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基于WRF和随机森林的臭氧短期预报模型研究——以青岛为例

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环境生态学 2024年第3期6卷 84-92,106页

作者：卢维肖周易杨元建孙爱青方渊孟赫南京信息工程大学大气物理学院江苏南京210044 南京信息工程大学管理工程学院江苏南京210044 华润新能源(睢宁)有限公司江苏徐州221200 山东省青岛生态环境监测中心山东青岛266003

本研究以青岛市为例,基于WRF模式预报与随机森林方法,利用2022年9月9个站点的预报与实况数据进行了气象要素预报的订正,回代气象要素订正数据并加入静态数据建立了O_(3)浓度的短期预报模型,实现了每个站点预报时效为7 d、时间分辨率为1 ... 详细信息

本研究以青岛市为例,基于WRF模式预报与随机森林方法,利用2022年9月9个站点的预报与实况数据进行了气象要素预报的订正,回代气象要素订正数据并加入静态数据建立了O_(3)浓度的短期预报模型,实现了每个站点预报时效为7 d、时间分辨率为1 h的预报,对气象要素订正与O_(3)预报效果进行评估与分析。结果表明,气象要素2 m气温、地面气压、2 m相对湿度、10 m风速均有不同程度的订正,尤其是地面气压与10 m风速订正效果明显;O_(3)浓度预报模型有良好的预报效果,RMSE较WRF预报减少了22.1%,站点预报误差均有改善且大部分效果明显。

关键词：臭氧随机森林预报订正青岛市

Influence of urbanization on the thermal environment of meteorological station:Satellite-observed evidence

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Advances in Climate Change Research 2015年第1期6卷 7-15页

作者： SHI Tao HUANG Yong WANG Hong SHI Chun-E yang yuan-jian Key Laboratory of Atmospheric Sciences and Satellite Remote Sensing of Anhui Province Anhui Institute of Meteorological Sciences Wuhu Meteorological Bureau Nanjing University of Information Science and Technology

In this paper, five national meteorological stations in Anhui province are taken as typical examples to explore the effects of local urbanization on their thermal environment by using Landsat data from 1990 to 2010. Satellite-based land use/land cover(LULC), land surface temperature(LST), normalized difference vegetation index(NDVI) are used to investigate the effects. The study shows that LULC around meteorological stations changed significantly due to urban expansion. Fast urbanization is the main factor that affects the spatial-temporal distribution of thermal environment around meteorological stations. Moreover, the normalized LST and NDVI exhibit strong inverse correlations around meteorological stations, so the variability of LST can be monitored through evaluating the variability of NDVI. In addition, station-relocation plays an important role in improving representativeness of thermal environment. Notably, the environment representativeness was improved, but when using the data from the station to study climate change, the relocation-induced inhomogeneous data should be considered and adjusted. Consequently,controlling the scale and layout of the urban buildings and constructions around meteorological stations is an effective method to ameliorate observational thermal environment and to improve regional representativeness of station observation. The present work provides observational evidences that high resolution Landsat images can be used to evaluate the thermal environment of meteorological stations.

关键词： Urbanization Thermal environment Representativeness Land surface temperature Normalized difference vegetation index (NDVI)

替换或加用齐拉西酮对精神分裂症患者代谢综合征的影响

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临床精神医学杂志 2024年第4期34卷 272-275页

作者：欧阳紫颖杨远坚李逸恒魏波江西省精神病院江西省精神心理疾病临床研究中心330029

目的:探讨换用或加用齐拉西酮对精神分裂症(schizophrenia,SCZ)患者代谢综合征(metabolic syndrome,MetS)的影响。方法:纳入2022年7月至2022年12月在江西省精神病院的60例伴有MetS的精神分裂症患者,分为换用齐拉西酮组(n=30)和联用齐拉... 详细信息

目的:探讨换用或加用齐拉西酮对精神分裂症(schizophrenia,SCZ)患者代谢综合征(metabolic syndrome,MetS)的影响。方法:纳入2022年7月至2022年12月在江西省精神病院的60例伴有MetS的精神分裂症患者,分为换用齐拉西酮组(n=30)和联用齐拉西酮组(n=30)。收集患者的基本情况,并对其换药前以及换药后4周和8周的各项代谢指标进行检测和比较。结果:有48例患者完成研究,换用齐拉西酮组(n=28)的腰围(F=5.635,P=0.0165),三酰甘油(F=7.944,P=0.0069),收缩压(F=6.227,P=0.0107)和舒张压(F=4.960,P=0.0210)明显降低,高密度脂蛋白明显升高(F=3.406,P=0.0405)。联用齐拉西酮组(n=20)的腰围(F=21.58,P<0.0001)和收缩压(F=4.396,P=0.0318)明显降低。这些代谢指标在换用组和联用组之间以及不同剂量齐拉西酮之间差异均无统计学意义。结论:换用或联用齐拉西酮可作为临床处理SCZ患者出现MetS不良反应的一种可行方案。

关键词：精神分裂症代谢综合征齐拉西酮

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PRESSURE DISTRIBUTION ON THE WALL OF THE INNER CYLINDER RECIPROCATING AXIALLY TO THE UNSTEADY FLOW OF VISCOELASTIC FLUID IN ECCENTRIC ANNULUS

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Journal of Hydrodynamics 2006年第5期18卷 606-612页

作者： WANG Yan CUI Hai-qing yang yuan-jian GUO Jun-hui LI Nan Department of Petroleum Engineering China University of Petroleum Beijing 102249 China Department of Petroleum Engineering Daqing Petroleum Institute Daqing 163318 China

In this article, the governing equations for the unsteady flow of viscoelastic fluid in the eccentric annulus with the inner cylinder reciprocating axially and the expression of the pressure distribution on the wall of the inner cylinder of the annulus are established and derived, respectively, under the bipolar coordinate system. The equations and the expression are solved and calculated numerically using the finite difference method, respectively. The curves of the pressure distribution on the wall of the inner cylinder of the aqueous solution of Hydrolyzed Polyacrylamide （HPAM） are plotted and the influences of annular eccentricity, stroke, and stroke frequency on the pressure distribution are analyzed.

关键词： viscoelastic unsteady flow eccentric annulus fluid reciprocating axially pressure distribution

Summer Monsoon Impacts on Chlorophyll-a Concentration in the Middle of the South China Sea:Climatological Mean and Annual Variability

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Atmospheric and Oceanic Science Letters 2012年第1期5卷 15-19页

作者： yang yuan-jian XIAN Tao SUN Liang FU Yun-Fei Key Laboratory of Atmospheric Sciences and Satellite Remote Sensing of Anhui Province Anhui Institute of Meteorological Sciences Hefei 230031 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics （LASG） Institute of Atnospheric Physics Chinese Academy of Sciences Beijing 100029 China Laboratory of Atmospheric Observation and Climatological Environment School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

Climatological mean and annual variations of Chlorophyll-a （Chl-a） distribution, sea surface wind （SSW）, and sea surface temperature （SST） from 1998 to 2008 were analyzed in the middle of the South China Sea （SCS）, focusing on the typical region off the east coast of Vietnam （8.5-14°N, 109.5-114°E）. Based on remote sensing data and SCS summer monsoon index （SCSSMI） data, high Chl-a concentrations in the middle of the SCS in the southwest summer monsoon season （June-September） may be related to strong Ekman pumping and strong wind stress. The maximum of the monthly averaged cli- matological Chl-a in the summer appeared in August. According to the annual variation, there was a significant negative correlation （r = -0.42） between the SCSSMI and SST, a strongly positive correlation （r=0.61） between the SCSSMI and Chl-a, and a strongly negative correlation （r = -0.74） between the SST and Chl-a in the typical region off the east coast of Vietnam during 1998-2008. Due to the E1 Nifio event specifically, the phenomena of a low Chl-a concentration, high SST and weak SCSSMI were extremely predominant in the summer of 1998. These relationships imply that the SCSSMI associated with the SST could be used to predict the annual variability of summer Chl-a in the SCS.

关键词： Chlorophyll-a monsoon South China Sea annual variability

The Caching and Pricing Strategy for Information-Centric Networking with Advertisers’Participation

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China Communications 2024年第3期21卷 283-295页

作者： Zheng Quan Yan Wenliang Wu Rong Tan Xiaobin yang jian yuan Liu Xu Zhenghuan Laboratory for Future Networks Department of AutomationUniversity of Science and Technology of ChinaHefei 230026China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230088China Suzhou Nuclear Power Research Institute Suzhou 215004China National Engineering Laboratory for Public Safety Risk Perception and Control by Big Data(NEL-PSRPC) China Academy of Electronics and Information Technology of CETCBeijing 100041China

As users’access to the network has evolved into the acquisition of mass contents instead of IP addresses,the IP network architecture based on end-to-end communication cannot meet users’***,the Information-Centric Networking(ICN)came into *** a technical point of view,ICN is a promising future network *** and customizing a reasonable pricing mechanism plays a positive role in promoting the deployment of *** current research on ICN pricing mechanism is focused on paid ***,we study an ICN pricing model for free content,which uses game theory based on Nash equilibrium to *** this work,advertisers are considered,and an advertiser model is established to describe the economic interaction between advertisers and ICN *** solution can formulate the best pricing strategy for all ICN entities and maximize the benefits of each *** extensive analysis and numerical results show that the proposed pricing framework is significantly better than existing solutions when it comes to free content.

关键词： advertisers cache free content Information-Centric Networking pricing strategy

Assessment of the three representative empirical models for zenith tropospheric delay(ZTD)using the CMONOC data

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Geodesy and Geodynamics 2024年第5期15卷 488-494页

作者： Debao yuan jian Li Yifan Yao Fei yang Yingying Wang Ran Chen Tairan Xu College of Geoscience and Surveying Engineering China University of Mining and Technology-BeijingBeijing100083China Hubei Luojia Laboratory Wuhan430079China

The precise correction of atmospheric zenith tropospheric delay(ZTD)is significant for the Global Navigation Satellite System(GNSS)performance regarding positioning accuracy and convergence *** the past decades,many empirical ZTD models based on whether the gridded or scattered ZTD products have been proposed and widely used in the GNSS positioning *** there is no comprehensive evaluation of these models for the whole China region,which features complicated topography and *** this study,we completely assess the typical empirical models,the IGGtropSH model(gridded,non-meteorology),the SHAtropE model(scattered,non-meteorology),and the GPT3 model(gridded,meteorology)using the Crustal Movement Observation Network of China(CMONOC)*** general,the results show that the three models share consistent performance with RMSE/bias of 37.45/1.63,37.13/2.20,and 38.27/1.34 mm for the GPT3,SHAtropE and IGGtropSH model,***,the models had a distinct performance regarding geographical distribution,elevation,seasonal variations,and daily *** the southeastern region of China,RMSE values are around 50 mm,which are much higher than that in the western region,approximately 20 *** SHAtropE model exhibits better performance for areas with large variations in *** GPT3 model and the IGGtropSH model are more stable across different months,and the SHAtropE model based on the GNSS data exhibits superior performance across various UTC epochs.

关键词： GNSS Zenith tropospheric delay Empirical ZTD model CMONOC data

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： Yong yang Ren-Sheng CHEN Yong-jian DING Hong-yuan LI Zhang-Wen LIU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming

Global Spherically Symmetric Solutions for a Coupled Compressible Navier–Stokes/Allen–Cahn System

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2037-2064页

作者： Chang Ming SONG jian Lin ZHANG yuan yuan WANG Department of Applied Mathematics School of Mathematics and Information ScienceZhongyuan University of TechnologyZhengzhou 450007P.R.China

In this paper,we consider the global spherically symmetric solutions for the initial boundary value problem of a coupled compressible Navier–Stokes/Allen–Cahn system which describes the motion of two-phase viscous compressible *** prove the existence and uniqueness of global classical solution,weak solution and strong solution under the assumption of spherically symmetry condition for initial dataρ0 without vacuum state.

关键词： Diffuse interface model global solutions Navier-Stokes equations Allen-Cahn equation spherically symmetry