Si-PIN photodetectors having features such as low cost,small size,low weight,low voltage,and low power consumption are widely used as radiation detectors in electronic personal dosimeters(EPDs).The technical parameter...Si-PIN photodetectors having features such as low cost,small size,low weight,low voltage,and low power consumption are widely used as radiation detectors in electronic personal dosimeters(EPDs).The technical parameters of EPDs based on the Si-PIN photodetectors include photon energy response(PER),angular response,inherent error,and dose rate linearity.Among them,PER is a key parameter for evaluation of EPD measurement accuracy.At present,owing to the limitations of volume,power consumption,and EPD cost,the PER is usually corrected by a combination of single-channel counting techniques and filtering material methods.However,the above-mentioned methods have problems such as poor PER and low measurement accuracy.To solve such problems,in this study,a 1024-channel spectrometry system using a Si-PIN photodetector was developed and fullspectrum measurement in the reference radiation fields was conducted for radiation protection.The measurement results using the few-channel spectroscopy dose method showed that the PER could be controlled within±14%and±2%under the conditions of two and three energy intervals,respectively,with different channel numbers.The PER measured at 0°angle of radiation incidence meets the-29%to+67%requirements of IEC 61526:2010.Meanwhile,the channel number and counts-to-dose conversion factors formed in the experiment can be integrated into an EPD.展开更多
Background Electroencephalography(EEG)has gained popularity in various types of biomedical applications as a signal source that can be easily acquired and conveniently analyzed.However,owing to a complex scalp electri...Background Electroencephalography(EEG)has gained popularity in various types of biomedical applications as a signal source that can be easily acquired and conveniently analyzed.However,owing to a complex scalp electrical environment,EEG is often polluted by diverse artifacts,with electromyography artifacts being the most difficult to remove.In particular,for ambulatory EEG devices with a restricted number of channels,dealing with muscle artifacts is a challenge.Methods In this study,we propose a simple but effective novel scheme that combines singular spectrum analysis(SSA)and canonical correlation analysis(CCA)algorithms for single-channel problems and then extend it to a few channel case by adding additional combining and dividing operations to channels.Results We evaluated our proposed framework on both semi-simulated and real-life data and compared it with some state-of-the art methods.The results demonstrate this novel framework's superior performance in both single-channel and few-channel cases.Conclusions This promising approach,based on its effectiveness and low time cost,is suitable for real-world biomedical signal processing applications.展开更多
基金This work was partly supported by the National Key Scientific Instruments to Develop Dedicated Program(Nos.2013YQ090811 and 2016YFF0103800)the National Key Research and Development Program(No.2017YFF0211100).
文摘Si-PIN photodetectors having features such as low cost,small size,low weight,low voltage,and low power consumption are widely used as radiation detectors in electronic personal dosimeters(EPDs).The technical parameters of EPDs based on the Si-PIN photodetectors include photon energy response(PER),angular response,inherent error,and dose rate linearity.Among them,PER is a key parameter for evaluation of EPD measurement accuracy.At present,owing to the limitations of volume,power consumption,and EPD cost,the PER is usually corrected by a combination of single-channel counting techniques and filtering material methods.However,the above-mentioned methods have problems such as poor PER and low measurement accuracy.To solve such problems,in this study,a 1024-channel spectrometry system using a Si-PIN photodetector was developed and fullspectrum measurement in the reference radiation fields was conducted for radiation protection.The measurement results using the few-channel spectroscopy dose method showed that the PER could be controlled within±14%and±2%under the conditions of two and three energy intervals,respectively,with different channel numbers.The PER measured at 0°angle of radiation incidence meets the-29%to+67%requirements of IEC 61526:2010.Meanwhile,the channel number and counts-to-dose conversion factors formed in the experiment can be integrated into an EPD.
基金Supported by the National Natural Science Foundation of China(61922075)the USTC Research Funds of the Double First-Class Initiative(YD2100002004).
文摘Background Electroencephalography(EEG)has gained popularity in various types of biomedical applications as a signal source that can be easily acquired and conveniently analyzed.However,owing to a complex scalp electrical environment,EEG is often polluted by diverse artifacts,with electromyography artifacts being the most difficult to remove.In particular,for ambulatory EEG devices with a restricted number of channels,dealing with muscle artifacts is a challenge.Methods In this study,we propose a simple but effective novel scheme that combines singular spectrum analysis(SSA)and canonical correlation analysis(CCA)algorithms for single-channel problems and then extend it to a few channel case by adding additional combining and dividing operations to channels.Results We evaluated our proposed framework on both semi-simulated and real-life data and compared it with some state-of-the art methods.The results demonstrate this novel framework's superior performance in both single-channel and few-channel cases.Conclusions This promising approach,based on its effectiveness and low time cost,is suitable for real-world biomedical signal processing applications.
