Sleep spindle is the characteristic waveform of electroencephalogram (EEG) which is important for clinical diagnosis. In this study, an automatic sleep spindle detection method was developed. The EEG signals were reco...Sleep spindle is the characteristic waveform of electroencephalogram (EEG) which is important for clinical diagnosis. In this study, an automatic sleep spindle detection method was developed. The EEG signals were recorded based on the standard polysomnogram (PSG) measurement. A preprocessing procedure is introduced to exclude the unnecessary data segments and normalized the necessary data segments. Complex demodulation method is adopted to detect the candidate sleep spindle waveforms and calculate the features. The sleep spindles are recognized based on a decision tree model. Finally, the detected sleep spindles were utilized to amend the sleep stage recognition results. The sleep EEG data from 3 patients with sleep disorders were analyzed. The obtained results showed that the detected sleep spindles in EEG signal improved the accuracy of sleep stage recognition.展开更多
基于过完备字典的振动信号稀疏表示是滚动轴承信号研究的新热点。提出一种改进MOD字典学习的算法,并用于滚动轴承振动信号的稀疏表示。该方法基于MOD(Method of Optimal Direction)训练学习过程,通过构造分段重叠训练矩阵,能够得到更为...基于过完备字典的振动信号稀疏表示是滚动轴承信号研究的新热点。提出一种改进MOD字典学习的算法,并用于滚动轴承振动信号的稀疏表示。该方法基于MOD(Method of Optimal Direction)训练学习过程,通过构造分段重叠训练矩阵,能够得到更为稀疏的变换系数。相对DCT、FFT和未改进的处理方法,该方法得到的变换系数更稀疏。将该方法应用到基于压缩感知的滚动轴承振动信号处理,在相同的重构误差范围内,该方法所需要的观测数更少,计算量更小。展开更多
ZnO films were deposited on glass substrates by means of a metal organic decomposition (MOD) method. We investigated the effect of annealing temperature, time and the number of laminated layers on the film structure o...ZnO films were deposited on glass substrates by means of a metal organic decomposition (MOD) method. We investigated the effect of annealing temperature, time and the number of laminated layers on the film structure on the basis of X-ray diffraction measurements. We found the optimum conditions of the temperature and the time to be 600°C and 40 minutes for the preparation, respectively. In addition, the layer-by-layer forming was not found to degrade the film from viewpoint of X-ray line width.展开更多
文摘Sleep spindle is the characteristic waveform of electroencephalogram (EEG) which is important for clinical diagnosis. In this study, an automatic sleep spindle detection method was developed. The EEG signals were recorded based on the standard polysomnogram (PSG) measurement. A preprocessing procedure is introduced to exclude the unnecessary data segments and normalized the necessary data segments. Complex demodulation method is adopted to detect the candidate sleep spindle waveforms and calculate the features. The sleep spindles are recognized based on a decision tree model. Finally, the detected sleep spindles were utilized to amend the sleep stage recognition results. The sleep EEG data from 3 patients with sleep disorders were analyzed. The obtained results showed that the detected sleep spindles in EEG signal improved the accuracy of sleep stage recognition.
文摘基于过完备字典的振动信号稀疏表示是滚动轴承信号研究的新热点。提出一种改进MOD字典学习的算法,并用于滚动轴承振动信号的稀疏表示。该方法基于MOD(Method of Optimal Direction)训练学习过程,通过构造分段重叠训练矩阵,能够得到更为稀疏的变换系数。相对DCT、FFT和未改进的处理方法,该方法得到的变换系数更稀疏。将该方法应用到基于压缩感知的滚动轴承振动信号处理,在相同的重构误差范围内,该方法所需要的观测数更少,计算量更小。
文摘ZnO films were deposited on glass substrates by means of a metal organic decomposition (MOD) method. We investigated the effect of annealing temperature, time and the number of laminated layers on the film structure on the basis of X-ray diffraction measurements. We found the optimum conditions of the temperature and the time to be 600°C and 40 minutes for the preparation, respectively. In addition, the layer-by-layer forming was not found to degrade the film from viewpoint of X-ray line width.
