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Responses of zonal wind at -40°N to stratospheric sudden warming events in the stratosphere, mesosphere and lower thermosphere

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Science China(Technological Sciences) 2017年第6期60卷 935-945页

作者： YANG JunFeng XIAO CunYing hu Xiong XU QingChen National Space Science Center Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Based on the data at^40°N at different longitudes during different stratospheric sudden warming(SSW)events,the responses of zonal winds in the stratosphere,mesosphere and lower thermosphere to SSWs are studied in this *** variations of zonal wind over Langfang,China(39.4°N,116.7°E)by MF radar and the modern era retrospective-analysis for research and applications(MERRA)wind data during 2010 and 2013 SSW and over Fort Collins,USA(41°N,105°W)by lidar and MERRA wind data during 2009 SSW are *** show that the zonal wind at^40°N indeed respond to the SSWs while different specifics are found in different SSW events or at different *** zonal wind has significant anomalies during the *** Langfang,before the onset of 2010 and 2013 SSW,the zonal wind reverses from eastward to westward below about 60–70 km and accelerates above this region,while westward wind prevails from 30 to 100 km after the onset of2010 SSW,and westward wind prevails in 30–60 and 85–100 km and eastward wind prevails in 60–85 km after the onset of2013 *** Fort Collins during 2009 SSW,eastward wind reverses to westward in 20–30 km before the onset while westward wind prevails in 20–30 and 60–97 km and eastward wind prevails in 30–60 and in 97–100 km after the ***,simulations by the specified dynamics version of the whole atmosphere community climate model(SD-WACCM)are taken to explain different responding specifics of zonal wind to SSW *** is found that the modulation of planetary wave(PW)plays the main *** phases of PWs would lead to the different zonal wind along with longitudes and the different amplitudes and phases in different SSW events can lead to the different zonal wind responses.

关键词： stratospheric sudden warming(SSW) MF radar WACCM planetary waves

Dynamic Performance Investigation of A Spar-Type Floating Wind Turbine Under Different Sea Conditions

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China Ocean Engineering 2018年第3期32卷 256-265页

作者： WANG Han hu Zhi-qiang MENG Xiang-yin State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China School of Engineering Newcastle UniversityNewcastle upon TyneNE1 7RU UK

Both numerical calculation and model test are important techniques to study and forecast the dynamic responses of the floating offshore wind turbine(FOWT). However, both the methods have their own limitations at present. In this study, the dynamic responses of a 5 MW OC3 spar-type floating wind turbine designed for a water depth of 200 m are numerically investigated and validated by a 1:50 scaled model test. Moreover, the discrepancies between the numerical calculations and model tests are obtained and discussed. According to the discussions, it is found that the surge and pitch are coupled with the mooring tensions, but the heave is independent of them. Surge and pitch are mainly induced by wave under wind wave conditions. Wind and current will induce the low-frequency average responses, while wave will induce the fluctuation ranges of the responses. In addition, wave will induce the wavefrequency responses but wind and current will restrain the ranges of the responses.

关键词： spar-type floating wind turbine dynamic response numerical calculation model test time domain analysis frequency domain analysis

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中国体育品牌产业竞争力比较研究

统计与信息论坛 2012年第4期27卷 67-71页

作者：胡效芳焦兵张文彬陕西师范大学体育学院陕西西安710062 西安财经学院经济学院陕西西安710100

根据2008-2010年香港上市的中国六家体育品牌公司三年财务报表数据,运用因子分析法,从变现能力、资产管理能力及盈利能力等六个方面构建了体育品牌产业竞争力评价模型。利用该模型对李宁、安踏、中国动向、匹克、特步以及361度6家在香... 详细信息

根据2008-2010年香港上市的中国六家体育品牌公司三年财务报表数据,运用因子分析法,从变现能力、资产管理能力及盈利能力等六个方面构建了体育品牌产业竞争力评价模型。利用该模型对李宁、安踏、中国动向、匹克、特步以及361度6家在香港上市的中国体育品牌公司产业竞争力进行实证分析,研究发现,虽然中国体育品牌产业竞争力有了很大提升,但是还需要在品牌设计及创新方面进一步努力。

关键词：体育品牌上市公司产业竞争力因子分析法

Asymmetric Polymerization of N-Vinylcarbazole with Optically Active Anionic Initiators

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Chinese Journal of Polymer Science 2015年第11期33卷 1618-1624页

作者： Wei hu 曹靖 Yi-ling huang Sai Liang Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education College of ChemistryXiangtan University

The anionic polymerization of N-vinylcarbazole（NVC） by using optically active anionic initiators such as the lithium salts of（S）-1-（9H-fluoren-2-yl）-4-isopropyl-4,5-dihydrooxazole（（S）-1-FIDH） and（S）-2-（9H-fluoren-2-yl）-4-isopropyl-4,5-dihydrooxazole（（S）-2-FIDH） and complexes of（-）-Sparteine with n-butylithium（n-Bu Li-（-）-Sp） or fluorenyl lithium（FILi-（-）-Sp） was achieved. The yield and specific rotation of poly（N-vinylcarbazole）s（poly（NVC）s） were considerably affected by the molar ratio of（S）-FIDH to NVC. The highest yield and specific rotation were obtained with Li-（S）-1-FIDH as an initiator, with a molar ratio of monomer and initiator [M]/[I] = 10/1. The effects of the chiral initiators, type of solvent and the polymerization temperature were investigated. The obtained optical activity of polymers was attributed to asymmetric induction of the chiral initiators.

关键词： Helical polymer Anionic polymerization Chiral carbon anionic initiator N-vinylcarbazole

The Record-breaking Mei-yu in 2020 and Associated Atmospheric Circulation and Tropical SST Anomalies

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Advances in Atmospheric Sciences 2021年第12期38卷 1980-1993页

作者： Yihui DING Yunyun LIU Zeng-Zhen hu National Climate Center China Meteorological AdministrationBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Climate Prediction Center NCEP/NOAACollege ParkMD 20740USA

The record-breaking mei-yu in the Yangtze-huaihe River valley(YHRV)in 2020 was characterized by an early onset,a delayed retreat,a long duration,a wide meridional rainbelt,abundant precipitation,and frequent heavy rainstorm *** is noted that the East Asian monsoon circulation system presented a significant quasi-biweekly oscillation(QBWO)during the mei-yu season of 2020 that was associated with the onset and retreat of mei-yu,a northward shift and stagnation of the rainbelt,and the occurrence and persistence of heavy rainstorm ***,during the mei-yu season,the monsoon circulation subsystems,including the western Pacific subtropical high(WPSH),the upper-level East Asian westerly jet,and the low-level southwesterly jet,experienced periodic oscillations linked with the *** notably,the repeated establishment of a large southerly center,with relatively stable latitude,led to moisture convergence and ascent which was observed to develop *** was accompanied by a long-term duration of the mei-yu rainfall in the YHRV and frequent occurrences of rainstorm ***,two blocking highs were present in the middle to high latitudes over Eurasia,and a trough along the East Asian coast was also active,which allowed cold air intrusions to move southward through the northwestern and/or northeastern *** cold air frequently merged with the warm and moist air from the low latitudes resulting in low-level convergence over the *** persistent warming in the tropical Indian Ocean is found to be an important external contributor to an EAP/PJ-like teleconnection pattern over East Asia along with an intensified and southerly displaced WPSH,which was observed to be favorable for excessive rainfall over YHRV.

关键词： record-breaking mei-yu western Pacific subtropical high quasi-biweekly oscillation Tropical Indian Ocean warming low-level southwesterly jet blocking high

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超声评估非孕期宫颈机能不全研究进展

中国医学影像技术 2021年第4期37卷 608-611页

作者：吴思婷胡兵三峡大学附属仁和医院超声科湖北宜昌443001

宫颈在妊娠和分娩中发挥关键作用,宫颈机能不全(CIC)可导致女性出现反复流产及早产。孕前评估宫颈机能是可使备孕女性避免不良妊娠结局的重要保障,超声则是评估宫颈机能不全的常用方法。本文对超声评估非孕期宫颈机能不全研究进展进行... 详细信息

宫颈在妊娠和分娩中发挥关键作用,宫颈机能不全(CIC)可导致女性出现反复流产及早产。孕前评估宫颈机能是可使备孕女性避免不良妊娠结局的重要保障,超声则是评估宫颈机能不全的常用方法。本文对超声评估非孕期宫颈机能不全研究进展进行综述。

关键词：宫颈疾病超声检查机能不全非孕期

Antimicrobial resistance and molecular epidemiological characteristics of clinical isolates of Staphylococcus aureus in Changsha area

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Chinese Medical Journal 2012年第13期125卷 2289-2294页

作者： ZOU Ming-xiang ZHOU Rong-rong WU wen-jun ZHANG Ning-jie LIU wen-en hu Fu-ping FAN Xue-gong Department of Clinical LaboratoryXiangya Hospital Central South University ChangshaHunan 410008 China Department of Infectious DiseasesXiangya Hospital Central South University ChangshaHunan 410008 China Institute of Antibiotics Huashan Hospital Fudan UniversityShanghai 200040 China

Background Increasing prevalence of Staphylococcus aureus （S. aureus）, particularly methicillin-resistant S. aureus （MRSA） has been reported in China. In this study, we investigated the drug resistance characteristic, genetic background, and molecular epidemiological characteristic of S. aureus in Changsha. Methods Between January 2006 and December 2008, 293 clinical isolates of S. aureus were collected from 11 hospitals in Changsha and identified by the Vitek-2 system. All the isolates were verified as MRSA by PCR amplification of both femA and mecA genes. K-B disk method was used to test drug sensitivity of S. aureus to antibiotics. Pulsed-field gel electrophoresis （PFGE） was performed for genotypic and homologous analysis of 115 isolates randomly selected from the original 293 clinical S. aureus isolates. Results S. aureus was highly resistant to penicillin, ampicillin, erythromycin, and clindamycin with resistant rates of 96.6%, 96.6%, 77.1%, and 67.2% respectively. All the isolates were susceptible to tecoplanin, vancomycin, and linezolid. MRSA accounted for 64.8% （190/293） of all the S. aureus strains. The 115 S. aureus isolates were clustered into 39 PFGE types by PFGE typing, with 13 predominant patterns （designated types A to M） accounting for 89 isolates. The most prevalent PFGE type was type A （n=56, 48.7%） and 100.0% of type A strains were MRSA. PFGE type A included 13 subtypes, and the most prevalent subtype was subtype A1 （46.4%, 26/56）. Strains with PFGE type A were isolated from eight hospitals （8/11）, and both subtypes A1 and A4 strains were isolated in a university hospital. Conclusions Clinical isolates of S. aureus in Changsha were resistant to multiple traditional antibiotics. There was an outbreak of PFGE type A MRSA in this area and the A1 subtype was the predominant epidemic clone. Dissemination of the same clone was an important reason for the wide spread of MRSA.

关键词： staphylococcus aureus antimicrobial resistance pulsed-field gel electrophoresis molecular epidemiological characteristics

A Hybrid Cellular Swarm Optimization Method for Traffic-Light Scheduling

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Chinese Journal of Electronics 2018年第3期27卷 611-616页

作者： hu wenbin WANG huan YAN Liping DU Bo School of Computer Wuhan University

With increasing traffic every day, most cities in the world are facing serious traffic problems, such as traffic accidents, congestion and air pollution. Despite the recent improvement of urban infrastructure, reasonable traffic light scheduling still plays an important role in alleviating these traffic problems. It is a great challenge to schedule a huge number of traffic lights efficiently. To solve this problem, we propose a Hybrid cellular swarm optimization method(HCSO) to optimize the scheduling of urban traffic lights. HCSO achieves an efficient and flexible scheduling, which includes the phase timing scheduling and the phase shifting scheduling. To formulate effective solutions for various traffic problems and achieve a globally dynamic scheduling, flexible and concise transition rules based on Cellular automaton(CA) are *** the Dynamic cellular particle swarm optimization algorithm(DCPSO) is proposed to find the optimal phase timing scheduling efficiently. Moreover, compared with the differential search algorithm method, the genetic algorithm method, the particle swarm optimization method, the comprehensive learning particle swarm optimization method and the random method in real cases, extensive experiments reveal that HCSO achieves obvious improvements under different traffic conditions.

关键词： Transition rules Phase timing scheduling Phase shifting scheduling

A novel technique for probing phase transitions in ferroelectric functional materials: Condensed matter spectroscopy

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Science China(Technological Sciences) 2016年第10期59卷 1537-1548页

作者： ZHANG JinZhong JIANG Kai hu ZhiGao Chu JunHao Department of Electronic Engineering East China Normal University

As relaxor ferroelectric functional materials, their crystal structures depend on temperature, component, electric filed, pressure, and so on, which are important for the applications of sensors, transducers, and actuators. For the case of PbTiO3-based ferroelectrics Pb（Zn2/3Nb2/3）O3-PbTiO3, Pb（Mg1/3Nb2/3）O3-PbTiO3, Pb（In1/2Nb1/2）O3-Pb（Mgu3Nb2/3）O3-PbTiO3 and some other crystals, they have been extensively investigated due to the excellent electromechanical and piezoelectric properties. Generally, ferroelectric crystal structure and corresponding phase diagram are detected by temperature-dependent high resolution X-ray diffraction, low frequency dielectric permittivity, and domain structures. In this review, we focus on the novel condensed matter spectroscopy （i.e., spectroscopic ellipsometry, transmittance, photoluminescence spectra as well as Raman spectra）, which is nondestructive, noncontact, and sensitive optical techniques for probing symmetries, phase transitions and phase diagrams of ferroelectric crystals. Besides, it can supply some other physical and chemical information for ferroelectric and semiconductor functional materials such as optical band gap, electronic transitions, dielectric functions, optical conductivity, absorption, pho- non modes, lattice dynamics as functions of temperature and PT composition.

关键词： ferroelectrics phase diagram Raman scattering ellipsometric spectroscopy transmittance photoluminescence