The mismatch effect induced by the radial motion of a target is analyzed for linear frequency modulated （LFM） signals. Then, a novel integrated processing scheme is proposed to re- solve the delay-Doppler coupling e...The mismatch effect induced by the radial motion of a target is analyzed for linear frequency modulated （LFM） signals. Then, a novel integrated processing scheme is proposed to re- solve the delay-Doppler coupling effect in LFM pulse compression. Therefore the range and radial velocity of the target can be si- multaneously estimated with a narrowband LFM pulse. Finally, numerical simulation results demonstrate the effectiveness and good performance of the proposed method.展开更多
The two-color circularly polarized pulses scheme was proposed to generate isolated attosecond pulses in our previous work [Phys. Rev. A 87 （2013） 043406], while the polarization of the attosecond pulse was not inves...The two-color circularly polarized pulses scheme was proposed to generate isolated attosecond pulses in our previous work [Phys. Rev. A 87 （2013） 043406], while the polarization of the attosecond pulse was not investigated. We show a supplementary explanation of this scheme and present another scheme to generate linear isolated attosecond pulses by combining a circularly polarized pulse with an elliptically polarized pulse. High-order harmonic generation and quantum path control are investigated to compare these two schemes. Both schemes can obtain supercontinuum spectra plateau from about 200eV to 550eV, which belong to the water window region. It is found that the latter scheme can clearly eliminate the short quantum path and extend the harmonic plateau. A linear isolated attosecond pulse with a duration of sub-6Oas can be generated by superposing a bandwidth of 70eV.展开更多
In this paper,we give a review of some most powerful pulsed systems developed at the Institute of High Current Electronics(HCEI),Siberian Branch,Russian Academy of Sciences,and describe latest achievements of the team...In this paper,we give a review of some most powerful pulsed systems developed at the Institute of High Current Electronics(HCEI),Siberian Branch,Russian Academy of Sciences,and describe latest achievements of the teams dealing with these installations.Besides the presented high-power systems,HCEI performs numerous investigations using much less powerful generators.For instance,last year much attention was paying to the research and development of the intense low-energy(<200 kV)high-current electron and ion beam and plasma sources,and their application in the technology[1-3].展开更多
Objective:Based on the theories of“defensive Qi entering Yin”and“Qi and blood in meridians”in traditional Chinese medicine(TCM),this study explores the synergistic intervention effect of the Brain Health Sleep-Aid...Objective:Based on the theories of“defensive Qi entering Yin”and“Qi and blood in meridians”in traditional Chinese medicine(TCM),this study explores the synergistic intervention effect of the Brain Health Sleep-Aid Pillow on brain diseases(such as insomnia,vertigo)and cervical spondylosis.The pillow achieves“marrow sea replenishment and unobstructed cerebral collaterals”by regulating cerebral blood perfusion and cervical mechanical balance through linear pulsed magnetic guidance of the Du Meridian and Bladder Meridian.Methods:A total of 120 patients with“neck impediment”and“insomnia”who met the Criteria for Diagnosis and Therapeutic Effect of TCM Syndromes were enrolled.They were randomly divided into an experimental group(60 cases,using Yuxuangong magnetic therapy pillow)and a control group(60 cases,using ordinary buckwheat pillow)by block randomization.The intervention lasted for 8 weeks.The efficacy was comprehensively evaluated using indicators including TCM syndrome scores,tongue and pulse analysis,cervical range of motion assessment,sleep quality(PSQI scale),and transcranial Doppler(TCD)[1].Results:The total TCM syndrome score in the experimental group decreased significantly more than that in the control group(-4.5±1.2 vs.-2.3±0.8,P<0.001);The cervical flexion range of motion increased by 15.3°±3.2°(P<0.01),and the total PSQI score decreased by 6.5 points(P<0.001);In the experimental group,the vertebral artery blood flow velocity increased by 12.3%(P<0.05),and the serum IL-6 level decreased by 0.08 pg/mL(P<0.05)[2].Conclusion:The Yuxuangong Brain Health Sleep-Aid Pillow provides a modern scientific interpretation of the TCM theory of“defensive Qi entering Yin”through a three-dimensional mechanism of“magnetic field regulating Qi and dredging collaterals,and physical mechanical reset”,which has significant clinical transformation value[3].展开更多
The robust control law for gas tungsten arc welding dynamic process, which is a typical sampled-data system and full of uncertainties, is presented. By using the Lyapunov, second method, the robust control and robust ...The robust control law for gas tungsten arc welding dynamic process, which is a typical sampled-data system and full of uncertainties, is presented. By using the Lyapunov, second method, the robust control and robust optimal control for a class of sampled-data systems whose underlying continuous-time systems are subjected to structured uncertainties are discussed in time-domain. As a result, some sufficient conditions of robust stability and the corresponding robust control laws are derived. All these results are designed by solving a class of linear matrix inequalities （LMIs） and a class of dynamic optimization problem with LMIs constraints respectively. An example adapted under some experimental conditions in the dynamic process of gas tungsten arc welding system in which the controlled variable is the backside width of weld pool and controlling variable pulse duty ratio, is worked out to illustrate the proposed results, it is shown that the sampling period is the crucial design oarameter.展开更多
The effect of a metal shell on the launch efficiency of an asynchronous coil launcher(coil AC pulse linear motor)remains insufficiently understood in terms of the underlying mechanisms and principles.To address this g...The effect of a metal shell on the launch efficiency of an asynchronous coil launcher(coil AC pulse linear motor)remains insufficiently understood in terms of the underlying mechanisms and principles.To address this gap,this study conducted extensive modelling simulations and calculations,varying the shell's conductivity,permeability,and dimensions.Through comparative analysis of these models,this paper identifies a unique‘tick-shaped efficiency curve’for the asynchronous coil launcher:the launch efficiency first decreases and then increases as the shell's electromagnetic parameters are enhanced.Enhancements that bolster the electromagnetic induction effect within the shell-such as increased conductivity,permeability and dimensions-are termed as the augmentation of electromagnetic parameters.This study delves into Lenz's law of electromagnetism to elucidate the observed phenomena,attributing them to the spatio-temporal force characteristics of the multipeak and multi-valley armature of the transmitting device,and the resulting‘tick-shaped efficiency curve’.A comprehensive summary of shell-related research in electromagnetic emission reveals that the driving current fundamentally dictates the shell's impact on launch efficiency.DC-driven launchers conform to the monotonic effect efficiency curve,whereas AC-driven launchers conform to the tick-shaped efficiency curve.展开更多
基金supported by the Pre-Research Foundation of National Defence of China
文摘The mismatch effect induced by the radial motion of a target is analyzed for linear frequency modulated （LFM） signals. Then, a novel integrated processing scheme is proposed to re- solve the delay-Doppler coupling effect in LFM pulse compression. Therefore the range and radial velocity of the target can be si- multaneously estimated with a narrowband LFM pulse. Finally, numerical simulation results demonstrate the effectiveness and good performance of the proposed method.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11404204 and 11447208the Key Project of Chinese Ministry of Education under Grant No 211025+1 种基金the Research Fund for the Doctoral Program of Higher Education of China under Grant No 20111404120004the Natural Science Foundation for Young Scientists of Shanxi Province under Grant No 2009021005
文摘The two-color circularly polarized pulses scheme was proposed to generate isolated attosecond pulses in our previous work [Phys. Rev. A 87 （2013） 043406], while the polarization of the attosecond pulse was not investigated. We show a supplementary explanation of this scheme and present another scheme to generate linear isolated attosecond pulses by combining a circularly polarized pulse with an elliptically polarized pulse. High-order harmonic generation and quantum path control are investigated to compare these two schemes. Both schemes can obtain supercontinuum spectra plateau from about 200eV to 550eV, which belong to the water window region. It is found that the latter scheme can clearly eliminate the short quantum path and extend the harmonic plateau. A linear isolated attosecond pulse with a duration of sub-6Oas can be generated by superposing a bandwidth of 70eV.
基金supported in part by Russian Foundation for Basic Research(project No.15-08-01324).
文摘In this paper,we give a review of some most powerful pulsed systems developed at the Institute of High Current Electronics(HCEI),Siberian Branch,Russian Academy of Sciences,and describe latest achievements of the teams dealing with these installations.Besides the presented high-power systems,HCEI performs numerous investigations using much less powerful generators.For instance,last year much attention was paying to the research and development of the intense low-energy(<200 kV)high-current electron and ion beam and plasma sources,and their application in the technology[1-3].
文摘Objective:Based on the theories of“defensive Qi entering Yin”and“Qi and blood in meridians”in traditional Chinese medicine(TCM),this study explores the synergistic intervention effect of the Brain Health Sleep-Aid Pillow on brain diseases(such as insomnia,vertigo)and cervical spondylosis.The pillow achieves“marrow sea replenishment and unobstructed cerebral collaterals”by regulating cerebral blood perfusion and cervical mechanical balance through linear pulsed magnetic guidance of the Du Meridian and Bladder Meridian.Methods:A total of 120 patients with“neck impediment”and“insomnia”who met the Criteria for Diagnosis and Therapeutic Effect of TCM Syndromes were enrolled.They were randomly divided into an experimental group(60 cases,using Yuxuangong magnetic therapy pillow)and a control group(60 cases,using ordinary buckwheat pillow)by block randomization.The intervention lasted for 8 weeks.The efficacy was comprehensively evaluated using indicators including TCM syndrome scores,tongue and pulse analysis,cervical range of motion assessment,sleep quality(PSQI scale),and transcranial Doppler(TCD)[1].Results:The total TCM syndrome score in the experimental group decreased significantly more than that in the control group(-4.5±1.2 vs.-2.3±0.8,P<0.001);The cervical flexion range of motion increased by 15.3°±3.2°(P<0.01),and the total PSQI score decreased by 6.5 points(P<0.001);In the experimental group,the vertebral artery blood flow velocity increased by 12.3%(P<0.05),and the serum IL-6 level decreased by 0.08 pg/mL(P<0.05)[2].Conclusion:The Yuxuangong Brain Health Sleep-Aid Pillow provides a modern scientific interpretation of the TCM theory of“defensive Qi entering Yin”through a three-dimensional mechanism of“magnetic field regulating Qi and dredging collaterals,and physical mechanical reset”,which has significant clinical transformation value[3].
基金This project is supported by Doctor's Research Fund of Science Education Ministry of China(No.20060214004)Scientific Research Fund Education Ministry of China(No.206041)Scientific Research Fund of Harbin Sci-ence Bureau China(No.20051AAICG037).
文摘The robust control law for gas tungsten arc welding dynamic process, which is a typical sampled-data system and full of uncertainties, is presented. By using the Lyapunov, second method, the robust control and robust optimal control for a class of sampled-data systems whose underlying continuous-time systems are subjected to structured uncertainties are discussed in time-domain. As a result, some sufficient conditions of robust stability and the corresponding robust control laws are derived. All these results are designed by solving a class of linear matrix inequalities （LMIs） and a class of dynamic optimization problem with LMIs constraints respectively. An example adapted under some experimental conditions in the dynamic process of gas tungsten arc welding system in which the controlled variable is the backside width of weld pool and controlling variable pulse duty ratio, is worked out to illustrate the proposed results, it is shown that the sampling period is the crucial design oarameter.
基金supported by Scientific Instrument Developing Project of Chinese Academy of Sciences(Grant/Award YJKYYQ20200011)Chinese Academy of Sciences‘Light of West China’Program(Grant/Award xbzg-zdsys-202317).
文摘The effect of a metal shell on the launch efficiency of an asynchronous coil launcher(coil AC pulse linear motor)remains insufficiently understood in terms of the underlying mechanisms and principles.To address this gap,this study conducted extensive modelling simulations and calculations,varying the shell's conductivity,permeability,and dimensions.Through comparative analysis of these models,this paper identifies a unique‘tick-shaped efficiency curve’for the asynchronous coil launcher:the launch efficiency first decreases and then increases as the shell's electromagnetic parameters are enhanced.Enhancements that bolster the electromagnetic induction effect within the shell-such as increased conductivity,permeability and dimensions-are termed as the augmentation of electromagnetic parameters.This study delves into Lenz's law of electromagnetism to elucidate the observed phenomena,attributing them to the spatio-temporal force characteristics of the multipeak and multi-valley armature of the transmitting device,and the resulting‘tick-shaped efficiency curve’.A comprehensive summary of shell-related research in electromagnetic emission reveals that the driving current fundamentally dictates the shell's impact on launch efficiency.DC-driven launchers conform to the monotonic effect efficiency curve,whereas AC-driven launchers conform to the tick-shaped efficiency curve.
