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Plasma Science and technology 2024年第5期26卷 47-55页

作者：李宜霖廖晖周海洋孙玄 Department of Plasma Physics and fusion Engineering School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026People’s Republic of China

Field reversed configuration(FRC)is widely considered as an ideal target plasma for magnetoinertial ***,its confinement and stability,both proportional to the radius,will deteriorate inevitably during radial ***,we propose a new fusion approach based on axial compression of a large-sized *** axial compression can be made by plasma jets or plasmoids converging onto the axial ends of the *** parameter space that can reach the ignition condition while preserving the FRC's overall quality is studied using a numerical model based on different FRC confinement *** is found that ignition is possible for a large FRC that can be achieved with the current FRC formation techniques if compression ratio is greater than 50.A more realistic compression is to combine axial with moderate radial compression,which is also presented and calculated in this work.

关键词： field reversed configuration magnetized target fusion axial compression

Behaviors analysis of on-coming cluster based on knowledge under cluster security requirements

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Chinese Journal of Aeronautics 2024年第9期37卷 448-462页

作者： Huixia ZHANG Yan LIANG Ying SHI Yuedong WANG Chaoxiong MA Ran WANG school of Automation Northwestern Polytechnical UniversityXi'an 710129China Key Laboratory of Information fusion technology Ministry of EducationXi'an 710129China

Analysis of cluster behaviors of the on-coming cluster is an essential measure for high value locations on the *** target tracking and clustering analysis,cluster behaviors analysis under cluster security requirements remains an open issue,which is a joint analysis of clus-tering,intent reasoning and activity *** address this issue,a framework for cluster behav-iors analysis is proposed by incorporating expert knowledge and domain knowledge,and a knowledge-assisted score function with is designed to improve the accuracy of intent reasoning net-work,overcoming the effects of possible knowledge *** framework consists of three mod-ules for cluster analysis,intent reasoning and activity region analysis for typical tasks,in which an intent reasoning network is constructed to obtain cluster intents by using a hybrid knowledge and data driven ***,considering the complexity of the battlefield environment,dif-ferent tasks and corresponding activity region optimization functions are designed for cluster activ-ity region analysis,which are vital elements of cluster behaviors *** demonstrate the effectiveness of the proposed cluster behaviors analysis framework.

关键词： Cluster analysis Intent reasoning,Activity region analysis Cluster behavior Battlefield environment

Configuration and Kinematics of a 3-DOF Generalized Spherical Parallel Mechanism for Ankle Rehabilitation

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 176-188页

作者： Jianjun Zhang Shuai Yang Chenglei Liu Xiaohui Wang Shijie Guo school of Mechanical Engineering Hebei University of TechnologyTianjin 300401China Key Laboratory of Robot Perception and Human-Machine fusion Tianjin 300401China

The kinematic equivalent model of an existing ankle-rehabilitation robot is inconsistent with the anatomical structure of the human ankle,which influences the rehabilitation ***,this study equates the human ankle to the UR model and proposes a novel three degrees of freedom(3-DOF)generalized spherical parallel mechanism for ankle *** parallel mechanism has two spherical centers corresponding to the rotation centers of tibiotalar and subtalar *** screw theory,the mobility of the parallel mechanism,which meets the requirements of the human ankle,is *** inverse kinematics are presented,and singularities are identified based on the Jacobian *** workspaces of the parallel mechanism are obtained through the search method and compared with the motion range of the human ankle,which shows that the parallel mechanism can meet the motion demand of ankle ***,based on the motion-force transmissibility,the performance atlases are plotted in the parameter optimal design space,and the optimum parameter is obtained according to the demands of practical *** results show that the parallel mechanism can meet the motion requirements of ankle rehabilitation and has excellent kinematic performance in its rehabilitation range,which provides a theoretical basis for the prototype design and experimental verification.

关键词： Ankle rehabilitation Parallel mechanism Kinematic analysis Parameter optimization

Multi-Sensor fusion Adaptive Estimation for Nonlinear Under-observed System with Multiplicative Noise

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Chinese Journal of Electronics 2024年第1期33卷 282-292页

作者： Yongpeng CUI Xiaojun SUN school of Electronic Engineering Heilongjiang University Key Laboratory of Information fusion Estimation and Detection

The adaptive fusion estimation problem was studied for the multi-sensor nonlinear under-observed systems with multiplicative noise. A one-step predictor with state update equations was designed for the virtual state with virtual noise first of all. An extended incremental Kalman filter(EIKF) was then proposed for the nonlinear under-observed systems. Furthermore, an adaptive filtering method was given for optimization. The fusion adaptive incremental Kalman filter weighted by scalar was finally proposed. The comparison analysis was made to verify the optimization of the state estimation using adaptive filtering method in the filtering process.

关键词： Adaptive systems Information filters Matrices Adaptive estimation Kalman filters State estimation Nonlinear systems

Error field penetration in J-TEXT tokamak based on two-fluid drift-MHD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the J-TEXT team State Key Laboratory of Advanced Electromagnetic technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

Development of a toroidal soft x-ray imaging system and application for investigating three-dimensional plasma on J-TEXT

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Plasma Science and technology 2024年第3期26卷 94-99页

作者：赵传旭李建超张晓卿王能超丁永华杨州军江中和严伟李杨波毛飞越任正康 the J-TEXT Team International Joint Research Laboratory of Magnetic Confinement fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic Engineering and School of PhysicsHuazhong University of Science and TechnologyWuhan 430074People's Republic of China Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of TechnologyWuhan 430205People's Republic of China International Joint Research Laboratory of Magnetic Confinement fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China

A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on *** T-SXRI system consists of three sets of SXR *** sets are newly developed and located on the vacuum chamber wall at toroidal positionsφof 126.4°and 272.6°,respectively,while one set was established previously atφ=*** set of SXR arrays consists of three arrays viewing the plasma poloidally,and hence can be used separately to obtain SXR images via the tomographic *** sawtooth precursor oscillations are measured by T-SXRI,and the corresponding images of perturbative SXR signals are successfully reconstructed at these three toroidal positions,hence providing measurement of the 3D structure of precursor *** observed 3D structure is consistent with the helical structure of the m/n=1/1 *** experimental observation confirms that the T-SXRI system is able to observe 3D structures in the J-TEXT plasma.

关键词： SXR imaging J-TEXT tokamak three-dimensional measurement MHD

A synthetic diagnostics platform for microwave imaging diagnostics in tokamaks

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Plasma Science and technology 2024年第3期26卷 38-45页

作者：李子涵杨尚川徐新航张立夫渠承明李诚普庄革谢锦林 Department of Plasma Physics and fusion Engineering University of Science and Technology of ChinaHefei 230026People's Republic of China

Interpreting experimental diagnostics data in tokamaks,while considering non-ideal effects,is challenging due to the complexity of *** address this challenge,a general synthetic diagnostics(GSD)platform has been established that facilitates microwave imaging reflectometry and electron cyclotron emission *** platform utilizes plasma profiles as input and incorporates the finite-difference time domain,ray tracing and the radiative transfer equation to calculate the propagation of plasma spontaneous radiation and the external electromagnetic field in *** tests for classical cases have been conducted to verify the accuracy of every core module in the GSD ***,2D imaging of a typical electron temperature distribution is reproduced by this platform and the results are consistent with the given real experimental *** platform also has the potential to be extended to 3D electromagnetic field simulations and other microwave diagnostics such as cross-polarization scattering.

关键词： synthetic diagnostics tokamak plasmas microwave imaging diagnostics microwave imaging reflectometer electron cyclotron emission imaging

An improved TDE technique for derivation of 2D turbulence structures based on GPI data in toroidal plasma

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Plasma Science and technology 2024年第3期26卷 131-137页

作者：王威策程钧石中兵严龙文黄治辉弋开阳吴娜何钰邹千陈熙张文陈建聂林季小全钟武律 Southwestern Institute of Physics Chengdu 610299People's Republic of China Institute of fusion Science School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031People's Republic of China

This paper reports an improved time-delay estimation(TDE)technique for the derivation of turbulence structures based on gas-puff imaging *** improved TDE technique,integrating an inverse timing search and hierarchical strategy,offers superior accuracy in calculating turbulent velocity field maps and analyzing blob dynamics,which has the power to obtain the radial profiles of equilibrium poloidal velocity,blob size and its radial velocity,even the fluctuation analysis,such as geodesic acoustic modes and quasi-coherent mode,*** improved technique could provide important 2D information for the study of edge turbulence and blob dynamics,advancing the understanding of edge turbulence physics in fusion plasmas.

关键词： gas-puff imaging TDE method turbulence velocity field map

3D electromagnetic modelling for high-temperature superconducting dynamo flux pumps using T-A formulation

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High Voltage 2024年第2期9卷 367-379页

作者： Luning Hao Fangliang Dong Jintao Hu Qi Wang Haigening Wei Ismail Patel Adil Shah Yuyang Wu Tim Coombs Department of Engineering University of CambridgeCambridgeUK Plasma Science and fusion Center Massachusetts Institute of TechnologyCambridgeMassachusettsUSA

A high-temperature superconducting(HTS)dynamo flux pump can inject DC currents into closed-loop HTS magnets without *** enables the realisation of current-lead-free or even through-wall charging systems for high-field applications such as nuclear magnetic resonance/magnetic resonance imaging(MRI)magnets,fusion reactors and *** have proposed many simulation models to understand the working principle of HTS dynamos,few of which are in 3D because of converging ***,the influences of many key 3D parameters in the HTS dynamo are scarcely *** authors propose an efficient 3D modelling method of the HTS dynamo based on the T-A *** rotating magnets are modelled by a ring-shaped permanent magnet with space-time-variant remanent flux density to avoid moving ***,together with the T-A formulation,makes the 3D model efficient and *** accuracy of the model is verified by the experimental instantaneous and time-integrated dynamic *** this model,the authors present systematic case studies to thoroughly explore the influences of the key parameters of a dynamo flux pump on the dynamic voltage and *** proposed modelling method and results could significantly benefit the design and optimisation of HTS dynamos for high-field magnets.

关键词： formulation magnets pump

Structure-preserving algorithms for guiding center dynamics based on the slow manifold of classical Pauli particle

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Plasma Science and technology 2024年第6期26卷 88-102页

作者：张若涵王正汹肖建元王丰 Key Laboratory of Materials Modification by Laser Ion and Electron BeamsSchool of PhysicsDalian University of TechnologyDalian 116024People’s Republic of China Department of Plasma Physics and fusion Engineering University of Science and Technology of ChinaHefei 230026People’s Republic of China

The classical Pauli particle(CPP) serves as a slow manifold, substituting the conventional guiding center dynamics. Based on the CPP, we utilize the averaged vector field(AVF) method in the computations of drift orbits. Demonstrating significantly higher efficiency, this advanced method is capable of accomplishing the simulation in less than one-third of the time of directly computing the guiding center motion. In contrast to the CPP-based Boris algorithm, this approach inherits the advantages of the AVF method, yielding stable trajectories even achieved with a tenfold time step and reducing the energy error by two orders of magnitude. By comparing these two CPP algorithms with the traditional RK4 method, the numerical results indicate a remarkable performance in terms of both the computational efficiency and error elimination. Moreover, we verify the properties of slow manifold integrators and successfully observe the bounce on both sides of the limiting slow manifold with deliberately chosen perturbed initial conditions. To evaluate the practical value of the methods, we conduct simulations in non-axisymmetric perturbation magnetic fields as part of the experiments,demonstrating that our CPP-based AVF method can handle simulations under complex magnetic field configurations with high accuracy, which the CPP-based Boris algorithm lacks. Through numerical experiments, we demonstrate that the CPP can replace guiding center dynamics in using energy-preserving algorithms for computations, providing a new, efficient, as well as stable approach for applying structure-preserving algorithms in plasma simulations.

关键词： structure-preserving algorithm averaged vector field classical Pauli particle guiding center dynamics