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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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The analysis of drill string dynamics for extra-deep wells based on successive over-relaxation node iteration method
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作者 Wen-Chang Wang He-Yuan Yang +4 位作者 Da-Kun Luo Ming-Ming You Xing Zhou Feng Chen Qin-Feng Di 《Petroleum Science》 2025年第8期3293-3303,共11页
The complex vibration directly affects the dynamic safety of drill string in ultra-deep wells and extra-deep wells.It is important to understand the dynamic characteristics of drill string to ensure the safety of dril... The complex vibration directly affects the dynamic safety of drill string in ultra-deep wells and extra-deep wells.It is important to understand the dynamic characteristics of drill string to ensure the safety of drill string.Due to the super slenderness ratio of drill string,strong nonlinearity implied in dynamic analysis and the complex load environment,dynamic simulation of drill string faces great challenges.At present,many simulation methods have been developed to analyze drill string dynamics,and node iteration method is one of them.The node iteration method has a unique advantage in dealing with the contact characteristics between drill string and borehole wall,but its drawback is that the calculation consumes a considerable amount of time.This paper presents a dynamic simulation method of drilling string in extra-deep well based on successive over-relaxation node iterative method(SOR node iteration method).Through theoretical analysis and numerical examples,the correctness and validity of this method were verified,and the dynamics characteristics of drill string in extra-deep wells were calculated and analyzed.The results demonstrate that,in contrast to the conventional node iteration method,the SOR node iteration method can increase the computational efficiency by 48.2%while achieving comparable results.And the whirl trajectory of the extra-deep well drill string is extremely complicated,the maximum rotational speed downhole is approximately twice the rotational speed on the ground.The dynamic torque increases rapidly at the position of the bottom stabilizer,and the lateral vibration in the middle and lower parts of drill string is relatively intense. 展开更多
关键词 Extra-deep well Drill string dynamics Calculation speed-up method SOR iteration method
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Variational iteration method for solving the mechanism of the Equatorial Eastern Pacific El Nino-Southern Oscillation 被引量:35
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作者 莫嘉祺 王辉 +1 位作者 林万涛 林一骅 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第4期671-675,共5页
A class of coupled system for the E1 Nifio-Southern Oscillation (ENSO) mechanism is studied. Using the method of variational iteration for perturbation theory, the asymptotic expansions of the solution for ENSO mode... A class of coupled system for the E1 Nifio-Southern Oscillation (ENSO) mechanism is studied. Using the method of variational iteration for perturbation theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic behaviour of solution for corresponding problem is considered. 展开更多
关键词 nonlinear method of variational iteration perturbation theory El Nino- Southern Oscillation model
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Variational iteration solving method for El Nio phenomenon atmospheric physics of nonlinear model 被引量:14
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作者 MO Jiaqi WANG Hui +1 位作者 LIN Wantao LIN Yihua 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第5期35-38,共4页
A class of E1 Niйo atmospheric physics oscillation model is considered. The E1 Niйo atmospheric physics oscillation is an abnormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions. The conce... A class of E1 Niйo atmospheric physics oscillation model is considered. The E1 Niйo atmospheric physics oscillation is an abnormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions. The conceptual oscillator model should consider the variations of both the eastern and western Pacific anomaly patterns. An E1 Niйo atmospheric physics model is proposed using a method for the variational iteration theory. Using the variational iteration method, the approximate expansions of the solution of corresponding problem are constructed. That is, firstly, introducing a set of functional and accounting their variationals, the Lagrange multiplicators are counted, and then the variational iteration is defined, finally, the approximate solution is obtained. From approximate expansions of the solution, the zonal sea surface temperature anomaly in the equatorial eastern Pacific and the thermocline depth anomaly of the sea-air oscillation for E1 Niйo atmospheric physics model can be analyzed. E1 Niйo is a very complicated natural phenomenon. Hence basic models need to be reduced for the sea-air oscillator and are solved. The variational iteration is a simple and valid approximate method. 展开更多
关键词 NONLINEAR variational iteration method E1 Niйo phenomenon
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ON THE MONOTONE CONVERGENCE OF THE PROJECTED ITERATION METHODS FOR LINEAR COMPLEMENTARITY PROBLEMS 被引量:4
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作者 白中治 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1996年第2期228-233,共6页
Under suitable conditions,the monotone convergence about the projected iteration method for solving linear complementarity problem is proved and the influence of the involved parameter matrix on the convergence rate o... Under suitable conditions,the monotone convergence about the projected iteration method for solving linear complementarity problem is proved and the influence of the involved parameter matrix on the convergence rate of this method is investigated. 展开更多
关键词 LINEAR complementarity PROBLEM projected iteration method MONOTONE convergence.
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HIERARCHICAL ITERATION METHOD TO SOLVE DYNAMIC DIFFERENTIAL EQUATION 被引量:1
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作者 Dong Yunfeng(School of Astronautics, Beijing University of Aeronauticsand Astronautics, Beijing, China, 100083) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1997年第1期22-27,共6页
The dynamic differential equation of a multibody System can be presented inthe form of Aq= B. Calculating the inverse of matrix A is a simple way to solve this kindof differential equatbo. Matrix A will be in the ill ... The dynamic differential equation of a multibody System can be presented inthe form of Aq= B. Calculating the inverse of matrix A is a simple way to solve this kindof differential equatbo. Matrix A will be in the ill condition if the system is configured asa main they with small mass appendages. A hierarchical iteration method is given in thispaper to avoid the problem of the inverse of an ill condition matrix calculatbo. It is pont-ed out that the stability of the system input and output is the suffcient condition of itera-tion convergence. The method omits a series formula expanding step. It is also useful toreduce the immuence of the stiff problem. The calculation progress i8 modular and structural. 展开更多
关键词 dgnamics iteration differential equations hierarchical iteration method systems stability multibody system
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Fast and accurate adaptive collocation iteration method for orbit dynamic problems 被引量:2
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作者 Honghua DAI Zhe ZHANG +3 位作者 Xuechuan WANG Haoyang FENG Changtao WANG Xiaokui YUE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第9期231-242,共12页
For over half a century,numerical integration methods based on finite difference,such as the Runge-Kutta method and the Euler method,have been popular and widely used for solving orbit dynamic problems.In general,a sm... For over half a century,numerical integration methods based on finite difference,such as the Runge-Kutta method and the Euler method,have been popular and widely used for solving orbit dynamic problems.In general,a small integration step size is always required to suppress the increase of the accumulated computation error,which leads to a relatively slow computation speed.Recently,a collocation iteration method,approximating the solutions of orbit dynamic problems iteratively,has been developed.This method achieves high computation accuracy with extremely large step size.Although efficient,the collocation iteration method suffers from two limitations:(A)the computational error limit of the approximate solution is not clear;(B)extensive trials and errors are always required in tuning parameters.To overcome these problems,the influence mechanism of how the dynamic problems and parameters affect the error limit of the collocation iteration method is explored.On this basis,a parameter adjustment method known as the“polishing method”is proposed to improve the computation speed.The method proposed is demonstrated in three typical orbit dynamic problems in aerospace engineering:a low Earth orbit propagation problem,a Molniya orbit propagation problem,and a geostationary orbit propagation problem.Numerical simulations show that the proposed polishing method is faster and more accurate than the finite-difference-based method and the most advanced collocation iteration method. 展开更多
关键词 Collocation iteration method Numerical integration method Orbit dynamics Parameter adjustment method Polishing method
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Doubly Periodic Wave Solutions of Jaulent-Miodek Equations Using Variational Iteration Method Combined with Jacobian-function Method 被引量:2
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作者 ZHU Jia-Min LU Zhi-Ming LIU Yu-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1403-1406,共4页
One of the advantages of the variational iteration method is the free choice of initial guess. In this paper we use the basic idea of the Jacobian-function method to construct a generalized trial function with some un... One of the advantages of the variational iteration method is the free choice of initial guess. In this paper we use the basic idea of the Jacobian-function method to construct a generalized trial function with some unknown parameters. The Jaulent-Miodek equations are used to illustrate effectiveness and convenience of this method, some new explicit exact travelling wave solutions have been obtained, which include bell-type soliton solution, kink-type soliton solutions, solitary wave solutions, and doubly periodic wave solutions. 展开更多
关键词 Jaulent-Miodek equations Jacobian-function method variational iteration method doubly periodic wave solution exact solution
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A Unification of the Concepts of the Variational Iteration, Adomian Decomposition and Picard Iteration Methods;and a Local Variational Iteration Method 被引量:1
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作者 Xuechuan Wang Satya N.Atluri 《Computer Modeling in Engineering & Sciences》 SCIE EI 2016年第6期567-585,共19页
This paper compares the variational iteration method(VIM),the Adomian decomposition method(ADM)and the Picard iteration method(PIM)for solving a system of first o rder n onlinear o rdinary d ifferential e quations(ODE... This paper compares the variational iteration method(VIM),the Adomian decomposition method(ADM)and the Picard iteration method(PIM)for solving a system of first o rder n onlinear o rdinary d ifferential e quations(ODEs).A unification of the concepts underlying these three methods is attempted by considering a very general iterative algorithm for VIM.It is found that all the three methods can be regarded as special cases of using a very general matrix of Lagrange multipliers in the iterative algorithm of VIM.The global variational iteration method is briefly reviewed,and further recast into a Local VIM,which is much more convenient and capable of predicting long term complex dynamic responses of nonlinear systems even if they are chaotic. 展开更多
关键词 VARIATIONAL iteration method Adomian decomposition method PICARD iteration method ASYMPTOTIC technique nonlinear DYNAMICAL system
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Solutions of the Duffin-Kemmer-Petiau equation in the presence of Hulthn potential in(1+2) dimensions for unity spin particles using the asymptotic iteration method 被引量:1
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作者 Z.Molaee M.K.Bahar +1 位作者 F.Yasuk H.Hassanabadi 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期193-198,共6页
The relativistic Duffin-Kemmer-Petiau equation in the presence of Hulthen potential in (1 +2) dimensions for spin-one particles is studied. Hence, the asymptotic iteration method is used for obtaining energy eigenv... The relativistic Duffin-Kemmer-Petiau equation in the presence of Hulthen potential in (1 +2) dimensions for spin-one particles is studied. Hence, the asymptotic iteration method is used for obtaining energy eigenvalues and eigenfunctions. 展开更多
关键词 Duffin-Kemmer-Petiau equation Hulthen potential asymptotic iteration method
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Parametric Iteration Method for Solving Linear Optimal Control Problems 被引量:1
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作者 Abdolsaeed Alavi Aghileh Heidari 《Applied Mathematics》 2012年第9期1059-1064,共6页
This article presents the Parametric Iteration Method (PIM) for finding optimal control and its corresponding trajectory of linear systems. Without any discretization or transformation, PIM provides a sequence of func... This article presents the Parametric Iteration Method (PIM) for finding optimal control and its corresponding trajectory of linear systems. Without any discretization or transformation, PIM provides a sequence of functions which converges to the exact solution of problem. Our emphasis will be on an auxiliary parameter which directly affects on the rate of convergence. Comparison of PIM and the Variational Iteration Method (VIM) is given to show the preference of PIM over VIM. Numerical results are given for several test examples to demonstrate the applicability and efficiency of the method. 展开更多
关键词 PARAMETRIC iteration method Optimal Control Problem Pontryagin’s Maximum Principle He’s VARIATIONAL iteration method
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IMPROVED HOMOTOPY ITERATION METHOD AND APPLIED TO THE NINE-POINT PATH SYNTHESIS PROBLEM FOR FOUR-BAR LINKAGES 被引量:1
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作者 Zhang Jian Chen Yong (School of Mechanical Engineering, Southwest Jiaotong University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第1期10-16,共7页
A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast a... A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast and efficiently comparing to the original homotopy iteration method. Numerical examples for the ninepoint path synthesis of four-bar linkages show the advantages and efficiency of the improved homotopy iteration method. 展开更多
关键词 Homotopy function Homotopy iteration method Nine-point path synthesis Four-bar linkage
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Some geometrical iteration methods for nonlinear equations 被引量:1
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作者 LU Xing-jiang QIAN Chun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第1期25-30,共6页
This paper describes geometrical essentials of some iteration methods (e.g. Newton iteration, secant line method, etc.) for solving nonlinear equations and advances some geometrical methods of iteration that are fle... This paper describes geometrical essentials of some iteration methods (e.g. Newton iteration, secant line method, etc.) for solving nonlinear equations and advances some geometrical methods of iteration that are flexible and efficient. 展开更多
关键词 nonlinear equation iteration geometric method.
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A New Multidimensional Time Series Forecasting Method Based on the EOF Iteration Scheme 被引量:3
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作者 张邦林 刘洁 孙照渤 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期243-247,共5页
In this paper a new .mnultidimensional time series forecasting scheme based on the empirical orthogonal function (EOF) stepwise iteration process is introduced. The scheme is tested in a series of forecast experiments... In this paper a new .mnultidimensional time series forecasting scheme based on the empirical orthogonal function (EOF) stepwise iteration process is introduced. The scheme is tested in a series of forecast experiments of Nino3 SST anomalies and Tahiti-Darwin SO index. The results show that the scheme is feasible and ENSO predictable. 展开更多
关键词 SST A New Multidimensional Time Series Forecasting method Based on the EOF iteration Scheme Nino EOF
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Multilevel Iteration Methods for Solving Linear Operator Equations of the First Kind 被引量:2
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作者 罗兴钧 《Northeastern Mathematical Journal》 CSCD 2008年第1期1-9,共9页
In this paper we develop two multilevel iteration methods for solving linear systems resulting from the Galerkin method and Tikhonov regularization for linear ill-posed problems. The two algorithms and their convergen... In this paper we develop two multilevel iteration methods for solving linear systems resulting from the Galerkin method and Tikhonov regularization for linear ill-posed problems. The two algorithms and their convergence analyses are presented in an abstract framework. 展开更多
关键词 operator equations of the first kind ill-posed problem multilevel iteration method Tikhonov regularization
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An Iteration Method Based on Homotopy Function for Solving Polynomial Systems and Application to Mechanisms Problems 被引量:1
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作者 Chen Yong Yan Jing School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China 《Journal of Modern Transportation》 1997年第1期37-44,共8页
A new iterating method based on homotopy function is developed in this paper. All solutions can be found easily without the need of choosing proper initial values. Compared to the homotopy continuation method, the sol... A new iterating method based on homotopy function is developed in this paper. All solutions can be found easily without the need of choosing proper initial values. Compared to the homotopy continuation method, the solution process of the present method is simplified, and the computation efficiency as well as the reliability for obtaining all solutions is also improved. By application of the method to the mechanisms problems, the results are satisfactory. 展开更多
关键词 numerical iteration method homotopy iteration algorithm polynomial systems kinematic analysis and synthesis of mechanisms
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Multistage Numerical Picard Iteration Methods for Nonlinear Volterra Integral Equations of the Second Kind 被引量:1
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作者 Lian Chen Junsheng Duan 《Advances in Pure Mathematics》 2015年第11期672-682,共11页
Using the Picard iteration method and treating the involved integration by numerical quadrature formulas, we propose a numerical scheme for the second kind nonlinear Volterra integral equations. For enlarging the conv... Using the Picard iteration method and treating the involved integration by numerical quadrature formulas, we propose a numerical scheme for the second kind nonlinear Volterra integral equations. For enlarging the convergence region of the Picard iteration method, multistage algorithm is devised. We also introduce an algorithm for problems with some singularities at the limits of integration including fractional integral equations. Numerical tests verify the validity of the proposed schemes. 展开更多
关键词 VOLTERRA Integral Equation PICARD iteration method NUMERICAL Integration MULTISTAGE Scheme
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Mass Spectra of Heavy and Light Mesons Using Asymptotic Iteration Method 被引量:1
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作者 Richa Rani S.B.Bhardwaj Fakir ChAND 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第8期179-184,共6页
The non-relativistic radial Schr¨odinger equation is analytically solved using asymptotic iteration method within the framework of a general interaction potential whose special cases are the Cornell and Cornell p... The non-relativistic radial Schr¨odinger equation is analytically solved using asymptotic iteration method within the framework of a general interaction potential whose special cases are the Cornell and Cornell plus harmonic potentials. The energy eigenvalues expression is derived in three dimensional space, which is further used to calculate the mass spectra of ˉcc,ˉbb,ˉbc, cˉs, bˉs and b ˉq mesons. The obtained results of this work are in good agreement with experimental and other relativistic results and also improved in comparison with other non-relativistic recent studies. 展开更多
关键词 Schrodinger equation asymptotic iteration method mass spectra MESONS
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Integration of the Coupled Orbit-Attitude Dynamics Using Modified Chebyshev-Picard Iteration Methods 被引量:1
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作者 Xiaoli Bai John L.Junkins 《Computer Modeling in Engineering & Sciences》 SCIE EI 2016年第2期129-146,共18页
This paper presents Modified Chebyshev-Picard Iteration(MCPI)methods for long-term integration of the coupled orbit and attitude dynamics.Although most orbit predictions for operational satellites have assumed that th... This paper presents Modified Chebyshev-Picard Iteration(MCPI)methods for long-term integration of the coupled orbit and attitude dynamics.Although most orbit predictions for operational satellites have assumed that the attitude dynamics is decoupled from the orbit dynamics,the fully coupled dynamics is required for the solutions of uncontrolled space debris and space objects with high area-to-mass ratio,for which cross sectional area is constantly changing leading to significant change on the solar radiation pressure and atmospheric drag.MCPI is a set of methods for solution of initial value problems and boundary value problems.The methods refine an orthogonal function approximation of long-time-interval segments of state trajectories iteratively by fusing Chebyshev polynomials with the classical Picard iteration and have been applied to multiple challenging aerospace problems.Through the studies on integrating a torque-free rigid body rotation and a long-term integration of the coupled orbit-attitude dynamics through the effect of solar radiation pressure,MCPI methods are shown to achieve several times speedup over the Runge-Kutta 7(8)methods with several orders of magnitudes of better accuracy.MCPI methods are further optimized by integrating the decoupled dynamics at the beginning of the iteration and coupling the full dynamics when the attitude solutions and orbit solutions are converging during the iteration.The approach of decoupling and then coupling during iterations provides a unique and promising perspective on the way to warm start the solution process for the longterm integration of the coupled orbit-attitude dynamics.Furthermore,an attractive feature of MCPI in maintaining the unity constraint for the integration of quaternions within machine accuracy is illustrated to be very appealing. 展开更多
关键词 ORBIT propagation orbit-attitude dynamics MODIFIED Chebyshev-Picard iteration(MCPI)methods
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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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