A theoretical model for mid-and low-latitude ionospheric electric fields in realistic geomagnetic fields

The geomagnetic fields, which play important roles in the ionospheric dynamo, can greatly affect the global distribution of ionospheric electric fields, currents and other ionospheric electrodynamics phenomena. In the study of ionospheric electrodynamics phenomena, such as the longitudinal variations of ionospheric electric fields, the non-dipolar component of the geomagnetic fields must be taken into account. In this paper, we deduce a theoretical electric field model for ionospheric dynamo at mid- and low-latitude which adopt a modified magnetic apex coordinates system. In the new electric field model, the geomagnetic fields can be calculated from either the IGRF model or the dipole field model, and the neutral winds and conductivities are calculated based on empirical models. Then the dynamo equation for the electric potential is finally solved in terms of the line-by-line iteration method, and the ionospheric electric fields and currents are derived from the calculated potential. Our model can reproduce the main features of the ionospheric electrodynamics processes, so it will be a useful tool for the investigation of the upper atmosphere and ionosphere.     

分数次积分算子的双权不等式

首先推广了Ｅ．Ｔ．Ｓａｗｙｅｒ关于分数次积分算子的双权不等式的几个充分条件，所得结果更加接近于必要条件Ａ然后给出了与分数次极大算子相联系的另一充分条件．     

中日刑事强制措施制度之比较

刑事强制措施是刑事程序法的重要组成部分。但自1996年修改《刑事诉讼法》至今，由于立法观念及技术等方面的原因，刑事强制措施在立法和司法实践中暴露出许多问题。故从比较法的角度，对日本的刑事强制措施制度和我国的法制现状进行分析比较。并从我国司法实践出发，对刑事强制措施的改进提出若干建议。     

一个安全的主动网络编程语言模型

为解决主动网络安全威胁问题，从编程语言角度分析了语言级的主动网络的安全需求，使用软件机制而不是硬件机制保护主机防止恶意代码攻击，并折中了通信需求和程序语言需求，为主动网络提供了一个安全的编程语言模型。     

汽车事故记录仪

本文提出了汽车事故记录仪的设计思想及给出了其实现电路硬件设计方案，详细阐述了汽车事故记录仪中测量刹车速度的非接触测量方法－多普勒效应测速法。并以实验装置为依据，给出了实验数据，证明了该测速法用于汽车事故记录可行性和高精度的结果。     

An Improved S-Random Interleaver Design for Turbo Code Based on Chaos Model

A new method to design interleaver based on Henon chaos model is presented. The designed interleaver is with rather random behavior. Experimental results show that the proposed S-henon interleaver make a magnitude of im provement in bit error rate （BER） performance by 0.4 dB compared with the S-random interleaver for AWGN channel respectively. The S-henon interleaver may be adapted to 3G mobile communication systems.     

数据包络模型的随机性研究

利用最小绝对误差估计和机会约束规划，本文研究了数据包络模型中的随机性问题，建立了一系列线性与非线性规划的数据包络模型。并对模型解的存在和鲁棒性作了讨论。     

邓小平对中美关系的论述及其现实意义

1977年邓小平复出后十分重视中美关系，在他亲自领导下，中美关系有了很大的发展，其问，也经历了许多波折。邓小平对中美关系的重要性有正确的判断，对存在的问题有清醒的认识，对中美关系的斗争性有充分的准备。回顾邓小平对中美关系的论述，在当前中美关系依然错综复杂的情况下，有助于我们正确把握中美关系的航向，有助于中美关系健康稳定发展。