目标极点提取的改进算法

针对强电磁脉冲孔耦合瞬态响应的极点参数提取问题,将传统的矩阵束算法进行改进。通过对含有噪声的瞬态响应数据进行互相关处理,能有效提高低信噪比时极点的提取精度。再将数据经离散化后构造Hankle矩阵,结合奇异值分解,求解其广义特征值,即可提取信号的极点参数信息。最后通过仿真分析以及对波形的重构,验证改进算法具有抗噪能力强、拟合度高的特点。     

排队系统的渐近泊松话务过程

在文中,我们首先给出由马氏过程的一些跳跃时刻形成的简单点过程的有限维分布族弱收敛到泊松过程的相应分布族的条件,并讨论了有限维分布族弱收敛到泊松过程相应分布族的平稳马氏排队系统的话务过程,其次,我们证明了ＧＩ／Ｍ／１排队系统的离去过程的有限维分布族在重话务的情况下弱收敛到泊松过程的相应分布族。     

CONTRIBUTION FROM MOLDCULAR FIELD TO THE TEMPERATURE DEPENDENCE OF TUNNELING MAGNETORESISTANCE

Based on the nearly free-electron approximation, we have investigaed the temperature (T) dependence of spin-polarized tunneling in the magnetic tunnel junction with an asymmetrical barrier, with emphasis on the variation of molecular field with T in the same way as that of surface magnetization. It is found that the Slonczewski model can describe well the T depen-dence of spin-polarized tunneling, while the Julliere model only describes the T dependence of JMR qualitatively, but does accurately that of the difference of tunneling conductance between the parallel and antiparallal alignments for the magnetizations of FMs; Differing from the pre-vious finding, we find the electron spin polarization is not strictly proportional to the surface magnetization, for the former decreases with the increasing T more rapidly than the latter does.