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Fractional Noether theorem and fractional Lagrange equation of multi-scale mechano-electrophysiological coupling model of neuron membrane 被引量:1
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作者 王鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期409-415,共7页
Noether theorem is applied to a variable order fractional multiscale mechano-electrophysiological model of neuron membrane dynamics.The variable orders fractional Lagrange equation of a multiscale mechano-electrophysi... Noether theorem is applied to a variable order fractional multiscale mechano-electrophysiological model of neuron membrane dynamics.The variable orders fractional Lagrange equation of a multiscale mechano-electrophysiological model of neuron membrane dynamics is given.The variable orders fractional Noether symmetry criterion and Noether conserved quantities are given.The forms of variable orders fractional Noether conserved quantities corresponding to Noether symmetry generators solutions of the model under different conditions are discussed in detail,and it is found that the expressions of variable orders fractional Noether conserved quantities are closely dependent on the external nonconservative forces and material parameters of the neuron. 展开更多
关键词 Hamilton’s principle Noether theorem fractional derivative multiscale electromechanical coupling neuron membrane
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LAGRANGE'S THEOREM FOR A CLASS OF NONHOLONOMICSYSTEMS AND ITS APPLICATION
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作者 李刚常 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第2期135-146,共12页
The stability problem for the manifold of equilibrium positions of a class of nonholonomic systems is studied is studied in this paper .Based on Liapunov's direct method and the definition of stability , Lagrange&... The stability problem for the manifold of equilibrium positions of a class of nonholonomic systems is studied is studied in this paper .Based on Liapunov's direct method and the definition of stability , Lagrange's theorem of holonomic systems is extended to a class of nonholonomic conservative systems and dissipative systems ,and a new expression is made to the relation between asymptotic stability for the manifold of equilibrium positions of this class of nonholonomic systems and dissipative forces .Twoexamples are finally given to illustrate the application of the theorems . 展开更多
关键词 nonholonomic system lagrange's theorem. manifold stability Liapunov's direct method
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Moser扭转定理在Lagrange稳定性中的应用(英文) 被引量:1
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作者 弭鲁芳 《数学进展》 CSCD 北大核心 2004年第4期477-488,共12页
本文利用Moser扭转定理证明了一类Duffing方程x’’+g(x)=e(t)的Lagrange稳定性,其中e(t)以1为周期,g:R→R具有下列性质:当x≥do时,g(x)是超线性的;当x≤-do时,g(x)是次线性的,其中do是一正常数.
关键词 Moser扭转定理 lagrange稳定性 DUFFING方程 拟周期运动 超线性
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R^s空间中Lagrange插值问题研究
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作者 李志斌 李伟 万朝燕 《大连交通大学学报》 CAS 2007年第4期1-4,共4页
研究空间Rs中多项式空间中的Lagrange插值问题.给出了R1和R2上Lagrange插值多项式的构造,同时,给出了R2上插值问题的几个例子.另外,给出了矩形网点上的Lagrange插值多项式和三角形网点上的Lagrange插值多项式.讨论了Rs空间中的Lagrange... 研究空间Rs中多项式空间中的Lagrange插值问题.给出了R1和R2上Lagrange插值多项式的构造,同时,给出了R2上插值问题的几个例子.另外,给出了矩形网点上的Lagrange插值多项式和三角形网点上的Lagrange插值多项式.讨论了Rs空间中的Lagrange插值多项式及其余项. 展开更多
关键词 lagrange插值 空间Rs 余项
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New Asymptotic Results on Fermat-Wiles Theorem
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作者 Kimou Kouadio Prosper Kouakou Kouassi Vincent Tanoé François 《Advances in Pure Mathematics》 2024年第6期421-441,共21页
We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Dio... We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Diophantine remainders of (a, b, c), an asymptotic approach based on Balzano Weierstrass Analysis Theorem as tools. We construct convergent infinite sequences and establish asymptotic results including the following surprising one. If z y = 1 then there exists a tight bound N such that, for all prime exponents p > N , we have xp yp zp. 展开更多
关键词 Fermat’s Last theorem Fermat-Wiles theorem Kimou’s Divisors Diophantine Quotient Diophantine Remainders Balzano Weierstrass Analysis theorem
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Small Modular Solutions to Fermat’s Last Theorem
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作者 Thomas Beatty 《Advances in Pure Mathematics》 2024年第10期797-805,共9页
The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infini... The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infinitely many solutions if the problem is recast in terms of modular arithmetic. Over a hundred years ago Issai Schur was able to show that for any n there is always a sufficiently large prime p0such that for all primes p≥p0the congruence xn+yn≡zn(modp)has a non-trivial solution. Schur’s argument wasnon-constructive, and there is no systematic method available at present to construct specific examples for small primes. We offer a simple method for constructing all possible solutions to a large class of congruences of this type. 展开更多
关键词 Fermat’s Last theorem Modular Arithmetic CONGRUENCEs Prime Numbers Primitive Roots Indices Ramsey Theory schur’s Lemma in Ramsey Theory
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基于L-S Lagrange函数的神经网络方法
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作者 彭爱民 《湖北大学学报(自然科学版)》 CAS 2012年第2期231-234,共4页
利用非线性规划的Log-Sigmoid(L-S)型Lagrange函数及其对偶问题的性质,提出一种求解优化问题的神经网络方法,并讨论网络的收敛性和稳定性条件,算例表明该神经网络能有效求解.
关键词 L-s lagrange函数 神经网络 渐近稳定
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Comparison of Numerical Approximations of One-Dimensional Space Fractional Diffusion Equation Using Different Types of Collocation Points in Spectral Method Based on Lagrange’s Basis Polynomials 被引量:1
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作者 Mushfika Hossain Nova Hasib Uddin Molla Sajeda Banu 《American Journal of Computational Mathematics》 2017年第4期469-480,共12页
Recently many research works have been conducted and published regarding fractional order differential equations. There are several approaches available for numerical approximations of the solution of fractional order... Recently many research works have been conducted and published regarding fractional order differential equations. There are several approaches available for numerical approximations of the solution of fractional order diffusion equations. Spectral collocation method based on Lagrange’s basis polynomials to approximate numerical solutions of one-dimensional (1D) space fractional diffusion equations are introduced in this research paper. The proposed form of approximate solution satisfies non-zero Dirichlet’s boundary conditions on both boundaries. Collocation scheme produce a system of first order Ordinary Differential Equations (ODE) from the fractional diffusion equation. We applied this method with four different sets of collocation points to compare their performance. 展开更多
关键词 Fractional Diffusion Equation spectral METHOD COLLOCATION METHOD lagranges BAsIs Polynomial
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利用Lagrange方程演绎Schrodinger方程的守恒定律
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作者 杨祺 张琦森 郑永刚 《保山学院学报》 2022年第5期51-54,共4页
在相对论量子场论中,可以将Draic方程通过最小作用量原理构造得到。与此类似,使用最小作用量原理也可以构造Schrodinger方程,并且将量子力学波函数比作经典场的话,波动力学的能量、动量、角动量守恒可以完全看成是经典场的结果。通过构... 在相对论量子场论中,可以将Draic方程通过最小作用量原理构造得到。与此类似,使用最小作用量原理也可以构造Schrodinger方程,并且将量子力学波函数比作经典场的话,波动力学的能量、动量、角动量守恒可以完全看成是经典场的结果。通过构造Schrodinger方程的Lagrange函数的方法,利用最小作用量原理来得到量子力学的守恒定律的微分形式——动量、能量、角动量的守恒方程,这些守恒定律分别对应空间、时间和转动的不变性,这一结果并不违背我们熟知的守恒量算符在Hilbert空间的内积的结果,并通过U(1)对称性可以得到概率流守恒。 展开更多
关键词 lagrange方程 sCHRODINGER方程 NOETHER定理 守恒定律
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The Sufficient and Necessary Condition of Lagrange Stability of Quasi-periodic Pendulum Type Equations
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作者 CONG FU-ZHONG LIANG XIN HAN YUE-CAI 《Communications in Mathematical Research》 CSCD 2010年第1期76-84,共9页
The quasi-periodic pendulum type equations are considered. A sufficient and necessary condition of Lagrange stability for this kind of equations is obtained. The result obtained answers a problem proposed by Moser und... The quasi-periodic pendulum type equations are considered. A sufficient and necessary condition of Lagrange stability for this kind of equations is obtained. The result obtained answers a problem proposed by Moser under the quasi-periodic case. 展开更多
关键词 lagrange stability pendulum type equation KAM theorem
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Whole Perfect Vectors and Fermat’s Last Theorem
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last theorem Whole Perfect Vectors sine and Cosine Functions Natural and Rational Vectors Fermat Vectors
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On Form Invariance,Lie Symmetry and Three Kinds of Conserved Quantities of Generalized Lagrange's Equations
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作者 ZHAO Shu-Hong LIANG Li-Fuoi School of Civil Engineering,Harbin Engineering University,Harbin 150001,China2 Engineering College,Northeast Agricultural University,Harbin 150030,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期37-42,共6页
In this paper,the form invariance and the Lie symmetry of Lagrange's equations for nonconservativesystem in generalized classical mechanics under the infinitesimal transformations of group are studied,and the Noet... In this paper,the form invariance and the Lie symmetry of Lagrange's equations for nonconservativesystem in generalized classical mechanics under the infinitesimal transformations of group are studied,and the Noether'sconserved quantity,the new form conserved quantity,and the Hojman's conserved quantity of system are derived fromthem.Finally,an example is given to illustrate the application of the result. 展开更多
关键词 form invariance Lie symmetry conserved quantity generalized classical mechanics lagranges equation
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Lagrange’s Spectral Collocation Method for Numerical Approximations of Two-Dimensional Space Fractional Diffusion Equation
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作者 Hasib Uddin Molla Mushfika Hossain Nova 《American Journal of Computational Mathematics》 2018年第2期121-136,共16页
Due to the ability to model various complex phenomena where classical calculus failed, fractional calculus is getting enormous attention recently. There are several approaches available for numerical approximations of... Due to the ability to model various complex phenomena where classical calculus failed, fractional calculus is getting enormous attention recently. There are several approaches available for numerical approximations of various types of fractional differential equations. For fractional diffusion equations spectral collocation is one of the efficient and most popular ap-proximation techniques. In this research, we introduce spectral collocation method based on Lagrange’s basis polynomials for numerical approximations of two-dimensional (2D) space fractional diffusion equations where spatial fractional derivative is described in Riemann-Liouville sense. We consider four different types of nodes to generate Lagrange’s basis polynomials and as collocation points in the proposed spectral collocation technique. Spectral collocation method converts the diffusion equation into a system of ordinary differential equations (ODE) for time variable and we use 4th order Runge-Kutta method to solve the resulting system of ODE. Two examples are considered to verify the efficiency of different types of nodes in the proposed method. We compare approximated solution with exact solution and find that Lagrange’s spectral collocation method gives very high accuracy approximation. Among the four types of nodes, nodes from Jacobi polynomial give highest accuracy and nodes from Chebyshev polynomials of 1st kind give lowest accuracy in the proposed method. 展开更多
关键词 lagranges sPECTRAL METHOD 2D FRACTIONAL Diffusion EQUATION COLLOCATION METHOD
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Dark Energy from Kaluza-Klein Spacetime and Noether’s Theorem via Lagrangian Multiplier Method
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作者 Mohamed S.El Naschie 《Journal of Modern Physics》 2013年第6期757-760,共4页
The supposedly missing dark energy of the cosmos is found quantitatively in a direct analysis without involving ordinary energy. The analysis relies on five dimensional Kaluza-Klein spacetime and a Lagrangian constrai... The supposedly missing dark energy of the cosmos is found quantitatively in a direct analysis without involving ordinary energy. The analysis relies on five dimensional Kaluza-Klein spacetime and a Lagrangian constrained by an auxiliary condition. Employing the Lagrangian multiplier method, it is found that this multiplier is equal to the dark energy of the cosmos and is given by where E is energy, m is mass, c is the speed of light, and λ is the Lagrangian multiplier. The result is in full agreement with cosmic measurements which were awarded the 2011 Nobel Prize in Physics as well as with the interpretation that dark energy is the energy of the quantum wave while ordinary energy is the energy of the quantum particle. Consequently dark energy could not be found directly using our current measurement methods because measurement leads to wave collapse leaving only the quantum particle and its ordinary energy intact. 展开更多
关键词 Dark Energy of the schrodinger Wave Quantum Measurement and the Missing Energy of the Cosmos Revising Einstein’s Relativity Kaluza-Klein Dark Energy lagrangian Multiplier as Dark Energy Noether’s theorem and Dark Energy
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Lagrange三角平动点邻近的相空间结构 被引量:3
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作者 周礼勇 孙义燧 周济林 《天文学报》 CSCD 北大核心 1999年第3期286-293,共8页
构造描述一类特殊平面圆型限制性三体问题的一个映射,并用这个映射讨论了该类三体问题Lagrange 三角平动点邻近的相空间结构以及它的稳定性,发现当两个主天体的质量比μ< 0 .02165 时,除去μ= 0 .01440 的... 构造描述一类特殊平面圆型限制性三体问题的一个映射,并用这个映射讨论了该类三体问题Lagrange 三角平动点邻近的相空间结构以及它的稳定性,发现当两个主天体的质量比μ< 0 .02165 时,除去μ= 0 .01440 的例外情况,三角平动点被不变曲线包围,是稳定的,这与理论结果相符,由此可解释特罗央群和希腊群小行星的稳定存在. 展开更多
关键词 lagrange平动点 小行星 映射方法 相空间结构
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用区间套定理证明Rolle定理、Lagrange定理 被引量:6
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作者 许在库 《安徽大学学报(自然科学版)》 CAS 2003年第2期18-21,共4页
Rolle定理和Lagarange定理是两个重要的微分中值定理,它们是Cauchy定理的基础,进一步为L'Hospital法则求极限提供了理论依据.它们还是研究函数增减性、凹凸性的基础.它在整个微分学中起着把微分的概念和方法应用于许多数学物理问题... Rolle定理和Lagarange定理是两个重要的微分中值定理,它们是Cauchy定理的基础,进一步为L'Hospital法则求极限提供了理论依据.它们还是研究函数增减性、凹凸性的基础.它在整个微分学中起着把微分的概念和方法应用于许多数学物理问题的桥梁作用.本文用区间套定理给出它的另一种证明. 展开更多
关键词 区间套定理 Ro11e定理 lagrange定理 微分中值定理 微分学 CAUCHY定理 L'Hospital法则
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基于Lagrange方法的平面双摆机构多体动力学研究 被引量:8
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作者 刘艳梨 朱永梅 《机械设计与制造》 北大核心 2009年第5期75-77,共3页
详细叙述了Lagrange方法的理论体系;针对一种平面双摆机构进行了动力学分析,采用Lagrange方法建立动力学模型;结合纽马克法,用VC++编制了自动建立平面双摆机构动力学模型的计算机程序,通过MATLAB软件模拟了平面双摆机构模型微振动时旋... 详细叙述了Lagrange方法的理论体系;针对一种平面双摆机构进行了动力学分析,采用Lagrange方法建立动力学模型;结合纽马克法,用VC++编制了自动建立平面双摆机构动力学模型的计算机程序,通过MATLAB软件模拟了平面双摆机构模型微振动时旋转角位移的动力学响应情况;从而为这种机构动力学特性的深入分析和结构优化设计提供了参考。 展开更多
关键词 动力学 lagrange方法 平面双摆机构 纽马克法
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一类非完整系统的Lagrange定理及其应用 被引量:1
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作者 李刚常 何世本 《应用数学和力学》 EI CSCD 北大核心 1998年第2期127-135,共9页
本文研究一类非完整系统平衡位置流形的稳定性问题·利用Ляпунов直接法和稳定性定义将完整系统的Lagrange定理推广到一类非完整保守系统与耗散系统,并对该类非完整系统平衡位置流形的渐近稳定性与耗散力间的关系作... 本文研究一类非完整系统平衡位置流形的稳定性问题·利用Ляпунов直接法和稳定性定义将完整系统的Lagrange定理推广到一类非完整保守系统与耗散系统,并对该类非完整系统平衡位置流形的渐近稳定性与耗散力间的关系作了新的表述,最后举例说明定理的应用· 展开更多
关键词 非完整系统 稳定性 流形 拉格朗日定理
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向量最优化问题的Lagrange对偶与择一定理 被引量:1
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作者 黄正海 胡适耕 沈轶 《应用数学》 CSCD 1997年第4期18-22,共5页
本文讨论无限维向量最优化问题的Lagrange对偶与弱对偶,建立了若干鞍点定理与弱鞍点定理.作为研究对偶问题的工具,建立了一个新的择一定理.
关键词 向量最优化 择一定理 拉格朗日对偶 最佳化
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一类向量极值问题的最优性条件和Lagrange对偶 被引量:2
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作者 王其林 李泽民 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第6期106-109,共4页
在序局部凸Hausdorff空间中利用广义次似凸映射下的择一定理,得出带集合约束的向量极值问题的一个最优性充要条件.利用此充要条件和二次G-可微函数的性质,获得了可微向量极值问题的几个最优性条件.最后,得到了此类向量极值问题的向量值L... 在序局部凸Hausdorff空间中利用广义次似凸映射下的择一定理,得出带集合约束的向量极值问题的一个最优性充要条件.利用此充要条件和二次G-可微函数的性质,获得了可微向量极值问题的几个最优性条件.最后,得到了此类向量极值问题的向量值Lagrange对偶. 展开更多
关键词 广义次似凸 择一定理 最优性条件 向量值lagrange对偶
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