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The Convergence Rate of Fréchet Distribution under the Second-Order Regular Variation Condition
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作者 Xilai Dai 《Journal of Applied Mathematics and Physics》 2024年第5期1597-1605,共9页
In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order ... In this article we consider the asymptotic behavior of extreme distribution with the extreme value index γ>0 . The rates of uniform convergence for Fréchet distribution are constructed under the second-order regular variation condition. 展开更多
关键词 convergence Rate Second-order Regular Variation Condition Fréchet Distribution Extreme Value Index
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Target Tracking Algorithm Using Finite-time Convergence Smooth Second-order Sliding Mode Controller for Mobile Robots 被引量:4
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作者 GE Lianzheng ZHAO Lijun GAO Tong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第3期414-419,共6页
Target tracking control for wheeled mobile robot (WMR) need resolve the problems of kinematics model and tracking algorithm.High-order sliding mode control is a valid method used in the nonlinear tracking control sy... Target tracking control for wheeled mobile robot (WMR) need resolve the problems of kinematics model and tracking algorithm.High-order sliding mode control is a valid method used in the nonlinear tracking control system,which can eliminate the chattering of sliding mode control.Currently there lacks the research of robustness and uncertain factors for high-order sliding mode control.To address the fast convergence and robustness problems of tracking target,the tracking mathematical model of WMR and the target is derived.Based on the finite-time convergence theory and second order sliding mode method,a nonlinear tracking algorithm is designed which guarantees that WMR can catch the target in finite time.At the same time an observer is applied to substitute the uncertain acceleration of the target,then a smooth nonlinear tracking algorithm is proposed.Based on Lyapunov stability theory and finite-time convergence,a finite time convergent smooth second order sliding mode controller and a target tracking algorithm are designed by using second order sliding mode method.The simulation results verified that WMR can catch up the target quickly and reduce the control discontinuity of the velocity of WMR. 展开更多
关键词 mobile robots second order sliding mode finite-time convergence OBSERVER
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Self-adaptive strategy for one-dimensional finite element method based on EEP method with optimal super-convergence order 被引量:4
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作者 袁驷 邢沁妍 +1 位作者 王旭 叶康生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第5期591-602,共12页
Based on the newly-developed element energy projection (EEP) method with optimal super-convergence order for computation of super-convergent results, an improved self-adaptive strategy for one-dimensional finite ele... Based on the newly-developed element energy projection (EEP) method with optimal super-convergence order for computation of super-convergent results, an improved self-adaptive strategy for one-dimensional finite element method (FEM) is proposed. In the strategy, a posteriori errors are estimated by comparing FEM solutions to EEP super-convergent solutions with optimal order of super-convergence, meshes are refined by using the error-averaging method. Quasi-FEM solutions are used to replace the true FEM solutions in the adaptive process. This strategy has been found to be simple, clear, efficient and reliable. For most problems, only one adaptive step is needed to produce the required FEM solutions which pointwise satisfy the user specified error tolerances in the max-norm. Taking the elliptical ordinary differential equation of the second order as the model problem, this paper describes the fundamental idea, implementation strategy and computational algorithm and representative numerical examples are given to show the effectiveness and reliability of the proposed approach. 展开更多
关键词 finite element method (FEM) self-adaptive solution super-convergence optimal convergence order element energy projection condensed shape functions
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QUASI-WEAK CONVERGENCE WITH APPLICATIONS IN ORDERED BANACH SPACE 被引量:1
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作者 杨光崇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第11期1291-1296,共6页
In the paper quasi_weak convergence is introduced in ordered Banach space and it is weaker than weak convergence. Besed on it, the fixed point existence theorem of increasing operator is proved without the suppose of ... In the paper quasi_weak convergence is introduced in ordered Banach space and it is weaker than weak convergence. Besed on it, the fixed point existence theorem of increasing operator is proved without the suppose of continuity and compactness in the sense of norm and weak compactness and is applied to the Hammerstein nonlinear intergal equation. 展开更多
关键词 ordered Banach space separated property quasi_weak convergence fixed points
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Convergence of a Sinusoidal Series with an Infinite Integral
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作者 Fate Shan Liping Zhu 《Advances in Pure Mathematics》 2023年第10期642-650,共9页
In this paper, we study the relationship between the convergence of the sinusoidal series and the infinity integrals (any real number α ∈[0,1], parameter p > 0). First of all, we study the convergence of the seri... In this paper, we study the relationship between the convergence of the sinusoidal series and the infinity integrals (any real number α ∈[0,1], parameter p > 0). First of all, we study the convergence of the series (any real number α ∈[0,1], parameter p > 0), mainly using the estimation property of the order to obtain that the series diverges when 0 p ≤1-α, the series converges conditionally when 1-α p ≤1, and the series converges absolutely when p >1. In the next part, we study the convergence state of the infinite integral (any real number α ∈[0,1], parameter p > 0), and get that when 0 p ≤1-α, the infinite integral diverges;when 1-α p ≤1, the infinite integral conditionally converges;when p >1, the infinite integral absolutely converges. Comparison of the conclusions of the above theorem, it is not difficult to derive the theorem: the level of and the infinity integral with the convergence of the state (any real number α ∈[0,1], the parameter p >0), thus promoting the textbook of the two with the convergence of the state requires the function of the general term or the product of the function must be monotonically decreasing conditions. 展开更多
关键词 Sinusoidal Series Estimation of order convergent States Infinite Integrals Discriminant Method
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ERRATA TO: “λ-Statistical Convergence of Order α” Acta Mathematica Scientia 2011, 31B(3): 953-959 被引量:1
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作者 R. olak . A. Bektas 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期2099-2100,共2页
The sequences defined in Example 3 and Example 4 do not serve our purpose for any λ = (λn). Because this sequences are just the sequences x = (xk) = (k) and x = (xk) = (1) respectively and any term of thes... The sequences defined in Example 3 and Example 4 do not serve our purpose for any λ = (λn). Because this sequences are just the sequences x = (xk) = (k) and x = (xk) = (1) respectively and any term of these sequences can not be 0. In this short not we give Example 3* and Example 4* to show that the inclusions given in Theorem 2.4 and Theorem 2.9 are strict for some λ = (λn) , α and β such that 0 α β ≤ 1. 展开更多
关键词 Statistical convergence of order Acta Mathematica Scientia 2011 ERRATA TO
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CONVERGENCE PROPERTIES OF HIGHER-ORDER MOMENT AND CUMULANT ESTIMATES 被引量:1
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作者 Li Hongwei(Institute of Information Science, Northern Jiaotong University, Beijing 100044)Cheng Qiansheng(School of Mathematical Sciences, Peking University, Beijing 100871) 《Journal of Electronics(China)》 1998年第3期240-247,共8页
The sample estimates of higher-order statistics are studied. Under certain conditions, the almost sure convergence of the third- and fourth-order moment and cumulant estimates of stationary processes is established. T... The sample estimates of higher-order statistics are studied. Under certain conditions, the almost sure convergence of the third- and fourth-order moment and cumulant estimates of stationary processes is established. The rate of almost sure convergence is obtained for the sample estimates of third- and fourth-order moment and cumulant. Additionally, it is shown that the third- and fourth-order moment and cumulant estimates are asymptotic normal. 展开更多
关键词 HIGHER-order MOMENT HIGHER-order CUMULANT ALMOST sure convergence convergence rate Asymptotic NORMALITY
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A Family of Methods for Solving Nonlinear Equations with Twelfth-Order Convergence 被引量:1
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作者 Xilan Liu Xiaorui Wang 《Applied Mathematics》 2013年第2期326-329,共4页
This paper presents a new family of twelfth-order methods for solving simple roots of nonlinear equations which greatly improves the order of convergence and the computational efficiency of the Newton’s method and so... This paper presents a new family of twelfth-order methods for solving simple roots of nonlinear equations which greatly improves the order of convergence and the computational efficiency of the Newton’s method and some other known methods. 展开更多
关键词 ITERATIVE Method Nonlinear Equation Twelfth-order convergence
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On the best convergence order of a new class of triangular summation operators
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作者 孟佳娜 赵连霞 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期399-401,共3页
In this paper, a new class of triangular summation operators based on the equidistant nodes was constructed. It is proved that this class of operators converges uniformly to arbitrary continuous fimctions with the per... In this paper, a new class of triangular summation operators based on the equidistant nodes was constructed. It is proved that this class of operators converges uniformly to arbitrary continuous fimctions with the period 2π on the whole axis, Fttrthermore, the best approximation order and the highest convergence order are obtained. In contrast to certain operators constructed by Bernstein and Kis in the previous works, the convergence properties of the new operator constructed in this paper are superior. 展开更多
关键词 triangular summation operator uniform convergence the best approxdmation order the highest convergence order
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A Class of Third-order Convergence Variants of Newton's Method
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作者 ZHAO Ling-ling WANG Xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期165-170,共6页
为非线性的方程解决根的第三顺序的集中方法的一个班,是变体牛顿的方法,是集中性质是的 given.Their proved.They 在多重 roots.In 附近是简单的根和一顺序集中附近的至少第三顺序集中结束,数字测试被给,与另外的已知的牛顿的 meth... 为非线性的方程解决根的第三顺序的集中方法的一个班,是变体牛顿的方法,是集中性质是的 given.Their proved.They 在多重 roots.In 附近是简单的根和一顺序集中附近的至少第三顺序集中结束,数字测试被给,与另外的已知的牛顿的 methods.The 相比,结果证明建议方法比 others.They 展开更多
关键词 一类三阶牛顿变形方法 非线性代数 解题方法 数学分析
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Result on the Convergence Behavior of Solutions of Certain System of Third-Order Nonlinear Differential Equations
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作者 Akinwale L. Olutimo 《International Journal of Modern Nonlinear Theory and Application》 2016年第1期48-58,共11页
Convergence behaviors of solutions arising from certain system of third-order nonlinear differential equations are studied. Such convergence of solutions corresponding to extreme stability of solutions when relates a ... Convergence behaviors of solutions arising from certain system of third-order nonlinear differential equations are studied. Such convergence of solutions corresponding to extreme stability of solutions when relates a pair of solutions of the system considered. Using suitable Lyapunov functionals, we prove that the solutions of the nonlinear differential equation are convergent. Result obtained generalizes and improves some known results in the literature. Example is included to illustrate the result. 展开更多
关键词 Nonlinear Differential Equations Third order convergence of Solutions Lyapunov Method
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Efficient Fast Independent Component Analysis Algorithm with Fifth-Order Convergence
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作者 Xuan-Sen He Tiao-Jiao Zhao Fang Wang 《Journal of Electronic Science and Technology》 CAS 2011年第3期244-249,共6页
Independent component analysis (ICA) is the primary statistical method for solving the problems of blind source separation. The fast ICA is a famous and excellent algorithm and its contrast function is optimized by ... Independent component analysis (ICA) is the primary statistical method for solving the problems of blind source separation. The fast ICA is a famous and excellent algorithm and its contrast function is optimized by the quadratic convergence of Newton iteration method. In order to improve the convergence speed and the separation precision of the fast ICA, an improved fast ICA algorithm is presented. The algorithm introduces an efficient Newton's iterative method with fifth-order convergence for optimizing the contrast function and gives the detail derivation process and the corresponding condition. The experimental results demonstrate that the convergence speed and the separation precision of the improved algorithm are better than that of the fast ICA. 展开更多
关键词 Index Terms---Blind source separation fast independent component analysis fifth-order convergence independent component analysis Newton's iterative method.
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CONVERGENCE AND GROWTH OF MULTIPLE DIRICHLET SERIES 被引量:5
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作者 梁美丽 高宗升 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1640-1648,共9页
This article investigates the convergence and growth of multiple Dirichlet series. The Valiron formula of Dirichlet series is extended to n-tuple Dirichlet series and an equivalence relation between the order of n-tup... This article investigates the convergence and growth of multiple Dirichlet series. The Valiron formula of Dirichlet series is extended to n-tuple Dirichlet series and an equivalence relation between the order of n-tuple Dirichlet series and its coefficients and exponents is obtained. 展开更多
关键词 multiple Dirichlet series convergent abscissa maximal module maximal term order
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Notes on Some Convergences in Riesz Space
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作者 陈志杰 艾富菊 《Journal of Southwest Jiaotong University(English Edition)》 2007年第2期175-178,共4页
An equivalent description of u-uniform convergence is presented first. Then the relations among the order convergence, u-uniform convergence and norm convergence of sequences are discussed in Riesz spaces. An equivale... An equivalent description of u-uniform convergence is presented first. Then the relations among the order convergence, u-uniform convergence and norm convergence of sequences are discussed in Riesz spaces. An equivalence of the three convergences is brought forward; namely, {fn} is a u-uniform Cauchy sequence. Finally the relations among the three convergences of sequences are also extended to the relations among the convergences of nets in Riesz spaces. 展开更多
关键词 Riesz space order convergence u-Uniform convergence Norm convergence NET
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Carbon productivity convergence club and its initial conditions: China's construction industry
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作者 Puwei Zhang Guangshe Jiaa +3 位作者 Qiang Mou Mingli Song Changquan He Qixiong Xu 《Chinese Journal of Population,Resources and Environment》 2019年第1期12-24,共13页
A three-stage method is proposed to study the convergence clubs for the dynamic total factor carbon productivity (DCP) and the initial conditions. The first stage is to measure the DCP that reflects the initial differ... A three-stage method is proposed to study the convergence clubs for the dynamic total factor carbon productivity (DCP) and the initial conditions. The first stage is to measure the DCP that reflects the initial difference. The second stage is to identify the convergence club of DCP. The last stage is to examine the initial factors that may affect the formation of the convergence club. Construction industry data from 30 provinces in China's Mainland from 2005 to 2016 were adopted to conduct an empirical study. The empirical results showed that (1) the arithmetic mean value of China’s provincial DCP showed an upward trend and the standard deviation showed an expanding trend.(2) There are five convergence clubs, but 13 provinces failed to converge to any club.(3) The higher the degree of construction industry marketization in 2005, the greater the probability that the provinces belong to a club with higher DCP. To improve the DCP, the effective diffusion of low-carbon construction technologies and the market-oriented reform of state-owned construction companies should be promoted. The three-stage method can also be applied to study different industries in different countries or regions. 展开更多
关键词 Total FACTOR carbon productivity CLUB convergence construction industry nonlinear time-varying FACTOR MODEL orderED LOGIT regression MODEL
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SOME RESEARCHES ON WEAK CONVERGENCE OF KERGIN INTERPOLATION
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作者 崔利宏 张洁琳 梁学章 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第4期340-350,共11页
The aim of this paper is to study the weak integral convergence of Kergin interpolation. The results of the weighted integral convergence and the weighted (partial) derivatives integral convergence of Kergin interpola... The aim of this paper is to study the weak integral convergence of Kergin interpolation. The results of the weighted integral convergence and the weighted (partial) derivatives integral convergence of Kergin interpolation polynomial for the smooth functions on the unit disk were obtained in the paper. Those generalized Liang's main results were acquired in 1998 to the more extensive situation. At the same time, the estimation of convergence rate of Kergin interpolation polynomial is given by means of introducing a new kind of smooth norm. 展开更多
关键词 Kergin插值 弱收敛 积分收敛 光滑函数
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A UNIFORMLY CONVERGENT SECOND ORDER DIFFERENCE SCHEME FOR A SINGULARLY PERTURBED SELF-ADJOINT ORDINARY DIFFERENTIAL EQUATION IN CONSERVATION FORM
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作者 郭雯 林鹏程 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第3期231-241,共11页
In this paper, based on the idea of El-Mistikawy and Werle[1] we construct a difference scheme for a singularly perturbed self-adjoint ordinary differential equation in conservation form. We prove that it is a uniform... In this paper, based on the idea of El-Mistikawy and Werle[1] we construct a difference scheme for a singularly perturbed self-adjoint ordinary differential equation in conservation form. We prove that it is a uniformly convergent second order scheme. 展开更多
关键词 exp A UNIFORMLY convergENT SECOND order DIFFERENCE SCHEME FOR A SINGULARLY PERTURBED SELF-ADJOINT ORDINARY DIFFERENTIAL EQUATION IN CONSERVATION FORM
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The Convergences Comparison between the Halley’s Method and Its Extended One Based on Formulas Derivation and Numerical Calculations
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作者 Shunji Horiguchi 《Applied Mathematics》 2016年第18期2394-2410,共17页
The purpose of this paper is that we give an extension of Halley’s method (Section 2), and the formulas to compare the convergences of the Halley’s method and extended one (Section 3). For extension of Halley’s met... The purpose of this paper is that we give an extension of Halley’s method (Section 2), and the formulas to compare the convergences of the Halley’s method and extended one (Section 3). For extension of Halley’s method we give definition of function by variable transformation in Section 1. In Section 4 we do the numerical calculations of Halley’s method and extended one for elementary functions, compare these convergences, and confirm the theory. Under certain conditions we can confirm that the extended Halley’s method has better convergence or better approximation than Halley’s method. 展开更多
关键词 Recurrence Formula Newton’s Method Halley’s Method Extension of Halley’s Method Third-order convergence
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基于二阶滑模扰动观测的PMSM电流预测控制研究
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作者 林立 胡俊 +2 位作者 谭乐 李亚楠 王翔 《自动化与信息工程》 2024年第3期22-31,共10页
针对无差拍电流预测控制(DPCC)对电机参数的依赖性,系统性能尤其易受电感参数影响的问题,研究基于二阶滑模扰动观测的永磁同步电机(PMSM)电流预测控制方法。首先,根据滑模控制原理分析电感参数失配对系统参数鲁棒性的影响,及传统滑模控... 针对无差拍电流预测控制(DPCC)对电机参数的依赖性,系统性能尤其易受电感参数影响的问题,研究基于二阶滑模扰动观测的永磁同步电机(PMSM)电流预测控制方法。首先,根据滑模控制原理分析电感参数失配对系统参数鲁棒性的影响,及传统滑模控制的不连续函数导致的系统“抖振”;然后,在DPCC中引入一种基于二阶趋近律的滑模扰动观测器(SMDO),实时补偿电感参数失配造成的扰动,同时通过二阶趋近律加速扰动误差的收敛;最后,将该方法与DPCC、SMDO+DPCC进行对比仿真实验。实验结果表明,在电感参数失配的情况下,该方法降低了电流稳态误差,提高了系统参数的鲁棒性,减少了传统滑模控制带来的系统“抖振”现象。 展开更多
关键词 永磁同步电机 无差拍电流预测控制 滑模控制 二阶趋近律 滑模扰动观测器
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空间分布阶时间分数阶扩散方程的高精度算法
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作者 龚珊珊 陈景华 刘欣然 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期321-328,共8页
[目的]目前空间分布阶方程的求解多为时间整数阶,且空间的收敛阶大多为二阶和三阶,很难达到四阶,为了提高Riesz空间分布阶Caputo时间分数阶扩散方程求解过程中的空间收敛精度,提出一种高阶的有限差分法.[方法]基于数值解法对Caputo时间... [目的]目前空间分布阶方程的求解多为时间整数阶,且空间的收敛阶大多为二阶和三阶,很难达到四阶,为了提高Riesz空间分布阶Caputo时间分数阶扩散方程求解过程中的空间收敛精度,提出一种高阶的有限差分法.[方法]基于数值解法对Caputo时间分数阶导数采用L1插值逼近离散;分布阶导数利用复化Simpson求积公式,将分布阶微分方程转化为一个多项Riesz空间分数阶导数的微分方程;从而构造方程的高阶数值离散格式,并运用矩阵分析的方法证明该数值格式具有稳定性和收敛性.[结果]在求解该分布阶微分方程中,该数值方法使得空间和分布阶的收敛阶达都达到了四阶,时间上的收敛阶达到了2-β阶.[结论]本文构造出的Riesz空间分布阶Caputo时间分数阶扩散方程的高阶差分格式,可使得空间上的收敛阶达到四阶,适用于高精度求解场景. 展开更多
关键词 分布阶 有限差分 稳定性 收敛性
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