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Convective Storm VIL and Lightning Nowcasting Using Satellite and Weather Radar Measurements Based on Multi-Task Learning Models

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Advances in Atmospheric Sciences 2023年第5期40卷 887-899页

作者： Yang LI Yubao LIU Rongfu SUN fengxia guo Xiaofeng XU Haixiang XU Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and TechnologyNanjing 210044China Precision Regional Earth Modeling and Information Center Nanjing University of Information Science and TechnologyNanjing 210044China Jibei Electric Power Company Beijing 100054China China Meteorological Administration Beijing 100081China

Convective storms and lightning are among the most important weather phenomena that are challenging to forecast.In this study,a novel multi-task learning(MTL)encoder-decoder U-net neural network was developed to forecast convective storms and lightning with lead times for up to 90 min,using GOES-16 geostationary satellite infrared brightness temperatures(IRBTs),lightning flashes from Geostationary Lightning Mapper(GLM),and vertically integrated liquid(VIL)from Next Generation Weather Radar(NEXRAD).To cope with the heavily skewed distribution of lightning data,a spatiotemporal exponent-weighted loss function and log-transformed lightning normalization approach were developed.The effects of MTL,single-task learning(STL),and IRBTs as auxiliary input features on convection and lightning nowcasting were investigated.The results showed that normalizing the heavily skew-distributed lightning data along with a log-transformation dramatically outperforms the min-max normalization method for nowcasting an intense lightning event.The MTL model significantly outperformed the STL model for both lightning nowcasting and VIL nowcasting,particularly for intense lightning events.The MTL also helped delay the lightning forecast performance decay with the lead times.Furthermore,incorporating satellite IRBTs as auxiliary input features substantially improved lightning nowcasting,but produced little difference in VIL forecasting.Finally,the MTL model performed better for forecasting both lightning and the VIL of organized convective storms than for isolated cells.

关键词： convection/lightning nowcasting multi-task learning geostationary satellite weather radar U-net model

Estimation of Lightning-Generated NO_(x) in the Mainland of China Based on Cloud-to-Ground Lightning Location Data

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Advances in Atmospheric Sciences 2023年第1期40卷 129-143页

作者： Qi LI fengxia guo Xiaoyu JU Ze LIU Mingjun GAN Kun ZHANG Binbin CAI Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science&TechnologyNanjing 210044China Huangshi Meteorological Bureau Huangshi 435002China Anhui meteorological disaster prevention center Hefei 230061China

Lightning-generated nitrogen oxides(LNO_(x))have a major influence on the atmosphere and global climate change.Therefore,it is of great importance to obtain a more accurate estimation of LNO_(x).The aim of this study is to provide a reference for the accurate estimation of the total LNO_(x) in the mainland of China based on cloud-to-ground lightning(CG)location data from 2014 to 2018.The energy of each CG flash was based on the number of return strokes per CG flash,the peak current of each return stroke,and the assumed CG breakdown voltage.The energy of intracloud lightning(IC)was based on the estimated frequencies of IC and the assumed energy of each IC flash.Combining the energy of lightning and the number of nitric oxide(NO)molecules produced by unit energy(ρno),the total LNO_(x) production in the mainland of China was determined.The LNO_(x) in the mainland of China estimated in this study is in the range(0.157-0.321)×10^(9) kg per year[Tg(N)yr-1],which is on the high end of other scholars’works.Negative cloud-to-ground lightning(NCG)flashes produce the most moles of NO_(x),while positive cloud-to-ground lightning(PCG)flashes produce the least total moles of NO_(x).The breakdown voltage of PCG is greater than that of IC or NCG,while the latter has a greater output of LNO_(x).

关键词： cloud-to-ground lightning location lightning peak current lightning breakdown voltage nitrogen oxide(NO_(x))

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泰安市东平县面包蒜的形成及防治技术

长江蔬菜 2024年第13期 69-71页

作者：郭凤霞东平县大羊镇农业生产综合服务队山东泰安271503

泰安市东平县大羊镇区域化种植大蒜历史悠久,但是近年来由于重茬、管理不当等原因,“面包蒜”片状发生,给种植户带来了极大的困扰。通过田间调查、问询种植户,得出了“面包蒜”的发生与氮肥过量使用有直接关系,同时也与播期、温度、光... 详细信息

泰安市东平县大羊镇区域化种植大蒜历史悠久,但是近年来由于重茬、管理不当等原因,“面包蒜”片状发生,给种植户带来了极大的困扰。通过田间调查、问询种植户,得出了“面包蒜”的发生与氮肥过量使用有直接关系,同时也与播期、温度、光照、管理措施等有关的结论。

关键词：大羊镇面包蒜形成原因防治

Relationship between Lightning Activity and Tropospheric Nitrogen Dioxide and the Estimation of Lightning-produced Nitrogen Oxides over China

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Advances in Atmospheric Sciences 2017年第2期34卷 235-245页

作者： fengxia guo Xiaoyu JU Min BAO Ganyi LU Zupei LIU Yawen LI Yijun MU Key Laboratory of Meteorological Disaster Ministry of Education Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science and TechnologyNanjing 210044China Anhui Meteorological Disaster Prevention Center Anhui 230061China

To better understand the relationship between lightning activity and nitrogen oxides （NOx） in the troposphere and to estimate lightning-produced NOx （LNOx） production in China more precisely, spatial and temporal distributions of vertical column densities of tropospheric nitrogen dioxide （NO2 VCDs） and lightning activity were analyzed using satellite measure- ments. The results showed that the spatial distribution of lightning activity is greater in the east than in the west of China, as with NO2 VCDs. However, the seasonal and annual variation between lightning and NO2 density show different trends in the east and west. The central Tibetan Plateau is sparsely populated without modem industry, and NO2 VCDs across the plateau are barely affected by anthropogenic sources. The plateau is an ideal area to study LNOx. By analyzing 15 years of satellite data from that region, it was found that lightning density is in strong agreement with annual, spatial and seasonal variations of NO2 VCDs, with a correlation coefficient of 0.79 from the linear fit. Combining Beirle＇s method and the linear fit equation, LNOx production in the Chinese interior was determined to be 0.07 （0.02-0.27） TgN yr-1 for 1997-2012, within the range of 0.016-0.384 TgN yr-1 from previous estimates.

关键词： lightning tropospheric NO2 LNOx

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余甘果酱的研制及其体外降脂功效研究

美食研究 2024年第2期41卷 83-89页

作者：李凤霞陆燕媛郭黎香闽南师范大学生物科学与技术学院福建漳州363000

以余甘果、山楂为原料,辅以一定的荷叶、葛根、薏苡仁浸提液,研制一种具有降脂功效的余甘果酱。以感官评价、黏度、色差为评价指标,采用单因素及正交试验,确定余甘果酱的最佳配方,并研究其体外降脂功效。结果表明:以余甘果和山楂总质量... 详细信息

以余甘果、山楂为原料,辅以一定的荷叶、葛根、薏苡仁浸提液,研制一种具有降脂功效的余甘果酱。以感官评价、黏度、色差为评价指标,采用单因素及正交试验,确定余甘果酱的最佳配方,并研究其体外降脂功效。结果表明:以余甘果和山楂总质量为基准,余甘果酱最佳参数为余甘果和山楂质量比97∶3、木糖醇添加量30%、蜂蜜添加量22%、黄原胶添加量0.4%。体外降脂功效表明:余甘果酱对花生油的吸附量为9.82 mg/g,对胰脂肪酶能起一定的抑制作用,且随着浓度的增加抑制效果显著增大;余甘果酱在pH 7.0条件下对胆固醇的吸附量达176.08 mg/g。余甘果酱酸甜可口,有较好的降脂功效。

关键词：余甘果酱降脂功效正交试验

身体被他人接纳量表第2版测评成年人的效度和信度

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中国心理卫生杂志 2024年第3期38卷 283-288页

作者：郭风霞黄喜珊陈苗黄可钰高静华南师范大学心理学院广州510631

目的:引进身体被他人接纳量表第2版(BAOS-2),检验BAOS-2在成年人群体的效度和信度。方法:选取616名成年人(年龄18~56岁),检验量表的结构效度及内部一致性信度,以身体欣赏量表第2版(BAS-2)、身体功能欣赏量表(FAS)、自我同情量表(SCS)、... 详细信息

目的:引进身体被他人接纳量表第2版(BAOS-2),检验BAOS-2在成年人群体的效度和信度。方法:选取616名成年人(年龄18~56岁),检验量表的结构效度及内部一致性信度,以身体欣赏量表第2版(BAS-2)、身体功能欣赏量表(FAS)、自我同情量表(SCS)、自尊量表(SES)、生活满意度量表(SWLS)为效标考察量表的效标关联效度;随机选取其中55名成年人间隔2周进行重测。结果:探索性因子分析提取1个因子,各条目的因子负荷在0.59~0.76之间;验证性因子分析显示单因子模型拟合较好(χ^(2)/df=2.99,CFI=0.91,GFI=0.90,TLI=0.89,RMR=0.04,RMSEA=0.08);BAOS-2得分与BAS-2、FAS、SCS、SES和SWLS得分均正相关(r=0.43~0.66,均P<0.001)。BAOS-2的Cronbachα系数为0.90,2周后的重测信度(ICC)为0.65。结论:身体被他人接纳量表第2版(BAOS-2)中文版具有良好的效度和信度。

关键词：身体被他人接纳量表第2版身体意象效度信度

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太空诱变膜荚黄芪种质资源表型特征变异分析

干旱地区农业研究 2024年第3期42卷 1-12页

作者：李红玲陈垣郭凤霞许宏亮李瑞霞甘肃农业大学农学院/甘肃农业大学生命科学技术学院/甘肃省干旱生境作物学国家重点实验室甘肃兰州730070 天津市现代中药资源研究企业重点实验室/天津天士力现代中药资源有限公司天津300410

以膜荚黄芪太空搭载种子建立的33D、22H群体及未搭载原种(CK)群体的SP2代成药株为研究对象,对19个表型性状进行特征变异及多样性分析,以筛选具有优异性状的膜荚黄芪种质资源。结果表明:诱变后代群体的19个性状变异幅度、遗传多样性存在... 详细信息

以膜荚黄芪太空搭载种子建立的33D、22H群体及未搭载原种(CK)群体的SP2代成药株为研究对象,对19个表型性状进行特征变异及多样性分析,以筛选具有优异性状的膜荚黄芪种质资源。结果表明:诱变后代群体的19个性状变异幅度、遗传多样性存在不同程度差异,33D、22H群体及CK群体地上部分的4个质量性状的变异系数CV范围分别为0.35~0.78、0.38~0.84、0.41~0.64,即变异幅度表现为22H>33D>CK,遗传多样性指数H′范围分别为1.67~2.13、1.66~2.02、1.44~2.21,即变化幅度为CK>33D>22H;7个数量性状的CV范围分别为0.17~0.62、0.17~0.67、0.20~0.83,H′范围分别为1.47~2.01、1.72~2.04、1.59~2.11,即变异幅度表现均为CK>22H>33D;8个产量构成性状的CV范围分别为0.09~0.53、0.15~0.55、0.09~0.97,即变化幅度为CK>22H>33D,H′范围分别为1.81~2.09、1.73~2.06、1.59~2.03,即变化幅度为33D>22H>CK。通过主成分因子分析将诱变后代群体植株的12个数量性状指标简化为4个主因子,33D和22H群体数量性状累计贡献率均大于CK,分别达68.669%和70.414%,并筛选出二级分枝数、单根干质量、有效根长、侧根数、根长、折干率可作为膜荚黄芪评价代表性指标;诱变后SP2代地上部性状隶属函数值小于CK,产量构成性状隶属函数值大于CK。通过隶属函数和聚类分析将诱变后SP2代的2个群体分别归为3类不同类型植株(即Ⅰ、Ⅱ和Ⅲ型),第Ⅰ类群为良好类、第Ⅱ类群为优势类、第Ⅲ类群为后备类,综合评价筛选出性状优异种质39份、产量构成性状优异种质16份、矮株型高产种质3份。

关键词：膜荚黄芪太空诱变表型特征变异分析种质筛选

贯叶金丝桃(Hypericum perforatum)种子灌浆与发芽特性研究

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干旱地区农业研究 2024年第2期42卷 9-16页

作者：张丹陈垣郭凤霞梁伟赵小强景岩樊睿甘肃农业大学农学院干旱生境作物学国家重点实验室甘肃兰州730070 甘肃农业大学生命科学技术学院甘肃兰州730070 四川康弘中药材种植有限公司四川成都748100

贯叶金丝桃(Hypericum perforatum)是抗抑郁中药的基原植物,以有性繁殖为主,种子微小。为了揭示贯叶金丝桃种子发育规律,明确种子适宜采收期,以甘肃礼县栽培的2年生贯叶金丝桃为研究对象,于开花后第5天开始,每隔3 d测定种子粒重变化动态... 详细信息

贯叶金丝桃(Hypericum perforatum)是抗抑郁中药的基原植物,以有性繁殖为主,种子微小。为了揭示贯叶金丝桃种子发育规律,明确种子适宜采收期,以甘肃礼县栽培的2年生贯叶金丝桃为研究对象,于开花后第5天开始,每隔3 d测定种子粒重变化动态,并拟合Logistic曲线方程,最后测定各时期采收种子的发芽指标。结果表明:贯叶金丝桃种子灌浆持续期44 d,籽粒干质量变化符合Logistic生长曲线:开花后第5~11天为渐增期,第11~32天为快增期,第32~44天进入稳增期后略有下降。在灌浆过程中,种子鲜质量呈先升高后下降的动态变化趋势,在花后第32天达到最大值0.2697 g;灌浆速率和脱水速率呈波动趋势,种子干质量与平均灌浆速率、灌浆持续期呈极显著正相关,与含水量呈极显著负相关。种子发芽率和发芽指数在开花后44天达到最大,发芽势在开花后41天达到最大,发芽率、发芽势和发芽指数均与灌浆持续期呈极显著正相关,与含水量呈极显著负相关。以上说明甘肃礼县贯叶金丝桃繁种时以开花后44天左右(8月9日前后)为种子采收适宜期,过早采收和延迟采收均影响种子发芽质量。

关键词：贯叶金丝桃种子灌浆发芽特性采收期 Logistic模型

On the Factors Analysis of Affecting Listening Comprehension in Learning Foreign Language

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International English Education Research 2015年第2期 61-63页

作者： fengxia guo Zhengzhou University of Science and Technology No. I Xueyuan Road Erqi District Zhengzhou City Henan province China 450064