Analysis of long-term EEG signals needs that it be segmented into pseudo stationary epochs. That work is done by regarding to statistical characteristics of a signal such as amplitude and frequency. Time series measur...Analysis of long-term EEG signals needs that it be segmented into pseudo stationary epochs. That work is done by regarding to statistical characteristics of a signal such as amplitude and frequency. Time series measured in real world is frequently non-stationary and to extract important information from the measured time series it is significant to utilize a filter or smoother as a pre-processing step. In the proposed approach, the signal is initially filtered by Moving Average (MA) or Savitzky-Golay filter to attenuate its short-term variations. Then, changes of the amplitude or frequency of the signal is calculated by Modified Varri method which is an acceptable algorithm for segmenting a signal. By using synthetic and real EEG data, the proposed methods are compared with original approach (simple Modified Varri). The simulation results indicate the absolute advantage of the proposed methods.展开更多
为解决汽车半主动悬架(Semi-Active Suspension,SAS)与电动助力转向(Electric Power Steering,EPS)集成系统在线故障诊断的问题,提出将小波分析方法应用到SAS与EPS集成系统传感器和ECU的故障诊断中。首先根据故障状态下传感器和ECU输出...为解决汽车半主动悬架(Semi-Active Suspension,SAS)与电动助力转向(Electric Power Steering,EPS)集成系统在线故障诊断的问题,提出将小波分析方法应用到SAS与EPS集成系统传感器和ECU的故障诊断中。首先根据故障状态下传感器和ECU输出电压信号的突变特性,利用小波分析奇异性检测原理检测出突变信息。随后为能更精确地检测出突变信息,先使用小波阈值法对电压信号消噪,再对消噪后的电压信号进行检测。最后以SAS与EPS集成系统中扭矩传感器和ECU故障诊断为例进行试验研究。结果表明,小波分析方法能有效抑制信号噪声,并准确检测出故障和故障发生时刻,对集成控制系统的安全运行及故障诊断具有重要的工程应用意义。展开更多
Salicylic acid(SA)plays a pivotal role in plant response to biotic and abiotic stress.Several core SA signaling regulators and key proteins in SA biosynthesis have been well characterized.However,much remains unknown ...Salicylic acid(SA)plays a pivotal role in plant response to biotic and abiotic stress.Several core SA signaling regulators and key proteins in SA biosynthesis have been well characterized.However,much remains unknown about the origin,evolution,and early diversification of core elements in plant SA signaling and biosynthesis.In this study,we identified 10 core protein families in SA signaling and biosynthesis across green plant lineages.We found that the key SA signaling receptors,the nonexpresser of pathogenesis-related(NPR)proteins,originated in the most recent common ancestor(MRCA)of land plants and formed divergent groups in the ancestor of seed plants.However,key transcription factors for SA signaling,TGACG motif-binding proteins(TGAs),originated in the MRCA of streptophytes,arguing for the stepwise evolution of core SA signaling in plants.Different from the assembly of the core SA signaling pathway in the ancestor of seed plants,SA exists extensively in green plants,including chlorophytes and streptophyte algae.However,the full isochorismate synthase(ICS)-based SA synthesis pathway was first assembled in the MRCA of land plants.We further revealed that the ancient abnormal inflorescence meristem 1(AIM1)-basedβ-oxidation pathway is crucial for the biosynthesis of SA in chlorophyte algae,and this biosynthesis pathway may have facilitated the adaptation of early-diverging green algae to the high-light-intensity environment on land.Taken together,our findings provide significant insights into the early evolution and diversification of plant SA signaling and biosynthesis pathways,highlighting a crucial role of SA in stress tolerance during plant terrestrialization.展开更多
文摘Analysis of long-term EEG signals needs that it be segmented into pseudo stationary epochs. That work is done by regarding to statistical characteristics of a signal such as amplitude and frequency. Time series measured in real world is frequently non-stationary and to extract important information from the measured time series it is significant to utilize a filter or smoother as a pre-processing step. In the proposed approach, the signal is initially filtered by Moving Average (MA) or Savitzky-Golay filter to attenuate its short-term variations. Then, changes of the amplitude or frequency of the signal is calculated by Modified Varri method which is an acceptable algorithm for segmenting a signal. By using synthetic and real EEG data, the proposed methods are compared with original approach (simple Modified Varri). The simulation results indicate the absolute advantage of the proposed methods.
文摘为解决汽车半主动悬架(Semi-Active Suspension,SAS)与电动助力转向(Electric Power Steering,EPS)集成系统在线故障诊断的问题,提出将小波分析方法应用到SAS与EPS集成系统传感器和ECU的故障诊断中。首先根据故障状态下传感器和ECU输出电压信号的突变特性,利用小波分析奇异性检测原理检测出突变信息。随后为能更精确地检测出突变信息,先使用小波阈值法对电压信号消噪,再对消噪后的电压信号进行检测。最后以SAS与EPS集成系统中扭矩传感器和ECU故障诊断为例进行试验研究。结果表明,小波分析方法能有效抑制信号噪声,并准确检测出故障和故障发生时刻,对集成控制系统的安全运行及故障诊断具有重要的工程应用意义。
基金National Key Research and Development Program of China(2021 YFF1000404)National Natural Science Foun-dation of China(32130096)+1 种基金Central Public-interest Scientific Insti-tution Basal Research Fund(Y2022QC14)K.Y.was supported by the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences.
文摘Salicylic acid(SA)plays a pivotal role in plant response to biotic and abiotic stress.Several core SA signaling regulators and key proteins in SA biosynthesis have been well characterized.However,much remains unknown about the origin,evolution,and early diversification of core elements in plant SA signaling and biosynthesis.In this study,we identified 10 core protein families in SA signaling and biosynthesis across green plant lineages.We found that the key SA signaling receptors,the nonexpresser of pathogenesis-related(NPR)proteins,originated in the most recent common ancestor(MRCA)of land plants and formed divergent groups in the ancestor of seed plants.However,key transcription factors for SA signaling,TGACG motif-binding proteins(TGAs),originated in the MRCA of streptophytes,arguing for the stepwise evolution of core SA signaling in plants.Different from the assembly of the core SA signaling pathway in the ancestor of seed plants,SA exists extensively in green plants,including chlorophytes and streptophyte algae.However,the full isochorismate synthase(ICS)-based SA synthesis pathway was first assembled in the MRCA of land plants.We further revealed that the ancient abnormal inflorescence meristem 1(AIM1)-basedβ-oxidation pathway is crucial for the biosynthesis of SA in chlorophyte algae,and this biosynthesis pathway may have facilitated the adaptation of early-diverging green algae to the high-light-intensity environment on land.Taken together,our findings provide significant insights into the early evolution and diversification of plant SA signaling and biosynthesis pathways,highlighting a crucial role of SA in stress tolerance during plant terrestrialization.