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Magnetic stimulation at Neiguan(PC6) acupoint increases connections between cerebral cortex regions

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Neural Regeneration Research 2016年第7期11卷 1141-1146页

作者： Hong-li Yu Gui-zhi Xu Lei Guo Ling-di Fu Shuo Yang Shuo Shi Hua Lv province-Ministry Joint key laboratory of electromagnetic field and electrical apparatus reliability Hebei University of Technology

Stimulation at specific acupoints can activate cortical regions in human subjects.Previous studies have mainly focused on a single brain region.However,the brain is a network and many brain regions participate in the same task.The study of a single brain region alone cannot clearly explain any brain-related issues.Therefore,for the present study,magnetic stimulation was used to stimulate the Neiguan（PC6） acupoint,and 32-channel electroencephalography data were recorded before and after stimulation.Brain functional networks were constructed based on electroencephalography data to determine the relationship between magnetic stimulation at the PC6 acupoint and cortical excitability.Results indicated that magnetic stimulation at the PC6 acupoint increased connections between cerebral cortex regions.

关键词： stimulation acupoint cortex cortical participate frontal minutes alone handed acupuncture

Vertical sections of Tb_(0.15)Ho_(0.85)Fe_y-Tb_(0.3)Dy_(0.7)Fe_y(y=1.85, 1.9, 2.0) in Tb-Dy-Ho-Fe system

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Journal of Rare Earths 2015年第11期33卷 1170-1174页

作者：王博文黄文美翁玲孙英曹淑瑛王志华 province-Ministry Joint key laboratory of electromagnetic field and electrical apparatus reliability Hebei University of Technology

The x（Tb0.15Ho0.85Fey）＋（1–x）（Tb0.3Dy0.7Fey）（x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9; y=1.85, 1.9, 2.0） samples were prepared by a vacuum arc furnace, and annealed at 1000 oC for 1 d and at 950 oC for a week. Three vertical sections of Tb0.15Ho0.85Fey-Tb0.3Dy0.7Fey（y=1.85, 1.9, 2.0） in the Tb-Dy-Ho-Fe system were determined using optical microscopy, scanning electron microscopy, energy dispersion X-ray spectroscopy, X-ray diffraction, and differential thermal analysis. These vertical sections consisted of two single-phase regions： L and（Tb,Dy,Ho）Fe2; four two-phase regions： L＋（Tb,Dy,Ho）Fe3, L＋（Tb,Dy,Ho）Fe2,（Tb,Dy,Ho）Fe2＋（Tb,Dy,Ho）Fe3, and（Tb,Dy,Ho）Fe2＋（Tb,Dy,Ho）. The high Ho content of（Tb,Dy,Ho）Fey alloys led to the elevation of the peritectic temperature of L＋（Tb,Dy,Ho）Fe3→（Tb,Dy,Ho）Fe2. The region of（Tb,Dy,Ho）Fe2 phase was shifted towards the side of rich-Ho with the Fe content increasing. It meant that the substitution of Ho for Dy or Tb had a marked effect on the solidification process of（Tb,Dy,Ho）Fe2 compounds.

关键词： Tb-Dy-Ho-Fe system phase relationship vertical section microstructure rare earths

Numerical simulation of the initial plasma formation and current transfer in single-wire electrical explosion in vacuum

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Chinese Physics B 2017年第7期26卷 256-261页

作者：王坤史宗谦石元杰白骏吴坚贾申利邱爱慈 province–Ministry Joint key laboratory of electromagnetic field and electrical apparatus reliability Hebei University of Technology State key laboratory of electrical Insulation and Power Equipment Xi'an Jiaotong University

In this paper, a computational model is constructed to investigate the phenomenon of the initial plasma formation and current transfer in the single-wire electrical explosion in a vacuum. The process of the single-wire electrical explosion is divided into four stages. Stage Ⅰ： the wire is in solid state. Stage Ⅱ： the melting stage. Stage Ⅲ： the wire melts completely and the initial plasma forms. Stage IV： the core and corona expand separately. The thermodynamic calculation is applied before the wire melts completely in stages Ⅰ and Ⅱ. In stage Ⅲ, a one-dimensional magnetohydrodynamics model comes into play until the instant when the voltage collapse occurs. The temperature, density, and velocity, which are derived from the magnetohydrodynamics calculation, are averaged over the distribution area. The averaged parameters are taken as the initial conditions for stage Ⅳ in which a simplified magnetohydrodynamics model is applied. A wide-range semi-empirical equation of state, which is established based on the Thomas-Fermi-Kirzhnits model, is constructed to describe the phase transition from solid state to plasma state. The initial plasma formation and the phenomenon of current transfer in the electrical explosion of aluminum wire are investigated using the computational model. Experiments of electrical explosion of aluminum wires are carried out to verify this model. Simulation results are also compared with experimental results of the electrical explosion of copper wire.

关键词： single-wire electrical explosion plasma formation current transfer

Torque Ripple Reduction of Synchronous Reluctance Machine by Using Asymmetrical Barriers and Hybrid Magnetic Core

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CES Transactions on electrical Machines and Systems 2021年第1期5卷 13-20页

作者： Chengcheng Liu Kelin Wang Shaopeng Wang Youhua Wang Jianguo Zhu State key laboratory of reliability and Intelligence of electrical Equipment Hebei University of Technology and Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei ProvinceHebei University of TechnologyTianjin300130China school of electrical and information engineering University of SydneyNSW 2007Australia

As there is no need of permanent magnet(PM)material and only silicon steel sheet required on the rotor,synchronous reluctance machine(SynRM)can be used for many applications and draws a great research interest.For the SynRM,the torque ripple is a big issue and a great of work could been done on reducing it.In this paper,asymmetrical magnetic flux barriers in the SynRM rotor were studied comprehensively,including angle and width of each layer and each side of the magnetic barrier.The SynRMb with asymmetrical and parallel magnetic flux barrier was found as the best way to design SynRM based on the multi-objective design optimization method.Moreover,each parameter was studied to show the design rule of the asymmetrical magnetic flux barrier.As the average torque will be reduced with the asymmetrical barrier is used,the grain-oriented silicon steel is used on stator teeth of the SynRMb(SynRMbG)was proposed and studied.The analysis results show that the proposed new method can make the SynRM have better performance.

关键词： Torque ripple reduction synchronous reluctance machine asymmetrical barriers hybrid magnetic core

Optimization-based topology identification of complex networks

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Chinese Physics B 2011年第11期20卷 127-133页

作者：唐圣学陈丽何怡刚 province-Ministry Joint key laboratory of electromagnetic field and electrical apparatus reliability Hebei University of Technology College of electrical and Information Engineering Hunan University

In many cases, the topological structures of a complex network are unknown or uncertain, and it is of significance to identify the exact topological structure. An optimization-based method of identifying the topological structure of a complex network is proposed in this paper. Identification of the exact network topological structure is converted into a minimal optimization problem by using the estimated network. Then, an improved quantum-behaved particle swarm optimization algorithm is used to solve the optimization problem. Compared with the previous adaptive synchronization- based method, the proposed method is simple and effective and is particularly valid to identify the topological structure of synchronization complex networks. In some cases where the states of a complex network are only partially observable, the exact topological structure of a network can also be identified by using the proposed method. Finally, numerical simulations are provided to show the effectiveness of the proposed method.

关键词： complex networks topology identification optimization particle swarm

Survey of the electrical apparatus reliability Developments in China

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Survey of the Electrical Apparatus Reliability Developments ...

Analysis of the effect of repeated-pulse transcranial magnetic stimulation at the Guangming point on electroencephalograms

The 26th International Conference on electrical contacts and the 4th International Conference on reliability of electrical Products & electrical Contacts

作者： Lu Jianguo Wang Jingqin Luo Yanyan province-Ministry Joint key laboratory of electromagnetic field and electrical apparatus reliability Hebei University of Technology

The paper is a survey of the development history of the research on reliability of Chinese electrical apparatus.It describes the relationship between electrical apparatus reliability study and elec

ISBN: (纸本)9781622763139;1622763130

The paper is a survey of the development history of the research on reliability of Chinese electrical apparatus.It describes the relationship between electrical apparatus reliability study and elec

关键词： Electric apparatus Electric contacts

来源： cnki会议评论

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cnki会议

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Neural Regeneration Research 2014年第5期9卷 549-554页

作者： Xin Zhang Lingdi Fu Yuehua Geng Xiang Zhai Yanhua Liu Tianjin Polytechnic University province-Ministry Joint key laboratory of electromagnetic field and electrical apparatus reliability Hebei University of Technology Department of Otorhinolaryngology Tianjin Huanhu Hospital hebei College of Industry and Technology

Here, we administered repeated-pulse transcranial magnetic stimulation to healthy people at the left Guangming （GB37） and a mock point, and calculated the sample entropy of electroencephalo- gram signals using nonlinear dynamics. Additionally, we compared electroencephalogram sample entropy of signals in response to visual stimulation before, during, and after repeated-pulse tran- scranial magnetic stimulation at the Guangming. Results showed that electroencephalogram sample entropy at left （F3） and right （FP2） frontal electrodes were significantly different depending on where the magnetic stimulation was administered. Additionally, compared with the mock point, electroencephalogram sample entropy was higher after stimulating the Guangming point. When visual stimulation at Guangming was given before repeated-pulse transcranial magnetic stimula- tion, significant differences in sample entropy were found at five electrodes （C3, Cz, C4, P3, T8） in parietal cortex, the central gyrus, and the right temporal region compared with when it was given after repeated-pulse transcranial magnetic stimulation, indicating that repeated-pulse transcranial magnetic stimulation at Guangming can affect visual function. Analysis of electroencephalogram revealed that when visual stimulation preceded repeated pulse transcranial magnetic stimulation, sample entropy values were higher at the C3, C4, and P3 electrodes and lower at the Cz and T8 electrodes than visual stimulation followed preceded repeated pulse transcranial magnetic stimula- tion. The findings indicate that repeated-pulse transcranial magnetic stimulation at the Guangming evokes different patterns of electroencephalogram signals than repeated-pulse transcranial mag- netic stimulation at other nearby points on the body surface, and that repeated-pulse transcranial magnetic stimulation at the Guangrning is associated with changes in the complexity of visually evoked electroencephalogram signals in parietal regions, central gyrus, and temporal regions.

关键词： nerve regeneration brain injury acupuncture magnetic stimulation acupuncture poi- nt mock point Guangming point brain function electroencephalogram signals complexity sample entropy nonlinear dynamics NSFC grant neural regeneration

Coexistence behavior of asymmetric attractors in hyperbolic-type memristive Hopfield neural network and its application in image encryption

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Chinese Physics B 2024年第3期33卷 302-315页

作者：李晓霞何倩倩余天意才壮徐桂芝 Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province Hebei University of TechnologyTianjin 300130China State key laboratory of reliability and Intelligence of electrical Equipment Hebei University of TechnologyTianjin 300130China School of Life Science & Health Engineering Hebei University of TechnologyTianjin 300130China

The neuron model has been widely employed in neural-morphic computing systems and chaotic circuits.This study aims to develop a novel circuit simulation of a three-neuron Hopfield neural network(HNN)with coupled hyperbolic memristors through the modification of a single coupling connection weight.The bistable mode of the hyperbolic memristive HNN(mHNN),characterized by the coexistence of asymmetric chaos and periodic attractors,is effectively demonstrated through the utilization of conventional nonlinear analysis techniques.These techniques include bifurcation diagrams,two-parameter maximum Lyapunov exponent plots,local attractor basins,and phase trajectory diagrams.Moreover,an encryption technique for color images is devised by leveraging the mHNN model and asymmetric structural attractors.This method demonstrates significant benefits in correlation,information entropy,and resistance to differential attacks,providing strong evidence for its effectiveness in encryption.Additionally,an improved modular circuit design method is employed to create the analog equivalent circuit of the memristive HNN.The correctness of the circuit design is confirmed through Multisim simulations,which align with numerical simulations conducted in Matlab.

关键词： hyperbolic-type memristor Hopfield neural network(HNN) asymmetric attractors image encryption

Effect of sintering temperature on the physical properties and electrical contact properties of doped AgSnO_2 contact materials

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1275-1285页

作者： Hai-tao Wang Zi-xiang Wang Lian-zheng Wang Jing-qin Wang Yan-cai Zhu State key laboratory of reliability and Intelligence of electrical Equipment School of Electrical EngineeringHebei University of Technology Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province School of Electrical EngineeringHebei University of Technology

AgSnO_ 2 electrical contact materials doped with Bi_2O_3,La_2O_3,and TiO_2 were successfully fabricated by the powder metallurgy method under different initial sintering temperatures.The electrical conductivity,density,hardness,and contact resistance of the Ag Sn O_2/Bi_2O_3,AgSnO_2/La_2O_3,and AgSnO_2/Ti O_2 contact materials were measured and analyzed.The arc-eroded surface morphologies of the doped AgSnO_2 contact materials were investigated by scanning electron microscopy(SEM).The effects of the initial sintering temperature on the physical properties and electrical contact properties of the doped AgSnO_2 contact materials were discussed.The results indicate that the physical properties can be improved and the contact resistance of the AgSnO_2 contact materials can be substantially reduced when the materials are sintered under their optimal initial sintering temperatures.

关键词： sintering temperature contact materials physical properties electrical contact properties