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81.
82.
Sergey P. Kuznetsov 《Physica D: Nonlinear Phenomena》2007,232(2):87-102
We propose several examples of smooth low-order autonomous dynamical systems which have apparently uniformly hyperbolic attractors. The general idea is based on the use of coupled self-sustained oscillators where, due to certain amplitude nonlinearities, successive epochs of damped and excited oscillations alternate. Because of additional, phase sensitive coupling terms in the equations, the transfer of excitation from one oscillator to another is accompanied by a phase transformation corresponding to some chaotic map (in particular, an expanding circle map or Anosov map of a torus). The first example we construct is a minimal model possessing an attractor of the Smale-Williams type. It is a four-dimensional system composed of two oscillators. The underlying amplitude equations are similar to those of the predator-pray model. The other three examples are systems of three coupled oscillators with a heteroclinic cycle. This scheme presents more variability for the phase manipulations: in the six-dimensional system not only the Smale-Williams attractor, but also an attractor with Arnold cat map dynamics near a two-dimensional toral surface, and a hyperchaotic attractor with two positive Lyapunov exponents, are realized. 相似文献
83.
84.
The stability and convergence rate of coupled atomistic-continuum methods are studied analytically and numerically. These methods couple a continuum model with molecular dynamics through the exchange of boundary conditions in the continuum-particle overlapping region. Different coupling schemes, including velocity–velocity, flux–velocity, velocity–flux and flux–flux, are studied. It is found that the velocity–velocity and flux–velocity schemes are stable. The flux–flux scheme is weakly unstable. The stability of the velocity–flux scheme depends on the parameter Tc which is the length of the time interval between successive exchange of boundary conditions. It is stable when Tc is small and unstable when Tc is large. For steady-state problems, the flux–velocity scheme converges faster than the other coupling schemes. 相似文献
85.
A simple method is proposed leading to reasonable approximations of the partition function of Morse oscillators in terms of
elementary functions. 相似文献
86.
Jin Liang 《Nonlinear Analysis: Theory, Methods & Applications》2009,71(12):e359
This paper is concerned with delay coupled systems of parabolic equations with nonlocal and nonlinear boundary conditions. For them, a new and general comparison principle is established, which is more general and useful than the existing results. 相似文献
87.
A common two-mode squeezed state is one of the most important resources in quantum information processing of continuous variables.
In this paper, a two-mode squeezed rotation-entangled state is obtained in coupled mesoscopic circuits. It is shown that instantaneously
switching on the external sources may result in a two-mode squeezed state of the system, which actually arises from the coupling
effect. The entanglement of the squeezed rotation-entangled state is studied. The degree of entanglement for coupled mesoscoipc
circuit was calculated by using the technique of integration within an ordered product of operators. It is shown that the
entanglement of the two-mode squeezed rotation-entangled state is different from that of the common squeezed state, for example,
the degree of entanglement of the system, which is in the squeezed state, exist maximum value at a very low temperature. 相似文献
88.
The coupled task problem is to schedule n jobs, each one consisting of two subtasks with exact delay times between them, on a single machine. We derive a new lower bound for the problem variant with unit execution times and correct a previously published analysis. 相似文献
89.
多光束全息互连元件往往需要大量的耦合波方程才能描述。本文通过分析记录时生成的互调制光栅的性质及其对衍射的影响,对问题进行适当的简化。通过解不同条件下的耦合波方程、分别给出了多光束全息图在各种不同情况下的衍射效率的近似解析表达式,展示了衍射效率与各实验参量之间的关系。为进一步研究多光束全息互连元件的性质、比较各种条件下的效率以及各参量对总体效率的影响,提供了方便。 相似文献
90.