具有随机色散的光时分复用系统中色散管理孤子相互作用(英文)

本文采用变分法和数值方法研究了具有随机色散的光时分复用系统中色散管理孤子相互作用.发现随机色散增强了孤子间相互作用,产生了导致孤子淹没的振幅和间隔涨落.相互作用距离与初始间隔、初始相对相位、脉宽和初始相对振幅有关.

随机色散对孤子传输系统时间抖动影响(英文)

在分布放大传输系统中建立了随机色散模型，利用自伴算符法研究了随机色散的影响． 结果表明：随机色散与放大的自发辐射噪音联合作用增大了传输系统的时间抖动，其中与传输距离有关的随机色散具有长距离效应，而与孤子频移有关的随机色散具有短距离效应．

光纤随机色散对孤子系统通信容量的影响及抑制

研究了色散随机变化对光纤孤子通信容量的影响并给出减少该影响的方法。结果表明,随机色散的存在会使孤子到达时间产生抖动,该抖动与随机色散虚部的均方根成正比,且与孤子的振幅及速度有关;

色散随机变化对光纤中黑孤子传输特性的影响

本文研究了色散随机变化对单模光纤中黑孤子传输特性的影响。结果表明 :只有与频率有关的随机色散变化对黑孤子的频率和位置产生影响。

色散随机变化对暗孤子传输系统时间抖动的影响及抑制

运用守恒量扰动法，研究了色散随机变化对暗孤子传输系统的影响。结果表明：色散随机变化增大了暗孤子到达检测窗口的时间抖动方差而降低了暗孤子传输系统的容量。引入非线性增益可以有效地抑制色散随机变化对暗孤子到达时间抖动的影响。

Exact Solutions and Coherence Structures of Generalized Breor-Kaup Equations

Using the mapping method based on q-deformed hyperbolic functions,the exact solutions of generalizedBreor-Kaup equations are obtained.Based on the solutions,two coherent structures,periodic-branch kink and non-propagating kink,have been obtained.Moreover,one solitonal interaction form,two line solitons interaction on the kinkbackground,has been found.

Velocity and Dispersion for a Two-Dimensional Random Walk

In the paper,we consider the transport of a two-dimensional random walk.The velocity and the dispersionof this two-dimensional random walk are derived.It mainly show that:(i)by controlling the values of the transition rates,the direction of the random walk can be reversed;(ii)for some suitably selected transition rates,our two-dimensionalrandom walk can be efficient in comparison with the one-dimensional random walk.Our work is motivated in part by thechallenge to explain the unidirectional transport of motor proteins.When the motor proteins move at the turn pointsof their tracks(i.e.,the cytoskeleton filaments and the DNA molecular tubes),some of our results in this paper can beused to deal with the problem.

带有时间周期色散和时间变化损耗或增益的随机Schrodinger方程

本文考虑了一类在非线性光学中出现的带有时间周期色散和时间变化损耗或增益的随机非线性Schrodinger方程idu+1/εm(t/ε2)■xxudt+ν(t/ε)+■xxudt+λ|u|^2σudt+iεa(t)udt=0.我们首先修正了de Bouard和Debussche的文献[J.Funct.Anal.,2010,259(5):1300-1321]中建立的Strichartz型估计,然后利用它们证明了含有白噪声色散的随机Schrodinger方程的局部适定性.该随机方程是原方程的极限模型.最后,当参数ε→0时,在一维空间中证明了原方程解的局部渐近收敛性.

Pattern Structure of Deterministic Displacement in Random Porous Media with Dispersion Effect

A new model — model of random porous media degradation via several fluid displacing, freezing, and thawing cycles is introduced and investigated in this paper. The fluid transport is based on the deterministic method with dispersion effect. The result shows that the topology and the geometry of the porous media have a strong effect on displacement processes. The cluster size of viscous fingering (VF) pattern in percolation cluster increases with the increase of iteration parameter n. When iteration parameter , VF pattern does not change with n. We find that the displacement fluid forms trapping regions in random porous media with dispersion effect. And the trapping regions will expand with the increasing of the iteration parameter n. When r (throat size) and , the peak value of the distribution increases as n increases, where is the normalized distribution of throat sizes after different displacement-damages but before freezing. The peak value of the distribution reaches a maximum when and , where is the normalized distribution of the size of invaded throat. This result is different from invasion percolation. It is found that the sweep efficiency E increases along with the increasing of iteration parameter n and decreases with the network size L, and E has a minimum as L increases to the maximum size of lattice. The VF pattern in percolation cluster has one frozen zone and one active zone.

Theoretical simulation of chromatographic separation based on random diffusion in the restricted space

The diffusion behavior of particles in the chromatography is a fundamental issue of chromatographic dynamics. The understanding of the diffusion behaviors is particularly critical to optimize the operation conditions, improve the chromatographic performance and design a new separation device. Many of the present simulations focus on chromatographic thermodynamics, and very few aim at the overall diffusion and separation process. In order to dynamically trace the trajectory of the diffusing particles and to perform simulations of the whole chromatographic process, we have developed a model based on the framework of random walk in the restricted space and performed the simulation of a single particle diffusion in the gas chromatography. The simulation parameters were determined by comparing with the experimental data. The elution profiles of n-alkanes under different flow rates were accurately simulated with the method. The results show that the relative difference between the measures and the simulations are less than 2% and 10% for the retention time and the peak width, respectively. The simulation method shows great significance for the optimization of separation conditions and the development of novel technologies of chromatographic separation.