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基于Google Earth Engine云计算的城市群生态质量长时序动态监测——以粤港澳大湾区为例

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生态学报 2020年第23期40卷 8461-8473页

作者：王渊赵宇豪吴健生北京大学城市规划与设计学院城市人居环境科学与技术重点实验室深圳518055 北京大学城市与环境学院地表过程分析与模拟教育部重点实验室北京100871

人类活动对生态环境的影响日益强烈,及时动态地监测生态现状及其变化信息对城市生态的管理和保护以及可持续发展具有重大意义。遥感生态指数(RSEI)是一种客观、快速和简便的生态质量监测和评价技术,已被广泛应用于生态学研究领域,但在... 详细信息

人类活动对生态环境的影响日益强烈,及时动态地监测生态现状及其变化信息对城市生态的管理和保护以及可持续发展具有重大意义。遥感生态指数(RSEI)是一种客观、快速和简便的生态质量监测和评价技术,已被广泛应用于生态学研究领域,但在进行大范围长时间监测时往往面临云遮挡和拼接困难的问题。因此,本文基于Google Earth Engine(GEE)平台,对1988—2018年来粤港澳大湾区共3530景Landsat遥感影像进行批量去云,采用中值合成法逐年计算绿度、湿度、干度和热度等遥感指标并利用主成分分析法构建遥感生态指数,评价了该区域近30年生态质量的时空变化。该方法改善了遥感生态指数在大范围长时序监测中数据缺失和拼接困难等问题,增加了时间序列的可比性。研究表明:(1)遥感生态指数能够较好地表征粤港澳大湾区的生态质量,其中绿度和湿度指标与其呈正相关,干度和热度指标与其呈负相关;(2)时间上,三十年间粤港澳大湾区生态质量呈"上升-下降-上升-下降"的波动下降趋势,空间上,生态质量具有明显的空间异质性,主要呈现西北和东北部高和中部低的状态。重度和中度退化区主要集中在区域中部,总体改善区域主要位于西部和东北部,基本不变区域主要包括北部区域以及香港,轻度退化区分布较为分散;(3)基于GEE云计算的图像处理可以较好的改善遥感数据缺失、色差和时间不一致等问题,极大的提高影像处理的效率,扩展了遥感生态指数在大范围长时间序列生态监测中的应用。研究结果可以为提升遥感生态指数适用范围和准确度提供参考,并为快速城市化背景下生态保护和土地管理提供理论依据。

关键词：遥感生态指数 Google Earth Engine 生态质量粤港澳大湾区

Radial distribution of magnetic field in earth magnetotail current sheet

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Radial distribution of magnetic field in earth magnetotail c...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Z.J.Rong W.X.Wan C.shen A.A.Petrukovich W.Baumjohann M.W.Dunlop Y.C.Zhang key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences beijing National Observatory of space Environment Institute of Geology and GeophysicsChinese Academy of Sciences state key laboratory of space weather Center for Space Science and Applied ResearchChinese Academy of Sciences

Knowing the magnetic field distribution in the magnetotail current sheet(CS) is essential for exploring magnetotail *** this study,using a joint dataset of Cluster/TC-1,the radial profile of the magnetic field in the magnetotail CS with radial distances covering 820R under different geomagnetic activity states(i.e.,AE≤100 nT for quiet intervals while AE > 100 nT for active times)and solar wind parameters are statistically *** new findings demonstrate that,independent of the activity state,the field strength and B component(GSM coordinates) start the monotonic increase prominently as r decreases down to 1.5R,which means the dipole field starts to make a significant contribution from *** least in the surveyed radial range,the B component is found to be weaker in the midnight and dusk sectors than that in the dawn sector,displaying a dawn-dusk *** occurrence rate of negative B in active times also exhibits a similar asymmetric distribution,which implies active dynamics may occur more frequently at midnight and dusk *** comparison with that in quiet intervals,several features can be seen in active times:(1) a local B minimum between10.512.5R is found in the dusk region,(2) the B component around the midnight region is generally stronger and experiences larger fluctuations,and(3) a sharp positive/negative-excursion of the B component occurs at the dawn/dusk flank regions inside r 5 nPa),which may support the dawn-dusk squeezing effect as presented by Miyashita et al.(2010).The CS B is generally correlated with the interplanetary magnetic field(IMF) B component,and the correlation quality is found to be better with higher penetration coefficient(the ratio of CS B to IMF B) when IMF B is *** implications of the present results are discussed.

关键词： Magnetotail Magnetic structure Current sheet

Electron-ion collider in china

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Frontiers of physics 2021年第6期16卷 1-78页

作者： Daniele PAnderle Valerio Bertone Xu Cao Lei Chang Ningbo Chang Gu Chen Xurong Chen Zhuojun Chen Zhufang Cui Lingyun Dai Weitian Deng Minghui Ding Xu Feng Chang Gong Longcheng Gui Feng-Kun Guo Chengdong Han Jun He Tie-Jiun Hou Hongxia Huang Yin Huang KrešImir KumeričKi LPKaptari Demin Li Hengne Li Minxiang Li Xueqian Li Yutie Liang Zuotang Liang Chen Liu Chuan Liu Guoming Liu Jie Liu Liuming Liu Xiang Liu Tianbo Liu Xiaofeng Luo Zhun Lyu Boqiang Ma Fu Ma Jianping Ma Yugang Ma Lijun Mao Cédric Mezrag HervéMoutarde Jialun Ping Sixue Qin Hang Ren Craig DRoberts Juan Rojo Guodong shen Chao Shi Qintao Song Hao Sun PawełSznajder Enke Wang Fan Wang Qian Wang Rong Wang Ruiru Wang Taofeng Wang Wei Wang Xiaoyu Wang Xiaoyun Wang Jiajun wu Xinggang wu Lei Xia Bowen Xiao Guoqing Xiao Ju-Jun Xie Yaping Xie Hongxi Xing Hushan Xu Nu Xu Shusheng Xu Mengshi Yan Wenbiao Yan Wencheng Yan Xinhu Yan Jiancheng Yang Yi-Bo Yang Zhi Yang Deliang Yao Zhihong Ye Peilin Yin C-PYuan Wenlong Zhan Jianhui Zhang Jinlong Zhang Pengming Zhang Yifei Zhang Chao-Hsi Chang Zhenyu Zhang Hongwei Zhao Kuang-Ta Chao Qiang Zhao Yuxiang Zhao Zhengguo Zhao Liang Zheng Jian Zhou Xiang Zhou Xiaorong Zhou Bingsong Zou Liping Zou Guangdong Provincial key laboratory of Nuclear science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China IRFU CEAUniversitéParis-SaclayF-91191 Gif-sur-YvetteFrance Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of chinese academy of sciences Beijing 100049China Nankai University Tianjin 300071China Xinyang Normal University Xinyang 464000China School of Physics and Materials science Guangzhou UniversityGuangzhou 510006China Hunan University Changsha 410082China Nanjing University Nanjing 210093China Huazhong University of science and Technology Wuhan 430074China European Centre for Theoretical Studies in Nuclear Physics and Related Areas(ECT*)and Fondazione Bruno Kessler Villa TambosiStrada delle Tabarelle 286I-38123 Villazzano(TN)Italy School of Physics Peking UniversityBeijing 100871China Hunan Normal University Changsha 410081China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Nanjing Normal University Nanjing 210023China Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Southwest Jiaotong University Chengdu 610000China Department of Physics Faculty of ScienceUniversity of ZagrebBijenička c.3210000 ZagrebCroatia Bogoliubov laboratory of Theoretical Physics Joint Institute for Nuclear ResearchDubna 141980Russia School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Lanzhou University Lanzhou 730000China key laboratory of Particle Physics and Particle Irradiation(MOE) Shandong UniversityQingdao 266237China key laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China School of Physics Southeast UniversityNanjing 211189China key laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Institute of applied Physics Chinese Academy of SciencesShanghai 201800China Depa

Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as *** a future high energy nuclear physics project,an Electron-ion collider in china(EicC)has been *** will be constructed based on an upgraded heavy-ion accelerator,High Intensity heavy-ion Accelerator Facility(HIAF)which is currently under construction,together with a new electron *** proposed collider will provide highly polarized electrons(with a po-larization of 80%)and protons(with a polarization of 70%)with variable center of mass energies from 15 to 20 GeV and the luminosity of(2–3)×1033 cm^(−2)·s^(−1).Polarized deuterons and Helium-3,as well as unpolarized ion beams from Carbon to Uranium,will be also available at the *** main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region,including 3D tomography of nucleon;the partonic structure of nuclei and the parton interaction with the nuclear environment;the exotic states,especially those with heavy flavor quark *** addition,issues fundamental to understanding the origin of mass could be addressed by measurements of heavy quarkonia near-threshold production at the *** order to achieve the above-mentioned physics goals,a hermetical detector system will be constructed with cutting-edge *** document is the result of collective contributions and valuable inputs from experts across the *** EicC physics program complements the ongoing scientific programs at the Jefferson laboratory and the future EIC project in the United *** success of this project will also advance both nuclear and particle physics as well as accelerator and detector technology in china.

关键词： electron ion collider nucleon structure nucleon mass exotic hadronic states quantum chromodynamics 3D-tomography helicity transverse momentum dependent parton distribution generalized parton distribution energy recovery linac polarization spin rotator

Time delay of interplanetary magnetic field penetration into Earth's magnetotail

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Time delay of interplanetary magnetic field penetration into...

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Z.J.Rong A.T.Y.Lui W.X.Wan Y.Y.Yang C.shen A.A.Petrukovich Y.C.Zhang T.L.Zhang Y.Wei key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences beijing National Observatory of space Environment Institute of Geology and GeophysicsChinese Academy of Sciences Swedish Institute of space Physics applied Physics laboratory Johns Hopkins University state key laboratory of space weather Center for Space Science and Applied ResearchChinese Academy of Sciences space research Institute Russian Academy of Sciences space research Institute Austrian Academy of Sciences

Many previous studies have demonstrated that the interplanetary magnetic field(IMF) can control the magnetospheric *** magnetospheric responses to the external IMF have been assumed for a long *** specific processes by which IMF penetrates into magnetosphere,however,are actually *** this issue will help to accurately interpret the time sequence of magnetospheric activities(e.g.,substorm and tail plasmoids) exerted by *** two carefully selected cases,we found that the penetration of IMF into magnetotail is actually delayed by 1–1.5 h,which significantly lags behind the magnetotail response to the solar wind dynamic *** delayed time appears to vary with different auroral convection intensity,which may suggest that IMF penetration in the magnetotail is controlled considerably by the dayside *** unfavorable cases demonstrate that the penetration lag time is more clearly identified when storm/substorm activities are not involved.

关键词： The penetration of IMF into magnetotail is delayed by 1–1.5 h The delay time strongly depends on the polar convection intensity The penetration efficiency is higher than that reported previously

Method for inferring the axis orientation of cylindrical magnetic flux rope based on single-point measurement

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Method for inferring the axis orientation of cylindrical mag...

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： Z.J.Rong W.X.Wan C.shen T.L.Zhang A.T.Y.Lui Yuming Wang M.W.Dunlop Y.C.Zhang Q.-G.Zong CAS key laboratory of Ionospheric Environment Institute of Geology and GeophysicsChinese Academy of Sciences beijing National Observatory of space Environment Institute of Geology and GeophysicsChinese Academy of Sciences state key laboratory of space weather Center for Space Science and Applied ResearchChinese Academy of Sciences key laboratory of Basic Plasma Physics Department of Geophysics and Planetary SciencesUniversity of Science and Technology of China space research Institute Austrian Academy of SciencesGrazAustria applied Physics laboratory Johns Hopkins UniversityLaurelMarylandUSA. Rutherford Appleton laboratory ChiltonDIDCOTOxfordshireUK Department of Geophysics Peking University

[1]We develop a new simple method for inferring the orientation of a magnetic flux rope,which is assumed to be a time-independent cylindrically symmetric structure via the direct single-point analysis of magnetic field *** model tests demonstrate that, for the cylindrical flux rope regardless of whether it is force-free or not,the method can consistently yield the axis orientation of the flux rope with higher accuracy and stability than the minimum variance analysis of the magnetic field and the Grad-Shafranov reconstruction ***,the radial distance to the axis center and the current density can also be estimated *** to two actual flux transfer events observed by the four satellites of the Cluster mission demonstrates that the method is more appropriate to be

关键词：

霞石NaAlSiO_4的压缩性及其机理研究

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矿物岩石地球化学通报 2017年第5期36卷 850-854页

作者：牛菁菁巫翔秦善翟双猛杨科北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室北京100871 中国科学院地球化学研究所贵阳550002 中国科学院上海应用物理研究所上海201204

NaAlSiO_4高压相CF相的结构和性质近年来被广为关注,然而对其低压相霞石的高压行为研究并不深入。为进一步认识碱金属在CF相中的赋存状态,采用金刚石压腔和同步辐射X射线衍射,开展了霞石NaAlSiO_4(P63,Z=8)常温、20GPa时的压缩性质研究... 详细信息

NaAlSiO_4高压相CF相的结构和性质近年来被广为关注,然而对其低压相霞石的高压行为研究并不深入。为进一步认识碱金属在CF相中的赋存状态,采用金刚石压腔和同步辐射X射线衍射,开展了霞石NaAlSiO_4(P63,Z=8)常温、20GPa时的压缩性质研究。结果显示,在实验压力范围内,霞石没有发生结构相变,其三阶等温状态方程参数为:V0=0.715(2)nm^3,K0=53(3)GPa,K'=4.1(3),a和c轴的压缩系数Ka=3.8(1)×10^(-3)nm/GPa,Kc=2.42(6)×10^(-3)nm/GPa。通过第一性原理计算模拟,印证了实验压缩性的结果,揭示了霞石的压缩机制,即SiO_4和AlO_4四面体呈刚性行为,这些四面体之间的扭转导致结构中伪正交空隙通道的畸变。

关键词：霞石NaAlSiO4 压缩性金刚石压腔 X射线衍射第一性原理计算

Mapping essential urban land use categories in china(EULUC-china):preliminary results for 2018

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science Bulletin 2020年第3期65卷 182-187页

作者： Peng Gong Bin Chen Xuecao Li Han Liu Jie Wang Yuqi Bai Jingming Chen Xi Chen Lei fang Shuailong Feng Yongjiu Feng Yali Gong Hao Gu Huabing Huang Xiaochun Huang Hongzan Jiao Yingdong Kang Guangbin Lei Ainong Li Xiaoting Li Xun Li Yuechen Li Zhilin Li Zhongde Li Chong Liu Chunxia Liu Maochou Liu Shuguang Liu Wanliu Mao Changhong Miao Hao Ni Qisheng Pan Shuhua Qi Zhehao Ren Zhuoran Shan Shaoqing shen Minjun Shi Yimeng Song Mo Su Hoi Ping Suen Bo Sun fangdi Sun Jian Sun Lin Sun Wenyao Sun Tian Tian Xiaohua Tong Yihsing Tseng Ying Tu Hong Wang Lan Wang Xi Wan Zongming Wang Tinghai wu Yaowen Xie Jian Yang Jun Yang Man Yuan Wenze Yue Hongda Zeng Kuo Zhang Neng Zhang Tao Zhang Yu Zhang Feng Zhao Yichen Zheng Qiming Zhou Nicholas Clinton Zhiliang Zhu Bing Xu Ministry of Education key laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084China Tsinghua Urban Institute Tsinghua UniversityBeijing 100084China center for Healthy Cities Institute for China Sustainable UrbanizationTsinghua UniversityBeijing 100084China Department of Land Air and Water ResourcesUniversity of CaliforniaDavisCA 95616-8627USA Department of Geological and Atmospheric sciences Iowa State UniversityAmesIA 50011USA state key laboratory of Remote Sensing science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101China AI for Earth laboratory Cross-Strait InstituteTsinghua UniversityBeijing 100084China International Institute for Earth System sciences Nanjing UniversityNanjing 210093China research center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumchi 830011China key laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China National Engineering laboratory for applied Technology in Forestry&Ecology in South china College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha 410004China College of Surveying&Geo-Informatics Tongji UniversityShanghai 200092China Department of Urban Planning College of Architecture and Urban PlanningTongji UniversityShanghai 200092China beijing Institute of Urban Planning Beijing 100045China Department of Urban Planning School of Urban DesignWuhan UniversityWuhan 430072China College of Earth sciences Jilin UniversityChangchun 130061China research center for Digital Mountain and Remote Sensing Application Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Institute of Remote Sensing and Geographic Information System School of Earth and Space SciencesPeking UniversityBeijing 100871China Department of Urban and Regional Planning School of Geography and PlanningSun Yat-sen Univ

Land use reflects human activities on *** land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and *** areas have widespread effects on local hydrology,climate,biodiversity,and food production[1,2].However,maps,that contain knowledge on the distribution,pattern and composition of various land use types in urban areas,are limited to city *** mapping standard on data sources,methods,land use classification schemes varies from city to city,due to differences in financial input and skills of mapping *** address various national and global environmental challenges caused by urbanization,it is important to have urban land uses at the national and global scales that are derived from the same or consistent data sources with the same or compatible classification systems and mapping *** is because,only with urban land use maps produced with similar criteria,consistent environmental policies can be made,and action efforts can be compared and assessed for large scale environmental ***,despite of the fact that a number of urban-extent maps exist at global scales[3,4],more detailed urban land use maps do not exist at the same *** at big country or regional levels such as for the United states,china and European Union,consistent land use mapping efforts are rare[5,6](e.g.,https://***/open_land_use/).

关键词： EULUC-china 土地利用类型

Profile of strong magnetic field By component in magnetotail current sheets

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Profile of strong magnetic field By component in magnetotail...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Z.J.Rong W.X.Wan C.shen X.Li M.W.Dunlop A.A.Petrukovich L.-N.Hau T.L.Zhang H.Reme A.M.Du E.Lucek beijing National Observatory of space Environment Institute of Geology and GeophysicsChinese Academy of Sciences state key laboratory of space weather Center for Space Science and Applied ResearchChinese Academy of Sciences laboratory for Atmosphere and space Physics Department of Aerospace and Engineering SciencesUniversity of Colorado at BoulderBoulderColoradoUSA. Rutherford Appleton laboratory OxfordUK. space research Institute MoscowRussia. Institute of space science National Central UniversityJhongliTaiwan. Department of Geophysics and Planetary sciences University of Science and Technology of ChinaHefeiChina space research Institute Austrian Academy of SciencesGrazAustria. IRAP University of ToulouseToulouseFrance.CNRSIRAPToulouseFrance. Blackett laboratory Imperial College LondonLondonUK.

[1]The strong magnetic field B component(in GSM coordinates) has been increasingly noticed to play an important role in the dynamics of tail current sheet (CS).The distribution profile of strong B components in the ta...

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Chiral Dirac Fermion in a Collinear Antiferromagnet

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chinese Physics Letters 2023年第12期40卷 84-91页

作者：张奥邓可盛洁明刘鹏飞 Shiv Kumar Kenya Shimada 江志诚刘正太沈大伟李嘉裕任俊王乐周良 Yoshihisa Ishikawa Takashi Ohhara Qiang Zhang Garry McIntyre Dehong Yu 刘恩克吴留锁陈朝宇刘奇航 shenzhen Institute for Quantum science and Technology and Department of Physics Southern University of Science and TechnologyShenzhen 518055China academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Hiroshima Synchrotron Radiation Centre Hiroshima UniversityHigashi-HiroshimaHiroshima 739-0046Japan state key laboratory of Functional Materials for Informatics and center for Excellence in Superconducting Electronics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Neutron science and Technology center Comprehensive Research Organization for Science and SocietyTokaiIbaraki 319-1106Japan Neutron science Section J-PARC CenterJapan Atomic Energy AgencyIbaraki 319-1195Japan Neutron science Division Oak Ridge National LaboratoryOak RidgeTennessee 37831USA Australian Nuclear science and Technology Organisation Locked bag 2001Kirrawee DCNew South Wales 2232Australia state key laboratory for Magnetism Institute of PhysicsChinese Academy of SciencesBeijing 100190China

In a Dirac semimetal, the massless Dirac fermion has zero chirality, leading to surface states connected adiabatically to a topologically trivial surface state as well as vanishing anomalous Hall effect. Recently, it is predicted that in the nonrelativistic limit of certain collinear antiferromagnets, there exists a type of chiral“Dirac-like” fermion, whose dispersion manifests four-fold degenerate crossing points formed by spin-degenerate linear bands, with topologically protected Fermi arcs. Such an unconventional chiral fermion, protected by a hidden SU(2) symmetry in the hierarchy of an enhanced crystallographic group, namely spin space group, is not experimentally verified yet. Here, by angle-resolved photoemission spectroscopy measurements, we reveal the surface origin of the electron pocket at the Fermi surface in collinear antiferromagnet CoNb3S6. Combining with neutron diffraction and first-principles calculations, we suggest a multidomain collinear antiferromagnetic configuration, rendering the the existence of the Fermi-arc surface states induced by chiral Dirac-like *** work provides spectral evidence of the chiral Dirac-like fermion caused by particular spin symmetry in CoNb_(3)S_(6), paving an avenue for exploring new emergent phenomena in antiferromagnets with unconventional quasiparticle excitations.

关键词： Fermi Dirac chiral