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风力发电机接闪系统失效风险定量评估方法研究

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中国电机工程学报 2019年第12期39卷 3551-3560页

作者：于万水李庆民张敏昊郭子炘刘亮 Siew Wah Hoon 王健电力系统国家重点实验室(华北电力大学) 北京市昌平区102206 国网冀北电力有限公司电力科学研究院北京市西城区100045 思克莱德大学 Glasgow G1 1XQ UK

雷害问题严重影响风机的正常运行,但针对风机接闪系统的失效风险,目前鲜有定量的分析和评估方法。基于先导发展物理模型,提出风机接闪系统雷击屏蔽失效率的定义和计算方法,并通过叶片雷击模拟实验验证了方法的有效性。比较分析了不同接... 详细信息

雷害问题严重影响风机的正常运行,但针对风机接闪系统的失效风险,目前鲜有定量的分析和评估方法。基于先导发展物理模型,提出风机接闪系统雷击屏蔽失效率的定义和计算方法,并通过叶片雷击模拟实验验证了方法的有效性。比较分析了不同接闪系统型式叶片的雷击屏蔽失效率,并考虑了风机旋转角度和海洋盐雾附着对雷击屏蔽失效率的影响。分析表明,相比于接闪器–引下线结构型式和叶尖包覆铜网型式,采用主梁包覆铜网型式的叶片雷击屏蔽失效率最小,但综合考虑经济性和易维护性,推荐采用叶尖包覆铜网的接闪系统型式。提出的定量分析方法可为风机叶片接闪系统的优化设计和失效风险评估提供依据。

关键词：雷击屏蔽失效率风力发电机接闪系统盐雾附着长间隙放电

Skeleton Keypoints Extraction Method Combined with Object Detection

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Journal of New Media 2022年第2期4卷 97-106页

作者： Jiabao Shi Zhao Qiu Tao Chen Jiale Lin Hancheng Huang Yunlong He d Yu Yang Hainan University HaiKou570228China University College London Gower StreetLondon WC1E 6BTUK Hainan Century Network Security Information Technology Co. Ltd.HaiKou570000China

Big data is a comprehensive result of the development of the Internet of Things and information *** vision requires a lot of data as the basis for *** skeleton data can adapt well to dynamic environment and complex background,it is used in action recognition *** recent years,skeleton-based action recognition has received more and more attention in the field of computer ***,the keypoints of human skeletons are essential for describing the pose estimation of human and predicting the action recognition of the *** paper proposes a skeleton point extraction method combined with object detection,which can focus on the extraction of skeleton *** a large number of experiments,our model can be combined with object detection for skeleton points extraction,and the detection efficiency is improved.

关键词： Big data object decetion skeleton keypoints lightweight openpose

SEMiX and SKYPER an Intelligent IGBT Module with Adaptable Driver

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电力电子 2004年第5期2卷 24-29页

作者： MartinFreyberg MarkusHermwille uk-SongHong JensLi SemikronInternationalDr.FritzMartinGmbh&Co.KGSigmundstr.200.90431Nuremberg.Germany SemikronCo.ltd.137-7.Sosahon-3Dong.Sosa-BuBucheon-City.422-233

Modern power converter designs need compact IGBT modules with simple interfaces for costefficient power *** overall *** AC and DC terminals on eaeh side,driver access on top are recent market requirements for modern power *** leads to the birth of SEMiX-a module platform with the right answer to these *** paper highlights also a new driver solution for modules-SKYPER-a simple add-on gate driver with basic driving and protection *** adaptation to modules-in this article through an example with SEMiX-is tested *** and SKYPER behave like an IPM but offer more flexibilitv to control switching *** a convenient building block for modular inverter solutions.

关键词：逆变器 IGBT模型自适应驱动器 SEMiX SKYPER

一种应用于冬奥会中的低碳CO_(2)冰场技术

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Science Bulletin 2023年第23期68卷 2877-2880页

作者：李力耕刘楷田华蔡金文 Christos N Markides 王竞宇石凌峰王轩马一太梁兴雨舒歌群 State Key Laboratory of Engines Tianjin University AST Refrigeration and Solar Technology(Beijing)Co. Ltd. Department of Chemical Engineering Imperial College London Department of Thermal Science and Energy Engineering University of Science and Technology of China

The issue of climate change is among the most difficult environmental problems faced by human beings[1]and affects all social aspects of human *** 2015,the Paris Agreement set the goal of reducing global greenhouse ga... 详细信息

关键词：冬奥会 limit greenhouse

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干辣椒风味物质气相色谱及质谱方法的研究

辣椒杂志 2007年第1期5卷 41-47页

作者： Saskia van Ruth Elena Boscaini Dagmar Mayr Jonathan Pugh Maarten Posthumus 刘蓉刘志敏食品学院食品科学与营养专业科克大学 Institut für Ionenphysik利奥波德-费的南大学因思布鲁克市奥地利256020 应用研究实验室 MicromassUK.Ltd. 有机化学实验室食品学院Wageningen大学研究中心不详

用嗅觉测量法-气相色谱联用(GC-O),火焰离子检测器-气相色谱联用(GC-FID),质谱-气相色谱联用(GC-MS)三种气相色谱检测方法和常压化学离子化飞行时间质谱(APCI-TOFMS),质子传递反应质谱(PTR-MS)两种直接质谱检测方法来比较测定干辣椒中... 详细信息

用嗅觉测量法-气相色谱联用(GC-O),火焰离子检测器-气相色谱联用(GC-FID),质谱-气相色谱联用(GC-MS)三种气相色谱检测方法和常压化学离子化飞行时间质谱(APCI-TOFMS),质子传递反应质谱(PTR-MS)两种直接质谱检测方法来比较测定干辣椒中的挥发性香味成分。干辣椒的挥发性香味成分的大体描述最后由感官评定来确定。三种较显著的风味分别是:辣椒味、煮熟蔬菜味和青草味。用气质联用顶空分析法共有63种挥发性香味成分被分离出来。而嗅觉测量法-气相色谱联用(GC-O)认为其中的11种成分决定了辣椒的香味活跃程度。在所有的方法中普遍认为:3-甲基正丁醛是最活跃的香味成份,其次是2-甲基正丁醛。确定挥发性香味成分的多少主要是受测定方法的影响。色谱方法之间有很强的相关性(ρ=0.946)。直接质谱法相关性不显著(ρ=0.613)。经过不同方法的分析,我们发现,用GC-MS,GC-FID和PTR-MS三种方法检测出的挥发性香味成分并没有显著的不同,显著性的差异主要存在于PCI-TOFMS法和其工艺的不同(P<0.01).(Int J Mass Spectrom223-224(2003)55-65)

关键词： APCI-TOFMS GC-FID GC-MS GC-O PTR-MS

Climate Services for Water Resource Management in China: The Case Study of Danjiangkou Reservoir

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Journal of Meteorological Research 2021年第1期35卷 87-100页

作者： Yujie WANG Xiang LI Song LIU Zhenyu HAN Lianchun SONG Zongjian KE Keyao CHEN Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044 National Climate Center China Meteorological AdministrationBeijing 100081 Hanjiang Water Resources&Hydropower Group Co. Ltd.Wuhan 430000

The efficiencies and effectiveness of water resource management are inextricably linked to climate services. This study demonstrates a climate information service for Danjiangkou Reservoir, which is the largest artificial lake in Asia, facing mounting challenges for flood control, water storage, and water diversion. Unlike traditional water resource management on the basis of short-term weather forecast and runoff monitoring, subseasonal to seasonal(S2S)and annual climate predictions as well as long-term climate change projections were well used to support the decision makers in Danjiangkou Reservoir. The National Climate Center(NCC) has projected the changes of future climate and extreme events by dynamically downscaling the Coupled Model Intercomparison Project phase 5(CMIP5)projections to 25-km resolution for the long-term planning of water resource management in Danjiangkou ***-time climate predictions based on climate models and downscaling interpretation and application methods at different timescales were also provided to meet the specific needs of earlier predictions and spatial refinement for the short-term diversion of the reservoir. Our results show that such climate services facilitated the Diversion Center of Danjiangkou Reservoir(DCDR) to reasonably control the operational water level, increased the ecological water supply to the northern portion of China by 844 million m^(3), and reduced as much as 1.67 billion m^(3) of abandoned water in 2019. In the future, it is necessary to develop climate prediction methods to increase spatial and temporal resolutions and prediction skills, and enhance interactions between providers and users.

关键词： climate service water resource management climate prediction climate projection reservoir

雷击电弧气爆效应对风机的损伤机制与叶片优化设计

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中国电机工程学报 2020年第8期40卷 2705-2714页

作者：李宏博张敏昊李庆民于万水郭子炘 Siew Wah Hoon 新能源电力系统国家重点实验室(华北电力大学) 北京市昌平区102206 内蒙古电力(集团)有限责任公司内蒙古自治区呼和浩特市010020 思克莱德大学 Glasgow G11XQ UK

风机叶片雷击灾害事故频发,而雷击电弧对叶片气爆损伤机制尚不清晰,传统实验手段难以测量损伤过程中的细节参数。因此,以实际风机叶片为基础,搭建雷击电弧路径几何模型。基于磁流体动力学理论,利用有限元仿真软件COMSOL分别探究温度和... 详细信息

风机叶片雷击灾害事故频发,而雷击电弧对叶片气爆损伤机制尚不清晰,传统实验手段难以测量损伤过程中的细节参数。因此,以实际风机叶片为基础,搭建雷击电弧路径几何模型。基于磁流体动力学理论,利用有限元仿真软件COMSOL分别探究温度和压力在叶片内部的分布情况。进一步,对比不同引弧方式和雷击点位置对叶片材料碳化程度和后缘压力最大值的影响作用。发现叶片在遭受雷击后,雷击点的温度先迅速升高至最大值,然后缓慢降低,高温区域主要分布在雷击电弧周围。叶片后缘的压力先增加至峰值,然后呈现震荡衰减趋势。高压力区域先分布在右侧腹板与后缘之间,后逐渐向整个叶腔内扩散。叶片材料碳化程度和后缘压力最大值与已有文献的实验结果较为吻合,验证了仿真模型的正确性。当雷击点靠近叶尖时,叶片材料碳化程度和后缘压力最大值呈现上升趋势,当引下线布置于主梁时,上述两者均低于引下线布置于右侧腹板的情况。最后,从防雷角度出发,建议将引下线布置于主梁,同时使用环氧树脂将叶片后缘粘接处浇铸成半径为30mm的圆角。

关键词：风机叶片雷击防护损伤机制优化设计

Comparative and population genomics of buckwheat species reveal key determinants of flavor and fertility

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Molecular Plant 2023年第9期16卷 1427-1444页

作者： Kaixuan Zhang Yuqi He Xiang Lu Yaliang Shi Hui Zhao Xiaobo Li Jinlong Li Yang Liu Yinan Ouyang Yu Tang Xue Ren Xuemei Zhang Weifei Yang Zhaoxia Sun Chunhua Zhang Muriel Quinet Zlata Luthar Mateja Germ Ivan Kreft Dagmar Janovska Vladimir Meglic Barbara Pipan Milen I.Georgiev Bruno Studer Mark A.Chapman Meiliang Zhou Institute of Crop Sciences Chinese Academy of Agricultural SciencesNational Crop Genebank BuildingZhongguancun South Street No.12Haidian DistrictBeijing 100081China College of Agronomy Sichuan Agricultural UniversityChengdu 611130China Annoroad Gene Technology(Beijing)Co. LtdBeijing 100176China College of Agriculture Institute of Agricultural BioengineeringShanxi Agricultural UniversityTaigu 030801ShanxiChina Shanxi Key Laboratory of Minor Crops Germplasm Innovation and Molecular Breeding Shanxi Agricultural UniversityTaiyuan 030031ShanxiChina Tongliao Institute Agricultural and Animal Husbandry Sciences Tongliao 028015Inner MongoliaChina Groupe de Recherche en Physiologie Ve´ge´tale(GRPV) Earth and Life Institute-Agronomy(ELI-A)Universite´Catholique de LouvainCroix du Sud 4-5bo^ıte L7.07.13B-1348Louvain-la-NeuveBelgium Biotechnical Faculty University of Ljubljana1000 LjubljanaSlovenia Nutrition Institute Trzaska 401000 LjubljanaSlovenia Gene Bank Crop Research InstituteDrnovska´507Prague 6Czech Republic Agricultural Institute of Slovenia Hacquetova ulicaLjubljanaSlovenia Laboratory of Metabolomics Institute of MicrobiologyBulgarian Academy of SciencesPlovdivBulgaria Center of Plant Systems Biology and Biotechnology PlovdivBulgaria Molecular Plant Breeding Institute of Agricultural SciencesETH ZurichUniversitaetstrasse 28092 ZurichSwitzerland Biological Sciences University of SouthamptonLife Sciences Building 85Highfield CampusSouthampton SO171BJUK

Common buckwheat(Fagopyrum esculentum)is an ancient crop with a world-wide *** to its excellent nutritional quality and high economic and ecological value,common buckwheat is becoming increasingly important throughout the *** availability of a high-quality reference genome sequence and population genomic data will accelerate the breeding of common buckwheat,but the high heterozygosity due to the outcrossing nature has greatly hindered the genome *** we report the assembly of a chromosome-scale high-quality reference genome of *** ***,a homozygous self-pollinating variant of common *** genomics revealed that two cultivated buckwheat species,common buckwheat(***)and Tartary buckwheat(***),underwent metabolomic divergence and ecotype *** expansion of several gene families in common buckwheat,including FhFAR genes,is associated with its wider distribution than Tartary *** number variation of genes involved in the metabolism of flavonoids is associated with the difference of rutin content between common and Tartary ***,we present a comprehensive atlas of genomic variation based on whole-genome resequencing of 572 accessions of common *** and evolutionary genomics reveal genetic variation associated with environmental adaptability and floral development between Chinese and non-Chinese cultivated ***-wide association analyses of multi-year agronomic traits with the content of flavonoids revealed that Fh05G014970 is a potential major regulator of flowering period,a key agronomic trait controlling the yield of outcrossing crops,and that Fh06G015130 is a crucial gene underlying flavor-associated ***,we found that the gene translocation and sequence variation of FhS-ELF3 contribute to the homomorphic self-compatibility of common ***,our results elucidate the genetic basis of spe

关键词： buckwheat genomics natural variation adaptation flavonoids Fagopyrum

Effect of human umbilical cord-derived mesenchymal stem cells on lung damage in severe COVID-19 patients:a randomized,double-blind,placebo-controlled phase 2 trial

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Signal Transduction and Targeted Therapy 2021年第3期6卷 888-896页

作者： Lei Shi Hai Huang Xuechun Lu Xiaoyan Yan Xiaojing Jiang Ruonan Xu Siyu Wang Chao Zhang Xin Yuan Zhe Xu Lei Huang Jun-Liang Fu Yuanyuan Li Yu Zhang Wei-Qi Yao Tianyi Liu Jinwen Song Liangliang Sun Fan Yang Xin Zhang Bo Zhang Ming Shi Fanping Meng Yanning Song Yongpei Yu Jiqiu Wen Qi Li Qing Mao Markus Maeurer Alimuddin Zumla Chen Yao Wei-Fen Xie Fu-Sheng Wang Department of Infectious Diseases Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijingChina Wuhan Huoshenshan Hospital WuhanChina Department of Respiratory Changzheng HospitalSecond Military Medical UniversityShanghaiChina Optical Valley Branch of Maternal and Child Hospital of Hubei Province WuhanChina Department of Hematology Second Medical Center of Chinese PLA General HospitalBeijingChina Peking University Clinical Research Institute Peking University First HospitalBeijingChina Department of Infectious Disease General Hospital of Central Theater CommandWuhanChina VCANBIO Cell&Gene Engineering Corp. LtdTianjinChina National Industrial Base for Stem Cell Engineering Products TianjinChina Department of Hematology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Key Laboratory of Cancer Center Fifth Medical Center of Chinese PLA General HospitalBeijingChina Department of Endocrinology and Metabolism Changzheng HospitalSecond Military Medical UniversityShanghaiChina Department of Radiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Nursing Department Fifth Medical Center of Chinese PLA General HospitalBeijingChina immunotherapy Programme Champalimaud Centre for the UnknownLisbonPortugal Med Clinic University of MainzMainzGermany Center for Clinical Microbiology Division of Infection and ImmunityUniversity College Londonand UCL Hospitals NIHR Biomedical Research CentreLondonUK Department of Gastroenterology Changzheng HospitalSecond Military Medical UniversityShanghaiChina

Treatment of severe Coronavirus Disease 2019(COVID-19)is *** performed a phase 2 trial to assess the efficacy andsafety of human umbilical cord-mesenchymal stem cells(UC-MScs)to treat severe coViD-19 patients with lung damage,based onour phase 1 *** this randomized,double-blind,and placebo-controlled trial,we recruited 101 severe coVID-19 patients withlung *** were randomly assigned at a 2:1 ratio to receive either UC-MSCs(4×10^(7)cells per infusion)or placebo on day 0,3,and *** primary endpoint was an altered proportion of whole lung lesion volumes from baseline to day *** imagingoutcomes,6-minute walk test(6-MWT),maximum vital capacity,diffusing capacity,and adverse events were recorded and *** all,100 COVID-19 patients were finally received either UC-MSCs in=65)or placebo(n=35).UC-MSCs administrationexerted numerical improvement in whole lung lesion volume from baseline to day 28 compared with the placebo(the mediandifference was-13.31%,95%Cl-29.14%,2.13%,P=0.08).UC-MSCs significanty reduced the proportions of solid componentlesion volume compared with the placebo(median difference:-15.45%;95%CI-30.82%,-0.39%;P=0.043).The 6-MWT showedan increased distance in patients treated with UC-MSCs(difference:27.00 m;95%CI 0.00,57.00;P=0.057).The incidence of adverseevents was similar in the two *** results suggest that UC-MSCs treatment is a safe and potentially effective therapeuticapproach for COVID-19 patients with lung damage.A phase 3 trial is required to evaluate effects on reducing mortality andpreventing long-term pulmonary disability.

关键词： damage patients double