基于加权因子的光电经纬仪航迹测量

针对光电经纬仪测量的异面定位误差,采用加权因子算法进行调整;首先建立空中测量目标的定位模型,为避免因各种误差对测量数据的影响,接着用加权因子对目标无偏估计,通过调整加权因子提高测量模型的精度,最后建立模型并进行仿真实验,得到了精确的航迹坐标,仿真结果表明减少虚假航迹,提高对被测目标的定位精度。     

基于MAXQ3108+DS8102的三相智能电能表设计

针对目前市场上采用电磁式电流互感器作为电流传感器的三相智能电能表计量精度普遍易受外部强磁场干扰的不足,采用美信半导体公司提出的MAXQ3108+DS8102芯片组,解决方案设计了一款采用锰铜分流器作为电流传感器的三相智能电能表,解决了锰铜分流器采样电流方式下各相电压、电流信号与数据采集MCU电气隔离的技术瓶颈,并详细阐述了信号采集与测量的过程;样机测试结果表明:文中设计的三相智能电表能够有效抑制外部强磁场干扰,有功电能计量精度满足IEC62053标准中有功0.5S级相关技术指标要求。     

一种减少测距误差的传感器网络定位算法

接收信号强度(RSSI)常被作为无线传感器网络定位算法的测距技术,通常,获取的RSSI信号序列中同时存在随机误差和粗差两种误差,利用以往常用的算法都难以消除混合误差对RSSI测量统计数据的影响;在分析两种误差特征的基础上,提出了一种基于统计中值的加权定位算法,算法在去除粗差的基础上,能在一定程度上平滑了随机误差,算法不仅提高了定位的精度,同时提高了节点的覆盖率;理论分析和仿真结果都表明算法具有较高的定位精度和覆盖率,最优情况下定位精度较原先算法能够提高6.99%,而不可定位节点比例下降8.05%。     

参数稀疏信号非均匀采样性能分析

提出了一种参数稀疏信号的时间交替周期非均匀采样方案。相对于非均匀采样,周期非均匀采样可以在降低系统复杂度的前提下依然保持较高的转换速率。通过仿真证明,非均匀采样样本的超分辨率特性可以提高非线性最小二乘周期图谱估计的重构性能。     

参数未知的自适应耦合同步及其在保密通信中的应用

在实际应用中,系统参数会随着环境的变化而变化,因此研究参数不确定混沌系统的同步更具有实际应用价值。文章针对参数完全未知的混沌系统,基于单向耦合同步方法,实现了混沌系统的自适应同步,为证明系统同步进行了严格的数学推导,并将同步的混沌系统应用到混沌保密通信中。计算机仿真表明混沌系统能够快速达到同步,且在混沌保密通信系统的接收端,有用信号可以有效地恢复出来,从而证明文章提出的方法有效且可行。     

ETL多数据流并行抽取中监控的研究与设计

对ETL多数据流并行抽取进行内容与流程的监控,并对各监控模块作了详细分析与设计,监控提高了数据抽取的效率与数据质量,有效保证了系统稳定运行与数据抽取的顺利进行。     

Parameter estimation and stabilization for a wave equation with boundary output harmonic disturbance and non‐collocated control

This paper is concerned with the parameter estimation and stabilization of a one‐dimensional wave equation with harmonic disturbance suffered by boundary observation at one end and the non‐collocated control at the other end. An adaptive observer is designed in terms of measured velocity corrupted by harmonic disturbance with unknown magnitude. The backstepping method for infinite‐dimensional system is adopted in the design of the feedback law. It is shown that the resulting closed‐loop system is asymptotically stable. Meanwhile, the estimated parameter is shown to be convergent to the unknown parameter as time goes to infinity. Copyright © 2010 John Wiley & Sons, Ltd.     

Research on the group decision-making about emergency event based on network technology

In order to improve decision-making efficiency about emergency event, this paper proposes a novel concept, i.e., Agile-Delphi Method, which is an integration of agile decision and Delphi Method implicating that the decision-makers instantly deliver, respond, treat, and utilize information via Delphi process while conducting group decision-making about emergency event. The paper details the mechanism of group decision-making about emergency event based on network technology and Agile-Delphi Method. Finally, the paper conducts an empiric analysis taking the “111 event”, i.e., the liquid ammonia spill event happened on November 1, 2006 in a phosphorus chemical company in China, as an example.     

Fire detection algorithms for video images of large space structures

In large space structures, the latest fire detection methods are based on video image processing and data fusion. But the false positive rate and false negative rate remain unsatisfactory and need improving. The emphases of this paper are target extraction and recognition. A new adaptively updating target extraction algorithm (NAUTEA) is proposed by which the intact target can be extracted in time. In addition, some fire video image recognition algorithms, such as fuzzy neural network (FNN) and FGALSSVM (Fuzzy GALSSVM), are studied and improved. To verify the performance of these algorithms, a prototype system is developed, and a series of algorithm tests on a fire video are conducted. These tests make it clear that, the accurate, robust and real-time fire detection can be realized.     

Rule acquisition and attribute reduction in real decision formal contexts

Formal Concept Analysis of real set formal contexts is a generalization of classical formal contexts. By dividing the attributes into condition attributes and decision attributes, the notion of real decision formal contexts is introduced. Based on an implication mapping, problems of rule acquisition and attribute reduction of real decision formal contexts are examined. The extraction of “if–then” rules from the real decision formal contexts, and the approach to attribute reduction of the real decision formal contexts are discussed. By the proposed approach, attributes which are non-essential to the maximal s rules or l rules (to be defined later in the text) can be removed. Furthermore, discernibility matrices and discernibility functions for computing the attribute reducts of the real decision formal contexts are constructed to determine all attribute reducts of the real set formal contexts without affecting the results of the acquired maximal s rules or l rules.