Results 51 to 60 of about 2,180 (133)
核熵成分分析(kernel entropy component analysis,KECA)方法在处理非线性数据集,去除冗余信息方面具有独特的优势。针对电力变压器故障诊断中有效特征提取困难,KECA中核参数选择繁琐以及忽略了样本类别信息等问题,文中提出一种自适应核函数优化学习的监督核熵成分分析特征提取方法,用于电力变压器敏感特征量的提取。首先收集电力变压器不同状态下的样本数据,并结合样本类别信息建立一个依赖数据的核函数 ...
彭丽维, 张彼德, 孔令瑜, 梅婷
doaj
Design and implementation of online learning assisted intelligent receiver [PDF]
To address the issue of reliable communication under complicated scenarios, an online learning-assisted intelligent OFDM receiver was proposed.The variations of the channel environment could be precepted by the receiver, and the optimal parameters of the
Haitao ZHAO +5 more
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急性卒中院前诊断识别研究进展(Research Progress in Prehospital Diagnosis and Identification of Acute Stroke)
卒中作为全球第二大死亡原因和首要致残因素,其救治效果高度依赖早期识别与及时治疗干预。目前,院前卒中预测工具主要包括传统量表、机器学习模型及生物标志物三大类,这些诊断工具各具特点但均存在明显局限性。传统量表(如FAST、辛辛那提院前卒中量表)因其操作简便成为基层筛查的主要手段,但对后循环卒中识别不足,而针对大血管闭塞的专项量表(如洛杉矶运动量表、动脉闭塞快速评价量表)虽特异性较高,但仍面临假阳性率偏高的问题。机器学习模型(如极端梯度提升、随机森林)在卒中分型及大血管闭塞预测中展现出优越性能 ...
王荣,何松,岗瑞娟,王琪,唐宇杰,刘飞凤,杨杰,李刚,林亚鹏(WANG Rong, HE Song, GANG Ruijuan, WANG Qi, TANG Yujie, LIU Feifeng, YANG Jie, LI Gang, LIN Yapeng)
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传统的局部放电模式识别方法识别正确率低,或者训练时间长。文中提出了一种新的局部放电模式识别算法,绘制局部放电信号的PRPS图谱作为输入数据,采用基于稀疏自编码器(sparse autoencoder,SAE)实现对PRPS图谱的特征提取和降维,得到能高度表达原始数据的低维特征空间。利用极限学习机(extremelearning machine,ELM)网络作为分类器,实现对局部放电的分类。利用实验得到的数据样本测试该算法,结果表明该算法不仅模式识别正确率高,并且训练速度快。
何金 +5 more
doaj
机械故障是高压断路器最常见的故障,研究高压断路器机械故障诊断方法对于提高电力系统可靠性具有重要意义。为提高高压断路器机械故障诊断的效率,文中提出一种基于S变换和极限学习机(ELM)的高压断路器机械故障诊断新方法。首先,对高压断路器动作期间产生的振动信号进行S变换处理,获得相应的时—频矩阵;然后,对S变换模值矩阵进行时域和频域划分,计算振动信号在不同时段和频段的局部奇异值,并选择各子矩阵的最大奇异值作为故障诊断的特征向量;最后,采用ELM对高压断路器机械状态进行分类 ...
黄南天, 陈怀金, 林琳, 戚佳金
doaj
Review of Application of Surface Electromyography Signals in Muscle Fatigue Research [PDF]
Muscle fatigue is a physiological phenomenon that occurs when muscles are overused or continuously loaded during exercise or labor. Currently, analyzing the fatigue mechanism is still a complex and multi-layered research problem.
FANG Boru, QIU Dawei, BAI Yang, LIU Jing
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针对内部结构不详、器件参数未知的复杂电子电路电磁脉冲响应建模这一难点问题,笔者采用NARX神经网络建立动力学模型,并提出了采用正弦波扫频信号及其电路响应作为训练数据的方法,同时给出了NARX神经网络建模的理论基础及设计步骤,证明了集总参数电路响应模型可用NARX神经网络所建立的动力学模型替代,从而得到了基于数据的电子电路电磁脉冲响应建模方法。运用ADS软件完成滤波器电路及射频放大电路的设计与仿真,建立NARX神经网络模型并得到了较好的预测效果,验证了该方法适用于集总参数电路的电磁脉冲响应预测 ...
吴启蒙 +4 more
doaj
在立铣刀铣削过程中,由于工件较硬、切削深度较大、采用摆线铣加工方式使刀具磨损较快、空刀段较多,无法准确识别刀具磨损状态。针对这种情况,提出了一种利用深度约束变分自编码器(deep‑constrained variational auto‑encoder,简称DCVAE)和极限学习机(extreme learning machine,简称ELM)的刀具磨损状态识别方法。首先,将电流有效值信号、加速度信号和声压信号进行融合,将其转化为三维彩色图像;其次,采用DCVAE模型对彩色图像中包含的数据进行降维处理 ...
doaj +1 more source
Non destructive detection of kiwifruit sugar content based on improved WOA-LSSVM and hyperspectral analysis [PDF]
Objective: Addressing the issues of poor accuracy and low efficiency in non-destructive testing methods for kiwifruit sugar content. Methods: Proposing a non-destructive testing method for kiwifruit sugar content that combined hyperspectral detection ...
LI Rulin +3 more
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Soft-sensor modeling of silicon content in hot metal based on sparse robust LS-SVR and multi-objective optimization [PDF]
To solve the problem that the parameter of silicon content ([Si]) in hot mental is difficult to be directly detected and obtained by manual analysis with large time delay, a method of sparse and robust least squares support vector regression (R-S-LS-SVR)
GUO Dong-wei, ZHOU Ping
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