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941.
Exotic interactions between solitons of the (2+1)-dimensional asymmetric Nizhnik-Novikov-Veselov system
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Starting from the extended tanh-function method (ETM) based on the
mapping method, the variable separation solutions of the
(2+1)-dimensional asymmetric Nizhnik--Novikov--Veselov (ANNV) system
are derived. By further study, we find that these variable separation
solutions are seemingly independent of but actually dependent on each
other. Based on the variable separation solution and by choosing
appropriate functions, some novel and interesting interactions
between special solitons, such as bell-like compacton, peakon-like
compacton and compacton-like semi-foldon, are investigated. 相似文献
942.
Discrete doubly periodic and solitary wave solutions for the semi-discrete coupled mKdV equations
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In this paper, the improved Jacobian elliptic function expansion
approach is extended and applied to constructing discrete solutions
of the semi-discrete coupled modified Korteweg de Vries (mKdV)
equations with the aid of the symbolic computation system Maple.
Some new discrete Jacobian doubly periodic solutions are obtained.
When the modulus $m \rightarrow 1$, these doubly periodic solutions
degenerate into the corresponding solitary wave solutions, including
kink-type, bell-type and other types of excitations. 相似文献
943.
By the application of the extended homogeneous balance
method, we derive an auto-Bäcklund transformation (BT) for
(2+1)-dimensional variable coefficient generalized KP equations. Based on
the BT, in which there are two homogeneity equations to be solved, we obtain
some exact solutions containing single solitary waves. 相似文献
944.
IntroductionRotor-bearings systems applied widely in industry are nonlinear dynamic systems of multi-degree-of-freedom.Synchronous vibration is its typical motion under unavoidable unbalance.Subharmonic,quasi-periodic and chaotic vibrations,caused by the … 相似文献
945.
Backlünd transformation and multiple soliton solutions for the (3+1)-dimensional Nizhnik-Novikov-Veselov equation
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We develop an approach to construct multiple soliton solutions of the (3+1)-dimensional nonlinear evolution equation. We take the (3+1)-dimensional Nizhnik-Novikov-Veselov (NNV) equation as an example. Using the extended homogeneous balance method, one can find a Backlünd transformation to decompose the (3+1)-dimensional NNV into a set of partial differential equations. Starting from these partial differential equations, some multiple soliton solutions for the (3+1)-dimensional NNV equation are obtained by introducing a class of formal solutions. 相似文献
946.
New infinite-dimensional hidden symmetries for the stationary axisymmetric Einstein-Maxwell equations with multiple Abelian gauge fields
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By proposing a so-called extended hyperbolic complex (EHC) function method, an Ernst-like (p+2)×(p+2) matrix EHC potential is introduced for the stationary axisymmetric (SAS) Einstein-Maxwell theory with p Abelian gauge fields (EM-p theory, for short), then the field equations of the SAS EM-p theory are written as a so-called Hauser-Ernst-like self-dual relation for the EHC matrix potential. Two Hauser-Ernst-type EHC linear systems are established, based on which some new parametrized symmetry transformations for the SAS EM-p theory are explicitly constructed. These hidden symmetries are found to constitute an infinite-dimensional Lie algebra, which is the semidirect product of the Kac-Moody algebra su(p+1,1)\otimes R(t,t^{-1}) and Virasoro algebra (without centre charges). All of the SAS EM-p theories for p=0,1,2,… are treated in a unified formulation, p=0 and p=1 correspond, respectively, to the vacuum gravity and the Einstein-Maxwell cases. 相似文献
947.
948.
ZHIHong-Yan LUZhuo-Sheng ZHANGHong-Qing 《理论物理通讯》2004,42(6):811-813
Based upon a further extended tanh method [Phys. Lett. A307 (2003) 269; Chaos, Solitons and Fractals 17 (2003) 669] and the symbolic computation system, Maple, we consider the (2 1)-dimensional dispersive long waveequations. We obtain many new solutions of the equation. These solutions contain solitomlike solutions, periodic form solutions, and some rational solutions. 相似文献
949.
Using the modified extended tanh-function method,
explicit and exact traveling wave solutions for the (2+1)-dimensional
higher-order Broer-Kaup (HBK) system, comprising new soliton-like and
period-form solutions, are obtained. 相似文献
950.
该文在对空圆柱层合壳(不充液)振动分析研究的基础上,借助线性势流理论,进一步考虑液固耦合效应,导出了敷有CLD贮液圆柱层合壳谐耦振的一阶常微分矩阵方程,该方程右边多了液动压力项.由于它不能预先给定,导致方程中出现未知项.为了克服这一困难,文中研究了液动压力的解式,并采用新型齐次扩容精细积分技术,提出了一种高效率和高精度的半解析半数值解法.进而还求解了CLD贮液圆柱容器在地面谐运动激励下的响应;通过大量数值计算分析了CLD的厚度、长度、敷设位置以及粘弹芯的复剪切模量对减振效果的影响.计算还表明了有液体的存在,这些影响和空容器时是不一样的.文中方法为CLD贮液容器的控制优化提供了有力手段. 相似文献