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71.
提出了一种新的基于紧致型小波神经网络的模拟电路故障诊断方法。该法首先利用小波包变换对故障信号进行预处理,减少了紧致型小波神经网络的输入数目,简化了紧致型小波神经网络结构,然后对紧致型小波神经网络进行训练和测试。仿真试验表明,该方法比普通BP神经网络方法训练速度更快,诊断准确率更高,容错能力强,非常适用于模拟电路故障诊断。 相似文献
72.
结合电喷发动机的维修特点,用Visual Prolog在可视化编程环境下进行了故障检测和维修系统的界面设计和程序源代码的编写。系统模拟现实的维修过程,为故障车建立维修档案,按照故障码提示进行检修。用一阶谓词表示诊断知识,使用文本文件形式存储知识,对发动机的常见故障,按故障发生率排序,指导维修。对于疑难故障,添加检修步骤,扩充知识库。 相似文献
73.
Fault diagnosis of full-scan designs has been progressed significantly. However, most existing techniques are aimed at a logic
block with a single fault. Strategies on top of these block-level techniques are needed in order to successfully diagnose
a large chip with multiple faults. In this paper, we present such a strategy. Our strategy is effective in identifying more
than one fault accurately. It proceeds in two phases. In the first phase we concentrate on the identification of the so-called
structurally independent faults based on a concept referred to as word-level prime candidate, while in the second phase we further trace the locations of the more elusive structural dependent faults. Experimental results
show that this strategy is able to find 3 to 4 faults within 10 signal inspections for three real-life designs randomly injected
with 5 node-type or stuck-at faults.
Part of this work has ever appeared in the proceedings of Asian Test Symposium in 2003.
Yu-Chiun Lin received his BS degrees in Electrical Engineering from National Central University in 2000, and MS degree from Electrical
Engineering of National Tsing Hua University in 2002. Since then, he has been with Ali Corporation as a design engineer. His
current interests include the design of USB controllers and imaging periperals.
Shi-Yu Huang received his BS, MS degrees in Electrical Engineering from National Taiwan University in 1988, 1992 and Ph.D. degree in Electrical
and Computer Engineering from the University of California, Santa Barbara in 1997, respectively. From 1997 to 1998 he was
a software engineer at National Semiconductor Corp., Santa Clara, investigating the System-On-Chip design methodology. From
1998 to 1999, he was with Worldwide Semiconductor Manufacturing Corp., designing the high-speed Built-In Self-Test circuits
for memories. He joined the faculty of National Tsing-Hua University, Taiwan, in 1999, where he is currently an Associate
Professor. Dr. Huang’s research interests include CMOS image sensor design, low-power memory design, power estimation, and
fault diagnosis methodologies. 相似文献
74.
75.
To achieve the evaluation of the lesion detectability of a program implemented by us on a minicomputer system to indicate possible defects on liver scans, we simulated a set of geometrical phantoms with different patterns of cold lesions to obtain LROC curves in different cases. Then, to check its clinical value, the program was applied to 44 liver scintigrams of patients among which 7 occurred to be pathological. These liver scintigrams had been evaluated by 6 clinicians so that a comparison between the program and the clinicians could be performedd on the basis of the corresponding LROC curves. Moreover, once an abnormality had been detected by the program, the abnormality was processed in order to perform a psychovisual evaluation of the image more easily: an adapted local 2-level display of the possible defect was superimposed on the scan to enhance it and to facilitate diagnosis. 相似文献
76.
加热炉炉管的红外热像监测方法研究 总被引:1,自引:1,他引:0
文中所介绍的乃是获奖项目“高温炉管的红外在线监测诊断及评估系统研究”科研成
果的一部分。试验研究结果表明,在进口的如PM350 类焦平面红外热像仪的基础上,合理地选装高温火焰滤片、广角镜头以及红外隔热罩,便可实现通过看火孔对加热炉炉管进行红外热像的在线监测。而通过试验研究所得到的误差修正方法,可以使炉管的红外热像监测结果与接触式的热电偶测试结果相差小于2 %。现场工业试验的结果表明,该方法完全满足了生产装置监测的需要。 相似文献
77.
78.
提出一种并行的决策树学习方法。该方法首先将数据库分为若干个子部分,针对每个子部分分别进行决策树学习,优选分裂属性,再对各个决策树学习的结果综合,生成最终的树。在树上剪枝以降低分类错误率。通过在变压器绝缘故障诊断中的应用表明该方法有很强的学习能力和诊断速度,是一种有效的决策树学习方法。 相似文献
79.
以领域专家的理论知识和经验知识为基础,采用了模糊推理,建立了心电诊断模糊专家系统的模型,克服了知识工程师对规则难以总结提取的困难,讨论了趋于增长的合成推理规则(CRI)方法,最后给出了实验结果。 相似文献
80.
针对出租车计价器辐射骚扰超标的问题,分析产生机理和原因,进行有效抑制.通过并接高频陶瓷电容器和在导线上套用磁珠两种方法改进后,辐射骚扰达到相关标准的要求. 相似文献