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Close relationship between the East Asian westerly jet and Russian far East surface air temperature in summer

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Atmospheric and Oceanic Science Letters 2018年第3期11卷 282-286页

作者： lin xiao-Zhen LI Chao-fan lin Zhong-Da LU Ri-Yu State Key Laboratory of Numerical Modelling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of Sciences

The interannual variability of the east asian upper-tropospheric westerly jet（EAJ） in summer is characterized by the meridional displacement of its axis, or a seesaw pattern of zonal wind anomalies between the northern and southern flanks of the EAJ. This study reveals a close relationship between the surface air temperature in the russian far east and the northern flank of the EAJ. Related to a warmer surface in the russian far east, the westerly decelerates in the northern flank of the EAJ. The relationship can be explained by a positive feedback mechanism between the surface air temperature in the russian far east and the overhead circulation： the anticyclonic circulation anomaly related to a weakened westerly in the northern flank of the EAJ induces surface warming in the russian far east and the warmer surface can in turn act as a heat source and induces a local anticyclonic circulation anomaly in the upper troposphere, therefore decelerating the westerly in the northern flank of the EAJ. The result implies that a better description of the summer surface condition in the russian far east may benefit seasonal forecasts of the EAJ and, subsequently, east asian summer climate.

关键词： East Asian westerly jet surface air temperature Russian far East

Shaping free-electron radiation via van der Waals heterostructures

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Light(Science & Applications) 2023年第8期12卷 1457-1458页

作者： xiao lin Hongsheng Chen Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and InstrumentationZJU-Hangzhou Global Scientific and Technological Innovation CenterCollege of Information Science&Electronic EngineeringZhejiang UniversityHangzhou 310027China international Joint Innovation Center the Electromagnetics Academy at Zhejiang UniversityZhejiang UniversityHaining 314400China Key Laboratory of Advanced Micro/Nano Electronic Devices&Smart Systems of Zhejiang Jinhua Institute of Zhejiang UniversityZhejiang UniversityJinhua 321099China Shaoxing Institute of Zhejiang University Zhejiang UniversityShaoxing 312000China

The van der Waals heterostructures with aperiodic stackings have been exploited to shape the spatiotemporal wavefront of free-electron X-ray radiation.

关键词： free stacking exploit

A Microstructural Damage Model toward Simulating the Mullins Effect in Double-Network Hydrogels

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Acta Mechanica Solida Sinica 2022年第4期35卷 682-693页

作者： lin Zhan Rui xiao State Key Laboratory of Fluid Power and Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering MechanicsZhejiang UniversityHangzhou310027China

The damage models based on the eight-chain model and the affine full-chain network model are not adequate to describe the damage behaviors in double-network(DN)*** overcome this limitation,we propose a combined chain stretch model with new damage flow *** is demonstrated that the new proposed micro-chain stretch is a reduced form of the complete representation for the transversely isotropic tensor *** a result,the damage models based on the eight-chain model and the affine model are incorporated as special *** effects of chain affineness and network entangling are simultaneously involved in the new model,while only one of these two effects can be characterized in either the eight-chain model or the affine *** is further shown that the new model can effectively capture the Mullins features of the DN hydrogels and achieve better agreement with the experimental data than the affine model and the eight-chain model.

关键词： Mullins effect Double-network hydrogel Full-network model Microstructural model

Structural and Operational Optimization of A Flapping Fin Used as A Self-Propulsor for AUV Propulsion

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China Ocean Engineering 2022年第1期36卷 86-99页

作者： fan Shuang-shuang CI xiao-han Neil BOSE CHENG xiao School of Marine Sciences Sun Yat-sen UniversityZhuhai 519082China Southern Laboratory of Ocean Science and Engineering Zhuhai 519000China Department of Ocean and Naval Architectural Engineering Memorial University of NewfoundlandSt.John’sNL A1C 5S7Canada School of Geospatial Engineering and Science Sun Yat-sen UniversityZhuhai 519082China

Marine mammals could directly harvest energy from waves and obtain propulsive force through oscillating flapping fins or horizontal tail flukes,which in many cases have been observed and proved to be *** propulsion generated by the flapping fin has been analyzed by many researchers from both the theoretical and experimental prospects;however,the structural and operational optimization of a flapping fin for the optimal propulsion performance has been less studied,such as the investigation of the effects of the phase difference between heave and pitch motion,maximum oscillation angle,fin shape,oscillation centre of the fin and the operating sea state on the generated *** this paper,the flapping fin is used as a self-propulsor to propel an autonomous underwater vehicle(AUV)for propulsion *** the optimization design of the flapping fin,its propulsion effect is numerically investigated with different structural parameters and under various operation conditions using computational fluid dynamics(CFD)*** and validation study have been implemented to quantify the numerical uncertainties and evaluate the accuracy of the proposed CFD ***,a series of case studies are thoroughly conducted to investigate the effects of different structural parameters and operational conditions on the generated propulsion of a flapping fin by CFD *** simulation results demonstrate that different structural parameters and operation conditions would significantly impact the magnitude and distribution state of the fluid pressure around the flapping fin surface,thus,affect the propulsion performance of the *** findings in this study will provide guidelines for the structural and operational optimization design of a flapping fin for self-propulsion of mobile platforms.

关键词： autonomous underwater vehicle(AUV) flapping fin self-propulsion computational fluid dynamics(CFD) optimization design

Magnetic correction to the anomalous magnetic moment of electrons

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Communications in Theoretical Physics 2022年第5期74卷 75-85页

作者： fan lin Mei Huang School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

We investigate the leading order correction of anomalous magnetic moment(AMM) to electrons in a weak magnetic field and find that the magnetic correction is negative and magnetic field dependent, indicating a magnetic catalysis effect for the electron gas. In the laboratory, to measure the g-2, the magnitude of the magnetic field B is several T, and correspondingly the magnetic correction to the AMM of electron/muon is around 10^(-34)/10^(-42), therefore the magnetic correction can be safely neglected in the current measurement. However, when the magnitude of the magnetic field strength is comparable with the electron mass, the magnetic correction of the electron’s AMM will become considerable. This general magnetic correction to the charged fermion’s AMM can be extended to study quantum chromodynamic matter under a strong magnetic field.

关键词： anomalous magnetic moment magnetic correction magnetic field

A NON-linEAR MODEL FOR ESTIMATING THE COST OF ACHIEVING EMISSION REDUCTION TARGETS:THE CASE OF THE U.S.,CHINA AND INDIA

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Journal of Systems Science and Systems Engineering 2012年第3期21卷 297-315页

作者： Lei ZHU xiao-Bing ZHANG Ying fan Center for Energy & Environmental Policy Research Institute of Policy and Management Chinese Academy of Sciences Beijing 100190 China Department of Economics University of Gothenburg SE 40530 G teborg Sweden

With the world talking about climate change, the United States （U.S.）, China and India have announced their carbon emission reduction targets. For these three countries to achieve their targets, significant questions arise, shch as what will be the annual emission reduction efforts to achieve those targets, how much it would cost and what would be the economic effects. This paper puts the carbon intensity reduction targets of China and India together with the absolute emission reduction target of the U.S. into the same non-linear model to quantitatively study the optimal emission control strategies and associated total cost for achieving those targets by the year 2020, and estimate and compare the minimized total costs of the three countries to reach their targets. Our results show that the total cost for the U.S. to achieve its emission reduction target is greater than those of China and India in terms of absolute amount. However, in terms of proportion of total cost to GDP, China and India＇s ratios are significantly greater than that of the U.S., indicating that for the developing countries such as China and India, the achievement of emission reduction targets needs relatively greater effort.

关键词： Emission reduction cost analysis emission reduction strategy optimization model

体育专业毕业生就业政策执行困境与创新路径——基于23份国家级公共政策文本的分析

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哈尔滨体育学院学报 2025年第1期43卷 17-24+32页

作者：姚小林韩冰哈尔滨体育学院体育人文与社会学院东北林业大学体育部

国家政策的有效执行是推动多方协同发力提升体育专业毕业生就业质量的实然命题。采用文献资料法和内容分析法，对体育专业毕业生就业政策执行因素、困境以及创新路径进行探讨。研究认为，基于史密斯政策执行过程模型，体育专业毕业生就... 详细信息

国家政策的有效执行是推动多方协同发力提升体育专业毕业生就业质量的实然命题。采用文献资料法和内容分析法，对体育专业毕业生就业政策执行因素、困境以及创新路径进行探讨。研究认为，基于史密斯政策执行过程模型，体育专业毕业生就业政策执行受理想化政策、执行机构、目标群体和环境因素等影响，执行困境具体表现在政策设计针对性不足、机构和人员执行不到位、目标群体认知存在偏差、政策执行环境不健全等方面。对此，未来应完善顶层设计，强化政策体系；强化执行能力，提升责任意识；健全服务体系，提高就业能力；优化教育环境，规范市场环境。

关键词：体育专业大学生就业政策执行政策文本分析

The codes of matter and their applications

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Science Bulletin 2015年第19期60卷 1661-1673页

作者： xiao-lin Wang Spintronic and Electronic Materials Group Institute for Superconducting and Electronic Materials Australia Institute for Innovative Materials University of Wollongong

The elements in the periodic table are the building blocks used to form substances with different compositions. Nevertheless, it is the properties of substances that are decisive for their existence and practical applications. Searching for new class of materials with exotic properties has always been challenging because of the complexity of both the theoretical and the experimental approaches developed so far. Here, we propose that the three ubiquitous and paramount attributes of all existing matter charge(Q), spin(S) or rotational motion, and linear motion(K) can be used to account for the formation of different types of matter/materials and their properties that have been or will be known to us. The three attributes or original codes can produce six primary codes which can further produce another sixty codes. The physical meanings represented by each code are unlocked. The table consisting of the 60 codes is introduced as the table of properties of codes of matter. We demonstrate that these codes can be used as building blocks to form new properties and new materials. Many new types of quasiparticles and new classes of materials with exotic properties of Q, S and K are predicted. Their possible experimental realizations are proposed. The possible applications of the codes of matter in other fields such as elementary particles, photonics and chemistry are briefly discussed. We know that there should be more new materials and new electronic, spin and photonic states to be discovered, but we do not know what they are. The codes of matter clearly reveal to us how many and what they are and how easily we can recognize what they are. Experimental and theoretical exploration for new forms of matter, new quasiparticles, or new electronic and spin states, or new states of photon or properties of light, as well as macroscopic entities with exotic properties represented by the codes of matter, is imminent.

关键词： New materials New electronic state New method Materials design

The Security of Using Large Language Models:A Survey With Emphasis on ChatGPT

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 1-26页

作者： Wei Zhou xiaogang Zhu Qing-Long Han lin Li xiao Chen Sheng Wen Yang Xiang the School of Science Computing and Engineering Technologies Swinburne University of Technology IEEE the School of Computer and Mathematical Sciences the University of Adelaide Adelaide the Faculty of Science and Engineering Southern Cross University the School of Information and Physical Sciences the University of Newcastle

ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential security risks that need to be carefully evaluated and addressed. In this survey, we provide an overview of the current state of research on security of using ChatGPT, with aspects of bias, disinformation, ethics, misuse,attacks and privacy. We review and discuss the literature on these topics and highlight open research questions and future *** this survey, we aim to contribute to the academic discourse on AI security, enriching the understanding of potential risks and mitigations. We anticipate that this survey will be valuable for various stakeholders involved in AI development and usage, including AI researchers, developers, policy makers, and end-users.

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