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Seasonal variability in tropical and subtropical convective and stratiform precipitation of the East Asian monsoon

Science China Earth Sciences 2011年第10期54卷 1595-1603页

作者： HU liang li yaodong SONG Yang DENG DiFei National Satellite Meteorological Center China Meteorological Administration Beijing 100081 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Beijing Aviation Meteorological Institute Beijing 100085 China L M. Systems Group Satellite Meteorology and Climatology Division National Oceanic andAtmospheric Administration Washington D C USA

Seasonal variations in tropical and subtropical convective and stratiform precipitation of the East Asian monsoon are analyzed using 10-year (1998-2007) Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) rain products (2A25). Datasets from the Intergovernmental Panel on Climate Change Fourth Assessment Report (AR4) 24 general circulation models (GCMs) are evaluated using TRMM PR rain products in terms of their ability to simulate convective and stratiform precipitation and their deficiencies. The results show that Asian monsoon convective and stratiform precipitation increases significantly after onset of the summer monsoon, but the percentage of convective precipitation clearly decreases over tropical areas while it increases in subtropical regions. The GCMs simulate well the seasonal variation in the contribution of Asian monsoon subtropical convective precipitation to the total rainfall; however, the simulated convective precipitation amount is high while the simulated stratiform precipitation amount is low relative to TRMM measurements, especially over the Asian monsoon tropical region. There is simultaneous TRMM-observed convective and stratiform precipitation in space and time, but GCMs cannot simulate this relationship between convective and stratiform precipitation, resulting in the deficiency of stratiform precipitation simulations.

关键词： convective precipitation stratiform precipitation Asian monsoon seasonal variability

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A comparison study of summer-time synoptic-scale waves in South China and the Yangtze River basin using the TRMM Multi-Satellite Precipitation Analysis daily product

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Science China Earth Sciences 2008年第1期51卷 114-122页

作者： Fu Rong Hu liang Gu GuoJun li yaodong Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA 30332 USA Goddard Earth Sciences and Technology Center University of

Summer-time synoptic-scale waves in South China and the Yangtze River basin are quantified and compared by means of analyzing the 6-year (1998–2004) TRMM Multi-Satellite Precipitation Analysis (TMPA) daily product. A... 详细信息

关键词： TRMM 3-dimensional spectrum analysis synoptic-scale waves South China Yangtze River basin

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Simulation of FY-2D infrared brightness temperature and sensitivity analysis to the errors of WRF simulated cloud variables

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Science China Earth Sciences 2018年第7期61卷 957-972页

作者： Xiaokang SHI yaodong li Jianwen liU Xizi XIANG Le liU Beijing Aviation Meteorological Institute Beijing 100085China Guizhou Sub-bureau of Southwest Air Traffic Management Bureau of Civil Aviation of China Guiyang 550002China Guangxi Meteorological Observatory Nanning 530022China

This study simulated FY-2 D satellite infrared brightness images based on the WRF and RTTOV models. The effects of prediction errors in WRF micro-and macroscale cloud variables on FY-2 D infrared brightness temperature accuracy were analyzed. The principle findings were as follows. In the T+0–48 h simulation time, the root mean square errors of the simulated brightness temperatures were within the range 10–27 K, i.e., better than the range of 20–40 K achieved previously. In the T+0–24 h simulation time, the correlation coefficients between the simulated and measured brightness temperatures for all four channels were >0.5. The simulation performance of water channel IR3 was stable and the best. The four types of cloud microphysical scheme considered all showed that the simulated values of brightness temperature in clouds were too high and that the distributions of cloud systems were incomplete, especially in typhoon areas. The performance of the THOM scheme was considered best, followed in descending order by the WSM6, WDM6, and liN schemes. Compared with observed values, the maximum deviation appeared in the range 253–273 K for all schemes. On the microscale, the snow water mixing ratio of the THOM scheme was much bigger than that of the other schemes. Improving the production efficiency or increasing the availability of solid water in the cloud microphysical scheme would provide slight benefit for brightness temperature simulations. On the macroscale, the cloud amount obtained by the scheme used in this study was small. Improving the diagnostic scheme for cloud amount, especially high-level cloud, could improve the accuracy of brightness temperature simulations. These results could provide an intuitive reference for forecasters and constitute technical support for the creation of simulated brightness temperature images for the FY-4 satellite.

关键词： FY-2D RTTOV WRF Simulated brightness temperature Cloud amount Cloud microphysics scheme TyphoonMatmo

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2,5-Dialkoxylphenyl-l,3,4-oxadiazoles as efficient organogelators and their self-assembling property

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Frontiers of Chemical Science and Engineering 2014年第2期8卷 219-224页

作者： Zipei SUN Xuelin DONG Yan ZHAI Ziyan li yaodong HUANG Key Laboratory of Systems Bioengineering (Ministry of Education) School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Four 2,5-dialkoxylphenyl-l,3,4-oxadiazoles are shown to be efficient organogelators. These com- pounds readily form stable gels in many organic solvents and their gelation property as well as supramolecular structures were investigated by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, 1H nuclear magnetic resonance （1H NMR）, and ultraviolet-visible spectroscopy （UV-vis）. The results indicate that the gelator molecules self-assemble into gels with elongated fibrous networks and layer structures, and van der Waals interaction is the main driving force.

关键词： 1,3,4-oxadiazoles organogelator selfassembly

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Application and improvement of an adaptive ensemble Kalman filter for soil moisture data assimilation

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Science China Earth Sciences 2010年第11期53卷 1700-1708页

作者： Shi XiaoKang Wen Jun liu JianWen Tian Hui Wang Xin li yaodong Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lab Climate Environm & Disasters Western China Lanzhou 730000 Peoples R China Beijing Aviat Meteorol Inst Beijing 100085 Peoples R China

Accurate assignment of model and observation errors is crucial for the successful application of land surface data assimilation algorithms. Poorly-specified model and observation errors can significantly degrade assimilation results. In 2008, Reichle et al. developed an operational procedure to adaptively tune model and observation errors. In this paper, we modified and applied Reichle's procedure in the Noah land surface model to assimilate observed surface soil moisture data. Numerical simulations showed that: (1) the best estimate of model and observation errors appears when the empirical factor β equals 1.02; (2) the Reichle procedure can be deployed to adaptively tune errors if their true values change slowly; and (3) convergence of the Reichle procedure was improved using better initial errors achieved by iterative computations.

关键词： Noah numerical simulation data assimilation adaptive ensemble Kalman filter soil moisture

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Improved SAL method and its application to verifying regional soil moisture forecasting

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Science China Earth Sciences 2014年第9期57卷 2657-2670页

作者： SHI XiaoKang liU JianWen li yaodong TIAN Hui liU XiangPei Beijing Aviation Meteorological Institute Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Chinese Academy Sciences Institute of Meteorology and Oceanography PLA University of Science and Technology

The regional verification of soil moisture is a vital step in evaluating and improving numerical model performance and utilizing forecast results. Currently, even with improved spatial and temporal resolutions of numerical model, verification methods for soil moisture data still rely on the traditional intensity verification parameters, such as mean error(ME) and root-mean-squared error(RMSE). Those methods provide only incomplete and sometimes inaccurate messages and thus hinder a proper evaluation of a forecast model. The SAL method is an object-based regional verification method with respect to precipitation forecasts. Based on the SAL method, a novel object-based method(SAL-DN) is proposed here, which can be used to test regional soil moisture. Both the ideal experiment and real experiment show that the SAL-DN method can reveal the differences between the observed and forecast soil moisture in three aspects: structure, amplitude, and location, and the results can reflect the actual situation. Furthermore, compared with the SAL method, the SAL-DN method is also capable of verifying physical quantities with high-value and low-value centers like temperature. Therefore, the SAL-DN method enhances verification accuracy and can be applied widely.

关键词： soil moisture numerical simulation regional verification SAL-DN

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Diagnostic Analysis of a Rainstorm Process in Chongqing

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Meteorological and Environmental Research 2014年第1期5卷 28-35页

作者： Hu Rong Shi Xiaokang li yaodong Institute of Meteorology and Oceanography PLA University of Science and Technology Beijing Aviation Meteorological Institute

[Objective] The research aimed to analyze a rainstorm process in Chongqing. [Methed] Based on precipitation product datasets and NCEP reanalysis data, synoptic situation and diagnostic analysis of a heavy rain process during 11 -12 May, 2012 in Chongqing were made, and the diagnostic analysis included dynamic and vapor conditions, instability index, vapor helicity and vapor divergence flux. [ Result] The east-south moving short wave trough and east-north moving southwest vortex were the main synoptic systems causing the heavy rain; the positive vorticity advection before trough and after ridge helped the ascending motion from surface; the southwest stream at 700 hPa provided vapor and energy, promoting and maintaining the intense development of convection; the higher vapor helicity and lower vapor divergence flux were well corresponding with higher precipitation area, and had well temporal correlation, which was significant for forecast of precipitation area and its development; the ascended warm wet stream on the lower air came across the cold air on the upper air, triggering the heavy rain; the Kindex and A index were significant for the heavy rain forecasting. [ Conclusion] The research could provide some references for research and forecast of future rainstorm process in Sichuan and Chongqing.

关键词： Rainstorm Diagnostic analysis Vapor helicity Vapor divergence flux China

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模态声发射技术在构件疲劳裂纹检测中的应用

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振动与冲击 2005年第2期24卷 122-125页

作者：李耀东黄成祥侯力四川大学制造学院成都610065

疲劳裂纹的萌生和扩展是机械零件在变载荷作用下的主要失效形式,在变载荷下出现疲劳裂纹的同时往往伴随着弹性波的扩散,以迅速释放其内部积累的应变能。使用近几年来得到迅速发展的模态声发射技术真实地获取疲劳裂纹的声发射波形,使接... 详细信息

疲劳裂纹的萌生和扩展是机械零件在变载荷作用下的主要失效形式,在变载荷下出现疲劳裂纹的同时往往伴随着弹性波的扩散,以迅速释放其内部积累的应变能。使用近几年来得到迅速发展的模态声发射技术真实地获取疲劳裂纹的声发射波形,使接收到的声发射信号较完整地反映了声发射源的物理状态。在波形分析中采用参数分析法提取声发射波形特征,建立模态声发射参数和裂纹扩展速度之间的数学关系。由于综合采用了多种技术的优点进行信号分析、处理,因此根据声发射信号特征得到的结果将更加逼近实际状态。

关键词：疲劳裂纹模态声发射参数分析

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Exploration of the Integration of Curriculum Ideology and Politics into the Educational Pathway of Standardized Training for General Practice Residents

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Journal of Contemporary Educational Research 2024年第5期8卷 91-96页

作者： Zhuan Huang yaodong li lina Ma Rui Xu Fang Yang Yingpeng Shi Junlin liu The First Affiliated Hospital of Xi’an Medical University Xi’an 710077Shaanxi ProvinceChina School of Foreign Languages Xi’an Medical UniversityXi’an 710077Shaanxi ProvinceChina

In recent years,the national higher education reform has proposed the concept of curriculum ideological and political education as a major *** integration into the standardized training of general practice residents(commonly referred to as general resident training)is an unavoidable trend in the teaching *** on the actual situation of our unit at The First Affiliated Hospital of Xi’an Medical University,this paper emphasizes the necessity of incorporating ideological and political education into the general resident training curriculum,despite the absence of pertinent practical experience in how to effectively incorporate such courses into comprehensive residential *** our hospital,we must assess the ideological and political education in the curriculum of general resident training,proposing a scientific,reasonable ideological and political education concept system for general practice courses,integrating ideological and political education with general practice resident training,and strengthening the team of ideological and political education physicians to teach them to carry out such education,this would foster enthusiasm and *** admission education and training for general practice resident training,as well as regularly hosting symposiums to share ideas and understand the mission of doctors can provide effective experience for ideological and political education in general resident training courses.

关键词： Curriculum ideological and political education General practice General practice residents Standardized training Education path Exploration

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新型三线圈磁耦合谐振式无线电能传输系统及其优化

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高电压技术 2019年第4期45卷 1146-1152页

作者：张黎方胜伟李要东赵彤邹亮山东大学电气工程学院济南250061

为了提高无线电能传输系统效率,提出了新型三线圈磁耦合谐振式无线电能传输系统。首先分析了新型三线圈无线电能传输系统传输效率的数学表达式,得出影响传输效率的重要参数—传输距离、频率、负载,针对各个参数,与传统系统传输效率分别... 详细信息

为了提高无线电能传输系统效率,提出了新型三线圈磁耦合谐振式无线电能传输系统。首先分析了新型三线圈无线电能传输系统传输效率的数学表达式,得出影响传输效率的重要参数—传输距离、频率、负载,针对各个参数,与传统系统传输效率分别进行分析对比;针对3个参数,运用混沌粒子群优化算法进行系统优化,得到传输效率最高时对应的最优参数;最后,为验证理论分析正确性,搭建实验平台,进行实验分析和优化验证。实验结果表明,新型三线圈磁耦合谐振式无线电能传输系统具有更高的传输效率。

关键词：新型三线圈无线电能传输混沌粒子群优化效率优化

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