船舶操纵控制嵌入式训练系统设计与实现

嵌入式仿真训练系统将模拟训练与实装训练相结合,利用仿真技术,将模拟训练功能嵌入到真实武器平台中,利用真实武器系统进行高逼真度的训练,是改善训练模式,提高训练效能的有效途径。介绍嵌入式训练系统的原理及当前发展现状;对船舶操纵控制系统模块进行分析,提出了系统改造的总体方案,并就嵌入式训练系统与实际操作之间的安全切换、嵌入式训练系统建模技术、仿真评估及故障仿真等关键技术进行研究。通过嵌入式训练功能加装,可以提高装备训练能力,降低训练成本,并为新研制装备的嵌入式模拟训练系统提供理论支持,具有非常重要的意义。     

基于神经网络的多电平逆变电路故障诊断

因含有大量的开关器件,多电平逆变器难以用基于模型的方法进行故障诊断。针对这一问题,提出了一种基于神经网络的故障识别和分类方法。采用载波相移脉冲宽度调制（PWM）策略搭建级联五电平逆变电路,对逆变器的输出电压信号进行快速傅里叶变换,获取其频谱并以此作为特征信息。利用反向传播算法（BP）神经网络对输出电压模式进行分类。Matlab仿真结果表明,本文设计的 BP神经网络有效地实现了对逆变器的故障诊断。     

ARINC429总线的故障注入测试方法

传统的ARINC429总线测试仅针对输入的激励测试输出的响应, 无法有效涵盖更多在异常状态下的测试环境。为扩大测试的覆盖性与主动性, 采用故障注入的方法, 分别对ARINC429总线物理层、电气层和协议层中典型的故障模式及注入实现方法进行了研究, 实验结果验证了故障注入测试方法的有效性。     

Fault Diagnosis Based on the Updating Strategy of Interval-Valued Belief Structures

This paper presents the dynamic method for fault diagnosis based on the updating of Interval-valued belief structures （IBSs）. The classical Jeffrey＇s updating rule and the linear updating rule are extended to the framework of IBSs. Both of them are recursively used to generate global diagnosis evidence with the form of Interval basic belief assignment （IBBA） by updating the previous evidence with the incoming evidence. The diagnosis decision can be made by global diagnosis evidence. In the process of evidence updating, the similarity factors of evidence are used to determine switching between the extended Jef frey＇s and linear updating rules, and to calculate the linear combination weights. The diagnosis examples of machine rotor show that the proposed method can provide more reliable and accurate results than the diagnosis methods based on Dempster-Shafer evidence theory.     

Framework for distributed autonomic self‐healing in fixed IPv6 networks

A main requirement for the Future Internet is to enable self‐management behaviors facilitating the network to adapt to changing conditions and self‐heal in the face of erroneous states. On the basis of Autonomic Fault‐Management principles, this paper proposes a framework consisting of a set of components operating inside the network elements and allowing the devices to collaboratively realize self‐healing. In that context, Autonomic Fault‐Management is intuitively constituted by the detection of the presence of faulty conditions, followed in turn by the self‐diagnosis and identification of the corresponding root causes, and completed consequently by the removal of the identified root causes and their effects. The proposed framework implements a distributed control loop that interacts with the network operations personnel in case the current erroneous state is not resolvable by means of Autonomic Fault‐Management. We argue that there are a number of mutual benefits between our proposed framework and the IPv6 protocol suite. This is demonstrated by a case study that illustrates these benefits and shows how the capabilities of IPv6 can be enhanced through the self‐healing mechanisms of the proposed framework. Finally, the prototype implementation used for the case study is analyzed in terms of scalability and overhead produced in the network nodes. Copyright © 2013 John Wiley & Sons, Ltd.     

Improved Shamir's CRT‐RSA Algorithm: Revisit with the Modulus Chaining Method

RSA signature algorithms using the Chinese remainder theorem (CRT‐RSA) are approximately four‐times faster than straightforward implementations of an RSA cryptosystem. However, the CRT‐RSA is known to be vulnerable to fault attacks; even one execution of the algorithm is sufficient to reveal the secret keys. Over the past few years, several countermeasures against CRT‐RSA fault attacks have tended to involve additional exponentiations or inversions, and in most cases, they are also vulnerable to new variants of fault attacks. In this paper, we review how Shamir's countermeasure can be broken by fault attacks and improve the countermeasure to prevent future fault attacks, with the added benefit of low additional costs. In our experiment, we use the side‐channel analysis resistance framework system, a fault injection testing and verification system, which enables us to inject a fault into the right position, even to within 1 μs. We also explain how to find the exact timing of the target operation using an Atmega128 software board.     

基于物联网技术的光伏照明故障监测系统设计

分析了传统光伏照明系统存在的问题,结合物联网技术的特点和优势,提出了一种基于物联网技术的光伏照明故障监测系统的设计方案。系统以cc2530作为各个ZigBee无线网络节点的微控制器．采用具有综合信息处理功能的STM32为主控制器,构建了本故障监测系统的硬件平台。通过ZigBee协议栈实现光伏系统无线传感网络的软件架构,从而达到远程监测系统故障的目的。测试表明：系统运行稳定,操作灵活,具有节电性能和良好的通讯功能。     

七号信令在移动通信故障定位中的应用

7号信令是由ITU-T制定的全球电信业的标准。这个标准指定了在通信中各个网络点通过数字信令网交换信息的过程及协议。在以电路交换为基础的GSM网络中,信令流程是一切通信过程的基本。只有确实掌握MS呼叫、位置更新、切换等通信过程中各接口的信令流程,才能有针对性地对网络故障进行分析定位。文中重点分析了GSM网络中位置更新的信令流程,结合信令监测系统获取的有效信令信息,对故障实例进行了分析,建立了一般的故障处理流程。     

500kV变电站光纤通信常见故障分析及防范措施研究

文中论述了变电站光纤通信的基本原理,对湖北500 kV变电站光纤通信常见故障进行了分析,制定了相关防范措施。对变电站光纤通信施工及日常维护工作有一定参考价值。     

基于六氟化硫气体分解物的高压设备专家诊断系统

本文采用小波神经网络的专家诊断方法,提出了一种基于六氟化硫气体分解物的高压设备专家诊断系统的思路和方法,并且将良好的软件和硬件协同应用于高压设备专家诊断中,用于分析气体分解物的含量并做出高压设备的故障判断与对故障的预测。介绍专家诊断系统的硬件组成和软件实现方式,并通过与其他业内常用方法的比较进而突出本方法的优势。最后,通过分析一些列实验数据证明专家诊断系统的可靠性和实用性。