一种DDOS在线检测法

由DDoS攻击时流量样本与Hurst指数的关系,得到检测DDoS的方法.以提升小波估计Hurst指数法为基础,设计出小波算法的能谱在线计算方法.与传统检测法相比,本法可在线观察业务流特征,能及时发现DDOS入侵。     

“数字海洋”原型系统设计与实现初步

基于现有数字海洋的概念及其相关研究,结合对我国数字海洋建设战略部署的分析,设计了中国数字海洋原型系统框架;另外,根据用户类型和应用需求的不同,设计了数字海洋原型系统公众版和管理版的功能模块;并从数据处理流程和信息服务需求角度分析了数字海洋原型系统数据处理及信息服务模式;最后给出了原型系统实现的初步进展。     

基于无线红外通讯的新型球场换人牌设计

本文设计了一种新型的基于无线红外通讯的电子式换人牌,通过无线红外通讯模块与单片机接口的应用,使得换人牌的显示信息由手操器无线传达。本文分析了红外通信原理,利用串行通信接口进行红外收发。设计硬件电路及相配合的软件程序,设计了震荡发生器,应用X5045进行数据存储和看门狗,应用74HC595进行数据的串入并出等。经试验证明可能够提高执场裁判员的工作效率,降低显示信息出错的几率。     

基于Fisher判别法的脑电图数据分析的研究

目的本文通过对客观记录的受试者脑电图数据进行Fisher判别分析,判断其能否应用于脑电数据特征提取和分类决策。为脑电图研究的其它分析做基础分析。方法根据α波的强弱不同将21导电极分为四类,分别对63例正常状态下受试者21导联电极的脑电图数据进行Fisher判别分析,并利用误判率回代估计法检验判别准确率。数据处理和统计分析采用独立设计的脑电图分析工具箱和Fisher判别分析程序。结果表明对63例正常状态下受试者的脑电图数据进行Fisher判别分析,预测各电极分类准确率82.3%。结论Fisher判别法预测准确率较高,脑电特征(主要为α波)提取较为准确,能较好的应用于脑电数据特征提取和分类决策中,从而辅助脑电图的检查和定量分析,为脑电图的检验提供有效的分析手段。     

SIISAM: A Model for Secure Inhomogeneous Information Systems

SIISAM is a multilayered, Web-service-based architecture model designed to guide construction of a secure, interoperable, and extensible information system that allows smooth interoperation of legacy applications. A pilot e-government system in China built using the model has achieved its targets in both functionality and performance.     

Results on rotation symmetric polynomials over GF(p)

In this paper, we generalize the recent counting results about rotation symmetric Boolean functions to the rotation symmetric polynomials over finite fields GF(p). By using Möbius function, we obtain some formulas for more general n, the number of variables. Some known formula in Boolean case are simplified.     

An application of MODIS data to snow cover monitoring in a pastoral area: A case study in Northern Xinjiang, China

Snow is an important land cover on the earth's surface. It is characterized by its changing nature. Monitoring snow cover extent plays a significant role in dynamic studies and prevention of snow-caused disasters in pastoral areas. Using NASA EOS Terra/MODIS snow cover products and in situ observation data during the four snow seasons from November 1 to March 31 of year 2001 to 2005 in northern Xinjiang area, the accuracy of MODIS snow cover mapping algorithm under varied snow depth and land cover types was analyzed. The overall accuracy of MODIS daily snow cover mapping algorithm in clear sky condition is high at 98.5%; snow agreement reaches 98.2%, and ranges from 77.8% to 100% over the 4-year period for individual sites. Snow depth (SD) is one of the major factors affecting the accuracy of MODIS snow cover maps. MODIS does not identify any snow for SD less than 0.5 cm. The overall accuracy increases with snow depth if SD is equal to or greater than 3 cm, and decreases for SD below 3 cm. Land cover has an important influence in the accuracy of MODIS snow cover maps. The use of MOD10A1 snow cover products is severely affected by cloud cover. The 8-day composite products of MOD10A2 can effectively minimize the effect of cloud cover in most cases. Cloud cover in excess of 10% occurs on 99% of the MOD10A1 products and 14.7% of the MOD10A2 products analyzed during the four snow seasons. User-defined multiple day composite images based on MOD10A1, with flexibilities of selecting composite period, starting and ending date and composite sequence of MOD10A1 products, have an advantage in effectively monitoring snow cover extent for regional snow-caused disasters in pastoral areas.     

一种高性价比CAN总线适配卡的设计与实现

针对传统CAN总线设备存在的系统规模大、功耗高、成本高等问题,提出并实现了一种高性价比CAN适配卡系统。介绍了系统总体结构,阐述了软硬件组成及其功能,并给出硬件具体设计方案及驱动程序的实现方法。经实践证明,该适配卡系统完全可满足实际需要且结构简单、能耗低、稳定性能好。     

Small sample improvements in the threshold cointegration test using residual-based moving block bootstrap

A residual-based moving block bootstrap procedure for testing the null hypothesis of linear cointegration versus cointegration with threshold effects is proposed. When the regressors and errors of the models are serially and contemporaneously correlated, our test compares favourably with the Sup LM test proposed by Gonzalo and Pitarakis. Indeed, shortcomings of the former motivated the development of our test. The small sample performance of the bootstrap test is investigated by Monte Carlo simulations, and the results show that the test performs better than the Sup LM test.     

Techniques for pipelined broadcast on ethernet switched clusters

By splitting a large broadcast message into segments and broadcasting the segments in a pipelined fashion, pipelined broadcast can achieve high performance in many systems. In this paper, we investigate techniques for efficient pipelined broadcast on clusters connected by multiple Ethernet switches. Specifically, we develop algorithms for computing various contention-free broadcast trees that are suitable for pipelined broadcast on Ethernet switched clusters, extend the parametrized LogP model for predicting appropriate segment sizes for pipelined broadcast, show that the segment sizes computed based on the model yield high performance, and evaluate various pipelined broadcast schemes through experimentation on Ethernet switched clusters with various topologies. The results demonstrate that our techniques are practical and efficient for contemporary fast Ethernet and Giga-bit Ethernet clusters.