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Analysis of the Mechanism Underlying Tibetan Plateau Vortex Frequency Difference between Strong and Weak MJO Periods

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Journal of Meteorological Research 2017年第3期31卷 530-539页

作者： guoping li Fuhu ZHAO School of Atmospheric Sciences Chengdu University of Information Technology Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Chongqing Meteorological Observatory

In this paper, the NCEP/DOE reanalysis data, OLR data from NOAA, Australian Meteorological Bureau real-time multivariate MJO index, and Tibetan Plateau vortex （TPV） statistical data from the Chengdu Institute of Plateau Met- eorology, are used to discuss the modulation of the TPV by the MJO, through applying the wavelet analysis and com- posite analysis. The results show that：（1） The MJO plays an important role in modulating the TPV, as the number of TPVs generated in strong MJO periods is three times that in weak periods. （2） During strong （weak） MJO periods, the Tibetan Plateau （TP） is in control of a low-frequency, low-pressure cyclone （high-pressure, anticyclone） system, and thus the atmospheric circulation conditions over the plateau are conducive （inconducive） to the generation of TPVs. （3） During strong （weak） MJO periods, southerly （northerly） winds prevail in the east of the TP, while north- erly （southerly） winds in the west. Over the northern part of the TP, easterly （westerly） flow is predominant, while westerly （easterly） flow prevails over the south, thus conducive （inconducive） to the formation of cyclonic circula- tion （i.e., TPVs） at low altitude over the TP. （4） In strong MJO periods, water vapor is relatively less abundant over most of the TP, inconducive to the generation of TPVs; however, moisture transported by the south branch trough and the low-frequency, high-pressure anticyclone system from the Bay of Bengal, are very important for the develop- ment of TPVs. As the strength of the MJO changes continuously during its eastward propagation, the inten- sity of tropical convection and vertical circulation structures of the tropical atmosphere also change accordingly. Al- ternation between favorable and unfavorable conditions for the generation of TPVs occurs, thus resulting in signifi- cant frequency differences of TPVs between strong and weak MJO periods.

关键词： Tibetan Plateau vortex MJO modulation real-time multivariate MJO index composite analysis

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Empirical Study on Effect of Industrial Structure Change on Regional Economic Growth of Beijing-Tianjin-Hebei Metropolitan Region

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Chinese Geographical Science 2011年第6期21卷 708-714页

作者： CHEN Hongxia li guoping School of Government Central University of Finance and Economics Beifing 100081 China School of Government Peking University Beijing 100871 China

Based on the data of gross domestic product(GDP),industrial added value and the proportion of industrial employees from 2000 to 2008,this paper studies the effect of industrial structure change on the regional economic growth of Beijing-Tianjin-Hebei Metropolitan Region in China using the shift-share *** results show that:1) In the 21st century,the industrial output of three industries,namely,primary,secondary,and tertiary,and the GDP grew rapidly in the study *** tertiary industry grew the fastest;it had the largest contribution to the GDP and mean-while had become the most competitive industry in the metropolitan region.2) The development of cities within the region was not ***,compared with Tianjin,Beijing,as one of the two core cities,was more rational in the industrial ***,the surrounding eight cities,which are Shijiazhuang,Qinhuangdao,Tangshan,Langfang,Baoding,Cangzhou,Zhangjiakou,and Chengde,were all uncompetitive than the two core cities.3) There was a great industrial gradient in the region(especially between the two core cities and the cities of Tangshan,Baoding,Zhangjia-kou,Chengde,Cangzhou,and Langfang).As a result,it is foreseeable that the industry transfer in the Bei-jing-Tianjin-Hebei Metropolitan Region will be one of the trends in regional development,and the industry transfer is inevitably to promote the regional integration.

关键词： Beijing-Tianjin-Hebei Metropolitan Region economic growth shift-share analysis industrial structure

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Fluorescent traceable nanoparticles by co-self-assembly of carbon dot-drug conjugate and biodegradable hyperbranched polymer for diagnosis and therapy

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Particuology 2022年第3期20卷 79-87页

作者： guoping li Mingliang Pei Xinming li Peng liu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Carbon dots(CDs)have attracted more interest in tumor theranostics,but they suffer from the rapid renal clearance due to small size and high *** solve such problems,hydrophobic pH-triggered carbon dot-drug conjugate(CDs-Hy-DOX)with high doxorubicin(DOX)content of 48.23%were designed by covalent conjugation of DOX onto the CDs via acid-labile linkage with hydrazine(Hy)as *** the fluorescent traceable hybrid prodrug nanoparticles were fabricated via co-self-assembly with the CDs-Hy-DOX as pH-sensitive prodrug and a pH/reduction dual-triggered degradable hyperbranched polymer PEG-PO-Cy as polyethylene glycol(PEG)-based surfactant,as well as gatekeeper for pH/reduction dual-triggered DOX *** hybrid prodrug nanoparticles with hydrodynamic diameter of 220 nm and DOX content of 22.99%were obtained with the optimized co-self-assembling *** could release 68.98%of DOX in the simulated tumor microenvironment within 3 days in a sustained release mode,with a premature drug leakage of 7.58%.After the acid-triggered DOX release from the CDs-Hy-DOX,which was accelerated by the pH/reduction dual-triggered degradation of the hyperbranched polymer,the strong fluorescence of CDs-Hy was recovered,demonstrating the promising potential in future tumor nanotheranostics.

关键词： Tumor nanotheranostics Carbon dots Hyperbranched polymer Tumor-specific Fluorescent imaging

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Impact of Regional Development on Carbon Emission: Empirical Evidence Across Countries

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Chinese Geographical Science 2014年第5期24卷 499-510页

作者： li guoping YUAN Yuan School of Government Peking University

Global warming is recently an urgent issue worldwide. The increase of carbon emissions induced by human economic activi- ties has become a major driving force behind global climate change. Thus, as a matter of social responsibility, reasonable carbon con- straints should be implemented to ensure environmental security and sustainable development for every country. Based on a summary of studies that examined the relationship between carbon emissions and regional development, this paper shows that human activity-led carbon emission is caused by the combination of several influencing factors, including population size, income level, and technical pro- gress. Thus, a quantitative model derived from IPAT-ImPACT-Kaya series and STIRPAT models was established. Empirical analysis using multivariate nonlinear regression demonstrated that the origins of growing global carbon emission included the increasing influ- encing elasticity of the population size and the declining negative effect of technical progress. Meanwhile, in context of classification of country groups at different income levels, according to the comparison of fluctuating patterns of the influencing elasticity, technical progress was found as the main factor influencing carbon emission levels in high-income countries, and population size might he the controlling factor in middle-income countries. However, for low-income countries, the nonlinear relationship between carbon emission and its influencing factors was not significant, whereas population growth was identified as an important potential driving force in future carbon emissions. This study can therefore provide a reference for the formulation of policies on carbon constraints, especially to de- velop more efficient carbon mitigating policies for countries at different income levels.

关键词： carbon emission regional development population size income level technical progress

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Dynamic and Numerical Study of Waves in the Tibetan Plateau Vortex

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Advances in Atmospheric Sciences 2014年第1期31卷 131-138页

作者： CHEN Gong li guoping Institute of Plateau Meteorology China Meteorological Administration College of Atmospheric Sciences Chengdu University of Information Technology and The Key Laboratory of Plateau Atmosphere and Environment of Sichuan Province

In terms of its dynamics, The Tibetan Plateau Vortex （TPV） is assumed to be a vortex in the botmdary layer forced by diabatic heating and friction. In order to analyze the basic characteristics of waves in the vortex, the governing equations for the vortex were established in column coordinates with the balance of gradient wind. Based on this, the type of mixed waves and their dispersion characteristics were deduced by solving the linear model. Two numerical simulations with triple-nested domains--one idealized large-eddy simulation and one of a TPV that took place on 14 August 2006---were also carried out. The aim of the simulations was to validate the mixed wave deduced from the governing equations. The high-resolution model output data were analyzed and the results showed that the tangential flow field of the TPV in the form of center heating was cyclonic and convergent in the lower levels and anticyclonic and divergent in the upper levels. The simulations also showed that the vorticity of the vortex is uneven and might have shear flow along the radial direction. The changing vorticity causes the formation and spreading of vortex Rossby （VR） waves, and divergence will cause changes to the n^otion of the excitation and evolution of inertial gravity （IG） waves. Therefore, the vortex may contain what we call mixed ：inertial gravity-vortex Rossby （IG-VR） waves. It is suggested that some strongly developed TPVs should be studied in the future, because of their effects on weather in downstream areas.

关键词： Tibetan Plateau Vortex thermal forcing tangential flow field mixed inertial gravity-vortex Rossby waves

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Dynamics and control of variable geometry truss manipulator

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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 243-262页

作者： Xiaofeng liU Qishuai WANG Haiquan li guoping CAI Department of Engineering Mechanics State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

Variable geometry truss manipulator （VGTM） has potential to work in the future space applications, of which a dynamic model is important to dynamic analysis and control of the system. In this paper, an approach is presented to model the dynamic equations of a VGTM by independent variables, which consists of two double-octahedral truss units and a 3-revolute-prismatic-spherical （3-RPS） parallel manipulator. In this ap- proach, the kinematic recursive relations of two adjacent bodies and geometric constrains are used to deduce the kinematic equations of the VGTM, and Jourdain＇s velocity varia- tion principle is adopted to establish the dynamic equations of the system. The validity of the proposed dynamic model is verified by comparison of numerical simulations with the software ADAMS. Besides, an active controller for trajectory tracking of the system is designed by the computed torque method. The effectiveness of the controller is numer- ically proved.

关键词： variable geometry truss manipulator (VGTM) double-octahedral truss unit,3-revolute-prismatic-spherical (3-RPS) parallel manipulator dynamic modeling activecontrol

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Fourth Industrial Revolution:Technological Drivers,Impacts and Coping Methods

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Chinese Geographical Science 2017年第4期27卷 626-637页

作者： li guoping HOU Yun WU Aizhi School of Government Peking UniversityBeijing 100871China NUS Business School National University of SingaporeSingapore 117592Singapore library Peking UniversityBeijing 100871China

The world is marching into a new development period when the digital technology,physical technology,and biological technology have achieved an unprecedented development respectively in their own fields,and at the same time their applications are converging *** are the three major technological drivers for the Fourth Industrial *** paper discusses the specific technology niches of each kind technological driver behind the Fourth Industrial Revolution,and then evaluates impacts of the Fourth Industrial Revolution on global industrial,economic,and social *** last this paper proposes possible measures and policies for both firms and governments to cope with the changes brought by the Fourth Industrial Revolution.

关键词： Fourth Industrial Revolution technological drivers global impacts firm-level adjustments government policies

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面向多峰函数优化的PASFli算法及应用

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计算机工程与应用 2013年第21期49卷 199-203,229页

作者：李国平湖南工学院湖南衡阳421002

针对基本混合蛙跳算法在高维多峰函数优化时早熟及难以找到所有全局极值的问题,提出了一种具有混合智能的多态子种群自适应混合蛙跳免疫算法,证明了算法以概率1收敛于全局最优解。该算法采用双层进化模式,融合了混合蛙跳、免疫克隆选择... 详细信息

针对基本混合蛙跳算法在高维多峰函数优化时早熟及难以找到所有全局极值的问题,提出了一种具有混合智能的多态子种群自适应混合蛙跳免疫算法,证明了算法以概率1收敛于全局最优解。该算法采用双层进化模式,融合了混合蛙跳、免疫克隆选择技术。在低层混合蛙跳操作中,加入了多态自适应子种群机制,提高了子种群多样性,有效抑制了早熟现象;在算法进化后期,提出了全局极值筛选策略,将子种群极值点提升到高层免疫克隆选择操作,进一步提高了全局寻优能力。通过复杂多峰函数仿真实验,表明该算法能够快速有效地给出全部全局最优解。

关键词：混合蛙跳算法免疫算法自适应函数优化

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Analysis of a Vortex Precipitation Event over Southwest China Using AIRS and In Situ Measurements

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Advances in Atmospheric Sciences 2017年第4期34卷 559-570页

作者： Chengcheng NI guoping li Xiaozhen XIONG School of Atmospheric Sciences Chengdu University of Information Technology Meteorological Observatory Chengdu Meteorological Bureau Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Centre of Satellite Application and Research NOAACollege Park

A strong precipitation event caused by the southwest vortex（SWV）, which affected Sichuan Province and Chongqing municipality in Southwest China on 10–14 July 2012, is investigated. The SWV is examined using satellite observations from AIRS（Atmospheric Infrared Sounder）, in situ measurements from the SWV intensive observation campaign, and MICAPS（Marine Interactive Computer-Aided Provisioning System） data. Analysis of this precipitation process revealed that：（1）heavy rain occurred during the development phase, and cloud water content increased significantly after the dissipation of the SWV;（2） the area with low outgoing longwave radiation values from AIRS correlated well with the SWV;（3） variation of the temperature of brightness blackbody（TBB） from AIRS reflected the evolution of the SWV, and the values of TBB reduced significantly during the SWV＇s development; and（4） strong temperature and water vapor inversions were noted during the development of the SWV. The moisture profile displayed large vertical variation during the SWV＇s puissant phase,with the moisture inversion occurring at low levels. The moisture content during the receding phase was significantly reduced compared with that during the developing and puissant phases. The vertical flux of vapor divergence explained the variation of the moisture profile. These results also indicate the potential for using AIRS products in studying severe weather over the Tibetan Plateau and its surroundings, where in situ measurements are sparse.

关键词： precipitation event AIRS southwest vortex temperature profile moisture profile

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基于考古发现谈晋唐时期新疆饮食文化——以阿斯塔那古墓为例

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四川旅游学院学报 2025年第1期 1-7页

作者：张诗瑶李国平塔里木大学历史与哲学学院新疆阿拉尔843300

新疆自古以来族群活动频繁,又因古丝绸之路成为东西方文化交流的中心,这促成当地文化的多样性。新疆阿斯塔那墓地出土了晋唐时期与饮食有关的诸多器物,展现了晋唐时期新疆民众的生活方式和饮食习惯,既是晋唐时期新疆地区社会发展与经济... 详细信息

新疆自古以来族群活动频繁,又因古丝绸之路成为东西方文化交流的中心,这促成当地文化的多样性。新疆阿斯塔那墓地出土了晋唐时期与饮食有关的诸多器物,展现了晋唐时期新疆民众的生活方式和饮食习惯,既是晋唐时期新疆地区社会发展与经济繁荣的直接体现,更呈现了晋唐时期丝绸之路文化交流的重要影响。研究基于历史文物的信息记载功能,为学界展示晋唐新疆的历史发展及丝绸之路的意义与价值。

关键词：新疆晋唐时期饮食文化阿斯塔那墓地

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