Article
Physics, Multidisciplinary
Nathan Shettell, William J. Munro, Damian Markham, Kae Nemoto
Summary: Noise is the greatest obstacle in quantum metrology that limits achievable precision and sensitivity. Quantum error correction can be beneficial, but with current technological limitations, achieving the Heisenberg limit remains challenging. Improvements in factors such as repetition frequency are needed to reliably reach the desired precision level.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
Edward H. Chen, Theodore J. Yoder, Youngseok Kim, Neereja Sundaresan, Srikanth Srinivasan, Muyuan Li, Antonio D. Corcoles, Andrew W. Cross, Maika Takita
Summary: Arbitrarily long quantum computations require quantum memories that can be repeatedly measured without being corrupted. In this study, the researchers were able to preserve the state of a quantum memory by using flagged error events. Fast, midcircuit measurements and resets of the physical qubits were used to extract all error events. A perfect matching decoder was introduced for comparison with other error decoders, and it was calibrated using measurements containing up to size-four correlated events. The researchers observed logical errors per round that surpass the physical measurement error, demonstrating the potential for repeated logical measurements.
PHYSICAL REVIEW LETTERS
(2022)
Article
Nuclear Science & Technology
L. Piron, M. Baruzzo, L. Baylor, C. D. Challis, M. P. Gryaznevich, T. C. Hender, R. B. Henriques, N. Hawkes, S. Jachmich, E. Joffrin, M. Lehnen, M. Lennholm, Y. Q. Liu, J. Mailloux, L. Moreira, D. Valcarcel
Summary: This paper describes the usage of Error Field Correction Coil (EFCC) system in introducing magnetic field perturbations, probing plasma stability, studying radiation asymmetry, and controlling edge localized modes in various plasma experiments.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Multidisciplinary Sciences
Jeremy A. Owen, Jordan M. Horowitz
Summary: Living organisms benefit from molecular sensitivity in key processes like DNA replication and chemical sensing. A simple structural quantity, the size of perturbation support, limits the sensitivity of biological processes, whether at or away from thermodynamic equilibrium. A novel non-equilibrium binding mechanism, nested hysteresis, with exponential sensitivity relative to the number of binding sites, has been discovered.
NATURE COMMUNICATIONS
(2023)
Article
Green & Sustainable Science & Technology
Shengming Tang, Tiantian Li, Yun Guo, Rong Zhu, Hongya Qu
Summary: This study conducted experimental tests on DWL at two national meteorological observatories in China and proposed a correction methodology based on multiple linear regression model to eliminate measurement errors induced by environmental conditions. The corrected DWL data showed significant improvements in accuracy and reliability.
Article
Engineering, Multidisciplinary
Hanwen Jia, Guanwen Cheng, Jiaxiang Li, Honglei Liu, Jiawei Qian
Summary: In a hydrostatic leveling system, errors can arise from various factors, with temperature being a crucial one. By correcting the errors induced by ambient temperature, the overall accuracy of the monitoring points can be significantly improved.
Article
Engineering, Electrical & Electronic
Hsiang-Chun Chuang, Chung-Wei Kung, Li-Wu Chen, Shyh-Biau Jiang
Summary: Magnetic encoders are commonly used in industrial manufacturing processes to control motors for precise positioning. This study analyzed the measurement error caused by the eccentricity of a magnetic encoder and developed a compensation method. An experimental calibration system with a two-phase stepping motor was used to provide a standard reference angle. The proposed method successfully improved the accuracy of a 14-bit magnetic encoder from 8-9 bits to 11-12 bits.
IEEE SENSORS JOURNAL
(2023)
Article
Nuclear Science & Technology
Shigetoshi Nakamura, Go Matsunaga, Manabu Takechi, Daigo Tsuru, Satoshi Yamamoto, Yutaro Itashiki, Takao Hayashi, Akihiko Isayama
Summary: Eighteen error field correction coils (EFCCs) made of copper conductor and epoxy resin are installed in the vacuum vessel of JT-60SA to correct magnetic fields caused by manufacturing and installation errors of superconducting coils. The support pedestals, made of stainless steel 316 L with NCF625 spring bars, need to withstand electromagnetic force and magnetic field during plasma operations, while allowing relative displacement between EFCC and the vacuum vessel during baking operations at different temperatures. The design of the spring bars and connection structure was determined through FEM analysis.
FUSION ENGINEERING AND DESIGN
(2021)
Review
Physics, Applied
M. Breschi, L. Cavallucci, H. Adeagbo, K. Sedlak, H. Bajas, A. Vostner, Y. Ilyin
Summary: The safe operation of joints is crucial for large scale magnets wound with cable-in-conduit conductors to ensure reliability and stability. Experimental campaigns have been conducted during the R & D activities for the ITER magnet system to study the performance of joints and mitigate the risk of thermal runaways. The investigation analyzes the performance of joints for the connection of the conductors of the PF coils of the ITER magnet system under different working conditions.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Nuclear Science & Technology
Francesco Maviglia, Leonardo Pigatto, Fabio Villone, Hartmut Zohm, Christopher Albert, Pierluigi Bruzzone, Rico Buchholz, Ben Drumm, Jonathan Gerardin, Yueqiang Liu, Cesar Luongo, Mattia Siccinio, Sven Wiesen
Summary: This work presents the initial studies on the requirements for the design of 3D coils on EU-DEMO. The results show that all the desired functions can be achieved by designing ex-vessel coils, using ITER tolerances for the TF, CS, and PF coils.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Computer Science, Hardware & Architecture
Yao-Ming Kuo, Francisco Garcia-Herrero, Oscar Ruano, Juan Antonio Maestro
Summary: Due to advances in new communication standards and quantum computing, there is a need for integrating processors into nodes to provide network flexibility, reduce costs, and support diverse services. This work proposes a versatile RISC-V Galois field ISA extension to integrate new and classical algorithms and achieve lower latency. The extension is implemented and validated using SweRV-EL2 1.3 on a Nexys A7 FPGA, resulting in a five-times acceleration for AES, Reed-Solomon codes, and Classic McEliece at a slight increase in logic utilization.
IEEE TRANSACTIONS ON COMPUTERS
(2023)
Article
Nuclear Science & Technology
Shusheng Wang, Ge Gao, Linsen Wang, Qian Jiang
Summary: This paper describes the development of the Static Magnetic Field (SMF) test facility for researching the magnetic field immunity of electrical and electronic components near the ITER Tokamak device. The facility includes the subsystems of the magnet coil, Equipment Under Test (EUT) Handling System (EHS), power supply system, and the control and acquisition system. Tests were carried out on the power supply system, magnet coil, and EHS system, and the results show that the SMF test facility meets the requirements of EUT magnetic field immunity with a maximum test magnetic field of 275 mT and a test area of 1 m3.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Computer Science, Artificial Intelligence
Romila Aziz, Muhammad Waqas Anwar, Muhammad Hasan Jamal, Usama Ijaz Bajwa
Summary: This paper introduces a Urdu Spell Checker that detects incorrect spellings of words using lexicon lookup and edit distance technique, and proposes a hybrid model for ranking candidate words. Multiple ranking techniques are used to determine the best candidate word, achieving high F1 scores.
NEURAL COMPUTING & APPLICATIONS
(2021)
Article
Thermodynamics
Ian Pope, Juan P. Hidalgo, Rory M. Hadden, Jose L. Torero
Summary: A study on the impact of thermocouples embedded in materials of lower thermal conductivity showed that the presence of thermocouples can distort the surrounding temperature field, leading to measurement errors. By analyzing key factors and using finite element models, it was found that thermal properties, geometry, and heating regime all affect the thermal disturbance.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Quantum Science & Technology
Ryuji Takagi, Suguru Endo, Shintaro Minagawa, Mile Gu
Summary: The article derives fundamental bounds on how error-mitigation algorithms can reduce computation errors, providing insights into optimizing and improving quantum error-mitigation strategies.
NPJ QUANTUM INFORMATION
(2022)
Article
Physics, Fluids & Plasmas
Kaijun Zhao, Yoshihiko Nagashima, Zhibin Guo, Patrick H. Diamond, Jiaqi Dong, Longwen Yan, Kimitaka Itoh, Sanae-I Itoh, Xiaobo Li, Jiquan Li, Akihide Fujisawa, Shigeru Inagaki, Jun Cheng, Jianqiang Xu, Yusuke Kosuga, Makoto Sasaki, Zhengxiong Wang, Huaiqiang Zhang, Yuqian Chen, Xiaogang Cao, Deliang Yu, Yi Liu, Xianming Song, Fan Xia, Shuo Wang
Summary: Enhancements of edge zonal flows, radial electric fields, and turbulence are observed in electron cyclotron resonance heating-heated plasmas. The effects of sawtooth heat pulses on flows and turbulence are presented. The delay time of the maximal intensity of the electric fields, zonal flows, and turbulence with respect to the sawtooth crashes is estimated as similar to 1 ms and comparable to that of the sawtooth-triggered intermediate phases.
PLASMA SCIENCE & TECHNOLOGY
(2023)
Article
Physics, Fluids & Plasmas
G. Z. Hao, G. Q. Dong, B. T. Cui, Y. Q. Liu, Y. H. Xu, T. F. Sun, X. Q. Ji, S. Wang, Y. F. Zhao, J. Q. Xu, X. Bai, N. Zhang, C. Y. Li, L. Wang, H. D. He, J. M. Gao, Yi Liu, W. L. Zhong, M. Xu, X. R. Duan
Summary: The divertor biasing technique, which uses divertor biasing current filaments to create field perturbations, offers a promising alternative for controlling the edge localized mode (ELM) and divertor heat load in tokamaks. Simulation results reveal that the technique can be applied to ELM control and reduce the chance of mode locking associated with core perturbations.
Article
Physics, Fluids & Plasmas
Guoliang Xia, Yueqiang Liu, T. C. Hender, K. G. McClements, E. Trier, E. Tholerus
Summary: This study uses the MARS-F/K codes to simulate the passive and active control of the n=1 resistive wall mode in a spherical tokamak. Passive control relies on plasma flow and drift kinetic resonance damping, while active control requires a flux-to-voltage control scheme with proportional and derivative controllers. The results show that the RWM can be fully stabilized with axial plasma flow at 5% of the Alfven speed, with success rates exceeding 90% in the presence of sensor signal noise.
Article
Physics, Fluids & Plasmas
Y. Q. Wang, G. Z. Hao, Y. P. Zou, Y. Q. Liu, W. Chen, G. M. Yang, G. Meng, Y. T. Miao, Y. F. Zhao, Y. B. Xia
Summary: The transport and loss of beam injected energetic particles due to three-dimensional perturbations in plasma with external kink instability and fishbone-like mode were studied numerically in HL-2A tokamak. The simulation results showed that when the XK-induced radial magnetic field perturbation exceeded a threshold value of about 10(-2), the profile of energetic particles experienced a significant change. The transport of energetic particles was dominated by diffusion instead of convection. Furthermore, when the resonance between the FLM and energetic particles occurred at a frequency above a threshold value of approximately 2 kHz, the redistribution and loss of energetic particles were substantially enhanced.
Article
Physics, Multidisciplinary
J. Gonzalez-Martin, M. Garcia-Munoz, J. Galdon-Quiroga, Y. Todo, J. Dominguez-Palacios, M. Dunne, A. Jansen van Vuuren, Y. Q. Liu, L. Sanchis, D. Spong, W. Suttrop, X. Wang, M. Willensdorfer
Summary: The suppression and excitation of Alfve'n eigenmodes in a tokamak plasma have been experimentally achieved for the first time using externally applied 3D perturbative fields with different spatial spectra. These perturbations cause a redistribution of fast ions in the plasma, altering the phase-space gradients that drive the modes and ultimately determining their existence. Simulations indicate that a resonant transport layer activated by the 3D perturbative field plays a role in the fast-ion redistribution. These findings are significant for controlling fast-ion driven Alfve'nic instabilities in future fusion plasmas.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Fluids & Plasmas
Lina Zhou, Yueqiang Liu, Hanqing Hu, Mattia Siccinio, Maviglia Francesco, Hartmut Zohm, Leonardo Pigatto, Yong Wang, Li Li, Guangzhou Hao, Xu Yang, Hanyu Zhang, Ping Duan, Long Chen
Summary: A systematic investigation is conducted on the plasma response to an externally applied RMP field in an EU DEMO reference plasma with the aim of controlling edge localized modes. The study focuses on the role of kinetic effects associated with both thermal particles and fusion-born alphas. The results show that the single fluid, resistive model predicts a large peak amplification of the plasma response, while a more advanced response model including kinetic resonances between RMP perturbation and drift motions of particles finds a strong suppression of the field amplification.
PLASMA PHYSICS AND CONTROLLED FUSION
(2023)
Article
Physics, Fluids & Plasmas
Guanming Yang, Yueqiang Liu, Zhibin Wang, Yongqin Wang, Yutian Miao, Guangzhou Hao
Summary: The redistribution of neutral beam injection (NBI) fast ions in ITER is studied, and it is found that both the internal kink and fishbone instabilities can cause transport of fast ions in real space. The transport of fast ions increases with the amplitude of the internal kink perturbation and the frequency of the fishbone instability. Perturbations with higher toroidal mode number lead to outward excursion of the fast ion transport regions.
PLASMA SCIENCE & TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
J. W. Li, L. Li, Y. Q. Liu, Y. F. Wang, P. Qin, Q. B. Luan, X. J. Huang, L. J. Guo, F. C. Zhong
Summary: A systematic numerical study using the MARS-F code is conducted to investigate the plasma response to the resonant magnetic perturbation (RMP) field applied for controlling edge localized modes (ELMs) in tokamak plasmas with varying aspect ratio. The results show a non-monotonic dependence of the resonant response field near the plasma edge with changing aspect ratio, indicating that certain aspect ratios are more favorable for ELM control. The optimal aspect ratio depends on the toroidal and poloidal spectra of the applied RMP field.
Article
Physics, Fluids & Plasmas
N. Zhang, Y. Q. Liu, D. L. Yu, Yi Liu, G. Z. Hao, L. Liu, X. X. He, T. F. Sun, X. Q. Ji, S. Wang, G. Q. Dong, X. Bai, Y. L. Wei, W. J. Chen, Y. W. Sun, M. Jiang, Y. P. Zhang, Z. B. Shi, W. L. Zhong, M. Xu
Summary: The effects of predominantly n=1 resonant magnetic perturbation (RMP) on plasma density and toroidal flow speed in the HL-2A tokamak were investigated. Simulation results showed that neoclassical toroidal viscosity (NTV) played a key role in modifying plasma momentum and particle transport. The electron NTV particle flux model, combined with free-boundary condition, yielded the best agreement with experimental results.
Article
Physics, Fluids & Plasmas
Xu Yang, Yueqiang Liu, Wei Xu, Yuling He, Guoliang Xia
Summary: The influence of negative triangularity (NT) on the stability of the n = 1 tearing mode (TM) has been investigated numerically. The TM near the plasma edge is found to be more unstable in NT plasmas compared to positive triangularity (PT) plasmas, due to the lack of favorable average curvature stabilization in NT configurations. However, in the core-localized TM, larger Shafranov shift in the plasma core associated with NT configuration results in more stable TM.
Article
Physics, Fluids & Plasmas
Cheng Ye, You-Wen Sun, Hui-Hui Wang, Yue-Qiang Liu, Tong-Hui Shi, Qing Zang, Tian-Qi Jia, Qun Ma, Shuai Gu, Nan Chu, Kai-Yang He, Man-Ni Jia, Xue-Min Wu, Peng-Cheng Xie, Hui Sheng, Hua Yang, Lian-Sheng Huang, Biao Shen, Miao-Hui Li, Jin-Ping Qian, EAST Team
Summary: The plasma-beta effect on the n=1 resonant magnetic perturbation (RMP) field penetration in purely radio-frequency (RF) wave heated discharges has been investigated. The experimental results show that the error-field tolerance is improved with increasing RF power, benefiting from the increased electron perpendicular flow dominated by a counter-current electron diamagnetic flow. However, the theoretical scaling overestimates the power index, and the degradation effect of plasma beta is observed.
Article
Physics, Fluids & Plasmas
H. Sheng, Y. W. Sun, X. Y. Li, H. H. Li, X. M. Wu, Y. Y. Li, S. F. Mao, Q. Ma, Y. Q. Liu, C. Ye, X. T. Yan, P. C. Xie, Q. Zang, H. H. Wang, M. N. Jia, M. Y. Ye
Summary: The spectrum effects on toroidal rotation braking induced by n = 1 resonant magnetic perturbations in EAST tokamak discharges were studied. The results showed that the effect is stronger in the discharge with lower q(95) = 4.1. Modeling of the neoclassical toroidal viscosity (NTV) torque based on magnetic perturbations agreed well with the experimentally observed braking torques in both discharges, indicating the capability of NTV theory in explaining the experimental observation in the EAST tokamak.
Article
Nuclear Science & Technology
T. G. Brown, J. E. Menard
Summary: A recent study by the U.S. National Academy recommended the development of a Sustained High Power Density (SHPD) facility in the U.S. as a step towards building a Pilot Plant device. This paper focuses on the architectural development of past activities to meet the requirements of a fusion pilot plant and power plant.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Nanoscience & Nanotechnology
G. Q. Dong, Y. Q. Liu, G. Z. Hao, S. Wang, N. Zhang, Y. Q. Wang, Y. T. Miao, C. Y. Li, Y. F. Zhao
Summary: This study systematically investigates the effects of 3D perturbations caused by an unstable n = 1 internal kink on the energetic particles in HL-2M tokamak. It is found that the 3D perturbation affects the EP drift orbit, confinement, and loss in HL-2M. The instability-induced EP loss is typically less than 10%, but the prompt orbit loss associated with the 2D equilibrium field reaches about 16% in HL-2M.
Article
Physics, Multidisciplinary
Zhou Li-Na, Hu Han-Qing, Liu Yue-Qiang, Duan Ping, Chen Long, Zhang Han-Yu
Summary: It is well known that large-scale type-I edge localized modes (ELMs) pose risks to machine components in future large fusion devices. Recent experiments have shown that resonant magnetic perturbations (RMPs) can suppress or mitigate ELMs. This study focuses on the roles played by the edge safety factor, RMP coil current, and particle drift kinetic effects. Computational simulations show that the plasma response exhibits periodic amplification as q95 varies and that the number of peaks is positively correlated with the toroidal number. The optimal/worst current phase difference and the optimal coil current amplitude can be well fitted by simple analytical models.
ACTA PHYSICA SINICA
(2023)