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1.
2.
A new(γA,σB)-matrix KP hierarchy with two time series γA and σB,which consists of γA-flow,σB-flow and mixed γA and σB-evolution equations of eigenfunctions,is proposed.The reduction and constrained flows of(γA,σB)matrix KP hierarchy are studied.The dressing method is generalized to the(γA,σB)-matrix KP hierarchy and some solutions are presented.  相似文献   

3.
Integrable Rosochatius deformations of finite-dimensional integrable systems are generalized to the soliton hierarchy with self-consistent sources. The integrable Rosochatius deformations of the Kaup-Newell hierarchy with self-consistent sources, of the TD hierarchy with self-consistent sources, and of the Jaulent-Miodek hierarchy with self- consistent sources, together with their Lax representations are presented.  相似文献   

4.
Integrable Rosochatius deformations of finite-dimensional integrable systems are generalized to the soliton hierarchy with self-consistent sources. The integrable Rosochatius deformations of the Kaup-Newell hierarchy with self-consistent sources, of the TD hierarchy with self-consistent sources, and of the Jaulent-Miodek hierarchy with self-consistent sources, together with their Lax representations are presented.  相似文献   

5.
Two hierarchies of new nonlinear differential-difference equations with one continuous variable and one discrete variable are constructed from the Darboux transformations of the Kaup–Newell hierarchy of equations. Their integrable properties such as recursion operator, zero-curvature representations, and bi-Hamiltonian structures are studied. In addition, the hierarchy of equations obtained by Wu and Geng is identified with the hierarchy of two-component modified Volterra lattice equations.  相似文献   

6.
We have found two types of important exact solutions,compacton solutions,which are solitary waves with the property that after colliding with their own kind,they re-emerge with the same coherent shape very much as the solitons do during a completely elastic interaction,in the (1 1)D,(1 2)D and even (1 3)D models,and dromion solutions (exponentially decaying solutions in all direction) in many (1 2)D and (1 3)D models.In this paper,symmetry reductions in (1 2)D are considered for the break soliton-type equation with fully nonlinear dispersion (called BS(m,n) equation)ut b(u^m)xxy 4b(u^n δx^-1uy)x=0,which is a generalized model of (1 2)D break soliton equation ut buxxy 4buuy 4buxδx^-1uy=0,by using the extended direct reduction method.As a result,six types of symmetry reductions are obtained.Starting from the reduction equations and some simple transformations,we obtain the solitary wavke solutions of BS(1,n) equations,compacton solutions of BS(m,m-1) equations and the compacton-like solution of the potential form (called PBS(3,2)) ωxt b(ux^m)xxy 4b(ωx^nωy)x=0.In addition,we show that the variable ∫^x uy dx admits dromion solutions rather than the field u itself in BS(1,n) equation.  相似文献   

7.
We introduce Frobenius algebra ?-valued (n, m)th KdV hierarchy and construct its bi-Hamiltonian structures by employing ?-valued pseudo-differential operators. As an illustrative example, the (1, 1)th -valued case is analyzed in detail. Its Hamiltonian structures and recursion operator are derived. Infinitely many symmetries, conservation laws and explicit flow equations are also obtained.  相似文献   

8.
A difference Ha-miltonian operator with three arbitrary constants is presented. When the arbitrary constants -in the Hamiltonian operator are suitably chosen, a pair of Hamiltonian operators are given. The resulting Hamiltonian pair yields a difference hereditary operator. Using Magri scheme of bi-Hamiltonian formulation, a hierarchy of the generalized Toda lattice equations is constructed. Finally, the discrete zero curvature representation is given for the resulting hierarchy.  相似文献   

9.
A difference Hamiltonian operator with three arbitrary constants is presented. When the arbitrary constants in the Hamiltonian operator are suitably chosen, a pair of Hamiltonian operators are given. The resulting Hamiltonian pair yields a difference hereditary operator. Using Magri scheme of bi-Hamiltonian formulations a hierarchy of the generalized Toda lattice equations is constructed. Finally, the discrete zero curvature representation is given for the resulting hierarchy.  相似文献   

10.
A new and efficient way is presented for discrete integrable couplings with the help of two semi-direct sum Lie algebras. As its applications, two discrete integrable couplings associated with the lattice equation are worked out. The approach can be used to study other discrete integrable couplings of the discrete hierarchies of solition equations.  相似文献   

11.
A new simple loop algebra GM is constructed, which is devoted to establishing an isospectral problem.By making use of generalized Tu scheme, the multi-component SC hierarchy is obtained. Furthermore, an expanding loop algebra FM of the loop algebra GM is presented. Based on FM, the multi-component integrable coupling system of the multi-component SC hierarchy of soliton equations is worked out. How to design isospectral problem of mulitcomponent hierarchy of soliton equations is a technique and interesting topic. The method can be applied to other nonlinear evolution equations hierarchy.  相似文献   

12.
In this paper, we first obtain a bilinear form with small perturbation u_0 for a generalized(3+1)-dimensional nonlinear wave equation in liquid with gas bubbles. Based on that, a new bilinear B?cklund transformation which consists of four bilinear equations and involves seven arbitrary parameters is constructed. After that, by applying a new symbolic computation method, we construct the higher order rogue waves with controllable center to the generalized(3+1)-dimensional nonlinear wave equation. The rogue waves present new structure, which contain two free parametersα and β. The dynamic properties of the higher order rogue waves are demonstrated graphically. The graphs tell that the parameters α and β can control the center of the rogue waves.  相似文献   

13.
樊胜  阎芳  张鸿洲  赵志祥 《中国物理 C》2003,27(11):1009-1014
基于核反应蒸发模型和预平衡激子模型,在一些近似条件下得到了入射能量小于20MeV的(n,p)的激发函数解析半经验表达式,靶核在23≤A≤209的范围内,利用大量(n,p)反应的截面实验数据对可调参数进行了研究,得到了参数对靶核的N和Z以及中子入射能量的依赖关系,对得到的参数做了定性的解释,利用普适参数对(n,p)反应的激发函数做了预言,预言值在其误差范围内与实验数据一致。  相似文献   

14.
Searching for special solitary wave solutions with compact support is of important significance in soliton theory. In this paper, to understand the role of nonlinear dispersion in pattern formation, a family of the regularized longwave Boussincsq equations with fully nonlinear dispersion (simply called R(m, n) equations), utt + a( un )xx + b(um )xxtt = 0(a, b const.), is studied. New solitary wave solutions with compact support of R(m, n) equations are found. In addition we find another compacton solutions of the two special cases, R(2, 2) equation and R(3, 3) equation. It is found that the nonlinear dispersion term in a nonlinear evolution equation is not a necessary condition of that it possesses compacton solutions.  相似文献   

15.
In this paper, the generalized tanh function method is extended to (2 1)-dimensional canonical generalized KP (CGKP) equation with variable coefficients. Taking advantage of the Riccati equation, many explicit exact solutions,which contain multiple soliton-like and periodic solutions, are obtained for the (2 1)-dimensional CGKP equation with variable coefficients.  相似文献   

16.
In this paper, the generalized ranch function method is extended to (2+1)-dimensianal canonical generalized KP (CGKP) equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit exact solutions, which contain multiple soliton-like and periodic solutions, are obtained for the (2+1)-dimensional OGKP equation with variable coetffcients.  相似文献   

17.
采用密度泛函理论中的广义梯度近似对C60(CF3)n (n=2,4,6,10)几何结构和电子性质的变化规律进行了计算研究.发现在C60(CF3)4可能稳定存在的三种同分异构体中,具有p-p-p加成方式的衍生物热力学性质最为稳定;在C60(CF3)6可能稳定存在的三种同分异构体中,具有p-p-p-m-p加成方式的衍生物热力学性质最为稳定.对C60(CF3)2,C60(CF3)4,C60(CF3)6和C60(CF3)10四种加成衍生物的几何结构分析可知:随着CF3加成个数的增加,C60中的C-C平均键长逐渐变大,笼子与CF3之间连接键CC60-CCF3逐渐变大.对它们的电子结构分析可知,随着CF3加成数目的增多,反应热几乎是线性增加.而C60(CF3)n(n=2,4,6,10)分子的平均反应热在n=6处为极大值,说明C60(CF3)6应该是最容易得到的加成产物.由Mulliken电荷可知,加成的CF3个数越多,CF3与笼子的相互作用也就越强,每个CF3转移到笼子上电荷数也就越多.C60(CF3)n的自旋聚居数分布表明它们均为闭壳层结构.最后,从CF3对分子的前线轨道贡献可知,四种分子的得电子情况和失电子情况均发生在碳笼本身,并不随着CF3个数的增加而发生明显的改变.  相似文献   

18.
In this paper, a discrete KdV equation that is related to the famous continuous KdV equation is studied. First, an integrable discrete KdV hierarchy is constructed, from which several new discrete KdV equations are obtained. Second, we correspond the first several discrete equations of this hierarchy to the continuous KdV equation through the continuous limit. Third, the generalized (m, 2Nm)-fold Darboux transformation of the discrete KdV equation is established based on its known Lax pair. Finally, the diverse exact solutions including soliton solutions, rational solutions and mixed solutions on non-zero seed background are obtained by applying the resulting Darboux transformation, and their asymptotic states and physical properties such as amplitude, velocity, phase and energy are analyzed. At the same time, some soliton solutions are numerically simulated to show their dynamic behaviors. The properties and results obtained in this paper may be helpful to understand some physical phenomena described by KdV equations.  相似文献   

19.
采用符合方法,测量级联γ放射源60Co在光电倍增管(PMT)光阴极窗上激发产生的切伦科夫光,从而测定PMT渡越时间涨落. 用泊松加高斯卷积方法获得单(多)光电子峰位,处理不同光电子数的~PMT~渡越时间涨落.测试XP2020和透紫XP2020Q PMT结果显示, 测量的渡越时间与菲利浦公司给出的指标一致, 渡越时间涨落与光电子数满足平方根反比关系. 该方法对可分辨单(多)光电子峰的~PMT~是可行的.  相似文献   

20.
The generalized nonlinear Schrdinger equation with parabolic law nonlinearity is studied by using the factorization technique and the method of dynamical systems.From a dynamic point of view,the existence of smooth solitary wave,kink and anti-kink wave is proved and the sufficient conditions to guarantee the existence of the above solutions in different regions of the parametric space are given.Also,all possible explicit exact parametric representations of the waves are presented.  相似文献   

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