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Differences between Convective and Stratiform Precipitation Budgets in a Torrential Rainfall Event

Advances in Atmospheric Sciences 2019年第5期36卷 495-509页

作者： yongjie huang Yaping WANG Xiaopeng CUI Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

Differences in rainfall budgets between convective and stratiform regions of a torrential rainfall event were investigated using high-resolution simulation data produced by the Weather Research and Forecasting(WRF) model. The convective and stratiform regions were reasonably separated by the radar-based convective–stratiform partitioning method, and the threedimensional WRF-based precipitation equation combining water vapor and hydrometeor budgets was further used to analyze the rainfall budgets. The results showed that the magnitude of precipitation budget processes in the convective region was one order larger than that in the stratiform region. In convective/stratiform updraft regions, precipitation was mainly from the contribution of moisture-related processes, with a small negative contribution from cloud-related processes. In convective/stratiform downdraft regions, cloud-related processes played positive roles in precipitation, while moisture-related processes made a negative contribution. Moisture flux convergence played a dominant role in the moisture-related processes in convective or stratiform updraft regions, which was closely related to large-scale dynamics. Differences in cloud-related processes between convective and stratiform regions were more complex compared with those in moisture-related processes.Both liquid-and ice-phase microphysical processes were strong in convective/stratiform updraft regions, and ice-phase processes were dominant in convective/stratiform downdraft regions. There was strong net latent heating within almost the whole troposphere in updraft regions, especially in the convective updraft region, while the net latent heating(cooling) mainly existed above(below) the zero-layer in convective/stratiform downdraft regions.

关键词： convective rainfall stratiform rainfall precipitation budget updraft region downdraft region

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Impact of Mid-and Upper-Level Dry Air on Tropical Cyclone Genesis and Intensification:A Modeling Study of Durian(2001)

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Advances in Atmospheric Sciences 2018年第12期35卷 1505-1521页

作者： Yaping WANG yongjie huang Xiaopeng CUI Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China

The impact of mid-and upper-level dry air,represented by low relative humidity(RH)values,on the genesis of tropical cyclone(TC)Durian(2001)in the South China Sea was investigated by a series of numerical experiments using the Weather Research and Forecasting model.The mid-level RH was lowered in different regions relative to TC Durian(2001)’s genesis location.Results suggest that the location of dry air was important to Durian(2001)’s genesis and intensification.The rapid development of the TC was accompanied by sustained near-saturated mid-and upper-level air,whereas low humidity decelerated its development.Water vapor budget analysis showed that moisture at mid and upper levels was mainly supplied by the vertical convergence of moisture flux and the divergence terms,and consumed by the condensation process.The horizontal convergence of moisture flux term supplied moisture in the air moistening process but consumed moisture in the air drying process.With a dryer mid-and upper-level environment,convective and stratiform precipitation were both inhibited.The upward mass fluxes and the diabatic heating rates associated with these two precipitation types were also suppressed.Generally,convection played the dominant role,since the impact of the stratiform process on vertical mass transportation and diabatic heating was much weaker.The vorticity budget showed that the negative vorticity convergence term,which was closely related to the inhibited convection,caused the vorticity to decrease above the lower troposphere in a dryer environment.The negative vorticity tendency is suggested to slow down the vertical coherence and the development rate of TCs.

关键词： tropical cyclone formation mid-and upper-level dry air WRF water vapor budget convective and stratiform precipitation

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Surface Rainfall Processes during the Genesis Period of Tropical Cyclone Durian(2001)

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Advances in Atmospheric Sciences 2019年第4期36卷 451-464页

作者： Yaping WANG yongjie huang Xiaopeng CUI Key Laboratory of Cloud-Precipitation Physics and Severe Storms (LACS) Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

The rainfall processes during the formation of tropical cyclone(TC) Durian(2001) were investigated quantitatively using the three-dimensional(3 D) WRF-based precipitation equation. The rain rate(PS) decreased slightly as the TC approached to formation, and then increased as Durian began to intensify. The rate of moisture-related processes(QWV) in the equation contributed around 80% to PSbefore TC genesis, and made more contribution during and after TC genesis. The rate of hydrometeor-related processes(QCM) contributed about 20% before TC formation, followed by less contribution during and after TC formation. QWVwere dominated by the 3 D moisture flux advection rate(QWVA), while the surface evaporation rate(QWVE) also played an important role. Just before TC genesis, moisture from QWVAand QWVEhelped the local atmosphere moisten(negative QWVL). QCMwere determined by the 3 D hydrometeor advection rates(QCLAand QCIA) and the local change rates of hydrometeors(QCLLand QCIL). During TC formation, QCMlargely decreased and then reactivated as Durian began to intensify, accompanied by the development of TC cloud. Both the height and the strength of the net latent heating center associated with microphysical processes generally lowered before and during TC genesis, resulting mainly from lessening deposition and condensation. The downward shift of the net latent heating center induced a more bottom-heavy upward mass flux profile, suggesting to promote lower-tropospheric convergence in a shallower layer, vorticity amplification and TC spin-up.

关键词： surface rainfall processes tropical cyclone formation three-dimensional precipitation equation latent heating

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Compressive failure analysis of unidirectional carbon/epoxy composite based on micro-mechanical models

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Chinese Journal of Aeronautics 2017年第6期30卷 1907-1918页

作者： Wei SUN Zhidong GUAN Zengshan LI Mi ZHANG yongjie huang School of Aeronautic Science and Engineering Beihang University Beijing 100083 China

A 2D micro-mechanical model was proposed to study the compressive failure of Uni Directional（UD） carbon/epoxy composite. Considering the initial imperfection and strength distribution of the fiber, the plasticity and ductile damage of the matrix, the failure of T300/914 UD composite under longitudinal compression and in-plane combined loads was simulated by this model. Simulation results show that the longitudinal compressive failure of the UD composite is caused by the plastic yielding of the matrix in kink band, and the fiber initial imperfection is the main reason for it. Under in-plane combined loads, the stress state of the matrix in kink band is changed, which affects the longitudinal compressive failure modes and strength of UD composite.The failure envelope of r_1–s_（12） and r_1–r_2 are obtained by the micro-mechanical model. Meanwhile,the compressive failure mechanism of the UD composite is analyzed. Numerical results agree well with the experimental data, which verifies the validity of the micro-mechanical model.

关键词： Micro-mechanical model Unidirectional composite Initial imperfection Matrix plasticity Ductile damage Kink band

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Correlation between Climatic Factors and Genetic Diversity of Phrynocephalus forsythii

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Asian Herpetological Research 2019年第4期10卷 270-275页

作者： Yue QI Wei ZHAO yongjie huang Xiaoning WANG Yangyang ZHAO Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution School of Life SciencesLanzhou UniversityLanzhou 730000China School of Nature Conservation Beijing Forestry UniversityBeijing 100083China

Global climate change is a threat to animals in nearly all biomes and ecosystems, especially for ectotherm whose life activities highly depend on environmental thermal regime. Population genetic diversity which is essential for adaptation to environmental change is a useful index for long-term species survival. In this paper, genetic diversity of eight Phrynocephalus forsythii population which distributed in Tarim Basin, China, were evaluated based on three mtDNA gene and its correlation with environment factors were investigated using RDA. Our result revealed that, the level of genetic diversity of P. forsythii populations was related to its location but there was no significant correlation between genetic distances and geographic distances in P. forsythii. However, we find that mtDNA of P. forsythii was subjected to selection pressure during evolution and population genetic diversity was significantly positively related to variation coefficient of rainfall(VCR) and altitude(AL), while significantly negatively related to longitude(N) and annual average temperature(AAT). Our result supported the previous prediction that excessive ambient heat is a threat to P. forsythii.

关键词： climatic factors genetic diversity selection pressure Phrynocephalus forsythii Tarim Basin

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基于多重筛选的深度神经网络应用于航班延误预测的方法研究

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民航学报 2024年第3期8卷 17-28页

作者：黄雍杰南京中科航港技术有限公司

从全球民航信息化发展态势看,以新一代数据驱动和AI技术融合应用为主要特征的智慧民航建设正全方位重塑民航业的形态。本文将论述如何使用机器学习和深度神经网络建模来预测宏观航班延误态势,并把预测结果作为次年航延保费系数调整参考... 详细信息

从全球民航信息化发展态势看,以新一代数据驱动和AI技术融合应用为主要特征的智慧民航建设正全方位重塑民航业的形态。本文将论述如何使用机器学习和深度神经网络建模来预测宏观航班延误态势,并把预测结果作为次年航延保费系数调整参考。研究将从数据处理、数据分析、预测建模、预测结果应用全流程进行阐述,总结出可适用于民航其他领域预测能力的方法论。文中也将以国内机场“航班地面保障时间预测”为例,讨论该方法论在机场运行资源优化等场景的应用,为大数据+深度学习赋能运行智慧化给予启发,充分发挥中国民航的数据资源优势,助力实现数据资产化,实现数尽其用,用其所长。

关键词：智慧民航机器学习深度学习大数据航班延误预测地面保障节点预测

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Buckling and post-buckling behavior of titanium alloy stiffened panels under shear load

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Chinese Journal of Aeronautics 2019年第3期32卷 619-626页

作者： Yuru SU Zhidong GUAN Xin WANG Zengshan LI Jun GUO yongjie huang School of Aeronautic Science and Engineering Beihang University

Titanium alloy has been increasingly applied in aviation industry due to its superior performance. However, the titanium alloy structures are less studied. This work investigates the structural behavior of Ti6Al4V titanium alloy stiffened panels under in-plane shear load by experiments and numerical analysis. After the shear tests, the buckling instability, the post-buckling process and the failure mechanism of the specimen were obtained. The Finite Element(FE) models were established with the subsequent validation verification. A parametric analysis was implemented to study the influence of stringer thickness and stringer height on the behavior of the stiffened panels. The results show that after the initial local buckling on the skin, the buckling mode jumps several times with the increase of load. The stringers twist when the load reaches a certain level, and finally the structure damages due to the plastic deformation and the global buckling. The shear clip has little effect on the buckling and failure loads. Compared to the relatively large effect on the buckling load, the influence of the stringer thickness and stringer height on the failure load is neglectable.According to the parametric analysis, the stringer thickness influences the final buckling mode and failure mode, while the stringer height affects the buckling mode transformation.

关键词： Buckling Finite Element Method(FEM) In-plane shear loading Stiffened panel Stringer height Stringer thickness Titanium alloys

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自拟清热调血汤对湿热蕴结型宫颈炎合并HPV感染的疗效以及外周血Th17、Treg细胞的调节作用

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辽宁中医杂志 2024年第2期51卷 135-138页

作者：蒋袁园黄永洁吴亚琴德清县中医院浙江德清313200 浙江大学医学院附属妇产科医院浙江杭州310006

目的探讨自拟清热调血汤治疗湿热内蕴型宫颈炎合并人乳头瘤病毒(human papillomavirus,HPV)感染的疗效以及对外周血T辅助细胞17(T helper cell 17,Th17)、调节性T细胞(regulatory T cell,Treg)水平的影响。方法回顾性分析2018年1月—202... 详细信息

目的探讨自拟清热调血汤治疗湿热内蕴型宫颈炎合并人乳头瘤病毒(human papillomavirus,HPV)感染的疗效以及对外周血T辅助细胞17(T helper cell 17,Th17)、调节性T细胞(regulatory T cell,Treg)水平的影响。方法回顾性分析2018年1月—2022年1月该院收治的64例湿热内蕴型宫颈炎合并HPV感染患者,按不同的治疗方法分为两组,各32例。对照组给予重组人干扰素α-2b凝胶干预;治疗组在对照组干预基础上给予自拟清热调血汤内服。两组连续治疗3个月。比较两组HPV-DNA转阴率、湿热内蕴证症状评分、临床疗效、外周血Th17与Treg细胞水平、不良反应。结果治疗3个月后,治疗组患者的HPV-DNA转阴率(90.63%,29/32)较对照组(65.63%,21/32)显著上调(P0.05)。结论在西医常规干预措施的基础上,本组自拟清热调血汤治疗湿热内蕴型宫颈炎合并HPV感染的疗效更优,能提高HPV转阴率,促进中医证候改善,降低不良反应,以及下调外周血中Th17和Treg细胞水平。

关键词：宫颈炎清热调血汤湿热内蕴证 T辅助细胞17 调节性T细胞

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Taxonomic status of Chinese blue sheep(Pseudois nayaur):new evidence of a distinct subspecies

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Integrative Zoology 2020年第3期15卷 202-212页

作者： Hui GAO Nannan LI yongjie huang Fujie QIAO Junle LI Zongzhi LI Yanxiang LI Zhenghuan WANG Liwei TENG Zhensheng LIU College of Wildlife and Protected Area Northeast Forestry UniversityHarbinChina Forestry Science and Technology Research Institute of Greater Hinggan in Inner Mongolia YakeshiChina School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina School of Life Sciences Lvliang UniviersityLvliangChina School of Life Sciences East China Normal UniversityShanghaiChina Key Laboratory of Conservation Biology National Forestry and Grassland AdministrationHarbinChina

The blue sheep is an endemic species to the Qinghai-Tibet Plateau and surrounding regions.It has been regarded as having 2 subspecies:Pseudois nayaur nayaur and P.n.szechuanensis.However,such a classification remains controversial.Herein,we analyze 10 microsatellite loci and part of the mitochondrial control region for clarification in such taxonomic debates.We use samples from 168 individuals from 6 geographic populations covering almost all the distribution areas of the species in China to carry out comparisons.Phylogenetic trees derived from both the microsatellite and mitochondrial markers combined with the discriminant analysis of principal components(DAPC)and the STRUCTURE analysis reveal that the individuals in the Helan Mountains are well grouped with a distinct evolutionary lineage and are significantly different from the other populations of P.n.szechuanensis according to Fst values,implying that this isolated population should be categorized as a valid subspecies;namely,Pseudois nayaur alashanicus.The isolation-by-distance(IBD)analysis shows a significant positive relationship between genetic and geographical distances among the populations.

关键词： blue sheep isolation by distance microsatellite mtDNA control region taxonomy

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2014年-2019年大同市环境空气质量的特征分析

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佳木斯大学学报（自然科学版） 2024年第5期42卷 168-171页

作者：刘宝亮黄泳杰山西大同大学数学与统计学院山西大同037009

采用统计方法分析了2014-2019年大同市环境空气质量的变化特征,结果表明:大同市第一季度的空气质量与PM 2.5的含量呈现高度正相关;第二季度空气质量整体最好,但是臭氧含量最高;第三季度污染程度上升;第四季度的空气质量最差,与诸多污染... 详细信息

采用统计方法分析了2014-2019年大同市环境空气质量的变化特征,结果表明:大同市第一季度的空气质量与PM 2.5的含量呈现高度正相关;第二季度空气质量整体最好,但是臭氧含量最高;第三季度污染程度上升;第四季度的空气质量最差,与诸多污染物有关;同一年的空气污染物含量变化呈现出明显的规律性。

关键词：大同市环境空气质量空气污染物描述性统计相关性分析

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