EHL-2 spherical torus(ST)is one of the key steps of p-^(11)B(proton-boron or hydrogen-boron)fusion energy research in ENN.The fusion produced energy is carried mainly by alpha particles of average energy 3 MeV,which ideally can be converted to electricity with high efficiency(>80%).However,there exist serious difficulties to realize such conversion in a fusion device,due to the high energy density and high voltage required.To comprehensively describe the progress of the EHL-2 physics design,this work presents preliminary considerations of approaches for achieving energy conversion,highlighting critical issues for further investigation.Specifically,we provide an initial simulation of alpha particle extraction in the EHL-2 ST configuration as a starting point for p-^(11)B fusion energy conversion.
Huasheng XIEXiang GUYumin WANGQuanyun WANGFeng WANGHaozhe KONGJiaqi DONGYunfeng LIANGYueng-Kay Martin PENGMinsheng LIUthe EHL-2 Team
This paper presents the first comprehensive simulation study of p-11B fusion reactions in a spherical torus.We developed relevant program modules for fusion reactions based on energetic particle simulation frameworks and analyzed the two main fusion channels:thermal and beam-thermal.Using EHL-2 design parameters with n_(boron)=007n_(ion)and a hydrogen beam at 200 keV and 1 MW,our simulation indicates that p-11B reactions produce approximately 1.5×10^(15)αparticles per second(~0.7 kW)from the thermal channel,and5.3×10^(14)(~0.25 kW)from the beam-thermal channel.We conducted parameter scans to establish a solid physics foundation for the high ion temperature conditions(T_(i)>26ke V)designed for EHL-2.This work also laid the groundwork for studying various operation modes to explore different reaction channels.The simulation results suggest that the conditions in EHL-2 could be sufficient for investigating p-11B thermonuclear reactions.In addition,we found that EHL-2 offered good confinement for energetic particles,allowing us to research the interactions between these ions and plasmas.This research enhances our understanding of burning plasma physics.
Significant progress has been made in magnetic and inertial confinement fusion(MCF and ICF)energy development since the achievement of world record parameters on the T3 tokamak in 1968.In MCF,the triple product nτT has been elevated from 5×10^(17)m^(-3)·s·keV to 1×10^(21)m^(-3)·s·keV.At the same time,Q=Pfusion/Pheating,has increased from 1×10^(-9)to 0.67,with expectations to exceed 10 in the ITER experiment.In ICF,a Q value of approximately 2.4 was attained with a fusion energy output of around 5.2 MJ.
基于脑电信号(Electroencephalogram,EEG)和周围生理信号解码人类内部情绪状态是情感计算领域的关键,但使用脑电信号或周围生理信号模态的机器学习模型性能可能受到限制。文中基于单模态方法提出了一种多模态融合策略,对每个脑电信号片段提取了微分熵特征、统计特征和复杂度特征,并对这些特征与周围生理信号特征进行了适当整合。文中方法融合了DEAP(Database for Emotion Analysis using Physiological Signals)数据集中记录的多个模态特征。在效价方面,单一脑电特征的实验精度为49.21%,两类特征融合分别取得了56.39%、55.24%和56.98%的分类精度,3类模态融合的实验精度为56.98%。在唤醒方面,单一脑电特征的实验精度为49.34%,两类特征融合分别取得了54.53%、54.53%和59.39%的分类精度,3类特征融合的实验精度为55.48%。实验结果表明,脑电信号特征和外周围生理信号特征融合后的多模态特征分类精度最高,相比于单一的脑电信号特征分类精度分别提升了7.77%和10.05%。
