,对企业规模与企业R&D投入强度的关系进行了实证分析 ,结果表明 :企业规模与企业R&D投入强度呈倒U型曲线关系 ,当企业规模较小时 ,与企业R&D投入强度正相关 ;当企业规模... 以西安市近八百家企业为研究对象 ,应用结构方程模型 ,对企业规模与企业R&D投入强度的关系进行了实证分析 ,结果表明 :企业规模与企业R&D投入强度呈倒U型曲线关系 ,当企业规模较小时 ,与企业R&D投入强度正相关 ;当企业规模较大时 ,与企业R&D投入强度负相关。实证分析结果显示 :企业被评为高新技术企业对R&D投入强度有正面的影响 ;企业经营者才能有助于增加企业进入高新技术行列的可能性 ,并进而促进R&D投入强度的增大。 展开更多
关键词 企业规模 r&D投入强度 结构方程模型
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R-函数理论在梯形截面柱弹性扭转问题中的应用 被引量:8
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作者 王红 袁鸿 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第11期99-101,共3页
将弹性扭转问题看成为泊松方程的边值问题,利用泊松方程的基本解构造了一个函数,推导出第二类Fredholm积分方程.应用R-函数理论,构建了一个规范化方程.通过寻找适当的规范化方程,来表示问题的边界,并证明积分方程核的奇异性被克服了.通... 将弹性扭转问题看成为泊松方程的边值问题,利用泊松方程的基本解构造了一个函数,推导出第二类Fredholm积分方程.应用R-函数理论,构建了一个规范化方程.通过寻找适当的规范化方程,来表示问题的边界,并证明积分方程核的奇异性被克服了.通过研究梯形截面弹性体的扭转问题,表明结果与有限元数值计算结果很接近,该方法具有较高的精度,为边值问题的研究和求解提供了一种新的数学方法.该方法同样可以解决位势问题,还可以用来讨论其他更为复杂的算子,并且适用于其他形状的情形. 展开更多
关键词 r-函数理论 规范化方程 泊松方程 FrEDHOLM积分方程 扭转
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非线性Sobolev-Galpern方程的有限维整体吸引子(英文) 被引量:10
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作者 尚亚东 房少梅 《应用数学》 CSCD 北大核心 2003年第4期122-129,共8页
本文研究非线性Sobolev Galpern方程解的渐近性态 .首先证明了该方程在H2 (Ω)∩H1 0 (Ω)中整体弱吸引子的存在性 ,然后利用一个能量方程证明了整体弱吸引子实际上是整体强吸引子 .
关键词 非线性SOBOLEV-GALPErN方程 整体吸引子 渐近性 能量方程 弱收敛性 有限维性 初边值问题
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企业R&D投入、技术能力与绩效关系——基于浙江企业的实证研究 被引量:8
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作者 程华 邵波 徐阿进 《科学管理研究》 CSSCI 北大核心 2012年第5期109-112,共4页
基于相关文献研究,提出了企业R&D投入、技术能力与绩效三者之间的关系理论假设模型。通过调查问卷获得数据,采用结构方程模型分析发现:技术能力在R&D投入与绩效之间起到完全中介作用。进一步对技术能力中的4个维度:人员能力、... 基于相关文献研究,提出了企业R&D投入、技术能力与绩效三者之间的关系理论假设模型。通过调查问卷获得数据,采用结构方程模型分析发现:技术能力在R&D投入与绩效之间起到完全中介作用。进一步对技术能力中的4个维度:人员能力、设备能力、信息能力和组织能力进行分析,发现只有设备能力在R&D投入与绩效之间存在中介效应。 展开更多
关键词 r&D投入 技术能力 绩效 结构方程模型
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