To investigate whether and how manual acupuncture（MA） modulates brain activities,we design an experiment where acupuncture at acupoint ST36 of the right leg is used to obtain electroencephalograph（EEG） signals in ...To investigate whether and how manual acupuncture（MA） modulates brain activities,we design an experiment where acupuncture at acupoint ST36 of the right leg is used to obtain electroencephalograph（EEG） signals in healthy subjects.We adopt the autoregressive（AR） Burg method to estimate the power spectrum of EEG signals and analyze the relative powers in delta（0 Hz-4 Hz）,theta（4 Hz-8 Hz）,alpha（8 Hz-13 Hz）,and beta（13 Hz-30 Hz） bands.Our results show that MA at ST36 can significantly increase the EEG slow wave relative power（delta band） and reduce the fast wave relative powers（alpha and beta bands）,while there are no statistical differences in theta band relative power between different acupuncture states.In order to quantify the ratio of slow to fast wave EEG activity,we compute the power ratio index.It is found that the MA can significantly increase the power ratio index,especially in frontal and central lobes.All the results highlight the modulation of brain activities with MA and may provide potential help for the clinical use of acupuncture.The proposed quantitative method of acupuncture signals may be further used to make MA more standardized.展开更多
吊舱稳定平台在无人直升机电力巡线中发挥着重要作用。为了提高巡线质量和效率,克服自动跟踪单一模式下多源扰动导致的光学载荷视轴对目标的跟踪丢失,提出了一种基于自动/手动混合模式的吊舱稳定平台控制策略。通过组合使用基于POS(Posi...吊舱稳定平台在无人直升机电力巡线中发挥着重要作用。为了提高巡线质量和效率,克服自动跟踪单一模式下多源扰动导致的光学载荷视轴对目标的跟踪丢失,提出了一种基于自动/手动混合模式的吊舱稳定平台控制策略。通过组合使用基于POS(Position and Orientation System)的位置和姿态信息的自动跟踪控制模式和基于人工手柄操作的手动跟踪控制模式,当目标跟踪丢失时利用手动模式及时对自动跟踪进行校正,实现吊舱稳定平台载荷视轴对电力线路的长时高精度稳定跟踪。根据控制策略,设计了基于DSP和FPGA的三环复合伺服控制系统,通过仿真分析得到将手动控制设置在速率回路是最佳方案的结论。通过实际线路飞行实验对控制方法进行了验证,结果表明:基于自动/手动混合模式的平台控制对目标跟踪灵活准确,实现了无人机多传感器系统对电力线路的高效高精度数据采集。展开更多
基金Project supported by the Key Program of the National Natural Science Foundation of China (Grant No. 50537030)the National Natural Science Foundation of China (Grant Nos. 61072012 and 61172009)+1 种基金the Young Scientists Fund of the National Natural Science Foundation of China (Grant Nos. 61104032 and 60901035)the Tianjin Municipal Natural Science Foundation (Grant No. 12JCZDJC21100)
文摘To investigate whether and how manual acupuncture（MA） modulates brain activities,we design an experiment where acupuncture at acupoint ST36 of the right leg is used to obtain electroencephalograph（EEG） signals in healthy subjects.We adopt the autoregressive（AR） Burg method to estimate the power spectrum of EEG signals and analyze the relative powers in delta（0 Hz-4 Hz）,theta（4 Hz-8 Hz）,alpha（8 Hz-13 Hz）,and beta（13 Hz-30 Hz） bands.Our results show that MA at ST36 can significantly increase the EEG slow wave relative power（delta band） and reduce the fast wave relative powers（alpha and beta bands）,while there are no statistical differences in theta band relative power between different acupuncture states.In order to quantify the ratio of slow to fast wave EEG activity,we compute the power ratio index.It is found that the MA can significantly increase the power ratio index,especially in frontal and central lobes.All the results highlight the modulation of brain activities with MA and may provide potential help for the clinical use of acupuncture.The proposed quantitative method of acupuncture signals may be further used to make MA more standardized.
文摘吊舱稳定平台在无人直升机电力巡线中发挥着重要作用。为了提高巡线质量和效率,克服自动跟踪单一模式下多源扰动导致的光学载荷视轴对目标的跟踪丢失,提出了一种基于自动/手动混合模式的吊舱稳定平台控制策略。通过组合使用基于POS(Position and Orientation System)的位置和姿态信息的自动跟踪控制模式和基于人工手柄操作的手动跟踪控制模式,当目标跟踪丢失时利用手动模式及时对自动跟踪进行校正,实现吊舱稳定平台载荷视轴对电力线路的长时高精度稳定跟踪。根据控制策略,设计了基于DSP和FPGA的三环复合伺服控制系统,通过仿真分析得到将手动控制设置在速率回路是最佳方案的结论。通过实际线路飞行实验对控制方法进行了验证,结果表明:基于自动/手动混合模式的平台控制对目标跟踪灵活准确,实现了无人机多传感器系统对电力线路的高效高精度数据采集。
