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Constrained total least squares algorithm for passive location based on bearing-only measurements 被引量:27
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作者 WANG Ding ZHANG Li WU Ying 《Science in China(Series F)》 2007年第4期576-586,共11页
The constrained total least squares algorithm for the passive location is presented based on the bearing-only measurements in this paper. By this algorithm the non-linear measurement equations are firstly transformed ... The constrained total least squares algorithm for the passive location is presented based on the bearing-only measurements in this paper. By this algorithm the non-linear measurement equations are firstly transformed into linear equations and the effect of the measurement noise on the linear equation coefficients is analyzed, therefore the problem of the passive location can be considered as the problem of constrained total least squares, then the problem is changed into the optimized question without restraint which can be solved by the Newton algorithm, and finally the analysis of the location accuracy is given. The simulation results prove that the new algorithm is effective and practicable. 展开更多
关键词 passive location constrained total least squares algorithm newton algorithm
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Aircraft Modeling and Simulation with Cargo Moving Inside 被引量:22
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作者 陈杰 史忠科 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第2期191-197,共7页
Cargo airdrop has long been one of the most important measures to deal with urgent immediate needs, such as providing as- sists in military operations and sending relief to disaster areas, just to name a few. Because ... Cargo airdrop has long been one of the most important measures to deal with urgent immediate needs, such as providing as- sists in military operations and sending relief to disaster areas, just to name a few. Because it is carried out during flight, it is necessary to investigate the influences of the drop process on flight characteristics to ensure successful execution of the task. This article mainly studies the modeling of flight systems in large flying transport planes with cargo moving in it. By buildi... 展开更多
关键词 MODELS dynamics equation newton’s second law AIRDROP cargo moving
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Superlinear/Quadratic One-step Smoothing Newton Method for P_0-NCP 被引量:18
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作者 LiPingZHANG JiYeHAN ZhengHaiHUANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第1期117-128,共12页
We propose a one–step smoothing Newton method for solving the non-linearcomplementarity problem with P 0–function (P_0–NCP) based on the smoothing symmetric perturbedFisher function (for short, denoted as the SSPF... We propose a one–step smoothing Newton method for solving the non-linearcomplementarity problem with P 0–function (P_0–NCP) based on the smoothing symmetric perturbedFisher function (for short, denoted as the SSPF–function). The proposed algorithm has to solve onlyone linear system of equations and performs only one line search per iteration. Without requiringany strict complementarity assumption at the P_0–NCP solution, we show that the proposed algorithmconverges globally and superlinearly under mild conditions. Furthermore, the algorithm has localquadratic convergence under suitable conditions. The main feature of our global convergence resultsis that we do not assume a priori the existence of an accumulation point. Compared to the previousliteratures, our algorithm has stronger convergence results under weaker conditions. 展开更多
关键词 non–linear complementarity problems Smoothing newton method Superlinear/quadratic convergence
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NGLM:一类全局收敛的Newton-GMRES方法 被引量:14
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作者 安恒斌 白中治 《计算数学》 CSCD 北大核心 2005年第2期151-174,共24页
本文提出了一类具有全局收敛性质的Newton-GMRES方法-NGLM方法.该方法是对经典Newton-GMRES方法的推广.NGLM方法的全局策略是当在非精确Newton 方向上后退不能成功时,转而在一个子空间上运用信赖域方法确定迭代步长.理论分析与数值实验... 本文提出了一类具有全局收敛性质的Newton-GMRES方法-NGLM方法.该方法是对经典Newton-GMRES方法的推广.NGLM方法的全局策略是当在非精确Newton 方向上后退不能成功时,转而在一个子空间上运用信赖域方法确定迭代步长.理论分析与数值实验均表明,NGLM方法改善了Newton-GMRES方法的强健性. 展开更多
关键词 GMRES方法 全局收敛 newton LM方法 信赖域方法 收敛性质 数值实验 非精确 子空间 强健性 迭代
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ON THE GROWTH OF ZERO ORDER LAPLACE-STIELTJES TRANSFORM CONVERGENT IN THE RIGHT HALF-PLANE 被引量:15
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作者 孔荫莹 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2008年第2期431-440,共10页
In this article, authors study the growth of Laplace-Stieltjes transform with zero order convergent in the right half-plane, define the exponential order and the exponential low order, and find the relations between t... In this article, authors study the growth of Laplace-Stieltjes transform with zero order convergent in the right half-plane, define the exponential order and the exponential low order, and find the relations between them. Some results similar to Dirichlet series are obtained. 展开更多
关键词 Laplace-Stieltjes transforms of zero order newton polygon exponential order exponential low order
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Convergence of Newton's Method and Uniqueness of the Solution of Equations in Banach SpacesⅡ 被引量:15
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作者 XingHuaWANG ChongLI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第2期405-412,共8页
Some results on convergence of Newton's method in Banach spaces are established under the assumption that the derivative of the operators satisfies the radius or center Lipschitz condition with a weak L average.
关键词 Nonlinear operator equation newton's method Lipschitz condition with L average Convergence ball
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管内非Newton流体分数阶流动的精确解 被引量:16
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作者 同登科 王瑞和 杨河山 《中国科学(G辑)》 CSCD 2005年第3期318-326,共9页
研究了管内广义Oldroyd-B型流体轴向不稳态流动,将分数阶导数引入Oldroyd-B型流体的本构关系中,建立了带分数阶导数的广义Jeffreys模型.利用Hankel变换和离散逆Laplace变换技巧求得了常压力梯度的Poiseuille流动、环空管内轴向Couette... 研究了管内广义Oldroyd-B型流体轴向不稳态流动,将分数阶导数引入Oldroyd-B型流体的本构关系中,建立了带分数阶导数的广义Jeffreys模型.利用Hankel变换和离散逆Laplace变换技巧求得了常压力梯度的Poiseuille流动、环空管内轴向Couette流动、常轴向剪切应力的环空域轴向Couette流动和具有常压力梯度和常剪切应力的Poiseuille流动4种模型的精确解,Navier-Stokes流体的著名解,像Maxwell流体和二阶流体都是解的特殊情况. 展开更多
关键词 newton 精确解 Navier-Stokes 管内 COUETTE流动 Laplace变换 MAXWELL流体 HANKEL变换 分数阶导数 压力梯度 剪切应力 稳态流动 本构关系 特殊情况 二阶流体 轴向 s模型 B型 广义
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GPS精密星历拟合与插值中龙格现象的处理方法 被引量:12
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作者 吉长东 徐爱功 冯磊 《测绘科学》 CSCD 北大核心 2011年第6期169-171,共3页
采用广播星历和精密星历计算卫星位置是GPS定位基础,为确保精度可靠,广播星历由地面控制部分约每2小时更新一次,在对广播星历拟合与插值时有龙格现象发生,本文用Chebyshev和Legendre多项式拟合以及Lagrange、Neville和Newton插值方法对... 采用广播星历和精密星历计算卫星位置是GPS定位基础,为确保精度可靠,广播星历由地面控制部分约每2小时更新一次,在对广播星历拟合与插值时有龙格现象发生,本文用Chebyshev和Legendre多项式拟合以及Lagrange、Neville和Newton插值方法对精密星历内插,在对高次多项式拟合与插值数学机理认真分析研究的基础上,通过实验得出龙格现象的有效处理方法,对GPS精密星历高采样率拟合与插值具有参考意义。 展开更多
关键词 GPS精密星历 龙格现象(RP) 拟合与插值 CHEBYSHEV LEGENDRE LAGRANGE Neville newton
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ON SEMILOCAL CONVERGENCE OF INEXACT NEWTON METHODS 被引量:7
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作者 Xueping Guo 《Journal of Computational Mathematics》 SCIE EI CSCD 2007年第2期231-242,共12页
Inexact Newton methods are constructed by combining Newton's method with another iterative method that is used to solve the Newton equations inexactly. In this paper, we establish two semilocal convergence theorems f... Inexact Newton methods are constructed by combining Newton's method with another iterative method that is used to solve the Newton equations inexactly. In this paper, we establish two semilocal convergence theorems for the inexact Newton methods. When these two theorems are specified to Newton's method, we obtain a different Newton-Kantorovich theorem about Newton's method. When the iterative method for solving the Newton equations is specified to be the splitting method, we get two estimates about the iteration steps for the special inexact Newton methods. 展开更多
关键词 Banach space Systems of nonlinear equations newton's method The splittingmethod Inexact newton methods
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牛顿抑或奥尔特加?--一项来自高被引文献和获奖者视角的实证研究 被引量:13
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作者 姜春林 张立伟 刘学 《自然辩证法研究》 CSSCI 北大核心 2014年第11期79-85,共7页
牛顿认为,"我看得比别人更远,那是因为我站在巨人的肩上"。而奥尔特加认为,随着社会大众群体的崛起,社会大众将成为社会的主流群体。那么,在学术研究领域,是社会大众还是"巨人"(学术精英)构成科学研究的中坚力量,... 牛顿认为,"我看得比别人更远,那是因为我站在巨人的肩上"。而奥尔特加认为,随着社会大众群体的崛起,社会大众将成为社会的主流群体。那么,在学术研究领域,是社会大众还是"巨人"(学术精英)构成科学研究的中坚力量,并引导了学科的发展?本文以社会科学领域的图书情报学和工程技术领域的纳米技术为例,分别采集图书情报学和纳米技术领域的高被引文献数据,以及图书情报学和纳米技术领域的学术精英(图书情报学的5位普赖斯奖获得者和纳米技术领域的5位诺贝尔奖获得者)——获奖者所发表的文献数据。然后,通过检索选取文献的参考文献的被引次数数据得出如下结论:第一,高被引文献引用了更多的高被引文献;第二,学术精英也偏向引用高被引文献。研究结论支持了牛顿假说。 展开更多
关键词 牛顿 奥尔特加 高被引文献 学术精英
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ON NEWTON-HSS METHODS FOR SYSTEMS OF NONLINEAR EQUATIONS WITH POSITIVE-DEFINITE JACOBIAN MATRICES 被引量:11
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作者 Zhong-Zhi Bai Xue-Ping Guo 《Journal of Computational Mathematics》 SCIE CSCD 2010年第2期235-260,共26页
The Hermitian and skew-Hermitian splitting (HSS) method is an unconditionally convergent iteration method for solving large sparse non-Hermitian positive definite system of linear equations. By making use of the HSS... The Hermitian and skew-Hermitian splitting (HSS) method is an unconditionally convergent iteration method for solving large sparse non-Hermitian positive definite system of linear equations. By making use of the HSS iteration as the inner solver for the Newton method, we establish a class of Newton-HSS methods for solving large sparse systems of nonlinear equations with positive definite Jacobian matrices at the solution points. For this class of inexact Newton methods, two types of local convergence theorems are proved under proper conditions, and numerical results are given to examine their feasibility and effectiveness. In addition, the advantages of the Newton-HSS methods over the Newton-USOR, the Newton-GMRES and the Newton-GCG methods are shown through solving systems of nonlinear equations arising from the finite difference discretization of a two-dimensional convection-diffusion equation perturbed by a nonlinear term. The numerical implemen- tations also show that as preconditioners for the Newton-GMRES and the Newton-GCG methods the HSS iteration outperforms the USOR iteration in both computing time and iteration step. 展开更多
关键词 Systems of nonlinear equations HSS iteration method newton method Local convergence.
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等离子体浸没离子注入(PIII)过程中初始离子阵鞘层尺度内各物理量的时空演化 被引量:10
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作者 黄永宪 田修波 +3 位作者 杨士勤 黄志俊 Ricky Fu Paul K.Chu 《真空科学与技术学报》 EI CAS CSCD 北大核心 2005年第2期115-119,共5页
等离子体浸没离子注入(PIII)是用于材料表面改性的一种较新的、廉价的、非视线的技术。靶体被浸没在等离子体中,等离子体中的离子在靶体负脉冲偏压的作用下注入靶体而实现材料的表面改性。为了描述等离子体浸没离子注入过程,我们引用了... 等离子体浸没离子注入(PIII)是用于材料表面改性的一种较新的、廉价的、非视线的技术。靶体被浸没在等离子体中,等离子体中的离子在靶体负脉冲偏压的作用下注入靶体而实现材料的表面改性。为了描述等离子体浸没离子注入过程,我们引用了一维粒子模型(PIC)对其进行了数值模拟,该模型通过求解空间电势的Poisson方程,电子的Bolzmann分布以及离子在网格中受力运动的Newton运动方程来完成。本文重点研究了一个初始离子阵鞘层内电势、离子浓度、离子注入靶体的速度和动能以及离子流密度的时空演化规律。 展开更多
关键词 等离子体浸没离子注入 离子注人 鞘层 子阵 PⅢ 物理量 Poisson方程 材料表面改性 newton 时空演化规律 离子流密度 脉冲偏压 数值模拟 粒子模型 求解空间 运动方程 离子浓度 靶体 电势 一维 电子 动能
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两层扭转正多边形构成的中心构型 被引量:9
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作者 张世清 朱长荣 《中国科学(A辑)》 CSCD 北大核心 2002年第9期797-806,共10页
研究了R3中的一类特殊的两层扭转正多边形构成的中心构型的存在性.
关键词 两层扭转正多边形 2N体问题 中心构型 构型空间 newton N体问题 newton万有引力 质量 质点运动规律
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构造一种六阶牛顿迭代法解非线性方程组 被引量:6
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作者 张辉 陈豫眉 周琴 《山东师范大学学报(自然科学版)》 CAS 2017年第4期37-44,共8页
为求出非线性方程组的解,根据四点Newton-Cotes求积开公式,给出一种六阶的牛顿迭代方法,并分析该方法的收敛性.在数值算例中,针对不同的非线性方程组,运用该方法与现有几种迭代方法的实验结果进行比较,结果表明该方法具有较好的优势.
关键词 迭代法 newton newton-Cotes 非线性方程
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SMOOTHING NEWTON ALGORITHM FOR THE CIRCULAR CONE PROGRAMMING WITH A NONMONOTONE LINE SEARCH 被引量:8
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作者 迟晓妮 韦洪锦 +1 位作者 万仲平 朱志斌 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1262-1280,共19页
In this paper, we present a nonmonotone smoothing Newton algorithm for solving the circular cone programming(CCP) problem in which a linear function is minimized or maximized over the intersection of an affine space w... In this paper, we present a nonmonotone smoothing Newton algorithm for solving the circular cone programming(CCP) problem in which a linear function is minimized or maximized over the intersection of an affine space with the circular cone. Based on the relationship between the circular cone and the second-order cone(SOC), we reformulate the CCP problem as the second-order cone problem(SOCP). By extending the nonmonotone line search for unconstrained optimization to the CCP, a nonmonotone smoothing Newton method is proposed for solving the CCP. Under suitable assumptions, the proposed algorithm is shown to be globally and locally quadratically convergent. Some preliminary numerical results indicate the effectiveness of the proposed algorithm for solving the CCP. 展开更多
关键词 circular cone programming second-order cone programming nonmonotone line search smoothing newton method local quadratic convergence
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Soil Parameter Identification for Wheel-terrain Interaction Dynamics and Traversability Prediction 被引量:8
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作者 Suksun Hutangkabodee Yahya Hashem Zweiri +1 位作者 Lakmal Dasarath Seneviratne Kaspar Althoefer 《International Journal of Automation and computing》 EI 2006年第3期244-251,共8页
This paper presents a novel technique for identifying soil parameters for a wheeled vehicle traversing unknown terrain. The identified soil parameters are required for predicting vehicle drawbar pull and wheel drive t... This paper presents a novel technique for identifying soil parameters for a wheeled vehicle traversing unknown terrain. The identified soil parameters are required for predicting vehicle drawbar pull and wheel drive torque, which in turn can be used for traversability prediction, traction control, and performance optimization of a wheeled vehicle on unknown terrain. The proposed technique is based on the Newton Raphson method. An approximated form of a wheel-soil interaction model based on Composite Simpson's Rule is employed for this purpose. The key soil parameters to be identified are internal friction angle, shear deformation modulus, and lumped pressure-sinkage coefficient. The fourth parameter, cohesion, is not too relevant to vehicle drawbar pull, and is assigned an average value during the identification process. Identified parameters are compared with known values, and shown to be in agreement. The identification method is relatively fast and robust. The identified soil parameters can effectively be used to predict drawbar pull and wheel drive torque with good accuracy. The use of identified soil parameters to design a traversability criterion for wheeled vehicles traversing unknown terrain is presented. 展开更多
关键词 Soil parameter traversability newton Raphson Composite Simpson's Rule wheeled vehicle
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自适应多通道二维概率型时隙式随机多址无线通信网络协议分析 被引量:8
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作者 佘明辉 林琳 赵东风 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第3期232-237,共6页
针对时隙式二维概率型CSMA随机多址接入协议中,发送概率p1和检测概率p2不可调整,在重负载的情况下,其吞吐量下降的问题,提出了一种自适应多通道二维概率型时隙式随机多址接入协议(AdaptiveSlotted Two-dimensional Probability Multi-ch... 针对时隙式二维概率型CSMA随机多址接入协议中,发送概率p1和检测概率p2不可调整,在重负载的情况下,其吞吐量下降的问题,提出了一种自适应多通道二维概率型时隙式随机多址接入协议(AdaptiveSlotted Two-dimensional Probability Multi-channel and multi-access).用马尔可夫链的分析方法分析得到了该协议下负载均衡型无线通信网络系统的吞吐量和各优先级吞吐量的解析结果.仿真实验结果表明理论分析和仿真实验的一致性与合理性.通过与时隙式二维概率型接入协议的仿真比较说明该系统具有较好的性能. 展开更多
关键词 自适应二维概率型 随机多址 多通道 牛顿法
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ON DOMINATING SEQUENCE METHOD IN THE POINT ESTIMATE AND SMALE THEOREM 被引量:7
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作者 王兴华 韩丹夫 《Science China Mathematics》 SCIE 1990年第2期135-144,共10页
It can be optimized for the work of the point estimate on the Newton iteration, reported by Smale at the 20th Congress of Mathematicians in 1986. It has been proved that iffα(z,f) , for every analytic map f:E→F, z ... It can be optimized for the work of the point estimate on the Newton iteration, reported by Smale at the 20th Congress of Mathematicians in 1986. It has been proved that iffα(z,f) , for every analytic map f:E→F, z ∈ is an approximate zero of f,whereE and F are real or complex Banach spaces. In addition, if α,(z,f) , z is anapproximate zero of the second kind of f. 展开更多
关键词 dominating sequence point estimate newton ITERATION HIGHER-ORDER GENERALIZATION APPROXIMATE zero.
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A NOVEL SLIGHTLY COMPRESSIBLE MODEL FOR LOW MACH NUMBER PERFECT GAS FLOW CALCULATION 被引量:5
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作者 邓小刚 庄逢甘 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2002年第3期193-208,共16页
By analyzing the characteristics of low Mach number perfect gas flows, a novel Slightly Compressible Model (SCM) for low Mach number perect gas flows is derived. In view of numerical calculations, this model is proved... By analyzing the characteristics of low Mach number perfect gas flows, a novel Slightly Compressible Model (SCM) for low Mach number perect gas flows is derived. In view of numerical calculations, this model is proved very efficient, for it is kept within thep-v frame but does not have to satisfy the time consuming divergence-free condition in order to get the incompressible Navier-Stokes equation solution. Writing the equations in the form of conservation laws, we have derived the characteristic systems which are necessary for numerical calculations. A cell-centered finite-volume method with flux difference upwind-biased schemes is used for the equation solutions and a new Exact Newton Relaxation (ENR) implicit method is developed. Various computed results are presented to validate the present model. Laminar flow solutions over a circular cylinder with wake developing and vortex shedding are presented. Results for inviscid flow over a sphere are compared in excellent agreement with the exact analytic incompressible solution. Three-dimensional viscous flow solutions over sphere and prolate spheroid are also calculated and compared well with experiments and other incompressible solutions. Finally, good convergent performances are shown for sphere viscous flows. 展开更多
关键词 slightly compressible flow numerical simulations low Mach number flow calculations newton iteration relaxation algorithm
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Interpolation theory of anisotropic finite elements and applications 被引量:7
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作者 CHEN ShaoChun XIAO LiuChao 《Science China Mathematics》 SCIE 2008年第8期1361-1375,共15页
Interpolation theory is the foundation of finite element methods.In this paper,after reviewing some existed interpolation theorems of anisotropic finite element methods,we present a new way to analyse the interpolatio... Interpolation theory is the foundation of finite element methods.In this paper,after reviewing some existed interpolation theorems of anisotropic finite element methods,we present a new way to analyse the interpolation error of anisotropic elements based on Newton's formula of polynomial interpolation as well as its applications. 展开更多
关键词 interpolation theory anisotropic finite elements newton’s formula divided difference 65N30
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