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微分多项式系统的约化算法理论<英> 被引量:26
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作者 朝鲁 《数学进展》 CSCD 北大核心 2003年第2期208-220,共13页
本文中,作者推广了纯代数形式的特征列集理论(吴方法)为微分形式的相应理论,即建立了在机器证明和诸多微分问题中非常重要的微分多项式组的约化算法理论。引入了一些新的概念和观点使函数微分(导数)具有直观的代数几何表示。给出了Coher... 本文中,作者推广了纯代数形式的特征列集理论(吴方法)为微分形式的相应理论,即建立了在机器证明和诸多微分问题中非常重要的微分多项式组的约化算法理论。引入了一些新的概念和观点使函数微分(导数)具有直观的代数几何表示。给出了Coherent条件下的特征列集的算法。给出的算法易于在计算机上实现并适合应用于广泛的微分问题,如微分方程对称计算,各种微分关系的自动推理等问题。 展开更多
关键词 微分多项式系统 约化算法 吴方法 特征列集 微分多项式 基本集 约化 Coherent条件
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基于谐波平衡法的摆线钢球行星传动等速输出机构非线性动态特性研究 被引量:6
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作者 杨荣刚 安子军 《振动与冲击》 EI CSCD 北大核心 2017年第2期153-158,共6页
为揭示摆线钢球行星传动等速输出机构的非线性动力学行为,建立考虑机构钢球数目、输入激励、啮合副啮合状态及啮合刚度的纯扭转强非线性动力学模型。将啮合副预紧函数表现为多项式的形式,将啮合副间隙函数表达为描述函数的形式,通过谐... 为揭示摆线钢球行星传动等速输出机构的非线性动力学行为,建立考虑机构钢球数目、输入激励、啮合副啮合状态及啮合刚度的纯扭转强非线性动力学模型。将啮合副预紧函数表现为多项式的形式,将啮合副间隙函数表达为描述函数的形式,通过谐波平衡法将微分方程组转化为非线性代数方程组,利用MATLAB进行求解,得到系统的基频稳态响应。通过改变钢球数、轴向压缩量与啮合刚度,分析参数变化对系统非线性特性的影响。结果表明,预紧系统只有两阶频率激发共振,系统非线性程度随钢球数、啮合刚度和预紧量的增加而减弱,预紧量是影响系统非线性程度的主要因素;间隙系统激发共振频率的阶数与钢球数目有关,幅频响应曲线出现典型非线性特征,出现单边冲击与双边冲击现象。基于多项式函数的谐波平衡法为深入研究摆线钢球行星传动系统的动态特性提供了一种有效方法。 展开更多
关键词 摆线钢球行星传动 等速输出机构 谐波平衡法 幅频特性 轴向预紧 非线性振动
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亚纯函数涉及微分多项式的正规族
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作者 王皓然 杨祺 《五邑大学学报(自然科学版)》 CAS 2024年第2期9-13,26,共6页
本文研究了一类涉及微分多项式与分担值的正规定则.设n,k为2个正整数,令F是定义在复平面D上的一族亚纯函数,其零点重级至少k+1,a为一非零有穷复数,L (f)是关于f的微分多项式,且L(f)■0,若对■f,g∈F,都有f^(n)L(f)与g^(n)L(g)分担a,则F... 本文研究了一类涉及微分多项式与分担值的正规定则.设n,k为2个正整数,令F是定义在复平面D上的一族亚纯函数,其零点重级至少k+1,a为一非零有穷复数,L (f)是关于f的微分多项式,且L(f)■0,若对■f,g∈F,都有f^(n)L(f)与g^(n)L(g)分担a,则F在D上正规. 展开更多
关键词 正规族 亚纯函数 微分多项式 分担值
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A Collocation Technique via Pell-Lucas Polynomials to Solve Fractional Differential EquationModel for HIV/AIDS with Treatment Compartment
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作者 Gamze Yıldırım Suayip Yüzbası 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期281-310,共30页
In this study,a numerical method based on the Pell-Lucas polynomials(PLPs)is developed to solve the fractional order HIV/AIDS epidemic model with a treatment compartment.The HIV/AIDS mathematical model with a treatmen... In this study,a numerical method based on the Pell-Lucas polynomials(PLPs)is developed to solve the fractional order HIV/AIDS epidemic model with a treatment compartment.The HIV/AIDS mathematical model with a treatment compartment is divided into five classes,namely,susceptible patients(S),HIV-positive individuals(I),individuals with full-blown AIDS but not receiving ARV treatment(A),individuals being treated(T),and individuals who have changed their sexual habits sufficiently(R).According to the method,by utilizing the PLPs and the collocation points,we convert the fractional order HIV/AIDS epidemic model with a treatment compartment into a nonlinear system of the algebraic equations.Also,the error analysis is presented for the Pell-Lucas approximation method.The aim of this study is to observe the behavior of five populations after 200 days when drug treatment is applied to HIV-infectious and full-blown AIDS people.To demonstrate the usefulness of this method,the applications are made on the numerical example with the help of MATLAB.In addition,four cases of the fractional order derivative(p=1,p=0.95,p=0.9,p=0.85)are examined in the range[0,200].Owing to applications,we figured out that the outcomes have quite decent errors.Also,we understand that the errors decrease when the value of N increases.The figures in this study are created in MATLAB.The outcomes indicate that the presented method is reasonably sufficient and correct. 展开更多
关键词 Collocation method fractional differential equations HIV/AIDS epidemic model Pell-Lucas polynomials
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两类非线性微分差分方程的超越整函数解
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作者 徐俊峰 张阳意 《五邑大学学报(自然科学版)》 CAS 2024年第1期1-6,共6页
本文应用亚纯函数的Nevalinna值分布理论,研究两类非线性微分差分方程f^(n)+af^(n-2)f′+q(z)e^(Q(z))f^(k)(z+c)=P(z)和f(z)^(n)+L(f)+q(z)e^(Q(z)f(k))(z+c)=P(z)的超越整函数解的增长性及零点分布,得到了解的增长性估计和零点分类,这... 本文应用亚纯函数的Nevalinna值分布理论,研究两类非线性微分差分方程f^(n)+af^(n-2)f′+q(z)e^(Q(z))f^(k)(z+c)=P(z)和f(z)^(n)+L(f)+q(z)e^(Q(z)f(k))(z+c)=P(z)的超越整函数解的增长性及零点分布,得到了解的增长性估计和零点分类,这里L(f)是线性微分多项式,q(z),Q(z),P(z)是多项式. 展开更多
关键词 值分布 微分方程 整函数解
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关于f+a L(f)n的正规定则
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作者 冉娜 杨祺 《枣庄学院学报》 2024年第2期43-48,共6页
在f+a(f^(k))^(n)形式的基础上进行改进,将f(k)推广到关于f的微分多项式L(f),使条件更加一般化,推广已有的结论,并通过反证法,结合Zaclman-Pang引理,利用构造辅助函数的方式,分情况讨论并证明了两种关于f+a(L(f))^(n)形式的正规定则。... 在f+a(f^(k))^(n)形式的基础上进行改进,将f(k)推广到关于f的微分多项式L(f),使条件更加一般化,推广已有的结论,并通过反证法,结合Zaclman-Pang引理,利用构造辅助函数的方式,分情况讨论并证明了两种关于f+a(L(f))^(n)形式的正规定则。考虑例外值的情形,证明当f+a(L(f))^(n)≠b时,亚纯函数族F在区域D上是正规的。考虑分担值的情形,证明若L(f)的零值点不是f(z)的b值点,且对于亚纯函数族F内的任意两个函数f和g,f+a(L(f))^(n)和g+a(L(g))^(n)分担b,则F在区域D上正规。 展开更多
关键词 亚纯函数 正规族 微分多项式
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QUASIPERIODICITY OF TRANSCENDENTAL MEROMORPHIC FUNCTIONS
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作者 刘新玲 刘凯 +1 位作者 Risto KORHONEN Galina FILIPUK 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期161-172,共12页
This paper is devoted to considering the quasiperiodicity of complex differential polynomials,complex difference polynomials and complex delay-differential polynomials of certain types,and to studying the similarities... This paper is devoted to considering the quasiperiodicity of complex differential polynomials,complex difference polynomials and complex delay-differential polynomials of certain types,and to studying the similarities and differences of quasiperiodicity compared to the corresponding properties of periodicity. 展开更多
关键词 QUASIPERIODICITY meromorphic functions complex delay-differential polynomials Nevanlinna theory
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AN ARTIFICIAL BOUNDARY CONDITION FOR THE INCOMPRESSIBLE VISCOUS FLOWS IN A NO-SLIP CHANNEL 被引量:4
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作者 Han Hou-de Bao Wei-zhu(Department of Applied Mathematics, Tsinghua University, Beijing, China) 《Journal of Computational Mathematics》 SCIE CSCD 1995年第1期51-63,共13页
The numerical simulation of the steady incompressible viscous flows in a no-slip channel is considered. A discrete artificial boundary condition on a given segmental artificial boundary is designed by the method of li... The numerical simulation of the steady incompressible viscous flows in a no-slip channel is considered. A discrete artificial boundary condition on a given segmental artificial boundary is designed by the method of lines. Then the original problem is reduced to a boundary value problem of Navier-Stokes equations on a bounded domain. The numerical examples show that this artificial boundary condition is very effective and more accurate than Dirichlet and Neumann boundary conditions used in engineering literature. 展开更多
关键词 Boundary conditions Viscous flow EIGENVALUES APPROXIMATION Navier Stokes equation polynomials Ordinary differential equations
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Solving Fractional Integro-Differential Equations by Using Sumudu Transform Method and Hermite Spectral Collocation Method 被引量:5
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作者 Y.A.Amer A.M.S.Mahdy E.S.M.Youssef 《Computers, Materials & Continua》 SCIE EI 2018年第2期161-180,共20页
In this paper we are looking forward to finding the approximate analytical solutions for fractional integro-differential equations by using Sumudu transform method and Hermite spectral collocation method.The fractiona... In this paper we are looking forward to finding the approximate analytical solutions for fractional integro-differential equations by using Sumudu transform method and Hermite spectral collocation method.The fractional derivatives are described in the Caputo sense.The applications related to Sumudu transform method and Hermite spectral collocation method have been developed for differential equations to the extent of access to approximate analytical solutions of fractional integro-differential equations. 展开更多
关键词 Caputo derivative integro-differential equations hermite polynomials sumudu transform
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涉及零点个数的亚纯函数的正规定则
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作者 陈鹏斌 杨祺 《南阳师范学院学报》 CAS 2023年第6期29-34,共6页
研究了涉及零点个数的亚纯函数的正规定则,在一定程度上推广了前人一些相关结果,得到了相应的结果。
关键词 亚纯函数 正规族 微分多项式
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A Multiple q-translation Formula and Its Implications
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作者 Zhi Guo LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2023年第12期2338-2363,共26页
Using Hartogs'fundamental theorem for analytic functions in several complex variables,we establish a multiple q-exponential differential operational identity for the analytic functions in several variables,which c... Using Hartogs'fundamental theorem for analytic functions in several complex variables,we establish a multiple q-exponential differential operational identity for the analytic functions in several variables,which can be regarded as a multiple q-translation formula.This multiple q-translation formula is a fundamental result and play a pivotal role in q-mathematics.Using this q-translation formula,we can easily recover many classical conclusions in q-mathematics and derive some new q-formulas.Our work reveals some profound connections between the theory of complex functions in several variables and q-mathematics. 展开更多
关键词 Q-SERIES q-beta integral q-exponential differential operator q-translation Rogers-Szego polynomials
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亚纯函数的线性微分多项式分担一个小函数的唯一性 被引量:3
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作者 张毅 丁云娟 《广西工学院学报》 CAS 2010年第1期20-22,27,共4页
讨论了亚纯函数的线性微分多项式分担一个小函数的唯一性问题,所得定理推广了仪洪勋、杨力的结果.
关键词 亚纯函数 微分多项式 唯一性 小函数
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一种深度图像中的表面曲率估计算法 被引量:1
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作者 张涛 平西建 +1 位作者 柳葆芳 邵美珍 《数据采集与处理》 CSCD 2001年第1期47-51,共5页
曲率估计在深度图像分析中占有重要地位。传统的有限差分或局部拟合方法未考虑到表面上可能出现的不连续性 ,因而会不可避免地出现错误。为了得到有效可靠的曲率估计 ,本文提出了基于自适应局部表面拟合和鲁棒最大似然估计的曲率估计算... 曲率估计在深度图像分析中占有重要地位。传统的有限差分或局部拟合方法未考虑到表面上可能出现的不连续性 ,因而会不可避免地出现错误。为了得到有效可靠的曲率估计 ,本文提出了基于自适应局部表面拟合和鲁棒最大似然估计的曲率估计算法。首先 ,提出曲面是分片光滑的假设 ,表面曲率需从该像素所属的光滑曲面片来估计。其次 ,定义了一个能量函数来度量拟合窗的平滑度 ,在局部表面拟合时 ,依据最小化能量函数的原则来自适应移动拟合窗的中心 ,以使拟合窗达到最“光滑”。最后 ,采用鲁棒最大似然估计以消除仍然存在的“局外点”的影响。理论分析和实验结果证明估计算法是稳健、可靠、有效的且计算复杂度小。 展开更多
关键词 深度因素 微分几何 正交多项式 表面曲率估计算法 边缘检测
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微分多项式的值分布(英文) 被引量:2
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作者 高凌云 《数学杂志》 CSCD 北大核心 2003年第1期59-63,共5页
文[2-6]讨论了亚纯函效或代数体函数的微分多项式  及  的例外值问题。本文利用代效体函数的Nevanlinna值分布理论方法,研究了代数体函数的微分多项式的Picard值问题.推广了他们的结果。
关键词 代数体函数 值分布 微分多项式 亚纯函数
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Legendre小波在非线性分数阶微分方程中的应用 被引量:3
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作者 陈一鸣 孙慧 +1 位作者 刘丽丽 孙璐 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2013年第4期573-576,共4页
针对一类非线性分数阶微分方程,采用Legendre小波法对非线性分数阶微分方程进行研究.结合BlockPulse函数给出Legendre小波的分数阶积分算子矩阵,利用Block Pulse函数的定义与Legendre小波积分算子矩阵的性质将非线性分数阶微分方程转换... 针对一类非线性分数阶微分方程,采用Legendre小波法对非线性分数阶微分方程进行研究.结合BlockPulse函数给出Legendre小波的分数阶积分算子矩阵,利用Block Pulse函数的定义与Legendre小波积分算子矩阵的性质将非线性分数阶微分方程转换为非线性代数方程组,进而对其数值解和误差分析进行研究.结果表明:随着点数增多,数值解的精确度增加.数值算例验证了小波法的可行性和有效性. 展开更多
关键词 分数阶微分 非线性 LEGENDRE小波 LEGENDRE多项式 算子矩阵 blockpulse函数 数值解 CAPUTO导数
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一类微分多项式的零点的不等式估计 被引量:3
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作者 戴瑞芳 徐俊峰 《五邑大学学报(自然科学版)》 CAS 2017年第3期1-7,共7页
本文利用精简计数函数给出了微分多项式af^2(f^((k)))~n-1,n≥2的定量估计不等式,设f为超越亚纯函数,n,k为正整数,其中a(z)≠0为f(z)的小函数满足T(r,a)=S(r,f).
关键词 亚纯函数 微分多项式 小函数 值分布
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New Implementation of Legendre Polynomials for Solving Partial Differential Equations 被引量:1
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作者 Ali Davari Abozar Ahmadi 《Applied Mathematics》 2013年第12期1647-1650,共4页
In this paper we present a proposal using Legendre polynomials approximation for the solution of the second order linear partial differential equations. Our approach consists of reducing the problem to a set of linear... In this paper we present a proposal using Legendre polynomials approximation for the solution of the second order linear partial differential equations. Our approach consists of reducing the problem to a set of linear equations by expanding the approximate solution in terms of shifted Legendre polynomials with unknown coefficients. The performance of presented method has been compared with other methods, namely Sinc-Galerkin, quadratic spline collocation and LiuLin method. Numerical examples show better accuracy of the proposed method. Moreover, the computation cost decreases at least by a factor of 6 in this method. 展开更多
关键词 LEGENDRE polynomials PARTIAL differential EQUATIONS COLLOCATION Method
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THE LARGEST EIGENVALUE DISTRIBUTION OF THE LAGUERRE UNITARY ENSEMBLE 被引量:1
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作者 Shulin LYU Yang CHEN 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期439-462,共24页
We study the probability that all eigenvalues of the Laguerre unitary ensemble of n by n matrices are in (0, t), that is, the largest eigenvalue distribution. Associated with this probability, in the ladder operator... We study the probability that all eigenvalues of the Laguerre unitary ensemble of n by n matrices are in (0, t), that is, the largest eigenvalue distribution. Associated with this probability, in the ladder operator approach for orthogonal polynomials, there are recurrence coefficients, namely, an(t) and/3r, (t), as well as three auxiliary quantities, denoted by rn(t), Rn(t), σn(t). We establish the second order differential equations for both βn(t) and rn(t). By investigating the soft edge scaling limit when a - O(n) as n→ ∞ or a is finite, we derive a PH, the σ-form, and the asymptotic solution of the probability. In addition, we develop differential equations for orthogonal polynomials Pn (z) corresponding to the largest eigenvalue distribution of LUE and GUE with n finite or large. For large n, asymptotic formulas are given near the singular points of the ODE. Moreover, we are able to deduce a particular case of Chazy's equation for (t) = (t) with (t) satisfying the a-form of PIV or PV. 展开更多
关键词 Orthogonal polynomials Painleve equations differential equations
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Chebyshev Polynomial-Based Analytic Solution Algorithm with Efficiency, Stability and Sensitivity for Classic Vibrational Constant Coefficient Homogeneous IVPs with Derivative Orders n, n-1, n-2
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作者 David P. Stapleton 《American Journal of Computational Mathematics》 2022年第4期331-340,共10页
The Chebyshev polynomials are harnessed as functions of the one parameter of the nondimensionalized differential equation for trinomial homogeneous linear differential equations of arbitrary order n that have constant... The Chebyshev polynomials are harnessed as functions of the one parameter of the nondimensionalized differential equation for trinomial homogeneous linear differential equations of arbitrary order n that have constant coefficients and exhibit vibration. The use of the Chebyshev polynomials allows calculation of the analytic solutions for arbitrary n in terms of the orthogonal Chebyshev polynomials to provide a more stable solution form and natural sensitivity analysis in terms of one parameter and the initial conditions in 6n + 7 arithmetic operations and one square root. 展开更多
关键词 differential Equation STABILITY Sensitivity Analysis Chebyshev polynomials Coefficient Formula
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复平面上微分方程多项式解的符号算法
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作者 沈赤 《现代电力》 1996年第4期88-93,共6页
将一种基于Lanczosτ方法的符号计算方法用于求解一些满足一定边界条件的摄动微分方程的精确多项式解。τ方法表达式中利用了符号Faber多项式作为复平面上特定范围内的摄动项。此方法计算简便,且其精度优于同次的切比雪夫... 将一种基于Lanczosτ方法的符号计算方法用于求解一些满足一定边界条件的摄动微分方程的精确多项式解。τ方法表达式中利用了符号Faber多项式作为复平面上特定范围内的摄动项。此方法计算简便,且其精度优于同次的切比雪夫级数与Taylor级数。这里将以第一类Bessel函数J0(z)为例来介绍此方法。 展开更多
关键词 微分方程法 贝尔多项式 符号算法 贝塞尔函数
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