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一类非线性色散方程中的新型奇异孤立波 被引量:14
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作者 殷久利 田立新 《物理学报》 SCIE EI CAS CSCD 北大核心 2009年第6期3632-3636,共5页
研究一类非线性色散广义DGH方程的新型奇异孤立波及其Painlev啨可积性.利用Painlev啨分析发现当对流项强度m=2时广义DGH方程是可积的,这是一个新的可积方程.通过构造新的变量代换以及auto-Backlund变换获得该方程丰富的奇异孤立波解,如... 研究一类非线性色散广义DGH方程的新型奇异孤立波及其Painlev啨可积性.利用Painlev啨分析发现当对流项强度m=2时广义DGH方程是可积的,这是一个新的可积方程.通过构造新的变量代换以及auto-Backlund变换获得该方程丰富的奇异孤立波解,如紧孤立波(compacton)、尖峰孤立波(peakon)、新型带尖点的双孤立波和带爆破点的双孤立波等. 展开更多
关键词 非线性色散方程 可积性 奇异孤立波
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Riccati方程可积的一个充分条件 被引量:14
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作者 冯录祥 《渭南师范学院学报》 2003年第2期7-9,共3页
给出了Riccati方程y′=P(x)y2+Q(x)y+R(x)可积的一个充分条件以及对应的通积分.该条件容易验证.
关键词 RICCATI方程 可积 充分条件 推广 通积分
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一类一阶非线性微分方程封闭可积条件 被引量:13
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作者 张孝理 《数学的实践与认识》 CSCD 北大核心 2001年第6期740-749,共10页
本文得到了较为广泛的一类一阶非线性微分方程的封闭可积充分条件 ,其实用性之一表现在著名的 Riccati方程和
关键词 非线性微分方程 通解 封闭可积 充分条件 RICCATI方程 Appel方程
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分段函数、函数的可积性与原函数存在性 被引量:11
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作者 马保国 王延军 《大学数学》 2009年第2期200-203,共4页
论述了分段函数在数学分析中的作用,并以分段函数为工具,给出了函数的原函数存在和黎曼可积之间的关系,有助于全面掌握原函数和定积分这两个重要概念.
关键词 分段函数 可积性 原函数 间断点
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The Hjek-Rnyi Inequlity For Banach Space Valued Random Variable Sequences and Its Application 被引量:7
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作者 Gan Shixin Department of Mathematics,Wuhan University,Wuhan 430072,China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第1期15-20,共6页
In this paper we prove the following Hajek Renyi inequality:Let 0<p≤1 ,then for any Banach space B , any L p integrable B valued random variable sequence {D n,n≥1} ,any real number sequence {b... In this paper we prove the following Hajek Renyi inequality:Let 0<p≤1 ,then for any Banach space B , any L p integrable B valued random variable sequence {D n,n≥1} ,any real number sequence {b n,n≥1} with 0<b n↑∞ ,any integer n≥1 ,there exits a constant C=C p>0 (only depending on p ) such thatP( sup j≥nji=1D ib j≥ε)≤Cε -p (∞j=n+1E‖D j‖ pb p j+nj=1E‖D j‖ pb p n) In the other direction,we prove some strong laws of large numbers and the integrability of the maximal functions for B valued random variable sequences by using this inequality and the Hajeck Renyi inequality we have obtained recently.Some known results are extended and improved. 展开更多
关键词 P smoothable space space of type P Banach space valued martingale strong law of large numbers integrability of the maximal function
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狄利克雷函数与黎曼函数的性质 被引量:9
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作者 何越 《河南教育学院学报(自然科学版)》 2013年第4期25-27,共3页
总结并证明了狄利克雷函数与黎曼函数的性质,主要包括奇偶性、周期性、连续性、可微性、可积性.特别地,引入极限函数描述狄利克雷函数,并在连续性中引入了上、下半连续.
关键词 狄利克雷函数 黎曼函数 连续 可导 可积
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Stochastic averaging of quasi-Hamiltonian systems 被引量:3
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作者 朱位秋 《Science China Mathematics》 SCIE 1996年第1期97-107,共11页
A stochastic averaging method is proposed for quasi-Hamiltonian systems (Hamiltonian systems with light dampings subject to weakly stochastic excitations). Various versions of the method, depending on whether the asso... A stochastic averaging method is proposed for quasi-Hamiltonian systems (Hamiltonian systems with light dampings subject to weakly stochastic excitations). Various versions of the method, depending on whether the associated Hamiltonian systems are integrable or nonintegrable, resonant or nonresonant, are discussed. It is pointed out that the standard stochastic averaging method and the stochastic averaging method of energy envelope are special cases of the stochastic averaging method of quasi-Hamiltonian systems and that the results obtained by this method for several examples prove its effectiveness. 展开更多
关键词 HAMILTONIAN system integrability STOCHASTIC EXCITATION STOCHASTIC AVERAGING diffusion process.
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INTEGRABILITY OF SECOND ORDER AUTONOMOUS SYSTEM 被引量:5
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作者 管克英 雷锦志 《Annals of Differential Equations》 2002年第2期117-135,共19页
The Liouville's integrability of the second order autonomous system is studied. It isproved that a second order polynomial system is Liouville integrable if and only if thereis an integral factor μ(x, y), such th... The Liouville's integrability of the second order autonomous system is studied. It isproved that a second order polynomial system is Liouville integrable if and only if thereis an integral factor μ(x, y), such that or a rational function in x and y. 展开更多
关键词 elementary transcendental function second order autonomous system integrability differential Galois theory
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Higher-dimensional integrable deformations of the modified KdV equation 被引量:1
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第7期15-21,共7页
The derivation of nonlinear integrable evolution partial differential equations in higher dimensions has always been the holy grail in the field of integrability.The well-known modified Kd V equation is a prototypical... The derivation of nonlinear integrable evolution partial differential equations in higher dimensions has always been the holy grail in the field of integrability.The well-known modified Kd V equation is a prototypical example of an integrable evolution equation in one spatial dimension.Do there exist integrable analogs of the modified Kd V equation in higher spatial dimensions?In what follows,we present a positive answer to this question.In particular,rewriting the(1+1)-dimensional integrable modified Kd V equation in conservation forms and adding deformation mappings during the process allows one to construct higher-dimensional integrable equations.Further,we illustrate this idea with examples from the modified Kd V hierarchy and also present the Lax pairs of these higher-dimensional integrable evolution equations. 展开更多
关键词 higher-dimensional integrable equation conservation form deformation mapping Lax integrability symmetry integrability
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函数连续性概念的历史:从欧拉到勒贝格 被引量:1
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作者 李亚亚 王昌 《自然辩证法通讯》 北大核心 2024年第2期61-67,共7页
函数是数学中的一个基本概念,连续性是函数的重要性质之一。函数连续性概念源于几何直观,受函数为解析表达式概念的限制,函数的连续性一开始被看成是解析法则的不变性。随着函数概念的发展,并顺应分析学严格化发展的潮流,柯西将连续意... 函数是数学中的一个基本概念,连续性是函数的重要性质之一。函数连续性概念源于几何直观,受函数为解析表达式概念的限制,函数的连续性一开始被看成是解析法则的不变性。随着函数概念的发展,并顺应分析学严格化发展的潮流,柯西将连续意味着不间断的几何观念用精确的分析学定义表述出来,从而给出了现代意义下的函数连续性,最终魏尔斯特拉斯给出了现行的ε-δ定义。对函数连续性概念演变过程的研究可以为反观分析学严格化历程提供一个窗口。 展开更多
关键词 分析学严格化 函数 连续性 可微性 可积性
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关于Abel方程可积性的一个新结果 被引量:7
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作者 冯录祥 魏列萍 《宝鸡文理学院学报(自然科学版)》 CAS 2001年第1期18-19,44,共3页
给出第一类 Abel方程一个新的可积条件 ,并由此得到 Riccati方程可积的几个充分条件。
关键词 ABEL方程 RICCATI方程 通积分 可积性 可积条件 常微分方程
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关于Riccati微分方程一个新的可积条件的注记 被引量:7
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作者 阎恩让 《宝鸡文理学院学报(自然科学版)》 CAS 2004年第3期179-180,共2页
分析了赵临龙1998年发表于《科学通报》上关于Riccati微分方程一个新的可积条件,举例说明了该条件是不成立的。指出了赵临龙文中论证的不足之处。
关键词 RICCATI微分方程 可积性 充分条件
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关于一类一阶非线性微分方程封闭可积条件的一个注记 被引量:7
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作者 冯录祥 《数学的实践与认识》 CSCD 北大核心 2003年第4期110-117,共8页
给出了一类一阶非线性微分方程y′=p( x) y +q( x) yμ +r( x) +∑ni =2fi( x) yi较为广泛的一个封闭可积条件 ,它推广和统一了文献 [1]中的定理 1和定理 2 ,特别指出近年来关于著名Riccati方程和
关键词 非线性微分方程 封闭可积条件 初等解 RICCATI方程 Abei方程
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INTEGRABILITY VIA INVARIANT ALGEBRAIC CURVES FOR PLANAR POLYNOMIALDIFFERENTIAL SYSTEMS 被引量:4
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作者 Colin Christopher (School of Mathematics and Statistics, University of Plymouth, Plymouth, Devon PL4 SAA, UNITED KINGDOM) Jaume Llibre (Dopartament de Matematiques, Universitat Autonoma de Barcelona, 08193-Bellaterra, Barcelona, SPAIN) 《Annals of Differential Equations》 2000年第1期5-19,共15页
We present an introduction to the Darboux integrability theory of planar complex and real polynomial differential systems containing some improvements to the classical theory.
关键词 integrability invariant algebraic curves planar polynomial differential systems
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CONVERGENCE OF WEIGHTED AVERAGES OF MARTINGALES IN NONCOMMUTATIVE BANACH FUNCTION SPACES 被引量:4
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作者 张超 侯友良 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期735-744,共10页
Let x (xn)≥1 be a martingale on a noncommutative probability space n (M, r) and (wn)n≥1 a sequence of positive numbers such that Wn = ∑ k=1^n wk →∞ as n →∞ We prove that x = (x.)n≥1 converges in E(M... Let x (xn)≥1 be a martingale on a noncommutative probability space n (M, r) and (wn)n≥1 a sequence of positive numbers such that Wn = ∑ k=1^n wk →∞ as n →∞ We prove that x = (x.)n≥1 converges in E(M) if and only if (σn(x)n≥1 converges in E(.hd), where E(A//) is a noncommutative rearrangement invariant Banach function space with the Fatou property and σn(x) is given by σn(x) = 1/Wn ∑k=1^n wkxk, n=1, 2, .If in addition, E(Ad) has absolutely continuous norm, then, (an(x))≥1 converges in E(.M) if and only if x = (Xn)n≥1 is uniformly integrable and its limit in measure topology x∞∈ E(M). 展开更多
关键词 Weighted average noncommutative martingales noncommutative BanachfunCtion spaces uniform integrability
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Conservation laws,Lie symmetries,self adjointness,and soliton solutions for the Selkov–Schnakenberg system
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作者 Kashif Ali Aly R Seadawy +1 位作者 Syed T R Rizvi Noor Aziz 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第2期29-44,共16页
In this article,we explore the famous Selkov–Schnakenberg(SS)system of coupled nonlinear partial differential equations(PDEs)for Lie symmetry analysis,self-adjointness,and conservation laws.Moreover,miscellaneous sol... In this article,we explore the famous Selkov–Schnakenberg(SS)system of coupled nonlinear partial differential equations(PDEs)for Lie symmetry analysis,self-adjointness,and conservation laws.Moreover,miscellaneous soliton solutions like dark,bright,periodic,rational,Jacobian elliptic function,Weierstrass elliptic function,and hyperbolic solutions of the SS system will be achieved by a well-known technique called sub-ordinary differential equations.All these results are displayed graphically by 3D,2D,and contour plots. 展开更多
关键词 Selkov-Schnakenberg system Lie symmetry analysis conservation laws adjointness integrability
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On power series statistical convergence and new uniform integrability of double sequences
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作者 Sevda Y■ld■z Kamil Demirci 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期519-532,共14页
In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p... In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings. 展开更多
关键词 power series methods statistical convergence uniform integrability double sequences
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Higher order Dirac structure and Nambu-Poisson geometry
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作者 Yanhui BI Jia LI 《Frontiers of Mathematics in China》 CSCD 2024年第1期37-56,共20页
This paper studies the properties of Nambu-Poisson geometry from the(n-l,k)-Dirac structure on a smooth manifold M.Firstly,we examine the automorphism group and infinitesimal on higher order Courant algebroid,to prove... This paper studies the properties of Nambu-Poisson geometry from the(n-l,k)-Dirac structure on a smooth manifold M.Firstly,we examine the automorphism group and infinitesimal on higher order Courant algebroid,to prove the integrability of infinitesimal Courant automorphism.Under the transversal smooth morphismΦ:N-→M and anchor mapping of M on(n-1,k)-Dirac structure,it's holds that the pullback(n-1,k)-Dirac structure on M turns out an(n-1,k)-Dirac structure on N.Then,given that the graph of Nambu-Poisson structure takes the form of(n-1,n-2)-Dirac structure,it follows that the single parameter variety of Nambu-Poisson structure is related to one variety closed n-symplectic form under gauge transformation.WhenΦ:N-→M is taken as the immersion mapping of(n-1)-cosymplectic submanifold,the pullback Nambu-Poisson structure on M turns out the Nambu-Poisson structure on N.Finally,we discuss the(n-1,O)-Dirac structure on M can be integrated into a problem of(n-1)-presymplectic groupoid.Under the mapping II:M-→M/H,the corresponding(n-1,O)-Dirac structure is F and E respectively.If E can be integrated into(n-1)-presymplectic groupoid(g,2),then there exists the only,such that the corresponding integral of F is(n-1)-presymplectic groupoid(g,). 展开更多
关键词 Nambu-Poisson structure n-symplectic structure (n-1 k)-Dirac structure integrability
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Derivatives of Intersection Local Time for Two Independent Symmetricα-stable Processes
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作者 Huan ZHOU Guang Jun SHEN Qian YU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第5期1273-1292,共20页
In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient cond... In this paper,we consider the derivatives of intersection local time for two independent d-dimensional symmetricα-stable processes X^(α) and X^(α)with respective indices α and α.We first study the sufficient condition for the existence of the derivatives,which makes us obtain the exponential integrability and H?lder continuity.Then we show that this condition is also necessary for the existence of derivatives of intersection local time at the origin.Moreover,we also study the power variation of the derivatives. 展开更多
关键词 Symmetric stable processes intersection local time exponential integrability power variation
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A Hierarchy of Lax Integrable Lattice Equations, Liouville Integrability and a NewIntegrable Symplectic Map 被引量:6
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作者 XUXi-Xiang ZHANGYu-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期321-328,共8页
A discrete matrix spectral problem and the associated hierarchy of Lax integrable lattice equations are presented, and it is shown that the resulting Lax integrable lattice equations are all Liouville integrable discr... A discrete matrix spectral problem and the associated hierarchy of Lax integrable lattice equations are presented, and it is shown that the resulting Lax integrable lattice equations are all Liouville integrable discrete Hamiltonian systems. A new integrable symplectic map is given by binary Bargmann constraint of the resulting hierarchy. Finally, an infinite set of conservation laws is given for the resulting hierarchy. 展开更多
关键词 lattice soliton equation discrete Hamiltonian system Liouville integrability NONLINEARIZATION symplctic map conservation law
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