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全球海洋偶极子涡旋特征提取与动力调制的遥感研究

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遥感学报 2023年第4期27卷 932-942页

作者：禹乐乐曹川川王璇陈戈中国海洋大学信息科学与工程学部海洋技术学院青岛266100 青岛海洋科学与技术试点国家实验室青岛266237 潍坊学院物理与光电工程学院潍坊261061

中尺度涡旋具有封闭的环流结构,在海洋物质输运与能量平衡方面发挥了重要作用。观测表明海洋中涡旋并非是孤立的:气旋涡与反气旋涡倾向于相互伴随而形成稳定传播的偶极子结构。本文以1993年—2020年卫星高度计识别与追踪的中尺度涡旋数... 详细信息

中尺度涡旋具有封闭的环流结构,在海洋物质输运与能量平衡方面发挥了重要作用。观测表明海洋中涡旋并非是孤立的:气旋涡与反气旋涡倾向于相互伴随而形成稳定传播的偶极子结构。本文以1993年—2020年卫星高度计识别与追踪的中尺度涡旋数据为基础,结合涡旋的时空特征提出了偶极子涡旋的判据,建立偶极子涡旋数据集。结果表明偶极子涡旋主要分布于南北纬10°—70°纬度范围内,且平均占比约为29.53%。偶极子结构的形成对涡旋有明显的调制作用,相对于非偶极子状态,偶极子状态的涡旋振幅的增强幅度为11.09%、半径的增强幅度为7.33%、动能的增强幅度为8.58%,涡旋涡度的减小幅度为1.34%。同时,调制作用与涡旋所处的纬度和生命状态有关。在运动特征方面,偶极子状态下涡旋的传播稍有增速,变化在10%以内,而平均地转流速的最大增幅超过30%,其高值对应海洋的强流区。全球偶极子涡旋的定量分析将有助于深化对涡旋动力学的理解,为进一步剖析涡—涡相互作用机理与精细化海洋数值模拟奠定基础。

关键词：遥感卫星高度计中尺度涡旋偶极子涡旋参数统计调制作用

The validation of the significant wave height product of HY-2altimeter–primary results

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Acta Oceanologica Sinica 2013年第11期32卷 82-86页

作者： chen Chuntao ZHU Jianhua LIN Mingsen ZHAO Yili HUANG Xiaoqi WANG He ZHANG Youguang PENG Hailong National Ocean Technology Center State Oceanic Administration National Satellite Ocean Application Service of State Oceanic Administration State Oceanic Administration

The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height （SWH） is validated by the data from the South China Sea （SCS） field experiment, National Data Buoy Center （NDBC/ buoys and jason-1/2 altimeters, and is corrected using a linear regression with in-situ measurements. Com- pared with NDBC SWH, the HY-2 SWH show a RMS of 0.36 m, which is similar to jason- 1 and jason-2 SWH with the RMS of 0.35 m and 0.37 m respectively; the RMS of corrected HY-2 SWH is 0.27 m, similar to 0.27 m and 0.23 m of corrected jason-1 and jason-2 SWH. Therefore the accuracy of HY-2 SWH products is close to that of jason-1/2 SWH, and the linear regression function derived can improve the accuracy of HY-2 SWH products.

关键词： altimeter significant wave height validation linear regression correction root mean square

Crowdsourcing in health and medical research:a systematic review

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Infectious Diseases of Poverty 2020年第1期9卷 96-96页

作者： cheng Wang Larry Han Gabriella Stein Suzanne Day Cedric Bien-Gund Allison Mathews jason JOng Pei-Zhen Zhao Shu-Fang Wei Jennifer Walker Roger Chou Amy Lee Angela chen Barry Bayus Joseph D.Tucker 不详 Social Entrepreneurship to Spur Health GuangzhouChina Institute of Global Health and Infectious Diseases University of North Carolina at Chapel HillChapel HillUSA

Background:Crowdsourcing is used increasingly in health and medical *** is the process of aggregating crowd wisdom to solve a *** purpose of this systematic review is to summarize quantitative evidence on crowdsourcing to improve ***:We followed Cochrane systematic review guidance and systematically searched seven databases up to September 4th *** were included if they reported on crowdsourcing and related to health or *** were excluded if recruitment was the only use of *** determined the level of evidence associated with review findings using the GRADE ***:We screened 3508 citations,accessed 362 articles,and included 188 ***-six studies examined effectiveness,127 examined feasibility,and 37 examined *** most common purposes were to evaluate surgical skills(17 studies),to create sexual health messages(seven studies),and to provide layperson cardiopulmonary resuscitation(CPR)out-of-hospital(six studies).Seventeen observational studies used crowdsourcing to evaluate surgical skills,finding that crowdsourcing evaluation was as effective as expert evaluation(low quality).Four studies used a challenge contest to solicit human immunodeficiency virus(HIV)testing promotion materials and increase HIV testing rates(moderate quality),and two of the four studies found this approach saved *** studies suggested that an interactive technology system increased rates of layperson initiated CPR out-ofhospital(moderate quality).However,studies analyzing crowdsourcing to evaluate surgical skills and laypersoninitiated CPR were only from high-income *** studies examined crowdsourcing to inform artificial intelligence projects,most often related to annotation of medical *** was evaluated using different outcomes,limiting the extent to which studies could be ***:Crowdsourcing has been used to improve health in many *** crowds

关键词： Crowdsourcing Innovation Challenge contest Systematic review Medicine Health

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3G网络下移动学习的探索与实践

开放教育研究 2012年第1期18卷 159-162页

作者：郑洁琼陈泽宇王敏娟杰森.吴上海交通大学现代远程教育研究中心上海200030 圣地亚哥州立大学阿联酋电信和英国电信联合创新中心

近年来,基于移动通信技术和移动互联网技术的移动学习已经成为现代远程教育中一种新型的学习方式,它不仅具有传统远程教育的优势,还兼备高度的移动性、交互性、个性化等特点,进一步实现了人们"随时、随地、随身"的学习愿望。3G技术的推... 详细信息

近年来,基于移动通信技术和移动互联网技术的移动学习已经成为现代远程教育中一种新型的学习方式,它不仅具有传统远程教育的优势,还兼备高度的移动性、交互性、个性化等特点,进一步实现了人们"随时、随地、随身"的学习愿望。3G技术的推出,使得在移动学习中高速传递学习资源成为可能,这成为人们关注的又一热点。本文以上海交通大学数字化学习实验室(E-Learning Lab)研发的移动学习网站为研究平台,开发了对应的手机客户端。通过Webservice服务实现网站与手机客户端之间的数据通信,用户在移动学习中若有问题,可直接编辑短信发送到指定号码,后台答疑库会自动回复相关答案,实现了移动学习的高度移动性、交互性等特点。研究者还做了性能和用户体验测试,各方面指标都达到要求,并能提供良好的用户体验。

关键词：远程教育移动学习第三代移动通信技术 Webservice

A robust soc-MOF platform exhibiting high gravimetric uptake and volumetric deliverable capacity for on-board methane storage

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Nano Research 2021年第2期14卷 512-517页

作者： Gaurav Verma Sanjay Kumar Harsh Vardhan Junyu Ren Zheng Niu Tony Pham Lukasz Wojtas Sydney Butikofer Jose C Echeverria Garcia Yu-Sheng chen Brian Space and Shengqian Ma Department of Chemistry University of South Florida4202 E.Fowler Ave.TampaFL 33637USA ChemMatCARS Center for Advanced Radiation SourcesThe University of Chicago9700 South Cass AvenueArgonneIL 60439USA Department of Chemistry Multani Mai Modi CollegePatiala 147001India Department of Chemistry Biochemistryand PhysicsThe University of Tampa401 W.Kennedy Blvd.TampaFL 33606-1490USA Department of Chemical and Biomolecular Engineering University of Illinois at Urbana-ChampaignChampaignIL 61801USA

Emerging as an outperformed class of metal-organic frameworks(MOFs),square-octahedron(soc)topology MOFs(soc-MOFs)feature superior properties of high porosity,large gas storage capacity,and excellent thermal/chemical *** report here an iron based soc-MOF,denoted as Fe-pbpta(H4pbpta=4,4',4'',4'''-(1,4-phenylenbis(pyridine-4,2-6-triyl))-tetrabenzoic acid)possessing a very high Brunauer,Emmett and Teller(BET)surface area of 4,937 m2/g and a large pore volume of 2.15 cm3/*** MOF demonstrates by far the highest gravimetric uptake of 369 cm3(STP)/g under the DOE operational storage conditions(35 bar and 298 K)and a high volumetric deliverable capacity of 192 cc/cc at 298 K and 65 ***,Fe-pbpta exhibits high thermal and aqueous stability making it a promising candidate for on-board methane storage.

关键词： metal-organic framework(MOF) reticular chemistry methane storage aqueous stability high gravimetric and volumetric uptake

Development of a fine-resolution atmosphere-wave-ocean coupled forecasting model for the South China Sea and its adjacent seas

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Acta Oceanologica Sinica 2019年第4期38卷 154-166页

作者： Junchuan Sun Zexun Wei Tengfei Xu Meng Sun Kun Liu Yongzeng Yang Li chen Hong Zhao Xunqiang Yin Weizhong Feng Zhiyuan Zhang Yonggang Wang Key Laboratory of Marine Science and Numerical Modeling First Institute of OceanographyMinistry of Natural Resources Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology National Marine Environmental Forecasting Center Ministry of Natural Resources South China Sea Marine Prediction Center Ministry of Natural Resources Hydro-Meteorological Center of Navy PLA

A 72-h fine-resolution atmosphere-wave-ocean coupled forecasting system was developed for the South China Sea and its adjacent seas. The forecasting model domain covers from from 15°S to 45°N in latitude and 99°E to135°E in longitude including the Bohai Sea, the Yellow Sea, the East China Sea, the South China Sea and the Indonesian seas. To get precise initial conditions for the coupled forecasting model, the forecasting system conducts a 24-h hindcast simulation with data assimilation before forecasting. The Ensemble Adjustment Kalman Filter(EAKF) data assimilation method was adopted for the wave model MASNUM with assimilating jason-2 significant wave height(SWH) data. The EAKF data assimilation method was also introduced to the ROMS model with assimilating sea surface temperature(SST), mean absolute dynamic topography(MADT) and Argo profiles data. To improve simulation of the structure of temperature and salinity, the vertical mixing scheme of the ocean model was improved by considering the surface wave induced vertical mixing and internal wave induced vertical mixing. The wave and current models were integrated from January 2014 to October 2015 driven by the ECMWF reanalysis 6 hourly mean dataset with data assimilation. Then the coupled atmosphere-wave-ocean forecasting system was carried out 14 months operational running since November 2015. The forecasting outputs include atmospheric forecast products, wave forecast products and ocean forecast products. A series of observation data are used to evaluate the coupled forecasting results, including the wind, SHW, ocean temperature and *** forecasting results are in good agreement with observation data. The prediction practice for more than one year indicates that the coupled forecasting system performs stably and predict relatively accurate, which can support the shipping safety, the fisheries and the oil exploitation.

关键词： South China Sea COAWST model MASNUM model atmosphere-wave-ocean forecasting system data assimilation

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星载成像高度计双侧独立交叉定标方法

遥感学报 2023年第4期27卷 919-931页

作者：白卓张颢馨马纯永赵朝方陈戈中国海洋大学信息科学与工程学院青岛266100 青岛海洋科学与技术试点国家实验室青岛266237

为通过数据处理提高SWOT的观测精度,本文采用双侧刈幅独立交叉定标对相位误差和倾角误差复合输入的情况进行误差估计。本文选取横跨经度100°和纬度60°的南太平洋东部地区,以HYCOM数据作为海洋真值,根据AVISO官网提供的SWOT和jason-2 (... 详细信息

为通过数据处理提高SWOT的观测精度,本文采用双侧刈幅独立交叉定标对相位误差和倾角误差复合输入的情况进行误差估计。本文选取横跨经度100°和纬度60°的南太平洋东部地区,以HYCOM数据作为海洋真值,根据AVISO官网提供的SWOT和jason-2 (2016年10月前)轨道参数利用SWOT simulator进行仿真采样,进行刈幅自交叉和星下点刈幅交叉实验。实验将90%的误差校正到4 cm内,近75%的交叉点残差的标准差降到2 cm内,较解算前提升一倍,表明在仪器精度较低时,双侧刈幅独立交叉定标的方法能够科学有效估计两种误差的复合输入值,显著降低了误差水平。

关键词：交叉定标误差反演相位误差基线倾角误差干涉成像高度计

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HY-2C卫星海面高度数据的质量分析

海洋学报 2022年第10期44卷 173-181页

作者：孟菊于方杰庄志远齐娟娟陈戈中国海洋大学信息科学与工程学部海洋技术学院山东青岛266100 青岛海洋科学与技术试点国家实验室区域海洋学与数值模拟实验室山东青岛266237

卫星海面高度数据对于监测全球海面高度具有重要的意义,所以卫星高度数据的定标和检验变得至关重要。海洋二号C(HY-2C)卫星是继海洋二号B卫星后的第二颗业务卫星,于2020年成功发射升空。然而,目前对HY-2C卫星高度计的数据质量了解甚少,... 详细信息

卫星海面高度数据对于监测全球海面高度具有重要的意义,所以卫星高度数据的定标和检验变得至关重要。海洋二号C(HY-2C)卫星是继海洋二号B卫星后的第二颗业务卫星,于2020年成功发射升空。然而,目前对HY-2C卫星高度计的数据质量了解甚少,所以对HY-2C卫星的海面高度数据进行质量分析具有重要的意义。本文以同期观测的HY-2B卫星和jason-3卫星的地球物理数据(GDR)为参考,对HY-2C卫星遥感地球物理数据(SGDR)中的海面高度数据进行质量分析。结果显示,在星星交叉定标中使用3种常见的交叉定标插值方法对HY-2C卫星的海面高度异常数据进行自交叉点分析时,HY-2C卫星海面高度异常数据质量分析的结果不同。其中使用三次样条插值方法进行质量分析的结果最优,得到海平面高度异常差的平均值为0.03 cm,标准差为6.17 cm。此外,对HY-2C卫星和HY-2B卫星互交叉点海面高度异常差异的平均值为−0.47 cm,标准差为5.32 cm;HY-2C卫星SGDR与jason-3卫星GDR的海面高度异常数据进行互交叉点分析,得到海平面高度异常差的平均值为−0.3 cm,标准差为5.32 cm,这些数据表明HY-2C卫星的测高精度与HY-2B卫星、jason-3卫星一致。因此HY-2C高度计产品数据质量稳定,能满足海洋应用和科学研究的需要。

关键词： HY-2C卫星高度计海面高度交叉点分析

北部湾海浪季节变化和驱动因素的数值模拟研究

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海洋学报 2022年第10期44卷 10-19页

作者：赵红军王俊达孔俊陈国平河海大学港口海岸与近海工程学院江苏南京210098 河海大学海岸灾害及防护教育部重点实验室江苏南京210098

基于NCEP CFSV2再分析风场驱动SWAN模型,对南海至北部湾为期1年的海浪逐时过程进行了数值模拟,利用jason-2卫星和近岸浮标整年观测数据检验了模拟效果。在此基础上,评估了模型空间网格尺度对北部湾内波浪模拟的影响,分析了波浪的季节变... 详细信息

基于NCEP CFSV2再分析风场驱动SWAN模型,对南海至北部湾为期1年的海浪逐时过程进行了数值模拟,利用jason-2卫星和近岸浮标整年观测数据检验了模拟效果。在此基础上,评估了模型空间网格尺度对北部湾内波浪模拟的影响,分析了波浪的季节变化特征,辨析了局地风和南海传入浪对海湾波浪的驱动贡献。研究显示:(1)较jason-2卫星观测值,有效波高模拟值的均方根误差和分散系数分别约为0.4 m和0.2;较北部湾湾顶近岸浮标逐时观测值,有效波高的均方根误差和分散系数分别约为0.2 m和0.4,平均波周期的均方根误差和分散系数分别约为0.6 s和0.2,平均波向的均方根误差约为30°;(2)空间网格分辨率为12'×12'的模型对北部湾20 m以深开敞海域波浪的模拟效果良好,模拟值较2'×2'模型的平均相对偏差在10%以下;(3)北部湾冬季盛行东北向波,夏季盛行偏南向浪,季风转换期盛行东南向浪,全年波浪在季风期强于季风转换期,冬季最强、冬夏转换期最弱;(4)局地风对北部湾波浪的驱动贡献自湾口向湾内增强,季风期强于季风转换期;南海传入浪的驱动贡献自湾口向湾内减弱,季风转换期强于季风期;海湾中部和北部的波浪以局地风为主控因素,海南岛南部和东部水域以传入浪的影响为主,海南岛西南水域受局地风和传入浪的共同控制。

关键词： CFSV2风场 SWAN 北部湾波浪模拟季节变化驱动因素