Optimal Design of Dual-Pump Fibre-Optical Parametric Amplifiers with Dispersion Fluctuations Based on Hybrid Genetic Algorithm

Solutions of dual-pump fibre-optical parametric amplifiers (DP-FOPAs) with dispersion fluctuations are derived by using a matrix operator. Based on these solutions and a hybrid genetic algorithm, we have optimized threesection DP-FOPAs to increase the signal band and improve the gain uniformity. The optimizations demonstrate that when dispersion fluctuations are taken into account, the 44-nm signal band with the 0.37-dB ripple and over 14.8-dB gain can be obtained from the three-section DP-FOPA, instead of the lowest gain of -13dB with the ripple of more than 15dB from the single-section DP-FOPA.     

Separability of Pure and Mixed States of the Quantum Network of Four Nodes

This article discusses the separability of the pure and mixed states of the quantum network of four nodes by means of the criterion of entanglement in terms of the covariance correlation tensor in quantum network theory.     

基于Fourier分析的中国股市波动周期研究

通过对沪深两市波动周期的实证分析 ,揭示了中国股市的周期性波动特征 ,并对两市波动的周期性进行了对比 ,为进一步研究我国资本市场的波动提供了依据 .     

中国股票市场波动非对称性特征研究

利用三种 GARCH-M模型实证分析了中国股票市场不同发展阶段波动的非对称性特征 .结果发现 ,中国股票市场存在显著的波动非对称性 ,并且在不同阶段呈现不同特点 .对三种模型进行比较的结果显示 ,EGARCH-M模型是描述中国股市波动非对称性特征的最优模型 .     

SHARP CRITERIONS OF GLOBAL EXISTENCE AND COLLAPSE FOR COUPLED NONLINEAR SCHRODINGER EQUATIONS

In this paper, a series of sharp criterions of global existence and collapse for coupled nonlinear Schr6dinger equations are derived out in terms of the characteristics of the ground state and the local theories. And the conclusion that how small the initial data are, the global solutions exist is proved.     

CAUCHY PROBLEM FOR QUASILINEAR HYPERBOLIC SYSTEMS WITH CHARACTERISTICS WITH CONSTANT MULTIPLICITY

For quasilinear hyperbolic systems with characteristics of constant multiplicity, suppose that characteristics of constant multiplicity(> 1) are linearly degenerate, by means of generalized normalized coordinates we get the global existence and the blow-up phenomenon of the C^1 solution to the Cauchy problem under an additional hypothesis.     

BV SOLUTIONS OF DIRICHLET PROBLEM FOR A CLASS OF DOUBLY NONLINEAR DEGENERATE PARABOLIC EQUATIONS

The uniqueness and existence of BV solutions to Dirichlet problem of doubly degenerate parabolic equations of the following form au/at=div(A(|↓△B(u)|↓△B(u))in QT=Ω×(0,T) are studied     

基于模糊关系的DEM数据信息伪装技术研究

提出一种DEM数据的信息伪装技术。应用Rabin方法生成单向Hash函数，结合波动方程随机生成DEM数据。构造模糊矩阵，生成为伪装DEM数据。非法用户无法获取真实地形数据，但是合法用户使用密码K就可以将真实的地形数据还原。该算法在隐蔽通讯领域有广阔应用前景。算法可以完全公开。     

沪深股市杠杆效应的实证分析

运用 E-GARCH模型对沪深股市的杠杆效应进行了实证分析 ,结果表明 ,日收益存在着明显的杠杆效应 ,收益对波动强度的影响具有非对称性 .