目的:分析下肢康复机器人联合悬吊运动训练对脑卒中患者下肢功能和日常生活能力的影响。方法:将2022年1月—2023年7月清远市人民医院收治的脑卒中患者90例作为本次观察对象,采取随机数字表法分成三组:A组(下肢康复机器人)、B组(悬吊运...目的:分析下肢康复机器人联合悬吊运动训练对脑卒中患者下肢功能和日常生活能力的影响。方法:将2022年1月—2023年7月清远市人民医院收治的脑卒中患者90例作为本次观察对象,采取随机数字表法分成三组:A组(下肢康复机器人)、B组(悬吊运动训练)、C组(下肢康复机器人联合悬吊运动训练),每组30例。比较三组训练后下肢Fugl-Meyer评估表(Fugl-Meyer assessment scale,FMA)评分、伯格平衡量表(Berg balance scale,BBS)评分、Holden功能性步行量表(functional amby iation category scale,FAC)评分、6分钟步行试验(6 min walk test,6MWT)及改良Barthel指数(modified Barthel index,MBI)、美国国立卫生研究院卒中量表(national institutes of health stroke scale,NIHSS)评分。结果:训练前,三组下肢FMA、BBS、FAC评分、6MWT、MBI、NIHSS评分比较,差异均无统计学意义(P>0.05);训练后,C组下肢FMA、BBS、FAC、MBI评分均明显更高于A组、B组,6MWT长于A组、B组,NIHSS评分低于A组、B组,差异均有统计学意义(P<0.05);A组、B组各项指标比较,差异均无统计学意义(P>0.05)。结论:在脑卒中后对患者采取下肢康复机器人联合悬吊运动训练,可提高患者下肢运动功能与步行能力,增强患者平衡与下肢运动功能,并改善神经功能,提高生活质量,促进身体康复。展开更多
To solve the problem of multi-target hunting by an unmanned surface vehicle(USV)fleet,a hunting algorithm based on multi-agent reinforcement learning is proposed.Firstly,the hunting environment and kinematic model wit...To solve the problem of multi-target hunting by an unmanned surface vehicle(USV)fleet,a hunting algorithm based on multi-agent reinforcement learning is proposed.Firstly,the hunting environment and kinematic model without boundary constraints are built,and the criteria for successful target capture are given.Then,the cooperative hunting problem of a USV fleet is modeled as a decentralized partially observable Markov decision process(Dec-POMDP),and a distributed partially observable multitarget hunting Proximal Policy Optimization(DPOMH-PPO)algorithm applicable to USVs is proposed.In addition,an observation model,a reward function and the action space applicable to multi-target hunting tasks are designed.To deal with the dynamic change of observational feature dimension input by partially observable systems,a feature embedding block is proposed.By combining the two feature compression methods of column-wise max pooling(CMP)and column-wise average-pooling(CAP),observational feature encoding is established.Finally,the centralized training and decentralized execution framework is adopted to complete the training of hunting strategy.Each USV in the fleet shares the same policy and perform actions independently.Simulation experiments have verified the effectiveness of the DPOMH-PPO algorithm in the test scenarios with different numbers of USVs.Moreover,the advantages of the proposed model are comprehensively analyzed from the aspects of algorithm performance,migration effect in task scenarios and self-organization capability after being damaged,the potential deployment and application of DPOMH-PPO in the real environment is verified.展开更多
A nickel hexacyanoferrate(NiHCF)film electrode was prepared with NiHCF,conductive carbon black,and polyvinylidene difluoride,which was coated on graphite plate substrate for selective extraction of Cs^(+)ions by using...A nickel hexacyanoferrate(NiHCF)film electrode was prepared with NiHCF,conductive carbon black,and polyvinylidene difluoride,which was coated on graphite plate substrate for selective extraction of Cs^(+)ions by using electrochemically switched ion exchange(ESIX)technology.A potential-responsive ionpump system for efficient extraction of Cs+ions was designed,and the effect of wet film thicknesses,charging modes,flow rates,and chamber widths on Cs+ions extraction performance was investigated.In the system,the adsorption capacity and removal percentage of Cs^(+)ions on the NiHCF film electrode reached as high as 147.69 mg·g^(-1)and 92.47%,respectively.Furthermore,the NiHCF film electrode showed high selectivity for Cs^(+)ions and stability.After seven cycles of adsorption/desorption,the desorption percentage could reach about 100%.The excellent Cs^(+)extraction performance should be attributed to the strong driving force produced by the potential-responsive ion-pumping effect in the ESIX process,as well as the low ion transfer resistance of the film electrode which is caused by the special crystal structure of NiHCF.In addition,the NiHCF film electrode was implemented to work together with the bismuth oxybromide(BiOBr)film electrode to accomplish the simultaneous extraction of Cs^(+)and Br^(-).And the adsorption capacity and removal percentage of Br^(-)ions on the BiOBr film electrode reached 69.53 mg·g^(-1)and 77.32%,correspondingly.It is expected that such a potential-responsive ion-pump system based on NiHCF and BiOBr film electrodes could be used for the selective extraction and concentration of Cs^(+)and Br^(-)ions from salt lake brine.展开更多
The New Vacuum Solar Telescope(NVST) is a one meter vacuum solar telescope that aims to observe fine structures on the Sun. The main goals of NVST are high resolution imaging and spectral observations, including measu...The New Vacuum Solar Telescope(NVST) is a one meter vacuum solar telescope that aims to observe fine structures on the Sun. The main goals of NVST are high resolution imaging and spectral observations, including measurements of the solar magnetic field. NVST is the primary ground-based facility used by the Chinese solar research community in this solar cycle. It is located by Fuxian Lake in southwest China, where the seeing is good enough to perform high resolution observations. We first introduce the general conditions at the Fuxian Solar Observatory and the primary science cases of NVST. Then, the basic structures of this telescope and instruments are described in detail. Finally, some typical high resolution data of the solar photosphere and chromosphere are also shown.展开更多
The Multi-wavelength Spectrometer is a medium-dispersion(R^130 000)grating spectrometer installed on the New Vacuum Solar Telescope at the Fuxian Solar Observatory,Yunnan Astronomical Observatory,Chinese Academy of Sc...The Multi-wavelength Spectrometer is a medium-dispersion(R^130 000)grating spectrometer installed on the New Vacuum Solar Telescope at the Fuxian Solar Observatory,Yunnan Astronomical Observatory,Chinese Academy of Sciences.It is designed to accurately observe the velocity and magnetic fields of the Sun.The present configuration of this spectrometer allows us to simultaneously observe three different solar spectral lines.This work is dedicated to showing the first observations carried out in both the Hαand Ca II 8542 A lines.We give a detailed description of the data reduction process,focusing on the retrieval of a flat field from the high-resolution spectral data.Two different methods are also performed and compared to eliminate the residual fringe in the reduced data.The real spectral resolution and instrumental profile are analyzed based on the final results,which indicate that this spectrometer presently satisfies the expected performance and it is ready for further scientific observations.展开更多
The Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China,has been available to the worldwide astronomical community since 2008. It is located at the Gaomeigu site,Lijiang Observatory...The Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China,has been available to the worldwide astronomical community since 2008. It is located at the Gaomeigu site,Lijiang Observatory(LJO), in the southwest of China. The site has very good observational conditions.During its 10-year operation, several instruments have been equipped on the LJT. Astronomers can perform both photometric and spectral observations. The main scientific goals of LJT include recording photometric and spectral evolution of supernovae, reverberation mapping of active galactic nuclei, investigating the physical properties of binary stars and near-earth objects(comets and asteroids), and identification of exoplanets and all kinds of transients. Until now, the masses of 41 high accretion rate black holes have been measured, and more than 168 supernovae have been identified by the LJT. More than 190 papers related to the LJT have been published. In this paper, the general observation conditions of the Gaomeigu site is introduced at first. Then, the structure of the LJT is described in detail, including the optical, mechanical, motion and control system. The specification of all the instruments and some detailed parameters of the YFOSC is also presented. Finally, some important scientific results and future expectations are summarized.展开更多
Aimed at the abominable influences to blind equalization algorithms caused by complex timespace variability existing in underwater acoustic channels, a new selfadjusting decision feedback equalization(DFE) algorithm a...Aimed at the abominable influences to blind equalization algorithms caused by complex timespace variability existing in underwater acoustic channels, a new selfadjusting decision feedback equalization(DFE) algorithm adapting to different underwater acoustic channel environments is proposed by changing its central tap position. Besides, this new algorithm behaves faster convergence speed based on the analysis of equalizers' working rules, which is more suitable to implement communications in different unknown channels. Corresponding results and conclusions are validated by simulations and spot experiments.展开更多
This paper is devoted to the primary spectro-polarimetric observation performed at the New Vacuum Solar Telescope(NVST)of China since 2017,and our aim is to precisely evaluate the real polarimetric accuracy and sensit...This paper is devoted to the primary spectro-polarimetric observation performed at the New Vacuum Solar Telescope(NVST)of China since 2017,and our aim is to precisely evaluate the real polarimetric accuracy and sensitivity of this polarimetry by using full Stokes spectro-polarimetric observations of the photospheric line Fe I 532.4 nm.In the work,we briefly describe the salient characteristic of the NVST as a polarimeter in terms of technology and then characterize its instrumental polarization based on the operation in 2017 and 2019.It is verified that the calibration method utilizing the instrumental polarization calibration unit(ICU)is stable and credible.The calibration accuracy can reach up to 3×10^-3.Based on the scientific observation of NOAA Active Region 12645 on 2017 April 5,we estimate that the residual cross-talk from Stokes I to Stokes Q,U and V,after the instrumental polarization calibration,is about 4×10^-3 on average,which is consistent with the calibration accuracy and close to the photon noise.The polarimetric sensitivity(i.e.,the detection limit)for polarized light is of the order of 10-3 with an integration time over 20 s.Slow modulation rate is indeed an issue for the present system.The present NVST polarimeter is expected to be integrated with a high-order adaptive optics system and a field scanner to realize 2 D vector magnetic field measurements in the following instrumentation update.展开更多
Neurodegeneration and traumatic brain injuries are leading causes of disability and present an enormous disease burden both in terms of patient suffering and healthcare cost.Treatment of brain lesions remains as a maj...Neurodegeneration and traumatic brain injuries are leading causes of disability and present an enormous disease burden both in terms of patient suffering and healthcare cost.Treatment of brain lesions remains as a major challenge in medicine largely because of the limited regenerative capacity of the adult brain.Neural展开更多
文摘目的:分析下肢康复机器人联合悬吊运动训练对脑卒中患者下肢功能和日常生活能力的影响。方法:将2022年1月—2023年7月清远市人民医院收治的脑卒中患者90例作为本次观察对象,采取随机数字表法分成三组:A组(下肢康复机器人)、B组(悬吊运动训练)、C组(下肢康复机器人联合悬吊运动训练),每组30例。比较三组训练后下肢Fugl-Meyer评估表(Fugl-Meyer assessment scale,FMA)评分、伯格平衡量表(Berg balance scale,BBS)评分、Holden功能性步行量表(functional amby iation category scale,FAC)评分、6分钟步行试验(6 min walk test,6MWT)及改良Barthel指数(modified Barthel index,MBI)、美国国立卫生研究院卒中量表(national institutes of health stroke scale,NIHSS)评分。结果:训练前,三组下肢FMA、BBS、FAC评分、6MWT、MBI、NIHSS评分比较,差异均无统计学意义(P>0.05);训练后,C组下肢FMA、BBS、FAC、MBI评分均明显更高于A组、B组,6MWT长于A组、B组,NIHSS评分低于A组、B组,差异均有统计学意义(P<0.05);A组、B组各项指标比较,差异均无统计学意义(P>0.05)。结论:在脑卒中后对患者采取下肢康复机器人联合悬吊运动训练,可提高患者下肢运动功能与步行能力,增强患者平衡与下肢运动功能,并改善神经功能,提高生活质量,促进身体康复。
基金financial support from National Natural Science Foundation of China(Grant No.61601491)Natural Science Foundation of Hubei Province,China(Grant No.2018CFC865)Military Research Project of China(-Grant No.YJ2020B117)。
文摘To solve the problem of multi-target hunting by an unmanned surface vehicle(USV)fleet,a hunting algorithm based on multi-agent reinforcement learning is proposed.Firstly,the hunting environment and kinematic model without boundary constraints are built,and the criteria for successful target capture are given.Then,the cooperative hunting problem of a USV fleet is modeled as a decentralized partially observable Markov decision process(Dec-POMDP),and a distributed partially observable multitarget hunting Proximal Policy Optimization(DPOMH-PPO)algorithm applicable to USVs is proposed.In addition,an observation model,a reward function and the action space applicable to multi-target hunting tasks are designed.To deal with the dynamic change of observational feature dimension input by partially observable systems,a feature embedding block is proposed.By combining the two feature compression methods of column-wise max pooling(CMP)and column-wise average-pooling(CAP),observational feature encoding is established.Finally,the centralized training and decentralized execution framework is adopted to complete the training of hunting strategy.Each USV in the fleet shares the same policy and perform actions independently.Simulation experiments have verified the effectiveness of the DPOMH-PPO algorithm in the test scenarios with different numbers of USVs.Moreover,the advantages of the proposed model are comprehensively analyzed from the aspects of algorithm performance,migration effect in task scenarios and self-organization capability after being damaged,the potential deployment and application of DPOMH-PPO in the real environment is verified.
基金supported by the National Natural Science Foundation of China(22108188,U21A20303,U20A20141)CAS Project for Young Scientists in Basic Research(YSBR-039)。
文摘A nickel hexacyanoferrate(NiHCF)film electrode was prepared with NiHCF,conductive carbon black,and polyvinylidene difluoride,which was coated on graphite plate substrate for selective extraction of Cs^(+)ions by using electrochemically switched ion exchange(ESIX)technology.A potential-responsive ionpump system for efficient extraction of Cs+ions was designed,and the effect of wet film thicknesses,charging modes,flow rates,and chamber widths on Cs+ions extraction performance was investigated.In the system,the adsorption capacity and removal percentage of Cs^(+)ions on the NiHCF film electrode reached as high as 147.69 mg·g^(-1)and 92.47%,respectively.Furthermore,the NiHCF film electrode showed high selectivity for Cs^(+)ions and stability.After seven cycles of adsorption/desorption,the desorption percentage could reach about 100%.The excellent Cs^(+)extraction performance should be attributed to the strong driving force produced by the potential-responsive ion-pumping effect in the ESIX process,as well as the low ion transfer resistance of the film electrode which is caused by the special crystal structure of NiHCF.In addition,the NiHCF film electrode was implemented to work together with the bismuth oxybromide(BiOBr)film electrode to accomplish the simultaneous extraction of Cs^(+)and Br^(-).And the adsorption capacity and removal percentage of Br^(-)ions on the BiOBr film electrode reached 69.53 mg·g^(-1)and 77.32%,correspondingly.It is expected that such a potential-responsive ion-pump system based on NiHCF and BiOBr film electrodes could be used for the selective extraction and concentration of Cs^(+)and Br^(-)ions from salt lake brine.
基金Supported by the National Natural Science Foundation of China
文摘The New Vacuum Solar Telescope(NVST) is a one meter vacuum solar telescope that aims to observe fine structures on the Sun. The main goals of NVST are high resolution imaging and spectral observations, including measurements of the solar magnetic field. NVST is the primary ground-based facility used by the Chinese solar research community in this solar cycle. It is located by Fuxian Lake in southwest China, where the seeing is good enough to perform high resolution observations. We first introduce the general conditions at the Fuxian Solar Observatory and the primary science cases of NVST. Then, the basic structures of this telescope and instruments are described in detail. Finally, some typical high resolution data of the solar photosphere and chromosphere are also shown.
基金partially supported by the National Natural Science Foundation of China (Grant No. 11103075)the West Light Foundation of Chinese Academy of Sciences
文摘The Multi-wavelength Spectrometer is a medium-dispersion(R^130 000)grating spectrometer installed on the New Vacuum Solar Telescope at the Fuxian Solar Observatory,Yunnan Astronomical Observatory,Chinese Academy of Sciences.It is designed to accurately observe the velocity and magnetic fields of the Sun.The present configuration of this spectrometer allows us to simultaneously observe three different solar spectral lines.This work is dedicated to showing the first observations carried out in both the Hαand Ca II 8542 A lines.We give a detailed description of the data reduction process,focusing on the retrieval of a flat field from the high-resolution spectral data.Two different methods are also performed and compared to eliminate the residual fringe in the reduced data.The real spectral resolution and instrumental profile are analyzed based on the final results,which indicate that this spectrometer presently satisfies the expected performance and it is ready for further scientific observations.
基金supported by the Joint Research Fund in Astronomy (U1631127, U1631129 and U1831204) under cooperative agreement between the National Natural Science Foundation of China (NSFC) and Chinese Academy of Sciences (CAS)the National Natural Science Foundation of China (NSFC) (11473068, 11603072 and 11573067)+1 种基金the National Key R&D Program of China (2018YFA0404603)supported by the Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences (CAS)
文摘The Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China,has been available to the worldwide astronomical community since 2008. It is located at the Gaomeigu site,Lijiang Observatory(LJO), in the southwest of China. The site has very good observational conditions.During its 10-year operation, several instruments have been equipped on the LJT. Astronomers can perform both photometric and spectral observations. The main scientific goals of LJT include recording photometric and spectral evolution of supernovae, reverberation mapping of active galactic nuclei, investigating the physical properties of binary stars and near-earth objects(comets and asteroids), and identification of exoplanets and all kinds of transients. Until now, the masses of 41 high accretion rate black holes have been measured, and more than 168 supernovae have been identified by the LJT. More than 190 papers related to the LJT have been published. In this paper, the general observation conditions of the Gaomeigu site is introduced at first. Then, the structure of the LJT is described in detail, including the optical, mechanical, motion and control system. The specification of all the instruments and some detailed parameters of the YFOSC is also presented. Finally, some important scientific results and future expectations are summarized.
基金supported by the National Natural Science Foundation of China(61101205)the Natural Science Foundation of Hubei Province of China(2009CDB337)the Natural Science Foundation of Naval University of Engineering(HGDQNJJ13019)
文摘Aimed at the abominable influences to blind equalization algorithms caused by complex timespace variability existing in underwater acoustic channels, a new selfadjusting decision feedback equalization(DFE) algorithm adapting to different underwater acoustic channel environments is proposed by changing its central tap position. Besides, this new algorithm behaves faster convergence speed based on the analysis of equalizers' working rules, which is more suitable to implement communications in different unknown channels. Corresponding results and conclusions are validated by simulations and spot experiments.
基金supported by the National Natural Science Foundation of China(Grant Nos.11873091,11773040,11773072 and 11373044)。
文摘This paper is devoted to the primary spectro-polarimetric observation performed at the New Vacuum Solar Telescope(NVST)of China since 2017,and our aim is to precisely evaluate the real polarimetric accuracy and sensitivity of this polarimetry by using full Stokes spectro-polarimetric observations of the photospheric line Fe I 532.4 nm.In the work,we briefly describe the salient characteristic of the NVST as a polarimeter in terms of technology and then characterize its instrumental polarization based on the operation in 2017 and 2019.It is verified that the calibration method utilizing the instrumental polarization calibration unit(ICU)is stable and credible.The calibration accuracy can reach up to 3×10^-3.Based on the scientific observation of NOAA Active Region 12645 on 2017 April 5,we estimate that the residual cross-talk from Stokes I to Stokes Q,U and V,after the instrumental polarization calibration,is about 4×10^-3 on average,which is consistent with the calibration accuracy and close to the photon noise.The polarimetric sensitivity(i.e.,the detection limit)for polarized light is of the order of 10-3 with an integration time over 20 s.Slow modulation rate is indeed an issue for the present system.The present NVST polarimeter is expected to be integrated with a high-order adaptive optics system and a field scanner to realize 2 D vector magnetic field measurements in the following instrumentation update.
文摘Neurodegeneration and traumatic brain injuries are leading causes of disability and present an enormous disease burden both in terms of patient suffering and healthcare cost.Treatment of brain lesions remains as a major challenge in medicine largely because of the limited regenerative capacity of the adult brain.Neural
