Competition-based-winners-take-all(WTA)networks play a crucial role in multi-agent systems.However,existing WTA networks either neglect the impact of noise or only consider simple forms,such as constant noise.In pract...Competition-based-winners-take-all(WTA)networks play a crucial role in multi-agent systems.However,existing WTA networks either neglect the impact of noise or only consider simple forms,such as constant noise.In practice,noises often exhibit time-varying and nonlinear characteristics,which can be modeled using nonlinear functions and approximated by high-order polynomials.Such noises pose significant challenges for current WTA networks,limiting their practical applications.To address this,a WTA network with noise characteristics captured(WTA-NCC)is proposed in this article.Theoretical analyses demonstrate that the residual error of the proposed WTANCC network converges to zero globally,while simulation results confirm its robustness against polynomial noises.Additionally,a WTA coordination model is constructed by integrating the proposed network with a consensus estimator to achieve multi-agent tracking tasks.Finally,simulations and physical experiments are conducted further to demonstrate the validity and practicality of the WTA coordination model.展开更多
This study investigated the effect of transcranial direct current stimulation（t DCS） polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive task...This study investigated the effect of transcranial direct current stimulation（t DCS） polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive tasks. Thirty healthy participants with no neurological disorders were recruited to participate in this study. Participants were randomly allocated into active or control condition. For the active condition, t DCS intensity was 2 m A with stimulation applied for 15 minutes to the right hemisphere（t DCS condition）. For the sham control, electrodes were placed in the same position, but the stimulator was turned off after 30 seconds（sham condition）. The tapping and tracking task tests were performed before and after for both conditions. Univariate analysis revealed significant difference only in the tracking task. For direct comparison of both tasks within each group, the tracking task had significantly higher Z score than the tapping task in the t DCS group（P 〈 0.05）. Thus, our study indicates that stimulation of the right hemisphere using t DCS can effectively improve visuomotor（tracking） task over simple repetitive（tapping） task.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 in part by the National Natural Science Foundation of China(62176109,62476115)in part by the Fundamental Research Funds for the Central Universities(lzuibky-2023-ey07)+1 种基金in part by the Youth and Middle-aged Scientific Research Foundation of Qinghai Normal University(2020QZR012)in part by the Supercomputing Center of Lanzhou University.
文摘Competition-based-winners-take-all(WTA)networks play a crucial role in multi-agent systems.However,existing WTA networks either neglect the impact of noise or only consider simple forms,such as constant noise.In practice,noises often exhibit time-varying and nonlinear characteristics,which can be modeled using nonlinear functions and approximated by high-order polynomials.Such noises pose significant challenges for current WTA networks,limiting their practical applications.To address this,a WTA network with noise characteristics captured(WTA-NCC)is proposed in this article.Theoretical analyses demonstrate that the residual error of the proposed WTANCC network converges to zero globally,while simulation results confirm its robustness against polynomial noises.Additionally,a WTA coordination model is constructed by integrating the proposed network with a consensus estimator to achieve multi-agent tracking tasks.Finally,simulations and physical experiments are conducted further to demonstrate the validity and practicality of the WTA coordination model.
文摘This study investigated the effect of transcranial direct current stimulation（t DCS） polarity depending on lateralized function of task property in normal individuals performing visuomotor and simple repetitive tasks. Thirty healthy participants with no neurological disorders were recruited to participate in this study. Participants were randomly allocated into active or control condition. For the active condition, t DCS intensity was 2 m A with stimulation applied for 15 minutes to the right hemisphere（t DCS condition）. For the sham control, electrodes were placed in the same position, but the stimulator was turned off after 30 seconds（sham condition）. The tapping and tracking task tests were performed before and after for both conditions. Univariate analysis revealed significant difference only in the tracking task. For direct comparison of both tasks within each group, the tracking task had significantly higher Z score than the tapping task in the t DCS group（P 〈 0.05）. Thus, our study indicates that stimulation of the right hemisphere using t DCS can effectively improve visuomotor（tracking） task over simple repetitive（tapping） task.
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.
