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A 10-yr Rainfall and Cloud-to-Ground Lightning Climatology over Coastal and Inland Regions of Guangdong,China during the Pre-Summer Rainy Season

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Journal of Meteorological Research 2024年第3期38卷 469-488页

作者： Yuqing RUAN Rudi XIA xinghua bao Dong ZHENG Yan SHEN Jinfang YIN State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing210044China National Meteorological Information Centre China Meteorological AdministrationBeijing100081China

A comparative analysis of the spatiotemporal distribution characteristics of rainfall and lightning in coastal and inland areas of Guangdong Province of China during the pre-summer rainy season(PSRS)from 2008 to 2017 reveals distinct *** the inland target region(ITR),rainfall is concentrated in the central and eastern mountainous *** exhibits a bimodal diurnal variation,with peaks in the afternoon and *** afternoon peak becomes more pronounced during the post-monsoon-onset period because of the increased rainfall ***,in the coastal target region(CTR),rainfall concentrates around mountainous ***,CTR’s rainfall is weaker than ITR’s during the pre-monsoon-onset period,primarily associated with the lower-level moisture outflow in CTR,but it strengthens significantly during the post-monsoon-onset period owing to enhanced moisture ***’s diurnal rainfall variation transitions from bimodal to a single broad peak during the post-monsoon-onset period,influenced by changes in both rainfall frequency and *** contrast to rainfall,the spatiotemporal distribution of lightning centers remains relatively stable during the *** strongest center is located over ITR’s plains west of the rainfall center,with a secondary center in the western plains of *** activity significantly increases during the post-monsoon-onset period,particularly in ITR,primarily because of the increased lightning *** diurnal lightning flash density and lightning hours show a single afternoon peak in the two target regions,and the timing of the peak in ITR is approximately two hours later than in *** circulation analysis indicates that during early morning,the lower atmosphere is nearly neutral in *** advected warm,moist,unstable airflow,combined with topography,favors convection *** the afternoon,solar radiation increases thermal instability,further enhancing the convection frequency and in

关键词： rainfall lightning spatiotemporal distribution diurnal variation pre-summer rainy season

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Efficiently Improving Ensemble Forecasts of Warm-Sector Heavy Rainfall over Coastal Southern China: Targeted Assimilation to Reduce the Critical Initial Field Errors

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气象学报:英文版 2023年第4期37卷 486-507页

作者： xinghua bao Rudi XIA Yali LUO Jian YUE State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences(CAMS)China Meteorological Administration(CMA)Beijing 100081 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044 CMA Earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing 100081

Warm-sector heavy rainfall events over southern China are difficult to accurately forecast, due in part to inaccurate initial fields in numerical weather prediction models. In order to determine an efficient way of reducing the critical initial field errors, this study conducts and compares two sets of 60-member ensemble forecast experiments of a warm-sector heavy rainfall event over coastal southern China without data assimilation(NODA) and with radar radial velocity data assimilation(RadarDA). Yangjiang radar data, which can provide offshore high-resolution wind field information, were assimilated by using a Weather Research and Forecasting(WRF)-based ensemble Kalman filter(EnKF) system. The results show that the speed and direction errors of the southeasterly airflow in the marine boundary layer over the northern South China Sea may primarily be responsible for the forecast errors in rainfall and convection evolution. Targeted assimilation of radial velocity data from the Yangjiang radar can reduce the critical initial field errors of most members, resulting in improvements to the ensemble forecast. Specifically, RadarDA simulations indicate that radial-velocity data assimilation(VrDA) can directly reduce the initial field errors in wind speed and direction, and indirectly and slightly adjust the initial moisture fields in most members, thereby improving the evolution features of moisture transport during the subsequent forecast period. Therefore, these RadarDA members can better capture the initiation and development of convection and have higher forecast skill for the convection evolution and rainfall. The improvement in the deterministic forecasts of most members results in an improved overall ensemble forecast performance. However, VrDA sometimes results in inappropriate adjustment of the initial wind field,so the forecast skill of a few members decreases rather than increases after VrDA. This suggests that a degree of uncertainty remains about the effect of

关键词： ensemble forecast targeted assimilation warm-sector heavy rainfall

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“五化一体”核电工程施工管理体系构建与实施

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中国核电 2024年第3期17卷 321-324页

作者：鲍兴华裘锦宏吕文哲中核国电漳州能源有限公司福建漳州363300

为有效落实新时代国家质量强国战略,系统总结和推广“华龙一号”机组批量化建设中的先进施工技术,提高核电工程施工标准化水平,打造核电精品工程,以“建造精品工程、打造行业一流”为目标,介绍了应用标准化管理、标杆化管理、精细化管... 详细信息

为有效落实新时代国家质量强国战略,系统总结和推广“华龙一号”机组批量化建设中的先进施工技术,提高核电工程施工标准化水平,打造核电精品工程,以“建造精品工程、打造行业一流”为目标,介绍了应用标准化管理、标杆化管理、精细化管理、智能化管理、可视化管理等先进管理方法,建立了“五化一体”(施工标杆化、标准化、精细化、智能化、可视化、应用一体化)施工管理体系的方法。通过创示范、树样板,为核电工程每个分项或工序大批量施工前提供直观有效的质量提升样板,推广应用先进的施工工艺,引导和推动核电工程实现全过程规范化施工。

关键词：核电工程五化一体精品工程

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内蒙古大兴安岭森林火险等级预报模型研究

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林业调查规划 2024年第2期49卷 19-24页

作者：杨淑香吴宏伟董越李洪峰包兴华呼伦贝尔市气象局内蒙古海拉尔020018 根河市根森公司森调队内蒙古根河022350

为提高森林火险等级预报的准确率和及时率,减少森林资源损失。以内蒙古大兴安岭地区为研究区域,利用遥感MODIS-NDVI数据反演可燃物的湿度指数,以气象指数、植被指数、闪电指数、湿度指数共同计算得出森林火险指数,以火险指数作为内蒙古... 详细信息

为提高森林火险等级预报的准确率和及时率,减少森林资源损失。以内蒙古大兴安岭地区为研究区域,利用遥感MODIS-NDVI数据反演可燃物的湿度指数,以气象指数、植被指数、闪电指数、湿度指数共同计算得出森林火险指数,以火险指数作为内蒙古大兴安岭地区森林火险等级预报模型的量化指标,并对火险等级进行分级,获得内蒙古大兴安岭森林火险等级预报方法。该方法结合当地的实际情况,将闪电指数引入到预报模型中,并实现了定量化估测。同时,以近几年发生在该地区重特大森林火灾为例,对该预报模型进行了验证。该方法可较好地对内蒙古大兴安岭地区森林火险等级进行定量化预报。

关键词：森林可燃物 MODIS-NDVI数据含水率火险等级预报模型大兴安岭

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Assimilating Doppler radar observations with an ensemble Kalman filter for convection-permitting prediction of convective development in a heavy rainfall event during the pre-summer rainy season of South China

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Science China Earth Sciences 2017年第10期60卷 1866-1885页

作者： bao xinghua LUO YaLi SUN JiaXiang MENG ZhiYong YUE Jian State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing 210044 China CAAC East China Regional Air Traffic Administration Shanghai 200335 China Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Beijing 100871 China National Meteorological Center China Meteorological Administration Beijing 100081 China

This study examines the effectiveness of an ensemble Kalman filter based on the weather research and forecasting model to assimilate Doppler-radar radial-velocity observations for convection-permitting prediction of convection evolution in a high-impact heavy-rainfall event over coastal areas of South China during the pre-summer rainy season. An ensemble of 40 deterministic forecast experiments(40 DADF) with data assimilation(DA) is conducted, in which the DA starts at the same time but lasts for different time spans(up to 2 h) and with different time intervals of 6, 12, 24, and 30 min. The reference experiment is conducted without DA(NODA).To show more clearly the impact of radar DA on mesoscale convective system(MCS)forecasts, two sets of 60-member ensemble experiments(NODA EF and exp37 EF) are performed using the same 60-member perturbed-ensemble initial fields but with the radar DA being conducted every 6 min in the exp37 EF experiments from 0200 to0400 BST. It is found that the DA experiments generally improve the convection prediction. The 40 DADF experiments can forecast a heavy-rain-producing MCS over land and an MCS over the ocean with high probability, despite slight displacement errors. The exp37 EF improves the probability forecast of inland and offshore MCSs more than does NODA EF. Compared with the experiments using the longer DA time intervals, assimilating the radial-velocity observations at 6-min intervals tends to produce better forecasts. The experiment with the longest DA time span and shortest time interval shows the best ***, a shorter DA time interval(e.g., 12 min) or a longer DA time span does not always help. The experiment with the shortest DA time interval and maximum DA window shows the best performance, as it corrects errors in the simulated convection evolution over both the inland and offshore areas. An improved representation of the initial state leads to dynamic and thermodynamic conditions that are more conducive to

关键词：中尺度对流系统中国南方地区演变预测雷达观测多普勒雷达卡尔曼滤波同化暴雨

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On the Diurnal Cycle of Heavy Rainfall over the Sichuan Basin during 10–18 August 2020

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Advances in Atmospheric Sciences 2021年第12期38卷 2183-2200页

作者： Rudi XIA Yali LUO Da-Lin ZHANG Mingxin LI xinghua bao Jisong SUN State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Atmospheric and Oceanic Science University of MarylandCollege ParkCollege ParkMaryland 20742USA

A sustained heavy rainfall event occurred over the Sichuan basin in southwest China during 10–18 August 2020,showing pronounced diurnal rainfall variations with nighttime peak and afternoon minimum values,except on the first *** show that the westward extension of the anomalously strong western Pacific subtropical high was conducive to the maintenance of a southerly low-level jet(LLJ)in and to the southeast of the basin,which favored continuous water vapor transport and abnormally high precipitable water in the *** diurnal cycle of rainfall over the basin was closely related to the periodic oscillation of the LLJ in both wind speed and direction that was caused by the combination of inertial oscillation and terrain thermal *** nocturnally enhanced rainfall was produced by moist convection mostly initiated during the evening hours over the southwest part of the basin where high convective available potential energy with moister near-surface moist air was *** convective initiation took place as cold air from either previous precipitating clouds from the western Sichuan Plateau or a larger-scale northerly flow met a warm and humid current from the *** was the slantwise lifting of the warm,moist airflow above the cold air,often facilitated by southwest vortices and quasi-geostrophic ascent,that released the convective instability and produced heavy rainfall.

关键词： diurnal cycle heavy rainfall low-level jet inertial oscillation terrain Sichuan basin

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电子政务如何优化营商环境——基于腐败治理和政府效能的链式中介效应的实证检验

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福建师范大学学报（哲学社会科学版） 2023年第2期 94-107页

作者：王珍珍鲍星华福建师范大学经济学院福建福州350108 福州大学电气工程与自动化学院福建福州350108

营商环境竞争力已经成为衡量一个国家国际竞争力的重要标杆,越来越多的国家试图通过电子化、数字化、智慧化等手段来实现数字营商环境建设以助推营商环境优化。在电子政务与营商环境优化之间引入了腐败治理和政府效能两个中介变量,探讨... 详细信息

营商环境竞争力已经成为衡量一个国家国际竞争力的重要标杆,越来越多的国家试图通过电子化、数字化、智慧化等手段来实现数字营商环境建设以助推营商环境优化。在电子政务与营商环境优化之间引入了腐败治理和政府效能两个中介变量,探讨了电子政务影响营商环境优化的逻辑机理并提出相应的假设,实证检验了“一带一路”沿线国家电子政务影响营商环境优化的链式中介效应。电子政务显著优化了营商环境,腐败治理水平和政府效能发挥了部分中介效应作用,腐败治理又会通过作用于政府效能进一步促进营商环境优化。基于电子政务背景思考影响营商环境优化的路径,通过进一步转变政府治理理念,持续加大对电子政务项目和人力资本的投入力度,加快推进廉洁政府的建设以及提升腐败治理政策的透明性等,以达到优化营商环境的效果。

关键词：电子政务腐败治理政府效能营商环境

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基于权重的AHP判断矩阵一致性调整方法

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国防科技大学学报 2024年第1期46卷 179-186页

作者：耿正霖吴佳妮程兴华包长春国防科技大学气象海洋学院湖南长沙410073

传统的判断矩阵调整方法计算得到的权重不能最大限度地保留原始判断矩阵的信息。为此,提出一种基于权重的判断矩阵调整方法。该方法根据权重的性质,构造完全一致矩阵,利用AdaGrad最速下降法对矩阵进行拟合,使该矩阵相对于原始判断矩阵... 详细信息

传统的判断矩阵调整方法计算得到的权重不能最大限度地保留原始判断矩阵的信息。为此,提出一种基于权重的判断矩阵调整方法。该方法根据权重的性质,构造完全一致矩阵,利用AdaGrad最速下降法对矩阵进行拟合,使该矩阵相对于原始判断矩阵的总改变量最小,以其对应的权重作为矩阵的计算结果。数值计算结果表明,该方法相比于其他方法,权重对原始判断信息的保留度更高,且不需要反复进行矩阵一致性检验。

关键词：层次分析法判断矩阵一致性调整 AdaGrad

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“21·7”河南特大暴雨气象和水文雨量观测对比

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应用气象学报 2022年第6期33卷 668-681页

作者：宝兴华夏茹娣罗亚丽徐祥德中国气象科学研究院灾害天气国家重点实验室北京100081 南京信息工程大学气象灾害预报预警与评估协同创新中心南京210044

2021年“21·7”河南特大暴雨打破我国大陆小时气象观测纪录,该极端天气事件位列2021年中国十大天气气候事件第2位。已有研究使用气象地面站雨量观测资料对此次过程进行雨情分析和极值统计,但降水时空分布不均匀,单一来源资料存在不确... 详细信息

2021年“21·7”河南特大暴雨打破我国大陆小时气象观测纪录,该极端天气事件位列2021年中国十大天气气候事件第2位。已有研究使用气象地面站雨量观测资料对此次过程进行雨情分析和极值统计,但降水时空分布不均匀,单一来源资料存在不确定性。通过对比气象站和水文站雨量资料,分析两套业务观测系统记录“21·7”河南特大暴雨过程的异同,发现气象站和水文站雨量在时间和空间分布上具有很好的一致性,两者不同等级的累积降雨落区、逐日和逐时降雨演变趋势均一致性强,但累积雨量和雨强极值的空间分布和数值存在差异,两套资料在暴雨中心(过程雨量大于600 mm)的系统性偏差小于1%。气象站和水文站的融合资料呈现比单一资料更细致的降雨分布、更全面的演变特征。此外,基于融合资料发现累积雨量排名前3位的城市(郑州、鹤壁、新乡)均具有累积雨量大、小时雨强极强、强降雨集中、雨强突然增长的特征,鹤壁和新乡最强降雨时段分别比郑州晚26 h和28 h。

关键词： “21·7”河南特大暴雨气象站和水文站观测对比暴雨特征

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云南佤族三大方言族群的体成分

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人类学学报 2024年第3期43卷 458-469页

作者：高新颖宇克莉张兴华姚玥彤肖瑶程智高雯芳刘鑫包金萍天津师范大学生命科学学院天津市动物多样性保护与利用重点实验室天津师范大学体育科学学院

为了解佤族三大方言族群身体组成成分的特点与差异，本研究采用生物电阻抗法对佤族三大方言族群的阿佤564例、巴饶克佤927例、佤佤505例样本的体质量、体脂率等18项指标进行测量。统计结果显示：1)三大方言族群的内脏脂肪等级均与年龄... 详细信息

为了解佤族三大方言族群身体组成成分的特点与差异，本研究采用生物电阻抗法对佤族三大方言族群的阿佤564例、巴饶克佤927例、佤佤505例样本的体质量、体脂率等18项指标进行测量。统计结果显示：1)三大方言族群的内脏脂肪等级均与年龄呈正相关；体质量、总肌肉量、推定骨量、总能量代谢、躯干肌肉量与年龄呈负相关。2)三大方言族群的成人多为下肢脂肪率最高，躯干脂肪率次之，上肢脂肪率最低；躯干肌肉量最高，下肢肌肉量次之，上肢肌肉量最低。3)三大方言族群脂肪特征的差异更明显，佤佤族群的脂肪率和内脏脂肪等级更高，脂肪更丰富。相比于男性，三大方言族群女性的肌肉量和骨量差异较大，主要表现为阿佤族群女性总肌肉量、上肢和躯干肌肉量、推定骨量值最大。

关键词：云南佤族人体测量学体成分

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