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The azimuthal currents in the ion-driven magnetic nozzle

Propulsion and Power Research 2022年第4期11卷 457-472页

作者： Zhiyuan Chen Yibai wang haibin Tang Junxue Ren Min Li Peng Wu Jinbin Cao School of Astronautics Beihang UniversityBeijing102206China Key Laboratory of Spacecraft Design Optimization and Dynamic Simulation Technologies Ministry of EducationBeijing102206China Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing102206China Innovation Academy of Microsatellites Chinese Academy of SciencesShanghai201203China School of Space and Environment Beihang UniversityBeijing102206China

Ion-driven magnetic nozzles(Ti>Te)are designed as intrinsic parts of cutting-edge propulsive technologies such as variable specific impulse magnetoplasma rockets(VASIMRs)and applied-field magnetoplasmadynamic thrusters.Employing a two-dimensional axisymmetric particle-in-cell(PIC)code,in the ion-driven magnetic nozzle,the compositions and distributions of azimuthal currents in different axial regions are investigated under various inlet ion temperatures Ti0 and found to differ dramatically from that in the electron-driven magnetic nozzles.Previously reported to be all paramagnetic and vanishing under a high magnetic field,the azimuthal currents resulting from the E 3 B drift are shown to turn diamagnetic and sustain a considerable magnitude when Ti0 is considered.The previously reported profile of diamagnetic drift current is altered by the introduction of inlet ion temperature,and the paramagnetic part is significantly suppressed.Moreover,a wide range of paramagnetic currents appear downstream due to the inward detachment of ions,which can also be reduced by increasing inlet ion temperature.Albeit considered in this paper,the azimuthal currents resulting from grad-B and curvature drift are still negligible in all cases of interest.The magnitude of diamagnetic azimuthal currents increases with amplifying Ti0,indicating a clear physical image of energy transformation from ion thermal energy to the directed kinetic energy through electromagnetic processes in the magnetic nozzle.Additionally,the magnetic inductive strength also has noticeable impacts on the azimuthal currents,the current magnitude tends to decrease as the magnetic field increases,and over-increment of it may result in larger divergence angles and lower nozzle efficiency.

关键词： Magnetic nozzle Azimuthal current Ion temperature Electric propulsion

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精神的实现与现实的精神:从黑格尔到马克思

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北京大学学报（哲学社会科学版） 2021年第1期58卷 42-49页

作者：王海滨中共中央党校(国家行政学院)马克思主义学院北京100091

经历了对黑格尔精神实现论的追随和批判之后,在马克思以实践为基石的历史唯物主义视野中,精神成为社会结构的一部分,精神解放成为实践的一个环节。在对资本现代性的总体性批判中,马克思深入批判了感性至上和欲望主宰的现代原则、嵌入精... 详细信息

经历了对黑格尔精神实现论的追随和批判之后,在马克思以实践为基石的历史唯物主义视野中,精神成为社会结构的一部分,精神解放成为实践的一个环节。在对资本现代性的总体性批判中,马克思深入批判了感性至上和欲望主宰的现代原则、嵌入精神领域的"抽象统治",以及现代性的"双重虚无"状态。沿着马克思开辟的精神哲学道路,在"现代化·欲望·精神"的整体性框架中,可以从八个相辅相成的环节探寻走出现代性精神困境之路:精神与现代化的沟通互动、生产力容许范围内的精神自由、社会关系决定下人的发展程度、从"异化劳动"到"真正自由的劳动"、以观念变革为核心的内在世界转型、自由时间是人的积极存在、以真正的共同体为空间舞台、精神与欲望协和的境界。

关键词：黑格尔马克思现代性欲望精神

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Interactivemedical image segmentation with self-adaptive confidence calibration

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信息与电子工程前沿:英文版 2023年第9期24卷 1332-1348页

作者： Chuyun SHEN Wenhao LI Qisen XU Bin HU Bo JIN haibin CAI Fengping ZHU Yuxin LI Xiangfeng wang School of Computer Science and Technology East China Normal UniversityShanghai 200062China Huashan Hospital Fudan UniversityShanghai 200040China Software Engineering Institute East China Normal UniversityShanghai 200062China

Interactive medical image segmentation based on human-in-the-loop machine learning is a novel paradigm that draws on human expert knowledge to assist medical image segmentation.However,existing methods often fall into what we call interactive misunderstanding,the essence of which is the dilemma in trading off short-and long-term interaction information.To better use the interaction information at various timescales,we propose an interactive segmentation framework,called interactive MEdical image segmentation with self-adaptive Confidence CAlibration(MECCA),which combines action-based confidence learning and multi-agent reinforcement learning.A novel confidence network is learned by predicting the alignment level of the action with short-term interaction information.A confidence-based reward-shaping mechanism is then proposed to explicitly incorporate confidence in the policy gradient calculation,thus directly correcting the model’s interactive misunderstanding.MECCA also enables user-friendly interactions by reducing the interaction intensity and difficulty via label generation and interaction guidance,respectively.Numerical experiments on different segmentation tasks show that MECCA can significantly improve short-and long-term interaction information utilization efficiency with remarkably fewer labeled samples.The demo video is available at https://bit.ly/mecca-demo-video.

关键词： Medical image segmentation Interactive segmentation Multi-agent reinforcement learning Confidence learning Semi-supervised learning

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海外油气资产并购中的储量评估研究

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中国石油勘探 2022年第3期27卷 149-154页

作者：王建毕海滨中国海洋石油国际公司中国石油勘探开发研究院

海外油气资产并购的核心是储量。资源国使用的标准不同,评估的储量结果差异很大,如不能准确把握,将给资产并购带来极大风险。文章重点分析了国际通用资源/储量分类标准的内涵及储量的不确定性,并以实际案例分析为纽带,结合海外油气资产... 详细信息

海外油气资产并购的核心是储量。资源国使用的标准不同,评估的储量结果差异很大,如不能准确把握,将给资产并购带来极大风险。文章重点分析了国际通用资源/储量分类标准的内涵及储量的不确定性,并以实际案例分析为纽带,结合海外油气资产评价方面存在的诸多挑战,提出海外油气资产并购评价的“两个加强”和“两个坚持”,加强资源国的资源/储量分类研究,明确储量内涵;加强海外油气储量数据库建设,支撑快速类比评价;坚持“不确定性”评价原则,合理预判资源风险;坚持“全生命周期”评价原则,客观认识资源潜力。

关键词：海外油气资产资产并购储量不确定性储量评估

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俄罗斯的阿富汗政策:调整、动因与展望

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现代国际关系 2020年第10期 10-17,61页

作者：王海滨陕西师范大学哲学与政府管理学院

俄罗斯近期对阿富汗政策进行了一系列调整:不再奉行反塔利班政策而是与其对话及有限合作;主张通过政治手段解决阿富汗问题,支持美国与塔利班达成和平协议;作为独立于美国之外的重要国际力量,愈发积极、主动地推进阿富汗民族和解进程;在... 详细信息

俄罗斯近期对阿富汗政策进行了一系列调整:不再奉行反塔利班政策而是与其对话及有限合作;主张通过政治手段解决阿富汗问题,支持美国与塔利班达成和平协议;作为独立于美国之外的重要国际力量,愈发积极、主动地推进阿富汗民族和解进程;在应对来自阿富汗的非传统安全威胁方面,不再寄希望于美国并公开督促美军撤离阿富汗,同时日益重视加强上海合作组织、集体安全条约组织及与盟友的安全合作。国际局势和阿富汗形势的变化,及俄罗斯对阿富汗问题认知的改变,是俄罗斯调整阿富汗政策的主要动因。俄罗斯近期阿富汗政策取得一定成果,但俄罗斯凭自己的实力、威望和影响难以实现其在阿富汗问题上的战略诉求。未来,俄罗斯将通过保持和加强与阿富汗各政治力量的接触与合作,以及继续寻求国际合作,巩固及提升其对阿富汗问题的影响力。

关键词：俄罗斯阿富汗莫斯科进程民族和解

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tsrCert:Traceable Self-Randomization Certificate and Its Application to Blockchain Supervision

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Tsinghua Science and Technology 2023年第6期28卷 1128-1147页

作者： Yan Zhu haibin Zheng Bo Qin Wanting Fu Zhenwei Guo Yujue wang Qianhong Wu Bingyu Li Xuan Ding School of Cyber Science and Technology Beihang UniversityBeijing 100191China Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China Key Laboratory of Cryptography of Zhejiang Province Hangzhou Normal UniversityHangzhou 311121China School of Information Renmin University of ChinaBeijing 100872China School of Software and BNRist Tsinghua UniversityBeijing 100084China

Traditional public key infrastructure(PKI)only provides authentication for network communication,and the standard X.509 certificate used in this architecture reveals the user’s identity.This lack of privacy protection no longer satisfies the increasing demands for personal privacy.Though an optimized anonymous PKI certificate realizes anonymity,it has the potential to be abused due to the lack of identity tracking.Therefore,maintaining a balance between user anonymity and traceability has become an increasing requirement for current PKI.This paper introduces a novel traceable self-randomization certificate authentication scheme based on PKI architecture that achieves both anonymity and traceability.We propose a traceable self-randomization certificate authentication scheme based on the short randomizable signature.Specifically,certificate users can randomize the initial certificate and public key into multiple anonymous certificates and public keys by themselves under the premise of traceability,which possesses lower computational complexity and fewer interactive operations.Users can exhibit different attributes of themselves in different scenarios,randomizing the attributes that do not necessarily need to be displayed.Through security and performance analysis,we demonstrate the suitability of the improved PKI architecture for practical applications.Additionally,we provide an application of the proposed scheme to the permissioned blockchain for supervision.

关键词： public key infrastructure traceable self-randomization certificate randomizable signature anonymity and traceability blockchain supervision

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Rodent-mediated plant community competition:what happens to the seeds after entering the adjacent stands?

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Forest Ecosystems 2020年第4期7卷 746-759页

作者： haibin Kang Mingjie Chang Shutong Liu Zhi Chao Xinping Zhang Dexiang wang College of Forestry Northwest A&F UniversityYangling 712100China. College of Art and Design Xi’an University of TechnologyXi’an 710054China.

Background:Seed dispersal by scatter-hoarding animals can affect the developmental dynamics of plant communities.However,how animals might participate in plant inter-community competition has rarely been investigated.Forest community junction is an area where the competition between plant communities is most prominent and animal activity is more frequent.At present,little is known about how scatter-hoarding animals might assist competitions by adjacent plant communities.Thus,for 3 years(2015–2017),we tracked the fate of 2880 tagged seeds(Quercus aliena var.acuteserrata,Pinus tabuliformis,and P.armandii seed)placed near an edge where the forest composition changes from a pine forest to an oak forest in northwestern China.Results:We found that the seed fates differed when Quercus and Pinus seeds entered adjacent stands.In contrast to Pinus seeds,acorns that entered pine forests were characterized by higher caching rates and longer dispersal distances.Pinus seeds had the highest probability of being predated(85%)by rodents,and eleven Q.aliena var.acuteserrata seedlings were established in pine forests,although none survived in the later stages.In addition,rodents exhibited obvious selectivity in terms of the microhabitats for the seed caching sites.Conclusions:Seed fates differed when Quercus and Pinus seeds entered adjacent stands.The predation pressure by rodents on the seeds of Pinus species limited the germination of seeds and seedling establishment in oak forests.The different seed fates after their bidirectional dispersal could affect the differences in natural regeneration between pine and oak forests,and they might increase the recruitment rates for oak at the edge of an adjacent community.Rodent-mediated seed dispersal could potential unintentionally affect the competition between plant communities.

关键词： Pine-oak mixed forest Plant community competition Scatter hoarding Seed dispersal Small rodent

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现代性反思视角下的中国道路

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文史哲 2020年第3期 20-25,165页

作者：王海滨中共中央党校(国家行政学院)马克思主义学院北京100091

现代性道路的多线论,是我们从学理上谈论中国道路的逻辑前提。西方现代化历程在文化理念、生存方式、经济逻辑和政治路径等层面均溢出了其负效应。西方现代性实践的负效应不是现代性本身必然带来的。中国道路应自觉反思西方现代性实践... 详细信息

现代性道路的多线论,是我们从学理上谈论中国道路的逻辑前提。西方现代化历程在文化理念、生存方式、经济逻辑和政治路径等层面均溢出了其负效应。西方现代性实践的负效应不是现代性本身必然带来的。中国道路应自觉反思西方现代性实践中可以避免的发展代价,走既充分借鉴现代性文明因素又最大限度地避免现代性负效应的道路。从理论上展望中国道路的前景,应自觉建构传统与现代相综合,物质与精神并重,党的领导下动力机制、平衡机制和优化机制相结合的新型文明形态。

关键词：现代性多元现代性东亚现代性多线论中国道路新型文明形态

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Rediscovery of the abyssal species Peniagone leander Pawson and Foell,1986(Holothuroidea:Elasipodida:Elpidiidae):the first record from the Mariana Trench area

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Journal of Oceanology and Limnology 2020年第4期38卷 1319-1327页

作者： GONG Lin LI Xinzheng XIAO Ning HE Lisheng ZHANG haibin wang Yong Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266200China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Department of Life Science Institute of Deep-sea Science and EngineeringChinese Academy of SciencesSanya 572000China

The elpidiid holothurian Peniagone leander Pawson and Foell,1986 is recorded for the first time from the Mariana Trench area at a depth of 5571 m.The type description of this species was based on only in-situ photographs.P.leander is re-described and illustrated based on a preserved material and in-situ photographs taken on the seabed.The 16S rRNA was also obtained from the specimen and submitted to GenBank.This is the fourth discovery of this species,extending its bathymetric range in the western Pacific Ocean.

关键词： Elpidiidae abyssal zone deep-sea holothurian benthopelagic species new record

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Synthesis,microstructure,and formation mechanism of a potential neutron shielding material:WAlB

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Journal of Materials Science & Technology 2022年第31期126卷 127-131页

作者： Dongya Zhang Peter Richardson Meng wang Hanjun Tu Cong Li Linping He haibin Zhang Liqun Shi Applied Ion Beam Physics Laboratory Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Engineering The University of NewcastleUniversity DriveCallaghanNSW2308Australia Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The recent re-discovery of nano-laminated,ternary transition metal borides called‘MAB’phases(M=transition metal,A=Al,and B=B)has allowed for an alternative candidate material for certain high-performance applications[1,2].The discovery of de-sirable MAB phase properties including near-room temperature magnetocaloric effects of Fe 2 AlB 2[3],high-temperature oxidation resistance of MoAlB[4],and single-layer 2D molybdenum boride sheets obtained through the chemical exfoliation of laminated compounds has resulted in an increase in research into their syn-thesis and properties[5].

关键词： microstructure resistance laminated

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