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UNSTEADY FLOWS OF A GENERALIZED SECOND GRADE FLUID WITH THE FRACTIONAL DERIVATIVE MODEL BETWEEN TWO PARALLEL PLATES 被引量:19
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作者 谭文长 徐明喻 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2004年第5期471-476,共6页
The fractional calculus approach in the constitutive relationship model of a generalized second grade fluid is introduced.Exact analytical solutions are obtained for a class of unsteady flows for the generalized secon... The fractional calculus approach in the constitutive relationship model of a generalized second grade fluid is introduced.Exact analytical solutions are obtained for a class of unsteady flows for the generalized second grade fluid with the fractional derivative model between two parallel plates by using the Laplace transform and Fourier transform for fractional calculus.The unsteady flows are generated by the impulsive motion or periodic oscillation of one of the plates.In addition,the solutions of the shear stresses at the plates are also determined. 展开更多
关键词 fractional derivative unsteady flows generalized second grade fluid parallel plates
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广义导数及其在极值问题中的应用
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作者 阮诗佺 于小珊 于野 《大学数学》 2024年第2期73-80,共8页
首先,将经典的导数概念推广到广义导数,通过研究广义导数的性质并结合等价无穷小的相关结论给出广义导数的简便计算方法;其次,引入导数指标的概念,并证明它是同阶无穷小等价关系的完全不变量;最后,将广义导数与导数指标应用到函数极值... 首先,将经典的导数概念推广到广义导数,通过研究广义导数的性质并结合等价无穷小的相关结论给出广义导数的简便计算方法;其次,引入导数指标的概念,并证明它是同阶无穷小等价关系的完全不变量;最后,将广义导数与导数指标应用到函数极值问题中,并给出极值的一个充分必要条件. 展开更多
关键词 广义导数 导数指标 等价无穷小 极值问题
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非线性跟踪─微分器在生育模式预测中的应用 被引量:5
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作者 姚翠珍 韩京清 《系统工程理论与实践》 EI CSCD 北大核心 1996年第2期57-61,共5页
本文根据跟踪-微分器跟踪信号及其微分的性质,我们并设计证明了二阶非线性跟踪-微分器,并利用它对生育模式进行了预测.
关键词 跟踪-微分器 生育模式 生育基数 人口统计
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ON QUADRATURE FORMULAE FOR SINGULAR INTEGRALS OF ARBITRARY ORDER 被引量:3
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作者 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期9-27,共19页
Some quadrature formulae for the numerical evaluation of singular integrals of arbitrary order are established and both the estimate of remainder and the convergence of each quadrature formula derived here are also gi... Some quadrature formulae for the numerical evaluation of singular integrals of arbitrary order are established and both the estimate of remainder and the convergence of each quadrature formula derived here are also given. 展开更多
关键词 Peano derivative generalized Hermite interpolation singular integral of arbitrary order singular quadrature formula
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索伯列夫空间形成溯因
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作者 李斐 王昌 杨艺芳 《科学技术哲学研究》 北大核心 2023年第5期102-108,共7页
圣彼得堡偏微分方程学派培养了索伯列夫研究偏微分方程的兴趣,哥廷根学派关于狄利克雷原理及将其用于研究偏微分方程边值问题的工作激励了索伯列夫的研究。在多重调和方程边值问题的驱动下,受冈瑟推广导数概念方法的影响,索伯列夫以其... 圣彼得堡偏微分方程学派培养了索伯列夫研究偏微分方程的兴趣,哥廷根学派关于狄利克雷原理及将其用于研究偏微分方程边值问题的工作激励了索伯列夫的研究。在多重调和方程边值问题的驱动下,受冈瑟推广导数概念方法的影响,索伯列夫以其处理双曲型方程时习得的研究思路和技巧为启示,借助测试函数通过积分恒等式推广了导数概念,在此基础上提出了完备的函数空间——索伯列夫空间。索伯列夫空间的提出促进了偏微分方程理论的发展,推进了变分法在数学物理方程中的应用,使狄利克雷原理得到了发展。 展开更多
关键词 索伯列夫空间 多重调和方程 直接变分方法 广义导数
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New generalized fuzzy transform computations for solving fractional partial differential equations arising in oceanography
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作者 Saima Rashid Rehana Ashraf Zakia Hammouch 《Journal of Ocean Engineering and Science》 SCIE 2023年第1期55-78,共24页
This paper presents a study of nonlinear waves in shallow water.The Korteweg-de Vries(KdV)equa-tion has a canonical version based on oceanography theory,the shallow water waves in the oceans,and the internal ion-acous... This paper presents a study of nonlinear waves in shallow water.The Korteweg-de Vries(KdV)equa-tion has a canonical version based on oceanography theory,the shallow water waves in the oceans,and the internal ion-acoustic waves in plasma.Indeed,the main goal of this investigation is to employ a semi-analytical method based on the homotopy perturbation transform method(HPTM)to obtain the numerical findings of nonlinear dispersive and fifth order KdV models for investigating the behaviour of magneto-acoustic waves in plasma via fuzziness.This approach is connected with the fuzzy generalized integral transform and HPTM.Besides that,two novel results for fuzzy generalized integral transforma-tion concerning fuzzy partial gH-derivatives are presented.Several illustrative examples are illustrated to show the effectiveness and supremacy of the proposed method.Furthermore,2D and 3D simulations de-pict the comparison analysis between two fractional derivative operators(Caputo and Atangana-Baleanu fractional derivative operators in the Caputo sense)under generalized gH-differentiability.The projected method(GHPTM)demonstrates a diverse spectrum of applications for dealing with nonlinear wave equa-tions in scientific domains.The current work,as a novel use of GHPTM,demonstrates some key differ-ences from existing similar methods. 展开更多
关键词 Fuzzy set theory Hukuhara differentiability KdV Equation generalized integral transform Caputo fractional derivative AB-Fractional operator Homotopy perturbation method
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二元序列的广义导数 被引量:2
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作者 陈鲁生 符方伟 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第4期36-41,共6页
以两种不同的方式对文献[1]中的二元序列的导数进行了推广,定义了两类不同的二元序列的广义导数,并且进一步讨论了周期为2N和2N-1的二元序列的广义导数的性质,推广了文献[1]的结果.
关键词 二元序列 周期 导数 广义导数
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A mathematical study of a tuberculosis model with fractional derivatives 被引量:3
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作者 Hamadjam Abboubakar Pushpendra Kumar +1 位作者 Vedat Suat Erturk Anoop Kumar 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2021年第4期215-240,共26页
In this work,we use a Predictor–Corrector method to implement and derive an iterative solution of an existing Tuberculosis(TB)model with two fractional derivatives,namely,Caputo–Fabrizio fractional derivative and th... In this work,we use a Predictor–Corrector method to implement and derive an iterative solution of an existing Tuberculosis(TB)model with two fractional derivatives,namely,Caputo–Fabrizio fractional derivative and the new generalized Caputo fractional derivative.We begin by recalling some existing results such as the basic reproduction number R0 and the equilibrium points of the model.Then,we study the global asymptotic stability of disease-free equilibrium of the fractional models.We also prove,for each fractional model,the existence and uniqueness of solutions.An iterative solution of the two models is computed using the Predictor–Corrector method.Using realistic parameter values,we perform numerical simulations for different values of the fractional order.Simulation results permit to conclude that the new generalized Caputo fractional derivative provides a more realistic analysis than the Caputo–Fabrizio fractional derivative and the classical integer-order TB model. 展开更多
关键词 TB model Caputo–Fabrizio(CF)fractional derivative asymptotic stability Predictor–Corrector Method(PCM) generalized Caputo derivative
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一类不可微多目标分式规划问题的最优性条件 被引量:2
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作者 张晓敏 吴泽忠 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第3期325-330,共6页
20世纪60年代诞生的凸分析已成为数学规划、变分学、最优化理论等学科的重要基础,但实际问题中大量函数是非凸函数,因此对凸函数进行多种形式的推广,出现各种广义凸函数,目前许多学者已研究了各类广义凸性条件下各类优化问题的最优性条... 20世纪60年代诞生的凸分析已成为数学规划、变分学、最优化理论等学科的重要基础,但实际问题中大量函数是非凸函数,因此对凸函数进行多种形式的推广,出现各种广义凸函数,目前许多学者已研究了各类广义凸性条件下各类优化问题的最优性条件、对偶理论等;对可微多目标规划问题的研究已相对成熟,对不可微多目标规划问题,在广义凸性下也得出一些结果.为研究有关局部Lipschitz函数的多目标分式规划问题,在广义Clarke梯度概念和非光滑(F,α,ρ,d)-凸函数的基础上给出广义非光滑(F,α,ρ,d)-凸函数的定义,在这些广义非光滑凸性的假设下得出一类不可微多目标分式规划问题的最优性条件. 展开更多
关键词 局部Lipschitz 广义导数 广义Clarke梯度 非光滑(F α ρ d)-凸函数 广义非光滑(F α ρ d)-凸函数
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EXISTENCE AND STABILITY RESULTS FOR GENERALIZED FRACTIONAL DIFFERENTIAL EQUATIONS 被引量:3
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作者 A.BEN MAKHLOUF D.BOUCENNA M.A.HAMMAMI 《Acta Mathematica Scientia》 SCIE CSCD 2020年第1期141-154,共14页
In this paper,a sufficient conditions to guarantee the existence and stability of solutions for generalized nonlinear fractional differential equations of orderα(1<α<2)are given.The main results are obtained b... In this paper,a sufficient conditions to guarantee the existence and stability of solutions for generalized nonlinear fractional differential equations of orderα(1<α<2)are given.The main results are obtained by using Krasnoselskii's fixed point theorem in a weighted Banach space.Two examples are given to demonstrate the validity of the proposed results. 展开更多
关键词 nonlinear FRACTIONAL differential EQUATIONS STABILITY analysis generalized FRACTIONAL derivative Krasnoselskii's fixed point THEOREM
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2-扭自由σ-素环上的广义导子的性质 被引量:2
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作者 李思晔 《佳木斯大学学报(自然科学版)》 CAS 2019年第6期1021-1022,共2页
利用了σ-素环以及2-扭自由σ-素环的性质,运用了替换法与线性化,讨论了2-扭自由σ-素环非零σ-Jordan理想上满足一定条件广义导子.R为2-扭自由σ-素环,θ、φ为R上的一个自同构,F是R→R的一个加性映射,有伴随(θ,φ)-导子d的广义(θ,... 利用了σ-素环以及2-扭自由σ-素环的性质,运用了替换法与线性化,讨论了2-扭自由σ-素环非零σ-Jordan理想上满足一定条件广义导子.R为2-扭自由σ-素环,θ、φ为R上的一个自同构,F是R→R的一个加性映射,有伴随(θ,φ)-导子d的广义(θ,φ)-导子,且d与对合σ可交换,J为R上的非零σ-Jordan理想。若J在R上同态,则d=0或J■Z(R).所得的结果推广了Aydin.N.和L.Oukhtite和Asma Ali的相关结果. 展开更多
关键词 2-扭自由σ-素环 Jordan理想 σ-Jordan理想 导子 广义导子 广义(θ φ)-导子 同态
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A New Definition for Generalized First Derivative of Nonsmooth Functions 被引量:1
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作者 Ali Vahidian Kamyad Mohammad Hadi Noori Skandari Hamid Reza Erfanian 《Applied Mathematics》 2011年第10期1252-1257,共6页
In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are ap... In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are applied for non-smooth functions which by solving these problems we obtain a kind of generalized first derivatives. For this purpose, a linear programming problem corresponding functional optimization problem is obtained which their optimal solutions give the approximate generalized first derivative. We show the efficiency of our approach by obtaining derivative and generalized derivative of some smooth and nonsmooth functions respectively in some illustrative examples. 展开更多
关键词 generalized derivative SMOOTH and NONSMOOTH FUNCTIONS FOURIER analysis Linear PROGRAMMING Functional Optimization
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σ-半素环上广义(θ,θ)-导子的性质 被引量:2
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作者 钟佩伶 《内江师范学院学报》 2020年第2期33-35,共3页
运用替换、线性化等代数方法研究将半素环上广义(θ,θ)-导子的性质推广到σ-半素环上.如果R是σ-半素环,θ是R上的自同构,设F是R上的广义(θ,θ)-导子,(θ,θ)-导子d是F的伴随导子,且d与σ都是可交换的.若F在R上作为同态,则有d=0.
关键词 半素环 广义(θ θ)-导子
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Approximate Derivative-Dependent Functional Variable Separation for the Generalized Diffusion Equations with Perturbation 被引量:1
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作者 张顺利 吉飞宇 屈长征 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第8期175-181,共7页
As an extension to the derivative-dependent functional variable separation approach, the approximate derivative-dependent functional variable separation approach is proposed, and it is applied to study the generalized... As an extension to the derivative-dependent functional variable separation approach, the approximate derivative-dependent functional variable separation approach is proposed, and it is applied to study the generalized diffusion equations with perturbation. Complete classification of these perturbed equations which admit approximate derivative-dependent functional separable solutions is obtained. As a result, the corresponding approximate derivative-dependent functional separable solutions to some resulting perturbed equations are derived by way of examples. 展开更多
关键词 generalized diffusion equation approximate derivative-dependent functional separable solution approximate generalized conditional symmetry
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OPTIMALITY CONDITIONS OF A CLASS OF SPECIAL NONSMOOTH PROGRAMMING
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作者 Song-baiSheng Hui-fuXu 《Journal of Computational Mathematics》 SCIE CSCD 2003年第6期791-800,共10页
In this paper, we investigate the optimality conditions of a class of special nonsmoothprogramming min F(x) = which arises from Li-norm optimization,where ci ∈ R is constant and fi ∈ C1,i = 1,2, ...,m. These conditi... In this paper, we investigate the optimality conditions of a class of special nonsmoothprogramming min F(x) = which arises from Li-norm optimization,where ci ∈ R is constant and fi ∈ C1,i = 1,2, ...,m. These conditions can easily be tested by computer. 展开更多
关键词 generalized gradient Directional derivative Optimality conditions Nons-mooth programming.
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THE INEFFICIENCY OF THE LEAST SQUARES ESTIMATOR AND ITS BOUND
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作者 杨虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第11期1087-1093,共7页
It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this... It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this paper we propose a new inefficiency of the least squares estimator with the measure of generalized variance and obtain its bound. 展开更多
关键词 inefficiency relative efficiency mean squared error generalized variance matrix derivative best linear unbased estimator
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FRACTIONAL DIFFUSION EQUATIONS WITH INTERNAL DEGREES OF FREEDOM
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作者 LuisVázquez 《Journal of Computational Mathematics》 SCIE CSCD 2003年第4期491-494,共4页
We present a generalization of the linear one-dimensional diffusion equation by combining the fractional derivatives and the internal degrees of freedom. The solutions are constructed from those of the scalar fraction... We present a generalization of the linear one-dimensional diffusion equation by combining the fractional derivatives and the internal degrees of freedom. The solutions are constructed from those of the scalar fractional diffusion equation. We analyze the interpolation between the standard diffusion and wave equations defined by the fractional derivatives. Our main result is that we can define a diffusion process depending on the internal degrees of freedom associated to the system. 展开更多
关键词 Fractional derivative DifFunors Diffusion process generalized Dirac equation.
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On Generalized High Order Derivatives of Nonsmooth Functions
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作者 Samaneh Soradi Zeid Ali Vahidian Kamyad 《American Journal of Computational Mathematics》 2014年第4期317-328,共12页
In this paper, we proposed a Extension Definition to derive, simultaneously, the first, second and high order generalized derivatives for non-smooth functions, in which the involved functions are Riemann integrable bu... In this paper, we proposed a Extension Definition to derive, simultaneously, the first, second and high order generalized derivatives for non-smooth functions, in which the involved functions are Riemann integrable but not necessarily locally Lipschitz or continuous. Indeed, we define a functional optimization problem corresponding to smooth functions where its optimal solutions are the first and second derivatives of these functions in a domain. Then by applying these functional optimization problems for non-smooth functions and using this method we obtain generalized first derivative (GFD) and generalized second derivative (GSD). Here, the optimization problem is approximated with a linear programming problem that by solving of which, we can obtain these derivatives, as simple as possible. We extend this approach for obtaining generalized high order derivatives (GHODs) of non-smooth functions, simultaneously. Finally, for efficiency of our approach some numerical examples have been presented. 展开更多
关键词 generalized derivative SMOOTH and NONSMOOTH Functions NONSMOOTH Optimization Problem Linear PROGRAMMING
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Generalized Schwarzian Derivatives and Analytic Morrey Spaces
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作者 JIN Jian-jun LI Hua-bing TANG Shu-an 《Chinese Quarterly Journal of Mathematics》 2019年第2期171-187,共17页
In this paper,we study univalent functions f for which log f’belongs to the analytic Morrey spaces.By using the characterization of higher order derivatives of functions in analytic Morrey spaces,we establish some ne... In this paper,we study univalent functions f for which log f’belongs to the analytic Morrey spaces.By using the characterization of higher order derivatives of functions in analytic Morrey spaces,we establish some new descriptions for the analytic Morrey domains in terms of two kinds of generalized Schwarzian derivatives. 展开更多
关键词 ANALYTIC MORREY SPACES UNIVALENT functions Schwarzian derivative generalized Schwarzian derivatives CARLESON measure
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广义导数及其应用 被引量:1
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作者 刘孝书 《广西右江民族师专学报》 2005年第3期11-15,共5页
文章提出了一种广义导数的概念,得到了广义导数的运算法则,以及连续函数的中值定理。
关键词 广义导数 中值定理 函数 连续 梯度
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