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A novel fault diagnosis method of bearing based on improved fuzzy ARTMAP and modified distance discriminant technique 总被引:1,自引:0,他引:1
Zengbing Xu Jianping Xuan Tielin Shi Bo Wu Youmin Hu 《Expert systems with applications》2009,36(9):11801-11807
This paper presents a novel intelligent diagnosis method based on multiple domain features, modified distance discrimination technique and improved fuzzy ARTMAP (IFAM). The method consists of three steps. To begin with, time-domain, frequency-domain and wavelet grey moments are extracted from the raw vibration signals to demonstrate the fault-related information. Then through the modified distance discrimination technique some salient features are selected from the original feature set. Finally, the optimal feature set is input into the IFAM incorporated with similarity based on the Yu’s norm in the classification phase to identify the different fault categories. The proposed method is applied to the fault diagnosis of rolling element bearing, and the test results show that the IFAM identify the fault categories of rolling element bearing more accurately and has a better diagnosis performance compared to the FAM. Furthermore, by the application of the bootstrap method to the diagnosis results it can testify that the IFAM has more capacity of reliability and robustness. 相似文献
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直线拟合快速实现的一种新算法 总被引:2,自引:1,他引:2
对三种基于残差准则的直线拟合方法进行分析并提出了一种直线拟合快速实现的新算法——参数逼近法;算法以变步长对斜率和截距进行逼近,降低了利用计算机进行直线拟合的复杂度;算法不仅容易实现,收敛速度快,而且可以根据需要自由控制拟合精度;另外,算法对3种准则的拟合均适用,从而将3种直线拟合法统一于一个体系之下。 相似文献
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为探究混流式喷水推进泵在运行过程中叶轮结构稳定性,基于单向流固耦合的方法,分别对叶轮结构在变流量、变转速工况下进行静力学分析和模态分析。结果表明:喷水推进泵叶轮背面及工作面的最大等效应力均发生在叶片根部;叶轮背面及工作面的最大位移均发生在靠近叶轮出口叶缘位置;流量变化对于叶轮结构固有频率的影响可近似忽略,其下降值为0.02~0.07 Hz;相较于流量对叶轮结构的影响,转速的变化对叶轮结构的影响较大,其增值为0.14~1.91 Hz;叶轮转速不应超过4 000 r/min,否则极容易诱发叶轮共振。 相似文献
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用于高速量子密码系统的1.25 GHz InGaAs/InP单光子探测器的研制 总被引:3,自引:1,他引:2
随着量子密码领域的快速发展,近红外单光子探测器的研究已经成为该领域的研究重点和技术制高点。报道了一种基于正弦门控与滤波技术的InGaAs/InP雪崩光电二极管(APD)高速单光子探测器,门控频率达到1.25GHz。在探测效率为10.3%时,暗计数概率为1.3×10-6/gate,后脉冲概率为5.6×10-5/ns。这种高速单光子探测器将大幅度提升量子密码系统的两个关键指标——密钥率和传输距离,为下一代高速量子密码系统的实用化应用奠定了基础。 相似文献
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