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Fluid Dynamics & Materials Processing 2024年第1期20卷 127-145页

作者： Shiyang Song tongxin han Postgraduate Department China Academy of Railway SciencesBeijing100081China Locomotive&Car Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China

Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips,which exacerbates wear and affects the current collection performance of the pantograph-catenary system,a study has been conducted to support the beam deflector optimization using a combination of experimental measurements and computational fluid dynamics(CFD)*** results demonstrate that the size,position,and installation orientation of the wind deflectors significantly influence the amount of force *** also indicate that the front strip deflectors should be installed downwards and the rear strip deflectors upwards,thereby forming a“π”***,the lift force compensation provided by the wind deflectors increases with the size of the *** wind compensation strategies,such as control circuits,are also discussed,putting emphasis on the pros and cons of various pantograph types and wind compensation approaches.

关键词： High-speed pantograph aerodynamic lift force supporting beam wind deflectors computational fluid dynamics(CFD)

Evaluation and projection of marine heatwaves in the South China Sea: insights from CMIP6 multi-model ensemble

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Acta Oceanologica Sinica 2024年第7期43卷 15-25页

作者： Kai Liu Kang Xu tongxin han Congwen Zhu Nina Li Anboyu Guo Xiaolu Huang National Marine Environmental Forecasting Center Beijing 100081China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China National Meteorological Center China Meteorological AdministrationBeijing 100081China Inner Mongolia Autonomous Region Meteorological Observatory Huhhot 010051China

This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2014),and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP)scenarios(SSP126,SSP245,and SSP585)using CMIP6 *** demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME)results showing the best *** reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature *** various SSP scenarios,the year 2040 emerges as pivotal juncture for future shifts in SCS MHWs,marked by distinct variations in changing rate and *** is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity,duration,and total days after ***,the projection results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future ***,the intensity shows higher consistency only during the near-term period(2021−2050),while notable inconsistencies are observed during the medium-term(2041−2070)and long-term(2071−2100)periods under the three SSP *** the nearterm period,the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter *** contrast,during the medium-term period,MHWs are also characterized by moderate and strong events,but with longer-lasting and more intense events under the SSP245 and SSP585 ***,in the long-term period,extreme MHWs become the dominant feature under the SSP585 scenario,indicating a substantial intensification of SCS MHWs,effectively establishing a near-permanent state.

关键词： marine heatwaves South China Sea global warming future projections CMIP6

针对高速列车受电弓气动特性仿真的不同湍流模型适用性研究

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中国铁道科学 2024年第2期45卷 164-174页

作者：宋诗扬韩通新中国铁道科学研究院研究生部北京100081 中国铁道科学研究院集团有限公司机车车辆研究所北京100081

为探究高速受电弓气动特性仿真时不同湍流模型在不同运行环境中的适用性,基于k-ε,SST k-ω和Spalart-Allmaras 3个湍流模型的理论基础和计算流体力学仿真方法,通过线路试验对仿真结果进行验证后,对比不同模型在开阔环境和隧道环境中的... 详细信息

为探究高速受电弓气动特性仿真时不同湍流模型在不同运行环境中的适用性,基于k-ε,SST k-ω和Spalart-Allmaras 3个湍流模型的理论基础和计算流体力学仿真方法,通过线路试验对仿真结果进行验证后,对比不同模型在开阔环境和隧道环境中的精确度和计算效率。结果表明:在300 km·h^(-1)速度下,SST k-ω与k-ε模型在开阔环境中的闭口和开口方向气动抬升力计算结果差异分别为0.7%和1.5%,与Spalart-Allmaras模型计算结果差异分别为7.1%和5.5%;SST k-ω和k-ε模型在边界层预测均匀,Spalart-Allmaras模型在边界层分离区的预测准确性较低,但在隧道环境中它的精确度高于k-ε模型;在计算效率方面,Spalart-Allmaras模型的迭代次数和收敛速度优于SST k-ω模型;在适用性方面,开阔环境中k-ε模型的精确度和计算效率表现优异,更为适用,而在隧道环境中Spalart-Allmaras模型具有较高的精确度和计算效率,更为适用,但在对精确度要求高且可忽略计算效率因素的情况下SST k-ω模型具有较好适用性和高精确度,更为适用。

关键词：高速列车受电弓气动特性湍流模型适用性气动抬升力计算流体力学仿真

Gene mutations and clinical phenotypes in Chinese children with Blau syndrome

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Science China(Life Sciences) 2017年第7期60卷 758-762页

作者： Caifeng Li Junmei Zhang Shipeng Li tongxin han Weiying Kuang Yifang Zhou Jianghong Deng Xiaohua Tan Department of Rheumatology and Immunology Beijing Children's Hospital Capital Medical University National Center for Children's Health Beijing 100045 China

The mutations of CARD15 gene and clinical features of Chinese patients with Blau syndrome were analyzed. We identified10 missense mutations, out of which five were new: R334 L, E383 D, R471 C, C495 R and D512 F. The rest of them, R334 W,R334Q, G481 D, M513 T and R587 C, have been reported previously. Among all the mutations, R334 W, R334 Q and C495 R had the highest frequency. Blau syndrome was found at early age after birth. It began with lepidic rash and symmetric polyarthritis and was phenotypically characterized by typical rash, arthritis, iridocyclitis and arteritis. Cardiac involvement was also found in Blau syndrome. In addition to nerve deafness, renal involvement, osteochondroma and central nervous system involvement were also found in our patients. Therefore, Chinese children with Blau syndrome have unique gene mutations and complicated clinical phenotypes. Pathologic examination and CARD15 mutation testing should be considered for diagnosis as early as possible for suspected patients.

关键词： Blau syndrome genetic mutation clinical phenotype

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重载铁路弓网状态一体化监测架构及装置研究

电气化铁道 2024年第4期35卷 37-40,49页

作者：秦传鑫王志良韩通新尹彦宏中国国家铁路集团有限公司中国铁道科学研究院集团有限公司机车车辆研究所

通过分析高速铁路弓网状态监测系统架构,研究适用于重载铁路的弓网状态一体化监测系统架构及装置。根据功能要求研究线结构光3D相机接触网几何参数和磨耗检测技术,实现接触网几何参数和磨耗的高精度测量;研究基于光电倍增管的燃弧检测技... 详细信息

通过分析高速铁路弓网状态监测系统架构,研究适用于重载铁路的弓网状态一体化监测系统架构及装置。根据功能要求研究线结构光3D相机接触网几何参数和磨耗检测技术,实现接触网几何参数和磨耗的高精度测量;研究基于光电倍增管的燃弧检测技术,实现了弓网燃弧高精度测量,具备燃弧功率密度和燃弧时间同时连续测量的功能;研究受电弓红外测温技术、受电弓视频监控技术、接触网零部件高清拍照技术,实现明显故障缺陷自动识别功能。根据技术研究成果研发了试验样机,经在重载机车上运行测试,运行效果良好,测试数据满足要求,实现预期目标。

关键词：重载铁路弓网状态监测架构结构光光电倍增管

Gene mutations and clinical phenotypes in 15 Chinese children with cryopyrin-associated periodic syndrome(CAPS)

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Science China(Life Sciences) 2017年第12期60卷 1436-1444页

作者： Caifeng Li Xiaohua Tan Junmei Zhang Shipeng Li Wenxiu Mo tongxin han Weiying Kuang Yifang Zhou Jianghong Deng Department of Rheumatology and Immunology Beijing Children's HospitalCapital Medical UniversityNational Center for Children"s HealthBeijing 100045China

The aim of our study is to explore the features of clinical manifestations and genetic mutations in Chinese CAPS patients. Fifteen confirmed patients with CAPS were enrolled. The onset time ranges from 2 days after birth to 6 years and 1 month. Recurrent urticaria rash(93.3%) with fever(100%) were two dominant characteristics of these patients that were presented as either acute or chronic process. Systemic involvements were found in all patients except for one with only rash and fever. The top three symptoms were fever(100%), rash(93.3%) and myalgia(76%). Other clinical manifestations include arthritis(11 cases), lung involvement(seven cases), optical dysfunction(seven cases), nerve deafness(six cases), nervous system involvement(five cases), hepatomegaly, splenomegaly and lymphadenectasis(five cases). Also, four patients had heart involvement and one patient suffered kidney involvement. The laboratory inflammation index such as leukocyte counts, platelet counts, erythrocyte sedimentation rate(ESR), C-reactive protein(CRP), serum amyloid A(SAA) and fibrinogen(FIB) increased significantly at initial stage, but decreased after therapy. As for gene mutation detection, Twelve out of 15 patients were confirmed with mutation in NLRP3, including 11 mutant site: c1789 A>G, c.1703 T>A, c.913 G>A, c.1710 G>C, c.1057 G >T, c.2335 C>T, c.932 T>C,c.296 G>C, c.663 C>T, t.1702 T>A, 299 G>A. Mutation sites c.1703 T>A, c.2335 C>T, c.296 G>C, c.663 C>T, and 299 G>A were newly identified. The association between gene mutation and clinical manifestation shows that D305 N was highly associated with severe organs involvements, and therefore, the time of therapy and regimen were critical for the prognosis of disease. As the largest cohort study of Chinese CAPS patients, we confirmed that all patients presented typical clinical manifestations, identified five new mutation sites on NLRP3 and analyzed the correlation between the genotypes and phenotypes. We also raise concerns for one case

关键词： CAPS genetic mutation clinical phenotTpe NLRP3

气象大数据云平台仿真环境容器调度性能优化研究

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气象科技 2024年第3期52卷 340-346页

作者：吴鹏韩同欣陈士旺聂元丁郑晓志国家气象信息中心北京100081 广州市海珠区气象局广州510240

为实现2025年气象关键核心技术自主可控的目标,气象大数据云平台(简称天擎)建立了基于海光X86服务器和麒麟操作系统的仿真环境。在仿真平台运行中发现,基于容器技术的产品加工与流水线子系统容器调度性能较差,不能满足用户融入算法的时... 详细信息

为实现2025年气象关键核心技术自主可控的目标,气象大数据云平台(简称天擎)建立了基于海光X86服务器和麒麟操作系统的仿真环境。在仿真平台运行中发现,基于容器技术的产品加工与流水线子系统容器调度性能较差,不能满足用户融入算法的时效要求。针对此问题,本文采用对比分析法,选取天擎仿真环境和业务环境的3种CPU芯片服务器和3种操作系统为研究对象,设计了一系列组合对比测试用例,找到了影响容器调度性能的关键因素—操作系统内核,并进一步分析了操作系统内核设置对系统实时性和吞吐量的影响以及适用的业务场景。最后给出了麒麟操作系统内核调整方法,通过调整内核设置,容器调度性能大幅提高,满足了产品加工系统的时效要求,为实现天擎的关键核心技术自主可控奠定基础。

关键词：气象大数据云平台自主可控麒麟操作系统容器调度

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弓网接触状态光纤传感监测技术研究

现代城市轨道交通 2024年第3期 39-43页

作者：秦传鑫王志良韩通新尹彦宏白龙中国国家铁路集团有限公司北京100844 中国铁道科学研究院集团有限公司机车车辆研究所北京100081

在弓网检测的应用场景中,传统的测力传感器和加速度传感器依赖电源供电,且必须安装在高电压的受电弓上,从而增加额外的设备和复杂性。文章研究采用无源光纤布拉格光栅(FBG)光传感器,这种传感器无需额外安装供电电源和充电控制系统等设... 详细信息

在弓网检测的应用场景中,传统的测力传感器和加速度传感器依赖电源供电,且必须安装在高电压的受电弓上,从而增加额外的设备和复杂性。文章研究采用无源光纤布拉格光栅(FBG)光传感器,这种传感器无需额外安装供电电源和充电控制系统等设备。通过介绍光纤传感器的基本原理,并分析其应用场景,提出在弓网状态监测的高电压环境中,光纤传感器具有独特优势:不仅无需供电,减少额外设备,还能实现信号传输的高低压隔离,有效抵抗电磁干扰。针对受电弓检测的特殊需求,开发基于光纤传感技术的接触力和加速度传感器,其便于在受电弓上安装且对受电弓结构无影响。在列车受电弓上的实际安装测试中,成功实现对弓网接触力、硬点等参数的高精度检测。该弓网状态监测系统能够适用于专用检测车和运营动车组,大幅扩展弓网监测的应用范围。

关键词：高速铁路光纤传感器弓网接触力硬点状态监测

基于升弓高度的受电弓气动抬升系数计算方法与分析

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铁道学报 2023年第11期45卷 46-52页

作者：宋诗扬韩通新中国铁道科学研究院研究生部北京100081 中国铁道科学研究院集团有限公司机车车辆研究所北京100081

为研究不同运行方向、工作高度下高速受电弓的空气动能性能,推导受电弓各臂杆间夹角相对升弓高度的数学计算模型,计算不同升弓高度下高速受电弓气动抬升力和气动抬升系数;采用Fluent计算流体力学软件对高速受电弓不同运行速度、开/闭口... 详细信息

为研究不同运行方向、工作高度下高速受电弓的空气动能性能,推导受电弓各臂杆间夹角相对升弓高度的数学计算模型,计算不同升弓高度下高速受电弓气动抬升力和气动抬升系数;采用Fluent计算流体力学软件对高速受电弓不同运行速度、开/闭口运行方向和工作高度下气动抬升力、气动抬升系数进行仿真建模与数值求解;利用现场线路试验数据验证仿真结果和理论分析结论。结果表明:受电弓开口方向运行时,其工作高度与气动抬升系数、气动抬升力呈正相关,闭口方向运行时成负相关关系。一般情况下,开口方向运行的高速受电弓空气动力性能优于闭口方向。

关键词：受电弓气动抬升系数气动抬升力升弓高度

350 km/h及以上高速受电弓气动抬升力研究

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铁道科学与工程学报 2023年第10期20卷 3673-3684页

作者：宋诗扬孔龙飞韩通新中国铁道科学研究院研究生部北京100081 中国铁道科学研究院集团有限公司机车车辆研究所北京100081

以350 km/h及以上速度级的高速受电弓为研究目标,为400 km/h高速动车组受电弓气动抬升力仿真提供精准计算方法。通过计算流体力学软件ANSYS FLUENT对高速受电弓进行仿真建模,分别基于可压缩和不可压缩Navier-Stokes方程和SST k-ω湍流模... 详细信息

以350 km/h及以上速度级的高速受电弓为研究目标,为400 km/h高速动车组受电弓气动抬升力仿真提供精准计算方法。通过计算流体力学软件ANSYS FLUENT对高速受电弓进行仿真建模,分别基于可压缩和不可压缩Navier-Stokes方程和SST k-ω湍流模型,对350,380和420 km/h 3个速度级的高速受电弓气动抬升力进行仿真计算,发现相比使用可压缩流方法,3个速度级下使用不可压缩流计算得到的气动抬升力在开口方向和闭口方向运行时分别提升了8.2%,9.6%,11.8%和8.9%,10.6%,13.0%。为验证仿真结果,对京沪先导段线路进行高速弓网受流性能综合测试。研究结果表明:使用可压缩流进行仿真的准确性更高,3个速度级下的偏差在开口方向和闭口方向上分别为3.3%,3.1%,2.7%和3.1%,2.5%,1.7%。相较之下,使用不可压缩流的偏差在开口方向和闭口方向运行时分别为5.3%,7.3%,10.2%和6.5%,9.0%,13.0%。在特殊工况和狭窄环境中,采用可压缩流方法,420 km/h开口方向运行时,气动抬升力基于温度的提升为7.7%(0℃)和18.2%(−25℃),基于壁面横截面积的提升分别为19.0%(60 m^(2)),16.7%(70 m^(2)),14.5%(80 m^(2))和13.3%(90 m^(2))。因此,对400 km/h速度级及以上的高速动车组,建议采用可压缩流进行仿真以获得更精确的预测结果。对于现有350 km/h速度级的高速动车组,需考虑特殊工况和狭窄环境下气动抬升力的升高,通过合理优化措施提高列车运行的安全性和稳定性。

关键词：弓网空气动力学气动抬升力流体可压缩性仿真计算高速受电弓