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容差模拟电路故障模糊诊断方法及其实现 总被引:1,自引:3,他引:1
提出了基于SOFM神经网络的容差模拟电路故障模糊诊断方法及其实现。该方法将网络撕裂法和SOFM神经网络相结合进行故障测试.并运用所设计的模糊逻辑神经网络系统判断测试条件,定位容差模拟电路的子网络级故障。仿真试验表明该方法故障定位精确度高。撕裂迅速,有利于大规模容差模拟电路故障诊断的实现。 相似文献
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在用双向能量正交法对网络进行故障诊断时,网络的空差会影响结果的准确性。本文分析了由网络容差所造成的误差,给出容差所造成的能量误差的一个上界。在容差统计特性已知的情况下,对判别其偏差是否由故障引起的一个概率上的估计。 相似文献
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模拟电路故障诊断的新故障字典法 总被引:16,自引:0,他引:16
基于节点电压灵敏度,将文献[1]中的线性无容差电路的故障字典法推广到可以诊断容差模拟电路和非线性电路软故障的新故障字典法。讨论了该方法的原理和字典的建立方法,给出了仿真实例。 相似文献
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容差电路的K故障屏蔽方法研究 总被引:7,自引:0,他引:7
本文对线性电路的等输入/输出K故障屏蔽方法在容差情况下的应用进行了详尽的研究,所提两种K故障模糊屏蔽算法,计算量小,诊断速度快,故障与容差之间的模糊性低,可信度高。 相似文献
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本文根据存在容差时电路的特点,对现有的故障字典法作了改进。提出了一种能有效地解决有容差情况下最佳测试节点选取问题的新方法——混叠集分析法。对这种新方法进行了理论分析,提出了相应的算法,并在计算机上对实例进行仿真验证,证明该法是有效的。与基本的故障字典法相比,在很大程度上提高了诊断效率。 相似文献
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非线性容差电路的故障诊断 总被引:3,自引:0,他引:3
文章着重讨论如何根据容差电路有限可及点上的电压测量,诊断其线性和(或)非线性元件故障,文章利用Grassmann流形中的子空间距离证明了ε-故障锥的存在,并由此导出容差干扰下的可诊性条件。为了区别非线性元件的自身故障与似故障。本文仔细分析了可及点电压变化阵的方向能量椭球,并提出了相对方向能量准则。仿真表明,该准则对容差影响是鲁棒的。 相似文献
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隐层神经元冗余是提高神经网络容错性的一个有效的方法,在神经网络分类器的容错设计中,这一方法得到了良好的效果,对单故障可以做到完全容错.但是这一应用仅仅只能应用于输出层为硬限幅函数的前向网络,并且只证明了对网络中单故障有效.在实际应用中,网络中的各个节点和权值的故障往往是普遍存在的,因此本文提出了一种隐层冗余结构,对普遍故障存在下隐层神经元冗余容错方法做以评估,得出的结论是应用这种隐层神经元冗余结构可以减小网络的全局故障率;并提出了针对一般前向神经网络的实用的隐层神经元容错方法,这种方法可以有效地提高网络在普遍故障下的容错能力. 相似文献
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给出了用于模拟电路元件参数识别的多频传递函数法的过程,并对故障诊断方程的可解度进行了分析,在此基础上,将诊断方程的求解转化为非线性函数的优化问题,并运用改进的遗传算法来解决这个问题,算法实例表明该方法简化了故障诊断方程的求解过程,加速了容差电路故障元件的定位,有一定的应用价值。 相似文献
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Beside universality and very low latency, Youssef's randomized self-routing algorithms [25] have high tolerance for multiple
faults and more strikingly have the potential for fault tolerance without diagnosis. In this paper we study the performance
of Youssef's routing algorithms for faulty Clos networks in the presence of multiple faults in multiple columns with and without
fault detection. We show that with fault detection and diagnosis, randomized routing algorithms provide scalable, very efficient
and fault tolerant routing mechanisms. Without fault detection and diagnosis, randomized routing provides good fault tolerance
for faulty switches in either the first or the second column. The delays become large for faults in the third column or for
faults in more than one column. In conclusion, randomized routing enables the system to run without periodic fault detection/diagnosis,
and if and when the performance degrades beyond a certain threshold, diagnosis can be performed to improve the routing performance.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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静态随机存储器(Static Random Access Memory, SRAM)型现场可编程门阵列(Field Programmable Gate Array, FPGA)广泛应用于航空航天系统中,但是高空中FPGA易受高能粒子影响造成配置出错,互联资源上发生的单点错误可能导致跨域故障,使芯片内多个模块同时失效。跨域故障可能导致电路中的工作模块与检错模块同时故障,使设备中存在不能被检测到的隐蔽故障。针对上述问题,提出在芯片上将不同功能的模块相互隔离,并通过约束实现模块间可信通信的故障隔离方法,将故障限定在单一模块内,防止多个模块同时失效,提高电路的容错能力。通过故障注入评估隔离设计前后的航空电子全双工交换式以太网(Avionics Full Duplex Switched Ethernet, AFDX)电路的各类故障发生率。实验结果证明隔离设计可以与电路原有的检错容错机制结合,将隐蔽故障的发生率降为原来的3%。 相似文献
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Fault diagnosis and its prediction in wireless sensor networks using regressional learning to achieve fault tolerance 下载免费PDF全文
Rakesh Ranjan Swain Pabitra Mohan Khilar Tirtharaj Dash 《International Journal of Communication Systems》2018,31(14)
Due to the wide range of critical applications and resource constraints, sensor node gives unexpected responses, which leads to various kind of faults in sensor node and failure in wireless sensor networks. Many research studies focus only on fault diagnosis, and comparatively limited studies have been conducted on fault diagnosis along with fault tolerance in sensor networks. This paper reports a complete study on both 2 aspects and presents a fault tolerance approach using regressional learning with fault diagnosis in wireless sensor networks. The proposed method diagnose the different types of faulty nodes such as hard permanent, soft permanent, intermittent, and transient faults with better detection accuracy. The proposed method follows a fault tolerance phase where faulty sensor node values would be predicted by using the data sensed by the fault free neighbors. The experimental evaluation of the fault tolerance module shows promising results with R2 of more than 0.99. For the periodic fault such as intermittent fault, the proposed method also predict the possible occurrence time and its duration of the faulty node, so that fault tolerance can be achieved at that particular time period for better performance of the network. 相似文献
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Doumar A. Ito H. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2003,11(3):386-405
Topics related to the faults in SRAM-based field programmable gate arrays (FPGAs) have been intensively studied in recent research studies. These topics include FPGA fault detection, FPGA fault diagnosis, FPGA defect tolerance, and FPGA fault tolerance. This paper provides a guided tour to the approaches related to these topics. These include techniques, which are applied to the FPGA and others which have been recently introduced and can be applied to today's FPGAs. 相似文献
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Emmert J.M. Stroud C.E. Abramovici M. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2007,15(2):216-226
Most adaptive computing systems use reconfigurable hardware in the form of field programmable gate arrays (FPGAs). For these systems to be fielded in harsh environments where high reliability and availability are a must, the applications running on the FPGAs must tolerate hardware faults that may occur during the lifetime of the system. In this paper, we present new fault-tolerant techniques for FPGA logic blocks, developed as part of the roving self-test areas (STARs) approach to online testing, diagnosis, and reconfiguration . Our techniques can handle large numbers of faults (we show tolerance of over 100 logic faults via actual implementation on an FPGA consisting of a 20 times 20 array of logic blocks). A key novel feature is the reuse of defective logic blocks to increase the number of effective spares and extend the mission life. To increase fault tolerance, we not only use nonfaulty parts of defective or partially faulty logic blocks, but we also use faulty parts of defective logic blocks in nonfaulty modes. By using and reusing faulty resources, our multilevel approach extends the number of tolerable faults beyond the number of currently available spare logic resources. Unlike many column, row, or tile-based methods, our multilevel approach can tolerate not only faults that are evenly distributed over the logic area, but also clusters of faults in the same local area. Furthermore, system operation is not interrupted for fault diagnosis or for computing fault-bypassing configurations. Our fault tolerance techniques have been implemented using ORCA 2C series FPGAs which feature incremental dynamic runtime reconfiguration 相似文献
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Occurrence of faults in Network on Chip (NoC) is inevitable as the feature size is continuously decreasing and processing elements are increasing in numbers. Faults can be revocable if it is transient. Transient fault may occur inside router, or in the core or in communication wires. Examples of transient faults are overflow of buffers in router, clock skew, cross talk, etc.. Revocation of transient faults can be done by retransmission of faulty packets using oblivious or adaptive routing algorithms. Irrevocable faults causes non-functionality of segment and mainly occurs during fabrication process. NoC reliability increases with the efficient routing algorithms, which can handle the maximum faults without deadlock in network. As transient faults are temporary and can be easily revoked using retransmission of packet, permanent faults require efficient routing to route the packet by bypassing the nonfunctional segments. Thus, our focus is on the analysis of adaptive minimal path fault tolerant routing to handle the permanent faults. Comparative analysis between partial adaptive fault tolerance routing West-First, North-Last, Negative-First, Odd Even, and Minimal path Fault Tolerant routing (MinFT) algorithms with the nodes and links failure is performed using NoC Interconnect RoutinG and Application Modeling simulator (NIRGAM) for the 2D Mesh topology. Result suggests that MinFT ensures data transmission under worst conditions as compared to other adaptive routing algorithms. 相似文献
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《Circuits and Systems II: Express Briefs, IEEE Transactions on》2008,55(12):1279-1283