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Comparison of PM_(2.5) and CO_(2) Concentrations in Large Cities of China during the COVID-19 Lockdown 被引量:4
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作者 chuwei liu Zhongwei HUANG +6 位作者 Jianping HUANG Chunsheng LIANG Lei DING Xinbo LIAN Xiaoyue liu Li Zhang Danfeng WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第6期861-875,共15页
Estimating the impacts on PM_(2.5)pollution and CO_(2)emissions by human activities in different urban regions is important for developing efficient policies.In early 2020,China implemented a lockdown policy to contai... Estimating the impacts on PM_(2.5)pollution and CO_(2)emissions by human activities in different urban regions is important for developing efficient policies.In early 2020,China implemented a lockdown policy to contain the spread of COVID-19,resulting in a significant reduction of human activities.This event presents a convenient opportunity to study the impact of human activities in the transportation and industrial sectors on air pollution.Here,we investigate the variations in air quality attributed to the COVID-19 lockdown policy in the megacities of China by combining in-situ environmental and meteorological datasets,the Suomi-NPP/VIIRS and the CO_(2)emissions from the Carbon Monitor project.Our study shows that PM_(2.5)concentrations in the spring of 2020 decreased by 41.87%in the Yangtze River Delta(YRD)and 43.30%in the Pearl River Delta(PRD),respectively,owing to the significant shutdown of traffic and manufacturing industries.However,PM_(2.5)concentrations in the Beijing-Tianjin-Hebei(BTH)region only decreased by 2.01%because the energy and steel industries were not fully paused.In addition,unfavorable weather conditions contributed to further increases in the PM_(2.5)concentration.Furthermore,CO_(2)concentrations were not significantly affected in China during the short-term emission reduction,despite a 19.52%reduction in CO_(2)emissions compared to the same period in 2019.Our results suggest that concerted efforts from different emission sectors and effective long-term emission reduction strategies are necessary to control air pollution and CO_(2)emissions. 展开更多
关键词 PM_(2.5) CO_(2)emissions lockdown measures traffic emission industrial activity
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基于集合经验模态分解和自回归-移动平均模型的COVID-19流行病全球预测系统预测结果改进 被引量:5
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作者 chuwei liu Jianping Huang +4 位作者 Fei Ji Li Zhang Xiaoyue liu Yun Wei Xinbo Lian 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第4期52-57,共6页
2020年,新型冠状病毒肺炎(COVID-19)在世界范围内迅速传播.为准确预测各国每日新增发病人数,兰州大学开发了COVID-19流行病全球预测系统(GPCP).在本文的研究中,我们使用集合经验模态分解(EEMD)模型和自回归-移动平均(ARMA)模型对GPCP的... 2020年,新型冠状病毒肺炎(COVID-19)在世界范围内迅速传播.为准确预测各国每日新增发病人数,兰州大学开发了COVID-19流行病全球预测系统(GPCP).在本文的研究中,我们使用集合经验模态分解(EEMD)模型和自回归-移动平均(ARMA)模型对GPCP的预测结果进行改进,并对发病人数较少或处于发病初期,不完全符合传染病规律,GPCP模型无法预测的国家进行直接预测.从结果来看,使用该方法修正预测结果,古巴等国家预测误差均大幅下降,且预测趋势更接近真实情况.对于萨尔瓦多等发病人数较少的国家直接进行预测,相对误差较小,预测结果较为准确.该方法对于改进预测结果和直接预测均较为有效. 展开更多
关键词 COVID-19 预测 EEMD-ARMA混合方法 历史数据
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新冠肺炎流行病学模型的最优参数化 被引量:2
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作者 Li Zhang Jianping Huang +5 位作者 Haipeng Yu Xiaoyue liu Yun Wei Xinbo Lian chuwei liu Zhikun Jing 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第4期58-62,共5页
现如今,新冠肺炎(COVID-19)严重威胁着世界各国人民的生命健康.许多流行病学模型已经被用于为政策制定者和世界卫生组织提供决策参考.为了更加深刻的理解疫情趋势的变化特征,许多参数优化算法被用于反演模型参数.本文提议使用结合了高斯... 现如今,新冠肺炎(COVID-19)严重威胁着世界各国人民的生命健康.许多流行病学模型已经被用于为政策制定者和世界卫生组织提供决策参考.为了更加深刻的理解疫情趋势的变化特征,许多参数优化算法被用于反演模型参数.本文提议使用结合了高斯-牛顿法和梯度下降法的Levenberg–Marquardt(LMA)算法来优化模型参数.使用四个病例数相对较多的国家来验证这一算法的优势:相较于传统流行病学模型模拟曲线过早过快的到达峰值,应用LMA的Statistical-SIR(Statistical-Susceptible–Infected–Recovered)模型可以更好地拟合实际疫情曲线. 展开更多
关键词 新冠肺炎 统计方法 LEVENBERG-MARQUARDT 算法 SIR模型
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Development of the second version of Global Prediction System for Epidemiological Pandemic 被引量:1
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作者 Jianping Huang Li Zhang +9 位作者 Bin Chen Xiaoyue liu Wei Yan Yingjie Zhao Siyu Chen Xinbo Lian chuwei liu Rui Wang Shuoyuan Gao Danfeng Wang 《Fundamental Research》 CAS CSCD 2024年第3期516-526,共11页
Coronavirus disease 2019(COvID-19)is a severe global public health emergency that has caused a major cri-sis in the safety of human life,health,global economy,and social order.Moreover,CovID-19 poses significant chall... Coronavirus disease 2019(COvID-19)is a severe global public health emergency that has caused a major cri-sis in the safety of human life,health,global economy,and social order.Moreover,CovID-19 poses significant challenges to healthcare systems worldwide.The prediction and early warning of infectious diseases on a global scale are the premise and basis for countries to jointly fight epidemics.However,because of the complexity of epidemics,predicting infectious diseases on a global scale faces significant challenges.In this study,we developed the second version of Global Prediction System for Epidemiological Pandemic(GPEP-2),which combines statis-tical methods with a modified epidemiological model.The GPEP-2 introduces various parameterization schemes for both impacts of natural factors(seasonal variations in weather and environmental impacts)and human so-cial behaviors(government control and isolation,personnel gathered,indoor propagation,virus mutation,and vaccination).The GPEP-2 successfully predicted the COVID-19 pandemic in over 180 countries with an average accuracy rate of 82.7%.It also provided prediction and decision-making bases for several regional-scale CovID-19 pandemic outbreaks in China,with an average accuracy rate of 89.3%.Results showed that both anthropogenic and natural factors can affect virus spread and control measures in the early stages of an epidemic can effectively control the spread.The predicted results could serve as a reference for public health planning and policymaking. 展开更多
关键词 COVID-19 Epidemiological model Prediction GPEP SEIR Statistical-dynamic
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新冠肺炎疫情全球预测系统 被引量:16
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作者 黄建平 张立 +13 位作者 刘晓岳 魏韵 刘楚薇 连鑫博 黄忠伟 丑纪范 刘兴荣 李汛 杨克虎 汪金国 梁洪彬 顾仟青 杜鹏岳 张廷瀚 《Science Bulletin》 SCIE EI CAS CSCD 2020年第22期1884-1887,M0003,共5页
目前,一种可以引起病毒性肺炎(COVID-19)的新型冠状病毒(SARS-Co-V-2)已经蔓延至200多个国家,确诊人数超过900万,对全球公共卫生系统构成了严重威胁.为帮助世界卫生组织和国际决策者实施有效的管控措施,我们开发了一个全球新冠疫情预测... 目前,一种可以引起病毒性肺炎(COVID-19)的新型冠状病毒(SARS-Co-V-2)已经蔓延至200多个国家,确诊人数超过900万,对全球公共卫生系统构成了严重威胁.为帮助世界卫生组织和国际决策者实施有效的管控措施,我们开发了一个全球新冠疫情预测系统.疫情预测系统充分利用团队30年来在统计-动力气候预测的先进技术,将流行病学模型与实时更新的疫情、气象和环境数据相结合,构建了世界上第一个全球疫情预测系统.系统可以较好地预测世界各个国家每日新增确诊病例数的主要特征和长期趋势,预测结果显示东亚与欧洲地区疫情得到初步控制,美洲与非洲地区疫情仍处于大流行阶段. 展开更多
关键词 病毒性肺炎 预测系统 环境数据 全球公共卫生 气候预测 非洲地区 管控措施 实时更新
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