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Advances in Atmospheric Sciences 2024年第12期41卷 2478-2494页

作者： yanqing gao Xiaofeng WANG Wei GUO Shanghai Ecological Forecasting and Remote Sensing Center Shanghai 200030China

In this study,a latent heat nudging lightning data assimilation(LDA)method independent of the flash rate was developed and tested with data from the Lightning Mapping Imager(LMI)onboard the Feng-Yun-4A(FY-4A)satellite based on the Weather Research and Forecasting(WRF)*** this LDA method,the positive temperature perturbations at the lightning location are first calculated by the difference between the moist adiabatic temperature of a lifted air parcel and the model *** positive temperature perturbations in the mixed-phase region are then assimilated by a nudging method to adjust the latent heat within the convective ***,the water vapor mixing ratio is adapted to the temperature perturbations accordingly to constrain the relative humidity to remain *** method considers the physical nature of the convective system,in contrast with other LDA methods that establish an empirical or statistical relationship between the lightning flash rates and model *** impact of this LDA method on short-term(≤6 h)forecasts was evaluated using two severe convective events in eastern China:a multi-region heavy rainfall event and a thunderstorm high-wind *** results showed that LDA could add thermodynamic information associated with the convective system to the WRF model during the nudging period,leading to a more reasonable storm *** the forecast fields,the simulations with LDA produced more realistic convective structures,resulting in an improvement in forecasts of precipitation and high winds.

关键词： FY-4A LMI lightning data assimilation latent heat nudging numerical weather prediction

Convection Initiation of a Heavy Rainfall Event in the Coastal Metropolitan Region of Shanghai on the South Side of the Meiyu Front

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Journal of Meteorological Research 2023年第2期37卷 149-173页

作者： yanqing gao Xiaofeng WANG Ying XIE Wen GU Shanghai Ecological Forecasting and Remote Sensing Center Shanghai 200030

Accurate prediction of the convection initiation(CI)in urban areas is still a challenge.A heavy rainfall event,missed by the 9-km regional operational modeling system,occurred in the coastal urban area of the Shanghai metropolitan region(SMR)in the late morning on 28 July 2020 on the warm side to the south of the Meiyu *** this study,observational analyses and convection-permitting simulations with a resolution of 3 km were conducted to investigate the CI mechanism of this rainfall *** results showed that the CI was due to the interaction of urban heat island(UHI),northwesterly outflows from the Meiyu front precipitation system(MFPS),and northeasterly sea ***,the UHI created a lifting condition producing adiabatic cooling and the vertical moisture transport in the urban ***,the mesolow generated by the UHI induced and enhanced local low-level convergence near the CI region and accelerated the northwesterly outflows and the northeasterly sea winds as they converged to the *** convection was triggered as a result of the strengthened low-level convergence when the enhanced northwesterly outflows and northeasterly sea winds approached the updraft zone caused by the UHI *** experiments with either the urban area of the SMR removed or the MFPS suppressed further revealed that the enhancement of the low-level convergence was mainly contributed by the *** outflows and sea winds transported cold and moist air to the CI region and partly offset the negative contribution of the urban drying effect to the low-level relative humidity to facilitate the development of the deep moist absolute unstable layer during the *** addition,the MFPS also contributed to the enhancement of the northeasterly sea winds by influencing the land–sea pressure contrast on the north of the SMR.

关键词： convection initiation urban heat island outflows Meiyu front precipitation system heavy rainfall

On Frequency Sensitivity and Mode Orthogonality of Flexible Robotic Manipulators

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IEEE/CAA Journal of Automatica Sinica 2016年第4期3卷 394-397页

作者： Fei-Yue Wang yanqing gao IEEE State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences Research Center of Computational Experiments and Parallel Systems the National University of Defense Technology Department of Manufacturing & Mechanical Engineering & Technology Oregon Institute of Technology

This paper presents sensitivity analysis of vibration frequencies of flexible manipulators with respect to variations of systems parameters such as rotational inertia of hub, and mass, moment, and side of tip load. Both Euler-Bernoulli and Timoshenko dynamical models of flexible manipulators are discussed. By using variational method, sensitivity indices are obtained with explicit expressions for measuring the sensitivity of frequencies. Based on variational formulations, a novel method for deriving the orthogonal relations among vibration modal shape functions of flexible manipulators is introduced. With this method, the orthogonal relations can be derived easily without invoking the tedious process of differentiation and integration by part, as commonly used in their derivation. © 2014 Chinese Association of Automation.

关键词： Dielectric waveguides Flexible manipulators Manipulators Orthogonal functions Vibration analysis

Deviation Inequality for the Number of k-Cycles in a Random Graph

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Wuhan University Journal of Natural Sciences 2009年第1期14卷 11-13页

作者： WANG yanqing gao Fuqing School of Mathematics and Statistics Wuhan UniversityWuhan 430072 Hubei China

We study the number of k-cycles in a random graph G（n, p）. We estimate the probability that a random graph contains more k-cycles than expected. In this case, the usual martingale inequality with bounded difference is not effective. By construct- ing a variable that approximates to the number of k-cycles in a random graph and using a new and extensive martingale inequality, we get the results in this paper.

关键词： random graph deviation inequality k-cycles

Magnetic properties and structure of Ni_80Fe_20/Ni_48Fe_12Cr_40 bilayer films deposited on SiO_2/Si(100) by electron beam evaporation

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Rare Metals 2007年第2期26卷 176-181页

作者： WU Ping gao yanqing QIU Hong PAN Liqing TIAN Yue Wang Fengping Department of Physics University of Science and Technology Beijing Beijing 100083 China

Ni80Fe20/Ni48Fe12Cr40 bilayer films and Ni80Fe20 monolayer films were deposited at room temperature on SiO2/Si（100） substrates by electron beam evaporation. The influence of the thickness of the Ni48Fe12Cr40 underlayer on the structure, magnetization, and magnetoresistance of the Ni80Fe20/Ni48Fe12Cr40 bilayer film was investigated. The thickness of the Ni48Fe12Cr40 layer varied from about 1 nm to 18 nm while the Ni80Fe20 layer thickness was fixed at 45 nm. For the as-deposited bilayer films the introducing of the Ni48Fe12Cr40 underlayer promotes both the （111） texture and grain growth in the Ni80Fe20 layer. The Ni48Fe12Cr40 underlayer has no significant influence on the magnetic moment of the Ni80Fe20/Ni48Fe12Cr40 bilayer film. However, the coercivity of the bilayer film changes with the thickness of the Ni48Fe12Cr40 undedayer. The optimum thickness of the Ni48Fe12Cr40 underlayer for improving the anisotropic magnetoresistance effect of the Ni80Fe20/Ni48Fe12Cr40 bilayer film is about 5 nm. With a decrease in temperature from 300 K to 81 K, the anisotropic magnetoresistance ratio of the Ni80Fe20 （45 nm）/Ni48Fe12Cr40 （5 nm） bilayer film increases linearly from 2.1% to 4.8% compared with that of the Ni80Fe20 monolayer film from 1.7% to 4.0%.

关键词： Ni80Fe20 films Ni48Fe12Cr4o seed layer structure magnetic properties

Dynamic synthetic analysis of circulation field of tropical cyclones affecting Shanghai

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Frontiers of Earth Science 2024年第2期18卷 347-363页

作者： Wen GU Caijun YUE Zhihui HAN yanqing gao Yuqi TANG Xiangyu AO Yao YAO Shanghai Ecological Forecasting&Remote Sensing Center Shanghai 200030China Shanghai Marine Meteorological Centre Shanghai 200030China Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030China Key Laboratory of Numerical Modeling for Tropical Cyclone(China Meteorological Administration) Shanghai 200030China

Eleven tropical cyclones(TCs)affected Shanghai and crossed the same latitude as Shanghai from 2007 to *** to similar tracks from best-track data,TCs that cause significant precipitation in Shanghai can be divided into three types:landfall TCs,nearshore northward TCs,and western *** on ERA5 reanalysis data,the dynamic synthesis method was used to synthesize TC circulation situations to compare thermal,dynamic,water vapor,and stability conditions within TC circulations during the period when they affected *** conclusions are as follows.1)When the three TC types are at the same latitude as Shanghai,they are all in the divergent field in the upper *** the landfall type,the subtropical high at 500 hPa is stronger and farther north than usual,and there is a high-pressure dam on the north side of the TCs.2)The warm advection of the three TC types at 925 hPa is located in the northern quadrant of the *** dynamic and water vapor conditions are good in the north-western quadrant of landfall and western TCs,and more favorable in the eastern quadrant of nearshore northward TCs.3)The favorable effects of all three types on precipitation in Shanghai come from the boundary *** vapor,upward motion,and instability conditions of landfall TCs are superior to the other two TC *** best water vapor,dynamic,and convective instability conditions are at the northern boundary in Shanghai during landfall TCs,and the main sources of water vapor in Shanghai come from the eastern and northern *** nearshore northward TCs,the main contribution to precipitation is from the eastern boundary,while better dynamic and water vapor conditions come from the western and northern boundaries during western *** above findings provide scientific and technical support for operational forecasting precipitation from TCs affecting mega-cities.

关键词： tropical cyclones dynamic synthetic analysis ERA5 reanalysis Shanghai similar track

Impulse Transient Characteristic of Grounding Grids 3

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Impulse Transient Characteristic of Grounding Grids

Preparation of Amide-Containing Insecticidal Derivatives from the Renewable Natural Productβ-Pinene

2002 3rd International Symposium on Electromagnetic Compatibility

作者： gao yanqing HE Jinliang ZENG Rong LIANG Xidong Dept.of Electrical Engineering Tsinghua University

ISBN: (纸本)0780372778

＜正＞The lightning transient characteristic of a grounding grid for substation is analyzed in detail,which especially considers the dynamic and nonlinear effects of soil ionization around grounding conductors and the inductance between grounding *** analysis results are calculated by a loss transmission-line model with distributed time-variable *** influences of structure of the grid,location of feed point,and shape of the lightning impulse current on the transient characteristic of grounding grids are discussed.

关键词： transient characteristic grounding grid lightning loss transmission line

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Journal of Renewable Materials 2023年第5期11卷 2368-2380页

作者： Jiulong Wang yanqing gao Xiaoping Rao Zongde Wang Shibin Shang Zhanqian Song Hongyan Si Shengliang Liao East China Woody Fragrance and Flavor Engineering Research Center of National Forestry and Grassland Administration Camphor Engineering Research Center of National Forestry and Grassland AdministrationCollege of ForestryJiangxi Agricultural UniversityNanchang330045China College of Plant Protection Northwest Agriculture and Forestry UniversityYangling712100China College of Chemical Engineering Huaqiao UniversityXiamen361021China Institute of Chemical Industry of Forest Products China Academy of ForestryNational Engineering Laboratory for Biomass Chemical UtilizationState Forestry Administration’s Key and Open Laboratory for Forest Chemical EngineeringJiangsu Provincial Key Laboratory for Biomass Energy and MaterialNanjing210042China

The preparation of bioactive derivatives from the renewable natural product pinene is a hot research topic in the deep processing and utilization of *** this study,β-pinene was used to develop novel molecules as a promising new precursor of insecticide.A series of amide-containing derivatives ofβ-pinene were synthesized and *** insecticidal activities of these derivatives against Mythimna separate and Semiaphis heraclei were *** structure characterization results showed that the characterization data of amide-containing derivatives were in full agreement with their proposed *** insecticidal activities evaluation results indicated that amide-containing derivatives exhibited weak insecticidal activity against Mythimna separate,but exhibited moderate to good insecticidal activity against Semiaphis *** testing for 72 h,the corrected mortality against Semiaphis heraclei of compounds 5c,5e,5f,5 h,5j,and 5 m was 100%at 1000 mg/*** structure-activity relationship analysis results showed that the introduction of an amide group into the structure of derivatives improved their insecticidal activity against Semiaphis ***,the amide-containing derivatives containing the F and NO_(2) substituted benzene ring might improve their insecticidal activity against Semiaphis *** study will be helpful for the high value-added utilization of the natural renewable resourceβ-pinene and the development of novel insecticides.

关键词： Turpentine pinene derivative amide insecticidal activity

Lightning electromagnetic field generated by grounding electrode considering soil ionization

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Progress in Natural Science:Materials International 2006年第9期16卷 1002-1006页

作者： ZENG Rong , HE Jinliang, ZHANG Bo and gao yanqing (State Key Laboratory of Power Systems, Department of Electrical Engineering, Tsinghua University, Beijing 100084, China) State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

A circuit model with lumped time-variable parameter is proposed to calculate the transient characteristic of grounding electrode under lightning current, which takes into consideration the dynamic and nonlinear effect of soil ionization around the grounding electrode. The ionization phenomena in the soil are simulated by means of time-variable parameters under appropriate conditions. The generated electromagnetic field in the air is analyzed by using electrical dipole theory and image theory when the lightning current flows into the grounding electrode. The influence of soil ionization on the electromagnetic field is investigated.

关键词： electromagnetic field grounding electrode soil ionization transient characteristic.

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敦煌莫高窟唐前期正卷立体化莲瓣纹样分析

敦煌研究 2021年第4期 59-71页

作者：高晏卿筑波大学人间综合研究科日本东京牡丹江师范学院美术与设计学院黑龙江牡丹江157011

敦煌莫高窟所见正卷立体化莲瓣纹样,以前端作三分弧形且翘起为特征。这种纹样在唐高宗、武则天时期的两京地区极为流行,武周及其以后逐渐减少。而在唐前期的敦煌,正卷立体化莲瓣呈现与两京地区同步发展的态势,自唐前期第二期开始广泛使... 详细信息

敦煌莫高窟所见正卷立体化莲瓣纹样,以前端作三分弧形且翘起为特征。这种纹样在唐高宗、武则天时期的两京地区极为流行,武周及其以后逐渐减少。而在唐前期的敦煌,正卷立体化莲瓣呈现与两京地区同步发展的态势,自唐前期第二期开始广泛使用,进入唐前期第三期后以瓣代花形式不再流行,多作为卷草中的花瓣或草叶表现。

关键词：敦煌莫高窟宝相花卷草正卷立体化莲瓣