Exact traveling wave solutions in the coupled plane-base rotator model of DNA

The internal dynamics of the DNA base pairs is studied starting from the generalized coupled plane base-rotator model of DNA, obtained by Yomosa and later improved by Takeno and Homma. We conceive the double-stranded DNA as an anisotropically coupled spin chain simple model. The generalized Hamiltonian expressed in terms of quasi-spin operators is averaged over the generalized coherent states in the Perelomov sense, in order to obtain the classical non-linear evolution equations of this molecular system where the inhomogeneity has not been considered. This approach provides the equations of motion, which could be reduced to a nonlinear Schrödinger equation with a saturable nonlinearity. This non-linear equation, under certain restrictions in the parametric space, supports traveling periodic triangular, bell, bubble and kink like solutions.     

Existence of traveling wave solutions for a nonlinear dissipative-dispersive equation

In this paper, we consider a dissipative-dispersive nonlinear equation appliable to many physical phenomena. Using the geometric singular perturbation method based on the theory of dynamical systems, we investigate the existence of its traveling wave solutions with the dissipative terms having sufficiently small coefficients. The results show that the traveling waves exist on a two-dimensional slow manifold in a three-dimensional system of ordinary differential equations （ODEs）. Then, we use the Melnikov method to establish the existence of a homoclinic orbit in this manifold corresponding to a solitary wave solution of the equation. Furthermore, we present some numerical computations to show the approximations of such wave orbits.     

Bifurcations of travelling wave solutions for a coupled nonlinear wave system

Introduction FangShaomeiandGuoBoling[1]consideredthefollowingtimeperiodicproblemof dampedcouplednonlinearwaveequations:ut f(u)x-αuxx βuxxx 2vvx=G1(u,v) h1(x),vt-γvxx 2(uv)x g(v)x=G2(u,v) h2(x),(1)whereα,β,γareconstants,andγ>0,β≠0.Undertheperiodicboundaryconditions,the authorsobtainedtheuniqueexistenceofstrongsolutionsfortheabovesystem.InthispaperweshallconsiderbifurcationbehaviorofthetravellingwavesolutionsofEq.(1)inthecaseGi(u,v)≡0,hi(u,v)≡0(i=1,2).Letξ=x-ct,u=u(x-ct),where cis…     

Existence of periodic traveling wave solutions for a class of generalized BBM equation

In this paper, a new kind of generalized BBM equation is introduced and discussed. Some existence theorems of periodic traveling wave solutions for this kind generalized BBM equation are given.     

A reaction-diffusion equation and its traveling wave solutions

In the present paper, we study a non-linear reaction-diffusion equation, which can be considered as a generalized Fisher equation. An exact solution and traveling wave solutions to the generalized Fisher equation are obtained by means of the Cole-Hopf transformation and the Lie symmetry method.     

Spatiotemporal and synchronous chaos in accumulated coupled map lattice

The onset of spatiotemporal chaos in coupled map lattice (CML) with a new coupling scheme called accumulated CML is studied in this paper. A rigorous proof of the existence of chaos in the sense of Li–Yorke is presented. Also the range of the coupling strength in which global synchronization can be obtained is calculated by stability analysis of the synchronized state. Finally, the positivity of Lyapunov exponents confirms the existence of chaos.     

Periodic solutions in one-dimensional coupled map lattices

IntroductionDynamicsofcoupledmaplattices (CML )haverecentlyattractedconsiderableattention[1- 4].IthasbeenfoundthatCMLsexhibitavarietyofspace_timepatterns:space_timeintermittency ,spatiotemporalchaos,frontsandinterfaces,nonlinearperiodicsolutions.Inthispaper,anone_dimensionalinfinitechainofnonlinearcoupledmapsisconsideredandtheexistenceofperiodicsolutionsisprovedwhenthecouplingstrengthαissmallenough .Ourapproachistheanti_integrablelimitintroducedinRefs.[5-7] .Intheanti_integrablelimit(coup…     

Two types of traveling wave solutions to burgers-KdV equations

ＩｎｔｒｏｄｕｃｔｉｏｎＳｏｃａｌｌｅｄＢｕｒｇｅｒｓ＿ＫｄＶｅｑｕａｔｉｏｎｓａｒｅｔｈｅｆｏｌｌｏｗｉｎｇｎｏｎｌｉｎｅａｒｅｖｏｌｕｔｉｏｎｅｑｕａｔｉｏｎｓｕｔ ｕｕｘ-αｕｘｘ βｕｘｘｘ =0 ,(1 )ｗｈｉｃｈｗａｓｍａｔｈｅｍａｔｉｃａｌｍｏｄｅｌｉｎｔｒｏｄｕｃｅｄｗｈｅｎｏｎｅｓｔｕｄｉｅｄｓｏｍｅｐｈｙｓｉｃａｌｐｒｏｂｌｅｍｓｓｕｃｈａｓｌｉｑｕｉｄｆｌｏｗｓｗｉｔｈａｉｒｂｕｂｂｌｅｓ,ｔｈｅｆｌｕｉｄｉｎｔｈｅｅｌａｓｔｉｃｔｕｂｅｓａｎｄｓｏｏｎ ,ｗｈｅｒｅαａｎｄβｓｔａｎ…     

Exact traveling wave solutions to 2D-generalized Benney-Luke equation

By using the dynamical system method to study the 2D-generalized Benney- Luke equation, the existence of kink wave solutions and uncountably infinite many smooth periodic wave solutions is shown. Explicit exact parametric representations for solutions of kink wave, periodic wave and unbounded traveling wave are obtained.     

Control and synchronization of Mandelbrot sets in coupled map lattice

This paper gives the definition of Mandelbrot set in a coupled map lattice (CML Mandelbrot set), and studies its control and synchronization. A proper mathematical transform is used to achieve the scaling, with regards to size, of the CML Mandelbrot set without changing its structure properties. Furthermore, two different methods, gradient control and optimal control, are separately applied to realize the synchronization of different CML Mandelbrot sets, that making one CML Mandelbrot set change into another. Numerical simulations show the effectiveness of these controls and the feasibility of achieving synchronization using the two different methods.     

New explicit and exact traveling wave solutions for two nonlinear evolution equations

In this paper, with the aid of computer symbolic computation system such as Maple, an algebraic method is firstly applied to two nonlinear evolution equations, namely, nonlinear Schrodinger equation and Pochhammer–Chree (PC) equation. As a consequence, some new types of exact traveling wave solutions are obtained, which include bell and kink profile solitary wave solutions, triangular periodic wave solutions, and singular solutions. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in mathematical physics.     

A novel block cryptosystem based on the coupled chaotic map lattice

In this paper, the authors propose a novel block cryptographic scheme based on the coupled chaotic map lattice. A pseudorandom number generator is constructed with the coupled spatiotemporal chaotic map lattice, which depends on the plaintext. The plaintext block is then encrypted by the classical chaotic masking technique. The pseudorandom sequences produced by the generator have excellent statistical properties; therefore, they are suitable for encrypting messages. Moreover, it can be easily implemented in parallel by hardware. Both theoretical analysis and numerical simulation prove the block cryptographic scheme secure and practical.     

Existence of time periodic solutions for a damped generalized coupled nonlinear wave equations

IntroductionInRef.[1 ] ,theauthorsestablishedtheuniqueexistenceofthesmoothsolutionforthefollowingcouplednonlinearequationsut=uxxx+buux+ 2vvx, (1 )vt=2 (uv) x. (2 )Thesewereproposedtodescribetheinteractionprocessofinternallongwaves.InRef.[2 ] ,ItoM .proposedarecursionoperatorbywhichheinferredthatEqs.(1 )and (2 )possesinfinitelymanysymmetriesandconstantsofmotion .InRef.[3 ] ,P .F .HeestablishedtheexistenceofasmoothsolutiontothesystemofcouplednonlinearKdVequation[4 ]ut=a(uxxx+buux) + 2bvvx,(…     

Dynamical behavior of traveling wave solutions of ion acoustic plasma equations

By using the theory of planar dynamical systems to the ion acoustic plasma equations, we obtain the existence of the solutions of the smooth and non-smooth solitary waves and the uncountably infinite smooth and non-smooth periodic waves. Under the given parametric conditions, we present the sufficient conditions to guarantee the existence of the above solutions.     

A novel pseudo-random number generator from coupled map lattice with time-varying delay

Chaos has been widely combined with cryptography in the field of information security, especially, a considerable amount of studies of generating pseudo-random numbers based on chaotic systems have been proposed in recent decades. However, many of them are easy to be attacked via utilizing the nonlinear prediction method based on phase space reconstruction and other analysis. Furthermore, under the finite precision environment of computer simulation, there does not exist a random sequence which is truly non-periodic. Unfortunately, few researches had made a related analysis on the above two discussions. This paper is devoted to designing a pseudo-random number generator based on coupled map lattice with time-varying delay, analyzing the random properties of the generated pseudo-random numbers and discussing the dynamical degradation of the system under finite precision of computer simulation. The proposed scheme merely depends on the determining equation; thus, the algorithm itself is not complex, which does not impose high demand on computer hardware and its efficiency is excellent. In order to meet the requirements of using the proposed pseudo-random number generator in cryptography and other practical engineering applications, the proposed pseudo-random number generator is subjected to statistical tests utilizing the well-known test suites, such as NIST SP800-22 and TestU01. Moreover, other related properties, such as permutation entropy, invariant distribution, degradation of dynamical characteristics and parameter test, are also investigated. All results illustrate that the new pseudo-random number generator can generate a high percentage of available pseudo-random numbers for scientific computer simulation and practical applications in the field of information security.     

Dynamics of localized wave solutions for the coupled Higgs field equation

Nonlinear Dynamics - By virtue of Hirota bilinear form of the coupled Higgs field equation, some higher-order rogue wave, the Ma breather, the Akhmediev breather and the general breather solutions...