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流体力学中一个广义函数方程解析解的存在性
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作者 贾文敬 《中国矿业大学学报》 EI CAS CSCD 北大核心 2003年第4期466-470,共5页
给出了方程φ~2+gφ~2=h(g,h是给定的关于z的有理函数)解析解存在的充分必要条件,同时利用构造性方法给出所有满足此方程解析解的一般结构形式: φ=(d^(-1)qq_1)^(1/2)sin((qpd)^(1/2)γ(z)) φ=(p^(-1)q_1g_2)^(1/2)cos((qpd)^(1/2)γ(... 给出了方程φ~2+gφ~2=h(g,h是给定的关于z的有理函数)解析解存在的充分必要条件,同时利用构造性方法给出所有满足此方程解析解的一般结构形式: φ=(d^(-1)qq_1)^(1/2)sin((qpd)^(1/2)γ(z)) φ=(p^(-1)q_1g_2)^(1/2)cos((qpd)^(1/2)γ(z))是流体力学中研究硬性球状颗粒混合物的Percus-Yevick方程时推导出的函数方程的广义形式。 展开更多
关键词 流体力学 广义函数方程 解析解 存在性 硬性球状颗粒混合物 函数 零点
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两类广义对数函数方程和Pexider推广(英文)
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作者 刘晓华 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第3期359-363,共5页
函数方程在数学、空气动力学和动态经济学等领域都被涉及,因此函数方程的研究对科学技术的发展和国民经济建设都有重要的作用.众所周知的对数函数方程在实践中具有广泛的应用,近年来,它引起了研究者的关注.在这篇文章中,我们证明了两类... 函数方程在数学、空气动力学和动态经济学等领域都被涉及,因此函数方程的研究对科学技术的发展和国民经济建设都有重要的作用.众所周知的对数函数方程在实践中具有广泛的应用,近年来,它引起了研究者的关注.在这篇文章中,我们证明了两类广义对数函数方程与古典对数函数方程等效.对其中一类广义对数函数方程,我们讨论了它的Pexider方程,并给出了它的通解.对另一类广义对数函数方程,我们也讨论了它的Pexider方程,并给出了它的二次可微解,从而推广了文献(K.J.Heuvers,P.Kannappan.Aequationes Math,2005,70:117-121.)和(K.J.Heuvers.Aequationes Math,1999,58:260-264.)的相关结果. 展开更多
关键词 广义对数函数方程 古典对数函数方程 Pexider方程
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关于广义Pexider方程解的注记
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作者 刘晓华 《乐山师范学院学报》 2013年第5期13-15,32,共4页
许多领域的研究离不开函数方程,特别在动力系统和嵌入流中十分重要,函数方程有各种形式,对他们的求解是复杂的,有时甚至是相当困难的。文章首先研究了两类广义Pexider函数方程,对其中一类我们用换元法将其转化为已有的Pexider对数方程,... 许多领域的研究离不开函数方程,特别在动力系统和嵌入流中十分重要,函数方程有各种形式,对他们的求解是复杂的,有时甚至是相当困难的。文章首先研究了两类广义Pexider函数方程,对其中一类我们用换元法将其转化为已有的Pexider对数方程,从而求得其一般解,对另一类我们采用将方程两端先微分使其转化为微分方程,然后求解微分方程,从而获得了它的二次可微解. 展开更多
关键词 广义Pexider函数方程 一般解 二次可微解
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The generalized Chapman-Richards function and applications to tree and stand growth 被引量:10
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作者 刘兆刚 李凤日 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期19-26,共8页
The generalized Chapman-Richards model was derived from the Chapman-Richards function in which parameters h, k and m were unconstrained. Based on the structure of solutions and biological interpretations, the model co... The generalized Chapman-Richards model was derived from the Chapman-Richards function in which parameters h, k and m were unconstrained. Based on the structure of solutions and biological interpretations, the model could be classified into eight cases (three categories) at all and among them only 4 kinds of cases are suitable in forestry that represent four typical growth patterns of trees and stands. For each of 4 equations, the model properties and biological interpretations for parameters were discussed in detail. The generalized Chapman-Richards model was capable of describing a wide range of growth curves that was asymptotic or nonasymptotic, with or without inflection point. In order to illustrate the versatility of the model, it was fitted to a group of data sets concerning the DBH growth of cryptomeria plantations with 4 initial densities and the DBH and height growth of natural Korean pine tree. Comparing the generalized Chapman-Richards function and the Schnute model, it was found that the parameters and expressions of the two models were interchangeable in theory, and the fitting results were explicitly identical in empirical applications. 展开更多
关键词 Generalized Chapman-Richards function Schnute model Growth model Growth pattern Cryptomeria japonica Pinus koraiensis
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Symbolic Computation and New Families of Exact Non-travelling Wave Solutions of (2+1)-dimensional Broer-Kaup Equations 被引量:1
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作者 ZHANG Sheng XIA Tie-Cheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期985-990,共6页
The improved tanh function method [Commun. Theor. Phys. (Beijing, China) 43 (2005) 585] is further improved by generalizing the ansatz solution of the considered equation. As its application, the (2+1)-dimensio... The improved tanh function method [Commun. Theor. Phys. (Beijing, China) 43 (2005) 585] is further improved by generalizing the ansatz solution of the considered equation. As its application, the (2+1)-dimensional Broer-Kaup equations are considered and abundant new exact non-travelling wave solutions are obtained. 展开更多
关键词 non-travelling wave solutions improved tanh function method generalized Riccati equation
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On an Auto-Baecklund Transformation for (2+1)-Dimensional VariableCoefficient Generalized KP Equations and Exact Solutions 被引量:1
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作者 BAICheng-Jie BAICheng-Lin +1 位作者 HANJi-Guang ZHAOHong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期677-680,共4页
By the application of the extended homogeneous balance method, we derive anauto-Backlund transformation (BT) for (2+1)-dimensional variable coefficient generalized KPequations. Based on the BT, in which there are two ... By the application of the extended homogeneous balance method, we derive anauto-Backlund transformation (BT) for (2+1)-dimensional variable coefficient generalized KPequations. Based on the BT, in which there are two homogeneity equations to be solved, we obtainsome exact solutions containing single solitary waves. 展开更多
关键词 extended homogeneous balance method (2+1)-dimensional variable coefficientgeneralized KP equation auto-Baecklund transformation exact solutions
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New Multiple Soliton-like and Periodic Solutions for (2+l)-Dimensional Canonical Generalized KP Equation with Variable Coefficients 被引量:3
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作者 ZHANG Li-Hua LIU Xi-Qiang BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期793-798,共6页
In this paper, the generalized ranch function method is extended to (2+1)-dimensianal canonical generalized KP (CGKP) equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit ... In this paper, the generalized ranch function method is extended to (2+1)-dimensianal canonical generalized KP (CGKP) equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit exact solutions, which contain multiple soliton-like and periodic solutions, are obtained for the (2+1)-dimensional OGKP equation with variable coetffcients. 展开更多
关键词 (2+1)-dimensional canonical generalized (CGKP) equation with variable coefficients tanh function method Riccati equation soliton-like and periodic solutions
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Spectral Method for Three-Dimensional Nonlinear Klein-Gordon Equation by Using Generalized Laguerre and Spherical Harmonic Functions 被引量:3
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作者 Xiao-Yong Zhang Ben-Yu Guo Yu-Jian Jiao 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第1期43-64,共22页
In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve ... In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve the same conservation as that for the exact solution.The stability and convergence of the proposed scheme are proved.Numerical results demonstrate the efficiency of this approach.We also establish some basic results on the generalized Laguerre-spherical harmonic orthogonal approximation,which play an important role in spectral methods for various problems defined on the whole space and unbounded domains with spherical geometry. 展开更多
关键词 Generalized Laguerre-spherical harmonic spectral method Cauchy problem of nonlinear Klein-Gordon equation.
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New Soliton-like Solutions for (2+1)-Dimensional Breaking Soliton Equation
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作者 XIEZheng ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期401-406,共6页
The (2+1)-dimensional breaking soliton equation describes the interaction of a Riemann wave propagating along the y-axis with a long wave along the x-axis. In this paper, with the aid of symbolic computation, six kind... The (2+1)-dimensional breaking soliton equation describes the interaction of a Riemann wave propagating along the y-axis with a long wave along the x-axis. In this paper, with the aid of symbolic computation, six kinds of new special exact soltion-like solutions of (2+1)-dimensional breaking soliton equation are obtained by using some general transformations and the further generalized projective Riccati equation method. 展开更多
关键词 (2+l)-dimensional breaking soliton equation generalized projective Riccatiequation method soliton-like solution
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Traveling Wave Solutions for Generalized Bretherton Equation
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作者 Amin Esfahani 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期381-386,共6页
This paper studies the Generalized Bretherton equation using trigonometric function method including the sech-function method, the sine-cosine function method, and the tanh-function method, and He's semi-inverse meth... This paper studies the Generalized Bretherton equation using trigonometric function method including the sech-function method, the sine-cosine function method, and the tanh-function method, and He's semi-inverse method (He's variational method). Various traveling wave solutions are obtained, revealing an intrinsic relationship among the amplitude, frequency, and wave speed. 展开更多
关键词 Bretherton equation traveling wave trigonometric function method variational method
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SPECTRAL ANALYSIS AND STABILIZATION OF A COUPLED WAVE-ODE SYSTEM 被引量:1
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作者 ZHAO Dongxia WANG Junmin 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第3期463-475,共13页
In this paper, an interconnected wave-ODE system with K-V damping in the wave equation and unknown parameters in the ODE is considered. It is found that the spectrum of the system operator is composed of two parts: P... In this paper, an interconnected wave-ODE system with K-V damping in the wave equation and unknown parameters in the ODE is considered. It is found that the spectrum of the system operator is composed of two parts: Point spectrum and continuous spectrum. The continuous spectrum consists of an isolated point 1 1/d, and there are two branches of the asymptotic eigenvalues: The first branch is accumulating towards 1 -2, and the other branch tends to -∞. It is shown that there is a sequence of generalized eigenfunctions, which forms a Riesz basis for the Hilbert state space. As a consequence, the spectrum-determined growth condition and exponential stability of the system are concluded. 展开更多
关键词 Exponential stability Kelvin-Voigt damping Riesz basis SPECTRUM wave equation.
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Ramanujan's cubic transformation and generalized modular equation
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作者 WANG MiaoKun CHU YuMing SONG YingQing 《Science China Mathematics》 SCIE CSCD 2015年第11期2387-2404,共18页
We study the quotient of hypergeometric functions in the theory of Ramanujan's generalized modular equation for a ∈ (0, 1/2], and find an infinite product for- mula for μ1/3(r) by use of the properties of μ*a... We study the quotient of hypergeometric functions in the theory of Ramanujan's generalized modular equation for a ∈ (0, 1/2], and find an infinite product for- mula for μ1/3(r) by use of the properties of μ*a(r) and Ramanujan's cubic transformation. Besides, a new cubic transformation formula of hypergeometric function is given, which complements the Ramanujan's cubic transformation. 展开更多
关键词 Gaussian hypergeometric function Ramanujan's cubic transformation generalized modular equa-tion infinite product modular function
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Optimal Transportation for Generalized Lagrangian
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作者 Ji LI Jianlu ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2017年第3期857-868,共12页
This paper deals with the optimal transportation for generalized Lagrangian L = L(x, u, t), and considers the following cost function: c(x, y) = inf x(0)=x x(1)=y u∈U∫0^1 L(x(s), u(x(s), s), s)ds, w... This paper deals with the optimal transportation for generalized Lagrangian L = L(x, u, t), and considers the following cost function: c(x, y) = inf x(0)=x x(1)=y u∈U∫0^1 L(x(s), u(x(s), s), s)ds, where U is a control set, and x satisfies the ordinary equation x(s) = f(x(s), u(x(s), s)).It is proved that under the condition that the initial measure μ0 is absolutely continuous w.r.t. the Lebesgue measure, the Monge problem has a solution, and the optimal transport map just walks along the characteristic curves of the corresponding Hamilton-Jacobi equation:Vt(t, x) + sup u∈U = 0,V(0, x) = Φ0(x). 展开更多
关键词 Optimal control Hamilton-Jacobi equation Characteristic curve Viscosity solution Optimal transportation Kantorovich pair Initial transport measure
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