共查询到20条相似文献,搜索用时 31 毫秒
1.
Folded Solitary Waves and Foldons in (2+1) Dimensions 总被引:2,自引:0,他引:2
TANGXiao-Yan LOUSen-Yue 《理论物理通讯》2003,40(1):62-66
A general type of local/zed excitations, folded solitary waves and foldons, is defined and studied both analytically and graphically. The folded solitary waves and foldons may be “folded“ in quite complicated ways and possess qnite rich structures and abundant interaction properties. The folded phenomenon is quite universal in the real natural world. The folded solitary waves and foldons are obtained from a quite universal formula and the universal formul is valid for some quite universal (2 1)-dimensional physical mode/s. The “universal“ formula is also extended to a more general form with many more independent arbitrary functions. 相似文献
2.
Starting from a quite universal formula, which is
obtained by variable separation approach and valid for many
(2+1)-dimensional nonlinear physical models, a new general type of solitary
wave, i.e., semifolded solitary waves (SFSWs) and semifoldons, is defined
and studied. We investigate the behaviors of the interactions for the new
semifolded localized structures both analytically and graphically. Some
novel features or interesting behaviors are revealed. 相似文献
3.
Considering that folded phenomena are rather universal in nature and some arbitrary functions can be included in the exact excitations of many (2+1)-dimensional soliton systems, we use adequate multivalued functions to construct folded solitary structures in multi-dimensions. Based on some interesting variable separation results in the literature, a common formula with arbitrary functions has been derived for suitable physical quantities of some significant (2+1)-dimensional soliton systems like the generalized Ablowitz-Kaup-Newell-Segur (GAKNS) model, the generalized Nizhnik-Novikov-Veselov (GNNV) system and the new (2+1)-dimensional long dispersive wave (NLDW) system. Then a new special type of two-dimensional solitary wave structure, i.e. the folded solitary wave and foldon, is obtained. The novel structure exhibits interesting features not found in the single valued solitary excitations. 相似文献
4.
A general solution, including three arbitrary functions, is obtained
for a (2+1)-dimensional modified dispersive water-wave (MDWW)
equation by means of the WTC truncation method. Introducing proper
multiple valued functions and Jacobi elliptic functions in the seed
solution, special types of periodic folded waves are derived. In the
long wave limit these periodic folded wave patterns may degenerate
into single localized folded solitary wave excitations. The
interactions of the periodic folded waves and the degenerated
single folded solitary waves are investigated graphically and found
to be completely elastic. 相似文献
5.
HUANG Wen-Hua 《理论物理通讯》2008,50(4):827-831
A general solution including three arbitrary functions is obtained for the (2+1)-dimensional higher-order Broer-Kaup equation by means of WTC truncation method. Introducing proper multiple valued functions and Jacobi elliptic functions in the seed solution, special types of periodic folded waves are derived. In long wave limit these periodic folded
wave patterns may degenerate into single localized folded
solitary wave excitations. The interactions of the periodic
folded waves and their degenerated single folded solitary waves
are investigated graphically and are found to be completely elastic. 相似文献
6.
Considering that the multi-valued (folded) localized excitations may appear in many (2 1)-dimensional soliton equations because some arbitrary functions can be included in the exact solutions, we use some special types of muliti-valued functions to construct folded solitrary waves and foldons in the (2 1)-dimensional Broer-Kaup equation.These folded excitations are invesigated both analytically and graphically in an alternative way. 相似文献
7.
ZHANGJie-Fang HUANGWen-Hua 《理论物理通讯》2003,40(5):533-536
Considering that the multi-valued (folded) localized excitations may appear in many (2 1)-dimensional soliton equations because some arbitrary functions can be included in the exact solutions, we use some special types of muliti-valued functions to construct folded solitrary waves and foldons in the (2 1)-dimensional Broer-Kaup equation.These folded excitations are invesigated both analytically and graphically in an alternative way. 相似文献
8.
Starting from the standard truncated Painlevé
expansion and a multilinear variable separation approach, a quite general
variable separation solution of the (2+1)-dimensional (M+N)-component AKNS
(Ablowitz–Kaup–Newell–Segur) system is derived. In addition to the
single-valued localized coherent soliton excitations like dromions,
breathers, instantons, peakons, and a previously revealed chaotic localized
solution, a new type of multi-valued (folded) localized excitation is
obtained by introducing some appropriate lower-dimensional multiple valued
functions. The folded phenomenon is quite universal in the real natural
world and possesses quite rich structures and abundant interaction
properties. 相似文献
9.
In this paper, the interactions of three types of adjacent combined solitary waves, which are conveniently called Types I, II, and III combined solitary wave, respectively, are numerically investigated. The results show that their interactions exhibit quite different properties. For Type I combined solitary waves, the interaction is quite weaker than that of dark solitons for the standard nonlinear Schrödinger (NLS) equation. Interestingly, the interaction can be well suppressed when they are reduced to the pure dark ones. But for Type II combined solitary waves, the interaction is much stronger than those of Types I and III combined solitary waves and is very difficult to be suppressed. Surprisingly, two adjacent Type III combined solitary waves, both brightlike and darklike ones, hardly interplay each other. These results imply that Type I pure dark solitary waves and Type III combined solitary waves may be regarded as appropriate candidates for information carriers. In addition, the propagation of pulse trains composed of combined solitary waves is investigated. 相似文献
10.
在(1 1)维非线性动力学系统,人们发现不同的局域激发模式分别存在于不同的非线性系统.可是最近的若干研究表明,在高维非线性动力学系统中,如果选取适当的边值条件或初始条件时,人们可以同时找到若干不同的局域激发模式,如:紧致子、峰孤子、呼吸子和折叠子等.本文的主要目的是寻找(1 1)维非线性耦合Ito系统中的不同的局域激发模式.首先,基于一个特殊的Painlev-éBacklund变换和线性变量分离方法,求得了该系统具有若干任意函数的变量分离严格解.然后,根据得到的变量分离严格解,通过选择严格解中的任意函数,引入恰当的单值分段连续函数和多值局域函数,成功找到了耦合Ito系统若干有实际物理意义的单值和多值局域激发模式,如:峰孤子,紧致子和多圈孤子等. 相似文献
11.
A.A. Mamun 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,11(1):143-147
An investigation has been made of ion-acoustic solitary waves in an unmagnetized nonthermal plasma whose constituents are
an inertial ion fluid and nonthermally distributed electrons. The properties of stationary solitary structures are briefly
studied by the pseudo-potential approach, which is valid for arbitrary amplitude waves, and by the reductive perturbation
method which is valid for small but finite amplitude limit. The time evolution of both compressive and rarefactive solitary
waves, which are found to coexist in this nonthermal plasma model, is also examined by solving numerically the full set of
fluid equations. The temporal behaviour of positive (compressive) solitary waves is found to be typical, i.e., the positive initial disturbance breaks up into a series of solitary waves with the largest in front. However, the behaviour
of negative (rarefactive) solitary waves is quite different. These waves appear to be unstable and produce positive solitary
waves at a later time. The relevancy of this investigation to observations in the magnetosphere of density depressions is
briefly pointed out.
Received 12 October 1999 相似文献
12.
By means of extended homogeneous balance method and variable
separation approach, quite a general variable separation solution
of the (2+1)-dimensional Broer-Kaup-Kupershmidt equation is
derived. From the variable separation solution and by selecting
appropriate functions, a new class of (2+1)-dimensional
nonpropagating solitary waves are found. The novel features
exhibited by these new structures are first revealed. 相似文献
13.
Dust ion-acoustic solitary waves in unmagnetized quantum plasmas are studied in spherical and cylindrical geometries. Using quantum hydrodynamic model, the electrostatic waves are investigated in the weakly nonlinear limit. A deformed Korteweg-de Vries (dKdV) equation is derived by using the reductive perturbation method and its numerical solutions are also presented. The quantum diffraction and quantum statistical effects incorporated in the system modifies the characteristics of dust ion-acoustic waves in cylindrical and spherical geometries. The role of stationary dust particles in quantum plasmas are also discussed. It is shown that the cylindrical and spherical dust ion-acoustic solitary waves behave quite differently from one-dimensional planar solitary waves in quantum plasmas. 相似文献
14.
It is known that weak interactions of two solitary waves in generalized nonlinear Schrödinger (NLS) equations exhibit fractal dependence on initial conditions, and the dynamics of these interactions is governed by a universal two-degree-of-freedom ODE system [Y. Zhu J. Yang, Universal fractal structures in the weak interaction of solitary waves in generalized nonlinear Schrödinger equations, Phys. Rev. E 75 (2007) 036605]. In this paper, this ODE system is analyzed comprehensively. Using asymptotic methods along separatrix orbits, a simple second-order map is derived. This map does not have any free parameters after variable rescalings, and thus is universal for all weak interactions of solitary waves in generalized NLS equations. Comparison between this map’s predictions and direct simulations of the ODE system shows that the map can capture the fractal-scattering phenomenon of the ODE system very well both qualitatively and quantitatively. 相似文献
15.
Bridges TJ 《Physical review letters》2000,84(12):2614-2617
Transverse instabilities correspond to a class of perturbations traveling in a direction transverse to the direction of the basic solitary wave. Solitary waves traveling in one space direction generally come in one-parameter families. We embed them in a two-parameter family and deduce a new geometric condition for transverse instability of solitary waves. This condition is universal in the sense that it does not require explicit properties of the solitary wave-or the governing equation. In this paper the basic idea is presented and applied to the Zakharov-Kuznetsov equation for illustration. An indication of how the theory applies to a large class of equations in physics and oceanography is also discussed. 相似文献
16.
O. Weis 《Zeitschrift für Physik B Condensed Matter》1975,21(1):1-10
The generation of hypersound at a free surface of a piezoelectric crystal by means of an incident plane electromagnetic wave is considered and the corresponding boundary problem is discussed in detail. The formula developed in this paper are quite general and can be applied to any piezoelectric crystal and any face orientation. As an important example, the excitation of sound waves at several quartz faces is treated numerically and the results are presented in diagrams showing directly the power conversion from the plane incident electromagnetic wave into the sound waves as function of the angle of incidence and of polarization directions. 相似文献
17.
I. B. Bakholdin A. A. Zharkov A. T. Il’ichev 《Journal of Experimental and Theoretical Physics》2000,91(1):111-125
Soliton-type solutions of the complete unreduced system of transport equations describing the plane-parallel motions of an isotropic collisionless quasineutral plasma in a magnetic field with constant ion and electron temperatures are studied. The regions of the physical parameters for fast and slow magnetosonic branches, where solitons and generalized solitary waves—nonlocal soliton structures in the form of a soliton “core” with asymptotic behavior at infinity in the form of a periodic low-amplitude wave—exist, are determined. In the range of parameters where solitons are replaced by generalized solitary waves, soliton-like disturbances are subjected to decay whose mechanisms are qualitatively different for slow and fast magnetosonic waves. A specific feature of the decay of such disturbances for fast magnetosonic waves is that the energy of the disturbance decreases primarily as a result of the quasistationary emission of a resonant periodic wave of the same nature. Similar disturbances in the form of a soliton core of a slow magnetosonic generalized solitary wave essentially do not emit resonant modes on the Alfvén branch but they lose energy quite rapidly because of continuous emission of a slow magnetosonic wave. Possible types of shocks which are formed by two types of existing soliton solutions (solitons and generalized solitary waves) are examined in the context of such solutions. 相似文献
18.
HUANG Shou-Jun CHEN Chun-Li 《理论物理通讯》2007,48(5):773-780
In this paper, we employ the bifurcation method of dynamical systems to study the solitary waves and periodic waves of a generalized Boussinesq equations. All possible phase portraits in the parameter plane for the travelling wave systems are obtained. The possible solitary wave solutions, periodic wave solutions and cusp waves for the general Boussinesq type fluid model are also investigated. 相似文献
19.
We show by using the real exponential approach that the d-dimensional discrete modified KdV equation has more general exact solitary wave solutions than the known bright soliton and kink solutions. Depending on the values of the parameters, the new solutions can describe both bright and dark solitary waves. 相似文献
20.
依据近场波数积分、远场耦合简正波相结合的二维噪声场模型,侧重理论研究孤子内波所在扇区,环境噪声垂直阵响应的变化,分析了某些孤子内波情形下垂直阵环境噪声水平凹槽变深这一异常现象的原因:孤子内波离垂直阵较近时,远离内波的海面噪声源多,其激发的简正波能量由低号耦合到高号,在垂直阵处高号简正波能量对环境噪声场贡献增大,导致环境噪声水平凹槽加深;对于大尺度、多波包孤子内波,其范围相对较大,内波所在区的局部简正波本征值和本征函数产生的变化影响显著,使低号简正波衰减变快,而高号衰减慢,导致接收阵处高号简正波能量增加,低号简正波变弱,这样,无论孤子内波群靠近或离接收阵远,都将使垂直阵环境噪声水平凹槽加深。 相似文献