Bioelectrical signals,especially electroencephalography(EEG)and electrocardiography(ECG),are indispensable for health assessment.However,achieving high-quality signal acquisition while ensuring long-term stability rem...Bioelectrical signals,especially electroencephalography(EEG)and electrocardiography(ECG),are indispensable for health assessment.However,achieving high-quality signal acquisition while ensuring long-term stability remains a significant challenge in the bioelectrical electrodes.Herein,a cholinium-based eutectogel(ChCl-egel)is reported for dynamic ECG and EEG monitoring.By utilizing hydrogen bonding of deep eutectic solvents(DESs)to modulate conductivity,the ChCl-egel realizes an ultra-low skin impedance(4.7 kΩat 10 Hz)with reliable stability.Additionally,the ChCl-egel exhibits excellent conformal contact and biocompatibility.During ECG monitoring,the ChCl-egel offers an 8 dB improvement in signal-to-noise ratio(SNR)compared to commercial ECG electrodes(3 M,Red Dot)over 48-hour period,enabling dynamic record under high-intensity exercises.In an 18-hour steadystate visual evoked potential(SSVEP)experiment,it can match the scalp impedance of commercial gel and support longer record.With high-quality dynamic monitoring capability,the ChCl-egel provides a promising solution for long-term bioelectrical signal acquisition.展开更多
Owing to the lack of a direct link with the operations in short-range air combat,conventional aircraft flying qualities criteria are inappropriate to guide the design of a task-tailored flight control law.By applying ...Owing to the lack of a direct link with the operations in short-range air combat,conventional aircraft flying qualities criteria are inappropriate to guide the design of a task-tailored flight control law.By applying the mission-oriented flying qualities evaluation approach,various aircraft with different control law parameters are evaluated on a ground-based simulator.This paper compares the evaluation results with several conventional flying qualities criteria,and discusses the appropriate parameter combination to reflect the flying qualities requirements of short-range air combat.The comparison and analysis show that a short-range air combat mission requires a higher minimum short period mode natural frequency and a smaller maximum roll mode time constant,and allows a lower minimum pitch attitude bandwidth and a higher maximum short period mode damp ratio than those of conventional flying qualities criteria.Furthermore,a combination of the pitch attitude bandwidth,the pitch attitude magnitude at the bandwidth frequency,and the pitch attitude transfer function gain can define the flying qualities requirements of short-range air combat.The new metric can successfully predict the flying quality levels of aircraft in a short-range air combat mission.展开更多
基金supported by the National Science and Technology Major Project Fund of China under Grant 2025ZD0215600the General Program of Natural Science Foundation of Beijing Grants No.7242271+5 种基金the National Natural Science Foundation of China(NSFC)under grant No.92472106,52325312,52421001,52388201Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park,under grant No.Z231100006023020Youth Program of NSFC Grants No.12102224Shanghai Special Fund for Industrial High Quality Development:Pioneering Industries Innovation and Development Projects Grants No.2024-GZL-RGZN-02026Beijing University of Posts and Telecommunications Excellent Ph.D.Students Foundation(grant No.CX20241089)the Start-up Funding of Beijing University of Posts and Telecommunications(grant No.500422817 and 510224039).
文摘Bioelectrical signals,especially electroencephalography(EEG)and electrocardiography(ECG),are indispensable for health assessment.However,achieving high-quality signal acquisition while ensuring long-term stability remains a significant challenge in the bioelectrical electrodes.Herein,a cholinium-based eutectogel(ChCl-egel)is reported for dynamic ECG and EEG monitoring.By utilizing hydrogen bonding of deep eutectic solvents(DESs)to modulate conductivity,the ChCl-egel realizes an ultra-low skin impedance(4.7 kΩat 10 Hz)with reliable stability.Additionally,the ChCl-egel exhibits excellent conformal contact and biocompatibility.During ECG monitoring,the ChCl-egel offers an 8 dB improvement in signal-to-noise ratio(SNR)compared to commercial ECG electrodes(3 M,Red Dot)over 48-hour period,enabling dynamic record under high-intensity exercises.In an 18-hour steadystate visual evoked potential(SSVEP)experiment,it can match the scalp impedance of commercial gel and support longer record.With high-quality dynamic monitoring capability,the ChCl-egel provides a promising solution for long-term bioelectrical signal acquisition.
文摘Owing to the lack of a direct link with the operations in short-range air combat,conventional aircraft flying qualities criteria are inappropriate to guide the design of a task-tailored flight control law.By applying the mission-oriented flying qualities evaluation approach,various aircraft with different control law parameters are evaluated on a ground-based simulator.This paper compares the evaluation results with several conventional flying qualities criteria,and discusses the appropriate parameter combination to reflect the flying qualities requirements of short-range air combat.The comparison and analysis show that a short-range air combat mission requires a higher minimum short period mode natural frequency and a smaller maximum roll mode time constant,and allows a lower minimum pitch attitude bandwidth and a higher maximum short period mode damp ratio than those of conventional flying qualities criteria.Furthermore,a combination of the pitch attitude bandwidth,the pitch attitude magnitude at the bandwidth frequency,and the pitch attitude transfer function gain can define the flying qualities requirements of short-range air combat.The new metric can successfully predict the flying quality levels of aircraft in a short-range air combat mission.
