Sampled‐Data Approach to State Estimation Performance for Heterogeneous Distributed System with Fault

This paper considers the state estimation performance for heterogeneous distributed system with fault based on sampled‐data measurement. Firstly, a performance index for distributed state estimation is proposed. Based on the sampled‐data measurement of the heterogeneous distributed system, distributed state estimators are constructed. It is proved that by analyzing the distributed state estimation error systems, the required performance index for overall state estimation can be obtained using linear matrix inequality method. Finally, a simulation example is used to illustrate the effectiveness of the proposed theoretical scheme.     

Optimization of neural network model using modified bat-inspired algorithm

The success of an artificial neural network (ANN) strongly depends on the variety of the connection weights and the network structure. Among many methods used in the literature to accurately select the network weights or structure in isolate; a few researchers have attempted to select both the weights and structure of ANN automatically by using metaheuristic algorithms. This paper proposes modified bat algorithm with a new solution representation for both optimizing the weights and structure of ANNs. The algorithm, which is based on the echolocation behaviour of bats, combines the advantages of population-based and local search algorithms. In this work, ability of the basic bat algorithm and some modified versions which are based on the consideration of the personal best solution in the velocity adjustment, the mean of personal best and global best solutions through velocity adjustment and the employment of three chaotic maps are investigated. These modifications are aimed to improve the exploration and exploitation capability of bat algorithm. Different versions of the proposed bat algorithm are incorporated to handle the selection of the structure as well as weights and biases of the ANN during the training process. We then use the Taguchi method to tune the parameters of the algorithm that demonstrates the best ability compared to the other versions. Six classifications and two time series benchmark datasets are used to test the performance of the proposed approach in terms of classification and prediction accuracy. Statistical tests demonstrate that the proposed method generates some of the best results in comparison with the latest methods in the literature. Finally, our best method is applied to a real-world problem, namely to predict the future values of rainfall data and the results show satisfactory of the method.     

Fuzzy utility mining with upper-bound measure

Fuzzy utility mining has been an emerging research issue because of its simplicity and comprehensibility. Different from traditional fuzzy data mining, fuzzy utility mining considers not only quantities of items in transactions but also their profits for deriving high fuzzy utility itemsets. In this paper, we introduce a new fuzzy utility measure with the fuzzy minimum operator to evaluate the fuzzy utilities of itemsets. Besides, an effective fuzzy utility upper-bound model based on the proposed measure is designed to provide the downward-closure property in fuzzy sets, thus reducing the search space of finding high fuzzy utility itemsets. A two-phase fuzzy utility mining algorithm, named TPFU, is also proposed and described for solving the problem of fuzzy utility mining. At last, the experimental results on both synthetic and real datasets show that the proposed algorithm has good performance.     

煤炭自动化装车系统数据回传技术研究

针对部分煤炭自动化装车系统因通信不便而无法及时回传数据的问题,提出了基于3G模式的自动化装车系统数据回传技术:采用CDMA2000实现自动化装车系统对公网的无线接入,通过OPC服务器实现上位机与现场生产系统PLC之间的数据收发,采用数据收集软件Transaction Manager完成OPC服务器和数据库之间的衔接。     

颤振试飞测试系统的设计与实现

颤振是飞机结构最危险的振动形式;飞机颤振飞行试验属于防颤振研究的最终环节,它是验证新机颤振安全性必不可少的关键试飞课题;为完成颤振飞行试验,设计了一套高可靠性综合机载测试系统,完成模拟量、飞控数据、总线数据采集,并可实现实时数据处理;该测试系统硬件具有接口简洁、实时性强、抗干扰特性好,适用于航空试飞领域;根据试验数据分析暴露的问题,进行了深入研究,提出了合理解决方案,解决了颤振飞行试验过程中出现的问题,对于今后的颤振试飞测试具有指导意义。     

S1000D标准下数据模块发布样式的研究

为促进S1000D标准在以信息化为中心的综合保障技术中的应用,提高装备技术文档制作和发布的正确性和效率,文章研究了S1000D标准对PDF格式发布样式的规定,分析了XSL的工作原理和各类技术信息的Schema模式,利用XSL-FO技术编写了把数据模块发布成PDF格式的XML文档,通过XMLSPY实现了技术文档的发布;通过实例展示了实现规定的发布样式的关键技术以及从数据模块到PDF发布样式的显示效果,证明了所用方法的正确性与实用性,为实现S1000D标准下的技术信息发布提供了新的可行方法.     

基于PCIe总线接口的EtherCAT从站网卡设计

在基于EtherCAT总线的集散式数据采集系统中,针对测量仪器的高速实时采集需求,设计了一款基于PCIe接口的EtherCAT从站网卡;该网卡将不含网络接口的工控机直接接入EtherCAT网络,从而为浪高、流速、浮体六自由度等物理量的高速实时采集提供了一种简便灵活的实现途径;文中首先介绍了从站网卡的总体结构,接着从硬件和软件两部分详细给出了从站网卡的设计思路,最后通过实验验证了所提方案的有效性;试验结果表明,该从站网卡完全满足对数据传输的实时性、同步性、速度和准确性的要求。     

基于有色Petri网的工作流故障诊断方法

工作流系统的故障自动诊断和定位是云计算环境提供持续服务的基础;为了提高工作流系统的故障诊断准确性,文章提出了一种基于有色Petri网的故障诊断方法;首先,用开放世系模型对工作流进行建模;然后,提出了一种基于有色Petri网的故障模型;最后,将工作流的开放世系模型转化为有色Petri网故障模型,并提出了相应的多故障诊断方法;实验表明,文章提出的方法不仅故障定位的准确率和执行效率高于相关算法,还能有效的识别系统中的多个故障.     

基于Android的分布式数据采集系统设计

随着无线传感网络技术的大量涌现,各种分布式测控系统得到了广泛的应用和研究.针对目前各种测控方法的不同,设计一种基于Android的分布式测控系统.主要论述了基于ZigBee的无线传感器网络,蓝牙通信帧格式,Android分中心数据接收和存储,远程数据上报.通过验证,基于Android的分布式测控系统操作简单,适用性强,能实现对环境信息的实时采集与远程上报,适用于多种特殊环境应用.     

基于ASI的高速数据传输接口的设计

介绍了一种基于ASI编码的高速数据传输接口设计方案。该传输接口利用NS公司的CLC007和CLC014芯片进行发送驱动和接受均衡,利用CYPRESS公司的CY78923和CY78933芯片进行编码和解码,采用ALTERA的FPGA实现数据缓冲与转换的功能,并通过对数据的分组打包和解包校验的方法,保证数据的完整性及正确性。编码产生的数据利用50n阻抗匹配的同轴电缆进行传输,传输速率最高可达400Mbps,传输距离最远可达200m。