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Integrating Variable Reduction Strategy With Evolutionary Algorithms for Solving Nonlinear Equations Systems 被引量:1
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作者 Aijuan Song Guohua Wu +1 位作者 Witold Pedrycz Ling Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第1期75-89,共15页
Nonlinear equations systems(NESs)are widely used in real-world problems and they are difficult to solve due to their nonlinearity and multiple roots.Evolutionary algorithms(EAs)are one of the methods for solving NESs,... Nonlinear equations systems(NESs)are widely used in real-world problems and they are difficult to solve due to their nonlinearity and multiple roots.Evolutionary algorithms(EAs)are one of the methods for solving NESs,given their global search capabilities and ability to locate multiple roots of a NES simultaneously within one run.Currently,the majority of research on using EAs to solve NESs focuses on transformation techniques and improving the performance of the used EAs.By contrast,problem domain knowledge of NESs is investigated in this study,where we propose the incorporation of a variable reduction strategy(VRS)into EAs to solve NESs.The VRS makes full use of the systems of expressing a NES and uses some variables(i.e.,core variable)to represent other variables(i.e.,reduced variables)through variable relationships that exist in the equation systems.It enables the reduction of partial variables and equations and shrinks the decision space,thereby reducing the complexity of the problem and improving the search efficiency of the EAs.To test the effectiveness of VRS in dealing with NESs,this paper mainly integrates the VRS into two existing state-of-the-art EA methods(i.e.,MONES and DR-JADE)according to the integration framework of the VRS and EA,respectively.Experimental results show that,with the assistance of the VRS,the EA methods can produce better results than the original methods and other compared methods.Furthermore,extensive experiments regarding the influence of different reduction schemes and EAs substantiate that a better EA for solving a NES with more reduced variables tends to provide better performance. 展开更多
关键词 Evolutionary algorithm(EA) nonlinear equations systems(ENSs) problem domain knowledge variable reduction strategy(VRS)
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SOLVERS FOR SYSTEMS OF LARGE SPARSE LINEAR AND NONLINEAR EQUATIONS BASED ON MULTI-GPUS 被引量:3
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作者 刘沙 钟诚文 陈效鹏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第3期300-308,共9页
Numerical treatment of engineering application problems often eventually results in a solution of systems of linear or nonlinear equations.The solution process using digital computational devices usually takes tremend... Numerical treatment of engineering application problems often eventually results in a solution of systems of linear or nonlinear equations.The solution process using digital computational devices usually takes tremendous time due to the extremely large size encountered in most real-world engineering applications.So,practical solvers for systems of linear and nonlinear equations based on multi graphic process units(GPUs)are proposed in order to accelerate the solving process.In the linear and nonlinear solvers,the preconditioned bi-conjugate gradient stable(PBi-CGstab)method and the Inexact Newton method are used to achieve the fast and stable convergence behavior.Multi-GPUs are utilized to obtain more data storage that large size problems need. 展开更多
关键词 general purpose graphic process unit(GPGPU) compute unified device architecture(CUDA) system of linear equations system of nonlinear equations Inexact Newton method bi-conjugate gradient stable(Bi-CGstab)method
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Solving Nonlinear Equations Systems with an Enhanced Reinforcement Learning Based Differential Evolution 被引量:4
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作者 Zuowen Liao Shuijia Li 《Complex System Modeling and Simulation》 2022年第1期78-95,共18页
Nonlinear equations systems(NESs)arise in a wide range of domains.Solving NESs requires the algorithm to locate multiple roots simultaneously.To deal with NESs efficiently,this study presents an enhanced reinforcement... Nonlinear equations systems(NESs)arise in a wide range of domains.Solving NESs requires the algorithm to locate multiple roots simultaneously.To deal with NESs efficiently,this study presents an enhanced reinforcement learning based differential evolution with the following major characteristics:(1)the design of state function uses the information on the fitness alternation action;(2)different neighborhood sizes and mutation strategies are combined as optional actions;and(3)the unbalanced assignment method is adopted to change the reward value to select the optimal actions.To evaluate the performance of our approach,30 NESs test problems and 18 test instances with different features are selected as the test suite.The experimental results indicate that the proposed approach can improve the performance in solving NESs,and outperform several state-of-the-art methods. 展开更多
关键词 nonlinear equations systems reinforcement learning differential evolution multiple roots location
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APPROXIMATE CONTROLLABILITY OF NONLINEAR EVOLUTION FRACTIONAL CONTROL SYSTEM WITH DELAY 被引量:1
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作者 Kamla Kant MISHRA Shruti DUBEY 《Acta Mathematica Scientia》 2025年第2期553-568,共16页
This article studies the existence and uniqueness of the mild solution of a family of control systems with a delay that are governed by the nonlinear fractional evolution differential equations in Banach spaces.Moreov... This article studies the existence and uniqueness of the mild solution of a family of control systems with a delay that are governed by the nonlinear fractional evolution differential equations in Banach spaces.Moreover,we establish the controllability of the considered system.To do so,first,we investigate the approximate controllability of the corresponding linear system.Subsequently,we prove the nonlinear system is approximately controllable if the corresponding linear system is approximately controllable.To reach the conclusions,the theory of resolvent operators,the Banach contraction mapping principle,and fixed point theorems are used.While concluding,some examples are given to demonstrate the efficacy of the proposed results. 展开更多
关键词 nonlinear fractional differential equation Caputo fractional derivative mild solution existence and uniqueness theorems approximate controllability
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Normalized Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan XU Liping 《应用数学》 北大核心 2025年第1期14-29,共16页
In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with ... In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with prescribed 2-norm has some normalized solutions by introducing variational methods. 展开更多
关键词 nonlinear Choquard equation Potential function Variational method Normalized solution
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A New Technique for Constructing Higher-order Iterative Methods to Solve Nonlinear Systems
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作者 XIAO Xiaoyong 《应用数学》 北大核心 2025年第3期762-774,共13页
In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introduc... In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introducing only one additional evaluation of the function in each step.Furthermore,some new efficient methods with a higher-order of convergence are obtained by using only a single matrix inversion in each iteration.Analyses of convergence properties and computational efficiency of these new methods are made and testified by several numerical problems.By comparison,the new schemes are more efficient than the corresponding existing ones,particularly for large problem sizes. 展开更多
关键词 systems of nonlinear equation Order of convergence Higher-order method Extended Newton iteration Computational efficiency
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Investigating Solutions in Nonlinear Evolution Equations:A Focus on Local Existence in Mixed Types
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作者 NAFFISA Toureche Trouba FAN Long ABDELGHANI Dahou 《应用数学》 北大核心 2025年第3期691-702,共12页
With the urgent need to resolve complex behaviors in nonlinear evolution equations,this study makes a contribution by establishing the local existence of solutions for Cauchy problems associated with equations of mixe... With the urgent need to resolve complex behaviors in nonlinear evolution equations,this study makes a contribution by establishing the local existence of solutions for Cauchy problems associated with equations of mixed types.Our primary contribution is the establishment of solution existence,illuminating the dynamics of these complex equations.To tackle this challenging problem,we construct an approximate solution sequence and apply the contraction mapping principle to rigorously prove local solution existence.Our results significantly advance the understanding of nonlinear evolution equations of mixed types.Furthermore,they provide a versatile,powerful approach for tackling analogous challenges across physics,engineering,and applied mathematics,making this work a valuable reference for researchers in these fields. 展开更多
关键词 nonlinear evolution equation Contraction mapping principle Sobolev space Dissipative system
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STUDY ON EXACT ANALYTICAL SOLUTIONS FOR TWO SYSTEMS OF NONLINEAR EVOLUTION EQUATIONS 被引量:1
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作者 YAN Zhen-ya(闫振亚) +1 位作者 ZHANG Hong-qing(张鸿庆) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第8期925-934,共10页
The homogeneous balance method was improved and applied to two systems Of nonlinear evolution equations. As a result, several families of exact analytic solutions are derived by some new ansatzs. These solutions conta... The homogeneous balance method was improved and applied to two systems Of nonlinear evolution equations. As a result, several families of exact analytic solutions are derived by some new ansatzs. These solutions contain Wang's and Zhang's results and other new types of analytical solutions, such as rational fraction solutions and periodic solutions. The way can also be applied to solve more nonlinear partial differential equations. 展开更多
关键词 nonlinear evolution equations improved homogeneous balance method exact analytical solution solitary wave solution rational solution
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Nonlocal Symmetries to Systems of Nonlinear Diffusion Equations 被引量:1
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作者 QU Chang-Zheng KANG Jing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期9-16,共8页
In this paper, we study potential symmetries to certain systems of nonlinear diffusion equations. Thosesystems have physical applications in soil science, mathematical biology, and invariant curve flows in R^3. Lie po... In this paper, we study potential symmetries to certain systems of nonlinear diffusion equations. Thosesystems have physical applications in soil science, mathematical biology, and invariant curve flows in R^3. Lie point symmetries of the potential system, which cannot be projected to vector fields of the given dependent and independent variables, yield potential symmetries. The class of the system that admits potential symmetries is expanded. 展开更多
关键词 symmetry group system of nonlinear diffusion equation nonlocal symmetry
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ON THE ASYMPTOTIC SOLUTIONS OF BOUNDARY VALUE PROBLEMS FOR A CLASS OF SYSTEMS OF NONLINEAR DIFFERENTIAL EQUATIONS (Ⅰ) 被引量:1
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作者 JIANG Fu-ru(江福汝) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第3期282-293,共12页
A new method is applied to study the asymptotic behavior of solutions of boundary value problems for a class of systems of nonlinear differential equations u' = nu, epsilon nu' + f(x, u, u')nu' - g(x, ... A new method is applied to study the asymptotic behavior of solutions of boundary value problems for a class of systems of nonlinear differential equations u' = nu, epsilon nu' + f(x, u, u')nu' - g(x, u, u') nu = 0 (0 < epsilon much less than 1). The asymptotic expansions of solutions are constructed, the remainders are estimated. The former works are improved and generalized. 展开更多
关键词 system of nonlinear differential equations boundary value problems asymptotic solution
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Lyapunov-type Inequalities for a System of Nonlinear Differential Equations 被引量:1
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作者 wei geng-ping shi shao-yun 《Communications in Mathematical Research》 CSCD 2017年第3期205-214,共10页
This paper presents several new Lyapunov-type inequalities for a system of first-order nonlinear differential equations. Our results generalize and improve some existing ones.
关键词 Lyapunov-type inequality nonlinear differential equation Hamiltonian system
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WELL-POSEDNESS OF THE DISCRETE NONLINEAR SCHRODINGER EQUATIONS AND THE KLEIN-GORDON EQUATIONS
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作者 Yifei WU Zhibo YANG Qi ZHOU 《Acta Mathematica Scientia》 2025年第6期2447-2477,共31页
The primary objective of this paper is to investigate the well-posedness theories associated with the discrete nonlinear Schrodinger and Klein-Gordon equations.These theories encompass both local and global well-posed... The primary objective of this paper is to investigate the well-posedness theories associated with the discrete nonlinear Schrodinger and Klein-Gordon equations.These theories encompass both local and global well-posedness,as well as the existence of blowing-up solutions for large and irregular initial data.The main results presented in this paper can be summarized as follows:(1)Discrete Nonlinear Schrodinger Equation:Global well-posedness in l^(p) spaces for all1≤p≤∞,regardless of whether it is in the defocusing or focusing cases.(2)Discrete Klein-Gordon Equation:Local well-posedness in l^(p) spaces for all 1≤p≤∞.Furthermore,in the defocusing case,we establish global well-posedness in l^(p) spaces for any2≤p≤2σ+2(σ>0).In contrast,in the focusing case,we show that solutions with negative energy blow up within a finite time.These conclusions reveal the distinct dynamic behaviors exhibited by the solutions of the equations in discrete settings compared to their continuous setting.Additionally,they illuminate the significant role that discretization plays in preventing ill-posedness,and collapse for the nonlinear Schrodinger equation. 展开更多
关键词 discrete nonlinear Klein-Gordon equation discrete nonlinear Schrodinger equation WELL-POSEDNESS blow up l^(p)
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A Modified Hybrid Three-term Conjugate Gradient Projection Method for Constrained Nonlinear Monotone Equations
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作者 CHENG Mengfan WANG Qi +1 位作者 WANG Haijun LIU Jia 《数学理论与应用》 2025年第4期87-106,共20页
This paper presents a modified hybrid three-term conjugate gradient projection method(MHTTCGPM)for solving large-scale nonlinear monotone equations with convex set constraints.The method incorporates an adaptive line ... This paper presents a modified hybrid three-term conjugate gradient projection method(MHTTCGPM)for solving large-scale nonlinear monotone equations with convex set constraints.The method incorporates an adaptive line search technique,ensuring that the search direction satisfies the sufficient descent property.Without requiring Lipschitz continuity,the global convergence of the proposed method is rigorously established.Numerical results demonstrate the effectiveness and reliability of the new algorithm. 展开更多
关键词 nonlinear monotone equations Three-term conjugate gradient Global convergence Line search technique Convex set constraint
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A symmetric difference data enhancement physics-informed neural network for the solving of discrete nonlinear lattice equations
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作者 Jian-Chen Zhou Xiao-Yong Wen Ming-Juan Guo 《Communications in Theoretical Physics》 2025年第6期21-29,共9页
In this paper,we propose a symmetric difference data enhancement physics-informed neural network(SDE-PINN)to study soliton solutions for discrete nonlinear lattice equations(NLEs).By considering known and unknown symm... In this paper,we propose a symmetric difference data enhancement physics-informed neural network(SDE-PINN)to study soliton solutions for discrete nonlinear lattice equations(NLEs).By considering known and unknown symmetric points,numerical simulations are conducted to one-soliton and two-soliton solutions of a discrete KdV equation,as well as a one-soliton solution of a discrete Toda lattice equation.Compared with the existing discrete deep learning approach,the numerical results reveal that within the specified spatiotemporal domain,the prediction accuracy by SDE-PINN is excellent regardless of the interior or extrapolation prediction,with a significant reduction in training time.The proposed data enhancement technique and symmetric structure development provides a new perspective for the deep learning approach to solve discrete NLEs.The newly proposed SDE-PINN can also be applied to solve continuous nonlinear equations and other discrete NLEs numerically. 展开更多
关键词 symmetric difference data enhancement physics-informed neural network data enhancement symmetric point soliton solutions discrete nonlinear lattice equations
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Periodic lump,soliton,and some mixed solutions of the(2+1)-dimensional generalized coupled nonlinear Schrödinger equations
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作者 Xiao-Min Wang Ji Li Xiao-Xiao Hu 《Chinese Physics B》 2025年第11期340-350,共11页
The(2+1)-dimensional generalized coupled nonlinear Schrödinger equations with a four-wave mixing term are studied in this paper,which describe optical solitons in birefringent fibers.Utilizing the Hirota bilinear... The(2+1)-dimensional generalized coupled nonlinear Schrödinger equations with a four-wave mixing term are studied in this paper,which describe optical solitons in birefringent fibers.Utilizing the Hirota bilinear method,we systematically construct single-and double-periodic lump solutions.To provide a detailed insight into the dynamic behavior of the nonlinear waves,we explore diverse mixed solutions,including bright-dark,W-shaped,multi-peak,and bright soliton solutions.Building upon single-periodic lump solutions,we analyze the dynamics of lump waves on both plane-wave and periodic backgrounds using the long-wave limit method.Moreover,we obtain the interaction solutions involving lumps,periodic lumps,and solitons.The interactions among two solitons,multiple lumps,and mixed waves are illustrated and analyzed.Comparative analysis reveals that these multi-lump solutions exhibit richer dynamical properties than conventional single-lump ones.These results contribute to a deeper understanding of nonlinear systems and may facilitate solving nonlinear problems in nature. 展开更多
关键词 nonlinear Schrödinger equations lump solutions mixed solutions Hirota bilinear method
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A weak condition for secant method to solve systems of nonlinear equations
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作者 LIANG Ke-wei HAN Dan-fu +1 位作者 ZHANG Hong ZHU Cheng-yan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第1期90-96,共7页
In this paper, a new weak condition for the convergence of secant method to solve the systems of nonlinear equations is proposed. A convergence ball with the center x0 is replaced by that with xl, the first approximat... In this paper, a new weak condition for the convergence of secant method to solve the systems of nonlinear equations is proposed. A convergence ball with the center x0 is replaced by that with xl, the first approximation generated by the secant method with the initial data x-1 and x0. Under the bounded conditions of the divided difference, a convergence theorem is obtained and two examples to illustrate the weakness of convergence conditions are provided. Moreover, the secant method is applied to a system of nonlinear equations to demonstrate the viability and effectiveness of the results in the paper. 展开更多
关键词 secant method Banach space radius of convergence systems of nonlinear equations COMPLEXITY
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Existence and asymptotic behavior for systems of nonlinear hyperbolic equations
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作者 YE Yao-jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第4期453-465,共13页
The initial-boundary value problem for a class of nonlinear hyperbolic equations system in bounded domain is studied. The existence of global solutions for this problem is proved by constructing a stable set, and obta... The initial-boundary value problem for a class of nonlinear hyperbolic equations system in bounded domain is studied. The existence of global solutions for this problem is proved by constructing a stable set, and obtain the asymptotic stability of global solutions by means of a difference inequality. 展开更多
关键词 nonlinear hyperbolic equations system global solutions asymptotic behavior difference inequal-ity damping and source terms.
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Efficient Numerical Scheme for Solving Large System of Nonlinear Equations
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作者 Mudassir Shams Nasreen Kausar +2 位作者 Shams Forruque Ahmed Irfan Anjum Badruddin Syed Javed 《Computers, Materials & Continua》 SCIE EI 2023年第3期5331-5347,共17页
A fifth-order family of an iterative method for solving systems of nonlinear equations and highly nonlinear boundary value problems has been developed in this paper.Convergence analysis demonstrates that the local ord... A fifth-order family of an iterative method for solving systems of nonlinear equations and highly nonlinear boundary value problems has been developed in this paper.Convergence analysis demonstrates that the local order of convergence of the numerical method is five.The computer algebra system CAS-Maple,Mathematica,or MATLAB was the primary tool for dealing with difficult problems since it allows for the handling and manipulation of complex mathematical equations and other mathematical objects.Several numerical examples are provided to demonstrate the properties of the proposed rapidly convergent algorithms.A dynamic evaluation of the presented methods is also presented utilizing basins of attraction to analyze their convergence behavior.Aside from visualizing iterative processes,this methodology provides useful information on iterations,such as the number of diverging-converging points and the average number of iterations as a function of initial points.Solving numerous highly nonlinear boundary value problems and large nonlinear systems of equations of higher dimensions demonstrate the performance,efficiency,precision,and applicability of a newly presented technique. 展开更多
关键词 nonlinear equations convergence order boundary value problem computational time basins of attraction converging points
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Potential Symmetries to a System of Three-Component Nonlinear Diffusion Equations
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作者 XUE Chun-Rong QU Chang-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期193-198,共6页
A system of nonlinear diffusion equations with three components is studied via the potential symmetry method. It is shown that the system admits the potential symmetries for certain diffusion terms. The invariant solu... A system of nonlinear diffusion equations with three components is studied via the potential symmetry method. It is shown that the system admits the potential symmetries for certain diffusion terms. The invariant solutions assoeiated with the potential symmetries are obtained. 展开更多
关键词 Lie point symmetry potential symmetry nonlinear diffusion equation group-invariant solutions
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