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Recent advances in the magnetic reconnection,dipolarization,and auroral processes at giant planets from the perspective of comparative planetology

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Earth and Planetary Physics 2024年第5期8卷 659-672页

作者： ZhongHua Yao ruilong guo Yong Wei Bertrand Bonfond Denis Grodent BinZheng Zhang William R.Dunn ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde LiègeB-4000 LiègeBelgium Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai Shandong 264209China Department of Earth Sciences the University of Hong KongPokfulamHong Kong SARChina Department of Physics and Astronomy University College LondonLondon WC1E 6BTUK School of Earth and Space Sciences Peking UniversityBeijing 100871China

Magnetic reconnection and dipolarization are crucial processes driving magnetospheric dynamics,including particle energization,mass circulation,and auroral processes,among *** studies have revealed that these processes at Saturn and Jupiter are fundamentally different from the ones at *** reconnection and dipolarization processes are far more important than previously expected in the dayside magnetodisc of Saturn and potentially *** magnetodisc reconnection was directly identified by using Cassini measurements(guo RL et al.,2018b)and was found to be drizzle-like and rotating in the magnetosphere of Saturn(Delamere et al.,2015b;Yao ZH et al.,2017a;guo RL et al.,2019).Moreover,magnetic dipolarization could also exist at Saturn’s dayside(Yao ZH et al.,2018),which is fundamentally different from the terrestrial *** new results significantly improve our understanding of giant planetary magnetospheric dynamics and provide key insights revealing the physics of planetary ***,we briefly review these recent advances and their potential implications for future investigations.

关键词： magnetosphere magnetic reconnection magnetic depolarization

Sawtooth and dune auroras simultaneously driven by waves around the plasmapause

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Earth and Planetary Physics 2023年第2期7卷 237-246页

作者： Fei He ZhongHua Yao BinBin Ni Xing Cao ShengYi Ye ruilong guo JinXing Li ZhiPeng Ren XinAn Yue YongLiang Zhang Yong Wei XiaoXin Zhang ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China Institute of Space Sciences Shandong UniversityWeihai Shandong 264209China Department of Atmospheric and Oceanic Sciences University of CaliforniaLos AngelesCaliforniaUSA Johns Hopkins University Applied Physics Laboratory LaurelMaryland 20723USA Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing 100081China Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

The dune aurora,at a scale of~30 kilometers,was reported recently using ground *** small-scale dune aurora occurs on the duskside and exhibits a monochromatic oscillation in the auroral emission,implying fundamental energy ***,whether the dune auroras correspond to atmospheric waves or are associated with magnetospheric dynamics should be *** paper reports a dune aurora that occurred during a storm;further,we demonstrate that it was the substructure of the sawtooth aurora that was generated by plasmapause surface *** observations in the magnetospheric source region suggest that the exohiss waves,which are periodically modulated by the plasmapause surface wave-excited ultralow frequency wave,might be responsible for the generation of the dune *** reported dune aurora events have occurred simultaneously with sawtooth auroras,suggesting that both are plasmapause-driven cross-scale auroral structures.

关键词： sawtooth aurora dune aurora plasmapause surface wave exohiss

Propagation properties of foreshock cavitons: Cluster observations

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Science China(Technological Sciences) 2020年第1期63卷 173-182页

作者： WANG MengMeng YAO ShuTao SHI QuanQi ZHANG Hui TIAN AnMin DEGELING Alexander William ZHANG Shuai guo ruilong SUN WeiJie LIU Ji BAI ShiChen SHEN XiaoChen ZHU XiaoQiong FU SuiYan PU ZuYin School of Space Science and Physics Shandong UniversityWeihai 264209China National Space Science Center Chinese Academy of SciencesBeijing 100190China Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Department of Climate and Space Sciences and Engineering University of MichiganAnn Arbor 48113USA Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

Foreshock cavitons are transient phenomena observed in the terrestrial foreshock *** are characterized by a simultaneous depression of magnetic field magnitude and plasma density,which are bounded with enhancements of these two parameters and surrounded by ultralow frequency(ULF)*** studies focused on the interplanetary magnetic field(IMF)conditions,solar wind(SW)conditions,and the growth of the foreshock waves related to the generation of foreshock ***,a multipoint spacecraft analysis method using Cluster data was applied to analyze only two foreshock cavitons,and this method did not consider *** this study,multipoint spacecraft analysis methods,including the timing method,the minimum directional derivative(MDD)method,and the spatiotemporal difference(STD)method are applied to determine the velocity in both spacecraft and solar wind *** propagation properties show good agreement with previous results from simulations and observations that most cavitons move sunward in the solar wind frame,with the velocities larger than the Alfvén *** propagation properties of foreshock cavitons support the formation mechanism of cavitons in previous simulations,which suggested that cavitons are formed due to the nonlinear evolution of compressive ULF *** find that there is clear decreasing trend between the size of cavitons and their velocity in the solar wind *** addition,the timing method considering errors has been applied to study the evolution properties by comparing the velocities with errors of the leading and trailing edges,and we identify three stable cavitons and one contracting caviton,which has not been studied *** cavitons should remain stable when they travel toward the Earth’s bow *** relationship between the size of foreshock cavitons and their distance from the bow shock is also discussed.

关键词： foreshock transient phenomena cavitons nonlinear evolution of ULF waves propagation and evolution properties of structures multipoint spacecraft methods

Evolution of clustered magnetic nulls in a turbulent-like reconnection region in the magnetotail

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Science Bulletin 2016年第24期61卷 1145-1150页

作者： ruilong guo Zuyin Pu Suiyan Fu Lun Xie Malcolm Dunlop Yulia V. Bogdanova Jiansen He Xin Wang Zhonghua Yao School of Earth and Space Sciences Peking UniversityBeijing 100871 China PKU/UCLA Joint Research Institute in Science and Engineering Peking University Beijing 100871 China School of Astronautics Beihang University Beijing 100191China RAL Space Rutherford Appleton Laboratory STFCDidcot OXll 0QX UK UCL Mullard Space Science Laboratory Dorking RH5 6NT UK

t Magnetic null points and flux ropes play important roles in the three-dimensional process of magnetic reconnection. In this study, a cluster of null points are reconstructed in the reconnection region in the magnetotail by applying a fitting-reconstruction method to measurements from the Cluster mission. The number of recon- structed null points varies rapidly, presenting a turbulentlike evolution of the magnetic structure. The electron density and the flux of the accelerated electrons were enhanced in this turbulent-like region. During this unstable reconnection process, a B-As-B null structure was formed, showing flux rope features and resembling a secondary island in the observation.

关键词： Magnetic reconnection - Turbulent Magnetic null point Flux ropes Magnetotail

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Statistical properties of kinetic-scale magnetic holes in terrestrial space

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Earth and Planetary Physics 2021年第1期5卷 63-72页

作者： ShuTao Yao ZongShun Yue QuanQi Shi Alexander William Degeling HuiShan Fu AnMin Tian Hui Zhang Andrew Vu ruilong guo ZhongHua Yao Ji Liu Qiu-Gang Zong XuZhi Zhou JingHuan Li WenYa Li HongQiao Hu YangYang Liu WeiJie Sun Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai Shandong 264209China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Space and Environment Beihang UniversityBeijing 100191China Physics Department and Geophysical Institute University of Alaska FairbanksFairbanksAK99775USA Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde LiègeLiègeB-4000Belgium School of Earth and Space Sciences Peking UniversityBeijing 100871China SOA Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China Department of Climate and Space Sciences and Engineering University of MichiganAnn ArborMI48109USA

Kinetic-scale magnetic holes(KSMHs)are structures characterized by a significant magnetic depression with a length scale on the order of the proton *** structures have been investigated in recent studies in near-Earth space,and found to be closely related to energy conversion and particle acceleration,wave-particle interactions,magnetic reconnection,and turbulence at the ***,there are still several major issues of the KSMHs that need further study—including(a)the source of these structures(locally generated in near-Earth space,or carried by the solar wind),(b)the environmental conditions leading to their generation,and(c)their spatio-temporal *** this study,KSMHs in near-Earth space are investigated statistically using data from the Magnetospheric Multiscale *** 200,000 events were observed from September 2015 to March *** rates of such structures in the solar wind,magnetosheath,and magnetotail were *** find that KSMHs occur in the magnetosheath at rates far above their occurrence in the solar *** indicates that most of the structures are generated locally in the magnetosheath,rather than advected with the solar ***,KSMHs occur in the downstream region of the quasi-parallel shock at rates significantly higher than in the downstream region of the quasi-perpendicular shock,indicating a relationship with the turbulent plasma *** to the magnetopause,we find that the depths of KSMHs decrease as their temporal-scale *** also find that the spatial-scales of the KSMHs near the subsolar magnetosheath are smaller than those in the ***,their global distribution shows a significant dawn-dusk asymmetry(duskside dominating)in the magnetotail.

关键词： kinetic scale magnetic hole magnetic dip electron vortex turbulence

Model-based frequency optimization for frequency-tunable superconducting processors

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Science China(Physics,Mechanics & Astronomy) 2025年第2期Mechanics & Astronomy) .卷 197-198页

作者： Qiujiang guo ZJU-Hangzhou Global Scientific and Technological Innovation Center School of PhysicsZhejiang University

Over the past twenty years, superconducting quantum computation has become one of the most promising candidates leading to fault-tolerant quantum computers. This is largely due to the huge experimental progress on improving coherence time, qubit number, and control accuracy on recent superconducting processors. In particular, frequency-tunable two-dimensional architecture and well-established device fabrication processes allow us to scale up the system size of superconducting processors while maintaining the quality of each qubit.

关键词： superconducting quantum optimization

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不同日粮组成对围产期奶牛泌乳性能和乳品质的影响

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养殖与饲料 2023年第8期22卷 9-12页

作者：郭瑞龙山东省费县农业农村局农业技术推广中心山东费县273400

[目的]研究不同日粮组成对围产期奶牛泌乳性能和乳品质的影响,确定适合围产期奶牛的适宜精粗比日粮组成,为提高围产期奶牛生产性能和养殖经济效益提供依据。[方法]将30头围产前期荷斯坦奶牛随机分为3组(A、B、C组),每组10头,A、B、C组... 详细信息

[目的]研究不同日粮组成对围产期奶牛泌乳性能和乳品质的影响,确定适合围产期奶牛的适宜精粗比日粮组成,为提高围产期奶牛生产性能和养殖经济效益提供依据。[方法]将30头围产前期荷斯坦奶牛随机分为3组(A、B、C组),每组10头,A、B、C组饲喂精饲料与粗饲料比列分别为40∶60、50∶50、60∶40的全混合日粮,测定平均日采食量、平均日产奶量、料奶比等泌乳性能检测指标和乳脂率、乳蛋白率、乳糖率、体细胞数等乳品质检测指标。[结果]B组与A组相比,平均日采食量、平均日产奶量、乳蛋白率均显著提高,牛奶体细胞数显著降低;C组与A组相比,平均日采食量、平均日产奶量、乳脂率、乳蛋白率、乳糖率均显著提高,料奶比、牛奶体细胞数均显著降低;C组与B组相比,平均日产奶量、乳蛋白率均显著提高,牛奶体细胞数显著降低。[结论]随着围产期奶牛日粮中精饲料所占比例的逐步提高,围产期奶牛的泌乳性能和乳品质逐渐提高。

关键词：日粮组成围产期奶牛泌乳性能乳品质

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Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 60-66页

作者： guo-Fu Xu Department of Physics Shandong UniversityJinan 250100China

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era,building accurate intermediate-scale nonadiabatic holo-nomic quantum computers is clearly *** that measurements are the sole means of extracting information,they play an indispensable role in nonadiabatic holonomic quantum ***,developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great ***,while much attention has been given to the research on nonadiabatic holonomic gates,the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely *** this study,we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum *** reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic *** these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

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一种基于行为关联的主机系统入侵检测方法

高技术通讯 2012年第9期22卷 897-903页

作者：王映龙李京春王少杰锁延锋梁利郭瑞龙江西农业大学软件学院南昌330045 国家信息技术安全研究中心北京100084 北京科技大学信息工程学院北京100083

提出了一种基于主机行为解析和行为关联分析的主机系统入侵检测方法，对嵌入式恶意软件具有较高的检测效率，可应用于基于网络行为的入侵检测系统。通过对行为进行深层次的解析，建立了行为间的关联关系模型，在降低存储异常行为样本规... 详细信息

提出了一种基于主机行为解析和行为关联分析的主机系统入侵检测方法，对嵌入式恶意软件具有较高的检测效率，可应用于基于网络行为的入侵检测系统。通过对行为进行深层次的解析，建立了行为间的关联关系模型，在降低存储异常行为样本规模的同时，提高了该方法的灵活性和应用范围。实验结果显示，与现有的异常行为检测方法相比，该方法需要较长的训练时间，但是，通过调整行为粒度，该方法可以使训练时间保持在合理的范围之内。随着时间的推进，该方法的性能将逐步提高，在漏报率、误报率及更新效率上，较现有系统都有较大的提高。

关键词：关联分析主机系统入侵检测系统(IDS)